Flexographic Printing Laser Engraving Ceramic Anilox Roller and Ink Transfer System (I)

Modern flexographic printing is the ability to accurately control the amount of ink transferred to the plate through the anilox roller to obtain the desired print patterns or lines, so that the anilox roller is also referred to as the transfer metering roller. This article will focus on the selection, application and maintenance of laser-engraved ceramic anilox rollers and their ink transfer systems.
First, the comparison of laser engraving ceramic anilox roller and metal anilox roller The anilox roller is mainly divided into metal anilox roller and laser engraved ceramic anilox roller. The metal anilox roll is usually carved on the surface of the metal roll by electric carving or mechanical extrusion, and then processed by a chrome plating process to form a hard metal chrome-plated layer; the laser-engraved ceramic anilox roll is on the surface of the treated base roll The alloy is sprayed as a primer layer, and then the ceramic layer is plasma sprayed at a high temperature. After diamond grinding and polishing, under the control of a computer, a sharp and sharp cell site is accurately carved with a high-energy laser beam, and then fine polishing is performed. .
The engraving process adopted by the metal chrome anilox roller determines that the top of the mesh formed by it is wider than the bottom. As long as the top is slightly worn, the width and cellar opening of the mesh cavity must be reduced, and the general wear (the depth of the cell depth decreases). %, the amount of ink transferred (or coating) will be reduced by about 30%. In actual testing, we can observe the width of the network wall through a high magnification network microscope to confirm the degree of abrasion of the anilox roller. As the width of the net wall becomes larger, the opening of the net hole becomes smaller, and the volume of the net space must be correspondingly smaller, that is, the amount of ink transferred is reduced accordingly.
Laser engraved ceramic anilox roller is different from metal anilox roller in cross-section shape of the mesh, especially for the new generation of high-energy laser engraved cells, where the correlation between the top and the bottom is not significant, and the same number of anilox rollers The laser-engraved network hole has a larger opening than the metal roller, and the amount of ink transferred is also correspondingly increased. This is of great significance for printing full-version, colorful, and large ink-absorbing prints.
Metal chrome-plated anilox roller cannot be engraved with high wind number anilox roller because of the limitation of materials and manufacturing process. Obviously it cannot meet the requirement of high-line number flexo printing; while laser engraved ceramic anilox roller is different, the number of engraving lines can be Above 1000 lpi (line/inch).
In addition, the service life of the ceramic material is much higher than the hardness of the metal chromium. Therefore, the service life of the laser-engraved ceramic anilox roller far exceeds that of the metal anilox roller, especially in systems using a steel scraper to transmit ink. Big.
Second, the characteristics of high-quality ceramic anilox roller An important feature of modern flexographic printing is the use of high-quality laser engraving ceramic anilox roller.
Laser Engraving Ceramic Anilox Rollers The quality and performance of the anilox rolls produced by the manufacturer are different due to the different spray materials used by the manufacturer, the processing technology used, the engraving equipment used, and the detection methods used. As far as laser engraving equipment is concerned, the ultra-high-power laser beam can accurately sculpt cells with sharp outlines, steep walls and very smooth walls, and the top and bottom areas are similar, increasing the amount of ink carried. The laser-engraved ceramic anilox roller with the same number of screens can increase the ink loading by 15-25% compared with the metal anilox roller. Because the wall of the cell wall is smooth, the amount of retained ink at the bottom of the cell cavity is reduced in the process of ink transfer, and the effect of rapid ink transfer can also be achieved, and also the cleaning of the cell site is facilitated, especially the anilox roller with a high number of screen lines.
With YAG laser engraving technology, the grease not only has a smooth hole wall, but also has a neat network wall, a high degree of smoothness, accurate ink transfer, and low blade wear, which can extend the service life of the printing plate. Therefore, YAG laser engraving ceramic anilox roller has a long service life.
At present, the world's most advanced high-power, high-precision YAG laser engraving machine can dedicate 1600 lpi anilox roll, and the general CO2 laser engraving anilox roller can reach 1000 lpi at most.
In the manufacturing process of the laser-engraved ceramic anilox roller, the dense combination of the base roller and the ceramic layer is supported by a “intermediate layer”. The interposer is made of stainless steel alloy. It has both acid resistance and alkali resistance, increases the strength of the anilox roller, and can firmly integrate the base roller and the ceramic layer, and effectively prevents the ink from forming. The corrosive penetrates the base roll. The use of special super tough ceramic bonding layer materials and super hard ceramic layers can increase the service life of the anilox roller and reduce the user's cost. The recently introduced type of laser-engraved ceramic anilox roller for narrow-width unit-type soft machine is more suitable for quick change plate system. One person only needs to gently... (to be continued)