Steel drum screen printing and plate making (1)

Yang Wenliang

Steel drum screen printing is a new technology developed in recent years. It not only has good printing quality, but also is beautiful, generous and efficient. It is an ideal process for printing the outer surface of steel drums. At present, it is mostly used for the printing of characters and patterns on the surface of steel drums. The original engraving printing process has been gradually eliminated due to its small capacity, poor quality, low efficiency and high pollution.

First, the principle of steel drum screen printing

The basic principle of screen printing of steel drums is that part of the mesh of the screen printing plate can pass through the ink and leak onto the surface of the steel drum; the mesh of the rest of the printing plate is blocked, and the ink cannot pass through the steel drum. A blank is formed on the surface.

The more commonly used plate making method is photochemical plate making. The plate making method uses a wire mesh as a support body, and the wire mesh is stretched on the net frame, and then the photosensitive adhesive is coated on the net to form a photosensitive plate film, and then the sun bottom plate is adhered to the plate to be plated, exposed, Development, the portion of the printing plate that does not need to be inked is exposed to light to form a cured plate film, and the mesh is sealed, and the ink is not transparent when printing; the mesh of the portion of the printing plate that needs to pass the ink is not sealed, and the ink is transmitted during printing. Ink is formed on the surface of the steel drum.

When printing, the ink is poured into one end of the screen plate, and the ink does not leak through the mesh hole on the surface of the steel drum without external force. When the ink is scraped with a squeegee at a certain angle of inclination and pressure, the ink is transferred to the steel drum under the screen through the screen, thereby realizing the reproduction of the pattern. The stencil printing and letterpress printing, gravure printing, lithography and the modern four major printing. Screen printing is one of the main printing methods in stencil printing.

Second, steel drum screen printing process summary

The initial process of screen printing on steel drums is a full draft. At this time, it is necessary to clarify the size, shape, position, number of prints, etc. of the steel drum. According to these requirements, the accuracy of the printed pattern, the accuracy of the pattern, and the quality of the image are determined. For steel drums, since they are mostly used outdoors, special attention should be paid to their weather resistance when selecting inks. The screen printing process is shown in Figure 1.

Screen printing is based on the original, then the plate making method, the printing process, and determining which printing material should be used. Taking the wire mesh as an example, its material now uses nylon mesh for ideal elasticity and recovery, as well as the ability to print on the uneven surface. Stainless steel wire mesh is often used in printing requiring high precision. The method of plate making generally has two methods of manual cutting and plate making and photosensitive plate making. The former is suitable for patterns that are not very accurate and can be drawn; for printing patterns that require high precision and emphasize the tone level, photosensitive plate making must be used. In the photosensitive plate making method, a direct method can be used for producing a printing plate having strong printing durability. This method is inferior in image quality because the positive base plate is closely attached to the photosensitive film of the screen during printing. When high quality images are required, it is best to use indirect plate making.