UV curing ink

In recent years, the use of UV-curing inks and UV-curable adhesives has increased, both in the screen printing industry and the offset printing industry, as well as in other industries that require rapid curing. As we all know, UV curing ink, UV curing glue has good gloss, strong three-dimensional effect, no harmful solvent evaporation and other advantages, especially in the drying of ink, UV light solid ink can be cured instantly under ultraviolet light, avoiding the traditional The solvent-based inks have long drying cycles, large floor space, and other shortcomings, greatly improving work efficiency and quality. After curing, UV light-curable inks need to be cured by UV light curing equipment. The main factors influencing the quality of UV light curing include the wavelength, energy of the UV lamp, the speed of the conveyor belt, the UV curing principle of the UV machine cooling system, the UV curing machine and relevant technical parameters:

A: Ultraviolet (UV) curing principle: adding photoinitiator (or photosensitizer) to specially formulated resin, after absorbing high-intensity ultraviolet light in ultraviolet (UV) light curing equipment, producing active free radicals, thereby initiating polymerization The cross-linking and grafting reactions allow the resin to convert from liquid to solid within seconds.

II: Ultraviolet (UV) Curing Machine: Currently, the LED curing has replaced the curing of mercury lamps in the industry. The LED curing machine is different from the traditional high-pressure mercury lamp curing equipment; the UV light generated by the traditional curing machine looks bright and the heat is high. Very high, in fact, its spectrum is very wide, and only a part of the energy is actually in the ultraviolet spectrum of effective curing. A large part of it is in the visible light section (stall light) and generates heat, causing serious damage to the operator's eyes. And easy to heat deformation of the workpiece processing, the use of LED point light source irradiation, emits high-purity 365nm monochromatic ultraviolet light, it belongs to the cold light source; workpiece temperature rises only about 3 degrees, the workpiece will not be deformed, its energy is highly concentrated in A UV spectral segment with effective curing is the main reason why the UV-LED spot light has only about 200mw of UV light intensity, but its practical use effect is comparable to that of a high-pressure mercury lamp with a light intensity of 1000-2000mw. Usually reduces the cure time to 0.5 to 5 seconds

Effect of related parameters on curing quality

One: The power of UV curing machine: The power required for general UV light curing ink is 80-120w/cm. Excessive light and solid energy will cause the embrittlement of the ink, and the photo-solid energy is too low to reach the photo-curing effect.

Second: suction device: UV curing machine at the same time, it will also generate a lot of heat, so that the body's temperature continues to increase, light curing machine is equipped with a suction device above the UV curing machine chassis, and the curing process through the exhaust pipe The ozone generated in the room is discharged outside to achieve the purpose of cooling down.