Appendix
Appendix-4
Basis Weight
Basis weight is the weight of a standard quantity of paper. In the traditional system the standard
quantity is a ream consisting of 500 sheets measuring 17 × 22 inches each. In the metric system the
standard quantity is 1 square meter.
Paper that is too light or too heavy can cause misfeeding, jams, and premature wear of the
machine. Uneven paper weight can cause multiple feeds, print defects, poor toner fusing, blurring,
and other print quality problems. The proper weight is 60 to 105 g/m² for the paper cassette, and 60
to 163 g/m² for the MP tray.
Thickness (Caliper)
Thick paper is referred to as high-caliper paper and thin paper as low-caliper paper. The paper used
with the machine should be neither extremely thick nor extremely thin. If you are having problems
with paper jams, multiple feeds, and faint printing, the paper you are using may be too thin. If you
are having problems with paper jams and blurred printing the paper may be too thick. The proper
thickness is 0.086 to 0.110 mm (3.4 to 4.3 mils).
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 appearance, feed ability, curl, electrostatic properties, and toner fusing
characteristics.
The moisture content of the paper varies with the relative humidity in the room. When the relative
humidity is high and the paper absorbs moisture, the paper edges expand, becoming 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 machine 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
machine. All paper used in the machine should be long grain.
Other Paper Properties
Porosity: Refers to the density of the paper structure; that is, to how openly or compactly the fibers
are bonded.
Stiffness: Limp paper can buckle inside the machine, while paper 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 direction. The paper should be loaded so that
the natural curl is downward, to counteract the upward curl imparted by the machine. 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.
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