HP LaserJet 6p/mp Service Manual - Page 139

Paper curl Paper curl is inherent to the laser printing processes, and occurs when paper is subjected to heat. Paper curl tends to relax as the paper cools while resting on a flat surface. The specification for maximum paper curl when the paper is lying flat before print is 5 mm (0.2 inches). Although paper curl cannot be totally eliminated, some steps can be taken to lessen its impact, as suggested in the following table. Table 7-5 Paper curl troubleshooting Possible causes Recommended action Paper path Try using the front output slot to shorten and straighten the paper path. Paper surface The recommended printing surface of the page is usually marked on the end of a ream of paper by a small arrow and the phrase "print this side first." If the incorrect side was face up, turn the paper over. Load paper into the Paper Input Tray with the recommended printing surface facing the front of the printer. Paper storing and handling Over time, paper assumes the characteristics of its storage environment. (In a humid environment, paper absorbs moisture. In a dry environment, paper loses moisture.) Paper with higher moisture contents will tend to curl more. Evaluate the storage conditions of the paper. Paper type All paper is manufactured differently (texture, moisture content, drying processes, composition, etc.). Change the type of paper being used and reevaluate the paper if curl results. EN Troubleshooting checks 137