Stock material or miscellaneous articles – Liquid crystal optical display having layer of specified...
Reexamination Certificate
1999-05-14
2002-07-09
Wu, Shean C. (Department: 1756)
Stock material or miscellaneous articles
Liquid crystal optical display having layer of specified...
C252S299630, C252S299660, C252S299670
Reexamination Certificate
active
06416825
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a liquid crystal composition and a liquid crystal display provided with the liquid crystal composition, and more particularly to a bistable liquid crystal composition which exhibits a cholesteric phase at room temperature and a liquid crystal display provided with the liquid crystal composition.
2. Description of Related Art
Recently, studies have been made to develop reflective type liquid crystal displays by using chiral nematic liquid crystal which is made by adding a chiral agent to nematic liquid crystal to exhibit a cholesteric phase at room temperature. Such a liquid crystal display makes a display by switching between a planar state and a focal conic state in accordance with the energy of a voltage applied thereto.
At present, however, such a reflective liquid crystal display which uses chiral nematic liquid crystal does not have good contrast between the planar state and the focal conic state, and liquid crystal displays of this type which are satisfactory in reflectivity, contrast and so on are yet to be developed.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a liquid crystal composition which is good in bistability, reflectivity and contrast and a liquid crystal display provided with the liquid crystal composition.
In order to attain the object, a liquid crystal composition according to the present invention comprises: a nematic liquid crystal material which contains a liquid crystal ester compound; and a chiral agent which mainly contains an ester compound with no cholesterol rings. A liquid crystal display according to the present invention comprises this liquid crystal composition between a pair of substrates, at least one of which is transparent.
The liquid crystal display according to the present invention, because it uses a liquid crystal ester compound, is improved in responsibility to a driving voltage, and especially improved in transparency, thereby resulting in a high contrast. Further, in prior art, the chiral agent added to the liquid crystal was an impurity which blocks the response to the driving voltage. According to the present invention, however, an ester compound which is similar to liquid crystal in structure is used as the main component of the chiral agent, which contributes to the improvement in reflective index characteristic and contrast.
REFERENCES:
patent: 4925592 (1990-05-01), Kano
patent: 5147577 (1992-09-01), Gray et al.
patent: 5156763 (1992-10-01), Gray et al.
patent: 5334327 (1994-08-01), Gray et al.
patent: 5387371 (1995-02-01), Pausch et al.
patent: 5478495 (1995-12-01), Terada et al.
patent: 5538768 (1996-07-01), Marden et al.
patent: 5611957 (1997-03-01), McDonnell et al.
patent: 5798058 (1998-08-01), Goodby et al.
patent: 5800737 (1998-09-01), Chan
patent: 5858271 (1999-01-01), Sekiguchi et al.
patent: 5861109 (1999-01-01), Goodby et al.
patent: 5955000 (1999-09-01), Carrick et al.
patent: 5980780 (1999-11-01), Motoyama et al.
patent: 6015507 (2000-01-01), Kobayashi et al.
patent: 6274208 (2001-08-01), Iwamatsu et al.
patent: 6287647 (2001-09-01), Kobayashi et al.
patent: 4-130412 (1992-05-01), None
patent: 5-224187 (1993-09-01), None
patent: 5-241119 (1993-09-01), None
Cowie et al., Polymer 37 (22), 1996.
Iwamatsu Masako
Kobayashi Nobuyuki
Ueda Hideaki
Minolta Co. , Ltd.
Sidley Austin Brown & Wood
Wu Shean C.
LandOfFree
Liquid crystal composition and liquid crystal display... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Liquid crystal composition and liquid crystal display..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Liquid crystal composition and liquid crystal display... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2897669