Inkjet printing apparatus and inkjet printing method

Patent metadata

Field	Value
Publication number	US-8931869-B2
Application number	US-201213584311-A
Country	US
Kind code	B2
Filing date	Aug 13, 2012
Priority date	Aug 18, 2011
Publication date	Jan 13, 2015
Grant date	Jan 13, 2015

Abstract

In a serial type of color inkjet printing apparatus having a plurality of nozzle arrays, overlapping areas are provided in the respective operating nozzle areas, but printing of a high-quality image can be achieved without color banding and gloss variations accompanying non-uniformity in the ink application process. To attain this, while the operating nozzle areas of the plurality of nozzle arrays partially overlap with each other, the overlapping area of the operating nozzle area of each nozzle array is set to be equal to an integral multiple of the amount of conveyance. In consequence, the ink application process for the entire image area is made uniform.

First claim

What is claimed is:

1. An inkjet printing apparatus, which prints an image on a print medium by performing, in alternate order, a printing scan in which a plurality of nozzle arrays each including a plurality of nozzles arranged in a predetermined direction are moved relative to the print medium, and a conveying operation of conveying the print medium in the predetermined direction, comprising:
a setting unit configured to set an operating nozzle area, operated for printing to a middle region of the print medium, for each of the plurality of nozzle arrays;
a unit configured to execute the printing scan by moving the plurality of nozzle arrays in a direction crossing the predetermined direction while ink is ejected from the operating nozzle areas set by the setting unit; and
a unit configured to execute the conveying operation of conveying the print medium in the predetermined direction by an amount of conveyance determined depending on a set print mode,
wherein the setting unit sets the operating nozzle area for each of the plurality of nozzle arrays such that an overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays is an integral multiple of the amount of conveyance.

2. The inkjet printing apparatus according to claim 1 , further comprising: a correction unit configured to acquire, for each of the plurality of nozzle arrays, a correction value used for adjusting a print position on the print medium in the predetermined direction,
wherein the setting unit sets the operating nozzle area for each of the plurality of nozzle arrays in accordance with the set print mode and the correction value acquired by the correction unit such that the overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays is an integral multiple of the amount of conveyance.

3. The inkjet printing apparatus according to claim 1 , wherein the plurality of nozzle arrays include nozzle arrays from which cyan, magenta, yellow and black inks are ejected.

4. An inkjet printing method for printing an image on a print medium by performing, in alternate order, a printing scan in which a plurality of nozzle arrays each including a plurality of nozzles arranged in a predetermined direction are moved relative to a print medium, and a conveying operation of conveying the print medium in the predetermined direction, comprising:
a setting step of setting an operating nozzle area, operated for printing to a middle region of the print medium, for each of the plurality of nozzle arrays;
a step of executing the printing scan by moving the plurality of nozzle arrays in a direction crossing the predetermined direction while ink is ejected from the operating nozzle areas set in the setting step; and
a step of executing the conveying operation by conveying the print medium in the predetermined direction by an amount of conveyance determined depending on a set print mode,
wherein the operating nozzle area for each of the plurality of nozzle arrays is set, in the setting step, sauch that an overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays is an integral multiple of the amount of conveyance.

5. The inkjet printing method according to claim 4 , further comprising:
a correction step of acquiring, for each of the plurality of nozzle arrays, a correction value used for adjusting a print position on the print medium in the predetermined direction,
wherein the operating nozzle area for each of the plurality of nozzle arrays is set, in the setting step, in accordance with the set print mode and the correction value acquired in the correction step such that the overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays is the integral multiple of the amount of conveyance.

6. The inkjet printing method according to claim 4 , wherein the plurality of nozzle arrays include nozzle arrays from which cyan, magenta, yellow and black inks are ejected.

7. An inkjet printing apparatus comprising:
a print unit configured to execute a printing scan by moving a plurality of nozzle arrays, each including a plurality of nozzles arranged in a predetermined direction, in a direction crossing the predetermined direction relative to a print medium while ejecting ink;
a conveyance unit configured to execute a conveying operation of conveying the print medium in the predetermined direction by a conveyance amount determined depending on a determined print mode, wherein the printing scan by the print unit and the conveying operation of the conveying unit are executed in alternate order; and
a setting unit configured to set an operating nozzle area, operated for printing to a middle region of the print medium, for each of the plurality of nozzle arrays in accordance with the determined print mode, such that (i) each of the operating nozzle areas is a part of the corresponding nozzle array, (ii) the operating nozzle areas are shifted in the predetermined direction with respect to each other, and (iii) a length of an overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays corresponds to an integral multiple of the conveyance amount of the conveyance operation by the conveyance unit,
wherein the print unit prints an image on the print medium using the operating nozzle areas set by the setting unit.

8. The inkjet printing apparatus according to claim 7 , further comprising:
a correction unit configured to acquire, for each of the plurality of nozzle arrays, a correction value used for adjusting a print position on the print medium in the predetermined direction,
wherein the setting unit sets the operating nozzle area for each of the plurality of nozzle arrays in accordance with the determined print mode and the correction value acquired by the correction unit such that the length of the overlapping area in the predetermined direction of the operating nozzle areas of the plurality of nozzle arrays corresponds the integral multiple of the conveyance amount.

9. The inkjet printing apparatus according to claim 7 , further comprising:
a mode determining unit configured to determine a print mode by selecting one from a plurality print modes of which conveyance amounts of the conveyance operation by the conveyance unit are different from each other.

10. The inkjet printing apparatus according to claim 7 , wherein a shifted amount of the operating nozzle areas of the plurality of nozzle arrays corresponds to an integral multiple of the conveyance amount of the conveyance operation by the conveyance unit.

11. The inkjet printing apparatus according to claim 9 , wherein
in a case that the mode determining unit determines a first print mode, the setting unit sets the operating nozzle area for each of the plurality of nozzle arrays such that (i) each of the operating nozzle areas is a part of the corresponding nozzle array, (ii) the operating nozzle areas are shifted in the predetermined direction with respect to each other, and (iii) the length of the overlapping area, in the predetermined direction, of the operating nozzle areas of the plurality of nozzle arrays corresponds to the integral multiple of the conveyance amount of the conveyance operation by the conveyance unit, and
in a case that the mode determining unit determines a second print mode, the setting unit sets the operating nozzle area to an entire range of the nozzle array for each of the plurality of nozzle arrays.

12. The inkjet printing apparatus according to claim 9 , wherein in a case that the mode determining

Assignees

• Kawafuji Hiroshi
• Canon Kk

Inventors

• Kawafuji Hiroshi

Classifications

• B41J2/2132

  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) · CPC title

• B41J19/147

  Colour shift prevention · CPC title

• B41J29/38 Primary

  Drives, motors, controls or automatic cut-off devices for the entire printing mechanism · CPC title