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Amphiphilic polyimide precursor and process for preparing the same from fatty-substituted polyamide-acids

Assignee: Kanegafuchi Chemical Industry Co Ltd
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Filing: 1989-09-07
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Granted: 1991-01-29
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Expires: 2009-09-07
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Abstract

Abstract An amphiphilic polyimide precursor having at least 70% by mole of the recurring unit of the formula (1): ##STR1## wherein R 1 is a tetravalent group having at least 2 carbon atoms, R 2 is a bivalent group having at least 2 carbon atoms, and R 3 , R 4 , R 5 and R 6 are hydrogen atom or a monovalent group having 1 to 30 carbon atoms selected from an aliphatic group, an alicyclic group, an aromatic group, a group in which an aliphatic group is combined with an alicyclic group or an aromatic group, and their groups substituted by a halogen atom, nitro group, amino group, cyano group, methoxy group or acetoxyl group, provided that at least one, preferably at least two, of R 3 , R 4 , R 5 and R 6 are hydrobolic monomolecular group 12 to 30 carbon atoms, the polyimide precursor being able to form a built-up film on substrates according to the Langmuir-Blodgett technique and being able to be converted into polyimide by heat treatment to provide an ultrathin film of polyimide having a thickness of not more than 10,000 Å and excellent heat resistance, chemical resistance, mechanical property and electric characteristics.

Inventors

  • 👤 Masakazu Uekita
  • 👤 Hiroshi Awaji

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 15:56
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 44 words
A film comprising at least one monomolecular layer of a polyimide having recurring units of the formula ##STR40## wherein R 1 is a tetravalent group having at least 2 carbon atoms, and R 2 is a bivalent group having at least 2 carbon atoms.
Claim 2
Dependent Claim 44 words
A film comprising at least one monomolecular layer of a polyimide having recurring units of the formula ##STR40## wherein R 1 is a tetravalent group having at least 2 carbon atoms, and R 2 is a bivalent group having at least 2 carbon atoms.
Claim 3
Dependent Claim 17 words
The film of claim 1, which has a dielectric strength of not less than 1×10 6 V/cm.
Claim 4
Dependent Claim 15 words
The film of claim 1, which has a thickness of not more than 1,000 Å.
Claim 5
Dependent Claim 16 words
The film of claim 1, which has a heat resistance of not lower than 400° C.
Claim 6
Dependent Claim 35 words
The film of claim 1, which has a thickness of not more than 1,000 Å, a dielectric strength of not less than 1×10 6 V/cm, and a heat resistance of not lower than 400° C.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1994-01-28 1994-07-30 1995-01-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1998-01-28 1998-07-30 1999-01-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2002-01-28 2002-07-30 2003-01-29 $7700.00 Window Closed / Lapsed

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