Patent ID: 9186886
Filing Date: 2015-11-17
Classification: B41J

Abstract:
1. An ejection adjustment pattern forming method of forming an ejection adjustment pattern on a print medium with an inkjet head, which has a plurality of nozzles from which ink is ejected, with reciprocally moving the inkjet head in a predetermined scanning direction, the method comprising: a thickness pattern forming step of forming a first thickness measurement pattern with the plurality of nozzles when the inkjet head is moving in one direction and a second thickness measurement pattern with the plurality of nozzles when the inkjet head is moving the other direction, a judging pattern forming step of forming, in each of the plurality of pattern forming areas, a judging pattern, the judging pattern including a line-like first judging pattern which is formed with the same ones of the plurality of nozzles used to form the thickness measurement pattern when the inkjet head is moved in the one direction, and a line-like second judging pattern which is formed with the same ones of the plurality of nozzles used to form the thickness measurement pattern when the inkjet head is moved in the other direction, the judging pattern being used to judge how close a positional relationship between the first measurement pattern and the second measurement pattern in the predetermined scanning direction; and a dummy pattern forming step of forming, in each of the plurality of pattern forming areas, a dummy pattern at a position adjacent, in the predetermined scanning direction, to the first and second thickness measurement patterns; wherein, in each of the pattern forming areas, the ejection condition for the plurality of nozzles when the first thickness measurement pattern and the ejection condition for the plurality of nozzles when the first judging pattern is formed when the inkjet head is moved in the one direction are the same, and the ejection condition for the plurality of nozzles when the second thickness measurement pattern and the ejection condition for the plurality of nozzles when the second judging pattern is formed when the inkjet head is moved in the other direction are the same, and wherein the ejection condition of the plurality of nozzles are differentiated for the plurality of pattern forming areas so that the positional relationship between the first judging pattern and the second judging pattern in the predetermined scanning position are different among the plurality of pattern forming areas.