| 摘要 |
PURPOSE:To stably obtain the titled dope readily processable into films, by reacting an aromatic dicarboxylic acid with aromatic diisocyanate in respective specific amounts in the presence of a tertiary amine and alkali (earth) group halide in specific amounts in an aprotic organic polar solvent. CONSTITUTION:An aromatic dicarboxylic acid expressed by formula I (Preferably terephthalic acid) and an aromatic diisocyanate expressed by formula II [R1 and R2 are group expressed by formula III-V (X is halogen; l, m and n are 0-4; p is 0-3; Y is -CH2-; r is 0 or 1] (preferably diphenylmethane-4,4'- diisocyanate) are reacted in an aprotic organic polar solvent (e.g. N-methyl-2- pyrrolidone) in the presence of a tertiary amine (preferably triethylamine) in an amount of 1-300mol.% based on the number of mol. of the monomer and an alkali (earth) group halide (e.g. lithium chloride) in an amount of 3-200wt.% based on the polymer to readily provide a high molecular weight without emitting hydrogen halides and afford the aimed dope suitable as a base film for heat-sensitive transfer.
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