Patent · US Expired

Thermochromic esters

US5130049A · kind A · utility

1Cited by
5References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 19, 1989
Grant dateJul 14, 1992
Priority date
Expiry dateJun 19, 2009

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K19/3068
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

The invention relates to liquid crystalline compounds of the Formula I ##STR1## wherein R.sup.1, R.sup.2, X.sup.1, X.sup.2, m, and n are as defined herein. Preferably, the group R.sup.2 of the liquid crystalline compounds of Formula I is a chiral residue of the formula II ##STR2## wherein Q denotes an alkylene residue with up to 7 C atoms wherein one CH.sub.2 group may be replaced by --O--, --CO--O--, or --O--CO--, or a single bond; and PA0 Y denotes an alkyl residue with 2 to 7 C atoms wherein one CH.sub.2 group may be replaced by --O--, --CO--O--, or --O--CO--. The invention further relates to liquid crystal phases containing compounds of the Formula I, to electro-optic and thermographic devices, and to a method of surface thermography.

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