US4091847A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for filling dynamic scattering liquid crystal cells
Assignee: RCA Corp
•
Filing: 1976-11-22
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Granted: 1978-05-30
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Expires: 1996-11-22
Abstract
Abstract A dynamic scattering liquid crystal cell is filled from a single fill port by first applying a film of a mixture of at least two resistivity dopants, each having different ions, to the cell walls, then filling the cell with a liquid crystal composition containing both dopants.
Inventors
- 👤 Howard Sorkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:46
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1341; C; C09; C09K; C09K19/00; C09K19/52; C09K19/58; C09K19/582; C09K2323/00; C09K2323/05; C09K2323/057
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
130 words
In the process whereby a dynamic scattering liquid crystal cell comprising a layer of liquid crystal composition having negative dielectric anisotropy between two electrodes is filled from a single fill port by evacuating said cell, immersing said evacuated cell in a solution of an ionic dopant in a volatile solvent to fill the cell with said solution, evaporating the solvent leaving a film of said dopant on the walls of the cell, evacuating the cell and filling said inner-coated evacuated cell by immersing it in a dynamic scattering liquid crystal composition containing an ionic dopant, the improvement which comprises employing as the ionic dopant in both the volatile solvent and the liquid crystal composition the same-- has been substituted therefor, mixture of at least two ionic dopants having different ions.
Claim 2
Dependent Claim
130 words
In the process whereby a dynamic scattering liquid crystal cell comprising a layer of liquid crystal composition having negative dielectric anisotropy between two electrodes is filled from a single fill port by evacuating said cell, immersing said evacuated cell in a solution of an ionic dopant in a volatile solvent to fill the cell with said solution, evaporating the solvent leaving a film of said dopant on the walls of the cell, evacuating the cell and filling said inner-coated evacuated cell by immersing it in a dynamic scattering liquid crystal composition containing an ionic dopant, the improvement which comprises employing as the ionic dopant in both the volatile solvent and the liquid crystal composition the same-- has been substituted therefor, mixture of at least two ionic dopants having different ions.
Claim 3
Dependent Claim
29 words
A process according to claim 1 wherein the doped liquid crystal composition has a resistivity of from about 1 × 10 8 to about 5 × 10 10 ohm-cm.
Claim 4
Dependent Claim
18 words
A process according to claim 1 wherein the liquid crystal composition is a mixture containing p-methoxybenzylidine-p'-butylaniline, and p-ethoxybenzylidine-p'-butylaniline.
Claim 5
Dependent Claim
16 words
A process according to claim 1 wherein the liquid crystal composition contains p-methoxybenzylidine-p'-n-butylaniline, p-ethoxybenzylidine-p'-aminophenylbutyrate and p-butoxybenzylidine-p'-aminophenylhexanoate.
Claim 6
Dependent Claim
22 words
A process according to claim 1 wherein the liquid crystal composition containing an ionic dopant contains in addition a homeotropic aligning agent.
Claim 7
Dependent Claim
18 words
A process according to claim 4 wherein the ionic dopants are hexadecylpyridinium tetraphenyl borate and tetraheptyl ammonium bromide.
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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) | 1981-05-29 | 1981-11-28 | 1982-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-29 | 1985-11-28 | 1986-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-29 | 1989-11-28 | 1990-05-30 | $7700.00 | Window Closed / Lapsed |