Film switch is now the majority of intelligent electronic products, home appliances, office equipment, electromechanical and electronic toys and other products, the membrane switch for electronic products is a very important position, so the quality of the membrane switch directly affect the quality of the product, Shenzhen Xin Jie Jia Electronic Film Switch Co., Ltd. has been committed to providing customers with the best quality membrane switch in the film switch production screen selection is very important, how to choose the screen?
We know that the conductive silver paste by the conductive properties of metal silver particles and conductive resin and solvent mixture, and metal silver particles is to determine the resistance of the main road resistance factors. As the different manufacturers of silver paste its metal silver particles size, composition and shape of different, so in the printed circuit, the silver should be managed to allow the particles through the wire mesh, which requires the switch line printing when the selected wire The network should not be too high too dense wire mesh, mesh high, relatively small gap, printing will hinder the silver through. This printed out of the circuit, the resistance value is larger, the membrane switch can not reach the customer required a small resistance. Although the fine screen can print straight lines, so that printed lines beautiful graphics, but in microscopic state, it is only a layer of loose structure, metal silver particles of solid content is very small, it is because they Most of the failure to pass through the screen, such a graphic / fi only resistance value is large, while the line current smooth bad, will also affect the line life, it can not meet the practical application. According to experience, the general selection of 200 mesh ~ 250 mesh screen is appropriate In addition, the same mesh size of the screen due to the thickness of the production of different materials, the size of the gap is not the same. For the switch line, should use monofilament, plain weave thin wire mesh. This wire mesh is fine, the gap is small, the surface is smooth, the silver paste will not be embedded in the screen, which is conducive to the printing of silver paste, printed out of the line healing, silver particles of good continuity, full of full, Low resistance, long service life. In short, in order to allow conductive printed materials, especially silver paste in the silver tablets through the smooth, you need to choose a slightly lower mesh enough net, and require a smaller diameter, hole width is relatively large. The smoothness of the circuit pattern refers to the sharpness of the edge, it is not only for the appearance of consideration, more importantly, take into account the impact of electrical parameters. It is possible to reduce the edge impedance of the adjacent wires, especially in the case of high temperature and high humidity, which easily lead to the migration of silver ions along the edge of the wire and cause the silver ions to migrate, resulting in fault such as short circuit between lines.