JP2009285888A - Color management method and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a printer which can achieve a highly-accurate printing without enlarging the curing part. <P>SOLUTION: The delivery mechanism of the printer includes a plurality of inkjet head units 31 and a lamp head unit for irradiating ultraviolet rays towards a linear irradiation domain extending in the direction perpendicular to the printing direction. Each inkjet head unit 31 includes the first head 32a to the sixth head 32f which are arranged alternately, and the adjoining heads are arranged in the position shifted in the printing direction. In the printer, the difference of the printing result based on the difference of the curing delay time of inks of a plurality of heads is corrected by correcting the ink discharge out of each head from color space correction information related to each head without installing a plurality of ultraviolet-ray lamps corresponding to each of the a plurality of heads. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a color management method in an inkjet printing apparatus and a printing apparatus to which the color management method is applied.

  2. Description of the Related Art Conventionally, an ink jet printing apparatus that performs printing on a print medium by scanning a discharge mechanism in which a plurality of discharge ports for discharging minute ink droplets are arranged relative to the print medium has been used. ing.

In the inkjet printer of Patent Document 1, a plurality of recording heads that discharge ultraviolet curable ink are arranged in a staggered pattern in the sub-scanning direction, and a plurality of recording heads are provided on both sides of the plurality of recording heads in the main scanning direction. A plurality of ultraviolet light sources corresponding to the above are arranged in a staggered pattern in the sub-scanning direction. For a plurality of recording heads, by equalizing the distance in the main scanning direction between the recording head and the ultraviolet light source corresponding to the recording head, the time from ink ejection to curing (hereinafter referred to as “curing delay time”). Are equalized). This prevents the shape of the micro droplets (so-called dots) of ink ejected from a plurality of recording heads from being different due to the difference in curing delay time, thereby improving printing accuracy. Is realized.
JP 2005-103844 A

  By the way, in the inkjet printer of patent document 1, it is necessary to provide the ultraviolet light source corresponding to each of a some recording head, and the number of ultraviolet light sources will increase. In recent years, with the increase in the definition of an image printed by a printing apparatus, a structure in which a large number of inkjet heads with different positions in the main scanning direction are provided in one recording head has been adopted. When the structure of Patent Document 1 is applied to an ink jet printer having a head, a large number of ultraviolet light sources having different positions in the main scanning direction are provided for one recording head, and the ultraviolet light source of the ink jet printer is enlarged. The discharge mechanism having the ultraviolet light source and the recording head is increased in size. In a printing apparatus (so-called one-pass printing apparatus) that performs printing by a single scan of the ejection mechanism with respect to the print medium, if the size of the ejection mechanism in the scanning direction is large, meandering and feed unevenness when the substrate moves in the scanning direction The displacement of the relative position of the ejection mechanism with respect to the base material due to the above-mentioned causes increases, and the print quality may be deteriorated.

  The present invention has been made in view of the above problems, and realizes high-precision printing without increasing the size of the cured portion by correcting the difference in the printing result due to the difference in the curing delay time of the ink for each head. The purpose is that.

  The invention according to claim 1 is a color management method in an ink jet type printing apparatus, wherein the printing apparatus prints from a plurality of first ejection openings arranged in a predetermined arrangement direction intersecting the printing direction. A first head that ejects ink toward the medium and prints in a first region on the print medium in a single pass; and adjacent to the first head in the arrangement direction and the first head in the printing direction. The first region on the print medium is ejected from a plurality of second ejection ports arranged at positions shifted from one head and arranged in the arrangement direction toward the print medium in one pass. A second head that performs printing in a second region adjacent to the first head, a scanning mechanism that moves the print medium relative to the first head and the second head in the printing direction, the first head, and the Second And a color space correction information, and a curing unit that cures the ink by passing through the ink applied on the print medium from the first head and the second head. A storage unit; and a drawing control unit configured to correct ejection of ink from the first head and the second head based on the color space correction information, and the color management method includes: a) based on test image data Moving the print medium in the printing direction relative to the first head and the second head while ejecting ink from the first head and the second head toward the print medium, A step of curing the ink applied on the printing medium by the curing unit; and b) a printing result in the first area on the printing medium and a partial image corresponding to the first area of the test image. A step of acquiring first color space correction information for the first area, and c) a printing result in the second area on the print medium and a partial image corresponding to the second area of the test image. And obtaining second color space correction information for the second region in comparison.

  A second aspect of the present invention is the color management method according to the first aspect, wherein the printing apparatus has a structure similar to that of the first head and has a distance in the printing direction from the curing unit. Is equal to the distance in the printing direction between the first head and the hardened portion, and is adjacent to the opposite side of the second head from the first head, on the print medium in one pass. A third head that performs printing in a third area adjacent to the second area, and the first color space correction information is used for correcting ejection of ink from the first head and the third head. The

  A third aspect of the present invention is the color management method according to the first or second aspect, wherein the scanning mechanism moves the print medium to a plurality of positions relative to the first head and the second head. The first color space correction associated with each of the plurality of movement speeds by allowing the movement at a movement speed and performing the steps a) to c) with respect to each of the plurality of movement speeds. Information and the second color space correction information are acquired.

  A fourth aspect of the present invention is the color management method according to any one of the first to third aspects, wherein the ink is an ultraviolet curable ink, and the cured portion is in the printing direction on the print medium. The irradiation region extending in the direction perpendicular to is irradiated with ultraviolet rays.

  The invention according to claim 5 is an ink jet printing apparatus that discharges ink from a plurality of first discharge ports arranged in a predetermined arrangement direction intersecting a printing direction toward a printing medium, A first head that prints in a first region on the print medium in a single pass, and is disposed adjacent to the first head in the arrangement direction and at a position shifted from the first head in the printing direction. , Ink is ejected from the plurality of second ejection openings arranged in the arrangement direction toward the print medium, and printing is performed in a second area adjacent to the first area on the print medium in one pass. A second head to perform, a scanning mechanism for moving the print medium in the printing direction relative to the first head and the second head, and a position fixed to the first head and the second head And said A curing unit that cures the ink by passing over the ink applied on the print medium from one head and the second head, first color space correction information for the first region, and second for the second region A storage unit that stores color space correction information; and ink discharge from the first head is corrected based on the first color space correction information, and ink discharge from the second head is corrected to the second color space correction. A drawing control unit that performs correction based on the information.

  A sixth aspect of the present invention is the printing apparatus according to the fifth aspect, wherein the scanning mechanism moves the print medium at a plurality of moving speeds relative to the first head and the second head. The storage unit stores the first color space correction information and the second color space correction information associated with each of the plurality of moving speeds.

  A seventh aspect of the present invention is the printing apparatus according to the fifth or sixth aspect, wherein the ink is an ultraviolet curable ink, and the cured portion is a direction perpendicular to the printing direction on the print medium. Irradiate ultraviolet rays to the irradiation region extending to

  In the present invention, by correcting the difference in the printing result due to the difference in the curing delay time of the ink for each head, high-precision printing can be realized without increasing the size of the curing portion. According to the third and sixth aspects of the invention, it is possible to perform an appropriate color space correction according to the speed.

  FIG. 1 is a perspective view showing an appearance of a printing apparatus 1 according to an embodiment of the present invention. The printing apparatus 1 is an apparatus that performs color printing by an inkjet method on a substrate 9 that is a sheet-like printing medium having liquid repellency such as a film.

  The printing apparatus 1 shown in FIG. 1 is in the process of being moved by a conveyance unit 27 that is a scanning mechanism that moves the sheet-like base material 9 in the Y direction (hereinafter also referred to as “printing direction”) in FIG. A discharge mechanism 3 for discharging fine droplets of ink toward the substrate 9, and a control unit 4 for controlling the configuration thereof. In the transport unit 27, the base material 9 is movable at a plurality of moving speeds. In this Embodiment, the moving speed of the base material 9 shall be either 100 mm / second, 250 mm / second, 400 mm / second, or 500 mm / second.

  In the transport unit 27, a plurality of rollers 271 that are each long in the X direction in FIG. 1 are arranged in the Y direction, and a roll-shaped substrate 9 (supply roll) is placed on the (+ Y) side of the plurality of rollers 271. A supply unit 272 for holding is provided, and a winding unit 273 for holding the roll-shaped base material 9 (winding roll) is provided on the (−Y) side of the plurality of rollers 271. Actually, the base material 9 is rolled in each of the supply unit 272 and the winding unit 273. In the following description, the term “base material 9” simply means the base material 9 that is being conveyed (that is, the base material 9 on the plurality of rollers 271).

  One roller 271 a of the transport unit 27 is provided with an encoder 29 that detects the moving speed of the base material 9 in the printing direction, and a later-described movement control unit 42 (see FIG. 4) is based on the output of the encoder 29. By controlling the rotation of the motor 273, the base material 9 moves at a constant speed in the (-Y) direction. At this time, by applying a load (tension) in the direction opposite to the movement direction (that is, (+ Y) direction) to the base material 9 by the motor of the supply unit 272, the base material on the plurality of rollers 271 is provided. 9 moves smoothly without undulations. Note that the encoder 29 that detects the moving speed of the base material 9 can be regarded as detecting a change in the position in the printing direction of one part on the base material 9 during conveyance.

  The ejection mechanism 3 is disposed above the plurality of rollers 271, and the ejection mechanism 3 is fixed to the frame 25 provided on the base 20 so as to straddle the plurality of rollers 271. A light source 39 for emitting ultraviolet rays is provided on the frame 25, and a plurality of optical fibers (actually, the plurality of optical fibers are bundled. In FIG. The light from the light source 39 is introduced into the inside of the discharge mechanism 3.

  FIG. 2 is a bottom view showing the discharge mechanism 3. As shown in FIG. 2, the ejection mechanism 3 includes a plurality of (four in the present embodiment) ink jet head units 31 that eject inks of different colors, and these ink jet head units 31. Have a similar structure. The plurality of inkjet head units 31 are arranged in the Y direction (that is, the printing direction) and attached to the head unit attachment portion 30 of the ejection mechanism 3. The most (+ Y) side inkjet head unit 31 in FIG. 2 ejects K (black) color ink, and the (−Y) side inkjet head unit 31 of the K inkjet head unit 31 is C (cyan). The color ink is ejected, the (−Y) side ink jet head unit 31 of the C ink jet head unit 31 ejects M (magenta) color ink, and the most (−Y) side ink jet head unit 31 is Y. (Yellow) color ink is ejected. Each color ink is an ultraviolet curable ink containing an ultraviolet curing agent.

  In the ejection mechanism 3, the lamp head unit 38, which is a head unit connected to the light source 39 (see FIG. 1), together with these inkjet head units 31 on the (−Y) side of the four inkjet head units 31. They are arranged in the Y direction (that is, the printing direction) and attached to the head unit attachment portion 30. In other words, the position of the lamp head unit 38 is fixed with respect to the four inkjet head units 31. Here, when a plurality of head units attached to the head unit attachment portion 30 are collectively referred to as a head unit group, the head unit group includes the above-described inkjet head units 31 of K, C, M, and Y, and In addition to the lamp head unit 38, for example, an inkjet head unit for other colors such as light cyan, light magenta, and white may be included.

  In the lamp head unit 38, a plurality of optical fibers are arranged along the X direction, and the lamp head unit 38 causes linear irradiation extending in the X direction (that is, a direction perpendicular to the printing direction) on the substrate 9. The region is irradiated with ultraviolet light. In the printing apparatus 1, the ultraviolet curable ink applied from the plurality of inkjet head units 31 onto the substrate 9 is irradiated with ultraviolet rays from the lamp head unit 38 passing over the ink, whereby the substrate On 9 the ink is cured. That is, the lamp head unit 38 is an ultraviolet irradiation unit that irradiates the ink ejected onto the substrate 9 with ultraviolet rays, and is also a curing unit that cures the ink.

  In the printing apparatus 1, the inkjet head unit 31 and the lamp head unit 38 extend over the entire printing area on the base material 9 (here, the entire X direction of the base material 9 in the X direction perpendicular to the printing direction). The printing of the image on the substrate 9 is completed only once the substrate 9 passes under the discharge mechanism 3 once (so-called one-pass printing is performed).

  FIG. 3 is a bottom view showing one inkjet head unit 31. As shown in FIG. 3, the inkjet head unit 31 includes a plurality (six in this embodiment) of inkjet heads 32a to 32f, and these inkjet heads have the same structure. The inkjet head unit 31 includes a center rib 311 that is an attachment member to which the plurality of inkjet heads 32a to 32f are attached. The center rib 311 has a T-shaped outer shape when viewed along the X direction, a plate-shaped rib upper portion 3111 having a main surface substantially perpendicular to the Z direction, and a main rib substantially perpendicular to the Y direction. A plate-like rib lower portion 3112 having a surface is provided.

  The plurality of inkjet heads 32a to 32f are arranged in the X direction so as to be alternately positioned on the (−Y) side and the (+ Y) side of the rib lower part 3112 of the center rib 311 (the so-called zigzag arrangement). ), Each inkjet head is disposed at a position shifted in the Y direction (that is, the printing direction) from the adjacent inkjet head in the X direction, and at least a part of the adjacent inkjet head overlaps in the printing direction. In the following description, the six inkjet heads 32a to 32f are referred to as a first head 32a to a sixth head 32f in order from the (−X) side to the (+ X) side.

  The distances in the Y direction (that is, the printing direction) between each of the first head 32a, the third head 32c, and the fifth head 32e and the lamp head unit 38 (see FIG. 2) are equal. Further, the distances in the Y direction between the second head 32b, the fourth head 32d, and the sixth head 32f and the lamp head unit 38 are equal, and the first head 32a, the third head 32c, and the fifth head 32e, respectively. And the distance in the Y direction between the lamp head unit 38 and the lamp head unit 38 is larger.

  In the inkjet head unit 31, the second head 32b is disposed adjacent to the first head 32a and the third head 32c in the X direction and at a position shifted from the first head 32a and the third head 32c in the Y direction. The (−X) side end of the second head 32b overlaps the (+ X) side end of the first head 32a in the Y direction, and the (+ X) side end of the second head 32b is The second head 32b overlaps the (−X) side end of the third head 32c adjacent to the opposite side of the first head 32a in the Y direction. The arrangement of the fourth head 32d with respect to the third head 32c and the fifth head 32e is the same as the arrangement of the second head 32b with respect to the first head 32a and the third head 32c, and the sixth head 32f has the fifth head 32e. The arrangement of the second head 32b is the same as the arrangement of the second head 32b with respect to the first head 32a.

  The first head 32a has a plurality of first discharge ports 331a arranged in a predetermined arrangement direction that intersects the printing direction and approximately parallel to the X direction in FIG. 3 on the lower surface (that is, the (−Z) side surface). And a small droplet of ink is ejected from the plurality of first ejection ports 331 a toward the substrate 9. Similarly to the first head 32a, the second head 32b also has a plurality of second ejection ports 331b arranged in the arrangement direction, and microdroplets of ink are supplied from the plurality of second ejection ports 331b to the substrate 9. Discharge toward Similarly, the third head 32c to the sixth head 32f have a plurality of third discharge ports 331c to 331f arranged in the arrangement direction. In FIG. 3, for convenience of illustration, the size of each discharge port and the distance in the arrangement direction between adjacent discharge ports are drawn larger than the actual size. The actual inkjet head unit 31 is provided with a larger number of ejection openings than shown in FIG.

  Each of the inkjet heads of the first head 32a to the sixth head 32f is provided with a plurality of ejection channels that guide ink toward the plurality of ejection ports, and a piezoelectric element (piezo element) is provided in the vicinity of the ejection port of each ejection channel. ) Is provided. When a discharge signal is applied to the drive unit, the drive unit is deformed, and the volume of the discharge channel near the discharge port (more specifically, the volume of the chamber provided near the discharge port of the discharge channel) decreases. To do. As a result, pressure is applied to the ink in the vicinity of the ejection port (that is, the ink in the chamber of the ejection flow path that guides the ink to the ejection port), and micro droplets of ink are ejected from the ejection port. Then, when the shape of the drive unit is restored, the volume of the ejection channel returns to the original in the vicinity of the ejection port, and an amount of ink equal to the minute droplets of the ejected ink is supplied to the ejection channel.

  FIG. 4 is a block diagram illustrating functions of the control unit 4 shown in FIG. 1, and FIG. 4 also shows the configuration of the printing apparatus 1 connected to the control unit 4. The control unit 4 includes a drawing control unit 41 that performs control related to ink ejection from each inkjet head of the four inkjet head units 31 (see FIG. 2), a movement control unit 42 that performs movement control with respect to the transport unit 27, and A storage unit 43 that stores information related to control by the drawing control unit 41 and the movement control unit 42 is provided. In FIG. 4, only one inkjet head unit 31 is shown for convenience of illustration. In the storage unit 43, color space correction information corresponding to each of the first head 32a to the sixth head 32f of each inkjet head unit 31 is stored in advance. In the following description, the color space correction information corresponding to each of the first head 32a to the sixth head 32f is referred to as first color space correction information to sixth color space correction information.

  When printing is performed by the printing apparatus 1 shown in FIG. 1, the transport unit 27 is controlled by the movement control unit 42 (see FIG. 4) of the control unit 4, so that the base material 9 is in the printing direction (that is, FIG. 1 in the Y direction, and in a direction substantially perpendicular to the arrangement direction of the plurality of ejection ports of each inkjet head. Further, in parallel with the movement of the base material 9, the drawing control unit 41 (see FIG. 4), based on the data of the image to be printed on the base material 9, each ink jet head of each ink jet head unit 31 (that is, By controlling a plurality of driving units of the first head 32a to the sixth head 32f), every time the base material 9 moves by a predetermined distance in the printing direction, minute droplets of ink are ejected from the ejection port and the base 9 is moved. It is applied on the material 9.

  FIG. 5 is an enlarged plan view showing a part of the base material 9. In the printing apparatus 1, six strip-shaped regions 91 a to 91 f (in the following description, from the (−X) side to the (+ X) side) arranged in the X direction (that is, the direction perpendicular to the printing direction) on the substrate 9. The first head 32a to the sixth head 32f of each ink jet head unit 31 pass through the first area 91a to the sixth area 91f in order toward the first area. Printing is performed in the area 91a to the sixth area 91f. In FIG. 5, the boundary between the first region 91a to the sixth region 91f is indicated by a broken line.

  The ink applied from the first head 32a to the sixth head 32f of each inkjet head unit 31 to the first region 91a to the sixth region 91f of the base material 9 is irradiated with ultraviolet rays from the lamp head unit 38 passing over the ink. Is cured by irradiation. In the ejection mechanism 3, the position of the lamp head unit 38 is fixed with respect to the first head 32 a to the sixth head 32 f of each inkjet head unit 31, and as described above, the second head 32 b and the lamp head unit 38. The distance in the printing direction between the first head 32a and the lamp head unit 38 is greater than the distance in the printing direction. In the present embodiment, each of the first head 32 a and the second head 32 b of the inkjet head unit 31 that is adjacent to the lamp head unit 38 and discharges Y (yellow) color ink and the lamp head unit 38. The distance is 80 mm and 100 mm.

  Accordingly, the time from when the ink is ejected from the second head 32b to the second region 91b of the substrate 9 until the ink is irradiated with the ultraviolet rays and cured (hereinafter referred to as “curing delay time”) is the first. Curing delay time of ink from the head 32a (that is, from when the ink is ejected from the first head 32a to the first region 91a adjacent to the second region 91b in the X direction until the ink is irradiated with ultraviolet rays and cured. Time). For example, when the moving speed of the substrate 9 is 500 mm / second, the curing delay time of the ink from the first head 32a and the curing delay time of the ink from the second head 32b are 0.16 seconds and 0. 2 seconds.

  Further, the curing delay time of the ink ejected from the third head 32c to the third region 91c adjacent to the second region 91b in the X direction, and the ejected from the fifth head 32e to the fifth region 91e. The curing delay time of the ink is equal to the curing delay time of the ink from the first head 32a, and the curing delay time of the ink ejected from the fourth head 32d and the sixth head 32f with respect to the fourth region 91d and the sixth region 91f. Is equal to the curing delay time of the ink from the second head 32b.

  In the printing apparatus 1, the ink ejection from the first head 32 a to the sixth head 32 f in each inkjet head unit 31 is performed by the drawing control unit 41 on the first color space correction information to the first color stored in the storage unit 43. From the first head 32a, the third head 32c, and the fifth head 32e, correction is performed based on the six color space correction information (that is, the color space correction information for each of the first area 91a to the sixth area 91f). The first region 91a due to the difference between the curing delay time of the ink and the curing delay time of the ink from the second head 32b, the fourth head 32d, and the sixth head 32f (that is, the difference in the curing delay time of the ink for each head). The difference in the printing result in the sixth region 91f (for example, the difference in the shape of the ink droplets on the substrate 9 when cured) is corrected. .

  By the way, assuming a printing apparatus in which the difference in ink curing delay time is not corrected, in such a printing apparatus, the difference in printing result due to the difference in ink curing delay time in the six inkjet heads of the first head to the sixth head. To prevent this, six ultraviolet lamps respectively corresponding to the first to sixth heads are provided in a staggered manner in the lamp head unit so that the distances in the printing direction between the inkjet heads and the ultraviolet lamps are equal. There is a need. For this reason, a lamp head unit will enlarge.

  In contrast, in the printing apparatus 1 according to the present embodiment, the lamp head unit 38 does not include a plurality of ultraviolet lamps corresponding to the first head 32a to the sixth head 32f, and the first head 32a to the first head 32a. By correcting the ejection of ink from the six heads 32f, the difference in printing results due to the difference in the curing delay time of the inks of the first head 32a to the sixth head 32f is corrected. Therefore, high-precision printing on the substrate 9 is realized without increasing the size of the lamp head unit 38.

  In the present embodiment, as described above, the curing delay times of the inks from the first head 32a, the third head 32c, and the fifth head 32e are equal to each other. Therefore, the third color space correction information and the fifth color space correction information are used. Is substantially the same as the first color space correction information. Further, since the curing delay times of the inks from the second head 32b, the fourth head 32d, and the sixth head 32f are equal to each other, the fourth color space correction information and the sixth color space correction information are substantially the same as the second color space correction information. It will be the same. Therefore, in the printing apparatus 1, only the first color space correction information and the second color space correction information are stored in the storage unit 43 as the color space correction information, and the first head 32a, the third head 32c, and the fifth head 32e are stored. The first color space correction information is used for correcting the ink discharge from the second head, and the second color space correction information is used for correcting the ink discharge from the second head 32b, the fourth head 32d, and the sixth head 32f. Also good. Thereby, the capacity used for storing the color space correction information in the storage unit 43 can be reduced.

  As described above, in the transport unit 27, the base material 9 can move in the printing direction at a plurality of moving speeds (in this embodiment, 100 mm / second, 250 mm / second, 400 mm / second, or 500 mm / second). If the moving speed of the substrate 9 is changed, the curing delay time of ink from each inkjet head also changes. Therefore, in the printing apparatus 1, the first color space correction information to the sixth color space correction information (only the first color space correction information and the second color space correction information are associated with each of the plurality of moving speeds of the base material 9. Is used, the first color space correction information and the second color space correction information) are stored in the storage unit 43 in advance, and based on the color space correction information corresponding to the moving speed of the base material 9 by the transport unit 27. By controlling the ejection of ink from the first head 32a to the sixth head 32f, appropriate color space correction can be performed according to the moving speed of the substrate 9.

  Next, a method for acquiring color space correction information will be described. FIG. 6 is a diagram showing a flow of obtaining color space correction information. In the printing apparatus 1, first, ink is ejected from the first head 32 a to the sixth head 32 f (see FIG. 3) of each inkjet head unit 31 toward the base material 9 based on test image data prepared in advance. The base material 9 is moved in the printing direction at a single moving speed, and the ink applied on the base material 9 is cured by irradiation with ultraviolet rays from the lamp head unit 38 (step S11).

  Subsequently, the printing result in the first area 91a of the substrate 9 is compared with the partial image corresponding to the first area 91a (see FIG. 5) of the test image, and the first color space correction information for the first area 91a is acquired. (Step S12). In step S12, a plurality of first color space correction information respectively corresponding to the first heads 32a of the plurality of inkjet head units 31 is acquired, and associated with the moving speed of the substrate 9, the storage unit 43 (see FIG. 4).

  Further, the printing result in the second area 91b (see FIG. 5) and the partial image corresponding to the second area 91b of the test image are compared, and the second color space correction information for the second area 91b is acquired and the storage unit 43 is obtained. (Step S13). Also in step S13, similarly to step S12, a plurality of second color space correction information respectively corresponding to the second heads 32b of the plurality of inkjet head units 31 is acquired (the same applies to steps S14 to S17). Similarly, the print results in the third area 91c to the sixth area 91f (see FIG. 5) are compared with the partial images respectively corresponding to the third area 91c to the sixth area 91f of the test image, and the third area 91c to the third area 91f are compared. The third color space correction information to the sixth color space correction information for the six regions 91f are acquired and stored in the storage unit 43 (steps S14 to S17).

  When the first color space correction information to the sixth color space correction information are acquired, the presence / absence of the next movement speed is confirmed (step S18). If the next movement speed exists, the movement control unit 42 (FIG. 4), the moving speed of the base material 9 is changed (step S19). Then, returning to step S11, when the test image is printed, the first color space correction information to the sixth color space correction information are acquired, and the presence / absence of the next movement speed is confirmed, and the next movement speed exists. The moving speed of the base material 9 is changed (steps S11 to S19). In the printing apparatus 1, steps S <b> 11 to S <b> 19 are performed for each of the plurality of movement speeds of the base material 9, whereby the first color space correction information to the sixth color space correction information associated with each of the plurality of movement speeds. Is acquired.

  In the printing apparatus 1, among the plurality of combinations of the first color space correction information to the sixth color space correction information acquired by repeating steps S <b> 11 to S <b> 19, the first color space associated with the moving speed of the base material 9. By controlling the ejection of ink from the first head 32a to the sixth head 32f (see FIG. 3) of each inkjet head unit 31 based on the correction information to the sixth color space correction information, the first on the substrate 9 is controlled. Color management of the area 91a to the sixth area 91f (see FIG. 5) is performed. As a result, as described above, the difference in the printing result due to the difference in the curing delay time of the ink for each head is corrected, and high-precision printing is realized. Further, an appropriate color space correction is performed according to the moving speed of the base material 9.

  In the printing apparatus 1, the first color space correction information is used for correcting the ejection of ink from the first head 32a, the third head 32c, and the fifth head 32e, and the second head 32b, the fourth head 32d, and the sixth head. When the second color space correction information is used for correcting the ejection of ink from 32f, only the above steps S11 to S13 and steps S18 and S19 are performed for each of the plurality of moving speeds in the acquisition of the color space correction information. Thereby, acquisition of color space correction information is simplified.

  As mentioned above, although embodiment of this invention has been described, this invention is not limited to the said embodiment, A various change is possible.

  For example, the moving speed of the base material 9 may be freely set within a predetermined range. In this case, in the acquisition of the color space correction information, the color space correction information associated with each of the plurality of moving speeds within the predetermined range is acquired and stored in the storage unit 43. When the movement speed of the base material 9 at the time of printing is set to a speed other than the plurality of movement speeds, it is associated with each of two or more movement speeds from the color space correction information stored in the storage unit 43. Color space correction information is selected, and ejection from the inkjet head is corrected based on the color space correction information obtained by interpolating the two or more selected color space correction information. Appropriate color management corresponding to the moving speed is performed.

  Further, in the printing apparatus 1, printing may be performed using ink that is cured by means other than ultraviolet irradiation. For example, when ink that is cured by heating is used, instead of the lamp head unit 38, a heating unit such as a heater disposed facing the substrate 9 is provided on the ink applied to the substrate 9. The ejection mechanism 3 is provided as a curing portion that cures the ink passing through the nozzle.

  In the printing apparatus 1 shown in FIG. 1 (so-called roll-to-roll printing apparatus), the substrate 9 is moved in the printing direction intersecting the arrangement direction of the plurality of discharge ports by the transport unit 27 that moves the substrate 9 in the printing direction. Although it moves at a constant speed with respect to the ejection mechanism 3, the printing apparatus 1 may be provided with a mechanism for moving the ejection mechanism 3 in the printing direction. Further, as in the printing apparatus 1a shown in FIG. 7 (so-called sheet-fed printing apparatus), the stage 21 holding the rectangular base material 9 and the stage 21 in the printing direction (Y direction in FIG. 7). A moving stage moving mechanism 22 may be provided. In this way, the scanning mechanism that moves the base material 9 in the printing direction relative to the ejection mechanism 3 (that is, the first head 32a to the sixth head 32f of each inkjet head unit 31) is realized in various configurations. Is possible.

  The printing medium in the above-described printing apparatus may be a plate-like member or printing paper formed of plastic in addition to the sheet-like base material 9.

1 is a perspective view illustrating an appearance of a printing apparatus according to an embodiment. It is a bottom view of a discharge mechanism. It is a bottom view of an inkjet head unit. It is a block diagram which shows the function of a control unit. It is a top view which expands and shows a part of base material. It is a figure which shows the flow of acquisition of color space correction information. It is a perspective view which shows the other example of a printing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,1a Printing apparatus 9 Base material 27 Conveyance part 32a 1st head 32b 2nd head 32c 3rd head 38 Lamp head unit 41 Drawing control part 43 Memory | storage part 91a 1st area | region 91b 2nd area | region 91c 3rd area | region 331a 1st discharge | emission Outlet 331b second outlet S11-S19 step

Claims (7)

A color management method for an inkjet printer,
The printing device is
Ink is ejected from the plurality of first ejection openings arranged in a predetermined arrangement direction intersecting the printing direction toward the printing medium, and printing is performed on the first area on the printing medium in one pass. A first head;
Ink is directed toward the print medium from a plurality of second ejection ports arranged adjacent to the first head in the arrangement direction and shifted from the first head in the printing direction and arranged in the arrangement direction. A second head that ejects and prints in a second region adjacent to the first region on the print medium in a single pass;
A scanning mechanism that moves the print medium relative to the first head and the second head in the printing direction;
A curing unit that is fixed in position with respect to the first head and the second head, and that cures the ink by passing over the ink applied on the print medium from the first head and the second head;
A storage unit for storing color space correction information;
A drawing controller that corrects ink ejection from the first head and the second head based on the color space correction information;
With
The color management method includes:
a) discharging the ink from the first head and the second head toward the print medium based on the data of the test image, and causing the print medium to move relative to the first head and the second head; Moving in the printing direction and curing the ink applied on the print medium at the curing unit;
b) comparing the print result in the first area on the print medium with a partial image corresponding to the first area of the test image to obtain first color space correction information for the first area;
c) comparing the print result in the second area on the print medium with a partial image corresponding to the second area of the test image to obtain second color space correction information for the second area;
A color management method comprising: The color management method according to claim 1,
The printing apparatus has a structure similar to that of the first head, and a distance in the printing direction between the first curing unit and the curing unit is equal to a distance in the printing direction between the first head and the curing unit; A third head for printing on a third region adjacent to the second region on the print medium in a single pass, adjacent to the opposite side of the second head to the first head;
The color management method according to claim 1, wherein the first color space correction information is used for correcting ejection of ink from the first head and the third head. The color management method according to claim 1, wherein:
The scanning mechanism can move the print medium at a plurality of movement speeds relative to the first head and the second head;
The first color space correction information and the second color space correction information associated with each of the plurality of movement speeds by performing the steps a) to c) with respect to each of the plurality of movement speeds. A color management method characterized by: The color management method according to any one of claims 1 to 3,
The ink is an ultraviolet curable ink;
The color management method, wherein the curing unit irradiates an irradiation region extending in a direction perpendicular to the printing direction on the print medium. An inkjet printing apparatus,
Ink is ejected from the plurality of first ejection openings arranged in a predetermined arrangement direction intersecting the printing direction toward the printing medium, and printing is performed on the first area on the printing medium in one pass. A first head;
Ink is directed toward the print medium from a plurality of second ejection ports arranged adjacent to the first head in the arrangement direction and shifted from the first head in the printing direction and arranged in the arrangement direction. A second head that ejects and prints in a second region adjacent to the first region on the print medium in a single pass;
A scanning mechanism that moves the print medium relative to the first head and the second head in the printing direction;
A curing unit that is fixed in position with respect to the first head and the second head, and that cures the ink by passing over the ink applied on the print medium from the first head and the second head;
A storage unit for storing first color space correction information for the first region and second color space correction information for the second region;
A drawing control unit that corrects ink ejection from the first head based on the first color space correction information and corrects ink ejection from the second head based on the second color space correction information;
A printing apparatus comprising: The printing apparatus according to claim 5,
The scanning mechanism can move the print medium at a plurality of movement speeds relative to the first head and the second head;
The printing apparatus, wherein the storage unit stores the first color space correction information and the second color space correction information associated with each of the plurality of moving speeds. The printing apparatus according to claim 5 or 6,
The ink is an ultraviolet curable ink;
The printing apparatus, wherein the curing unit irradiates an irradiation region extending in a direction perpendicular to the printing direction on the print medium.

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