Antiperspirant compositions

Abstract

A firm solid antiperspirant composition having a continuous phase comprising water-immiscible liquid containing i) one or more gelating structurant materials which form a network of fibres within the liquid, and ii) a polymeric thickener which has an organic polymer backbone containing at least five monomer repeat units, which polymer has the ability to increase the viscosity of the water-immiscible liquid in the absence of the gelating structurant materials; and iii) an antiperspirant active dispersed in the continuous phase, said composition being free from or containing less than 3% by weight of a fatty alcohol that is solid at 20° C.

We claim:  
     
         1 . A firm solid antiperspirant composition having a continuous phase comprising water-immiscible liquid containing: 
 i) one or more gelating structurant materials which form a network of fibres within the liquid, and    ii) a polymeric thickener which has an organic polymer backbone containing at least five monomer repeat units, which polymer has the ability to increase the viscosity of the water-immiscible liquid in the absence of the gelating structurant materials; and    iii) an antiperspirant active dispersed in the continuous phase said composition being free from or containing less than 3% by weight of a fatty alcohol that is solid at 20° C.    
     
     
         2 . A composition according to  claim 1  which does not contain more than 3% of any material which is solid at 30° C., is molten at 95° C., soluble in the water-immiscible liquid at 95° C., but does not form a network of fibres in the water-immiscible liquid.  
     
     
         3 . A composition according to  claim 1  wherein the total amount of said fibre-forming structurant (i) and said polymeric thickener (ii) is from 3% to 18% by weight of the composition.  
     
     
         4 . A composition according to  claim 3  wherein the total amount of said gelating structurant (i) and said polymeric thickener (ii) is from 4% to 16% by weight of the composition.  
     
     
         5 . A composition according to  claim 1  wherein the total amount of fibre-forming gelating structurant material is from 3% to 15% by weight of the composition.  
     
     
         6 . A composition according to any one of the preceding claims wherein the percentage of fibre-forming structurant is greater than the percentage of polymeric thickener by weight of the composition.  
     
     
         7 . A composition according to  claim 7  wherein the fibre forming structurant and polymeric are present in a weight ratio in the range of from 2:1 to 40:1.  
     
     
         8 . A composition according to  claim 1 ,  3   6  or  7  wherein the organic polymeric thickener comprises a polysaccharide esterified with a monocarboxylic acid of 8 to 22 carbon atoms.  
     
     
         9 . A composition according to  claim 8  containing from 0.5% to 5% by weight of the composition of a said esterified polysaccharide.  
     
     
         10 . A composition according to  claim 8  or  claim 9  wherein the esterified polysaccharide is a dextrin fatty acid ester having the formula  
       
         
           
           
               
               
           
         
       
       wherein each R group, individually, is a hydrogen or an acyl group of up to 22 carbon atoms, provided that at least one R group per glucose unit is an acyl group of 8 to 22 carbon atoms, and m has a value from about 20 to 30.  
     
     
         11 . A composition according to any one of claims  1 ,  3 ,  6  or  7  wherein the organic polymeric thickener comprises hydrogenated styrene-isoprene copolymer.  
     
     
         12 . A composition according to  claim 1  characterised in that the water-immiscible liquid contains a volatile silicone and optionally a non-volatile silicone and/or a non-silicone hydrophobic organic liquid selected from hydrocarbons, hydrophobic aliphatic esters, aromatic esters and hydrophobic alcohols.  
     
     
         13 . A composition according to  claim 1  wherein the water-immiscible liquid contains silicone oil in an amount which is at least 10% by weight of the composition.  
     
     
         14 . A composition according to  claim 1  wherein the composition is a suspension with a particulate solid material dispersed in said continuous phase.  
     
     
         15 . A composition according to  claim 1  wherein the composition is an emulsion with a hydrophilic, preferably water-miscible, disperse phase in addition to said water-immiscible liquid continuous phase.  
     
     
         16 . A composition according to  claim 15  wherein the disperse phase contains a diol or polyol.  
     
     
         17 . A composition according to  claim 15  which contains from 0.1% to 10% by weight of a nonionic emulsifier.  
     
     
         18 . A composition according to according to  claim 1  wherein the antiperspirant active comprises an aluminium and/or zirconium halohydrate, an activated aluminium and/or zirconium halohydrate, or an aluminium and/or zirconium complex or an activated aluminium and/or zirconium complex.  
     
     
         19 . A composition according to  claim 18  wherein the antiperspirant active comprises a halohydrate or complex in which aluminium and zirconium are both present.  
     
     
         20 . A composition according to  claim 1  wherein the proportion of antiperspirant active is from 5 to 40% by weight of the composition.  
     
     
         21 . An antiperspirant product comprising a dispensing container having an open end for extrusion of the contents of the container, means for urging the contents of the container towards the said open end, and a stick of composition according to  claim 1  accommodated within the container.  
     
     
         22 . A method of making a composition according to  claim 1  comprising: 
 mixing the ingredients of the composition and, before, during or after mixing, heating the ingredients of the composition to a temperature at which continuous phase is a mobile liquid in which the fibre-forming structurant material (i) and the organic polymer thickener (ii) are dissolved in the water-immiscible liquid,  
 introducing the composition, at a temperature at which it is mobile, into containers,  
 causing or allowing cooling of the containers, until the temperature of the composition in the containers has fallen below 30° C.  
 
     
     
         23 . A method according to  claim 22  wherein the step of mixing and heating the ingredients comprises mixing the fibre-forming structurant and the polymeric thickener with the water immiscible liquid and, before, during or after mixing, heating them to a temperature at which continuous phase is a mobile liquid in which the fibre-forming structurant material and the organic polymer thickener are dissolved in the water-immiscible liquid, then adding a solution of antiperspirant active.