| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polybenzoxazole resin which is excellent in electrical properties and heat resistance and has low water absorption properties by subjecting a polybenzoxazole precursor having specific repeating units to cyclodehydration. SOLUTION: The objective polybenzoxazole resin is obtained by subjecting a polybenzoxazole precursor represented by formula I to cyclodehydration. The precursor is prepared by condensing a dicarboxylic acid represented by formula II (e.g. terephthalic acid) with a bisaminophenol compound represented by formula II (e.g. 4,4'-diamino-3,3-dihydroxybiphenyl) in the presence of a dehydration-condensation agent (e.g. polyphosphoric acid). In the formulas, n is 1-1,000; R1 to R4 are each fluoroalkyl; R10 to R12 are each H, trifluoromethyl or the like; m is 1-10; Y is a single bond or an at least divalent organic group; and X is a divalent organic group represented by formula IV (wherein R5 to R10 are each F or fluoroalkyl; Z is O or a single bond; i is 1-6; and j is 0-6).
|
