Title:
HARD SURFACE RINSE-COATING COMPOSITION AND METHOD
United States Patent 3852075
Abstract:
A composition for improving the efficiency of automatic carwash establishments by facilitating the drying of cars and for imparting a protective coating to hard surfaces such as the exterior of cars which comprises non-volatile mineral oil, amine functional polydimethylsiloxane (AFDS) and cationic emulsifier at critical levels and in critical proportions. A method for applying a protective coating to hard surfaces is also provided.
US Patent References:
Cleaning compositions
Terry - October 1960 - 2955047
AUTOMOBILE POLISH
Yates - April 1970 - 3508933
PROTECTIVE COATING FOR METAL SURFACES
Holbus - June 1970 - 3518099
PROTECTIVE POLISH
Atherton - December 1970 - 3551168
/3702769.html
Vaughn - November 1972 - 3702769
Cleaning compositions
Terry - October 1960 - 2955047
AUTOMOBILE POLISH
Yates - April 1970 - 3508933
PROTECTIVE COATING FOR METAL SURFACES
Holbus - June 1970 - 3518099
PROTECTIVE POLISH
Atherton - December 1970 - 3551168
/3702769.html
Vaughn - November 1972 - 3702769
Application Number:
05/407031
Publication Date:
12/03/1974
Filing Date:
10/16/1973
View Patent Images:
Export Citation:
Assignee:
The Procter & Gamble Company (Cincinnati, OH)
Primary Class:
Other Classes:
106/287.130, 106/287.110
International Classes:
C08K5/01; C09G1/16; C08K5/00; C09G1/00; C09K1/02; C09G1/14
Field of Search:
106/3,10,11,287SB
Primary Examiner:
Morris, Theodore
Attorney, Agent or Firm:
Filcik, Julius Witte Richard Witte Monte P. C. D.
Claims:
What is claimed is
1. An aqueous rinse-coating composition which consisting essentially of:
2. The composition of claim 1 wherein there is additionally present from 1-10 percent by weight ethylene glycol.
3. The composition of claim 1 wherein said non-volatile mineral oil has a boiling point of at least 300°C. and said cationic emulsifier is selected from the group consisting of:
4. The composition of claim 3 wherein said non-volatile mineral oil is mineral seal oil and said cationic emulsifier is a mixture of dimethyl dicoco ammonium chloride, tallow trimethyl ammonium chloride and the condensation product of coconut amine with 2-5 moles of ethylene oxide per mole of amine.
5. The composition of claim 4 wherein there is additionally present from 1-10 percent by weight ethylene glycol.
6. The composition of claim 5 wherein said dimethyl dicoco ammonium chloride, tallow trimethyl ammonium chloride and condensation product of coconut amine with 2-5 moles ethylene oxide per mole of amine are present in the weight ratios of 1:0.35:0.27.
7. The composition of claim 6 wherein said mineral seal oil is present at 2.1 percent by weight, said amine functional polydimethylsiloxane is present at 5.2 percent by weight, said cationic emulsifier is present at 2.4 percent by weight, and said ethylene glycol is present at 5 percent by weight.
8. The composition of claim 7 wherein said amine functional polydimethylsiloxane is the reaction product of a hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 c.s. and a silane having the formula
9. An aqueous rinse-coating composition which consisting essentially of:
10. The composition of claim 9 wherein said non-volatile mineral oil is present at from 0.011 to 0.082 percent by weight, said amine functional polydimethylsiloxane is present at from 0.035-0.019 percent by weight and said cationic emulsifier is present at from 0.014-0.093 percent by weight.
11. The composition of claim 9 wherein said non-volatile mineral oil is present at from 0.026-0.049 percent by weight, said amine functional polydimethylsiloxane is present at from 0.076-0.115 percent by weight and said cationic emulsifier is present at from 0.032-0.056 percent by weight.
12. A method for applying a protective coating to hard surfaces which comprises contacting the surfaces to be protected with an aqueous solution consisting essentially of:
13. The method of claim 12 wherein said non-volatile mineral oil is present at from 0.011 to 0.082 percent by weight, said amine functional polydimethylsiloxane is present at from 0.035-0.019 percent by weight and said cationic emulsifier is present at from 0.014-0.093 percent by weight.
14. The method of claim 12 wherein said non-volatile mineral oil is present at from 0.026-0.049 percent by weight, said amine functional polydimethylsiloxane is present at from 0.076-0.115 percent by weight and said cationic emulsifier is present at from 0.032-0.056 percent by weight.
1. An aqueous rinse-coating composition which consisting essentially of:
2. The composition of claim 1 wherein there is additionally present from 1-10 percent by weight ethylene glycol.
3. The composition of claim 1 wherein said non-volatile mineral oil has a boiling point of at least 300°C. and said cationic emulsifier is selected from the group consisting of:
4. The composition of claim 3 wherein said non-volatile mineral oil is mineral seal oil and said cationic emulsifier is a mixture of dimethyl dicoco ammonium chloride, tallow trimethyl ammonium chloride and the condensation product of coconut amine with 2-5 moles of ethylene oxide per mole of amine.
5. The composition of claim 4 wherein there is additionally present from 1-10 percent by weight ethylene glycol.
6. The composition of claim 5 wherein said dimethyl dicoco ammonium chloride, tallow trimethyl ammonium chloride and condensation product of coconut amine with 2-5 moles ethylene oxide per mole of amine are present in the weight ratios of 1:0.35:0.27.
7. The composition of claim 6 wherein said mineral seal oil is present at 2.1 percent by weight, said amine functional polydimethylsiloxane is present at 5.2 percent by weight, said cationic emulsifier is present at 2.4 percent by weight, and said ethylene glycol is present at 5 percent by weight.
8. The composition of claim 7 wherein said amine functional polydimethylsiloxane is the reaction product of a hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 c.s. and a silane having the formula
9. An aqueous rinse-coating composition which consisting essentially of:
10. The composition of claim 9 wherein said non-volatile mineral oil is present at from 0.011 to 0.082 percent by weight, said amine functional polydimethylsiloxane is present at from 0.035-0.019 percent by weight and said cationic emulsifier is present at from 0.014-0.093 percent by weight.
11. The composition of claim 9 wherein said non-volatile mineral oil is present at from 0.026-0.049 percent by weight, said amine functional polydimethylsiloxane is present at from 0.076-0.115 percent by weight and said cationic emulsifier is present at from 0.032-0.056 percent by weight.
12. A method for applying a protective coating to hard surfaces which comprises contacting the surfaces to be protected with an aqueous solution consisting essentially of:
13. The method of claim 12 wherein said non-volatile mineral oil is present at from 0.011 to 0.082 percent by weight, said amine functional polydimethylsiloxane is present at from 0.035-0.019 percent by weight and said cationic emulsifier is present at from 0.014-0.093 percent by weight.
14. The method of claim 12 wherein said non-volatile mineral oil is present at from 0.026-0.049 percent by weight, said amine functional polydimethylsiloxane is present at from 0.076-0.115 percent by weight and said cationic emulsifier is present at from 0.032-0.056 percent by weight.
Description:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to compositions of matter useful in applying a protective coating to hard surfaces from an aqueous solution.
2. Description of the Prior Art
In recent years, automatic carwash establishments have become familiar members of the mercantile community. These establishments provide valuable service to their customers by cleaning the exterior of their customers' cars much more quickly and economically than was possible when manual labor was commonly used. During the course of the cleaning operation, the car is sprayed with an aqueous solution of detergent and the exterior is scrubbed with automatic brushes to loosen adhering soil. The car is then rinsed to remove the loosened soil and excess detergent solution and is dried automatically. In the past, one of the most inefficient steps in this carwashing operation was the drying step. If the car is properly cleaned during the detergent wash, the surface is wetted by the rinse water which results in a spreading of the rinse water in a thin film over the entire surface of the car thereby causing the ultimate removal of this rinse water to be difficult.
In order to make the drying operation more efficient, rinse additive compositions were developed. These compositions, which are fully described in U.S. Pat. No. 3,222,213 issued Dec. 7, 1965 and U.S. Pat. No. 3,497,365 issued Feb. 24, 1970 comprise solutions of mineral oil and cationic surface active agent. The cationic surface active agent apparently emulsifies the mineral oil in the rinse water thereby allowing a small quantity of mineral oil to be spread uniformly over the surface of the car and allowing the mineral oil to be plated out on the car surface. This coating of mineral oil renders the surface of the car hydrophobic. Water remaining on the surface of the car after the rinse operation forms itself into small beads which can be easily removed from the surface of the car as by contacting the car with a stream of air. This mineral oil coating is non-durable in that a simple water wash, such as occurs when the car is subjected to a gentle rain, removes the mineral oil coating.
It has long been recognized that a durable wax coating is beneficial to cars. Workers in the field discovered that the addition of carnauba wax to common rinse additive compositions would make the coating applied to the car more durable and, at the same time, not interfere with the action of the rinse additive in promoting drying of the car. Such compositions are fully described in U.S. Pat. No. 3,518,099 issued June 30, 1970. The addition of carnauba wax to the standard mineral oil and cationic surfactant-containing rinse additives does introduce certain problems. First, the compositions are difficult to prepare in that the carrauba wax is so difficult to emulsify that it is generally necessary to heat the rinse additive composition at the point of addition of carnauba wax. Such heating is, of course, expensive. Once the carnauba wax has been added to the hot composition in the proper emulsified form, it has been found necessary to add volatile mineral spirits to the composition in order to retain the carnauba wax in solution. Even with the addition of expensive volatile mineral spirits to the composition, rinse additive compositions containing carnauba wax are notoriously unstable during storage.
Another problem arises when the carnauba wax-containing rinse additives are used in the carwash establishment. Diluting the rinse additive composition for use dilutes the cationic emulsifiers and volatile mineral spirits to such a point that they no longer emulsify the carnauba wax sufficiently to allow it to effectively cover the car. In order to properly apply the carnauba wax-containing rinse additive to the car, hot water must be used in the rinse step. The use of hot water to rinse cars not only increases the cost of operation of the carwash establishment, but also causes the volatile mineral spirits in to rinse additive to be evaporated with attendent discomfort to employees and customers.
While the coating obtained through the use of carnauba wax in rinse additives is more durable than that obtained with the standard rinse additive along, the coating will not last through more than one or two detergent washes. Filming of the car windshields also occurs. In addition, carnauba wax is well known as a buffable wax; some degree of buffing is necessary in order to impart a sheen to the surface of the car.
SUMMARY OF THE INVENTION
The present invention provides compositions of matter comprising non-volatile mineral oil, amine functional polydimethylsiloxane (AFDS) and cationic emulsifiers which are particularly suitable for use in the rinse operations of carwash establishments. A method for the use of these compositions is also provided.
It is an object of this invention to increase the efficiency of carwash establishments by providing a rinse-coating composition which, when applied during the rinsing operation of a carwash establishment, imparts to the surface of the cars being washed a hydrophobic protective coating which causes the rinse water on the surface of the cars to form into beads thereby facilitating the drying of the cars. It is a further object of the present invention to provide a rinse-coating composition which will impart to the surface of the cars to which it is applied a hydrophobic protective coating which is resistant to detergent removal.
It is a further object of this invention to provide a rinse-coating composition which may be prepared at room temperature and which is shelf stable without the use of volatile mineral spirits.
It is a further object of this invention to provide a rinse-coating composition which may be utilized by carwash establishments in unheated or heated water.
It is a further object of this invention to provide a rinse-coating composition which, when used in the rinse operation of a carwash establishment, will not cause filming of the windshields of the cars being washed.
It is a still further object of this invention to provide a rinse-coating composition which, when used in the rinse operation of an automatic carwash establishment, will provide a substantial sheen to the surface of the clean cars without requiring buffing.
It is a further object of this invention to provide a method of applying a protective coating to hard surfaces.
Other objects will become apparent from the detailed description of the invention.
DESCRIPTION OF THE INVENTION
The rinse-coating composition provided by this invention comprises an aqueous dispersion of the following materials: (All compositions in this specification are in weight percent unless otherwise noted):
Amine functional poly- dimethylsiloxane (AFDS) 4.2 - 6.3% Non-volatile mineral oil (NVMO) 1.45 - 2.7% Cationic emulsifier 1.75 - 3.1%
wherein the ratio of NVMO to AFDS is from 0.20 to 0.80.
As will be described hereinafter, various other materials may also be beneficially added to the composition.
The amine functional polydimethylsiloxane ingredient is the product of the reaction of a hydroxyl endblocked polydimethylsiloxane and a silane.
The polydimethylsiloxane has the general formula ##SPC1##
wherein X is selected from the group consisting of acetoxy, alkylamino, benzamido and butanonoxime. The m is selected so that the viscosity of the polydimethylsiloxane is in the range of 10 to 15,000 cs. at 25°C. Preferably, the viscosity is in the range of 20 to 1,000 cs.
The silane is selected from the group consisting of compounds having the general formulas
R n "(R'O) 3 -n Si(CH 2 ) 3 NHR'" and
R n "(R'O) 3 -n SiRNHCH 2 CH 2 NH 2
wherein n has a value of from 0-2, R is a divalent hydrocarbon radical free of aliphatic unsaturation and containing 3-4 carbon atoms, R' is an alkyl radical containing from 1-4 carbon atoms, R" is a monovalent hydrocarbon radical free of aliphatic unsaturation and containing from 1-6 carbon atoms, and R'" is a hydrogen atom or a methyl radical. Preferably, n is 0. R is preferably a divalent aliphatic propyl radical. R' is preferably a methyl radical. When an R" radical is present (i.e., when n does not equal 0) it is preferably methyl. R'" is preferably hydrogen.
The weight ratio of the siloxane to the silane is from about 1:1 to about 20:1. The reaction between the siloxane and the silane is best conducted in the liquid phase by cold blending. If desired, a suitable solvent can be used. The exact composition of the two reactants and the exact proportions of these two reactants can be readily selected by one skilled in the art so as to produce as a final product an amine functional polydimethylsiloxane which may be used in this invention.
One specific reaction mixture which will produce a product useful in this invention consists of a hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 cs. and a silane having the formula
(CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2
the weight ratio of the siloxane to the silane being about 2:1. The reaction product is prepared by cold blending the siloxane and the silane.
A preferred amine functional polydimethylsiloxane is available as a commercial product from the Dow Corning Company of Midland, Mich. under the designation Dow Corning EF-13574B Emulsion and is generally described in U.S. Pat. No. 3,508,933 issued Apr. 28, 1970.
Non-volatile mineral oils suitable for use in the present invention are the paraffinic and naphthenic mineral oils having a boiling point higher than that of kerosine. Mineral oils such as mineral seal oil and those with a boiling point of at least 300°C. are preferred for use in the instant invention.
The cationic emulsifiers suitable for use in the instant invention are selected from the group of compounds known in the art as cationic surfactants. Cationic surfactants ionize in water to provide a positively charged cation which comprises the hydrophobic, lipophilic end of the surfactant molecule. Cationic surfactants specifically contemplated for use in the rinse-coating composition include the following materials:
1. Quaternary ammonium salts of fatty amines having at least one alkyl substituent which contains from 6-24 carbon atoms. Specific salts include acetates, chlorides, bromides and sulfates. Examples of suitable compounds include dicoco dimethyl ammonium chloride, ditallow dimethyl ammonium chloride, dicoco diethyl ammonium sulfate, and n-alkyl trimethylammonium halides such as dodecyl trimethyl ammonium bromide, coconut trimethyl ammonium chloride, and tallow trimethyl ammonium chloride.
2. The condensation products of primary fatty amines containing from 6-24 carbon atoms with alkylene oxides such as ethylene oxide and propylene oxide. Specific compounds include tallow amine reacted with 2-15 moles of ethylene oxide per mole of amine, coconut amine reacted with 2-15 moles ethylene oxide per mole of amine, and tallow diamine reacted with 30-60 moles of ethylene oxide per mole of amine.
3. The reaction products of long chain fatty acids containing from 6-24 carbon atoms and alkylene polyamines or alkylolamines. Typical compounds of this class are 1-(2-aminoethyl)-2-heptadecenyl-2-imidazoline and 1-(2-hydroxyethyl)-2-heptadecenyl-2-imidazoline.
Preferred cationic surfactants for the instant composition include dimethyl dicoco ammonium chloride (DMCC), the condensation products of coconut amine with 2-5 moles of ethylene oxide per mole of amine and a mixture of these two materials in a weight ratio of DMCC to ethylene oxide condensate of about 1.5 to about 4.5. A highly preferred cationic emulsifier is a mixture of dimethyl dicoco ammonium chloride, tallow trimethyl chloride and the condensation product of coconut amine with 2-5 moles ethylene oxide per mole of amine wherein the weight ratios of the three materials are about 1.0:0.35:0.27.
The rinse-coating composition of the instant invention is generally provided in the form of a concentrated aqueous composition which is mixed with water in the carwash establishment before use in the rinsing operation. In order to insure that the concentrated composition is stable on shelf storage (i.e., that the ingredients of the composition do not separate one from the other during long term storage), the concentrations and ratios of the materials must be carefully regulated. The critical ranges of the materials which have been found necessary to provide a stable composition are as follows:
amine functional polydimethylsiloxane 4.2 - 6.3% non-volatile mineral oil 1.45 - 2.7% cationic emulsifier 1.75 - 3.1%
It is also critical that the weight ratio of non-volatile mineral oil (NVMO) to AFDS be carefully controlled to fall within the range of 0.20-0.80. The control of this ratio within the noted range is necessary not only for the maintenance of a stable composition, but also for the proper performance of the rinse-coating composition in carwash rinse operations.
To make the useful, concentrated rinse-coating composition of this invention, the three critical materials are added to water. The order of addition of the materials to the water is immaterial. The temperature at which the addition of the materials to water is accomplished is likewise immaterial, with ordinary room temperatures (approximately 20°C.) being satisfactory. While the concentrated rinse-coating composition just described may be applied directly to the car, the concentrated composition is commonly and preferably used as a stock solution in various stages of dilution such as by diluting it in cold or hot water at a ratio of about 1 part composition to about 2-10 parts water. Preferably, 1 part composition is diluted with about 4 parts water. The stock solution is then added to the mixing equipment associated with that portion of an automatic carwash establishment which performs the rinsing operation on the car wherein additional dilution in the ratio of about 10 parts water to one part stock solution occurs.
The above discussion has been concerned with the rinse-coating composition of this invention in concentrated form. It is to be understood that the invention also encompasses diluted concentrated rinse-coating compositions and dilute rinse-coating compositions which are ready for application to a car.
Dilute aqueous rinse-coating compositions comprise the three critical materials in the following concentrations:
AFDS 0.035 - 4.2% NVMO 0.011 - 1.45% Cationic Emulsifier 0.014 - 1.75%
A preferred range for dilute aqueous rinse-coating compositions is:
AFDS 0.035 - 0.19% NVMO 0.011 - 0.082% Cationic Emulsifier 0.014 - .093%
A highly preferred concentration range for dilute aqueous rinse-coating compositions is:
AFDS 0.076 - 0.115% NVMO 0.026 - 0.049% Cationic Emulsifier 0.032 - 0.056% In each case noted above, the weight ratio of NVMO to AFDS in the dilute rinse-coating composition falls within the range of 0.20 - 0.80.
In use, the immediately above-described dilute rinse-coating compositions are sprayed on the car during the rinse operation in an automatic carwash establishment. The resulting coating causes beading of rinse water droplets thereby facilitating drying of the car as by contacting the car with a stream of air and provides the car with detergent resistant and rain resistant protective coating.
The inclusion of the three essential materials in the rinse-coating composition does not foreclose the use of optional additional ingredients which do not interfere with the action of the rinse-coating composition.
Preferred optional ingredients include water-miscible solvents such as alcohols and glycols which retard freezing of the rinse-coating composition and impart freeze-thaw stability to the composition. A highly preferred optional ingredient is the water-miscible solvent ethylene glycol. This highly preferred optional ingredient can be added to the concentrated rinse-coating composition in amounts of up to 10 percent of the total composition, preferably in amounts of 4-6 percent. In dilute rinse-coating compositions, the optional, highly preferred, water-miscible solvent ethylene glycol can be present at from 0.008 to 10 percent. Preferably, it is present at from 0.008-0.18 percent. The highly preferred concentration of ethylene glycol in the dilute rinse-coating composition is 0.072-0.10 percent.
Examples of other optional ingredients include coloring materials and perfumes. The use of the latter material in products which do not contain volatile mineral spirits is particularly desirable in that the perfumes provide aesthetic characteristics to the product which the customers of automatic carwash establishments find uniquely pleasing.
The method of using this invention involves contacting the surface of a cleaned car with an aqueous rinse-coating composition which comprises:
AFDS 0.035 - 6.3% NVMO 0.011 - 2.7% Cationic Emulsifier 0.014 - 3.1%
A preferred method of using this invention involves contacting the surface of a cleaned car with an aqueous rinsecoating composition which comprises:
AFDS 0.035 - 0.19% NVMO 0.011 - 0.082% Cationic Emulsifier 0.014 - 0.093%
A highly preferred method of using this invention involves contacting the surface of a cleaned car with an aqueous rinse-coating composition which comprises:
AFDS 0.076 - 0.115% NVMO 0.026 - 0.049% Cationic Emulsifier 0.032 - 0.056%
In each method noted above, the weight of ratio of NVMO to AFDS in the rinse-coating composition falls within the range of 0.20-0.80.
This invention can be usefully described by means of the following examples. These examples are to be construed as illustrative of the invention and not as limiting.
EXAMPLE I
The following materials were mixed with water to give a concentrated rinse-coating composition which was stable on long-term storage and after freezing and thawing.
______________________________________ Mineral Seal Oil 2.08% AFDS * 5.25 Dimethyl Dicco Ammonium ) Chloride (DMCC) 1.50 ) Ethomeen C-12 ** 0.40 )Cationic )Emulsifier: Quaternary Ammonium )Total: 2.42% Chloride * 0.525 ) Ethylene glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ______________________________________ **Ethylene oxide condensation products of primary fatty amines marketed b Armour Industrial Chemical Company. * The AFDS is contained in a product sold under the designation of Dow Corning EF-13574B Emulsion by Dow Corning Corporation. This product contains, in addition to the AFDS as hereinbefore described, a quaternary ammonium chloride which is n-alkyl trimethyl ammonium chloride.
When mixed with cold water at a ratio of 1 part composition to 4 parts water, a dilute rinse-coating composition was obtained. This dilute composition, when sprayed on cars during the rinsing operation at an automatic carwash establishment, imparted to the surface of the cars a protective coating which caused the rinse water to form into beads thereby facilitating the drying of the car by means of a current of air. The coating also gave a sheen to the surface of the treated cars. Upon further testing, it was found that the coating on the cars' surfaces remained effective in providing water repellency (as evidenced by the beading of water sprayed on the cars) through more than seven subsequent detergent washings in automatic carwash establishments. (During these subsequent washings no additional rinse-coating composition was applied.)
EXAMPLE II ____________________________________________________________ ______________ Mineral Seal Oil 1.04% AFDS * 5.25 DMCC 0.75 ) Ethomeen C-12 0.20 )Cationic )Emulsifier: Quaternary Ammonium )Total: 1.48% Chloride * 0.525 ) Ethylene Glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ____________________________________________________________ ______________ *AFDS and quaternary ammonium chloride are contained in a product sold under the designation of Dow Corning EF-13574-B Emulsion by the Dow Corning Corporation.
This composition is stable on storage, but, after dilution at 1 part composition to 4 parts water, fails to provide a water repellent coating on the surface of cars during the rinse operation of an automatic carwash establishment. It should be noted that the ratio of mineral oil to AFDS is outside the critical range. This example demonstrates the importance of the mineral oil:AFDS ratio.
EXAMPLE III ______________________________________ Mineral Seal Oil 2.08% AFDS * 1.75 DMCC 1.5 ) Ethomeen C-12 0.4 )Cationic )Emulsifier: Quaternary Ammonium )Total: 2.07% Chloride * 0.175 ) Ethylene Glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ______________________________________ *AFDS and quaternary ammonium chloride are contained in a product sold under the designation of Dow Corning EF-13574B emulsion by the Dow Cornin Corporation
This composition was unstable on storage (i.e., the composition separates into more than one phase). It should be noted that the weight ratio of mineral oil:AFDS is outside the critical range.
EXAMPLE IV ______________________________________ Mineral Seal Oil 2.1% AFDS * 5.25 DMCC 2.4 Water q.s. 100 ______________________________________ *The AFDS of this example is the reaction product of the cold blending of hydroxyl enblocked polydimethylsiloxane having a viscosity of about 40 cs and a silane having the formula (CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2 the weight ratio of the siloxane to the silane being about 2:1.
The composition of Example IV is stable on long term storage and when diluted in water at a ratio of 1 part composition to about 2 to 10 parts water results in a product which is suitable for application during the rinse operation of an automatic carwash establishment. The diluted product imparts a protective coating to cars during rinsing so as to facilitate the drying of the rinsed cars. A detergent resistant protective coating on the surface of the cars is also obtained.
The mineral seal oil is replaced with mineral oil having a boiling point of 400°C. The major characteristics of the rinse-coating composition remain unchanged.
In the composition of Example IV, the dimethyl dicoco ammonium chloride is replaced in turn with ditallow dimethyl ammonium chloride, dicoco diethyl ammonium sulfate, dodecyl trimethyl ammonium bromide, coconut trimethyl ammonium chloride, tallow trimethyl ammonium chloride, the reaction product of tallow amine and 5 moles ethylene oxide per mole of amine, the reaction product of coconut amine and 5 moles ethylene oxide per mole of amine, the reaction of tallow diamine and 45 moles of ethylene oxide per mole of diamine, 1-(2-aminoethyl)-2-heptadecenyl-2-imidazoline, 1-(2-hydroxyethyl)-2-heptadecenyl-2-imidazoline, a mixture of dimethyl dicoco ammonium chloride and the reaction product of coconut amine with 2-5 moles ethylene oxide per mole of amine wherein the ratio of the dimethyl dicoco ammonium chloride to ethylene oxide condensate product is about 4:1, a mixture of dimethyl dicoco ammonium chloride and the condensation product of coconut amine and 2-5 moles ethylene oxide per mole of amine wherein the ratio of dimethyl dicoco ammonium chloride and the ethylene oxide condensation product is about 1.6, and a mixture of dimethyl dicoco ammonium chloride and tallow trimethyl ammonium chloride and the condensation product of coconut amine and 2-5 moles ethylene oxide per mole of amine wherein the weight ratios of the three materials are 1.0:0.35:0.27. Each variation of the composition of Example IV as hereinbefore mentioned is stable on shelf storage and, when mixed with water in a ratio of 1 part composition to about 4 parts water, results in a highly effective dilute rinse-coating composition for use during the rinsing operations of automatic carwash establishments. The same results are obtained when ethylene glycol in the amount of 5 percent of the total concentrated composition is added to each variation; in addition, freeze-thaw stability is imparted to the compositions.
EXAMPLE V ______________________________________ Mineral Seal Oil 0.049% AFDS * 0.115 DMCC 0.044 Ethomeen C-12 0.011 Ethylene Glycol 0.10 Water q.s. 100 ______________________________________ *The AFDS of this example is the reaction product of the cold blending of hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 cs. and a silane having the formula (CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2 the weight ratio of the siloxane to the silane being about 2:1.
The dilute rinse-coating composition of Example V is sprayed on a car that has gone through the detergent wash section of an automatic carwash establishment. The excess water on the surface of the car forms itself into beads and is easily removed from the surface of the car by a stream of air. The water repellent protective coating is resistant to at least seven detergent washes in an automatic carwash establishment.
The novel, useful, rinse-coating compositions of this invention have been described in detail above in terms of compositions useful in automatic carwash establishments. While these compositions will find their greatest utility in automatic carwash establishments, it is to be understood that the compositions have utility beyond such use. For example, the rinse-coating compositions can be supplied to consumers for use on household appliances such as refrigerators and washing machines, and for use on other household surfaces such as kitchen cabinets, bathroom walls and fixtures, and metal and plastic siding. In fact, the rinse-coating compositions of this invention may be used on any hard surface to which it is desirable to impart a protective coating.
1. Field of the Invention
This invention relates to compositions of matter useful in applying a protective coating to hard surfaces from an aqueous solution.
2. Description of the Prior Art
In recent years, automatic carwash establishments have become familiar members of the mercantile community. These establishments provide valuable service to their customers by cleaning the exterior of their customers' cars much more quickly and economically than was possible when manual labor was commonly used. During the course of the cleaning operation, the car is sprayed with an aqueous solution of detergent and the exterior is scrubbed with automatic brushes to loosen adhering soil. The car is then rinsed to remove the loosened soil and excess detergent solution and is dried automatically. In the past, one of the most inefficient steps in this carwashing operation was the drying step. If the car is properly cleaned during the detergent wash, the surface is wetted by the rinse water which results in a spreading of the rinse water in a thin film over the entire surface of the car thereby causing the ultimate removal of this rinse water to be difficult.
In order to make the drying operation more efficient, rinse additive compositions were developed. These compositions, which are fully described in U.S. Pat. No. 3,222,213 issued Dec. 7, 1965 and U.S. Pat. No. 3,497,365 issued Feb. 24, 1970 comprise solutions of mineral oil and cationic surface active agent. The cationic surface active agent apparently emulsifies the mineral oil in the rinse water thereby allowing a small quantity of mineral oil to be spread uniformly over the surface of the car and allowing the mineral oil to be plated out on the car surface. This coating of mineral oil renders the surface of the car hydrophobic. Water remaining on the surface of the car after the rinse operation forms itself into small beads which can be easily removed from the surface of the car as by contacting the car with a stream of air. This mineral oil coating is non-durable in that a simple water wash, such as occurs when the car is subjected to a gentle rain, removes the mineral oil coating.
It has long been recognized that a durable wax coating is beneficial to cars. Workers in the field discovered that the addition of carnauba wax to common rinse additive compositions would make the coating applied to the car more durable and, at the same time, not interfere with the action of the rinse additive in promoting drying of the car. Such compositions are fully described in U.S. Pat. No. 3,518,099 issued June 30, 1970. The addition of carnauba wax to the standard mineral oil and cationic surfactant-containing rinse additives does introduce certain problems. First, the compositions are difficult to prepare in that the carrauba wax is so difficult to emulsify that it is generally necessary to heat the rinse additive composition at the point of addition of carnauba wax. Such heating is, of course, expensive. Once the carnauba wax has been added to the hot composition in the proper emulsified form, it has been found necessary to add volatile mineral spirits to the composition in order to retain the carnauba wax in solution. Even with the addition of expensive volatile mineral spirits to the composition, rinse additive compositions containing carnauba wax are notoriously unstable during storage.
Another problem arises when the carnauba wax-containing rinse additives are used in the carwash establishment. Diluting the rinse additive composition for use dilutes the cationic emulsifiers and volatile mineral spirits to such a point that they no longer emulsify the carnauba wax sufficiently to allow it to effectively cover the car. In order to properly apply the carnauba wax-containing rinse additive to the car, hot water must be used in the rinse step. The use of hot water to rinse cars not only increases the cost of operation of the carwash establishment, but also causes the volatile mineral spirits in to rinse additive to be evaporated with attendent discomfort to employees and customers.
While the coating obtained through the use of carnauba wax in rinse additives is more durable than that obtained with the standard rinse additive along, the coating will not last through more than one or two detergent washes. Filming of the car windshields also occurs. In addition, carnauba wax is well known as a buffable wax; some degree of buffing is necessary in order to impart a sheen to the surface of the car.
SUMMARY OF THE INVENTION
The present invention provides compositions of matter comprising non-volatile mineral oil, amine functional polydimethylsiloxane (AFDS) and cationic emulsifiers which are particularly suitable for use in the rinse operations of carwash establishments. A method for the use of these compositions is also provided.
It is an object of this invention to increase the efficiency of carwash establishments by providing a rinse-coating composition which, when applied during the rinsing operation of a carwash establishment, imparts to the surface of the cars being washed a hydrophobic protective coating which causes the rinse water on the surface of the cars to form into beads thereby facilitating the drying of the cars. It is a further object of the present invention to provide a rinse-coating composition which will impart to the surface of the cars to which it is applied a hydrophobic protective coating which is resistant to detergent removal.
It is a further object of this invention to provide a rinse-coating composition which may be prepared at room temperature and which is shelf stable without the use of volatile mineral spirits.
It is a further object of this invention to provide a rinse-coating composition which may be utilized by carwash establishments in unheated or heated water.
It is a further object of this invention to provide a rinse-coating composition which, when used in the rinse operation of a carwash establishment, will not cause filming of the windshields of the cars being washed.
It is a still further object of this invention to provide a rinse-coating composition which, when used in the rinse operation of an automatic carwash establishment, will provide a substantial sheen to the surface of the clean cars without requiring buffing.
It is a further object of this invention to provide a method of applying a protective coating to hard surfaces.
Other objects will become apparent from the detailed description of the invention.
DESCRIPTION OF THE INVENTION
The rinse-coating composition provided by this invention comprises an aqueous dispersion of the following materials: (All compositions in this specification are in weight percent unless otherwise noted):
Amine functional poly- dimethylsiloxane (AFDS) 4.2 - 6.3% Non-volatile mineral oil (NVMO) 1.45 - 2.7% Cationic emulsifier 1.75 - 3.1%
wherein the ratio of NVMO to AFDS is from 0.20 to 0.80.
As will be described hereinafter, various other materials may also be beneficially added to the composition.
The amine functional polydimethylsiloxane ingredient is the product of the reaction of a hydroxyl endblocked polydimethylsiloxane and a silane.
The polydimethylsiloxane has the general formula ##SPC1##
wherein X is selected from the group consisting of acetoxy, alkylamino, benzamido and butanonoxime. The m is selected so that the viscosity of the polydimethylsiloxane is in the range of 10 to 15,000 cs. at 25°C. Preferably, the viscosity is in the range of 20 to 1,000 cs.
The silane is selected from the group consisting of compounds having the general formulas
R n "(R'O) 3 -n Si(CH 2 ) 3 NHR'" and
R n "(R'O) 3 -n SiRNHCH 2 CH 2 NH 2
wherein n has a value of from 0-2, R is a divalent hydrocarbon radical free of aliphatic unsaturation and containing 3-4 carbon atoms, R' is an alkyl radical containing from 1-4 carbon atoms, R" is a monovalent hydrocarbon radical free of aliphatic unsaturation and containing from 1-6 carbon atoms, and R'" is a hydrogen atom or a methyl radical. Preferably, n is 0. R is preferably a divalent aliphatic propyl radical. R' is preferably a methyl radical. When an R" radical is present (i.e., when n does not equal 0) it is preferably methyl. R'" is preferably hydrogen.
The weight ratio of the siloxane to the silane is from about 1:1 to about 20:1. The reaction between the siloxane and the silane is best conducted in the liquid phase by cold blending. If desired, a suitable solvent can be used. The exact composition of the two reactants and the exact proportions of these two reactants can be readily selected by one skilled in the art so as to produce as a final product an amine functional polydimethylsiloxane which may be used in this invention.
One specific reaction mixture which will produce a product useful in this invention consists of a hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 cs. and a silane having the formula
(CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2
the weight ratio of the siloxane to the silane being about 2:1. The reaction product is prepared by cold blending the siloxane and the silane.
A preferred amine functional polydimethylsiloxane is available as a commercial product from the Dow Corning Company of Midland, Mich. under the designation Dow Corning EF-13574B Emulsion and is generally described in U.S. Pat. No. 3,508,933 issued Apr. 28, 1970.
Non-volatile mineral oils suitable for use in the present invention are the paraffinic and naphthenic mineral oils having a boiling point higher than that of kerosine. Mineral oils such as mineral seal oil and those with a boiling point of at least 300°C. are preferred for use in the instant invention.
The cationic emulsifiers suitable for use in the instant invention are selected from the group of compounds known in the art as cationic surfactants. Cationic surfactants ionize in water to provide a positively charged cation which comprises the hydrophobic, lipophilic end of the surfactant molecule. Cationic surfactants specifically contemplated for use in the rinse-coating composition include the following materials:
1. Quaternary ammonium salts of fatty amines having at least one alkyl substituent which contains from 6-24 carbon atoms. Specific salts include acetates, chlorides, bromides and sulfates. Examples of suitable compounds include dicoco dimethyl ammonium chloride, ditallow dimethyl ammonium chloride, dicoco diethyl ammonium sulfate, and n-alkyl trimethylammonium halides such as dodecyl trimethyl ammonium bromide, coconut trimethyl ammonium chloride, and tallow trimethyl ammonium chloride.
2. The condensation products of primary fatty amines containing from 6-24 carbon atoms with alkylene oxides such as ethylene oxide and propylene oxide. Specific compounds include tallow amine reacted with 2-15 moles of ethylene oxide per mole of amine, coconut amine reacted with 2-15 moles ethylene oxide per mole of amine, and tallow diamine reacted with 30-60 moles of ethylene oxide per mole of amine.
3. The reaction products of long chain fatty acids containing from 6-24 carbon atoms and alkylene polyamines or alkylolamines. Typical compounds of this class are 1-(2-aminoethyl)-2-heptadecenyl-2-imidazoline and 1-(2-hydroxyethyl)-2-heptadecenyl-2-imidazoline.
Preferred cationic surfactants for the instant composition include dimethyl dicoco ammonium chloride (DMCC), the condensation products of coconut amine with 2-5 moles of ethylene oxide per mole of amine and a mixture of these two materials in a weight ratio of DMCC to ethylene oxide condensate of about 1.5 to about 4.5. A highly preferred cationic emulsifier is a mixture of dimethyl dicoco ammonium chloride, tallow trimethyl chloride and the condensation product of coconut amine with 2-5 moles ethylene oxide per mole of amine wherein the weight ratios of the three materials are about 1.0:0.35:0.27.
The rinse-coating composition of the instant invention is generally provided in the form of a concentrated aqueous composition which is mixed with water in the carwash establishment before use in the rinsing operation. In order to insure that the concentrated composition is stable on shelf storage (i.e., that the ingredients of the composition do not separate one from the other during long term storage), the concentrations and ratios of the materials must be carefully regulated. The critical ranges of the materials which have been found necessary to provide a stable composition are as follows:
amine functional polydimethylsiloxane 4.2 - 6.3% non-volatile mineral oil 1.45 - 2.7% cationic emulsifier 1.75 - 3.1%
It is also critical that the weight ratio of non-volatile mineral oil (NVMO) to AFDS be carefully controlled to fall within the range of 0.20-0.80. The control of this ratio within the noted range is necessary not only for the maintenance of a stable composition, but also for the proper performance of the rinse-coating composition in carwash rinse operations.
To make the useful, concentrated rinse-coating composition of this invention, the three critical materials are added to water. The order of addition of the materials to the water is immaterial. The temperature at which the addition of the materials to water is accomplished is likewise immaterial, with ordinary room temperatures (approximately 20°C.) being satisfactory. While the concentrated rinse-coating composition just described may be applied directly to the car, the concentrated composition is commonly and preferably used as a stock solution in various stages of dilution such as by diluting it in cold or hot water at a ratio of about 1 part composition to about 2-10 parts water. Preferably, 1 part composition is diluted with about 4 parts water. The stock solution is then added to the mixing equipment associated with that portion of an automatic carwash establishment which performs the rinsing operation on the car wherein additional dilution in the ratio of about 10 parts water to one part stock solution occurs.
The above discussion has been concerned with the rinse-coating composition of this invention in concentrated form. It is to be understood that the invention also encompasses diluted concentrated rinse-coating compositions and dilute rinse-coating compositions which are ready for application to a car.
Dilute aqueous rinse-coating compositions comprise the three critical materials in the following concentrations:
AFDS 0.035 - 4.2% NVMO 0.011 - 1.45% Cationic Emulsifier 0.014 - 1.75%
A preferred range for dilute aqueous rinse-coating compositions is:
AFDS 0.035 - 0.19% NVMO 0.011 - 0.082% Cationic Emulsifier 0.014 - .093%
A highly preferred concentration range for dilute aqueous rinse-coating compositions is:
AFDS 0.076 - 0.115% NVMO 0.026 - 0.049% Cationic Emulsifier 0.032 - 0.056% In each case noted above, the weight ratio of NVMO to AFDS in the dilute rinse-coating composition falls within the range of 0.20 - 0.80.
In use, the immediately above-described dilute rinse-coating compositions are sprayed on the car during the rinse operation in an automatic carwash establishment. The resulting coating causes beading of rinse water droplets thereby facilitating drying of the car as by contacting the car with a stream of air and provides the car with detergent resistant and rain resistant protective coating.
The inclusion of the three essential materials in the rinse-coating composition does not foreclose the use of optional additional ingredients which do not interfere with the action of the rinse-coating composition.
Preferred optional ingredients include water-miscible solvents such as alcohols and glycols which retard freezing of the rinse-coating composition and impart freeze-thaw stability to the composition. A highly preferred optional ingredient is the water-miscible solvent ethylene glycol. This highly preferred optional ingredient can be added to the concentrated rinse-coating composition in amounts of up to 10 percent of the total composition, preferably in amounts of 4-6 percent. In dilute rinse-coating compositions, the optional, highly preferred, water-miscible solvent ethylene glycol can be present at from 0.008 to 10 percent. Preferably, it is present at from 0.008-0.18 percent. The highly preferred concentration of ethylene glycol in the dilute rinse-coating composition is 0.072-0.10 percent.
Examples of other optional ingredients include coloring materials and perfumes. The use of the latter material in products which do not contain volatile mineral spirits is particularly desirable in that the perfumes provide aesthetic characteristics to the product which the customers of automatic carwash establishments find uniquely pleasing.
The method of using this invention involves contacting the surface of a cleaned car with an aqueous rinse-coating composition which comprises:
AFDS 0.035 - 6.3% NVMO 0.011 - 2.7% Cationic Emulsifier 0.014 - 3.1%
A preferred method of using this invention involves contacting the surface of a cleaned car with an aqueous rinsecoating composition which comprises:
AFDS 0.035 - 0.19% NVMO 0.011 - 0.082% Cationic Emulsifier 0.014 - 0.093%
A highly preferred method of using this invention involves contacting the surface of a cleaned car with an aqueous rinse-coating composition which comprises:
AFDS 0.076 - 0.115% NVMO 0.026 - 0.049% Cationic Emulsifier 0.032 - 0.056%
In each method noted above, the weight of ratio of NVMO to AFDS in the rinse-coating composition falls within the range of 0.20-0.80.
This invention can be usefully described by means of the following examples. These examples are to be construed as illustrative of the invention and not as limiting.
EXAMPLE I
The following materials were mixed with water to give a concentrated rinse-coating composition which was stable on long-term storage and after freezing and thawing.
______________________________________ Mineral Seal Oil 2.08% AFDS * 5.25 Dimethyl Dicco Ammonium ) Chloride (DMCC) 1.50 ) Ethomeen C-12 ** 0.40 )Cationic )Emulsifier: Quaternary Ammonium )Total: 2.42% Chloride * 0.525 ) Ethylene glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ______________________________________ **Ethylene oxide condensation products of primary fatty amines marketed b Armour Industrial Chemical Company. * The AFDS is contained in a product sold under the designation of Dow Corning EF-13574B Emulsion by Dow Corning Corporation. This product contains, in addition to the AFDS as hereinbefore described, a quaternary ammonium chloride which is n-alkyl trimethyl ammonium chloride.
When mixed with cold water at a ratio of 1 part composition to 4 parts water, a dilute rinse-coating composition was obtained. This dilute composition, when sprayed on cars during the rinsing operation at an automatic carwash establishment, imparted to the surface of the cars a protective coating which caused the rinse water to form into beads thereby facilitating the drying of the car by means of a current of air. The coating also gave a sheen to the surface of the treated cars. Upon further testing, it was found that the coating on the cars' surfaces remained effective in providing water repellency (as evidenced by the beading of water sprayed on the cars) through more than seven subsequent detergent washings in automatic carwash establishments. (During these subsequent washings no additional rinse-coating composition was applied.)
EXAMPLE II ____________________________________________________________ ______________ Mineral Seal Oil 1.04% AFDS * 5.25 DMCC 0.75 ) Ethomeen C-12 0.20 )Cationic )Emulsifier: Quaternary Ammonium )Total: 1.48% Chloride * 0.525 ) Ethylene Glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ____________________________________________________________ ______________ *AFDS and quaternary ammonium chloride are contained in a product sold under the designation of Dow Corning EF-13574-B Emulsion by the Dow Corning Corporation.
This composition is stable on storage, but, after dilution at 1 part composition to 4 parts water, fails to provide a water repellent coating on the surface of cars during the rinse operation of an automatic carwash establishment. It should be noted that the ratio of mineral oil to AFDS is outside the critical range. This example demonstrates the importance of the mineral oil:AFDS ratio.
EXAMPLE III ______________________________________ Mineral Seal Oil 2.08% AFDS * 1.75 DMCC 1.5 ) Ethomeen C-12 0.4 )Cationic )Emulsifier: Quaternary Ammonium )Total: 2.07% Chloride * 0.175 ) Ethylene Glycol 5.0 Perfume 0.5 Color 0.05 Water q.s. 100 ______________________________________ *AFDS and quaternary ammonium chloride are contained in a product sold under the designation of Dow Corning EF-13574B emulsion by the Dow Cornin Corporation
This composition was unstable on storage (i.e., the composition separates into more than one phase). It should be noted that the weight ratio of mineral oil:AFDS is outside the critical range.
EXAMPLE IV ______________________________________ Mineral Seal Oil 2.1% AFDS * 5.25 DMCC 2.4 Water q.s. 100 ______________________________________ *The AFDS of this example is the reaction product of the cold blending of hydroxyl enblocked polydimethylsiloxane having a viscosity of about 40 cs and a silane having the formula (CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2 the weight ratio of the siloxane to the silane being about 2:1.
The composition of Example IV is stable on long term storage and when diluted in water at a ratio of 1 part composition to about 2 to 10 parts water results in a product which is suitable for application during the rinse operation of an automatic carwash establishment. The diluted product imparts a protective coating to cars during rinsing so as to facilitate the drying of the rinsed cars. A detergent resistant protective coating on the surface of the cars is also obtained.
The mineral seal oil is replaced with mineral oil having a boiling point of 400°C. The major characteristics of the rinse-coating composition remain unchanged.
In the composition of Example IV, the dimethyl dicoco ammonium chloride is replaced in turn with ditallow dimethyl ammonium chloride, dicoco diethyl ammonium sulfate, dodecyl trimethyl ammonium bromide, coconut trimethyl ammonium chloride, tallow trimethyl ammonium chloride, the reaction product of tallow amine and 5 moles ethylene oxide per mole of amine, the reaction product of coconut amine and 5 moles ethylene oxide per mole of amine, the reaction of tallow diamine and 45 moles of ethylene oxide per mole of diamine, 1-(2-aminoethyl)-2-heptadecenyl-2-imidazoline, 1-(2-hydroxyethyl)-2-heptadecenyl-2-imidazoline, a mixture of dimethyl dicoco ammonium chloride and the reaction product of coconut amine with 2-5 moles ethylene oxide per mole of amine wherein the ratio of the dimethyl dicoco ammonium chloride to ethylene oxide condensate product is about 4:1, a mixture of dimethyl dicoco ammonium chloride and the condensation product of coconut amine and 2-5 moles ethylene oxide per mole of amine wherein the ratio of dimethyl dicoco ammonium chloride and the ethylene oxide condensation product is about 1.6, and a mixture of dimethyl dicoco ammonium chloride and tallow trimethyl ammonium chloride and the condensation product of coconut amine and 2-5 moles ethylene oxide per mole of amine wherein the weight ratios of the three materials are 1.0:0.35:0.27. Each variation of the composition of Example IV as hereinbefore mentioned is stable on shelf storage and, when mixed with water in a ratio of 1 part composition to about 4 parts water, results in a highly effective dilute rinse-coating composition for use during the rinsing operations of automatic carwash establishments. The same results are obtained when ethylene glycol in the amount of 5 percent of the total concentrated composition is added to each variation; in addition, freeze-thaw stability is imparted to the compositions.
EXAMPLE V ______________________________________ Mineral Seal Oil 0.049% AFDS * 0.115 DMCC 0.044 Ethomeen C-12 0.011 Ethylene Glycol 0.10 Water q.s. 100 ______________________________________ *The AFDS of this example is the reaction product of the cold blending of hydroxyl endblocked polydimethylsiloxane having a viscosity of about 40 cs. and a silane having the formula (CH 3 O) 3 Si(CH 2 ) 3 NHCH 2 CH 2 NH 2 the weight ratio of the siloxane to the silane being about 2:1.
The dilute rinse-coating composition of Example V is sprayed on a car that has gone through the detergent wash section of an automatic carwash establishment. The excess water on the surface of the car forms itself into beads and is easily removed from the surface of the car by a stream of air. The water repellent protective coating is resistant to at least seven detergent washes in an automatic carwash establishment.
The novel, useful, rinse-coating compositions of this invention have been described in detail above in terms of compositions useful in automatic carwash establishments. While these compositions will find their greatest utility in automatic carwash establishments, it is to be understood that the compositions have utility beyond such use. For example, the rinse-coating compositions can be supplied to consumers for use on household appliances such as refrigerators and washing machines, and for use on other household surfaces such as kitchen cabinets, bathroom walls and fixtures, and metal and plastic siding. In fact, the rinse-coating compositions of this invention may be used on any hard surface to which it is desirable to impart a protective coating.