INKJET PRINTING APPARATUS AND INKJET PRINTING METHOD

An inkjet printing apparatus 1 includes: a casing 90; a transport mechanism 10 that transports a recording medium 9 inside the casing 90 along a prescribed transport path; an ejection head 21 arranged inside the casing 90 and ejecting ink to the recording medium 9; a process chamber 40 having an inlet 40A and an outlet 40B arranged downstream from the ejection head 21 and for passage of the recording medium 9, the process chamber 40 communicating with the interior of the casing 90 through the inlet 40A; an irradiation unit 70 that irradiates the recording medium 9 inside the process chamber 40 with an ultraviolet ray; an inert gas supplier 50 that supplies an inert gas into the process chamber 40; and an air discharge part 60 that discharges atmosphere inside the process chamber 40 to the outside of the process chamber 40 and to the outside of the casing 90. An internal pressure in the process chamber 40 is less than an internal pressure in the casing 90.