EP0441013A1
Expired / Lapsed
EP
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Polyimide sheet and preparation process of the sheet
Assignee: Mitsui Toatsu Chemicals Inc
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Filing: 1990-02-05
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Granted: —
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Expires: 2010-02-05
Abstract
Abstract The polyimide sheets having excellent thermal resistance and good surface appearance of the resultant sheets is obtained by melt-extrusion process from specific polyimide in the temperature range of 300°C to 450 °C and controlling the moisture content to 200ppm or less in the polyimide used as raw materials .
Inventors
- 👤 Masumi Saruwatari
- 👤 Shinobu Moriya
- 👤 Schochi Tsuji
- 👤 Masahiro Ohta
- 👤 Masami Nakano
- 👤 Toshiyuki Nakakura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 01:46
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08G73/1071; B; B29; B29C; B29C48/00; B29C48/03; B29C48/07; B29C48/08; B29C48/25; B29C48/78; B29C48/80; B29C48/83; B29C48/832; C08G73/1046; C08G73/105; C08G73/1057; C08G73/1064; C08L; C08L79/00; C08L79/04; C08L79/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
89 words
A polyimide sheet comprising one or more of polyimide having recurring structural units represented by the formula( I ) wherein R is a tetravalent radical selected from the group consisting of an aliphatic radical having two or more carbon atoms, a cyclo-aliphatic radical, a monoaromatic radical, a condensed polyaromatic radical and a non-condensed polyaromatic radical wherein the aromatic radicals are mutually connected with a bond or a crosslinking function, X is a divalent radical of a single bond, sulfur atom, sulfonyl radical, carbonyl radical, isopropylidene radical, or hexafluoroisopropylidene radical.
Claim 2
Dependent Claim
17 words
The polyimide sheet of claim 1 wherein R in formula( I ) is a tetravalent radical of
Claim 3
Dependent Claim
17 words
The polyimide sheet of claim 1 or 2 wherein a polyimide sheet is prepared by the melt-extrusion.
Claim 4
Dependent Claim
31 words
The preparation process of the polyimide sheet of claim 1 or 2 comprising heat-melting in a temperature range of 300°C to 450 °C in melt-extrusion process and cooling the extruded sheet.
Claim 5
Dependent Claim
26 words
The preparation process of the polyimide sheet of claim 4 wherein the moisture content of polyimide used as raw materials is controlling to 200ppm or less.
References Cited (Backward Citations)
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