METHOD FOR STRAIGHTENING HUMAN HAIR FIBERS USING HEATING MEANS AND AN a-KETO ACID DERIVATIVE

Abstract

The invention concerns a method for straightening keratinous fibers including: (i) a step of applying on the keratinous fibers a hair straightening composition containing at least one alpha-hydroxy and/or keto acid derivative, the pH of said composition being not more than 9 (ii) a step of increasing the temperature of the keratinous fibers, using heating means, to a temperature ranging between 110 and 250° C.

1 - 14 . (canceled) 
     
     
         15 . A process for relaxing human hair fibers, comprising:
 applying to the hair fibers a hair-relaxing composition comprising at least one α-keto acid derivative, wherein the pH of the composition is less than or equal to 9, and   heating the hair fibers to a temperature ranging from 110° C. to 250° C.   
     
     
         16 . A process according to  claim 15 , wherein the hair fibers are heated to a temperature ranging from 120° C. to 220° C. 
     
     
         17 . A process according to  claim 16 , wherein the hair fibers are heated to a temperature ranging from 140° C. to 220° C. 
     
     
         18 . The process according to  claim 15 , wherein the composition is applied to wet hair fibers. 
     
     
         19 . The process according to  claim 15 , wherein the hair fibers are partially predried. 
     
     
         20 . The process accordin to  claim 15 , wherein the molar concentration of the at leat one α-keto acid derivative is from 2 to 8 M. 
     
     
         21 . The process according to  claim 20 , wherein the molar concentration of the at least one α-keto acid derivative is from 4 to 8 M. 
     
     
         22 . The process according to  claim 15 , wherein the pH of the composition is less than or equal to 7. 
     
     
         23 . The process according to  claim 15 , wherein the at least one a-keto acid derivative is chosen from compounds of formula (II): 
       
         
           
           
               
               
           
         
       
       wherein
 R 5  is chosen from:
 H, 
 COOH, 
 a linear or branched C 1 -C 6  alkyl optionally substituted with an OH, COOH, or Br radical; 
 a phenyl or benzyl optionally substituted with an OH or COOH radical; 
 or an indolyl radical or 
 
 
       
         
           
           
               
               
           
         
       
       and the stereoisomers and organic or mineral salts thereof. 
     
     
         24 . The process according to  claim 23 , wherein the compounds of formula (II) are chosen from:
 2-ketobutyric acid,   β-hydroxypyruvic acid,   3-methyl-2-oxobutyric acid,   2-oxovaleric acid,   ketomalonic acid,   3-methyl-2-oxovaleric acid,   trimethylpyruvic acid,   oxoacetic acid,   2-ketoglutaric acid,   benzylformic acid,   2-oxooctanoic acid,   2-oxoadipic acid,   phenylpyruvic acid,   bromopyruvic acid,   2-ketopimelic acid,   4-hydroxyphenylpyruvic acid,   3-indoleglyoxalic acid,   imidazolopyruvic acid HCl,   2-keto-L-gulonic acid,   2-carboxy-a-oxobenzeneacetic acid,   3-indolepyruvic acid,   2-ketoglutaric acid dihydrate,   pyruvamide,   N-methylpyruvamide,   N-ethylpyruvamide,   N,N-dimethylpyruvamide,   N-2-hydroxyethylpyruvamide,   and the stereoisomers and organic or mineral salts thereof.   
     
     
         25 . The process according to  claim 24 , wherein the compounds of formula (II) are chosen from:
 2-ketobutyric acid,   β-hydroxypyruvic acid,   ketomalonic acid,   oxoacetic acid,   2-ketoglutaric acid,   2-keto-L-gulonic acid,   2-ketoglutaric acid dihydrate, and   pyruvamide.   
     
     
         26 . A kit comprising at least:
 a heating apparatus that provides a temperature ranging from 110° C. to 250° C.,   at least one hair-relaxing composition comprising at least one α-keto acid derivative, wherein the pH of the at least one composition is less than or equal to 9.   
     
     
         27 . A kit according to  claim 26 , wherein the hair-relaxing composition comprises at least one α-keto acid chosen from:
 2-ketobutyric acid, 
 β-hydroxypyruvic acid, 
 3-methyl-2-oxobutyric acid, 
 2-oxovaleric acid, 
 ketomalonic acid, 
 3-methyl-2-oxovaleric acid, 
 trimethylpyruvic acid, 
 oxoacetic acid, 
 2-ketoglutaric acid, 
 benzylformic acid, 
 2-oxooctanoic acid, 
 2-oxoadipic acid, 
 phenylpyruvic acid, 
 bromopyruvic acid, 
 2-ketopimelic acid, 
 4-hydroxyphenylpyruvic acid, 
 3-indoleglyoxalic acid, 
 imidazolopyruvic acid HCl, 
 2-keto-L-gulconic acid, 
 2-carboxy-α-oxobenzeneacetic acid, 
 3-indolepyruvic acid, 
 2-ketoglutaric acid dihydrate, 
 pyruvamide, 
 N-methylpyruvamide, 
 N-ethylpyruvamide, 
 N,N-dimethylpyruvamide, 
 N-2-hydroxyethylpyruvamide, 
 
       and the stereoisomers and organic or mineral salts, or 
       mixtures thereof in all proportions.