What should be paid attention to in screen printing?
Silk screen printing is the abbreviation of "screen printing". Screen printing is to stretch silk fabric, synthetic fabric or wire mesh on a frame, and make a screen printing plate by hand-engraving film or photochemical plate making. The modern screen printing technology uses a photosensitive material to make a screen printing plate by photolithography (so that the screen hole of the graphic portion on the screen printing plate is a through hole, and the non-graphic portion of the wire mesh hole is blocked. live). During printing, the ink is transferred to the substrate through the mesh of the graphic portion by the extrusion of the squeegee to form the same graphic as the original. The printing mesh equipment is simple, easy to operate, simple in printing and plate making, low in cost, and strong in adaptability.
Here are some questions to pay attention to in screen printing.
1. Cleaning of Printing Sites With the continuous improvement of printing precision requirements, especially for high-precision printing of printed circuit boards and electrical components, high demands are placed on the environment. Generally, the printing workshop and the plate making workshop must be cleaned, and there is no dust in the air, otherwise the printing quality will be affected. For workshops with high printing accuracy requirements, air purification equipment should be installed when necessary to keep the printing and plate making workshop clean.
2. Temperature and humidity The temperature and humidity of the spring, summer, autumn and winter seasons vary greatly, and the printing accuracy is also relatively large. Especially the multi-color overprinting has more obvious influence. Therefore, the indoor humidity and temperature are required to be relatively stable. And adjust the indoor temperature and humidity according to seasonal changes to ensure the printing dimensional accuracy.
3. Fully understand the nature of the substrate Because screen printing has a wide range of applications, there are many kinds of printing materials, and the shape of the substrate is different. Before printing, select the appropriate ink and solvent and scraper according to different requirements.
4. Pay attention to the problem of drying net: According to the product itself and the printing requirements, choose the appropriate screen, that is, the mesh should be suitable; the film surface is generally based on the screen version; the exposure time is based on the actual situation of the outlet, and the exposure is determined according to the exposure experience. Time; after exposure, the plate should be thoroughly cleaned; the drying should be thorough; remember the double exposure.