What are the determining factors for UVLED deep curing?read count [195] release time：2020-01-14 20:00:00
UVLED What are the determinants of deep curing? UVLED As a common curing equipment, light curing machine Its curing principle refers to the UV coating passing through U VLED light source After irradiation, the photoinitiator is triggered, thereby generating free radicals or ions, and these free radicals or ions cross-link with the double bonds in the prepolymer or unsaturated monomer to form monomer genes. These monomer genes start a chain reaction to generate polymer solid ion molecules, which is a complete curing process. Compared with traditional UV mercury lamps, the advantages are quite obvious, such as fast curing speed, No need to replace lamps, Environmental protection and safety, Easy to operate, cold light source, etc.
Influence Several major factors for UVLED deep curing:
1. Influence of working environment
When the viscosity of UV coating changes greatly due to temperature, the room temperature should be adjusted, generally 15-25°C is more suitable, and attention should be paid to not being exposed to direct sunlight during curing.
2. The influence of curing distance
The UV lamp generally has a distance of about 10-15mm depending on the curing substrate. The curing distance must be appropriately adjusted according to the base material, coating, and irradiation power of the UVLED lamp.
three, UV light curing Effect of speed
Depending on the substrate, coating, curing distance, etc., adjust the equipment curing speed appropriately. If the curing speed is too fast, the UV coating on the surface of the substrate will become sticky or dry on the surface but not inside; if the operation speed is slow, the surface of the substrate will age.
4. The influence of UVLED energy
The main condition for deep curing by ultraviolet radiation is that the molecules must absorb light quanta with sufficient energy to become excited molecules and decompose into free radicals or ions, allowing unsaturated organic matter to undergo chemical reactions such as polymerization, grafting, and cross-linking to achieve the purpose of curing. The UVLED energy of the photoinitiator in the supplied UV coating exceeds or is insufficient for the required energy.
1. I don’t know what photoinitiator is needed. UVLED cold light source Energy, such as blindly excessive supply, not only wastes energy, but also causes negative effects of excessive curing, such as explosion and anti-curing reactions.
2. When the UVLED energy is insufficient, the UVLED energy must be moderate, that is, neither excessive nor insufficient, to avoid complete curing.
5. The influence of UV coating thickness
The thickness of the UV coating plays a key role in the effect of UV curing. If the coating is too thick, the drying time will be relatively long under the irradiation of the same power light source. On the one hand, it will affect the drying of the UV coating. On the other hand, the surface temperature of the substrate will be too high, resulting in substrate deformation. If the coating is too thin, the surface gloss of the product will be poor. In addition, the thickness of the UV coating needs to be appropriately formulated under different conditions such as hue, temperature, curing speed, and substrate surface.
