| UCR
(Under Colour Removal) |
The
removal of cyan, magenta and yellow from neutral colour areas (primarily
shadow tones) and their replacement with black. |
| UGR |
Under
colour Grey Removal. |
| Ultra-Violet |
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. |
| Underwriter's
Laboratories (U.L.) |
A
non-profit corporation operating in the public interest, endeavouring
to maintain safety standards in electrical equipment and appliances.
Licensed use of its label requires close adherence to their specifications. |
| Uniform
Chromaticity Scale Diagram |
Any
one of a variety of transformations of the CIE chromaticity diagram
on which all pairs of just noticeably different colours of equal
luminance are represented by pairs of points separated by nearly
equal distances. |
| Uniform
Colour Scale |
A scale wherein the units of colour difference that are judged to
be equally different, are separated by nearly equal distances. |
| Uniform
Colour Space |
Three-dimensional
space wherein all pairs of colours judged to be equally different,
are separated by nearly equal distances. |
| UV
Resistant |
Combats
degradation by ultra violet; i.e. maintains original characteristics
longer than non-U.V. resistant materials. |
