1. Panel layer
The panel layer is generally made of exquisite patterns and text printed on colorless transparent sheet materials such as PET, PC, etc. Less than 0.25MM. Because the main function of the panel layer is to play the role of identification and keys, the selected material must have high transparency , High ink adhesion, high elasticity, high toughness and other characteristics.
2. Surface adhesive layer
The main function of the surface glue is to closely connect the panel layer and the circuit layer to achieve the effect of sealing and connection. The thickness of this layer is generally required to be between 0.05 and 0.15 mm, with high viscosity and anti-aging properties; in production In general, special membrane switch double-sided adhesive is used, and some membrane switches require waterproof and high temperature resistance. Therefore, the surface adhesive must also use materials of different properties according to needs.
3. The upper and lower layers of the control circuit
This layer uses polyester film (PET) with good performance as the carrier of the switch circuit pattern, and uses a special process to silk-screen conductive silver paste and conductive carbon paste to make it conductive, and its thickness is generally 0.05-- Within 0.175MM, 0.125MM PET is the most common.
4. Laminated layer
It is located between the upper circuit and the lower circuit layer and functions as a seal and connection. Generally, PET double-sided tape is used, and its thickness ranges from 0.05 to 0.2MM; when choosing this layer of material, the overall product should be fully considered Thickness, insulation, feel and airtightness of the circuit key pack.
5. Adhesive layer on the back
The use of adhesive is closely related to the material of the membrane switch. Common double-sided adhesives, 3M adhesives, waterproof adhesives, etc. Are commonly used.
