| 摘要 |
PURPOSE:To save an ink, to reduce a device in size and to achieve a low run ning cost by a method wherein a volume of an ink passage of a first record head is greater than that of the other record head and a passage resistance, number of nozzles, a diameter or a length of a nozzle block communicating to the ink passage is greater than that of the other record head. CONSTITUTION:In a record head wherein number of nozzles of black is two times that of the other color, cross sectional areas of the nozzles are two times of those of the other so that an ink flowing rate of black is two times that of the other. When comparing volumes shown by inclination lines 14-17 with each other, a suction requirement amount of the black is greater than that of the other and that of yellow is the smallest. For example, in the case where the suction requirement amount of a tank and nozzles for yellow is 0.4cc, that for black is 0.2cc. When the suction recovery for recovering the printing defect is performed, a negative pressure whereby 0.2cc of the suction requirement amount for yellow is sucked is applied to a cap 701, 0.2cc of the suction requirement amount is sucked in the case of yellow and 0.2ccX2=0.4cc of the suction requirement amount is sucked in the case of black. Thereby, it is possible to obtain 0.4cc of suction requirement amount in the case of black. |
