Title:
Glass fiber forming compositions
Kind Code:
A1


Abstract:
Mathematical relationship for ingredients for fiber glass compositions are used to identify properties of the glass. In particular the forming temperature and delta T. In one embodiment, the mathematical relationship of the ingredients is of a generic quaternary SiO2, CaO, AI2O3 and MgO glass system. The relationship of SiO2, CaO, AI2O3 and MgO of interest include RO=CaO+MgO, SiO2/CaO, SiO2/RO, SiO2/AI2O3; AI2O3/CaO; SiO2+AI2O3; SiO2-RO and AI2O3/RO or RO/AI2O3 when other ingredients or components are added to the glass batch materials to alter the forming and/or liquidus temperatures of the glass, for example Na2O, Li2O, K2O and B2O3 the following mathematical relationships are of interest, (SiO2+AI2O3)/(R20+RO+B2O3) where RO is as previously defined and R2O=Na2O+Li2O+K2O. Each of the compositional features of the glass identified above reflects the relative balance between the fluidity (i.e. viscosity) of the glass melt and its crystallization potential. Low boron or boron free fiber glass compositions having a low forming temperature ,e.g. 1178 to 1240° C. and a delta T greater than 50° C. in order that the composition can be processed at a low temperature while reducing the possibility of devitrification of the molten glass in the bushing area during a glass fiber forming operation. Fiber glass compositions having low. boron, e.g. less than 5.10 percent by weight has a low forming temperature, e.g. 1193 to 1240° C. and a delta T greater than 50° C.



Inventors:
Wallenberger, Frederick T. (Allegheny, PA, US)
Application Number:
11/017331
Publication Date:
05/26/2005
Filing Date:
12/20/2004
Assignee:
WALLENBERGER FREDERICK T.
Primary Class:
Other Classes:
501/70
International Classes:
C03C3/087; C03C3/091; C03C3/093; C03C3/118; C03C13/00; C03C13/02; C03C13/06; (IPC1-7): C03C3/087; C03C13/00
View Patent Images:



Primary Examiner:
BOLDEN, ELIZABETH A
Attorney, Agent or Firm:
PPG Industries, Inc. (Pittsburgh, PA, US)
Claims:
1. A glass composition comprising:
SiO256 to 59percent by weight;
Al2O310 to 14percent by weight;
CaO21 to 25percent by weight;
MgO2 to 4percent by weight;
TiO20 to 1.5percent by weight;
Na2O0 to 1.25percent by weight;
Na2O + K2O0 to 2percent by weight;
Fe2O30 to 0.5percent by weight;
B2O3less than 1.10percent by weight;
Li2Oessentially none;
MnO or MnO2 2 to 4 percent by weight; wherein the glass composition has a log 3 forming temperature no greater than 1230° C., and the difference between the log3 forming temperature and the liquidus temperature is at least 50° C.

2. The glass composition according to claim 1, wherein the glass composition is essentially free of B2O3.

3. The glass composition according to claim 1, wherein the glass includes no deliberate addition of fluorine-containing constituents.

4. The glass composition according to claim 1, wherein the ratio of SiO2 to (CaO+MgO) is no greater than 2.30.

5. The glass composition according to claim 1, wherein the ratio of SiO2 to (CaO+MgO) is from 2.00 to 2.30.

6. The glass composition according to claim 1, wherein (Na2O+K2O) is no greater than about 1.03 percent by weight.

7. The glass composition according to claim 1, wherein (Na2O+K2O) is no greater than 1 percent by weight.

8. The glass composition according to claim 1, wherein the composition includes MnO in an amount no greater than 4 percent by weight.

9. The glass composition according to claim 1, wherein the composition includes MnO2 in an amount no greater than 4 percent by weight.

10. A glass composition comprising:
SiO257 to 59percent by weight;
Al2O311 to 14percent by weight;
CaO22 to 24percent by weight;
MgO2 to 3percent by weight;
TiO20 to 2percent by weight;
Na2O0 to 1percent by weight;
Na2O + K2O0 to 2percent by weight;
Fe2O30.1 to 0.5percent by weight;
B2O3less than 1.0percent by weight;
Li2Oessentially none;
MnO or MnO2 2 to 4 percent by weight; wherein the glass composition has a log 3 forming temperature no greater than 1230° C., and the difference between the log3 forming temperature and the liquidus temperature is at least 50° C.

11. The glass composition according to claim 10, wherein the SiO2 is less than 58 percent by weight.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No. 10/164,468, filed Jun. 6, 2002, which claims benefit of U.S. Provisional Application Nos. 60/330,178, filed Oct. 18, 2001; 60/230,474, filed Sep. 6, 2000 and 60/136,538, filed May 28, 1999. U.S. patent application Ser. No. 10/164,468 is a 35 USC 371 of PCT application Ser. No. PCT/US01/27451, filed Sep. 5, 2001 (now U.S. Pat. No. 6,818,575), which claims benefit of U.S. Provisional Application No. 60/230,474, filed Sep. 6, 2000, and which is a continuation in part of U.S. patent application Ser. No. 09/980,248, filed Nov. 28, 2001 (now U.S. Pat. No. 6,686,304 B1), which is a 35 USC 371 of PCT application Ser. No. PCT/US00/14155 and claims benefit of U.S. Provisional Application 60/136,538, filed May 28, 1999.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to glass compositions, and more particularly to (1) fiber glass compositions, and (2) mathematical relationships of the ingredients of the glass compositions to identify thermal properties of the glass compositions e.g., forming and liquidus temperatures with an acceptable temperature difference to prevent devitrification of the molten glass during forming of glass fibers.

2. Discussion of the Technology

In the art of forming glass fibers it is recognized that the difference between the forming temperature and liquidus temperature is maintained at a value to prevent devitrification of the molten glass during fiber forming. For example, the most common glass composition for making continuous glass fiber strands for textiles and glass fiber reinforcements is known in the trade as “E glass”. The requirements as to what type of composition constitutes an E-glass composition are included in ASTM D578-00. An advantage of using E-glass having 6-10 percent by weight B203 is that its liquidus temperature is well below its forming temperature, i.e. typically greater than 56° C. (100° F.) and usually in the range of 83 to 111° C. (150 to 200° F.). As used herein, the terms “forming temperature”, “TFORM”, “log 3 forming temperature” and “log3 FT” mean the temperature of the glass at which the viscosity of the glass is log 3, or 1000 poise, and the terms “liquidus temperature”, “liquidus T” and “TLIQ” mean the temperature at which the solid phase (crystals) and liquid phase (melt) of the glass are in equilibrium. The difference between TFORM and TLIQ, referred to herein as “delta T” or “ΔT”, is a common measure of the crystallization potential of a given melt composition. The lower the ΔT, in other words the smaller the difference between the forming temperature and the liquidus temperature, the greater the crystallization potential. In the glass fiber forming industry, ΔT is typically maintained at a temperature of at least 50° C. (90° F.) in order to prevent devitrification of the molten glass during a glass fiber forming operation, in particular, in the bushing area.

It is appreciated by those skilled in the art of forming glass fibers, that it is desirable to operate the glass fiber forming operation at low temperatures because operating the glass fiber forming operation at high temperatures results in high-energy usage, along with associated high-energy costs. In addition, the high temperatures accelerate degradation of the refractories used in the glass melting furnace, as well as the bushings used to form the fibers. The bushings include precious metals that cannot be recovered from the glass as the bushings wear.

It is recognized that boron and fluorine in addition to contributing to the electrical properties of the E-glass, e.g. dissipation factor and dielectric constant, also lower the forming and liquidus temperatures of the glass while providing a ΔT of at least 50° C. (90° F.). The boron in the form of an oxide and fluorine in the form of a fluoride are included in the glass batch materials and act as fluxes during the glass melting operation. E-glass can include up to 10 wt % B2O3 and up to 1.0 wt % fluoride (see ASTM D 578-00 §4.2). Although the boron effectively lowers the forming and liquidus temperatures while providing an acceptable ΔT value and the fluoride or fluorine acts as a flux, there are drawbacks. More particularly, these materials volatilize during melting and move with the exhaust gases into the exhaust system. If the boron and fluorine in the exhaust gases are not removed they are released to the atmosphere. Since boron and fluorine are considered pollutants, these emissions are closely controlled by environmental regulations, which in turn require careful control of the furnace operations and/or the use of costly additional pollution control equipment. In response to these concerns, the boron and/or fluorine content in E-glasses were reduced. For example, U.S. Pat. Nos. 4,542,106 and 5,789,329 and WO 99/12858 disclose boron free or low boron e.g. 1.8 wt % glasses having a forming temperature in the range of about 1258 to 1263° C. As can be appreciated by those skilled in the art of glass making, reducing or removing the boron and/or fluorine content in the batch materials raises the forming temperature. More particularly, the silica content increases as the boron content decreases, resulting in an increase in the forming temperature. As mentioned above, increasing the forming temperature results in high-energy usage, high-energy costs, and acceleration of the degradation of furnace refractories and bushings used to form the fibers.

For additional information concerning glass compositions and methods for fiberizing the glass composition, see K. Loewenstein, The Manufacturing Technology of Continuous Glass Fibres, (3d Ed. 1993) at pages 30-44, 47-60, 115-122 and 126-135, and F. T. Wallenberger (editor), Advanced Inorganic Fibers: Processes, Structures, Properties, Applications, (1999) at pages 81-102 and 129-168, which documents are hereby incorporated by reference.

In general, glass compositions having particular properties, e.g. forming temperature and delta T are identified by weight percent and/or molar percent of the components or ingredients in the glass. As can be appreciated by those skilled in the art of glass making and/or glass fiber forming, it would be advantageous to identify the performance of the glass compositions not only by the amount of a particular ingredient in the glass but also by a relationship, e.g. a mathematical relationship of the ingredients in the glass. WO 01/32576A1 discloses fiber glass compositions and the mathematical relationship of several of the ingredients, e.g. the combined Wt % of CaO and MgO, and the ratio of AI2O3/CaO, in the glass. Using the combination of glass ingredients, e.g. the absolute weight percent of silica with the relationship of other ingredients in the glass, e.g. the ratio of silica to RO (combined Wt % of CaO and MgO) would provide information regarding the melt properties of the glass.

SUMMARY OF THE INVENTION

The present invention provides a low boron containing or a boron free glass fiber forming composition that has a forming temperature of no greater than 1240° C. (2262° F.), a ΔT of at least 50° C. (90° F.), and one or more or all of the following compositional features:

a ratio of SiO2 to RO (i.e. CaO+MgO) in the range of 1.9 to 2.55;

a ratio of SiO2 to CaO in the range of 2.1 to 2.8;

a ratio of SiO2 to AI2O3 in the range of 3.7 to 5.0;

a ratio of AI2O3 to CaO in the range of 0.5 to 0.6;

a sum of SiO2 and AI2O3 in the range of 66.0 to 73.7 wt %;

a ratio of (SiO2+AI2O3) to (R2O+RO+B2O3) in the range of 2.0 to 3.0;

a ratio of AI2O3 to RO in the range of 0.4 to 0.6; and

a difference between SiO2 and RO; in the range of 26.5 to 36.6 wt %.

In one nonlimiting embodiment of the present invention, the glass composition further has a SiO2 content of greater than 57 weight percent and B2O3 of no greater than 2 weight percent. In another nonlimiting embodiment of the invention, the SiO2+AI2O3 content of the glass composition is less than 70 weight percent. In still another nonlimiting embodiment of the invention, the glass composition contains at least 1 weight percent TiO2.

In the discussion under Description of the Preferred Embodiments are glass compositions and mathematical relationship of different types of glasses. One such glass composition has the following ingredients:

SiO255.70 to 59percent by weight;
Al2O312.35 to 13.94percent by weight;
CaO24.40 to 24.80percent by weight;
MgO2.55 to 2.80percent by weight;
TiO20.05 to 0.55percent by weight;
Na2O0.40 to 0.50percent by weight;
K2O0.40 to 0.60percent by weight;
Na2O + K2O0.85 to 1.50percent by weight;
Fe2O30.20 to 0.40percent by weight, and
B2O31.25 to 1.55percent by weight, and

the following relationship of ingredients

RO26.25 to 27.60 wt %
SiO2/CaO 2.20 to 2.40
SiO2/RO 2.00 to 2.20
SiO2/Al2O3 3.95 to 4.70
Al2O3/CaO 0.50 to 0.60
SiO2 + Al2O369.00 to 70.50 wt %
SiO2 − RO28.00 to 31.00 wt %
Al2O3/RO 0.45 to 0.55
R2O + RO + B2O328.90 to 30.00 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.25 to 2.45 and

a log3 forming temperature in the range of 1210 to 1225° C. and ΔT is in the range of 52 to 65° C. R2O is equal to the wt % of k2O and Na2O.

Reference should be made to the Description of the Preferred Embodiments thereto for a more detailed summary of the glass compositions of the invention and the relationship of the ingredients of the glass compositions.

The glass compositions meeting the mathematical relationships of the instant invention provide a glass having a forming temperature of less than 1240° C., preferably 1205 to 1220° C., and more preferably between 1211 to 1218° C. for boron free glass and more preferably between 1187 to 1205° C. for boron containing glasses.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following discussion, all numbers expressing dimensions, physical characteristics, and so forth, used in the specification and claims are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical values set forth in the following specification and claims can vary depending upon the desired properties obtained by the practice of the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Moreover, all ranges disclosed herein are to be understood to encompass any and all subranges subsumed therein. For example, a stated range of 1 wt % to 10 wt % should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more and ending with a maximum value of 10 or less, e.g., 5.5 to 10.

It should be appreciated that, unless otherwise indicated, all numerical values discussed herein, such as but not limited to weight percent of materials or temperatures, are approximate and are subject to variations due to various factors well known to those skilled in the art such as, but not limited to, measurement standards, equipment and techniques. As a result, such values are to be understood as being modified in all instances by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any recognized deviations and/or errors are discussed. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

In the following discussion and in the claims the limits of defining the range are included in the range. For example and not limiting to the discussion, “in the range of 1230 to 1240° C.” and “in the range of equal to and greater than 1230° C. and equal to and less than 1240° C.” define the same range. Further in the preceding discussion, in the following discussion and in the claims, the terms “weight percent”, “wt %” and “percent by weight” are used herein interchangeably.

In one embodiment of the present invention, the mathematical relationships of the ingredients of a generic quaternary glass system are disclosed. The quaternary system includes SiO2, CaO, AI2O3 and MgO. As can be appreciated by those skilled in the art of making glass, in particular making glass fibers, MgO if not added to the batch materials is found in the batch materials as a tramp material, e.g. MgO is found in clay at 0.3 to 0.5 percent by weight. In the practice of the invention, MgO is added to the batch material to attain a level in the glass greater than the tramp level. The relationship of SiO2, CaO, AI2O3 and MgO of interest include RO=CaO+MgO, SiO2/CaO, SiO2/RO, SiO2/AI2O3; AI2O3/CaO; SiO2+AI2O3; SiO2-RO and AI2O3/RO or RO/AI2O3. In the present invention when other ingredients or components are added to the glass batch materials to alter the forming and/or liquidus temperatures of the glass and/or are present in the glass, for example but not limiting to the invention Na2O, Li2O, K2O and B2O3 the following mathematical relationships are of interest, (SiO2+AI2O3)/(R2O+RO+B2O3) where RO is as previously defined and R2O=Na2O +Li2O +K2O. In Tables 1 through 22, the relationship (SiO2 +AI2O3)/(R2O+RO+B2O3) is shown as (Si+AI)/(R2O+RO+B) to fit the formula into a reasonable column width. Each of the compositional features of the glass identified above reflects the relative balance between the fluidity (i.e. viscosity) of the glass melt and its crystallization potential, as will be discussed below in more detail. The physical melt properties of interest in the present discussion are the forming temperature and the liquidus temperature because embodiments of the present invention are to provide low boron or boron free glass compositions having a low forming temperature and a desired ΔT. In this manner, the glass can be processed, e.g. to form glass fibers at a low temperature while reducing the possibility of devitrification of the molten glass, e.g. in the bushing area. Without limiting the present invention, one embodiment of the invention includes a glass composition having a forming temperature of no greater than 1240° C. (2264° F.) and a ΔT of at least 50° C. (90° F.).

In the following discussion, the mathematical relationship is to the ingredients in the glass; however, the invention is not limited thereto and contemplates identifying and using the relationship of the ingredients to be added to the batch, e.g. mixing the batch prior to melting the batch to form the glass. Further, in the following discussion the mathematical relationship of the ingredients will be in wt % of the ingredients in the glass composition; however, the invention is not limited thereto and maybe the mole% or any measurement that identifies the amount of the ingredient in the batch materials and/or the glass composition.

In regards to the ingredients or constituents of the quaternary system presented above, it is known that pure silica is the highest melting glass former. A pure silica melt does not have a well defined melting point. At 2500° C. (4532° F.), it has a viscosity of greater than about log 4 (10,000) poise, and as it cools to room temperature, it gradually solidifies and forms a glass. Pure calcia, magnesia and alumina melts are known to have very low viscosities, e.g. in the range of 0.5-2.0 poise at their respective melting points. These materials do not solidify into a glass as the melt cools but rather crystallize instantly at their sharply defined melting point. In a typical quaternary SiO2-AI2O3-CaO-MgO glass composition with 55-60% SiO2 and 21-26% CaO, each oxide of the quaternary system contributes its unique characteristics toward its balance of melt properties.

Based on the material properties of the constituents of the quaternary system for a glass composition having these components, it can be inferred that as SiO2, which is the largest oxide component of the glass composition in terms of weight percent, is reduced in a given composition of this type, the melt viscosity and the resulting log 3 forming temperature drops. If CaO, which is the second largest component of the glass composition in terms of weight percent, or MgO is increased in such a composition, the effect of RO (CaO+MgO) on the glass properties will be twofold. More specifically, it will not only increase the fluidity of the resulting melt (i.e. decrease its viscosity and the forming temperature) but it will also increase the crystallizability of the resulting melt (i.e. increase its liquidus temperature), and therefore reduce the ΔT.

As a result, although not required, in one nonlimiting embodiment of the present invention, the glass compositions have (1) the lowest SiO2 content that will yield the lowest log 3 forming temperature, which in the present invention is below 1240° C., preferably below 1220° C. in combination with (2) the ratio of SiO2 to RO that yields the process-required ΔT, which in the present invention is at least 50° C. Based on the forgoing and although not required in the practice of the invention, in one nonlimiting embodiment of the present invention, the silica level is preferably no greater than 62 wt % SiO2, in order to promote a lower log 3 forming temperature. In other nonlimiting embodiments of the present invention, the glass compositions have no greater than 60 wt % SiO2 and no greater than 58 wt % SiO2.

In general, MgO is included in a glass fiber forming composition because it has been found that the heating and melting profile of a glass fiber composition, and in particular the liquidus temperature, can be controlled and in particular optimized by controlling the amount of MgO. More particularly, by regulating the amount of MgO, the liquidus temperature can be selected to provide a delta T of at least 50° C. In addition, it has been determined that a eutectic exists in a generic quaternary SiO2-AI2O3-CaO-MgO system at around 2.5-2.8 wt % MgO. For a discussion of the eutectic reference may be had to WO 00/73231 which document is hereby incorporated by reference.

The value of the SiO2/RO ratio can be manipulated by changing the amount of SiO2 and/or RO to produce a glass composition having a ΔT as close as possible to the minimum desire ΔT. A decrease in the value of SiO2/RO, which is indicative of a reduction in the wt % of SiO2 and/or an increase in the wt % of CaO and/or MgO, or any change or combination of changes in the wt % of the SiO2, CaO and/or MgO, will effect the melt viscosity and ΔT, and will increase the crystallization potential. Conversely, an increase in the value of SiO2/RO will effect the melt viscosity and ΔT, and will decrease the crystallization potential. It should be appreciated that if the value of SiO2/RO ratio drops too low, ΔT can drop to an unacceptable level. Although not required, in one nonlimiting embodiment of the present invention, SiO2/RO is no greater than 2.40. In other nonlimiting embodiments, SiO2/RO is no greater than 2.35, or no greater than 2.30, or no greater than 2.25, or no greater than 2.20. In still another nonlimiting embodiment of the invention, the value of SiO2/RO ranges from 1.9 to 2.55, e.g. from 2.1 to 2.55 for boron-free glasses and from 1.9 to 2.4 for boron containing glasses.

In addition to the SiO2 level and the SiO2/RO ratio, the following parameters also describe the compositional envelope level of a quaternary glass composition: the SiO2/CaO ratio, the SiO2/AI2O3 ratio, the AI2O3/CaO ratio, the sum of SiO2+AI2O3, the difference between SiO2-RO, and the AI2O3/RO ratio. The following parameters describe the compositional envelope level of a glass composition containing additional temperature modifying ingredients: the sum of R2O+RO+B2O3, where R2O=Na2O+K2O+Li2O and the (SiO2+AI2O3)/(R2O+RO+B2O3) ratio.

While the SiO2/RO ratio at a given silica level describes the compositional effect of RO on the crystallization potential and melt fluidity, the SiO2/CaO ratio shows only the effect of CaO on the crystallization potential. If the MgO and the SiO2 levels are kept constant in a comparison of various melts, a decrease in the value of SiO2/CaO will show an increase in crystallization potential due to the contribution of CaO and visa versa. The SiO2-RO difference serves as a similar indicator, i.e. a decrease in the difference or a smaller difference is typically indicative of a greater relative amount of RO and thus an increase in the crystallization potential. And conversely, an increase in the difference or a larger difference in SiO2-RO is indicative of a reduction in the crystallization potential. In one nonlimiting embodiment of the present invention, the SiO2/CaO ratio of the glass composition ranges from 2.1 to 2.8, e.g. from 2.3 to 2.8 for boron-free glasses and from 2.2 to 2.7 for boron containing glasses. In another nonlimiting embodiment of the present invention, the SiO2-RO difference of the glass composition ranges from 26.5 to 36.6 wt %, e.g. from 30.5 to 36.6 wt % for boron-free glasses and from 26.5 to 34.0 wt % for boron containing glasses.

The sum of SiO2+AI2O3 is another parameter that describes the compositional envelope of a given melt. Up to about an AI2O3 level of 14 to 15 wt %, AI2O3 is believed to be able to participate in the network formation with SiO2, and counteract the crystallization potential of RO that is always present. At higher AI2O3 levels, e.g. greater than 15 wt %, AI2O3 will begin to act much like RO and contribute to a rise of the crystallization potential of a given melt. Thus a lower value of SiO2 +AI2O3, which is indicative of a lower AI2O3 level for a glass composition of a given wt % of SiO2, will typically result in a lower crystallization potential, and a greater value of SiO2+AI2O3 will typically result in a higher crystallization potential for a given melt. In one nonlimiting embodiment of the present invention, the SiO2+AI2O3 sum of the glass composition ranges from 66.0 to 73.7 wt %, e.g. from 70.8 to 73.7 wt % for boron-free glasses and from 66.0 to 72.1 wt % for boron containing glasses.

Similarly with respect to SiO2/AI2O3 and based on the characteristics of the melt provided by the amount of AI2O3, an increasing ratio value would be indicative of a reduction in the amount of AI2O3 and/or an increase in the amount of SiO2 and would be accompanied by a reduction in the crystallization potential of the melt. Conversely, a decreasing ratio value would be accompanied by an increase in the crystallization potential of the melt. In one nonlimiting embodiment of the present invention, the SiO2/AI2O3 ratio of the glass composition ranges from 3.7 to 5.0, e.g. from 4.2 to 5.0 for boron-free glasses and from 3.7 to 4.9 for boron containing glasses.

As mentioned above, other mathematical relationships of ingredients of glass compositions, e.g. the AI2O3/CaO ratio, the AI2O3/ RO ratio, and the (SiO2+AI2O3)/(R2O+RO+B2O3) ratio may be developed to characterize a given melt. In one nonlimiting embodiment of the present invention, the value of the AI2O3/CaO ratio of the glass composition ranges from 0.5 to 0.6. In another nonlimiting embodiment of the present invention, the value of the AI2O3/ RO ratio of the glass composition ranges from 0.4 to 0.6, e.g. from 0.46 to 0.53 for boron-free glasses and from 0.46 to 0.56 for boron containing glasses. In still another nonlimiting embodiment of the present invention, the value of the (SiO2+AI2O3)/(R2O+RO+B2O3) ratio of the glass composition ranges from 2.0 to 3.0, e.g. from 2.3 to 3.0 for boron-free glasses and from 2.0 to 2.7 for boron containing glasses. Reference may be had to WO 01/32576 for additional discussion on the AI2O3/CaO ratio, and the (SiO2+AI2O3)/(R2O+RO+B2O3) ratio.

The discussion will now be directed to additives to the batch materials to alter the forming temperature, the liquidus temperature and the delta T. As previously discussed, boron is a material that is added to glass fiber compositions to reduce the forming temperature and the liquidus temperature. However, as discussed earlier, the inclusion of boron oxide results in the production of particulate emissions that, depending on the particulate level, may have to be removed from a melting furnace exhaust stream before being released into the environment. Although the amount of B2O3 can be as high as 10 wt % in an E-glass composition, in the present invention, the glass composition has no boron or a low boron content, i.e. has a B2O3 content in the range of 0 to 5.10 wt %. In other nonlimiting embodiments of the present invention, the glass fiber composition has no greater than 4 wt %, or no greater than 3 wt %, or no greater than 2 wt % B2O3. In another nonlimiting embodiment of the present invention, the glass composition is boron-free or essentially boron-free. As the term “essentially free” is used herein, the glass composition does not include an ingredient purposely added to the glass but found in the glass in trace amounts. In the practice of the invention, a glass having up to 0.05 wt % B2O3 is considered a boron free glass.

Further, as previously discussed, fluorine is a material added to glass fiber compositions as a flux, however, because of the environmental concerns it is preferred not to include fluorine. Nevertheless because equipment is available to remove the fluorine from the exhaust gases, the invention may be practiced using fluorine. In one nonlimiting embodiment of the present invention, the glass composition has low fluorine content, in other words, a fluorine content no greater than 0.30 wt %. In another nonlimiting embodiment, the glass composition is essentially fluorine free, i.e. it includes no more than a trace amount of fluorine, which is considered herein to be up to 0.05 wt %. In still another nonlimiting embodiment, the glass composition does not include any fluorine. Except where otherwise indicated, the glass fiber forming compositions disclosed and discussed herein are essentially fluorine free and/or do not include any fluorine.

Additional materials that can be added to the glass fiber composition to modify the melt properties, e.g. to reduce forming temperature and/or liquidus temperature of the glass include without limiting the glass compositions disclosed herein, are Li2O, Na2O, ZnO, TiO2, MnO and/or MnO2. Alkali oxides are network terminators and tend to effect the melt properties. K2O an alkali oxide is found in levels up to 0.60 wt % in commercial clays and is not normally added as a separate ingredient to the batch materials; however, in the practice of the invention it may be added as a separate material. In the practice of the invention alkali oxides up to 2.00 wt %, preferably 1 wt % are present in the glass of one embodiment of the invention. In the instance where K2O is present in the clay, the difference is usually made up by additions of Na2O and Li2O. Li2O is more effective in reducing the melt properties than Na2O. In one non-limiting embodiment of the present invention, the glass composition includes 0 to 1.0 wt % Li2O and/or 0 to 1.00 wt % Na2O and/or 0 to 1 wt % K2O. Non-alkali oxide ingredients usually employed to reduce the melt properties are ZnO, TiO2, MnO and/or MnO2 in amounts of about 0 to 1.5 wt % ZnO, 0 to 1.5 wt % TiO2, 0 to 3 wt % MnO and/or 0 to 3 wt % MnO2. It is believed that levels of these materials less than 0.05 wt % would be considered either tramp amounts or so low that they will not materially impact the glass melt properties. As a result, in another non-limiting embodiment, 0.05 to 1.5 wt % Li2O and/or 0.05 to 1.0 wt % Na2O and/or 0.05 to 1.0 wt % K2O and/or 0.05 to 1.5 wt % ZnO and/or 0.05 to 1.5 wt % TiO2 and/or 0.05 to 3 wt % MnO and/or 0.05 to 3 wt % MnO2 are included in the glass composition. In still another nonlimiting embodiment of the invention, the glass composition includes 0.2 to 1 wt % Li2O and/or 0.30 to 1.0 wt % Na2O and/or 0.30 to 1.0 wt % K2O and/or 0.2 to 1 wt % ZnO and/or 0.05 to 1.1 wt % TiO2 and/or up to 1 wt % MnO and/or up to 1 wt % MnO2.

As mentioned above, the ratio (SiO2+AI2O3)/(R2O+RO+B2O3) takes into account the wt % of the additions of B2O3, Na2O, K2O and Li2O that is (are) measured in the glass or batch materials regardless of the amount. Tramp amounts of these materials in the glass and/or batch are to be used to determine the value of the ratio. If any or all of the additions of B2O3, Na2O, K2O and Li2O are not determined to be present in the glass and/or batch, the value of zero is used for that ingredient in determining the value of the ratio. For example but not limiting to the invention, if Na2O, K2O and Li2O are present and B2O3 is not, the ratio (SiO2+AI2O3)/(R2O+RO+B2O3) becomes (SiO2+AI2O3)/(R2O+RO). If none of the ingredients B2O3, Na2O, K2O and Li2O are determined to be present, the ratio becomes (SiO2+AI2O3)/RO. In the claims when the ratio (SiO2+AI2O3)/(R2O+RO+B2O3) is recited in a claim, if the ingredient is not recited in the claim, it is not used to determine the value of the ratio even though it is determined to be present in a glass covered by the claim. The preceding discussion is applicable to the other mathematical relationships, e.g. but not limiting thereto (R2O+RO+B2O3).

It should be appreciated that glass fiber compositions. can include other oxides that are present as tramp materials such as BaO, ZrO2, SrO and Cr2O3, which are usually present in amounts of up to 0.1 wt %.

Further, it should be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as FeO, Fe2O3 and SO3, are useful during production of the glass, but their residual amounts in the glass can vary and typically have minimal, if any, material effect on the properties of the glass product. In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents, e.g. 0 to 0.5 wt % for SO3, FeO and Fe2O3.

Shown in Table 1 are several examples of glass compositions of an embodiment of the invention, which relates to the use of clay having high K2O and low TiO2 levels in glass batch materials and to glass compositions having high levels K2O and low levels of TiO2. K2O and TiO2 can be added to the batch materials but are not economically removed from the clays used as batch material. As can be appreciated by those skilled in the art of glass melting and as discussed above, high K2O levels, e.g. up to 0.70 wt % in the glass raises the forming temperature by as much as about 7 to 10° C. in relation to a glass made from clay that introduces 0.10 wt % K2O. One embodiment of the present invention relates to an improved E-type glass having low weight percent B2O3, a forming temperature no greater than 1230° C., preferably no greater than 1222° C. and a delta T of at least 50° C. and preferably up to 65° C. The following are the main constituents in wt % based on the total weight percent of the final glass composition. The K2O and TiO2 listed in the ranges below for commercial glasses may or may not be added to the batch as separate ingredient. If the K2O and TiO2 are not added, it is expected that they would be present in the clay in varying wt % depending on the geographical location of the clay. Although the K2O and TiO2 would be present in the clay, the invention contemplates separate additions of K2O and/or TiO2 to be within the ranges listed below.

In those instances when the clay has high wt % of K2O, e.g. 0.60 wt %, it is necessary to counteract the effect of the K2O. More particularly, the K2O increases the forming temperature; therefore, the ingredients in the batch materials have to be modified so as to maintain a low forming temperature, e.g. below 1240° C. In one embodiment of the invention such a glass is as follows.

most preferred
broad rangepreferred rangerange
SiO2 (wt %)  52 to 60  54 to 59  55 to 58
Al2O3 (wt %)  8 to 16  11 to 14  12 to 14
CaO (wt %)  21 to 26  22 to 25  23 to 25
MgO (wt %)  1 to 5  1 to 4  2 to 3
K2O (wt %)up to 1.000.30 to 1.000.30 to 0.80
Na2O (wt %)up to 1.000.30 to 1.000.30 to 0.90
K2O + Na20 (wt %)0.70 to 2.000.80 to 1.50.90 to 1.20
B2O3 (wt %)1.00 to 3.501.10 to 2.001.20 to 1.50
Fe2O3 (wt %)0.10 to 0.500.15 to 0.450.20 to 0.40
TiO2up to 2.0Up to 1.5Up to 1.3

The range provided for B2O3 is not limiting to the invention, and it is recommended the level of boron be adjusted to meet local environmental regulations. As such, the invention may be practiced having levels of B2O3 up to 3.5 wt %.

The glasses of the invention are further defined by one or more of the following relationships:

broad rangepreferred range
wt % of CaO and MgO  26 to 28 wt %  26 to 27.70 wt %
(“RO”)
SiO2/CaO 2.10 to 2.80 2.20 to 2.70
SiO2/RO 1.90 to 2.55 1.90 to 2.40
SiO2/Al2O3 3.70 to 5.00 3.7 to 4.90
Al2O3/CaO 0.45 to 0.65 0.50 to 0.60
SiO2 + Al2O3  66 to 73.70 wt %  66 to 72.10 wt %
SiO2 − RO26.56 to 36.60 wt %26.50 to 34 wt %
Al2O3/RO 0.40 to 0.60 0.46 to 0.56
R2O + RO + B2O328.00 to 32.00 wt %28.00 to 31.00 wt %
(SiO2 + Al2O3)/(R2O + RO + 2.00 to 3.00 2.00 to 2.70
B2O3)

where R2O is equal to the sum of Na2O +K2O.

Table 1 contains experimental samples A-E and illustrative samples F and G of glass compositions incorporating features of the invention. The ranges for the glass compositions listed on Table 1 are the minimum and maximum values for the glass compositions recited on Table 1, and for examples A-E, and F and G. More particularly, Table 1 provides the following glass compositions. A glass composition having the following ingredients:

SiO255.00 to 58percent by weight;
Al2O312.00 to 14.00percent by weight;
CaO23.80 to 24.80percent by weight;
MgO2.50 to 3.00percent by weight;
TiO2up to 0.60percent by weight;
Na2O0.40 to 0.50percent by weight;
K2O0.40 to 0.60percent by weight;
Na2O + K2O0.85 to 1.50percent by weight;
Fe2O30.20 to 0.40percent by weight;
B2O31.25 to 1.55percent by weight;

the following relationship of ingredients

RO26.25 to 27.60 wt %
SiO2/CaO 2.20 to 2.40
SiO2/RO 2.00 to 2.20
SiO2/Al2O3 3.95 to 4.70
Al2O3/CaO 0.50 to 0.60
SiO2 + Al2O369.00 to 70.50 wt %
SiO2 − RO28.00 to 31.00 wt %
Al2O3/RO 0.45 to 0.55
R2O + RO + B2O328.90 to 30.00 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.25 to 2.45

where R2O is equal to the sum of Na2O +K2O has a log3 forming temperature in the range of 1210 to 1225° C. and ΔT is in the range of 52 to 65° C.

Another glass composition defined by Examples A-E of Table 1 has the following ingredients

SiO255.60 to 57.60percent by weight;
Al2O312.35 to 13.94percent by weight;
CaO24.40 to 24.80percent by weight;
MgO2.55 to 2.80percent by weight;
TiO20.55percent by weight;
Na2O0.45percent by weight;
K2O0.45 to 0.58percent by weight;
Na2O + K2O0.90 to 1.03percent by weight;
Fe2O30.25 to 0.38percent by weight;
B2O31.30 to 1.50percent by weight, and

the following relationships:

RO26.95 to 27.56 wt %
SiO2/CaO 2.25 to 2.29
SiO2/RO 2.02 to 2.14
SiO2/Al2O3 4.00 to 4.66
Al2O3/CaO 0.51 to 0.56
SiO2 + Al2O369.18 to 69.95 wt %
SiO2 − RO28.04 to 30.65 wt %
Al2O3/RO 0.46 to 0.51
R2O + RO + B2O329.15 to 29.89 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.31 to 2.40

where R2O is equal to the sum of Na2O+K2O. The glass composition has a log3 forming temperature in the range of 1156 to 1164° C. and ΔT is in the range of 54 to 65° C.

Other glass compositions identified by Examples F and G of Table 1 have the following ingredients

SiO256.70 to 57.85percent by weight;
Al2O312.55 to 13.67percent by weight;
CaO23.87 to 24.45percent by weight;
MgO2.55 to 2.62percent by weight;
TiO20.05 to 0.34percent by weight;
Na2O0.44 to 0.455percent by weight;
K2O0.45 to 0.51percent by weight;
Na2O + K2O0.90 to 1.03percent by weight;
Fe2O30.30 to 0.40percent by weight;
B2O31.30 to 1.50percent by weight, and

the following relationships:

RO26.49 to 27.00 wt %
SiO2/CaO 2.37 to 2.38
SiO2/RO 2.10 to 2.14
SiO2/Al2O3 4.15 to 4.61
Al2O3/CaO 0.51 to 0.57
SiO2 + Al2O370.37 to 70.44 wt %
SiO2 − RO30.21 to 30.85 wt %
Al2O3/RO 0.46 to 0.52
R2O + RO + B2O328.94 to 29.20 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.41 to 2.43

where R2O is equal to the sum of Na2O+K2O. The glasses have a log3 forming temperature in the range of 1218 to 1219° C. and ΔT is in the range of 52 to 58° C.

The experimental or laboratory examples or samples on Table 1 discussed above and on Tables 2 to 19 to be discussed below, unless indicated otherwise, were prepared from certified or reagent grade oxides (e.g., pure silica or calcia). Examples F and G on Table 1 and examples H and I on Table 2 are illustrative examples and were not prepared in the following manner. The batch size for each example was 1000 grams. The individual batch ingredients were weighed out, combined and placed in a tightly sealed glass jar or plastic container. The sealed jar or container was then placed in a paint shaker for 15 minutes or in a tubular mixer for 25 minutes to effectively mix the ingredients. A portion of the batch was then placed into a platinum crucible, filling no more than {fraction (3/4)} of its volume. The crucible was then placed in a furnace and heated at 1427° C. (2600° F.) for 15 minutes. The remaining batch was then added to the hot crucible and heated at 1427° C. (2600° F.) for 15 to 30 minutes. The furnace temperature was then raised to 1482° C. (2700° F.) and held there for 2 hours. The molten glass was then fritted in water and dried. The fritted samples were reheated to a temperature of 1482° C. (2700° F.) and held at that temperature for 2 hours. The molten glass was then fritted again in water and dried.

The forming temperature, i.e. the glass temperature at a viscosity of 1000 poise, was determined by ASTM method C965-81, and the liquidus temperature by ASTM method C829-81. The log 3 forming temperature of the compositions reported in Tables 1-20 were determined by a comparison of the glass against physical standards supplied by the National Institute of Standards and Testing (NIST). In the Tables, the majority of the reported log 3 forming temperatures is based on comparison to NIST 710A. Several of the reported log 3 forming temperatures are originally based on NIST 717A which uses a borosilicate standard; in those instances the values were converted to correspond to NIST 710A. Therefore all the log3 forming temperatures are considered to based on NIST 710A.

Selected samples had ingredients added that would be found in the clays used in the batch material. Such as K2O, TiO2, calcium fluoride, SrO and/or Cr2O3.

The weight percent of the constituents of the compositions shown in Tables 1-19 except for Examples F to I are based on the weight percent of each constituent in the batch. It is believed that the batch weight percent is generally about the same as the weight percent of the melted sample, except for glass batch materials that volatilize during melting, e.g. boron, fluorine and moisture absorbing materials. In the case of boron, it is believed that the weight percent of B2O3 in a laboratory sample will be 10 to 16 weight percent less than the weight percent of B2O3 in the batch composition, the precise loss depending on the composition and melting conditions. In the case of fluorine, it is believed that the weight percent of fluorine in a laboratory test sample will be about 50 percent less than the weightpercent of fluorine in the batch composition, the precise loss depending on the composition and melting conditions. In the case of CaO, CaO has an certified ignition loss 3-5 wt % (an average of 4 wt %). The determination of the wt % of the batch materials for the samples listed on Tables 1-19 except for Examples F to 1, through an oversight, did not take into account the ignition loss. Therefore in practicing the invention, this fact should be taken into account.

Because the 4wt % error is minimal, the recitation of the wt % of CaO recited in the claims covering the embodiments of the glass compositions listed on Tables 1-19 does not take into account the ignition loss. Table 20 has production samples; the analysis of the ingredients of the examples on Table 20 were measured using XRF analysis.

As can be appreciated by those skilled in the art of converting data from laboratory melt sample to data used to prepare batch materials for commercial glass production, the melting and fining conditions of the commercial furnace to be used to melt and fine the glass has to be taken into consideration. It is believed that glass fiber compositions made from commercial grade materials and melted under conventional operating conditions will have similar batch and melt weight percents as discussed above, with the precise loss depending, in part, on the furnace operating temperature, through-put and quality of commercial batch materials. The amount of boron and fluorine reported in the tables takes into consideration the expected loss of these materials and represents the expected amount of the material in the glass composition. It should further be appreciated that the glass compositions disclosed herein can also include small amounts of other materials, for example melting and refining aids, tramp materials or impurities. For example and without limiting the present invention, melting and fining aids, such as SO3are useful during production of the glass, but their residual amounts in the glass can vary and have no material effect on the properties of the glass product. In addition, small amounts of the additives discussed above can enter the glass composition as tramp materials or impurities included in the raw materials of the main constituents.

With reference to Tables 1-20, in each column of each Table, the upper portion of the column lists the wt % of the ingredients in the glass composition based on the batch materials as was discussed above. The middle portion of the column lists the mathematical relationship of the ingredients discussed above for the particular glass composition in the same column to obtain the thermal properties listed in the bottom portion of the column e.g. forming temperature, liquidus temperature and delta T (except for certain compositions of Table 20 which is discussed below). Table 20 lists production glasses. The amount of each constituent of the commercial compositions shown in the Table 20 is the weight percent in the glass. The weight percent for the B2O3 was determined using Neutron Transmission analysis techniques and the weight percent for the remaining constituents was determined using X-ray fluorescence analysis (also referred to as “XRF analysis”), all of which are well known to those skilled in the art.

Tables 2 through 19 include, but are not limited to glass compositions disclosed in U.S. patent application Ser. No.09/980,248, filed Nov. 28, 2001, in the name of Frederick T. Wallenberger for “Glass Fiber Compositions” (hereinafter “U.S. patent application Ser. No. 09/980,248”); in PCT International Application No. PCT/US01/27451, filed Sep. 5, 2001, in the name of Frederick T. Wallenberger for “Glass Fiber Forming Compositions” (hereinafter “USPCT No. 01/27451”); and in International Application No. PCT/US00/14155. U.S. patent application Ser. No. 09/980248 and International Application No. PCT/US00/14155 are jointly referred to as “U.S. patent application Ser. No. 09/980248 Combined”.

U.S. patent application Ser. No. 09/980,248 Combined and USPCT No. 01/27451 discloses base composition for the low boron glass fibers that are suitable for textiles and glass fiber reinforcements, that may be used in the practice of the present invention. In general, the base compositions of U.S. patent application Ser. No. 09/980248 Combined and USPCT No. 01/27451 include the following main constituents in weight percent ranges based on the total weight of the final glass composition with the exception that USPCT No. 01/27451 glass compositions are boron free.

broad rangepreferred rangemost preferred range
SiO2 (wt %)  52 to 6252 to 6153 to 59
Na2O (wt %)  0 to 2up to 1.5up to 1
CaO (wt %)  16 to 2520 to 2522 to 24
Al2O3 (wt %)  8 to 1611 to 1412 to 14
Fe2O3 (wt %)0.05 to 0.80up to 0.5up to 0.4
K2O (wt %)  0 to 2Up to 1up to 0.1
B2O3(wt %)  1 to 5 1 to 3.5 1 to 2.5

In one embodiment the glass comparison of U.S. patent application Ser. No. 09/980,248 Combined, the glass composition can include on or more of the following materials in the following amounts.

broad rangepreferred range
Li2O (wt %)0.05 to 1.50.2 to 1
ZnO (wt %)0.05 to 1.50.2 to 1
MnO (wt %)0.05 to 3up to 1
MnO2 (wt %)0.05 to 3up to 1

For a complete discussion of the glass compositions disclosed in U.S. patent application Ser. No. 09/980,248 Combined, and disclosed in USPCT No. 01/27451, reference should be made thereto.

As discussed above the examples of Table 1 incorporate features of one embodiment of the invention, a low boron glass composition (see the upper portion of the columns on Table 1) having a forming temperature below 1240° C., more preferably below 1225° C. and a delta T of greater than 50° C.(see the lower portion of the columns on Table 1). The examples of Tables 1-20 include another feature of the invention, mathematical relationship of the ingredients in the glass composition (see middle portion of the columns on Tables 1-20) to provide a forming temperature below 1240° C. and a delta T of greater than 50° C. (see the lower portion of the columns on Tables 1-20). The mathematical relationship of the ingredients of the glass compositions on Table 1 were discussed above. Tables 2-19 include, but are not limited to examples of glass compositions disclosed in U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451. Additional examples within the scope of the inventions of U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451 are included herein. For example, but not a complete relationship, examples 188-236 are selected from U.S. patent application Ser. No. 09/980,248 Combined and examples 7-24, 43-50,78-185, and 219-267 are selected from USPCT No. 01/27451. Examples A-E, 25, 30-32, 60-75 are examples, among others, presented by this application. The examples identified as selected from U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451 and those added to the Tables by the instant disclosure are not complete. For a complete comparison reference may be had to U.S. patent application Ser. No. 09/980,248 Combined and/or in USPCT No. 01/27451.

For a better appreciation of the invention the samples on Tables 2-19 are categorized according to the following types of glass compositions.

  • Type-1 Glasses boron-free (Table 2)
  • Type-2 Glasses up to about 5.10 wt % B2O3 (Tables 3-11)
  • Type-3 Glasses boron-free with lithium oxide (Tables 12 and 13)
  • Type-4 Glasses boron-free with lithium and zinc oxide (Tables 14 and 15)
  • Type-5 Glasses boron-free with zinc oxide (Table 16)
  • Type-6 Glasses up to 5 wt % B2O3 with lithium oxide (Tables 17 and 18)
  • Type-7 Glasses miscellaneous glass (Table 19)
    Table 20, as previously discussed includes production glasses.

Table 2 (Type 1 Glasses) includes glass compositions of a quaternary system that includes SiO2 in the range of 57-60 wt %, preferably in the range of 57.25-59.50 wt % and more preferable in the range of 57.40-59.10; AI2O3 in the range of 12-14 wt %, preferably in the range of 12-13.50 wt % and more preferably in the range of 12.15-13.45 wt %; CaO in the range of 23-25 wt %, preferable in the range of 23.50-24.50 wt % and more preferable in the range of 23.70-24.20 wt %, and MgO in the range of 2-3 wt %, preferably in the range of 2.25-2.75 wt % and more preferably in the range of 2.50-2.60 wt %. The glass compositions of Table 2 further include TiO2 in the range of up to 1.25 wt %, preferably in the range of 0.25-1.20 wt % and more preferably in the range of 0.50-1.15 wt %; Na2O in the range of 0.75-1.25, preferably in the range of 0.75-1.00 wt % and more preferably in the range of 0.85-0.95 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably 0.10-0.50 wt % and more preferably in the range of 0.30-0.40 wt %. The compositions of Table 2 are boron free. Compositions 1-6 of Table 2 further include TiO2 in the range of 1.00-1.25 wt %, preferably in the range of 1.00-1.20 wt % and more preferably in the range of 1.05-1.15 wt %; Na2O in the range of 0.75-1.25, preferably in the range of 0.75-1.00 wt % and more preferably in the range of 0.85-0.95 wt %; and Fe2O3 in the range of up to 0.35 wt %, preferably 0.10-0.30 wt % and more preferably in the range of 0.20-0.30 wt %. Compositions H and I include TiO2 in the range of 0-0.9 wt %, preferably in the range of 0.25-0.75 wt % and more preferably in the range of 0.50-0.6 wt %; Na2O in the range of 0.75-1.25, preferably in the range of 0.75-1.00 wt % and more preferably in the range of 0.85-0.95 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably 0.10-0.40 wt % and more preferably in the range of 0.30-0.40 wt %.

A glass composition having the ingredients of Table 2 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1 240° C. and a delta T of greater than 50° C., e.g.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  26 to 28 wt %26.00 to 27.25 wt %
SiO2/CaO2.10 to 2.80 2.30 to 2.80
SiO2/RO1.90 to 2.55 1.90 to 2.40
SiO2/Al2O33.70 to 5.00; 4.20 to 5.00
Al2O3/CaO0.40 to 0.75 0.50 to 0.60
SiO2 + Al2O3  66 to 73.7 wt %70.80 to 73.7 wt %
R2O + RO  27 to 28.15 wt27.15 to 20 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.0 to 3.0 2.30 to 3.00
SiO2 − RO26.5 to 36.6 wt %30.50 to 36.60 wt %
Al2O3/RO 0.4 to 0.6 0.46 to 0.56

The Type 1 glass compositions are not expected to have any Li2O or K2O, therefore R2O is equal to the wt % of Na2O.

As can be appreciated, Table 2 also provides ranges for the ingredients and the relationships. For example, but not limiting to the invention, the ranges for the ingredients of the glass compositions listed on Table 2 are as follows:

SiO257.45 to 59.05percent by weight;
Al2O312.20 to 13.40percent by weight;
CaO23.75 to 24.35percent by weight;
MgO2.55percent by weight;
TiO21.10percent by weight;
Na2O30.90percent by weight, and
Fe2O30.25percent by weight.

The range of the mathematical relationships of the ingredients from Table 2 for the glass compositions listed on Table 2 is found in Table 21 in the column entitled “Type 1 Glasses”. The glasses on Table 2 have a log3 forming temperature in the range of 1232 to 1240° C. and a ΔT in the range of 58 to 74° C.

Table 2 also provides ranges for the Examples 1-6. More particularly, from Table 2 Example 1-6 glass compositions have the following ingredients and ranges:

SiO257.45 to 59.05percent by weight;
Al2O312.20 to 13.68percent by weight;
CaO23.75 to 24.50percent by weight;
MgO2.55 to 2.58percent by weight;
TiO20.55 to 1.10percent by weight;
Na2O30.90 to 0.91percent by weight, and
Fe2O30.25 to 0.35percent by weight.

The range of the mathematical relationship of the ingredients from Table 2 for the glass compositions of Examples 1-6 can be found on Table 21 under Type 1 Glasses. The glass compositions of Examples 1-6 have a log3 forming temperature in the range of 1232 to 1240° C. and a ΔT in the range of 58 to 74° C.

Further, Table 2 provides ranges for the Examples H and I. More particularly, from Table 2 Examples H and I glass compositions have the following ingredients and ranges:

SiO257.60 to 58.18percent by weight;
Al2O313.55 to 13.68percent by weight;
CaO23.75 to 24.50percent by weight;
MgO2.55 to 2.58percent by weight;
TiO20.55percent by weight;
Na2O30.90 to 0.91percent by weight, and
Fe2O30.35percent by weight.

the ranges for the mathematical relationships of the ingredients from Table 2 are as follows:

RO26.33 to 27.05 wt %
SiO2/CaO 2.35 to 2.45
SiO2/RO 2.13 to 2.20
SiO2/Al2O3 4.25
Al2O3/CaO 0.55 to 0.58
SiO2 + Al2O371.15 to 71.86 wt %
SiO2 − RO30.55 to 31.85 wt %
Al2O3/RO 0.50 to 0.52
R2O + RO27.24 to 27.95 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.55 to 2.64

The glass compositions of Examples H and I have a log3 forming temperature in the range of 1238 to 1240° C. and a ΔT of 55° C.

Tables 3-11 (Type 2 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 50-60 wt %, preferably in the range of 52.25-59.00 wt % and more preferable in the range of 52.90-58.00 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11-14 wt % and more preferably in the range of 12-14 wt %; CaO in the range of 21-26 wt %, preferable in the range of 21.50-25.50 wt % and more preferable in the range of 22-25 wt %, and MgO in the range of 1-4 wt %, preferably in the range of 1.25-3.50 wt % and more preferably in the range of 1.45-3.25 wt %. The compositions of Tables 3-11 include B2O3 in an amount within the range of greater than 0 to 5.10 wt %, e.g. 0.90-5.10 wt %. The compositions of Table 3-11 further contemplate TiO2 in the range of 0.25-1.25 wt %, more likely in the range of 0.40-1.20 wt % and most likely in the range of 0.45-1.15 wt %; Na2O in the range of 0.25-1.25, preferably in the range of 0.35-1.00 wt % and more preferably in the range of 0.40-0.95 wt %; K2O expected in amounts up to 0.60 wt %; and Fe2O3 in the range of up to 0.50 wt %, preferably up to −0.45 wt % and more preferably up to 0.40 wt %. Other ingredients included in the glass compositions of Tables 3-11 but not limited thereto are fluorine in amounts up to 0.50 wt %; SrO in amounts up to 0.15 wt % and Cr2O3 in amounts up to 0.15 wt %.

A glass composition having ingredients of Tables 3-11 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  24 to 29 wt %24.75 to 27.60 wt %
SiO2/CaO2.10 to 2.80 2.15 to 2.75
SiO2/RO1.95 to 2.55 1.90 to 2.40
SiO2/Al2O33.70 to 5.00 3.70 to 4.90
Al2O3/CaO0.45 to 0.65 0.45 to 0.65
SiO2 + Al2O3  66 to 73.7 wt %  66 to 72.1 wt %
R2O + RO + B2O327.5 to 34 wt %  28 to 33 wt %
(SiO2 + Al2O3)/(R2O + RO +2.00 to 3.00 2.00 to 2.70
B2O3)
SiO2 − RO26.5 to 36.6 wt % 26.5 to 34 wt %
Al2O3/RO0.40 to 0.60 0.46 to 0.56

Type 2 glasses of Tables 3-11 do not consider Li2O as an ingredient; therefore for Tables 3-11, R2O is equal to the sum of the wt % of K2O and Na2O. If one of the ingredients is not present in the glass it is given a 0 wt %. For the glasses listed on each of the Tables 3,4,6,7,10 and 11, only the addition of Na2O is considered; therefore for the glasses on the individual Tables 3,4,6,7,10 and 11, R2O is equal to the wt % of Na2O. For the glasses listed on the individual Tables 5,8 and 9, Na2O and K2O are considered; therefore for the glasses on the individual Tables 5,8 and 9, R2O is equal to the sum of the wt % of Na2O and K2O.

As can be appreciated, each of the Tables 3-11 provides ranges for the ingredients and the relationships. For example and not limiting to the invention, Tables 3-11 provide glass compositions having the following ingredients in the following ranges:

SiO253.00 to 57.75percent by weight;
Al2O312.20 to 14percent by weight;
CaO22.25 to 24.95percent by weight;
MgO1.50 to 3.00percent by weight;
TiO20.50 to 1.10percent by weight;
Na2O0.45 to 0.90percent by weight;
K2O0 to 0.38percent by weight;
Fe2O30 to 0.30percent by weight;
B2O31.30 to 5.02percent by weight;
F0 to 0.50percent by weight;
SrO0 to 0.13percent by weight, and
Cr2O30 to 0.13percent by weight.

The mathematical relationship of the ingredients is found on Table 21 in the column entitled “Type 2 Glasses”.

Table 3 provides glass compositions having ingredients in the following ranges:

SiO256.00 to 56.65percent by weight;
Al2O313.05 to 13.60percent by weight;
CaO23.50 to 24.25percent by weight;
MgO2.50 to 2.55percent by weight;
TiO20.50 to 1.10percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight, and
B2O32.00percent by weight.

The ranges for the mathematical relationships of ingredients of the glass compositions on Table 3 from Table 3 are as follows:

RO26.05 to 26.75 wt %
SiO2/CaO 2.31 to 2.41
SiO2/RO 2.09 to 2.17
SiO2/Al2O3 4.12 to 4.28
Al2O3/CaO 0.56 to 0.57
SiO2 + Al2O369.60 to 69.95 wt %
SiO2 − RO29.25 to 30.60 wt %
Al2O3/RO 0.50 to 0.52
R2O + RO + B2O328.95 to 29.65 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.35 to 2.41

The glass compositions of Table 3 have a log3 forming temperature in the range of 1200 to 1220° C. and a ΔT is in the range of 56 to 69° C.

Table 4 provides glass compositions having Ingredients in the following ranges:

SiO2 is56.25 to 57.75percent by weight;
Al2O3 is12.20 to 13.20percent by weight;
CaO23.75 to 24.25percent by weight;
MgO2.55percent by weight;
TiO21.10percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight, and
B2O31.30 to 1.40percent by weight.

The ranges for the mathematical relationships of the ingredients for the glass compositions of Table 4 from Table 4 are as follows:

RO26.30 to 26.80 wt %
SiO2/CaO 2.32 to 2.43
SiO2/RO 2.10 to 2.20
SiO2/Al2O3 4.26 to 4.73
Al2O3/CaO 0.51 to 0.56
SiO2 + Al2O369.45 to 69.95 wt %
SiO2 − RO29.45 to 31.45 wt %
Al2O3/RO 0.46 to 0.50
R2O + RO + B2O328.50 to 29.00 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.39 to 2.45.

The glass compositions of Table 4 have a log3 forming temperature in the range of 1200 to 1218° C. and a ΔT in the range of 55° C. to 70° C.

The glass compositions of Table 5 have the following ingredients in the following ranges:

SiO255.19 to 56.00percent by weight;
Al2O313.10 to 13.80percent by weight;
CaO24.50 to 24.67percent by weight;
MgO2.55 to 2.95percent by weight;
TiO21.10percent by weight;
Na2O0.45percent by weight;
K2O0.45 to 0.58percent by weight;
Fe2O30.25 to 0.38percent by weight, and
B2O31.30percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 5 from Table 5 are as follows:

RO27.08 to 27.45 wt %
SiO2/CaO 2.25 to 2.28
SiO2/RO 2.01 to 2.07
SiO2/Al2O3 4.01 to 4.19
Al2O3/CaO 0.53 to 0.56
SiO2 + Al2O368.75 to 69.37 wt %
SiO2 − RO27.78 to 28.92 wt %
Al2O3/RO 0.48 to 0.51
R2O + RO + B2O329.28 to 29.74 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.31 to 2.37

The glass compositions of Table 5 have a log3 forming temperature in the range of 1210 to 1222° C. and a ΔT in the range of 53 to79° C.

Table 6 provides glass compositions having ingredients in the following ranges:

SiO256.15 to 57.60percent by weight;
Al2O313.25 to 13.95percent by weight;
CaO24.40 to 24.95percent by weight;
MgO2.55percent by weight;
TiO20.55percent by weight;
Na2O0.90percent by weight;
Fe2O30.25 to 0.35percent by weight, and
B2O31.30percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 6 from Table 6 are as follows:

RO26.95 to 27.50 wt %
SiO2/CaO 2.25 to 2.36
SiO2/RO 2.04 to 2.14
SiO2/Al2O3 4.01 to 4.66
Al2O3/CaO 0.54 to 0.57
SiO2 + Al2O369.50 to 69.99 wt %
SiO2 − RO28.65 to 30.65 wt %
Al2O3/RO 0.46 to 0.51
R2O + RO + B2O329.15 to 29.70 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.34 to 2.40.

The glass compositions of Table 6 have a log3 forming temperature in the range of 1211 to 1220° C. and a ΔT is in the range of 52 to 66° C.

Table 7 provides glass compositions having ingredients in the following ranges:

SiO255.25 to 56.15percent by weight;
Al2O313.05 to 13.30percent by weight;
CaO23.00 to 24.20percent by weight;
MgO2.55percent by weight;
TiO20.25 to 1.25percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight; and
B2O33.00percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 7 from Table 7 are as follows:

RO25.55 to 26.75 wt %
SiO2/CaO 2.28 to 2.44
SiO2/RO 2.07 to 2.20
SiO2/Al2O3 4.15 to 4.30
Al2O3/CaO 0.55 to 0.56
SiO2 + Al2O368.20 to 69.20 wt %
SiO2 − RO28.45 to 30.60 wt %
Al2O3/RO 0.50 to 0.51
R2O + RO + B2O329.45 to 30.65 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.24 to 2.35

The glass compositions of Table 7 have a log3 forming temperature in the range of 1193 to 1212° C. and a ΔT is in the range of 64 to 90° C.

Table 8 provides glass compositions having ingredients in the following ranges:

SiO254.12 to 55.25percent by weight;
Al2O313.20 to 13.40percent by weight;
CaO24.20 to 24.55percent by weight;
MgO2.55percent by weight;
TiO20.55percent by weight;
Na2O0.45 to 0.50percent by weight;
K2O0.45 to 0.55percent by weight;
Fe2O30.25 to 0.28percent by weight;
B2O33.00percent by weight;
Fup to 0.20percent by weight, and
SrOup to 0.12percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 8 from Table 8 are as follows:

RO26.75 to 27.55 wt %
SiO2/CaO 2.20 to 2.28
SiO2/RO 1.96 to 2.07
SiO2/Al2O3 4.06 to 4.15
Al2O3/CaO 0.54 to 0.55
SiO2 + Al2O367.55 to 68.55 wt %
SiO2 − RO26.57 to 28.30 wt %
Al2O3/RO 0.49 to 0.50
R2O + RO + B2O330.65 to 31.40 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.14 to 2.22

The glass compositions of Table 8 have a log3 forming temperature in the range of 1190 to 1204° C. and a ΔT is in the range of 55 to 83° C.

Table 9 provides glass compositions having Ingredients in the following ranges:

SiO253.00 to 53.50percent by weight;
Al2O313.10 to 14.00percent by weight;
CaO24.00percent by weight;
MgO1.25 to 2.50percent by weight;
TiO20.50percent by weight;
Na2O0.90percent by weight;
K2O0.37percent by weight;
Fe2O30.10percent by weight;
B2O34.93 to 5.02percent by weight;
F0.50percent by weight;
SrO0.13percent by weight, and
Cr2O30.13percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 9 from Table 9 are as follows:

RO25.50 to 26.50 wt %
SiO2/CaO 2.21 to 2.23
SiO2/RO 2.00 to 2.10
SiO2/Al2O3 3.82 to 4.05
Al2O3/CaO 0.55 to 0.58
SiO2 + Al2O366.10 to 67.50 wt %
SiO2 − RO26.50 to 28.00 wt %
Al2O3/RO 0.49 to 0.55
R2O + RO + B2O331.70 to 32.79 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.02 to 2.13

The glass compositions of Table 9 have a log3 forming temperature in the range of 1167 to 1177 and a ΔT is in the range of 57 to 69° C.

Table 10 provides glass compositions having ingredients in the following ranges:

SiO255.40 to 57.75percent by weight;
Al2O312.20 to 13.80percent by weight;
CaO22.25 to 24.85percent by weight;
MgO2.05 to 2.60percent by weight;
TiO20.50 to 1.10percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight, and
B2O31.00 to 3.00percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 10 from Table 10 are as follows:

RO26.80 to 27.35 wt %
SiO2/CaO 2.23 to 2.55
SiO2/RO 2.05 to 2.27
SiO2/Al2O3 4.04 to 4.69
Al2O3/CaO 0.51 to 0.59
SiO2 + Al2O369.00 to 70.95 wt %
SiO2 − RO28.05 to 32.55 wt %
Al2O3/RO 0.46 to 0.53
R2O + RO + B2O328.15 to 30.25 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.28 to 2.67

The glass compositions of Table 10 have a log3 forming temperature in the range of 1202 to 1240° C. and a ΔT is in the range of 53 to 100° C.

The glass compositions listed on Table 10 and the glasses within the scope of the embodiment of Table 10 have a forming temperature in the range of 1202 to 1240° C. It should be noted that the measured delta T for Example 91 was 34° C.; it is believed that this is a measuring error the liquidus temperature because the glass composition of Example 90 has similar ingredients, a lower liquidus temperature and a delta T of 100° C. Therefore the delta T of Example 91 is considered to be about 90° C. The preferred glass compositions from Table 10 are those that provide the forming temperature range 1202 to 1219° C. and a delta T greater than 5° C., more particularly Examples 78-91.

The glass compositions of Examples 78-91 of Table 10 from Table 10 have the following ingredients in the following ranges:

SiO255.40 to 56.65percent by weight;
Al2O313.05 to 13.80percent by weight;
CaO23.00 to 24.85percent by weight;
MgO2.50 to 2.55percent by weight;
TiO20.50 to 1.10percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight, and
B2O32.00 to 3.00percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Examples 78-91 of Table 10 from Table 10 are as follows:

RO25.55 to 27.35 wt %
SiO2/CaO 2.23 to 2.44
SiO2/RO 2.03 to 2.20
SiO2/Al2O3 4.06 to 4.34
Al2O3/CaO 0.54 to 0.57
SiO2 + Al2O368.95 to 69.95 wt %
SiO2 − RO28.05 to 30.60 wt %
Al2O3/RO 0.49 to 0.53
R2O + RO + B2O328.95 to 30.25 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.28 to 2.41

The glass composition of Examples 78-91 have a log3 forming temperature in the range of 1202 to 1219° C. and a ΔT is in the range of 53 to 100° C.

The glass compositions of Table 11 from Table 11 have the following ingredients in the following ranges:

SiO256.10 to 57.75percent by weight;
Al2O312.20 to 13.38percent by weight;
CaO23.75 to 24.42percent by weight;
MgO2.55percent by weight;
TiO20.55 to 1.10percent by weight;
Na2O0.90percent by weight;
Fe2O30.25percent by weight; and
B2O31.30 to 1.40percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 11 from Table 11 are as follows:

RO26.30 to 26.97 wt %
SiO2/CaO 2.30 to 2.43
SiO2/RO 2.08 to 2.20
SiO2/Al2O3 4.19 to 4.73
Al2O3/CaO 0.51 to 0.54
SiO2 + Al2O369.48 to 69.95 wt %
SiO2 − RO29.13 to 31.45 wt %
Al2O3/RO 0.46 to 0.50
R2O + RO + B2O328.60 to 29.17 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.38 to 2.44

The glass compositions of Table 11 have a log3 forming temperature in the range of 1215 to 1218° C. and a ΔT in the range of 63° C. to 65° C.

Tables 12 and 13 (Type 3 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55-62 wt %, preferably in the range of 56-61 wt % and more preferably in the range of 57.5-61 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11-14 wt % and more preferably in the range of 11.75-13.75 wt %; CaO in the range of 20-26 wt %, preferable in the range of 21.50-25.00 wt % and more preferable in the range of 21.75-24.50 wt %, and MgO in the range of 1-4 wt %, preferably in the range of 1.35-3.50 wt % and more preferably in the range of 1.60-3.25 wt %. The compositions of Tables 12 and 13 are boron free. The compositions of Tables 12 and 13 contemplate a TiO2 in the range of 0.25-1.75 wt %, more likely in the range of 0.40-1.60 wt % and most likely more preferably in the range of 0.45-1.55 wt %; Na2O in amounts up to 0.75 wt %, preferably in amounts up to 0.70 wt % and more preferably in amounts up to 0.65 wt %; Li2O in amounts in the range of 0.10 to 1.25 wt %, preferably in the range of 0.20 to 1.10 wt %, and more preferably in the range of 0.30 to 1.00 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably up to 0.45 wt % and more preferably up to 0.30 wt %.

A glass composition having ingredients of Tables 12 and 13 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1 240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)23.50 to 27.50 wt %23.75 to 27.00 wt %
SiO2/CaO 2.10 to 2.80 2.30 to 2.80
SiO2/RO 1.90 to 2.55 2.10 to 2.55
SiO2/Al2O3 3.70 to 5.00 4.20 to 5.00
Al2O3/CaO 0.45 to 0.65 0.45 to 0.60
SiO2 + Al2O3  66 to 73.7 wt % 70.8 to 73.7 wt %
R2O + RO24.75 to 28 wt %  25 to 27.75 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.00 to 3.00 2.30 to 3.00
SiO2 − RO 26.5 to 36.6 wt %30.50 to 36.6 wt %
Al2O3/RO 0.40 to 0.60 0.46 to 0.53

The Type 3 Glasses do not consider the addition of K2O; therefore for Type 3 Glasses R2O is equal to the sum of the wt % of Na2O and Li2O.

As can be appreciated, each of the Tables 12 and 13 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 12 and 13 from Tables 12 and 13 have the following ingredients in the following ranges:

SiO257.65 to 60.75percent by weight;
Al2O312.00 to 13.64percent by weight;
CaO22 to 24.155percent by weight;
MgO1.70 to 3.40percent by weight;
TiO20.50 to 1.50percent by weight;
Na2O0.30 to 0.60percent by weight;
Li2O0.30 to 1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 12 and 13 from Tables 12 and 13 are on Table 21 under the column entitled “Type 3 Glasses”. The glass compositions of Tables 12 and 13 have a log3 forming temperature in the range of 1205 to 1240° C., and a ΔT in the range of 50 to 100° C.

The glass compositions of Table 12 from Table 12 have the following ingredients in the following ranges:

SiO258.25 to 59.97percent by weight;
Al2O312.19 to 13.64percent by weight;
CaO22.04 to 23.65percent by weight;
MgO2.50 to 3.12percent by weight;
TiO20.50 to 1.50percent by weight;
Na2Oup to 0.30percent by weight;
Li2O0.90 to 0.91percent by weight, and
Fe2O30.20 to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 12 are as follows:

RO24.94 to 26.20 wt %
SiO2/CaO 2.47 to 2.72
SiO2/RO 2.23 to 2.40
SiO2/Al2O3 4.31 to 4.92
Al2O3/CaO 0.55 to 0.59
SiO2 + Al2O371.55 to 73.03 wt %
SiO2 − RO32.15 to 34.91 wt %
Al2O3/RO 0.48 to 0.52
R2O + RO25.84 to 27.10 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.64 to 2.79

The glass compositions of Table 12 have a log3 forming temperature in the range of 1211° C. and to 1218° C., and a ΔT in the range of 56 to 68° C.

The glass compositions of Table 13 from Table 13 have the following ingredients in the following ranges:

SiO257.65 to 60.75percent by weight;
Al2O312.00 to 13.40percent by weight;
CaO22.00 to 24.15percent by weight;
MgO1.70 to 3.12percent by weight;
TiO20.50 to 1.50percent by weight;
Na2O0.45 to 0.90percent by weight;
Li2O0.45 to 1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 13 from Table 13 is as follows:

RO24.25 to 26.70 wt %
SiO2/CaO 2.39 to 2.72
SiO2/RO 2.16 to 2.51
SiO2/Al2O3 4.30 to 4.92
Al2O3/CaO 0.50 to 0.59
SiO2 + Al2O371.05 to 73.67 wt %
SiO2 − RO31.35 to 36.56 wt %
Al2O3/RO 0.47 to 0.55
R2O + RO24.91 to 27.90 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.30 to 2.96

The glass compositions have a log3 forming temperature in the range of 1205 to1240° C. and a ΔT are in the range of 50 to 101° C.

The glass compositions listed on Table 13 and the glasses within the scope of the embodiment of Table 13 have a forming temperature in the range of 1205 to 1240° C. and a delta T in the range of 50-100° C.; however the preferred glass compositions from Table 13 are those that provide the forming temperature range of 1205 to 1220° C. and more preferably in the range of 1205-1218° C. more particularly Examples 123, 124, 125, 127-132, 147, 153, 155, 157, 160 and 161 with the appropriate delta T, e.g. 50° C. or greater.

The glass compositions of Examples 123, 124, 125, 127-132, 147, 153, 155, 157, 160 and 161 from Table 13 have the following ingredients in the following ranges:

SiO257.65 to 60.33percent by weight;
Al2O312.22 to 13.40percent by weight;
CaO22.00 to 24.15percent by weight;
MgO2.30 to 3.40percent by weight;
TiO20.50 to 1.50percent by weight;
Na2Oup to 0.45percent by weight;
Li2O0.45 to 1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of Examples 123, 124, 125, 127-132, 147, 153, 155, 157, 160 and 161 from Table 13 are as follows:

RO24.84 to 26.70 wt %
SiO2/CaO 2.39 to 2.72
SiO2/RO 2.16 to 2.42
SiO2/Al2O3 4.30 to 4.92
Al2O3/CaO 0.52 to 0.59
SiO2 + Al2O371.05 to 72.80 wt %
SiO2 − RO31.35 to 35.37 wt %
Al2O3/RO 0.47 to 0.52
R2O + RO25.74 to 27.60 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.30 to 2.81

The glass compositions have a log3 forming temperature in the range of 1205 to 1220° C. and in the range of 1205 to 1218° C., and a ΔT in the range of equal to and greater than 50° C. and equal to and less than 60° C.

The selection of the above examples is made based on the low forming temperature. As can be appreciated, if a high delta T is of interest then Examples 135-141, for example, would be of interest because they have a delta T in the range of 77-100° C.

The glass compositions of Examples 135-141 from Table 13 have the following ingredients in the following ranges:

SiO259.55 to 60.57percent by weight;
Al2O312.25 to 13.10percent by weight;
CaO22.31 to 23.85percent by weight;
MgO1.70 to 3.10percent by weight;
Na2Oup to 0.30percent by weight
TiO21.10percent by weight, and
Li2Oup to 0.60percent by weight.

The ranges for the mathematical relationships of the ingredients of Examples 135-141 from Table 13 is as follows:

RO24.01 to 25.95 wt %
SiO2/CaO 2.50 to 2.71
SiO2/RO 2.29 to 2.52
SiO2/Al2O3 4.62 to 4.88
Al2O3/CaO 0.52 to 0.59
SiO2 + Al2O371.80 to 73.67 wt %
SiO2 − RO33.60 to 36.56 wt %
Al2O3/RO 0.47 to 0.55
R2O + RO24.91 to 26.85 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.67 to 2.96

The glass compositions have a log3 forming temperature in the range of 1234 to 1240° C., and a ΔT is in the range of 61 to 100° C.

Tables 14 and 15 (Type 4 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55-62 wt %, preferably in the range of 56-61 wt % and more preferable in the range of 57-60 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11-14 wt % and more preferably in the range of 12-13.75 wt %; CaO in the range of 21-26 wt %, preferable in the range of 21.50-25.00 wt % and more preferable in the range of 21.75-24.50 wt %, and MgO in the range of 1-3.25 wt %, preferably in the range of 1.50-3.00 wt % and more preferably in the range of 1.75-2.75 wt %. The compositions of Tables 14 and 15 are boron free. The compositions of Tables 14 and 15 contemplate TiO2 in the range of 0.25-1.75 wt %, more likely in the range of 0.40-1.50 wt % and most likely in the range of 0.45-1.25 wt %; Li2O in amounts in the range of 0.25 to 1.25 wt %, preferably in the range of 0.30 to 1.10 wt %, and more preferably in the range of 0.40 to 1.00 wt %, ZnO in amounts in the range of 0.25 to 1.25 wt %, preferably in the range of 0.30 to 1.15 wt %, and more preferably in the range of 0.40 to 1.10 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably up to 0.35 wt % and more preferably up to 0.30 wt %.

A glass composition having ingredients of Tables 14 and 15 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  24 to 28 wt %25.25 to 27.00 wt %
SiO2/CaO2.10 to 2.80 2.30 to 2.60
SiO2/RO1.90 to 2.55 2.10 to 2.55
SiO2/Al2O33.70 to 5.00 4.20 to 5.00
Al2O3/CaO0.45 to 0.65 0.50 to 0.60
SiO2 + Al2O3  68 to 73.7 wt % 70.8 to 72 wt %
R2O + RO  25 to 30 wt % 26.0 to 28 wt %
(SiO2 + Al2O3)/(R2O + RO)2.00 to 3.00 2.30 to 3.00
SiO2 − RO26.5 to 36.60 wt % 30.5 to 36.60 wt %
Al2O3/RO0.40 to 0.60 0.46 to 0.53

The Type 4 Glasses are shown only to have Li2O; therefore for Type 4 Glasses R2O is equal to the wt % of Li2O.

As can be appreciated, each of the Tables 14 and 15 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 14 and 15 from Tables 14 and 15 have the following ingredients in the following ranges:

SiO257.35 to 59.618.30percent by weight;
Al2O312.16 to 13.63percent by weight;
CaO22.85 to 24.22percent by weight;
MgO 1.90 to 2.55percent by weight;
TiO2 0.50 to 1.10percent by weight;
Li2O 0.45 to 0.90percent by weight;
ZnO 0.45 to 1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

in the range of 1195 to 1229° C., and a ΔT is in the range of 54 to 71° C. The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 14 and 15 are found on Table 21 under the column entitled “Type 4 Glasses”. The glass compositions have a log3 forming temperature.

The glass compositions of Table 14 from Table 14 have the following ingredients in the following ranges:

SiO258.00 to 58.30percent by weight;
Al2O313.03 to 13.33percent by weight;
CaO22.85 to 23.84percent by weight;
MgO2.50 to 2.55percent by weight;
TiO20.50 to 1.10percent by weight;
Li2O0.90percent by weight;
ZnO1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 14 from Table 14 are as follows:

RO25.40 to 26.34 wt %
SiO2/CaO 2.43 to 2.54
SiO2/RO 2.20 to 2.29
SiO2/Al2O3 4.36 to 4.47
Al2O3/CaO 0.55 to 0.58
SiO2 + Al2O371.13 to 71.58 wt %
SiO2 − RO31.66 to 32.75 wt %
Al2O3/RO 0.49 to 0.52
R2O + RO26.30 to 27.24 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.61 to 2.71

The glass compositions have a log3 forming temperature in the range of 1204 to 1213° C., and a ΔT in the range of 56 to 71° C.

The glass compositions of Table 15 from Table 15 have the following ingredients in the following ranges:

SiO257.35 to 59.61percent by weight;
Al2O312.16 to 13.63percent by weight;
CaO23.14 to 24.22percent by weight;
MgO1.90 to 2.55percent by weight;
TiO20.50 to 1.10percent by weight;
Li2O0.45 to 0.90percent by weight;
ZnO0.45 to 1.00percent by weight, and
Fe2O3up to 0.25percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 15 from Table 15 are as follows:

RO25.64 to 26.60 wt %
SiO2/CaO 2.41 to 2.54
SiO2/RO 2.18 to 2.29
SiO2/Al2O3 4.26 to 4.90
Al2O3/CaO 0.50 to 0.59
SiO2 + Al2O370.55 to 71.77 wt %
SiO2 − RO31.15 to 33.61 wt %
Al2O3/RO 0.47 to 0.53
R2O + RO26.45 to 27.50 wt %
(SiO2 + Al2O3)/(R2O + RO) 2.60 to 2.71

The glass compositions of Table 15 have a log3 forming temperature in the range of 1195 to 1229° C., and a ΔT in the range of 54 to 59° C.

Table 16 (Type 5 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 55-62 wt %, preferably in the range of 56-61 wt % and more preferable in the range of 58-60 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11.00-13.5 wt % and more preferably in the range of 11.75-13.25 wt %; CaO in the range of 21-25 wt %, preferable in the range of 21.25-24.00 wt % and more preferable in the range of 21.25-23.00 wt %, and MgO in the range of 1-4.00 wt %, preferably in the range of 1.25-3.50 wt % and more preferably in the range of 1.50-3.50 wt %. The compositions of Table 16 are boron free. The compositions of Table 16 contemplate TiO2 in the range of 0.50-2.00 wt %, more likely in the range of 0.50-1.50 wt % and more preferably in the range of 0.75-1.25 wt %; Na2O in amounts in no greater than 2.00 wt %; preferably no greater than 1.50 wt %, and more preferably no greater than 1.25 wt %; ZnO in amounts in the range of 0.50 to 3.00 wt %, preferably in the range of 0.50 to 2.75 wt %, and more preferably in the range of 0.75 to 2.50 wt %, and Fe2O3 in the range of up to 0.50 wt %, preferably in the range of up to 0.35 wt % and more preferably in the range of up to 0.30 wt %.

A glass composition having ingredients of Table 16 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1 240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  23 to 28 wt % 24.0 to 27.0 wt %
SiO2/CaO2.10 to 2.80 2.30 to 2.80
SiO2/RO1.90 to 2.55 2.10 to 2.55
SiO2/Al2O33.70 to 5.00 4.20 to 5.00
Al2O3/CaO0.45 to 0.65 0.45 to 0.60
SiO2 + Al2O3  66 to 73.7 wt % 70.8 to 73.7 wt %
R2O + RO  25 to 28 wt % 26.0 to 27.0 wt %
(SiO2 + Al2O3)/(R2O + RO)2.00 to 3.00 2.30 to 3.0
SiO2 − RO  30 to 39 wt %31.50 to 37. wt %
Al2O3/RO0.40 to 0.60 0.46 to 0.53

Type 5 Glasses were considered having Na2O; therefore R2O is equal to the sum of Na2O in wt %.

As can be appreciated, Table 16 provides ranges for the ingredients and the relationships. More particularly, the glass compositions of Tablel6 from Table 16 have the following ingredients in the following ranges:

SiO258.70 to 59.00percent by weight;
Al2O311.90 to 12.00percent by weight;
CaO22.40 to 22.50percent by weight;
MgO3.40percent by weight;
TiO21.00percent by weight;
Na2O0.90percent by weight;
ZnO1.00 to 1.50percent by weight, and
Fe2O3up to 0.20percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Table 16 from Table 16 are on Table 21 under the column entitled “Type 5 Glasses”. The glass compositions of Table 16 have a log3 forming temperature in the range of 1231 to 1234° C., and a ΔT in the range of 50 to 59° C.

Tables 17 and 18 (Type 6 Glasses) include glass compositions of a quaternary system that includes SiO2 in the range of 50-62 wt %, preferably in the range of 52-61 wt % and more preferable in the range of 53.50-60.25 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11.00-14.00 wt % and more preferably in the range of 11.90-13.75 wt %; CaO in the range of 21-26 wt %, preferable in the range of 22.00-25.00 wt % and more preferable in the range of 22.50-24.25 wt %, and MgO in the range of 1-4.00 wt %, preferably in the range of 1.50-3.00 wt % and more preferably in the range of 2.25-2.75 wt %. The compositions of Tables 17 and 18 have B2O3 in the range of 0.50-5.00 wt %, preferably in the range of 0.50-4.00 and more preferably in the range of 0.75-3.25 wt %. The compositions of Tables 17 and 18 contemplate further include TiO2 in the range of 0.25-2.00 wt %, more likely in the range of 0.35-1.50 wt % and most likely in the range of 0.40-1.25 wt %; Na2O in amounts no greater than 1.00 wt %; preferably no greater than 0.90 wt %, and more preferably no greater than 0.75 wt %; K2O in amounts no greater than 0.50 wt %; preferably no greater than 0.35 wt %, and more preferably no greater than 0.20 wt %; Li2O in amounts in the range of 0.10 to 1.25 wt %, preferably in the range of 0.20 to 1.10 wt %, and more preferably in the range of 0.25 to 1.00 wt %, and Fe2O3 in the range of 0.10-0.50 wt %, preferably in the range of 0.15-0.50 wt % and more preferably in the range of 0.20-0.40 wt %.

A glass composition having ingredients of Tables 17 and 18 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  24 to 28 wt % 25.0 to 27.20 wt %
SiO2/CaO2.10 to 2.80 2.20 to 2.70
SiO2/RO1.90 to 2.55 1.90 to 2.40
SiO2/Al2O33.50 to 5.00 4.00 to 5.00
Al2O3/CaO0.50 to 0.60 0.50 to 0.60
SiO2 + Al2O3  66 to 73.7 wt %  67 to 72.1 wt %
R2O + RO + B2O3  25 to 32 wt %26.50 to 32 wt %
(SiO2 + Al2O3)/(R2O + RO +2.00 to 3.25 2.30 to 3.00
B2O3)
SiO2 − RO26.5 to 36.6 wt %  27 to 36.6 wt %
Al2O3/RO0.40 to 0.60 0.46 to 0.56

Type 6 Glasses of Tables 17and18 included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O. Individual Table 17 includes Li2O and Na2O; therefore R2O for Table 17 is equal to the sum in wt % of Li2O and Na2O. Individual Table 18 includes Li2O, K2O and Na2O; therefore R2O for Table 18 is equal to the sum in wt % of Li2O, K2O and Na2O.

As can be appreciated, Tables 17 and 18 provide ranges for the ingredients and the relationships. More particularly, the glass compositions of Tables 17 and 18 have the following ingredients in the following ranges:

SiO254.60 to 59.53percent by weight;
Al2O312.16 to 13.63percent by weight;
CaO22.87 to 24.05percent by weight;
MgO2.00 to 2.55percent by weight;
TiO20.49 to 1.10percent by weight;
Na2O0 to 0.60percent by weight;
K2O0 to 0.10percent by weight;
Li2O0.30 to 0.91percent by weight;
Fe2O30.23 to 0.30percent by weight, and
B2O30.90 to 3.00percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 and 18 are on Table 21 under the column entitled “Type 6 Glasses”. The glass compositions of Table 17 and 18 have a log3 forming temperature in the range of 1187 to 1239° C., and a ΔT in the range of 50 to 142° C.

The glass compositions of Table 17 have the following ingredients in the following ranges:

SiO257.60 to 58.50percent by weight;
Al2O312.76 to 13.43percent by weight;
CaO23.40 to 23.84percent by weight;
MgO2.50percent by weight;
TiO20.50percent by weight;
Na2Oup to 0.60percent by weight;
Li2O0.90percent by weight;
Fe2O30.23percent by weight, and
B2O31.00 to 1.20percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 are as follows:

RO25.90 to 26.34 wt %
SiO2/CaO 2.42 to 2.48
SiO2/RO 2.19 to 2.24
SiO2/Al2O3 4.30 to 4.47
Al2O3/CaO 0.54 to 0.57
SiO2 + Al2O370.83 to 71.47 wt %
SiO2 − RO31.26 to 32.39 wt %
Al2O3/RO 0.49 to 0.52
R2O + RO + B2O327.80 to 28.44 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.49 to 2.57

Type 6 Glasses of Table 17 included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.

The glass compositions of Table 17 have a log3 forming temperature in the range of 1192 to 1198° C., and a ΔT in the range of 55 to 63° C.

The glass compositions of Table 18 have the following ingredients in the following ranges:

SiO254.60 to 59.53percent by weight;
Al2O312.16 to 13.63percent by weight;
CaO22.93 to 24.05percent by weight;
MgO2.00 to 2.55percent by weight;
TiO20.49 to 1.10percent by weight;
Na2Oup to 0.60percent by weight;
K2Oup to 0.10percent by weight;
Li2O0.30 to 0.91percent by weight;
Fe2O30.23 to 0.35percent by weight, and
B2O30.60 to 3.00percent by weight.

The ranges for the mathematical relationships of the ingredients of the glass compositions of Tables 17 are as follows:

RO25.80 to 26.60 wt %
SiO2/CaO 2.22 to 2.66
SiO2/RO 2.01 to 2.39
SiO2/Al2O3 4.09 to 4.90
Al2O3/CaO 0.51 to 0.59
SiO2 + Al2O367.95 to 72.05 wt %
SiO2 − RO27.50 to 33.84 wt %
Al2O3/RO 0.46 to 0.53
R2O + RO + B2O326.70 to 31.10 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.18 to 2.68

The glass compositions of Table 18 have a log3 forming temperature in the range of 1187 to 1239° C., and a ΔT in the range of 50 to 42° C.

The glass compositions listed on Table 18 and the glasses within the scope of the embodiment of Table 18 have a forming temperature in the range of 1187 to 1239° C. and a delta T in the range of 50-142° C.; however the preferred glass compositions from Table 18 are those that provide the forming temperature range 1187 to 1220° C. (Examples 188-213, 215-229, 213-235, 238-240, 242-260 and 262-262) and more preferably in the range of 1187-1205° C. (Examples 188-191, 194, 195, 198, 200, 201, 202-205, 208, 209, 211-213, 215-219, 221-223, 225-229, 233-235, 239, 242, 257 and 260).

A glass composition having the ingredients in the ranges mentioned above for Table 18 and having the following relationships will provide glass compositions having a log3 forming temperature in the range of 1187 to 1220° C., and a ΔT is in the range of 50 to 139° C.:

RO25.80 to 26.60 wt %
SiO2/CaO 2.22 to 2.66
SiO2/RO 2.01 to 2.39
SiO2/Al2O3 4.09 to 4.87
Al2O3/CaO 0.51 to 0.59
SiO2 + Al2O367.95 to 72.05 wt %
SiO2 − RO27.50 to 33.84 wt %
Al2O3/RO 0.46 to 0.53
R2O + RO + B2O326.70 to 31.10 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.18 to 2.68

The glass compositions from Table 18 having a log3 forming temperature in the range of 1187 to 1205° C., and a ΔT in the range of 50 to 124° C. have the following ingredients and the following ranges:

SiO257.60 to 59.21percent by weight;
Al2O312.16 to 13.63percent by weight;
CaO22.87 to 24.06percent by weight;
MgO2.36 to 2.50percent by weight;
TiO20.49 to 1.10percent by weight;
Na2Oup to 0.30percent by weight;
K2Oup to 0.09percent by weight;
Li2O0.70 to 0.90percent by weight;
Fe2O30.23 to 0.29percent by weight, and
B2O31.00 to 1.20percent by weight;

And the following relationships:

RO25.23 to 26.54 wt %
SiO2/CaO 2.40 to 2.57
SiO2/RO 2.17 to 2.32
SiO2/Al2O3 4.26 to 4.87
Al2O3/CaO 0.52 to 0.59
SiO2 + Al2O370.63 to 71.73 wt %
SiO2 − RO31.06 to 33.61 wt %
Al2O3/RO 0.47 to 0.53
R2O + RO + B2O327.23 to 28.64 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.47 to 2.63

The selection of these examples is made based on the low forming temperature. Further, examples 266-268 are glass compositions that have a low forming temperature with 0.30 wt % Li2O. Examples 265-268 define a range of ingredients and relationship of the ingredients to provide a low Li2O containing glass with low forming temperature. As can be appreciated and as previously discussed, if a high delta T is of interest then Examples from Table 18 have a high delta T, e.g. above 75° C. may be selected to define glass compositions.

Table 19 (Type 7 Misc. Glasses) includes glass compositions of a quaternary system that includes SiO2 in the range of 56-60 wt %, preferably in the range of 57-59 wt % and more preferable in the range of 57.50-59 wt %; AI2O3 in the range of 10-14 wt %, preferably in the range of 11.00-14.00 wt % and more preferably in the range of 11.50-14.00 wt %; CaO in the range of 21-25 wt %, preferable in the range of 22.00-24.00 wt % and more preferable in the range of 22.50-24.00 wt %, and MgO in the range of 2.00-4.00 wt %, preferably in the range of 2.00-3.00 wt % and more preferably in the range of 2.25-2.75 wt %. The compositions of Table 19 include B2O3 in the range of 0-1.50 wt %, preferably in the range of 0-1.25 wt % and more preferably in the range of 0-1.10 wt %. The compositions of Table 19 contemplates further includes TiO2 in the range of 0.25-1.50 wt %, more likely preferably in the range of 0.25-1.35 wt % and most likely in the range of 0.40-1.25 wt %; Na2O in amounts no greater than 1.25 wt %; preferably no greater than 1.10 wt %, and more preferably no greater than 1.00 wt %; ZnO in amounts no greater than 0.50 wt %; preferably no greater than 0.40 wt %, and more preferably no greater than 0.35 wt %; MnO in amounts no greater than 4.00 wt %; preferably no greater than 3.50 wt %, and more preferably no greater than 3.25 wt %; MnO2 in amounts no greater than 4.00 wt %; preferably no greater than 3.50 wt %, and more preferably no greater than 3.25 wt %, and Fe2O3 in the range of 0.10-0.50 wt %, preferably in the range of 0.15-0.50 wt % and more preferably in the range of 0.20-0.40 wt %.

A glass composition having ingredients of Tables 19 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature below 1240° C. and a delta T of greater than 50° C.:

RelationshipBroad RangePreferred Range
RO (CaO + MgO)  24 to 27 wt %25.00 to 26.50 wt % SiO2/
CaO 2.10 to 2.80 2.20 to 2.70
SiO2/RO 1.90 to 2.55 1.90 to 2.40
SiO2/Al2O3 3.70 to 5.00 3.70 to 4.90
Al2O3/CaO 0.45 to 0.65 0.55 to 0.60
SiO2 + Al2O3  66 to 73.7 wt %  66 to 72.1 wt %
R2O + RO + B2O3  25 to 28 wt %25.75 to 27.50 wt %
(SiO2 + Al2O3)/(R2O + 2.00 to 3.00 2.00 to 2.75
RO + B2O3)
SiO2 − RO26.50 to 36.6 wt % 26.5 to 34.00 wt %
Al2O3/RO 0.40 to 0.60 0.46 to 0.56

The Misc. Glasses included Li2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O and Na2O.

Table 19 provides the following ranges for the following ingredients:

SiO257.72 to 58.70percent by weight;
Al2O311.88 to 13.35percent by weight;
CaO22.80 to 23.50percent by weight;
MgO2.43 to 2.50percent by weight;
TiO20.50 to 1.10percent by weight;
Na2O30.87-0.90percent by weight;
Li2O0 to 0.30percent by weight;
ZnO0 to 0.30percent by weight;
Fe2O30.22-0.25percent by weight;
MnO0.30 to 3.00percent by weight;
MnO20 to 3.00percent by weight, and
B2O30 to 1.00percent by weight.

The relationships for the ingredients of the glass compositions on Table 19 are as follows:

RO25.23 to 26.00 wt %
SiO2/CaO 2.49 to 2.54
SiO2/RO 2.25 to 2.29
SiO2/Al2O3 4.40 to 4.90
Al2O3/CaO 0.52 to 0.57
SiO2 + Al2O369.52 to 72.05 wt %
SiO2 − RO32.40 to 32.70 wt %
Al2O3/RO 0.47 to 0.51
R2O + RO + B2O326.10 to 27.30 wt %
(SiO2 + Al2O3)/(R2O + RO + B2O3) 2.59 to 2.74

The glass compositions have a log3 forming temperature of in the range of 1219 to 1241° C., and a ΔT in the range of 52 to 76° C.

Table 20 (Production Glasses) Table 20 is a representation of commercial glasses having embodiments of the invention similar to the embodiment of the glass compositions of Table 4. The glass compositions are of a quaternary system that includes SiO2 in the range of 55.97-57.07 wt %; AI2O3 in the range of 12.68-12.86 wt %; CaO in the range of 23.91-24.69 wt % and MgO in the range of 2.42-2.60 wt %. The compositions of Table 20 include B2O3 in the range of 1.15-1.70 wt %; TiO2 in the range of 0.94-1.09 wt %; Na2O in the range of 0.87-0.93 wt %; K2O in the range of greater than 0.050-0.070 wt %; SrO in the range of 0.040-0.050 wt %; Cr2O3 in the range of 0.002-0.008 wt %; SO3 in the range of 0.018-0.032 wt %, and Fe2O3 in the range of 0.255-0.278 wt %.

A glass composition having ingredients of Tables 20 within the above ranges and at least one of the following relationships provides a glass composition having a forming temperature in the range of 1203-1217° C. and a delta T in the range of 55-83° C. Several of the glass compositions do not have the forming and liquidus temperatures, and the delta T. The glass compositions without the temperatures and delta T were glass compositions made between glass compositions whose forming temperature, liquidus temperature and delta T were measured. As indicated by the position on the Table which is in general in chronological order, it is expected that the glass compositions not measured would have temperature performances similar to those that were measured. The mathematical relationships of the ingredients of the glass compositions on Table 20 are listed on Table 22 in the column entitled “Production Glasses (contain boron)”. The R2O from the listed Production Glasses is equal to the sum in wt % of Li2O and Na2O.

As can now be appreciated, a range for each of the ingredients of the glass compositions of Types 1 and 2 glasses (Tables 2-11) can be determined from Tables. More particularly, Tables 1 and 2 provide a quaternary system including SiO2, AI203, CaO and MqO and the ingredients of the glass having the relationship as shown in Table 22 under the column entitled “Types 1 & 2 Glasses”. Types 1 & 2 Glasses included K2O and Na2O: therefore R2O is equal to the sum in wt % of K2O and Na2Q.

The glass compositions having the following ingredients in the following ranges has a log3 forming temperature in the range of 1167 to 1240° C. and a ΔT in the range of 50 to 100° C.:

SiO253.00 to 59.05percent by weight;
Al2O312.20 to 14.00percent by weight;
CaO22.25 to 24.95percent by weight, and
MgO1.50 to 3.00percent by weight, and

the composition may further include:

TiO20.50 to 1.10percent by weight;
Na2O0.45 to 0.90percent by weight;
K2O0 to 0.58percent by weight;
Fe2O30 to 0.50percent by weight, and
B2O30 to 5.02percent by weight.

Further as can be appreciated, a range for each of the ingredients for Type 3-6 glasses on Tables 12-19 can be determined by selecting the lowest and highest values to define the range for an ingredient and/or relationship on Tables 12-19. More particularly Tables 12-19 provide glass compositions having a quaternary system including SiO2, AI2O3, CaO and Mgo with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 3-6 Glasses”. Types 3-6 Glasses included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.

The glass composition having the following ingredients in the following ranges has a log3 forming temperature in the range of 1187 to 1240° C. and a delta T in the range of 50 to 142° C.:

SiO254.60 to 60.75percent by weight;
Al2O311.90 to 13.64percent by weight;
CaO22.00 to 24.22percent by weight, and
MgO 1.90 to 3.40percent by weight, and

the composition may further include:

TiO20.49 to 1.50percent by weight;
Na2O0 to 0.90percent by weight;
K2O0 to 0.10percent by weight;
ZnO0.45 to 1.50percent by weight;
Li2O0.30 to 1.00percent by weight;
Fe2O30 to 0.35percent by weight, and
B2O30 to 3.00percent by weight.

Still further as can be appreciated, a range for each of the ingredients for boron free glasses: Type 1 Glasses (Table 2), Type 3 Glasses (Tables 12 and 13); Type 4 Glasses (Tables 14 and 15); Type 5 Glasses (Table 16) and their relationship can be determined from Tables 2 and 12-16. More particularly, Tables 2 and 12-16 glass compositions having a quaternary system including SiO2, AI2O3, CaO and Mgo with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 1 & 3-5 Glasses”. Types 1 & 3-5 Glasses included Li2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O and Na2O. Further Types 1 3&5 Glasses are boron free, therefore the formula “R2O+RO+B2O3” becomes “R2O+RO”.

The glass compositions having the following ingredients in the following ranges has a log3 forming temperature in the range of 1195 to 1240° C. and a delta T in the range of 50 to 100° C.:

SiO257.45 to 60.75percent by weight;
Al2O312.00 to 13.68percent by weight;
CaO22.00 to 24.50percent by weight;
MgO 1.70 to 3.10percent by weight, and

the composition may further include:

TiO20.50 to 1.50percent by weight;
Na2O0 to 0.91percent by weight;
ZnO0 to 1.00percent by weight;
Li2O0 to 1.00percent by weight, and
Fe2O30 to 0.35percent by weight.

Still further as can be appreciated, a range for each of the ingredients for boron containing: Type 2 Glasses (Tables 3-11) and Type 6 Glasses (Tables 17 and 18) and their relationship can be determined from Tables 3-11, 17 and 18. More particularly, Tables 3-11, 17 and 18 glass compositions having a boron containing (for example up to 5.05 wt %) quaternary system including SiO2, AI2O3, CaO and MgO with the ingredients of the glass having the relationship shown on Table 22 under the column entitled “Types 2 & 6 Glasses”. Types 2 & 6 Glasses included Li2O, K2O and Na2O; therefore R2O is equal to the sum in wt % of Li2O, K2O and Na2O.

The glass compositions having the following ingredients in the following ranges has a log3 forming temperature in the range of 1167 to 1240° C. and a delta T in the range of 50 to 142° C.:

SiO253.00 to 59.53percent by weight;
Al2O312.00 to 14.00percent by weight;
CaO22.25 to 24.95percent by weight, and
MgO1.50 to 3.00percent by weight, and

the composition may further include:

TiO20.40 to 1.10percent by weight;
Na2O0 to 0.90percent by weight;
K2O0 to 0.30percent by weight;
F0 to 0.50percent by weight;
SrO0 to 0.13percent by weight;
Cr2O30 to 0.13percent by weight;
Li2O0 to 0.91percent by weight, and
Fe2O30 to 0.30percent by weight.

It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. For example, but not limiting thereto, one, two, three or more or all of the formulas discussed above setting forth the mathematical relationship of the ingredients may be used to identify properties of a glass composition. Based on the description of the embodiments of the invention, it can be appreciated that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications that are within the spirit and scope of the invention, as defined by the appended claims.

TABLE 1
Examples
Components (wt %)ABCDEFG
SiO255.6056.4555.7057.6056.3556.7057.85
Al2O313.5813.2513.9412.3513.4513.6712.55
CaO24.7624.7524.8024.4024.6523.8724.45
MgO2.802.552.552.552.552.622.55
TiO20.550.550.550.550.550.340.05
Na2O0.450.450.450.450.450.440.45
K2O0.580.450.450.450.450.510.45
Fe2O30.380.250.250.250.250.350.35
B2O31.301.301.301.301.301.501.30
RO (CaO + MgO)27.5627.3027.3526.9527.2026.4927.00
SiO2/CaO2.252.282.252.362.292.382.37
SiO2/RO2.022.072.042.142.072.142.14
SiO2/Al2O34.094.264.004.664.194.154.61
Al2O3/CaO0.550.540.560.510.550.570.51
SiO2 + Al2O369.1869.7069.6469.9569.8070.3770.44
R2O + RO + B2O329.8929.5029.5529.1529.4028.9429.20
(Si + Al)/(R2O + RO + B)2.312.362.362.402.372.432.41
SiO2 − RO28.0429.1528.3530.6529.1530.2130.85
Al2O3/RO0.490.490.510.460.490.520.46
Log3 FT, ° C.1213122012201221122112181219
Liquidus T, ° C.1159116011651164115611601167
Delta T, ° C.54605557655852

TABLE 2
Type 1 Glasses
Examples
Components (wt %)HI123456
SiO257.6058.1857.7557.4557.6558.0557.9559.05
Al2O313.5513.6813.2013.4013.4013.4013.2012.20
CaO24.5023.7524.2524.3524.1523.7524.0523.95
MgO2.552.582.552.552.552.552.552.55
TiO20.550.551.101.101.101.101.101.10
Na2O0.900.910.900.900.900.900.900.90
Fe2O30.350.350.250.250.250.250.250.25
B2O3
RO (CaO + MgO)27.0526.3326.8026.9026.7026.3026.6026.50
SiO2/CaO2.352.452.382.362.392.442.412.47
SiO2/RO2.132.202.152.142.162.212.182.23
SiO2/Al2O34.254.254.384.294.304.334.394.84
Al2O3/CaO0.550.580.540.550.560.560.550.51
SiO2 + Al2O371.1571.8670.9570.8571.0571.4571.1571.25
R2O + RO + B2O327.9527.2427.7027.8027.6027.2027.5027.40
(Si + Al)/(R2O + RO + B)2.552.642.562.552.572.632.592.60
SiO2 − RO30.5531.8530.9530.5530.9531.7531.3532.55
Al2O3/RO0.500.520.490.500.500.510.500.46
Log3 FT, ° C.12401238123212381240124012351239
Liquidus T, ° C.11851183116611651166116711641181
Delta T, ° C.5555667374737158

TABLE 3
Type 2 Glasses
Examples
Components (wt %)789101112
SiO256.0056.4056.3556.6556.2056.50
Al2O313.6013.4013.6013.0513.6013.20
CaO24.2524.0523.8523.5024.0523.50
MgO2.502.502.552.552.502.55
TiO20.500.500.501.100.501.10
Na2O0.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.25
B2O32.002.002.002.002.002.00
RO (CaO + MgO)26.7526.5526.4026.0526.5526.05
SiO2/CaO2.312.352.362.412.342.40
SiO2/RO2.092.122.132.172.122.17
SiO2/Al2O34.124.214.144.344.134.28
Al2O3/CaO0.560.560.570.560.570.56
SiO2 + Al2O369.6069.8069.9569.7069.8069.70
R2O + RO + B2O329.6529.4529.3028.9529.4528.95
(Si + Al)/(R2O + RO + B)2.352.372.392.412.372.41
SiO2 − RO29.2529.8529.9530.6029.6530.45
Al2O3/RO0.510.500.520.500.510.51
Log3 FT, ° C.121312161218121812191220
Liquidus T, ° C.113611431138113111361133
Delta T, ° C.595662696569

TABLE 4
Type 2 Glasses
Examples
Components (wt %)13141516171819202122
SiO256.2556.4556.7556.5056.7557.556.7557.7557.7557.75
Al2O313.213.2013.2013.2013.2012.213.212.212.212.2
CaO24.2524.2523.9524.0023.752423.9523.7523.7523.95
MgO2.552.552.552.552.552.552.552.552.552.55
TiO21.101.101.101.101.101.101.101.101.101.10
Na2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.250.250.250.250.25
B2O31.301.301.301.301.401.301.201.401.301.40
RO (CaO + MgO)26.8026.8026.5026.5526.3026.5526.5026.3026.3026.50
SiO2/CaO2.322.332.372.352.392.402.372.432.432.41
SiO2/RO2.102.112.142.132.162.172.142.202.202.18
SiO2/Al2O34.264.284.304.284.304.714.304.734.734.73
Al2O3/CaO0.540.540.550.550.560.510.550.510.510.51
SiO2 + Al2O369.4569.6569.9569.7069.9569.7069.9569.9569.9569.95
R2O + RO + B2O329.0029.0028.7028.7528.6028.7528.6028.6028.5028.80
(Si + Al)/(R2O + RO + B)2.392.402.442.422.452.422.452.452.452.43
SiO2 − RO29.4529.6530.2529.9530.4530.9530.2531.4531.4531.25
Al2O3/RO0.490.490.500.500.500.460.500.460.460.46
Log3 FT, ° C.1210121412151215121512161216121712171218
Liquidus T, ° C.1154115911541154116011521147115111471155
Delta T, ° C.56556161556469667063

TABLE 5
Type 2 Glasses
Examples
Components (wt %)23242526272829303132
SiO255.4055.4055.1955.4056.0555.8556.0055.9055.4055.19
Al2O313.6013.6013.5913.6013.1013.3813.3713.3713.8013.59
CaO24.5024.5024.5524.5024.5524.6724.5324.6324.5024.55
MgO2.952.952.862.952.752.552.552.552.752.86
TiO21.101.101.101.101.101.101.101.101.101.10
Na2O0.450.450.450.450.450.450.450.450.450.45
K2O0.450.450.580.450.450.450.450.450.450.58
Fe2O30.250.250.380.250.250.250.250.250.250.38
B2O31.301.301.301.301.301.301.301.301.301.30
RO (CaO + MgO)27.4527.4527.4127.4527.3027.2227.0827.1827.2527.41
SiO2/CaO2.262.262.252.262.282.262.282.272.262.25
SiO2/RO2.022.022.012.022.052.052.072.062.032.01
SiO2/Al2O34.074.074.064.074.284.174.194.184.014.06
Al2O3/CaO0.560.560.550.560.530.540.550.540.560.55
SiO2 + Al2O369.0069.0068.7869.0069.1569.2369.3769.2769.2068.78
R2O + RO + B2O329.6529.6529.7429.6529.5029.4229.2829.3829.4529.74
(Si + Al)/(R2O + RO + B)2.332.332.312.332.342.352.372.362.352.31
SiO2 − RO27.9527.9527.7827.9528.7528.6328.9228.7228.1527.78
Al2O3/RO0.500.500.500.500.480.490.490.490.510.50
Log3 FT, ° C.1210121112161217121812201221122112211222
Liquidus T, ° C.1157115111541167115611481157114211671154
Delta T, ° C.53606256627264795463

TABLE 6
Type 2 Glasses
Examples
Components (wt %)33343536373839404142
SiO256.6056.5056.5055.9557.6056.5056.4556.5056.5556.15
Al2O313.2513.4513.4513.9512.3513.4913.4813.4513.3513.35
CaO24.6024.5024.5024.5524.4024.4624.5224.5024.5524.95
MgO2.552.552.552.552.552.552.552.552.552.55
TiO20.550.550.550.550.550.550.550.550.550.55
Na2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.350.250.250.250.250.25
B2O31.301.301.301.301.301.301.301.301.301.30
RO (CaO + MgO)27.1527.0527.0527.1026.9527.0127.0727.0527.1027.50
SiO2/CaO2.302.312.312.282.362.312.302.312.302.25
SiO2/RO2.082.092.092.062.142.092.092.092.092.04
SiO2/Al2O34.274.204.204.014.664.194.194.204.244.21
Al2O3/CaO0.540.550.550.570.510.550.550.550.540.54
SiO2 + Al2O369.8569.9569.9569.9069.9569.9969.9369.9569.9069.50
R2O + RO + B2O329.3529.2529.2529.3029.1529.2129.2729.2529.3029.70
(Si + Al)/(R2O + RO + B)2.382.392.392.392.402.402.392.392.392.34
SiO2 − RO29.4529.4529.4528.8530.6529.4929.3829.4529.4528.65
Al2O3/RO0.490.500.500.510.460.500.500.500.490.49
Log3 FT, ° C.1211121212151216121612181219122012201220
Liquidus T, ° C.1153115811571162116411611158116011551154
Delta T, ° C.58545854525761606566

TABLE 7
Type 2 Glasses
Examples
Components (wt %)43444546474849505152
SiO255.5055.2555.2555.555.0055.7555.7555.7556.0056.15
Al2O313.2013.2013.3013.3013.2013.3013.2013.2013.3013.05
CaO23.5023.7524.2023.9524.0023.7023.2523.2523.4523.00
MgO2.552.552.552.552.552.552.552.552.552.55
TiO21.101.100.550.551.100.551.101.100.551.10
Na2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.250.250.250.250.25
B2O33.003.003.003.003.003.003.003.003.003.00
RO (CaO + MgO)26.0526.3026.7526.5026.5526.2525.8025.8026.0025.55
SiO2/CaO2.362.332.282.322.292.352.402.402.392.44
SiO2/RO2.132.102.072.092.072.122.162.162.152.20
SiO2/Al2O34.204.194.154.174.174.194.224.224.214.30
Al2O3/CaO0.560.560.550.560.550.560.570.570.570.57
SiO2 + Al2O368.7068.4568.5568.8068.2069.0568.9568.9569.3069.20
R2O + RO + B2O329.9530.2030.6530.4030.4530.1529.7029.7029.9029.45
(Si + Al)/(R2O + RO + B)2.292.272.242.262.242.292.322.322.322.35
SiO2 − RO29.4528.9528.5029.0028.4529.5029.9529.9530.0030.60
Al2O3/RO0.510.500.500.500.500.510.510.510.510.51
Log3 FT, ° C.1193119811981200120112011204120412071212
Liquidus T, ° C.1129112211281129112711271127112311271122
Delta T, ° C.64767071747477818090

TABLE 8
Type 2 Glasses
Examples
Components (wt %)5354555657585960616263
SiO254.2054.5054.1255.0054.554.554.754.5054.2054.5054.80
Al2O313.3513.2513.3013.2513.2513.2513.213.2513.3513.2513.25
CaO24.5524.5524.5524.2524.5524.5524.524.5524.5524.5524.25
MgO2.552.553.002.552.672.672.552.652.852.652.55
TiO20.550.550.550.550.550.550.550.550.550.550.55
Na2O0.450.450.450.450.450.450.450.450.450.450.45
K2O0.550.550.550.550.550.550.550.550.550.550.55
Fe2O30.280.280.280.280.280.280.280.280.280.280.28
B2O33.003.003.003.003.003.003.003.003.003.003.00
F0.200.200.100.100.100.100.100.100.100.100.20
SrO0.120.120.100.120.100.100.120.120.120.120.12
RO (CaO + MgO)27.1027.1027.5526.8027.2227.2227.0527.2027.4027.2026.80
SiO2/CaO2.212.222.202.272.222.222.232.222.212.222.26
SiO2/RO2.002.011.962.052.002.002.022.001.982.002.04
SiO2/Al2O34.064.114.074.154.114.114.144.114.064.114.14
Al2O3/CaO0.540.540.540.550.540.540.540.540.540.540.55
SiO2 + Al2O367.5567.7567.4268.2567.7567.7567.9067.7567.5567.7568.05
R2O + RO + B2O331.1031.1031.5530.8031.2231.2231.0531.2031.4031.2030.80
(Si + Al)/(R2O + RO + B)2.172.182.142.222.172.172.192.172.152.172.21
SiO2 − RO27.1027.4026.5728.2027.2827.2827.6527.3026.8027.3028.00
Al2O3/RO0.490.490.480.490.490.490.490.490.490.490.49
Log3 FT, ° C.11901194119611971201119912011196119611971197
Liquidus T, ° C.11201124113211241131113711191130113011271121
Delta T, ° C.7070647370628266667076
Examples
Components (wt %)64656667686970717217374
SiO255.0554.9554.2055.2554.855.2554.9554.7554.5554.8054.70
Al2O313.2513.2513.3513.3013.2513.3013.2513.2013.4013.2013.30
CaO24.2024.324.5524.2024.2524.2024.3024.4524.4524.4024.40
MgO2.552.552.852.552.552.552.552.552.552.552.55
TiO20.550.550.550.550.550.550.550.550.550.550.55
Na2O0.450.450.450.450.450.450.450.450.450.450.45
K2O0.550.550.550.450.550.450.550.550.550.550.55
Fe2O30.280.280.280.250.280.250.280.280.280.280.28
B2O33.003.003.003.003.003.003.003.003.003.003.00
F0.100.100.100.200.100.100.100.10
SrO0.120.120.120.120.120.120.120.120.12
RO (CaO + MgO)26.7526.8527.4026.7526.8026.7526.8527.0027.0026.9526.95
SiO2/CaO2.272.262.212.282.262.282.262.242.232.252.24
SiO2/RO2.062.051.982.072.042.072.052.032.022.032.03
SiO2/Al2O34.154.154.064.154.144.154.154.154.074.154.11
Al2O3/CaO0.550.550.540.550.550.550.550.540.550.540.55
SiO2+ Al2O368.3068.2067.5568.5568.0568.5568.2067.9567.9568.0068.00
R2O + RO + B2O330.7530.8531.4030.6530.8030.6530.8531.0031.0030.9530.95
(Si + Al)/(R2O + RO + B)2.222.212.152.242.212.242.212.192.192.202.20
SiO2 − RO28.3028.1026.8028.5028.0028.5028.1027.7527.5527.8527.75
Al2O3/RO0.500.490.490.500.490.500.490.490.500.490.49
Log3 FT, ° C.11981198119912021202120312031203120312041204
Liquidus T, ° C.11271123113711261147112411251125112411211122
Delta T, ° C.7175627655797878798382

TABLE 9
Type 2 Glasses
Examples
Components (wt %)757677
SiO253.0053.0053.50
Al2O313.1013.5014.00
CaO24.0024.0024.00
MgO2.502.501.50
TiO20.500.500.50
Na2O0.900.900.90
K2O0.370.370.37
Fe2O30.100.100.10
B2O35.024.934.94
F0.500.500.50
SrO0.130.130.13
Cr2O30.130.130.13
RO (CaO + MgO)26.5026.5025.50
SiO2/CaO2.212.212.23
SiO2/RO2.002.002.10
SiO2/Al2O34.053.933.82
Al2O3/CaO0.550.560.58
SiO2 + Al2O366.1066.5067.50
R2O + RO + B2O332.7932.7031.71
(Si + Al)/(R2O + RO + B)2.022.032.13
SiO2 − RO26.5026.5028.00
Al2O3/RO0.490.510.55
Log3 FT, ° C.116711721177
Liquidus T, ° C.111011031122
Delta T, ° C.576957

TABLE 10
Type 2 Glasses
Examples
Components (wt %)787980818283848586878889
SiO255.4055.8056.2055.7556.3555.6055.8056.4056.056.0056.0056.65
Al2O313.6013.4013.6013.2013.6013.6013.6013.4013.6013.8013.6013.05
CaO24.8524.6524.0523.2523.8524.6524.4524.0524.2524.0524.2523.50
MgO2.502.502.502.552.552.502.502.502.502.502.502.55
TiO20.500.500.501.100.500.500.500.500.500.500.501.10
Na2O0.900.900.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.250.250.250.250.250.250.25
B2O32.002.002.003.002.002.002.002.002.002.002.002.00
RO27.3527.1526.5525.8026.4027.1526.9526.5526.7526.5526.7526.05
SiO2/CaO2.232.252.342.402.362.262.282.352.312.332.312.41
SiO2/RO2.032.062.122.162.132.052.072.122.092.112.092.17
SiO2/Al2O34.074.164.134.224.144.094.104.214.124.064.114.34
Al2O3/CaO0.540.540.570.570.570.550.560.550.560.570.560.56
SiO2 + Al2O369.0069.2069.8068.9569.9569.2069.4069.8069.6069.8069.6069.70
R2O + RO + B2O330.2530.0529.4529.7029.3030.0529.8529.4529.6529.4529.6528.95
(Si + Al)/2.282.302.372.322.392.302.322.372.352.372.352.41
(R2O + RO + B)
SiO2 − RO28.0528.6529.6529.9529.9528.4528.8529.8529.2529.4529.2530.60
Al2O3/RO0.500.490.510.510.510.500.500.500.510.520.510.50
Log3 FT, ° C.121712111219120412181211120912161213121912021218
Liquidus T, ° C.115311561136112711381154115611431136115111371131
Delta T, ° C.645583778057537377686587
Examples
Components (wt %)90919293949596979899
SiO256.2556.1557.7557.7556.7557.1557.2558.5557.2556.25
Al2O313.2013.0513.2012.2013.2013.0513.2012.2012.2013.20
CaO23.2523.0024.2524.2524.2524.0024.2523.4523.7523.75
MgO2.552.552.502.502.502.552.502.552.502.50
TiO21.101.101.101.101.101.101.101.101.101.10
Na2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.250.250.250.250.25
B2O33.003.001.001.001.001.001.001.002.002.00
RO25.8025.5526.7526.7526.7526.5526.7526.0026.2526.25
SiO2/CaO2.412.442.382.382.342.382.362.502.412.37
SiO2/RO2.182.202.162.162.122.152.142.252.182.14
SiO2/Al2O34.264.304.384.734.304.384.334.804.694.26
Al2O3/CaO0.560.560.540.500.540.540.540.520.510.56
SiO2 + Al2O369.4569.2070.9569.9569.9570.2070.4570.7569.4569.45
R2O + RO + B2O329.7029.4528.6528.6528.6528.4528.6527.9029.1529.15
(Si + Al)/2.342.342.672.442.442.472.472.542.382.38
(R2O + RO + B)
SiO2 − RO30.4530.6031.0031.0030.0030.6030.5032.5531 .0030.00
Al2O3/RO0.510.510.490.460.490.490.490.470.460.50
Log3 FT, ° C.1214121212401227122812351239123612271224
Liquidus T, ° C.1114117811781164116111541159115911481149
Delta T, ° C.100346263678180777975
Examples
Components (wt %)100101102103104105106107108109
SiO256.6556.7558.0555.8057.2556.7556.2556.5055.8056.75
Al2O313.0513.2012.2013.6013.2013.2013.2013.2013.8013.20
CaO23.5023.2522.9524.4522.7523.7523.7523.5024.2522.25
MgO2.552.552.552.502.502.052.552.552.502.55
TiO21.101.101.100.501.101.101.101.100.501.10
Na2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.250.250.250.250.250.250.250.250.250.25
B2O32.002.002.002.002.002.002.002.002.003.00
RO26.0525.8025.5026.9525.2525.8026.3026.0526.7524.80
SiO2/CaO2.412.442.532.282.522.392.372.402.302.55
SiO2/RO2.172.202.282.072.272.202.142.162.092.29
SiO2/Al2O34.344.304.764.104.344.304.264.284.044.30
Al2O3/CaO0.560.570.530.560.580.560.550.560.570.59
SiO2 + Al2O369.7069.9570.2569.4070.4569.9569.4569.7069.6069.95
R2O + RO + B2O328.9528.7028.4029.8528.1528.7029.2028.9529.6528.70
(Si + Al)/2.412.442.472.322.502.442.382.412.352.44
(R2O + RO + B)
SiO2 − RO30.6030.9532.5528.8532.0030.9529.9530.4529.0531.95
Al2O3/RO0.500.510.480.500.520.510.500.510.520.53
Log3 FT, ° C.1225122512251222123712301220122012221221
Liquidus T, ° C.1145114711421153114911411131113311371121
Delta T, ° C.807883698689898785100

TABLE 11
Type 2 Glasses
Examples
Components (wt %)110111112
SiO257.7557.7556.10
Al2O312.212.213.38
CaO23.7523.9524.42
MgO2.552.552.55
TiO21.101.100.55
Na2O0.900.900.90
K2O
Fe2O30.250.250.25
B2O31.401.401.30
RO (CaO + MgO)26.3026.5026.97
SiO2/CaO2.432.412.30
SiO2/RO2.202.182.08
SiO2/Al2O34.734.734.19
Al2O3/CaO0.510.510.54
SiO2 + Al2O369.9569.9569.48
R2O + RO + B2O328.6028.8029.17
(Si + Al)/(R2O + RO + B)2.442.432.38
SiO2 − RO31.4531.2529.13
Al2O3/RO0.460.460.50
Log3 FT, ° C.121712181215
Liquidus T, ° C.115111551150
Delta T, ° C.666365

TABLE 12
Type 3 Glasses
Examples
Components (wt %)113114115116117118119120121
SiO258.7057.9558.3560.0558.2558.8659.9759.1658.76
Al2O313.3513.2013.2012.9813.4013.4412.1913.2413.64
CaO23.5024.0523.6522.1423.5523.5522.2523.4523.45
MgO2.502.552.553.122.552.502.902.502.50
TiO20.501.101.100.551.100.501.500.500.50
Na2O0.3
K2O
Li2O0.900.900.900.910.900.900.900.900.90
Fe2O30.200.250.250.250.250.250.250.250.25
B2O3
RO (CaO + MgO)26.0026.6026.2025.2626.1026.0525.1525.9525.95
SiO2/CaO2.502.412.472.712.472.502.702.522.51
SiO2/RO2.262.182.232.382.232.262.382.282.26
SiO2/Al2O34.404.394.424.634.354.384.924.474.31
Al2O3/CaO0.570.550.560.590.570.570.550.560.58
SiO2 + Al2O372.0571.1571.5573.0371.6572.3072.1672.4072.40
R2O + RO + B2O327.2027.5027.1026.1727.0026.9526.0526.8526.85
(Si + Al)/(R2O + RO + B)2.652.592.642.792.652.682.772.702.70
SiO2 − RO32.7031.3532.1534.7932.1532.8134.8233.2132.81
Al2O3/RO0.510.500.500.510.510.520.480.510.53
Log3 FT, ° C.121112051211121412151216121712181218
Liquidus T, ° C.115311511146115911531153116111561150
Delta T, ° C.585465556263566268

TABLE 13
Type 3 Glasses
Examples
Components (wt %)122123124125126127128129130131
SiO258.7059.3057.6558.9658.1560.0960.2160.3359.7359.85
Al2O313.3512.1013.4013.2413.2012.2212.2412.2712.9212.95
CaO23.5022.6024.1523.6523.8523.3123.3523.4022.0022.04
MgO2.503.402.552.502.552.702.502.303.102.90
TiO20.501.501.100.501.100.500.500.501.101.10
Na2O0.600.45
Li2O0.600.450.900.900.900.900.900.900.900.90
Fe2O30.250.200.250.250.250.250.250.250.250.25
B2O3
RO (CaO + MgO)26.0026.0026.7026.1526.4026.0125.8525.7025.1024.94
SiO2/CaO2.502.622.392.492.442.582.582.582.702.72
SiO2/RO2.262.282.162.252.202.312.332.352.382.40
SiO2/Al2O34.404.904.304.454.414.924.924.924.624.62
Al2O3/CaO0.570.540.550.560.550.520.520.520.590.59
SiO2 + Al2O372.0571.4071.0572.2071.3572.3172.4572.6072.6572.80
R2O + RO + B2O327.2027.4527.6027.0527.3026.9126.7526.6026.0025.84
(Si + Al)/(R2O + RO + B)2.652.702.572.672.612.692.712.732.302.32
SiO2 − RO32.733.3030.9532.8131.7534.0834.3634.6334.6334.91
Al2O3/RO0.510.470.500.510.500.470.470.480.510.52
Log3 FT, ° C.1226120512061212123712171213121612141214
Liquidus T, ° C.1157115111541158117211631162116611641161
Delta T, ° C.69545254655451505053
Examples
Components (wt %)132133134135136137138139140141
SiO259.9760.0960.2160.0060.5759.8059.7559.6559.6059.55
Al2O312.9713.0013.0212.5013.1012.2512.2512.2512.2512.25
CaO22.0922.1322.1823.7022.3122.6022.8523.3523.6023.85
MgO2.702.502.301.901.703.102.902.502.302.10
TiO21.101.101.101.101.101.101.101.101.101.10
Na2O0.300.300.300.300.30
Li2O0.900.900.900.900.900.600.600.600.600.60
Fe2O30.250.250.250.250.25
B2O3
RO (CaO + MgO)24.7924.6324.4825.6024.0125.7025.7525.8525.9025.95
SiO2/CaO2.712.712.712.532.712.642.612.572.522.50
SiO2/RO2.422.442.462.342.522.332.322.312.302.29
SiO2/Al2O34.624.624.824.804.624.884.884.874.874.86
Al2O3/CaO0.590.590.590.530.590.540.540.520.520.51
SiO2 + Al2O372.8773.0973.2372.5073.6772.0572.0071.9071.8571.80
R2O + RO + B2O325.6925.5325.3826.5024.9126.6026.6526.7526.8026.85
(Si + Al)/(R2O + RO + B)2.332.862.892.742.962.712.702.692.682.67
SiO2 − RO35.1835.4635.7334.4036.5634.1034.0033.8033.733.60
Al2O3/RO0.470.530.530.490.550.470.480.470.470.47
Log3 FT, ° C.1219122312331239123912401236123612381234
Liquidus T, ° C.1160115511421139114111561156115911671173
Delta T, ° C.596891100989480777161
Examples
Components (wt %)142143144145146147148149150151
SiO259.5060.0059.9559.9059.8560.2160.3360.7560.2159.71
Al2O312.2512.4012.4012.4012.012.2412.2712.3513.0213.24
CaO24.1022.0523.3023.5523.8022.3422.3922.5522.5222.90
MgO1.902.302.101.901.702.502.301.702.502.50
TiO21.101.101.101.101.101.501.501.500.500.50
Na2O0.30
Li2O0.600.900.900.900.900.900.900.901.000.90
Fe2O30.250.250.260.250.250.250.250.250.25
B2O3
RO (CaO + MgO)26.0024.3525.4025.4525.5024.8424.6924.2525.0225.40
SiO2/CaO2.472.722.572.542.512.702.692.692.672.61
SiO2/RO2.292.462.362.352.352.422.442.512.412.35
SiO2/Al2O34.864.844.834.834.994.924.924.924.624.51
Al2O3/CaO0.510.560.530.530.500.550.550.550.580.58
SiO2 + Al2O371.7572.4072.3572.3071.8572.4572.6073.1073.2372.95
R2O + RO + B2O326.9025.2326.3026.3526.4025.7425.5925.1526.0226.30
(Si + Al)/(R2O + RO + B)2.672.872.752.742.722.812.832.912.812.77
SiO2 − RO33.5035.6536.5534.4534.3535.3735.6436.5035.1934.31
Al2O3/RO0.470.510.530.490.470.490.500.500.520.52
Log3 FT, ° C.1234123012311224122412151231124012311227
Liquidus T, ° C.1181114611521156115611621160116611431142
Delta T, ° C.53847968685371748885
Examples
Components (wt %)152153154155156157158159160161162
SiO259.4660.0260.2660.1460.1060.2360.1060.2360.1460.0560.05
Al2O313.2412.3512.4012.3713.0012.2513.0012.2512.3712.9812.98
CaO23.1523.3523.4523.4022.1523.3622.1523.3623.4022.1422.14
MgO2.502.542.552.542.502.502.502.502.543.123.12
TiO20.500.500.510.511.100.511.100.510.510.550.55
Na2O
Li2O0.901.000.600.800.900.900.900.900.800.910.91
Fe2O30.250.230.230.230.250.250.250.250.230.250.25
B2O3
RO (CaO + MgO)26.6525.8926.0025.9424.6525.8624.6525.8625.9425.2625.26
SiO2/CaO2.572.572.572.572.712.582.712.582.572.712.71
SiO2/RO2.322.322.322.322.442.332.442.332.322.382.38
SiO2/Al2O34.494.864.894.864.624.924.624.924.864.634.63
Al2O3/CaO0.570.530.530.530.590.520.590.520.530.590.59
SiO2 + Al2O372.7072.3772.6672.5173.1072.4873.1072.4872.5173.0373.03
R2O + RO + B2O326.5026.8526.6026.7425.5526.7625.5526.7626.7426.1726.17
(Si + Al)/(R2O + RO + B)2.742.702.732.712.862.712.862.712.712.792.79
SiO2 − RO33.8134.1334.2634.2034.4534.3735.4534.4434.2034.7934.79
Al2O3/RO0.520.480.480.480.530.470.530.470.480.510.51
Log3 FT, ° C.12261209123012191235122012371224121912191223
Liquidus T, ° C.11471159115811591133116011361158115911641163
Delta T, ° C.795072601026010166605560

TABLE 14
Type 4 Glasses
Examples
Components (wt %)163164165166167168169
SiO258.3058.2058.1058.1558.1558.0058.25
Al2O313.0313.0313.0313.2013.3313.0313.33
CaO23.5423.6423.7422.8523.3923.8423.29
MgO2.502.502.502.552.502.502.50
TiO20.500.500.501.100.500.500.50
Li2O0.900.900.900.900.900.900.90
ZnO1.001.001.001.001.001.001.00
Fe2O30.230.230.230.250.230.230.23
B2O3
RO (CaO + MgO)26.0426.1426.2425.4025.8926.3425.79
SiO2/CaO2.482.462.452.542.492.432.50
SiO2/RO2.242.232.212.292.252.202.26
SiO2/Al2O34.474.474.464.414.364.454.37
Al2O3/CaO0.550.550.550.580.570.550.57
SiO2 + Al2O371.3371.2371.1371.3571.4871.0371.58
R2O + RO + B2O326.9427.0427.1426.3026.7927.2426.69
(Si + Al)/(R2O + RO + B)2.652.632.622.712.672.612.68
SiO2 − RO32.2632.0631.8632.7532.2631.6632.46
Al2O3/RO0.500.500.500.520.510.490.52
Log3 FT, ° C.1204120512061207120812081213
Liquidus T, ° C.1147114811441136115211521146
Delta T, ° C.57576271565667

TABLE 15
Type 4 Glasses
Examples
Components (wt %)170171172173174175
SiO258.0058.1057.3557.9559.6159.47
Al2O313.0313.6313.2013.2012.1612.16
CaO23.8423.1423.6524.0523.5024.22
MgO2.502.502.552.552.501.90
TiO20.500.501.101.101.101.10
Li2O0.900.900.900.900.450.45
ZnO1.001.001.001.000.450.45
Fe2O30.230.230.250.25
B2O3
RO (CaO + MgO)26.3425.6426.2026.6026.0026.12
SiO2/CaO2.432.512.422.412.542.46
SiO2/RO2.202.262.192.182.292.28
SiO2/Al2O34.454.264.344.394.904.89
Al2O3/CaO0.550.590.560.550.520.50
SiO2 + Al2O371.0371.7370.5571.1571.7771.63
R2O + RO + B2O327.2426.5427.1027.5026.4526.57
(Si + Al)/(R2O + RO + B)2.612.702.602.602.712.70
SiO2 − RO31.6632.4631.1531.3033.6133.35
Al2O3/RO0.490.530.500.500.470.47
Log3 FT, ° C.120812121195119512291218
Liquidus T, ° C.114911571141114011541159
Delta T, ° C.595554557559

TABLE 16
Type 5 Glasses
Example
Components (wt %)176177
SiO259.0058.70
Al2O312.0011.90
CaO22.5022.4
MgO3.403.40
TiO21.001.00
Na2O0.900.90
ZnO1.001.50
K2O
Fe2O30.200.20
B2O3
RO25.9025.80
SiO2/CaO2.622.62
SiO2/RO2.282.28
SiO2/Al2O34.924.93
Al2O3/CaO0.530.53
SiO2 + Al2O371.0070.60
R2O + RO + B2O326.8026.70
(Si + Al)/(R2O + RO + B)2.652.64
SiO2 − RO33.1032.90
Al2O3/RO0.460.46
Log3 FT ° C.12341231
Liquidus T ° C.11751181
Delta(T3-TL) ° C.5950

TABLE 17
Type 6 Glasses
Examples
Components (wt %)178179180181182183184185186187
SiO258.0058.1058.3057.9058.1157.6058.5057.8058.0057.80
Al2O313.0313.0313.0313.2313.3613.2312.7613.4313.0313.03
CaO23.8423.7423.5423.7423.4023.8423.6123.6423.8423.84
MgO2.502.502.502.502.502.502.502.502.502.50
TiO20.500.500.500.500.500.500.500.500.500.50
Na2O0.10
K2O
Li2O0.900.900.900.900.900.800.900.900.900.90
Fe2O30.230.230.230.230.230.230.230.230.230.23
B2O31.001.001.001.001.001.201.001.001.001.20
RO (CaO + MgO)26.3426.2426.0426.2425.9026.3426.1126.1426.3426.34
SiO2/CaO2.432.452.482.442.482.422.482.452.432.42
SiO2/RO2.202.212.242.212.242.192.242.212.202.19
SiO2/Al2O34.454.464.474.384.354.354.584.304.454.44
Al2O3/CaO0.550.550.550.560.570.550.540.570.550.55
SiO2 + Al2O371.0371.1371.3371.1371.4770.8371.2671.2371.0370.83
R2O + RO + B2O328.2428.1427.9428.1427.8028.4428.0128.0428.2428.44
(Si + Al)/(R2O + RO + B)2.522.532.552.532.572.492.542.542.522.49
SiO2 − RO31.6631.8632.2631.6632.2131.2632.3931.6631.6631.46
Al2O3/RO0.490.500.500.500.520.500.490.510.490.49
Log3 FT, ° C.1192119411951195119611961197119711981198
Liquidus T, ° C.1137113511401137113311331139113911381135
Delta T, ° C.55595558636358586063

TABLE 18
Type 6 Glasses
Examples
Components (wt %)188189190191192193194195196*197*
SiO258.0057.9058.1558.2558.0058.1058.3058.2058.7458.64
Al2O313.4313.4313.3313.3313.6313.6313.0313.0313.0513.15
CaO23.4423.5423.3923.2923.2423.1423.5423.6422.9722.97
MgO2.502.502.502.502.502.502.502.502.362.36
TiO20.500.500.500.500.500.500.500.500.490.49
Na2O
K2O0.090.09
Li2O0.900.900.900.900.900.900.900.900.910.91
Fe2O30.230.230.230.230.230.230.230.230.290.29
B2O31.001.001.001.001.001.001.001.001.001.00
RO (CaO + MgO)25.9426.0425.8925.7925.7425.6426.0426.1425.3325.33
SiO2/CaO2.472.452.492.512.502.512.482.462.562.55
SiO2/RO2.242.222.252.262.252.272.242.232.322.32
SiO2/Al2O34.324.314.364.374.264.264.474.474.504.46
Al2O3/CaO0.570.570.570.570.590.590.550.550.570.57
SiO2 + Al2O371.4371.3371.4871.5871.6371.7371.3371.2371.7971.79
R2O + RO + B2O327.8427.9427.7927.6927.1427.5427.9428.0427.3327.33
(Si + Al)/(R2O + RO + B)2.572.552.572.592.642.602.552.542.632.63
SiO2 − RO32.0631.8632.2632.4632.2632.4632.2632.0633.4133.31
Al2O3/RO0.510.520.510.520.530.530.500.500.520.52
Log3 FT, ° C.1202120312031202120712121200120112101209
Liquidus T, ° C.1139113711361145114411461132113711451151
Delta T, ° C.63666757636668646558
Examples
Components (wt %)198*199200201202203204205206207
SiO258.6458.7557.8057.6057.6057.6058.5058.4058.3058.40
Al2O312.9512.9313.2313.2313.2313.0312.7612.7613.0313.03
CaO22.8722.9323.8423.8423.8424.0423.6123.7123.5423.44
MgO2.362.362.502.502.502.502.502.502.502.50
TiO20.490.500.500.500.500.500.500.500.500.50
Na2O0.040.200.20
K2O0.090.10
Li2O0.910.900.900.900.700.700.900.900.900.90
Fe2O30.290.290.230.230.230.230.230.230.230.23
B2O31.001.201.001.201.201.201.001.001.001.00
RO (CaO + MgO)25.2325.2926.3426.3426.3426.5426.1126.2126.0425.94
SiO2/CaO2.562.562.422.422.422.402.482.462.482.49
SiO2/RO2.322.322.192.192.192.172.242.232.242.25
SiO2/Al2O34.534.544.374.354.354.374.584.584.474.48
Al2O3/CaO0.570.560.550.550.550.540.540.540.550.56
SiO2 + Al2O371.5971.6871.0370.8370.8370.6371.2671.1671.3371.43
R2O + RO + B2O327.2327.5328.2428.4428.4428.6428.0128.1127.9427.84
(Si + Al)/(R2O + RO + B)2.632.602.512.492.492.472.542.532.552.57
SiO2 − RO33.4133.4631.4631.2631.2631.0632.3932.1932.2632.36
Al2O3/RO0.510.510.500.500.500.490.490.490.500.51
Log3 FT, ° C.1204121012011200120812011202120312011208
Liquidus T, ° C.1142112711261125113511451141114511381137
Delta T, ° C.62837575735661586371
Examples
Components (wt %)208209210211212213214215216217
SiO258.1558.2558.7058.0057.6058.6158.6158.0058.4058.40
Al2O313.3313.3312.7513.0313.0312.1612.1613.2313.3613.03
CaO23.3923.2923.5023.8424.0423.5023.5023.6423.1123.44
MgO2.502.502.502.502.502.502.502.502.502.50
TiO20.500.500.500.500.501.101.100.500.500.50
Na2O0.600.45
K2O
Li2O0.900.900.600.900.900.900.450.900.900.90
Fe2O30.250.250.250.230.230.230.230.230.230.23
B2O31.001.000.601.001.201.001.001.001.001.00
RO (CaO + MgO)25.8925.7926.0026.3426.5426.0026.0026.1425.6125.94
SiO2/CaO2.492.502.502.432.402.492.492.452.522.49
SiO2/RO2.252.262.262.202.172.252.252.222.282.25
SiO2/Al2O34.364.374.604.454.424.824.824.384.374.48
Al2O3/CaO0.570.570.540.550.540.520.520.560.580.56
SiO2+ Al2O371.4871.5871.4571.0370.6370.7770.7771.2371.7671.43
R2O + RO + B2O327.7927.6927.8028.2428.6427.9027.9028.0427.5127.84
(Si + Al)/(R2O + RO + B)2.572.592.572.522.472.542.542.542.612.57
SiO2 − RO32.2632.4632.7031.6631.0632.6132.6131.8632.7932.46
Al2O3/RO0.510.520.490.490.490.470.470.510.520.50
Log3 FT, ° C.1197120012161202119412011227120112041201
Liquidus T, ° C.1130113411601137114211421159113511331136
Delta T, ° C.67665665525968667165
Examples
Components (wt %)218219220221222223224225226227
SiO258.5058.6058.0058.1058.1058.7058.7058.7058.6158.40
Al2O313.0313.0313.6313.2313.4312.7512.3512.3512.1612.76
CaO23.3423.2423.2423.5423.3423.5023.5023.5023.5023.71
MgO2.502.502.502.502.502.502.502.502.502.50
TiO20.500.500.500.500.500.500.500.501.100.50
Na2O0.300.600.30
K2O
Li2O0.900.900.900.900.900.900.600.900.900.90
Fe2O30.230.230.230.230.230.250.250.250.230.23
B2O31.001.001.001.001.000.601.001.001.001.00
RO (CaO + MgO)25.8425.7425.7426.0425.8426.0026.0026.0026.0026.21
SiO2/CaO2.512.512.502.472.492.502.502.502.492.46
SiO2/RO2.262.282.252.232.252.262.262.262.252.23
SiO2/Al2O34.494.504.264.394.334.604.754.754.824.58
Al2O3/CaO0.560.560.590.560.580.540.530.530.520.54
SiO2 + Al2O371.5371.6371.6371.3371.5371.4571.0571.0570.7771.16
R2O + RO + B2O327.7427.6427.6427.9427.7427.8028.2028.2027.9028.11
(Si + Al)/(R2O + RO + B)2.582.592.592.552.582.572.522.522.542.53
SiO2 − RO32.6632.8632.2632.0632.2632.7032.7032.7032.6132.19
Al2O3/RO0.500.510.530.510.520.490.480.480.470.49
Log3 FT, ° C.1204120412061199120412041207120211941194
Liquidus T, ° C.1133113511361133113411531157114911411144
Delta T, ° C.71697063705150535350
Examples
Components (wt %)228229230231232233234235236237
SiO258.8057.6058.1158.9158.1158.3058.2058.1058.7058.70
Al2O312.4613.0313.3612.1613.3613.0313.0313.0313.3513.35
CaO23.6124.0423.4023.8023.4023.5423.6423.7423.5023.50
MgO2.502.502.502.502.502.502.502.502.502.50
TiO20.500.500.500.500.500.500.500.500.500.50
Na2O0.10
K2O
Li2O0.900.800.900.900.900.900.900.900.900.60
Fe2O30.230.230.230.230.230.230.230.230.250.25
B2O31.001.201.001.001.001.001.001.000.300.60
RO (CaO + MgO)26.1126.5425.9026.3025.9026.0426.1426.2426.0026.00
SiO2/CaO2.492.402.482.482.482.482.462.452.502.50
SiO2/RO2.252.172.242.242.242.242.232.212.262.26
SiO2/Al2O34.704.424.354.844.354.474.474.464.404.40
Al2O3/CaO0.530.540.570.510.570.550.550.550.570.57
SiO2 + Al2O371.2670.6371.4771.0771.4771.2371.2371.1372.0572.05
R2O + RO + B2O328.0128.6427.8028.2027.8027.9428.0428.1427.2027.20
(Si + Al)/(R2O + RO + B)2.542.472.572.522.572.552.542.532.652.65
SiO2 − RO32.6931.0632.2132.6132.2132.2632.0631.8632.7032.70
Al2O3/RO0.480.490.520.460.520.500.500.500.510.51
Log3 FT, ° C.1195119612291216121312021202120512071224
Liquidus T, ° C.1145114511551148114211361136113711441145
Delta T, ° C.5051133123126120119122114142
Examples
Components (wt %)238239240241242243244245246247
SiO258.1158.2059.5359.6159.1159.1159.1659.2159.1159.36
Al2O313.3613.2312.2512.1612.1612.1612.1612.1612.1612.41
CaO23.4023.4423.1723.5023.0023.0023.2023.4023.5023.60
MgO2.502.502.522.502.502.502.252.002.002.00
TiO20.500.500.501.101.101.101.101.101.100.50
Na2O
K2O
Li2O0.900.900.800.450.900.900.900.900.900.90
Fe2O30.230.230.230.230.230.230.230.230.230.23
B2O31.001.001.000.451.001.001.001.001.001.00
RO (CaO + MgO)25.9025.9425.6926.0025.5025.5025.4525.4025.5025.60
SiO2/CaO2.482.482.572.542.572.572.552.532.512.51
SiO2/RO2.242.242.322.292.322.322.322.332.322.32
SiO2/Al2O34.354.404.864.904.864.864.874.874.874.78
Al2O3/CaO0.570.560.530.520.530.530.520.520.520.53
SiO2 + Al2O371.4771.4371.7871.7771.2771.2771.3271.3771.2771.77
R2O + RO + B2O327.8027.8427.4926.9027.4027.4027.3527.3027.4027.50
(Si + Al)/(R2O + RO + B)2.572.572.612.672.602.602.612.612.602.61
SiO2 − RO32.2132.2633.8433.6133.6133.6133.7133.8133.6133.76
Al2O3/RO0.520.510.480.470.480.480.480.480.480.53
Log3 FT, ° C.1212120412141230120512161218121312091216
Liquidus T, ° C.1135113511431155114211431147115311531153
Delta T, ° C.1391247175637371605663
Examples
Component (wt %)248249250251252253254255256257
SiO259.3159.3659.4159.1159.1659.2159.1659.1159.0159.21
Al2O312.5612.5112.4612.1612.1612.1612.2612.2612.3612.16
CaO23.5023.5023.5023.0023.2023.4023.4523.5023.5023.50
MgO2.002.002.002.502.252.002.502.502.502.50
TiO20.500.500.501.101.101.100.500.500.500.50
Na2O
K2O
Li2O0.900.900.900.900.900.900.900.900.900.90
Fe2O30.230.230.230.230.230.230.230.230.230.23
B2O31.001.001.001.001.001.001.001.001.001.00
RO (CaO + MgO)25.5025.5025.5025.5025.4525.4025.9526.0026.0026.00
SiO2/CaO2.522.532.532.572.552.532.522.522.512.52
SiO2/RO2.332.332.332.322.322.332.282.272.272.28
SiO2/Al2O34.724.754.774.864.874.874.834.824.774.87
Al2O3/CaO0.530.530.530.530.520.520.520.520.530.52
SiO2 + Al2O371.8771.8771.8771.2771.3271.3771.4271.3771.3771.37
R2O + RO + B2O327.4027.4027.4027.4027.3527.3027.8527.9027.9027.90
(Si + Al)/(R2O + RO + B)2.622.622.622.602.612.612.562.562.562.56
SiO2 − RO33.8133.8633.9133.6133.7133.8133.2133.1133.0133.21
Al2O3/RO0.490.490.490.480.480.480.470.470.480.47
Log3 FT, ° C.1220122012201216121412201209121012101201
Liquidus T, ° C.1153115811551144114711581150115211521143
Delta T, ° C.67626572676259585858
Examples
Components (wt %)258259260261262263264265266267
SiO258.7558.7558.1058.7059.1159.3159.2154.6056.7557.85
Al2O312.9312.9313.6313.3512.1612.2612.2613.3513.2012.45
CaO22.9322.9323.1423.5023.5022.3023.4024.5523.9524.05
MgO2.362.362.502.502.002.502.502.552.552.55
TiO20.500.500.500.501.100.500.500.351.100.55
Na2O0.140.240.150.600.60
K2O0.100.100.55
Li2O0.800.700.900.300.900.900.900.300.300.30
Fe2O30.290.290.230.250.230.230.230.280.250.35
B2O31.201.201.000.901.001.001.003.001.401.30
F0.20
SrO0.12
RO (CaO + MgO)25.2925.2925.6426.0025.5024.8025.9027.1026.5026.60
SiO2/CaO2.562.562.512.502.522.662.532.222.372.39
SiO2/RO2.322.322.272.262.322.392.292.012.142.35
SiO2/Al2O34.544.544.264.404.864.844.834.094.304.65
Al2O3/CaO0.560.560.590.570.520.550.520.540.550.52
SiO2 + Al2O371.6871.6871.7372.0571.2771.5771.4767.9569.9571.30
R2O + RO + B2O327.5327.5327.5427.2027.4026.7027.8031.1028.8028.80
(Si + Al)/(R2O + RO + B)2.602.602.602.652.602.682.572.182.432.48
SiO2 − RO33.4633.4632.4632.7033.6134.5133.3127.5030.2531.25
Al2O3/RO0.510.510.530.510.480.490.470.490.500.47
Log3 FT, ° C.1211121812041239121512091210118712061208
Liquidus T, ° C.1127112911151143115511481156113311521154
Delta T, ° C.84898996606154545454

*compositions include 0.05 wt % SrO and 0.08 wt % SO3

TABLE 19
Misc. Glasses
Examples
Components (wt %)268269270271272
SiO257.8258.7058.7057.7258.61
Al2O311.8013.3513.3511.8012.16
CaO22.8023.5023.5022.8023.50
MgO2.432.502.502.522.50
TiO21.070.500.501.071.10
Na2O0.870.900.87
Li2O0.300.300.30
ZnO0.30
MnO3.000.30
MnO23.00
Fe2O30.220.250.250.220.23
B2O30.901.00
RO25.2326.0026.0025.3226.00
SiO2/CaO2.542.502.502.532.49
SiO2/RO2.292.262.262.282.25
SiO2/Al2O34.904.404.404.894.82
Al2O3/CaO0.520.570.570.520.52
SiO2 + Al2O369.6272.0572.0569.5270.77
RO2 + RO + B2O326.1027.2026.3026.1927.30
(Si + Al)/2.672.652.742.652.59
(R2O + RO + B)
SiO2 − RO32.5932.7032.7032.4032.61
Al2O3/RO0.470.510.510.470.47
Log3 FT, ° C.12191239124112221223
Liquidus T, ° C.11631143116511611139
Delta T, ° C.5296766194

TABLE 20
Production Glasses
Examples
Components (wt %)273274275276277278279
SiO257.0757.2156.9456.6856.7156.5355.97
Al2O312.6912.7712.7212.6812.9512.8412.68
CaO23.9124.1524.0024.1124.5624.4224.00
MgO2.532.572.562.582.442.422.45
TiO21.091.121.121.091.071.071.05
Na2O0.890.900.870.900.920.920.88
K2O0.0600.0500.0500.0600.0700.0600.060
Fe2O30.2550.2710.2550.2630.2780.2670.265
B2O31.371.361.421.401.541.701.36
SO30.0290.0320.0320.0310.0280.0240.025
SrO0.0400.0400.0500.0500.0500.0500.050
Cr2O30.0020.0020.0020.0020.0090.0080.007
RO26.4426.7226.5626.6927.0026.8426.45
SiO2/CaO2.392.372.372.352.312.312.33
SiO2/RO2.162.142.142.122.102.112.12
SiO2/Al2O34.504.484.484.474.384.404.41
Al2O3/CaO0.530.530.530.530.530.530.53
SiO2 + Al2O369.7669.9869.6669.3669.6669.3768.65
RO2 + RO + B2O328.9629.2529.1129.2529.7429.7328.96
(Si + Al)/(R2O + RO + B)2.412.392.392.372.342.332.37
SiO2 − RO30.6330.4930.3829.9929.7129.6929.52
Al2O3/RO0.480.480.480.480.480.480.48
Log3 FT, ° C.12141217120312121212
Liquidus T, ° C.11471134114511471134
Delta T, ° C.6783586576
Examples
Components (wt %)280281282283284285
SiO256.7056.6656.6356.5456.4356.61
Al2O312.9112.8612.8512.7912.7512.83
CaO24.6124.5324.6924.5324.4425.24
MgO2.542.562.602.542.542.55
TiO21.101.090.940.941.091.20
Na2O0.910.900.930.900.900.92
K2O0.0600.0600.0700.0700.0500.050
Fe2O30.2600.2650.2670.2680.2700.279
B2O31.321.151.341.271.241.29
SO30.0180.0200.0180.0160.0140.016
SrO0.0400.0400.0400.0400.0400.040
Cr2O30.0040.0040.0030.0020.0080.004
RO27.1527.0927.2927.0726.9827.79
SiO2/CaO2.302.312.292.302.312.24
SiO2/RO2.092.092.082.092.092.04
SiO2/Al2O34.394.414.414.424.434.41
Al2O3/CaO0.520.520.520.520.520.51
SiO2 + Al2O369.6169.5269.4869.3369.1869.44
RO2 + RO + B2O329.6429.4129.8329.5129.3930.28
(Si + Al)/(R2O + RO + B)2.352.362.332.352.352.29
SiO2 − RO29.5529.5729.3429.4729.4528.82
Al2O3/RO0.480.470.470.470.470.46
Log3 FT, ° C.12131214
Liquidus T, ° C.11491158
Delta T, ° C.6455

TABLE 21
Summary Sheet
Type 1Type 2Type 3Type 4Type 5
GlassesGlassesGlassesGlassesGlassesType 6 Glasses
LowHighLowHighLowHighLowHighLowHighLowHigh
RO (CaO + MgO)26.3027.0524.8027.5624.0126.7025.4026.6025.8025.9025.2926.60
SiO2/CaO2.352.472.202.552.392.712.412.542.622.622.222.66
SiO2/RO2.132.231.962.292.162.522.182.292.282.282.012.39
SiO2/Al2O34.254.843.794.764.304.994.264.904.924.934.094.90
Al2O3/CaO0.510.580.510.590.500.590.500.590.530.530.510.59
SiO2 + Al2O370.8571.8666.1070.9571.0573.6771.0371.7370.6071.0067.9572.05
R2O + RO + B2O327.2027.9528.1532.7925.1527.6026.3027.5026.7026.8026.7031.10
(Si + Al)/(R2O + RO + B)2.552.642.022.672.302.962.602.712.642.652.182.68
SiO2 − RO30.5532.5526.5032.5530.9536.5631.1533.6132.9033.1027.5033.91
Al2O3/RO0.460.520.460.560.470.530.470.530.460.460.460.53

TABLE 22
Summary Sheet
Types 2 &Production
Types1&,6 GlassesGlasses
Types 1 &Types 3-63-5, Glasses(contains(contains
2 GlassesGlasses(boron-free)boron)boron)
LowHighLowHighLowHighLowHighLowHigh
RO (CaO + MgO)24.8027.5624.0126.7024.0126.9024.8027.5626.4427.79
SiO2/CaO2.202.552.392.712.362.732.202.662.242.37
SiO2/RO1.962.292.162.522.142.521.962.392.082.16
SiO2/Al2O33.794.844.264.994.264.993.794.904.384.50
Al2O3/CaO0.510.590.500.590.500.590.510.590.510.53
SiO2 + Al2O366.1071.4570.6073.6770.8573.6766.1072.0568.6569.98
R2O + RO + B2O327.2032.7925.1528.6425.1527.8026.9032.7928.9630.28
(Si + Al)/(R2O + RO + B)2.022.672.302.962.302.962.022.682.292.41
SiO2 − RO26.5032.5530.9536.5630.5536.5626.5033.9128.8230.63
Al2O3/RO0.460.560.460.530.460.530.460.560.460.48