Inkjet printing apparatus, inkjet printing method, and inkjet printing system

Abstract

The invention discloses an ink-jet printing apparatus, an ink-jet printing method, and an ink-jet printing system. An inkjet printing apparatus includes: a printhead that prints an image by ejecting a coloring ink containing a coloring agent and a coloring agent coagulation reaction liquid onto a printing medium; a printer unit that causes the printhead to print a test pattern on a print medium by printing a first pattern image with a predetermined volume of colored ink and printing a second pattern image with a different volume of reaction liquid; a dryer unit that dries the test pattern on the print medium during printing of the test pattern on the print medium under the control of the printer unit; an obtaining unit that obtains print information relating to a print result of the test pattern; and a determination unit that determines a volume of the reaction liquid for printing on the printing medium and a drying condition of the dryer unit based on the printing information obtained by the obtaining unit.

Description

Technical Field

[0001] The present disclosure relates to an inkjet printing apparatus, an inkjet printing method, and an inkjet printing system, and to a technology for preventing ink from seeping out on a printing medium by using a reaction liquid. Background Art

[0002] This type of inkjet printing device ejects ink and a reaction liquid onto a print medium together and brings the reaction liquid into contact with the ink on the print medium, thereby condensing the colorant in the ink. This condensation of the colorant prevents the ink from seeping out on the print medium, and it is expected to improve the print quality. Regarding this technology, Japanese Patent Publication No. 2018-149735 (Document 1) describes printing on a print medium with low ink permeability (absorbency) using a reaction liquid. With this, even on a print medium with low ink absorbency that allows ink to easily seep out, it is possible to achieve high-quality printing by preventing the ink from seeping out.

[0003] Furthermore, particularly for printing on a printing medium having low ink absorbency, a conventional technique of drying the printed area to fix the printed image has been used.

[0004] However, in some cases, it is not possible to fully achieve the prevention of bleeding and the improvement of fixing only by controlling the application of the reaction liquid and controlling the drying conditions as disclosed in Document 1. Specifically, the appropriate reaction liquid volume and the appropriate drying conditions vary depending on the wettability of the print medium used. For example, even a print medium with low absorbency is classified as an easy-to-wet print medium or a difficult-to-wet print medium according to the surface energy state of the print medium. Such a surface energy state of the print medium varies depending on, for example, the processing conditions of the print medium. Therefore, even if the print medium has a similar absorbency level, the print medium has different wettability levels, which results in different combinations of the appropriate reaction liquid volume and the appropriate drying conditions. Summary of the invention

[0005] An inkjet printing device disclosed herein includes: a print head configured to print an image by ejecting a coloring ink and a reaction liquid onto a printing medium, the coloring ink containing a colorant, the reaction liquid contacting the colorant and causing the colorant to condense; a printer unit configured to cause the print head to print a plurality of test patterns on the printing medium by correspondingly printing a first pattern image with a predetermined volume of the coloring ink and correspondingly printing a second pattern image with respective different volumes of the reaction liquid, the plurality of test patterns consisting of a plurality of first image patterns and a plurality of accompanying second pattern images; a dryer unit configured to dry the plurality of test patterns on the printing medium during the printing of the plurality of test patterns on the printing medium under the control of the printer unit; an obtaining unit configured to obtain printing information corresponding to the printing results of each of the plurality of test patterns; and a determining unit configured to determine the volume of the reaction liquid used for printing on the printing medium and the drying conditions of the dryer unit based on the printing information obtained by the obtaining unit.

[0006] Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a perspective view schematically illustrating an inkjet printing apparatus according to a first embodiment of the present disclosure;

[0008] Figure 2 is a schematic diagram illustrating a schematic structure of an inkjet printing device according to a first embodiment of the present disclosure;

[0009] Figure 3 is a view schematically illustrating an ejection orifice array on a print head according to a first embodiment of the present disclosure;

[0010] Figure 4 is a block diagram illustrating a control configuration of an inkjet printing apparatus according to a first embodiment of the present disclosure;

[0011] Figure 5 is a view schematically illustrating multi-pass printing control according to the first embodiment of the present disclosure;

[0012] FIG. 6A to FIG. 6D is a schematic diagram for explaining a mask pattern according to a first embodiment of the present disclosure;

[0013] Figure 7 is a schematic diagram illustrating a UI for print medium selection according to a first embodiment of the present disclosure;

[0014] FIG. 8A to FIG. 8Cis a diagram for explaining quantification of “wettability” of a printing medium according to the first embodiment of the present disclosure; Fig. 8A illustrates an example of parameters for determining a contact angle θ, which is the angle between a tangent line to a liquid droplet and a solid surface; Figure 8B is a diagram illustrating a printing medium P having an easy-wetting property; Figure 8C is a diagram illustrating a printing medium P having a difficult-to-wet property;

[0015] Fig. 9 is a diagram for explaining the classification of printing media according to the "absorbency" and "wettability" of the printing media;

[0016] Fig.10 is a diagram for explaining drying conditions according to the first embodiment of the present disclosure;

[0017] Fig.11 is a diagram for explaining a test pattern according to a first embodiment of the present disclosure;

[0018] Fig.12 is a view presenting a printing result of a test pattern on a printing medium having a hard-wetting property under a first drying condition according to the first embodiment of the present disclosure;

[0019] Fig.13 is a view presenting a printing result of a test pattern on a printing medium having an easy-wetting property under a first drying condition according to a first embodiment of the present disclosure;

[0020] Fig.14 is a view presenting a printing result of a test pattern on a printing medium having an easy-wetting property under air blowing according to the first embodiment of the present disclosure;

[0021] Fig.15 is a flowchart presenting a process of determining drying conditions and a reaction liquid volume for printing according to a first embodiment of the present disclosure;

[0022] Fig.16 is a flowchart presenting a first variation of the process of determining the drying conditions and the volume of the reaction liquid for printing according to the first embodiment of the present disclosure;

[0023] Fig.17 is a flowchart presenting a second variation of the process of determining the drying conditions and the volume of the reaction liquid for printing according to the first embodiment of the present disclosure;

[0024] Fig.18 is a flowchart presenting a process of determining drying conditions and a reaction liquid volume for printing according to a second embodiment of the present disclosure;

[0025] Fig.19is a diagram for explaining a test pattern according to a third embodiment of the present disclosure;

[0026] Fig. 20 is a view presenting a printing result of a test pattern on a printing medium having a difficult-wetting property under a first drying condition according to a third embodiment of the present disclosure;

[0027] Fig.21 is a view presenting a printing result of a test pattern on a printing medium having an easy-wetting property under a first drying condition according to a third embodiment of the present disclosure;

[0028] Fig. 22 is a view presenting a printing result of a test pattern on a printing medium having an easy-wetting property under a second drying condition according to a third embodiment of the present disclosure; and

[0029] Fig.23 2 is a diagram for explaining other test patterns according to the third embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The following embodiments are not intended to limit the matters disclosed herein. In addition, all combinations of the features described in the following embodiments are not necessary for the solutions of the present disclosure. Here, the same constituent elements will be represented by the same reference symbols.

[0031] <<First Embodiment>>

[0032] A description will be given of a first embodiment of the present disclosure capable of obtaining a high-quality image by controlling a dryer unit according to wettability.

[0033] <Printing Device Structure>

[0034] Figure 1 : is a perspective view schematically illustrating an outer appearance structure of an inkjet printing apparatus (hereinafter also simply referred to as a “printing apparatus”) according to a first embodiment of the present disclosure. Figure 2 is a diagram illustrating a first embodiment according to the present disclosure Figure 1 Schematic diagram of the schematic structure of the inkjet printing device.

[0035] Figure 3 is a diagram illustrating a first embodiment according to the present disclosure Figure 1 and Figure 2 Schematic diagram of the ejection orifice array on the print head 105 in FIG. Figure 4 1 is a block diagram illustrating a control configuration of an inkjet printing apparatus according to a first embodiment of the present disclosure. Figure 1 and Figure 2, the XYZ coordinate axes are shown as corresponding arrows. The Y axis indicates the conveying direction of the print medium P being conveyed. The print medium P is conveyed in the direction indicated by the Y axis arrow. The X axis indicates the scanning direction of the carriage unit 102 (print head 105). Scanning is performed in the direction indicated by the X axis arrow. In the case of reciprocating printing, scanning is performed in the direction indicated by the X axis arrow and in the direction opposite to the direction indicated by the X axis arrow. The Z axis indicates the height direction of the printing device.

[0036] Figure 1 The inkjet printing device in is a so-called serial scanning type printing device. This inkjet printing device prints an image by scanning the print head 105 in the X direction (main scanning direction) orthogonal to the Y direction (transport direction). Figures 1 to 4 , the structure of the inkjet printing device and its printing operation will be briefly described below. First, Figure 2 The transmission unit 201 in Figure 4 The sub-scanning motor 421 in FIG. 4 is driven via a gear (not shown). Figure 1 The reel 101 in the printing medium P is composed of Figure 1 The transport unit 201 in the embodiment of the present invention transports the printing medium P in the Y direction while maintaining the printing medium P. Figure 1 and Figure 2 The guide shaft 103 in the embodiment extends in the X direction to allow Figure 1 and Figure 2 The carriage unit 102 in the embodiment is moved at a predetermined transfer position. Figure 4 The main scanning motor 420 scans. Figure 1 and Figure 2 The carriage unit 102 in the image is scanned along the guide shaft 103, thereby performing reciprocating scanning (reciprocating movement) along the outward path in the +X direction and the return path in the -X direction. During this scanning process, Figure 4 The controller 400 in is synchronized with the timing based on the position signal obtained by the encoder 106 provided along the main scanning direction. Then, Figure 4 The controller 400 in the embodiment causes the print head 105 attachable to the carriage unit 102 to perform an ejection operation from its ejection orifice, thereby printing on the print medium P. During the reciprocating scanning, as in the case of the print head 105, Figure 4The controller 400 in the processing is synchronous with the timing based on the position signal obtained by the encoder 106 and the detection signal corresponding to the position of the carriage unit 102. The carriage belt (not shown) can be used to transmit the driving force from the main scanning motor 420 to the carriage unit 102. Instead of the carriage belt, the printing device may include, for example, a lead screw (not shown) extending in the X direction and configured to be rotated by the main scanning motor 420, and an engaging portion provided to the carriage unit 102 and engaged with the groove of the lead screw. In this way, the printing device can use any other type of driving method. The fed printing medium P is held and conveyed between the sheet feeding roller 201A and the clamping roller 201B of the conveying unit 201, and is guided to the printing position (scanning area of ​​the print head 105) on the platen 104. In general, the face surface of the print head 105 is covered by a cover in a non-operating state. Therefore, the user opens the cover before printing. Therefore, the user prepares the print head 105 and the carriage unit 102 for scanning. Thereafter, once data for one scan is accumulated in a buffer (not shown), the data is read by using Figure 4 The main scanning motor 420 scans Figure 1 and Figure 2 The carriage unit 102 in performs printing as described above. Here, Figure 1 The reflective optical sensor 107 in FIG. 1 includes, for example, a light emitting portion constituted by an LED and a light receiving portion constituted by a photodiode. The reflective optical sensor 107 can detect the density of a test pattern printed on the print medium P as an optical reflectance.

[0037] Figure 2 The conveying unit 201 in the embodiment includes a sheet feeding roller 201A and a pinch roller 201B. Figure 1 The reel 101 in the sheet conveys the print medium P while the print medium P is held and conveyed between the sheet feeding roller 201A and the pinch roller 201B. Figure 1 The print medium P transported by the reel 101 in the printing unit is printed by the print head 105 and then wound around a winding shaft (not shown). Thus, a rolled medium is formed. The print head 105 attached to the carriage unit 102 ejects ink. The print head 105 applies ink to the print medium P while scanning in the X direction using the carriage unit 102. In this process, the print medium P is intermittently transported in the +Y direction by the transport unit 201, so that an image is formed on the surface of the print medium P. The platen 104 is arranged to face the scanning area of ​​the print head 105 and the carriage unit 102. The platen 104 sucks the print medium P from the back side of the print medium P to prevent the print medium P from floating up. Figure 2 In the example of FIG. 1 , it is assumed that the print medium P is fed from a roll state and then wound into a roll state again after printing. Figure 2In the example of FIG. 1 , it is assumed that the use form of the print medium P is a roll-to-roll form. The use form of the print medium P is not limited to the roll-to-roll form. The use form of the print medium P may be, for example, a single-sheet form.

[0038] Next, a structure for fixing ink on the print medium P by drying the ink will be described. The printing device includes a platen blower unit 202. The platen blower unit 202 is arranged upstream of the carriage unit 102. The platen blower unit 202 is a unit configured to blow heated air to the surface of the print medium P on the platen 104. This makes it possible to promote the evaporation of water contained in the ink on the surface of the print medium P ejected on the platen 104, and promote the fixing of the ink. Specifically, the platen blower unit 202 includes a fan 202A and a heater 202B. The fan 202A includes, for example, an axial flow fan used as a blower. The heater 202B includes, for example, an electric heater attached to the blowing side of the fan 202A and used as a temperature adjuster. Therefore, when the heater 202B is turned on, the air blown out from the fan 202A is heated. The heated air is blown out from the fan 202A and passes between the print head 105 and the print medium P on the platen 104. This makes it possible to promote evaporation of moisture contained in the ink ejected from the print head 105 on the surface of the printing medium P on the platen 104 and promote fixing of the ink.

[0039] The printing device includes a fixing unit 203. The fixing unit 203 is arranged downstream of the carriage unit 102. The fixing unit 203 is a unit configured to dry and fix the ink applied on the print medium P. The fixing unit 203 has a substantially box shape and has a bottom surface of a conveying surface facing the conveying route of the print medium P. By blowing hot air from the bottom surface to the print medium P, the fixing unit 203 heats the ink and the print medium P, evaporates the water and solvent contained in the ink, and thus turns the emulsion into a film. Specifically, the fixing unit 203 includes a fan 203A, a heater 203B and a fixing housing 203C. The shape of the fixing housing 203C is substantially a box shape. An opening is formed at the bottom surface portion of the fixing housing 203C. The fan 203A includes, for example, an axial flow fan used as a blower. The heater 203B includes, for example, an electric heater used as a temperature regulator. Therefore, when the heater 203B is turned on, the air blown out from the fan 203A is heated. The heated air is blown out from the fan 203A and passes along the surface of the print medium P. This makes it possible to dry and fix the ink by more quickly evaporating water and solvent contained in the ink ejected from the print head 105 onto the surface of the print medium P and turning the emulsion into a film.

[0040] The printing device includes a downflow unit 204. The downflow unit 204 is arranged at a position covering the fixing unit 203 from the outside. The downflow unit 204 blows the hot air exhausted from the fixing unit 203 toward the bottom direction. Specifically, the downflow unit 204 includes a downflow fan 204A and a downflow housing 204C. Figure 2 In the example of , the downflow housing 204C is formed into a shape covering the fixing housing 203C. The downflow housing 204C is provided with openings formed on its upstream side and its downstream side, respectively. The downstream opening of the downflow housing 204C faces the vertical direction. Specifically, the downstream opening of the downflow housing 204C faces the -Z direction. The downflow fan 204A includes an axial flow fan used as a blower, for example. With this, the air sucked from the upstream of the downflow housing 204C is discharged from the downstream opening of the downflow housing 204C. This makes it possible to guide the air discharged from the fixing unit 203 in the bottom direction and blow the guided air toward the bottom.

[0041] The printing device includes an air curtain unit 205. The air curtain unit 205 can be provided between the platen 104 and the fixing unit 203. The air curtain unit 205 can prevent the ink mist blown out by the platen blower unit 202 from entering the interior of the fixing unit 203. Specifically, the air curtain unit 205 includes an air curtain fan 205A. The air curtain fan 205A includes, for example, an axial flow fan. The air curtain fan 205A is arranged so that the central axis of the air curtain fan 205A faces the upstream end 203CL of the bottom surface portion of the fixing housing 203C. Therefore, the air blown out from the air curtain fan 205A passes between the bottom surface portion of the fixing housing 203C and the surface of the printing medium P. This can prevent the ink mist from entering the fixing unit 203.

[0042] (Ink containing colorant)

[0043] refer to Figure 3 , the ejection orifice array in the print head 105 will be described. The print head 105 includes ejection orifice arrays 31, 32, 33 and 34. The ejection orifice array 31 ejects black ink as the ink containing the colorant. The ejection orifice array 32 ejects cyan ink as the ink containing the colorant. The ejection orifice array 33 ejects magenta ink as the ink containing the colorant. The ejection orifice array 34 ejects yellow ink as the ink containing the colorant. Each of the black ink, cyan ink, magenta ink and yellow ink is an ink containing a colorant. In the following description, each of the inks containing the colorant is also referred to as a colored ink.

[0044] (Reaction solution without colorant)

[0045] The print head 105 also includes an ejection orifice array 35. The ejection orifice array 35 ejects a colorant-free reaction liquid. In the present embodiment, the head structure for ejecting the orifice array 35 is separated from the head structure for coloring ink. The reaction liquid (also referred to as reaction liquid ink) does not contain a colorant. The reaction liquid ink contains a reaction component. The reaction component reacts with the colorant contained in the coloring ink. Specifically, when the coloring ink is brought into contact with the reaction liquid ink on the print medium P, the reaction liquid ink can cause the colorant contained in the coloring ink to condense. In this way, the reaction liquid ink can prevent seepage. In this specification, the term "ink" in some cases includes not only coloring ink but also reaction liquid ink.

[0046] The jet orifice arrays 31 to 35 are sequentially arranged in the jet orifice surface 105S of the print head 105 from the left to the right in the X direction. In each of the jet orifice arrays 31 to 35, 1280 jet orifices 36 are arranged in the Y direction (also referred to as the array direction) at a density of 1200dpi. The jet orifices 36 of the jet orifice arrays 31 to 34 eject coloring ink. The jet orifice 36 of the jet orifice array 35 ejects reaction liquid ink. In the present embodiment, the volume of the ink droplet ejected from each jet orifice 36 at one time is about 5pl. Each of the jet orifice arrays 31, 32, 33, 34 and 35 is connected to an ink tank (not shown) storing the corresponding ink. Therefore, the jet orifice arrays 31, 32, 33, 34 and 35 are supplied with corresponding ink from the corresponding ink tank (not shown). The print head 105 and each ink tank used in the present embodiment can be constructed to be separable from each other, but the structure is not limited thereto. For example, the print head 105 and the ink tank used in the present embodiment may be constructed integrally. Detailed components of the black ink, cyan ink, magenta ink, yellow ink, and reaction liquid will be described later.

[0047] (Controller 400)

[0048] like Figure 4 As shown in , the control configuration of the printing device includes a controller 400, an interface (I / F) 405, an operation section 406, a sensor group 411, a head driver 414, a main scanning motor driver 415, a sub-scanning motor driver 416, and a recovery processor 417. The control configuration of the printing device may include a host device 404. Alternatively, the control configuration of the printing device may include an image capturing section 441. In addition, the control configuration of the printing device may include a display section 442. The controller 400 serves as a main control section. In Figure 4In the example of , the controller 400 includes a central processing unit (CPU) 401, a read-only memory (ROM) 402, and a random access memory (RAM) 403. The controller 400 is, for example, in the form of a microcomputer, including the CPU 401, the ROM 402, the RAM 403, etc. In the case where the controller 400 is configured as a microcomputer, the controller 400 may include an I / O not shown. The ROM 402 stores therein programs, predetermined tables, or other fixed data for implementing various control modules for various controls of the printing device. In the RAM 403, an area for opening programs for implementing various control modules, an area for developing image data, a work area, etc. are appropriately allocated. The CPU 401 can also perform a process for adjusting the impact position, which will be described later. In the process for adjusting the impact position, the CPU 401 sets an adjustment value for adjusting the impact position. This adjustment value will be used to adjust the impact position in the actual printing process later and thereafter. The host device 404 is an image data supply source. The host device 404 can create data about an image for printing, etc. Alternatively, the host device 404 can perform processing on the image data for printing, etc. Alternatively, the host device 404 can be equipped with a reader unit for reading images. The host device 404 includes, for example, an input interface unit such as a display and a keyboard, and an electronic calculator capable of performing transmission and reception with the outside. The host device 404 can supply image data, other commands, status signals, etc. to the controller 400 via an interface (I / F) 405. Therefore, the controller 400 sends and receives image data, other commands, status signals, etc. via the interface (I / F) 405. The host device 404 can be implemented by another printing device. Alternatively, the host device 404 can be implemented by a terminal such as a smart phone.

[0049] (Operation unit 406)

[0050] The operation section 406 includes a power switch 407, a print start switch 408, a recovery switch 409, and an impact position adjustment start switch 410. The operation section 406 has a function of receiving an instruction input by an operator (also referred to as a user). In the operation section 406, the power switch 407, the print start switch 408, the recovery switch 409, and the impact position adjustment start switch 410 are used as a switch group. The power switch 407 is a switch for switching whether to supply power from a power source to the printing device. As the power source, a commercially available power source can be used, but the power source is not particularly limited thereto. For example, in the case where the printing device includes a secondary battery therein, the secondary battery can be used as the power source. The print start switch 408 is a switch for instructing the printing device to start printing on the print medium P. The recovery switch 409 is a switch for instructing the start of suction and recovery operations on the print head 105. The impact position adjustment start switch 410 is a switch for adjusting the impact position of ink. In the present embodiment, it is assumed that the print start, the recovery operation, and the impact position adjustment are performed in response to the operation of the switch provided to the printing device body. However, the printing start, recovery operation and impact position adjustment can be performed based on the instruction from the host device 404. The operation part 406 can also include an input part 431. The input part 431 has a function of receiving user input. For example, in the case where the information contained in the user's input received in the input part 431 indicates the printing information about the printing image status of multiple test patterns on the printing medium P, the CPU 401 can cause the RAM 403 to store the received user's input as printing information. Although not shown, a storage device for storing printing information can be provided outside the controller 400. This storage device can include, for example, a hard disk drive (HDD). Alternatively, the storage device can include, for example, a semiconductor memory such as a solid state drive (SSD).

[0051] (Sensor Group 411)

[0052] The sensor group 411 includes a photocoupler 412 and a temperature sensor 413. The sensor group 411 has a function of detecting the status of the printing device. The sensor group 411 may include, for example Figure 1 The reflective optical sensor 107 in the slide unit 102. The photocoupler 412 detects the initial position of the slide unit 102. The temperature sensor 413 detects the ambient temperature. The temperature sensor 413 is mounted on a suitable part. For example, the temperature sensor 413 can be mounted on Figure 2 In this installation structure, it is possible to detect the air flow from the platen blower unit 202. Figure 2 The temperature of the air blown out by the platen blower unit 202.

[0053] (Head driver 414)

[0054] Figure 2 The print head 105 includes Figure 4 The jet heater 419 and Figure 4 Each ejection heater 419 has a function of generating bubbles in the ink in the corresponding pressure chamber (not shown) to eject the ink from the ink. Figure 3 The sub-heater 418 has a function of ejecting ink from a corresponding one of the ejection orifices 36 in the print head 105. Each sub-heater 418 has a function of adjusting the temperature to stabilize the ejection characteristics of the ink. The sub-heater 418 is formed on the substrate of the print head 105 at the same time as the ejection heater 419. Alternatively, the sub-heater 418 may be attached to the print head 105. Figure 4 The head driver 414 in FIG. 4 has a function of driving the ejection heater 419 according to the print data. Specifically, the head driver 414 includes a shift register, a latch circuit, and a logic circuit element. The shift register has a function of aligning the print data with the position of the ejection heater 419. The latch circuit has a function of performing latching at an appropriate timing. The logic circuit element has a function of operating the ejection heater 419 in synchronization with the drive timing signal. (Main scanning motor driver 415; sub-scanning motor driver 416; and recovery processor 417)

[0055] The main scanning motor driver 415 has a function of driving the main scanning motor 420. The main scanning motor 420 has a function of generating a driving force for moving the carriage unit 102 including the print head 105 in the X direction. The sub-scanning motor 421 has a function of generating a driving force for conveying the print medium P in the Y direction (also referred to as the sub-scanning direction) via the conveying unit 201. The sub-scanning motor driver 416 has a function of driving the sub-scanning motor 421. The recovery processor 417 has a function of executing a recovery process for maintaining the ejection of the print head 105 in a good condition.

[0056] (Image Capturing Unit 441)

[0057] The image capturing section 441 is arranged downstream of the fixing unit 203. The image capturing section 441 has a function of capturing images of a plurality of test patterns printed on the print medium P after passing through the fixing unit 203. The image capturing section 441 includes, for example, a charge coupled device (CCD) image sensor. Alternatively, the image capturing section 441 may include a complementary metal oxide semiconductor (CMOS) image sensor. The CPU 401 may cause the RAM 403 or a storage device to store a prediction result of a prediction based on the images of the plurality of test patterns captured by the image capturing section 441 as print information. The images of the test patterns will be described in detail later.

[0058] (Display unit 442)

[0059] The display section 442 has a function of displaying information about images of a plurality of test patterns and various information about the internal conditions of the printing device, etc. The display section 442 includes, for example, a liquid crystal display. Alternatively, the display section 442 may include, for example, a plurality of LEDs, and inform the user of various information by using the flashing pattern of these LEDs. The function of the operation section 406 may be constituted by a touch panel, and a touch panel display may be constituted by stacking the touch panel on the liquid crystal display. With this structure, the function of the operation section 406 and the function of the display section 442 may be realized in one unit.

[0060] (Multi-pass printing control)

[0061] Next, we will refer to Figure 5 Description Reference Figures 1 to 4 Multi-pass printing control in a printing device is described. Figure 5 2 is a schematic diagram illustrating multi-pass printing control. The multi-pass printing control is a control for printing on a unit area 501 of the printing medium P by multiple scans using coloring ink and reaction liquid. An image is printed on the printing medium P by the multi-pass printing control. Figure 5 The example in which printing on the unit area 501 is completed by eight scans is illustrated. Figure 5 In the Y direction, Figure 3 Each of the ejection orifice arrays 31 to 35 in the unit area 501 is used to form eight ejection orifice groups A1 to A8. In each of the eight scans performed on the unit area 501, the coloring ink and the reaction liquid are ejected from the corresponding ejection orifice groups in the eight ejection orifice groups A1 to A8. During the ejection, the print medium P is actually conveyed to the downstream side in the Y direction between the scans of the print head 105. For simplicity, Figure 5The diagram illustrates a print head 105 being moved to the upstream side in the Y direction between scans of the print head 105. In the first scan, the print head 105 is scanned in a positional relationship that the ejection orifice group A1 in each ejection orifice array 31 to 35 faces the unit area 501 of the print medium P. Therefore, according to the print data assigned to the first scan, the color ink and the reaction liquid are ejected from the ejection orifice group A1 onto the unit area 501. After the first scan is finished, the print medium P is transported in the Y direction by a distance corresponding to one ejection orifice group. Then, the second scan is performed. Therefore, according to the print data assigned to the second scan, the color ink and the reaction liquid are ejected from the ejection orifice group A2 onto the unit area 501. In the subsequent third to eighth scans, the transport of the print medium P and the ejection from the print head 105 are alternately performed. In this way, the ejection from the ejection orifice groups A1 to A8 is performed in the first to eighth scans on the unit area 501. Thus, multi-pass printing is completed on the unit area 501. Needless to say, printing on other unit areas is simultaneously performed in the same manner, with different ejection orifice groups being associated with the respective other unit areas.

[0062] (Mask Pattern)

[0063] FIG. 6A to FIG. 6D is a schematic diagram for explaining a mask pattern. FIG. 6A to FIG. 6D In each mask pattern shown in , a black pixel (hereinafter also referred to as an element) indicates a pixel that allows ink ejection in the quantized data when ink ejection is specified in the quantized data. FIG. 6A to FIG. 6D In each mask pattern shown in , white pixels (elements) indicate pixels for which ink ejection is not allowed in the quantized data in the case where ink ejection is specified in the quantized data. FIG. 6A to FIG. 6D A 4-pixel × 8-pixel mask pattern is presented. By repeatedly applying FIG. 6A to FIG. 6D For each mask pattern shown in Figure 5 The processing of all unit areas 501 in FIG. Fig. 6A A mask pattern group of quantized data to be applied to the colored ink ejection orifice arrays (ie, the black ink ejection orifice array 31, the cyan ink ejection orifice array 32, the magenta ink ejection orifice array 33, and the yellow ink ejection orifice array 34) is illustrated. Fig. 6AAs shown in , regarding the color ink ejection orifice arrays 31 to 34, among the ejection orifice groups A1 to A8 assigned to the 1st to 8th scans, print enable pixels are arranged only in the mask patterns of the ejection orifice groups A2 to A8 assigned to the 2nd to 8th scans. At the same time, print enable pixels are not arranged in the mask pattern of the ejection orifice group A1 assigned to the 1st scan. Therefore, in this embodiment, the color ink is ejected only in the 2nd to 8th scans among the eight scans. On the other hand, as Figure 6B As shown in , with respect to the reaction liquid injection orifice array 35, among the injection orifice groups A1 to A8 assigned to the 1st to 8th scans, print-enabling pixels are arranged in the mask pattern of the injection orifice groups A1 to A7 assigned to the 1st to 7th scans. Then, no print-enabling pixels are arranged in the mask pattern of the injection orifice group A8 assigned to the 8th scan. Therefore, in the present embodiment, the reaction liquid is injected only in the 1st to 7th scans among the eight scans. As described above, the reaction liquid is injected onto the printing medium before the coloring ink is injected. For this reason, immediately after the coloring ink is injected onto the printing medium, the colorant in the coloring ink begins to condense with the reaction liquid. This makes it possible to appropriately reduce the seepage of the coloring ink. Alternatively, depending on the printing medium P, the mask pattern may be changed as follows Figure 6C and Fig.6D The mask pattern shown in , so that the coloring ink and the reaction liquid can be ejected simultaneously in the same print scan. In this embodiment, Fig. 6A and Figure 6B Presenting mask pattern A, and Figure 6C and Fig.6D The mask pattern B is presented. The printing medium printed with the coloring ink and the reaction liquid is conveyed and passed along the fixing unit 203, so that the ink is heated and dried. In this way, even on a non-absorbent or poorly absorbent printing medium, the ink is fixed and printing is completed.

[0064] (Ink ingredients)

[0065] Hereinafter, the composition of each ink will be described in detail. The coloring ink and the reaction liquid used in this embodiment all contain water-soluble organic solvents. From the viewpoint of wettability and moisture retention of the surface of the print head 105, the water-soluble organic solvent preferably has a boiling point of more than 150°C and less than 300°C. Particularly preferred water-soluble organic solvents include ketone compounds (such as acetone and cyclohexanone), ethylene glycol derivatives (such as tetraethylene glycol dimethyl ether), etc. In addition, other particularly preferred water-soluble organic solvents include heterocyclic compounds with lactam structures represented by N-methylpyrrolidone and 2-pyrrolidone, etc. From the viewpoint of ejection characteristics, the content of the water-soluble organic solvent is preferably more than 3% by weight and less than 30% by weight. Specific examples of water-soluble organic solvents include methanol, ethanol, n-propanol, isopropanol, n-butanol, etc. Other specific examples of water-soluble organic solvents include sec-butyl alcohol, tert-butyl alcohol, etc. These are alkyl alcohols with 1 to 4 carbon atoms. Moreover, other examples of the water-soluble organic solvent include: amides such as dimethylformamide and dimethylacetamide; ketones or ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol; or alkylene glycols having an alkylene group with 2 to 6 carbon atoms, such as propylene glycol, butanediol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexanediol and diethylene glycol; lower alkyl ether acetates such as polyethylene glycol monomethyl ether acetate; glycerol; lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl ether (or ethyl ether), diethylene glycol monomethyl ether (or ethyl ether) and triethylene glycol monomethyl ether (or ethyl ether); polyhydric alcohols such as trimethylolpropane and trimethylolethane; N-methyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, etc. The water-soluble organic solvent listed above can be used separately or as a mixture of two or more. As water, it is desirable to use deionized water. The content of the water-soluble organic solvent in the reaction solution (RCT) is not particularly limited. Meanwhile, in addition to the above-mentioned components, surfactants, defoamers, preservatives, antifungal agents, etc. can also be appropriately added to each colorant ink (C, M, Y, K) as needed to give desired physical properties.

[0066] All the coloring inks and reaction solutions used in the present embodiment all contain surfactants.Surfactant is used as a penetrant to improve the penetration of ink to the print medium dedicated to inkjet printing.As the addition amount of surfactant increases, the surfactant exerts a stronger ability to reduce the surface tension of ink, thereby improving the wetting power and penetration of ink to the print medium.In the present embodiment, by adding a small amount of acetylene glycol EO adducts etc. as surfactants to adjust each ink, the surface tension of each ink is 30dyn / cm or less, and the surface tension difference between the inks is 2dyn / cm or less.More specifically, each ink is adjusted to have a surface tension of about 28 to 30dyn / cm.Surface tension is measured by using a fully automatic surface tension meter CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).Measuring equipment is not limited to the above examples, as long as the surface tension of ink can be measured.

[0067] In the present embodiment, the pH value of each ink is stable on the alkaline side, and its value ranges from 8.5 to 9.5. In order to prevent the dissolution or degradation of the components in contact with the ink in the printing device and the print head and to prevent the solubility of the dispersed resin in the ink from decreasing, etc., the pH value of each ink is preferably above 7.0 and below 10.0. The pH value is measured by using an F-52 pH meter manufactured by Horiba Co., Ltd. The measuring device is not limited to the above examples, as long as the pH value of the ink can be measured.

[0068] Hereinafter, among the black ink, cyan ink, magenta ink, and yellow ink used in the present embodiment, the cyan ink and the magenta ink will be described in detail for the sake of simplicity.

[0069] (Magenta ink)

[0070] (Preparation of dispersion liquid)

[0071] First, using benzyl acrylate and methacrylic acid as raw materials, an AB type block polymer having an acid value of 300 and a number average molecular weight of 2500 is prepared by a conventional method, then neutralized with potassium hydroxide aqueous solution, and diluted with ion exchange water to prepare a homogeneous 50 mass % polymer aqueous solution. Then, 100g of the above-mentioned polymer solution, 100g of CI Pigment Red 122 and 300g of ion exchange water are mixed, and mechanically stirred for 0.5 hour. Next, using a microfluidizer, the mixture is processed by passing through an interaction chamber five times under a hydraulic pressure of about 70MPa. In addition, the above-mentioned dispersion obtained is centrifuged (12000rpm, 20 minutes) to remove the undispersed material including coarse particles, thereby obtaining a magenta dispersion. The pigment concentration of the magenta dispersion obtained is 10 mass % and the dispersion concentration is 5 mass %.

[0072] Next, the ink preparation of magenta ink will be described. In the ink preparation, the above-mentioned magenta dispersion is used and adjusted to a predetermined concentration by adding the following components thereto. These components are fully mixed and stirred, and then filtered under pressure through a microfilter (manufactured by FUJIFILM Corporation) having a pore size of 2.5 μm to prepare a colorant ink having a pigment concentration of 4 mass % and a dispersant concentration of 2 mass %.

[0073]

[0074] Ion exchange water (manufactured by Kawaken Fine Chemical Co., Ltd.) Balance (Cyan ink)

[0075] (Preparation of dispersion liquid)

[0076] First, using benzyl acrylate and methacrylic acid as raw materials, an AB type block polymer having an acid value of 250 and a number average molecular weight of 3000 was prepared by a conventional method, and then neutralized with an aqueous potassium hydroxide solution and diluted with ion exchange water to prepare a homogeneous 50 mass % polymer aqueous solution. Then, 180 g of the above polymer solution, 100 g of CI Pigment Blue 15:3 and 220 g of ion exchange water were mixed and mechanically stirred for 0.5 hours.

[0077] Next, using a microfluidic instrument, the mixture was processed by passing through an interaction chamber five times at a liquid pressure of approximately 70 MPa.

[0078] In addition, the dispersion obtained above was centrifuged (12000 rpm, 20 minutes) to remove undispersed matter including coarse particles, thereby obtaining a cyan dispersion having a pigment concentration of 10% by mass and a dispersion concentration of 10% by mass.

[0079] (Cyan ink)

[0080] (Ink preparation)

[0081] In the ink preparation, the above-mentioned cyan dispersion was used and adjusted to a predetermined concentration by adding the following components thereto. These components were fully mixed and stirred, and then filtered under pressure through a microfilter (manufactured by FUJIFILM Corporation) having a pore size of 2.5 μm to prepare a colorant ink having a pigment concentration of 4 mass % and a dispersant concentration of 2 mass %.

[0082]

[0083]

[0084] Ion exchange water (manufactured by Kawaken Fine Chemical Co., Ltd.) Balance

[0085] The reaction liquid used in this embodiment contains a reactive component that reacts with the pigment contained in the ink to form a coagulant or gel of the pigment. Specifically, this reactive component is a component that can destroy the dispersion stability of the ink by the action of ionic groups when mixed with the ink containing the pigment stably dispersed or dissolved in the aqueous medium on the printing medium, etc. More specifically, in this embodiment, as will be described below, glutaric acid is used.

[0086] However, it is not necessary to use glutaric acid, and any of various water-soluble organic acids can be used as the reaction component of the reaction solution. Specific examples of organic acids include oxalic acid, polyacrylic acid, formic acid, acetic acid, propionic acid, glycolic acid, malonic acid, malic acid, maleic acid, ascorbic acid, levulinic acid and succinic acid. In addition, specific examples of organic acids also include glutaric acid, glutamic acid, fumaric acid, citric acid, tartaric acid, lactic acid, pyrrolidone carboxylic acid, pyrrolone carboxylic acid and pyrrole carboxylic acid. In addition, specific examples of organic acids also include furan carboxylic acid, pyridine carboxylic acid, coumaric acid, thiophene carboxylic acid, nicotinic acid, hydroxysuccinic acid and dihydroxysuccinic acid. The content of organic acid based on the total mass of the composition contained in the reaction solution is preferably 3.0 mass % or more and 90.0 mass % or less, and more preferably 5.0 mass % or more and 70.0 mass % or less.

[0087] (Reaction solution)

[0088] (Ink preparation)

[0089] In this Example, as described above, while using glutaric acid (manufactured by Wako Pure Chemical Industries, Ltd.) as an organic acid, a reaction liquid was prepared by mixing the following components.

[0090]

[0091] Ion exchange water (manufactured by Kawaken Fine Chemical Co., Ltd.) Balance

[0092] In the printing method using the coloring ink and the reaction liquid, the same area is printed with the coloring ink of the required volume and the reaction liquid of the required volume. Therefore, the reaction liquid contacts the coloring ink at a certain frequency. This can make it possible to obtain the effect of preventing seepage, which may otherwise occur particularly obviously on non-absorbent media. The print medium printed with the coloring ink and the reaction liquid is conveyed and passed along the fixing unit 203, so that the ink is heated and dried. In this way, even on non-absorbent or poorly absorbent print media, the ink is fixed and printing is completed.

[0093] (Print Media)

[0094] The printing device in this embodiment can print multiple types of print media. The printable print media P in this embodiment can be roughly classified into three types. The first type is a non-absorbent print medium that cannot be penetrated by the water contained in the colored ink. The second type is a poorly absorbent print medium with low absorbency of the water contained in the colored ink. The third type is a print medium suitable for inkjet printing with high water absorbency.

[0095] Figure 7 is a schematic diagram illustrating a user interface (UI) for print media selection. Figure 7 4 is a view schematically illustrating a screen (UI) provided on a display of a host device 404 for a user to input information about the type of print medium. Figure 7In the example, eight types of printing media are shown: "PVC film", "PVC banner", "PP film", "synthetic paper", "plain paper", "glossy paper", "art paper", "coated paper" and "wallpaper". Among them, "PVC film", "PVC banner", "PP film" and "synthetic paper" are printing media that are less likely to be penetrated by moisture contained in the coloring ink. An example of "synthetic paper" is "Yupo (registered trademark)". There are printing media with a plastic layer coated on the outermost surface of the substrate, printing media on which an ink receiving layer is not formed on the substrate, and sheets, films, banners, etc. made of glass, synthetic paper, plastic, etc. Examples of the above-mentioned coated plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc. These printing media with low absorbency are excellent in water resistance, light resistance and scratch resistance, and are therefore generally used for printing prints intended for outdoor exhibitions. At the same time, "glossy paper", "art paper" and "coated paper" are highly absorbent printing media suitable for inkjet printing that allow moisture contained in the coloring ink to penetrate. These print media are not as good as print media with low absorbency in terms of water resistance, light resistance and scratch resistance, but due to the ability to absorb the coloring ink applied in the ink receiving layer, the color development is excellent, so printing with high image quality can be achieved. For this reason, these print media are generally used to print prints intended for indoor exhibitions. These print media have such high absorbency that the coloring ink is allowed to penetrate into the print medium before contacting each other, thereby not requiring a reaction liquid. Meanwhile, "plain paper" and "wallpaper" are classified as print media that absorb water slowly and are difficult to absorb because their surface layers are made of pulp materials or have coatings. On the print medium that is difficult to absorb, the coloring inks contact each other before the coloring inks are absorbed in the print medium, and the seepage of the coloring ink occurs. For this reason, on the print medium that is difficult to absorb, the reaction liquid also prevents the seepage of the coloring ink. In order to classify the print medium into a print medium that is difficult to absorb and a non-absorbent print medium, the liquid transfer volume Vt per unit time is used as an index to quantify the "absorbency" of the print medium. One method for measuring the liquid transfer volume Vt is the "Bristow method", which measures the volume of water absorbed within a short time after contact with water. In the Bristow method, a certain volume of liquid V is placed in a container with a small opening, the area wL of the portion of the paper surface to which the liquid is transferred is measured when the opening is in contact with the paper surface, and then the liquid transfer volume Vt per unit time is calculated according to the formula Vt = V / wL.

[0096] (Wettability)

[0097] However, measuring the volume of ink transferred to the print medium requires the use of a device dedicated to Bristow measurement, and it is difficult to incorporate such a device into a general printing device. In addition, regardless of whether the print medium is a non-absorbent print medium into which moisture contained in the coloring ink is unlikely to penetrate or a poorly absorbent print medium having low absorbency for moisture contained in the coloring ink, the surface tension of the coloring ink applied to the print medium varies depending on the surface energy of the surface layer of the print medium. For this reason, the print medium P is classified into a print medium P having an easy-wetting property and a print medium P having a poor-wetting property. An index for quantifying the "wettability" of the print medium is the "contact angle" (θ: contact angle). FIG. 8A to FIG. 8C It is a graph used to illustrate the quantification of the “wettability” of the printing medium. Fig. 8A An example of parameters used to determine the contact angle θ, which is the angle between the tangent line of a liquid droplet and the solid surface, is shown in FIG. Fig. 8A As shown in , the contact angle θ is referred to as the “contact angle” and can be calculated according to Young's equation γs=γL·cosθ+γsL. Figure 8B : is a diagram illustrating a print medium P having an easy-wetting property. The print medium P having an easy-wetting property has a small contact angle θ, and allows wetting and spreading with an applied liquid such as a coloring ink. Figure 8C is a diagram illustrating a print medium P having a difficult-to-wet property. The print medium P having a difficult-to-wet property has a large contact angle θ, and does not allow wetting spread with an applied liquid such as a coloring ink. However, measuring the contact angle θ as the angle between the print medium P and the coloring ink requires the use of a dedicated contact angle meter, and it is difficult to incorporate such a dedicated contact angle meter into a general printing device. In the case of using a pre-registered print medium, "absorbency" or "wettability" can be collected in advance, and a printer unit suitable for the "absorbency" or "wettability" can be prepared and provided in advance.

[0098] (Classification of Print Media)

[0099] Fig. 9: is a diagram for explaining the classification of printing media according to the "absorbency" and "wettability" of the printing media. As described above, "absorbency" is classified according to the base material or coating, and "glossy paper", "art paper" and "coated paper" are classified as printing media suitable for inkjet printing. Then, "plain paper" and "wallpaper" are classified as poorly absorbent printing media. In addition, "PVC film", "PVC banner", "PP film" and "synthetic paper" are classified as non-absorbent printing media. Meanwhile, regarding "wettability", the "wettability" of the printing media may vary greatly depending on processing conditions, material formulations, etc. For example, among the non-absorbent printing media, "PVC film", "PVC banner" and "PP film" are classified as printing media P with poorly wettable properties because they have relatively large contact angles. Meanwhile, "synthetic paper" is classified as printing media P with easy wettable properties because it has a relatively small contact angle. In this way, the wettability of the printing media varies greatly. For this reason, it is difficult to predict the wettability of a printing medium that has not been registered in advance.

[0100] (Drying conditions)

[0101] Fig.10 is a diagram used to illustrate drying conditions. Fig.10 As specified in , the drying condition includes a first drying condition and a second drying condition. The first drying condition includes an air blowing setting that causes a control to prevent the air supply from being stopped. The second drying condition includes an air blowing setting that causes a control to perform the air supply. Under the first drying condition and the second drying condition, the platen blower unit 202 is responsible for the air supply. However, the air supplier may be any device other than the platen blower unit 202. The device is not particularly limited as long as it can evaporate the moisture in the ink on the printing medium P.

[0102] The first drying condition includes at least one of a blowing setting, a temperature setting, and an air flow speed setting. Fig.10 In the example of , the first drying condition is set to the blowing setting "off", the temperature setting "off", and the air flow speed setting "off". Fig.10 In the example of , like the first drying condition, the second drying condition includes at least one of a blowing setting, a temperature setting, and an air flow speed setting. Fig.10In the example of , the second drying condition is set to the blowing setting "on", the temperature setting "30°C", and the air flow speed setting "3m / s". The drying condition may also include an air flow volume setting. For example, as the rotation speed of the fan 202A increases, the air flow volume blown out from the fan 202A increases. Therefore, the air flow volume may be set by using the rotation speed of the fan 202A. Here, as the air flow volume increases, the amount of ink mist may increase. In order to solve this problem, in the case of increasing the air flow volume by increasing the rotation speed of the fan 202A, the rotation speed of the air curtain fan 205A may also be increased. Alternatively, a drying condition (third drying condition) that is more powerful than the second drying condition may be added. For example, the third drying condition may be set to the blowing setting "on", the temperature setting "35°C", and the air flow speed setting "6m / s".

[0103] (Test Pattern)

[0104] Fig.11 is a diagram for explaining a test pattern. Fig.11 In [pl / dpi], the unit is the volume of the droplet per unit area. Fig.11 In the example of , [pl / 600dpi] is used. This means that the unit area is a line of 1 inch (about 2.54cm) where 600 droplets can be placed. That is, the density of the volume of the droplets is 600 droplets per inch. Fig.11 The letter "A" is shown as an example of a test pattern. The latter "A" is composed of a coloring ink and a reaction liquid. As a colorant contained in the coloring ink, black ink is used. The volume of the black ink per unit area is 36 [pl / 600dpi]. As the reaction liquid volume, Fig.11 As shown in, five levels (a), (b), (c), (d) and (e) were tried. The volume of the reaction liquid per unit area (a) is 0 [pl / 600dpi]. The volume of the reaction liquid per unit area (b) is 5 [pl / 600dpi]. The volume of the reaction liquid per unit area (c) is 10 [pl / 600dpi]. The volume of the reaction liquid per unit area (d) is 15 [pl / 600dpi]. The volume of the reaction liquid per unit area (e) is 20 [pl / 600dpi]. Fig.11 The test pattern shown in the Figure 6BThe mask pattern A in is printed by applying the reaction liquid volumes (a) to (e) to the corresponding five letters "A" by multi-pass printing while printing five letters "A" on the print medium P. In the case of forming images of multiple test patterns as described above, it is possible to determine which reaction liquid volume causes the diffusion of the coloring ink based on the image of the test pattern. Specifically, it is checked whether the coloring ink diffuses beyond the boundary between the area printed with the coloring ink and the area not printed with the coloring ink. If the coloring ink diffuses beyond this boundary, the image printed with the coloring ink bleeds. Therefore, it is possible to visually check whether bleeding occurs.

[0105] (No air blowing (first drying condition); difficult to wet (low wettability))

[0106] Fig.12 is a diagram illustrating the printing result of a test pattern on a printing medium having a difficult-to-wet property under a first drying condition. Specifically, Fig.12 Presented in Fig.10 The first drying condition is Figure 8C Printing on a printing medium having a difficult-to-wet property as shown in Fig.11 Results for all test patterns in . Fig.12 The images (a) to (e) in FIG. Fig.11 Images printed under the conditions specified in (a) to (e) of Fig.11 The image under conditions (a) and (b) Fig.12 The images (a) and (b) in FIG. 1 indicate that the reaction liquid volume is insufficient to cause the coloring ink to coagulate. For this reason, the letter "A" oozes out. In addition, in the case where the reaction liquid volume is 10 [pl / 600dpi] or more, Fig.11 The images under conditions (c), (d) and (e) Fig.12 In images (c), (d), and (e), the letter “A” does not bleed through.

[0107] (No air blowing (first drying condition); easy to wet (high wettability))

[0108] Fig.13 is a diagram illustrating the printing result of a test pattern on a printing medium having an easy-wetting property under a first drying condition. Specifically, Fig.13 Presented in Fig.10 Under the first drying condition in Figure 8B Printing on the print media with easy wetting properties shown in Fig.11 Results for all test patterns in . Fig.13 The images (a) to (e) in FIG. Fig.11 Images printed under the conditions specified in (a) to (e) of Fig.11The image under conditions (a) to (e) Fig.13 In all images (a) to (e) of FIG. 1 , wetting with the pigmented ink is seen to spread from the letter "A". Fig.13 In all images (a) to (e), the phenomenon of ink spreading beyond the predetermined position occurs.

[0109] (with air blowing (second drying condition); easy to wet (high wettability))

[0110] Fig.14 is a diagram illustrating the printing result of a test pattern on a print medium having an easy-to-wet property under air blowing. Specifically, Fig.14 Presented in Fig.10 Under the second drying condition in Figure 8B Printing on the print media with easy wetting properties shown in Fig.11 Results for all test patterns in . Fig.14 The images (a) to (e) in FIG. Fig.11 The image is printed under the conditions specified in (a) to (e) of Fig.11 The images under conditions (a) to (c) in Fig.14 In each of the images (a) to (c), wetting with the colored ink is seen to spread beyond the letter "A". Fig.14 In the images (a) to (c) in FIG. 1 , the ink spreads beyond the predetermined position. On the other hand, in the images (a) to (c) in FIG. 1 , the ink spreads beyond the predetermined position. Fig.11 The image under conditions (d) and (e) Fig.14 In images (d) and (e), no diffusion from the letter "A" occurs.

[0111] (Operation example)

[0112] Fig.15 is a flowchart presenting a process of determining drying conditions and a reaction liquid volume according to the first embodiment of the present disclosure. Fig.15 The processing presented in FIG. 4 is realized by the CPU 401 reading out a program for realizing various control modules stored in the ROM 402 into the RAM 403 and executing the program. Fig.15 Some or all of the functions in the steps of may be implemented by hardware (such as ASIC or electronic circuit). The symbol "S" in the description of each process indicates a step in this flowchart.

[0113] In response to the user inputting a test pattern printing start instruction to the printing device, the Fig.15 The processing presented in .

[0114] In S1501, the CPU 401 causes air blowing under a first drying condition. The first drying condition is applied to the platen blower unit 202. Specifically, Fig.10 As presented in , the CPU 401 sets "air blowing setting: off", "temperature setting: off" and "air flow speed setting: off" in the platen blower unit 202. In short, the platen blower unit 202 will not supply air. In S1502, the CPU 401 prints a test pattern under the first drying condition. Specifically, the CPU 401 causes the print head 105 to print the test pattern while preventing the platen blower unit 202 from supplying air. In S1503, the CPU 401 conveys the print medium to the fixing unit 203 to dry and fix the printed image of the test pattern, thereby fixing the image. In S1504, the CPU 401 makes a notification of the completion of printing on the print medium after the fixing in S1503 is completed. This notification can be made by the display unit 442. Alternatively, the notification can be made by the display of the host device 404. Alternatively, the notification can be issued to a smart phone or the like owned by the user. In S1505, the CPU 401 determines whether the user's input is received. Herein, it is assumed that the user's input is an input notifying whether there is an image without any image defects. If it is determined that the user's input is received, the CPU 401 proceeds from the processing in S1505 to the processing in S1506. On the other hand, if it is determined that the user's input has not been received, the CPU 401 continues the processing in S1505.

[0115] In S1506, the CPU 401 performs the following operations based on the information input by the user in S1505. Fig.12 to determine whether there is an image without any image defects. Fig.12 If the printing result of the test pattern in determines that there is an image without any image defects, the CPU 401 proceeds from the processing in S1506 to the processing in S1507. Fig.12 As presented in FIG. 1 , on the print medium on which the test pattern is printed, the color ink spreads in the case where the reaction liquid volume is 0 [pl] and 5 [pl], and the color ink does not spread in the case where the reaction liquid volume is 10 [pl], 15 [pl], and 20 [pl]. This is just an example and does not Fig.12 Specifically, the user can visually determine the printing medium with a difficult-to-wet property. Fig.12 In the images (a) to (e) Fig.12 The images (c), (d) and (e) in FIG. 4 are images without any image defects. Therefore, the user inputs the option "Yes" from the user interface provided in the printing device body or the host device 404. On the other hand, if Fig.13 If the printing result of the test pattern in determines that there is no image without any image defects, the CPU 401 proceeds from the processing in S1506 to the processing in S1509. In this case, Fig.13 As presented in FIG. 1 , on the print medium on which the test pattern was printed, the colored ink spread in all cases where the reaction liquid volume was 0 [pl] to 20 [pl]. This is only an example and does not Fig.13 Specifically, the user can visually determine Fig.13 There is no image without any image defect among the images (a) to (e) in FIG. 4. Therefore, the user selects “No” from the user interface input provided in the printing apparatus main body or the host apparatus 404.

[0116] In S1507, the CPU 401 sets the drying condition to Fig.10 404. The first drying condition in S1507 is set and the processing proceeds from S1507 to S1508. Specifically, the CPU 401 automatically sets the drying condition based on the first drying condition of "blowing setting: off", "temperature setting: off" and "air flow speed setting: off". Alternatively, if the first drying condition is input by the user from a user interface provided in the printing device body or the host device 404, the CPU 401 performs the following processing. Specifically, in the printing device body or the host device 404, the CPU 401 sets the drying condition based on the input first drying condition. Through this operation, the air supply based on the first drying condition is set in the platen blower unit 202. In other words, the first drying condition including the blowing setting that prevents the platen blower unit 202 from supplying air is set.

[0117] In S1508, the CPU 401 will Fig.12 The reaction liquid volume (c) of the minimum liquid volume among the images (c), (d) and (e) without any image defects is set as the ejection reaction liquid volume. The setting method can be implemented based on the information about the reaction liquid volume contained in the user input from the user interface provided in the printing device body or the host device 404. In the printing device body or the host device 404, the CPU 401 sets the ejection reaction liquid volume based on the input information about the reaction liquid volume. Through the operations specified in the above flowchart, the drying conditions and reaction liquid volume for printing on the print medium with a difficult-to-wet property are determined.

[0118] according to Fig.15In the above flowchart, after the test pattern printing under the first drying condition in S1502, the process of determining whether there is an image without any image defects in S1506 is performed. Therefore, if there is an image without any image defects in the determination in S1506, the CPU 401 can determine the drying condition and the reaction liquid volume without causing the test pattern to be printed under the second drying condition. Therefore, efficient processing can be achieved.

[0119] In S1509, the CPU 401 causes air blowing under the second drying condition. The second drying condition is applied to the platen blower unit 202. Specifically, Fig.10 As presented in , the CPU 401 sets "air blowing setting: on", "temperature setting: 30°C", and "air flow speed setting: 3m / s" in the platen blower unit 202. In short, the platen blower unit 202 will supply air. In particular, the platen blower unit 202 will supply heated air. In S1510, the CPU 401 prints a test pattern under the second drying condition. Specifically, the CPU 401 causes the print head 105 to print a test pattern while causing the platen blower unit 202 to supply heated air. In S1511, the CPU 401 conveys the print medium to the fixing unit 203 to dry and fix the printed image for the test pattern, thereby fixing the image. In S1512, the CPU 401 notifies that printing on the print medium is completed after the fixing in S1511 is completed. This notification can be performed in the same manner as in S1504.

[0120] In S1513, the CPU 401 sets the drying condition to Fig.10 , and proceeds from the processing in S1513 to the processing in S1514. Specifically, the CPU 401 automatically sets the drying condition based on the second drying condition of "air blowing setting: on", "temperature setting: 30°C", and "air flow speed setting: 3m / s". Alternatively, if the second drying condition is input by the user from a user interface provided in the printing device body or the host device 404, the CPU 401 performs the following processing. Specifically, in the printing device body or the host device 404, the CPU 401 sets the drying condition based on the input second drying condition. Through this operation, the air supply based on the second drying condition is set in the platen blower unit 202. In other words, the second drying condition including the air blowing setting that causes the platen blower unit 202 to supply air is set.

[0121] In S1514, CPU 401 will act as Fig.14The reaction liquid volume (d) of the smaller liquid volume between the image (d) without any image defects and the reaction liquid volume in (e) is set as the ejection reaction liquid volume. This setting method can be implemented based on information about the reaction liquid volume in the user input from the user interface provided in the printing device body or the host device 404. In the printing device body or the host device 404, the CPU 401 sets the ejection reaction liquid volume based on the input information about the reaction liquid volume. Through the operations specified in the above flowchart, the drying conditions and reaction liquid volume for printing on the print medium with easy wettability are determined.

[0122] according to Fig.15 According to the above flowchart in S1506, if there is no image without any image defects in the determination of S1506, the CPU 401 causes the test pattern to be printed under the second drying condition, and the drying condition and the reaction liquid volume can be determined based on the test pattern. The test pattern is printed under the second drying condition in which the drying condition is changed from the first drying condition. According to the above, if there is no image without any image defects under the first drying condition, the test pattern can be printed again. In this operation, the test pattern printing under the second drying condition involving heating the air is performed only when necessary, so that the power required for heating the air is not consumed wastefully.

[0123] Furthermore, the platen blower unit 202 blows heated air toward the surface of the print medium having an easily wettable property during printing. This operation promotes the evaporation of water contained in the ink and promotes the fixing of the ink, thereby making it possible to prevent image defects due to the ink diffusion phenomenon. Furthermore, the minimum liquid volume is determined as the reaction liquid volume for preventing image defects, which makes it possible to reduce the waste of the reaction liquid volume.

[0124] For the print medium with a property that is difficult to wet, the platen blower unit 202 does not blow heated air toward the surface of the print medium during printing, which can make it possible to prevent image defects caused by the generation of streaking unevenness that may occur due to accelerated drying. Specifically, since the print medium with a property that is difficult to wet has the following characteristics: Figure 8C The large contact angle θ shown in , therefore, the ink droplets tend not to spread along the surface of the print medium. Here, it is assumed that the ink is a coloring ink mixed with a reaction liquid ink. Figure 8CWhen the heated air is blown out in a state, the moisture in the ink droplets evaporates while preventing the ink droplets from spreading over the surface of the printing medium. As the moisture in the ink droplets evaporates, the ratio of the synthetic resin particles in the reaction liquid to the moisture in the ink droplets increases. For this reason, the ink droplets begin to form a film on their surface without spreading over the surface of the printing medium. At the same time, a portion of the blown air passes along the surface of the droplets and forms stripes. Therefore, from a whole perspective, multiple droplets of ink in the form of a film are dispersed on the printing medium, resulting in an overall uneven state. This causes the occurrence of the stripe unevenness phenomenon. In order to solve this problem, according to Fig.15 In the processing of the flowchart, the blowing control under the first drying condition is first performed. In other words, the platen blower unit 202 is prevented from blowing the heated air toward the platen 104. Through this operation, even if the printing medium has a difficult-to-wet property, the occurrence of the stripe unevenness phenomenon can be avoided, thereby preventing image defects due to the stripe unevenness phenomenon. At the same time, even if the printing medium has an easy-to-wet property and there is no image in which the colored ink does not spread under the first drying condition, the blowing control under the second drying condition is performed. This also makes it possible to print an image in which the colored ink does not spread even on a printing medium with an easy-to-wet property, thereby preventing image defects due to the ink diffusion phenomenon on a printing medium with an easy-to-wet property. Therefore, it is possible to obtain a high-quality image.

[0125] Here, even in S1512, there is a possibility that there is no image without any image defects on the print medium. In this case, air blowing may be performed under a third drying condition for drying that is stronger than the second drying condition. For example, the third drying condition may be set to an air blowing setting of "on", a temperature setting of "35°C", and an air flow speed setting of "6m / s". The CPU 401 causes air blowing under the third drying condition. The third drying condition is applied to the platen blower unit 202. The CPU 401 prints a test pattern under the third drying condition. The CPU 401 conveys the print medium to the fixing unit 203 to dry and fix the printed image for the test pattern, thereby fixing the image. In this case, the third drying condition is set instead of the second drying condition. The reaction liquid volume is determined based on the test pattern under the third drying condition.

[0126] (First Modification: Automatic Determination by Similarity Calculation)

[0127] Fig.16 is a flowchart presenting a first variation of the process of determining the drying conditions and the reaction liquid volume for printing according to the first embodiment of the present disclosure. Fig.16The processing presented in FIG. 4 is realized by the CPU 401 reading out a program for realizing various control modules stored in the ROM 402 into the RAM 403 and executing the program. Fig.16 Some or all of the functions in the steps of may be implemented by hardware (such as ASIC or electronic circuit). The symbol "S" in the description of each process indicates a step in this flowchart.

[0128] In response to the user inputting a test pattern printing start instruction to the printing device, the Fig.16 The processing shown in .

[0129] Fig.16 The processing presented in is for the case where determinations regarding a test pattern printed on a print medium are made automatically through pattern matching. Fig.16 The processing in S1601 to S1603 and S1607 to S1615 is the same as Fig.15 The processes in S1501 to S1503 and S1506 to S1514 are the same. Therefore, the description thereof is omitted herein.

[0130] In S1604, the CPU 401 determines whether the test pattern is printed on the print medium. If it is determined that the test pattern is printed, the CPU 401 proceeds from the processing in S1604 to the processing in S1605. On the other hand, if it is determined that the test pattern is not printed, the CPU 401 continues the processing in S1604. In order to make the determination in S1604, the reflective optical sensor 107 only needs to be arranged downstream of the fixing unit 203. As described above, the reflective optical sensor 107 is capable of detecting the density of the pattern printed on the print medium P as optical reflectivity. Therefore, it is possible to determine whether the pattern is printed on the print medium based on the density of the pattern. In S1605, the CPU 401 causes the image capture unit 441 to capture the image of the test pattern printed on the print medium. This operation makes the test pattern available as captured image data, so that the captured image data can be used in the pattern matching described below. In S1606, the CPU 401 calculates the similarity of each captured image result with the test pattern in the ideal image state without image defects. Specifically, the CPU 401 causes a test pattern in an ideal image state without image defects to be pre-stored as ideal data. This makes it possible to calculate the similarity between the captured image data and the ideal data. The similarity can be calculated by using a specific pattern matching algorithm. For example, the similarity between the pixel values ​​of the captured image data and the pixel values ​​of the ideal data as the template image can be calculated by using the sum of squared differences (SSD). Alternatively, the difference between the features of the ideal data and the features of the captured image data can be calculated using a scale-invariant feature transform (SIFT). By adding the processing in S1604 to S1606 as described above, it is possible to automatically determine whether there is an image without any image defects without visual inspection by the user. (Second variant: automatic determination by a machine learning model)

[0131] Fig.17 is a flowchart presenting a second modification example of the process of determining the drying conditions and the reaction liquid volume for printing according to the first embodiment of the present disclosure. Fig.17 The processing presented in FIG. 4 is realized by the CPU 401 reading out a program for realizing the control module stored in the ROM 402 into the RAM 403 and executing the program. Fig.17 Some or all of the functions in the steps in the flowchart may be implemented by hardware (such as an ASIC or an electronic circuit). The symbol "S" in the description of each process indicates a step in this flowchart.

[0132] In response to the user inputting a test pattern printing start instruction to the printing device, the Fig.17 Processing presented in .

[0133] Fig.17The processing presented in is for the case where determinations regarding a test pattern printed on a print medium are made automatically based on a machine learning model. Fig.17 The processing in S1701 to S1703 and S1707 to S1715 is the same as Fig.15 The processing in S1501 to S1503 and S1506 to S1514 is the same. In addition, Fig.17 The processing in S1704 and S1705 is the same as Fig.16 The processing in S1604 and S1605 is the same. Therefore, the description thereof is omitted herein.

[0134] In S1706, CPU 401 makes a determination about the captured image result based on the machine learning model. Specifically, it is only necessary to pre-train the machine learning model by using a plurality of expected test patterns, and compare the captured image data with the learning data obtained thereby. Any learning data obtained thereby can be used. More specifically, in the case of using a support vector machine as a learning algorithm, a hyperplane can be obtained. For example, a hyperplane is obtained in advance to distinguish the distribution of pixel values ​​of the coloring ink diffusion beyond the boundary from the distribution of pixel values ​​of the coloring ink not diffused beyond the boundary. Whether there is an image defect can be determined based on whether the distribution of pixel values ​​included in the captured image information can be classified as the distribution of pixel values ​​of the coloring ink diffusion and the distribution of pixel values ​​of the coloring ink not diffused by using a hyperplane as a boundary. The learning algorithm can be other known algorithms, such as neural networks or deep learning, for example. In addition, since it is necessary to determine whether there is bleeding of the image, it is preferred to create learning data by emphasizing the outline of each object, extracting the area of ​​the object, etc. as needed. By adding the processing in S1704 to S1706 as described above, it is possible to automatically determine whether there is an image without any image defects without visual inspection by the user.

[0135] <<Second Embodiment>>

[0136] In a second embodiment of the present disclosure, a process of printing a test pattern while changing the drying conditions for the platen blower unit 202 and determining the optimal drying conditions and the optimal reaction liquid volume based on the printed image will be described. In the first embodiment, after the test pattern printing under the first drying condition, if there is no image without any image defects, then the test pattern printing under the second drying condition is performed. The second embodiment is different from the first embodiment in that, after the test pattern printing under the first drying condition, the process includes performing the test pattern printing under the second drying condition without determining whether there is an image without any image defects, and then determining whether there is an image without any image defects. The description of the same matters as those in the first embodiment is omitted herein.

[0137] (Operation example)

[0138] Fig.18 is a flowchart presenting a process of determining drying conditions and a reaction liquid volume according to a second embodiment of the present disclosure. Fig.18 The processing presented in FIG. 4 is realized by the CPU 401 reading out a program for realizing various control modules stored in the ROM 402 into the RAM 403 and executing the program. Fig.18 Some or all of the functions in the steps of may be implemented by hardware (such as ASIC or electronic circuit). The symbol "S" in the description of each process indicates a step in this flowchart.

[0139] In response to the user inputting a test pattern printing start instruction to the printing device, the Fig.18 Processing presented in .

[0140] Fig.18 The flowchart in contains Fig.15 The processes included in the flowcharts are the same processes, but the sequence of the processes - that is, the order of the processes - is partially different. Specifically, Fig.18 The processing in S1801 to S1804 is the same as Fig.15 The processing in S1501 to S1504 is the same. Fig.18 The processing in S1805 to S1808 is the same as Fig.15 The processing in S1509 to S1512 is the same. Fig.18 The processing in S1809 and S1810 is the same as Fig.15 Although S1810 and S1506 are described in different ways, they actually include the same processing. Fig.18 The processing of S1811 and S1812 is the same as Fig.15 The processing in S1507 and S1508 is the same. Fig.18 The processing of S1813 and S1814 is the same as Fig.15 The processing in S1513 and S1514 is the same.

[0141] In other words, Fig.18In the process presented in , the test pattern printing under the first drying condition is performed on the printing medium, and then the test pattern printing under the second drying condition is performed on the printing medium. After that, for the test pattern printed under the first drying condition, it is determined whether there is an image without any image defects. According to this operation, the test pattern printing under the first drying condition and the test pattern printing under the second drying condition can be performed continuously. Therefore, even if there is no image without any image defects for the test pattern under the first drying condition, the test pattern under the second drying condition has been printed on the printing medium. Therefore, the test pattern under the second drying condition can be selected. At the same time, even if there is an image without any image defects for the test pattern under the first drying condition, the test pattern under the second drying condition has been printed on the printing medium. However, the advantage is that the process can be performed without changing the general sequence of test pattern printing, test pattern determination, and setting of drying conditions.

[0142] As described above, in the present embodiment, the test pattern printing under the first drying condition and the test pattern printing under the second drying condition can be performed continuously. After that, for the printing medium having a difficult-to-wet property, the drying condition and the volume of the reaction liquid for preventing the image defect are determined based on the printing result of the test pattern under the first drying condition. Then, for the printing medium having an easy-to-wet property, the drying condition and the volume of the reaction liquid for preventing the image defect can be determined based on the printing result of the test pattern under the second drying condition.

[0143] In the second embodiment, as described above, the test pattern printing under the second drying condition is always performed. Therefore, for a print medium with an easy-to-wet property, the dryer unit blows heated air toward the surface of the print medium during printing. This operation can make it possible to promote the evaporation of the moisture contained in the ink and promote the fixing of the ink. In addition, it can also be possible to prevent image defects caused by the ink diffusion phenomenon. In addition, the minimum liquid volume is determined as the reaction liquid volume for preventing image defects, which can make it possible to reduce the wasteful consumption of the reaction liquid volume. In the second embodiment, the test pattern printing under the first drying condition and the test pattern printing under the second drying condition are performed separately. For this reason, even on a print medium with a difficult-to-wet property, the test pattern is printed under the first drying condition, and a process that does not involve blowing heated air toward the surface of the print medium by the dryer unit during printing is also performed. This can make it possible to set a drying condition and a reaction liquid volume suitable for preventing image defects caused by the generation of streaking unevenness that may occur due to accelerated drying.

[0144] <<Third Embodiment>>

[0145] In the first and second embodiments of the present disclosure, a description was given of a process for determining a reaction liquid volume for preventing a phenomenon in which a single color ink spreads on a print medium. In a third embodiment of the present disclosure, a description will be given of a process for determining a reaction liquid volume for preventing a phenomenon in which a single color ink spreads on a print medium and further preventing a bleeding phenomenon that may occur between different color inks. In the third embodiment, descriptions of matters that are the same as those in the first and second embodiments will be omitted.

[0146] (Test Pattern)

[0147] Fig.19 A diagram for explaining a test pattern. Fig.19 An example of an image printed on a printing medium by ejecting a reaction liquid is illustrated, the image being synthesized by superimposing a letter image "A" for a second coloring ink on a background image for a first coloring ink. For example, yellow ink is used as the first coloring ink. For example, black ink is used as the second coloring ink. For both the yellow ink and the black ink, the ink volume per unit area is a predetermined volume of 36 [pl / 600dpi]. On the other hand, as the reaction liquid volume, five levels of liquid volume (f) to (j) were tried as test patterns. The reaction liquid volumes per unit area (f) to (j) are 0 [pl / 600dpi], 5 [pl / 600dpi], 10 [pl / 600dpi], 15 [pl / 600dpi], and 20 [pl / 600dpi], respectively. Specifically, using Fig.19 Each of the five levels of reaction liquid volume (f) to (j) in Figure 5 Under the multi-pass printing control in Figure 6B The test pattern is printed using the mask pattern for the reaction liquid. Figure 6B and Fig.6D Same as above, so Fig.6D The mask pattern in can be used as a mask pattern for the reaction liquid.

[0148] (Overview of operation)

[0149] As a flowchart for explaining the process of determining the drying conditions and the volume of the reaction liquid for printing in this embodiment, the flowchart of the first embodiment is used. Fig.15 and the second embodiment Fig.18 . The first coloring ink is not limited to yellow ink. For example, the first coloring ink may be magenta ink. The second coloring ink is also not limited to black ink. For example, the second coloring ink may be cyan ink. (No air blowing (first drying condition); difficult to wet (low wettability))

[0150] Fig. 20is a graph showing the printing result of a test pattern on a printing medium having a difficult-to-wet property under a first drying condition. Specifically, Fig. 20 Presented in Fig.10 Under the first drying condition in Figure 8C Printing on a printing medium having a difficult-to-wet property as shown in Fig.11 and Fig.19 The results of the test pattern in . Fig. 20 Images (a) to (e) in the figure show the Fig.12 The same results as in (a) to (e). Fig. 20 Images (f) to (j) in FIG. 1 show the newly added Fig.19 The results of the test pattern in . Fig. 20 Images (c) to (e) are images where ink diffusion does not occur. Fig. 20 Images (h) to (j) in FIG. 1 are images in which no bleeding occurs between inks of different colors. That is, Fig. 20 The images (h) to (j) in FIG. 1 are images in which there is no bleeding between a coloring ink containing a coloring agent and another coloring ink containing another coloring agent different from the aforementioned coloring agent.

[0151] (Operation example)

[0152] A flowchart using the first embodiment ( Fig.15 A description of the situation presented in the process). Fig.15 In S1506 of the embodiment, the CPU 401 determines that there is an image without any image defects. The CPU 401 proceeds from the processing in S1506 to the processing in S1507. In S1507, the CPU 401 sets the first drying condition as the drying condition. Specifically, the CPU 401 sets "air blowing setting: off", "temperature setting: off", and "air flow speed setting: off" as the drying condition. In S1508, the CPU 401 selects Fig. 20 (c) to (e) and Fig. 20 (h) to (j) in FIG. 4 are images without any image defects. Next, CPU 401 uses Fig. 20 Test patterns (c) to (e) and Fig. 20 The reaction liquid volumes (c) and (h) of the smallest liquid volumes among the reaction liquid volumes in the two types of images without any image defects in the test patterns (h) to (j) in the image are set as the ejection reaction liquid volumes. The CPU 401 sets information on the ejection reaction liquid volumes based on information in user input from a user interface provided in the printing device body or the host device 404.

[0153] (Operation example)

[0154] A flowchart using the second embodiment ( Fig.18 A description of the situation presented in the process). Fig.18 In S1810, the CPU 401 determines that there is an image without any image defects. The CPU 401 proceeds from the processing in S1810 to the processing in S1811. In S1811, the CPU 401 sets the first drying condition as the drying condition. Specifically, the CPU 401 sets "air blowing setting: off", "temperature setting: off", and "air flow speed setting: off" as the drying condition. In S1812, the CPU 401 selects Fig. 20 (c) to (e) and Fig. 20 (h) to (j) in FIG. 4 are images without any image defects. Next, the CPU 401 uses Fig. 20 Test patterns (c) to (e) and Fig. 20 The reaction liquid volumes (c) and (h) of the smallest liquid volumes among the reaction liquid volumes in the two types of images without any image defects in the test patterns (h) to (j) in the image are set as the ejection reaction liquid volumes. The CPU 401 sets information on the ejection reaction liquid volumes based on information included in the user input from the user interface provided in the printing device body or the host device 404.

[0155] (No air blowing (first drying condition); easy to wet (high wettability))

[0156] Fig.21 is a diagram illustrating the printing result of a test pattern on a printing medium having an easy-wetting property under a first drying condition. Specifically, Fig.21 Presented in Fig.10 The first drying condition is Figure 8B Printing on the print media with easy wetting properties shown in Fig.11 and Fig.19 The results of the test pattern in . Fig.21 Images (a) to (e) in the figure show the Fig.13 The same results as in (a) to (e). Fig.21 Images (f) to (j) in FIG. 1 show the newly added Fig.19 The results of the test pattern in . Fig.21 The images (a) to (e) in FIG. 1 do not include images in which the ink diffusion phenomenon does not occur, and all images are images in which the ink diffusion phenomenon occurs. Fig.21 Images (h) to (j) in FIG. 1 are images in which no bleeding occurs between different coloring inks. That is, Fig.21 The images (h) to (j) in FIG. 1 are images in which there is no bleeding between a coloring ink containing a coloring agent and another coloring ink containing another coloring agent different from the aforementioned coloring agent.

[0157] (Operation example)

[0158] A flowchart using the first embodiment ( Fig.15 A description of the situation presented in the process). Fig.15 In S1506 of the present invention, the CPU 401 determines that there is no image without any image defect. The CPU 401 proceeds from the processing in S1506 to the processing in S1509. In S1509, the CPU 401 sets the second drying condition as the drying condition. Specifically, the CPU 401 sets "air blowing setting: on", "temperature setting: 30°C", and "air flow speed setting: 3m / s" as the drying condition. In S1510, the CPU 401 prints a test pattern under the second drying condition. Specifically, the CPU 401 causes the print head 105 to print the test pattern, while causing the platen blower unit 202 to supply heated air.

[0159] (with air blowing (second drying condition); easy to wet (high wettability))

[0160] Fig. 22 is a diagram illustrating the printing result of a test pattern on a printing medium having an easy-wetting property under a second drying condition. Specifically, Fig. 22 Presented in Fig.10 Under the second drying condition Figure 8B Printing on the print media with easy wetting properties shown in Fig.11 and Fig.19 The results of the test pattern in . Fig. 22 Images (a) to (e) in the figure show the Fig.14 The same results as in (a) to (e). Fig. 22 Images (f) to (j) in FIG. 1 show the newly added Fig.19 The results of the test pattern in . Fig. 22 Images (d) and (e) are images without ink diffusion. Fig. 22 Images (h) to (j) in FIG. 1 are images in which no bleeding occurs between inks of different colors. That is, Fig. 22 The images (h) to (j) in FIG. 1 are images in which there is no bleeding between a coloring ink containing a coloring agent and another coloring ink containing another coloring agent different from the aforementioned coloring agent.

[0161] (Operation example)

[0162] A flowchart using the first embodiment ( Fig.15 A description of the situation presented in the process). Fig.15In S1513 of the embodiment, the CPU 401 sets the second drying condition as the drying condition. Specifically, the CPU 401 sets "air blowing setting: on", "temperature setting: 30°C", and "air flow speed setting: 3m / s" as the drying condition. The setting may be made automatically. Alternatively, the setting may be made manually from a user interface provided in the printing device body or the host device 404. Next, the CPU 401 will Fig. 22 Test patterns (d) and (e) in Fig. 22 The reaction liquid volume (d) of the smallest liquid volume among the reaction liquid volumes in the two types of images without any image defects in the test patterns (h) to (j) is set as the ejection reaction liquid volume. The CPU 401 sets information on the ejection reaction liquid volume based on information included in the user input from the user interface provided in the printing device body or the host device 404.

[0163] (Operation example)

[0164] A flowchart using the second embodiment ( Fig.18 A description of the situation presented in the process). Fig.21 As presented in , in the case where air blowing under the first drying condition is performed on a printing medium having an easily wettable property, there does not exist an image without any image defects for the test pattern under the first drying condition. Therefore, in S1809, the user inputs information that there does not exist an image without any image defects. Thus, in S1810, the CPU 401 determines that there does not exist an image without any image defects. The CPU 401 proceeds from the processing in S1810 to the processing in S1813. In S1813, the CPU 401 sets the second drying condition as the drying condition. Specifically, the CPU 401 sets "air blowing setting: on", "temperature setting: 30°C", and "air flow speed setting: 3m / s" as the drying conditions. In S1814, the CPU 401 selects Fig. 22 (d) and (e) in Fig. 22 (h) to (j) in FIG. 4 are images without any image defects. Next, the CPU 401 uses Fig. 22 Test patterns (d) and (e) in Fig. 22 The reaction liquid volumes (d) and (i) of the smallest liquid volumes among the reaction liquid volumes in the two types of images without any image defects in the test patterns (h) to (j) in the image are set as the ejection reaction liquid volumes. The CPU 401 sets information on the ejection reaction liquid volumes based on information included in user input from a user interface provided in the printing device body or the host device 404.

[0165] In this way, it is possible to determine the drying conditions and the optimum reaction liquid volume while taking into account not only the ink diffusion phenomenon but also the bleeding phenomenon that may occur between different coloring inks.

[0166] For a print medium with an easy-to-wet property, if the dryer unit is operated during printing to blow heated air toward the surface of the print medium as described above, the following effects can be produced. Specifically, this operation can make it possible to promote the evaporation of water contained in the ink and promote the fixing of the ink. Moreover, it can be possible to prevent image defects caused by ink diffusion phenomena, and additionally prevent oozing phenomena that may occur between different coloring inks. In addition, since the minimum liquid volume is determined as the reaction liquid volume for preventing image defects, it can be possible to reduce the wasteful consumption of the reaction liquid volume. On the other hand, for a print medium with a difficult-to-wet property, if the dryer unit is prevented from blowing heated air toward the surface of the print medium during printing, the following effects can be produced. Specifically, this operation can make it possible to prevent image defects caused by the generation of streaky unevenness that may occur due to accelerated drying, and additionally prevent image defects caused by oozing phenomena that may occur between different coloring inks.

[0167] <<Other embodiments>>

[0168] (Test Pattern)

[0169] In the aforementioned embodiments, the test pattern used in the first to third embodiments of the present disclosure is described as the black letter "A", but the test pattern is not limited to the letter "A" and may be another letter or an image composed of a combination of elements other than letters. Fig.23 It is a diagram for explaining other test patterns. Fig.23 The image in (a) shows the Fig.11 The same letter "A" in Fig.23 The image (f) in Fig.19 The same letter "A" in (f) can be replaced by images (b) to (e) composed of combinations of free elements. Fig.23 (a) in the figure. Images (g) to (j) composed of combinations of free elements can be used instead. Fig.23 Alternatively, the coloring ink is not limited to black ink, and may be another coloring ink or a combination of two or more other coloring inks. Fig.19The background color of the different colored inks in the image printed adjacent to each other is yellow, but is not limited to this. For example, the background color can be another colored ink or a combination of two or more other colored inks. Alternatively, the background color can be a light colored ink with a large brightness difference from the image composed of a combination of elements. In addition, the ink volume of the colored ink used for the test pattern is described as a predetermined ink volume per unit area of ​​36 [pl / 600dpi], but is not limited to this ink volume and can be an ink volume corresponding to the ink volume specified by the user. Moreover, the reaction liquid volume per unit area is not limited to five levels at intervals of 5 [pl / 600dpi]: 0 [pl / 600dpi], 5 [pl / 600dpi], 10 [pl / 600dpi], 15 [pl / 600dpi] and 20 [pl / 600dpi]. The level of the reaction liquid volume per unit can also be set at smaller intervals. For example, the interval can be 0.5 [pl / 600dpi]. The number of levels can also be increased to 10. In addition, the image of the reaction liquid accompanied by the image of the color ink can be an image extending several pixels at 600dpi from the boundary of the area where the color ink is to be printed to the area where the color ink is not printed. The test patterns described in the first to third embodiments of the present disclosure are as follows. Specifically, in the first embodiment, the situation where the ink diffusion phenomenon occurs beyond the boundary between the area printed with the color ink and the area where the color ink is not printed is described. In the second embodiment, the situation where the seepage phenomenon occurs at the boundary between adjacent different color inks is described. In addition, a description of the situation where the optimal reaction liquid volume is determined to prevent the ink diffusion phenomenon beyond the boundary and the ink diffusion phenomenon at the boundary between adjacent different color inks is also given. However, the test pattern is not limited to these. Moreover, the test pattern can include multiple images to which different reaction liquid volumes are to be applied, which makes it possible to determine whether there are image defects that occur according to the reaction liquid volume, such as an image for determining the optimal reaction liquid volume for achieving uniformity (also referred to as granularity). Alternatively, in order to cope with all these types of image defect phenomena, the reaction liquid volume without any image defects can be selected, and then the minimum reaction liquid volume is determined in the above-selected liquid volume.

[0170] In the drying conditions for the platen blower unit 202 during printing described in the first to third embodiments, the second drying condition is set to air blowing with an air temperature of 30° C. and an air flow speed of 3 m / sec, but is not limited thereto. The drying conditions may include a plurality of sets of drying conditions with different air temperatures and air flow speeds. Fig.18 After S1808 in the described flowchart, the test pattern may be printed multiple times under different sets of drying conditions other than the first drying condition and the second drying condition, and the optimum drying condition may be determined among the drying conditions with air blowing.

[0171] In the aforementioned embodiment, an example in which the dryer unit includes the fan 202A and the heater 202B is described, but the dryer unit is not limited thereto. The dryer unit may include a heat exchanger. Alternatively, the dryer unit may include a dehumidifier.

[0172] Other embodiments

[0173] The (one or more) embodiments of the present invention may also be implemented by a computer of a system or device that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be more completely referred to as a "non-transitory computer-readable storage medium") to perform the functions of one or more of the above (one or more) embodiments and / or includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing the functions of one or more of the above (one or more) embodiments, and by a method executed by a computer of a system or device, for example, by reading out and executing computer executable instructions from a storage medium to perform the functions of one or more of the above (one or more) embodiments and / or controlling one or more circuits to perform the functions of one or more of the above (one or more) embodiments. The computer may include one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include a network of separate computers or separate processors to read out and execute computer executable instructions. Computer executable instructions may be provided to the computer, for example, from a network or a storage medium. The storage medium may include, for example, a hard disk, a random access memory (RAM), a read-only memory (ROM), a storage device of a distributed computing system, an optical disk (such as a compact disk (CD), a digital versatile disk (DVD), or a Blu-ray disk (BD)) TM ), flash memory devices, memory cards, etc.

[0174] Other embodiments

[0175] The embodiments of the present invention may also be implemented by providing software (program) for performing the functions of the above-described embodiments to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0176] While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. An inkjet printing device, comprising: a print head configured to print an image by ejecting a coloring ink and a reaction liquid onto a printing medium, the coloring ink containing a colorant, the reaction liquid contacting the colorant and causing the colorant to coagulate; a printer unit configured to cause a print head to print a plurality of test patterns on a print medium by correspondingly printing first pattern images with predetermined volumes of colored ink and correspondingly printing second pattern images with respectively different volumes of reactive liquid, the plurality of test patterns consisting of a plurality of first image patterns and a plurality of accompanying second pattern images; a dryer unit configured to dry the plurality of test patterns on the printing medium during printing of the plurality of test patterns on the printing medium under the control of the printer unit; an obtaining unit configured to obtain printing information corresponding to the printing results of each of the plurality of test patterns; as well as A determination unit configured to determine a volume of the reaction liquid used for printing on the printing medium and a drying condition of the dryer unit based on the printing information obtained by the obtaining unit.

2. The inkjet printing device according to claim 1, wherein In a case where the determination unit determines, based on the printing information, that there are one or more first pattern images in each test pattern in which the colored ink does not diffuse from the area printed with the colored ink beyond the boundary between the area printed with the colored ink and the area not printed with the colored ink, the determination unit determines the minimum volume among the volumes of the reaction liquid of the second pattern image accompanying the first pattern image determined above as the ejection liquid volume of the reaction liquid to be ejected by the print head.

3. The inkjet printing device according to claim 2, wherein The dryer unit includes a blower capable of controlling the air flow rate of air to be supplied to the print medium, The drying conditions include a first drying condition and a second drying condition, The first drying condition includes a controlled blowing setting that results in preventing the blower from supplying air, The second drying condition includes a blowing setting that causes the blower to supply air, When the determination unit determines that there are one or more first pattern images in which the colored ink does not spread beyond the boundary among the first pattern images based on the printing information, the determination unit causes the plurality of test patterns to be printed while being dried by the dryer unit under the first drying condition, and In a case where the determination unit determines that there is no first pattern image in which the colored ink does not spread beyond the boundary among the first pattern images, the determination unit causes the plurality of test patterns to be printed while being dried by the dryer unit under the second drying condition.

4. The inkjet printing device according to claim 3, wherein The dryer unit further includes a temperature adjuster capable of adjusting a temperature of air to be supplied to the printing medium.

5. The inkjet printing device according to claim 4, wherein The first drying condition also includes a temperature setting that prevents the temperature adjuster from adjusting the temperature of the air, and The second drying condition further includes a temperature setting for causing the temperature adjuster to adjust the temperature of the air.

6. The inkjet printing device according to claim 5, wherein In a state in which the dryer unit controls the blower and the temperature adjuster under the first drying condition, when the determination unit determines based on the printing information that there are one or more first pattern images in which the colored ink is not diffused among the first pattern images of each test pattern printed under the first drying condition, the determination unit determines the minimum volume among the volumes of the reaction liquid of the second pattern image accompanying the first pattern image determined above as the ejection liquid volume.

7. The inkjet printing device according to claim 5 or 6, wherein When the determination unit determines, based on the printing information, that there are one or more first pattern images in which the colored ink is not diffused among the first pattern images of each test pattern dried by the dryer unit under the second drying condition, the determination unit determines the minimum volume among the volumes of the reaction liquid of the second pattern image accompanying the first pattern image determined above as the ejection liquid volume.

8. The inkjet printing device according to any one of claims 3 to 6, wherein The determination unit determines whether spreading of the colored ink occurs in each of the first pattern images of the respective test patterns dried by the dryer unit under the first drying condition based on the print information.

9. The inkjet printing device according to any one of claims 3 to 6, wherein After the multiple test patterns are printed as multiple first test patterns when they are dried by the dryer unit under a first drying condition and a plurality of different test patterns other than the multiple test patterns are printed as multiple second test patterns when they are dried by the dryer unit under a second drying condition, the determination unit determines whether diffusion of the colored ink occurs in each of the first pattern images of the respective first test patterns based on the printing information.

10. The inkjet printing device according to any one of claims 2 to 6, wherein In a case where the determination unit determines based on the print information that one or more of the first pattern images do not have diffusion of the colored ink beyond the boundary of the region printed with the colored ink and one or more of the third pattern images do not have bleeding between the colored ink and the different colored ink at a boundary between the region printed with the colored ink and the region printed with a different colored ink other than the aforementioned colored ink, The determination unit determines the minimum volume of the reaction liquid for the second pattern image accompanying the first pattern image without diffusion of the colored ink and the volume of the reaction liquid for the second pattern image accompanying the third pattern image without bleeding between the colored ink and the different colored ink as the volume of the ejection liquid to be ejected by the print head.

11. The inkjet printing device according to any one of claims 2 to 6, further comprising an input unit configured to receive an input from a user, wherein The obtaining unit obtains input information based on the user's input received by the input unit as print information.

12. The inkjet printing device according to any one of claims 2 to 6, further comprising an image capturing unit configured to capture images of the plurality of test patterns printed on a printing medium, wherein The obtaining unit obtains captured image information based on images of the plurality of test patterns captured by the image capturing unit as print information.

13. The inkjet printing device according to claim 12, wherein When the obtaining unit obtains captured image information as printing information, the determining unit determines whether diffusion of the colored ink occurs based on similarity of each of the plurality of test patterns as a printing result corresponding to the printing information and an ideal test pattern without diffusion of the colored ink.

14. The inkjet printing device according to claim 12, wherein In a case where the obtaining unit obtains captured image information as the printing information, the determining unit determines whether the spreading of the colored ink occurs based on a machine learning model trained to distinguish whether the spreading of the colored ink occurs. 15 . The inkjet printing device according to claim 1 , further comprising a display unit configured to display information on the images of the plurality of test patterns.

16. An inkjet printing method, comprising: A first printing step of printing an image by ejecting a coloring ink containing a colorant and a reaction liquid onto a printing medium, the coloring ink containing a colorant, the reaction liquid contacting the colorant and causing the colorant to coagulate; a second printing step of printing a plurality of test patterns on the print medium in the first printing step by correspondingly printing the first pattern images with a predetermined volume of the colored ink and correspondingly printing the second pattern images with a different volume of the reactive liquid, the plurality of test patterns consisting of a plurality of first image patterns and a plurality of accompanying second pattern images; a drying step of drying the plurality of test patterns on the printing medium during printing of the plurality of test patterns on the printing medium in the second printing step; An obtaining step of obtaining printing information corresponding to the printing results of each of the plurality of test patterns; as well as A determining step of determining a volume of the reaction liquid used for printing on the printing medium and a drying condition in the drying step based on the printing information obtained in the obtaining step.

17. An inkjet printing system comprising an inkjet printing device configured to print an image on a print medium; as well as An input unit is configured to receive a user's input, wherein The inkjet printing device comprises: a print head configured to print an image by ejecting a coloring ink and a reaction liquid onto a printing medium, the coloring ink containing a colorant, the reaction liquid contacting the colorant and causing the colorant to coagulate; a printer unit configured to cause a print head to print a plurality of test patterns on a print medium by correspondingly printing first pattern images with predetermined volumes of colored ink and correspondingly printing second pattern images with respectively different volumes of reactive liquid, the plurality of test patterns consisting of a plurality of first image patterns and a plurality of accompanying second pattern images; a dryer unit configured to dry the plurality of test patterns on the printing medium during printing of the plurality of test patterns on the printing medium under the control of the printer unit; an obtaining unit configured to obtain printing information corresponding to printing results of each of the plurality of test patterns; and a determining unit configured to determine a volume of a reaction liquid used for printing on a printing medium and a drying condition of a dryer unit based on the printing information obtained by the obtaining unit, and The obtaining unit obtains input information based on the user's input received by the input unit as print information.

18. An inkjet printing system comprising an inkjet printing device configured to print an image on a print medium; as well as An image capture unit configured to capture an image, wherein The inkjet printing device comprises: a print head configured to print an image by ejecting a coloring ink and a reaction liquid onto a printing medium, the coloring ink containing a colorant, the reaction liquid contacting the colorant and causing the colorant to coagulate; a printer unit configured to cause a print head to print a plurality of test patterns on a print medium by correspondingly printing first pattern images with predetermined volumes of colored ink and correspondingly printing second pattern images with respectively different volumes of reactive liquid, the plurality of test patterns consisting of a plurality of first image patterns and a plurality of accompanying second pattern images; a dryer unit configured to dry the plurality of test patterns on the printing medium during printing of the plurality of test patterns on the printing medium under the control of the printer unit; an obtaining unit configured to obtain printing information corresponding to printing results of each of the plurality of test patterns; and a determining unit configured to determine a volume of a reaction liquid used for printing on a printing medium and a drying condition of a dryer unit based on the printing information obtained by the obtaining unit, and The obtaining unit obtains captured image information based on images of the plurality of test patterns captured by the image capturing unit as print information.

Images