The base for MPET films is the 2um-12um polyester plain film. The standard width is 620mm.
High-purity zinc and aluminum are melted, evaporated, and deposited on the base film using a coating process under a strong vacuum. A metalized polypropylene film is then produced on top of the very thin metal layer.
After the partial breakdown of the film dielectric, the metalized film has a self-healing function that causes it to naturally revert to the electrical performance phenomenon before the breakdown. The metalized film is covered on one or both sides of the edge or in the center to create a blank insulating strip without evaporating metal, known as the margin, and its width is referred to as the margin in the
