UV ink is a kind of ink without solvent, fast drying speed, good gloss, bright color, water resistance, solvent resistance and abrasion resistance. At present, UV ink has become a more mature ink technology, and its pollutant emission is almost zero. According to statistics, the annual output of UV ink is about 16,000 tons in Japan, 18,000 tons in Europe, and 19,000 tons in North America. It should be noted that the water-based UV ink in UV ink is a new research direction in the field of UV ink. Because the viscosity of the prepolymer in ordinary UV inks is generally very large, it needs to be diluted with a reactive diluent, and the currently used diluent acrylate compounds have different degrees of skin irritation and toxicity, so low-viscosity prepolymers and In addition to low-toxic diluents, another development direction is to study water-based UV inks, that is, water and ethanol are used as diluents. At present, water-based UV inks have been successfully developed and applied in some printing companies. UV (ultraviolet light curing) ink refers to the use of ultraviolet light of different wavelengths and energy to polymerize monomers in the ink binder into polymers under ultraviolet irradiation, so that the ink can be filmed and dried. UV inks are also inks. As inks, they must have brilliant colors (except in special cases), good printability, and suitable curing and drying rates. At the same time, it has good adhesion, and has the characteristics of wear resistance, corrosion resistance and weather resistance.
Als LED-UV ink is a UV-curable solvent-free ink. The principle of drying is the same as that of UVLED varnish. After the photosensitive material receives ultraviolet photons, the prepolymer and diluent are polymerized and light-cured. The de-reaction time is very short, about 0.1-0.2s. After the reaction, a cured ink film is formed, and there is no volatile and penetrating substances during the reaction. It is characterized by quick drying, good film gloss, and resistance to friction.
The principle of ordinary ink drying is mainly oxidation, penetration, and solvent volatilization in the ink. These three processes all take a long time. It takes 20 hours to dry when printed with 90%-dot screen normal offset printing ink.