Common components of membrane switches

1. Panel layer

The panel layer is generally made by screen printing exquisite pictures and text on colorless transparent sheets such as PET and PC with a thickness of less than 0.25mm. As the primary function of the panel layer Z is to serve as a marker and button, it is necessary to select materials with high transparency, high ink adhesion, high elasticity, and anti folding properties.

2. Cushion layer

The primary function of the adhesive layer Z is to tightly connect the panel layer and the circuit layer to achieve sealing and connection. This layer generally requires a thickness between 0.02-0.05mm, with high adhesion and anti-aging properties; In production, specialized film switch double-sided tape is generally used. Some film switches require waterproof and high-temperature resistance, so it is necessary to use different materials for the adhesive layer according to the needs.

3. Control circuit upper and lower layers

This layer is made of high-performance polyester film (PET) as the carrier of the switch circuit pattern, and silver paste, carbon paste or gold paste is screen printed on it with special technology to make it conductive. Its thickness is generally within 0.05-0.175mm, and the commonly used method is 0.125MMPET

4. Adhesive layer

It is located between the upper and lower circuit layers and plays a role in sealing and connecting. Generally, PET double-sided tape is used, with a thickness ranging from 0.05-0.2mm; When selecting this layer of raw materials, full consideration should be given to the overall thickness, insulation, circuit key package feel, and sealing of the product.

5. Reverse adhesive layer

The use of backing tape is closely related to the material used to stick the film switch, and commonly used materials include double-sided tape, 3M tape, waterproof tape, etc.

The raw materials for membrane switches and panels should not only have flatness and printing adaptability, but also have the characteristics of flexibility and high elasticity.