US3616196A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sheets and laminates of resinous and fibrous materials
Assignee: EIDP Inc
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Filing: 1968-11-27
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Granted: 1971-10-26
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Expires: 1988-11-27
Abstract
Abstract (A) Sheets of fibrous material impregnated with a polymeric precursor of a polyimide resin, that may be partially cured if desired, wherein such polymeric precursor has inert, thermally stable, colloidal particles dispersed therein and (B) unitary polyimide laminates prepared from a plurality of such sheets.
Inventors
- 👤 George C Sun
- 👤 Theodore Shell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:54
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/24; C08J5/241; C08J5/244; C08J5/249; C08J2379/00; C08J2379/04; C08J2379/08; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24132; Y10T428/31504; Y10T428/31551; Y10T428/31623; Y10T442/00; Y10T442/20; Y10T442/2033; Y10T442/30; Y10T442/3472; Y10T442/3602; Y10T442/3699
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
20 words
A sheet of fibrous material as in claim 1 wherein said polymeric precursor is partially cured to a polyimide resin.
Claim 2
Dependent Claim
53 words
A sheet of fibrous material impregnated with a partially cured polymeric Precursor of a polyimide resin, such precursor having from about 3 percent to about 12 percent by weight, based on the combined weight of the anhydride component and the amine component of the precursor, of inert, thermally stable, colloidal particles dispersed therein.
Claim 3
Dependent Claim
18 words
A sheet of fibrous material as in claim 3 wherein said inert, thermally stable, colloidal particles are silica.
Claim 4
Dependent Claim
34 words
A sheet of fibrous material as in claim 3 wherein said polymeric precursor is the reaction product of benzophenonetetracarboxylic acid dianhydride and metaphenylene diamine and said inert, thermally stable, colloidal particles are colloidal silica.
Claim 5
Dependent Claim
20 words
A sheet of fibrous material as in claim 1 wherein said polymeric precursor is fully cured to a polyimide resin.
Claim 6
Dependent Claim
94 words
A reinforced resinous laminate having low void content, comprising a plurality of plies of fibrous sheet material impregnated with a polyimide resin, such resin having from about 0.5 percent to about 20 percent by weight, based on the combined weight of the anhydride component and the amine component of the resin, of inert, thermally stable, colloidal particles dispersed therein, said particles being selected from the group consisting of polyimide molding powder, barium titanate, potassium titanate, magnesium sulfate, asbestos, magnetic iron oxide, potassium sodium tartrate, ammonium dihydrogen phosphate, nonabrasive amorphous alumina, and nonabrasive amorphous silica.
Claim 7
Dependent Claim
29 words
A laminate as in claim 7 wherein said inert, thermally stable colloidal particles are present in an amount in the range from about 3 percent to about 12 percent.
Claim 8
Dependent Claim
25 words
A laminate as in claim 7 wherein said inert, thermally stable colloidal particles are present in an amount of about 7 percent to 8 percent.
Claim 9
Dependent Claim
15 words
A laminate as in claim 7 wherein said inert, thermally stable particles are colloidal silica.
Claim 10
Dependent Claim
15 words
A laminate as in claim 8 wherein said inert, thermally stable particles are colloidal silica.
Claim 11
Dependent Claim
15 words
A laminate as in claim 9 wherein said inert, thermally stable particles are colloidal silica.
Claim 12
Dependent Claim
19 words
A laminate as in claim 7 wherein said polyimide resin is formed from a polymeric precursor having the formula:
Claim 13
Dependent Claim
51 words
A laminate as in claim 7 wherein said polyimide resin is formed from a polymeric precursor that is the reaction product of an aromatic primary diamine containing from six to 16 carbon atoms with the dianhydride of an acid selected from the group consisting of 2,2'',3,3''-, 2,3,3'',4''-3,3'',4,4''-benzophenonetetracarboxylic acids and mixtures thereof.
Claim 14
Dependent Claim
68 words
A laminate as in claim 7 wherein said polyimide resin is formed from a polymeric precursor that is formed by reaction of primary aromatic diamines with an acyl halide derivative of trimellitic anhydride with at least one acyl halide group at the 4-position of the ring until a polymer with film forming properties is formed that has an inherent viscosity of at least 0.2 when dissolved in N,N-dimethylacetamide.
Claim 15
Dependent Claim
19 words
A laminate as in claim 7 wherein said polyimide resin is formed from a polymeric precursor having the formula:
Claim 16
Dependent Claim
64 words
A reinforced resinous laminate having low void content, comprising a plurality of plies of fibrous sheet material impregnated with a polyimide resin, such resin being the reaction product of benzophenonetetracarboxylic acid dianhydride and metaphenylene diamine, and having from about 0.5 percent to about 20 percent by weight, based on the combined weight of the benzophenonetetracarboxylic acid dianhydride and the metaphenylene diamine, of colloidal silica.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-10-25 | 1975-04-26 | 1975-10-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-10-25 | 1979-04-26 | 1979-10-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-10-25 | 1983-04-26 | 1983-10-26 | $7700.00 | Window Closed / Lapsed |