Color pigment based on chitosan

Abstract

Abstract PURPOSE:To obtain a color pigment having a stable color tone by treating chitosan with a specified naphthoquinone compound or anthraquinone compound. CONSTITUTION:A solution of a naphthoquinone compound of formula I (wherein R<1> and R<2> are each H, halogen, hydroxyl, lower alkyl or a sulfonate salt group or an anthraquinone compound of formula II in an organic solvent is added to a water bath, and chitosan is dispersed therein and treated at 60-90 deg.C for 30min to 2hr. An aqueous alkali of a concentration of 5-20wt.% is then dropped therein to deposit a color pigment.

Inventors

• 👤 Susumu Shimoyama
• 👤 下山　進
• 👤 Ujiyou Maeda
• 👤 前田　雨城
• 👤 Keiko Maeda
• 👤 景子 前田
• 👤 Hiroko Noda
• 👤 野田　裕子
• 👤 Kunio Kataoka
• 👤 片岡　邦雄
• 👤 Eiichi Eto
• 👤 江藤　栄一
• 👤 Satoru Shimoyama
• 👤 下山　覚
• 👤 Yu Shimoyama
• 👤 佑 下山

Bibliographic Details