Patent ID: 6984009

Claim:
An ink jet printing apparatus for forming an image by ejecting ink from a print head onto a print medium, wherein the print head has arrayed in nozzle columns at least two kinds of nozzles that eject different volumes of ink supplied from a common ink chamber, the ink jet printing apparatus comprising: preliminary ejection means for performing ink ejections, not involved in the formation of an image, from the nozzles of the print head; suction means for sucking out ink from the print head through the nozzles of the print head; and control means for causing said suction means to suck out ink from the print head and then said preliminary ejection means to perform the ink ejections, wherein, in an ink ejection operation by said preliminary ejection means following the suction of ink by said suction means, said control means causes the nozzles of the same kind to eject ink simultaneously and controls to set the number of ejections from the nozzles with a large ink ejection volume to be greater than the number of ejections from the nozzles with a small ink ejection volume, and wherein the print head has different nozzle columns for different ink colors, and said preliminary ejection means causes the same kind of nozzles in the nozzle columns of each ink color to perform an ejection operation at a time.