| Obliteration |
The
power of an overprint to hide completely the colour underneath;
also sometimes referred to as "obliterating power" or
"opacity". |
| Observer,
Standard |
The
spectral response characteristics of the average observer defined
by the CIE. Two such sets of data are defined, the 1931 data for
the 2-visual field (distance viewing) and the 1964 data for the
annular 10-visual field (approximately arms length). |
| ODC
(On-Demand Colour) |
This
term typically refers to short run colour printing. These processes
include ink-jet, electrostatic and direct-to-press. |
| OEM |
Original
Equipment Manufacturer. |
| Off
Contact |
The
preset distance between the screen and the substrate to be printed. |
| Offset |
An
unintentional or faulty transfer of wet ink from a printed sheet
to another surface in contact with it. Also called setoff. |
| |
The
transfer of ink from Plate to object with conventional pad printer. |
| Offset
Printing (Offset Lithography) |
A
common printing process that makes prints by transferring ink from
a flat plate to a rotating "blanket" that contacts the
paper. |
| Oilbound |
Refers
to an ink system whose vehicle is oily in nature. Colloquially (but
not accurately) used to describe ink thinnable with white spirit. |
| Opacity |
The
measure of the amount of light that can pass through a material.
Also, the property of a film that prevents "show through"
of dark printing or marks on a substrate (media). "Hiding power" |
| Opaque |
Impenetrable
by light; neither transparent nor translucent. |
| Optical
Character Recognition (OCR) |
A
technology that can recognise letters from a scanned image and convert
them into ASCII characters to be saved as an editable text file. |
| Optical
Resolution |
The
maximum physical resolution of a device. Optical resolution provides
better quality than interpolated resolution of the same number,
which uses software to create additional image information. |
| Orange
Peel |
A
defect which causes the ink film to dry to a glossy but uneven film
like that of the skin of an orange. Considered to be due to lack
of flow. |
| Over
laminate |
A
protective clear film that extends an image's outdoor life and enhances
its visual quality. |
| Over
laminating |
Application
of a clear film to a graphic for the purpose of protection or to
enhance the graphic quality. |
| Overprint/Overvarnish |
An
overprint results when one ink or varnish is printed on top of another
ink or varnish. |
| Overprinting |
Printing
one ink or tint build over another, most commonly for trapping purposes. |
