Printer, control method of the same, and program

Abstract

To provide a printer which can suppress lowering of image quality of an image transferred onto a medium to be transferred.SOLUTION: A printer 10 includes a head 20 discharging ink having sublimability, and a control part 50, where the control part executes: printing processing of discharging ink to a medium to be printed from the head, according to one mode selected from printing modes including at least a first printing mode, and a second printing mode having a smaller used amount of ink than that in the first printing mode on the basis of image data; and first output processing of outputting a second transfer condition having transfer energy to transfer a printed image onto a medium to be transferred from the medium to be printed larger than that of a first transfer condition, out of the first transfer condition, and the second transfer condition, as a transfer condition to transfer the printed image printed onto the medium to be printed by the printing processing to the medium to be transferred when the printing mode is the second printing mode.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a printing apparatus, a control method thereof, and a program.

Background Art

[0002] As a conventional printing apparatus, for example, a control information generation apparatus disclosed in Patent Document 1 below is known. In this control information generation apparatus, heat transfer control information for heating a printed matter printed on a first medium based on image data and heat-transferring it to a second medium is generated. This heat transfer control information includes a transfer temperature and a transfer time as transfer conditions based on the amount of ink used for printing the printed matter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the control information generation apparatus of the above prior art, the larger the amount of ink used for printing the printed matter, the higher the transfer temperature and the longer the transfer time. However, under such transfer conditions, the printed matter in a printing mode with a small amount of ink may not be sufficiently heat-transferred to the second medium, and the image quality of the transferred matter may deteriorate.

[0005] Therefore, an object of the present invention is to provide a printing apparatus, a control method thereof, and a program capable of suppressing deterioration in image quality of an image transferred to a transfer medium.

Means for Solving the Problems

[0006] The printing apparatus according to the present disclosure includes a head that discharges sublimable ink and a control unit. The control unit causes the head to discharge ink onto a medium to be printed according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode, based on image data. When the printing mode is the second printing mode, the control unit executes a first output process of outputting a second transfer condition as a transfer condition for transferring a printed image printed on the medium to be printed to a transfer medium, the second transfer condition being such that the transfer energy for transferring the printed image from the medium to be printed to the transfer medium is greater than a first transfer condition.

[0007] A control method for a printing apparatus according to the present disclosure is a control method for a printing apparatus including a head that discharges sublimable ink. The control method causes the head to discharge ink onto a medium to be printed according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode, based on image data. When the printing mode is the second printing mode, the control method executes a first output process of outputting a second transfer condition as a transfer condition for transferring a printed image printed on the medium to be printed to a transfer medium, the second transfer condition being such that the transfer energy for transferring the printed image from the medium to be printed to the transfer medium is greater than a first transfer condition.

[0008] The program according to the present disclosure causes a printing apparatus including a head that discharges sublimable ink to discharge ink from the head onto a printing medium according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode based on image data, and when the printing mode is the second printing mode, as transfer conditions for transferring a printed image printed on the printing medium by the printing process to a transfer medium, a first transfer condition and a second transfer condition in which transfer energy for transferring the printed image from the printing medium to the transfer medium is greater than the first transfer condition, to execute a first output process of outputting the second transfer condition.

[0009] According to the present disclosure, the printed image formed on the printing medium by the printing process in the second printing mode uses less ink than the first printing mode. On the other hand, the second transfer condition is output as transfer conditions for transferring this printed image to the transfer medium. In this second transfer condition, the transfer energy for transferring the printed image from the printing medium to the transfer medium is greater than the first transfer condition. Therefore, reduction of the ink amount of the printed image when transferred from the printing medium to the transfer medium is suppressed, and deterioration of the image quality of the transferred printed image can be suppressed.

Brief Description of the Drawings

[0010]

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[0011] Hereinafter, embodiments according to the present disclosure will be specifically described with reference to the drawings. In the following, the same or corresponding elements throughout all the drawings will be denoted by the same reference numerals, and redundant explanations will be omitted.

[0012] <Embodiment 1> <Printing Device> As shown in FIG. 1, a printing device 10 according to Embodiment 1 of the present disclosure includes an information processing unit 11 and a printing execution unit 12. The information processing unit 11 processes the image data of a printing image, which is an image to be printed, into a printing format that can be printed by the printing execution unit 12. The printing execution unit 12 prints an image on a printing medium A based on the image data in the printing format.

[0013] <Printing Execution Unit> The printing execution unit 12 is a device that prints an image on the printing medium A based on the image data, and is configured by a printer such as an inkjet printer, for example. The printing execution unit 12 includes a head 20. The head 20 has a plurality of nozzles 21 and a plurality of drive elements 22 (FIG. 2). The drive elements 22 are piezoelectric elements, heating elements, electrostatic actuators, etc., and are provided for each nozzle 21. By driving the drive element 22, ejection energy such as pressure for ejecting ink from the nozzle 21 is applied to the ink in the head 20. As a result, the head 20 ejects ink.

[0014] The plurality of nozzles 21 are arranged in the front-rear direction to form a nozzle row, and the plurality of nozzle rows are arranged in the left-right direction. The nozzle 21 opens on the lower surface of the head 20. The plurality of nozzle rows each eject a plurality of types of ink. For example, the plurality of nozzle rows include a nozzle row of nozzles 21 that eject cyan ink, a nozzle row of nozzles 21 that eject magenta ink, a nozzle row of nozzles 21 that eject yellow ink, and a nozzle row of nozzles 21 that eject black ink. These inks are sublimable inks.

[0015] Hereinafter, the moving direction in which the head 20 moves is referred to as the left-right direction. The direction that intersects (for example, is orthogonal to) this moving direction and in which the printing medium A is conveyed is referred to as the front-rear direction. Also, the direction that intersects (for example, is orthogonal to) the moving direction of the head 20 and the conveying direction of the printing medium A is referred to as the up-down direction. However, the directions related to the printing execution unit 12 are not limited to this.

[0016] Furthermore, the printing execution unit 12 includes a platen 23 and a tank 24. The platen 23 is positioned at a predetermined distance below the head 20. The flat upper surface of the platen 23 is disposed opposite to the lower surface of the head 20 and supports the printing medium A from below. Also, the tank 24 stores ink, communicates with the nozzles 21 of the head 20, and supplies ink to the nozzles 21.

[0017] Furthermore, the printing execution unit 12 includes a moving device 30 that moves the head 20 in the left - right direction. The moving device 30 has a carriage 31, two guide rails 32, an endless belt 33, and a moving motor 34. The carriage 31 is box - shaped and mounts the head 20. The two guide rails 32 extend horizontally across the platen 23 disposed directly below, are arranged front - to - back apart so as to sandwich all the nozzles 21 therebetween, and support the carriage 31 movably. The endless belt 33 is connected to the carriage 31 and is connected to the moving motor 34 via a pulley 35 provided on the guide rail 32. Therefore, when the moving motor 34 is rotationally driven, the endless belt 33 runs, and the carriage 31 and the head 20 mounted on the carriage 31 are moved in the left - right direction along the guide rail 32.

[0018] Furthermore, the printing execution unit 12 includes a conveying device 40 that conveys the printing medium A in the front - rear direction. The conveying device 40 has, for example, conveying rollers 41 and a conveying motor 42 (FIG. 2). The conveying rollers 41 have an axis extending in the left - right direction, and the conveying motor 42 is connected to the axis of the conveying rollers 41. When the conveying motor 42 is rotationally driven, the conveying device 40 rotates the conveying rollers 41 about its axis and conveys the printing medium A in the front - rear direction on the platen 23.

[0019] As shown in FIG. 2, the printing execution unit 12 includes a second control unit 50b, a second communication interface 53b electrically connected to the second control unit 50b, a second display device 57, a head drive circuit 54, a movement drive circuit 55, and a conveyance drive circuit 56. The second display device 57 is a device that displays information such as codes for transfer conditions, for example, a liquid crystal display or the like. Note that the second control unit 50b may be configured by a single device, or a plurality of devices may be distributed and configured to cooperate to perform the operation of the second control unit 50b.

[0020] The second communication interface 53b is a connection device that connects to the information processing unit 11 and may be connected to the information processing unit 11 by wired communication such as a USB cable or wireless communication such as a LAN. The second control unit 50b acquires data such as image data from the information processing unit 11 via the second communication interface 53b. The image data is data representing an image to be printed and is, for example, raster data. Note that the second communication interface 53b may be connected to a device other than the information processing unit 11.

[0021] The second control unit 50b has a second arithmetic unit 51b and a second storage unit 52b. The second storage unit 52b is a memory accessible from the second arithmetic unit 51b and has at least one of, for example, a RAM, a ROM, an E2PROM, and an NVRAM. The second storage unit 52b stores data input from the second communication interface 53b, as well as a computer program and various data used for data processing by the second arithmetic unit 51b.

[0022] The second arithmetic unit 51b is configured by, for example, a computer and includes a circuit such as a processor such as a CPU, an integrated circuit such as an ASIC, or both. By the second arithmetic unit 51b executing a computer program while referring to the stored data in the second storage unit 52b, the second control unit 50b controls the operations of each part of the printing execution unit 12. Thereby, the printing execution unit 12 executes various processes such as a printing process for printing an image.

[0023] The head drive circuit 54 is electrically connected to the drive element 22 of the head 20. The second control unit 50b generates a control signal for driving the drive element 22 based on image data or the like, and the head drive circuit 54 generates a drive signal for the drive element 22 based on this control signal. Then, the drive element 22 is driven based on the drive signal so as to apply ejection energy to the ink in the head 20 at the ejection timing based on the image data. As a result, ink droplets are ejected from the nozzles 21 of the head 20.

[0024] The movement drive circuit 55 is electrically connected to the movement motor 34 of the movement device 30. The second control unit 50b generates a control signal for driving the movement motor 34 based on image data or the like, and the movement drive circuit 55 generates a drive signal for the movement motor 34 based on this control signal. Then, the movement motor 34 is driven based on the drive signal so as to move the carriage 31 on which the head 20 is mounted in the left - right direction at a variable speed and stop the carriage 31 at an arbitrary position within its movable range.

[0025] The conveyance drive circuit 56 is electrically connected to the conveyance motor 42 of the conveyance device 40. The second control unit 50b generates a control signal for driving the conveyance motor 42 based on image data or the like, and the conveyance drive circuit 56 generates a drive signal for the conveyance motor 42 based on this control signal. Then, the conveyance motor 42 is driven based on the drive signal so as to intermittently or continuously convey the printing medium A on the platen 23 in the front - rear direction and stop the printing medium A at a predetermined position on the platen 23.

[0026] <Information processing unit> The information processing unit 11 is a device that processes data such as image data of a printed image that the printing execution unit 12 prints, and is configured by a computer such as a personal computer, a tablet, and a smartphone. The information processing unit 11 includes a first control unit 50a, a first communication interface 53a connected to the first control unit 50a, a first display device 13, and an input device 14.

[0027] The first control unit 50a includes a first arithmetic unit 51a and a first storage unit 52a. The first storage unit 52a is a memory accessible from the first arithmetic unit 51a and has, for example, a RAM and a ROM. Among these, the RAM temporarily stores image data and various data during the operation of the first arithmetic unit 51a. The ROM stores computer programs and data for performing various data processes.

[0028] The first arithmetic unit 51a is composed of, for example, a computer and includes circuits such as a processor like a CPU. The first arithmetic unit 51a controls the operation of the information processing unit 11 by referring to the data stored in the first storage unit 52a and executing a computer program. The first control unit 50a, in cooperation with the second control unit 50b of the printing execution unit 12, constitutes the control unit 50 of the printing apparatus 10 and controls the operation of the printing apparatus 10. Note that the first control unit 50a may be constituted by a single device, or a plurality of devices may be distributed and configured to cooperate to perform the operation of the first control unit 50a.

[0029] The first communication interface 53a is a connection device that connects to external devices existing independently of the printing execution unit 12 and the printing apparatus 10, and may be connected to external devices by wired communication such as a USB cable or wireless communication such as a LAN. Examples of external devices include a computer, a portable terminal device, a server, a storage medium, and a camera. Thereby, the first control unit 50a transmits and receives data such as image data from the printing execution unit 12 and external devices via the first communication interface 53a.

[0030] The first display device 13 is a device that displays information such as the printing mode of the printed image and codes of transfer conditions, for example, a liquid crystal display. The input device 14 is a device that receives input of external information, such as a touch panel, a physical switch, and the first communication interface 53a. The input device 14 receives an operation by the user and transmits the received operation information to the first control unit 50a.

[0031] <Conversion Process of Image Data> When the printing apparatus 10 performs printing processing, the first control unit 50a of the information processing unit 11 performs a conversion process on the image data of the printing image that is the target of the printing process, and transmits the image data in the printing format to the printing execution unit 12. The conversion process includes, for example, color conversion processing and halftone processing.

[0032] In the color conversion process, the first control unit 50a uses a predetermined color conversion look-up table to convert the color values of the image data into color values printable by the printing execution unit 12. For example, the color components of the image data are converted from RGB values to CMYK values. The RGB values are the respective color values of red, green, and blue expressed in 256 gradations from 0 to 255. The CMYK values are color values printable by the ink that can be ejected from the head 20, and are the respective color values of cyan, magenta, yellow, and black expressed in 101 gradations from 0 to 100.

[0033] In the halftone process, the first control unit 50a converts each color value of the CMYK values of the image data into a dot type. The types of these dots include "no dot" where no dot is formed, "small dot", "medium dot" with a size larger than the small dot, and "large dot" with a size larger than the medium dot.

[0034] <Printing Process> In this way, the first control unit 50a transmits the converted image data to the second control unit 50b. The second control unit 50b executes printing processing based on the image data. In this printing process, the second control unit 50b executes a pass operation of ejecting ink from the nozzles 21 of the head 20 onto the printing medium A while moving the head 20 along the left-right direction based on a partial image data of a part of the image data. By this pass operation, the partial image F (FIG. 15) is printed on the printing medium A. Then, the second control unit 50b executes a conveyance operation of conveying the printing medium A along the front-rear direction. By executing this pass operation and conveyance operation, a plurality of partial images F are formed in the front-rear direction, and a printing image composed of the plurality of partial images F is printed on the printing medium A.

[0035] As shown in FIG. 3A, this printed image is a reversed image B which is an image obtained by reversing the front and back of the transferred image C (FIG. 4B). The transferred image C is an image to be transferred onto the medium to be transferred E. Note that the medium A on which the printed image is printed is a heat-resistant sheet, such as a sheet made of a fluororesin, or a sheet obtained by fluororesin-coating paper. As the medium to be transferred E, for example, a fabric such as a T-shirt or paper is used.

[0036] <Transfer process> Thus, the reversed image B is printed on the medium A to be printed with sublimable ink by the printing apparatus 10. Then, as shown in FIG. 3B, the user places the reversed image B on the medium A to be printed so as to face the medium E to be transferred, and as shown in FIG. 4A, overlays the medium A to be printed on the medium E to be transferred. Then, with at least one of the pair of heating plates 61 of the transfer apparatus 60 being heated, the user sandwiches the medium E to be transferred with the medium A to be printed thereon between the pair of heating plates 61, and heats and presses the medium A to be printed. As a result, as shown in FIG. 4B, the sublimable ink of the reversed image B on the medium A to be printed sublimes, and the transferred image C, which is an image obtained by reversing the reversed image B, is transferred onto the medium E to be transferred. Then, the user removes the medium A to be printed from the medium E to be transferred.

[0037] <Printing mode and transfer conditions> As described above, the reversed image B is printed on the medium A to be printed as a printed image by the printing process. This printing mode has, for example, a first printing mode and a second printing mode. The second printing mode is a printing mode in which the amount of ink used for printing the reversed image B is less than that in the first printing mode. The so-called first printing mode is the standard mode, and the second printing mode is the ink save mode. The amount of ink used for forming the reversed image B in the printing process of the second printing mode is less than the amount of ink used in the printing process of the first printing mode for forming the reversed image B of the same size. The amount of ink used may be, for example, the amount of ink for forming the reversed image B with respect to the area of the reversed image B.

[0038] When the printing mode is the second printing mode, the first control unit 50a executes a usage reduction process so that the amount of ink used in the printing process of the second printing mode is less than that of the first printing mode. As a result, the inverted image B is printed with an amount of ink less than that of the first printing mode by the printing process of the second printing mode. The usage reduction process will be described later.

[0039] The transfer conditions are stored in the first storage unit 52a in advance in association with the printing mode so as to suppress a deterioration in the image quality of the transferred image C when the inverted image B printed in this second printing mode is transferred to the transfer medium E. These transfer conditions are conditions for transferring the printed image printed on the print medium A by the printing process to the transfer medium E, and have, for example, a heating temperature, a heating time, and a pressure. Here, the first transfer condition corresponds to the first printing mode, and the second transfer condition corresponds to the second printing mode.

[0040] The second transfer condition has a larger transfer energy for transferring the printed image from the print medium A to the transfer medium E than the first transfer condition. As shown in FIG. 4A, this transfer energy is applied to the inverted image B on the print medium A when the print medium A and the transfer medium E are heated and pressed between a pair of heating plates 61. For example, the transfer energy is determined by this heating time, heating temperature, and the pressure of the pressing. The transfer energy increases as the pressing time is longer, the heating temperature is higher, and the pressure of the pressing is higher. Since at least one of the heating time, heating temperature, and pressure of the pressing of the second transfer condition is different from the first transfer condition, the transfer energy of the second transfer condition is larger than the first transfer condition.

[0041] In the second printing mode, the amount of ink used to form the inverted image B is less than that in the first printing mode. Even in such a case, by using the second transfer condition with a large transfer energy as the transfer condition for the inverted image B, a decrease in the amount of ink of the inverted image B when being transferred from the print medium A to the transfer medium E is suppressed more than the first transfer condition. Therefore, a reduction in the image quality of the transferred image C onto which the inverted image B is transferred can be suppressed.

[0042] <Reduced Usage Processing> For example, reduced usage processing is performed using a tone curve so that the ink usage in the second printing mode is less than that in the first printing mode. As shown in FIG. 5, this tone curve defines the correspondence between input values taking RGB values from 0 to 255 and output values, and is pre-stored in the first storage unit 52a. The dashed line in FIG. 5 indicates that the output value is the same as the input value, and the ink usage is not reduced.

[0043] On the other hand, the tone curve shown by the solid line in FIG. 5 has an output value that is the same as or greater than the input value, and among these output values, there are more values greater than the input value than the value that is the same as the input value. Using this tone curve, with the RGB value of each pixel of the image data as the input value, reduced usage processing is performed. As a result, the RGB value of each pixel of the image data has the output value of the tone curve and indicates a value equal to or greater than the input value. As a result, since the density of the printed image after the reduced usage processing becomes overall lower, the ink usage of the printed image is reduced.

[0044] Note that the reduced usage processing is not limited to the method using a tone curve. For example, the first control unit 50a may perform halftone processing on the image data so that the dot size of the image data for the second printing mode is smaller than that in the first printing mode. Further, after performing the same halftone processing as in the first printing mode on the image data, the first control unit 50a may perform correction processing such that the dot size is reduced or the number of dots is decreased in the image data. By performing the printing process based on such image data for the second printing mode, the ink usage of the printed image is reduced.

[0045] <Transfer Device> As shown in FIG. 4A, the transfer device 60 includes a pair of heating plates 61 and a controller 62. As described above, the pair of heating plates 61 sandwich the printed medium A on which the inverted image B is printed and the transfer medium E therebetween, heat and press the inverted image B, and transfer the inverted image B from the printed medium A to the transfer medium E.

[0046] The controller 62 is composed of a computer such as a mobile terminal device and a personal computer, can communicate via a communication interface by wireless or wired means, and is provided with input devices such as a touch panel 63 and a camera 64. Further, the controller 62 includes an arithmetic unit composed of a processor such as a CPU, and a storage unit composed of a memory such as a RAM and a ROM. By executing the program stored in the storage unit by this arithmetic unit, the controller 62 controls the operation of the transfer device 60.

[0047] <First Output Process> The printing device 10 executes a first output process of outputting a first transfer condition or a second transfer condition as a transfer condition for transferring a printed image. When the transfer condition corresponding to the printing mode for printing the inverted image B which is the printed image is output by the printing device 10, the controller 62 of the transfer device 60 acquires the transfer condition. For example, the printing device 10 prints (outputs) the code D of the transfer condition together with the inverted image B on the print medium A. On the other hand, the transfer device 60 reads the code D printed on the print medium A by the camera 64, the controller 62 acquires the transfer condition corresponding to the code D, and controls the transfer device 60 according to the transfer condition.

[0048] This code D is obtained by coding the first transfer condition and the second transfer condition as transfer conditions according to a predetermined rule, and the image data thereof is stored in the first storage unit 52a. As the code D, for example, a two-dimensional code such as a matrix code, and a one-dimensional code such as a bar code are used. Note that the code D may be printed with a predetermined amount of ink regardless of the printing mode in which the inverted image B is printed.

[0049] Note that the output of the transfer condition is not limited to the printing of the code D. For example, the printing device 10 may display (output) the code D of the transfer condition corresponding to the printing mode on at least one of the first display device 13 and the second display device 57. In this case, the transfer device 60 may read the code D by the camera 64, and the controller 62 may acquire the transfer condition corresponding to the code D.

[0050] Further, the printing apparatus 10 may transmit (output) transfer conditions corresponding to the printing mode via the first communication interface 53a. In this case, the transfer apparatus 60 may receive the transfer conditions via the communication interface, and the controller 62 may acquire the transfer conditions from the communication interface.

[0051] Further, the printing apparatus 10 may display (output) transfer conditions corresponding to the printing mode on at least one of the first display device 13 and the second display device 57. Further, the printing apparatus 10 may print (output) transfer conditions corresponding to the printing mode on the printing medium A. The transfer conditions include at least one of a heating temperature, a heating time, and a pressure. In this case, the user may view the transfer conditions and input the transfer conditions to the controller 62 via an input device 14 such as the touch panel 63 of the transfer apparatus 60.

[0052] As described above, the transfer apparatus 60 is controlled by the controller 62 according to the transfer conditions. Thereby, the reverse image B is heated and pressurized by the heating plate 61 at the pressure, heating temperature, and heating time according to the transfer conditions, and is transferred to the transfer medium E.

[0053] On the other hand, the code D of the transfer conditions is not transferred to the transfer medium E. For example, since the code D is not heated and pressurized by the heating plate 61, the code D may not be transferred. Further, the code D may not be transferred by being printed with ink that is not transferred even when heated and pressurized. Further, the code D may not be transferred by being printed on the back surface of the printing medium A, which is opposite to the surface on which the reverse image B is printed.

[0054] <Control Method of Printing Apparatus> The printing device 10 is controlled by a first control unit 50a and a second control unit 50b as a control unit 50, for example, in accordance with the flowchart of FIG. 6. For example, the printing device 10 starts the processing of FIG. 6 in accordance with a start instruction from the user using the input device 14. In the processing of FIG. 6, the first control unit 50a acquires image data of the inverted image B to be printed from the first communication interface 53a, the first storage unit 52a, etc. (step S10).

[0055] Also, the first control unit 50a acquires a printing mode when printing the inverted image B (step S11). For example, as options for the printing mode, the first control unit 50a displays a first printing mode and a second printing mode on the first display device 13. On the other hand, when the user selects the first printing mode or the second printing mode as the printing mode of the inverted image B using the input device 14, the selected printing mode is input to the first control unit 50a by the input device 14. Thereby, the first control unit 50a acquires the printing mode from the input device 14.

[0056] Then, the first control unit 50a executes a first determination process to determine whether this printing mode is the second printing mode (step S12). If the printing mode is the second printing mode in the first determination process (step S12: YES), the first control unit 50a executes a usage reduction process. In the usage reduction process, the first control unit 50a generates image data for the second printing mode from the image data acquired in step S10 so that the ink usage amount is smaller than that in the first printing mode (step S13). Then, the first control unit 50a performs a conversion process on the image data to generate image data in a printing format and transmits it to the second control unit 50b.

[0057] The second control unit 50b executes a printing process based on the image data for the second printing mode (step S14). The inverted image B is printed by the printing process of this second printing mode, and the ink usage amount used for this inverted image B is less than that in printing in the first printing mode.

[0058] Further, the first control unit 50a executes first output processing and outputs, as transfer conditions, second transfer conditions corresponding to the second printing mode (step S15). Here, the first control unit 50a transmits the image data of the code D of the second transfer conditions to the second control unit 50b, and the second control unit 50b prints (outputs) the code D on the printing medium A based on the image data.

[0059] In this way, the reverse image B and the code D of the second transfer conditions are printed on the printing medium A. When the user causes the camera 64 of the transfer device 60 to read this code D, the code D is input to the controller 62. The controller 62 controls the transfer device 60 according to the second transfer conditions corresponding to the code D. Then, the user places the printing medium A and the transfer medium E between a pair of heating plates 61. As a result, the printing medium A and the transfer medium E are heated and pressurized by the pair of heating plates 61 according to the heating temperature, heating time, and pressure of the second transfer conditions, and the reverse image B on the printing medium A is transferred to the transfer medium E. This second transfer condition has a larger transfer energy than the first transfer condition. Therefore, even for the reverse image B in the second printing mode with a smaller ink amount than in the first printing mode, a decrease in the ink amount due to transfer can be suppressed, and a deterioration in the image quality of the transferred image C transferred to the transfer medium E can be suppressed.

[0060] Also, when the printing mode is the first printing mode in the first determination process of step S12 (step S12: NO), the first control unit 50a generates the image data acquired in step S10 as the image data for the first printing mode without executing the usage reduction process. Then, the first control unit 50a performs conversion processing on the image data and transmits the image data for the first printing mode in the form of printing to the second control unit 50b. The second control unit 50b executes printing processing in the first printing mode based on this image data (step S16). The amount of ink used for printing the reverse image B printed by this printing processing is larger than that in printing in the second printing mode.

[0061] Further, the first control unit 50a executes first output processing and outputs the first transfer condition corresponding to the first printing mode as the transfer condition (step S17). Here, the first control unit 50a transmits the image data of the code D of the first transfer condition to the second control unit 50b, and the second control unit 50b prints (outputs) the code D on the printing medium A based on the image data.

[0062] In this way, the reverse image B and the code D of the first transfer condition are printed on the printing medium A. When the user reads the code D with the camera 64 of the transfer device 60, the code D is input to the controller 62. The controller 62 controls the transfer device 60 according to the first transfer condition corresponding to the code D. Then, the user places the printing medium A and the transfer medium E between the pair of heating plates 61. As a result, the printing medium A and the transfer medium E are heated and pressurized by the pair of heating plates 61 according to the heating temperature, heating time, and pressure of the first transfer condition, and the reverse image B on the printing medium A is transferred to the transfer medium E. Since this transfer energy is small, the transfer cost can be reduced.

[0063] <Modification Example 1> In the printing apparatus 10 according to Modification Example 1, in the first embodiment, the control unit 50 executes a characteristic determination process for determining whether or not the transfer medium E has heat resistance. Then, when the transfer medium E does not have heat resistance in the characteristic determination process, the control unit 50 outputs the first transfer condition as the transfer condition in the first output process.

[0064] Specifically, the printing apparatus 10 according to Modification Example 1 is controlled by the first control unit 50a and the second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 7. In FIG. 7, in addition to steps S10 to S17 in FIG. 6, a characteristic determination process of step S18 is executed between step S12 and step S13.

[0065] That is, the first control unit 50a acquires the image data of the inverted image B and the printing mode (steps S10, S11). Then, when the printing mode is the second printing mode (step S12: YES), the first control unit 50a executes a characteristic determination process to determine whether the transfer medium E has heat resistance (step S18).

[0066] For example, the first control unit 50a displays options for the material of the transfer medium E on the first display device 13. Examples of such materials include cotton, hemp, polyester, and rayon. In contrast, when the user uses the input device 14 to select the material of the transfer medium E onto which the inverted image B is to be transferred from the options, the selected material is input to the first control unit 50a by the input device 14. The association between this material and the presence or absence of heat resistance is stored in advance in the first storage unit 52a. Therefore, the first control unit 50a determines the presence or absence of heat resistance of the transfer medium E based on the heat resistance corresponding to the material.

[0067] Here, when the transfer medium E has heat resistance (step S18: YES), the first control unit 50a executes a usage reduction process (step S13), and the second control unit 50b executes a printing process in the second printing mode (step S14). Also, the first control unit 50a executes a first output process, transmits the second transfer condition corresponding to the second printing mode to the second control unit 50b, and the second control unit 50b prints (outputs) the code D of the second transfer condition on the print medium A in the first output process (step S15). As a result, since the transfer medium E having heat resistance is less likely to deteriorate by transfer, by increasing the transfer energy in the second transfer condition transfer, a decrease in the ink amount of the inverted image B due to transfer can be suppressed, and a decrease in the image quality of the transferred image C transferred to the transfer medium E can be suppressed.

[0068] When the printing mode is the first printing mode in step S12 (step S12: NO), and when the transfer medium E does not have heat resistance in step S18 (step S18: NO), the first control unit 50a executes the printing process in the first printing mode (step S16). Further, the first control unit 50a executes the first output process, transmits the first transfer condition corresponding to the first printing mode to the second control unit 50b, and the second control unit 50b prints (outputs) the code D of the first transfer condition on the printing medium A in the first output process (step S17). Thus, since the transfer medium E having no heat resistance is likely to deteriorate by transfer, by reducing the transfer energy of the first transfer condition, it is possible to suppress a decrease in the image quality of the transferred image C due to the deterioration of the transfer medium E. Also, since the transfer energy is small, it is possible to reduce the transfer cost.

[0069] <Modification Example 2> In the printing apparatus 10 according to Modification Example 2, in the first embodiment and Modification Example 1, the printing mode of the printing process is a mode different from the first printing mode and the second printing mode and has a third printing mode for forming a thin-line printed image. The transfer condition has a third transfer condition with a transfer energy smaller than that of the first transfer condition. The control unit 50 executes a second determination process for determining whether or not the printing mode is the third printing mode, and a second output process for outputting the third transfer condition as the transfer condition when the printing mode is the third printing mode in the second determination process.

[0070] Specifically, the printing mode has a third printing mode in addition to the first printing mode and the second printing mode. The third printing mode is a printing mode more suitable for printing thin lines than the first printing mode and the second printing mode. The thin line is, for example, a line image in which the width of the line in a direction orthogonal to the direction in which the line extends is a predetermined value or less, or a line image in which the dimension of the line in a direction orthogonal to the direction in which the line extends is a predetermined value or less with respect to the dimension of the line in the direction in which the line extends.

[0071] Note that, for the third printing mode, the amount of ink used for printing the inverted image B, which is a printed image of a thin line, may be less than that in the second printing mode. In this case, the first control unit 50a may execute a usage amount reduction process so that the amount of ink used in the printing process of the third printing mode is less than that in the second printing mode.

[0072] This third printing mode is stored in the first storage unit 52a in advance in association with the third transfer condition. This third transfer condition is a transfer condition in which the transfer energy for transferring the printed image from the printing medium A to the transfer medium E is smaller than the first transfer condition. Since at least one of the heating time, heating temperature, and pressure of pressing in the third transfer condition is different from the first transfer condition, the transfer energy of the third transfer condition is smaller than the first transfer condition. Therefore, the transfer energy becomes smaller in the order of the second printing mode, the first printing mode, and the third printing mode.

[0073] Transfer energy smaller than the first transfer condition according to the third transfer condition is applied to the inverted image B of the thin line printed in the third printing mode. As a result, when transferred under the third transfer condition, the amount of ink of the inverted image B transferred from the printing medium A to the transfer medium E can be suppressed to be less than that under the first transfer condition. Therefore, it is difficult for the line to become thick due to transfer, and it is possible to suppress a reduction in image quality due to the line becoming thick.

[0074] The printing apparatus 10 according to this modification example 2 is controlled by the first control unit 50a and the second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 8. In FIG. 8, in addition to the processes of steps S10 to S17 in FIG. 6, the second determination process and the second output process of steps S18 to S20 are executed after step S12: NO.

[0075] That is, the first control unit 50a acquires the image data of the inverted image B and its printing mode (steps S10, S11). When the printing mode is the second printing mode (step S12: YES), the first control unit 50a executes a usage reduction process (step S13). The second control unit 50b executes a printing process in the second printing mode (step S14) and prints (outputs) the code D of the second transfer condition (step S15).

[0076] Also, when the printing mode is not the second printing mode in step S12 (step S12: NO), the first control unit 50a executes a second determination process to determine whether the printing mode is the third printing mode (step S19). When the printing mode is the first printing mode in the second determination process of step S19 (step S19: NO), the first control unit 50a executes a printing process in the first printing mode (step S16). Further, the first control unit 50a executes a first output process, transmits the first transfer condition corresponding to the first printing mode to the second control unit 50b, and the second control unit 50b prints (outputs) the code D of the first transfer condition on the print medium A (step S17). Since the transfer energy of this first transfer condition is small, the transfer cost can be reduced.

[0077] When the printing mode is the third printing mode in the second determination process of step S19 (step S19: YES), the first control unit 50a executes a usage reduction process on the image data acquired in step S10. By this usage reduction process, the ink usage in the third printing mode is less than that in the second printing mode. Further, the first control unit 50a executes a conversion process on the image data, generates image data in a printing format, and transmits it to the second control unit 50b. The second control unit 50b executes a printing process in the third printing mode based on this image data (step S20). Thereby, the ink usage for printing the inverted image B with thin lines is less than that in printing in the second printing mode.

[0078] Further, the first control unit 50a executes second output processing and transmits image data of code D of the third transfer condition corresponding to the third printing mode to the second control unit 50b. The second control unit 50b prints (outputs) code D on the printing medium A based on this image data (step S21).

[0079] By causing the camera 64 of the transfer device 60 to read the code D of this third transfer condition, the third transfer condition is input to the controller 62, and the transfer device 60 is controlled by the controller 62 according to the third transfer condition. As a result, the printing medium A and the transfer medium E are heated and pressurized by the heating plate 61 of the transfer device 60, and the reverse image B on the printing medium A is transferred to the transfer medium E. Transfer energy smaller than the first transfer condition is applied to the thin-line reverse image B according to this third transfer condition. Thereby, the ink amount of the transferred reverse image B can be suppressed to be less than that in the first transfer condition, and a reduction in image quality due to the line becoming thick can be suppressed.

[0080] <Embodiment 2> In the printing apparatus 10 according to Embodiment 2, in Embodiment 1 and Modification Examples 1-2, when the printing mode is the second printing mode in the first determination process, the control unit 50 executes bidirectional printing processing in which ink is discharged from the head 20 in the forward and return paths of the moving direction. When the printing mode is not the second printing mode in the first determination process, the control unit 50 executes unidirectional printing processing in which ink is discharged from the head 20 in the forward or return path of the moving direction.

[0081] Specifically, in the bidirectional printing process, a pass operation of discharging ink while moving the head 20 and a conveyance operation of the printing medium A are alternately executed. For this reason, in a plurality of pass operations in the bidirectional printing process, a forward pass operation of discharging ink from the head 20 in the forward path in which the head 20 moves in one direction in the left-right direction and a return pass operation of discharging ink from the head 20 in the return path in which the head 20 moves in the other direction in the left-right direction are alternately executed.

[0082] Thus, in the bidirectional printing process, the moving directions of the head 20 in the left - right direction during the forward path operation and the return path operation are different from each other. In contrast, the nozzle rows are arranged in the left - right direction, and in accordance with this arrangement order, cyan ink, magenta ink, yellow ink, and black ink are ejected from the nozzles 21 of the nozzle rows. As a result, the stacking order of the ink ejected from the nozzles 21 is different between the forward path operation and the return path operation. Therefore, even if the types and amounts of the stacked ink are the same between these path operations, a color difference may occur between them. Hereinafter, this color difference is referred to as the color difference between directions.

[0083] In contrast, in the unidirectional printing process, in addition to the path operation of ejecting ink while moving the head 20 and the conveyance operation of the printing medium A, a moving operation of moving the head 20 without ejecting ink is executed. In a plurality of path operations in this unidirectional printing process, a path operation of ejecting ink from the head 20 is continuously executed on the forward path where the head 20 moves in one direction in the left - right direction. Therefore, on the return path where the head 20 moves in the other direction in the left - right direction, the moving operation is executed without ejecting ink from the head 20.

[0084] Thus, in the unidirectional printing process, the moving directions of the head 20 in the left - right direction are the same in a plurality of path operations. Therefore, the stacking order of the ink ejected from the nozzles 21 is the same in a plurality of path operations, and the color difference between directions of the partial image F formed by the path operations does not occur.

[0085] Also, in the second printing mode, the amount of ink used to form the partial image F by the path operation is less than that in the first printing mode. Therefore, the color difference between directions between the forward path operation and the return path operation is less likely to occur in the second printing mode than in the first printing mode. Therefore, the bidirectional printing process is executed in the second printing mode, and the unidirectional printing process is executed in the first printing mode.

[0086] <Control Method of Printing Device> The printing apparatus 10 according to Embodiment 2 is controlled by a first control unit 50a and a second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 9. In the flowchart of FIG. 9, in addition to the processes of steps S10 to S17 in FIG. 6, the process of step S22 between step S12 and step S14 and the process of step S23 between step S12 and step S16 are executed.

[0087] That is, the first control unit 50a acquires the image data of the inverted image B and the printing mode of its printing process (steps S10, S11). When the printing mode is the second printing mode (step S12: YES), the first control unit 50a determines the moving direction of the head 20 in the plurality of pass operations in the printing process to be bidirectional, both left and right (step S22), executes the usage limit process (step S13), and the second control unit 50b executes the bidirectional printing process in the second printing mode (step S14).

[0088] By this bidirectional printing process, since the head 20 moves in both the left and right directions while discharging ink, the speed of the printing process can be increased. In addition, since the amount of ink forming the printed inverted image B is small, the color of the image printed in the second printing mode is lighter than that in the first printing mode. Therefore, the color difference between directions between the partial images F formed by the plurality of pass operations is suppressed, and the reduction in image quality due to this color difference between directions is suppressed.

[0089] Further, the first control unit 50a outputs the second transfer condition corresponding to the second printing mode as the transfer condition (step S15). According to this second transfer condition, the transfer device 60 transfers the inverted image B from the printing medium A to the transfer medium E. Since the color difference between directions of this inverted image B is suppressed, it is possible to suppress a decrease in image quality due to the color difference between directions in the transferred image C to which the inverted image B is transferred.

[0090] When the printing mode is the first printing mode in step S12 (step S12: NO), the first control unit 50a determines the moving direction of the head 20 in a plurality of pass operations in the printing process to be one of left and right, i.e., a single direction (step S23), and the second control unit 50b executes a two-way printing process in the first printing mode (step S16). The moving direction in this pass operation is a predetermined direction. For example, ink is ejected in the forward pass, and no ink is ejected in the return pass. As a result, since the overlapping manner of a plurality of types of ink is the same in a plurality of pass operations, no directional color difference occurs between partial images F formed by the plurality of pass operations.

[0091] Also, the first control unit 50a outputs the first transfer condition corresponding to the first printing mode as the transfer condition (step S15). According to this first transfer condition, the transfer device 60 transfers the inverted image B from the printing medium A to the transfer medium E. Since no directional color difference occurs in this inverted image B, it is possible to suppress a decrease in image quality due to the directional color difference in the transferred image C to which the inverted image B is transferred.

[0092] <Modification Example 3> In the above-described second embodiment, in the one-way printing process in the first printing mode, all partial images F in the printed image are formed by the forward pass operation. However, a partial image F with a small directional color difference may be formed by the return pass operation. Therefore, in Modification Example 3, when the printing mode is not the second printing mode in the first determination process, the control unit 50 executes a direction determination process of determining whether to eject ink from the head 20 in the forward pass or the return pass of the moving direction based on the color difference between the image in which ink is ejected from the head 20 in the forward pass of the moving direction and the image in which ink is ejected from the head 20 in the return pass of the moving direction.

[0093] The printing apparatus 10 according to Modification 3 is controlled by a first control unit 50a and a second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 10. In FIG. 10, instead of step S23 in FIG. 9, the direction determination process of step S24 is executed. In the direction determination process, the first control unit 50a acquires the color value of each of a plurality of pixels in the partial image data targeted for the pass operation. Examples of this color value include RGB values and CMYK values.

[0094] Then, the first control unit 50a acquires an index value from the color value of the pixel based on the index table. This index table is a table that associates a color value with the index value of that color value, and is stored in advance in the first storage unit 52a. The index value is the degree of the color difference between directions of the color value, and represents the color difference between the case where the image of that color value is formed by the forward pass operation and the case where it is formed by the return pass operation.

[0095] Then, the first control unit 50a acquires the index values of a plurality of pixels constituting the partial image F based on the partial image data, and calculates the average value of the plurality of index values as the evaluation value of the partial image F. This evaluation value is the degree of the color difference between directions of the partial image F, and represents the color difference between the case where the partial image F is formed by the forward pass operation and the case where it is formed by the return pass operation.

[0096] When the evaluation value of the partial image F is equal to or greater than a predetermined value, the color difference between directions of the partial image F is large. In this case, the partial image F is formed by the forward pass operation in a predetermined direction. On the other hand, when the evaluation value of the partial image F is less than the predetermined value, the color difference between directions of the partial image F is small. In this case, even if this partial image F is formed by the return pass operation in the direction opposite to the predetermined direction, the color difference between directions is difficult to stand out. Therefore, this partial image F is formed by the return pass operation.

[0097] As described above, in the printing process of the first printing mode, the plurality of partial images F that make up the printed image are basically formed by the path movement in a predetermined direction (e.g., the forward path). However, even if the partial image F with a small color difference between directions is formed by the path movement in the direction opposite to the predetermined direction (e.g., the return path), the color difference from the other partial images F formed by the path movement in the forward path is not easily noticeable. Therefore, the partial image F with a small color difference between directions is formed by the path movement in the return path. Since this path movement in the return path is executed instead of the movement operation of the head 20, it is possible to increase the speed of the printing process while suppressing the deterioration of the image quality caused by the color difference between directions.

[0098] <Embodiment 3> In the printing apparatus 10 according to Embodiment 3, in Embodiments 1-2 and Modification Examples 1-3, the head 20 discharges a plurality of types of color inks including two or more types of color inks that can express black by mixing colors, namely, the first nozzles 21a, and the second nozzles 21b that discharge black ink. The control unit 50 executes a pixel acquisition process of acquiring dark pixels among the pixels of the printed image based on the image data, where the color value is closer to black than the first predetermined color value. When the printing mode is the second printing mode in the first determination process, the control unit 50 executes a color substitution process of using black ink instead of mixing a plurality of types of color inks to form dark pixels in the printing process.

[0099] Specifically, as shown in FIG. 1, the plurality of nozzles 21 include the first nozzles 21a and the second nozzles 21b. The second nozzles 21b discharge black ink. The first nozzles 21a discharge color inks, and the color inks include, for example, cyan ink, magenta ink, and yellow ink. When these cyan ink, magenta ink, and yellow ink overlap in equal amounts, these inks are mixed to express black. Therefore, in the color substitution process, for dark pixels containing black as a color component, single-color black by black ink is used instead of the mixed-color black by cyan ink, magenta ink, and yellow ink.

[0100] As shown in FIG. 11, the color gamut of the RGB color space of the printing apparatus 10 is represented by a three-dimensional orthogonal coordinate system and has a cubic shape. This color gamut has eight vertices. These vertices are the black vertex Vk(0, 0, 0), the red vertex Vr(255, 0, 0), the green vertex Vg(0, 255, 0), the blue vertex Vb(0, 0, 255), the cyan vertex Vc(0, 255, 255), the magenta vertex Vm(255, 0, 255), the yellow vertex Vy(255, 255, 0), and the white vertex Vw(255, 255, 255). In this color gamut, a color is represented by color values of (red R, green G, blue B). The black vertex Vk(0, 0, 0) represents black, and the white vertex Vw(255, 255, 255) represents white.

[0101] Each of a plurality of pixels in the image data is represented by a color value in the color gamut of the RGB color space. In this color gamut, the closer the color value of a pixel is to the black vertex Vk, the darker the color of the pixel becomes, and when the color value of the pixel is equal to the black vertex Vk, the color of the pixel indicates the darkest black. Also, in the color gamut of the RGB color space, the closer the color value of a pixel is to the white vertex Vw, the brighter the color of the pixel becomes, and when the color value of the pixel is equal to the white vertex Vw, the color of the pixel indicates the brightest white.

[0102] In such a color gamut of the RGB color space, when the color value of a pixel is closer to the black vertex Vk than a first predetermined color value, the first control unit 50a determines that pixel as a dark pixel. For example, in the color gamut of the RGB color space, when the shortest distance between the color value of a pixel and the black vertex Vk is less than the shortest distance between the first predetermined color value and the black vertex Vk, the color value of that pixel is closer to the black vertex Vk than the first predetermined color value, and that pixel is determined as a dark pixel. Also, in the color gamut of the RGB color space, when the shortest distance between the color value of a pixel and the white vertex Vw is less than the shortest distance between the second predetermined color value and the white vertex Vw, the color value of that pixel is closer to the white vertex Vw than the second predetermined color value, and that pixel is determined as a bright pixel. Note that the second predetermined color value may be the same as the first predetermined color value or may be different from the first predetermined color value.

[0103] In addition, in the color conversion look-up table used for color conversion processing of image data, RGB values, which are color values in the color gamut of the RGB color space, and CMYK values are associated with each other. For example, the CMYK value (0, 0, 0, 100) is associated with the RGB value (0, 0, 0) of the black vertex Vk, and the CMYK value (0, 0, 0, 0) is associated with the RGB value (255, 255, 255) of the white vertex Vw. Also, the closer the color of a pixel is to the black vertex Vk, the larger the K value of the CMYK value becomes.

[0104] <Control method of printing device> The printing device 10 according to Embodiment 3 is controlled by a first control unit 50a and a second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 12. In the flowchart of FIG. 12, in addition to the processes of steps S10 to S17 in FIG. 6, the processes of steps S25 and S26 are executed between step S13 and step S14.

[0105] That is, the first control unit 50a acquires the image data of the inverted image B and the printing mode of its printing process (steps S10, S11). When the printing mode is the first printing mode (step S12: NO), the first control unit 50a executes a printing process in the first printing mode by the printing execution unit 12 (step S16) and outputs a first transfer condition corresponding to the first printing mode (step S17). Since the transfer energy of this first transfer condition is small, it is possible to reduce the transfer cost.

[0106] When the printing mode is the second printing mode in step S12 (step S12: YES), the first control unit 50a executes a usage limit process (step S13). In addition, the first control unit 50a executes a pixel acquisition process (step S25). In this pixel acquisition process, the first control unit 50a acquires the color values of a plurality of pixels constituting the inverted image B, which is a printed image, based on the image data, and determines whether the color value is closer to black than a first predetermined color value. When the color value is closer to black than the first predetermined color value, the first control unit 50a determines that pixel as a dark pixel and stores identification information such as the position information of the pixel in the first storage unit 52a.

[0107] Then, the first control unit 50a executes a conversion process on the image data. Further, the first control unit 50a executes a color substitution process on the image data (step S26). In this color substitution process, the first control unit 50a acquires the color value of a dark pixel based on the image data and the pixel identification information stored in the first storage unit 52a, and replaces the black component of the dark pixel with single-color black by black ink from the mixed-color black by cyan ink, magenta ink, and yellow ink.

[0108] In this way, the first control unit 50a generates image data for the second printing mode and transmits it to the second control unit 50b. The second control unit 50b executes a printing process in the second printing mode based on this image data and prints the inverted image B on the printing medium A (step S14). Further, the first control unit 50a outputs the second transfer condition corresponding to the second printing mode as the transfer condition (step S15).

[0109] In this way, in the printing process of the second printing mode, black ink is used to form dark pixels in the inverted image B instead of a plurality of types of color inks. By using black ink to form dark pixels in this way, the amount of ink used can be reduced compared to the case of using a plurality of types of color inks. Further, the dark pixels in the transferred image C obtained by transferring the inverted image B are represented darker when black ink is used than when a plurality of types of color inks are used. Therefore, even if the amount of ink used for the inverted image B is small, a reduction in the image quality of the transferred image C can be suppressed.

[0110] <Modification Example 4> The printing apparatus 10 according to Modification Example 4 executes a color substitution process based on the number of dark pixels and the number of bright pixels in the partial image F in Embodiment 3. This printing apparatus 10 is controlled by a first control unit 50a and a second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 13. In the flowchart of FIG. 13, in addition to the processes of steps S10 to S13, S15 to S17 in FIG. 6, the processes of steps S25 to S30 are executed between step S13 and step S15.

[0111] That is, the first control unit 50a acquires the image data of the inverted image B and the printing mode (steps S10, S11). When the printing mode is the first printing mode (step S12: NO), the printing execution unit 12 executes printing processing in the first printing mode (step S16) and outputs the first transfer condition corresponding to the first printing mode (step S17). Since the transfer energy of this first transfer condition is small, it is possible to reduce the transfer cost.

[0112] When the printing mode is the second printing mode in step S12 (step S12: YES), the first control unit 50a executes usage reduction processing on the image data (step S13). Then, the first control unit 50a acquires partial image data of a part of the image data (step S27) and determines whether a flag is set for the partial image data (step S28).

[0113] Processing related to this flag is executed by the first control unit 50a according to the flowchart of FIG. 14. That is, as shown in FIG. 15, the first control unit 50a executes a division process of dividing the partial image F into a plurality of blocks F1 based on the partial image data (step S40). Then, the first control unit 50a acquires one unprocessed block F1 from the plurality of blocks F1 (step S41), acquires the color value for each of the plurality of pixels belonging to this block F1, and determines whether the color value is closer to black than the first predetermined color value. Then, the first control unit 50a executes a dark pixel number acquisition process of acquiring the number of dark pixels whose color value is closer to black than the first predetermined color value among the pixels belonging to the block F1 (step S42).

[0114] In addition, the first control unit 50a determines whether the color value for each of the plurality of pixels belonging to this block F1 is closer to white than the second predetermined color value. Then, the first control unit 50a executes a bright pixel number acquisition process of acquiring the number of bright pixels whose color value is closer to white than the second predetermined color value among the pixels belonging to the block F1 (step S43).

[0115] Then, the first control unit 50a executes a first pixel determination process for determining whether the number of dark pixels belonging to block F1 is greater than the number of bright pixels belonging to block F1 (step S44). Here, when the number of dark pixels is greater than the number of bright pixels (step S44: YES), the first control unit 50a determines this block F1 as a dark block, increments the count of the number of dark blocks by 1, and stores it in the first storage unit 52a (step S45). Thereby, a storage process for storing the number of dark blocks, which is the number of blocks F1 in which the number of dark pixels belonging to block F1 is greater than the number of bright pixels belonging to block F1, is executed.

[0116] On the other hand, when the number of dark pixels is less than or equal to the number of bright pixels (step S44: NO), the first control unit 50a executes a second pixel determination process for determining whether the number of bright pixels belonging to block F1 is greater than the number of dark pixels belonging to block F1 (step S46). Here, when the number of bright pixels is the same as the number of dark pixels (step S46: NO), the first control unit 50a proceeds to the process of step S48.

[0117] When the number of bright pixels is greater than the number of dark pixels in step S46 (step S46: YES), the first control unit 50a determines this block F1 as a bright block, increments the count of the number of bright blocks by 1, and stores it in the first storage unit 52a (step S47). Thereby, a storage process for storing the number of bright blocks, which is the number of blocks F1 in which the number of bright pixels belonging to block F1 is greater than the number of dark pixels belonging to block F1, is executed.

[0118] Then, the first control unit 50a determines whether processing has been performed for all blocks F1 included in the partial image F (step S48). If there are unprocessed blocks F1 remaining (step S48: NO), the first control unit 50a returns to the process of step S41 and executes the subsequent processes. On the other hand, when processing has been performed for all blocks F1 included in the partial image F (step S48: YES), the first control unit 50a executes a block number determination process for determining whether the number of dark blocks stored by the storage process is greater than the number of bright blocks (step S49).

[0119] Here, when the number of dark blocks is larger than the number of bright blocks (step S49: YES), the first control unit 50a executes a flag process to set a flag for this partial image F (step S50). The flag of this partial image F is stored in the first storage unit 52a. On the other hand, when the number of dark blocks is less than or equal to the number of bright blocks (step S49: NO), no flag can be set for this partial image F.

[0120] The first control unit 50a returns to the process of step S28 in FIG. 13 and determines whether a flag is set for the partial image F of the partial image data. Here, when a flag is set for the partial image F (step S28: YES), the first control unit 50a executes a pixel acquisition process on the partial image data and stores the identification information of the dark pixels in the partial image F in the first storage unit 52a (step S25). Then, the first control unit 50a executes a conversion process on the image data and also executes a color substitution process on the image data (step S26). Thereby, the black component of the dark pixels is replaced from the mixed-color black by a plurality of types of color inks to the single-color black by the black ink.

[0121] When no flag is set for the partial image F in step S28 (step S28: NO), the first control unit 50a does not execute the pixel acquisition process in step S25 and the color substitution process in step S26. Thereby, the black component of the dark pixels cannot be replaced from the mixed-color black by a plurality of types of color inks to the single-color black by the black ink.

[0122] In this way, the first control unit 50a generates partial image data of the print format for the second print mode and transmits it to the second control unit 50b. The second control unit 50b executes print processing in the second print mode based on this partial image data, and prints a partial image F of the inverted image B on the print medium A (step S29). Then, the first control unit 50a determines whether all the partial images F constituting the print image have been printed (step S30). Here, if there remains a partial image F that has not been printed (step S30: NO), the first control unit 50a returns to the process of step S27 and executes the subsequent processes. On the other hand, if all the partial images F have been printed (step S30: YES), the inverted image B of the print image composed of all the partial images F is printed on the print medium A. Then, the first control unit 50a outputs the second transfer condition corresponding to the second print mode as the transfer condition (step S15).

[0123] <Embodiment 4> The printing apparatus 10 according to Embodiment 4 determines transfer conditions based on the number of dark pixels and the number of bright pixels in the print image in Embodiments 1 - 3 and Modification Examples 1 - 4. In this case, the printing apparatus 10 is controlled by the first control unit 50a and the second control unit 50b as the control unit 50 according to the flowchart shown in the example of FIG. 16. In the flowchart of FIG. 16, in addition to the processes of steps S10 - S17 in FIG. 6, the process of step S31 is executed between step S14 and step S15.

[0124] That is, the first control unit 50a acquires the image data of the inverted image B which is the print image and the print mode (steps S10, S11). When the print mode is the second print mode (step S12: YES), the first control unit 50a executes usage reduction processing on the image data (step S13), and the second control unit 50b executes print processing in the second print mode and prints the inverted image B on the print medium A (step S14). Then, the first control unit 50a determines whether a flag is set for this inverted image B (step S31).

[0125] The processing related to this flag is executed by the first control unit 50a in accordance with the flowchart of FIG. 17. That is, the first control unit 50a divides the print image into a plurality of blocks based on the image data (step S60), and acquires one unprocessed block from the plurality of blocks (step S61). A block is a partial area of the print image. Then, the first control unit 50a acquires the color value for each of the plurality of pixels belonging to this block, and determines whether the color value is closer to black than a first predetermined color value. And when the color value is closer to black than the first predetermined color value, the first control unit 50a regards the pixel with that color value as a dark pixel, and acquires the number of dark pixels in the block (step S62).

[0126] Also, the first control unit 50a determines for each of the plurality of pixels belonging to this block whether the color value is closer to white than a second predetermined color value. And when the color value is closer to white than the second predetermined color value, the first control unit 50a regards the pixel with that color value as a bright pixel, and acquires the number of bright pixels in the block (step S63). In this way, a pixel number acquisition process is executed to acquire the number of dark pixels whose color value is closer to black than the first predetermined color value and the number of bright pixels whose color value is closer to white than the second predetermined color value among the pixels of the print image based on the image data.

[0127] Then, the first control unit 50a determines whether the number of dark pixels belonging to the block is greater than the number of bright pixels belonging to the block (step S64). Here, when the number of dark pixels is greater than the number of bright pixels (step S64: YES), the first control unit 50a designates this block as a dark block, increments the count of the number of dark blocks by 1, and stores it in the first storage unit 52a (step S65). Thereby, an area number acquisition process is executed to acquire the number of dark blocks (dark areas) in which the number of dark pixels is greater than the number of bright pixels in the print image.

[0128] On the other hand, when the number of dark pixels is less than or equal to the number of bright pixels (step S64: NO), the first control unit 50a determines whether the number of bright pixels belonging to the block is greater than the number of dark pixels belonging to the block (step S66). Here, when the number of bright pixels is equal to the number of dark pixels (step S66: NO), the first control unit 50a proceeds to the process of step S68.

[0129] When the number of bright pixels is greater than the number of dark pixels in step S66 (step S66: YES), the first control unit 50a sets this block as a bright block, increments the count of the number of bright blocks by 1, and stores it in the first storage unit 52a (step S67). Thereby, the area number acquisition process for acquiring the number of bright blocks (bright regions) in which the number of bright pixels is greater than the number of dark pixels in the printed image is executed.

[0130] Then, the first control unit 50a determines whether processing has been performed for all blocks included in the printed image (step S68). If there are unprocessed blocks remaining (step S68: NO), the first control unit 50a returns to the process of step S61 and executes the subsequent processes. On the other hand, when processing has been performed for all blocks included in the printed image (step S68: YES), the first control unit 50a determines whether the number of dark blocks stored in the first storage unit 52a is greater than the number of bright blocks (step S69). Thereby, the area determination process for determining whether the number of dark blocks (number of dark regions) is greater than the number of bright blocks (number of bright regions) is executed.

[0131] Here, when the number of dark blocks is greater than the number of bright blocks (step S69: YES), the first control unit 50a sets a flag for this printed image (step S70). The flag of this printed image is stored in the first storage unit 52a. On the other hand, when the number of dark blocks is less than or equal to the number of bright blocks (step S69: NO), this printed image cannot be flagged.

[0132] The first control unit 50a returns to the process of step S31 in FIG. 16 and determines whether a flag is set for the printed image. Here, if a flag is set for the printed image (step S31: YES), the color tone of the printed image is dark. Therefore, the first control unit 50a outputs the second transfer condition corresponding to the second printing mode as the transfer condition (step S15). As a result, even when the color tone of the inverted image B, which is the printed image, is dark and the density reduction due to the decrease in the ink amount is likely to be noticeable, the inverted image B is transferred under the second transfer condition in which the transfer energy is greater than the first transfer condition. For this reason, the decrease in the ink amount due to transfer can be suppressed, and the deterioration of the image quality of the transferred image C transferred to the transfer medium E can be suppressed.

[0133] On the other hand, if a flag is not set for the printed image (step S31: NO), the color tone of the printed image is bright. Therefore, the first control unit 50a outputs the first transfer condition corresponding to the first printing mode as the transfer condition (step S17). As a result, when the color tone of the inverted image B, which is the printed image, is bright and the density reduction due to the decrease in the ink amount is hardly noticeable, the inverted image B is transferred under the first transfer condition in which the transfer energy is smaller than the second transfer condition. For this reason, the reduction of the transfer cost can be achieved.

[0134] <Other Modifications> In all of the above embodiments and modifications, the printing apparatus 10 is configured by the separately provided information processing unit 11 and printing execution unit 12, but the printing apparatus 10 may be configured by the integrally provided information processing unit 11 and printing execution unit 12. In this case, the control unit 50 of the printing apparatus 10 may be configured by one device, or may be configured by a plurality of devices that operate in cooperation.

[0135] The above-described embodiments may be combined with each other as long as they do not exclude each other. Also, from the above description, many improvements and other embodiments of the present disclosure will be apparent to those skilled in the art. Accordingly, the above description should be construed as illustrative only and provided for the purpose of teaching those skilled in the art the best mode of carrying out the present disclosure. Without departing from the spirit of the present disclosure, the details of its structure and / or function can be substantially changed.

Description of Reference Numerals

[0136] 10: Printing apparatus 20: Head 21: Nozzle 21a: First nozzle 21b: Second nozzle 30: Moving device 50: Control unit

Claims

1. a head that discharges sublimable ink; a control unit, and includes: the control unit: Performs printing processing to discharge ink from the head onto a medium to be printed according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode, based on image data; When the printing mode is the second printing mode, as transfer conditions for transferring the printed image printed on the medium to be printed to a transfer medium by the printing processing, among a first transfer condition and a second transfer condition in which the transfer energy for transferring the printed image from the medium to be printed to the transfer medium is greater than the first transfer condition, executes a first output process for outputting the second transfer condition; A printing apparatus.

2. the control unit: Executes a characteristic determination process for determining whether or not the transfer medium has heat resistance, and When it is determined in the characteristic determination process that the transfer medium does not have heat resistance, outputs the first transfer condition as the transfer condition in the first output process. The printing apparatus according to claim 1.

3. The printing mode of the printing processing is a mode different from the first printing mode and the second printing mode and has a third printing mode for forming the printed image of a thin line, The transfer condition has a third transfer condition in which the transfer energy is smaller than the first transfer condition, the control unit: Executes a second determination process for determining whether or not the printing mode is the third printing mode, and When it is determined in the second determination process that the printing mode is the third printing mode, executes a second output process for outputting the third transfer condition as the transfer condition. The printing apparatus according to claim 1.

4. Further includes a moving device that moves the head along a moving direction, the control unit: Executes a first determination process for determining whether or not the printing mode is the second printing mode, and When it is determined in the first determination process that the printing mode is the second printing mode, executes the bidirectional printing process of discharging ink from the head in the forward and return paths in the moving direction, and When it is determined in the first determination process that the printing mode is not the second printing mode, executes the unidirectional printing process of discharging ink from the head in the forward or return path in the moving direction. The printing apparatus according to claim 1.

5. Further includes a moving device that moves the head along a moving direction, the control unit: Execute a first determination process for determining whether or not the printing mode is the second printing mode. When the printing mode is the second printing mode in the first determination process, execute the bidirectional printing process of discharging ink from the head in the forward and return paths of the moving direction. When the printing mode is not the second printing mode in the first determination process, based on the color difference between the image obtained by discharging ink from the head in the forward path of the moving direction and the image obtained by discharging ink from the head in the return path of the moving direction, execute a direction determination process for determining whether to discharge ink from the head in the forward or return path of the moving direction. The printing apparatus according to claim 1.

6. The head has a first nozzle that discharges a plurality of types of color inks including two or more types of color inks capable of expressing black by color mixing, and a second nozzle that discharges black ink. The control unit A first determination process for determining whether or not the printing mode is the second printing mode, A pixel acquisition process for acquiring dark pixels among the pixels of the printed image based on the image data, where the color value is closer to black than a first predetermined color value, When the printing mode is the second printing mode in the first determination process, execute a color substitution process of using the black ink instead of color mixing the plurality of types of color inks for forming the dark pixels in the printing process. The printing apparatus according to claim 1.

7. Further include a moving device that moves the head along the moving direction, The control unit In the printing process, while moving the head along the moving direction based on a part of the partial image data of the image data, discharge ink from the head to form a partial image of a part of the printed image. A first determination process for determining whether or not the printing mode is the second printing mode, A division process for dividing the partial image into a plurality of blocks based on the partial image data, A dark pixel number acquisition process for acquiring the number of dark pixels among the pixels belonging to the block, where the color value is closer to black than a first predetermined color value, A bright pixel number acquisition process for acquiring the number of bright pixels among the pixels belonging to the block, where the color value is closer to white than a second predetermined color value, A first pixel determination process for determining whether or not the number of the dark pixels belonging to the block is greater than the number of the bright pixels belonging to the block. A second pixel determination process for determining whether the number of bright pixels belonging to the block is greater than the number of dark pixels belonging to the block; A storage process for storing the number of dark blocks, which is the number of blocks in which the number of dark pixels belonging to the block is greater than the number of bright pixels belonging to the block, and the number of bright blocks, which is the number of blocks in which the number of bright pixels belonging to the block is greater than the number of dark pixels belonging to the block; A block number determination process for determining whether the number of dark blocks stored by the storage process is greater than the number of bright blocks; A flag process for setting a flag when the number of dark blocks is greater than the number of bright blocks; Execute, When the flag is set by the flag process and the printing mode is the second printing mode in the first determination process, execute the color substitution process. The printing apparatus according to claim 6.

8. The head includes a first nozzle including nozzles that eject a plurality of types of color inks including two or more types of color inks that can express black by mixing colors, and a second nozzle that ejects black ink. The control unit, A first determination process for determining whether the printing mode is the second printing mode; A pixel number acquisition process for acquiring the number of dark pixels among the pixels of the printed image based on the image data, the color value of which is closer to black than a first predetermined color value, and the number of bright pixels, the color value of which is closer to white than a second predetermined color value; An area number acquisition process for acquiring the number of dark areas in the printed image where the number of dark pixels is greater than the number of bright pixels, and the number of bright areas where the number of bright pixels is greater than the number of dark pixels; An area determination process for determining whether the number of dark areas is greater than the number of bright areas; When the number of dark areas is greater than the number of bright areas and the printing mode is the second printing mode in the first determination process, output the second transfer condition as the transfer condition in the first output process; When the number of dark areas is less than or equal to the number of bright areas and the printing mode is the second printing mode in the first determination process, output the first transfer condition as the transfer condition in the first output process. The printing apparatus according to claim 1.

9. A control method for a printing apparatus including a head that ejects ink having sublimability. Based on the image data, a printing process of ejecting ink from the head onto the medium to be printed is performed according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode. When the printing mode is the second printing mode, as transfer conditions for transferring the printed image printed on the medium to be printed to the transfer medium by the printing process, among a first transfer condition and a second transfer condition in which the transfer energy for transferring the printed image from the medium to be printed to the transfer medium is greater than the first transfer condition, a first output process of outputting the second transfer condition is executed. A control method for a printing apparatus.

10. In a printing apparatus including a head that ejects sublimable ink, Based on the image data, a printing process of ejecting ink from the head onto the medium to be printed is performed according to one mode selected from at least printing modes including a first printing mode and a second printing mode in which the amount of ink used is less than that in the first printing mode. When the printing mode is the second printing mode, as transfer conditions for transferring the printed image printed on the medium to be printed to the transfer medium by the printing process, among a first transfer condition and a second transfer condition in which the transfer energy for transferring the printed image from the medium to be printed to the transfer medium is greater than the first transfer condition, a first output process of outputting the second transfer condition is executed. A program.

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