Printing apparatus and print control method

A printing apparatus that performs printing by ejecting ink onto a print medium having a shape elongated in a conveyance direction, the printing apparatus comprising:

• a conveyance mechanism configured to convey the print medium in a first direction;
• at least one ink ejection head including a plurality of nozzles arranged in a second direction orthogonal to the first direction, and configured to eject ink from the plurality of nozzles onto the print medium being conveyed by the conveyance mechanism;
• at least one end detection sensor configured to detect a position of an end of the print medium being conveyed by the conveyance mechanism;
• a mark image detection sensor configured to detect a mark image to be placed at a predetermined position on the print medium;
• a processor;
• and
• a memory configured to store a program, wherein
• when the program stored in the memory is executed by the processor, the program causes the processor to execute:
• (A) obtaining a meandering amount of the print medium on a basis of the position of the end detected by the at least one end detection sensor,
• (B) generating printing image data by determining, on a basis of input image data including a plurality of images, print positions of respective images on each of a plurality of pages to be printed, in consideration of the meandering amount, and
• (C) controlling ejection of ink from the at least one ink ejection head on a basis of the printing image data,
• the plurality of pages includes a nozzle check page including the mark image and an ejection failure detecting pattern image for detecting a nozzle in an ejection failure state from among the plurality of nozzles, and a normal page including the mark image and an image other than the ejection failure detecting pattern image, and
• in generating the printing image data, for the normal page, the processor shifts print positions of all the images in the second direction on a basis of the meandering amount with reference to the print positions when the meandering amount is zero, and for the nozzle check page, the processor shifts a print position of the mark image in the second direction on a basis of the meandering amount with reference to the print position when the meandering amount is zero while maintaining a print position of the ejection failure detecting pattern image at the print position when the meandering amount is zero.

A print control method used in a printing apparatus that performs printing by ejecting ink onto a print medium having a shape elongated in a conveyance direction, the printing apparatus including

• a conveyance mechanism configured to convey the print medium in a first direction,
• at least one ink ejection head including a plurality of nozzles arranged in a second direction orthogonal to the first direction, and configured to eject ink from the plurality of nozzles onto the print medium being conveyed by the conveyance mechanism,
• at least one end detection sensor configured to detect a position of an end of the print medium being conveyed by the conveyance mechanism, and
• a mark image detection sensor configured to detect a mark image to be placed at a predetermined position on the print medium,
• the print control method comprising:
• obtaining a meandering amount of the print medium on a basis of the position of the end detected by the at least one end detection sensor;
• generating printing image data by determining, on a basis of input image data including a plurality of images, print positions of respective images on each of a plurality of pages to be printed, in consideration of the meandering amount;
• and
• controlling ejection of ink from the at least one ink ejection head on a basis of the printing image data, wherein
• the plurality of pages includes a nozzle check page including the mark image and an ejection failure detecting pattern image for detecting a nozzle in an ejection failure state from among the plurality of nozzles, and a normal page including the mark image and an image other than the ejection failure detecting pattern image, and
• in generating the printing image data, for the normal page, print positions of all the images are shifted in the second direction on a basis of the meandering amount with reference to the print positions when the meandering amount is zero, and for the nozzle check page, a print position of the ejection failure detecting pattern image is maintained at the print position when the meandering amount is zero and a print position of the mark image is shifted in the second direction on a basis of the meandering amount with reference to the print position when the meandering amount is zero.