Patent ID: 7581810

Claim:
A maintenance method of performing a maintenance of an inkjet recording apparatus comprising a recording unit having at least two recording element substrates, each recording element substrate having at least one recording element group configured to discharge a liquid, the method comprising: counting, for each of the two recording element substrates, a number of discharges of the liquid from the at least one recording element group; and determining a performance of the maintenance of the two recording element substrates based on the number counted in the counting step, wherein in the determining step, (i) if the number counted for one recording element substrate of the two recording element substrates is equal to or more than a first threshold value and the number counted for another recording element substrate of the two recording element substrates is equal to or more than the first threshold value, the performance of the maintenance of the one and another recording element substrates is determined, (ii) if the number counted for the one recording element substrate is equal to or more than the first threshold value and the number counted for the another recording element substrate is less than the first threshold value and is equal to or more than a second threshold value smaller than the first threshold value, the performance of the maintenance of the one and another recording element substrates is determined, and (iii) if the number counted for the one recording element substrate is equal to or more than the first threshold value and the number counted for the another recording element substrate is less than the second threshold value, the performance of the maintenance of the one recording element substrate except for the another recording element substrate is determined.