Patent ID: 7458666

Claim:
A method for charging a liquid into a supply line defined in a liquid ejection apparatus, the supply line supplying the liquid from a liquid retainer retaining the liquid to a nozzle ejecting the liquid, the supply line including a tubular passage and a plurality of enlarged portions that communicate with the tubular passage, the liquid ejection apparatus having suction means that draws gas or liquid from the supply line through the nozzle, the method comprising: a first suction step of performing suction by the suction means with a portion of the supply line held in a blocked state at a predetermined position, and then releasing the blocked portion of the supply line, thereby discharging a bubble from an upstream one of the enlarged portions; and a second suction step of performing the suction by the suction means, after the first suction step, with the portion of the supply line held in the blocked state at the predetermined position until obtaining a maximum negative pressure smaller than a maximum negative pressure of the first suction step in the supply line, and then releasing the blocked portion of the supply line after completing the suction by the suction means, thereby discharging a bubble from a downstream one of the enlarged portions.