UV ink has an important impact on the use of UV curing equipment, but in the process of use, UV ink will inevitably have many problems. Today, I will introduce you to UV ink and what problems there will be during use.
1. What happens if the UV ink is too dry?
There is a theory that UV ink will become harder and harder when exposed to too much ultraviolet light. When people are printing, the hard ink film is first painted with a layer of ink, and then the second drying is performed, which will reduce the adhesion between the upper and lower inks.
Another argument is that excessive curing will cause photo-oxidation of the UV ink surface. Photooxidation can destroy the molecular chains on the surface of UV inks. If the molecular chains on the ink film are degraded or destroyed, the bonding strength of the ink film and other ink layers will decrease. Excessive curing not only has poor elasticity, but also easily embrittles the surface.
2. When using UV ink, will the polycarbonate film turn yellow?
When the ultraviolet band is less than 320 nanometers, ultraviolet rays will become very fragile. The breaking of the molecular chain makes the surface of the film yellow, and the plastic molecular chain absorbs ultraviolet light energy and generates free radicals. Free radicals react with oxygen in the air to change the appearance and physical properties of plastics.
3. What should I do if the surface of polycarbonate turns yellow?
UV ink printing with UV curing equipment can effectively reduce the yellowness of the printed surface, but it is impossible to completely eliminate it. Adding iron or gallium to the UV lamp tube of UV curing equipment can effectively reduce the release of short-wavelength ultraviolet light. In addition, the proper curing of various colorants can effectively shorten the UV exposure time of the polycarbonate film and reduce the possibility of its discoloration.
4. Why do some UV inks cure faster than others?
The UV inks of UV curing equipment are generally made according to the characteristics of specific carriers and the special requirements of specific uses. From the chemical principle, the faster the ink curing speed, the worse the elasticity after curing. It is conceivable that after the ink is cured, the ink molecules will undergo a cross-linking reaction. If this type of molecule forms multiple forked molecular chains, the ink cures quickly, but the elasticity is small; if the molecular chains are less and do not branch, the ink cures slowly but is flexible, which is why the ink of this device cures more than other curing devices The important reason for fast is a unique advantage of it, and because this advantage enables it to be widely used in industrial production, it is favored by major manufacturers.
Shenzhen Height-LED specializes in the production of uvled curing equipment, and can customize suitable uvled curing systems for customers. Welcome to consult.