[China Packaging Network News] Along with the development of the packaging and printing market, the packaging technology has also matured and diversified. In order to pursue the level of packaging of goods and increase the added value of the goods, a new technology that uses the imitation gold effect on the packaging of goods has been born.
I. What is sweeping technology?
I. What is sweeping technology?
Sweeping gold is a special post-printing process in fine prints. It attaches special metal powders to specific parts of commodity packaging or label prints to achieve gold glitter effect. This kind of technology can get realistic metal texture and better luster. At the same time, the pattern is fine and overprinting is accurate. After sweeping gold, the product's metallic sand grains and light diffuse reflection effect are better, and the metal texture is more real, giving people a visually distinct three-dimensional effect, which is different from gold printing and bronzing.
Second, sweep gold craft
The process of sweeping gold is actually very simple. Put the sheets of gold sweeps on a monochrome or two-color offset press. Use a special PS board to print a layer of viscous glue on the parts where you need to sweep the gold, and then press the paper into the sweeper. Machine, sweeping the powder and polishing, gilt, etc. can be completed.
The gold sweeping process is completed by a sweeper. The sweeper is mainly composed of a paper feeding mechanism, a coating mechanism, a polishing mechanism, a cleaning mechanism, and a delivery mechanism. The process flow is as follows: The gold sweeper generally needs a single-sheet (double-color) offset press (to remove the delivery device) to connect with the sweeper. Using the color separation film of the printed product to produce a PS plate dedicated to the gold sweeper, installed on the offset printing machine, the registration work can be completed by adjusting the rules of the offset printing machine. Use the PS plate to print a thin, uniform primer (commonly known as "sweeping gold") on the site where the gold powder is to be printed.
The underprinted printed matter is sent to a rubber conveyor belt with a suction passage on a gold sweeper paper conveyor device, and a coating device consisting of a gold powder filling device, an applicator with an ink fountain roller, and a coating roller. start up. The applicator roll rotates. When the side of the applicator roll where the gold powder is adsorbed is transferred to the top of the paper, this part is switched from inhalation to air blowing, and the gold powder is uniformly sprayed on the surface of the paper. The four special polishers rubbed and polished with the gold powder on the paper, and the gold powder printed on the paper with the primer was stuck on the paper.
The gold sweeper uses four special sheet metal belts to perform reverse reciprocating movements between each other to improve the metallic luster and adhesive fastness. The latter two have strong suction ducts, plus the high vacuum suction of the cleaning mechanism. Multi-channel cleaning cycle system, so you can quickly and cleanly clear the excess gold powder on the sheet, these extra gold powder can be recycled, will not cause environmental pollution, it will not be wasted. In the end, the paper collection organization completes the paper collection and finishing work.
If the printing manufacturer owns a multi-color printing press and UV drying device, on-line gold scanning can be performed. That is, the printing sheet is printed in the first few color groups of the multi-color printing machine and fully dried by the UV device, and then at the end A color set is coated with a sticky ink, and then connected to a gold sweeper to perform gold scan. In the above situations, when no sweep is needed, the gold sweeping equipment can be separated from the printing press within a few minutes, so that the printing press can be printed normally.
Third, the characteristics of sweep gold craft
Sweeping gold has unique advantages when compared with other imitation gold effect processing techniques in other fine prints. Gold printing and gilding, as a widely used process, have many advantages, but there are also some deficiencies. For example, at present, gold can be offset, gravure, flexo, and screen printing, especially offset printing and gravure printing. These two printing speeds are relatively fast. The offset ink layer is thin, and the metallic luster is not very good. The gravure ink layer is thicker and the gloss is better than that of offset printing. However, the metal texture is not strong enough during large-area printing, and the deformation is relatively serious when printing small characters and thin lines. A traditional process, the metal is also very strong, but high energy consumption, relatively low efficiency, registration is difficult, very small graphics and a large area of ​​bronzing, the quality is not easy to control.
Although the matte printing has a good metal texture and luster, the production efficiency is low, and the discarded packaging is not easy to recycle, which is not conducive to environmental protection. The gold-sweeping technology has a simple operation process, high production speed (up to 7500 sheets/hour) and low cost. Regardless of the thickness of the text and the size of the area, good results can be obtained. Gold powder color is also varied, such as gold, silver, red gold, copper, green, graphite, tan, lemon yellow, peacock blue, etc., can be described for everything, and different granularity, can show a rich color .