| 摘要 |
PROBLEM TO BE SOLVED: To provide a multilayered polyimide film enhanced in tensile breaking strength and tensile elastic modulus, having the coefficient of linear expansion within a specific low range and improved in surface characteristics. SOLUTION: The multilayered polyimide film is obtained by laminating a layer (a) comprising a polyamideimide and a layer (b) comprising a polyimide, which has at least a pyromellitic acid residue as a residue of an aromatic tetracarboxylic acid and a diamine residue having a benzooxazole skeleton as a residue of an aromatic diamine, and characterized in that the thickness ratio (a)/(b) of the layers (a) and (b) is 0.001-0.5 and the thickness of the layer (b) is 3-50μm. The coefficient of linear expansion in the surface direction of the multilayered polyimide film is 0-10 ppm/°C and the tensile breaking strength thereof is 300 MPa or above and the tensile elastic modulus thereof is 5 GPa or above. COPYRIGHT: (C)2007,JPO&INPIT
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