Method for improving dichroism of azo dye for liquid crystal

Abstract

Abstract PURPOSE:To improve easily dichroism, by introducing a specified group such as a phenyl or cyclohexyl group into position 4 of a phenyl or naphthyl group situated at the terminal of the major molecular axis of an azo dye for liquid crystal. CONSTITUTION:At least one phenyl, cyclohexyl, phenylcarbonyloxy, or phenyloxycarbonyl group is introduced into position 4 of a phenyl of naphthyl group situated at the terminal of the major molecular axis of an azo dye for liquid crystal to obtain an azo dye having improved dichroism. Examples of the azo dyes for liquid crystal, which have improved dichroism are those of formulas I , II, III, etc. These dichroic azo dyes are used in a quantity of 0.01-20wt% based on that of host liquid crystal, whereby the quality of display using a guest-host system can be improved.

Inventors

• 👤 Shigeo Yasui
• 👤 茂男 安井
• 👤 Masashi Ono
• 👤 正志 小野
• 👤 Yoshiko Kobayashi
• 👤 小林　精子
• 👤 Shigeo Chitose
• 👤 千歳　重雄
• 👤 Tatsuo Uchida
• 👤 龍男 内田

Bibliographic Details