Patent · US Expired

Ferroelectric liquid crystal mixtures containing lipohilizing, lipophilic or amphiphilic compounds for eliminating ionic impurities

US5333075A · kind A · utility

5Cited by

2References

6Claims

0Family size

Assignee

Hoechst GmbH · DE

Inventors

Takamasa Harada · Oberursel, DE
Claus Escher · Mühltal, DE
Gerd Illian · Tokyo, JP
Anke Kaltbeitzel
Norbert Rosch · Frankfurt am Main, DE

Key dates

Filing date	Apr 15, 1993
Grant date	Jul 26, 1994
Priority date	—
Expiry date	Apr 15, 2013

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC09K19/588
WIPO fieldBasic materials chemistry
WIPO sectorChemistry

Abstract

Electro-optical display devices having a cell thickness of 1 to 10 .mu.m, and containing ferroelectric liquid crystalline mixture, electrodes, alignment layer(s), in which the ferroelectric liquid crystalline mixture has a spontaneous polarization of Ps>20nC.cm.sup.-2 and a natural helical pitch of less than a half of the cell thickness, and contains lipophilizing, lipophilic or amphiphilic compounds for eliminating ionic impurities, Ferroelectric liquid crystal compositions according to the invention show a significantly reduced surface memory effect and an improved display contrast.

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