The Printing Process
Printing Services has three offset presses available
for high quality printing, capable of printing sizes up to a maximum 20
½" X 29" sheet size.
The offset printing process works by transferring the
image (file or camera) to a metal photoreceptive plate. The metal plate,
when placed on the press, attracts ink to the image area and water to
the blank areas. The image transfers from the inked metal plate to a rubber
blanket, which in turn transfers the image to a sheet of paper. The term
"offset" is used because the metal plate never comes in direct
contact with the paper. Because the plate does not come in direct contact
with the paper, it lasts longer and can be re-used. When the image transfers
from the rubber blanket to the paper, the softer surface allows better
ink coverage on textured paper.
The largest offset press at Printing Services is called
a color perfector and will print one color of ink (can be two different
colors) on both sides of the sheet simultaneously or two colors of ink
on one side of the sheet. Maximum sheet size is 20 ½ X 29".
Often the image will be repeated on a larger sheet several times to save
on cost and reduce the number of times the sheet travels through the press.
The finished sheets are trimmed, scored, folded and
bound in the Printing Services bindery area once the job is complete and
the ink has dried. Some specialty finishing processes like embossing,
die cutting and foil stamping are handled off-campus by specialized vendors.
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