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.

What is claimed is: 
     
         1 - 20 . (canceled) 
     
     
         21 . A preservative composition comprising:
 (i) about 4.5% to about 15% of a single alkylhydroxamic acid or a salt thereof selected from: caprohydroxamic acid or salts thereof, caprylohydroxamic acid or salts thereof, caprinohydroxamic acid or salts thereof, and laurohydroxamic acid or salts thereof;   (ii) about 7% to about 95.5% of a diol selected from: a C 3 -C 10  1,2-vicinal diol, a C 5  to C 10  glyceryl monoether, a C 5  to C 10  glyceryl monoester, and combinations thereof; and   (iii) about 1% to about 70% of a solubilizing agent,   wherein the preservative composition is free of parabens.   
     
     
         22 . The preservative composition of  claim 21 , wherein the solubilizing agent is selected from: a second diol, glycerin, and combinations thereof. 
     
     
         23 . The preservative composition of  claim 22 , wherein the single alkylhydroxamic acid or a salt thereof is present in a concentration of about 5% to about 15%. 
     
     
         24 . The preservative composition of  claim 23 , wherein the diol is present in a concentration of about 70% to about 95%. 
     
     
         25 . The preservative composition of  claim 24 , wherein the solubilizing agent is present in a concentration of about 15% to about 55%. 
     
     
         26 . The preservative composition of  claim 25 , wherein the diol is selected from: a propanediol, methylpropanediol, a butylene glycol, 1,2-pentanediol, 1,2-hexanediol, caprylyl glycol, 1,2-decanediol, caprylyl glyceryl ether, ethylhexylglycerin, glyceryl monolaurate, glyceryl monocaprate, glyceryl monocaprylate, and combinations thereof. 
     
     
         27 . The preservative composition of  claim 26 , wherein the single alkylhydroxamic acid or a salt thereof is caprylohydroxamic acid and salts thereof. 
     
     
         28 . A method of preserving a cosmetic, toiletry, or pharmaceutical formulation against microbiological contamination or growth, comprising adding an effective amount of the preservative composition of  claim 21  to the cosmetic, toiletry, or pharmaceutical formulation. 
     
     
         29 . The method of  claim 28 , wherein the cosmetic, toiletry, or pharmaceutical formulation is free of parabens. 
     
     
         30 . The method of  claim 29 , wherein the effective amount of the preservative composition prevents the microbiological contamination or growth of  Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans, Aspergillus niger , or a combination thereof. 
     
     
         31 . The method of  claim 29 , wherein the effective amount of the preservative composition maintains the concentration of  Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans , or  Aspergillus niger  present in the cosmetic, toiletry, or pharmaceutical formulation below 1.00 colony forming units per gram for a period of at least 28 days. 
     
     
         32 . A method for preventing microbiological contamination in a cosmetic, toiletry, or pharmaceutical formulation against, comprising adding an effective amount of a preservative composition to the cosmetic, toiletry, or pharmaceutical formulation,
 wherein the preservative composition comprises   (i) a single alkylhydroxamic acid or a salt thereof selected from: hexanohydroxamic acid or salts thereof, caprylohydroxamic acid or salts thereof, caprinohydroxamic caprohydroxamic acid or salts thereof, and laurohydroxamic acid or salts thereof; and   (ii) a diol selected from: a C 3 -C 10  1,2-vicinal diol, a C 5  to C 10  glyceryl monoether, a C 5  to C 10  glyceryl monoester, and combinations thereof,   wherein the effective amount of the preservative composition maintains the concentration of  Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans , or  Aspergillus niger  present in the cosmetic, toiletry, or pharmaceutical formulation below 1.00 colony forming units per gram for a period of at least 28 days.   
     
     
         33 . The method of  claim 32 , wherein the cosmetic, toiletry, or pharmaceutical formulation and preservative composition are free of parabens. 
     
     
         34 . The method of  claim 33 , wherein the preservative composition further comprises a solubilizing agent. 
     
     
         35 . The method of  claim 34 , wherein the single alkylhydroxamic acid is present in a concentration of about 4.5% to about 15%, the diol is present in a concentration of about 7% to about 95.5%, and the solubilizing agent is present in a concentration of about 1% to about 70%. 
     
     
         36 . The method of  claim 34 , wherein the diol is selected from: a propanediol, methylpropanediol, a butylene glycol, 1,2-pentanediol, 1,2-hexanediol, caprylyl glycol, 1,2-decanediol, caprylyl glyceryl ether, ethylhexylglycerin, glyceryl monolaurate, glyceryl monocaprate, glyceryl monocaprylate, and combinations thereof, and the solubilizing agent is selected from a diol, glycerin, or combinations thereof. 
     
     
         37 . The method of  claim 36 , wherein the single alkylhydroxamic acid is present in a concentration of about 5% to about 15%, the diol is present in a concentration of about 30% to about 95%, and the solubilizing agent is present in a concentration of about 15% to about 55%. 
     
     
         38 . A cosmetic, toiletry, or pharmaceutical formulation comprising an effective amount of the preservative composition of  claim 21 , wherein the effective amount of the preservative composition maintains the concentration of  Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Candida albicans , or  Aspergillus niger  present in the cosmetic, toiletry, or pharmaceutical formulation below 1.00 colony forming units per gram for a period of at least 28 days. 
     
     
         39 . The formulation of  claim 38 , further comprising one or more additives selected from the group consisting of water, colorants, fragrances, humectants, emulsifiers and/or thickeners, chelating agents, gelling agents, amino acids, emollients, solvents, sunscreen UVA and/or UVB blocking agents, antioxidants, additional preservatives, waxes, polymers and copolymers, inorganic and organic pigments, herbs, natural extracts, oils, pH adjusters, and combinations thereof. 
     
     
         40 . The formulation of  claim 38 , wherein the effective amount of the preservative composition of  claim 21  is about 1.0% to about 2.0% of the formulation.