Patent US5282707A successfully refreshed from Google Patents.
US3663390A
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Method of changing color play range of liquid crystal materials
Assignee: Westinghouse Electric Corp
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Filing: 1970-09-24
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Granted: 1972-05-16
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Expires: 1990-09-24
Abstract
Abstract Increasing dosages of X-ray radiation progressively lower the color-play range of cholesteric-phase liquid-crystal materials. The effect is enhanced when an effective amount of an iodinecontaining compound is used in the liquid-crystal material. Novel iodine-containing compounds are described, and articles are disclosed that give direct reading indication of the dosage of Xray radiation that they have received, without need for a separate development operation.
Inventors
- 👤 James L Fergason
- 👤 Newton N Goldberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:03
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/02; G01T1/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
19 words
A method as defined in claim 1, further characterized in that said cholesterogenic material is an iodine-containing cholesterogenic material.
Claim 2
Dependent Claim
23 words
A method as defined in claim 1, further characterized in that said cholesterogenic material is in the form of film 5-50 microns thick.
Claim 3
Dependent Claim
19 words
A method as defined in claim 3, further characterized in that said cholesterogenic material is an iodine-containing cholesterogenic material.
Claim 4
Dependent Claim
19 words
A method as defined in claim 4, characterized in that said iodine-containing cholesterogenic material consists essentially of cholesteryl 4-iodobenzoate.
Claim 5
Dependent Claim
38 words
A method as defined in claim 1, further characterized in that said dosage is a dosage preselected with regard to the composition and color performance of said material and the temperature environment of intended use of said 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) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |