Shear stable aminosilicone emulsions

Abstract

Aqueous emulsions of amino modified siloxanes may be made shear stable by the addition of at least one hydroxy carboxylic acid to the emulsion.

We claim:  
     
         1 . A shear stable aminosilicone emulsion composition comprising: 
 a. water;    b. emulsifier    b. an amino polysiloxane; and    c. at least one hydroxy carboxylic acid.    
     
     
         2 . A composition according to  claim 1  wherein the siloxane has a viscosity of from about 1 to 20,000 centipoises measured at 25° C., an amine content ranging from about 0.01% to 3% and has no silanol groups.  
     
     
         3 . A composition according to  claim 2  wherein the siloxane is MD a D* b M wherein D is O 1/2 Si(CH 3 ) 2 O 1/2 ; wherein D* is O 1/2 Si(CH 3 )QO 1/2 ; and M is O 1/2 SiQ j (CH 3 ) 3−j ., a ranges in value from about 30 to 600, j=0 or 1; and b ranges in value from about 0 to 100, b+j>0 and a/(b+j) is 0.5 to 5, Q is a polyether, polyhydric, amine, epoxy, alkyl of C 2 -C 18 , or alkanol, but at least one Q is an amine, which amine may be of the formula, BN[B 1 O(C d H 2d O) e R] 2−z V z , each d is 2 to 4, each e is 0 to 15, z is 0 to 2, each V is a univalent group, B 1  is an alkylene divalent bridging group on which there may be hydroxyl substituents, and B is a divalent bridging group.  
     
     
         4 . A composition according to  claim 1  wherein the hydroxy carboxylic acid is selected from the group consisting of glycolic acid, lactic acid, β-hydroxybutyric acid, and hydroxybenzoic acid.  
     
     
         5 . A composition according to  claim 1  wherein the amino polysiloxane has a polyether functionality.  
     
     
         6 . A composition according to  claim 1  wherein the emulsifier consists essentially of one or more non-ionic surfactants.  
     
     
         7 . A composition according to  claim 1  wherein the emulsifier is selected from the group consisting of polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ester, polyalkylene glycol and polyalkylene glycol modified polysiloxanes.  
     
     
         8 . A process which comprises: 
 providing an aqueous emulsion comprising an emulsifier and an amino polysiloxane; and    adding a shear stabilizing effective amount of at least one hydroxy carboxylic acid to the emulsion to impart shear stability to the emulsion.    
     
     
         9 . The process of  claim 8  wherein the amino polysiloxane corresponds to the formula MD a D* b M wherein D is O 1/2 Si(CH 3 ) 2 O 1/2 ; wherein D* is O 1/2 Si(CH 3 )QO 1/2 ; and M is O 1/2 SiQ j (CH 3 ) 3−j , a ranges in value from about 30 to 600, j=0 or 1; and b ranges in value from about 0 to 100, b+j>0 and a/(b+j) is 0.5 to 5, Q is a polyether, polyhydric, amine, epoxy, alkyl of C 2 -C 18 , or alkanol, but at least one Q is an amine, which amine may be of the formula, BN[B 1 O(C d H 2d O) e R] 2−z V z , d is 2 to 4, e is 0 to 15, z is 0 to 2, V is a univalent group, B 1  is an alkylene divalent bridging group on which there may be hydroxyl substituents, and B is a divalent bridging group.  
     
     
         10 . A process according to  claim 8  additionally comprising applying the shear stabilized emulsion to a substrate.  
     
     
         11 . A process according to  claim 10  wherein the substrate is a cellulosic fabric.  
     
     
         12 . A process according to  claim 8  wherein the hydroxy carboxylic acid is selected from the group consisting of glycolic acid, lactic acid, β-hydroxybutyric acid, and hydroxybenzoic acid.  
     
     
         13 . A process according to  claim 8  wherein the amino polysiloxane has polyether functionality.  
     
     
         14 . A process according to  claim 8  wherein the emulsifier consists essentially of one or more non-ionic surfactants.  
     
     
         15 . A process according to  claim 8  wherein the emulsifier is selected from the group consisting of polyoxyethylene alkyl ether, polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ester, polyalkylene glycol and polyalkylene glycol modified polysiloxanes.  
     
     
         16 . A process according to  claim 8  wherein the hydroxy carboxylic acid is glycolic acid.