1. According to the characteristics of gold ink, paper properties, design gold layout structure
The design of the layout structure of letterpress gold products must pay attention to the nature of the paper used in order to achieve better printing results. Such as coated paper, glass powder card and other smoothness of the paper can be used in a large area of ​​the gold version, but also take into account the characteristics of bright white paper, in the background gold version should pay attention to highlight the white deco decoration, that is, the use of paper The appropriate gloss of the surface gloss and the golden layout, and strive to make the layout to achieve a "brilliant" aesthetic effect. Papers with poor paper smoothness, such as offset paper, should be printed with as little gold as possible. In addition, in the same layout, the graphic size, thickness should not be too different. Yin, Yin, Yang characters should not be too small, so as not to paste version. The golden layout should be superimposed on the dark field as much as possible. Such as red, blue on the gold effect is better. And printed on origami or yellow bottom, the effect is not obvious.
2. It is necessary to turn off the process technology of the good plate to ensure the quality of the gold
The printing pressure is even and full, which is the process requirement for preventing the printing from blooming and ensuring the printing quality. The traditional wood-bottom-mounted version is not suitable because it lacks solid and flatness and produces poor printing results. Therefore, the gold printing plate should be made of metal materials with high compressive strength and good flatness, such as magnetic plate holders, aluminum trays, etc., which can better prevent the variation in the pressure during the printing process, resulting in the phenomenon of ink blooming. When the layout is not smooth enough, it can be used in the roller lining with a scrap paper paste pad, paste the location to be accurate, the glue to a thin brush and uniform, to ensure that the printing plate surface pressure is sufficient and uniform, and maintain a good ink quality.
3. Reasonably adjust the rubber roller to improve the gold printing process effect
The difference between letterpress printing and printing of other color solid maps is that it requires less uniform ink roller and ink roller, the better, because the faster the printing machine speed, the greater the heat generated by the rotating friction between the ink roller, It will cause the gold powder particles in the gold ink to condense and dry on the ink roller, and the accumulation of the remaining ink will be more and more, which will inevitably cause the decline of the gold ink transfer performance. In addition, due to too many ink rollers, gold powder can not be quickly transferred to the printing plate. With the increase of the friction system of the ink roller, the protective layer (ie, stearic acid and other substances) on the surface of the gold powder is easily destroyed, resulting in oxidation and discoloration of the gold powder. Loss of shine.
The printed gold ink must be made of a rubber roller that is both flexible and flexible. The surface of the rubber roller must be smooth, smooth, and free of scratch marks. The hardened, cracked and wrinkled skin layers of the rubber roller cannot be used. When printing, the pressure between the rubber roller and the iron roller should also be properly adjusted. Both sides of the adjacent ink roller should maintain good contact. The contact roller brush between the ink roller and the plate should also be kept light and even to avoid the occurrence of stencil.
In summary, the topographic printing process through the above control, not only can improve production efficiency, but also can effectively guarantee the printing quality.