Patent · US Expired

Quasi-liquid crystals

US4927917A · kind A · utility

2Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 19, 1988
Grant dateMay 22, 1990
Priority date
Expiry dateDec 19, 2008

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K19/3483
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

There are provided compounds which give quasi-liquid crystals, which comprise a mesogenic group, which can contain bridging groups, a bridging group and a spiropyran moiety having a 2H pyran ring, a terminal group being attached to the mesogenic group. The mesogenic group contains two aromatic, heterocyclic or cycloaliphatic ring structures. The compounds are prepared by a coupling reaction of mesogenic groups with a spiropyran compound via a suitable bridging group. There is provided a process for producing quasi-liquid crystalline (QLC) films which are useful for producing a wide variety of devices based on the optical non-linearity of generation of second harmonics by such films. Such devices can also be based on ferroelectric, pyroelectric, piezoelectric effects and photoactivity of such oriented QLC films.

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