Metal film/aromatic polymide film laminate
AssigneeUbe Industries, Ltd.
InventorsHiroaki Yamaguchi, Fumio Aoki
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Abstract
A metal film, particularly, a stainless steel film having been not subjected to roughing treatment, and an aromatic polyimide substrate film having a thermoplastic surface can be combined with a high bonding strength to form a metal film/aromatic polyimide film laminate, utilizing an amorphous aromatic polyimide film of 0.05 to 3 μm thick which has a glass transition temperature in the range of 200 to 300° C.
Claims9
A metal film/aromatic polyimide films/metal film laminate comprising a first metal film, an amorphous aromatic polyimide film of 0.05 to 3 μm thick which has a glass transition temperature in the range of 200 to 300° C., an aromatic polyimide substrate film, and a second metal film in order, the second metal film being a copper film having been subjected to surface roughing treatment, the substrate film having a thickness of 10 to 150 μm and a linear expansion coefficient of not higher than 30×10−6 cm/cm/° C. in the temperature range of 50 to 200° C., and comprising a non-thermoplastic polyimide base layer and a pair of thermoplastic polyimide layers each of which is fixed onto each surface of the base layer.
A process for preparing a metal film/aromatic polyimide film/metal film laminate which comprises the steps of:
- coating on one surface of a first metal film a solution of a polyimide precursor which is produced from a combination of one or more of the following tetracarboxylic dianhydrides and one or more of the following diamine compounds:
- (1) 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,3,3′,4′-biphenyltetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride and bis(3,4-dicarboxyphenyl)ether dianhydride and (2) 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 2,2-bis(4-aminophenoxyphenyl)propane, 4,4′-bis(4-aminophenoxyphenyl)sulfone and bis(4-aminophenoxy)biphenyl, to form a coated solution film on the metal film;
- heating the coated solution film to produce an amorphous polyimide film on the metal film;
- placing a second metal film and an aromatic polyimide substrate film having a thermoplastic surface on each surface thereof onto the amorphous polyimide film on the metal film, so as to form a film structure of the second metal film, the aromatic polyimide substrate film, the amorphous film, and the first metal film, in order;
- and
- pressing the film structure under heating to fix each film onto an adjoining film thereof.
Dependencies are inferred from the claim text.