The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 26, 1999
Filed:
Jun. 03, 1997
Kenji Takigawa, Nishio, JP;
Toshio Yamamoto, Kariya, JP;
Yuichiro Yamada, Nagoya, JP;
Yoshihiko Aihara, Yokohama, JP;
Shigeharu Hashimoto, Tokyo, JP;
Yoshiichi Suzuki, Tokyo, JP;
Denso Corporation, Kariya, JP;
Showa Shell Sekiyu Kabushiki Kaisha, Tokyo, JP;
Abstract
A liquid crystal cell which minimizes disordered orientation occurring with temperature changes even across a wide range, to exhibit good contrast and high reliability, as well as a smectic liquid crystal composition for use the liquid crystal cell are provided. In smectic liquid crystal compositions having a layer construction in the liquid crystal molecular arrangement, it was found that antiferroelectric liquid crystal compositions resistant to variation in the layer spacing of the smectic phase due to temperature changes are resistant to disordered orientation. Specifically, if the antiferroelectric liquid crystal composition contains at lest 45 wt % of an antiferroelectric liquid crystal compound with roughly constant layer spacing in a temperature range from the temperature t.sub.1 which gives the minimum value for the layer spacing of the smectic C.sub.A * phase to -20.degree. C., no disordered liquid crystal orientation results even after cold/hot temperature cycles. An even greater effect is achieved if the spontaneous polarization at of the composition at temperature t.sub.1 is at least 160 nC/cm.sup.2.