Patent US3708370A successfully refreshed from Google Patents.
US3708370A
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Process for bonding surfaces with polyimide prepolymers
Assignee: Northrop Grumman Space and Mission Systems Corp
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Filing: 1971-08-06
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Granted: 1973-01-02
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Expires: 1991-08-06
Abstract
Abstract This invention relates to a high-temperature adhesive composition and to a method using same which comprises lowmolecular weight polyimide prepolymers obtained by coreacting a polyfunctional amine, a polyanhydride and a monoanhydride characterized by the formula: WHEREIN R is selected from the group consisting of hydrogen and lower alkyl radicals.
Inventors
- 👤 H Lubowitz
- 👤 E Burns
- 👤 J Jones
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:08
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; C08G73/101; C08G73/1014; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31551; Y10T428/31645; Y10T428/31721
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
22 words
The process of claim 1 further characterized in that the polyfunctional amine is 4,4''-methylenedianiline and the polyanhydride is 3,3'' ,4,4''-benzophenone tetracarboxylic-acid dianhydride.
Claim 2
Dependent Claim
32 words
The process of claim 1 further characterized in that the polyfunctiOnal amine is 4,4''-oxydianiline, the polyanhydride is 1,4,5,8-napthaline tetracarboxylic dianhydride and the monoanhydride has the formula wherein R is a methyl radical.
Claim 3
Dependent Claim
33 words
The process of claim 1 further characterized in that a reinforcing material impregnated with said polyimide prepolymer is placed between the surfaces to be bonded prior to applying pressure at an elevated temperature.
Claim 4
Dependent Claim
16 words
The process of claim 1 further characterized in that that the reinforcing material is glass cloth.
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) | 1976-01-02 | 1976-07-03 | 1977-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-02 | 1980-07-03 | 1981-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-02 | 1984-07-03 | 1985-01-02 | $7700.00 | Window Closed / Lapsed |