US4391489A
Expired / Lapsed
US
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Liquid crystal materials containing pleochroic anthraquinone dyes
Assignee: Qinetiq Ltd
•
Filing: 1981-07-27
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Granted: 1983-07-05
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Expires: 2001-07-27
Abstract
Abstract A material suitable for a guest-host liquid crystal device comprises a solution of a liquid crystal material and a pleochroic dye wherein the pleochroic dye comprises at least one compound having a formula: ##STR1## wherein one of X and Y is OH and the other is NHR wherein R is H or lower alkyl; each of R 1 and R 2 independently represents alkyl, aryl, aralkyl, alkoxy or --NR 3 R 4 wherein each of R 3 and R 4 is independently H or lower alkyl, provided that R 2 is always adjacent to an OH group.
Inventors
- 👤 Kenneth J. Harrison
- 👤 Edward P. Raynes
- 👤 Frances C. Saunders
- 👤 David J. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:56
CPC Classifications
C; C09; C09K; C09K19/00; C09B; C09B1/00; C09B1/50; C09B1/503; C09B1/51; C09B1/515; C09B1/54; C09B1/545; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/20; C09K19/52; C09K19/60; C09K19/603
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
59 words
A material suitable for a guest-host liquid crystal device comprising a solution of a liquid crystal material and a pleochroic dye wherein the pleochroic dye comprises at least one compound having a formula: ##STR34## wherein R is H or lower alkyl; and each of R 1 and R 2 independently represents alkyl containing between 1 and 10 carbon atoms.
Claim 2
Dependent Claim
59 words
A material suitable for a guest-host liquid crystal device comprising a solution of a liquid crystal material and a pleochroic dye wherein the pleochroic dye comprises at least one compound having a formula: ##STR34## wherein R is H or lower alkyl; and each of R 1 and R 2 independently represents alkyl containing between 1 and 10 carbon atoms.
Claim 3
Dependent Claim
25 words
A material as claimed in claim 1 in which R 1 and R 2 are independently alkyl groups containing between 4 and 10 carbon atoms.
Claim 4
Dependent Claim
30 words
A material as claimed in claim 1 in which each of R 1 and R 2 is independently a group ##STR35## where R x and R y are alkyl groups.
Claim 5
Dependent Claim
23 words
A material as claimed in claim 1 in which the compound is 4,5-diamino-2,7-di-isobutyl-1,8-dihydroxyanthraquinone, the groups R 1 and R 2 both isobutyl groups.
Claim 6
Dependent Claim
26 words
A material as claimed in claim 1 in which the compound is 4,5-diamino-2,7-dinonyl-1,8-dihydroxyanthraquinone, the groups R 1 and R 2 being n-C 9 H 19 groups.
Claim 7
Dependent Claim
21 words
A material as claimed in claim 1 in which the liquid crystal material includes one or more cyanobiphenyl liquid crystal compounds.
Claim 8
Dependent Claim
24 words
A material as claimed in claim 6 in which the liquid crystal material is composed mainly, as a percentage by weight, of cyanobiphenyl compounds.
Claim 9
Dependent Claim
21 words
A material as claimed in claim 1 in which the liquid crystal material includes one or more cyanophenylcyclohexane liquid crystal compounds.
Claim 10
Dependent Claim
26 words
A liquid crystal material as claimed in claim 8 in which the liquid crystal material is composed mainly, as a percentage by weight, of cyanophenylcyclohexane compounds.
Claim 11
Dependent Claim
27 words
A material as claimed in claim 1 in which the liquid crystal material is a nematic material suitable for a Freedericksz effect or twisted nematic effect device.
Claim 12
Dependent Claim
40 words
A material as claimed in claim 1 in which the liquid crystal material is a long pitch cholesteric material suitable for a cholesteric-to-nematic phase change liquid crystal material formed of a mixture of a nematic material and a chiral material.
Claim 13
Dependent Claim
23 words
A material as claimed in claim 11 in which the nematic material is composed mainly, as a percentage by weight, of cyanobiphenyl compounds.
Claim 14
Dependent Claim
29 words
A material as claimed in claim 12 in which the chiral material is 4-[(+)-2-methylbutyl]-4'-cyanobiphenyl and forms less than 10% by weight of the mixture of nematic and chiral materials.
Claim 15
Dependent Claim
38 words
A material as claimed in claim 13 in which the nematic material is a material composed mainly of cyanobiphenyl compounds and the chiral material 4-(+)-2-methylbutyl-4'-cyanobiphenyl forms about 5% by weight of the mixture of nematic and chiral materials.
Claim 16
Dependent Claim
34 words
A material as claimed in claim 1 in which the pleochroic dye comprises a mixture of dyes of different color, at least one comprising a compound having Formula (I) as defined in claim 33.
Claim 17
Dependent Claim
19 words
A material as claimed in claim 15 in which the compound having Formula (I) is a blue dye compound.
Claim 18
Dependent Claim
19 words
A material as claimed in claim 16 in which the blue dye compound is selected from: 4,5-diamino-2,7-di-isobutyl-1,8-dihydroxyanthraquinone, and 4,5-diamino-2,7-dinonyl-1,8-dihydroxyanthraquinone.
Claim 19
Dependent Claim
26 words
A material as claimed in claim 15 in which the dye compound having Formula (I) is mixed together with a yellow dye and a red dye.
Claim 20
Dependent Claim
61 words
A material as claimed in claim 18 in which at least one of the yellow dye and red dye has a formula: ##STR36## wherein R is aryl or alkyl, Q is halogen, hydroxy, anino, alkylamino, dialkylamine, nitro, alkyl, or aryl, x is an integer of from 1 to 4 inclusive, and y is an integer of from 0 to 4 inclusive.
Claim 21
Dependent Claim
60 words
A material as claimed in claim 19 in which at least one of the yellow dye and the red dye comprises a compound having a formula: ##STR37## wherein R C and R D are groups selected from thiophenyl and 4-alkylthiophenyl groups and X 1 and X 2 are either both hydrogen or are groups selected from thiophenyl and 4-alkylthiophenyl groups.
Claim 22
Dependent Claim
59 words
A material as claimed in claim 20 in which the yellow dye comprises a dye compound of Formula (VI) as defined in claim 20, X 1 and X 2 being hydrogen, and the red dye comprises a dye compound of Formula (VI) as defined in claim 20, X 1 and X 2 being groups selected from thiophenyl and 4-alkylthiophenyl.
Claim 23
Dependent Claim
17 words
A material as claimed in claim 21 in which the blue dye comprises a compound selected from:
Claim 24
Dependent Claim
3 words
5-diamino-2,7-di-isobutyl-1,8-dihydroxyanthraquinone, and 4,5-diamino-2,7-dinonyl-1,8-dihydroxyanthraquinone.
Claim 25
Dependent Claim
3 words
5-diamino-2,7-di-isobutyl-1,8-dihydroxyanthraquinone, and 4,5-diamino-2,7-dinonyl-1,8-dihydroxyanthraquinone.
Claim 26
Dependent Claim
53 words
A liquid crystal electro-optical device comprising two electrically insulating substrates at least one of which is optically transparent, electrodes on the inner surfaces of the substrates and a film of dielectric material contained between the electrodes and the substrates, wherein the improvement comprises the dielectric material being material as claimed in claim 1.
Claim 27
Dependent Claim
20 words
A device as claimed in claim 23 in which the device is a Freedericksz effect or twisted nematic effect device.
Claim 28
Dependent Claim
29 words
A device as claimed in claim 23 in which the device is a cholesteric to nematic phase change effect device, the dielectric material being a long pitch cholesteric material.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |