GB735303A - Improvements in or relating to methods of permanently waving human hair - Google Patents

Abstract

A process of permanently waving human hair comprises treating the hair with a solution of a reducing agent, allowing the solution to remain upon the hair in wound condition for a time sufficient to disrupt the disulphide linkages in the hair keratin and to soften the hair but insufficient to develop the wave fully, diluting the solution in situ to an extent sufficient to preclude further substantial chemical action and maintaining the hair with the diluted solution thereon in the wound form for a time sufficient to ensure substantial aerial oxidation of the hair and to develop the wave fully. Subsequent to the full development of the wave the hair may be treated with an oxidizing solution. The reducing solution may comprise ammonium thioglycollate, an amide of thioglycollic acid, b -mercapto-ethyl amine, b -hydroxyethylmercaptan, monomercapto-dimethyl ketone, b -monomercaptodiethyl ether, ethyl thioglycollate, mercaptoethanesulphonic acid, 3-mercapto - 2 - hydroxypropane - sulphonic acid, ammonium mercaptoethane sulphonate, cysteine hydrochloride, or ammonium N-(a -mercaptoacetyl)-p-aminosalicylate, and its pH may be adjusted to within 6.7 to 9.7 with ammonium hydroxide or a mixture of ammonium hydroxide with sodium hydroxide, ethanolamine or ethylene diamine. The solution may also include a perfume, a wetting agent, an agent serving to make the solution opaque, urea, ammonium sulphate or ammonium carbonate. The hair may be wound upon curlers, end-papers, or rods and, after the dilution step, may dry naturally or in a drier, and may remain in the wound condition for at least four hours while drying. The duration of the treatment with reducing solution may vary up to 30 minutes, depending upon the strength of the solution. Specification 723,917 is referred to.