US3963313A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Liquid crystal Schiffs bases
Assignee: Hoffmann La Roche Inc
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Filing: 1975-09-09
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Granted: 1976-06-15
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Expires: 1995-09-09
Abstract
Abstract Liquid crystal substances or compounds of the formula WHEREIN R is as hereinafter set forth, AS WELL AS COMPOSITIONS AND ELECTRO-OPTICAL APPARATUSES CONTAINING THEM ARE DESCRIBED.
Inventors
- 👤 Boller Arthur
- 👤 Hanspeter Scherrer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:18
CPC Classifications
C; C07; C07C; C07C255/00; C07C45/00; C07C45/51; C07C45/511; C07C45/513; C07C51/00; C07C51/58; C07C51/60; C09; C09K; C09K19/00; C09K19/04; C09K19/06; C09K19/08; C09K19/10; C09K19/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
85 words
An optical cell comprising liquid crystal means comprising one or more compounds selected from the group consisting of compounds of the formula ##SPC10## wherein R is ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isohexyl, n-heptyl or n-octyl, disposed between two plate means at least one of which plate means is transparent; means for controlling the optical activity of the cell; and said liquid crystal means having a helical structure in the direction perpendicular to the plate means and the surfaces of the plate means being wall oriented.
Claim 2
Dependent Claim
85 words
An optical cell comprising liquid crystal means comprising one or more compounds selected from the group consisting of compounds of the formula ##SPC10## wherein R is ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, isohexyl, n-heptyl or n-octyl, disposed between two plate means at least one of which plate means is transparent; means for controlling the optical activity of the cell; and said liquid crystal means having a helical structure in the direction perpendicular to the plate means and the surfaces of the plate means being wall oriented.
References Cited (Backward Citations)
US3795436A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-15 | 1979-12-15 | 1980-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-15 | 1983-12-15 | 1984-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-15 | 1987-12-15 | 1988-06-15 | $7700.00 | Window Closed / Lapsed |