Oce WP36/50, Руководство по эксплуатации

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Chapter 2 Handling Paper
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Moisture Content
Moisture content is defined as the percent ratio of moisture to
the dry mass of the paper. Moisture can affect the paper’s ap-
pearance, feedability, curl, electrostatic properties, and toner
fusing characteristics.
The moisture content of the paper varies with the relative hu-
midity in the room. When the relative humidity is high and
the paper absorbs moisture, the paper edges expand, becom-
ing wavy in appearance. When the relative humidity is low
and the paper loses moisture, the edges shrink and tighten,
and print contrast may suffer.
Wavy or tight edges can cause misfeeding and alignment
anomalies. The moisture content of the paper should be 4 to
6%. To ensure the proper moisture content, it is important to
store the paper in a controlled environment. Some tips on
moisture control are:
• Store paper in a cool, dry location.
• Keep the paper in its wrapping as long as possible. Rewrap
paper that is not in use.
• Store paper in its original carton. Place a pallet, etc., under
the carton to separate it from the floor.
• After removing paper from storage, let it stand in the same
room as the printer for 48 hours before use.
• Avoid leaving paper where it is exposed to heat, sunlight,
or damp.
Paper Grain
When paper is manufactured, it is cut into sheets with the
grain running parallel to the length (long grain) or parallel to
the width (short grain). Short grain paper can cause feeding
problems in the printer. All paper used in the printer should
be long grain.
Other Paper Properties
Porosity:
Refers to the density of the paper structure; that is,
how openly or compactly the fibers are bonded.
Stiffness:
Limp paper can buckle inside the printer, while pa-
per that is too stiff may bind. Either way the result is a paper
jam.
Curl:
Most paper has a natural tendency to curl in one direc-
tion. The paper should be loaded so that the natural curl is
downward, to counteract the upward curl imparted by the
printer. Printed sheets will then come out flat. Most paper
also has a top and bottom surface. Loading instructions are
usually given on the paper package.
If the paper is considerably curled in one direction, e.g. when
the paper was used to print on one side, try to roll the paper
in the opposite direction to counteract the curl. Printed sheets
will then come out flat.
Electrostatic properties:
During the printing process, the pa-
per is electrostatically charged to attract the toner. The paper
must be able to release this charge so that printed sheets do
not cling together in the output tray.
Whiteness:
The contrast of the printed page depends on the
whiteness of the paper. Whiter paper provides a sharper,
brighter appearance.
Quality control:
Uneven sheet size, corners that are not
square, ragged edges, welded (uncut) sheets, and crushed
edges and corners can cause the printer to malfunction in var-
ious ways. A quality paper supplier should take considerable
care to ensure that these problems do not occur.
Packaging:
Paper should be packed in a sturdy carton to pro-
tect it from damage during transport. Quality paper obtained
from a reputable supplier is usually properly packaged.
NOTE