Preservatives for cosmetic, toiletry and pharmaceutical compositions
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.
1. A preservative composition blend comprising about 4.5% to about 15% caprylohydroxamic acid or a salt thereof, wherein caprylohydroxamic acid is the only hydroxamic acid in the composition blend, and about 7% to about 95.5% of a diol selected from the group consisting of 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.
2. The preservative composition blend according to claim 1 , wherein the composition is comprised of about 5% to about 15% caprylohydroxamic acid.
3. The preservative composition blend according to claim 1 , comprising about 30% to about 95% of the diol.
4. The preservative composition blend according to claim 1 , wherein the caprylhydroxamic acid is present in a concentration of about 5% to about 15% and comprising about 70% to about 95% of the diol.
5. The composition blend according to claim 4 , wherein the diol comprises a compound selected from the group consisting of caprylyl glyceryl ether, a propanediol, methylpropanediol, butylene glycol, 1,2-hexanediol, caprylyl glycol, glyceryl monocaprylate, ethylhexylglycerin, and a combination thereof.
6. The preservative composition blend according to claim 1 , wherein the caprylohydroxamic acid is synthesized from a natural fatty acid.
7. A formulation comprising the preservative composition blend of claim 1 and 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, preservatives, waxes, polymers and copolymers, inorganic and organic pigments, herbs, natural extracts, oils, pH adjusters, and combinations thereof.
8. The formulation of claim 7 , wherein the formulation has a pH of about 4 to about 8.
9. The formulation of claim 7 comprising the preservative composition blend of claim 1 in an amount of about 1.0% to about 2.0% of the formulation.
10. The formulation of claim 9 , wherein the formulation has a pH of about 6 to about 7.
11. The preservative composition blend according to claim 2 , further comprising an alcohol selected from the group consisting of phenoxyethanol, o-cymen-5-ol, and combinations thereof.
12. The preservative composition blend according to claim 11 further comprising a propylene carbonate.
13. A formulation comprising the preservative composition blend of claim 12 and 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, preservatives, waxes, polymers and copolymers, inorganic and organic pigments, herbs, natural extracts, oils, pH adjusters, and combinations thereof, wherein the formulation has a pH ranging from about 4 to about 8.
14. The formulation of claim 13 , wherein the formulation has a pH of about 4 to about 8.
15. The formulation of claim 13 comprising the preservative composition blend of claim 1 in an amount of about 1.0% to about 2.0% of the formulation.
16. The formulation of claim 15 , wherein the formulation has a pH of about 6 to about 7.