abstract |
The present invention provides a polyamic acid derivative capable of simultaneously imparting a very low residual stress and a high glass transition temperature as a coating film comprising a cured polyimide resin. A number average molecular weight containing unit unit 1 and unit unit 2 represented by the following general formula (1) is 3,000 to 100,000, and a polyimide resin after heat curing is −150 ° C. A polyamic acid derivative having a glass transition point in each of the region from 0 to 0 ° C and the region from 150 to 380 ° C. [Chemical 1] [Selection figure] No selection figure |