Patent · US Expired

Cholesteryl carbonates and carbamates of azo dyes

US4134888A · kind A · utility

1Cited by
3References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 1977
Grant dateJan 16, 1979
Priority date
Expiry dateFeb 28, 1997

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K19/601
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Novel liquid crystal dyes of the formula ##STR1## wherein (CHOL--) is a cholesteryl radical, X can be 0 or NH, R.sub.1 can be H, --OH, methyl, fluoro or chloro; R.sub.2 can be --NO.sub.2, --CN, N-(alkyl).sub.2, --OCOOR, --OCOR, alkyl or alkoxy and R.sub.3 can be H, methyl, fluoro or chloro, can be added to known liquid crystal compositions to impart color to the mixtures and improved contrast to a liquid crystal electro-optic device containing such mixtures.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.