Types of FPC circuit membrane switch material
Time of issue：
1. Polyvinyl chloride PVC FPC circuit membrane switch material is stable to acids, alkalis and salts at room temperature, good abrasion resistance, flame resistance and self-extinguishing, silencing and shock absorption, and good electrical insulation. Poor thermal stability. Inexpensive ordinary sign, panel polycarbonate PC\-60~120℃\0.175~1.0\High light transmittance, low water absorption, good dimensional stability, excellent bending, tensile and compressive strength, heat resistance It has excellent cold resistance, electrical insulation and weather resistance. Poor chemical resistance, poor fatigue resistance, easy to cause stress to open the membrane switch and crack, the output interface terminal circuit is generally made of carbon material printing, and there is no protective coating, and it will gradually form a peeling layer due to air oxidation. Leading to open circuit and end of life, this is the most prone to failure of the membrane switch. It is mainly determined by the environment. No matter whether it is used or not, the physical damage time is 3-10 years. Generally, the scope of application is the widest. In addition to meeting the requirements of most membrane switch panels, the high light transmittance of glossy PC can also meet the requirements of LCD windows.
2. Sand surface polyester (PET) \-30~120℃\0.1~0.2 smooth FPC circuit membrane switch material has good chemical resistance, is insoluble in general organic solvents, and is not alkali resistant. It has excellent mechanical properties, electrical properties, rigidity, hardness and the greatest toughness among thermoplastics, low water absorption, excellent wear resistance and friction resistance, and high dimensional stability. The tensile strength is comparable to that of aluminum film, much higher than that of PC and PVC. Inexpensive Because the surface is difficult to process into a matte type, textured PET is more expensive and is the most ideal substrate for making membrane switch circuits. Among them, textured PET is suitable for products with higher surface requirements or liquid crystal display windows.
3. The thickness of the FPC circuit membrane switch material. The thickness of the plastic substrate is 0.25mm and below. It is called a film. It is mainly used as the panel layer of the membrane switch. Various indicative patterns and texts are printed on the back to indicate the corresponding switch position. The thickness of the operating area should be selected according to the size of the panel and the buttons. Thick materials will increase the touch force and slow response; if the material is too thin, the touch will be poor and the rebound will not be obvious. Thickness above 0.25mm is called sheet material, which is not suitable for three-dimensional key forming. It can be used as an indicative sign panel for the operation area without keys, and can also be used as a lining board for membrane switches to improve its hardness.
4. FPC circuit membrane switch circuit layer material The base material of the circuit should be made of polyester film. It has good insulation and heat resistance, high mechanical strength, transparency and air tightness, especially bending resistance and high elasticity. It is an ideal material for making FPC circuit membrane switch.