Patent ID: 7665821

Claim:
An inkjet printer comprising: a print head that includes a nozzle and ejects ink through the nozzle; a maintenance unit that performs a maintenance operation to recover an ejection state of the nozzle, the maintenance operation including at least one of ejecting the ink through the nozzle and sucking the ink from the nozzle; a sealing unit that selectively exposes and seals the nozzle; a first timer unit that measures a sealing time when the sealing unit seals the nozzle; a second timer unit that measures an exposing time when the sealing unit exposes the nozzle; a dryness obtaining unit that obtains a dryness level of the nozzle based on the sealing time and the exposing time; a limit level storing unit that stores a predetermined dryness level as a limit level; and a control unit that activates the maintenance unit when the obtained dryness level is equal to or above the limit level and further comprising: a drying coefficient storing unit that stores a plurality of drying coefficients in association with the exposing time; and a drying coefficient obtaining unit that obtains one of the drying coefficients corresponding to the exposing time from the drying coefficient storing unit, wherein the dryness obtaining unit obtains the dryness level based on the obtained drying coefficient and the sealing time.