Ultraviolet light is invisible light, ultraviolet lamp can see purple light is because in the special formulation of the resin to add photoinitiators (or photosensitizers), after absorption of ultraviolet (UV) light curing equipment in the high-intensity ultraviolet light, the production of reactive radicals or ionic radicals, which triggers polymerization, crosslinking and grafting reactions.
To make the resin (UV coatings, inks, adhesives, etc.) in a few seconds (varying) from the liquid state into a solid state. (This change process is called "UV curing"). UV light radiation physical properties similar to visible light, are linear, its penetration is far less than visible light, the shorter the wavelength, the worse the penetration, so the UV curing is mainly used in the light can be directly shot to the epidermal surface or light transmittance of the inner layer of the curing is better.
Expanded
Ultraviolet light is a low-energy electromagnetic wave, because it has a good bactericidal effect and is widely used in medical, health care, food industry, pharmaceutical industry and other sectors. But how to correctly use the ultraviolet lamp to ensure its sterilization effect, extend the service life of the lamp, to avoid injuries, is the first requirement of each operator to master, now talk about a few years of experience in the use of.
Ultraviolet irradiation, so that the bacterial protein photolysis, denaturation, bacterial amino acids, nucleic acids, enzymes were destroyed and died. At the same time, when the ultraviolet light passes through the air, it ionizes the oxygen in the air and produces ozone, which strengthens the bactericidal effect.
Baidu Encyclopedia - Ultraviolet Lamps