Screen printing principle and process overview
Screen printing belongs to screen printing, which, together with letterpress, lithography and gravure printing, is called “four major printing”.The principle of screen printing is;During printing, the dye is transferred to the substrate (such as textiles, paper, ceramics, etc.) through the holes of the screen frame through certain extrusion, to form graphic characters, as shown in Figure 1-1.In the area with holes in the mesh frame, the dye can penetrate to the substrate to form a pattern. In the area where the mesh hole of the mesh frame is blocked, the dye cannot penetrate, so the pattern cannot be formed on the substrate.
Sensitive glue plate method is widely used for modern is a kind of method, plate making, silk screen as the carrier, will screen tension in net box, and then at sensitive glue coated, formed the initial plate membrane, and then the initial blank plate membrane and a pattern fit closely together, through the exposure and development process of 27, does not need to be part of the dye by light irradiation on a plate and curing on the screen, form version of the film, the hole be sealed block at this moment, when printing dye cannot through the net frame.The screen frame needs to pass through the dye plate film, after development washing is removed, the hole is not closed blocked, printing dye can pass through the screen frame, on the substrate to form a pattern.
When printing, the dye is poured into the mesh frame. Under the condition of no pressure, the dye will not automatically pass through the mesh substrate. When the scraper is at a certain Angle and the pressure contact frame is scraped, the dye will pass through the mesh frame to complete the printing of the pattern.
For the main process of screen printing, the first choice of screen, according to the requirements of textile printing patterns and the size of the size of the screen to select the corresponding type and size;Then choose the screen frame, then stretch the network, will fit the screen frame and screen coated with glue for bonding;At present, the general use is photosensitive platemaking method for platemaking;Then print, development;After the printing screen frame is finished, it is installed into the fixing frame on the printing arm for printing and production begins.