US4460492A
Expired / Lapsed
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Low viscosity lyotropic cholesteric liquid crystal compositions
Assignee: Temple University
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Filing: 1981-11-19
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Granted: 1984-07-17
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Expires: 2001-11-19
Abstract
Abstract A low viscosity, short pitch, cholesteric liquid crystal composition consisting of an alkali cromoglycate dissolved in water or water with a polar solvent, together with an optically active solute in sufficient concentration to render the cromoglycate cholesteric. Suitable compositions will reflect light in the visible spectrum and may be magnetically, electrically, or thermally addressed to produce optical effects therein.
Inventors
- 👤 Mortimer M. Labes
- 👤 Heewon Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:45
CPC Classifications
C; C09; C09K; C09K19/00; C09K19/52; C09K19/54
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
82 words
A low viscosity cholesteric liquid crystal composition comprising a single phase, low viscosity solution of alkali cromoglycate in a water-based polar solvent, said cromoglycate being in a nematic liquid crystal state, and said solution further including at least one soluble chiral modifier selected from the group consisting of 1-amino acids and the enantiomers or optical isomers thereof and di- and tripeptides (polyamino acids), said modifier being present in an amount sufficient to produce a short pitch cholesteric effect in the visible spectrum.
Claim 2
Dependent Claim
82 words
A low viscosity cholesteric liquid crystal composition comprising a single phase, low viscosity solution of alkali cromoglycate in a water-based polar solvent, said cromoglycate being in a nematic liquid crystal state, and said solution further including at least one soluble chiral modifier selected from the group consisting of 1-amino acids and the enantiomers or optical isomers thereof and di- and tripeptides (polyamino acids), said modifier being present in an amount sufficient to produce a short pitch cholesteric effect in the visible spectrum.
Claim 3
Dependent Claim
12 words
A composition, as recited in claim 1, wherein said solvent is water.
Claim 4
Dependent Claim
14 words
A composition, as recited in claim 1, wherein said solvent is a water-glycol mixture.
Claim 5
Dependent Claim
31 words
A composition, as recited in claim 1, wherein said solvent comprises water in combination with one or more members from the group consisting of alcohol, glycol, dimethylformamide, dimethylsulfoxide, dioxane, and acetonitrile.
Claim 6
Dependent Claim
14 words
A composition, as recited in claim 1, wherein said alkali cromoglycate is sodium cromoglycate.
Claim 7
Dependent Claim
12 words
A composition, as recited in claim 5, wherein said solvent is water.
Claim 8
Dependent Claim
14 words
A composition, as recited in claim 5, wherein said solvent is a water-glycol mixture.
Claim 9
Dependent Claim
35 words
The composition of claim 1, wherein said chiral modifier is selected from the group consisting of trans-4-hydroxyl-1-proline, 1-alanine, 1-lysine-HCl, and 1-proline, and said amount is sufficient to produce a pitch of 10 microns or less.
Claim 10
Dependent Claim
22 words
The composition of claim 1, wherein the amount of chiral modifier is sufficient to produce a pitch of 10 microns or less.
Claim 11
Dependent Claim
23 words
The composition of claim 9, wherein said amount ranges from 5% to 30%, by weight, based upon the total weight of the composition.
Claim 12
Dependent Claim
40 words
A composition as recited in any one of claims 1, 8, 9, 10, 2, 3, 4, 5, 6, and 7, wherein said cromoglycate comprises 7-27%, by weight, of said composition and said modifier(s) comprise 5-30%, by weight, of said composition.
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) | 1987-07-17 | 1988-01-16 | 1988-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-17 | 1992-01-16 | 1992-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-17 | 1996-01-16 | 1996-07-17 | $7700.00 | Window Closed / Lapsed |