Printing apparatus, its control method, and computer program

Abstract

To provide a printer which improves color calibration of an image.SOLUTION: A printer 10 comprises: a first nozzle 24a which prints an image on a printing medium on the basis of image data with ink in a prescribed fundamental color and a second nozzle 24b which prints an image on the printing medium on the basis of the image data with ink in a specific color different from the fundamental color; a first channel 13a which supplies the ink in the fundamental color to the first nozzle; a second channel 13b which supplies the ink in the specific color to the second nozzle; and a control device 50. The control device executes a first acquisition operation of acquiring a first printing color region being a region including the specific color in the printing color region being the region in a prescribed color space occupied by a color value of colors that can be printed with ink in the specific color and ink in the fundamental color before the ink in the specific color is filled to the second channel, and a printing operation of printing on the printing medium a patch of the first image color value being the color value in the first printing color region in the color values included in image data after the first acquisition operation and after the ink in the specific color is filled to the second channel.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] This invention relates to a printing apparatus, a control method thereof, and a computer program. [Background technology]

[0002] As a conventional printing apparatus, for example, the color processing apparatus described in Patent Document 1 is known. This color processing apparatus acquires an evaluation value for the difference between the image color values ​​of an image and a predetermined color gamut of an output device that outputs the image. If the evaluation value is greater than a predetermined threshold, the apparatus converts the image color values ​​to output color values ​​so that the image color values ​​fit within the color gamut of the output device. On the other hand, if the evaluation value is less than the predetermined threshold, the apparatus acquires the image color values ​​as output color values ​​without conversion. The apparatus then generates a color profile that associates the image color values ​​with the output color values ​​and performs color conversion processing of the image data based on this color profile. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2008-123291 [Overview of the project] [Problems that the invention aims to solve]

[0004] The above color processing device evaluates the difference between the image color values ​​and a predetermined color gamut of the output device, and performs color conversion based on this evaluation value. However, since the input color may not be reproducible within the predetermined color gamut, it is conceivable to use a different special color in the output device. In this case, the selection of a special color that improves image reproducibility is required.

[0005] In view of these circumstances, the present invention aims to provide a printing apparatus, a control method thereof, and a computer program that can improve the reproducibility of images using special colors. [Means for solving the problem]

[0006] A printing apparatus according to one aspect of the present invention includes a first nozzle for printing an image on a printing medium based on image data using a predetermined basic color ink, a second nozzle for printing the image on the printing medium based on image data using a spot color ink different from the basic color, a first channel for supplying the basic color ink to the first nozzle, a second channel for supplying the spot color ink to the second nozzle, and a control device, wherein the control device performs a first acquisition operation to acquire a first printing color gamut which is the region containing the spot color among the printing color gamut which is the region in a predetermined color space in which the color values ​​of printable colors using the spot color ink and the basic color ink occupy, before the second channel is filled with the spot color ink, and a printing operation which, after the first acquisition operation and after the second channel is filled with the spot color ink, prints a patch of a first image color value which is a color value within the first printing color gamut among the color values ​​included in the image data onto the printing medium.

[0007] A method for controlling a printing apparatus according to one aspect of the present invention comprises: a first nozzle for printing an image on a printing medium based on image data using a predetermined basic color ink; a second nozzle for printing the image on the printing medium based on image data using a spot color ink different from the basic color; a first channel for supplying the basic color ink to the first nozzle; and a second channel for supplying the spot color ink to the second nozzle, wherein the method for controlling a printing apparatus includes: a first acquisition operation to acquire a first printing color gamut, which is a region within a predetermined color space in which the color values ​​of printable colors using the spot color ink and the basic color ink occupy, before the second channel is filled with the spot color ink; and a printing operation to print a patch of a first image color value, which is a color value within the first printing color gamut among the color values ​​included in the image data, onto the printing medium after the first acquisition operation and after the second channel is filled with the spot color ink.

[0008] A computer program according to an aspect of the present invention includes a first nozzle that prints an image on a printing medium based on image data using ink of a predetermined basic color, a second nozzle that prints the image on the printing medium based on the image data using ink of a special color different from the basic color, a first flow path that supplies the ink of the basic color to the first nozzle, and a second flow path that supplies the ink of the special color to the second nozzle. The computer program causes the printing apparatus to execute a first acquisition operation of acquiring a first printing color gamut, which is a region including the special color, in a printing color gamut that is a region occupied by color values of printable colors by the ink of the special color and the ink of the basic color in a predetermined color space, before the second flow path is filled with the ink of the special color, and a printing operation of printing a patch of a first image color value, which is a color value within the first printing color gamut among the color values included in the image data, on the printing medium after the first acquisition operation and after the second flow path is filled with the ink of the special color.

Advantages of the Invention

[0009] According to the present invention, it is possible to provide a printing apparatus, a control method thereof, and a computer program that can improve color calibration of an image using a special color.

[0010] The above objects, other objects, features, and advantages of the present invention will become apparent from the following detailed description of preferred embodiments with reference to the accompanying drawings.

Brief Description of the Drawings

[0011] [Figure 1] FIG. 1 is a schematic top view of a printing apparatus according to an embodiment and a modification of the present invention. [Figure 2] FIG. 2 is a schematic bottom view of a head. [Figure 3] FIG. 3 is a block diagram showing a functional configuration of a printing apparatus. [Figure 4] FIG. 4 is a flowchart showing an example of a control method of a printing apparatus according to an embodiment. [Figure 5] FIG. 5 is a diagram showing an image of image data acquired by the first acquisition operation in FIG. 4. [Figure 6] Figure 6 shows the color gamut of the image in Figure 5, represented in the L*a*b* color space. [Figure 7] Figure 7 shows the print color gamut of red represented in the L*a*b* color space. [Figure 8] Figure 8 shows the image color gamut of Figure 6 and the print color gamut of Figure 7 superimposed in the L*a*b* color space. [Figure 9] Figure 9 shows the printable medium on which the patch chart was printed using the printing operation shown in Figure 4. [Figure 10] Figure 10 is a flowchart showing an example of a control method for a printing apparatus according to Modification 1. [Figure 11] Figure 11 shows the printable medium on which the patch chart was printed using the printing operation shown in Figure 10. [Figure 12] Figure 12 shows a patch chart printed by the printing device according to Modification Example 2. [Figure 13] Figure 13 shows the print head of the printing device according to Modification 4, and the patch chart printed by the print head. [Figure 14] Figure 14 shows the print head of the printing device according to Modification 5, and a portion of the patch chart printed by the print head. [Figure 15] Figure 15 shows the print head of the printing apparatus according to Modification 6, and a portion of the patch chart printed by the print head. [Figure 16] Figure 16 shows a patch chart printed by the printing device according to the modified example 8. [Figure 17] Figures 17(a) and 17(b) show the print head of the printing apparatus according to Modification 9 and a portion of the patch chart printed by the print head. [Figure 18] Figures 18(a) and 18(b) show the print head of the printing apparatus according to Modification 10 and a portion of the patch chart printed by the print head. [Figure 19] Figure 19 shows an image of the image data acquired by the printing device according to the modified example 11. [Figure 20] Figure 20 shows a patch chart printed based on the image data in Figure 19. [Figure 21] Figure 21 is a schematic diagram of a printing apparatus according to modified example 10, viewed from the left. [Modes for carrying out the invention]

[0012] <Printing device configuration> A printing apparatus 10 according to one embodiment of the present invention, as shown in Figure 1, is a device that ejects ink from the nozzles 24 (Figure 2) of the head 20 onto a printing medium A, and prints an image on the printing medium A using the ink. Below, an example of applying the printing apparatus 10 to an inkjet printer will be described, but the printing apparatus 10 is not limited to this. The printing medium A is, for example, a sheet of paper or cloth.

[0013] The printing apparatus 10 is a serial head type and includes a plurality of heads 20, a platen 11, a plurality of tanks 12, a transport device 30, and a scanning device 40. The first direction in which the transport device 30 transports the printing medium A is referred to as the front-to-back direction. The second direction intersecting (e.g., perpendicular to) the first direction is referred to as the left-to-right direction. The direction intersecting (e.g., perpendicular to) the front-to-back direction and the left-to-right direction is referred to as the up-and-down direction. However, the arrangement of the printing apparatus 10 is not limited to this. The printing apparatus 10 may also be a line head type. In this case, the printing apparatus 10 does not include a scanning device 40, and the heads 20 do not move and have dimensions longer than the length of the printing area of ​​the printing medium A in the left-to-right direction.

[0014] The multiple heads 20 include a first head 21, a second head 22, and a third head 23. The platen 11 has a flat upper surface and defines the distance between the printing medium A placed on its upper surface and the lower surface of the head 20 provided opposite it. The tanks 12 are containers for storing ink, and their number is equal to or greater than the number of ink types. For example, the tanks 12 have four first tanks 12a, each storing one of four basic color inks, one or more second tanks 12b, each storing a spot color ink, and one or more third tanks 12c, each storing a base color ink.

[0015] Examples of basic ink colors include cyan, yellow, magenta, and black. Special inks are those of different colors from the basic inks, such as red, green, and blue. An example of a base color ink is white.

[0016] The first tank 12a stores the base color ink and is connected to the first head 21 via the first channel 13a. The base color ink is supplied from the first tank 12a to the first head 21 via the first channel 13a. The second tank 12b is connected to the second head 22 via the second channel 13b. When the special color ink is stored in the second tank 12b, the special color ink flows from the second tank 12b to the second channel 13b, fills it, and is supplied to the head 20. Before the special color ink is stored in this second tank 12b, it is filled with a preservative liquid different from the special color ink. The third tank 12c is connected to the third head 23 via the third channel 13c. The base color ink is supplied from the third tank 12c to the third head 23 via the third channel 13c. The first channel 13a, the second channel 13b, and the third channel 13c are, for example, rubber tubes or plastic tubes, and are preferably made of materials that are resistant to bending.

[0017] The conveying device 30 includes, for example, two sets of conveying rollers 31 and a conveying motor 32 (Figure 3). The two sets of conveying rollers 31 are arranged in the front-to-back direction with the platen 11 in between them. Each conveying roller 31 has an axis that extends in the left-to-right direction. Each set of conveying rollers 31 is arranged vertically with the printing medium A in between them. One of the conveying rollers 31 in each set is connected to the conveying motor 32. The conveying rollers 31 rotate around their axis when driven by the conveying motor 32, and convey the printing medium A in the front-to-back direction on the platen 11.

[0018] The scanning device 40 includes a carriage 41, two guide rails 42, a scanning motor 43, and an endless belt 44. The two guide rails 42 extend horizontally above the platen 11 so as to sandwich the head 20 between them in the front-rear direction. The carriage 41 mounts the head 20 and is supported by the two guide rails 42 so as to be movable in the left-right direction. The endless belt 44 extends horizontally and is attached to the carriage 41, and is also attached to the scanning motor 43 via a pulley 45. When the scanning motor 43 is driven, the endless belt 44 travels, and the carriage 41 reciprocates horizontally along the guide rails 42. This causes the carriage 41 to move the head 20 horizontally.

[0019] <Head> The carriage 41 is provided with a plurality of heads 20, as shown in Figure 2. The plurality of heads 20 include, for example, two first heads 21, two second heads 22, and two third heads 23. The two first heads 21 include a right first head 21 and a left first head 21, the two second heads 22 include a right second head 22 and a left second head 22, and the two third heads 23 include a right third head 23 and a left third head 23.

[0020] For example, the second head 22 on the right, the first head 21 on the right, and the third head 23 on the right are arranged in a row with spacing between them in the front-to-back direction, in this order from the front. The second head 22 on the left, the first head 21 on the left, and the third head 23 on the left are arranged in a row with spacing between them in the front-to-back direction, in this order from the front. These heads 20 are arranged in a staggered pattern such that the first head 21 on the right is positioned in front of the first head 21 on the left, the second head 22 on the right is positioned in front of the second head 22 on the left, and the third head 23 on the right is positioned in front of the third head 23 on the left.

[0021] Each head 20 has a flow path forming body and a plurality of nozzles 24, and the flow path forming body is composed of a laminate of a plurality of plates including a nozzle plate 27. The nozzle plate 27 has a flat plate shape, and its lower surface constitutes the lower surface of the head 20. The nozzles 24 open to the lower surface of the nozzle plate 27, which is the lower surface of the head 20. The plurality of nozzles 24 include a first nozzle 24a of the first head 21, a second nozzle 24b of the second head 22, and a third nozzle 24c of the third head 23. The plurality of nozzles 24 are arranged in a nozzle row in the front-to-back direction on each head 20. The plurality of nozzle rows are provided in parallel on each head 20 with spacing in the left-to-right direction. The nozzle row of the first head 21 has first nozzle rows 21a to 21d, the nozzle row of the second head 22 has second nozzle rows 22a to 22d, and the nozzle row of the third head 23 has third nozzle rows 23a to 23d.

[0022] The first nozzle 24a of the first nozzle row 21a is connected to the first tank 12a of cyan ink via the first channel 13a, and is capable of ejecting cyan ink. The first nozzle 24a of the first nozzle row 21b is connected to the first tank 12a of magenta ink via the first channel 13a, and is capable of ejecting magenta ink. The first nozzle 24a of the first nozzle row 21c is connected to the first tank 12a of yellow ink via the first channel 13a, and is capable of ejecting yellow ink. The first nozzle 24a of the first nozzle row 21d is connected to the first tank 12a of black ink via the first channel 13a, and is capable of ejecting black ink. The third nozzles 24c of the third nozzle rows 23a to 23d are connected to the third tank 12c of white ink via the third channel 13c, and are capable of ejecting white ink.

[0023] The second nozzles 24b of the second nozzle rows 22a to 22d are connected to the second tank 12b of the special color ink via the second channel 13b. When the special color ink is stored in the second tank 12b, the special color ink is supplied from the second tank 12b via the second channel 13b, and the second nozzles 24b become capable of dispensing the special color ink. Here, the second nozzles 24b of the second nozzle row 22a, the second nozzles 24b of the second nozzle row 22b, the second nozzles 24b of the second nozzle row 22c, and the second nozzles 24b of the second nozzle row 22d may dispensing different types of special color ink. For example, the second nozzle 24b of the second nozzle row 22a may be capable of ejecting red ink, the second nozzle 24b of the second nozzle row 22b may be capable of ejecting green ink, the second nozzle 24b of the second nozzle row 22c may be capable of ejecting blue ink, and the second nozzle 24b of the second nozzle row 22d may be capable of ejecting gold ink. Alternatively, the second nozzles 24b of the second nozzle row 22a, 24b of the second nozzle row 22b, 24b of the second nozzle row 22c, and 24b of the second nozzle row 22d may each eject ink of the same type. In this case, the printing apparatus 10 may be provided with one type of second tank 12b, and the second nozzles 24b of the second nozzle rows 22a to 22d may be connected to this second tank 12b and each may eject ink of the same type.

[0024] Furthermore, as shown in Figure 3, the head 20 has a plurality of drive elements 25. The drive elements 25 are piezoelectric elements, heating elements, electrostatic actuators, etc., and are provided for each nozzle 24, applying pressure to the ink to eject the ink from the nozzle 24.

[0025] <Control devices, display devices, input devices> As shown in Figure 3, the printing apparatus 10 further comprises a display device 14, an input device 15, a colorimeter 16, and a control device 50. The control device 50 is, for example, a computer and has an interface 51, an arithmetic unit 52, and a storage unit 53. The interface 51 receives various data, such as image data, from external devices B such as a computer, camera, communication network, recording medium, display, and printer. The image data is raster data that shows an image to be printed on the printing medium A. The control device 50 may consist of a single device, or multiple devices may be distributed and configured to cooperate in the operation of the printing apparatus 10.

[0026] The storage unit 53 is a memory accessible from the arithmetic unit 52 and includes RAM and ROM. The RAM temporarily stores various types of data, such as data received from an external device B, such as image data, and data converted by the arithmetic unit 52. The ROM stores computer programs for various data processing, and predetermined data such as predetermined correspondences. The computer programs may be stored on an external storage medium different from the storage unit 53 that is accessible from the arithmetic unit 52, such as a CD-ROM.

[0027] The arithmetic unit 52 includes, for example, a processor such as a CPU and at least one circuit such as an integrated circuit such as an ASIC. The arithmetic unit 52 controls each part by executing a computer program and performs various operations such as printing. Details of the various operations will be described later.

[0028] Such a control device 50 is electrically connected to the display device 14 and the input device 15. The display device 14 is, for example, a display, which is controlled by the control device 50 to display an image C to be printed by a printing operation. The input device 15 is, for example, a button and a mouse, which is operated by the user to input data to the control device 50. The input device 15 may be a touch panel integrated with the display device 14. The input device 15 may be an interface 51 to which information is input from the outside. The colorimeter 16 is, for example, a spectrophotometer, which measures the color of the patches on the patch chart P printed on the printing medium A and inputs the measured color to the control device 50.

[0029] Furthermore, the control device 50 is electrically connected to the transport motor 32 of the transport device 30 via the transport drive circuit 33, and controls the drive of the transport motor 32. This controls the transport of the printing medium A by the transport device 30. In addition, the control device 50 is electrically connected to the scanning motor 43 of the scanning device 40 via the scanning drive circuit 46, and controls the drive of the scanning motor 43. This controls the movement of the head 20 by the scanning device 40.

[0030] Furthermore, the control device 50 is electrically connected to the drive element 25 via the head drive circuit 26. The control device 50 outputs a control signal for the drive element 25 to the head drive circuit 26, and the head drive circuit 26 generates a drive signal based on the control signal and outputs it to the drive element 25. The drive element 25 is driven in accordance with the drive signal, and ink is ejected from the nozzle 24.

[0031] <Printing operation> In such a printing apparatus 10, the control device 50 acquires image data of image C and executes a printing operation based on the image data. For example, in the pass processing, the control device 50 moves the head 20 to the right or left while ejecting ink from the nozzles 24 of the head 20 onto the printing medium A. Then, in the transport processing, the control device 50 transports the printing medium A forward. In this way, the printing apparatus 10 repeatedly performs pass processing and transport processing alternately, carrying out the printing operation to print an image on the printing medium A with ink.

[0032] If no background is printed on the printing medium A before printing the image, the control device 50 ejects basic color ink from the first nozzle 24a of the first head 21 and spot color ink from the second nozzle 24b of the second head 22, based on the image data of the image, to form the image on the printing medium A. As a result, the image C is printed on the printing medium A using the basic color and spot color inks.

[0033] Furthermore, when printing a background on the printing medium A before printing the image, the control device 50 acquires the area of ​​the background based on the image data of the image so that the image is printed on the background. The control device 50 then ejects the background color ink from the third nozzle 24c of the third head 23 onto the printing medium A, forming a background on the printing medium A with the background ink. Then, based on the image data of the image, the control device 50 ejects the basic color ink from the first nozzle 24a of the first head 21 and the spot color ink from the second nozzle 24b of the second head 22 to form the image C on the background. As a result, the image C is printed on the printing medium A via the background using the basic color and spot color inks.

[0034] <Control method for printing devices> The control method of the printing device 10 is executed by the control device 50 along, for example, the flowchart showing an example of the control method in FIG. 4. For example, the control device 50 acquires the image data of the image C for printing the image C in FIG. 5 from the external device B (step S1). The image C has a plurality of pixels C0 divided per unit area. The image data includes the color values of the pixels C0. This color value is represented by, for example, color coordinates in a device-dependent color space, such as RGB values in the RGB color space. This RGB value represents one color, for example, by a combination of a 256-level red color value, a 256-level green color value, and a 256-level blue color value.

[0035] Then, the control device 50 converts the RGB value of the pixel C0 into a Lab value based on a predetermined correspondence relationship between the RGB value and the Lab value. The Lab value is device-independent L * , * , , * , * , * , * , * , * , * , * ,

[0036] , * , * , * , * , a * b * It is a color value in the color space, where L represents lightness, and a and b are coordinates representing hue and chroma. For example, as shown in FIG. 6, the image color value E, which is the Lab value of all the pixels C0 in the image C, is L * a * b * Drawn in the color space. This L * a * b * In the color space, the image color gamut D is the area occupied by the image color value E of all the pixels C0 of the image C, and is L * a * b * It is a closed region in the color space.

[0036] The image C in FIG. 5 has a pale orange part C1 of the face and hands, a light gray part C2 of the clothes, a dark gray part C3 of the clothes, a black part C4 of the hair and eyes, a red part C5 of the mouth and clothes, and a blue part C6 of the hairpin. In contrast, the L in FIG. 6 * a * b *In the color space, the color gamuts D1 to D6, which represent the color values ​​of these sub-parts C1 to C6, are located within the image color gamut D. Each of the color gamuts D1 to D6 has one or more color values.

[0037] Next, the control device 50 performs a first acquisition operation (step S2) to acquire the first print color gamut F1, which is the region of the print color gamut F that includes the spot color, before the spot color ink is filled into the second flow path 13b.

[0038] The control device 50 obtains the color values ​​of predetermined basic colors from the storage unit 53 and, based on those color values, obtains the basic color value G2, which is the color value of a printable color of the head 20 using the basic color ink. For example, if the printing device 10 is equipped with cyan, magenta, yellow, and black inks, the basic color value G2 is the color value of a color that includes at least one of these four colors. The basic color value G2 includes the color values ​​of individual colors cyan, magenta, yellow, and black, and the color values ​​of mixed colors obtained by combining two or more of these colors. The basic color value G2 is represented, for example, by a CMYK value, which is a color coordinate in the device-dependent CMYK space. A CMYK value represents a single color by a combination of the color values ​​of cyan, magenta, yellow, and black in a predetermined gradation.

[0039] If the color value of a spot color is stored in the storage unit 53, the control device 50 retrieves the color value of the spot color as the spot color value G1 from the storage unit 53. If the color value of a spot color is not stored in the storage unit 53, the control device 50 retrieves the color value of the spot color as the spot color value G1 from the input device 15 and interface 51, etc. The spot color value G1 is represented by RGB values ​​or CMYK values, etc.

[0040] The control device 50 converts the CMYK value of the basic color value G2 to a Lab value based on a predetermined correspondence between CMYK values ​​and Lab values, and stores the correspondence between CMYK values ​​and Lab values ​​for the basic color value G2 in the storage unit 53. Furthermore, if the spot color value G1 is defined by RGB values, the control device 50 converts the RGB value of the spot color to a Lab value based on a predetermined correspondence between RGB values ​​and Lab values. The device converts the CMYK value of a spot color to a Lab value based on a predetermined correspondence between CMYK values ​​and Lab values. The control device 50 then stores the correspondence between the RGB value or CMYK value and the Lab value for the spot color value G1 in the storage unit 53.

[0041] As shown in Figure 7, the control device 50 sets the basic color value G2 to L * a * b * It draws in the color space. The control device 50 controls this L * a * b * The region occupied by all basic color values ​​G2 in the color space is obtained as the second printing color gamut F2. The second printing color gamut F2 is L * a * b * A closed region in the color space that contains all the basic color values ​​G2.

[0042] Furthermore, in the case of the red spot color, the control device 50 sets the spot color value G1, which is the Lab value of the red spot color, to L * a * b * The image is drawn in the color space. Then, the control device 50, based on the second print color gamut F2 and the spot color value G1, L * a * b *In the color space, the region extending from the second printing color space F2 by the spot color value G1 is acquired as the first printing color space F1. The first printing color space F1 is, for example, the space enclosed by a straight line drawn from the spot color value G1 to the base color space F0, and the base color space F0, and is the largest space within this space. The color values ​​of the first printing color space F1 include the spot color value G1 of a single spot color red, and the color values ​​of mixed colors that are combinations of base colors and spot colors. The control device 50 then acquires the region combining the second printing color space F2 and the first printing color space F1 as the printing color space F. This printing color space F is the color value of the colors that the head 20 can print with spot color inks and base color inks in a predetermined color space, for example, L * a * b * It is a region within the color space.

[0043] Next, the control device 50 determines whether or not the special ink has been filled into the second channel 13b (step S3). For example, this determination is made based on the ink introduction process. The ink introduction process is a process in which the storage liquid filling the second head 22 is replaced with the special ink by purging. Therefore, if purging is performed to discharge the storage liquid from the second nozzle 24b of the second head 22, the control device 50 determines that the special ink introduction process has been performed and that the special ink has been filled into the second channel 13b (step S3: YES). On the other hand, if purging is not performed to discharge the storage liquid from the second nozzle 24b of the second head 22, the control device 50 determines that the special ink introduction process has not been performed and that the special ink has not been filled into the second channel 13b (step S3: NO).

[0044] Next, after the first acquisition operation and after the second channel 13b has been filled with the special color ink (step S3: YES), the control device 50 performs a printing operation to print a patch of the first image color value E1, which is a color value within the first print color gamut F1 among the color values ​​included in the image data, onto the printing medium A (step S4).

[0045] Before this printing operation, the user stores the special color ink in the second tank 12b. This allows the special color ink to flow from the second tank 12b into the second flow path 13b, filling it and supplying it to the second nozzle 24b of the second head 22. This makes the special color ink available for ejection from the second nozzle 24b. The control device 50 also generates image data of the patch chart P, as shown in the example in Figure 9. The patch chart P has a plurality of print patches P0 and one or more first image patches P1. The patches may be, for example, rectangular color samples, of a size that allows for color measurement by the colorimeter 16, and may be predetermined according to the resolution of the colorimeter 16.

[0046] In generating image data for patch chart P, the control device 50 acquires the print color value, which is the color value of print patch P0. Here, the control device 50 acquires the print color gamut F in predetermined increments for each of L, a, and b, and combines these increments to acquire the Lab value of the print color gamut F as the print color value of print patch P0. The print color value is a color value that represents the print color gamut F in steps, and is a color value obtained by changing the print color gamut F in predetermined increments, and is different from one another. The control device 50 also acquires the first image color value E1, which is the color value of the first image patch P1. Here, as shown in Figure 8, the control device 50 acquires L * a * b * Among the image color values ​​E in the image color gamut D of the color space, the image color value E that is included in the first print color gamut F1 is obtained as the first image color value E1. Since the first image color value E1 is included in the print color gamut F, the print patch P0 includes the first patch P01, which is the same color print patch P0 as the first image patch P1.

[0047] As shown in Figure 8, if the image color gamut D includes image color values ​​E outside the print color gamut F, the control device 50 performs a color compression operation such as gamut mapping on those image color values ​​E. For example, in a color compression operation, the control device 50 performs L * a * b *In the color space, an image color value E outside the print color gamut F is converted to the closest color value within the print color gamut F. The converted color value is the intersection point of the perpendicular line drawn from the image color value E on the contour of the print color gamut F. In this way, the color compression operation converts an image color value E outside the print color gamut F to a color value within the print color gamut F. The control device 50 then acquires the image color value E included in the first print color gamut F1 from among the image color values ​​E in the image color gamut D as the first image color value E1.

[0048] Furthermore, the control device 50 arranges the print patch P0 and the first image patch P1 on the patch chart P so that the print patch P0 and the first image patch P1 are printed on a single printing medium A. Here, the control device 50 arranges the first patch P01 and the first image patch P1 on the patch chart P such that the printing position of the first patch P01, which is a print patch P0 of the same color as the first image patch P1, and the printing position of the first image patch P1 on the printing medium A are different from each other in the front-to-back direction, the left-to-right direction, or both the front-to-back and left-to-right directions.

[0049] In this way, the control device 50 prints the patch chart P onto the printing medium A based on the image data in which the color values ​​and arrangement of the print patch P0 and the first image patch P1 have been determined. During this printing, the control device 50 converts the Lab values ​​of the print color values ​​in the print color gamut F and the first image color value E1 of the first image patch P1 into color values ​​in CMYK and spot colors based on a predetermined correspondence. The converted color values ​​of the print color values ​​and the first image color value E1 are color coordinates in a color space with cyan, magenta, yellow, black and spot colors as axes, and are represented by a single color value formed by a combination of the cyan, magenta, yellow, black and spot color values ​​of a predetermined gradation. As a result, the print patch P0 and the first image patch P1 are printed in single colors of cyan, magenta, yellow, black and spot colors, or in mixed colors of at least two of these colors.

[0050] In the example in Figure 9, print patch P0 includes print patch group P0(D1), print patch group P0(D2), print patch group P0(D3), print patch group P0(D4), print patch group P0(D5), and print patch group P0(D6). Print patch group P0(D1) contains one or more print patches P0, each print patch P0 has a color value in the color gamut D1, and the print color values ​​of the multiple print patches P0 are different color values ​​in the color gamut D1. Print patch groups P0(D2~D6) are similar to print patch group P0(D1) in that they contain one or more print patches P0, each print patch P0 has a color value in the color gamut D2~D6, and the print color values ​​of the multiple print patches P0 are different color values ​​in the color gamut D2~D6.

[0051] Furthermore, the first image patch group P1(D5) includes one or more first image patches P1. Each first image patch P1 has a first image color value E1 in the color gamut D5, and the first image color values ​​E1 of multiple first image patches P1 are different color values ​​in the color gamut D5. The print patch group P0(D5) includes a first patch P01, which is a print patch P0 of the same color as the first image color value E1 of the first image patch group P1(D5).

[0052] The first image patch group P1(D5) and the print patch group P0(D5) are printed on the same print medium A. The first image patch group P1(D5) is positioned behind the print patch group P0(D5) in the front-to-back direction and to the right of the print patch group P0(D5) in the left-to-right direction. Therefore, the positions of the first image patch P1 of the first image patch group P1(D5) and the first patch P01 of the print patch group P0(D5) on the print medium A are different from each other.

[0053] The control device 50 then measures the color of, for example, the printed patch P0 and the first image patch P1 of the patch chart P printed on the printing medium A using the colorimeter 16, and stores the measured color values ​​in the storage unit 53, associating them with the color values ​​of each patch. Based on this correspondence, the control device 50 creates a calibration profile for calibrating the color of the printed image C to the target color. Here, since the first image patch group P1(D5) and the printed patch group P0(D5) have patches of the same color, multiple measured color values ​​are obtained for a single color value. In this case, the control device 50 creates a calibration profile using the average value of the multiple measured color values.

[0054] Thus, the more patches of the same color there are, the lower the color measurement error. Therefore, since there are more patches of the color gamut D5, which is used in the image and includes spot colors, than patches of other colors, the color measurement error of the patches containing spot colors can be reduced. Furthermore, since the positions of the first image patch P1 and the first patch P01, which are the same color as each other, differ in the front-to-back and left-to-right directions on the printing medium A, the error in the color measurement value according to the position on the printing medium A can be reduced. As a result, the accuracy of the calibration profile using spot colors in addition to predetermined basic colors is improved, and the reproducibility of image C can be improved.

[0055] <Example 1> In the printing apparatus 10 according to Modification 1, in the above embodiment, the control device 50 performs a second acquisition operation to acquire the second printing color gamut F2, which is the region of the printing color gamut F that does not contain the spot color, before the spot color ink is filled into the second flow path 13b. In the printing operation, the control device 50 prints a patch of the second image color value E2, which is a color value within the second printing color gamut F2 among the color values ​​included in the image data, and a patch of the first image color value E1.

[0056] For example, the control method for the printing device 10 is executed by the control device 50 according to the flowchart shown in Figure 10, for example. In this flowchart of Figure 10, the process of step S5 is executed between steps S2 and S3 in the flowchart of Figure 4.

[0057] Specifically, the control device 50 performs a second acquisition operation (step S5). In the second acquisition operation, the control device 50 performs L as shown in Figure 8. * a * b * In the color space, the region occupied by the Lab values ​​of all basic colors, excluding the Lab values ​​of spot colors, is obtained as the second printing color gamut, F2.

[0058] Next, the control device 50 performs a printing operation (step S4). In the printing operation, the control device 50 generates image data of the patch chart P shown in the example in Figure 9. The patch chart P has a plurality of print patches P0, one or more first image patches P1, and one or more second image patches P2. As described above, the control device 50 obtains the print color values ​​of the print patches P0 and the first image color values ​​E1 of the first image patches P1. Also, as shown in Figure 8, the control device 50 L * a * b * Of the image color values ​​E in the image color space D, the image color value E included in the second print color space F2 is acquired as the second image color value E2. Since the second image color value E2 is included in the print color space F, print patch P0 includes a second patch P02 which is a print patch P0 of the same color as the second image color value E2 of the second image patch P2. If the image color space D includes an image color value E outside the print color space F, the control device 50 performs a color compression operation on that image color value E before acquiring the second image color value E2.

[0059] Furthermore, the control device 50 arranges the print patch P0, the first image patch P1, and the second image patch P2 on the patch chart P so that they are printed on a single print medium A. Here, the control device 50 arranges the second patch P02 and the second image patch P2 on the patch chart P such that the printing position of the second patch P02, which is a print patch P0 of the same color as the second image patch P2, and the printing position of the second image patch P2 on the print medium A are different from each other in the front-to-back direction, the left-to-right direction, and both the front-to-back and left-to-right directions.

[0060] In this way, the control device 50 prints the patch chart P onto the printing medium A based on image data in which the color values ​​and arrangement of the print patch P0, the first image patch P1, and the second image patch P2 have been determined. During this printing, the control device 50 converts the Lab values ​​of the print color values ​​of the print color gamut F, the first image color value E1 of the first image patch P1, and the second image color value E2 of the second image patch P2 into CMYK and spot color values ​​based on a predetermined correspondence. As a result, these patches are printed in single colors of cyan, magenta, yellow, black, and spot colors, or in mixed colors of at least two of these colors.

[0061] In the example in Figure 11, print patch P0 includes print patch group P0(D1), print patch group P0(D2), print patch group P0(D3), print patch group P0(D4), print patch group P0(D5), and print patch group P0(D6). Similarly, second image patch P2 includes second image patch group P2(D1), second image patch group P2(D2), second image patch group P2(D3), second image patch group P2(D4), and second image patch group P2(D6). Second image patch group P2(D1) contains one or more second image patches P2. Each second image patch P2 has a second image color value E2 in the color gamut D1, and the second image color values ​​E2 of multiple second image patches P2 are different color values ​​in the color gamut D1. Print patch group P0(D1) includes a second patch P02 which is a print patch P0 of the same color as the second image color value E2 of the second image patch group P2(D1). Similarly, the second image patch groups P2(D3), P2(D4), and P2(D6) include one or more second image patches P2 of the same color as the second patch P02, just like the second image patch group P2(D1).

[0062] The second image patch group P2(D1) and the print patch group P0(D1) are printed on the same print medium A. The second image patch group P2(D1) is positioned behind the print patch group P0(D1) in the front-to-back direction and to the left of the print patch group P0(D1) in the left-to-right direction. Therefore, the positions of the second image patch P2 of the second image patch group P2(D1) and the second patch P02 of the print patch group P0(D1) on print medium A are different from each other. Similarly, for the second image patch groups P2(D2)~(D4) and (D6), the positions of the second image patch P2 and the second patch P02 of the same color on print medium A are different from each other.

[0063] Thus, the second image patch group P2(D1)~(D4) and (D6) have a second patch P02 of the same color in print patch P0, and the first image patch group P1(D5) has a first patch P01 of the same color in print patch P0. Therefore, multiple colorimetric values ​​are obtained for each color. Since there are more colorimetric values ​​for each of these colors than for other colors, the error in colorimetric measurement of the patches can be reduced. Furthermore, since the positions of the second image patches P2 and second patch P02 of the same color on the print medium A differ in the front-to-back and left-to-right directions, the error in colorimetric values ​​according to the position on the print medium A can be reduced. As a result, the accuracy of the calibration profile using spot colors in addition to predetermined basic colors can be improved, thereby improving the reproducibility of image C.

[0064] <Modification 2> In the printing apparatus 10 according to Modification Example 2, the number of patches per color is greater for the first image color value E1 than for the second image color value E2, compared to Modification Example 1. For example, as shown in Figure 12, the patch chart P includes print patch P0, first image patch group P1(D5), second image patch group P2(D1), second image patch group P2(D2), second image patch group P2(D3), second image patch group P2(D4), and second image patch group P2(D6).

[0065] In patch chart P, the number of first image patch groups P1(D5) is greater than the number of second image patch groups P2(D1), P2(D2), P2(D3), P2(D4), and P2(D6), for example, there are two of them in patch chart P. In addition, printed patch P0 includes a first patch P01 of the first image patch group P1(D5) which is the same color as the first image patch P1, and a second patch P02 of the second image patch groups P2(D2)-(D4) and (D6) which is the same color as the second image patch P2.

[0066] For one first image color value E1, there are three patches of the same color: one first patch P01 and two first image patches P1. In contrast, for one second image color value E2, there are two patches of the same color: one second patch P02 and one second image patch P2. Therefore, the number of patches per color is greater for the first image patch P1 of the first image color value E1 than for the second image patch P2 of the second image color value E2. As a result, the number of colorimetric values ​​per color is greater for the first image color value E1 than for the second image color value E2, and the error in the colorimetric value relative to the first image color value E1 due to its position on the printing medium A can be reduced. This improves the accuracy of the calibration profile using these colorimetric values, thereby improving the reproducibility of image C using the calibration profile.

[0067] <Variation 3> In the printing apparatus 10 according to the modified example 3, in the above embodiment, the control device 50 performs a second acquisition operation to acquire the second printing color gamut F2, which is the region of the printing color gamut F that does not contain the spot color, before the spot color ink is filled into the second flow channel 13b. In the printing operation, the control device 50 prints the patch of the first image color value E1, without printing the second image patch P2 of the second image color value E2 within the second printing color gamut F2 among the color values ​​included in the image data.

[0068] For example, in the patch chart P of Figure 11, among the first image patch P1, second image patch P2, and print patch P0, the second image patch P2 is not printed, while the first image patch P1 and print patch P0 are printed. In this case as well, a colorimetric value is obtained for the first image patch P1, which includes a spot color, and since the number of colorimetric values ​​per color is greater than that of other colors, the colorimetric error for the color including the spot color is reduced. Furthermore, since the positions of the first patch P01 and the first image patch P1 on the print medium A are different, the error in the colorimetric value depending on the position on the print medium A can be reduced. As the accuracy of the calibration profile using these colorimetric values ​​is improved, the reproducibility of image C by the calibration profile can be improved.

[0069] <Modification 4> In the printing apparatus 10 according to Modification 4, in the above embodiment and Modification 1-3, the control device 50 alternately repeats a pass process in the printing operation in which the carriage 41 moves the first nozzle 24a and the second nozzle 24b while ejecting ink from the first nozzle 24a and the second nozzle 24b onto the printing medium A, and a transport process in which the transport device 30 transports the printing medium A, and prints the first patch P01 and the first image patch P1 by different pass processes.

[0070] Specifically, as shown in Figure 13, the control device 50 prints the patch chart P onto the printing medium A using basic color inks and spot color inks, while repeatedly performing pass processing and transport processing during the printing operation. In this transport processing, the control device 50 transports the printing medium A so that the position of the head 20 relative to the printing medium A in the front-to-back direction is position (1). Then, the control device 50 executes pass processing 1 and moves the first head 21 to the range of the printing medium A. <1> While moving it to the right from above, the first nozzle 24a of the first head 21 ejects the basic color ink. This allows the range <1> The base color ink lands on the first image patch group P1(D5) in the image.

[0071] Next, in the transport process, the control device 50 transports the printing medium A forward so that the position of the head 20 relative to the printing medium A in the front-rear direction changes from position (1) to position (2). Then, the control device 50 executes pass processing 2. In this pass processing 2, the control device 50 moves the second head 22 within the range of the printing medium A. <1> While moving it to the left above, the special color ink is ejected from the second nozzle 24b of the second head 22. This allows the range <1> The spot color ink lands on the portion of the first image patch group P1(D5) in the image. Thus, through pass processing (1) and (2), the first image patch group P1(D5) is filled with the base color ink and the spot color ink within the range of print medium A. <1> It is printed on. Also, in pass processing 2, the control device 50 moves the first head 21 within the range of the printing medium A. <2> While moving it to the left above, the first nozzle 24a of the first head 21 ejects ink of the basic color based on the image data. This allows the range <2> The base color ink lands on the P0 portion of the printing patch.

[0072] Next, in the transport process, the control device 50 transports the printing medium A forward so that the position of the head 20 relative to the printing medium A in the front-rear direction changes from position (2) to position (3). Then, the control device 50 executes pass processing 3. In this pass processing 3, the control device 50 moves the second head 22 within the range of the printing medium A. <2> While moving it to the right from above, the special color ink is ejected from the second nozzle 24b of the second head 22. This allows the range <2> The spot color ink lands on the print patch P0 portion. In this way, through pass processing 2 and 3, the range <2> The range of print patch P0 in this case is the range of print medium A, determined by the base color ink and spot color ink. <2> It is printed on. Also, in pass processing 3, the control device 50 moves the first head 21 within the range of the printing medium A. <3> While moving it to the right above, the first nozzle 24a of the first head 21 ejects ink of the basic color based on the image data, thereby, <3> The base color ink lands on the P0 portion of the printing patch.

[0073] In this way, the control device 50 prints the patch chart P onto the printing medium A from the front, while repeatedly performing transport and path processing. Here, in path processing 4 following path processing 3, the range of the printing medium A <3> The spot color ink from the second nozzle 24b of the second head 22 lands on the print patch P0. As a result, pass processing 3 and 4, range <3> The range of print patch P0 in the print medium A is determined by the base color ink and the spot color ink. <3> It is printed in this range. The print patch P0 in this range includes the first patch P01 of the print patch group P0(D5). Thus, in the first image patch group P1(D5) and the print patch group P0(D5), the first image patch P1 and the first patch P01, which are the same color as each other, are printed by different pass processing. Therefore, the error in the colorimetric values ​​due to pass processing can be reduced by the colorimetric values ​​of the first patch P01 and the first image patch P1, which are the same color as each other. As the accuracy of the calibration profile using these colorimetric values ​​is improved, the reproducibility of image C by the calibration profile can be improved.

[0074] <Modification 5> In the printing apparatus 10 according to Modification 5, as in the above embodiment and Modification 1-4, the control device 50 causes the first patch P01 and the first image patch P1 to be printed using ink ejected from different nozzles 24 during the printing operation.

[0075] Specifically, for example, the control device 50 generates image data of the patch chart P shown in Figure 14. In this patch chart P, the print patch group P0(D5) contains multiple (for example, 32) first patches P01. The multiple first patches P01 have different color values ​​in the color gamut D5. For example, in the print patch group P0(D5), the 32 first patches P01 are arranged to the right in a column, and this column is arranged downwards. For example, the column starting from the first first patch P01, the column starting from the ninth first patch P01, the column starting from the seventeenth first patch P01, and the column starting from the twenty-fifth first patch P01 are arranged downwards in this order.

[0076] In contrast, the first image patch group P1(D5) contains multiple (for example, 32) first image patches P1. In the first image patch group P1(D5), the 32 first image patches P1 are arranged to the right in a column, and this column is arranged downwards. The arrangement order of the first patches P01 in the print patch group P0(D5) and the arrangement order of the first image patches P1 in the first image patch group P1(D5) are different in the front-to-back direction. For example, the column starting from the first first image patch P1 to the right, the column starting from the ninth first image patch P1 to the right, the column starting from the seventeenth first image patch P1 to the right, and the column starting from the twenty-fifth first image patch P1 to the right are arranged upwards in this order. The first first image patch P1 is the same color as the first first patch P01. The second and subsequent first image patches P1 are the same color as the second and subsequent first image patches P01, just like the first first image patch P1.

[0077] The control device 50 prints the patch chart P onto the printing medium A by repeatedly performing pass processing and transport processing based on the generated image data. Here, for example, in pass processing 3, the first patch P01, which is the last row in the print patch group P0 (D5), is hit by basic color ink from the first nozzle 24a of the left first head 21, which is positioned after the right first head 21. In contrast, in pass processing 1, the first image patch P1, which is the front row in the first image patch group P1 (D5), is hit by basic color ink from the right first head 21, which is positioned before the left first head 21. In this way, the first patch P01 and the first image patch P1, which are the same color, are hit by basic color ink ejected from different first nozzles 24a. Also, the first patch P01 and the first image patch P1, which are the same color, are hit by special color ink ejected from different second nozzles 24b, similar to the basic color.

[0078] While multiple nozzles 24 are arranged in the front-to-back direction in the print head 20, the arrangement order of the first patch P01 in the print patch group P0 (D5) and the arrangement order of the first image patch P1 in the first image patch group P1 (D5) are different in the front-to-back direction. As a result, the first patch P01 and the first image patch P1, which are the same color, are printed with ink ejected from different nozzles 24. Therefore, the error in the color measurement value by the nozzles 24 can be reduced by using the first patch P01 and the first image patch P1, which are the same color. This improves the accuracy of the calibration profile using the color measurement value, and thus improves the reproducibility of image C using the calibration profile.

[0079] <Variation 6> The printing apparatus 10 according to modified example 6 is equipped with a position sensor 47 that detects the positions of the first nozzle 24a and the second nozzle 24b in the left-right direction, as in the above embodiment and modified examples 1-5. In the printing operation, the control device 50 causes the first patch P01 and the first image patch P1 to be printed by ink ejected from the first nozzle 24a and the second nozzle 24b at different positions from each other.

[0080] Specifically, as shown in Figure 1, for example, the position sensor 47 is provided on the scanning device 40. For example, a linear encoder is used for the position sensor 47. In this case, the position sensor 47 has a home sensor 47a, a linear scale 47b, and a scale sensor 47c, and detects the position of the carriage 41. The home sensor 47a is, for example, positioned at a predetermined position on the linear scale 47b and has a light-emitting element and a light-receiving element. In the home sensor 47a, the light-receiving element is positioned so as to sandwich the carriage 41 between itself and the light-emitting element in the front-to-back direction, and receives light from the light-emitting element. When the carriage 41 moves in the left-to-right direction and the light-receiving element detects that the light from the light-emitting element of the home sensor 47a is blocked, the position sensor 47 acquires the home position.

[0081] The linear scale 47b is a long member extending in the left-right direction and has a plurality of light-shielding portions and a plurality of light-transmitting portions (slit portions). In the linear scale 47b, the light-shielding portions and light-transmitting portions are arranged alternately in the left-right direction. The scale sensor 47c has a light-emitting element and a light-receiving element. In the scale sensor 47c, the light-receiving element is positioned so as to sandwich the linear scale 47b between itself and the light-emitting element, and receives light that is emitted from the light-emitting element and passes through the light-transmitting portions of the linear scale 47b. When the carriage 41 moves in the left-right direction and the light-receiving element detects that the light from the light-emitting element of the scale sensor 47c is blocked, the position sensor 47 acquires the distance traveled by the carriage 41. Based on the origin position and the distance traveled, the position sensor 47 detects the left-right position of the carriage 41 and the nozzle 24 of the head 20 mounted thereon, and outputs it to the control device 50. Alternatively, the position sensor 47 may output the origin position and travel distance of the carriage 41 to the control device 50, and the control device 50 may acquire the position of the nozzle 24 based on these values.

[0082] For example, the control device 50 generates image data of the patch chart P shown in Figure 15. In this patch chart P, in the printed patch group P0(D5), the columns to the right of the first first patch P01, the ninth first first patch P01, the seventeenth first patch P01, and the twenty-fifth first patch P01 are arranged downwards in this order. In contrast, in the first image patch group P1(D5), the columns to the left of the first first image patch P1, the ninth first image patch P1, the seventeenth first image patch P1, and the twenty-fifth first image patch P1 are arranged downwards in this order.

[0083] The control device 50 then prints the patch chart P onto the printing medium A based on the image data. For example, while the first head 21 moves between positions k1 and k2 in the left-right direction, the basic color ink ejected from the first nozzle 24a lands on the portion of the printing medium A corresponding to the first patch P01. Also, while the second head 22 moves between positions k1 and k2 in the left-right direction, the spot color ink ejected from the second nozzle 24b lands on the portion of the printing medium A corresponding to the first patch P01. The first patch P01 is printed using this basic color ink and spot color ink.

[0084] Furthermore, as the first head 21 moves between positions k3 and k4 in the left-right direction, the base color ink ejected from the first nozzle 24a lands on the portion of the printing medium A corresponding to the first image patch P1. Also, as the second head 22 moves between positions k3 and k4 in the left-right direction, the spot color ink ejected from the second nozzle 24b lands on the portion of the printing medium A corresponding to the first image patch P1. The first image patch P1 is printed using this base color ink and spot color ink. Positions k1 and k2 are located to the left of positions k3 and k4, and the first patch P01 and the first image patch P1, which are the same color, are printed by ink ejected from the first nozzle 24a and the second nozzle 24b at different positions. As a result, the error in color measurement values ​​due to the position of the patches in the left-right direction can be reduced by using the first patch P01 and the first image patch P1, which are the same color. Since the accuracy of the calibration profile using these colorimetric values ​​is improved, the reproducibility of image C using the calibration profile can be enhanced.

[0085] Furthermore, the arrangement order of the first patch P01 in print patch group P0(D5) and the arrangement order of the first image patch P1 in first image patch group P1(D5) are different from each other. For example, when ink is ejected from the first nozzle 24a of the first head 21 moving to the right, the ink from the first nozzle 24a lands in the first row of first patches P01 sequentially from the first first patch P01 to the eighth first patch P01. In contrast, when ink is ejected from the first nozzle 24a of the first head 21 moving to the right, the ink from the first head 21 lands in the first row of first patches P01 sequentially from the eighth first image patch P1 to the first first image patch P1. Thus, the order in which ink is ejected from the head 20 is different for print patch group P0(D5) and first image patch group P1(D5). Therefore, the color measurement values ​​of the first patch P01 and the first image patch P1, which are the same color, can reduce the error in the color measurement values ​​due to the order in which the ink is ejected from the nozzle 24. As the accuracy of the calibration profile using these color measurement values ​​is improved, the reproducibility of image C using the calibration profile can be improved.

[0086] <Example 7> In the printing apparatus 10 according to Modification 7, as in the above embodiment and Modification 1-3, the print color gamut F patch and the first image color value E1 patch are arranged at different positions determined by random numbers on the same printing medium A.

[0087] Specifically, the control device 50 generates image data of the patch chart P. Here, as described above, the control device 50 acquires the Lab value of the print color gamut F as the print color value of the print patch P0, and also acquires the image color value E included in the first print color gamut F1 from the image color gamut D as the first image color value E1. Then, the control device 50 assigns an ID to the print color value and the first image color value E1.

[0088] Furthermore, the control device 50 divides the area of ​​the patch chart P, which is a single closed region, into multiple sections and assigns IDs to each section in random order. The total number of these sections is greater than or equal to the sum of the print color values ​​and the first image color values ​​E1. The control device 50 then associates the IDs of the sections with the IDs of the print color values ​​and the first image color values ​​E1, and assigns the print patch P0 of the print color values ​​and the first image patch P1 of the first image color values ​​E1 to the corresponding sections.

[0089] Based on the image data in which the color values ​​and placement of the print patch P0 and the first image patch P1 have been determined, the control device 50 prints the patch chart P on a single printing medium A. As a result, the first patch P01 and the first image patch P1, which are the same color, are printed at different positions determined by random numbers on the same printing medium A. This reduces the error in color measurement values ​​due to the patch positions by using the color measurement values ​​of the first patch P01 and the first image patch P1, which are the same color. This improves the accuracy of the calibration profile using these color measurement values, thereby improving the reproducibility of the image C using the calibration profile.

[0090] <Differentiation Example 8> In the printing apparatus 10 according to Modification 8, as in the above embodiment and Modification 1-3, the control device 50 prints a patch of the print color gamut F on a first printing medium A1, which is a printing medium A, and prints a patch of the first image color value E1 on a second printing medium A2, which is a printing medium A but different from the first printing medium A1. The printing position on the first printing medium A1 of the first patch P01, which is a patch with the same color value as the patch of the first image color value E1 in the print color gamut F, and the printing position on the second printing medium A2 of the patch of the first image color value E1 are different from each other in one of the following directions: front-to-back, left-to-right, or both front-to-back and left-to-right.

[0091] Specifically, in the printing operation of step S4 in Figure 4, the control device 50 generates image data of the patch chart P shown in the example in Figure 16. The patch chart P has a plurality of print patches P0 and one or more first image patches P1, and is printed across a plurality of printing media A. The plurality of printing media A include a first printing medium A1 and a second printing medium A2 that are different from each other. For example, the print patches P0 are printed on the first printing medium A1, and the first image patches P1 are printed on the second printing medium A2. Note that all print patches P0 may be printed on a single first printing medium A1, or the print patches P0 may be printed across a plurality of printing media A.

[0092] Print patch P0 includes the first patch P01 of print patch group P0(D5) which is the same color as the first image patch P1 of the first image patch group P1(D5). Print patch group P0(D5) is printed on the first printing medium A1, and the first image patch group P1(D5) is printed on the second printing medium A2. The left-right and front-back positions of the first patch P01 on the first printing medium A1 are different from the left-right and front-back positions of the first image patch P1 of the same color as this first patch P01 on the second printing medium A2. In the example in Figure 16, on the second printing medium A2, the printing position of the first image patch P1 of the first image patch group P1(D5) is behind and to the right of the position corresponding to the printing position of the first patch P01 of print patch group P0(D5) on the first printing medium A1. This corresponding position is the position obtained by applying the left-right and front-back positions of the first patch P01 on the first printing medium A1 to the second printing medium A2. For example, the corresponding position is the position where the first patch P01 of the first printing medium A1 overlaps with the second printing medium A2 when the first printing medium A1 and the second printing medium A2 are superimposed on each other. In this way, the number of colorimetric values ​​per color is greater for the first image color value E1 than for the other color values, and the error due to the position of the colorimetric value on the printing medium A relative to the first image color value E1 can be reduced. As the accuracy of the calibration profile using these colorimetric values ​​is improved, the reproducibility of image C by the calibration profile can be improved.

[0093] <Modification 9> In the modified version 9, the printing apparatus 10, as in modified version 8, causes the control device 50 to print the first patch P01 and the patch of the first image color value E1 using ink ejected from different first nozzles 24a and ink ejected from different second nozzles 24b during the printing operation.

[0094] Specifically, as shown in the example in Figure 17(a), the print patch group P0(D5) is printed on the first printing medium A1. In this print patch group P0(D5), the columns to the right of the first first patch P01, the ninth first first patch P01, the seventeenth first patch P01, and the twenty-fifth first patch P01 are arranged downwards in this order. In contrast, as shown in the example in Figure 17(b), the first image patch group P1(D5) is printed on a second printing medium A2, which is different from the first printing medium A1. In this first image patch group P1(D5), the columns to the right of the first first image patch P1, the ninth first image patch P1, the seventeenth first image patch P1, and the twenty-fifth first image patch P1 are arranged upwards in this order. The first image patch P1 is the same color as the first image patch P01. Similarly, subsequent image patches P1 are the same color as the second and subsequent image patches P01.

[0095] The arrangement order of the first patch P01 in the print patch group P0(D5) and the arrangement order of the first image patch P1 in the first image patch group P1(D5) are different in the front-to-back direction. In contrast, in the first head 21, multiple first nozzles 24a are arranged in the front-to-back direction, and the left first head 21 is positioned behind the right first head 21. For example, the first first patch P01, which is the last row in the print patch group P0(D5), receives ink of the basic color from the left first head 21. In contrast, the first first image patch P1, which is the front row in the first image patch group P1(D5), receives ink of the basic color from the right first head 21.

[0096] In this way, the first patch P01 and the first image patch P1, which are the same color, are hit by base color ink ejected from different first nozzles 24a. Similarly, the first patch P01 and the first image patch P1, which are the same color, are hit by spot color ink ejected from different second nozzles 24b. As a result, the first patch P01 and the first image patch P1, which are the same color, are printed with ink ejected from different nozzles 24. Therefore, the error in the color measurement value by the nozzles 24 can be reduced by the color measurement value of the first patch P01 and the first image patch P1, which are the same color. Since the accuracy of the calibration profile using this color measurement value is improved, the reproducibility of image C by the calibration profile can be improved.

[0097] <Variation 10> In the modified example 10, the printing apparatus 10, as in modified examples 8 and 9, includes a control device 50 equipped with a position sensor 47 that detects the positions of the first nozzle 24a and the second nozzle 24b in the second direction. During the printing operation, the control device 50 causes the first patch P01 and the patch of the first image color value E1 to be printed at different positions from each other using ink ejected from the first nozzle 24a and the second nozzle 24b.

[0098] Specifically, as shown in Figure 1, the control device 50 acquires the left-right position of the nozzle 24 of the head 20 detected by the position sensor 47. As shown in Figure 18(a), the print patch group P0(D5) is printed on the first printing medium A1. In the print patch group P0(D5), for example, the columns to the right of the first first patch P01, the ninth first first patch P01, the seventeenth first patch P01, and the twenty-fifth first patch P01 are arranged downwards in this order. In contrast, as shown in Figure 18(b), the first image patch group P1(D5) is printed on the second printing medium A2. For example, in the first image patch group P1(D5), the columns to the left of the first first image patch P1, the columns to the left of the ninth first image patch P1, the columns to the left of the seventeenth first image patch P1, and the columns to the left of the twenty-fifth first image patch P1 are arranged downwards in this order. The first first image patch P1 is the same color as the first first patch P01. The second and subsequent first image patches P1 are also the same color as the second and subsequent first patches P01, similar to the first first image patch P1.

[0099] For example, as shown in Figure 18(a), while the first head 21 moves between positions k11 and k12 in the left-right direction, the base color ink ejected from the first nozzle 24a lands on the first patch P01 on the first printing medium A1. Furthermore, while the second head 22 moves between positions k11 and k12 in the left-right direction, the spot color ink ejected from the second nozzle 24b lands on the first patch P01 on the first printing medium A1. The first patch P01 is printed on the first printing medium A1 using this base color ink and spot color ink. Also, as shown in Figure 18(b), while the first head 21 moves between positions k13 and k14 in the left-right direction, the base color ink ejected from the first nozzle 24a lands on the first image patch P1 on the second printing medium A2. Furthermore, as the second head 22 moves between positions k13 and k14 in the left-right direction, the special color ink ejected from the second nozzle 24b lands on the first image patch P1 on the second printing medium A2. The first image patch P1 is printed on the second printing medium A2 using this base color ink and the special color ink.

[0100] Thus, the arrangement order of the first patch P01 in the print patch group P0(D5) and the arrangement order of the first image patch P1 in the first image patch group P1(D5) are different in the left-right direction. As a result, for example, ink from the first nozzle 24a of the first head 21 moving to the right will land on the first to eighth first patch P01 in the first row of first patch P01. In contrast, ink from the first nozzle 24a of the first head 21 moving to the right will land on the eighth to first image patch P1 in the first row of first image patch P1. The order in which ink is ejected from the head 20 is different for the print patch group P0(D5) and the first image patch group P1(D5). Therefore, the error in the colorimetric value due to the order in which ink is ejected from the nozzle 24 can be reduced by using the colorimetric values ​​of the first patch P01 and first image patch P1, which are the same color. Since the accuracy of the calibration profile using these colorimetric values ​​is improved, the reproducibility of image C using the calibration profile can be enhanced.

[0101] <Variation 11> In the modified example 11, the printing apparatus 10, as in the above embodiment and modified examples 1-3, includes a first image color value E1 as a representative color value for each of the multiple regions M in the image C. The patch of the first image color value E1 is placed in a different printing medium A from the patch of the printing color gamut F, at a position corresponding to the position of region M in the image C.

[0102] Specifically, the control device 50 acquires, for example, the position of pixel C0 and color values ​​such as RGB values ​​of image C in Figure 19 from the image data, and stores them in association. Based on a predetermined correspondence between RGB values ​​and Lab values, the control device 50 converts the RGB value of pixel C0 to a Lab value, acquires this Lab value as an image color value E, and stores the position of pixel C0 and the image color value E in association. The control device 50 also divides image C into multiple regions M, acquires the image color values ​​E of multiple pixels C0 in each region M based on the correspondence between the position of pixel C0 and the image color value E, acquires a representative color value for each region M, and stores the position of region M and the representative color value in association. Examples of representative color values ​​include the mode, mean, and median of multiple image color values ​​E in region M. The representative color value is the first image color value E1 if it is included in the first printing color gamut F1, and the second image color value E2 if it is included in the second printing color gamut F2. Therefore, the representative color values ​​in multiple regions M include the first image color value E1 and the second image color value E2. If the image color gamut D includes image color values ​​E outside the print color gamut F, the control device 50 may perform a color compression operation on those image color values ​​E before obtaining the representative color values.

[0103] The control device 50 generates image data for the patch chart P and prints the patch chart P onto a printing medium A based on the image data. The patch chart P includes a print patch P0, a first image patch P1 which is a patch of the first image color value E1, and a second image patch P2 which is a patch of the second image color value E2. The print patch P0 is printed on the first printing medium A1, and the first image patch P1 and the second image color value E2 are printed on the second printing medium A2.

[0104] Here, the control device 50 places the first image patch P1 and the second image patch P2 on the patch chart P based on the correspondence between the position in region M and the representative color value. The control device 50 places the first image patch P1 corresponding to the first image color value E1 in the second printing medium A2 at a position corresponding to the position in image C in region M. As a result, for representative color values ​​and first image color values ​​E1 of the same color, the position in image C in region M corresponds to the position of the first image patch P1 of the first image color value E1 in the second printing medium A2. Also, the control device 50 places the second image patch P2 corresponding to the second image color value E2 in the second printing medium A2 at a position corresponding to the position in image C in region M. As a result, for representative color values ​​and second image color values ​​E2 of the same color, the position in image C in region M corresponds to the position of the second image patch P2 of the second image color value E2 in the second printing medium A2.

[0105] For example, the order in which image patches P1 and P2 are arranged horizontally and front-to-back in the second print medium A2 is the same as the order in which regions M are arranged horizontally and front-to-back in the image C printed on the second print medium A2. For example, if regions M1, M2, and M3 are arranged horizontally in order in image C, then in the second print medium A2, the image patch Pm1 of the representative color value of region M1, the image patch Pm2 of the representative color value of region M2, and the image patch Pm3 of the representative color value of region M3 are arranged horizontally in order. If regions M1, M4, and M5 are arranged vertically in order in image C, then in the second print medium A2, the image patch Pm1 of the representative color value of region M1, the image patch Pm4 of the representative color value of region M4, and the image patch Pm5 of the representative color value of region M5 are arranged vertically in order. In other words, the x and y coordinates of region M in image C partially overlap with the x and y coordinates of the first image patch P1 of the first image color value E1 in the second print medium A2. The x and y coordinates of region M in image C partially overlap with the x and y coordinates of the second image patch P2 of the second image color value E2 in the second print medium A2. Furthermore, for example, in directions that intersect each other (e.g., orthogonal), the position of region M in print medium A of the printed image C is the same as the position of the image patches P1 and P2 of the representative color value of that region M in the second print medium A2.

[0106] As a result, the first image patch P1 and the second image patch P2 are printed on the second printing medium A2 as if image C had been mosaicked. In this way, the first image patch P1 and the second image patch P2 are positioned on the second printing medium A2 according to the color values ​​of image C. Therefore, the error in color measurement values ​​due to the positions of the first image patch P1 and the second image patch P2 can be reduced. Since the accuracy of the calibration profile using these color measurement values ​​is improved, the reproducibility of image C using the calibration profile can be improved.

[0107] <Variation 12> The printing apparatus 10 according to Modification 12, as shown in Figure 21, is equipped with a plurality of heads 60, as well as a transfer cylinder 70 and an impression cylinder 71 as transport devices, in the above embodiment and Modifications 1 to 11. The printing apparatus 10 ejects ink from the heads 60 to the transfer cylinder 70, forms an image C on the transfer cylinder 70, and transfers the image C to the printing medium A.

[0108] The head 60 is a line head and has a plurality of nozzles 24. The plurality of nozzles 24 are arranged in a region that is longer than the printing area of ​​the printing medium A in the front-to-back direction. The nozzles 24 open to the lower surface of the head 60, and the lower surface faces the surface of the transfer cylinder 70. For example, the plurality of heads 60 eject different types of ink from each other. The plurality of heads 60 has, for example, four first heads 61 and three second heads 62. The first heads 61 are connected to the first tank 12a by a first flow path 13a and have first nozzles 24a that eject basic color ink. The second heads 62 are connected to the second tank 12b by a second flow path 13b and have second nozzles 24b that eject spot color ink different from the basic color. When a selected spot color ink is stored in the second tank 12b, the spot color ink flows from the second tank 12b into the second flow path 13b, is filled, and is ejected from the second nozzles 24b.

[0109] The transfer cylinder 70 is cylindrical in shape with a central axis 70a extending in the front-to-back direction, and is rotatable around this central axis 70a. Multiple heads 60 are arranged radially from the central axis 70a of the transfer cylinder 70. The impression cylinder 71 is cylindrical in shape with a central axis 71a extending in the front-to-back direction, and is rotatable around this central axis 71a. The transfer cylinder 70 and the impression cylinder 71 are arranged vertically with the printing medium A sandwiched between them.

[0110] The transfer cylinder 70 is equipped with a transfer motor 70b, and the impression cylinder 71 is equipped with an impression cylinder motor 71b. The drive of these transfer motors 70b and impression cylinder motors 71b is controlled by a control device 50 (Figure 3). The transfer cylinder 70 and impression cylinder 71 rotate in opposite directions to transport the printing medium A in the forward and backward directions.

[0111] In the printing operation of this printing apparatus 10, the control device 50 rotates the transfer cylinder 70 and the impression cylinder 71 to transport the printing medium A forward, while simultaneously ejecting basic color ink from the first nozzle 24a of the first head 21 and spot color ink from the second nozzle 24b of the second head 22 onto the transfer cylinder 70. As a result, images such as image C and patch chart P are formed on the transfer cylinder 70. This image moves as the transfer cylinder 70 rotates and is pressed against the printing medium A between the transfer cylinder 70 and the impression cylinder 71, thereby being transferred. In this way, the image is printed onto the printing medium A.

[0112] <Other variations> In the above embodiments and modifications 1 to 11, the printing system may include a plurality of heads 20, platens 11, a plurality of tanks 12, a transport device 30, a scanning device 40, a display device 14, an input device 15, and a control device 50. In this case, the plurality of heads 20, platens 11, a plurality of tanks 12, a transport device 30, and a scanning device 40 may constitute a printing unit, and the display device 14 and the input device 15 may be provided separately from this printing unit. In this case, the display device 14 and the input device 15 may be provided in a computer. Furthermore, the control device 50 may be provided in at least one of the printing unit and the computer.

[0113] In the modified example 12, the printing system may also include a plurality of heads 60, platens 11, a plurality of tanks 12, a transfer cylinder 70, an impression cylinder 71, a display device 14, an input device 15, and a control device 50. In this case as well, the plurality of heads 60, platens 11, a plurality of tanks 12, a transfer cylinder 70, and an impression cylinder 71 may constitute a printing unit, and the display device 14 and the input device 15 may be provided separately from this printing unit. In this case, the display device 14 and the input device 15 may be provided in a computer. The control device 50 may also be provided in at least one of the printing unit and the computer.

[0114] In the embodiments and modifications, the third tank 12c is connected to the third head 23 by the third channel 13c, and the base color ink is supplied to the third head 23, but it is not limited to this. Instead of the base ink, a post-processing ink may be stored in the third tank 12c and supplied from the third tank 12c to the third head 23 by the third channel 13c. For example, the post-processing ink may be a transparent ink that imparts gloss.

[0115] In the embodiments and modifications, the base color ink was supplied to the first head 21 from the first tank 12a via the first channel 13a, the special color ink was supplied to the second head 22 from the second tank 12b via the second channel 13b, and the undercoat color ink was supplied to the third head 23 from the third tank 12c via the third channel 13c, but is not limited thereto. The base color ink, special color ink, and undercoat color ink may all be supplied to the same head 23. Specifically, the base color ink is supplied to the same head 23 from the first tank 12a via the first channel 13a, the special color ink from the second tank 12b via the second channel 13b, and the undercoat color ink from the third tank 12c via the third channel 13c. Furthermore, in this embodiment, the first head 21, the second head 22, and the third head 23 had different nozzle plates 27. However, if the basic color ink, special color ink, and base color ink are supplied to the same head 23, there may be only one nozzle plate 27. This nozzle plate 27 will have a first nozzle row 21a to 21d, a second nozzle row 22a to 22d, and a third nozzle row 23a to 23d. Moreover, if the basic color ink, special color ink, and base color ink are supplied to the same head 23, the number of nozzle rows in the second nozzle row 22a to 22d and the third nozzle row 23a to 23d may be reduced. For example, with respect to the second nozzle rows 22a to 22d and the third nozzle rows 23a to 23d, the second nozzle rows 22b to 22d and the third nozzle rows 23b to 23d may be reduced to just the second nozzle row 22a and the third nozzle row 23a.

[0116] In the embodiment and modified examples, the base color ink was supplied from the first tank 12a to the first head 21 via the first channel 13a, the special color ink was supplied from the second tank 12b to the second head 22 via the second channel 13b, and the undercoat color ink was supplied from the third tank 12c to the third head 23 via the third channel 13c. The first channel 13a, the second channel 13b, and the third channel 13c were rubber tubes and plastic tubes, respectively, and constituted a so-called off-carriage configuration, but are not limited to this. An on-carriage configuration is also possible. In an on-carriage configuration, the carriage 41 comprises the first head 21, the second head 22, the third head 23, the first tank 12a, the second tank 12b, and the third tank 12c, and does not have channels made of rubber tubes or plastic tubes. In the on-carriage configuration, the first channel 13a, the second channel 13b, and the third channel 13c are made of resin, rather than rubber or plastic tubing. For example, if the head 20 is formed from a laminate of multiple resin plates stacked together, the channels 13a, 13b, and 13c may be formed from through holes and depressions provided in the laminate.

[0117] In the embodiments and modifications, the carriage 41 had a first head 21, a second head 22, and a third head 23, but is not limited thereto. The carriage 41 may have the first head 21 and the second head 22 without the third head 23.

[0118] In the embodiment, the carriage 41 had two first heads 21, two second heads 22, and two third heads 23, but is not limited to this. The carriage 41 may have one first head 21, one second head 22, and one third head 23. Alternatively, the carriage 41 may have three or more first heads 21, three or more second heads 22, and three or more third heads 23.

[0119] In modified example 5, during pass processing 3, the base color ink from the first nozzle 24a of the left first head 21, which is positioned after the right first head 21, lands on the first first patch P01, which is the last row in the print patch group P0(D5). In contrast, during pass processing 1, the base color ink from the right first head 21, which is positioned before the left first head 21, lands on the first first image patch P1, which is the front row in the first image patch group P1(D5), but this is not the only option. The transport process may be changed so that the base color ink lands only from the first nozzle 24a of the left first head 21, which is positioned after the right first head 21. Specifically, during pass processing 3, the base color ink lands on the first first patch P01, which is the last row in the print patch group P0(D5), from a nozzle closer to the rear of the first nozzle 24a of the left first head 21. Furthermore, in pass processing 1, the first image patch P1, which is the frontmost row in the first image patch group P1(D5), may be deposited with the basic color ink from the rearmost nozzle of the first nozzle 24a of the left first head 21. Alternatively, the transport process may be changed so that the basic color ink is deposited only from the first nozzle 24a of the right first head 21, which is positioned in front of the left first head 21. Also, for the first patch P01 and the first image patch P1, which are the same color, the special color ink ejected only from the second nozzle 24b of the left second head 22 may be deposited, similar to the basic color, or the special color ink ejected only from the second nozzle 24b of the right second head 22 may be deposited.

[0120] In variation 8, the printing position of the first image patch group P1(D5) on the second printing medium A2 is behind and to the right of the position corresponding to the printing position of the printing patch group P0(D5) on the first printing medium A1. However, it is not limited to this. For example, the printing position of the first image patch group P1(D5) on the second printing medium A2 may be behind and to the left of the position corresponding to the printing position of the printing patch group P0(D5) on the first printing medium A1. Also, the printing position of the first image patch group P1(D5) on the second printing medium A2 may be in front of and to the right of the position corresponding to the printing position of the printing patch group P0(D5) on the first printing medium A1. Also, the printing position of the first image patch group P1(D5) on the second printing medium A2 may be in front of and to the left of the position corresponding to the printing position of the printing patch group P0(D5) on the first printing medium A1.

[0121] Furthermore, all of the above embodiments may be combined with each other, provided that they do not exclude one another. Also, many improvements and other embodiments of the present invention will be apparent to those skilled in the art from the above description. Therefore, the above description should be interpreted as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of its structure and / or function can be substantially modified without departing from the spirit of the invention. [Industrial applicability]

[0122] This invention can be applied to a printing apparatus, a control method thereof, and a computer program that can improve the color proofing of images using special colors. [Explanation of Symbols]

[0123] 10:Printing device 13a: First channel 13b: Second channel 24a: First nozzle 24b: Second nozzle 30: Conveying device 41: Carriage 47: Position sensor 50: Control device

Claims

1. A first nozzle prints an image onto a printing medium based on image data using a predetermined basic color ink, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, Memory unit and, A control device is provided, The memory unit stores the color values ​​of the basic inks, but does not store the color values ​​of the special inks. The control device is Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. Before the second channel is filled with the special color ink, a second acquisition operation is performed to acquire a second printing color gamut, which is the region of the printing color gamut that does not include the special color. A printing operation is performed to print a patch of first image color values, which are color values ​​within the first printable color gamut among the color values ​​included in the image data, onto the printing medium, after the first acquisition operation and after the second channel has been filled with the special color ink. Make it run, The printing apparatus includes a storage unit that stores the color values ​​of the basic color inks and the color values ​​of the spot color inks after the printing operation.

2. The control device is A determination process is performed to determine whether or not the second channel is filled with the special ink. In the printing operation, after the first acquisition operation and after it is determined in the determination process that the second channel is filled with the special color ink, a patch of the second image color value, which is a color value within the second print color gamut among the color values ​​included in the image data, and a patch of the first image color value are printed. The number of patches per color is greater for the first image color value than for the second image color value. The printing apparatus according to claim 1.

3. An input device and It has an interface, If the color value of the special ink is not stored in the storage unit, the control device shall obtain the color value of the special ink via the input device or the interface. The printing apparatus according to claim 1.

4. A first nozzle that prints an image onto a printing medium based on image data using ink of a predetermined basic color, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, A control device is provided, The control device is Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. A determination process to determine whether or not the second channel is filled with the special ink, After the first acquisition operation, and after it is determined in the determination process that the second channel has been filled with the special ink, a printing operation is performed to print a patch of the first image color value, which is a color value within the first print color gamut among the color values ​​included in the image data, onto the printing medium. Before the second channel is filled with the special color ink, a second acquisition operation is performed to acquire a second printing color gamut, which is the region of the printing color gamut that does not include the special color. If the determination process determines that the second channel is filled with the special ink, the printing operation will print the patch of the first image color value instead of the patch of the second image color value, which is a color value within the second printable color gamut among the color values ​​included in the image data. Printing device.

5. A first nozzle that prints an image onto a printing medium based on image data using ink of a predetermined basic color, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, Control device and The system includes a conveying device for conveying the printing medium in a first direction, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. A determination process for determining whether the second channel is filled with the special ink, After the first acquisition operation, and after it is determined in the determination process that the second channel has been filled with the special ink, a printing operation is performed to print a patch of the first image color value, which is a color value within the first print color gamut among the color values ​​included in the image data, onto the printing medium. Execute, If the control device determines in the determination process that the second channel has been filled with the special color ink, it prints the print color gamut patch and the first image color value patch onto a single printing medium during the printing operation. The printing position on the printing medium of a first patch that has the same color value as the patch with the first image color value among the patches of the print color gamut, and the printing position on the printing medium of the patch with the first image color value, are different from each other in any of the following directions: the first direction, the second direction intersecting the first direction, and both the first and second directions. Printing device.

6. The device comprises a carriage for moving the first nozzle and the second nozzle in a second direction intersecting the first direction, The control device, in the printing operation, alternately repeats a pass process in which the carriage moves the first nozzle and the second nozzle while ejecting ink from the first nozzle and the second nozzle onto the printing medium, and a transport process in which the transport device transports the printing medium, and prints the first patch and the patch of the first image color value by different pass processes. The printing apparatus according to claim 5.

7. The device comprises a carriage for moving the first nozzle and the second nozzle in a second direction intersecting the first direction, The first nozzle and the second nozzle are arranged in a row in the first direction, The control device, in the printing operation, prints the first patch and the patch of the first image color value using ink ejected from different first nozzles and ink ejected from different second nozzles. The printing apparatus according to claim 5 or 6.

8. A carriage for moving the first nozzle and the second nozzle in a second direction intersecting the first direction, The system includes a position sensor that detects the positions of the first nozzle and the second nozzle in the second direction, The control device, in the printing operation, prints the first patch and the patch of the first image color value at different positions from each other using ink ejected from the first nozzle and the second nozzle. A printing apparatus according to any one of claims 5 to 7.

9. A first nozzle that prints an image onto a printing medium based on image data using ink of a predetermined basic color, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, A control device is provided, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. A determination process for determining whether the second channel is filled with the special ink, After the first acquisition operation, and after it is determined in the determination process that the second channel has been filled with the special ink, a printing operation is performed to print a patch of the first image color value, which is a color value within the first print color gamut among the color values ​​included in the image data, onto the printing medium. Execute, When the determination process determines that the second channel is filled with the spot color ink, the print color gamut patch and the first image color value patch are arranged at different positions determined by random numbers on the same printing medium. Printing device.

10. A first nozzle that prints an image onto a printing medium based on image data using ink of a predetermined basic color, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, Control device and The system includes a conveying device for conveying the printing medium in a first direction, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. A determination process for determining whether the second channel is filled with the special ink, After the first acquisition operation, and after it is determined in the determination process that the second channel has been filled with the special ink, a printing operation is performed to print a patch of the first image color value, which is a color value within the first print color gamut among the color values ​​included in the image data, onto the printing medium. Execute, If the control device determines in the determination process that the second channel has been filled with the special color ink, in the printing operation, it prints the print color gamut patch on the first printing medium, which is the printing medium, and prints the first image color value patch on the second printing medium, which is the printing medium but is different from the first printing medium. In the print color gamut patch, the print position on the first printing medium of the first patch which is a patch with the same color value as the first image color value patch, and the print position on the second printing medium of the first image color value patch are different from each other in any of the following directions: the first direction, the second direction intersecting the first direction, and both the first and second directions. Printing device.

11. The first nozzle and the second nozzle are arranged in a row in the first direction, The control device, in the printing operation, prints the first patch and the patch of the first image color value using ink ejected from different first nozzles and ink ejected from different second nozzles. The printing apparatus according to claim 10.

12. A carriage for moving the first nozzle and the second nozzle in a second direction intersecting the first direction, The system includes a position sensor that detects the positions of the first nozzle and the second nozzle in the second direction, The control device, in the printing operation, prints the first patch and the patch of the first image color value at different positions from each other using ink ejected from the first nozzle and the second nozzle. The printing apparatus according to claim 10 or 11.

13. A first nozzle that prints an image onto a printing medium based on image data using ink of a predetermined basic color, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, A control device is provided, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. A determination process for determining whether the second channel is filled with the special ink, After the first acquisition operation, and after it is determined in the determination process that the second channel has been filled with the special ink, a printing operation is performed to print a patch of the first image color value, which is a color value within the first print color gamut among the color values ​​included in the image data, onto the printing medium. Execute, The representative color value for each of the multiple regions in the aforementioned image includes the first image color value. When the determination process determines that the second channel is filled with the spot color ink, the patch of the first image color value is placed in a different printing medium than the patch of the printing color gamut, at a position corresponding to the position of the region in the image. Printing device.

14. A first nozzle prints an image onto a printing medium based on image data using a predetermined basic color ink, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, A control method for a printing apparatus comprising a storage unit that stores the color values ​​of the basic inks but does not store the color values ​​of the spot inks, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. Before the second channel is filled with the special color ink, a second acquisition operation is performed to acquire a second printing color gamut, which is the region of the printing color gamut that does not include the special color. A printing operation is performed to print a patch of first image color values, which are color values ​​within the first printable color gamut among the color values ​​included in the image data, onto the printing medium, after the first acquisition operation and after the second channel has been filled with the special color ink. Make it run, A control method for a printing apparatus, comprising storing the color values ​​of the basic color inks and the color values ​​of the spot color inks in the storage unit after the printing operation.

15. A first nozzle prints an image onto a printing medium based on image data using a predetermined basic color ink, A second nozzle prints the image onto the printing medium based on the image data using a special ink different from the basic color, A first channel for supplying the aforementioned basic color ink to the first nozzle, A second channel for supplying the aforementioned special ink to the second nozzle, A printing apparatus comprising a storage unit that stores the color values ​​of the basic inks but does not store the color values ​​of the spot inks, Before the second channel is filled with the special color ink, a first acquisition operation is performed to acquire a first printable color gamut, which is the region of the printable color values ​​of the special color ink and the basic color ink that occupies a predetermined color space, and which includes the special color. Before the second channel is filled with the special color ink, a second acquisition operation is performed to acquire a second printing color gamut, which is the region of the printing color gamut that does not include the special color. A printing operation is performed to print a patch of first image color values, which are color values ​​within the first printable color gamut among the color values ​​included in the image data, onto the printing medium, after the first acquisition operation and after the second channel has been filled with the special color ink. Make it run, A computer program that causes the storage unit to store the color values ​​of the basic inks and the color values ​​of the spot inks after the printing operation.

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