Commonly used materials for making membrane switch

-The material selection of the membrane switch  is very important, among which polyvinyl chloride (PVC) is common. PVC is used at 60 ° C, the thickness range is 0.175~0.5 mm, and the surface is smooth. It has good stability to acid, alkali and salt at room temperature, good wear resistance, fire resistance and noise damping effect. Good electrical insulation, but relatively poor thermal stability. Suitable for the production of ordinary signs and panels, low price.

-Another common material is polycarbonate (PC). The operating temperature range of PC is -60~120℃, and the thickness is between 0.175~1.0 mm. It has high light transmittance, low water absorption and excellent dimensional stability. PC bending, tensile, compressive strength is outstanding, excellent heat and cold resistance, electrical insulation and aging resistance is also very good. However, its drug resistance and fatigue resistance are poor, and it is easy to crack due to stress. The output interface terminal circuit is usually printed with carbon material, without protective coating, which may be shed due to air oxidation, resulting in a break, and the service life is generally 3-10 years. PC has a wide range of applications, especially the high light transmission of the smooth PC is suitable for devices with liquid crystal display Windows.

-Sand-faced polyester (PET) is another option, operating at -30 to 120 ° C. The thickness of PET is generally 0.1-0.2 mm, and it is treated with smooth surface. It has excellent drug resistance, insoluble in most organic solvents, and is not alkali resistant. PET has excellent mechanical properties, especially high strength and toughness, low water absorption, wear and friction resistance. The tensile strength is even comparable to that of aluminum film. Although the price is relatively low, because the surface treatment is more difficult, the price of textured PET is higher, which is suitable for products with high surface texture requirements or need liquid crystal display Windows.

-Membrane switch  is an operating system which integrates key function, indicator element and instrument panel. It consists of four parts: panel, upper circuit, isolation layer and lower circuit. It is a normally open switch with light touch connection. Under normal circumstances, the upper and lower contacts of the membrane switch  are disconnected. Press the membrane switch , the contact of the upper circuit deforms downward, and the plate of the lower circuit contacts through. After the finger is loosened, the contact of the upper circuit rebounds back, the circuit is disconnected, and the circuit triggers a signal. Thin membrane switch structure is rigorous, beautiful appearance, good sealing. It has the characteristics of moisture-proof and long service life. Widely used in electronic communication, electronic measurement instruments, industrial control, medical equipment, automotive industry, intelligent toys, household appliances and other fields.