EP0048315A2
Expired / Lapsed
EP
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Process for preparing high temperature polyimide film laminates
Assignee: National Aeronautics and Space Administration
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Filing: 1981-05-07
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Granted: —
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Expires: 2001-05-07
Abstract
Abstract A process for fabricating large area void-free polyimide laminate structures wherein multiple ply polyimide film laminates may be constructed without decreasing the individual film strength and wherein layers of metal foil may be laminated between polyimide film layers to yield a flexible high temperature resistant structure having capabilities for use as flexible electric circuits in aerospace applications and the like.
Inventors
- 👤 Anne King St. Clair
- 👤 Terry Lee St. Clair
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 16:11
CPC Classifications
B; B32; B32B; B32B27/00; B32B27/34; B32B15/00; B32B15/04; B32B15/08; B32B7/00; B32B7/04; B32B7/12; H; H05; H05K; H05K3/00; H05K3/38; H05K3/386; B32B2457/00; H05K1/00; H05K1/02; H05K1/03; H05K1/0393; H05K2201/00; H05K2201/01; H05K2201/0137; H05K2201/0154; H05K2201/03; H05K2201/0332; H05K2201/0335; H05K2201/0355; H05K2203/00; H05K2203/07; H05K2203/0756; H05K2203/0759
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
72 words
A process for preparing high temperature resistant polyimide film comprising the steps of: providing at least two layers of a thin polyimide film; providing at least one layer of polyimide adhesive on one of said at least two layers of polyimide film; assembling said two layers of polyimide film to form a sandwich; and subjecting the film-adhesive sandwich to heat and pressure to thermoplastically bond the sandwich into a void-free laminate structure.
Claim 2
Dependent Claim
72 words
A process for preparing high temperature resistant polyimide film comprising the steps of: providing at least two layers of a thin polyimide film; providing at least one layer of polyimide adhesive on one of said at least two layers of polyimide film; assembling said two layers of polyimide film to form a sandwich; and subjecting the film-adhesive sandwich to heat and pressure to thermoplastically bond the sandwich into a void-free laminate structure.
Claim 3
Dependent Claim
64 words
The process of claim 1 wherein the polyimide adhesive is in liquid form and is brush coated on only one layer of polyimide film and this coated layer is heated to an elevated temperature to B-stage the adhesive layer prior to assembly of the sandwich, or a film of polyimide adhesive is prepared and B-staged prior to being used to bond the polyimide film.
Claim 4
Dependent Claim
33 words
The method of claim 1 wherein the polyimide film layers are selected from the group consisting of polyimides formed as the reaction product of (a) PMDA and ODA and (b) BTDA and ODA.
Claim 5
Dependent Claim
38 words
The process of claim 1 wherein a layer of conductive metal film is also provided between each two layers of polyimide film and a layer of polyimide adhesive is provided adjacent each surface of the metal film layer.
Claim 6
Dependent Claim
41 words
The process of claim 4 including: assembling the polyimide film, metal foil and adhesive so as to give a film-adhesive-metal-adhesive-film sandwich; and subjecting the sandwich assembly to heat and pressure to thermally bond the sandwiched assembly into a void-free laminate strucutre.
Claim 7
Dependent Claim
43 words
The process of claim 4 or claim 5 wherein the metal film layer is selected from the group consisting of aluminum, brass, copper and stainless steel and each member of the group being in the thickness range of 1 mil and 30 mil.
Claim 8
Dependent Claim
44 words
The process of claim 5 wherein the polyimide adhesive is applied to the laminate surfaces in liquid form and consists of a polyamic acid dissolved in a' solvent or the polyimide adhesive is a thin film of a polyimide that has been previously B-staged.
Claim 9
Dependent Claim
57 words
The process of claim 1 or 5 wherein the polyimide adhesive is a linear polyamic acid adhesive solution selected from the group consisting of: (a) BTDA and 3,3'-DABP; (b) two parts BTDA to one part PMDA and 3,3'-DABP; and (c) three parts BTDA to one part PMDA and 4,4'-DABP, each group member being dissolved in a solvent.
Claim 10
Dependent Claim
33 words
The process of claim 8 wherein the adhesive solid concentration is approximately 15% and the solvent is selected from the group consisting on N,N-dimethylacetamide, bis(2-methoxyethyl)ether, N,N-dimethylformanide, N-methyl-2-pyrrolidone, dimethylsulfoxide, tetrahydrofuran, m-dioxane, p-dioxane and 1,2-bis(2-methoxyethoxy)ethane.
Claim 11
Dependent Claim
54 words
The process of claim 8 wherein the solvent is N,N'-dimethylacetamide and the adhesive is B-staged prior to lamination or the solvent is bis(2-methoxyethyl)-ether and the adhesive is B-staged by applying a thin coat of the liquid adhesive onto a smooth surface and heating in air sufficiently to recover a thin film of polyimide adhesive.
References Cited (Backward Citations)
No citation records indexed.
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