US3790432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reinforced polyquinoxaline gasket and method of preparing the same
Assignee: National Aeronautics and Space Administration
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Filing: 1971-12-30
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Granted: 1974-02-05
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Expires: 1991-12-30
Abstract
Abstract A gasket or seal resistant to ionizing radiation and liquid hydrogen temperatures is made up of a laminated polyquinoxaline resin-fiberglass cloth body portion and a molded polyquinoxaline encapsulating film. The laminated body is prepared by stacking thin sheets of the resin alternately with fiberglass cloth and heating the assembly under pressure with the temperature, pressure and resin film thickness being controlled so that only partial impregnation of the fiberglass cloth is produced. The encapsulating resin film is preheated at about 300* F and applied to the laminate body by molding at a temperature of about 625* F, after which the molded gasket is deflashed and postcured by heating at 675* to 700* F.
Inventors
- 👤 J Fletcher
- 👤 Auken R Van
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:54
CPC Classifications
B; B29; B29C; B29C70/00; B29C70/003; B32; B32B; B32B27/00; B32B27/06; B32B27/08; B32B27/12; B29K; B29K2309/00; B29K2309/08; B32B2262/00; B32B2262/10; B32B2262/101; B32B2581/00; Y; Y10; Y10T; Y10T428/00; Y10T428/21; Y10T428/215; Y10T428/23; Y10T428/239; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/269; Y10T442/00; Y10T442/60; Y10T442/659; Y10T442/67
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
20 words
The gasket of claim 1 wherein said layers of resin in said laminated body are 1.8 to 2.2 mils thick.
Claim 2
Independent Claim
118 words
The method of preparing a gasket which comprises: a. stacking alternating sheets of uncured polyquinoxaline resin and fiberglass cloth; b. heating the resulting stacked array at a temperature of 340* to 360* F while compressing said sheets together at a pressure of 25 to 35 psi to form a partially impregnated, laminated body; c. covering the entire surface of said body with a film of polyquinoxaline resin, said film having been heated to a temperature of 280* to 320* F; d. molding the film covered body at a temperature of 600* to 650* F and a pressure of 25 to 35 psi; e. post-curing the molded gasket body by heating at a temperature of 675* to 700* F.
Claim 3
Dependent Claim
11 words
The method of claim 3 wherein said polyquinoxaline has the formula
Claim 4
Dependent Claim
20 words
The method of claim 4 wherein the thickness of said resin sheet in said array is 1.8 to 2.2 mils.
Claim 5
Dependent Claim
29 words
The method of claim 5 wherein a portion of said body is cut away to leave only a gasket blank prior to covering the body surface with said film.
Claim 6
Dependent Claim
14 words
The method of claim 6 wherein said film is at least 3.5 mils thick.
Claim 7
Dependent Claim
15 words
The method of claim 6 wherein said molded body is deflashed prior to post curing.
Claim 8
Dependent Claim
24 words
The method of claim 6 wherein stacked array is heated at a temperature of about 350* F and a pressure of about 30 psi.
Claim 9
Dependent Claim
24 words
The method of claim 6 wherein said body is molded at a temperature of about 625* F and a pressure of about 30 psi.
References Cited (Backward Citations)
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US3511733A
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Cited
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Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |