Zone of invisible radiations beyond the violet end of the spectrum of visible radiation.

Of or relating to the range of radiation wavelengths from approx. 4,000 angstroms, just beyond the violet in the visible spectrum, to approx. 40 angstroms, on the border of the x-ray region.

Those light rays, outside the visible spectrum at its violet end, that have a chemical effect upon the dried films of finishing materials.

That part of the electromagnetic spectrum lying beyond the blue end of the visible spectrum; it is the primary cause of pigment failing. Ultra-violet curing: polymerisation effected by the presence of ultra-violet. The drying mechanism of inks designed to cure by ultra-violet irradiation.