GB780553A - A method of coating glass - Google Patents

Abstract

Glass fabric is treated with an aqueous solution of a siloxane of the average general formula <FORM:0780553/IV (b)/1> in which R is a divalent or trivalent saturated aliphatic or cycloaliphatic hydrocarbon radical containing at least 3 carbon atoms, wherein each carboxyl group is attached to at least the third carbon atom from the silicon atom, R1 is a monovalent hydrocarbon or halogenated monovalent hydrocarbon radical free from aliphatic unsaturation, a is 1 or 2 and b has a value of from 0 to 1 inclusive, said solution having a pH of at least 8, and the fabric is then dried. The preferred siloxane is <FORM:0780553/IV (b)/2> though the R group may be propylene, tetramethylene, octadecamethylene, <FORM:0780553/IV (b)/3> cyclohexylene, cyclopentylene, methylcyclohexylene, 2:7-decahydro-naphthylene, <FORM:0780553/IV (b)/4> The R1 group may be alkyl, cycloalkyl, aryl, chlorophenyl, tribromoxenyl, a ,a ,a -trifluorotolyl, tetrafluoroethyl and chlorocyclohexyl. The acidic siloxanes may be neutralized by methylamine, ethanolamine, triethanolamine, ethylene diamine, ammonia, tetramethylammonium hydroxide or 2-hydroxyethyl-trimethylammonium hydroxide, and these may be subsequently removed by heating the treated glass fabric or by treating it with alkali metal hydroxides, carbonates or bicarbonates, the metallic ions being subsequently washed from the fabric. Acidic groups containing 8 or more carbon atoms ensure good lubrication, whereas those with less than 8 carbon atoms increase the strand integrity of the fabrics. The coatings cause increased adherence of resins such as polyesters, polyamides, phenol-formaldehydes, melamine-formaldehydes and urea-aldehydes to glass fabrics.ALSO:A glass surface is coated with an aqueous solution of a siloxane of the average general formula <FORM:0780553/III/1> in which R is a divalent or trivalent saturated aliphatic or cycloaliphatic hydrocarbon radical, containing at least 3 carbon atoms, wherein each carboxyl group is attached to at least the third carbon atom from the silicon atom, R1 is a monovalent hydrocarbon or halogenated monovalent hydrocarbon radical free from aliphatic unsaturation, a is 1 or 2 and b has a value of from 0 to 1 inclusive, said solution having a pH of at least 8, and the surface is then dried. The preferred siloxane is <FORM:0780553/III/2> though the R group may be propylene, tetramethylene, octadecamethylene, <FORM:0780553/III/3> cyclohexylene, cyclopentylene, methylcyclohexylene, 2 : 7 - decahydro-naphthylene, <FORM:0780553/III/4> and <FORM:0780553/III/5> The R1 group may be alkyl, cycloalkyl, aryl, chlorophenyl, tribromoxenyl, a ,a ,a -trifluorotolyl, tetrafluoroethyl and chlorocyclohexyl. The acidic siloxanes may be neutralized by methylamine, ethanolamine, triethanolamine, ethylene diamine, ammonia, tetramethylammonium hydroxide or 2-hydroxyethyl-trimethylammonium hydroxide and these subsequently removed by heating the treated glass, or by alkali metal hydroxides, carbonates or bicarbonates and the metallic ions subsequently washed from the glass. Acidic groups containing 8 or more carbon atoms ensure good lubrication. These coatings cause increased adherence of resins such as polyesters, polyamides, phenol - formaldehydes, melamine - formaldehyde and urea-aldehydes to glass.ALSO:A coating composition for glass surfaces comprises an aqueous solution of a siloxane of the average general formula <FORM:0780553/IV (a)/1> in which R is a divalent or trivalent saturated aliphatic or cycloaliphatic hydrocarbon radical, containing at least 3 carbon atoms, wherein each carboxyl group is attached to at least the third carbon atom from the silicon atom, R1 is a monovalent hydrocarbon or halogenated monovalent hydrocarbon radical free from aliphatic unsaturation, a is 1 or 2 and b has a value of from 0 to 1 inclusive, said solution having a pH of at least 8, and the surface is then dried. The preferred siloxane is <FORM:0780553/IV (a)/2> though the R group may be propylene, tetramethylene, octadecamethylene, <FORM:0780553/IV (a)/3> cyclohexylene, cyclopentylene, methylcyclohexylene, 2:7 - decahydro - naphthylene, <FORM:0780553/IV (a)/4> The R1 group may be alkyl, cycloalkyl, aryl, chlorophenyl, tribromoxenyl, a ,a ,a -trifluorotolyl, tetrafluoroethyl and chlorocyclohexyl. The acidic siloxanes may be neutralized by methylamine, ethanolamine, triethanolamine, ethylene diamine, ammonia, tetramethylammonium hydroxide or 2-hydroxyethyl-trimethylammonium hydroxide and these subsequently removed by heating the treated glass, or by alkali metal hydroxides, carbonates or bicarbonates and the metallic ions subsequently washed from the glass. Acidic groups containing 8 or more carbon atoms ensure good lubrication. These coatings cause increased adherence of resins such as polyesters, polyamides phenol-formaldehydes, melamine-formaldehyde and urea-aldehydes to glass.