| abstract |
PROBLEM TO BE SOLVED: To provide a high-definition pattern, high adhesion between a wiring pattern layer and a substrate, excellent insulation performance between wiring pattern layers, easy connection, and warpage. Provide a multilayer printed wiring board that can prevent occurrence. The substrate includes a substrate and a plurality of wiring pattern layers transferred onto the substrate, the wiring pattern layer being a conductive layer and an insulating resin layer formed below the conductive layer and containing a block polyimide copolymer. And a heat treatment at 450 to 500 ° C. for 1 hour or more. |