Abstract: A hair treatment composition comprising (A) a keratin-reducing substance; and (B) a nonionic amphiphatic compound which contains at least one long-chain branched alkyl or alkenyl group per molecule, and which has an HLB of 2-12, the compound itself or a mixture of the compound and water maintaining a liquid crystal structure at a temperature ranging from 0.degree.-50.degree. C. The composition possesses excellent moisturizability, smoothness and softness, exhibits a remarkably high conditioning effect which is sustainable, and exhibits the effects of reducing damage to the hair and preventing the occurrence of split hairs, and imparting gloss to the hair.

Abstract: A curly hair-straightening composition is disclosed, which comprises: (A) from 1 to 20% by weight of one or more keratin-reducing substances selected from the group consisting of thioglycolic acid, thioglycolic acid derivatives, cysteine, N-acylcysteines, salts thereof, thioglyceryl alkyl ethers, mercaptoalkylamides, sulfites and hydrogensulfites; (B) one or more alcohols selected from the group consisting of monohydric alcohols having a straight-chain or branched alkyl group carrying 3 or 4 carbon atoms and dihydric or trihydric alcohols having a straight-chain or branched alkyl group having 4 to 6 carbon atoms; and (C) water; wherein the weight ratio of the component (B) to the component (C) is from 1:3 to 3:1. Further, a method for straightening curly hair by using this composition is also disclosed. The curly hair-straightening composition of the present invention can permanently and sufficiently straighten natural curly hair or frizzy hair without causing any damage on the hair.

Abstract: A hair treatment composition Which comprises (A) 3 to 10% by weight, calculated as cysteine, of cysteine or its salt, (B) a saccharide or a polyhydric alcohol which has 4 to 20 carbon atoms, has 3 or more hydroxyl groups in the molecule, and which has no aldehyde group or ketone group, with the proportion by weight, (B)/(A) being less than 3.