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US4490305A
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Liquid-crystalline halogen compounds, process for their preparation, dielectrics containing these, and electro-optical display element
Assignee: Merck Patent GmbH
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Filing: 1982-09-15
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Granted: 1984-12-25
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Expires: 2002-09-15
Abstract
Abstract Liquid-crystalline halogen compounds of the formula ##STR1## wherein the ring A is 1,4-phenylene or trans-1,4-cyclohexylene; R 1 is alkyl or alkoxy each of 1 to 12 carbon atoms or, when A is 1,4-phenylene, is also cyano; R 2 is alkyl or alkoxy each of 1 to 12 carbon atoms or, when A is 1,4-cyclohexylene, is also chlorine or bromine; and X is fluorine, chlorine or hydrogen; with the proviso that at least one of the substituents R 2 and X is a halogen atom are valuable components in liquid-crystalline dielectrics.
Inventors
- 👤 Rudolf Eidenschink
- 👤 Michael Romer
- 👤 Georg Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:34
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/30; C09K19/3001; C09K19/3003; C07; C07C; C07C17/00; C07C17/093; C07C205/00; C07C205/06; C07C25/00; C07C25/18; C07C43/00; C07C43/02; C07C43/20; C07C43/225; C09K19/10; C09K19/12
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
51 words
A liquid-crystalline halogen compound of the formula ##STR22## wherein R 1 is alkyl or alkoxy each of 1 to 12 carbon atoms or cyano; and R 2 is alkyl or alkoxy each of 1 to 12 carbon atoms; with the proviso that R 1 and R 2 are not simultaneously methyl.
Claim 2
Dependent Claim
51 words
A liquid-crystalline halogen compound of the formula ##STR22## wherein R 1 is alkyl or alkoxy each of 1 to 12 carbon atoms or cyano; and R 2 is alkyl or alkoxy each of 1 to 12 carbon atoms; with the proviso that R 1 and R 2 are not simultaneously methyl.
Claim 3
Dependent Claim
16 words
A liquid-crystalline halogen compound of claim 1 wherein R 1 is alkyl of 3-8 carbon atoms.
Claim 4
Dependent Claim
12 words
A compound of claim 1, wherein R 1 is alkyl or alkoxy.
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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) | 1987-12-25 | 1988-06-25 | 1988-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-25 | 1992-06-25 | 1992-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-25 | 1996-06-25 | 1996-12-25 | $7700.00 | Window Closed / Lapsed |