| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to form a film, which is excellent in painting and is excellent in chemical resistance and heat resistance, by a method wherein a composition containing a polyimide, which is soluble in an organic solvent as insulating layers and has a carboxylic acid group or an amino group, and an epoxy compound, which can be reacted with this polyimide, as its essential components is used for the insulating layers. SOLUTION: A crosslinked structure which is constituted from the reaction of a polyimide, which is soluble in an organic solvent as insulating layers and has a functional group which can form crosslinking, with a crosslinking agent is formed. The polyimide, which is soluble in the organic solvent, is obtained by reacting a tetracarboxylic acid dianhydride with a polyamine on a condition that the molar ratio of the tetracarboxylic acid dianhydride to the polyamine is within the range of 1.43>r>1.02 or 0.98>r>0.70. A crosslinking agent is added to the obtained polyimide solution as it is and the polyimide solution added to crosslinking agent can be used as a heat-resistant resin composition solution. One, which is preferable as the crosslinking agent, is an epoxy compound having more than two of epoxy groups in one molecule. As a result, a good painting workability of a composition, which is used for the insulating layers, is obtained. |
