US Patent 9139012 Ink filling apparatus and ink filling method

The present invention enables a suitable ink filling state of an ink tank to be achieved by setting ink filling conditions taking prevention of ink leakage during unsealing of an ink supply port into account. An ink tank includes a first storage chamber formed in the ink tank to store an ink absorber, and a second storage chamber also formed in the ink tank to substantially form a closed space except for a communication section communicating with the first storage chamber. After the pressure in the ink tank is reduced to a target pressure through an atmospheric communicating port, the ink tank is internally filled, through an ink supply port, with a target filling amount of ink associated with the target pressure.