Patent · US Expired

Certain photochromic fulgide compounds and method for their synthesis

US4803287A · kind A · utility

6Cited by
1References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 9, 1987
Grant dateFeb 7, 1989
Priority date
Expiry dateMar 9, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11B7/244
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

The invention provides a photochromic material characterized by an improvnt in balance of the substituents in the conventional furylfulgides and represented by the general formula: ##STR1## (wherein R represents an alkyl chain having 5 to 31 carbon atoms). According to this molecular structure, a mutually appropriate steric hindrance is induced between the isopropylidence group and the long-chain alkyl group to make the regio isomer unstable, thus preventing the regio isomer from being by-produced while also inhibiting any isomerization reaction from occuring in the synthesis of the fulgide. Further, a good balance of hydrophilic part and hydrophobic part is produced to facilitate formation of a Langmuir-Blodgett film.

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