US4898753A
Expired / Lapsed
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Process for the preparation of aromatic polyimide film
Assignee: Ube Corp
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Filing: 1988-05-26
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Granted: 1990-02-06
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Expires: 2008-05-26
Abstract
Abstract A process for the preparation of an aromatic polyimide film having a surface provided with extremely small sized protrusions having an average diameter of 40 to 2,000 angstroms, the number of protrusions being in the range of 1x104 to 1x109/mm2 is disclosed. The process comprises the steps of coating a coating composition (aromatic polyamic acid solution containing inorganic particles having an average diameter of not larger than 1,000 angstroms) on at least one surface of an aromatic polyimide gel film containing a volatile material in an amount of 10 to 90 wt. % (aromatic polyimide gel film has been obtained by ring closure and imidation of an aromatic polyamic acid in an organic polar oslvent containing a dehydrating agent and a catalyst at a temperature of not higher than 200 DEG C.); drying the obtained film composite at a temperature of 50 DEG to 200 DEG C.; and subjecting the film composite to a heat treatment including heating at a temperature of not lower than 300 DEG C.
Inventors
- 👤 Hiroshi Inoue
- 👤 Tadao Muramatsu
- 👤 Yasuji Narahara
- 👤 Tetsuji Hirano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:17
CPC Classifications
C; C09; C09D; C09D179/00; C09D179/04; C09D179/08; C08; C08J; C08J7/00; C08J7/04; C08J7/0427; G; G11; G11B; G11B5/00; G11B5/62; G11B5/73; G11B5/739; G11B5/73923; G11B5/73925; G11B5/73937; G11B5/74; C08J2379/00; C08J2379/04; C08J2379/08; C08J2479/00; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
182 words
A process for the preparation of an aromatic polyimide film having a surface provided with protrusions having an average diameter of 40 to 2,000 angstroms, the number of protrusions being in the range of 1×10 4 to 1×10 9 /mm 2 , which comprises the steps of coating an aromatic polyamic acid solution containing inorganic particles having an average diameter of not larger than 1,000 angstroms on at least one surface of an aromatic polyimide gel film containing a volatile material in an amount of 10 to 90 wt. %, said aromatic polyimide gel film having been obtained by ring closure and imidation of an aromatic polyamic acid in an organic polar solvent containing a dehydrating agent and a catalyst at a temperature of not higher than 200° C. to form a composite of said gel film having a coated surface containing said inorganic particles; drying said film composite at a temperature of 50° to 200° C.; and heat treating the dried film composite at a temperature of not lower than 300° C. to form said polyimide film having said surface protrusions.
Claim 2
Dependent Claim
182 words
A process for the preparation of an aromatic polyimide film having a surface provided with protrusions having an average diameter of 40 to 2,000 angstroms, the number of protrusions being in the range of 1×10 4 to 1×10 9 /mm 2 , which comprises the steps of coating an aromatic polyamic acid solution containing inorganic particles having an average diameter of not larger than 1,000 angstroms on at least one surface of an aromatic polyimide gel film containing a volatile material in an amount of 10 to 90 wt. %, said aromatic polyimide gel film having been obtained by ring closure and imidation of an aromatic polyamic acid in an organic polar solvent containing a dehydrating agent and a catalyst at a temperature of not higher than 200° C. to form a composite of said gel film having a coated surface containing said inorganic particles; drying said film composite at a temperature of 50° to 200° C.; and heat treating the dried film composite at a temperature of not lower than 300° C. to form said polyimide film having said surface protrusions.
Claim 3
Dependent Claim
31 words
The process as claimed in claim 1, wherein said aromatic polyamic acid is obtained by polymerizing an aromatic diamine component and an aromatic tetracarboxylic acid component in an organic polar solvent.
Claim 4
Dependent Claim
16 words
The process as claimed in claim 1, wherein said dehydrating agent is an organic acid anhydride.
Claim 5
Dependent Claim
15 words
The process as claimed in claim 3, wherein said organic acid anhydride is acetic anhydride.
Claim 6
Dependent Claim
14 words
The process as claimed in claim 1, wherein said catalyst is a tertiary amine.
Claim 7
Dependent Claim
13 words
The process as claimed in claim 5, wherein said tertiary amine is isoquinoline.
Claim 8
Dependent Claim
24 words
The process as claimed in claim 1, wherein said inorganic particles are inert inorganic particles having an average diameter of 40 to 1,000 angstroms.
Claim 9
Dependent Claim
14 words
The process as claimed in claim 7, wherein said inorganic particles are colloidal silica.
Claim 10
Dependent Claim
29 words
The process as claimed in claim 1, wherein said aromatic polyamic acid solution for the coating contains the inorganic particles in an amount of 0.001 to 10.0 wt. %.
Claim 11
Dependent Claim
41 words
The process as claimed in claim 1, wherein said aromatic polyamic acid solution is coated on the surface of the aromatic polyimide gel film in an amount of 0.5 to 35 wt. % of the gel film on a dry basis.
Claim 12
Dependent Claim
34 words
The process as claimed in claim 1, wherein the protrusions on the surface of the aromatic polyimide film prepared by the process has a maximum height in the range of 50 to 500 angstroms.
Claim 13
Dependent Claim
39 words
The process as claimed in claim 2, wherein said aromatic polyimide gel film contains said volatile material in an amount of 20 to 85 wt. % and said inorganic particles have an average diameter of 100 to 800 angstroms.
Claim 14
Dependent Claim
63 words
The process as claimed in claim 2, wherein said aromatic polyamic acid solution for the coating contains the inorganic particles in an amount of 0.01 to 6 wt. % and said aromatic polyamic acid solution is coated on the surface of the aromatic polyimide gel film in an amount of 1 to 30 wt. % of the gel film on a dry basis.
Claim 15
Dependent Claim
37 words
The process as claimed in claim 2, wherein said protrusions have an average diameter of 60 to 1,800 angstroms and the number of protrusions is in the range of 5×10 5 to 5×10 8 /mm 2 .
Claim 16
Dependent Claim
63 words
The process as claimed in claim 12, wherein said aromatic polyamic acid solution for the coating contains the inorganic particles in an amount of 0.01 to 6 wt. % and said aromatic polyamic acid solution is coated on the surface of the aromatic polyimide gel film in an amount of 1 to 30 wt. % of the gel film on a dry basis.
Claim 17
Dependent Claim
37 words
The process as claimed in claim 12, wherein said protrusions have an average diameter of 60 to 1,800 angstroms and the number of protrusions is in the range of 5×10 5 to 5×10 8 /mm 2 .
Claim 18
Dependent Claim
37 words
The process as claimed in claim 13, wherein said protrusions have an average diameter of 60 to 1,800 angstroms and the number of protrusions is in the range of 5×10 5 to 5×10 8 /mm 2 .
Claim 19
Dependent Claim
37 words
The process as claimed in claim 15, wherein said protrusions have an average diameter of 60 to 1,800 angstroms and the number of protrusions is in the range of 5×10 5 to 5×10 8 /mm 2 .
Claim 20
Dependent Claim
14 words
The process as claimed in claim 12, wherein said inorganic particles are colloidal silica.
Claim 21
Dependent Claim
14 words
The process as claimed in claim 13, wherein said inorganic particles are colloidal silica.
Claim 22
Dependent Claim
14 words
The process as claimed in claim 14, wherein said inorganic particles are colloidal silica.
Claim 23
Dependent Claim
14 words
The process as claimed in claim 15, wherein said inorganic particles are colloidal silica.
Claim 24
Dependent Claim
14 words
The process as claimed in claim 16, wherein said inorganic particles are colloidal silica.
Claim 25
Dependent Claim
14 words
The process as claimed in claim 17, wherein said inorganic particles are colloidal silica.
Claim 26
Dependent Claim
14 words
The process as claimed in claim 18, wherein said inorganic particles are colloidal silica.
References Cited (Backward Citations)
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