In recent years, China's printing industry is striving to transform into a sustainable development industry, and green printing has thus become the main direction of China's printing industry. Especially in the cigarette packet printing industry, as China's tobacco industry continues to have strict requirements on the limits of various harmful substances in cigarettes and their packaging, cigarette packet printing companies have sought green and environmentally friendly printing materials. The gravure water-based ink uses water as the main solvent, and no VOCs are emitted during the printing process, which can improve the safety of the operating environment, protect the health of the operator, reduce the organic solvent residue of the printed matter, and reduce the energy consumption. Therefore, it has become the future development of the printing industry Inevitable direction. In recent years, China's printing industry is striving to transform into a sustainable development industry, and green printing has thus become the main direction of China's printing industry. Especially in the cigarette packet printing industry, as China's tobacco industry continues to have strict requirements on the limits of various harmful substances in cigarettes and their packaging, cigarette packet printing companies have sought green and environmentally friendly printing materials. The gravure water-based ink uses water as the main solvent, and no VOCs are emitted during the printing process, which can improve the safety of the operating environment, protect the health of the operator, reduce the organic solvent residue of the printed matter, and reduce the energy consumption. Therefore, it has become the future development of the printing industry Inevitable direction. However, the use of water as the main solvent in gravure water-based inks also brings some problems to its application, such as low printing durability of printing plates and uneven transfer of solid plates. Below, based on my own years of practical exploration, the author summarizes the main causes and solutions of these problems and the precautions for storage and use of gravure water-based inks, hoping to inspire and help colleagues in the industry. 1. Shadow (fog version) phenomenon The main reason: the friction coefficient of gravure water-based ink is higher than that of solvent-based ink, the blade is easy to wear, or the surface tension of water is large, and the affinity with metal is high, resulting in the blank part of the printed pattern due to the ink scraping at the corresponding position of the printing plate. It is clean and accompanied by a faint color, that is, the shadow (fog version) phenomenon. Solution: ①Use a scraper blade with good abrasion resistance during printing, and increase the pressure of the scraper blade appropriately during the printing process; ②Add an air blowing device between the scraper blade and the platen roller; ③Grind the printing plate; ④Use ethanol to reduce concave The viscosity of water-based printing ink. 2. Low printing durability The main reasons: ①improper use of scraper and pressure; ② the hardness of the chromium layer of the printing plate is not enough; ③ there are many printing quality problems that cause excessive polishing of the printing plate; ④ water causes certain corrosion of the printing plate (metal). Solution: ①Standardize the operation methods of the operators, improve their operation technical level, and reduce the occurrence of printing quality problems; ② It is recommended that the plate-making factory increase the hardness of the chrome layer of the printing plate; ③ The replaced printing plate should be cleaned and kept in a ventilated environment . 3. The field version is not smooth The main reasons: ①The water-based gravure ink uses water as the main solvent, and the surface tension of water is large, which makes it difficult for the gravure-based water-based ink to wet and level on the surface of the substrate; ②The surface of the gravure-based water-based ink dries quickly after entering the oven Conjunctiva, the water in the membrane is temporarily closed, but when it continues to be heated, it will form water vapor to escape. When this energy is large enough, it can break through the ink film, thereby forming small white spots similar to craters on the surface of the ink film. ; ③The pH value of the gravure water-based ink changes during the printing process, resulting in uneven transfer. Solution: ①Ink suppliers are needed to reduce the surface tension of the gravure water-based ink, so that the gravure water-based ink can be fully wetted and leveled on the surface of the substrate, and the transfer is more smooth; ②The gravure water-based should be appropriately increased during the printing process Ink viscosity, meanwhile reduce oven temperature, increase air volume, reduce printing speed, and ensure that gravure water-based ink dries thoroughly; ③Ink must be filtered every time ink is added, and the viscosity of ink must be strictly controlled; ④The printing process should use a small number of times Add new ink to ensure the stability of the pH value of the gravure water-based ink. 4. Pasted (blocked) version, the color of the layout is inconsistent The main reasons: ①Other ink impurities are mixed on the ink tank, ink tank, and blade holder; ② Solvent-based ink or other solvents are added to the gravure water-based ink; ③ The angle of the blade is not adjusted properly; ④ The blade is not raised after the stop. The printing plate is idling; ⑤ The pH value of the ink is too small, resulting in an increase in viscosity; ⑥ The printing plate is severely abraded and the net holes become shallow; ⑦ There are few parts of the printing plate immersed in the ink. Solution: ①Before printing with gravure water-based ink, the ink tank, ink tank, and blade holder must be thoroughly cleaned; ② The ink must be filtered when adding ink; ③ The angle of the blade must be carefully adjusted, the angle must be appropriate, and the pressure cannot be too large; ④ After stopping, the scraper needs to be lifted to allow the printing plate to dry; ⑤The printing plate must be cleaned before starting up. If the paste is serious, the printing plate must be taken out. After immersed in ethyl acetate or washing powder, rub it clean; ⑥It should be used during the printing process Add new ink in a small amount of times, and when adding ink, the viscosity of the new ink must be adjusted to the printing viscosity, and then slowly added. 5. Water ripple (bubble) phenomenon The main reasons: ①the water content in the ink is too high; ② the ink in the ink tank is low; ③ the stirring speed of the ink tank is too fast; ④ the viscosity of the ink is too low. Solution: ①Add defoamer or ethanol to increase the viscosity of the ink; ②Increase the amount of ink in the ink tank properly, increase the ink tank, so that the printing plate can be more immersed in the ink; ③Reduce the stirring speed of the ink tank; ④ Add an ink transfer roller or add an ink stirring rod in the ink tank. 6. Phenomenon increase Gravure water-based inks have a slow drying speed and are prone to increase dots, especially when printing small text and lines, the small text and lines tend to become thick. In this regard, fine text and lines need to be thinned during plate making. Pu Evening Bag,Silver Evening Bag,Rose Gold Evening Bag,Gold Evening Clutch GUANGZHOU KOEDS LEATHER LIMITED , https://www.kodes-bag.com