To solve such a problem that a large amount of liquid is required for cleaning, it takes much time to replace the liquid, and the non-discharge occurs due to bubble mixture into a nozzle.

An ink cleaning filling unit 61 includes: an ink bottle 63 where ink is enclosed and sealed from which a dissolved gas is removed in the ink to be filled; and a pressurizing gas cylinder 62 where gases are stopped up, such as air and nitrogen for feeding the ink by pressure (pressurized solution sending) to a head unit 1. When liquid in the head 1 and a tank 4 is replaced, the insides of the head 1 and the tank 4 are cleaned and the liquid is replaced and filled while the following are repeated: a compressed gas is supplied into the tank 4 to drain the liquid in the tank 4 out; the liquid in the ink bottle 63 is supplied to the tank in the state where the liquid in the tank 4 is not fully drained out; and the tank 4 is filled with the supplied liquid.