DMD series insulating paper is a kind of non-woven soft composite material, the center is coated by polyester film with temperature resistant 155℃ adhesive, both sides are compounded by electrician’s non-woven fabric and become three-layer insulating paper, and the insulation grade belongs to class F. It has good dielectric strength and mechanical toughness, and is widely used in electrical equipment. It has good dielectric strength and mechanical toughness and is widely used in electrical equipment.