| 摘要 |
<p>PURPOSE:To obtain the title film comprising a polyimide film soluble in an organic solvent and, formed thereon, another polyimide film and having low permittivity and excellent transparency by forming the upper-layer film after the soluble polyimide film is heat-treated at a specified temperature. CONSTITUTION:A process for producing a multilayer polyimide film by forming a polyimide film on another polyimide film soluble in an organic solvent, wherein a polyimide film (e.g. one produced from 2,2'-bis(trifluoromethyl)-4,4'- diaminobiphenyl and 2,2-bis(3,4-dicarboxyphenyl)-hexafluoropropane dianhydride) soluble in an organic solvent (e.g. N,N-dimethylacetamide) is heat-treated at 380 deg.C or above before another polyimide film is formed thereon.</p> |
