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TEMPERATURE /
HUMIDITY CONDITIONING
In striving to achieve
maximum quality out of a printing project, paper should always be
ordered with enough lead time to allow it to acclimatize to the
environment of the pressroom. Differences in temperature and
humidity between the pressroom and the paper can cause problems that
may prove difficult to overcome. Paper unwrapped while cold will
quickly become wavy because the paper’s low temperature chills the
air, and the unprotected edges of the paper rapidly take on moisture.
As the temperature of the paper rises, this additional moisture will
in part be given off, but in the process the moisture content of the
paper at the edges will not return to the same moisture content as
the balance of the sheets. Waviness created by unwrapping cold skids
in a warm pressroom can not be entirely removed.
In addition, we highly
recommend the practice of covering the stock with a skid cover
between passes. This creates a much smaller environment that the
paper can react to and allows the center and edges of the sheet to
equalize.
VOLUME OF PAPER
SKIDS AND CARTONS
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Degrees
F
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Degrees
C
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6 Cubic Feet
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12 Cubic Feet
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24 Cubic Feet
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48 Cubic Feet
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96 Cubic Feet
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10°
15°
20°
25°
30°
40°
50°
60°
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5.6°
8.3°
11.1°
13.9°
16.7°
22.2°
27.8°
33.3°
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5 hrs.
9 hrs.
12 hrs.
15 hrs.
18 hrs.
25 hrs.
35 hrs.
54 hrs.
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8 hrs.
14 hrs.
18 hrs.
22 hrs.
27 hrs.
38 hrs.
51 hrs.
78 hrs.
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11 hrs.
16 hrs.
23 hrs.
28 hrs.
35 hrs.
48 hrs.
67 hrs.
100 hrs.
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14 hrs.
19 hrs.
26 hrs.
32 hrs.
38 hrs.
54 hrs.
75 hrs.
109 hrs.
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15 hrs.
20 hrs.
27 hrs.
34 hrs.
41 hrs.
57 hrs.
79 hrs.
115 hrs.
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Hours paper should stand
unopened in order to come in balance with room temperature.
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Difference in temperature of
room in which paper is to be opened and the paper on arrival.
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NOTE: To determine cubic feet
of volume, multiply length x width x height in inches and
divide by 1728.
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