US4105299A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-optical devices containing methine arylidene dyes
Assignee: 3M Co
•
Filing: 1977-04-11
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Granted: 1978-08-08
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Expires: 1997-04-11
Abstract
Abstract Methine 4-nitro-arylidene dyes having certain substituents in the 2 position of the arylidene group are found to be pleochroic and to form guest-host combinations with dielectrically positive anisotropic nematic liquid crystals. These combinations are employed in electro-optical display devices.
Inventors
- 👤 William A. Huffman
- 👤 Harvey A. Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:41
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/52; C09K19/60
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
140 words
In an electro-optical device wherein an electrical field is imposed or withdrawn from action on a cell comprising liquid crystalline material having dissolved therein a pleochroic dye between transparent-electrode coated glass plates the improvement wherein the liquid crystalling material has net positive dieelectric anissotropy and comprises at least one nematic liquid crystallinehaving positive dielectric anisotropy and the dissolved pleochroic dye has the general formula ##STR9## wherein: Z represents the atoms necessary to complete a mono- or polycyclic dihydroheterocyclic nucleus having 5 to 6 atoms in the ring including the N of the formula where R 1 is an alkyl, substituted alkyl, alkenyl, or aryl group; m is 0 or 1; k is 0, 1 or 2; T is selected from CF 3 or CN and R 2 and R 3 are hydrogen or together constitute a condensed carbocyclic aromatic ring.
Claim 2
Dependent Claim
140 words
In an electro-optical device wherein an electrical field is imposed or withdrawn from action on a cell comprising liquid crystalline material having dissolved therein a pleochroic dye between transparent-electrode coated glass plates the improvement wherein the liquid crystalling material has net positive dieelectric anissotropy and comprises at least one nematic liquid crystallinehaving positive dielectric anisotropy and the dissolved pleochroic dye has the general formula ##STR9## wherein: Z represents the atoms necessary to complete a mono- or polycyclic dihydroheterocyclic nucleus having 5 to 6 atoms in the ring including the N of the formula where R 1 is an alkyl, substituted alkyl, alkenyl, or aryl group; m is 0 or 1; k is 0, 1 or 2; T is selected from CF 3 or CN and R 2 and R 3 are hydrogen or together constitute a condensed carbocyclic aromatic ring.
Claim 3
Dependent Claim
30 words
An electro-optical device according to claim 1 wherein the Z of the pleochroic dye is --CH═CH--, --CH═CH--CH═CH--, ##STR10## and R 4 is H, alkyl or alkoxy of 1-2 carbon atoms.
References Cited (Backward Citations)
US2400877A
Cited
US2544659A
Cited
US3597044A
Cited
US3703329A
Cited
US3833287A
Cited
US3960750A
Cited
US3960751A
Cited
US3963314A
Cited
US4032219A
Cited
US4003633A
Cited
DE2627215A1
Cited
US4032470A
Cited
US4033948A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-08-07 | 1982-02-06 | 1982-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-08-07 | 1986-02-06 | 1986-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-08-07 | 1990-02-06 | 1990-08-08 | $7700.00 | Window Closed / Lapsed |