Patent GB-1005475-A (GB)
Title: Improvements in or relating to the treatment of leather
IPC: C14C9/02
Filed: 1964-01-20
Abstract: In fat-liquoring and waterproofing leather, e.g. chrome-tanned leather, it is fat-liquored, in an aqueous medium, with a water-soluble co-polymer prepared by mixing, e.g. in a solvent such as isopropyl, ethyl or methyl alcohol, (a) a silane having the general formula: <FORM:1005475/C6-C7/1> in which R is a divalent aliphatic hydrocarbon radical containing 3-6 carbon atoms, the Z2N. radical is attached to the third, fourth, fifth or sixth carbon atom from the silicon atom and contains not more than 10 carbon atoms, each Z is the same or different and is a hydrogen atom or a monovalent hydrocarbon radical, e.g. amino-substituted, R1 is an alkyl radical containing 1-7 carbon atoms, R11 is an alkyl radical containing 1-3 carbon atoms, e.g. .CH2.CH2.O.CH3 or .CH2.CH2.OH and n is zero or 1, and (b) a liquid hydroxylated polydimethylsiloxane having a viscosity of at least 30 cs. at 25 DEG  C., the weight ratio of (a) to (b) being between 1 : 1 and 1 : 20, e.g. 1 : 3. A monocarboxylic having 1-3 carbon atoms in its molecule, e.g. formic, acetic or propionic acid, may be included in the mixture.  The leather is then treated with a solution, in a non-aqueous solvent of a water-repellent composition, as described in Specifications 736,378 and 773,347, comprising (1) 15-50% by weight of a titanium compound Ti(OR111)4, or a zirconium compound Zr(OR111)4, or an aliphatic hydrocarbon-soluble partial hydrolysate of such Ti or Zr compound, in which compounds R111 is an aliphatic hydrocarbon radical containing less than 13 carbon atoms and less than 4, e.g. no, hydroxyl groups, (2) 5-70% by weight of a methylpolysiloxane composed essentially of trimethysiloxane units and SiO2 units and having a methyl to Si ratio between 1:1 and 1.5:1, and (3) 15-80% by weight of a polysiloxane having the average unit formula: <FORM:1005475/C6-C7/2> in which R111 is an alkyl or alkenyl radical containing less than 6 carbon atoms, or a monocyclic aryl radical, and average value of m is between 2 and 2.9.ALSO:In fat-liquoring and waterproofing leather, e.g. chrome-tanned leather, it is fat-liquored, in an aqueous medium, with a water-soluble copolymer prepared by mixing, e.g. in a solvent such as isopropyl, ethyl or methyl alcohol (a) a silane having the general formula <FORM:1005475/C3/1> in which R is a divalent aliphatic hydrocarbon radical containing 3 to 6 carbon atoms, the Z2N radical is attached to the third, fourth, fifth or sixth carbon atom from the silicon atom and contains not more than 10 carbon atoms, each Z is the same or different and is a hydrogen atom or a monovalent hydrocarbon or amino-substituted hydrocarbon radical, R1 is an alkyl radical containing 1 to 7 carbon atoms, R11 is an alkyl radical containing 1 to 3 carbon atoms, e.g. CH2.CH2.O.CH3 or CH2.CH2. OH and n is zero or 1, and (b) a liquid hydroxylated polydimethylsiloxane having a viscosity of at least 30 cs. at 25 DEG  C., the weight ratio of (a) to )b) being between 1 : 1 and 1 : 20, e.g. 1 : 3.  A monocarboxylic having 1 to 3 carbon atoms in its molecule, e.g. formic, acetic or propionic acid, may be included in the mixture. The leather is then treated with a solution, in a non-aqueous solvent, of a water-repellent composition, as described in Specifications 736,378 and 773,347, comprising (1) 15 to 50%, by weight, of a titanium compound Ti(OR111)4, or a zirconium compound Zr(OR111)4, or an aliphatic hydrocarbon-soluble partial hydrolysate of such Ti or Zr compound, in which compounds R111 is an aliphatic hydrocarbon radical containing less than 13 carbon atoms and less than 4, e.g. no, hydroxyl groups (2) 5 to 70% by weight, of a methylpolysiloxane composed essentially of trimethylsiloxane units and SiO2 units and having a methyl to Si ratio between 1 : 1 and 1.5 : 1, and (3) 15 to 80%, by weight, of a polysiloxane having the average unit formula <FORM:1005475/C3/2> in which R1111 is an alkyl or alkenyl radical containing less than 6 carbon atoms, or a monocyclic aryl radical, and the average value of m is between 2 and 2.9.ALSO:In fat-liquoring and waterproofing leather, e.g. chrometanned leather, it is fat-liquored, in an aqueous medium, with a water-soluble copolymer prepared by mixing, e.g. in a solvent such as isopropyl, ethyl or methyl alcohol, (a) a silane having the general formula: <FORM:1005475/D1-D2/1> in which R is a divalent apliphatic hydrocarbon radical containing 3 to 6 carbon atom, the Z2N, radical is attached to the third, fourth, fifth or sixth carbon atom from the silicon atom and contains carbon atom from the silicon atoms, each Z is the same or different and is a hydrogen atom or a monovalent hydrocarbon radical, e.g. amino-substituted, R1 is an alkyl radical containing 1 to 7 carbon atoms, R11 is an alkyl radical containing 1 to 3 carbon atoms, e.g. ,CH2,CH2,O,CH3 or ,CH2,CH2,OH and n i zero or 1, and (b) a liquid hydroxylated polydimethylsiloxane having a viscosity of at least 30 c. at 25\s2C., the weight ratio of (a) to (b) being between 1:1 and 1:20, e.g. 1:3. A monocarboxylic having 1 to 3 carbon atoms in its molecule, e.g. formic, acetic or propionic acid, may be included in the mixture.  The leather is then treated with a solution, in a non-aqueous solvent, of a water-repellent composition, as described in Specifications 736,378 and 773, 347, comprising (1) 15 to 50%, by weight, of a titanium compound Ti(OR111)4, or a zirconium compound Zr(OR1114, or an aliphatic hydrocarbon-soluble partial hydrolysate of such Ti or Zr compound, in which compounds R111 is an aliphatic hydrocarbon radical containing less than 13 carbon atoms and less than 4, e.g. no, hydroxyl groups (2) 5 to 70%, by weight, of a methylpolysilozane composed essentially of trimethylsiloxane units and SiO2 units and having a methyl to Si ratio between 1:1 and 1,5:1, and (3) 15 to 80%, by weight, of a polysiloxane having the average unit formula: R1111 <FORM:1005475/D1-D2/2> which R1111 is an alkyl or alkenyl radical containing less than 6 carbon atoms, or a monocylic aryl radical, and the average value of m is between 2 and 2,9.