Talk about ink capillary transfer printing

The ink is transferred from the ink holes to the surface of the printing material through the pores. The drum rolls to the end of its circumference to get the largest sheet. After the rotation is completed, the large drum leaves the surface of the plate cylinder, and the plate cylinder can be cleaned and disassembled. The color proofing after the second color is repeated after the previous color is dried and the same process as described above is repeated.

Flexible packaging materials will cause the printing material to expand and contract during printing. When the printing company is making a version of the drum, there is a requirement for increments between the colored building drums, which will bring certain difficulties in proofing. Experienced operators can pass through the gaps of the outlets. Make proofs with high registration accuracy.

The Japanese machine's ink transfer is to transfer the ink to the substrate by pressing the impression roller through the gravure plate cylinder. The machine speed is generally about 30m/min, but the impression cylinder is separated from the gravure cylinder from the start to the end. The speed is not the same, because the substrate is tightly wrapped in the surface of the drum, under the inertia of the drum, resulting in faster speed, the second lap speed will be faster than the first lap. The British machine completes the transfer of ink by pressure on the impression cylinder to drive the plate cylinder. The speed of the impression cylinder itself is kept constant. The speed of the substrate that is wrapped in the impression cylinder is the same from beginning to end. This solves the problem of the inconsistency in the rotation speed of Japanese machines. In the proofing process, the substrate is firstly wrapped on the impression cylinder, and then the proof is printed in the printing sequence according to the characteristics of the printing and the surface printing of the platen cylinder.

The printing plate in the plate is generally transparent, and the color is first played in the proofing process, and then light colors are created on the basis of the previous color. For example, only the four-color electric image and the white plate are printed. Usually, the black version is used first. , and then hit the educational version, the magenta version, then the yellow version, and finally play the white version on the basis of these four colors. The printing sequence of the table printing plate is the opposite of the printing plate in the plate. Most of the substrates for the printing plate are opaque, and proofing is performed from the light-colored version to the dark-colored version. When proofing, you must also pay attention to the important factor of proofing ink.

The gravure proofer does not have an ink tank. When the impression roller is in close contact with the gravure plate roller, the ink to be dispensed is manually poured onto the gravure plate cylinder. Because the speed of the proofer is not high, it is determined that the viscosity of the ink used for proofing should not be too low, otherwise it will cause a paste plate. High-speed gravure printing machine can be opened to 160m/min under normal circumstances, the ink viscosity is about 16s, but the ink viscosity used in gravure printing should be adjusted to about 20s. The slow speed of proofing, the large viscosity of the ink and the low hardness of the rubber on the impression cylinder are all conducive to the full transfer of the ink to the substrate, and the color of the proof is relatively bright.

If the proofing does not add ink to dilute the ink, it will make the printing company suffer too much, because the printing company is difficult to print a very bright and bright color effect. It is necessary for the platemaking company to dilute the ink when proofing, so that the printing company will be much easier to do color proofing according to the gravure proofs. In the entire gravure platemaking process in which electric sculpture has achieved no film engraving, the department with the most human influence factors is the gravure proofing workshop. The dilute of the proofing ink, the difference in dilution, the different pressure between the gravure plate cylinder and the impression cylinder, the angle of the blade, the installation method and the different pressure, the distance between the blade and the embossing point will be different. This kind of effect has an effect. In the proofing process, the relevant parameters should be adjusted according to the different substrates, surface printing and in-print characteristics, so that the perfect gravure proofs can be produced and the professional production level of the plate-making company can be played.