A paper web defect characterized by either a raised welt, band, or wrinkle located near the outer portion of the roll and run in the machine direction, caused by cross-grain expansion of the outer layers of paper due to absorption of moisture. Moisture welts result when a roll is exposed to higher relative humidity or to warm air. Moisture welts typically only affect the outer layers of the paper roll, and can usually be cut off. Running a roll containing moisture welts through the press will cause misregister.
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