| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an essentially colorless, transparent polyimide film useful for optical fibers and thermal protective coatings. <P>SOLUTION: The polyimide film comprises preparing a polyamic acid solution by reacting an acid component with a diamine component in an organic polar solvent, in which an aromatic tetracarboxylic acid dianhydride, which is represented by chemical formula (1), is used as the acid component, and bis[4-aminophenyl]sulfone and >10% of a second para- or meta-substituted diamine monomer with respect to the total weight of the diamine monomer, which is represented by chemical formula (2), is used as the diamine component, wherein the second para- or meta-substituted diamine monomer is bis[4-(3-aminophenoxy)phenyl]sulfone (BAPSM), bis[4-(4-aminophenoxy)phenyl]sulfone (BAPS), methylene dianiline (MDA), or 2,2'-bis[4-(4-aminophenoxy)phenyl]propane (BAPP), and forming a film prepared from the polyamic acid solution, wherein a yellowness index measured by ASTM D1925 is <10. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
