Numerical control panel mainly used sand surface of polyester (PET): surface resistance of good character and insoluble in common organic solvents, alkaline not. With excellent mechanical properties, electrical properties, rigidity, hardness and thermal plastic plastic maximum strength and toughness, low water absorption, abrasion resistance, abrasion resistance excellent, high dimension stability. Tensile strength can comparable with the aluminum film, significantly higher than the PC, PVC low because the surface is difficult to be processed into a matte type, and therefore, texture pet more expensive is the production of membrane switch circuit the ideal substrate. The suitable for texture pet higher on the surface or with liquid crystal display window products