JP2010240935A - Various printing using ink of two or more colors - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily form a great variety of printed matters when printing is performed in inks of two or more colors. <P>SOLUTION: The printing apparatus which performs the printing in the inks of two or more colors includes: a first image forming part which forms a first image on a printing medium by jetting the ink of a first ink group that includes at least one of the inks of two or more colors; and a second image forming part which forms a second image on the printing medium so that at least part of the second image overlaps the first image by jetting the ink of a second ink group that includes at least one of the inks of two or more colors and is an ink group different in color reproduction region from the first ink group. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a technique for performing various printing using a plurality of colors of ink.

  In addition to color inks such as cyan, magenta, and yellow, printing apparatuses that perform printing using white (white) ink are known (see, for example, Patent Document 1). A printing apparatus that performs printing using a plurality of colors of ink including white ink, for example, uses a white ink to perform background processing or grounding of a print medium in order to reproduce a color image without being affected by the ground color of the print medium. It is possible to perform complementary color processing according to the color.

JP 2002-38063 A

  There has been a demand for a technique for easily creating various printed materials when printing is performed using a plurality of colors of ink including white ink.

  Such a problem is not limited to the case where printing is performed using a plurality of colors of ink including white ink, but is a problem common to the case where printing is performed using a plurality of colors of ink.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to make it possible to easily create various printed materials when printing is performed using a plurality of colors of ink.

  In order to solve at least a part of the above problems, the present invention can be realized as the following forms or application examples.

Application Example 1 A printing apparatus that performs printing using a plurality of colors of ink,
A first image forming unit that ejects ink of a first ink group including at least one of the plurality of colors of inks to form a first image on a print medium;
A second image is ejected by ejecting ink of a second ink group that includes at least one of the plurality of colors of ink and has a color reproduction range different from that of the first ink group. And a second image forming unit that forms on the print medium such that at least a part of the second image overlaps the first image.

  In this printing apparatus, a first image group including at least one of a plurality of colors of ink is ejected to form a first image on the print medium, and at least one of the plurality of colors of ink is selected. The second image group is ejected with ink of a second ink group that includes one and has a different color gamut from the first ink group, and at least part of the second image is the first image. Therefore, it is possible to easily create various printed materials including a plurality of images having different color gamuts.

[Application Example 2] The printing apparatus according to Application Example 1, further including:
The formation of the first image by the first image forming unit and the formation of the second image by the second image forming unit are performed in parallel during at least a part of the printing period. A printing apparatus comprising a control unit that controls the first image forming unit and the second image forming unit.

  In this printing apparatus, the formation of the first image by the first image forming unit and the formation of the second image by the second image forming unit are performed in parallel during at least a part of the printing period. Thus, it is possible to efficiently and easily create various printed materials including a plurality of images having different color gamuts.

[Application Example 3] The printing apparatus according to Application Example 1 or Application Example 2, further comprising:
A printing apparatus comprising: a head having a first nozzle group as the first image forming unit and a second nozzle group as the second image forming unit.

  In this printing apparatus, the first image can be formed on the print medium by the first nozzle group of the head, and the second image can be formed on the print medium by the second nozzle group of the head. Therefore, various printed materials including a plurality of images having different color gamuts can be easily created.

[Application Example 4] The printing apparatus according to any one of Application Example 1 to Application Example 3,
The plurality of colors of ink includes white ink;
The printing apparatus, wherein the first ink group does not include the white ink, and the second ink group includes the white ink.

  In this printing apparatus, the first image group that does not include white ink can be ejected to form the first image on the print medium, and the second ink group that includes white ink can be ejected. Since the second image can be formed on the print medium so that at least a part of the second image overlaps the first image, various printed materials including a plurality of images having different color gamuts using white ink can be easily obtained. Can be created.

Application Example 5 The printing apparatus according to Application Example 4, further comprising:
A color designating unit that obtains a density value and a color value in a predetermined color system for the color of the second image;
The printing apparatus, wherein the second image forming unit forms the second image based on the acquired value.

  In this printing apparatus, the density value and the color value in a predetermined color system are acquired and acquired for the color of the second image formed by ejecting the ink of the second ink group including the white ink. Since the second image is formed based on the value, the color of the second image formed by ejecting the ink of the second ink group including the white ink can be specified accurately and easily.

[Application Example 6] The printing apparatus according to Application Example 5,
The color designation unit is a printing apparatus that acquires at least one of the density value and a color value in the predetermined color system based on a color measurement result of an object.

  In this printing apparatus, since at least one of the density value and the color value in a predetermined color system is acquired based on the color measurement result of the object, the ink is formed by ejecting ink of the second ink group including white ink. The color of the second image to be processed can be specified more accurately and more easily.

[Application Example 7] The printing apparatus according to Application Example 6,
The printing apparatus according to claim 1, wherein the color designation unit acquires at least one of the density value and a color value in the predetermined color system based on a color measurement result on a white background and a color measurement result on a black background.

  In this printing apparatus, since at least one of the density value and the colorimetric value in the predetermined color system is acquired based on the colorimetric result on the white background and the colorimetric result on the black background, for example, the colorimetric result on the white background Is obtained by ejecting ink of the second ink group including white ink by acquiring color values in a predetermined color system based on the color and acquiring density values based on the colorimetric result on a black background. The color of the second image can be specified more accurately and more easily.

[Application Example 8] The printing apparatus according to any one of Application Example 5 to Application Example 7,
The printing apparatus, wherein the predetermined color system is one of an L ^* a ^* b ^* color system and an L ^* u ^* v ^* color system.

  The present invention can be realized in various modes. For example, a printing method and apparatus, a printing control method and apparatus, a printing system, and a computer program for realizing the functions of these method, apparatus, and system It can be realized in the form of a recording medium recording the computer program, a data signal including the computer program and embodied in a carrier wave, and the like.

1 is an explanatory diagram schematically showing a configuration of a printing system in a first embodiment of the present invention. FIG. It is explanatory drawing which shows the structure of PC200 roughly. FIG. 2 is an explanatory diagram schematically illustrating a configuration of a printer. 2 is a block diagram functionally showing the configuration of a PC 200. FIG. FIG. 2 is a block diagram functionally showing the configuration of a printer. 3 is a flowchart showing a flow of printing processing in the printing system 10 of the present embodiment. It is explanatory drawing which shows an example of print image PI, color image data Cdata, and white image data WIdata. It is explanatory drawing which shows the printing order of a color image and a toning white image. 4 is a flowchart illustrating a flow of processing by a CPU 210 that executes a printer driver 300. It is a flowchart which shows the flow of a toning white designation | designated process. It is explanatory drawing which shows an example of UI window for toning white designation | designated. It is explanatory drawing which shows the color measurement method of real print RP. It is a flowchart which shows the flow of the color conversion process ink color separation process halftone process for a toned white image. It is explanatory drawing which shows partially an example of the look-up table LUTw for toned white images. It is a flowchart which shows the flow of the color conversion process ink color separation process halftone process for color images. It is explanatory drawing which shows partially an example of the look-up table for color images LUTc. It is a flowchart which shows the flow of command creation processing. It is explanatory drawing which shows an example of the command produced by command creation processing. It is explanatory drawing which shows an example of the content of the ink code table | surface ICT. 3 is a flowchart showing a flow of processing by the printer. It is explanatory drawing which shows the detailed structure of a raster buffer and a head buffer. 4 is an explanatory diagram illustrating a configuration of a print head 144 of the printer 100. FIG. It is explanatory drawing which shows the concept of the white color to which white is adjusted. It is explanatory drawing which shows an example of the color reproduction area (gamut) of a color image and a toned white image. It is a flowchart which shows the flow of the color conversion process for the toned white image in a 2nd Example, an ink color separation process, and a halftone process. It is a block diagram which shows functionally the structure of PC200b of 3rd Example. It is a block diagram which shows functionally the structure of PC200c of 4th Example. It is a block diagram which shows functionally the structure of the printer 100d of 5th Example. It is a flowchart which shows the flow of the command creation process in 5th Example. 14 is a flowchart illustrating a flow of processing by a printer 100d according to a fifth embodiment. It is explanatory drawing which shows the storage method to the head buffer 142 of raster data.

Next, embodiments of the present invention will be described in the following order based on examples.
A. First embodiment:
A-1. Printing system configuration:
A-2. Printing process:
B. Second embodiment:
C. Third embodiment:
D. Fourth embodiment:
E. Example 5:
F. Variation:

A. First embodiment:
A-1. Printing system configuration:
FIG. 1 is an explanatory diagram schematically showing the configuration of a printing system according to a first embodiment of the present invention. The printing system 10 according to the present exemplary embodiment includes a printer 100 and a personal computer (PC) 200. The printer 100 is an ink jet color printer that prints an image by ejecting ink to form ink dots on a printing medium (for example, printing paper or transparent film). The PC 200 functions as a print control apparatus that supplies printing data to the printer 100 and controls the printing operation by the printer 100. The printer 100 and the PC 200 are connected to be able to communicate information by wire or wireless. Specifically, in this embodiment, the printer 100 and the PC 200 are connected to each other by a USB cable. FIG. 1 shows an actual printed matter (hereinafter also referred to as “real print RP”) created by printing with a gravure printing machine, for example.

  The printer 100 of this embodiment includes cyan (C), magenta (M), yellow (Y), black (K), light cyan (Lc), light magenta (Lm), and white (W). The printer performs printing using a total of seven colors of ink. The printing system 10 according to the present embodiment realizes a printing process in which a color image and a toned white image are formed in parallel on a transparent film as a printing medium. The transparent film on which the color image and the toned white image are formed is used as, for example, a product packaging film.

  In the present specification, adjusting white by mixing white ink with another color ink is referred to as “white toning”. Further, white (adjusted white) generated by white toning is called “toned white”, and an image composed of toned white is called “toned white image”.

  FIG. 2 is an explanatory diagram schematically showing the configuration of the PC 200. The PC 200 includes a CPU 210, a ROM 220, a RAM 230, a USB interface (USB I / F) 240, a network interface (N / W I / F) 250, a display interface (display I / F) 260, and a serial interface ( Serial I / F) 270, hard disk drive (HDD) 280, and CD drive 290 are included. Each component of the PC 200 is connected to each other via a bus.

  A USB interface compatible colorimeter CM is connected to the USB interface 240 of the PC 200. A monitor MON as a display device is connected to the display interface 260. The serial interface 270 is connected to a keyboard KB and a mouse MOU as input devices. Note that the configuration of the PC 200 illustrated in FIG. 2 is merely an example, and some of the components of the PC 200 may be omitted or further components may be added to the PC 200.

  FIG. 3 is an explanatory diagram schematically showing the configuration of the printer 100. The printer 100 includes a CPU 110, a ROM 120, a RAM 130, a head controller 140, a print head 144, a carriage controller (CR controller) 150, a carriage motor (CR motor) 152, and a print medium feed controller (PF controller) 160. A print medium feed motor (PF motor) 162, a USB interface (USB I / F) 170, a network interface (N / W I / F) 180, and a monitor 190 as a display unit. Each component of the printer 100 is connected to each other via a bus.

  The CPU 110 of the printer 100 functions as a control unit that controls the operation of the entire printer 100 by executing a computer program stored in the ROM 120. The print head 144 of the printer 100 is mounted on a carriage (not shown). The carriage controller 150 controls the carriage motor 152 to reciprocate the carriage in a predetermined direction. Thereby, the main scanning in which the print head 144 reciprocates along a predetermined direction (main scanning direction) of the print medium is realized. The print medium feed controller 160 controls the print medium feed motor 162 to perform sub-scanning for transporting the print medium in a direction (sub-scanning direction) orthogonal to the main scanning direction. The print head 144 has a nozzle group (see FIG. 22) that ejects ink, and the head controller 140 controls ink ejection from the nozzle group by the print head 144 in conjunction with main scanning and sub scanning. Thereby, formation of an image (printing of an image) on the print medium is realized.

  FIG. 4 is a block diagram functionally showing the configuration of the PC 200. The ROM 220 (FIG. 2) of the PC 200 stores an application program AP and a printer driver 300 as computer programs executed by the CPU 210. The application program AP is a program for generating, editing, and the like of an image (hereinafter also referred to as “print image PI”) to be printed on a transparent film as a print medium. The CPU 210 executes generation and editing of the print image PI by executing the application program AP.

  In addition, the CPU 210 that executes the application program AP outputs color image data Cdata, white image data WIdata, and print order designation information SS to the printer driver 300 in accordance with a print execution instruction from the user. The contents of each data will be described in detail in “A-2. Printing process”.

  The printer driver 300 (FIG. 4) generates print data (print command) based on the image data, and controls the printer 100 (FIG. 1) based on the print data to perform print processing of the print image PI. It is a program. The CPU 210 (FIG. 2) implements print control of the print image PI by the printer 100 by executing the printer driver 300.

  As shown in FIG. 4, the printer driver 300 includes a color image ink color separation processing module 310, a color image halftone processing module 320, a toned white designation module 330, and a toned white image color conversion module. 340, a toned white image ink color separation processing module 350, a toned white image halftone processing module 360, and a command creation module 370. The toned white designation module 330 includes a UI control module 332. The HDD 280 (FIG. 2) of the PC 200 includes a color image lookup table (LUT) LUTc, a color image halftone (HT) resource HTc, a toned white image lookup table (LUT) LUTw, A toned white image halftone (HT) resource HTw and an ink code table ICT are stored, and the printer driver 300 and each module execute processing with reference to these pieces of information. The function of each module and the contents of each information will be described in detail in “A-2. Printing process”.

  FIG. 5 is a block diagram functionally showing the configuration of the printer 100. A command processing module 112 is stored in the ROM 120 (FIG. 3) of the printer 100 as a computer program executed by the CPU 110. As will be described later, the CPU 110 executes a command processing module 112 to realize processing of a command received from the PC 200. In addition, the RAM 130 (FIG. 3) of the printer 100 has a raster buffer 132. The raster buffer 132 includes two areas of a color image raster buffer 132c and a toned white image raster buffer 132w. The color image raster buffer 132c corresponds to the first region of the buffer in the present invention, and the toned white image raster buffer 132w corresponds to the first region of the buffer in the present invention. The head controller 140 (FIG. 3) of the printer 100 has a head buffer 142. The head buffer 142 includes an upstream head buffer 142u and a downstream head buffer 142l. The upstream head buffer 142u corresponds to the upstream region of the head buffer in the present invention, and the downstream head buffer 142l corresponds to the downstream region of the head buffer in the present invention. The functions and detailed configurations of these programs and buffers will be described in detail in “A-2. Printing Process”.

A-2. Printing process:
FIG. 6 is a flowchart showing the flow of printing processing in the printing system 10 of the present embodiment. The printing process of the present embodiment is a process of forming a color image and a toned white image in parallel on a transparent film as a printing medium, and creating a printed matter in which the color image and the toned white image are formed. is there.

  In step S110 (FIG. 6), the CPU 210 (FIG. 2) that executes the application program AP (FIG. 4) receives a print execution instruction from the user. In response to receiving the print execution instruction, the CPU 210 outputs the color image data Cdata, the white image data WIdata, and the print order designation information SS to the printer driver 300 (FIG. 4). The color image data Cdata is data for specifying a color image in the print image PI, the white image data WIdata is data for specifying a white area Aw (described later) in the print image PI, and the print order designation information SS is color This is data for specifying the printing order (described later) of the color image and the toned white image at the portion where the image and the toned white image overlap.

  FIG. 7 is an explanatory diagram illustrating an example of the print image PI, color image data Cdata, and white image data WIdata. FIG. 7A shows an example of the print image PI. The print image PI includes a color image Ic (an image “ABC” and an image “abc... P” in the drawing). The print image PI includes a white area Aw and a non-white area An. The white area Aw is an area where a toned white image is formed, and the non-white area An is an area where no toned white image is formed. In the example shown in FIG. 7A, at least a part of the white area Aw of the print image PI overlaps with the color image Ic.

  FIG. 7B conceptually shows the color image data Cdata. In the present embodiment, the color image data Cdata specifies the color of each pixel of the print image PI with an 8-bit C value, M value, Y value, and K value when attention is paid only to the color image Ic of the print image PI. It is data to be. The color image data Cdata is data specifying the color of the color image Ic for pixels corresponding to the color image Ic of the print image PI, and data indicating that no color image is formed for the remaining pixels (for example, C , M, Y, K = 0).

  FIG. 7C conceptually shows the white image data WIdata. In the present embodiment, the white image data WIdata is data that specifies the color of each pixel of the print image PI with an 8-bit W value when the color image Ic is excluded from the print image PI. However, the value that the W value can take is either 0 or 255. The white image data WIdata is data (for example, W = 255) indicating that a toned white image is formed for the pixels corresponding to the white area Aw of the print image PI, and the remaining pixels (corresponding to the non-white area An). Pixel) is data (for example, W = 0) indicating that a toned white image is not formed. The white image data WIdata may be 2-bit data.

  FIG. 8 is an explanatory diagram showing the printing order of a color image and a toned white image. FIG. 8A shows a printing order in which the toned white image Iw is formed on the transparent film as the print medium PM and the color image Ic is formed on the toned white image Iw. In this specification, this printing order is referred to as “white-color printing” or “WC printing”. In the WC printing shown in FIG. 8A, the observer observes the printed matter from above the figure (see the arrow in the figure).

  FIG. 8B shows a printing order in which the color image Ic is formed on the transparent film as the print medium PM, and the toned white image Iw is formed on the color image Ic. In this specification, this printing order is referred to as “color-white printing” or “C-W printing”. In the C-W printing shown in FIG. 8B, the observer observes the printed matter from the lower side of the figure (see the arrow in the figure).

  The user selects whether to perform W-C printing or C-W printing according to the usage of the printed matter. The CPU 210 that executes the application program AP generates printing order designation information SS that specifies the printing order selected by the user, and outputs it to the printer driver 300 (FIG. 4).

  In step S120 of the printing process (FIG. 6), processing by the CPU 210 that executes the printer driver 300 (FIG. 4) is executed. FIG. 9 is a flowchart showing the flow of processing by the CPU 210 that executes the printer driver 300. In step S210, the CPU 210 receives the color image data Cdata, white image data WIdata, and printing order designation information SS output from the application program AP (see FIG. 4).

  In step S220 (FIG. 9), the toned white designation module 330 (FIG. 4) executes a toned white designation process. The toned white designation process is a process for designating the color of the toned white image corresponding to the white area Aw (see FIG. 7A) of the print image PI. FIG. 10 is a flowchart showing the flow of the toned white designation process. In step S310, the UI control module 332 (FIG. 4) of the toned white designation module 330 displays a toned white designation UI window on the monitor MON (FIG. 2) of the PC 200.

  FIG. 11 is an explanatory diagram showing an example of a UI window for specifying a toned white. As shown in FIG. 11A, the toned white designation UI window W1 of this embodiment includes a sample image display area Sa, two slider bars S11 and Sl2, an ab plane display area Pl, and a print order designation. A column Se1, a value input box Bo1, a measurement button B1, and an OK button B2 are included.

  In the toned white designation UI window W1 shown in FIG. 11A, the sample image display area Sa is an area for displaying a designated toned white sample image. The sample image display area Sa is divided into right and left, and the left side is a toned white area (white background area) in a white background (White Backing), and the right side is a toned white in a black background (Black Backing). (Black background area) showing The outermost peripheral area of the sample image display area Sa is an area (background color area) indicating a background color (white or black), and an area inside the background color area is an area indicating a toned white (white image area). It is. The image displayed in the white image area in the black background area corresponds to the first sample image in the present invention, and the image displayed in the white image area in the white background area corresponds to the second sample image in the present invention. To do. Further, a color image (an image “A” in the figure) is displayed near the center of the sample image display area Sa so as to extend over both the white background area and the black background area. The color and shape of this color image can be arbitrarily set.

In the toned white designation UI window W1, a value input box Bo1 includes a colorimetric value (L ^* value (hereinafter also simply referred to as “L value”), a ^* value (hereinafter referred to as “L ^* a”) in the L ^* a ^* b ^* color system. simply expressed as "a value"), b ^* value (hereinafter, a portion for specifying the toned white by simply inputting also represent)) and T value as "b-value". The L value is a value indicating the brightness of the toned white, and correlates with the amount of black (K) ink when the toned white image is printed. The a value and the b value are values representing the chromaticity along the red-green axis and the yellow-blue axis of the toned white, and correlate with the amount of color ink when the toned white image is printed. The T value is a value indicating the density and correlates with the ink amount per unit area when the toned white image is printed. That is, the T value correlates with the transparency of the background color.

  In the toned white designation UI window W1, the slider bars Sl1, Sl2 and the ab plane display area Pl are also portions for designating the toned white by inputting the Lab value and the T value.

  In the toned white designation UI window W1, the print order designation column Se1 is a portion for indicating the designation of the print order described above. The print order is set in the application program AP, and print order designation information SS for specifying the print order is output from the application program AP to the printer driver 300 (see FIG. 4). The printing order designation field Se1 indicates whether the printing order specified by the printing order designation information SS is WC printing (W-C Print) or C-W printing (C-W Print). It is. In the toned white designation UI window W1, it is possible to designate a change in the printing order (designation of a new printing order) indicated in the printing order designation column Se1.

  When the toned white designation UI window W1 is first displayed, the display state of the value input box Bo1, the sample image display area Sa, and the like is a display state corresponding to the default toned white. Yes. For example, the default state is a display state corresponding to the Lab value and the T value preset as the white ink color of the printer 100.

  The UI control module 332 (FIG. 4) monitors the presence / absence of an operation by the user via the keyboard KB or the mouse MOU (FIG. 2) when the toned white designation UI window W1 is displayed (FIG. 10). Step S320). When it is determined that there is an operation (step S320: Yes) and the operation is neither the OK button B2 nor the measurement button B1 (step S330: No, S340: No), the UI control module 332 sets a value corresponding to the operation. Obtain (step S360), display the obtained value in the value input box Bo1 or the like (step S370), and update the display of the sample image display area Sa (step S380).

  For example, when the user selects the value input box Bo1 and inputs a value via the keyboard KB (FIG. 2), the input value is displayed in the value input box Bo1 and the color of the sample image display area Sa is the input value. Is changed to the color specified by (toned white). When the user changes the a value or the b value in the value input box Bo1, the color of the color (toned white) of the white image area of the sample image display area Sa is changed. When the user changes the L value of the value input box Bo1, the brightness of the color of the white image area of the sample image display area Sa is changed. When the user changes the T value of the value input box Bo1, the transparency of the background color is changed, so that the brightness of the color of the white image area in the black background area of the sample image display area Sa is changed. The color of the white image area in the white background area is not changed. Therefore, the color change according to the change of the T value (density value) can be easily confirmed by comparing the black background area and the white background area of the sample image display area Sa, and the user can adjust the toned white color. Can be specified more accurately and more easily.

  For example, when the user operates the mouse MOU (FIG. 2) to change the position of the slider bar S11, the L value corresponding to the position is acquired, and the color of the sample image display area Sa is specified by the acquired value. Changed to color. Similarly, when the user operates the mouse MOU to change the position of the slider bar S12, a T value corresponding to the position is acquired, and the color of the sample image display area Sa is changed. When the user operates the mouse MOU to change the position of the designated point (indicated by x in the figure) of the ab plane display area Pl, the a value and b value corresponding to the position of x are acquired, and the sample image display area The color of Sa is changed.

  The value input box Bo1, the slider bars Sl1, Sl2, and the ab plane display area Pl are interlocked. That is, when the value is changed in the value input box Bo1, the positions of the slider bars S11 and S12 and the x position in the ab plane display area Pl are changed. Similarly, when the position of the slider bars Sl1, Sl2 or the position of x in the ab plane display area Pl is changed, the changed designated value is displayed in the value input box Bo1.

  In this embodiment, the toned white can be designated based on the color measurement result of the real print RP (see FIG. 1). By specifying the toned white based on the color measurement result of the real print RP, it is possible to realize a printing process that faithfully reproduces the color of the white portion of the real print RP.

  FIG. 12 is an explanatory diagram showing a color measurement method of the real print RP. The real print RP is a printed matter in which an image of the white portion Pw and an image of the color portion Pc are formed on the print medium PM. As shown in FIG. 12A, in the color measurement, an arbitrary point of the white portion Pw of the real print RP is set as the measurement point MP, and the color (Lab value and T value) of the measurement point MP is set to the colorimeter CM. (FIG. 2). Color measurement methods include a white background color measurement performed by placing a real print RP on a white background Bw, and a black background color measurement performed by placing a real print RP on a black background Bb. As shown in FIG. 12B, the colorimetric value (L value) may differ between the white background colorimetry and the black background colorimetry depending on the density of the white portion Pw of the real print RP. In the present embodiment, the white background colorimetry is performed to acquire the Lab value, and the black background colorimetry is performed to acquire the T value. Thereby, it is possible to specify the toned white more accurately and easily.

  When it is determined in step S320 in FIG. 10 that an operation has been performed (step S320: Yes), and it is determined that the operation is not the OK button B2 (step S330: No) but the measurement button B1 (step S340: Yes). ), The UI control module 332 (FIG. 4) displays the colorimetric UI window W2 shown in FIG. 11B on the monitor MON (FIG. 2) of the PC 200 (step S350).

  The color measurement UI window W2 (FIG. 11B) is a UI window for designating toned white by color measurement of the real print RP. The colorimetric UI window W2 includes a background selection area Se2, a colorimetric value display box Bo2, a measurement button B3, and an OK button B4. The background selection area Se2 is a part for selecting whether to perform white background color measurement or black background color measurement. The user selects a colorimetry method in the background selection area Se2 and selects the measurement button B3, and executes colorimetry using the selected method. For the color measurement, both the white background color measurement and the black background color measurement may be executed in order, or only one of the white background color measurement and the black background color measurement may be executed. When the color measurement is completed, a value (at least one of the Lab value and the T value) based on the color measurement result is acquired (step S360 in FIG. 10) and displayed in the color measurement value display box Bo2 (step S370). When the user selects the OK button B4, the toned white designation UI window W1 (FIG. 11A) is displayed again. At this time, the display of the sample image display area Sa, the value input box Bo1, and the like of the toned white designation UI window W1 is changed to a display based on the color measurement result (step S380). In addition, after the color measurement is executed, the user can correct the values (Lab value and T value) acquired based on the color measurement result in the toned white designation UI window W1.

  When it is determined in step S320 in FIG. 10 that an operation has been performed (step S320: Yes) and the operation is determined to be an OK button B2 (step S330: Yes), the UI control module 332 (FIG. 4) The color specified by the Lab value and the T value acquired and displayed at that time is set as the color of the toned white image, and the Lab value and the T value are stored (step S390). With the above processing, the user can specify the color of the toned white image accurately and easily. In particular, the color of the toned white image can be designated more accurately and more easily by designating the Lab and T values of the toned white based on the colorimetry result obtained by the colorimeter CM. Further, in this embodiment, the toned white can be designated by the Lab value and the T value, so that the color value including the density of the toned white image can be designated accurately. In the toned white designation UI window W1 of the present embodiment, the designated color is displayed in the sample image display area Sa, so that the user can easily designate the color while confirming the displayed color. it can.

  The saved Lab value and T value are combined with the white image data WIdata (see FIG. 7C). That is, in the white image data WIdata, the Lab value and the T value are associated with a pixel to which data (W = 255) indicating that a toned white image is to be formed is assigned. In this specification, the white image data WIdata in which the Lab value and the T value are associated is also referred to as toned white image data.

  In step S230 in the process by the printer driver 300 (FIG. 9), the printer driver 300 executes a color conversion process for a toned white image, an ink color separation process, and a halftone process. FIG. 13 is a flowchart showing the flow of color conversion processing, ink color separation processing, and halftone processing for a toned white image. In step S410, the toned white image color conversion module 340 (FIG. 4) color-converts the Lab value stored in step S390 of the toned white designation process (FIG. 10) into a CMYK value. The color conversion is executed with reference to the toned white image lookup table LUTw (FIG. 4).

  FIG. 14 is an explanatory diagram partially showing an example of the toned white image lookup table LUTw. FIG. 14A shows a toned white image look-up table LUTw1 that is referred to during color conversion from Lab values to CMYK values. As shown in FIG. 14A, the toned white image look-up table LUTw1 defines a correspondence relationship between Lab values and CMYK values set in advance. In the toned white image look-up table LUTw1, the CMYK gradation values are defined as values in the range of 0 to 100. The toned white image color conversion module 340 refers to the toned white image look-up table LUTw1 and converts the Lab value to the CMYK value.

  In step S420 (FIG. 13), the toned white image ink color separation processing module 350 (FIG. 4) is stored in step S390 of the CMYK value determined in step S410 and the toned white designation process (FIG. 10). Ink color separation processing is performed for converting the combination with the T value into a gradation value for each ink color. As described above, the printer 100 according to this embodiment includes cyan (C), magenta (M), yellow (Y), black (K), light cyan (Lc), and light magenta (Lm). Printing is performed using white (W) and a total of seven colors of ink. Therefore, in the ink color separation process, the combination of the CMYK value and the T value is converted into the gradation values of the seven ink colors. The ink color separation process is also executed with reference to the toned white image lookup table LUTw (FIG. 4). FIG. 14B shows a toned white image look-up table LUTw2 that is referred to when a combination of CMYK values and T values is converted into gradation values for each ink color. As shown in FIG. 14B, the toned white image look-up table LUTw2 defines the correspondence between preset combinations of CMYK values and T values and the gradation values of ink colors. Yes. In the toned white image lookup table LUTw2, the gradation value of the ink color is defined as a value in the range of 0 to 255. The toned white image ink color separation processing module 350 refers to the toned white image look-up table LUTw2 and converts the combination of the CMYK value and the T value into a gradation value for each ink color.

  In this embodiment, as shown in FIG. 14B, in this embodiment, white tone (mixing white ink with another color ink to adjust white color), yellow ink among six colors except white is used. Four colors of ink (Y), black (K), light cyan (Lc), and light magenta (Lm) are used, and two colors of ink of cyan (C) and magenta (M) are used. Not. That is, for the white tone, dark ink is not used among the two types of inks of light color ink and dark color ink for the same hue.

  In step S430 (FIG. 13), the toned white image ink color separation processing module 350 (FIG. 4) extracts one pixel data in the toned white image data. In step S440, the toned white image ink color separation processing module 350 forms the toned white image with the extracted pixel value being a value (zero) indicating that the toned white image is not formed. It is determined which value is the indicated value (255). When it is determined that the pixel value is 255 (step S440: No), the toned white image ink color separation processing module 350 stores the gradation value for each ink color determined in step S420. (Step S450). On the other hand, when it is determined that the value of the pixel is 0 (zero) (step S440: Yes), the process of step S450 is skipped.

  The processing from step S430 to S450 in FIG. 13 is repeatedly executed until the processing for all the pixels of the toned white image data is completed (see step S460). When the processing for all the pixels has been completed (step S460: Yes), the toned white image halftone processing module 360 (FIG. 4) extracts the gradation value for each ink color (step S470), Binarization processing (halftone processing) is performed with reference to the dither pattern for each ink color (step S480). The binarization process is executed with reference to a preset toned white image halftone resource HTw (FIG. 4). The toned white image halftone resource HTw may be set with emphasis on dot filling in the toned white image. The binarization process is repeatedly executed until the process for all ink colors is completed (see step S490). Further, the processing from step S470 to S490 is repeatedly executed until the processing for all the pixels is completed (see step S492).

  The color conversion processing, ink color separation processing, and halftone processing for the toned white image shown in FIG. 13 define ON / OFF of each ink color dot of each pixel when forming the toned white image. Toned white image dot data is generated.

  In step S240 in the processing by the printer driver 300 (FIG. 9), the printer driver 300 executes color image color conversion processing, ink color separation processing, and halftone processing. FIG. 15 is a flowchart showing the flow of color conversion processing for color image, ink color separation processing, and halftone processing. In step S510, the color image ink color separation processing module 310 (FIG. 4) takes out data of one pixel in the color image data. In step S520, the color image ink color separation processing module 310 performs ink color separation processing for converting the extracted data of one pixel (CMYK value) into gradation values for each ink color. As described above, the printer 100 according to this embodiment includes cyan (C), magenta (M), yellow (Y), black (K), light cyan (Lc), and light magenta (Lm). Printing is performed using white (W) and a total of seven colors of ink. Therefore, in the ink color separation process, the CMYK values are converted into the gradation values of the seven ink colors. The ink color separation process is executed with reference to the color image lookup table LUTc (FIG. 4).

  FIG. 16 is an explanatory diagram partially showing an example of the color image lookup table LUTc. As shown in FIG. 16, in the color image look-up table LUTc, a correspondence relationship between preset CMYK values and respective tone values of ink colors is defined. In the color image look-up table LUTc, the CMYK gradation values are defined as values in the range of 0 to 100, and the ink color gradation values are defined as values in the range of 0 to 255. Has been. The color image ink color separation processing module 310 refers to the color image look-up table LUTc and converts the CMYK values into gradation values for each ink color. As shown in FIG. 16, in this embodiment, six color inks except white are used to form a color image, and no white ink is used.

  The processing in steps S510 and S520 in FIG. 15 is repeatedly executed until the processing for all the pixels of the color image data is completed (see step S530). When the processing for all the pixels is completed (step S530: Yes), the color image halftone processing module 320 (FIG. 4) extracts the gradation value for each ink color (step S540), and the ink color Binarization processing (halftone processing) is performed with reference to the dither pattern every time (step S550). The binarization process is executed with reference to a color image halftone resource HTc (FIG. 4) set in advance. The color image halftone resource HTc may be set with emphasis on suppression of graininess. The binarization process is repeatedly executed until the process for all ink colors is completed (see step S560). Further, the processing from step S540 to S560 is repeatedly executed until the processing for all the pixels is completed (see step S570).

  Color image dots that define ON / OFF of each ink color dot of each pixel when forming a color image by color conversion processing, ink color separation processing, and halftone processing shown in FIG. Data is generated.

  In step S250 in the processing by the printer driver 300 (FIG. 9), the command creation module 370 (FIG. 4) of the printer driver 300 performs command creation processing. FIG. 17 is a flowchart showing the flow of command creation processing.

  In step S610 of the command creation process (FIG. 17), the command creation module 370 (FIG. 4) creates a print order designation command based on the print order designation information SS output from the application program AP. FIG. 18 is an explanatory diagram showing an example of a command created by command creation processing. FIG. 18A shows an example of the print order designation command. As shown in FIG. 18A, the print order designation command includes an identifier indicating the head of the command, an identifier indicating the print order designation command, a command length (2 bytes), and a print order designation. It is out. In the printing order designation, for example, the value “0” represents C-W printing (the printing order in which the color image Ic is first formed and the toned white image Iw is formed on the color image Ic), and the value “1”. "Represents WC printing (printing order in which the toned white image Iw is first formed and the color image Ic is formed on the toned white image Iw). The command creation module 370 identifies the print order with reference to the print order designation information SS, and creates a print order designation command that designates the identified print order.

  In step S620 (FIG. 17), the command creation module 370 (FIG. 4) receives the color image dot data received from the color image halftone processing module 320 and the toning received from the toned white image halftone processing module 360. A vertical position designation command is created based on the white image dot data. The vertical position designation command is a command for designating the start position of the image along the vertical direction (Y direction). The vertical position designation command is created as a command common to all inks.

  Next, the command creation module 370 (FIG. 4) creates a raster command corresponding to the color image through the processing from step S630 (FIG. 17) to S670. In step S630, the command creation module 370 creates a horizontal position designation command for the selected one ink color based on the color image dot data. The horizontal position designation command is a command for designating the start position of an image along the horizontal direction (X direction) for one ink color when forming a color image. The command creation module 370 refers to color image dot data for one ink color, sets an appropriate image start position, and creates a horizontal position designation command.

  In step S640 (FIG. 17), the command creation module 370 (FIG. 4) extracts one raster worth of dot data for one selected ink color from the color image dot data. In step S650, the command creation module 370 searches the ink code with reference to the ink code table ICT. FIG. 19 is an explanatory diagram showing an example of the contents of the ink code table ICT. As shown in FIG. 19, in this embodiment, a unique ink abbreviation and ink code are assigned to each ink color. Further, in this embodiment, two different ink abbreviations and ink codes for color image and toned white image are assigned to one ink color. That is, the ink abbreviation and the ink code uniquely correspond to the combination of each of the plurality of ink colors and each of the color image and the toned white image. For example, for cyan, ink abbreviation “C” and ink code “01H” are assigned for color images, and ink abbreviation “WC” and ink code “81H” are assigned for toned white images. Similarly, for white, the ink abbreviation “IW” and the ink code “40H” are assigned for color images, and the ink abbreviation “W” and the ink code “C0H” are assigned for toned white images. . In this step (S650), the command creation module 370 searches for an ink code for a color image in the ink code table ICT.

  In step S660 (FIG. 17), the command creation module 370 (FIG. 4) creates a raster command based on the extracted dot data for one raster and the retrieved ink code. FIG. 18B shows an example of a raster command. As shown in FIG. 18B, the raster command includes an identifier indicating the head of the command, an identifier indicating the raster command, an ink code, an identifier indicating the presence / absence of data compression, and the number of bits per pixel. X direction length (2 bytes), Y direction length (2 bytes), and raster data (dot data). The raster command corresponds to the printing command in the present invention, and the raster data (dot data) included in the raster command corresponds to the printing data in the present invention.

  The processing from step S630 to S660 of the command creation processing (FIG. 17) is repeatedly executed until all the ink colors used for forming the color image are completed. That is, when there is an ink color that is not yet a target of processing (step S670: No), one ink color that is not a target of processing is selected, and steps S630 to S660 are selected for the selected ink color. Processing is executed. When the processing for all inks is completed (step S670: Yes), the creation of raster commands corresponding to each of the ink colors used to form a color image is completed for one raster.

  Next, the command creation module 370 (FIG. 4) creates a raster command corresponding to the toned white image through the processing from step S680 (FIG. 17) to S720. In step S680, the command creation module 370 creates a horizontal position designation command for the selected one ink color based on the toned white image dot data. The horizontal position designation command is a command for designating the start position of the image along the horizontal direction (X direction) for one ink color when forming the toned white image. The command creation module 370 refers to the toned white image dot data for one ink color, sets an appropriate image start position, and creates a horizontal position designation command.

  In step S690 (FIG. 17), the command creation module 370 (FIG. 4) extracts dot data for one raster for one selected ink color from the toned white image dot data. In step S700, the command creation module 370 searches for an ink code with reference to the ink code table ICT. The command creation module 370 searches the ink code for the toned white image in the ink code table ICT (FIG. 19).

  In step S710 (FIG. 17), the command creation module 370 (FIG. 4) creates a raster command (see FIG. 18B) based on the extracted dot data for one raster and the retrieved ink code. . The processing from step S680 to step S710 of the command creation processing is repeatedly executed until all the ink colors used for forming the toned white image are completed. That is, when there is an ink color that has not yet been processed (step S720: No), one ink color that has not been processed is selected, and steps S680 to S710 are performed for the selected ink color. Processing is executed. When the processing for all inks is completed (step S720: Yes), the creation of raster commands corresponding to each of the ink colors used for forming the toned white image is completed for one raster.

  The processing from step S620 to step S720 of the command creation processing (FIG. 17) is repeatedly executed until all rasters of the print image PI are completed. That is, when there is a raster that has not yet been processed (step S730: No), a raster that has not been processed (the raster that is one lower than the previous raster to be processed) is selected and selected. The process from step S620 to S720 is executed for the raster. When processing for all rasters is completed (step S730: Yes), creation of commands corresponding to each of the ink colors used for forming the color image and the toned white image is completed for all rasters.

  In step S260 in the process by the printer driver 300 (FIG. 9), the printer driver 300 transmits the print order designation command, the vertical position designation command, the horizontal position designation command, and the raster command created in step S250 to the printer 100. . Thus, the processing by the printer driver 300 is completed.

  In step S130 of the printing process (FIG. 6), the process by the printer 100 is executed. FIG. 20 is a flowchart showing the flow of processing by the printer 100. In step S810, the CPU 110 (FIG. 3) executing the command processing module 112 (FIG. 5) of the printer 100 receives a command transmitted from the printer driver 300 of the PC 200. CPU 110 determines the type of command received (step S820), and executes processing according to the type of command. If the received command is a printing order designation command, the CPU 110 stores information indicating the printing order designated by the printing order designation command in the RAM 130 (step S830), and the received command is a horizontal position designation command. In this case, the horizontal print start position X is updated (step S840).

  When the received command is a raster command, the CPU 110 (FIG. 3) that executes the command processing module 112 (FIG. 5) converts the raster data (dot data) included in the raster command into a raster buffer for each ink code. 132 (FIG. 5) (step S850). FIG. 21 is an explanatory diagram showing the detailed configuration of the raster buffer and the head buffer. The upper part of FIG. 21 shows a raster buffer 132c for a color image, and the middle part shows a raster buffer 132w for a toned white image. As shown in FIG. 21, the raster buffer 132 is assigned a region for each ink code (see FIG. 19). That is, the color image raster buffer 132c is configured as a set of regions corresponding to the color image ink codes, and the toned white image raster buffer 132w is also the toned white image ink code. It is comprised as a set of the area | region corresponding to each. The size in the X direction of each area of the raster buffer 132 corresponds to the image size, and the size in the Y direction is one half or more of the height of the print head 144. The raster buffer 132 has a raster buffer pointer in the Y direction that indicates how far raster data has been received.

  The lower part of FIG. 21 shows the head buffer 142 (FIG. 5). As shown in FIG. 21, the head buffer 142 is allocated with regions for each of seven ink colors. In other words, the head buffer 142 includes an area for cyan (for C and WC), an area for magenta (for M and WM), an area for yellow (for Y and WY), and an area for black (for K and WK). ), A light cyan (Lc, WLc) area, a light magenta (Lm, WLm) area, and a white (IW, W) area. The size in the X direction of each area of the head buffer 142 corresponds to the scanning distance of the carriage, and the size in the Y direction corresponds to the number of nozzles constituting the nozzle row 146 of the print head 144. Each region of the head buffer 142 for each ink color is divided into an upstream portion 142u and a downstream portion 142l.

  FIG. 22 is an explanatory diagram showing the configuration of the print head 144 of the printer 100. As shown in FIGS. 22A and 22B, the print head 144 is provided with nozzle rows 146 corresponding to the seven ink colors. The nozzle row 146 is formed so as to extend along the Y direction (print medium feeding direction). Further, as shown in FIG. 22C, each nozzle row 146 is composed of 32 nozzle groups arranged along the print medium feeding direction. Among the nozzle groups constituting the nozzle row 146, the nozzle group (from the first nozzle (nozzle 1) to the 16th nozzle (nozzle 16)) located in the upstream half along the print medium feeding direction is the upstream nozzle group. The nozzle group (from the 17th nozzle (nozzle 17) to the 32nd nozzle (nozzle 32)) located in the downstream half along the print medium feeding direction is called a downstream nozzle group.

  As shown in FIG. 22A, during WC printing, a toned white image is formed using the upstream nozzle group of each nozzle row 146 of the print head 144, and the downstream nozzle group is used. A color image is formed. Further, as shown in FIG. 22B, during C-W printing, a color image is formed using the upstream nozzle group of each nozzle row 146 of the print head 144, and the downstream nozzle group is used. A toned white image is formed. During WC printing, the upstream nozzle group of each nozzle row 146 of the print head 144 corresponds to the second nozzle group in the present invention, and the downstream nozzle group corresponds to the first nozzle group in the present invention. To do. On the other hand, during CW printing, the upstream nozzle group of each nozzle row 146 of the print head 144 corresponds to the first nozzle group in the present invention, and the downstream nozzle group corresponds to the second nozzle group in the present invention. Equivalent to.

  As shown in FIG. 21, the upstream head buffer 142u is a head buffer 142 corresponding to an upstream portion (upstream nozzle group) along the print medium feeding direction of the print head 144, and the downstream head buffer 142l is The head buffer 142 corresponds to a downstream portion (downstream nozzle group) along the print medium feeding direction of the print head 144.

  In step S850 of FIG. 20, the CPU 110 (FIG. 3) refers to the ink code included in the received raster command, and stores the raster data at the position specified by the raster buffer pointer of the raster buffer 132 corresponding to the ink code. To do. Therefore, the CPU 110 can distribute raster data to an appropriate raster buffer 132 without being aware of whether the raster command is for a color image or a toned white image.

  When the received command is a vertical position designation command, the CPU 110 (FIG. 3) that executes the command processing module 112 (FIG. 5) updates the print start position Y in the vertical direction (step S860). Next, the CPU 110 determines whether or not the raster buffer 132 corresponding to half the height of the print head 144 (FIG. 5) is full (that is, raster data is stored) (step S870). ). If it is determined that it is not yet full (step S870: No), the CPU 110 updates the raster buffer pointer of the raster buffer 132 (step S880).

  When the processing described above is repeated and raster data is stored in the raster buffer 132 corresponding to half of the height of the print head 144, the raster buffer corresponding to half of the height of the print head 144 is stored. It is determined that 132 is full (step S870: Yes). At this time, the CPU 110 (FIG. 3) determines whether the printing order is C-W printing or WC printing based on the information indicating the printing order stored in the RAM 130 (step S880). If it is determined that the printing order is C-W printing (step S880: Yes), the CPU 110 transfers raster data from the color image raster buffer 132c to the upstream head buffer 142u (FIG. 5), and Raster data is transferred from the toned white image raster buffer 132w to the downstream head buffer 142l (FIG. 5) (step S890). In FIG. 21, when the printing order is C-W printing, raster data is transferred from the color image raster buffer 132c to the upstream head buffer 142u, and the downstream head buffer from the toned white image raster buffer 132w. It shows how raster data is transferred to 142l. As a result, color image formation is performed using the upstream nozzle group of each nozzle row 146 of the print head 144, and toned white image formation is performed using the downstream nozzle group (FIG. 22B). )) Will be ready. Since the printing position on the physical paper is different between the upstream nozzle group and the downstream nozzle group, when the raster data is transferred from the raster buffer 132, the difference in the printing position between the upstream nozzle group and the downstream nozzle group is considered. Then, the transfer start data position on the raster buffer is determined.

  On the other hand, when it is determined that the printing order is WC printing (step S880: No), the CPU 110 transfers raster data from the color image raster buffer 132c to the downstream head buffer 142l (FIG. 5). At the same time, the raster data is transferred from the toned white image raster buffer 132w to the upstream head buffer 142u (step S900). Thereby, the toned white image is formed using the upstream nozzle group of each nozzle row 146 of the print head 144, and the color image is formed using the downstream nozzle group (see FIG. 22A). )) Will be ready.

  Next, the CPU 110 (FIG. 3) controls the print medium feed controller 160 and the print medium feed motor 162 to transport (sub-scan) the print medium PM to the head position Y (step S910) and the CR controller 150. Then, the CR motor 152 is controlled to move the print head 144 to the print start position X (step S920), and further, the main scan is performed to perform printing for the height of the print head 144 (step S930). At this time, in WC printing (see FIG. 22A), the formation of the toned white image by the upstream nozzle group (see FIG. 22C) of the nozzle row 146 of the print head 144 and the color image by the downstream nozzle group. Are formed in parallel. In C-W printing (see FIG. 22B), the color image formation by the upstream nozzle group of the nozzle row 146 of the print head 144 and the toned white image formation by the downstream nozzle group are executed in parallel. The

  Next, the CPU 110 (FIG. 3) clears the raster buffer pointer of the raster buffer 132 (step S940), determines whether or not the printing process for the entire print image PI has been completed (step S950), and the printing process is performed. The processes from step S810 to S940 are repeatedly executed until it is determined that the process has been completed. If it is determined that the printing process has been completed, the printing process (FIG. 6) ends.

  As described above, in the printing system 10 according to the present exemplary embodiment, it is possible to execute a printing process that forms a color image and a toned white image on the print medium PM using a plurality of colors including white. During the printing process by the printing system 10, each of the seven nozzle arrays 146 corresponding to the seven ink colors provided in the print head 144 of the printer 100 is divided into an upstream nozzle group and a downstream nozzle group (see FIG. 22 (c)). In WC printing (see FIG. 22A), a toned white image is formed by ejecting ink from the upstream nozzle group, and C-W printing (see FIG. 22B). In this case, a toned white image is formed by ejecting ink from the downstream nozzle group. Therefore, in both cases of WC printing and CW printing, a toned white image can be formed using white and at least one color ink other than white. Therefore, in the printing system 10 of the present embodiment, when executing a printing process for forming a color image and a toned white image on the print medium PM using a plurality of colors including white, the toned white image The color can be a desired color.

FIG. 23 is an explanatory diagram showing the concept of white toning for adjusting white. FIG. 23A shows an example of the position P1 of the white ink color of the printer 100 in the a ^* -b ^* plane. FIG. 23B further shows the target white position P2 and the printer. An example of a color position P3 in which a predetermined amount of yellow ink is mixed with 100 white inks is shown. As shown in FIG. 23B, for example, by mixing yellow ink with white ink of the printer 100, the color of the toned white image can be brought close to the target white. Further, for example, by mixing a predetermined amount of light magenta and yellow ink, the color of the toned white image can be made closer to the target white. Thus, when forming the toned white image, the color of the toned white image can be set to a desired color by using the white ink and at least one color ink other than white.

FIG. 24 is an explanatory diagram illustrating an example of a color reproduction area (gamut) of a color image and a toned white image. FIG. 24A shows the gamut Gc of the color image viewed from the −b ^* direction and the gamut Gw of the toned white image, and FIG. 24B shows the color image viewed from the + a ^* direction. Gamut Gc and gamut Gw of the toned white image are shown. As described above, in this embodiment, one of the upstream nozzle group and the downstream nozzle group of the nozzle array 146 of the print head 144 (first image forming unit) is used for forming a color image (first image). Used. Further, for the formation of a color image, among the seven colors of ink, six colors of ink (first ink group) excluding white are used, and no white ink is used. On the other hand, to form the toned white image (second image), the other (second image forming unit) of the upstream nozzle group and the downstream nozzle group of the nozzle row 146 of the print head 144 is used. In addition, for the formation of the toned white image, five colors of ink (second ink group) of white, yellow, black, light cyan, and light magenta among the seven colors of ink are used, and cyan and magenta 2 Color ink is not used. Since the color gamut of the first ink group and the color gamut of the second ink group are different from each other, the gamut Gc (first color gamut) of the color image and the gamut Gw (first gamut of the toned white image) 2) is different from each other. In the printing process by the printing system 10 of the present embodiment, two images (color image and toned white image) having different color gamuts can be formed on the print medium PM, and a plurality of images having different color gamuts can be formed. It is possible to easily create various printed materials including the images. Further, in the printing process performed by the printing system 10 according to the present exemplary embodiment, the formation of the color image and the formation of the toned white image are performed in parallel during at least a part of the printing period. It is possible to efficiently and easily create various printed materials including the images.

  In the printing process by the printing system 10 according to the present embodiment, the toned white image is formed using one of the upstream nozzle group and the downstream nozzle group in both the WC printing and the CW printing. Since a color image is formed using the other, the color of the toned white image is set to a desired color even when at least a part of the toned white image overlaps the color image on the print medium. It can be.

  In the printing process by the printing system 10 according to the present embodiment, in either the WC printing or the C-W printing, one of the upstream nozzle group and the downstream nozzle group is set in the same main scanning (same pass). The formation of the toned white image used and the formation of the color image using the other can be executed in parallel. Therefore, instead of first forming one whole of the toned white image and the color image on the print medium and then forming the other whole on the print medium, the color image and the color image are formed on the print medium by one printing process. A toned white image can be formed, and the toned white image can have a desired color.

  In the printing process performed by the printing system 10 according to the present exemplary embodiment, the printer 100 receives the printing order designation command (FIG. 18A) for designating the printing order from the PC 200, and the printing order for forming the color image first is designated. In this case, the upstream nozzle group is set as the nozzle group used for forming the color image and the downstream nozzle group is set as the nozzle group used for forming the toned white image, and the toned white image is formed first. When the order is designated, the upstream nozzle group is set as the nozzle group used for forming the toned white image, and the downstream nozzle group is set as the nozzle group used for forming the color image. Therefore, in the printing process by the printing system 10 according to the present embodiment, the color of the toned white image can be set to a desired color regardless of the CW printing or the WC printing. (Refer to FIG. 8).

  Further, in the printing system 10 of the present embodiment, the ink code included in the raster command (FIG. 18B) as the printing command includes seven colors of ink, a color image, and a toned white image, respectively. Are set so as to uniquely correspond to the combination. Therefore, the CPU 110 of the printer 100 is conscious of whether the raster command is for a color image or a toned white image, and uses a nozzle group (upstream) for forming a color image based on a raster command including an ink code corresponding to the color image. Control the nozzle group (downstream nozzle group or upstream nozzle group) used to form the toned white image based on the raster command including the ink code corresponding to the toned white image. Can do.

  In the printing system 10 of the present embodiment, the raster buffer 132 of the printer 100 includes a color image area 132c and a toned white image area 132w (see FIG. 5). Therefore, the CPU 110 of the printer 100 stores the raster data included in the raster command including the ink code corresponding to the color image in the color buffer area 132c, and includes the ink code corresponding to the toned white image. By storing the raster data included in the raster command in the toned white image area 132w, the nozzle group used for forming the color image and the nozzle group used for forming the toned white image can be controlled.

  Further, in the printing process by the printing system 10 of this embodiment, for the formation of the toned white image, among the six colors of ink other than white, yellow (Y), black (K), light cyan (Lc), Light magenta (Lm) and four colors of ink are used, and cyan (C) and magenta (M) are not used. That is, for the formation of the toned white image, dark ink is not used among the two types of inks of light color ink and dark color ink for the same hue. Therefore, in the printing process according to the present exemplary embodiment, it is possible to suppress deterioration in image quality (increase in graininess) in the toned white image while setting the color of the toned white image to a desired color. In the printing process of this embodiment, since the black (K) ink is used to form the toned white image, the brightness of the toned white image can be adjusted, and the selectable range of the color of the toned white image is possible. Can be extended.

  Further, in the printing process by the printing system 10 according to the present embodiment, the toned white (the color of the toned white image) can be designated in the toned white designation UI window W1 (FIG. 11). It is possible to accurately and easily specify the color of the toned white image when the color image and the toned white image are printed using the color ink. In particular, in the printing system 10 according to the present embodiment, the colors (Lab value and T value) can be specified based on the color measurement result by the colorimeter CM, so that the color of the toned white image can be more accurately and easily. Can be specified. Further, in the printing system 10 of the present embodiment, the toned white can be designated by the Lab value and the T value, and therefore the color value including the density of the toned white image can be designated accurately. Further, in the printing system 10 of the present embodiment, since the designated color is displayed in the sample image display area Sa of the toned white designation UI window W1, the user can easily change the color while confirming the displayed color. Can be specified.

B. Second embodiment:
In the first embodiment, the color of the white area Aw (see FIG. 7A) of the print image PI is one color specified by the toned white designation process (step S220 in FIG. 9), and the toned white image Is formed as an image of a specified color. On the other hand, in the second embodiment, the color of the white area Aw is allowed to be different for each part. That is, in the second embodiment, in the toned white designation process, it is possible to designate a color (Lab value and T value) for each partial area obtained by dividing the white area Aw of the print image PI into a plurality of partial areas. .

  FIG. 25 is a flowchart showing the flow of color conversion processing, ink color separation processing, and halftone processing for a toned white image in the second embodiment. In FIG. 25, steps having the same contents as those in the first embodiment shown in FIG. 13 are denoted by common step numbers. In the first embodiment, since the colors (Lab value and T value) of each pixel corresponding to the white area Aw of the toned white image data are all the same, color conversion from the Lab value to the CMYK value (step of FIG. 13). S410) and conversion from CMYK, T values to gradation values for each ink color (step S420 in FIG. 13) are executed in common for all pixels. On the other hand, in the second embodiment, since the color of the pixel corresponding to the area Aw of the toned white image data may be different for each pixel, one pixel of the toned white image data is extracted (see FIG. 25). Step S402) color conversion from Lab value to CMYK value (step S410 in FIG. 25) and conversion from CMYK, T value to gradation value for each ink color (step S420 in FIG. 25) for each extracted pixel. Done. These processes are repeated until all the pixels are completed (see step S422 in FIG. 25). The processing after step S470 in FIG. 25 (halftone processing) is the same as in the first embodiment shown in FIG.

  As described above, also in the second embodiment, a color image and a toned white image can be formed on the print medium PM, and the toned white image can have a desired color. Furthermore, in the second embodiment, a plurality of types of toned white images having different colors can be formed on the print medium PM, so that a wider variety of printed matter can be created.

C. Third embodiment:
FIG. 26 is a block diagram functionally showing the configuration of the PC 200b of the third embodiment. The PC 200b of the third embodiment is different from the PC 200 of the first embodiment shown in FIG. 4 in that the application program APb includes the UI control module UM and the printer driver 300b does not include the toned white designation module 330. Is different. That is, in the third embodiment, the toned white designation process (step S220 in FIG. 9) is executed not by the printer driver 300b but by the application program APb. The contents of the toned white designation process in the third embodiment are the same as the contents of the toned white designation process shown in the first embodiment.

  In the printing process of the third embodiment, after the toned white designation process is executed by the application program APb, when the user issues a print execution instruction, the color image data Cdata, the toned white image data WITdata, and the print order designation information are displayed. SS is output to the printer driver 300b, and processing by the printer driver 300b is started. The contents of the color image data Cdata and the printing order designation information SS are the same as in the first embodiment. The toned white image data WITdata includes the Lab value and T specified by the toned white designation processing in the white image data WIdata (data specifying the white area Aw (see FIG. 7) in the print image PI) of the first embodiment. Data associated with values.

  In the processing by the printer driver 300b, the color conversion module 340b for the toned white image of the printer driver 300b that has received the toned white image data WITdata performs color conversion of the Lab value defined by the toned white image data WITdata to a CMYK value. . This color conversion is executed in the same manner as in the first embodiment (step S230 in FIG. 9). Subsequent processing contents are the same as those in the first embodiment (step S240 in FIG. 9).

  As described above, also in the third embodiment, a color image and a toned white image can be formed on the print medium PM, and the color of the toned white image can be set to a desired color.

D. Fourth embodiment:
FIG. 27 is a block diagram functionally showing the configuration of the PC 200c of the fourth embodiment. The PC 200c according to the fourth embodiment differs from the third embodiment shown in FIG. 26 in the data output from the application program APc to the printer driver 300c. That is, in the fourth embodiment, white image data WIdata and toned white data WTdata are output instead of the toned white image data WITdata in the third embodiment. The contents of the white image data WIdata are the same as in the first embodiment. The toned white data WTdata is data indicating the Lab value and the T value specified by the toned white specifying process executed by the UI control module UM of the application program APc.

  In the printing process of the fourth embodiment, after the toned white designation process is executed by the application program APc, when the user issues a print execution instruction, the color image data Cdata, the white image data WIdata, and the toned white data WTdata The printing order designation information SS is output to the printer driver 300c, and processing by the printer driver 300c is started.

  In the processing by the printer driver 300c, the color conversion module 340c for the toned white image of the printer driver 300c that has received the toned white data WTdata converts the Lab value specified by the toned white data WTdata into a CMYK value, and performs color conversion. The converted data is output to the toned white image ink color separation processing module 350c. This color conversion is executed in the same manner as in the first embodiment (step S230 in FIG. 9). The toned white image ink color separation processing module 350c also receives the white image data WIdata, and performs ink color separation processing using the color-converted data and the white image data WIdata (step of FIG. 9). S230). Subsequent processing contents are the same as those in the first embodiment (step S240 in FIG. 9).

  As described above, also in the fourth embodiment, a color image and a toned white image can be formed on the print medium PM, and the toned white image can have a desired color.

E. Example 5:
The fifth embodiment is different from the first embodiment in which the printer driver 300 executes a process of converting raster data (dot data) into a data transfer method to the print head 144. Is different. FIG. 28 is a block diagram functionally illustrating the configuration of the printer 100d according to the fifth embodiment. The printer 100d according to the fifth embodiment is different from the printer 100 according to the first embodiment shown in FIG. 5 in that the raster buffer 132 is not provided. Other configurations of the printer 100d are the same as those of the printer 100 of the first embodiment. The other configuration of the printing system 10 (FIG. 1) in the fifth embodiment, that is, the configuration of the PC 200 is the same as that of the first embodiment.

  FIG. 29 is a flowchart showing the flow of command creation processing in the fifth embodiment. In FIG. 29, steps having the same contents as the command creation processing steps of the first embodiment shown in FIG. 17 are given common step numbers. In the command creation process of the fifth embodiment, the command creation module 370 (FIG. 4) performs a process of extracting dot data for one raster for one ink color selected from the color image dot data (step S640). The process is repeatedly executed until the extraction of data corresponding to half the height of the head 144 is completed (see step S642). In step S640, raster dot data corresponding to the nozzle pitch of the nozzle row 146 of the print head 144 is extracted. That is, when the nozzle pitch and the Y-direction print resolution are the same, dot data of successive rasters are sequentially extracted. However, if the nozzle pitch is twice the Y-direction print resolution, one raster is obtained. Flying dot data is sequentially extracted.

  When the extraction of half the height of the print head 144 is completed (step S642: Yes), the ink code is searched (step S650), and a raster command for a color image is created (step S660). . That is, in the fifth embodiment, a raster command including raster data that is half the height of the print head 144 is created.

  Similarly, a raster command including raster data for half the height of the print head 144 is created for the toned white image raster command (steps S690 and S692 in FIG. 29). When the command creation process ends, the created command is transmitted to the printer 100d as in the first embodiment (step S260 in FIG. 9).

  FIG. 30 is a flowchart illustrating a process flow of the printer 100d according to the fifth embodiment. In FIG. 30, steps having the same contents as the steps of the processing by the printer of the first embodiment shown in FIG. 20 are given common step numbers. Command reception processing (step S810 in FIG. 30), command type determination processing (step S820), processing when it is determined that the command is a printing order designation command (step S830), in the printer 100d of the fifth embodiment, The content of the process (step S840) when it is determined that the command is a horizontal position designation command is the same as in the first embodiment.

  If it is determined that the command is a raster command, the ink code included in the raster command is for a color image (step S851: Yes), and the printing order designated in the printing order designation command is C-W printing. If this is the case (step S852: No), the raster image for color image included in the raster command is stored in the upstream head buffer 142u (step S855). On the other hand, if the ink code is for a color image (step S851: Yes) and the printing order designated in the printing order designation command is WC printing (step S852: Yes), it is included in the raster command. Color image raster data is stored in the downstream head buffer 142l (step S856).

  FIG. 31 is an explanatory diagram showing a method for storing raster data in the head buffer 142. FIG. 31A shows a method of storing raster data during C-W printing. As shown in FIG. 31A, during C-W printing, color image raster data is stored in the upstream head buffer 142u, and during WC printing, color image raster data is stored in the downstream head buffer 142l. Stored in

  If the ink code is for a toned white image (step S851: No) and the printing order designated in the printing order designation command is C-W printing (step S853: No), the raster command includes The raster data for the toned white image included is stored in the downstream head buffer 142l (step S857) (see FIG. 31A). On the other hand, if the ink code is for a toned white image (step S851: No) and the print order specified in the print order specifying command is WC printing (step S853: Yes), the raster command The raster data for the toned white image included is stored in the upstream head buffer 142u (step S858) (see FIG. 31B).

  If it is determined that the command is a vertical position designation command, the print start position Y in the vertical direction is updated (step S860), and whether or not the head buffer 142 is full (that is, raster data is stored). Is determined (step S872). If it is determined that it is not yet full (step S872: No), the process returns to the command reception process again (step S810).

  If it is determined that the head buffer 142 is full (step S872: Yes), the print medium PM is transported to the head position Y (sub-scanning is performed) (step S910), and the print head 144 reaches the print start position X. The main scanning is performed and printing for the height of the print head 144 is executed (step S930).

  As described above, in the fifth embodiment, raster data is stored in the head buffer 142 based on the raster command output from the printer driver 300 and received by the printer 100d, and the raster stored in the head buffer 142 is stored. Printing is executed based on the data. Also in the fifth embodiment, a color image and a toned white image can be formed on the print medium PM, and the toned white image can have a desired color.

F. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

F1. Modification 1:
The configuration of the printing system 10 in each of the above embodiments is merely an example, and the configuration of the printing system 10 can be variously modified. For example, in each of the above embodiments, the printer 100 is a printer that performs printing using seven colors of ink of cyan, magenta, yellow, black, light cyan, light magenta, and white. Any printer that performs printing using a plurality of colors of ink may be used. For example, the printer 100 may be a printer that performs printing using inks of five colors of cyan, magenta, yellow, black, and white.

  In each of the above embodiments, six color inks except white are used for forming a color image, and no white ink is used. However, the ink color used for forming a color image is the use of the printer 100. It can be arbitrarily set according to possible ink colors. For example, white ink may be used to form a color image.

  Further, in each of the above embodiments, five color inks of white, yellow, black, light cyan, and light magenta are used to form a toned white image, and two colors of cyan and magenta are not used. However, the ink color used for forming the toned white image only needs to include at least one color other than white and white, and can be arbitrarily set according to the ink color that can be used by the printer 100. For example, only four colors of white, yellow, light cyan, and light magenta may be used to form a toned white image, or white, yellow, black, light cyan, light magenta, cyan, and magenta. Color ink may be used.

  In each of the above embodiments, the printer 100 is a printer that performs printing while reciprocating (main scanning) the carriage on which the print head 144 is mounted. However, the present invention does not involve a reciprocating movement of the carriage. It can also be applied to print processing by a printer.

  In each of the embodiments described above, the printer driver 300 is included in the PC 200, and the printer 100 receives a command from the printer driver 300 of the PC 200 and executes printing (see FIG. 4). It has the same function as the printer driver 300 including the white / white designation module 330 and the UI control module 332, and the printer 100 receives the color image data Cdata, white image data WIdata, and print order designation information SS from the application program AP of the PC 200. It is good also as what performs printing. Alternatively, the printer 100 may further have the same function as the application program AP, and the printer 100 may generate the color image data Cdata, the white image data WIdata, the print order designation information SS, and perform print processing.

  Further, the contents of the toned white image look-up table LUTw (FIG. 14) and the color image look-up table LUTc (FIG. 16) in the above-described embodiments are merely examples, and these contents are, for example, the ink used by the printer 100. It is experimentally set in advance according to the composition. Further, these contents can be variously modified according to the contents of data (used color space) output from the application program AP and the used ink color of the printer 100. Similarly, the contents of color conversion processing and ink color separation processing using these tables can be variously modified.

  In each of the above embodiments, the halftone processing with reference to the dither pattern is performed by the color image halftone processing module 320 or the toned white image halftone processing module 360 (FIG. 4). Halftone processing by another method such as a method may be performed. If the printer 100 can form dots of a plurality of sizes for each ink color, the dot ON / OFF and the dot size are not binarized for determining dot ON / OFF by halftone processing. Multi-value conversion may be performed.

  Further, the configuration of the printing order designation command and the raster command (FIG. 18) and the contents of the ink code table ICT (FIG. 19) in each of the above embodiments are merely examples and can be variously modified. In each of the above embodiments, the ink code uniquely corresponds to the combination of each of the plurality of ink colors and each of the color image and the toned white image. However, the ink code is not necessarily like this. Need not be set to However, if the ink code is set in this way, the CPU 110 of the printer 100 processes the command according to the ink code included in the raster command without being conscious of whether the raster command is for a color image or a toned white image. be able to.

  In each of the above embodiments, a part of the configuration realized by hardware may be replaced by software, and conversely, a part of the configuration realized by software may be replaced by hardware. Also good.

  In addition, when part or all of the functions of the present invention are realized by software, the software (computer program) can be provided in a form stored in a computer-readable recording medium. In the present invention, the “computer-readable recording medium” is not limited to a portable recording medium such as a flexible disk or a CD-ROM, but an internal storage device in a computer such as various RAMs and ROMs, a hard disk, etc. It also includes an external storage device fixed to the computer.

F2. Modification 2:
In each of the above embodiments, a printing process in which a color image and a toned white image are formed in parallel on a transparent film as the printing medium PM, and a printed matter in which the color image and the toned white image are formed is created. As described above, the print medium PM used for the printing process is not limited to a transparent film, and any medium such as a translucent film, paper, or cloth can be selected. When a transparent film is used as the print medium PM, the color image Ic can be formed as it is even in C-W printing (FIG. 8B).

  Further, the printer 100 in each of the above embodiments can execute a printing process for forming only a color image (including a color image formed using white ink). In this case, the nozzle array of the print head 144 Printing is performed using the entire nozzle row 146 without dividing 146 (see FIG. 22) into upstream and downstream. That is, the printer 100 uses the nozzle group 146 to form a color image and a nozzle group to form a toned white image only when performing a printing process for forming a color image and a toned white image. It is sufficient to divide into two types and perform printing.

  In the printing process in each of the above embodiments, at least a part of the toned white image is formed so as to overlap the color image. However, the present invention does not overlap the toned white image and the color image. It can also be applied to print processing.

F3. Modification 3:
The display contents of the toned white designation UI window W1 and the color measurement UI window W2 (FIG. 11) in each of the above embodiments are merely examples, and these display contents can be variously changed. For example, in the toned white designation UI window W1 of each of the above embodiments, the toned white is designated by the color value in the L ^* a ^* b ^* color system (color space). The toned white may be designated by a system (for example, L ^* u ^* v ^* color system). In the toned white designation UI window W1 in each of the above embodiments, the toned white density is designated by the T value, but the designation of the T value may be omitted. In the toned white designation UI window W1 of each of the embodiments described above, the toned white can be designated by colorimetry (see the colorimetric UI window W2), but the toned white by colorimetry is designated. Need not be possible.

F4. Modification 4:
In the above embodiments, the printing process for forming the color image and the toned white image on the print medium PM has been described. However, the present invention is not limited to the combination of the color image and the toned white image, The present invention is applicable to a printing process in which a plurality of images corresponding to each of a plurality of ink groups having different reproduction areas are formed on the print medium PM. For example, from the seven ink colors used in the printer 100, a combination of four colors of cyan, magenta, yellow, and black (ink group), and a combination of three colors of yellow, light cyan, and light magenta (ink group) Are set, the color gamuts of the ink groups are different from each other. In the printing system 10 of each of the above embodiments, at least a part of two images having different color gamuts corresponding to the two ink groups are mutually connected, as in the printing process for forming a color image and a toned white image. It is possible to execute a printing process that forms on the print medium PM so as to overlap. The present invention is not limited to the case where the number of ink groups is two, but can be applied to the case where the number of ink groups is three or more. When the number of ink groups is three or more, the nozzle row 146 of the print head 144 may be divided into three or more nozzle groups, and each nozzle group may print an image corresponding to each ink group.

10 ... Printing system 100 ... Printer 110 ... CPU
112 ... Command processing module 120 ... ROM
130 ... RAM
132: Raster buffer 140 ... Head controller 142 ... Head buffer 144 ... Print head 146 ... Nozzle array 150 ... Carriage controller 152 ... Carriage motor 160 ... Print medium feed controller 162 ... Print medium feed motor 200 ... PC
210 ... CPU
220 ... ROM
230 ... RAM
260 ... Display interface 270 ... Serial interface 300 ... Printer driver 310 ... Ink color separation processing module for color image 320 ... Halftone processing module for color image 330 ... Toned white designation module 332 ... UI control module 340 ... Toned white image Color conversion module 350 ... Toned white image ink color separation processing module 360 ... Toned white image halftone processing module 370 ... Command creation module

Claims (10)

A printing apparatus that performs printing using multiple colors of ink,
A first image forming unit that ejects ink of a first ink group including at least one of the plurality of colors of inks to form a first image on a print medium;
A second image is ejected by ejecting ink of a second ink group that includes at least one of the plurality of colors of ink and has a color reproduction range different from that of the first ink group. And a second image forming unit that forms on the print medium such that at least a part of the second image overlaps the first image. The printing apparatus according to claim 1, further comprising:
The formation of the first image by the first image forming unit and the formation of the second image by the second image forming unit are performed in parallel during at least a part of the printing period. A printing apparatus comprising a control unit that controls the first image forming unit and the second image forming unit. The printing apparatus according to claim 1, further comprising:
A printing apparatus comprising: a head having a first nozzle group as the first image forming unit and a second nozzle group as the second image forming unit. The printing apparatus according to any one of claims 1 to 3,
The plurality of colors of ink includes white ink;
The printing apparatus, wherein the first ink group does not include the white ink, and the second ink group includes the white ink. The printing apparatus according to claim 4, further comprising:
A color designating unit that obtains a density value and a color value in a predetermined color system for the color of the second image;
The printing apparatus, wherein the second image forming unit forms the second image based on the acquired value. The printing apparatus according to claim 5,
The color designation unit is a printing apparatus that acquires at least one of the density value and a color value in the predetermined color system based on a color measurement result of an object. The printing apparatus according to claim 6,
The printing apparatus according to claim 1, wherein the color designation unit acquires at least one of the density value and a color value in the predetermined color system based on a color measurement result on a white background and a color measurement result on a black background. The printing apparatus according to any one of claims 5 to 7,
The printing apparatus, wherein the predetermined color system is one of an L ^* a ^* b ^* color system and an L ^* u ^* v ^* color system. A printing method for printing using a plurality of colors of ink,
(A) ejecting ink of a first ink group including at least one of the inks of the plurality of colors to form a first image on a print medium;
(B) A second image is formed by ejecting ink of a second ink group that includes at least one of the plurality of colors of ink and has a color reproduction range different from that of the first ink group. Forming on the print medium such that at least a part of the second image overlaps the first image. A computer program for controlling a printing apparatus that performs printing using a plurality of colors of ink,
A first image forming function for forming a first image on a print medium by ejecting ink of a first ink group including at least one of the plurality of colors of ink;
A second image is ejected by ejecting ink of a second ink group that includes at least one of the plurality of colors of ink and has a color reproduction range different from that of the first ink group. A computer program that causes a computer to realize a second image forming function that forms on the print medium such that at least a part of two images overlaps the first image.

Images