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US5326600A
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Liquid crystal device
Assignee: Canon Inc
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Filing: 1992-11-02
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Granted: 1994-07-05
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Expires: 2012-11-02
Abstract
Abstract A liquid crystal device is constituted by a pair of substrates and a ferroelectric liquid crystal disposed between the substrates. At least one of the pair of substrates has thereon an alignment film of a polyimide having a recurring unit of the following formula (I): ##STR1## wherein R 1 denotes a tetravalent organic residue; and X 1 -X 8 independently denote an alkyl group having 1-15 carbon atoms, an alkoxy group having 1-15 carbon atoms, CF 3 group, halogen or hydrogen atom with the proviso that at least one of X 1 -X 4 is not hydrogen atom and at least one of X 5 -X 8 is not hydrogen atom.
Inventors
- 👤 Masanobu Asaoka
- 👤 Hideaki Takao
- 👤 Takeshi Togano
- 👤 Makoto Kojima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:07
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133711; G02F1/133723; C09; C09K; C09K2323/00; C09K2323/02; C09K2323/027; C09K2323/0271; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
128 words
A liquid crystal device, comprising: a pair of substrates and a ferroelectric liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide having a recurring unit of the following formula (I): ##STR22## wherein R 1 denotes a tetravalent organic residue; and X 1 -X 8 independently denote an alkyl group having 1-15 carbon atoms, an alkoxy group having 1-15 carbon atoms, CF 3 group, halogen or hydrogen atom, with the proviso that at least one of X 1 -X 4 is not hydrogen atom, at least one of X 5 -X 8 is not hydrogen atom, and at least one of X 2 , X 4 , X 5 and X 7 is not hydrogen atom.
Claim 2
Dependent Claim
128 words
A liquid crystal device, comprising: a pair of substrates and a ferroelectric liquid crystal disposed between the substrates; at least one of said pair of substrates having thereon an alignment film comprising a polyimide having a recurring unit of the following formula (I): ##STR22## wherein R 1 denotes a tetravalent organic residue; and X 1 -X 8 independently denote an alkyl group having 1-15 carbon atoms, an alkoxy group having 1-15 carbon atoms, CF 3 group, halogen or hydrogen atom, with the proviso that at least one of X 1 -X 4 is not hydrogen atom, at least one of X 5 -X 8 is not hydrogen atom, and at least one of X 2 , X 4 , X 5 and X 7 is not hydrogen atom.
Claim 3
Dependent Claim
21 words
A device according to claim 1, wherein R 1 in the formula (I) is selected from the group consisting of: ##STR23##
Claim 4
Dependent Claim
21 words
A device according to claim 1, wherein R 1 in the formula (I) is selected from the group consisting of: ##STR24##
Claim 5
Dependent Claim
25 words
A device according to claim 1, wherein at least one of X 1 -X 8 denotes an alkyl or alkoxy group having 1-10 carbon atoms.
Claim 6
Dependent Claim
25 words
A device according to claim 1, wherein at least one of X 1 -X 8 denotes an alkyl or alkoxy group having 1-5 carbon atoms.
Claim 7
Dependent Claim
23 words
A device according to claim 1, wherein said ferroelectric liquid crystal assumes a uniform alignment state under the action of the alignment film.
Claim 8
Dependent Claim
15 words
A device according to claim 6, wherein said alignment film has been subjected to rubbing.
Claim 9
Dependent Claim
17 words
A device according to claim 1, wherein said alignment film has a thickness of 30 Å-1 μm.
Claim 10
Dependent Claim
16 words
A device according to claim 1, wherein said alignment film has a thickness of 200-2000 Å.
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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) | 1997-07-04 | 1998-01-03 | 1998-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-04 | 2002-01-03 | 2002-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-04 | 2006-01-03 | 2006-07-05 | $7700.00 | Window Closed / Lapsed |