Showa Denko K.k.

Hidemasa Aoki

Akira Shibuya

Makoto Saito

Motoaki Kamachi

Shinichi Yorozuya

Atsushi Tsuchiya

Akio Okamura

Akio Kuroiwa

Provided are hair processing agents capable of permanent waving hair even at a neutral to weakly acidic pH range that causes less irritation to the skin, and hair processing agents in which an unpleasant odor is masked. Hair processing agents contain at least one compound represented by the formula (2). Hair processing agents contain a compound of the formula (2) and at least one compound (ii) selected from thioglycolic acid, thiolactic acid, cysteine, acetylcysteine, cysteamine, acylcysteamine, salts thereof and ester derivatives thereof. Hair processing agents contain a compound of the formula (2), a surfactant and water, and are emulsified. Hair processing agents contain a compound of the formula (2) and a specific perfume. wherein X is a structure selected from &#x2014;O&#x2014;, &#x2014;S&#x2014;, &#x2014;NH&#x2014; and &#x2014;NR&#x2014;; Ris an alkyl group of 1 to 6 carbon atoms; Y is an oxygen atom or a sulfur atom; in the formula (1), Z is a divalent organic residue having at least one mercapto group; in the formula (2), R is a divalent organic residue optionally having a mercapto group; and Ris a hydrogen atom or an alkyl group of 1 to 6 carbon atoms. 

Hair processing agent and method for permanent waving hair

An object of the present invention is to provide a method for industrially producing &#x3b2;-mercapto carboxylic acids that are useful as synthetic raw materials for medicines and agrochemicals or as additives for polymer compounds from easily available &#x3b1;,&#x3b2;-unsaturated carboxylic acids in high yields and productivity. The present invention is characterized in that a solvent having an amide group and represented by the formula (1) is used when the &#x3b1;,&#x3b2;-unsaturated carboxylic acids are reacted with hydrogen sulfides to produce the &#x3b2;-mercapto carboxylic acids. Particularly, it is more preferable to carry out the reaction at a pH range of 6.0 to 8.5: (In the formula (1), Rrepresents any one of a hydrogen atom, an alkoxy group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms, an amino group, and an alkylamino group having 1 to 5 carbon atoms; Rand Reach represents independently any one of a hydrogen atom and an alkyl group having 1 to 5 carbon atoms; when both Rand Rare not a hydrogen atom, Rand Rmay together form a ring structure through an alkylene group; and when both Rand Rare not a hydrogen atom, Rand Rmay form a ring structure through an alkylene group).

Method for producing &#x3b2;-mercapto carboxylic acids

A method of the invention industrially produces heterocyclic mercapto compounds useful as raw materials or intermediates in the synthesis of medicaments or pesticides, or as permanent wave agent, with a high yield and high productivity using easily available starting materials. A heterocyclic mercapto compound represented by Formula (1) (wherein X represents any structure of &#x2014;O&#x2014;, &#x2014;S&#x2014;, &#x2014;NH&#x2014;, and &#x2014;NR&#x2014;; Rrepresents any of an alkyl group, alkoxy group and alkoxyalkyl group each having 1 to 6 carbon atoms; Y represents an oxygen atom, a sulfur atom or &#x2014;NR&#x2014;; Rrepresents a hydrogen atom or alkyl group having 1 to 6 carbon atoms; and Zrepresents a divalent organic residue having at least one mercapto group) is produced by reacting a metal sulfide or a metal hydrosulfide with a compound represented by Formula (2) (wherein X and Y are as defined in Formula (1); and Zrepresents a divalent organic residue having at least one halogen group) in the presence of a solvent at a pH of 7.0 to 11.0. 

Production method of heterocyclic mercapto compound

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Kawasaki, Japan

Hidemasa Aoki