2. Laser plate making technology
(1) Data transmission reduces data loss.
(2) The digitized process reduces the empirical operation.
(3) Achieve direct plate-making without negative film.
(4) Eliminates dust problems.
(5) No vacuum is required.
(6) The dot gain due to the diffuse reflection of UV light is eliminated.
(7) The edges of the outlets are more vertical and sharp. The highlights and lines are precise and delicate. The benefits of flexo plate making are:
(1) The highlight part is brighter and the gradation is smoother. (2) The tone reproduction is wider.
(3) The dot gain of the printing plate is reduced.
(4) The level of shadowing is preserved.
(5) Fine text and clearer lines.
The comparison between laser plate making samples and traditional plate making samples is shown in Figure 1.
Most users require the plate-making company to produce high-line printing plates. In fact, they are subjected to offset printing or gravure printing. The number of screen lines needs to be determined according to the anilox roller configured by their company. According to the author's experience, a difference of less than 20 lines/inch usually does not have much visual difference. However, the plate printing force has a greater difference. For example, the resistance of a 1 75 line/inch plate will be strong. It is 40% less than the 150 line/inch plate Narayin, which is also higher from the printing cost.
Reasonable process arrangement
Reasonable processes also have a great impact on printing. As more flexographic printing products are now transferred from the original offset or gravure, the process also needs to be changed, as shown in Figure 2. The printed sample is originally a gravure sample. If the flexographic printing is printed in monochrome, the ink layer in the field is not as gravure. Therefore, we need to do two printings in the field so that the solid can be printed with the concave. Print samples are close, dot gradients can also get delicate results.
Design for different printing methods, such as flexographic printing design, can design multi-color spot color, because the flexographic printing is transmitted by the anilox roller. Compared with offset printing and gravure printing, the ink color is more Stable, because the anilox roller transfer ink is quantitative, as long as the same anilox roller, at different times it is transferred to the printing plate of the ink is basically the same, so the ink is stable.
Usually offset printing only YMCK four colors, many small text is overprinted with two or three colors. Since the flexographic printing has lower registration accuracy than offset printing, if the flexographic printing also uses multi-colors to superimpose small text, its effect is definitely not good, so spot colors can be used for printing at this time. This will not only reduce the problem of overprinting, but the hue of the text will be stable.
(to be continued)
