Patent ID: 7441854

Claim:
An ink jet printing apparatus capable of printing an image on print medium by using an ink jet print head comprising a plurality of nozzles which are arranged in a plurality of lines and from which ink can be ejected, relative movement between the ink jet print head and the print medium being effected in a direction crossing the nozzle lines while allowing the ink jet print head to eject ink, wherein in the ink jet print head two sets of a predetermined number of nozzles, in a joining portion of respective adjacent nozzle lines, overlap each other in the direction crossing the nozzle lines, and relative positions of the adjacent nozzle lines are set depending on the amount of misdirection of ink ejected from the nozzles located in the joining portion, wherein the ink jet printing apparatus further comprises control means for selectively using overlapping nozzles in the joining portion, and wherein the control means sets a reference direction from one end of one of the adjacent nozzle lines toward the other end, and controls the overlapping nozzles so that a print density of dots formed using one of the nozzle lines in the joining portion gradually decreases in the reference direction, while the print density of dots formed using the other nozzle line in the joining portion gradually increases in the reference direction.