Title:
POLYIMIDE POWDER, POLYIMIDE VARNISH AND POLYIMIDE FILM
Document Type and Number:
WIPO Patent Application WO/2019/065136
Kind Code:
A1
Abstract:
A polyimide powder which is composed of a blend of a polyimide powder A and a polyimide powder B and is soluble in an organic solvent, and which is characterized in that: the polyimide powder A and the polyimide powder B are composed of polyimides which have a structural unit that is derived from at least one aromatic diamine compound and a structural unit that is derived from at least one tetracarboxylic acid dianhydride; the polyimide powder A is composed of a polyimide which has (a-1) a reduced viscosity of 1.2 dL/g or more but less than 2.1 dL/g or (a-2) a weight average molecular weight of 100,000 g/mol or more but less than 250,000 g/mol; the polyimide powder B is composed of a polyimide which has (b-1) a reduced viscosity of from 2.1 dL/g to 3.0 dL/g (inclusive) or (b-2) a weight average molecular weight of from 250,000 g/mol to 500,000 g/mol (inclusive); the weight ratio of the polyimide powder A to the polyimide powder B is within the range of from 10/90 to 90/10; and a blend of the polyimide powder A and the polyimide powder B has a reduced viscosity within the range of from 1.7 dL/g to 2.5 dL/g, or a blend of the polyimide powder A and the polyimide powder B has a weight average molecular weight within the range of from 160,000 g/mol to 350,000 g/mol. This polyimide powder is soluble in an organic solvent, while having excellent handling properties. A varnish which is obtained by dissolving this polyimide powder into an organic solvent at a predetermined concentration forms a polyimide film that exhibits excellent heat resistance, transparency and mechanical characteristics.
Inventors:
TANAKA KEIZO (JP)
YAMADA SHUNSUKE (JP)
NAGASHIMA YUTAKA (JP)
SHIMIZU SEIGO (JP)
YAMADA SHUNSUKE (JP)
NAGASHIMA YUTAKA (JP)
SHIMIZU SEIGO (JP)
Application Number:
PCT/JP2018/032955
Publication Date:
April 04, 2019
Filing Date:
September 06, 2018
Export Citation:
Assignee:
KAWAMURA SANGYO CO LTD (JP)
International Classes:
C08L79/08; C08G73/10; C08J5/18
Domestic Patent References:
| WO2011055530A1 | 2011-05-12 | |||
| WO2013111836A1 | 2013-08-01 | |||
| WO2017179367A1 | 2017-10-19 |
Foreign References:
| JPH03243629A | 1991-10-30 | |||
| JP2013523939A | 2013-06-17 | |||
| JP2005524753A | 2005-08-18 |
Attorney, Agent or Firm:
TSUKUNI & ASSOCIATES et al. (JP)
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