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EP0036330A1
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Process for continuously producing an aromatic polyimide film
Assignee: Ube Corp
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Filing: 1981-03-17
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Granted: —
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Expires: 2001-03-17
Abstract
Abstract An aromatic polyimide film having excellent mechanical, thermal and electrical properties, is continuously produced by the steps of: preparing a dope solution having a rotation viscosity of 500 -10 5 poises at 100°C by uniformly dissolving an aromatic polyimide in a solvent consisting of at least one phenol compound; extruding the dope solution through a T-die (1) at 50°C or more, but at least 30°C below the boiling point of the solvent, under conditions which cause the apparent viscosity and shear stress of the dope solution to be 500-5x10 4 poises and 10 4 - 106 dyne.cm- 2 , respectively, to form a filmy stream (10) of the dope solution; placing the filmy stream of the dope solution on a surface of a supporting means (7) while continuously moving it along its endless path, and; finally, solidifying the film of the dope solution by evaporating the solvent therefrom (8).
Inventors
- 👤 Yoshikazu C/O Hirakatajushi-Kenyusho Sasaki
- 👤 Hiroshi C/O Hirakatajushi-Kenyusho Inoue
- 👤 Youji Negi
- 👤 Kazuhiko Sakai
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 18:45
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
179 words
A process for continuously producing an aromatic polyimide film, comprising the steps of: preparing a dope solution in which an aromatic polyimide prepared from a biphenyl tetracarboxylic acid component and an aromatic diamine component, is uniformly dissolved in a solvent consisting of at least one phenol compound, and which exhibits a rotation viscosity of from 500 to 10 5 poises at a temperature of 100°C; extruding said dope solution under pressure through a slit of a T-die at an extrusion temperature of 50°C or more but at least 30°C below the boiling point of said solvent, while controlling the apparent viscosity and the shear stress of said dope solution to from 500 to 5 x 1 0 4 poises and from 1 0 4 to 1 0 6 dyne.cm- 2 , respectively, thereby forming a filmy stream of said dope solution; placing said extruded filmy stream of said dope solution on a surface of a supporting means while continuously moving it along an endless path thereof, and; solidifying the film of said dope solution by evaporating said solvent therefrom.
Claim 2
Dependent Claim
179 words
A process for continuously producing an aromatic polyimide film, comprising the steps of: preparing a dope solution in which an aromatic polyimide prepared from a biphenyl tetracarboxylic acid component and an aromatic diamine component, is uniformly dissolved in a solvent consisting of at least one phenol compound, and which exhibits a rotation viscosity of from 500 to 10 5 poises at a temperature of 100°C; extruding said dope solution under pressure through a slit of a T-die at an extrusion temperature of 50°C or more but at least 30°C below the boiling point of said solvent, while controlling the apparent viscosity and the shear stress of said dope solution to from 500 to 5 x 1 0 4 poises and from 1 0 4 to 1 0 6 dyne.cm- 2 , respectively, thereby forming a filmy stream of said dope solution; placing said extruded filmy stream of said dope solution on a surface of a supporting means while continuously moving it along an endless path thereof, and; solidifying the film of said dope solution by evaporating said solvent therefrom.
Claim 3
Dependent Claim
43 words
A process as claimed in claim 1, wherein said dope solution is prepared by polymerization and imide ring cyclization, in one single step, of said biphenyl tetracarboxylic compound with said aromatic diamine in said solvent, at a temperature of from 150 to 300°C.
Claim 4
Dependent Claim
44 words
A process as claimed in claim 1, wherein said biphenyl tetracarboxylic acid component contains 90 molar % or more of at least one member selected from the group consisting of 2,3,3',4'-biphenyl tetracarboxylic acid, 3,3',4,4'-biphenyl tetracarboxylic acid and their anhydrides, salts and lower alkyl esters.
Claim 5
Dependent Claim
63 words
A process as claimed in claim 3, wherein said biphenyl tetracarboxylic acid component additionally contains 10 molar % or less of at least one additional tetracarboxylic acid selected from the group consisting of pyromellitic acid, 2,3,6,7-naphthalene tetracarboxylic acid, 3,3',4,4'-benzophenone tetracarboxylic acid, 2,2-bis (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) ether, and butane tetracarboxylic acid, and anhydrides, salts and esters of the above-mentioned acids.
Claim 6
Dependent Claim
97 words
A process as claimed in claim 1, wherein said aromatic diamine component contains at least one member selected from the group consisting of those of the formulae (I) and (II): and wherein R 1 and R 2 respectively, independently from each other, represent a member selected from the group consisting of a hydrogen atom, lower alkyl radicals and lower alkoxy radicals, n represents an integer of from 1 to 4, and A represents a divalent radical selected from the group consisting of -0-, -S-, -CO-, -SO 2 -, -SO-, -CH - and -C(CH 3 ) 2 -.
Claim 7
Dependent Claim
67 words
A process as claimed in claim 1, wherein said phenol compound is selected from the group consisting of those of the formulae (III) and (IV): and wherein R 3 represents a member selected from the group consisting of a hydrogen atom and alkyl radicals having 1 to 3 carbon atoms, and X represents a member selected from the group consisting of a hydrogen atom and halogen atoms.
Claim 8
Dependent Claim
24 words
A process as claimed in claim 6, wherein said phenol compound is selected from the group consisting of phenol, monohalogenated phenols and monohalogenated cresols.
Claim 9
Dependent Claim
12 words
An aromatic polyimide film when made in accordance with any preceding claim.
References Cited (Backward Citations)
US4075171A
Cited
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