US4354740A
Expired / Lapsed
US
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Surface alignment process for liquid crystal displays
Assignee: Ametek Inc
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Filing: 1980-05-23
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Granted: 1982-10-19
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Expires: 2000-05-23
Abstract
Abstract Homeotropic surface alignment is provided in liquid crystal display cells, utilizing high temperature peripheral sealing material, by fabricating the empty cell prior to introducing a solution of a homeotropic-aligning surfactant dissolved in a volatile solvent. The solvent is evaporated to provide a surfactant film on the cell cavity interior surfaces. The cell is then filled with the liquid crystal material and the cell is sealed.
Inventors
- 👤 Herbert S. Cole, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 00:06
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/13; G02F1/133; G02F1/1333; G02F1/1337; G02F1/133711; G02F1/133719; Y; Y10; Y10S; Y10S359/00; Y10S359/90
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
101 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution; (d) evaporating the volatile carrier solvent to deposit the surfactant on the interior cell cavity surfaces; (e) filling the cell cavity with the liquid crystal material, said liquid crystal material being essentially devoid of any surfactants; and (f) sealing the fill hole.
Claim 2
Independent Claim
101 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution; (d) evaporating the volatile carrier solvent to deposit the surfactant on the interior cell cavity surfaces; (e) filling the cell cavity with the liquid crystal material, said liquid crystal material being essentially devoid of any surfactants; and (f) sealing the fill hole.
Claim 3
Dependent Claim
25 words
The method of claim 1, wherein step (b) includes the step of dissolving up to about 1 percent, by volume, of surfactant in the solvent.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein the solvent of step (b) is distilled water.
Claim 5
Dependent Claim
50 words
The method of claim 1, wherein step (a) includes the steps of providing a pair of spaced-apart substrates having the edges thereof in registration; and sealing the periphery of the registered substrates with a material requiring a sealing temperature greater than the temperature at which decomposition of the surfactant occurs.
Claim 6
Dependent Claim
13 words
The method of claim 4, wherein the sealing material is a glass frit.
Claim 7
Dependent Claim
25 words
The method of claim 4, further including the step of depositing electrodes upon the interior-facing surfaces of the substrates prior to sealing the periphery thereof.
Claim 8
Dependent Claim
16 words
The method of claim 1, wherein the liquid crystal material is a cholesteric-nematic liquid crystal material.
Claim 9
Independent Claim
121 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution by: immersing the cell in the solution; placing the cell under a vacuum; and then returning the cell to ambient atmospheric pressure to fill the cell cavity with the solution; (d) evaporating the volatile carrier solvent to deposit the surfactant on the interior cell cavity surfaces; (e) filling the cell cavity with the liquid crystal material; and (f) sealing the fill hole.
Claim 10
Independent Claim
121 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution by: immersing the cell in the solution; placing the cell under a vacuum; and then returning the cell to ambient atmospheric pressure to fill the cell cavity with the solution; (d) evaporating the volatile carrier solvent to deposit the surfactant on the interior cell cavity surfaces; (e) filling the cell cavity with the liquid crystal material; and (f) sealing the fill hole.
Claim 11
Dependent Claim
24 words
The method of claim 8, wherein step (b) includes the step of dissolving up to 1 percent, by volume, of surfactant in the solution.
Claim 12
Dependent Claim
14 words
The method of claim 8, wherein the solvent of step (b) is distilled water.
Claim 13
Dependent Claim
50 words
The method of claim 8, wherein step (a) includes the steps of providing a pair of spaced-apart substrates having the edges thereof in registration; and sealing the periphery of the registered substrates with a material requiring a sealing temperature greater than the temperature at which decomposition of the surfactant occurs.
Claim 14
Dependent Claim
13 words
The method of claim 11, wherein the sealing material is a glass frit.
Claim 15
Dependent Claim
25 words
The method of claim 11, further including the step of depositing electrodes upon the interior-facing surfaces of the substrates prior to sealing the periphery thereof.
Claim 16
Dependent Claim
16 words
The method of claim 8, wherein the liquid crystal material is a cholesteric-nematic liquid crystal material.
Claim 17
Independent Claim
135 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution; (d) evaporating the volatile carrier solution by: placing the cell under vacuum; heating the cell to a preselected temperature while under vacuum; and maintaining the cell under vacuum and at the preselected temperature for a time interval selected to evaporate the solvent and leave the homeotropic alignment surfactant deposited as a film upon the interior surfaces of said cell cavity; (e) filling the cell cavity with the liquid crystal material; and (f) sealing the fill hole.
Claim 18
Independent Claim
135 words
A method for providing, in one display condition, homeotropic alignment to liquid crystal material filling a display cell, comprising the steps of: (a) providing an empty cell having a fill hole communicating to an empty cavity therein; (b) dissolving a surfactant, selected to provide homeotropic alignment, in a volatile carrier solvent; (c) filling the cell cavity with the solution; (d) evaporating the volatile carrier solution by: placing the cell under vacuum; heating the cell to a preselected temperature while under vacuum; and maintaining the cell under vacuum and at the preselected temperature for a time interval selected to evaporate the solvent and leave the homeotropic alignment surfactant deposited as a film upon the interior surfaces of said cell cavity; (e) filling the cell cavity with the liquid crystal material; and (f) sealing the fill hole.
Claim 19
Dependent Claim
19 words
The method of claim 15, wherein the heating step is carried out at a preselected temperature about 80° C.
Claim 20
Dependent Claim
25 words
The method of claim 15, wherein step (b) includes the step of dissolving up to about 1 percent, by volume, of surfactant in the solvent.
Claim 21
Dependent Claim
14 words
The method of claim 15, wherein the solvent of step (b) is distilled water.
Claim 22
Dependent Claim
50 words
The method of claim 15, wherein step (a) includes the steps of providing a pair of spaced-apart substrates having the edges thereof in registration; and sealing the periphery of the registered substrates with a material requiring a sealing temperature greater than the temperature at which decomposition of the surfactant occurs.
Claim 23
Dependent Claim
13 words
The method of claim 15, wherein the sealing material is a glass frit.
Claim 24
Dependent Claim
25 words
The method of claim 15, further including the step of depositing electrodes upon the interior-facing surfaces of the substrates prior to sealing the periphery thereof.
Claim 25
Dependent Claim
16 words
The method of claim 15, wherein the liquid crystal material is a cholesteric-nematic liquid crystal material.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-10-18 | 1986-04-19 | 1986-10-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-10-18 | 1990-04-19 | 1990-10-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-10-18 | 1994-04-19 | 1994-10-19 | $7700.00 | Window Closed / Lapsed |