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Patent US4914224A successfully refreshed from Google Patents.
US4914224A
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Optically active carboxylic acid derivatives and liquid crystalline compositions comprising them
Assignee: Kawamura Institute of Chemical Research
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Filing: 1987-01-28
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Granted: 1990-04-03
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Expires: 2007-01-28
Abstract
Abstract An optically active carboxylic acid derivative represented by the general formula ##STR1## wherein R represents a normal alkyl group having 1 to 20 carbon atoms, m and n represent 0 or 1 but are not 1 at the same time, X represents a hydrogen or halogen atom, Y represents a hydrogen or fluorine atom, provided that when Y is a hydrogen atom, X is a halogen atom, and that when n is 0, Y is ahydrogen atom, and Q* represents an optically active alkyl or 1-alkoxyethyl group having an asymmetric carbon atom.
Inventors
- 👤 Tadao Shoji
- 👤 Sadao Takehara
- 👤 Toru Fujisawa
- 👤 Masashi Osawa
- 👤 Hiroshi Ogawa
- 👤 Yoshi Arai
- 👤 Jitsuo Kurokawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:49
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/12; C09K19/20; C09K19/2007; C09K19/2021
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
39 words
An optically active carboxylic acid derivative represented by the general formula ##STR20## wherein R represents a normal alkyl group having 5 to 20 carbon atoms, X represents a hydrogen or halogen atom, and Q* represents an optically active alkyl.
Claim 2
Dependent Claim
39 words
An optically active carboxylic acid derivative represented by the general formula ##STR20## wherein R represents a normal alkyl group having 5 to 20 carbon atoms, X represents a hydrogen or halogen atom, and Q* represents an optically active alkyl.
Claim 3
Dependent Claim
18 words
The compound of claim 1, wherein R represents a linear alkyl group having 5 to 18 carbon atoms.
Claim 4
Dependent Claim
19 words
The compound of claim 1, wherein Q* represents an optically active 1-methylpropyl group or an optically active 2-methylbutyl group.
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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) | 1993-04-02 | 1993-10-02 | 1994-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-04-02 | 1997-10-02 | 1998-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-04-02 | 2001-10-02 | 2002-04-03 | $7700.00 | Window Closed / Lapsed |