UV Ink Definition And Principle

UV ink is an ink that does not use solvents, has fast drying speed, good gloss, bright colors, good water resistance, solvent resistance and wear resistance. UV ink has become a more mature ink technology, and its pollutant emissions are almost zero. According to statistics, the annual output of UV inks is about 16,000 tons in Japan, about 18,000 tons in Europe, and about 19,000 tons in North America. It should be noted that the water-based UV ink in the UV ink is a new research direction in the field of UV ink. Because the viscosity of prepolymers in ordinary UV inks is generally very large, it needs to be diluted with reactive diluents, and the diluent acrylate compounds used have varying degrees of skin irritation and toxicity. Therefore, low viscosity prepolymers and low At the same time as the toxic diluent, another development direction is to study water-based UV inks, that is, water and ethanol are used as diluents. Water-based UV inks have been successfully developed and applied in some printing companies.

Principle: UV ink has the characteristic of selective absorption of UV light. Drying is affected by the total energy of the UV light source and the distribution of light energy at different wavelengths. Under the irradiation of UV light, the UV ink photopolymerization initiator absorbs photons of a certain wavelength and excites to an excited state, forming free radicals or ions. Then, through the intermolecular energy transfer, the polymerized prepolymer and the light-sensitive monomer and polymer are brought into an excited state, resulting in a charge transfer complex. These complex particles are continuously cross-linked and polymerized, solidifying into a film.