US4490015A — Liquid crystal color display panel

Claim 1

Independent Claim 203 words

A liquid crystal color display panel including two transparent electrode-mounted substrates joined together with a gap therebetween, a displaying material composed of a system formed by dissolving optically active materials (chiral compounds) and dichroic dyes in nematic liquid crystals having negative dielectric anisotropy, the displaying material being enclosed in said gap for utilization of a change in the degree of light absorption of said displaying material upon application of a voltage across the electrodes, said display panel comprising one of said substrates being such that it has been given tilted perpendicular alignment preparation so as to allow liquid crystal and dichroic dye molecules to be tilt-aligned, in the vicinity of said one substrate, in a given direction at a tilt angle α meeting the relationship 0<α≦4° relative to a normal line to said one substrate, the other of said substrates being such that it has been given perpendicular alignment preparation so as to allow liquid crystal and dichroic dye molecules to be aligned, in the vicinity of said other substrate, without tilting from a normal line to said other substrate, said displaying material being such that the relationship between its thickness d as a material layer and its helical pitch p is d/p<1.

Claim 2

Dependent Claim 203 words

A liquid crystal color display panel including two transparent electrode-mounted substrates joined together with a gap therebetween, a displaying material composed of a system formed by dissolving optically active materials (chiral compounds) and dichroic dyes in nematic liquid crystals having negative dielectric anisotropy, the displaying material being enclosed in said gap for utilization of a change in the degree of light absorption of said displaying material upon application of a voltage across the electrodes, said display panel comprising one of said substrates being such that it has been given tilted perpendicular alignment preparation so as to allow liquid crystal and dichroic dye molecules to be tilt-aligned, in the vicinity of said one substrate, in a given direction at a tilt angle α meeting the relationship 0<α≦4° relative to a normal line to said one substrate, the other of said substrates being such that it has been given perpendicular alignment preparation so as to allow liquid crystal and dichroic dye molecules to be aligned, in the vicinity of said other substrate, without tilting from a normal line to said other substrate, said displaying material being such that the relationship between its thickness d as a material layer and its helical pitch p is d/p<1.

Claim 3

Dependent Claim 51 words

The liquid crystal color display panel as set forth in claim 1, wherein said substrate subjected to tilted perpendicular alignment preparation is such that its surface has been subjected to oblique vapor deposition of an oxide compound or fluoride compound and subsequently treated with a solution of a perpendicular orientation agent.

Claim 4

Dependent Claim 64 words

The liquid crystal color display panel as set forth in claim 1, wherein said substrate subjected to tilted perpendicular alignment preparation is such that it has a thin layer of an oxide compound, 500-5000 Å in thickness, formed on its surface, said layer having been subjected to rubbing with cloth in a given direction, then treated with a solution of a perpendicular orientation agent.

Claim 5

Dependent Claim 52 words

The liquid crystal color display panel as set forth in claim 1, wherein said substrate subjected to perpendicular alignment preparation is such that it has thin layer of an oxide compound, 500-5000 Å in thickness, formed on its surface, said layer having been treated with a solution of a perpendicular orientation agent.

Claim 6

Dependent Claim 55 words

The liquid crystal color display panel as set forth in claim 2, wherein said oxide compound is selected from the group consisting of SiO, SiO 2 , CeO 2 , and Al 2 O 3 , and said fluoride compound is selected from the group consisting of MgF 2 , CaF 2 , and LiF.

Claim 7

Dependent Claim 40 words

The liquid crystal color display panel as set forth in claim 3 or 4, wherein said oxide compound is selected from the group consisting of SiO 2 , TiO 2 , CeO 2 , and Al 2 O 3 .

Claim 8

Dependent Claim 49 words

The liquid crystal color display panel as set forth in claim 2, 3, or 4, wherein said perpendicular orientation agent is C 18 H 37 (CH 3 ) 2 ClN(CH 2 ) 3 Si(OCH 3 ) 3 or C 18 H 37 Si(OC 2 H 5 ) 3 .

Claim 9

Dependent Claim 36 words

The liquid crystal color display panel as set forth in claim 1, wherein said nematic liquid crystal having negative dielectric anisotropy is a mixed material containing at least one kind of dicyanohydroquinone derivative expressed as ##STR5##

Claim 10

Dependent Claim 21 words

The liquid crystal color display panel as set forth in claim 1, wherein said optically active material (chiral compound) is ##STR6##

Claim 11

Dependent Claim 29 words

The liquid crystal color display panel as set forth in claim 1, wherein said dichroic dyes are azo compounds ##STR7## anthraquinone compounds ##STR8## or a mixture of these compounds.

Claim 12

Dependent Claim 31 words

The liquid crystal color display panel as set forth in claim 1, wherein said relationship between the thickness d of said displaying material and the helical pitch p there is 0.2≦d/p≦0.8.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1987-12-25	1988-06-25	1988-12-25	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1991-12-25	1992-06-25	1992-12-25	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1995-12-25	1996-06-25	1996-12-25	$7700.00	Window Closed / Lapsed

Liquid crystal color display panel

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