| 摘要 |
PURPOSE:To acquire a substrate for a flexible printed circuit without lowering alkali resistance, solvent resistance, heat resistance and electric characteristics by using a polyimide film with semi-cured polyamic acid layer on a surface having an opening part as a supporting film. CONSTITUTION:A method for forming a semi-cured polyamic oxide film on a polyimide film can be acquired by applying polyamic acid solution on the polyimide film by making it flow wide to a uniform thickness of 1 to 100mum by a known application means such as a rotary coater, and by heating and drying it thereafter. Boring process to the polyimide film with a polyamic acid layer is carried out together with a polyimide film by a usual method such as punching and cutting. After a polyamic acid surface of the polyimid film with polyamic acid layer wherein boring is finished is laminated on a conductor foil or a flexible printed circuit substrate, heated and bonded, it is imided fully. |
