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US4153343A
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US
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Liquid crystal dyestuffs and electro-optic devices incorporating same
Assignee: RCA Corp
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Filing: 1977-06-09
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Granted: 1979-05-08
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Expires: 1997-06-09
Abstract
Abstract Novel dyes of the formula ##STR1## wherein X is --NH, --NCH 3 , --S or --O; R 1 , R 2 , R 3 and R 4 independently at each occurrence can be hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro, --N(R) 2 wherein R is alkyl or two of R 1 to R 4 together can be part of an aromatic ring; R 5 and R 6 are hydrogen, fluoro, chloro, bromo or lower alkyl; and R 7 is hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro, --N(R 2 ), ##STR2## HYDROGEN, FLUORO, CHLORO, BROMO, ALKOXY, CYANO, NITRO, DI-ALKYLAMINO, ##STR3## can be added to known liquid crystal compositions to impart color to the mixtures and to improve contrast of a liquid crystal electro-optic device containing such mixtures.
Inventors
- 👤 Allen Bloom
- 👤 Ling K. Hung
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:31
CPC Classifications
C; C09; C09B; C09B29/00; C09B29/0025; C09B29/06; C09B29/08; C09B29/0805; C09B29/0807; C09B29/0809; C09B29/0811; C09B29/083; C09B31/00; C09B31/02; C09K; C09K19/00; C09K19/52; C09K19/60
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
107 words
In an electro-optic device field effect liquid comprising a crystal neamtic liquid crystal composition havng positive dielectric anistropy between two electrodes, the improvement which comprises a dyestuff dissolved in said composition of the formula ##STR12## wherein R 1 to R 4 independently at each occurrence can be hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro or dialkylamino or any adjacent two of R 1 to R 4 together can be part of an aromatic ring; X can be NH, NCH 3 , S or O; R 5 and R 6 independently can be hydrogen, fluoro, chloro, bromo, or lower alkyl; and R 7 can be alkoxy, dialkylamino, ##STR13##
Claim 2
Dependent Claim
107 words
In an electro-optic device field effect liquid comprising a crystal neamtic liquid crystal composition havng positive dielectric anistropy between two electrodes, the improvement which comprises a dyestuff dissolved in said composition of the formula ##STR12## wherein R 1 to R 4 independently at each occurrence can be hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro or dialkylamino or any adjacent two of R 1 to R 4 together can be part of an aromatic ring; X can be NH, NCH 3 , S or O; R 5 and R 6 independently can be hydrogen, fluoro, chloro, bromo, or lower alkyl; and R 7 can be alkoxy, dialkylamino, ##STR13##
Claim 3
Dependent Claim
15 words
A device according to claim 1 wherein X is S and R 7 is dialkylamino.
Claim 4
Dependent Claim
15 words
A device according to claim 1 wherein X is NH and R 7 is diethylamino.
Claim 5
Dependent Claim
95 words
A nematic liquid crystal composition comprising a nematic liquid crystal having positive dielectric anistropy having dissolved therein a compound of the formula ##STR14## wherein R 1 to R 4 independently at each occurrence can be hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro or dialkylamino or any adjacent two of R 1 and R 4 together can be part of an aromatic ring; X can be NH, NCH 3 , S or O; R 5 and R 6 independently can be hydrogen, fluoro, chloro, bromo or lower alkyl; and R 7 can be alkoxy, dialkylamino, ##STR15##
Claim 6
Dependent Claim
95 words
A nematic liquid crystal composition comprising a nematic liquid crystal having positive dielectric anistropy having dissolved therein a compound of the formula ##STR14## wherein R 1 to R 4 independently at each occurrence can be hydrogen, fluoro, chloro, bromo, alkoxy, cyano, nitro or dialkylamino or any adjacent two of R 1 and R 4 together can be part of an aromatic ring; X can be NH, NCH 3 , S or O; R 5 and R 6 independently can be hydrogen, fluoro, chloro, bromo or lower alkyl; and R 7 can be alkoxy, dialkylamino, ##STR15##
Claim 7
Dependent Claim
32 words
A composition according to claim 4 wherein the nematic liquid crystal is a mixture of p-methoxybenzylidene-p'-n-butylaniline, p-ethoxybenzylidene-p'-n-butylaniline and one or more p-alkoxybenzylidene-p'-cyanoaniline compounds having the formula ##STR16## wherein R is lower alkyl.
Claim 8
Dependent Claim
12 words
A composition according to claim 5 wherein the p-alkoxybenzylidene-p'-cyanoaniline compound is p-ethoxybenzylidene-p'-cyanoaniline.
References Cited (Backward Citations)
CA570914A
Cited
US3597044A
Cited
US3864022A
Cited
US3833287A
Cited
US3960750A
Cited
US3960751A
Cited
DE2627215A1
Cited
US4032470A
Cited
DE2631428A1
Cited
US4098301A
Cited
US4116861A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-07 | 1982-11-06 | 1983-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-07 | 1986-11-06 | 1987-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-07 | 1990-11-06 | 1991-05-08 | $7700.00 | Window Closed / Lapsed |