Preservatives for Cosmetic, Toiletry and Pharmaceutical Compositions

Abstract

A composition for and methods of preserving a topical cosmetic, toiletry or pharmaceutical formulation against microbiological contamination or growth are described in which the compositions used herein include at least one hydroxamic acid, salt or complex thereof, and the methods include addition of an effective amount of such compounds to a cosmetic, toiletry or pharmaceutical formulation. Compositions further including alkanediols and/or solubilizing agents in blends with hydroxamic acid are also described.

I claim: 
     
         1 . A method of preserving a topical cosmetic, toiletry or pharmaceutical formulation against microbiological contamination or growth, comprising adding an effective amount of at least one hydroxamic acid, or a salt and/or a complex thereof. 
     
     
         2 . The method according to  claim 1 , wherein the at least one hydroxamic acid comprises an alkylhydroxamic acid. 
     
     
         3 . The method according to  claim 2 , wherein the alkylhydroxamic acid comprises a linear or branched, saturated or unsaturated, substituted or unsubstituted, carbon chain of two to about twenty-two carbon atoms. 
     
     
         4 . The method according to  claim 3 , wherein the alkylhydroxamic acid comprises a linear carbon chain of about six to about twelve carbon atoms. 
     
     
         5 . The method according to  claim 1 , wherein adding the at least one hydroxamic acid, or the salt and/or the complex thereof comprises adding precursors capable of reacting to form the at least one hydroxamic acid, salt and/or complex thereof as a reactant product. 
     
     
         6 . The method according to  claim 1 , wherein the at least one alkylhydroxamic acid is selected from the group consisting of hexanohydroxamic acid, caprylohydroxamic acid, caprohydroxamic acid, laurohydroxamic acid and mixtures and combinations thereof. 
     
     
         7 . The method according to  claim 6 , wherein the alkylhydroxamic acid is caprylohydroxamic acid. 
     
     
         8 . The method according to  claim 1 , further comprising at least one alcohol. 
     
     
         9 . The method according to  claim 8 , wherein the at least one alcohol is a diol. 
     
     
         10 . The method according to  claim 9 , wherein the at least one diol is a vicinal diol. 
     
     
         11 . The method according to  claim 10 , wherein the at least one vicinal diol is a 1,2-alkanediol. 
     
     
         12 . The method according to  claim 11 , wherein the at least one 1,2-alkanediol is selected from the group consisting of 1,2-pentanediol, 1,2-hexanediol. caprylyl glycol and mixtures and combinations thereof. 
     
     
         13 . The method according to  claim 10 , wherein the at least one vicinal diol is a glyceryl monoester and/or a glyceryl monoether. 
     
     
         14 . The method according to  claim 13 , wherein the at least one glyceryl monoester is selected from the group consisting of glyceryl monocaprate, glyceryl mono caproate, and glyceryl monocaprylate. 
     
     
         15 . The method according to  claim 13 , wherein the at least one glyceryl monoether is ethylhexyl glycerine. 
     
     
         16 . A composition useful for the preservation of topical cosmetic, toiletry and pharmaceutical formulations, wherein the composition is substantially free of parabens, comprising at least one hydroxamic acid, or a salt and/or a complex thereof and at least one alcohol. 
     
     
         17 . The composition according to  claim 16 , wherein the hydroxamic acid is an alkylhydroxamic acid comprising a linear or branched, saturated or unsaturated, substituted or unsubstituted, carbon chain of two to about twenty-two carbon atoms. 
     
     
         18 . The composition according to  claim 17 , wherein the alkylhydroxamic acid comprises a linear carbon chain of about six to about twelve carbon atoms. 
     
     
         19 . The composition according to  claim 16 , wherein the hydroxamic acid is an alkylhydroxamic acid selected from the group consisting of hexanohydroxamic acid, caprylohydroxamic acid, caprohydroxamic acid, laurohydroxamic acid and mixtures and combinations thereof. 
     
     
         20 . The composition according to  claim 19 , wherein the at least one alkylhydroxamic acid is caprylohydroxamic acid.