# US 11,077,687 B2 · Inkjet printing apparatus and inkjet printing method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,077,687 B2 - Document ID: US11077687B2 - Status: Granted - Kind: B2 - Application number: 16/823,875 - Filed: 2020-03-19 - Published: 2020-10-01 - Granted: 2021-08-03 - Earliest claimed: 2019-03-27 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Shingo Nishioka; Sae Mogi; Satoshi Azuma; Kazuhiko Sato; Shin Genta; Mitsutoshi Nagamura; Masataka Kato; Yoshinori Nakajima; Kazuo Suzuki - Web page: https://patentgrep.com/patent/US11077687B2 ## CPC - B41J 2/16585: {for paper-width or non-reciprocating print heads} - B41J 25/006: {for oscillating, e.g. page-width print heads provided with counter-balancing means or shock absorbers} - B41J 2/16538: {with brushes or wiper blades perpendicular to the nozzle plate} - B41J 2/2132: {Print quality control characterised by dot disposition, e.g. for reducing white stripes or banding (methods for local corrections by dot omission, image edge enhancement, or multi-pass mask selection G06K15/102; colour conversion H04N1/40)} - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS ## Abstract Images with high image quality having less time-difference unevenness are outputted in an inkjet printing apparatus that performs multi-pass printing using full-line inkjet print heads 2. For this purpose, a CPU is capable of setting a first printing method in which an image for a unit area is printed by a specified number of printing conveyance operations and a second printing method in which an image for a unit area is printed by a smaller number than the specified number of printing conveyance operations. The CPU sets conveyance conditions such that a taken time for one printing conveyance operation of the printing conveyance operations for a unit area in the second printing method is smaller than a taken time for one successive printing conveyance operation of the printing conveyance operations for a unit area in the first printing method. ## Claims ### Claim 1 An inkjet printing apparatus comprising: a print head that has multiple nozzles configured to eject ink and arrayed in a first direction; a conveying unit capable of conveying a print medium relative to the print head in a second direction intersecting the first direction and in a third direction opposite to the second direction; and a control unit configured to control the print head and the conveying unit such that an image for a unit area is printed by multiple printing conveyance operations in which a printing conveyance operation for conveying the print medium in the second direction while ejecting ink to the unit area of the print medium and a printing conveyance operation for conveying the print medium in the third direction while ejecting ink to the unit area of the print medium are repeated alternately, wherein the control unit is capable of setting a first printing method in which an image for a unit area is printed by a specified number of the printing conveyance operations and a second printing method in which an image for a unit area is printed by a smaller number than the specified number of the printing conveyance operations, and the control unit sets the first printing method and the second printing method such that a time to be taken for one printing conveyance operation of the printing conveyance operations for a unit area in the second printing method is smaller than a time to be taken for one printing conveyance operation of the printing conveyance operations for a unit area in the first printing method. ### Claim 2 (depends on 1) The inkjet printing apparatus according to claim 1, wherein the control unit makes the time to be taken for one printing conveyance operation in the second printing method shorter than the time to be taken for one printing conveyance operation in the first printing method by making a width of a unit area in a direction of the conveyance in the second printing method smaller than the width in the first printing method. ### Claim 3 (depends on 2) The inkjet printing apparatus according to claim 2, wherein the control unit sets the width differently depending on the type of print medium. ### Claim 4 (depends on 3) The inkjet printing apparatus according to claim 3, wherein the control unit sets the second printing method such that the width for a first print medium that is relatively glossy is smaller than the width for a second print medium that is relatively less glossy. ### Claim 5 (depends on 3) The inkjet printing apparatus according to claim 3, wherein the control unit sets the second printing method such that the width for a print medium with a coating layer having at least one of a function for receiving ink and a function for reacting with ink is smaller than the width for a print medium without the coating layer. ### Claim 6 (depends on 1) The inkjet printing apparatus according to claim 1, wherein the control unit makes the time to be taken for one printing conveyance operation in the second printing method shorter than the time to be taken for one printing conveyance operation in the first printing method by making conveyance speed of the printing conveyance operation in the second printing method higher than the conveyance speed in the first printing method. ### Claim 7 (depends on 6) The inkjet printing apparatus according to claim 6, wherein the control unit sets the conveyance speed differently depending on the type of print medium. ### Claim 8 (depends on 7) The inkjet printing apparatus according to claim 7, wherein the control unit sets the second printing method such that the conveyance speed of a first print medium that is relatively glossy is higher than the conveyance speed of a second print medium that is relatively less glossy. ### Claim 9 (depends on 7) The inkjet printing apparatus according to claim 7, wherein the control unit sets the second printing method such that the conveyance speed of a print medium with a coating layer having at least one of a function for receiving ink and a function for reacting with ink is higher than the conveyance speed of a print medium without the coating layer. ### Claim 10 (depends on 1) The inkjet printing apparatus according to claim 1, wherein the print head has nozzle rows each composed of multiple nozzles configured to eject ink and arrayed in the first direction, and each of the nozzle rows is associated with a different color. ### Claim 11 (depends on 1) The inkjet printing apparatus according to claim 1, wherein the print medium is a long length of a print medium held in the form of a roll. ### Claim 12 An inkjet printing method for an inkjet printing apparatus including: a print head that has multiple nozzles configured to eject ink and arrayed in a first direction; and a conveying unit capable of conveying a print medium relative to the print head in a second direction intersecting the first direction and in a third direction opposite to the second direction, wherein an image for a unit area is printed by multiple printing conveyance operations in which a printing conveyance operation for conveying the print medium in the second direction while ejecting ink to the unit area of the print medium and a printing conveyance operation for conveying the print medium in the third direction while ejecting ink to the unit area of the print medium are repeated alternately, a first printing method and a second printing method are settable; in the first printing method, an image for a unit area is printed by a specified number of the printing conveyance operations; and in the second printing method, an image for a unit area is printed by a smaller number than the specified number of the printing conveyance operations, and the first printing method and the second printing method are set such that a taken time for one printing conveyance operation of the printing conveyance operations for a unit area in the second printing method is smaller than a taken time for one printing conveyance operation of the printing conveyance operations for a unit area in the first printing method.