Title:
NON-SLIP ARTICLE OF MANUFACTURE AND PROCESS FOR MAKING SAME
United States Patent 3802951
Abstract:
Forming an uncured rubber-like matrix, adapted to be aeration cured, and having a pluralith of aluminum pieces and disconnected fiber material pieces irregularly positioned therein, and hermetically sealing that matrix mixture in a can for later formation of a non-slip flexible article in adhesive adherence to the surface to which applied and the bonding of the aluminum pieces therein, the adhesive and flexible characteristic of the matrix being assisted by the fiber material pieces.
US Patent References:
Vulcanized sole
Brown - September 1922 - 1428356
Tread for boots or shoes
Mason - September 1924 - 1507844
Manufacture of cork-rubber composition for shoe soles, etc.
Cutler - July 1926 - 1591018
Tread material and method of making the same
Grosjean - October 1928 - 1687441
Embedding of abrasive and like particles in rubber
Stahl - June 1937 - 2084784
Vulcanized sole
Brown - September 1922 - 1428356
Tread for boots or shoes
Mason - September 1924 - 1507844
Manufacture of cork-rubber composition for shoe soles, etc.
Cutler - July 1926 - 1591018
Tread material and method of making the same
Grosjean - October 1928 - 1687441
Embedding of abrasive and like particles in rubber
Stahl - June 1937 - 2084784
Application Number:
05/202387
Publication Date:
04/09/1974
Filing Date:
11/26/1971
View Patent Images:
Export Citation:
Primary Class:
Other Classes:
428/338, 524/514, 524/521, 524/41, 36/32R, 428/492, 524/513, 428/457, 523/220, 524/9, 524/34, 428/361, 36/59R, 524/441, 524/925
International Classes:
A43B13/22; A43B13/14; B32B5/16
Field of Search:
161/162,168 260/41.5R 36/32R,32A,59R,59A,59B,59C,59D 106/38 252/305
US Patent References:
| 2336388 | Bonding rubber to aluminum | December 1943 | Beebe | |
| 2764454 | Aerosol apparatus for decorative coating and process for making said apparatus | September 1956 | Edelstein | |
| 2766157 | Method of protecting and connecting mating electrical conductor members | October 1956 | Peterson | |
| 2986198 | Surface covering and process therefor | May 1961 | Kolker et al. | |
| 3361679 | Aerosolized halogenated olefin polymer composition | January 1968 | Paulus | |
| 3475205 | METHOD AND COMPOSITION FOR REDUCING SLIPPAGE AND SKIDDING OF RUBBER SURFACES ON ICE | October 1969 | Byers | |
| 3629051 | NONSLIP ARTICLE OF MANUFACTURE AND PROCESS FOR MAKING SAME | December 1971 | Mitchell |
Primary Examiner:
Lesmes, George F.
Assistant Examiner:
Thibodeau, Paul J.
Parent Case Data:
This invention is a continuation in part of my copending application, Ser. No. 829,869, filed June 3, 1969, issued as Pat. No. 3,629,051, which in turn was a continuation in part of then co-pending Ser. No. 730,181, filed May 17, 1968, entitled Non-Slip Article of Manufacture and Process for Making Same, now U.S. Pat. No. 3,573,155, and so is also a continuation in part of applicant's said prior application, Ser. No. 730,181, filed May 17, 1968, entitled Non-slip Article of Manufacture, now issued as U.S. Pat. No. 3,573,155.
Claims:
1. A dough-rubber-like uncured matrix, adapted to be hermatically air-sealed in a can and to be aeration cured as a flexible non-slip sole product on can opening, and having, in combination therewith, a myriad of aluminum pieces each of a dimension of less than 3 inches in one direction and a thickness from one two hundred fifty-sixths of an inch to three-eighths of an inch, and of disconnected fiber material pieces of the class of polyamide, polyester, acrylic or cellulose acetate interspersed therein, whereby said fiber material pieces assist the matrix, or opening of the can and aeration curing of the matrix into a rubber-like sole product of from 20 to 80 durometer hardness, in enhancing the strength, flexibility and adhesive qualities of the matrix and also assist in effecting a bonding of the aluminum pieces in and as a part of the matrix
2. A dough-rubber-like canned matrix combination as defined in preceding claim 1 and characterized further by the matrix being of a synthetic rubber, and the fiber material pieces being of one or the other of said synthetic fiber material, and with the aluminum pieces being from 20 to 60
3. A non-slip foot wear 20 to 80 durometer rubber-like product comprising in combination, a flexible cured rubber-like matrix having a plurality of bendable aluminum pieces bonded therein and a plurality of disconnected pieces of fiber material of either polyamide, polyester, acrylic, cellulose acetate, hemp or cotton all being irregularly interspersed and bonded therein, with said fiber material pieces assisting in the bonding
4. The method of forming a flexible non-slip foot wear article, which comprises the use of an elastomeric uncured rubber-like matrix adapted to be aeration cured to 20 to 80 durometer and having a plurality therein of less than 60 percent by volume of individual aluminum pieces each of a length of less than 3 inches and of a thickness varying from one two hundred fifty-sixths of an inch to three-eighths of an inch and the matrix also having a plurality of disconnected irregularly interspersed individual facric material pieces therein of either polyamide, polyester, acrylic, cellulose acetate, hemp or cotton and each less than three inches long and with said fabric pieces being less than 50 percent by volume of the matrix and which includes the steps of:
5. In a non-slip rubber-like 20 to 80 durometer foot wear product, in combination, a rubber-like matrix and a plurality of bendable irregular shaped aluminum pieces bonded therein, each of said aluminum pieces being of a dimension of less than 3 inches in one direction and of a thickness greater than one two hundred fifty-sixths of an inch and said aluminum pieces being from 20 to 60 percent by volume of the total mass product.
6. In a non-slip rubberlike 20 to 80 durometer foot wear product, in combination, a rubber-like matrix and a plurality of die-stamped irregular and different size and shape rigid aluminum pieces bonded therein, each of said aluminum pieces being of a dimension of upwards of 11/2 inches in any one direction and of a thickness from one two hundred fifty-sixths of an inch to three-eighths of an inch, and said aluminum pieces being from 20 to 60 percent by volume of the total mass product.
2. A dough-rubber-like canned matrix combination as defined in preceding claim 1 and characterized further by the matrix being of a synthetic rubber, and the fiber material pieces being of one or the other of said synthetic fiber material, and with the aluminum pieces being from 20 to 60
3. A non-slip foot wear 20 to 80 durometer rubber-like product comprising in combination, a flexible cured rubber-like matrix having a plurality of bendable aluminum pieces bonded therein and a plurality of disconnected pieces of fiber material of either polyamide, polyester, acrylic, cellulose acetate, hemp or cotton all being irregularly interspersed and bonded therein, with said fiber material pieces assisting in the bonding
4. The method of forming a flexible non-slip foot wear article, which comprises the use of an elastomeric uncured rubber-like matrix adapted to be aeration cured to 20 to 80 durometer and having a plurality therein of less than 60 percent by volume of individual aluminum pieces each of a length of less than 3 inches and of a thickness varying from one two hundred fifty-sixths of an inch to three-eighths of an inch and the matrix also having a plurality of disconnected irregularly interspersed individual facric material pieces therein of either polyamide, polyester, acrylic, cellulose acetate, hemp or cotton and each less than three inches long and with said fabric pieces being less than 50 percent by volume of the matrix and which includes the steps of:
5. In a non-slip rubber-like 20 to 80 durometer foot wear product, in combination, a rubber-like matrix and a plurality of bendable irregular shaped aluminum pieces bonded therein, each of said aluminum pieces being of a dimension of less than 3 inches in one direction and of a thickness greater than one two hundred fifty-sixths of an inch and said aluminum pieces being from 20 to 60 percent by volume of the total mass product.
6. In a non-slip rubberlike 20 to 80 durometer foot wear product, in combination, a rubber-like matrix and a plurality of die-stamped irregular and different size and shape rigid aluminum pieces bonded therein, each of said aluminum pieces being of a dimension of upwards of 11/2 inches in any one direction and of a thickness from one two hundred fifty-sixths of an inch to three-eighths of an inch, and said aluminum pieces being from 20 to 60 percent by volume of the total mass product.
Description:
This invention relates to non-slip surfaces, and particularly to non-slip surfaces of an elastomeric character having aluminum gripping or non-slip particles embedded into the elastomer. While my invention may be used for other types of non-slip surfaces, it will be hereinafter described in connection with a preferred use, that is, for Fishermen's footwear.
The portion of the term of the patent, to be granted on this application, subsequent to Mar. 30, 1988, is, therefore, hereby disclaimed.
Fishermen encounter severe problems in stream fishing particularly, when their boots or shoes become wet in wading the stream, of slipping on wet rocks, which, late in the summer, have a slime, moss or algae thereon.
It has been discovered that aluminum has an inherent characteristic of being non-slip when wet. Aluminum plates have been at times clamped onto the sole of a boot, but they have been found to be cumbersome and difficult to hold onto the soles.
Applicant has heretofore perfected the use of a myriad of irregular waste aluminum particle shavings or mill-cutting chips interspersed in a quantity of elastomer or matrix, and wherein the aluminum chips are adhesively and/or mechanically bonded and held in place therein. Applicant has provided an elastomer on aeration to cure or finish into a resilient elastomeric state.
Pieces of aluminum larger than mill-cuttings have not heretofore been successfully bonded to that type of an elastomer, as they have become loose and thus were lost on flexing of the elastomer.
Applicant has now perfected and used pieces of aluminum larger than mill cuttings, including regular shaped pieces, in bonding them successfully into that type of a matrix by the addition of disconnected pieces of a synthetic fabric material as part of the filler of his elastomeric matrix, in combination with such larger pieces. Throughout this application Applicant will generally refer to such fabric material by their trade names, for convenience. He has discovered that the addition, for example, of pieces of nylon fabric material in his matrix, in combination with such aluminum pieces therein, causes a definite bonding of those larger aluminum pieces in and to his matrix.
This invention comprises, in essence, the combination of an elastomeric matrix material of natural or artificial rubber, such as of a neoprene liquid solution capable of self-curing on exposure to the atmosphere, having a quantity of various sizes or dimensions of aluminum particles or pieces interspersed therein and having a quantity of disconnected synthetic fabric pieces also interspersed therein. The quantity and proportion of the aluminum pieces can vary from approximately 20 to 60 percent by volume of the total resultant mass, and with the quantity of such synthetic as nylon pieces therein also varying, as may be desired, from 5 to 40 percent by volume of the total resultant mass. The fabric material is preferably inserted in the form of a multitude of small disconnected pieces of approximately 1/2 to 3 inches over-all or in length. Nylon yarn pieces of such length is preferably used. The exact resultant chemical action between the particles of nylon and the aluminum chips and the elastomeric matrix, which matrix is preferably neoprene, is not fully understood. Applicant has discovered that the nylon particles in the matrix having the aluminum pieces therein greatly improves the product. The nylon does not become completely dissolved in the matrix, but substantially retains its form in the finished cured product. There is a marvelous resultant chemical action caused by the aluminum and the nylon or synthetic pieces being in the matrix, as shown in the finished product.
By the addition to Applicant's synthetic neoprene matrix, having aluminum pieces interspersed therein, of nylon fabric particles and which nylon particles are of any of a group of synthetic long chain polymeric amides with recurring amid groups. Instead of nylon, polyester, orlon or rayon can be used. By the addition of such fabric particles, applicant has thereby greatly improved the flexibility and strength of his matrix. The addition of nylon and such other disconnected pieces in and to the synthetic neoprene rubber, and which rubber is produced by the polymerization of chloroprene, also produces a further chemical reaction for the first time, as far as known, namely, a successful and strong bond of the aluminum particles in and to that aluminum pieces-synthetic rubber combination matrix is produced on aeration curing of the matrix. Also it has been discovered that the addition of those nylon pieces results in giving that matrix a much greater adhesive quality, adapting it to stick better to the surface to which the matrix is applied without having to add a cementing material. The use of disconnected pieces of Dacron and Orlon, instead of Nylon, simularly accomplishes similar beneficial results, as Applicant is not to be limited to the use of pieces of one synthetic material, namely, nylon.
As a result of that bonding and adhesive characteristics, resulting from the insert of nylon fabric and other synthetic fibrous particles in the matrix, it is now possible to bond larger pieces of aluminum than heretofore, as well as a myriad of small aluminum mill-cuttings, shavings or chips. Now different sizes and kind of pieces of aluminum may be successfully bonded in and to such a matrix, without limitation as to size, where the pieces are bendable, upwards to approximately 3 inches in one direction. Non-bendable pieces of aluminum can be used, in my matrix, including regular shaped pieces, such as die-stamped configurations, having sizes ranging upwards of 11/2 inches in one direction and of any thickness within reason from one two-hundred fifty-sixths of an inch to three-eighths of an inch.
In other words, by my invention it is now feasible to suitably bond most any size pieces of aluminum pieces into an elastomeric matrix, and with those pieces of either regular or irregular sizes or shapes, and with the pieces either bendable or non-bendable and of serrated or even edges. In the making of non-slip surfaces, it is, as a result of this invention, now better possible to take advantage of the natural inherent anti-slip properties of aluminum when wet, even on ice, by having larger than mill-cutting pieces of aluminum in such a matrix and finished product.
It is therefore an object of this invention to provide a novel and improved anti-slip surface formed as a pad, sheet or layer, which will be hereinafter generally referred to as an anti-slip surface which takes advantage of the inherent properties of aluminum of resistance to slipping, with the structure of the anti-slip surface being formed in a manner which permits the same to be easily applied to the surface of the sole of a fishing boot or the like.
Another object of the invention is to provide a novel and improved anti-slip surface for boots and the like of an elastomeric matrix, with the aluminum pieces of the form, as in mill-cuttings, which are either inherently interlocked into the matrix, in an arrangement which effectively holds and retains the same while at the same time posing an effective antislip outer surface, or are of a form larger than mill-cuttings and without such inherent interlocking ability.
Another object of the invention is to provide, in a novel and improved anti-slip surface, the combining of aluminum particles in an elastomeric matrix, with said particles of a form which may be easily and economically obtained, such as machine cuttings normally considered as a waste product, or other cuttings, as die-stamped pieces.
Another object of my invention is to provide a novel and improved anti-slip surface which can be made with any of a number of easily obtained elastomers, including natural rubber, without the need for special processes and apparatus to cure the elastomer to the resiliency desired.
Another object of this invention is to provide a novel and improved elastomeric anti-slip surface by interblending aluminum pieces in an uncured or unfinished elastomer matrix which may be adapted for immediate application or for finishing into a boot surface or set aside for a substantial period of time, the same having a good shelf life for subsequent use as desired.
Another object of this invention is to provide an improved anti-slip surface by combining an elastomer and pieces of disconnected synthetic fabric particles of such fibers as nylon, polyester, orlon and rayon, and with aluminum pieces, wherein a chemical action is obtained between the aluminum pieces and the fabric particles and the elastomer to facilitate and inherently bond the aluminum particles therein and thereto and also to finish the elastomer into a dense body of selected resilience without the addition of special oxides and the like being required in the final product.
The foregoing and other objects will be apparent from the following description of the invention, setting forth the various processes, blends and combinations, and the selected steps, sequences and operations, as hereinafter explained in detail and set forth in the appended claims, and in the accompanying drawings diagrammatically illustrating, wherein:
FIG. 1 is a plan view of an inverted boot showing my improved anti-slip surface applied thereto as a sole or layer; and
FIG. 2 is a cross-sectional view taken on the line 2--2 of FIG. 1, looking in the direction of the indicated arrows.
To provide an improved boot sole, 20, it is desirable to take advantage of the anti-slip property of aluminum. It was found that it is possible to have larger pieces of aluminum, 30 and 50, interspersed and embedded into a rubber matrix, in order to have said non-slip characteristics of the aluminum in greater quantities, than the heretofore waste aluminum mill shavings or cutting particles, because it is now possible by my novel combining of disconnected pieces of a synthetic fabric material 40 in the matrix having larger aluminum pieces therein to effect a sufficient bond to hold such larger pieces of aluminum therein, despite the continual distortion on flexing of the boot sole on use. It was discovered that using certain synthetic fabric pieces or particles, such as of nylon, in combination with an elastomeric matrix, such as of a neoprene adhesive having aluminum pieces therein, produces a strong bonding or holding of said aluminum particles as a part of the finished product, in the cases of different sizes and shapes of aluminum pieces, even of regular and non-bendable configuration. It is, therefore, now possible to bond different size and kinds of pieces of aluminum in such a matrix, reasonably without limitation, where the pieces 50 are bendable of upwards of approximately 3 inches in length. Non-bendable pieces of aluminum 30 may be used in that matrix. Even regular shaped pieces, such as die-stamped configurations, 30, may be used, and non-bendable other shaped pieces, and having sizes ranging upwards of 11/2 inches in one direction and of any thickness from one two hundred fifty-sixths of an inch to three-eighths of an inch.
The use of a myriad quantity of fine aluminum shavings, from such as mill cuttings, 10, will be more successfully adhesively bonded as a result of the presence of the nylon fabric particles in the matrix, than previously.
The quantity or amount of aluminum pieces impregnated into the elastomeric matrix may be varied considerably, or preferably from 20 percent to 60 percent by volume of the total resultant mass.
It was found that where natural rubber was used as the elastomer that the proportion of aluminum pieces to the elastomer, measured volumetrically, varies from a maximum of about 40 percent as the maximum amount of the pieces which could be put into the rubber, while the minimum amount to have a non-slip surface is approximately 10 percent of the total combined volume. If an amount exceeding the maximum of 40 percent is used, the final product does not have adequate strength. If the percentage of the articles in the mass is less than 10 percent of the combined volume, the anti-slip characteristic is significantly diminshed. diminished.
Where a synthetic resin elastomer is used for the matrix, of a type such as Neoprene, the volume of the particles may be substantially increased to approximately as much as sixty per cent of the combined volume, and providing not less than 10 percent thereof. These percentages are rough approximations. The actual desired amount of aluminum particles to the elastomer may be varied somewhat depending upon the average size of the particles, the thickness of the particles and their over-all configuration. A desirable blend of any given type of elastomer may be easily obtained by simple experiment within the ranges stated.
It is desirable and an essential property of the elastomer is that it must be in a liquid or putty form, whether uncured or cutback with a solvent, so that it is capable of permitting the aluminum chips or pieces to be blended into the matrix formed thereof. Additionally, the elastomer must be capable of being cured or finished, as by vaporization of the solvent, if of that type, or of oxidation if of another type, to a final condition wherein it is tough but flexible. The degree of flexibility of this cured product, with the aluminum pieces interspersed therein, may vary considerably, but it is desirable to provide an elastomer which will flex when the product is affixed to a flexible boot sole. The range of curing can be from a moderately rigid member to one which is quite pliable, with the durometer of the cured impregnated material varying from 20 to 80. It is to be noted that conventional fully cured hard rubber is generally somewhat too hard for use of the present invention.
By the term Durometer measurement is meant that well known Shore scale measurement of hardness or flexibility of Applicant's matrix. Such measurement is made to determine the relative resistance of the surface, of the matrix to indentation by the indentor of the Shore A instrument, of specified dimensions under a specified load. Said Shore A instrument, so far as known, is widely used for measuring such hardness of rubber and is an accepted reliable standard scale test or measurement instrument in the industry. Same is explained in the 1963 copyrighted booklet of E. I. DuPont De Nemours and Company, Elastomer Chemicals Department, of Wilmington, Del., entitled "The Language of Rubber."
A necessary characteristic of applicant's elastomer resides in the property of being capable of being applied to the sole of a boot or shoe while it is in a liquid or putty state and before its final cure or finish, or if it is cured or finished as a pad it must be capable of being applied to a shoe sole by any suitable adhesive, and capable of yielding with the shoe sole without being torn lose.
Elastomers which I have used, representative of the following examples, include, first, natural rubber which was obtained as a sheet of raw uncured such material, with one type being a natural raw uncured rubber, and a second type being a sheet of uncured rubber stock having lamp black therein and commonly known to the trade as tire retreading camel-back. Said natural rubbers used were by one method separately prepared by dissolving them in solvents, such as methyl ethyl ketone, into a semi-liquid state wherein the aluminum particles and nylon pieces could be mixed. The particles were interblended in that resultant natural rubber semi-liquid mass.
Another type of elastomer used has been a synthetic Neoprene elastomer, and which elastomer was obtained as a Latex, commonly known to the trade as the E. I. DuPont De Nemours Company's Neoprene Latex numbers 650, 635 and 601a. These latter elastomer types are milk-like substances.
Another type of synthetic elastomer has been a polysulphide liquid polymer, produced by Thiokol Chemical Corporation, and designated as Thiokol's LP-2, of said corporation, being a comparatively thick viscous polymer matrix, in its uncured form; produced in two components to be mixed together, with one component being a thick liquid and the other a thick paste.
Another type of elastomer used was substantially a cured Neoprene which had been dissolved in some solvent, probably methyl ethyl ketone, as an adhesive, wherein the adhesive material was fluid enough to mix with the aluminum chips and synthetic fabric material pieces.
A further elastomer consisted of a Polyurethane dissolved in methyl ethyl ketone, which finished out after being mixed with nylon or other synthetic material pieces and aluminum chips; all as hereinafter set forth more specifically in the following examples.
The following examples are given to assist in understanding my invention, but I am not to be restricted by the specific materials or procedures therein, as they are merely exemplary of the invention.
EXAMPLE 1
About 3 pounds of 35 durometer uncured camel-back sheet of natural rubber, of the type used in tire retreading, was dissolved in carbon disulphide, in approximately equal proportions, forming a thick gel. To this gel, by volume, one part of such aluminum pieces and one part of disconnected nylon fabric particles was stir blended with about three parts of the gel. That resultant mixture matrix gel was then poured into a sole shaped mold of the thickness of onefourth of an inch. There was a natural evaporation of the carbon disulphide occured and the rubber in the mold was cured by placing the mold and contents in an electric hot plate pressure machine at a temperature not exceeding 240° and at a pressure on the mold contents of not exceeding 20 pounds for approximately 8 minutes. The sole pad was allowed to remain in the mold for approximately 8 minutes and was then removed. The durometer of this final sole product was approximately 30. The final result was softer than the original stock, but it was sufficiently strong and coherent to form a sole which could be affixed as a sole to the bottom of a boot.
EXAMPLE 2
The same as example one, with that heat application, excepting that no pressure was applied to the sole during that cure. The cure appeared to be substantially the same as that previously obtained with pressure except that the appearance of the final product was not as smooth, and it was of a resultant durometer of about 25.
EXAMPLE 3
The same as example one, excepting a pressure of only approximately 100 pounds was applied to the mold contents without any application of heat. The sole was removed from the mold then and allowed to air cure for five days time, when it was found to be of about 20 durometer and sufficiently rigid to be secured to and used as the sole of a boot.
From the above examples, it is obvious that a technician skilled in the rubber fabricating art can select such milled or suitable other aluminum pieces and nylon particles, interblend the quantities of the same in the rubber, as by dissolving the rubber into a gel or liquid and subsequently curing the same into a selected comparatively soft condition of a boot sole, where the sole will bend over and in adherence of the uneven contour of stones which the wearer steps upon. Through such adherence, the aluminum surfaces of the pieces in the sole and exposed to the objects stepped on facilitate gripping that object and minimize the chances of the wearer slipping.
In the following examples the use of synthetic rubber is set forth. Synthetic resins having elastomeric properties and are commonly referred to as synthetic rubber.
EXAMPLE 4
The Polysulphide liquid polymer identified as Thiokol LP2, manufactured by Thiokol Chemical Corporation, of Trenton, N.J., provided as a two component material: the resin and the accelerator. According to recommended practice, 15 parts of resin to one part of accelerator, by weight, were blended together to produce a polysulphide rubber at room temperature. A small batch of this material, approximately 6 fluid ounces, was mixed and prepared, aluminum particles and a quantity of disconnected nylon yarn pieces were immediately added to that blend matrix mixture before the accelerator began to act. The amount of those aluminum particles so added was at least about 25 percent by volume and not over 40 percent by volume compared to the amount of that rubber mass. About 15 percent by volume of nylon yarn pieces were added. That matrix, having aluminum particle and nylon mixture, blend was then substantially immediately spread-on applied to the sole of an inverted boot, as a thick matt, and it adhered well to the surface of that boot sole and was set in approximately 30 minutes. It substantially completely air-cured in approximately 4 hours, without any heat or pressure application at room temperature, resulting in a resilient and flexible non-slip surface of about 50 durometer having aluminum particles impregnated therein. In this example the setting occurs quite rapidly and for that reason it is not practical to disperse more than about 40 percent of the aluminum and nylon particles by volume into that LP2 matrix rubber. A subsequent test indicated that when 50 percent of such particles by volume was added to such an LP2 Thiokol mixture the final product did not have adequate strength to serve the desired purpose and was too difficult to manage.
EXAMPLE 5
A solution of cured Neoprene rubber, of the type dissolved in volatile substances as an adhesive, was next used. It was of the type obtained commercially from the Roberts Company, of Monrovia, Calif., which merchandizes the material as a neoprene adhesive glue under the trade name of Roberts' "Anchor Weld." Such Neoprene liquid rubber solution was mixed with approximately about: 10 percent clay filler, 40 percent quantity of aluminum pieces, 20 percent quantity of disconnected nylon yarn pieces, and 5 percent of spray-type "Nylo" rubber cement, and that mixture was then immediately hermatically air sealed in a can. When the can was opened later and contents stir-mixed and then applied to the sole of an inverted boot, the matrix set in approximately 10 minutes and the boot sole was air-cured and ready for use in 48 hours. This method I found to be a preferred one. This canned matrix may be kept for many months before being opened. In this instance I use relatively small pieces of disconnected nylon yarn, of the type and approximate diameter size of the strands as used thereof in the making of nylon shag carpeting, and with the individual nylon yarn pieces each being about one to two inches in length. The aluminum paricles were strongly bonded and held by this neoprene matrix as a part thereof. I uses used small quantity of suitable clay filler in the matrix along with the nylon and aluminum pieces, so that the final sole product was about 60 durometer. The new sole was sufficiently elastic, with the aluminum and nylon particles bonded in the boot sole when in use and provided a strong and effective nonslip sole surface on that boot sole.
EXAMPLE 6
Similar to the preceding Example 5, a volatile solution of cured neoprene adhesive rubber, such as Roberts' Anchor Weld, was used. To that solution was approximately mixed: 10 percent of clay filler, 40 percent of aluminum pieces and 15 percent of disconnected pieces of about 2 inch length fabric, and which fabric was 75 percent synthetic rayon and 25 percent cotton yarn, and 10 percent of relatively thin spray-rubber-cement, and on such mixing of the material as a matrix it was hermatically air sealed in a can. On opening the can later, the matrix was stirred and then applied to the sole of an inverted boot and it set rapidly in a matter of about 30 minutes and as a sole addition was ready for use in about 48 hours. It was found that this matrix combination, with such a mostly synthetic and some cotton yarn material, made a very substantially strong resultant aluminum-piece mixture non-slip sole product, as well as one which adhered well to the sole and was flexible and did a very good job of bonding the aluminum chips into the final product. It will be apparent that other fabric material, such as of hemp or cotton fabric pieces could be used, instead of synthetic fabric pieces within the teaching of my invention.
EXAMPLE 7
An uncured neoprene latex, manufactured by E. I. DuPont De Nemours, Inc., under the trade name designation of Neoprene Latex 635, provided as an uncured milklike liquid, was used. Such aluminum particles were mix-blended with this latex uncured liquid in about equal parts by volume. About 10 percent of volume of an anti-oxidant was added, and about 15 percent of volume of a clay filler was added to the mixture to provide body. To the mixture I added a small quantity of about 10 percent of volume of nylon fabric pieces to provide a stronger body without interfering with flexibility. That blend mixture was poured into a suitable sole mold and was then allowed to set and cure at room temperature for about a day, when the material was set in the mold into its form, and then it was removed from the mold and after 2 more days total room temperature curing period the curing was completed to the final product of about 60 durometer. The product so formed was then a good anti-slip surface or pad capable of easily being cemented or attached as a sole to the sole of a boot. The type and amount of clay filler and nylon pieces used could be varied, such as increased, to have a quicker curing and better flexibility, among others.
In the use of neoprene the use of consistently larger quantities of aluminum chips can be interblended into the mix, as compared with a matrix mix of natural rubber heretofore disclosed.
EXAMPLE 8
Neoprene Latex No. 601a of said DuPont Company, was used, as in Example 7, in equal proportion of aluminum pieces and a small quantity of nylon pieces were added, with some clay and an anti-oxident. That mixture was immediately spread-applied directly to the inverted prior rubber cemented sole surface of a rubber boot. That neoprene mixture on such application was permitted to oxidize in the air, and it was discovered that the cure was comparatively rapid, and a blended resultant mass thereof was formed approximately five-eighths of an inch thick on the inverted boot sole surface, indicated as 20 of FIG. 1. The material was set in four hours and was fully oxidized or air cured at about 50 durometer hardness in approximately 72 hours, in the form of my flexible anti-slip aluminum impregnated surface ready for use as the sole of the boot.
In the development of the invention, as set forth in the foregoing examples, it became apparent that some form of Neoprene would be the preferred type of elastomer. Investigations were made as to the manner in which the neoprene aluminum-nylon blend would cure, on aeration at room temperature, from the unpolymerized state in the milk-like 601a, 635 and 650 elastomers and from the dissolved neoprene rubber adhesive type of elastomer, such as the Anchor-Weld type. It appears that the usual curing agents for neoprene are metal oxides, and that such curing agents are available for the purpose. However, it was discovered that, in working with the Latex Neoprene, that oxides, in the form of thin oxide coatings on the aluminum pieces, were sufficient to effect the cure without the addition of the commercial curing agents, when the neoprene latex, nylon pieces and aluminum pieces mixed mass was exposed to the air. This was even more so when a cured Neoprene adhesive, as Anchor-Weld, was used.
EXAMPLE 9
The same as example seven, except that the latex used was said DuPont's milk-like uncured latex number 650, a neoprene latex similar to the latex 635 of Example 7, excepting, insofar as the test was concerned, the viscosity of the No. 650 material was much higher and so the blend was easier to handle and spread; and, also, use of the No. 650 material with the aluminum pieces and nylon pieces blend oxidized faster, requiring less time to get the desired completely cured substantially similar product, in about one-half the time as that set forth in example seven. I also spread this blend directly onto a rubber pre-cemented sole of a boot where it air cured successfully into a 60 durometer sole in 3 days.
From the foregoing examples and disclosure, it is apparent that such aluminum pieces 10, 30 and 50 and nylon fabric pieces 40 can be interblended with other types of synthetic elastomers which have the basic properties suitable for the purpose at hand. It is known that excellent tough and elastic elastomers can be obtained from synthetic resins, such as polyurethane and Butyl rubber. Butyl rubber can be dissolved in a manner very similar to natural rubber, and it follows that this material can also be mixed with the aluminum pieces and nylon pieces.
The addition of the disconnected pieces of synthetic fabric material, as explained, such as nylon and orlon, produces a chemical reaction, which is not fully understood by applicant, except, to say that said myriad of disconnected pieces, on mixture in the matrix and before aeration curing, also become softened and are distributed throughout the matrix and they effect, by causing an increased flexibility, a stronger matrix, a better adhesive characteristic of the matrix for application thereof to any surface, and also effect a stronger and more effective bonding of the aluminum pieces in and to the matrix, as a result, than has been accomplished heretofore without the use of such synthetic pieces interspersed in the matrix. The addition of the myriad of such disconnected synthetic fabric material pieces 40 to the matrix combination, with the aluminum chips, is an indispensable part of said matrix combination and of the novelty of this invention.
I do not wish to be limited, in my matrix combinations, to the use of nylon fabric pieces, as other synthetic fibers can be used instead and as well, such as Rayon, Dacron or Orlon fibers. Nylon, generally, is a synthetic fiber from any of a group of synthetic long-chain polymeric amides with recurring amide groups. Orlon, generally, is a synthetic acrylic fiber derived from a compound of hydrogen cyanide and acetelyne. Dacron, generally, is a polyester fiber of any of several polymeric resins and it may similarly also be used in my combinations. Rayon is a synthetic fiber made from pressing cellulose accetate or other cellulose solution through small openings and solidifying it as filaments. When the same quantity of Rayon, Dacron or Orlon yarn is used, in my matrix, for example, instead of Nylon, in the foregoing examples, similar beneficial increased strength, bonding, flexibility and adhesiveness of the matrix results occur.
With relation to the chemical reaction of the fabric pieces, of either Nylon, orlon, dacron or rayon, as explained, and previously stated as not fully understood, it should be mentioned that said chemical reaction affects the undesireable oxide coating normally present on the unwashed aluminum pieces, which coating deters bonding rubber to the surface of the aluminum pieces;--meaning, such chemical component reaction of the nylon pieces, for example, apparently causes a taking of that deterrent oxide coating into solution or so-called "cleans" that coating from the aluminum pieces, and also that chemical reaction effects or deposits a so-called aluminous film on the aluminum pieces resulting from the thus resultantly formed hydrolized solution. The U.S. Pat. to Beebe, No. 2,336,388, explains the bonding of rubber to aluminum, by an extra preparatory separate step; but by my novel use of such as Nylon fabric disconnected pieces, I accomplish that chemical reaction as a part of my novel one-step matrix composition mixture. As mentioned heretofore, my matrix is also made more adhesive and stronger and more flexible by that same chemical reaction, than before without said synthetic pieces in the matrix. It should be understood that there are also other synthetic material pieces that could be used within the teaching of my invention, for those purposes, in addition to the ones I have mentioned, to accomplish the purposes heretofore explained.
It will be apparent that many changes and modifications can be made within the teaching of the hereinbefore disclosed invention, such as by the use of hemp, or cotton fabric pieces instead of the synthetic pieces mentioned, and, therefore, I wish to be bound only by the hereunto appended claims.
The portion of the term of the patent, to be granted on this application, subsequent to Mar. 30, 1988, is, therefore, hereby disclaimed.
Fishermen encounter severe problems in stream fishing particularly, when their boots or shoes become wet in wading the stream, of slipping on wet rocks, which, late in the summer, have a slime, moss or algae thereon.
It has been discovered that aluminum has an inherent characteristic of being non-slip when wet. Aluminum plates have been at times clamped onto the sole of a boot, but they have been found to be cumbersome and difficult to hold onto the soles.
Applicant has heretofore perfected the use of a myriad of irregular waste aluminum particle shavings or mill-cutting chips interspersed in a quantity of elastomer or matrix, and wherein the aluminum chips are adhesively and/or mechanically bonded and held in place therein. Applicant has provided an elastomer on aeration to cure or finish into a resilient elastomeric state.
Pieces of aluminum larger than mill-cuttings have not heretofore been successfully bonded to that type of an elastomer, as they have become loose and thus were lost on flexing of the elastomer.
Applicant has now perfected and used pieces of aluminum larger than mill cuttings, including regular shaped pieces, in bonding them successfully into that type of a matrix by the addition of disconnected pieces of a synthetic fabric material as part of the filler of his elastomeric matrix, in combination with such larger pieces. Throughout this application Applicant will generally refer to such fabric material by their trade names, for convenience. He has discovered that the addition, for example, of pieces of nylon fabric material in his matrix, in combination with such aluminum pieces therein, causes a definite bonding of those larger aluminum pieces in and to his matrix.
This invention comprises, in essence, the combination of an elastomeric matrix material of natural or artificial rubber, such as of a neoprene liquid solution capable of self-curing on exposure to the atmosphere, having a quantity of various sizes or dimensions of aluminum particles or pieces interspersed therein and having a quantity of disconnected synthetic fabric pieces also interspersed therein. The quantity and proportion of the aluminum pieces can vary from approximately 20 to 60 percent by volume of the total resultant mass, and with the quantity of such synthetic as nylon pieces therein also varying, as may be desired, from 5 to 40 percent by volume of the total resultant mass. The fabric material is preferably inserted in the form of a multitude of small disconnected pieces of approximately 1/2 to 3 inches over-all or in length. Nylon yarn pieces of such length is preferably used. The exact resultant chemical action between the particles of nylon and the aluminum chips and the elastomeric matrix, which matrix is preferably neoprene, is not fully understood. Applicant has discovered that the nylon particles in the matrix having the aluminum pieces therein greatly improves the product. The nylon does not become completely dissolved in the matrix, but substantially retains its form in the finished cured product. There is a marvelous resultant chemical action caused by the aluminum and the nylon or synthetic pieces being in the matrix, as shown in the finished product.
By the addition to Applicant's synthetic neoprene matrix, having aluminum pieces interspersed therein, of nylon fabric particles and which nylon particles are of any of a group of synthetic long chain polymeric amides with recurring amid groups. Instead of nylon, polyester, orlon or rayon can be used. By the addition of such fabric particles, applicant has thereby greatly improved the flexibility and strength of his matrix. The addition of nylon and such other disconnected pieces in and to the synthetic neoprene rubber, and which rubber is produced by the polymerization of chloroprene, also produces a further chemical reaction for the first time, as far as known, namely, a successful and strong bond of the aluminum particles in and to that aluminum pieces-synthetic rubber combination matrix is produced on aeration curing of the matrix. Also it has been discovered that the addition of those nylon pieces results in giving that matrix a much greater adhesive quality, adapting it to stick better to the surface to which the matrix is applied without having to add a cementing material. The use of disconnected pieces of Dacron and Orlon, instead of Nylon, simularly accomplishes similar beneficial results, as Applicant is not to be limited to the use of pieces of one synthetic material, namely, nylon.
As a result of that bonding and adhesive characteristics, resulting from the insert of nylon fabric and other synthetic fibrous particles in the matrix, it is now possible to bond larger pieces of aluminum than heretofore, as well as a myriad of small aluminum mill-cuttings, shavings or chips. Now different sizes and kind of pieces of aluminum may be successfully bonded in and to such a matrix, without limitation as to size, where the pieces are bendable, upwards to approximately 3 inches in one direction. Non-bendable pieces of aluminum can be used, in my matrix, including regular shaped pieces, such as die-stamped configurations, having sizes ranging upwards of 11/2 inches in one direction and of any thickness within reason from one two-hundred fifty-sixths of an inch to three-eighths of an inch.
In other words, by my invention it is now feasible to suitably bond most any size pieces of aluminum pieces into an elastomeric matrix, and with those pieces of either regular or irregular sizes or shapes, and with the pieces either bendable or non-bendable and of serrated or even edges. In the making of non-slip surfaces, it is, as a result of this invention, now better possible to take advantage of the natural inherent anti-slip properties of aluminum when wet, even on ice, by having larger than mill-cutting pieces of aluminum in such a matrix and finished product.
It is therefore an object of this invention to provide a novel and improved anti-slip surface formed as a pad, sheet or layer, which will be hereinafter generally referred to as an anti-slip surface which takes advantage of the inherent properties of aluminum of resistance to slipping, with the structure of the anti-slip surface being formed in a manner which permits the same to be easily applied to the surface of the sole of a fishing boot or the like.
Another object of the invention is to provide a novel and improved anti-slip surface for boots and the like of an elastomeric matrix, with the aluminum pieces of the form, as in mill-cuttings, which are either inherently interlocked into the matrix, in an arrangement which effectively holds and retains the same while at the same time posing an effective antislip outer surface, or are of a form larger than mill-cuttings and without such inherent interlocking ability.
Another object of the invention is to provide, in a novel and improved anti-slip surface, the combining of aluminum particles in an elastomeric matrix, with said particles of a form which may be easily and economically obtained, such as machine cuttings normally considered as a waste product, or other cuttings, as die-stamped pieces.
Another object of my invention is to provide a novel and improved anti-slip surface which can be made with any of a number of easily obtained elastomers, including natural rubber, without the need for special processes and apparatus to cure the elastomer to the resiliency desired.
Another object of this invention is to provide a novel and improved elastomeric anti-slip surface by interblending aluminum pieces in an uncured or unfinished elastomer matrix which may be adapted for immediate application or for finishing into a boot surface or set aside for a substantial period of time, the same having a good shelf life for subsequent use as desired.
Another object of this invention is to provide an improved anti-slip surface by combining an elastomer and pieces of disconnected synthetic fabric particles of such fibers as nylon, polyester, orlon and rayon, and with aluminum pieces, wherein a chemical action is obtained between the aluminum pieces and the fabric particles and the elastomer to facilitate and inherently bond the aluminum particles therein and thereto and also to finish the elastomer into a dense body of selected resilience without the addition of special oxides and the like being required in the final product.
The foregoing and other objects will be apparent from the following description of the invention, setting forth the various processes, blends and combinations, and the selected steps, sequences and operations, as hereinafter explained in detail and set forth in the appended claims, and in the accompanying drawings diagrammatically illustrating, wherein:
FIG. 1 is a plan view of an inverted boot showing my improved anti-slip surface applied thereto as a sole or layer; and
FIG. 2 is a cross-sectional view taken on the line 2--2 of FIG. 1, looking in the direction of the indicated arrows.
To provide an improved boot sole, 20, it is desirable to take advantage of the anti-slip property of aluminum. It was found that it is possible to have larger pieces of aluminum, 30 and 50, interspersed and embedded into a rubber matrix, in order to have said non-slip characteristics of the aluminum in greater quantities, than the heretofore waste aluminum mill shavings or cutting particles, because it is now possible by my novel combining of disconnected pieces of a synthetic fabric material 40 in the matrix having larger aluminum pieces therein to effect a sufficient bond to hold such larger pieces of aluminum therein, despite the continual distortion on flexing of the boot sole on use. It was discovered that using certain synthetic fabric pieces or particles, such as of nylon, in combination with an elastomeric matrix, such as of a neoprene adhesive having aluminum pieces therein, produces a strong bonding or holding of said aluminum particles as a part of the finished product, in the cases of different sizes and shapes of aluminum pieces, even of regular and non-bendable configuration. It is, therefore, now possible to bond different size and kinds of pieces of aluminum in such a matrix, reasonably without limitation, where the pieces 50 are bendable of upwards of approximately 3 inches in length. Non-bendable pieces of aluminum 30 may be used in that matrix. Even regular shaped pieces, such as die-stamped configurations, 30, may be used, and non-bendable other shaped pieces, and having sizes ranging upwards of 11/2 inches in one direction and of any thickness from one two hundred fifty-sixths of an inch to three-eighths of an inch.
The use of a myriad quantity of fine aluminum shavings, from such as mill cuttings, 10, will be more successfully adhesively bonded as a result of the presence of the nylon fabric particles in the matrix, than previously.
The quantity or amount of aluminum pieces impregnated into the elastomeric matrix may be varied considerably, or preferably from 20 percent to 60 percent by volume of the total resultant mass.
It was found that where natural rubber was used as the elastomer that the proportion of aluminum pieces to the elastomer, measured volumetrically, varies from a maximum of about 40 percent as the maximum amount of the pieces which could be put into the rubber, while the minimum amount to have a non-slip surface is approximately 10 percent of the total combined volume. If an amount exceeding the maximum of 40 percent is used, the final product does not have adequate strength. If the percentage of the articles in the mass is less than 10 percent of the combined volume, the anti-slip characteristic is significantly diminshed. diminished.
Where a synthetic resin elastomer is used for the matrix, of a type such as Neoprene, the volume of the particles may be substantially increased to approximately as much as sixty per cent of the combined volume, and providing not less than 10 percent thereof. These percentages are rough approximations. The actual desired amount of aluminum particles to the elastomer may be varied somewhat depending upon the average size of the particles, the thickness of the particles and their over-all configuration. A desirable blend of any given type of elastomer may be easily obtained by simple experiment within the ranges stated.
It is desirable and an essential property of the elastomer is that it must be in a liquid or putty form, whether uncured or cutback with a solvent, so that it is capable of permitting the aluminum chips or pieces to be blended into the matrix formed thereof. Additionally, the elastomer must be capable of being cured or finished, as by vaporization of the solvent, if of that type, or of oxidation if of another type, to a final condition wherein it is tough but flexible. The degree of flexibility of this cured product, with the aluminum pieces interspersed therein, may vary considerably, but it is desirable to provide an elastomer which will flex when the product is affixed to a flexible boot sole. The range of curing can be from a moderately rigid member to one which is quite pliable, with the durometer of the cured impregnated material varying from 20 to 80. It is to be noted that conventional fully cured hard rubber is generally somewhat too hard for use of the present invention.
By the term Durometer measurement is meant that well known Shore scale measurement of hardness or flexibility of Applicant's matrix. Such measurement is made to determine the relative resistance of the surface, of the matrix to indentation by the indentor of the Shore A instrument, of specified dimensions under a specified load. Said Shore A instrument, so far as known, is widely used for measuring such hardness of rubber and is an accepted reliable standard scale test or measurement instrument in the industry. Same is explained in the 1963 copyrighted booklet of E. I. DuPont De Nemours and Company, Elastomer Chemicals Department, of Wilmington, Del., entitled "The Language of Rubber."
A necessary characteristic of applicant's elastomer resides in the property of being capable of being applied to the sole of a boot or shoe while it is in a liquid or putty state and before its final cure or finish, or if it is cured or finished as a pad it must be capable of being applied to a shoe sole by any suitable adhesive, and capable of yielding with the shoe sole without being torn lose.
Elastomers which I have used, representative of the following examples, include, first, natural rubber which was obtained as a sheet of raw uncured such material, with one type being a natural raw uncured rubber, and a second type being a sheet of uncured rubber stock having lamp black therein and commonly known to the trade as tire retreading camel-back. Said natural rubbers used were by one method separately prepared by dissolving them in solvents, such as methyl ethyl ketone, into a semi-liquid state wherein the aluminum particles and nylon pieces could be mixed. The particles were interblended in that resultant natural rubber semi-liquid mass.
Another type of elastomer used has been a synthetic Neoprene elastomer, and which elastomer was obtained as a Latex, commonly known to the trade as the E. I. DuPont De Nemours Company's Neoprene Latex numbers 650, 635 and 601a. These latter elastomer types are milk-like substances.
Another type of synthetic elastomer has been a polysulphide liquid polymer, produced by Thiokol Chemical Corporation, and designated as Thiokol's LP-2, of said corporation, being a comparatively thick viscous polymer matrix, in its uncured form; produced in two components to be mixed together, with one component being a thick liquid and the other a thick paste.
Another type of elastomer used was substantially a cured Neoprene which had been dissolved in some solvent, probably methyl ethyl ketone, as an adhesive, wherein the adhesive material was fluid enough to mix with the aluminum chips and synthetic fabric material pieces.
A further elastomer consisted of a Polyurethane dissolved in methyl ethyl ketone, which finished out after being mixed with nylon or other synthetic material pieces and aluminum chips; all as hereinafter set forth more specifically in the following examples.
The following examples are given to assist in understanding my invention, but I am not to be restricted by the specific materials or procedures therein, as they are merely exemplary of the invention.
EXAMPLE 1
About 3 pounds of 35 durometer uncured camel-back sheet of natural rubber, of the type used in tire retreading, was dissolved in carbon disulphide, in approximately equal proportions, forming a thick gel. To this gel, by volume, one part of such aluminum pieces and one part of disconnected nylon fabric particles was stir blended with about three parts of the gel. That resultant mixture matrix gel was then poured into a sole shaped mold of the thickness of onefourth of an inch. There was a natural evaporation of the carbon disulphide occured and the rubber in the mold was cured by placing the mold and contents in an electric hot plate pressure machine at a temperature not exceeding 240° and at a pressure on the mold contents of not exceeding 20 pounds for approximately 8 minutes. The sole pad was allowed to remain in the mold for approximately 8 minutes and was then removed. The durometer of this final sole product was approximately 30. The final result was softer than the original stock, but it was sufficiently strong and coherent to form a sole which could be affixed as a sole to the bottom of a boot.
EXAMPLE 2
The same as example one, with that heat application, excepting that no pressure was applied to the sole during that cure. The cure appeared to be substantially the same as that previously obtained with pressure except that the appearance of the final product was not as smooth, and it was of a resultant durometer of about 25.
EXAMPLE 3
The same as example one, excepting a pressure of only approximately 100 pounds was applied to the mold contents without any application of heat. The sole was removed from the mold then and allowed to air cure for five days time, when it was found to be of about 20 durometer and sufficiently rigid to be secured to and used as the sole of a boot.
From the above examples, it is obvious that a technician skilled in the rubber fabricating art can select such milled or suitable other aluminum pieces and nylon particles, interblend the quantities of the same in the rubber, as by dissolving the rubber into a gel or liquid and subsequently curing the same into a selected comparatively soft condition of a boot sole, where the sole will bend over and in adherence of the uneven contour of stones which the wearer steps upon. Through such adherence, the aluminum surfaces of the pieces in the sole and exposed to the objects stepped on facilitate gripping that object and minimize the chances of the wearer slipping.
In the following examples the use of synthetic rubber is set forth. Synthetic resins having elastomeric properties and are commonly referred to as synthetic rubber.
EXAMPLE 4
The Polysulphide liquid polymer identified as Thiokol LP2, manufactured by Thiokol Chemical Corporation, of Trenton, N.J., provided as a two component material: the resin and the accelerator. According to recommended practice, 15 parts of resin to one part of accelerator, by weight, were blended together to produce a polysulphide rubber at room temperature. A small batch of this material, approximately 6 fluid ounces, was mixed and prepared, aluminum particles and a quantity of disconnected nylon yarn pieces were immediately added to that blend matrix mixture before the accelerator began to act. The amount of those aluminum particles so added was at least about 25 percent by volume and not over 40 percent by volume compared to the amount of that rubber mass. About 15 percent by volume of nylon yarn pieces were added. That matrix, having aluminum particle and nylon mixture, blend was then substantially immediately spread-on applied to the sole of an inverted boot, as a thick matt, and it adhered well to the surface of that boot sole and was set in approximately 30 minutes. It substantially completely air-cured in approximately 4 hours, without any heat or pressure application at room temperature, resulting in a resilient and flexible non-slip surface of about 50 durometer having aluminum particles impregnated therein. In this example the setting occurs quite rapidly and for that reason it is not practical to disperse more than about 40 percent of the aluminum and nylon particles by volume into that LP2 matrix rubber. A subsequent test indicated that when 50 percent of such particles by volume was added to such an LP2 Thiokol mixture the final product did not have adequate strength to serve the desired purpose and was too difficult to manage.
EXAMPLE 5
A solution of cured Neoprene rubber, of the type dissolved in volatile substances as an adhesive, was next used. It was of the type obtained commercially from the Roberts Company, of Monrovia, Calif., which merchandizes the material as a neoprene adhesive glue under the trade name of Roberts' "Anchor Weld." Such Neoprene liquid rubber solution was mixed with approximately about: 10 percent clay filler, 40 percent quantity of aluminum pieces, 20 percent quantity of disconnected nylon yarn pieces, and 5 percent of spray-type "Nylo" rubber cement, and that mixture was then immediately hermatically air sealed in a can. When the can was opened later and contents stir-mixed and then applied to the sole of an inverted boot, the matrix set in approximately 10 minutes and the boot sole was air-cured and ready for use in 48 hours. This method I found to be a preferred one. This canned matrix may be kept for many months before being opened. In this instance I use relatively small pieces of disconnected nylon yarn, of the type and approximate diameter size of the strands as used thereof in the making of nylon shag carpeting, and with the individual nylon yarn pieces each being about one to two inches in length. The aluminum paricles were strongly bonded and held by this neoprene matrix as a part thereof. I uses used small quantity of suitable clay filler in the matrix along with the nylon and aluminum pieces, so that the final sole product was about 60 durometer. The new sole was sufficiently elastic, with the aluminum and nylon particles bonded in the boot sole when in use and provided a strong and effective nonslip sole surface on that boot sole.
EXAMPLE 6
Similar to the preceding Example 5, a volatile solution of cured neoprene adhesive rubber, such as Roberts' Anchor Weld, was used. To that solution was approximately mixed: 10 percent of clay filler, 40 percent of aluminum pieces and 15 percent of disconnected pieces of about 2 inch length fabric, and which fabric was 75 percent synthetic rayon and 25 percent cotton yarn, and 10 percent of relatively thin spray-rubber-cement, and on such mixing of the material as a matrix it was hermatically air sealed in a can. On opening the can later, the matrix was stirred and then applied to the sole of an inverted boot and it set rapidly in a matter of about 30 minutes and as a sole addition was ready for use in about 48 hours. It was found that this matrix combination, with such a mostly synthetic and some cotton yarn material, made a very substantially strong resultant aluminum-piece mixture non-slip sole product, as well as one which adhered well to the sole and was flexible and did a very good job of bonding the aluminum chips into the final product. It will be apparent that other fabric material, such as of hemp or cotton fabric pieces could be used, instead of synthetic fabric pieces within the teaching of my invention.
EXAMPLE 7
An uncured neoprene latex, manufactured by E. I. DuPont De Nemours, Inc., under the trade name designation of Neoprene Latex 635, provided as an uncured milklike liquid, was used. Such aluminum particles were mix-blended with this latex uncured liquid in about equal parts by volume. About 10 percent of volume of an anti-oxidant was added, and about 15 percent of volume of a clay filler was added to the mixture to provide body. To the mixture I added a small quantity of about 10 percent of volume of nylon fabric pieces to provide a stronger body without interfering with flexibility. That blend mixture was poured into a suitable sole mold and was then allowed to set and cure at room temperature for about a day, when the material was set in the mold into its form, and then it was removed from the mold and after 2 more days total room temperature curing period the curing was completed to the final product of about 60 durometer. The product so formed was then a good anti-slip surface or pad capable of easily being cemented or attached as a sole to the sole of a boot. The type and amount of clay filler and nylon pieces used could be varied, such as increased, to have a quicker curing and better flexibility, among others.
In the use of neoprene the use of consistently larger quantities of aluminum chips can be interblended into the mix, as compared with a matrix mix of natural rubber heretofore disclosed.
EXAMPLE 8
Neoprene Latex No. 601a of said DuPont Company, was used, as in Example 7, in equal proportion of aluminum pieces and a small quantity of nylon pieces were added, with some clay and an anti-oxident. That mixture was immediately spread-applied directly to the inverted prior rubber cemented sole surface of a rubber boot. That neoprene mixture on such application was permitted to oxidize in the air, and it was discovered that the cure was comparatively rapid, and a blended resultant mass thereof was formed approximately five-eighths of an inch thick on the inverted boot sole surface, indicated as 20 of FIG. 1. The material was set in four hours and was fully oxidized or air cured at about 50 durometer hardness in approximately 72 hours, in the form of my flexible anti-slip aluminum impregnated surface ready for use as the sole of the boot.
In the development of the invention, as set forth in the foregoing examples, it became apparent that some form of Neoprene would be the preferred type of elastomer. Investigations were made as to the manner in which the neoprene aluminum-nylon blend would cure, on aeration at room temperature, from the unpolymerized state in the milk-like 601a, 635 and 650 elastomers and from the dissolved neoprene rubber adhesive type of elastomer, such as the Anchor-Weld type. It appears that the usual curing agents for neoprene are metal oxides, and that such curing agents are available for the purpose. However, it was discovered that, in working with the Latex Neoprene, that oxides, in the form of thin oxide coatings on the aluminum pieces, were sufficient to effect the cure without the addition of the commercial curing agents, when the neoprene latex, nylon pieces and aluminum pieces mixed mass was exposed to the air. This was even more so when a cured Neoprene adhesive, as Anchor-Weld, was used.
EXAMPLE 9
The same as example seven, except that the latex used was said DuPont's milk-like uncured latex number 650, a neoprene latex similar to the latex 635 of Example 7, excepting, insofar as the test was concerned, the viscosity of the No. 650 material was much higher and so the blend was easier to handle and spread; and, also, use of the No. 650 material with the aluminum pieces and nylon pieces blend oxidized faster, requiring less time to get the desired completely cured substantially similar product, in about one-half the time as that set forth in example seven. I also spread this blend directly onto a rubber pre-cemented sole of a boot where it air cured successfully into a 60 durometer sole in 3 days.
From the foregoing examples and disclosure, it is apparent that such aluminum pieces 10, 30 and 50 and nylon fabric pieces 40 can be interblended with other types of synthetic elastomers which have the basic properties suitable for the purpose at hand. It is known that excellent tough and elastic elastomers can be obtained from synthetic resins, such as polyurethane and Butyl rubber. Butyl rubber can be dissolved in a manner very similar to natural rubber, and it follows that this material can also be mixed with the aluminum pieces and nylon pieces.
The addition of the disconnected pieces of synthetic fabric material, as explained, such as nylon and orlon, produces a chemical reaction, which is not fully understood by applicant, except, to say that said myriad of disconnected pieces, on mixture in the matrix and before aeration curing, also become softened and are distributed throughout the matrix and they effect, by causing an increased flexibility, a stronger matrix, a better adhesive characteristic of the matrix for application thereof to any surface, and also effect a stronger and more effective bonding of the aluminum pieces in and to the matrix, as a result, than has been accomplished heretofore without the use of such synthetic pieces interspersed in the matrix. The addition of the myriad of such disconnected synthetic fabric material pieces 40 to the matrix combination, with the aluminum chips, is an indispensable part of said matrix combination and of the novelty of this invention.
I do not wish to be limited, in my matrix combinations, to the use of nylon fabric pieces, as other synthetic fibers can be used instead and as well, such as Rayon, Dacron or Orlon fibers. Nylon, generally, is a synthetic fiber from any of a group of synthetic long-chain polymeric amides with recurring amide groups. Orlon, generally, is a synthetic acrylic fiber derived from a compound of hydrogen cyanide and acetelyne. Dacron, generally, is a polyester fiber of any of several polymeric resins and it may similarly also be used in my combinations. Rayon is a synthetic fiber made from pressing cellulose accetate or other cellulose solution through small openings and solidifying it as filaments. When the same quantity of Rayon, Dacron or Orlon yarn is used, in my matrix, for example, instead of Nylon, in the foregoing examples, similar beneficial increased strength, bonding, flexibility and adhesiveness of the matrix results occur.
With relation to the chemical reaction of the fabric pieces, of either Nylon, orlon, dacron or rayon, as explained, and previously stated as not fully understood, it should be mentioned that said chemical reaction affects the undesireable oxide coating normally present on the unwashed aluminum pieces, which coating deters bonding rubber to the surface of the aluminum pieces;--meaning, such chemical component reaction of the nylon pieces, for example, apparently causes a taking of that deterrent oxide coating into solution or so-called "cleans" that coating from the aluminum pieces, and also that chemical reaction effects or deposits a so-called aluminous film on the aluminum pieces resulting from the thus resultantly formed hydrolized solution. The U.S. Pat. to Beebe, No. 2,336,388, explains the bonding of rubber to aluminum, by an extra preparatory separate step; but by my novel use of such as Nylon fabric disconnected pieces, I accomplish that chemical reaction as a part of my novel one-step matrix composition mixture. As mentioned heretofore, my matrix is also made more adhesive and stronger and more flexible by that same chemical reaction, than before without said synthetic pieces in the matrix. It should be understood that there are also other synthetic material pieces that could be used within the teaching of my invention, for those purposes, in addition to the ones I have mentioned, to accomplish the purposes heretofore explained.
It will be apparent that many changes and modifications can be made within the teaching of the hereinbefore disclosed invention, such as by the use of hemp, or cotton fabric pieces instead of the synthetic pieces mentioned, and, therefore, I wish to be bound only by the hereunto appended claims.