| 摘要 |
PURPOSE:To determine whether a fill-in is present or not by ejecting ink drops directly on a sheet-like matter for testing from ink jet nozzles and reading the printed state with an image sensor optically. CONSTITUTION:In an ink jet printer 1, print liquid is ejected from ink jet nozzles 9, 10, 11, 12 on a sheet-like matter 2 such as cloths to be conveyed by a conveyer 3 based on an image data so as to print desired patterns. On a side part of the sheet-like matter 2 on which printing will be actually performed, a fill-in detecting area where a sheet-like matter 18 for testing is to be arranged is provided. The ink is ejected also on the sheet-like matter 18 for testing from the ink jet nozzles. Also, a sensor 20 for detecting optically the printed state of the sheet-like matter 18 for testing and a fill-in detecting device for detecting fill-in of also the nozzles based on a difference in quantity of light between a printing part and a non-printing part in the output of the sensor 20 are provided. Thus, fill-in of the nozzles can be detected regardless of type of head and kind of ink. |
