Optically anisotropic film

Details Optically anisotropic film Optically anisotropic film

1995-09-26

1998-03-24

Wu, Shean C.

Compositions

Liquid crystal compositions

349 96, 349 99, 349101, 349132, 349185, C09K 1952, G02F 1133

Patent

active

057308993

ABSTRACT:
An optically anisotropic film comprising a liquid crystal composition having twisted nematic alignment, characterized in that the helical axis of twisted nematic alignment is substantially parallel to the direction normal to the film plane, and the liquid crystal composition shows a cholesteric phase, contains at least one liquid crystal oligomer selected from the linear or cyclic liquid crystal oligomers (A) such as obtained from reaction of a vinyl monomer having a specific cholesterol group and pentamethylcyclopentasiloxane, and is defined by the fact that when the thickness of the film is represented by d (.mu.m) and the helical pitch of the twisted nematic phase is represented by P (.mu.m), d.gtoreq.3.times.P and P.ltoreq.0.3 .mu.m or P.gtoreq.0.8 .mu.m, wherein when the numbers of the recurring units (I) and (II) in one molecule of the liquid crystal oligomer (A) are supposed to be n and n', respectively, n and n' are each an integer of 1 to 20 and satisfy the relations of 4.ltoreq.n+n'.ltoreq.21 and n: n'=20:1 to 1:20, and the terminal group of the recurring unit (II) of the liquid crystal oligomer (A) is polymerized. This optically anisotropic film is capable of providing a liquid crystal display device with smaller viewing angle dependency of contrast or display color.

REFERENCES:
patent: 4358391 (1982-11-01), Finkelmann et al.
patent: 4410570 (1983-10-01), Kreuzer et al.
patent: 5210530 (1993-05-01), Heynderickx et al.
patent: 5211877 (1993-05-01), Andrejewski et al.
patent: 5250214 (1993-10-01), Kanemoto et al.
patent: 5326496 (1994-07-01), Iida et al.
Mol. Cryst Liq. Cryst, 1991, vol. 199, pp. 345-378.
SIS 1992 Digest, 401.
Brehmer et al., Macromol. Chem. Phys. 195, No. 6, 1891-1904 (1994).
Semmler et al., Polymers for Advanced Technologies, 5, 231-235 (1994).

Affiliated with

Also associated with

Rating

Optically anisotropic film does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Optically anisotropic film, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Optically anisotropic film will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2286277