Print data creation device, transfer system, print data creation method and program

Abstract

Create print data that allows for overprinting while reducing white ink bleeding. [Solution] The image processing unit 38 creates dot data indicating the ink ejection position on media M for each ink color used by printer 2, based on the image data ID. The white plate creation unit 34 adjusts the white print area WPA based on the image data ID when performing overprinting, which involves printing white ink on top of an image printed with color ink. The area determination unit 35 of the white plate creation unit 34 determines the color print area CPA in the image data ID. The contour extraction unit 36 ​​extracts the pixels P that constitute the contour of the color print area CPA. The pixel adjustment unit 37 adjusts the color print area CPA based on the pixels P that constitute the contour to determine the white print area WPA.

Description

Technical Field

[0001] The present invention relates to a print data creation device, a transfer system, a print data creation method, and a program.

Background Art

[0002] DTF (Direct to Film) is one of the transfer methods. In DTF, an image is printed on a film by a printer, and an adhesive is applied to the image. By overlapping the printed surface of the film on the work and performing heat pressing, the image to which the adhesive is applied adheres to the work. After heat pressing, the film is peeled off from the work, and the image is transferred to the work (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When the work is dark or transparent, the color of the image transferred to the work may not be properly visible. In order to improve the visibility of the image, the printer may print white ink over the image. In the transferred work, the white ink is located below the image and functions as a light reflection layer. As a result, even on dark or transparent works, the color of the transferred image can be properly seen.

[0005] A print data creation device creates print data for printing an image by a printer based on the data of the image. The print data includes dot data indicating the ejection position of ink on the medium. When performing overprinting of white ink, the print data creation device creates print data including dot data of color ink constituting the image and dot data of white ink.

[0006] Here, since the white ink functions as a light-reflecting layer, the amount of ink ejected at each dot tends to be higher compared to the colored ink. Therefore, there is a possibility that the white ink may extend beyond the outline of the image on the transferred artwork.

[0007] In print data creation devices, there is a need to create print data that enables overprinting while reducing white ink bleeding. [Means for solving the problem]

[0008] A print data creation apparatus in one aspect of the present invention is (1) A print data creation device that creates print data for printing an image onto a medium using a printing device, A dot data creation unit creates dot data indicating the ink ejection position on the media for each ink color used in the printing device, based on image data, as print data. When performing overprinting, which involves printing white ink on top of an image printed with color ink, the system includes an area adjustment unit that adjusts the printing area of ​​the white ink based on the image data. The aforementioned region adjustment unit is A region determination unit for determining the printing area of ​​the color ink shown in the image data, A contour extraction unit that extracts pixels that constitute the contour of the printed area of ​​the color ink, The system includes a pixel adjustment unit that adjusts the printing area of ​​the color ink based on the pixels that constitute the contour, thereby determining the printing area of ​​the white ink. The dot data creation unit creates dot data for the white ink in addition to the dot data for the color ink, based on the image data and the printing area of ​​the white ink.

[0009] (2) In the print data creation device described in (1) above, The pixel adjustment unit determines the area obtained by excluding the pixels constituting the contour from the printing area of ​​the color ink as the printing area of ​​the white ink.

[0010] (3) In the print data creation device described in (2) above, If there is a non-printing area within the color ink printing area where the color ink is not printed, the contour extraction unit extracts pixels surrounding the non-printing area within the color ink printing area. The pixel adjustment unit defines the area obtained by excluding the pixels constituting the contour and the pixels surrounding the non-printing area from the printing area of ​​the color ink as the printing area of ​​the white ink.

[0011] (4) In the print data creation device described in (2) or (3) above, The pixel adjustment unit defines the area obtained by excluding the pixels extracted by the contour extraction unit from the color ink printing area as the first printing area for the white ink, and the area composed of the pixels extracted by the contour extraction unit as the second printing area for the white ink, which is printed with a smaller ejection amount than the first printing area.

[0012] (5) In the print data creation device described in (2) or (3) above, The pixel adjustment unit defines the area obtained by excluding the pixels extracted by the contour extraction unit from the color ink printing area as the white ink printing area, and the area composed of the pixels extracted by the contour extraction unit as the transparent ink printing area.

[0013] (6) In the print data creation device described in (2) or (3) above, The pixel adjustment unit sets the area obtained by excluding the pixels extracted by the contour extraction unit from the color ink printing area as the white ink printing area. If there is a narrow area in the printing area of ​​the white ink, the pixel adjustment unit incorporates at least a portion of the pixels surrounding the narrow area from the excluded area into the narrow area.

[0014] (7) In the printing data creation device according to (6) above, The pixel adjustment unit sets pixels constituting the narrow portion as an area where the white ink is printed with a discharge amount less than the set discharge amount or an area where the transparent ink is printed.

[0015] (8) A transfer system including the printing data creation device according to any one of (1) to (7) above, Based on the printing data created by the printing data creation device, a printing device that prints the image on the medium with the color ink and prints the white ink over the image, An adhesive applying device that applies an adhesive to the white ink printed on the medium, A pressing device that transfers the image to which the adhesive has been applied to the workpiece by pressing the printed surface of the medium against the workpiece, is provided.

[0016] A printing data creation method according to an aspect of the present invention is (9) A printing data creation method for creating printing data for printing an image on a medium by a printing device, Based on the image data, a dot data creation process for creating, as the printing data, dot data indicating the discharge position of the ink on the medium for each color of the ink used in the printing device, When performing overprinting of printing the white ink over the image printed with the color ink, an adjustment process for adjusting the printing area of the white ink based on the image data, including: The adjustment process includes An area determination process for determining the printing area of the color ink shown in the image data, A contour extraction process for extracting pixels constituting the contour of the printing area of the color ink, A pixel adjustment process for adjusting the printing area of the color ink based on the pixels constituting the contour to determine the printing area of the white ink. In the dot data creation process, based on the image data and the printing area of the white ink, in addition to the dot data of the color ink, dot data of the white ink is created.

[0017] A program according to an aspect of the present invention is (10) A program for creating print data for printing an image on a medium by a printing device, causing a computer to perform a dot data creation process of creating, as the print data, dot data indicating the ejection position of ink on the medium for each color of ink used in the printing device based on the image data; when performing overprinting of overprinting the white ink on the image printed with the color ink, perform an adjustment process of adjusting the printing area of the white ink based on the image data, wherein the adjustment process includes an area determination process of determining the printing area of the color ink indicated in the image data; a contour extraction process of extracting pixels constituting the contour of the printing area of the color ink; and a pixel adjustment process of adjusting the printing area of the color ink based on the pixels constituting the contour to determine the printing area of the white ink. In the dot data creation process, based on the image data and the printing area of the white ink, in addition to the dot data of the color ink, dot data of the white ink is created.

Advantages of the Invention

[0018] According to the present invention, it is possible to create print data capable of performing overprinting with reduced bleeding of white ink.

Brief Description of the Drawings

[0019] [Figure 1] It is a diagram showing a configuration example of a transfer system. [Figure 2] It is a schematic diagram explaining a process executed by the transfer system. [Figure 3] This diagram shows the hardware configuration of the control unit. [Figure 4] This diagram shows the functional configuration of the control device. [Figure 5] This diagram illustrates the effect of overprinting with white ink. [Figure 6] (a) is a diagram showing white image data created without applying pixel adjustment processing to the image data. (b) is a diagram showing white image data created after applying pixel adjustment processing to the image data. [Figure 7] (a) is a diagram illustrating the processing mode of the region determination unit, and (b) is a diagram illustrating the processing mode of the contour extraction unit and the pixel adjustment unit. [Figure 8] This flowchart shows the processing flow of the print data creation unit when white ink overprinting is set as a printing condition. [Figure 9] (a) is a diagram showing the processing modes of the contour extraction unit and the pixel adjustment unit according to Modification 1. (b) is a diagram showing examples of setting the density of white ink and the dot size in the first and second printing areas. [Figure 10] This figure shows the processing method of the pixel adjustment unit according to modified example 2. [Figure 11] This figure shows the processing method of the pixel adjustment unit according to modified example 3. [Modes for carrying out the invention]

[0020] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In this embodiment, an example of applying a print data creation device to a transfer system is described. Figure 1 shows an example of the configuration of the transcription system 1. Figure 2 is a schematic diagram illustrating the process performed in the transfer system 1. Note that although Figure 2 is a cross-sectional view, the white ink layer WHL and the receiving layer RL of the media M are shown without hatching. Figure 2(a) shows the process of printing an image onto media M. Figure 2(b) shows the process of forming an adhesive layer AL on the image. Figure 2(c) shows the process of pressing media M and workpiece WK together. Figure 2(d) shows the process of peeling media M from workpiece WK.

[0021] As shown in Figure 1, the transfer system 1 includes, for example, a printer 2 (printing device), a control device 3 for the printer 2 (print data creation device), a shaker 4 (adhesive application device), and a hot press 8 (pressing device). The X, Y, and Z directions shown in Figure 1 are for illustrative purposes only, illustrating an example of the positional relationship between printer 2 and shaker 4. The Z direction is along the vertical direction (direction of gravity), corresponding to the up and down directions on the paper in Figure 1. The X and Y directions are along the horizontal direction, perpendicular to the Z direction. Note that the thickness of media M in the heat press machine 8 in Figure 1 is exaggerated for illustrative purposes.

[0022] In transfer system 1, for example, an image can be transferred to a workpiece WK using a transfer method called DTF (Direct to Film) to produce printed materials. In DTF, an image printed on media M is transferred to the workpiece WK. Specifically, as shown in Figure 1, the printer 2 prints an image onto the media M. The shaker 4 applies hot melt powder HP (adhesive) to the image printed on the media M. The shaker 4 also heats the media M, melting the hot melt powder HP applied to the image and forming an adhesive layer AL (see Figure 2(b)). Next, the media M with the printed image is placed on top of the workpiece WK and heated and pressed by the hot press machine 8. This adheres the image with the adhesive layer AL to the workpiece WK. After pressing, the media M is peeled off the workpiece WK, transferring the image to the workpiece WK.

[0023] As shown in Figure 2(a), the media M can be, for example, a resin film on which an ink receiving layer RL is formed on a substrate BM. Alternatively, a media other than film, such as paper, may be used, as long as it is treated to allow the ink to be peeled off after transfer. Work WK can be made from various materials such as cotton, polyester, nylon, leather, nonwoven fabrics, wood, metal plates, or a combination of at least some of these. Work WK can be made from these materials to create clothing such as T-shirts, or fabric products such as tapestries and banners.

[0024] As shown in Figure 1, the printer 2 can be, for example, an inkjet printer that prints by ejecting droplet-shaped ink from nozzles 23. In Figure 1, as an example, the printer 2 is shown printing while unwinding a roll-shaped media M and transporting it in the X direction. The printer 2 includes a platen 21 that supports the media M, and a head 22 that is positioned opposite the platen 21 in the Z direction and ejects ink onto the media M supported by the platen 21. The print head 22 is positioned with a gap between it and the upper surface of the platen 21. Multiple nozzles 23, which are ink discharge ports, are provided on the lower surface of the print head 22 facing the platen 21. The print head 22 is movable in the Y direction by a moving mechanism (not shown).

[0025] A shaft 24 is provided on the X1 side of the platen 21, which is rotatable about an axis Y1 along the Y direction. Media M is wound in a roll shape and supported on the outer circumference of the shaft 24. When media M is fed to the X2 side by a dispensing mechanism (not shown), the shaft 24 rotates clockwise about the axis Y1 to unwind the media M. Media M is wrapped around the top surface of the platen 21 in a direction that crosses in the X direction. Ink is ejected from the nozzle 23 of the head 22 onto the media M located on the top surface of the platen 21.

[0026] Although detailed illustrations are omitted, the print head 22 of printer 2 is equipped with a nozzle row consisting of multiple nozzles 23, and each nozzle row can be configured to eject different types of ink. While the ink used in Printer 2 is not limited to a specific type, water-based ink can be used with DTF. The ink can be, for example, an ink containing a pigment, which is a coloring agent. Inks containing pigments can be, for example, process color inks of C (cyan), M (magenta), Y (yellow), and K (black) (hereinafter referred to as "color inks"), or white ink. White ink can contain a colorless or white coloring agent as the ink's coloring agent and may have a light-reflecting pigment. Alternatively, the ink can be a clear ink (transparent ink) that does not contain coloring agents such as pigments or dyes.

[0027] Figure 2(a) shows an example in which an image to be transferred to the workpiece WK is printed on media M using color ink, and white ink is printed on top of the image. In this case, a color ink layer COL is formed on the surface of media M, and a white ink layer WHL is formed on top of the color ink layer COL. The color ink layer COL and the white ink layer WHL are collectively referred to as the "ink layer IL".

[0028] As shown in Figure 1, the media M, after the printing process is complete, is fed out from the platen 21 by a feeding mechanism (not shown) and delivered to the shaker 4 located on the X2 side of the printer 2. Although Figure 1 illustrates a printer 2 that corresponds to a roll-shaped media M, the printer 2 may also print on, for example, a sheet-shaped or board-shaped media M. In this case, the printer 2 may include a flattable-type platen 21 and a moving mechanism that moves the head 22 relative to the platen 21 in the X and Y directions.

[0029] As shown in Figure 1, the shaker 4 includes an application unit 41 for applying hot melt powder HP to the media M, a heating unit 44 for heating the media M to which the hot melt powder HP has been applied, and a winding unit 47 for winding the dried media M into a roll shape. The components are arranged in the order of the applying unit 41, the heating unit 44, and the winding unit 47, from the X1 side to the X2 side in the X direction. The winding unit 47 includes a shaft 48 arranged along the Y direction and a motor (not shown) that rotates the shaft 48 about an axis Y2 along the Y direction. The media M is wound in a roll shape around the outer circumference of the shaft 48 and supported. When the motor drives the shaft 48 to rotate counterclockwise about the axis Y2, the media M fed from the printer 2 is transported to the X2 side in the X direction, passes through the application unit 41 and the heating unit 44, and is wound around the outer circumference of the shaft 48.

[0030] As shown in Figure 1, a support portion 45 for supporting the media M is provided on the lower side in the Z direction of the heating portion 44 of the shaker 4. A recess Mb for the media M is formed on the lower side in the Z direction of the dispensing portion 41 of the shaker 4. When the media M is fed into the shaker 4, it hangs down in the Z direction due to its own weight between the platen 21 of the printer 2 and the support portion 45 provided on the lower side in the Z direction of the heating portion 44, thereby forming the recess Mb. The recess Mb is formed in a position that overlaps with the dispensing portion 41 when viewed from the Z direction.

[0031] The application unit 41 can consist of, for example, a nozzle that sprays hot melt powder HP. The application unit 41 supplies hot melt powder HP to a recess Mb in the media M located below it. As a result, the hot melt powder HP supplied from the application unit 41 accumulates in the recess Mb. When the media M passes through the recess Mb, it comes into contact with the hot melt powder HP accumulated in the recess Mb. The hot melt powder HP comes into contact with the ink that makes up the image printed on the media M. Since the media M is delivered directly from the printer 2 to the shaker 4, the ink printed on the media M is not completely dry, and moisture remains on the surface. Therefore, the hot melt powder HP that comes into contact with the ink adheres to the ink.

[0032] A vibration mechanism 45a is built into the support section 45 located on the X2 side of the application section 41. Since the media M is supported by the support section 45, the vibration of the vibration mechanism 45a is transmitted to the entire media M being transported by the shaker 4 via the support section 45. The vibration of the media M causes the hot melt powder HP to move on the media M, making it easier for it to adhere to the ink. In addition, the vibration of the media M allows any excess hot melt powder HP that is not adhering to the ink to fall off the media M.

[0033] Hot melt powder HP can be any known type used for DTF. Suitable hot melt powder HP may include, for example, resin powders containing urethane, acrylic, polyester, polyamide, or mixtures thereof. Alternatively, hot melt powder HP may be primarily composed of a thermoplastic polymer and may not contain water or organic solvents. Hot melt powder HP that is solid at room temperature and melts and becomes tacky when heated can be used. Alternatively, instead of providing a nozzle or other attachment part 41, the user may manually supply the hot melt powder HP to the recessed part Mb of the media M.

[0034] As shown in Figure 1, the heating unit 44 includes a heater 46 for heating the media M. The heater 46 heats the media M, drying any undried ink and melting and fixing the hot melt powder HP attached to the ink. Furthermore, the melted hot melt powder HP becomes adhesive. As a result, as shown in Figure 2(b), an adhesive layer AL is formed on the upper side of the ink layer IL formed on the surface of the media M.

[0035] In Figure 1, the shaker 4 is shown as an example in which a heater 46, which is a mechanism for heating the media M, is integrated into the shaker 4. However, a mechanism for heating the media M may be provided separately from the shaker 4. For example, if the media M is in sheet form rather than roll form, an oven or the like can be provided as a heating mechanism for the media M. The heating conditions for media M are not limited, but for example, it is conceivable to maintain a heating temperature of around 130°C (e.g., around 120-150°C) for about 5 minutes (e.g., 1-10 minutes).

[0036] The media M that has passed through the heating section 44 is wound into a roll on the shaft 48 of the winding section 47. The user cuts out the area containing the image to be transferred to the workpiece WK from the media M wound on the shaft 48 and superimposes it onto the workpiece WK. At this time, as shown in Figure 2(c), the side of the media M on which the ink layer IL and adhesive layer AL are formed (the printed side of the image) is placed opposite the surface of the workpiece WK. The adhesive layer AL formed on the surface of the ink layer IL comes into contact with the surface of the workpiece WK. The user presses the workpiece WK, which consists of multiple layers of media M, with the hot press machine 8.

[0037] As shown in Figure 1, the hot press machine 8 comprises a mounting section 81 on which the workpiece WK is placed, and a pressing section 82 positioned above the mounting section 81 in the Z direction, which presses the workpiece WK by sandwiching it between the mounting section 81 and the pressing section 82. A heater 83 is built into the mounting section 81. The user places the workpiece WK, with media M stacked on top of each other, on the mounting section 81 and drives the heater 83 to heat the media M. The user presses down the press section 82, sandwiching and pressing the workpiece WK between the press section 82 and the mounting section 81. As shown in Figure 2(c), the ink layer IL with the adhesive layer AL is pressed onto the surface of the workpiece WK and adheres to the workpiece WK.

[0038] After the pressing process is complete, the user removes the workpiece WK from the hot press machine 8 and peels the media M from the workpiece WK and the ink layer IL adhered to it. As shown in Figure 2(d), in the transferred workpiece WK, the color ink layer COL is superimposed on the white ink layer WHL. This makes the image printed with color ink visible.

[0039] Furthermore, to further fix the image transferred to the workpiece WK, pressing may be performed again after peeling off the media M. In this case, paper or the like may be placed between the workpiece WK placed on the mounting section 81 of the hot press machine 8 and the pressing section 82 before pressing. This reduces the likelihood of the image peeling off the workpiece WK during pressing.

[0040] The control device 3 controls the operation of the printer 2. The control device 3 also acts as a print data creation device, creating print data for printing images on the printer 2. Figure 3 shows the hardware configuration of the control device 3. As shown in Figure 3, the control device 3 can be composed of a general-purpose information processing device 9 (computer). The information processing device 9 can be, for example, a personal computer, a mobile terminal such as a smartphone, or a tablet terminal. Figure 3 is a block diagram showing an example of the hardware configuration of the information processing device 9. As shown in Figure 3, the information processing device 9 includes a CPU (Central Processing Unit) 901, ROM (Read Only Memory) 902, RAM (Random Access Memory) 903, HDD (Hard Disk Drive) 904, display 905, input device 906, communication interface 907, and media interface 908, etc. Each component is interconnected by a bus.

[0041] The CPU 901 controls the entire information processing unit 9. The CPU 901 can load the OS and various programs stored in the ROM 902 or HDD 904 into the RAM 903 and execute them. Alternatively, the CPU 901 can load programs stored in the storage medium RM into the RAM 903 via the media I / F 908 and execute them. The storage medium RM can be an optical storage medium, a magneto-optical storage medium, a magnetic storage medium, a conductive memory tape medium, a semiconductor memory, etc. Furthermore, the information processing device 9 may also be equipped with a GPU (Graphics Processing Unit) or the like, in addition to the CPU 901, as a processor. The CPU 901 processes data in response to user input via the input device 906 and displays the processing results on the display 905. The input device 906 can be, for example, a keyboard, mouse, touchpad, touch panel, physical switch, etc.

[0042] HDD904 stores programs executed by CPU901 and data used by those programs. Alternatively, an SSD (Solid State Drive) may be provided instead of, or in addition to, HDD904. Communication I / F907 outputs data received from other devices (printer 2 or other information processing devices) via a network such as the Internet or LAN (Local Area Network) to CPU901. Communication I / F907 also transmits data generated by CPU901 to other devices. CPU901 may also load necessary programs onto RAM903 from other devices via the network. The CPU 901 executes the application program loaded onto the RAM 903, thereby realizing the functional configuration of the control unit 3.

[0043] Figure 4 shows the functional configuration of the control device 3. As shown in Figure 4, the control device 3 includes a print control unit 30 that controls the operation of the printer 2, and a print data creation unit 31 that creates print data PD for printing an image on the printer 2. The print control unit 30 controls the operation of each part of the printer 2 based on the print data PD created by the print data creation unit 31. The print data creation unit 31 includes an image data acquisition unit 32, a print condition setting unit 33, a white plate creation unit 34 (area adjustment unit), and an image processing unit 38 (dot data creation unit).

[0044] The image data acquisition unit 32 imports an image data ID containing the image to be printed on media M in response to user input. The user may, for example, import an image data ID created by an external information processing device into the control device 3. Alternatively, if image data creation software is installed in the control device 3, the control device 3 may create the image data ID.

[0045] The print condition setting unit 33 can set various print conditions when printing an image onto media M in response to user input. Print conditions can include, for example, the type and size of media M used for printing, the type of ink to use, print quality, print speed, and overprinting. Overprinting refers to printing an image with color ink on top of or below an image that has already been printed with color ink, such as white ink (W) or clear ink (CL). The print condition setting unit 33 can, for example, set the type of ink to be used for overprinting and the direction in which the ink is applied to the image (upper or lower). In this embodiment, we will primarily describe a method of printing by overlaying white ink on top of the image.

[0046] Figure 5 illustrates the effect of overprinting with white ink. Figure 5(a) shows the state after an image without white ink overprinting has been transferred to a white workpiece WK. Figure 5(b) shows the state after an image without white ink overprinting has been transferred to a dark-colored workpiece WK. Figure 5(c) shows the state after an image with white ink overprinting has been transferred to a dark-colored workpiece WK. Note that the adhesive layer AL (see Figure 2) is not shown in Figure 5. Also, white workpieces WK are hatched, and dark-colored workpieces WK are cross-hatched to distinguish them.

[0047] As shown in Figure 5(a), a color ink layer COL that constitutes the image is formed on the surface of the workpiece WK after transfer. In the case of a white workpiece WK, light L irradiated onto the color ink layer COL is reflected from the surface of the workpiece WK, passes through the color ink layer COL, and enters the user's eye. This allows the user to see the colors of the image. On the other hand, as shown in Figure 5(b), in the case of a dark-colored workpiece WK, the light L irradiated onto the color ink layer COL is absorbed by the surface of the workpiece WK and is less likely to be reflected. As a result, the amount of light L incident on the user's eye is reduced, making it difficult to see the colors of the image.

[0048] As shown in Figure 5(c), when white ink is overprinted, a white ink layer WHL is formed between the surface of the dark-colored workpiece WK and the color ink layer COL. In this case, light L irradiated onto the color ink layer COL is reflected by the white ink layer WHL, passes through the color ink layer COL, and enters the user's eye. This makes the image's colors easier to see. Thus, when overprinting is performed, the white ink layer WHL functions as a reflective layer, which can improve the visibility of the image's colors even when the image is transferred to a dark-colored workpiece WK.

[0049] The white plate creation unit 34 shown in Figure 4 creates white plate image data WD based on the image data ID when white ink overprinting is set as a printing condition. Details of the white plate image data WD and the processing of the white plate creation unit 34 will be described later.

[0050] The image processing unit 38 performs processing to create print data PD based on the image data ID. The print data PD includes dot data created for each ink color used to print the image in the printer 2. The image processing unit 38 creates dot data by performing processes such as color conversion, halftone processing, and rasterization on the image data ID. The dot data indicates the ink ejection position on the media M. The dot data is created, for example, as a binarized TIFF file, and for each coordinate point of media M, it shows in binary whether there is an ink dot (ejection) or not.

[0051] As shown in Figure 4, the image processing unit 38 creates dot data indicating the ejection positions of each of the CMYK color inks based on the image data ID imported by the image data acquisition unit 32. When performing overprinting with white ink, in addition to the CMYK dot data, the image processing unit 38 creates dot data indicating the ejection position of the white ink (W) based on the white plate image data WD created by the white plate creation unit 34.

[0052] The image processing unit 38 adds necessary data such as commands according to the specifications of printer 2, thumbnail files, and job information definition files to the created dot data to create the final print data PD, and outputs it to the print control unit 30.

[0053] The print control unit 30 refers to the dot data of each ink, moves the head 22 of the printer 2 to the coordinate point of the media M where the presence of ink dots is specified, and ejects ink from the corresponding nozzle 23. The print data PD also includes the amount of ink ejected per drop for each ink used in printing. The more ink ejected from nozzle 23, the larger the dot size of the ink that lands on media M. The dot size is controlled according to the ink ejection amount, for example, to L dot (ejection amount of 18pL to 22pL per dot), M dot (ejection amount of about 70 to 80% of L dot), S dot (ejection amount of about 40 to 50% of L dot), etc.

[0054] The following describes the details of the processing in the white version creation section 34. As described above, the white plate creation unit 34 creates white plate image data WD, which is used in the image processing unit 38 to create dot data for white ink. The white plate image data WD indicates the printing area for white ink. In this embodiment, when creating the white plate image data WD, the white plate creation unit 34 performs adjustment processing to reduce white ink bleeding.

[0055] Figure 6(a) shows the white version image data WD created from the image data ID without pixel adjustment processing. Figure 6(b) shows the white version image data WD created from the image data ID after pixel adjustment processing. Figure 6 shows an example image where the center of a circle (hatched area in the figure) printed with color ink is outlined in white in the shape of a star.

[0056] In the image data ID in Figure 6(a), the circular area excluding the star shape is the area that will be printed with color ink (hereinafter referred to as the "color printing area CPA"). The area around the circle and the star shape in the center of the circle are non-printing areas NPA1 and NPA2, where color ink will not be printed.

[0057] Specifically, an image data ID is a collection of pixels P, and the color print area CPA and the non-print areas NPA1 and NPA2 are each composed of consecutive pixels P. In the image data ID, color information is specified for each pixel P. Each pixel P that makes up the color printing area CPA is assigned color information (RGB values) corresponding to the color to be printed (see the area within the dashed-dotted frame in the diagram). Pixels P that constitute the color printing area CPA are specified as having "dots" for color ink in the dot data described above (see Figure 4). Pixels P that constitute the non-printing areas NPA1 and NPA2 are specified as not having "dots" for color ink in the dot data.

[0058] When performing overprinting with white ink, for example, one might consider printing white ink across the entire surface of a pixel P that will be printed with color ink. In this case, as shown in Figure 6(a), the color print area CPA of the image data ID is used directly as the area to be printed with white ink (hereinafter referred to as the "white print area WPA") to create the white image data WD. However, if the color print area CPA is used directly as the white print area WPA, there is a possibility that the white ink may easily bleed around the outline of the image printed with color ink.

[0059] As mentioned above, the white ink layer WHL (see Figure 5(c)) formed by overprinting functions as a reflective layer. To increase light reflectivity, in overprinting, the white ink dot size is usually L dot, and the duty cycle (printing rate) is set to 100%, meaning that printing is performed by ejecting across the entire area of ​​the ejection position. In this case, as shown within the dashed-dot frame in Figure 6(a), the white ink dot D may become larger than the pixel P. Furthermore, when the white ink lands on the media M, the wetting spreads, causing the white ink dot D to become even larger. This can cause white ink to bleed outside the outline of an image printed with color ink. Furthermore, if there is a non-printing area (NPA2) within the color printing area (CPA), white ink may bleed inside the non-printing area (NPA2). When an image with white ink bleeding is transferred to a dark-colored workpiece (WK), the bleeding becomes more noticeable and may affect the quality of the printed material.

[0060] To reduce such white ink bleeding, the white plate creation unit 34 performs pixel adjustment processing on the white printing area WPA when creating the white plate image data WD. As shown in Figure 4, the white plate creation unit 34 includes a region determination unit 35, a contour extraction unit 36, and a pixel adjustment unit 37. The area determination unit 35 determines the color print area (CPA) and the non-print area (NPA) within the color print area (CPA) based on the image data ID. The contour extraction unit 36 ​​extracts pixels P that constitute the contour of the color printing area CPA. If there is a non-printing area NPA within the color printing area CPA, the contour extraction unit 36 ​​also extracts pixels P that surround the non-printing area NPA within the color printing area CPA. The pixel adjustment unit 37 adjusts the pixels P that constitute the white printing area WPA based on the pixels P extracted by the contour extraction unit 36 ​​(the pixels P that constitute the contour of the color printing area CPA and the pixels P that surround the non-printing area NPA). The pixel adjustment unit 37 creates white image data WD based on the adjusted white printing area WPA.

[0061] Specifically, as shown in Figure 6(b), the pixel adjustment unit 37 determines the white printing area WPA to be the area obtained by excluding the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) from the color printing area CPA. The white print area (WPA) after pixel adjustment is a reduced version of the color print area (CPA) of the image data ID. Furthermore, the non-print areas (NPA1 and NPA2) are expanded versions of the non-print areas (NPA1 and NPA2) of the image data ID.

[0062] During the pixel adjustment process, for pixels P excluded from the white print area (WPA), color ink is ejected, but white ink is not. In other words, white ink is not ejected to pixels in the outer contours of images or the contours of white areas, where white ink bleeding is likely to occur. This reduces white ink bleeding.

[0063] A more specific example of the pixel adjustment process will be explained. Figure 7(a) illustrates the processing mode of the region determination unit 35, and Figure 7(b) illustrates the processing mode of the contour extraction unit 36 ​​and the pixel adjustment unit 37. In Figure 7, the letter "P" is shown as an example image, and a magnified view of pixel P of the image data is shown. Note that the X and Y directions in the figure correspond to coordinates in the data and are different from the X and Y directions shown in Figure 1.

[0064] As shown in Figure 7(a), the region determination unit 35 determines the color print area CPA and the non-print areas NPA1 and NPA2 in the image data ID. Known image processing methods can be used for the processing of the region determination unit 35. The area determination unit 35 can determine, for example, that an area in which one or more pixels P with color information other than white are continuous in the X direction, Y direction, or diagonal direction is a color printing area CPA. The area determination unit 35 can also determine that an area in which one or more pixels P with color information of white are continuous in the X direction, Y direction, or diagonal direction is a non-printing area NPA1, NPA2.

[0065] In the example shown in Figure 7(a), the region determination unit 35 determines that the region consisting of pixels P marked with ● is the color printing region CPA. The region determination unit 35 also determines that the regions consisting of pixels P marked with × are the non-printing regions NPA1 and NPA2. Non-printing region NPA1 is a non-printing region outside the color printing region CPA, and non-printing region NPA2 is a non-printing region inside the color printing region CPA.

[0066] The contour extraction unit 36 ​​can extract pixels P that constitute the contour in the color printing area CPA determined by the area determination unit 35, for example, using an image processing method such as a known edge detection method. In the example shown in Figure 7(b), the region determination unit 35 extracts the pixels P marked with a triangle as pixels P that constitute the outline of the color printing region CPA. The "pixels P that constitute the outline of the color printing area CPA" include at least the outermost pixel P of the color printing area CPA. The "pixels that constitute the outline of the color printing area CPA" may also include a predetermined number of pixels P arranged in the X, Y, or diagonal directions relative to the outermost pixel P. The "predetermined number" is not limited to a specific number and can be set as appropriate. Furthermore, the "predetermined number" may be the same number in the X, Y, and diagonal directions, or different numbers may be set. The outline extraction unit 36 ​​may also change the "predetermined number" as appropriate according to the size of the color printing area CPA and perform processing accordingly.

[0067] If there is a non-printing area NPA2 within the color printing area CPA, the contour extraction unit 36 ​​can extract pixels P surrounding the non-printing area NPA in the color printing area CPA using known image processing methods such as edge detection. In the example shown in Figure 7(b), the region determination unit 35 extracts the pixels P marked with a square as pixels P that surround the non-printed area NPA2 within the color printing area CPA. The "pixels P surrounding the non-printable area NPA2" can be a predetermined number of pixels P arranged in the X, Y, or diagonal direction with respect to at least the outermost pixel P of the non-printable area NPA2. The "predetermined number" is not limited to a specific number and can be set as appropriate. Furthermore, the "predetermined number" may be the same number in the X, Y, and diagonal directions, or it may be a different number in each direction.

[0068] The pixel adjustment unit 37 can, for example, exclude pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P surrounding the non-printing area NPA2) from the color printing area CPA, and make the remaining area the white printing area WPA. In the example in Figure 7(b), the area consisting of pixels marked with ●, after excluding the pixels P marked with △ and □ from the color print area CPA, becomes the white print area WPA. The pixels P marked with △ and □ are incorporated into the non-print areas NPA1 and NPA2.

[0069] The pixel adjustment unit 37 changes the color information of pixels P that constitute the white printing area WPA to a single color such as black. At this time, the pixel adjustment unit 37 changes the color information of pixels P that have been excluded from the white printing area WPA (pixels P marked with △ and □) to white (R:255, G:255, B:255). This creates the white version image data WD. The image processing unit 38 (see Figure 4) can create white ink dot data by performing a color replacement process to replace the color information of the white image data WD with white, and then performing the aforementioned color conversion process.

[0070] Figure 8 is a flowchart showing the processing flow of the print data creation unit 31 when white ink overprinting is set as a printing condition. As shown in Figure 8, the area determination unit 35 of the white plate creation unit 34 acquires the image data ID imported into the control device 3 (step S01). The region determination unit 35 determines the color print area CPA and the non-print areas NPA1 and NPA2 based on the image data ID (Step S02: Region determination process). The contour extraction unit 36 ​​extracts pixels P that constitute the contour of the color printing area CPA, and if there is a non-printing area NPA2 within the color printing area CPA, it extracts pixels P that surround the non-printing area NPA2 within the color printing area CPA (Step S03: Pixel extraction process). The pixel adjustment unit 37 adjusts the white printing area WPA based on the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) (step S04: pixel adjustment process). Steps S02 to S04 correspond to adjustment processes that adjust the white print area (WPA) based on the image data. The pixel adjustment unit 37 creates white plate image data WD based on the adjusted white print area WPA (Step S05: White plate creation process).

[0071] The image processing unit 38 creates dot data for color ink and dot data for white ink based on the image data ID and white plate image data WD (Step S06: Dot data creation process). The image processing unit 38 adds necessary data such as commands according to the specifications of the printer 2, a thumbnail file, and a job information definition file to the created dot data to create the final print data PD, and outputs it to the print control unit 30 (step S07). The print control unit 30 controls the printer 2 based on the input print data PD and causes it to perform overprinting.

[0072] As described above, the control device 3 (print data creation device) described in the embodiment has, for example, the following configuration. (1) The control device 3 creates print data PD. Print data PD is data for printing an image onto media M using printer 2 (printing device). The control device 3 comprises an image processing unit 38 (dot data creation unit) and a white plate creation unit 34 (area adjustment unit). The image processing unit 38 creates dot data included in the print data PD (step S06, dot data creation process). Based on the image data ID, the dot data indicates the ink ejection position on the media M for each ink color used by the printer 2. The white plate creation unit 34 adjusts the white print area WPA, which is the printing area for white ink, based on the image data ID when performing overprinting, which involves printing white ink on top of an image printed with color ink. The white version creation unit 34 includes a region determination unit 35, a contour extraction unit 36, and a pixel adjustment unit 37. The area determination unit 35 determines the color printing area CPA, which is the printing area of ​​the color ink indicated by the image data ID (step S02, area determination process). The contour extraction unit 36 ​​extracts pixels P that constitute the contour of the color printing area CPA (step S03, pixel extraction process). The pixel adjustment unit 37 adjusts the color printing area CPA based on the pixels P that constitute the contour to determine the white printing area WPA (step S04, pixel adjustment process). The image processing unit 38 creates dot data for white ink in addition to dot data for color ink based on the image data ID and the white print area WPA (step S06, dot data creation process). For example, the pixel adjustment unit 37 creates white plate image data WD that indicates the determined white printing area WPA. The image processing unit 38 can perform color conversion processing on the white plate image data WD to create white ink dot data.

[0073] Furthermore, the transfer system 1 described in the embodiment includes, for example, the following configuration. (11) The transfer system 1 comprises the control device 3 described above, a printer 2 (printing device), a shaker 4 (adhesive application device), and a hot press 8 (pressing device). Printer 2 prints an image onto media M using color inks based on the print data PD created by the control unit, and then prints white ink over the image. Shaker 4 applies hot melt powder HP (adhesive) to the white ink printed on media M. In shaker 4, media M is heated, melting the hot melt powder HP applied to the image, thereby forming an adhesive layer AL on the image. By placing the printed surface of media M onto workpiece WK and heating and pressing it with a heat press machine 8, the image with the adhesive layer AL formed on it can be transferred to workpiece WK.

[0074] In DTF, one of the transfer methods, an image printed on media M is coated with hot melt powder HP and melted. Then, media M is placed on top of work WK and heat-pressed to transfer the image to work WK. Images can be printed using color inks, but if the workpiece WK to be transferred is dark in color, the light L irradiated onto the image may be absorbed by the workpiece WK, affecting the visibility of the image's colors. By performing overprinting with printer 2, a white ink layer WHL is formed beneath the color ink layer COL that makes up the image. The white ink layer WHL reflects the light L, improving the visibility of the image's colors even on dark workpiece WKs.

[0075] In overprinting, it is desirable to print the white ink layer (WHL) as a reflective layer using L-dots with a duty cycle (print density) of 100%. However, in this case, the dot size of the white ink may become larger than the pixels (P) that make up the image. This can cause the white ink to bleed out from the outlines and white areas of the image. This bleeding is particularly noticeable in dark-colored workpieces (WK), and can affect the quality of the printed material.

[0076] In the control device 3 of this embodiment, when performing overprinting of white ink, the white printing area WPA is adjusted based on the image data ID. Specifically, the contour extraction unit 36 ​​of the white plate creation unit 34 extracts the pixels P that constitute the contour from the color printing area CPA indicated by the image data ID. The pixel adjustment unit 37 determines the pixels P that constitute the white printing area WPA based on the extracted pixels P. This adjustment process can reduce the amount of white ink that spills over the edges of images printed with color inks.

[0077] In this embodiment, the pixel adjustment unit 37 creates white plate image data WD indicating the determined white printing area WPA, and the image processing unit 38 performs color conversion processing on the white plate image data WD to create white ink dot data. However, the embodiment is not limited to this. For example, instead of creating white plate image data, the pixel adjustment unit 37 may output information to the image processing unit 38 about pixels P that are to be excluded in the white printing area WPA (pixels P that constitute the outline of the color printing area CPA and pixels P that surround the non-printing area NPA2). The image processing unit 38 may create white ink dot data based on the image data ID and the information about the pixels P to be excluded. For example, the image processing unit 38 can create white ink dot data by excluding the pixels P to be excluded from the pixels that are specified as "with dots" in the color ink (CMYK) dot data created from the image data ID.

[0078] Furthermore, although this embodiment describes an example of application to a transfer system 1 that performs DTF, the invention is not limited to this example. The image printed on the media may be used as a printed material without being transferred to the workpiece WK. For example, if the media M on which the image is printed is dark in color, white ink may be printed on top of the image printed with color ink to form a reflective layer. In this case as well, the adjustment process of this embodiment can reduce the amount of white ink that spills out from the image.

[0079] (2) The pixel adjustment unit 37 can, for example, make the area obtained by excluding the pixels P that constitute the contour from the color printing area CPA into a white printing area WPA.

[0080] By making these adjustments, the white ink will not be overprinted on the outer contours of the image, where white ink bleeding is most likely to occur. This reduces white ink bleeding.

[0081] (3) If there is a non-printing area NPA2 within the color printing area CPA, the contour extraction unit 36 ​​extracts pixels P surrounding the non-printing area NPA2 in the color printing area CPA. The pixel adjustment unit 37 can make the area obtained by excluding the pixels P that constitute the contour and the pixels P surrounding the non-printing area NPA2 from the color printing area CPA into a white printing area WPA.

[0082] Similar to the outlines of an image, white areas are prone to white ink bleeding. By excluding pixels P surrounding the non-printable area NPA2 from the white printable area WPA, white ink bleeding in the white areas can be reduced.

[0083] (8) White ink may be an ink having a light-reflective pigment. As a result, in the workpiece WK onto which the image has been transferred, the white ink layer WHL functions as a light-reflecting layer L, thereby improving the visibility of the image's colors even in dark-colored workpieces WK.

[0084] (9, 10) The transparent ink may be an ink that does not contain pigment or dye. This makes it less noticeable if the transparent ink extends beyond the image.

[0085] (i) The contour extraction unit 36 ​​can extract at least the outermost pixel P of the color printing area CPA as the pixels P that constitute the contour. The contour extraction unit 36 ​​can also extract a predetermined number of pixels P that are aligned with the outermost pixel P as the pixels P that constitute the contour. For example, the contour extraction unit 36 ​​can extract a predetermined number of pixels P that are aligned in the X direction, Y direction, or diagonal direction with respect to the outermost pixel P.

[0086] By excluding not only the outermost pixel P from the white printing area (WPA), but also a predetermined number of pixels P adjacent to the outermost pixel P, white ink bleeding can be appropriately reduced. Note that the "predetermined number" is not limited to a specific number and can be set as appropriate. Furthermore, the "predetermined number" may be set to the same number in the X direction, Y direction, and diagonal direction, or different numbers may be set. In addition, the "predetermined number" may be changed according to the size of the color printing area CPA. For example, if the image is thin line characters, if the number of pixels P excluded from the white printing area WPA is large, the white ink layer WHL, which is the reflective layer, may not be sufficiently formed. In such cases, the contour extraction unit 36 ​​can change the "predetermined number," which is the number of pixels P extracted, to form the white ink layer WHL within an appropriate range. Note that the user may specify the "predetermined number" as a printing condition.

[0087] (ii) The contour extraction unit 36 ​​can extract a predetermined number of pixels P that surround the non-printing area NPA2, specifically those arranged around the outermost pixel P of the non-printing area NPA2. For example, the contour extraction unit 36 ​​can extract a predetermined number of pixels P arranged in the X direction, Y direction, or diagonal direction around the outermost pixel P of the non-printing area NPA2.

[0088] If only the pixels P adjacent to the outermost pixel P of the non-printing area NPA2 are excluded from the color printing area CPA, white ink bleeding may not be adequately reduced. In such cases, white ink bleeding can be adequately reduced by excluding a predetermined number of pixels P aligned with the outermost pixel P of the non-printing area NPA2 from the white printing area WPA. Note that the "predetermined number" is not limited to a specific number and can be set as appropriate. Furthermore, the "predetermined number" may be set to the same number in the X direction, Y direction, and diagonal direction, or different numbers may be set. In addition, the "predetermined number" may be changed according to the size of the color printing area CPA. For example, if the image is thin line characters, if the number of pixels P excluded from the white printing area WPA is large, the white ink layer WHL, which is the reflective layer, may not be formed sufficiently. In such cases, the contour extraction unit 36 ​​can change the "predetermined number," which is the number of pixels P extracted, to form the white ink layer WHL within an appropriate range. Note that the user may specify the "predetermined number" as a printing condition.

[0089] The effects described above can also be applied to the transfer system 1 to which the control device 3 (print data creation device) is applied, the print data creation method executed by the control device 3, and the program that causes the computer to operate as the control device 3.

[0090] <Example 1> The following variations will describe the variations in the processing of the white plate creation unit 34. The configuration of the control device 3 in each modified example is the same as in the embodiment (see Figure 4).

[0091] Figure 9(a) shows the processing modes of the contour extraction unit 36 ​​and the pixel adjustment unit 37 according to Modified Example 1. In Modification 1, the region determination unit 35 determines the color print area CPA and the non-print areas NPA1 and NPA2 in the image data ID, similar to the embodiment (see Figure 7(a)).

[0092] As shown in Figure 9(a), the contour extraction unit 36, similar to the embodiment, extracts pixels P that constitute the contour (pixels P marked with a triangle in the figure) and pixels P that surround the non-printing area NPA2 (pixels P marked with a square in the figure) in the color printing area CPA determined by the area determination unit 35. In Modification 1, the pixel adjustment unit 37 sets the remaining area after excluding the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) from the color printing area CPA (see Figure 7(a)) as the first white ink printing area FPA. In the example in Figure 9, the pixels P marked with ● constitute the first printing area FPA. The first printing area FPA corresponds to the white printing area WPA (see Figure 7(b)) in the embodiment.

[0093] The pixel adjustment unit 37 further sets the area composed of pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) as the second printing area SPA for white ink. In the example in Figure 9, the pixels P marked with a triangle and the pixels P marked with a square constitute the second printing area SPA. The printing density of the white ink in the second printing area SPA is set lower than that of the first printing area FPA. In other words, in the embodiment, pixels P that are excluded from the white printing area WPA are set to pixels that print white ink with a small ejection amount in Modification 1.

[0094] Figure 9(b) shows an example of the settings for white ink density and dot size in the first printing area FPA and the second printing area SPA. As shown in Figure 9(b), the pixel adjustment unit 37 can, for example, set the ejection amount of white ink to be L dot for pixels P that constitute the first printing area FPA. The pixel adjustment unit 37 sets the ejection amount for the second printing area SPA to be less than that for the first printing area FPA. The pixel adjustment unit 37 may set all pixels P in the second printing area SPA to the same ejection amount, or it may set different ejection amounts depending on the position of the pixels P. In the illustrated example, the pixel adjustment unit 37 sets the ejection amount to be lower for pixels P adjacent to non-printing areas NPA1 and NPA2 within the second printing area SPA. Specifically, the pixel adjustment unit 37 sets the ejection amount to be M dot for pixels P in the second printing area SPA that are not directly in contact with non-printing areas NPA1 and NPA2. The pixel adjustment unit 37 sets the ejection amount to be S dot for pixels P adjacent to non-printing areas NPA1 and NPA2 within the second printing area SPA.

[0095] In variation 1, although there are differences in the amount of ink ejected, white ink is printed over the entire surface of the color inks that make up the image. This makes it possible to make the thickness of the printed material more uniform. Furthermore, for example, when an image is composed of small shapes or thin lines of text, the outlines and white areas may occupy a relatively large area within the overall image. In such cases, if no white ink is printed on the outlines or white areas, it may not be possible to secure a sufficient area for the white ink layer (WHL) that acts as the reflective layer. In Modification 1, the outlines and white areas also have a reflective layer formed as the second printing area (SPA), thus improving visibility even in images of small shapes or thin lines of text. As mentioned above, white ink bleeding is more likely to occur when the dot size of the white ink is larger than the pixel P. Therefore, by setting the ejection amount in the second printing area SPA so that the dot size is smaller than that of the first printing area FPA, white ink bleeding can be reduced, similar to the embodiment. Furthermore, within the second printing area SPA, by setting the ejection amount of white ink to a lower level in pixels P adjacent to the non-printing areas NPA1 and NPA2, where bleeding is more likely to occur, it becomes easier to achieve both image visibility and bleeding reduction.

[0096] As described above, the control device 3 of modified example 1 has, for example, the following configuration. (4) The pixel adjustment unit 37 can make the area obtained by excluding the pixels P extracted by the contour extraction unit 36 ​​from the color printing area CPA (the pixels P that constitute the contour of the color printing area CPA and the pixels P that surround the non-printing area NPA2) into the first printing area FPA for white ink. The pixel adjustment unit 37 can make the area composed of pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) into a second printing area SPA for white ink, which is printed with a smaller ejection amount than the first printing area FPA.

[0097] This configuration forms a reflective layer across the entire surface of the color inks that make up the image, thereby improving the visibility of the image. In addition, in areas where image bleeding is likely to occur, such as the outlines and white areas, the dot size of the white ink is reduced as a second printing area SPA, thus reducing bleeding. For example, if an image consists of small shapes or thin lines of text, and white ink is not printed at all on the outlines of the image, the formation of the reflective layer may be insufficient. Therefore, for such images, it is preferable to create print data PD using the method of Modification 1. Furthermore, because white ink is printed over the entire surface of the color inks that make up the image, the thickness of the printed material can be made more uniform.

[0098] (iii) The pixel adjustment unit 37 can set pixels P adjacent to non-printing areas NPA1 and NPA2 in the second printing area SPA to be printed with a smaller ejection amount than other pixels P.

[0099] Within the second printing area (SPA), by further reducing the amount of white ink ejected in pixels P adjacent to the non-printing areas NPA1 and NPA2, where bleeding is more likely to occur, it becomes easier to achieve both image visibility and reduced bleeding.

[0100] <Modification 2> Figure 10 shows the processing method of the pixel adjustment unit 37 according to modified example 2. As shown in Figure 10, in the modified example 2, the pixel adjustment unit 37, similar to the embodiment, sets the remaining area after excluding the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P surrounding the non-printing area NPA2) from the color printing area CPA to the white printing area WPA. The pixel adjustment unit 37 then sets the area composed of pixels P extracted by the contour extraction unit 36 ​​in the color printing area CPA (pixels P that constitute the contour of the color printing area CPA and pixels P that surround the non-printing area NPA2) to be set as the clear printing area CLA, which is printed with clear ink (transparent ink). The pixel adjustment unit 37 may, for example, set the ejection amount of clear ink to be L dot for all pixels P that constitute the clear printing area CLA. Alternatively, as in the first modified example, the ejection amount may be set differently depending on the position of the pixel P. For example, the pixel adjustment unit 37 may set the ink ejection amount to be lower for pixels P adjacent to non-printing areas NPA1 and NPA2 within the clear printing area CLA. The pixel adjustment unit 37 creates white image data WD based on the set white print area WPA, and also creates clear image data CD based on the set clear print area CLA. In Modification 2, the image processing unit 38 (see Figure 4) processes the image data ID and white image data WD, as well as the clear image data CD. As a result, the print data PD created in Modification 2 includes dot data for the color inks CMYK, dot data for the white ink (W), and dot data for the clear ink (CL), as shown in Figure 10.

[0101] In variation 2, clear ink is used instead of white ink for the outlines and white areas of the image. When transferring the image to a dark-colored workpiece (WK), any excess clear ink is less noticeable. Furthermore, because white or clear ink is printed over the entire surface of the color inks that make up the image, the thickness of the printed material can be made more uniform, thus contributing to improved print quality.

[0102] As described above, the control device 3 of modified example 2 has, for example, the following configuration. (5) The pixel adjustment unit 37 creates white image data WD as the white print area WPA (white ink print area) by excluding the pixels P extracted by the contour extraction unit 36 ​​from the color print area CPA (pixels P that constitute the contour of the color print area CPA and pixels P that surround the non-print area NPA2). The pixel adjustment unit 37 creates clear image data CD as the clear print area CLA (clear ink print area) by excluding the area composed of the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color print area CPA and pixels P that surround the non-print area NPA2).

[0103] This configuration makes it less noticeable if the clear ink spills over the image when transferring it to a dark-colored workpiece (WK). Furthermore, because the white or clear ink is printed over the entire surface of the color inks that make up the image, the thickness of the printed material can be made more uniform, contributing to improved print quality.

[0104] <Variation 3> Figure 11 shows the processing method of the pixel adjustment unit 37 according to modified example 3. Modification 3 describes a preferred processing method when the image has a narrow portion NP with a narrow width in the X or Y direction. As shown in Figure 11(a), the pixel adjustment unit 37, similar to the embodiment, can set the remaining area after excluding the pixels P extracted by the contour extraction unit 36 ​​(pixels P that constitute the contour of the color printing area CPA and pixels P surrounding the non-printing area NPA2) from the color printing area CPA to the white printing area WPA. In modified example 3, the pixel adjustment unit 37 determines whether the set white printing area WPA has a narrow section NP. In Figure 11(a), the narrow section NP is shown with double hatching and enclosed by a thick line. The pixel adjustment unit 37 can determine, for example, that the white printing area WPA has a narrow section NP if there is a portion where the number of pixels in the X or Y direction is less than or equal to a predetermined number (for example, 2 pixels). As shown in Figure 11(a), the white print area (WPA) may have a partially narrowed area (NP). Alternatively, if the image consists of small shapes or thin lines of text, the entire white print area (WPA) may be a narrowed area (NP).

[0105] As shown in Figure 11(b), if there is a narrow area NP in the white printing area WPA, the pixel adjustment unit 37 determines which pixels P surround the narrow area NP from among the pixels P excluded from the white printing area WPA (pixels P that constitute the outline of the color printing area CPA and pixels P that surround the non-printing area NPA2). The pixel adjustment unit 37 incorporates at least a portion of the pixels P surrounding the narrow area NP (pixels P marked with a circle in the figure) into the narrow area NP. As a result, the white printing area WPA is expanded to include only the portion of the narrow area NP.

[0106] The pixel adjustment unit 37 performs this process to create white image data WD, so that white ink is printed over the contours of the narrow parts NP of the image. In the narrow area NP of the image, if all pixels P that constitute the contour and pixels P surrounding the non-printed area NPA2 are excluded, the white ink layer WHL may not be sufficiently formed. By performing the process of Modification 3, the white ink layer WHL is properly formed on the narrow area NP, improving the overall visibility of the image. In addition, since pixel adjustment is performed on parts of the image other than the narrow area NP, as in the embodiment, white ink bleeding can be reduced.

[0107] Alternatively, the pixel adjustment unit 37 may set the narrow section NP to an area where white ink is printed with an ejection amount less than the ejection amount set for the white printing area WPA (for example, the ejection amount that results in an L dot). In this case, the dot size of the white ink ejected into the narrow section NP becomes smaller, thus reducing the amount of white ink that spills out. Alternatively, the pixel adjustment unit 37 may be set to print the narrow area NP with clear ink instead of white ink. Clear ink is less noticeable even if it extends beyond the image boundaries. The pixel adjustment unit 37 can perform these operations, for example, when the area occupied by narrow areas NP in the image is large, or when the entire image consists of narrow areas NP, thereby making white ink bleeding less noticeable. The pixel adjustment unit 37 may also perform these operations, for example, when the area occupied by narrow areas NP in the white printing area WPA exceeds a certain percentage. This allows for appropriate printing of white ink according to the shape of the image.

[0108] As described above, the control device 3 of modified example 3 has, for example, the following configuration. (6) The pixel adjustment unit 37 can make the area obtained by excluding the pixels P extracted by the contour extraction unit 36 ​​from the color printing area CPA (the pixels P that constitute the contour of the color printing area CPA and the pixels P that surround the non-printing area NPA2) into the white printing area WPA (the printing area for white ink). The pixel adjustment unit 37 can, if there is a narrow area NP in the white printing area WPA, incorporate at least a portion of the pixels P surrounding the narrow area NP from the excluded area into the narrow area NP.

[0109] With this configuration, white ink is printed in the narrow areas (NP) of the image without excluding the contours. This ensures that the white ink layer (WHL) is properly formed across the entire image, achieving both reduced white ink bleeding and improved image visibility.

[0110] (7) The pixel adjustment unit 37 can make the pixels P constituting the narrow section NP into an area where white ink is printed with a discharge amount less than the discharge amount set for the white printing area WPA, or an area where clear ink is printed.

[0111] By printing white ink in a small amount of ink at the narrow areas of the image (NP), the bleeding of white ink can be reduced. Alternatively, by printing clear ink in the narrow areas of the image (NP), ink bleeding can be made less noticeable. This can improve the quality of printed materials.

[0112] (iv) The pixel adjustment unit 37 can determine that a portion of the white printing area WPA in which the number of pixels in the X direction (one direction) or the Y direction (the other direction perpendicular to the one direction) is less than or equal to a predetermined number is a narrow portion NP. The pixel adjustment unit 37 can, when the area occupied by the narrow portion NP in the white printing area WPA exceeds a certain proportion, configure the pixels P constituting the narrow portion NP to be either an area where white ink is printed with a discharge amount less than the discharge amount set in the white printing area WPA, or an area where clear ink is printed.

[0113] This configuration allows for appropriate printing of white ink according to the shape of the image.

[0114] The present invention is not limited to the embodiments and modifications described above, and can be modified as appropriate within the scope of the technical idea of ​​the present invention. Furthermore, the modifications may not only be applied to the embodiments, but at least a part of the content of each may be applied to other modifications. In addition, the effects described with respect to the transfer method also apply to the transfer system 1 that performs the transfer method and to the method of manufacturing printed materials. [Explanation of Symbols]

[0115] 1. Transfer System 2. Printer (printing device) 3. Control device (print data creation device) 4. Shaker (adhesive application device) 8. Hot press machine (pressing device) 34 White Version Creation Department 35 Area determination section 36 Contour extraction section 37 Pixel adjustment section 38 Image Processing Unit (Dot Data Creation Unit) PD print data M Media ID image data WD White version image data CD Clear Version Image Data P pixels CPA (Cost Per Acquisition) Color Printing Area (Printing area for color inks) NPA1, NPA2 Non-print area WPA White Print Area (Print area for white ink) FPA First Printing Area (First printing area for white ink) SPA Second Printing Area (Second printing area for white ink) CLA Clear Printing Area (Printing area for clear ink) NP narrow part

Claims

1. Print data creation device A print data creation device that creates print data for printing an image onto a medium using a printing device, A dot data creation unit creates dot data indicating the ink ejection position on the media for each ink color used in the printing device, based on image data, as print data. When performing overprinting, which involves printing white ink on top of an image printed with color ink, the system includes an area adjustment unit that adjusts the printing area of ​​the white ink based on the image data. The aforementioned region adjustment unit is A region determination unit for determining the printing area of ​​the color ink shown in the image data, A contour extraction unit that extracts pixels that constitute the contour of the printed area of ​​the color ink, The system includes a pixel adjustment unit that adjusts the printing area of ​​the color ink based on the pixels that constitute the contour, thereby determining the printing area of ​​the white ink. The print data creation apparatus is characterized in that the dot data creation unit creates dot data for the white ink in addition to the dot data for the color ink, based on the image data and the print area of ​​the white ink.

2. In claim 1, The pixel adjustment unit is characterized in that the area obtained by excluding the pixels constituting the contour from the printing area of ​​the color ink is used as the printing area for the white ink.

3. In claim 2, If there is a non-printing area within the color ink printing area where the color ink is not printed, the contour extraction unit extracts pixels surrounding the non-printing area within the color ink printing area. The pixel adjustment unit is characterized in that the area obtained by excluding the pixels constituting the contour and the pixels surrounding the non-printing area from the printing area of ​​the color ink is defined as the printing area for the white ink.

4. Variation 1 In claim 2 or claim 3, The print data creation apparatus is characterized in that the pixel adjustment unit sets the area obtained by excluding the pixels extracted by the contour extraction unit from the print area of ​​the color ink as the first print area of ​​the white ink, and the area composed of the pixels extracted by the contour extraction unit as the second print area of ​​the white ink, which is printed with a smaller ejection amount than the first print area.

5. Variation 2 In claim 2 or 3, The pixel adjustment unit is characterized in that it sets the area obtained by excluding the pixels extracted by the contour extraction unit from the color ink printing area as the white ink printing area, and the area composed of the pixels extracted by the contour extraction unit as the transparent ink printing area.

6. Variation 3 In claim 2 or 3, The pixel adjustment unit sets the area obtained by excluding the pixels extracted by the contour extraction unit from the color ink printing area as the white ink printing area. The pixel adjustment unit is characterized in that, when there is a narrow area in the printing area of ​​the white ink, it incorporates at least a portion of the pixels surrounding the narrow area from the excluded area into the narrow area.

7. Variation 3 In claim 6, The pixel adjustment unit is characterized in that it sets the pixels constituting the narrow portion to either an area where white ink is printed with a discharge amount less than a set discharge amount, or an area where transparent ink is printed.

8. In claim 1, The printing data creation apparatus is characterized in that the white ink is an ink having a light-reflective pigment.

9. In claim 5, The print data creation apparatus is characterized in that the transparent ink is an ink that does not contain pigments or dyes.

10. In claim 7, The print data creation apparatus is characterized in that the transparent ink is an ink that does not contain pigments or dyes.

11. Transfer system A transfer system including a print data creation device as described in claim 1, A printing device that prints the image on the medium using the color ink and prints the white ink over the image based on the print data created by the print data creation device, An adhesive application device for applying adhesive to the white ink printed on the media, A transfer system comprising a press device that transfers the image to which the adhesive has been applied to the workpiece by placing the printed surface of the media on top of the workpiece and pressing it.

12. How to create print data A method for creating print data for printing an image onto a medium using a printing device, Based on image data, a dot data creation process is performed to create dot data indicating the ink ejection position on the media for each ink color used in the printing device, as print data. When performing overprinting, which involves printing white ink on top of an image printed with color ink, the process includes an adjustment process to adjust the printing area of ​​the white ink based on the image data. The adjustment process described above is: A region determination process for determining the printing area of ​​the color ink shown in the image data, A contour extraction process for extracting pixels that constitute the contour of the printed area of ​​the aforementioned color ink, The process includes a pixel adjustment process that adjusts the printing area of ​​the color ink based on the pixels constituting the contour to determine the printing area of ​​the white ink, A method for creating print data, characterized in that, in the dot data creation process, dot data for white ink is created in addition to the dot data for color ink based on the image data and the print area of ​​the white ink.

13. program A program that creates print data for printing an image onto media using a printing device, On the computer, Based on image data, a dot data creation process is performed to create dot data indicating the ink ejection position on the media for each ink color used in the printing device, as print data. When performing overprinting, which involves printing white ink on top of an image printed with color ink, an adjustment process is performed to adjust the printing area of ​​the white ink based on the image data. The adjustment process described above is: A region determination process for determining the printing area of ​​the color ink shown in the image data, A contour extraction process for extracting pixels that constitute the contour of the printed area of ​​the aforementioned color ink, The process includes a pixel adjustment process that adjusts the printing area of ​​the color ink based on the pixels constituting the contour to determine the printing area of ​​the white ink, A program characterized in that, in the dot data creation process, it creates dot data for white ink in addition to the dot data for color ink, based on the image data and the printing area of ​​the white ink.

Images