4.13.99
Two advancements are UV curing technology are head reduction and lower costs.
Smaller diameter UV-producing lamps have less surface area operating at a high temperature
and sending infrared radiation (heat, IR) to the printing substrate. Heat will change the
size of the printing substrate and equipment, thus effecting registration. IR filters
which block out heat but pass the UV radiation can be placed between the lamp and the
substrate. Heat absorbing dichroic coatings can be applied to the lamp reflector which
also reflect UV. Cooler UV lamps are also available which emit more UV at a lower
temperature, thus emitting less IR.As more UV inks and coatings are used, prices are
decreasing.
New photo-initiators are anticipated which require less UV energy, thus leading to less
heat, shorter cure times and faster web speeds.
Author: Michael DeRosa
Source: FLEXO, March, 1999, p. 12-16. |
