The difference between screen printing and its embossing, gravure, and lithography
The four printing methods of letterpress printing, gravure printing, lithographic printing and screen printing are different, and each has its own advantages and disadvantages. However, among these four modern mainstream printing methods, screen printing is obviously the most widely applicable printing technique. The substrates it can print include paper, plate making, and wood. Plastics, textiles, ceramics, metals, furs and more. It can not only print flat objects, but also print on various special irregular shapes. This characteristic is screen printing.
Compared with the most obvious advantages of the other three printing methods, of course, the technical advantages of screen printing are not only these.
1.The principle of screen printing
Screen printing is one of the most common methods in stencil printing. The screen is taut on the screen frame, and a mesh template is made on the screen to block the non-graphic part, and the mesh of the graphic part can pass through. The ink is pressed by a squeegee, and is leaked from the mesh of the graphic part to the substrate. The traditional plate-making method is hand-made. The screen frame is coated with photosensitive adhesive, which can be applied as many times as needed.
A photosensitive film is formed, and finally the graphic base plate is pasted on the dried UV film for printing. After exposure, development, and washing of the printing plate, the photosensitive glue that has not been solidified by UV irradiation is washed clean, because the screen plate needs to be printed. The mesh of the graphic part is not closed, and the printing pressure is applied to the ink to appear on the substrate through the mesh.
2.Screen making tools
The tools and materials used in screen printing are: wire mesh above 200 mesh, screen frame, scraper, mesh stretcher, mesh sealant, mesh cleaning liquid, film, paint, etc. The most widely used plate-making method in modern screen printing is the photosensitive plate-making method.
3. Screen printing process
(1) Use transparent film for color separation and plate making of the designed design.
(2) Scrape the prepared photosensitive adhesive on the screen with a scraper in the darkroom, dry it in the oven, and repeat it several times according to the printing requirements.
(3) Publishing. Paste the film on the screen plate for UV exposure. The photosensitive adhesive that is not blocked by the film is irradiated with UV light and solidifies to block the mesh. After exposure, the excess photosensitive film is washed off with water and dried. Close the net.
(4) The screen plate after drying is fixed on the hand I or the mechanical printing pad, and printing can be carried out on the good version.