Banding is a common printing defect characterized by light or dark lines in an image in the direction of the printing. In the case of inkjet imaging it is caused by a jet or printhead that is not properly aligned, inoperative, or incorrectly indexed. The usual cause of banding is clogged or partially clogged nozzles in the printhead. To clear banding, you usually need to clean the printhead nozzles. Some inkjet printers have printheads on the cartridges, some are in the printers. Usually, HP, Lexmark and Dell have printheads on the cartridges, whereas Canon, Epson, Brother and Kodak have printheads inside the printers. The printers that have printheads inside the printers usually always have menu features to run "print head cleaning" cycles. On such machines, you should run cleaning cycles until banding clears up. On other types (such as most HP, Lexmark, Dell), you can sometimes unclog the printheads on the cartridges by blotting the cartridge printheads onto a damp paper towel (dampened by water, alcohol, or print head cleaning solution). To avoid banding, its best to not let your cartridge or printer idle for prolonged periods of time. Print at least 1 page per week, and take your cartridges for a professional refill soon after they empty (or better yet - just before they completely empty) so as to protect the integrity of the printheads as much as possible.
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