| abstract |
(57) [Problem] To improve the print quality such as OD and to achieve high-speed fixation in ink jet printing, regardless of whether a print medium or a plain paper on which a coat layer is formed is used. A plain paper mode for printing on plain paper and a special medium mode for printing on a special medium on which a coat layer is formed are provided. B using both self-dispersible pigments and dyes as color materials from k Then, the k ink is ejected, and then the treatment material having high solubility and insolubilizing the color material is ejected from the head 101S. On the other hand, in the special medium mode, only the Bk ink is discharged from the head 101Bk, and the processing liquid is not discharged from the head 101S. |