▎ 摘　　要

NOVELTY - Polyimide composite film comprises an ion-doped polyimide layer and a graphene-modified polyimide layer. A filter layer is disposed between the ion-doped polyimide layer and the graphene-modified polyimide layer and an optical bond is disposed under the graphene-modified polyimide layer. USE - The film is useful for flexible display (claimed). ADVANTAGE - The film improves stress problem of the flexible display substrate and has good electrical and thermal conductivity and antistatic performance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for preparing polyimide composite film, comprising (i) preparing graphene modified polyimide layer, (ii) forming a filter layer on a surface of one side of the graphene-modified polyimide layer, (iii) forming an optical adhesive layer on the other side surface of the graphene-modified polyimide layer, (iv) forming a polyimide layer on the other side surface of the filter layer, and (v) injecting ions into the surface of the polyimide layer by an ion implantation method.