Screen printing mesh should pay attention to the following problems
In the batch screen printing mesh, the emulsion is applied, and the prepared photosensitive liquid is placed in a stainless steel tank, and the photosensitive liquid accounts for about half of the groove. The coating tank is in contact with the lower end of the inclined screen, and while the groove is inclined to flow out of the photosensitive liquid, the groove is slowly and uniformly lifted up and applied along the screen surface. The coating speed should not be too fast, too fast will cause the emulsion to foam, and the film surface will produce pinholes; too slow will cause uneven coating of the emulsion. In order to obtain the best coating effect, it is best to apply the coating from the side that is in contact with the substrate at the time of printing. The coating area should be slightly smaller than the screen frame, and then the screen is turned upside down and coated once again. The reverse side of the screen is coated and dried to fill the mesh with the emulsion. It is best to dry with hot air at 30 to 35 ° C, which can shorten the drying time. If the temperature is higher, the screen will produce hot fog when it exceeds 40 °C. The sensitivity of the emulsion in the liquid phase is low, the sensitivity rises with the drying of the coating film, and the specified sensitivity is achieved after it is completely dried. Therefore, it is sufficiently dried before the printing, and the printing is completed in a short time after drying. . Of course, due to the different production conditions of various manufacturers, the coating method and the number of times are also different. Since the dust on the plate surface causes pinholes in the screen, keep the room clean. At the same time, the screen must be handled poorly, which will cause too much pinching on the surface of the screen. When the emulsion is coated, the dry place is too bright, which will cause the fog of the full-page image of the screen to affect the sharpness and saturation of the printed matter. 2. Batch Screen Printing In most manufacturers, screen printing is not done by one person alone, but by many people working together. Only the previous process is responsible for the next process, and the self-inspection and self-inspection of the respective processes are carried out, and the quality is strictly controlled to produce the screen prints that the user is satisfied with. The perfect match between screen, ink and printing is a prerequisite for good prints. The quality of the printing plate directly determines the quality of the printed product. Printing is only a test of the quality of the plate making. However, under the premise of stable printing quality, the printing workers are not taken lightly, and the ideal printed matter can not be obtained. More waste, defective or defective products. Before batch printing, the printing screen should be fixed, pour into the ink test, check the layout of the layout and text, ink color, ink layer thickness, specifications, registration accuracy and so on. If the registration accuracy is poor, you can adjust it according to the fine adjustment knob on the front of the frame; if the hue of the ink is wrong, check if the wrong ink is used and replace it immediately; if the ink is bad, use the solvent to wipe the part of the printing plate to make the ink transparent. The performance and the wettability of the substrate are improved; if the tone and level of the graphic are greatly different, the printing screen should be replaced immediately.
PREVIOUS： What is the main difference between screen printing mesh and other printing methods?
