What are the characteristics of the hierarchical structure of the FPC film key switch

What is the characteristic of the hierarchical structure of the FPC film key switch? The film switch is a set of key functions, indicators, instrument panel as one of the operating systems. The utility model is composed of a panel, an upper circuit, an isolation layer and a lower circuit. Normally, the upper and lower contacts of the membrane switch are in the open state. The following film switch manufacturers introduced the layered structure of the film switch: Film switch has a good waterproof, dustproof, anti-oil, anti-erosion of harmful gases, stable and reliable performance, light weight, small size, long service life, easy installation and connection, no damage to the face plate cleaning, etc. , colorful and beautiful. 1. A transparent sheet of less than 0.25 mm in size, such as pet or PC, usually made of colorless transparent sheet material, the choice of materials must have high transparency, high ink adhesion, high elasticity, folding resistance and so on. 2. The main function of the buffer layer is to connect the panel layer with the circuit layer to achieve the effect of sealing connection. The thickness of this layer should be 0.02-0.05 mm, with high viscosity and anti-aging properties. Special double-sided plastic film switches are usually used. Some membrane switches require waterproof and high-temperature performance, so the gasket must also be used according to different properties of the material. 3. The upper and lower layers of the control circuit adopt the good performance pet as the carrier of the switch circuit, the upper layers print silver paste or gold paste, and the silver paste has the conductivity with the special process wire. Silver paste is generally 0.05-0.175 mm thick, with the most common being 0.125 mm for pets. 4. The middle layer is located between the upper and lower line layers and acts as a sealing joint. The thickness of 0.050.2 mm pet double-sided adhesive is usually used. In the choice of Laminates, should take full account of the overall thickness of the product and insulation, feel and key circuit packaging sealing. 5. The use of back glue layer and back glue film switch is closely related to adhesive material, common double-sided Glue, 3m Glue, waterproof glue, etc. .