US4402849A
Expired / Lapsed
US
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Liquid-crystalline tetrahydroquinazolines
Assignee: Merck Patent GmbH
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Filing: 1980-12-19
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Granted: 1983-09-06
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Expires: 2000-12-19
Abstract
Abstract Liquid-crystalline tetrahydroquinazolines of the formula ##STR1## wherein R 1 is alkyl, alkoxy, alkanoyloxy or alkoxycarbonyloxy of up to 8 carbon atoms in each case, CN, CF 3 , halogen or NO 2 ; and R 2 is alkyl of up to 10 carbon atoms are valuable components for liquid crystalline dielectrics.
Inventors
- 👤 Joachim Krause
- 👤 Ludwig Pohl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:56
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/34; C09K19/3441; C09K19/345; C09K19/3472; C07; C07D; C07D239/00; C07D239/70; C07D239/72; C07D239/74
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
46 words
A tetrahydroquinazoline of the formula ##STR7## wherein R 1 is alkyl, alkoxy, alkanoyloxy or alkoxycarbonyloxy of up to 8 carbon atoms in each case, CN, CF 3 , F, Cl, Br or NO 2 ; and R 2 is alkyl of up to 10 carbon atoms.
Claim 2
Dependent Claim
46 words
A tetrahydroquinazoline of the formula ##STR7## wherein R 1 is alkyl, alkoxy, alkanoyloxy or alkoxycarbonyloxy of up to 8 carbon atoms in each case, CN, CF 3 , F, Cl, Br or NO 2 ; and R 2 is alkyl of up to 10 carbon atoms.
Claim 3
Dependent Claim
10 words
A tetrahydroquinazoline of claim 1 wherein R 1 is CN.
Claim 4
Dependent Claim
19 words
A tetrahydroquinazoline of claim 1, wherein R 1 is alkyl, alkoxy or alkanoyloxy of up to 6 carbon atoms.
Claim 5
Dependent Claim
20 words
A tetrahydroquinazoline of claim 1, wherein R 1 is CN, CF 3 , F, Cl, Br or NO 2 .
Claim 6
Dependent Claim
23 words
In a liquid-crystalline dielectric comprising a mixture of liquid-crystalline components, the improvement whrein at least one component is a tetrahydroquinazoline of claim 1.
Claim 7
Dependent Claim
60 words
A liquid-crystalline dielectric of claim 5, comprising 1 to 50 percent by weight of a tetrahydroquinazoline of the formula ##STR8## wherein R 1 is alkyl, alkoxy, alkanoyloxy or alkoxycarbonyloxy of up to 8 carbon atoms in each case, CN, CF 3 , F, Cl, Br or NO 2 ; and R 2 is alkyl of up to 10 carbon atoms.
Claim 8
Dependent Claim
28 words
In an electro-optical display element having a liquid crystal cell which is based on a liquid-crystalline dielectric, the improvement wherein the liquid-crystalline dielectric is that of claim 5.
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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) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |