| abstract |
In the present invention, a copper foil is laminated on a heat-fusible polyimide layer of a heat-fusible polyimide film, and thermocompression bonding is performed to produce a copper foil laminate. The heat-fusible polyimide film comprises a heat-fusible polyimide layer and a heat-resistant polyimide layer. The polyimine which constitutes the heat-fusible polyimide layer is obtained from a tetracarboxylic acid component and a diamine component. The tetracarboxylic acid component contains 10 to 30 mol% of 3,3',4,4'-biphenyltetracarboxylic dianhydride, and contains 70 to 90 mol% of pyromellitic dianhydride. The diamine component contains more than 50 mole % of 2,2-bis[4-(4-aminophenoxy)phenyl]propane. The polyimine which constitutes the heat-resistant polyimide layer is obtained from a tetracarboxylic acid component and a diamine component. The tetracarboxylic acid component contains more than 50 mol% of 3,3',4,4'-biphenyltetracarboxylic dianhydride. The diamine component contains more than 50 mole % of p-phenylenediamine. |