A coating machine uses a high vacuum to melt, evaporate, and deposit high-purity zinc and aluminum on the base film. After an incredibly thin metal layer has been created, a metalized polypropylene film is created on the surface.
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 actual fabrication of capacitors.
