Patent ID: 7708373

Claim:
An ink-jet head which discharges a plurality of different color inks onto a recording medium, comprising a plurality of nozzle groups which jet the inks onto the recording medium respectively, and each of which is formed by a nozzle row formed by a plurality of nozzles arranged in a predetermined direction that is parallel to a paper feed direction; wherein each of the nozzle groups has a high density portion formed therein and positioned at a central portion thereof in the predetermined direction; two low density portions which are positioned at both sides in the predetermined direction, respectively, of the high density portion and in which the nozzles are arranged in the predetermined direction at a spacing distance greater than a spacing distance at which the nozzles are arranged in the high density portion; and two nozzle groups, among the plurality of nozzle groups, are arranged at positions shifted from each other in the predetermined direction such that at least a part of the high density portion of one of the two nozzle groups overlaps with a part of the low density portions of the other of the two nozzle groups.