Patent US3000016A successfully refreshed from Google Patents.
Patent US4668426A successfully refreshed from Google Patents.
US4668426A
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US
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Liquid crystalline substances
Assignee: Werk fuer Fernsehelektronik im VEB Kombinat Mikroelektronik VEB
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Filing: 1985-03-29
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Granted: 1987-05-26
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Expires: 2005-03-29
Abstract
Abstract Nematic liquid crystalline substances as additives in mixtures for electro-optical systems for the rendition of numbers, symbols and images. The additives provide new liquid crystalline substances of broad mesophase ranges which improve the chemical stability of the substance mixtures. It has been found that liquid crystalline 5-alkyl-pyridine-2-carboxylic acid esters of the general formula ##STR1## are suitable for utilization in mixtures for electro-optical displays for the rendition of numbers, symbols and images.
Inventors
- 👤 Dietrich Demus
- 👤 Horst Zaschke
- 👤 Reinhard Paschke
- 👤 Adalbert Wiegeleben
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:52
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/60; C07D213/78; C07D213/79; C07D401/00; C07D401/02; C07D401/12; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/34; C09K19/3441; C09K19/3444; C09K19/345; C09K19/3458
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
10 words
Liquid crystalline 5-alkyl-pyridine-2-carboxylic acid esters of the general formula ##STR12##
Claim 2
Dependent Claim
10 words
Liquid crystalline 5-alkyl-pyridine-2-carboxylic acid esters of the general formula ##STR12##
Claim 3
Dependent Claim
15 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR13## and n=4.
Claim 4
Dependent Claim
15 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR14## and n=5.
Claim 5
Dependent Claim
15 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR15## and n=6.
Claim 6
Dependent Claim
15 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR16## and n=7.
Claim 7
Dependent Claim
15 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR17## and n=8.
Claim 8
Dependent Claim
21 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR18## and R 1 =--OC 4 H 9 .
Claim 9
Dependent Claim
21 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR19## and R 1 =--OC 5 H 11 .
Claim 10
Dependent Claim
21 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR20## and R 1 =--OC 6 H 13 .
Claim 11
Dependent Claim
21 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR21## and R 1 =--OC 8 H 17 .
Claim 12
Dependent Claim
17 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR22## and R 1 =CN.
Claim 13
Dependent Claim
13 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR23##
Claim 14
Dependent Claim
13 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR24##
Claim 15
Dependent Claim
13 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR25##
Claim 16
Dependent Claim
13 words
A liquid crystalline ester according to claim 1, wherein in formula I ##STR26##
Claim 17
Dependent Claim
14 words
A mixture comprising an ester according to claim 1 and other liquid crystalline substances.
Claim 18
Dependent Claim
18 words
An electro-optical device for the rendition of numbers, symbols or images containing a mixture according to claim 16.
References Cited (Backward Citations)
US4001137A
Cited
US3915883A
Cited
WO1982000654A1
Cited
GB2092169A
Cited
EP0056501A2
Cited
JPS60109569A
Cited
JPS60149564A
Cited
EP0164721A2
Cited
JPS6168467A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-05-25 | 1990-11-24 | 1991-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-05-25 | 1994-11-24 | 1995-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-05-25 | 1998-11-24 | 1999-05-26 | $7700.00 | Window Closed / Lapsed |