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US4147656A
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Mixtures of nematic liquid crystal materials
Assignee: Northrop Grumman Guidance and Electronics Co Inc
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Filing: 1978-04-27
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Granted: 1979-04-03
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Expires: 1998-04-27
Abstract
Abstract Liquid crystal mixtures are disclosed which contain 30-60% of a Schiff's base nematic liquid crystal compound, 25-65% of a second nematic liquid crystal compound selected from the classes of azoxy, ester and biphenyl, and 5-15% of a triphenyl compound to raise the isotropic transition temperature. This combination results in liquid crystal compositions having unexpectedly wide nematic temperature ranges.
Inventors
- 👤 Ralph E. Aldrich
- 👤 William J. Cumming
- 👤 William A. Simmons, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:06
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/42; C09K19/48
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
169 words
A nematic liquid crystal composition having a freezing point at which said composition changes from a nematic liquid phase to a solid phase of at most about -50° C. and an isotropic transition point of at least about 80° C. which, based upon 100% by weight, consists essentially of: a. from about 10% to about 15% by weight of bis(4'-n-octyloxybenzal)-2-chloro-1,4-phenylenediamine; b. from about 25% to about 65% of a Schiff's base nematic liquid crystal compound represented by the structural formula, ##STR18## wherein R is selected from the group consisting of C 1 -C 8 alkoxy and C 1 -C 8 alkyl ester and R' is selected from the group consisting of C 1 -C 8 alkyl and C 1 -C 8 alkyl ester; and, c. from about 20% to about 65% Licristal 9, a mixture having a composition consisting essentially of the following ingredients, based upon 100%, by weight: ______________________________________
4'-n-pentylphenyl ester of
anisic acid 55-60%
4'-n-pentylphenyl ester of
4-hexyloxybenzoic acid 25-30%
(2'-cyano-4'butylphenyl)ester
of 4-(4-hexanoyloxybenzoyloxy)-
benzoic acid 10-15%.
______________________________________
Claim 2
Dependent Claim
169 words
A nematic liquid crystal composition having a freezing point at which said composition changes from a nematic liquid phase to a solid phase of at most about -50° C. and an isotropic transition point of at least about 80° C. which, based upon 100% by weight, consists essentially of: a. from about 10% to about 15% by weight of bis(4'-n-octyloxybenzal)-2-chloro-1,4-phenylenediamine; b. from about 25% to about 65% of a Schiff's base nematic liquid crystal compound represented by the structural formula, ##STR18## wherein R is selected from the group consisting of C 1 -C 8 alkoxy and C 1 -C 8 alkyl ester and R' is selected from the group consisting of C 1 -C 8 alkyl and C 1 -C 8 alkyl ester; and, c. from about 20% to about 65% Licristal 9, a mixture having a composition consisting essentially of the following ingredients, based upon 100%, by weight: ______________________________________
4'-n-pentylphenyl ester of
anisic acid 55-60%
4'-n-pentylphenyl ester of
4-hexyloxybenzoic acid 25-30%
(2'-cyano-4'butylphenyl)ester
of 4-(4-hexanoyloxybenzoyloxy)-
benzoic acid 10-15%.
______________________________________
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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) | 1982-04-02 | 1982-10-02 | 1983-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-02 | 1986-10-02 | 1987-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-02 | 1990-10-02 | 1991-04-03 | $7700.00 | Window Closed / Lapsed |