US4786348A
Expired / Lapsed
US
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Method of making transparent oriented sheets
Assignee: EIDP Inc
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Filing: 1987-01-05
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Granted: 1988-11-22
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Expires: 2007-01-05
Abstract
Abstract Highly oriented sheets are prepared by hot pressing a warp of filaments of liquid crystal polymers and optionally heat strengthening.
Inventors
- 👤 Robert R. Luise
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:48
CPC Classifications
B; B32; B32B; B32B33/00; B29; B29C; B29C43/00; B29C43/006; B29C67/00; B29C67/24; B32B38/00; B32B38/0036; B32B5/00; B32B5/02; B32B5/04; B32B5/12; D; D04; D04H; D04H3/00; D04H3/08; D04H3/14; B29K; B29K2105/00; B29K2105/0079; B29K2105/06; B32B2038/0052; B32B2038/0072; B32B2262/00; B32B2262/02; B32B2262/0276; B32B2305/00; B32B2305/55; B32B2307/00; B32B2307/40; B32B2307/412; B32B2307/42; B32B2307/50; B32B2307/514; B32B2307/516; B32B2307/54; B32B2307/70; B32B2307/706; B32B2309/00; B32B2309/02; B32B2309/12; B32B2429/00; B32B2597/00; B32B2605/00; B32B2605/08; Y; Y10; Y10S; Y10S428/00; Y10S428/91; Y10T; Y10T428/00; Y10T428/29; Y10T428/2904; Y10T428/2905; Y10T428/2913; Y10T428/2933; Y10T428/2964; Y10T428/2967; Y10T428/2969; Y10T442/00; Y10T442/60; Y10T442/643; Y10T442/699
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
38 words
A method for preparing a uniaxially oriented sheet comprising hot pressing a warp of melt extruded filaments from polymer capable of forming an optically anisotropic melt at a temperature and pressure sufficient to form a coherent transparent sheet.
Claim 2
Independent Claim
38 words
A method for preparing a uniaxially oriented sheet comprising hot pressing a warp of melt extruded filaments from polymer capable of forming an optically anisotropic melt at a temperature and pressure sufficient to form a coherent transparent sheet.
Claim 3
Dependent Claim
39 words
A method according to claim 1 wherein the hot-pressed sheet is heat strengthened by heating in a purged inert atmosphere at a temperature below the melting point for a period sufficient to increase tensile strength in the warp direction.
Claim 4
Dependent Claim
32 words
A method according to claim 1 wherein the temperature employed is below but within 20° C. of the melting endotherm and the pressure employed is at least 100 pounds per square inch.
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) | 1991-11-22 | 1992-05-23 | 1992-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-11-22 | 1996-05-23 | 1996-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-11-22 | 2000-05-23 | 2000-11-22 | $7700.00 | Window Closed / Lapsed |