Membrane switch quality inspection problem
Membrane switch quality testing is a very important task. Establishing a comprehensive quality assurance system is a top priority for a successful membrane switch company. In the membrane switch quality inspection work. Apart from paying attention to the color rendering properties of inks that are familiar to screen printing workers and the color reproducibility of customers, it is more important to pay attention to the intrinsic qualities of membrane switches, such as key operation force, life span, peel strength, and high temperature and low temperature. , Constant temperature damp heat and loop Yin, insulation Yin, pressure and other testing indicators.
1. Membrane switch detection requirements
Appearance quality inclusions, stain inclusions, less than 2 / dm2. Inclusions, the length of the stain is not more than 1 mm. Do not accumulate, at least 50MM away from the scratches; scratches less than 1 / dm2, the length of the scratch is not more than 20MM, the depth and width are not greater than 50um; depth is not greater than 1um scratches are allowed.
The color of the same batch of products should be no significant difference, the color printing layer should have enough hiding power, and the color and structure under the observation of the reflected light cannot be clearly seen; when printing the transparent ink layer, the overlapping portion of the two colors must not exceed 1 mm. The color deviation caused is allowed; the edges of printed characters and color blocks are not clear or larger than 0.15mm.
Membrane switch size should be consistent with the provisions of Table 1, the membrane switch parallelism and perpendicularity of the two adjacent sides should meet the requirements, the lead wire with the center of the distance between adjacent conductors is generally 2.54mm.
4. Peel strength
The peel strength of each adhesive layer of the membrane switch shall not be less than 8N/25mm.