Toyo Ink Manufacturing Company

Yoshimi Kikuchi

Shigeki Kato

Hitoshi Maki

Hitoshi Sugamo

Method of manufacturing a disazo pigment and disazo pigment manufactured

A process for producing 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester having a high purity from 1,4-cyclohexanedione-2,5-di(carboxylic acid alkyl ester) at high yields for a short period of time; a process for producing quinacridone of which the byproduct content is small, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester; and a process for producing quinacridone of which the particle diameter is adjusted as desired, from the above 2,5-di(arylamino)-3,6-dihydroterephthalic acid dialkyl ester without adding a step of forming a pigment.

Growing community of inventors

Tokyo, Japan

Yoshimi Kikuchi