| 摘要 |
PROBLEM TO BE SOLVED: To accurately detect ink concentration of ink which is supplied to an inkjet head. SOLUTION: A concentration detection part 112 of a concentration detector 110 is provided midway through a supply passage 102. A cleaning liquid is made to flow into the ink passage 102 so that the ink concentration in the cleaning state of the supply passage 102 can be detected by the detection part 112. A detection value in the cleaning state is an ink concentration which is caused by coloring material particles fixedly attached to an inner wall of the supply passage 102. A concentration correction part 114, wherein the detection value in the cleaning value is stored as a baseline, corrects a detection value in an operating state, detected by the detection part 112, in accordance with the baseline, when the inkjet head is operated, that is, when the ink is supplied to the ink passage 102. Thus, the accurate ink concentration, which is subjected to the correction of a concentration content caused by the coloring material particles fixedly attached to the inner wall of the supply passage 102, is obtained. COPYRIGHT: (C)2005,JPO&NCIPI |
