PURPOSE: To retain the desired quality of printing irrespective of the high density of the printing by providing a working means variable for a predetermined parameter which affects the curing speed of each ink dot, a density detecting means for detecting the density of ink dots, and a control means for controlling the working means.

CONSTITUTION: An ink-jet printer 3, which carries out printing on a medium 2 to be printed, is provided with: a working means 5 which works according to the magnitude of variables for a predetermined parameter that affects the curing speed of each ink dot with respect to ink dots 4 adhering onto the medium 2; a density detecting means 6 for detecting the density of the ink dots 4; and a control means 7 for controlling the magnitude of variables according to the density, in order to fix the ink dots on the medium 2. In the case of hot-metal ink, the predetermined parameter is applied as the cooling speed of the ink dots, the working means 5 is used as a blower to send air at a variable air volume onto the medium 2 to which ink dots adhere, and the control means 7 controls the air volume from the blower.