Storage-stable compositions of glycerol monoalkyl ethers

Abstract

The present invention relates to compositions which comprise a combination a) of one or more glycerol monoalkyl ether(s) of the general formula R—O—CH 2 —CHOH—CH 2 OH in which R is a branched or unbranched C3-C18-alkyl group, where the alkyl group can be substituted by one or more hydroxyl and/or C1-C4-alkoxy group(s) and/or the alkyl chain can be interrupted by up to four oxygen atoms, with b) an antioxidant or two or more antioxidants as stabilizer(s), the simultaneous presence of phosphocholines and phosphocholine derivatives being excluded.

1 . A method to improve the long-term stabilization of a cosmetic or pharmaceutical composition, comprising adding to said cosmetic or pharmaceutical composition, a concentrate comprising from 95 to 99.999% by weight 3-[(2-ethylhexyl)oxy]-1,2-propanediol and an antioxidant in a weight ratio 3-[(2-ethylhexyl)oxy]-1,2-propanediol/antioxidant is in the range from 5,000:1 to 500:1 wherein said antioxidant is selected from the group consisting of Vitamin E, 3-tert-butyl-4-hydroxyanisole (BHA) and 2,6-tert-butyl-p-cresol (BHT) and mixtures thereof, such that said cosmetic or pharmaceutical composition is provided with 0.05% to 5% by weight of 3-[(2-ethylhexyl)oxy]-1,2-propanediol, and wherein a simultaneous presence of phosphocholine derivatives is excluded in said cosmetic or pharmaceutical composition. 
     
     
         2 . The method according to  claim 1 , wherein said oxidant is Vitamin E. 
     
     
         3 . The method according to  claim 1 , wherein said concentrate comprises from 99% to 99.99% by weight 3-[(2-ethylhexyl)oxy]-1,2-propanediol. 
     
     
         4 . The method according to  claim 1 , wherein said cosmetic or pharmaceutical composition is provided with 0.1% to 1% by weight of 3-[(2-ethylhexyl)oxy]-1,2-propanediol. 
     
     
         5 . The method according to  claim 1 , wherein said concentrate consists of from 95 to 99.999% by weight 3-[(2-ethylhexyl)oxy]-1,2-propanediol and an antioxidant in a weight ratio 3-[(2-ethylhexyl)oxy]-1,2-propanediol/antioxidant is in the range from 5,000:1 to 500:1 wherein said antioxidant is selected from the group consisting of Vitamin E, 3-tert-butyl-4-hydroxyanisole (BHA) and 2,6-tert-butyl-p-cresol (BHT) and mixtures thereof. 
     
     
         6 . The method according to  claim 5 , wherein said oxidant is Vitamin E. 
     
     
         7 . The method according to  claim 5 , wherein the proportion of 3-[(2-ethylhexyl) oxy]-1,2-propanediol in said concentrate is from 99% to 99.99% by weight. 
     
     
         8 . The method according to  claim 5 , wherein the proportion of 3-[(2-ethylhexyl) oxy]-1,2-propanediol in said concentrate is from 99.5% to 99.95% by weight. 
     
     
         9 . The method according to  claim 5 , wherein said cosmetic or pharmaceutical composition is provided with 0.1% to 1% by weight of 3-[(2-ethylhexyl)oxy]-1,2-propanediol.