In:
Japanese Journal of Applied Physics, IOP Publishing, Vol. 37, No. 10R ( 1998-10-01), p. 5663-
Abstract:
We have investigated the thermal and optical stabilities of the
photoalignment layers for nematic liquid crystals (LCs). For the photoalignment layers, three kinds of photoisomerizable polymer
systems were studied; a polyamic acid doped with azobenzene molecules, a side-chain-substituted polyamic acid with azobenzene units, and a
main-chain-substituted polyamic acid with azobenzene units. Photoinduced anisotropy was produced by illumination with linearly polarized near-UV light
from a mercury lamp, and evaluated by measuring polarized UV absorption spectra and optical
birefringence. The nematic LC-alignment properties were investigated using the photoalignment layers processed under various thermal and optical conditions. It
was observed that the main-chain polyimide system exhibited good unidirectional LC alignment and excellent thermal (300°C for 1 h) and
optical stabilities. Moreover, we suggest a new procedure, in which the photoillumination process is carried out before the thermal imidization process,
to achieve a stable photoalignment layer.
Type of Medium:
Online Resource
ISSN:
0021-4922
,
1347-4065
DOI:
10.1143/JJAP.37.5663
Language:
Unknown
Publisher:
IOP Publishing
Publication Date:
1998
detail.hit.zdb_id:
218223-3
detail.hit.zdb_id:
797294-5
detail.hit.zdb_id:
2006801-3
detail.hit.zdb_id:
797295-7
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