Recording device, control method of the same, and program

Abstract

To perform various kinds of adjustments automatically in a recording device using a white ink.SOLUTION: One embodiment of the invention includes: transporting means which transports a recording medium; recording means having a recording head including first nozzles configured to discharge a first liquid containing a white coloring material and second nozzles configured to discharge a second liquid, the recording means configured to record an image including an adjustment pattern; reading means which reads the image recorded on the recording medium; fixing means which fixes the image recorded by the recording means to the recording medium; and adjusting means which performs adjustment based on a reading result of the adjustment pattern by the reading means. After a first image, which serves as a foundation and is recorded with the first liquid by the recording means, is fixed by the fixing means, the adjustment pattern is recorded on the first image with the second liquid by the recording means.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] The present disclosure relates to a recording device that records an image by ejecting ink from nozzles of a recording head. [Background technology]

[0002] Inkjet recording devices are known that record images by ejecting ink onto a non-absorbent or low-absorbent recording medium and drying the ink applied to the recording medium using a fixing device having a heating or air blowing function. In such devices, images may be recorded on transparent or colored recording media that have a lower reflectance than white recording media. In addition, in order to record high-quality images, it is necessary to adjust the recording head and the recording device using the recording medium on which the image is actually recorded.

[0003] Patent Document 1 discloses a technique for recording a white ink base and then recording a color chart in order to eliminate the influence of the color of the mount when recording and measuring an adjustment pattern using a recording medium having a mount and a sheet attached to the mount. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-133601 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 does not take into consideration a fixing process in which the ink is dried using a fixing device having a heating or air blowing function. If a base is recorded with a first ink on a non-absorbent or low-absorbent recording medium, and then an adjustment pattern is recorded with a second ink without going through a fixing process, there is a risk that the first ink and the second ink will mix because the base is not sufficiently dried. This causes problems such as deviation in the recording position of the second ink and failure to obtain the desired dot shape.

[0006] In view of the above-mentioned problems, an object of the present disclosure is to make it possible to automatically perform various adjustments in a printing apparatus capable of printing using white ink. [Means for solving the problem]

[0007] One embodiment of the present invention is a recording device having a transport means for transporting a recording medium, and a recording means for recording an image having a recording head, the recording head having a first nozzle for ejecting a first liquid containing a white colorant and a second nozzle for ejecting a second liquid, the image including an adjustment pattern, the recording means, a reading means for reading the image recorded on the recording medium, a fixing means for fixing the image recorded by the recording means to the recording medium, and an adjustment means for performing adjustment based on the reading result of the adjustment pattern by the reading means, and after a first image as a base recorded by the recording means using the first liquid or the second liquid is fixed by the fixing means, the recording means records the adjustment pattern on the first image using the liquid of the first liquid or the second liquid that was not used in recording the first image. Effect of the Invention

[0008] According to the present disclosure, it is possible to automatically perform various adjustments in a printing apparatus capable of printing using white ink. [Brief description of the drawings]

[0009] [Figure 1]A perspective view of a recording device [Diagram 2] Schematic side view of a recording device [Diagram 3] Schematic diagram of a recording head [Figure 4] Schematic diagram of an optical sensor [Diagram 5] A block diagram showing the configuration of a control system of a printing apparatus. [Figure 6] FIG. 1 is a diagram for explaining multi-pass printing. [Figure 7] FIG. 1 is a diagram for explaining a registration adjustment pattern; [Figure 8] Flowchart for performing registration adjustment processing (or transport adjustment processing) [Figure 9] FIG. 13 is a diagram for explaining a transport adjustment pattern; [Figure 10] Flowchart for performing color calibration [Figure 11] FIG. 1 is a diagram for explaining a color calibration adjustment pattern. [Figure 12] Schematic diagram of fixing the base image [Figure 13] Schematic diagram when the base image is not fixed [Figure 14] Flowchart for making various adjustments [Figure 15] Detailed flow chart of S1403 [Figure 16] Flowchart of a process for recording an arbitrary image on a base image [Figure 17] W Nozzle Color Calibration Flowchart DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] [First embodiment] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings.

[0011] <Configuration of Inkjet Printing Apparatus> Fig. 1 is a perspective view showing the exterior of an inkjet recording apparatus A (hereinafter also referred to as a recording apparatus or printer) according to this embodiment. The recording apparatus A is a so-called serial scan type printer, which records an image by scanning a recording head in an X direction (main scanning direction) that intersects (specifically, is perpendicular to) the Y direction (sub-scanning direction) of a recording medium P. Below, an outline of the configuration of the recording apparatus A and its operation during recording will be described with reference to Fig. 1.

[0012] First, the recording medium P is conveyed in the Y direction toward the take-up spool 12 that holds the recording medium P by a conveying roller driven via a gear by a conveying motor (not shown). On the other hand, when the recording medium P is at a predetermined conveying position, a carriage 22 is caused to perform reciprocating scanning (reciprocating movement) along a guide shaft 8 extending in the X direction by a carriage motor (not shown). Then, during this scanning process, ink is discharged from the nozzles of a recording head (described later) that can be mounted on the carriage 22 at a timing based on a position signal obtained by an encoder 7, and an image of a certain bandwidth corresponding to the nozzle arrangement range is recorded. After that, the recording medium P is conveyed, and an image of the next bandwidth is recorded. In this embodiment, the scanning speed is 40 inches per second, and the discharge operation is performed at a recording resolution of 1200 dpi (1 / 1200 inch interval). However, it is also possible to scan at a speed of 40 inches per second or faster.

[0013] A carriage belt can be used to transmit the driving force from the carriage motor to the carriage 22. Note that instead of the carriage belt, other transmission means can be used, such as one including a lead screw that is rotationally driven by the carriage motor and extends in the X direction, and an engagement portion that is provided on the carriage 22 and engages with a groove in the lead screw.

[0014] The fed recording medium P is sandwiched between a feed roller and a pinch roller and guided to a recording position on the platen 4 (a position within the range of the area that the recording head can scan, where recording is performed by the recording head). Hereinafter, the configuration that records an image around the recording position will be referred to as the "image recording unit (image recording means)." When the recording device is in a resting state, the face of the recording head is usually capped, so the cap is opened prior to recording to make the recording head ready for recording or scanning. After that, when data for one scan has been accumulated in the buffer, the carriage 22 is scanned by the carriage motor, and recording is performed as described above.

[0015] FIG. 2 is a schematic side view of the main body of the recording device A. A curing area (hereinafter, the configuration for fixing the image around the curing area is referred to as an "image fixing section (image fixing means)") is provided downstream in the sub-scanning direction Y from the position where the recording head 9 mounted on the carriage 22 reciprocates in the X direction (main scanning direction). In the image fixing section, a heater 10 supported by a frame (not shown) is arranged and dries the liquid ink on the recording medium P by heat. The heater 10 is covered by a heater cover 11, which has the function of efficiently irradiating the heat of the heater 10 onto the recording medium P and the function of protecting the heater 10. After recording is performed by the recording head 9, the recording medium P is wound up by a take-up spool 12 to form a roll-shaped wound medium. Specific examples of the heater 10 include a sheath heater and a halogen heater. The heating temperature of the heating section in the image fixing section described above is set in consideration of the film-forming properties and productivity of the water-soluble resin fine particles and the heat resistance of the recording medium P. The heating method of the heating unit in the image fixing unit may be heating by blowing hot air from above, heating by a contact-type heat conduction heater from below the recording medium, etc. In addition, although the heating unit is installed at one location in this embodiment, two or more locations may be installed and used together as long as the temperature measured on the recording medium P using a radiation thermometer (not shown) does not exceed the set value of the heating temperature.

[0016] The recording apparatus A of this embodiment can perform so-called multi-pass recording, in which an image is recorded in a predetermined area (1 / n band) on the recording medium P by scanning the recording head multiple times (n times). This multi-pass recording will be described in detail later.

[0017] <Recording head configuration> 3 shows a nozzle surface 34 of a print head 9 in this embodiment. The print head 9 has a nozzle row 33K that ejects black ink, a nozzle row 33C that ejects cyan ink, a nozzle row 33M that ejects magenta ink, a nozzle row 33Y that ejects yellow ink, and a nozzle row 33W that ejects white ink. In this specification, when there is no particular need to distinguish between them by color, they will be collectively referred to as nozzle rows 33. This rule of generalization also applies to components other than the nozzle rows.

[0018] In the recording head 9, the nozzle rows are arranged in the order of nozzle row 33K, nozzle row 33C, nozzle row 33M, nozzle row 33Y, and nozzle row 33W in the +X direction. Each of these nozzle rows is configured by 1280 nozzles 30 that eject the corresponding ink, arranged in the Y direction (arrangement direction) at a density of 1200 dpi. In this embodiment, the amount of ink ejected from one nozzle 30 at one time is about 4.5 pl.

[0019] These nozzle rows are connected to ink tanks (not shown) that store the corresponding inks, respectively, and the inks are supplied to the nozzle rows. Note that the print head 9 and the ink tanks in this embodiment may be configured as an integrated unit or may be configured separately.

[0020] The recording head 9 is provided with energy generating elements (hereinafter also referred to as recording elements) that generate ejection energy for ejecting ink from the nozzles. As the energy generating elements, electrothermal transducers are used that locally heat the ink to cause film boiling, and eject the ink by the resulting pressure. However, the technology disclosed herein is not limited to electrothermal transducers, and can also be applied to the case where electromechanical transducers are used.

[0021] <Optical sensor> Fig. 4(a) is a schematic diagram showing a schematic configuration of the optical sensor, and Fig. 4(b) is a diagram showing a detection spot. The optical sensor 200 is fixedly provided on the carriage 22 so that a measurement area in the Y direction is located downstream in the +Y direction from the multiple nozzle rows provided in the recording head 9. A lower surface 200a of the optical sensor 200 coincides with the nozzle surface 34 in the Z direction, or is located downstream of the nozzle surface 34 in the +Z direction.

[0022] The optical sensor 200 has a light emitting unit 202 realized by a visible LED such as red, green, or blue, and a light receiving unit 204 realized by a photodiode. The light emitting unit 202 and the light receiving unit 204 are provided on a lower surface 200a of the optical sensor 200, the light emitting unit 202 irradiates light onto the recording medium P, and the light receiving unit 204 receives the reflected light reflected by the recording medium P. Therefore, in the optical sensor 200, the light 206 irradiated from the light emitting unit 202 is diffusely reflected by the recording medium P, and this reflected light 208 is received by the light receiving unit 204. The diameter of the detection spot 210 where the light 206 irradiated from the light emitting unit 202 is diffusely reflected by the recording medium P is, for example, approximately 3 mm.

[0023] In the light receiving unit 204, a detection signal (analog signal) of the received reflected light 208 is transmitted to a control circuit on an electric board of the recording device A via a flexible cable (not shown) or the like, and is converted into a digital signal by an A / D converter in the control circuit. When detecting the optical characteristics of the adjustment pattern, which will be described later, the conveyance of the recording medium P along the Y direction and the movement of the carriage 22, to which the optical sensor 200 is attached, in the X direction are alternately performed. As a result, the optical sensor 200 detects the density of the image recorded on the recording medium P as optical reflectance, in synchronization with the timing based on the position signal obtained by the encoder 7.

[0024] <Control system configuration> The following describes the configuration of the control system of the recording apparatus A. Figure 5 is a block diagram showing the configuration of the control system of the recording apparatus.

[0025] The control unit 100, which controls the entire recording apparatus, has a CPU 102, a ROM 104, a RAM 106, and a memory 108. The CPU 102 controls the operation of each component of the recording apparatus and processes input image data based on various programs. The ROM 104 functions as a memory that stores programs related to various controls executed by the CPU 102 and programs related to image data processing. The RAM 106 temporarily stores various data used to control the recording apparatus. The memory 108 stores various data such as mask patterns and adjustment patterns, which will be described later. The control unit 100 also has an input / output port 110, and is connected to various drivers and drive circuits via the input / output port 110.

[0026] The control unit 100 is connected to an interface circuit 112 via an input / output port 110, and is connected to a host device 114 via the interface circuit 112. The control unit 100 is also connected to an operation panel 124 that can be operated by a user via the input / output port 110. A user inputs image data to the recording device via the host device 114, and inputs various information to the recording device via the host device 114 and the operation panel 124. The control unit 100 is also connected to a motor driver 116 via the input / output port 110, and controls the driving of a motor 118 via the motor driver 116. In FIG. 5, various motors in the recording device, such as a motor that moves the carriage 22 and a motor that drives a conveying unit that conveys the recording medium P, are collectively shown as a motor 118.

[0027] The control unit 100 is connected to the head driver 120 via the input / output port 110, and controls the recording head 9 via the head driver 120 to eject ink. The control unit 100 is also connected to a drive circuit 122 via the input / output port 110, and controls the drive of the heater 10 via the drive circuit 122. The control unit 100 is also connected to an optical sensor 200 via the input / output port 110, and controls the drive of the optical sensor 200, and detects the optical characteristics of the adjustment pattern based on the output from the optical sensor 200. In this way, in this embodiment, the control unit 100 and the optical sensor 200 function as a detection unit capable of detecting the optical characteristics of an image recorded on a recording medium.

[0028] In the control unit 100, the CPU 102 converts image data input from the host device 114 into print data and stores it in the RAM 106. Specifically, when the CPU 102 acquires image data in a bitmap format represented by 8-bit, 256-value information (0 to 255) for each of RGB, it converts this image data into multi-value data represented by K, C, M, Y, and W used for printing. This color conversion process generates multi-value data represented by 8-bit, 256-value information (0 to 255) that defines the gradation of each of the K, C, M, Y, and W inks in each pixel group made up of a plurality of pixels.

[0029] Next, quantization of multi-value data represented by K, C, M, Y, and W is performed to generate quantized data (binary data) represented by 1-bit binary information (0, 1) that determines whether or not each of the inks K, C, M, Y, and W is ejected for each pixel. As the quantization process, various known quantization methods such as error diffusion, dithering, and indexing can be used. After that, a distribution process is performed to distribute the quantized data to a plurality of scans of the recording head 9 for the unit area. This distribution process generates recording data represented by 1-bit binary information (0, 1) that determines whether or not each of the inks K, C, M, Y, and W is ejected for each pixel in each of the plurality of scans of the unit area of ​​the recording medium P. This distribution process corresponds to the plurality of scans and is performed using a mask pattern that determines whether or not ink ejection is permitted for each pixel. Note that the generation of such recording data is not limited to being performed by the control unit 100, and may be performed by the host device 114, or a part of the process may be performed by the host device 114 and the remaining process may be performed by the control unit 100.

[0030] <Multi-pass printing method> In this embodiment, an image is printed by so-called multi-pass printing, in which printing is performed on a predetermined area on a print medium by multiple scans using each of the K, C, M, Y, and W inks.

[0031] First, multi-pass printing using the entire area of ​​the nozzle array will be described using W ink and K ink as an example.

[0032] FIG. 6(a) is a diagram for explaining a multi-pass printing method using the entire nozzle array region of the W ink and K ink. Here, W ink and K ink are ejected in each of six scans on a predetermined region from each of six nozzle groups A1 to A6 formed by dividing the nozzle array 33W and the nozzle array 33K in the Y direction. The print data of the W ink and the K ink are distributed to each scan so that the printing of an image is completed in six scans. Note that, in reality, the print medium P is transported downstream in the Y direction between scans of the print head 9, but for simplicity, FIG. 6 shows the print head 9 moving upstream in the Y direction between scans.

[0033] First, in the first scan (first scan), W ink and K ink are ejected from the nozzle group A1 in the nozzle row 33W and the nozzle row 33K to the predetermined region 80 according to the respective print data for W ink and K ink corresponding to the first scan. After the first scan is completed, the print medium is transported in the Y direction by a distance corresponding to one nozzle group. Then, the second scan (second scan) is performed, and W ink and K ink are ejected from the nozzle group A2 to the predetermined region 80. After that, the print medium is transported and ink is ejected from the print head alternately, and ink is ejected from the nozzle groups A3 to A6 in the third to sixth scans to the predetermined region 80. In this manner, multi-pass printing to the predetermined region 80 is completed.

[0034] Next, a multi-pass printing method in which the nozzle array region used varies depending on the ink color will be described. Fig. 6(b) is a diagram illustrating the nozzle regions corresponding to the nozzle groups A1 to A3 and the nozzle regions corresponding to the nozzle groups A4 to A6 among all the nozzles in the nozzle arrays 33K and 33W. In the nozzle array 33K, there are a nozzle region 44K corresponding to the nozzle groups A1 to A3 and a nozzle region 55K corresponding to the nozzle groups A4 to A6. In addition, in the nozzle array 33W, there are a nozzle region 44W corresponding to the nozzle groups A1 to A3 and a nozzle region 55W corresponding to the nozzle groups A4 to A6.

[0035] Fig. 6(c) is a diagram showing that, of the nozzle groups A1 to A6 shown in Fig. 6(a), W ink is ejected from nozzle group A1 to A3 which corresponds to nozzle region 44W, and K ink is ejected from nozzle group A4 to A6 which corresponds to nozzle region 55K. Here, the print data for W ink is distributed so that image printing is completed in the first to third scans, and the print data for K ink is distributed so that image printing is completed in the fourth to sixth scans.

[0036] First, in the first scan (first scan), W ink is ejected from the nozzle group A1 in the nozzle row 33W to the predetermined region 80 according to the W ink print data corresponding to the first scan. After the first scan is completed, the print medium is transported in the Y direction by a distance corresponding to one nozzle group. Thereafter, ink ejection from the print head and transport of the print medium are alternately performed, and second and third scans (second and third scans) are performed, W ink is ejected from the nozzle groups A2 to A3 in the nozzle row 33W to the predetermined region 80, and the W ink image is completed by the third scan. Next, K ink is ejected from the nozzle group A4 in the nozzle row 33K to the predetermined region 80 according to the K ink print data corresponding to the fourth scan. Thereafter, transport of the print medium and ink ejection from the print head are alternately performed, and K ink is ejected from the nozzle groups A4 to A6 in the nozzle row 33K to the predetermined region 80 in the fourth to sixth scans. In this manner, multi-pass printing to the predetermined region 80 is completed.

[0037] By dividing the nozzle array groups used for W ink and K ink in this way, it is possible to record an image such that an image of W ink is completed in the first three scans out of six scans on the predetermined area 80, and an image of K ink is completed in the last three scans. In other words, it is possible to record an image of K ink over an image recorded in W ink on the predetermined area 80.

[0038] <Ink> The K ink, C ink, M ink, Y ink, and W ink used in this embodiment will be described below. These inks contain solid components that record images and liquid components that volatilize. The solid components include coloring materials such as pigments and dyes, and the liquid components include water and water-soluble organic solvents. Each ink contains water-soluble resin particles that bring the coloring materials into close contact with the recording medium and improve the abrasion resistance (fixability) of the recorded image.

[0039] <Recording Media> The recording device in this embodiment records on a low-permeability recording medium that is difficult for moisture to penetrate. As described above, the low-permeability recording medium refers to a medium that has no water absorption or absorbs only a very small amount of water. Therefore, with aqueous ink that does not contain organic solvents, the ink is repelled and images cannot be recorded. However, the low-permeability recording medium has excellent water resistance and weather resistance, and is suitable as a medium for recording records that are expected to be used outdoors. Usually, a recording medium with a contact angle of water of 45° or more, preferably 60° or more at 25°C is used.

[0040] Low-permeability recording media include recording media having a plastic layer formed on the outermost surface of a substrate, recording media having no ink-receiving layer formed on the substrate, and sheets, films, banners, etc. of glass, YUPO, plastic, etc. Examples of the above-mentioned coated plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc. These low-permeability recording media are generally used when recording materials for outdoor exhibition because they have excellent water resistance, light resistance, and abrasion resistance.

[0041] As an example of a method for evaluating the permeability of a recording medium, the Bristow method described in JAPAN TAPPI Paper and Pulp Test Method No. 51 "Test Method for Liquid Absorbency of Paper and Paperboard" can be used. The measurement method for the Bristow method is briefly explained below. First, a specified amount of ink is poured into a holding container with an opening slit of a specified size, and through the slit, it is brought into contact with a recording medium that has been processed into a strip and wrapped around a disk. Next, with the position of the holding container fixed, the disk is rotated and the area (length) of the ink band that is transferred to the recording medium is measured. From the area of ​​this ink band, the amount of ink transferred per unit area per second (ml m -2 In this embodiment, the 30 msec 1 / 2 The amount of ink transferred (absorption amount) at 10 ml m -2 Recording media smaller than this are considered low permeability recording media.

[0042] <Various adjustments> Various adjustments made in this embodiment will be described below.

[0043] (1) Registration adjustment First, the registration adjustment will be specifically described.

[0044] The recording head 9 in this embodiment moves in the main scanning direction, and has nozzles arranged to eject ink in a direction intersecting the main scanning direction (sub-scanning direction). In a recording device using such a recording head 9, a process is required to obtain appropriate ejection timing to align the landing positions of ink droplets ejected from each nozzle row (this process is called registration adjustment or regi adjustment).

[0045] In bidirectional printing, where printing is performed while the print head is scanned back and forth, registration adjustment is performed to match the landing positions of ink droplets in the forward and backward printing. Registration adjustment for bidirectional printing is achieved by correcting the ink ejection timing for backward printing with respect to that for forward printing.

[0046] As a registration adjustment method, for example, a reference pattern is printed with a certain reference nozzle row, and multiple patterns with slightly shifted printing positions are printed with other nozzle rows to obtain a registration adjustment correction amount (hereinafter referred to as a registration adjustment value) that matches the printing positions. In addition, in bidirectional printing, a reference pattern is printed in the forward direction, and multiple patterns with shifted printing positions are printed in the reverse direction to obtain a registration adjustment value that matches the printing positions in the forward and reverse directions.

[0047] Here, the configuration of the registration adjustment pattern used during the registration adjustment process will be described with reference to FIG.

[0048] FIG. 7A is a diagram for explaining a configuration example of a registration adjustment pattern when density is detected by the optical sensor of this embodiment.

[0049] The registration adjustment pattern is configured such that a rectangular pattern of i pixels by n pixels is periodically repeated in the main scanning direction for each blank area of ​​m pixels. The registration adjustment pattern includes a reference pattern 501 and a shift pattern 502, and the shift pattern 502 is printed with its printing position shifted by a predetermined number of pixels a with respect to the reference pattern 501. The resolution and shift amount of these registration adjustment patterns may be determined according to the printing resolution of the printing device. In this embodiment, the printing resolution is assumed to be 1200 dpi. Also, in FIG. 7(a), for convenience of explanation, the reference pattern and the shift pattern are illustrated shifted vertically, but in reality, these patterns are printed overlapping each other. In other words, the reference pattern is printed overlapping the shift pattern shifted by a predetermined number of pixels a in the main scanning direction.

[0050] FIG. 7(b) shows a configuration in which a plurality of registration adjustment patterns shown in FIG. 7(a) are arranged in the main scanning direction. In this case, the registration adjustment pattern group 610 shown in FIG. 7(b) is printed while changing the shift amount a of the shift pattern from -3 pixels to +3 pixels. That is, as can be seen from FIG. 7(b), when the shift amount is 0, the reference pattern and the shift pattern are printed overlapping each other. On the other hand, the larger the shift amount is, the larger the shift between the reference pattern and the shift pattern becomes, so that the width of the pattern becomes wider. For convenience, FIG. 7(b) shows an example in which the shift amount is 0 and the shift between the reference pattern and the shift pattern is small, but when the registration adjustment pattern is actually printed, the value of the shift amount at which the shift between the reference pattern and the shift pattern is small varies depending on various conditions.

[0051] When the amount of shift between the printing positions of the reference pattern and the shift pattern changes, the area ratio of the ink on the printing medium changes, as shown in FIG. 7(b).

[0052] Fig. 7(c) shows the measurement result 720 of the optical reflectance when each of the shift patterns shown in Fig. 7(b) is measured by the optical sensor 200. Note that the density is inversely proportional to the reflectance, and the smaller the position shift between the registration adjustment patterns actually recorded on the recording medium, the lower the density. In other words, the higher the reflectance of the shift pattern, the less the position shift occurs, and the shift amount when the density of the registration adjustment pattern is the lowest can be set as the registration adjustment value.

[0053] The number of registration adjustment patterns to be recorded on the recording medium and the amount of shifting may be determined according to the adjustment range required by the mechanical tolerance of the device and the unit of shifting the recording position. In other words, they may be determined according to the accuracy of the registration adjustment process. The recording area of ​​the registration adjustment patterns may be determined according to the size of the detection area of ​​the optical sensor 200, the width of the area that can be recorded in one recording scan, the size of the registration adjustment pattern group and the recordable area of ​​the recording medium, etc.

[0054] In addition, the nozzle row used to print the reference pattern and the shift pattern is determined by a combination of the ink color and the scanning direction of the nozzle row to be adjusted. For example, for the registration adjustment of the ink color of the nozzle row, a reference nozzle row (for example, nozzle row 33K) is determined to print the reference pattern, and the other nozzle row (for example, nozzle row 33C) prints the shift pattern. In addition, the registration adjustment during bidirectional printing can be performed in the same manner as above. For example, when printing the reference pattern, the nozzle row 33K is used to perform forward printing, and when printing the shift pattern, the nozzle row 33K is used to perform backward printing. This allows the registration adjustment of bidirectional printing using the same nozzle row 33K to be performed with high accuracy. The combination of nozzle rows is not limited to this, and any appropriate combination may be used.

[0055] The registration adjustment value is determined or set based on the position shift amount a determined in this manner. The registration adjustment value is a value indicating the amount of correction for the ink ejection timing, and the ink ejection timing of each nozzle row is controlled based on this registration adjustment value. Note that the position shift amount a may be used as is as the registration adjustment value, or a value derived based on the position shift amount a may be used as the registration adjustment value.

[0056] FIG. 8 is a flowchart showing the process of performing registration adjustment using a white recording medium in this embodiment.

[0057] First, in step S801, the CPU 102 uses the white portion of the recording medium to execute a light amount adjustment process for the optical sensor 200. Note that, hereinafter, for simplicity, "step S~" will be abbreviated to "S~".

[0058] In S802, the CPU 102 executes a recording process using the image recording unit to record the adjustment patterns shown in FIGS. 7A and 7B on a recording medium.

[0059] In S803, the CPU 102 executes a reading process using an optical sensor to read the adjustment pattern recorded in S802.

[0060] In S804, the CPU 102 calculates an adjustment value based on the detection result of the reading in S803.

[0061] In S805, the CPU 102 sets the registration adjustment value, that is, stores the adjustment value calculated in S804 in the RAM 106.

[0062] In S806, CPU 102 feeds the recording medium so as to prevent staining due to the ink used to record the adjustment pattern. As a result of the feeding in this step, the adjustment pattern recorded on the recording medium reaches the image fixing unit. Here, "feeding" refers to transporting the recording medium in the forward direction. The forward direction is the direction from the upstream side to the downstream side in the transport direction, i.e., the +Y direction (see FIG. 1, etc.). As a control for "the adjustment pattern recorded on the recording medium reaching the image fixing unit", for example, it is possible to pre-store the number of rotations of the motor corresponding to the distance between the optical sensor and the image fixing unit, and compare the stored number of rotations with the number of rotations during actual operation.

[0063] Finally, in S807, the CPU 102 uses the image fixing unit to execute a fixing process for fixing the ink used to record the adjustment pattern onto the recording medium, and then ends the registration adjustment process.

[0064] (2) Transportation Adjustment Next, the transport adjustment will be specifically described.

[0065] Transport adjustment refers to correcting the sub-scanning direction (the transport amount of the recording medium) so that the dot landing positions of the previous recording scan and the dot landing positions of the subsequent recording scan after the recording medium is transported align. One method of transport adjustment is to calculate the transport amount fluctuation amount from the difference between two adjustment patterns in order to measure the fluctuation in the transport amount that occurs when the recording medium is transported.

[0066] Fig. 9 is a diagram showing an example of printing a transport adjustment pattern using nozzle row 33K. As shown in Fig. 9, one adjustment pattern is made up of seven patches (indicated as 0 to 6 in the figure). Note that, although an example using seven patches is described here, the number of patches is not limited to seven, and may be set to any number so that an optimal transport amount can be set according to the ink and recording medium used.

[0067] One row of nozzles is divided into two in the sub-scanning direction. The downstream nozzles are called block 1, and the upstream nozzles are called block 2. First, as shown in Figure 9(a), a reference pattern is printed using specific nozzles located in block 2, which is on the upstream side in the sub-scanning direction. Seven reference patterns lined up in the carriage scanning direction are printed by the same specific nozzles in block 2.

[0068] Next, the command pulse value is set to 5120 and the recording medium is conveyed. As shown in Figure 9(b), the seven shift patterns printed using the nozzles of block 1 are printed using different combinations of nozzles, thereby printing patterns that are shifted relatively to the reference pattern. Here, the dots printed in white indicate dots printed using the upstream nozzles, and the dots printed in black indicate dots printed using the downstream nozzles. In this way, one patch is formed by printing the reference pattern and the shift patterns using different printing scans.

[0069] The transport resolution is a value that depends on the printer's performance, but here we will assume that the recording medium can be transported at a resolution of 9600 dpi. Under these conditions, the command pulse value (number of nozzles equivalent to half the nozzle row x resolution of the nozzle row / transport amount resolution) used to transport an amount equivalent to half the nozzles is as follows:

[0070] 640×25.4 / 1200 / 25.4×9600=5120...Formula (1) In addition, in formula (1), the number of nozzles is 640, which corresponds to half of the nozzle row, the resolution of the nozzle row (nozzle spacing) is 1200 dpi, and the resolution of the transport amount is 9600 dpi. Also, the theoretical transport amount of the recording medium transported by this command pulse value (5120) is as follows.

[0071] 640×25.4 / 1200=13.55[mm]···Equation (2) After the recording medium has been conveyed by the theoretical conveyance amount described above, a calibration pattern is printed using the downstream nozzles of the print head.

[0072] For convenience, Figure 9(b) shows an example in which the deviation between the reference pattern and the shift pattern is small in the case of patch 3. However, when a transport adjustment pattern is actually recorded, the patch identification number with the smallest deviation between the reference pattern and the shift pattern will differ depending on various conditions.

[0073] In the transport adjustment, the density decreases as the positional deviation between the reference pattern and the shift pattern printed on the printing medium decreases. Therefore, the transport distance of the printing medium when the patch with the lowest density is printed is the ideal transport distance. In other words, as with the registration adjustment described above in (1), the optimal paper transport distance can be derived by selecting the patch with the lowest density (the patch with the highest reflectance).

[0074] In this embodiment, the reference pattern is printed using the nozzles in block 2 on the upstream side, and the adjustment pattern is printed using the nozzles in block 1 on the downstream side, but it makes no difference whether the pattern is printed in block 1 or block 2.

[0075] Fig. 8 is a flowchart for performing the transport adjustment process using a white recording medium in this embodiment. The transport adjustment process can be performed using the same flowchart as the above-mentioned (1) registration adjustment. That is, in (1) registration adjustment, the adjustment pattern printed in S802 was the registration adjustment pattern shown in Fig. 7(a) and Fig. 7(b), but in (2) transport adjustment, the transport adjustment pattern shown in Fig. 9(a) and Fig. 9(b) is printed. The transport adjustment process and the registration adjustment process differ only in the adjustment pattern printed, so a description of the flowchart for the transport adjustment process will be omitted.

[0076] (3) Color calibration Next, color calibration will be specifically described.

[0077] In a recording device having multiple recording heads, or multiple nozzle rows such as the recording head 9 used in this embodiment, the desired color tone may not be obtained in the recorded image due to differences in the ejection characteristics of each recording head or each nozzle row. This is because differences in the ejection characteristics exist for each recording head or each nozzle row, or occur after the fact. This is because the density value of the recorded image changes due to differences in the ejection characteristics.

[0078] Color calibration is a technique for dealing with differences in color tone caused by differences in the ejection characteristics of each print head or each nozzle row.

[0079] Specifically, an adjustment pattern including a measurement color patch is recorded on a recording medium, and information about the color of an image to be recorded by a recording head is obtained by measuring the recorded adjustment pattern. Then, color correction parameters are generated based on the obtained information so that a desired color tone is recorded. The desired color tone can be recorded by correcting the image data using the color correction parameters.

[0080] FIG. 10A is a flowchart showing the color measurement process when color calibration is performed using a white recording medium in this embodiment.

[0081] In S1001, the CPU 102 executes a light amount adjustment process for the optical sensor 200 that uses the paper white portion of the recording medium.

[0082] In S1002, the CPU 102 executes a recording process using the image recording unit to record the adjustment pattern 400 on a recording medium.

[0083] Here, the configuration of the adjustment pattern 400 used in the color correction parameter generation process will be described with reference to Fig. 11. The adjustment pattern 400 recorded in S1002 described above is made up of patches of five colors: a K ink patch 401, a C ink patch 402, an M ink patch 403, a Y ink patch 404, and a W ink patch 405, and each color is made up of patches of 16 gradations.

[0084] The adjustment pattern 400 is not fixed to the recording medium immediately after printing the adjustment pattern 400. Therefore, in S1003, the CPU 102 feeds the recording medium so that the adjustment pattern 400 reaches the image fixing unit.

[0085] In S1004, the CPU 102 executes a fixing process for fixing the adjustment pattern 400 using the image fixing unit.

[0086] In S1005, the CPU 102 feeds the recording medium back so that the adjustment pattern 400 reaches the image recording unit. Note that, "backfeeding" refers to conveying the recording medium in the reverse direction. The reverse direction is the direction from the downstream side to the upstream side in the conveying direction, that is, the -Y direction (see FIG. 1, etc.).

[0087] In S1006, the CPU 102 executes a reading process of the adjustment pattern 400 using the optical sensor 200, and measures the density of each patch included in the adjustment pattern 400.

[0088] In this embodiment, since the optical sensor 200 is fixedly provided on the carriage 22, in S1005 it was necessary to backfeed the recording medium so that the adjustment pattern 400 reaches the image recording area recordable by the image recording unit. However, the location of the optical sensor is not limited to the carriage 22, and if the optical sensor is provided in another location, the recording medium is fed so that the adjustment pattern reaches the location where the optical sensor is provided.

[0089] In S1007, the CPU 102 stores the density values ​​of each patch, which are the measurement results, in the RAM 106 of the control unit 100, and the color measurement process in FIG. 10A ends.

[0090] FIG. 10(b) is a flowchart showing a process of generating color correction parameters based on the results of FIG. 10(a), correcting input image data by applying the generated color correction parameters, and recording an image based on the corrected input image data.

[0091] In S1011, the CPU 102 reads out from the RAM 106 the density values ​​acquired by the color measurement process of FIG.

[0092] In S1012, the CPU 102 generates color correction parameters for correcting the input image data based on the density values ​​acquired in S1011.

[0093] In S1013, the CPU 102 applies the color correction parameters generated in S1012 to the input image data to correct it. Through this step, the input image data can be corrected so that a reference color having a color target value is output.

[0094] In S1014, the CPU 102 executes a recording process based on the image data corrected in S1013.

[0095] As described above, by applying color correction parameters at any time as necessary, it is possible to always output stable images without color fluctuations.

[0096] As explained in the above-mentioned various adjustments (1) to (3), it is necessary to adjust the light amount of the optical sensor whenever making the adjustments. The light amount adjustment of the optical sensor is generally performed by performing white plate calibration, but in the recording device A, the light amount adjustment is performed by using a recording medium instead of a white plate. Therefore, if the recording medium is not white, it is not possible to perform appropriate light amount adjustment. For example, with a transparent recording medium with low optical reflectance, the projected light passes through the recording medium and does not return to the light receiving section, so it is not possible to perform appropriate light amount adjustment. With a colored recording medium, some wavelengths of light are absorbed and do not return to the light receiving section, so it is not possible to perform appropriate light amount adjustment.

[0097] Furthermore, the adjustment pattern is affected by the color of the background (recording medium), so the background needs to be a uniform white or black color. If the recording medium is transparent, the background color of the adjustment pattern is affected by the color of the platen 4 of recording device A. Because the platen 4 has an uneven shape, there are shadows caused by the unevenness, and the background color is not suitable for measurement, so appropriate measurement values ​​of the adjustment pattern cannot be obtained. Similarly, if the recording medium is colored, the color of the recording medium makes it impossible to obtain appropriate measurement values ​​of the adjustment pattern.

[0098] However, by using the characteristic configuration of this embodiment described below, more specifically by recording an adjustment pattern on top of a fixed base image, the above-mentioned adjustments (1) to (3) can be made possible even on transparent or colored recording media.

[0099] <Characteristic composition> The feature of this embodiment is that after the recording of the first image is completed using the first ink in the image recording unit, the first image is fixed in the image fixing unit described above, and then an adjustment pattern is recorded on the first image again in the image recording unit described above.

[0100] The adjustment pattern is a pattern used to adjust the print head and the printing device. After printing of the adjustment pattern is completed, the recorded adjustment pattern is read using an optical sensor. By reading the adjustment pattern recorded on the fixed first image, it is possible to obtain measurement values ​​with high accuracy regardless of the color of the recording medium, the reflectance of the optical sensor, or the color of the second ink used to print the adjustment pattern.

[0101] When the adjustment pattern is recorded on the first image, which serves as the base, using the above-mentioned low-permeability recording medium, if the first image is not fixed sufficiently, the first ink used to record the first image and the second ink used to record the adjustment pattern will mix. If the first ink and second ink mix, the second ink cannot be recorded in the appropriate position or dot shape.

[0102] Figure 12 is a schematic diagram showing a cross section of a second ink droplet recorded on a sufficiently fixed first ink layer (forming a first image). The first ink is dropped onto a recording medium P (Figure 12(a)), and when the first ink droplet on the recording medium P is fixed, it becomes a uniform layer Q (Figure 12(b)). A second ink droplet dropped onto the uniform ink layer Q (Figure 12(c)) can be spread evenly in a desired location (Figure 12(d)).

[0103] On the other hand, FIG. 13 is a schematic diagram showing a cross section of a second ink droplet recorded on an insufficiently fixed first ink layer (forming a first image). When the first ink is dropped onto a recording medium P (FIG. 13(a)), and then the second ink is dropped onto the insufficiently fixed first ink layer R (FIG. 13(b)), the state shown in FIG. 13(c) is obtained. FIG. 13(c) shows how the second ink droplet moves from the desired recording position or is buried as a result of dropping the second ink onto the insufficiently fixed first ink layer R. When the second ink droplet moves from the desired recording position or is buried in this way, the adjustment pattern cannot satisfy the accuracy required for adjustment of the recording head and the recording device, and the above-mentioned adjustments (1) to (3) cannot be performed with high accuracy.

[0104] Therefore, in order to perform an appropriate adjustment, it is necessary to print the adjustment pattern after the first image, which serves as the base, has been sufficiently fixed, as shown in FIG.

[0105] Hereinafter, one of the characteristic configurations of this embodiment, specifically, a method for performing registration adjustment of the print head and conveyance adjustment of the printing device using a transparent or colored printing medium, will be described.

[0106] In this embodiment, first, a base image (first image) is printed on the printing medium P with W ink, and after the printed image is sufficiently fixed, an adjustment pattern is printed on the base with color inks, i.e., K, C, M, and Y inks. In this way, even when a transparent or colored printing medium P is used, it is possible to adjust the positions of the K, C, M, and Y nozzles of the printing head.

[0107] Various recording media that can be used in recording device A are pre-classified into a first recording medium group and a second recording medium group based on optical reflectance and color. White recording media are classified into the first recording medium group, and transparent recording media and colored recording media are classified into the second recording medium group, and recording device A holds information on these recording medium groups. The technical features of this embodiment are realized by utilizing this recording medium group information (see FIG. 14).

[0108] 14 is a flowchart for when the above-mentioned (1) registration adjustment and (2) transport adjustment are performed. The process in FIG. 14 is started when the CPU 102 receives an instruction to start performing (1) registration adjustment and (2) transport adjustment for the print head.

[0109] First, in S1401, the CPU 102 judges whether the recording medium P to be recorded is included in the first recording medium group. If the judgment result in this step is true, the process proceeds to S1402. On the other hand, if the judgment result in this step is false (i.e., if the recording medium P is included in the second recording medium group), the process proceeds to S1403. Note that in this embodiment, the judgment in this step is performed using recording medium group information, but is not limited to this form. As another example, information indicating whether the recording medium P to be recorded belongs to the first recording medium group or the second recording medium group may be included in the print job acquired by the recording device, and the judgment in this step may be performed using this information. Alternatively, the user may select whether the recording medium P belongs to the first recording medium group or the second recording medium group.

[0110] In S1402, the CPU 102 executes the adjustment process, specifically, the processes of S801 to S807 shown in the flowchart of FIG.

[0111] In S1403, the CPU 102 records the background of the adjustment pattern, and then executes the adjustment process.

[0112] FIG. 15 shows a detailed flowchart of S1403.

[0113] First, in S1501, the CPU 102 executes a printing process for printing a base image (first image) with W ink by a multi-pass printing method using nozzles in all areas of the nozzle array 33W that ejects W ink shown in Fig. 3. In this example, the first image to be printed is an A4 size 200% solid image (1200 dpi with 1 dot being 100%).

[0114] In S1502, the CPU 102 feeds the recording medium so that the first image, which has been recorded (S1501), reaches the image fixing unit.

[0115] In S1503, CPU 102 causes the first image to be sufficiently fixed by exposing the first image to hot air at 80° C. In this embodiment, in order to "sufficiently fix" the first image, the first image is exposed to hot air at 80° C. for a preset predetermined time.

[0116] In S1504, the CPU 102 feeds the recording medium back so that the first image fixed in S1503 reaches the image recording unit.

[0117] In S1505, the CPU 102 executes the light amount adjustment process for the optical sensor using the first image printed with W ink.

[0118] In S1506, the CPU 102 executes the adjustment process, specifically, the processes of S802 to S807 shown in the flowchart of FIG.

[0119] The above-described processes of S1501 to S1505 are characteristic of this embodiment. These processes make it possible to perform appropriate adjustments required for (1) registration adjustment or (2) transport adjustment, even when using a transparent or colored low-permeability recording medium.

[0120] As described above, in this embodiment, the recording of the first image, which serves as the base, is completed and fixed by the image fixing unit. After that, the recording medium is fed back so that the first image reaches an image recording area where recording by the image recording unit is possible, and an adjustment pattern is recorded superimposed on the first image.

[0121] In the present embodiment, the recorded first image is fixed by an image fixing unit before the recording medium is fed backward, and from the viewpoint of transport accuracy during backward feeding, there is a risk that the recording start positions of the first image and the adjustment pattern may be misaligned. However, in this embodiment, the first image is recorded over the entire area that is the background of the adjustment pattern, so a slight misalignment of the recording start positions of the first image and the adjustment pattern does not cause a problem. From the above viewpoint, in the actual image recording mode in which an arbitrary image is recorded, rather than the adjustment pattern recording mode in which an adjustment pattern is recorded, the second image is recorded on the recorded first image without being fixed by the fixing unit.

[0122] As a method for minimizing the misalignment of the recording start positions between the first base image and the image to be overlaid on it, there is a multi-pass recording method in which different nozzle groups are used depending on the ink. In this multi-pass recording method, after recording of the base image, another arbitrary image is recorded on the base image without fixing in the image fixing unit.

[0123] Below, a case in which printing of images with W ink and K ink is completed in six scans in a predetermined area will be described with reference to FIG. 16 as a flowchart of a multi-pass printing method in which different nozzle groups are used depending on the ink.

[0124] First, in S1601, an image is printed using W ink in the first to third scans. The print data for W ink is distributed so that the printing of the image is completed in the first to third scans, and when the third scan ends, the printing of the image with W ink is completed.

[0125] Next, in S1602, an image is printed using K ink in the fourth to sixth scans. The K ink print data is distributed so that printing of the image is completed in the fourth to sixth scans. In the fourth to sixth scans, the K ink image is printed on top of the W ink image that has been printed in the first three scans. When the sixth scan ends, printing of the K ink image is completed, and printing of the K ink image on the W ink image in the specified area is completed.

[0126] In S1603, the CPU 102 feeds the recording medium so that the completely recorded image reaches the image fixing unit.

[0127] In S1604, the CPU 102 executes a fixing process for fixing the image on the recording medium using the image fixing unit.

[0128] In the recording method shown in FIG. 16, there is no need to backfeed the recording medium when recording an image over an underlying image, so there is little misalignment between the underlying image and the image recorded on top of it, resulting in a high-quality image.

[0129] However, in the multi-pass printing method in which different nozzle groups are used depending on the ink, it is not possible to fix only the base image in the image fixing unit. Therefore, there is a risk of the ink (first ink) for recording the base image and the ink (second ink) for recording the image to be overlaid on the base being mixed. Therefore, in order to prevent the first ink and the second ink from mixing, it is necessary to slow down the print scan speed and dry the first ink to some extent during the print scan.

[0130] For these reasons, the multi-pass printing method is usually adopted when a base image is required and when printing an image that requires high image quality rather than a reduction in printing time.

[0131] As mentioned above, when printing an adjustment pattern, there is no need to align the base image area and the adjustment pattern image area with high precision, so the printing method described in this embodiment is adopted to shorten the adjustment time.

[0132] In this manner, in this embodiment, a base image is recorded on the recording medium P with W ink, and after the W ink image has been sufficiently fixed, an adjustment pattern is recorded on the base with K, C, M, and Y inks. The recorded adjustment pattern is then read. With this configuration, it becomes possible to measure the density difference caused by the amount of shift between the reference pattern and the shift pattern of K, C, M, and Y inks, and to perform registration adjustment and transport adjustment of the K, C, M, and Y nozzles of the recording head.

[0133] [Second embodiment] In this embodiment, a method of performing color calibration using a transparent or colored recording medium will be described. The feature of this embodiment is that the fixing timing of the adjustment pattern is different from that of the first embodiment.

[0134] As explained in (1) registration adjustment and (2) transport adjustment in the first embodiment, the timing for fixing the adjustment pattern differs between registration adjustment or transport adjustment and color calibration. In detail, in registration adjustment or transport adjustment, after the adjustment pattern is read in S803, the adjustment pattern is finally fixed in S807 (see FIG. 8). On the other hand, in color calibration, after the adjustment pattern is fixed in S1004, the adjustment pattern is read in S1006 (see FIG. 10).

[0135] When performing color calibration, it is important that the color of the adjustment pattern is stable, so the ink used to record the adjustment pattern must be sufficiently dried. For this reason, the adjustment pattern is fixed in an image fixing unit before being read.

[0136] On the other hand, in the registration adjustment or transport adjustment, as shown in Figures 7(a), 7(b), 9(a), and 9(b), the density caused by the misalignment between the reference pattern and the shift pattern of the adjustment pattern is measured, so there is no need to stabilize the color of the adjustment pattern. Therefore, in order to further shorten the adjustment time, the adjustment pattern is fixed after reading the adjustment pattern. When fixing is performed after reading the adjustment pattern, there is no need to perform S1005 (backfeed process) shown in Figure 10, so the adjustment time can be shortened.

[0137] In this embodiment, first, a base image (first image) is printed with W ink on a transparent or colored recording medium P, and after the W ink image is sufficiently fixed, the adjustment pattern shown in Fig. 11 is printed on the base with K, C, M, and Y inks. In this way, even when a transparent or colored recording medium P is used, color calibration can be performed on the K nozzles, C nozzles, M nozzles, and Y nozzles in the recording head.

[0138] Various recording media that can be used in recording device A are pre-classified into either a first recording medium group or a second recording medium group based on optical reflectance and color. Specifically, white recording media are classified into the first recording medium group, and transparent recording media and colored recording media are classified into the second recording medium group, and recording device A holds information on these recording medium groups. The technical features of this embodiment are realized by utilizing this recording medium group information.

[0139] 14 is a flowchart of the process when color calibration is performed in this embodiment. This process is similar to the flowchart of the process when registration adjustment or transport adjustment is performed in the first embodiment.

[0140] First, in S1401, the CPU 102 determines whether the recording medium P to be recorded is included in the first recording medium group. If the determination result in this step is true, the process proceeds to S1402. On the other hand, if the determination result in this step is false, the process proceeds to S1403.

[0141] In S1402, the CPU 102 executes the adjustment process, specifically, the processes of S1001 to S1007 shown in the flowchart of FIG.

[0142] In S1403, the CPU 102 records the background of the adjustment pattern, and then executes the adjustment process.

[0143] A detailed flowchart of S1403 is shown in Fig. 15. Fig. 15 is a flowchart explained in the first embodiment, and the same flowchart will be used in the second embodiment.

[0144] First, in S1501, the CPU 102 executes a printing process for printing a base image (first image) with W ink by a multi-pass printing method using nozzles in all areas of the nozzle array 33W that ejects W ink shown in Fig. 3. In this example, the first image to be printed is an A4 size 200% solid image (1200 dpi with 1 dot being 100%).

[0145] In S1502, the CPU 102 feeds the recording medium so that the first image, which has been recorded (S1501), reaches the image fixing unit.

[0146] In S1503, CPU 102 causes the first image to be sufficiently fixed by exposing the first image to hot air at 80° C. In this embodiment, in order to "sufficiently fix" the first image, the first image is exposed to hot air at 80° C. for a preset predetermined time.

[0147] In S1504, the CPU 102 feeds the recording medium back so that the first image fixed in S1503 reaches the image recording unit.

[0148] In S1505, the CPU 102 executes the light amount adjustment process for the optical sensor using the first image printed with W ink.

[0149] In S1506, the CPU 102 executes the adjustment process, specifically, the processes of S1002 to S1007 shown in the flowchart of FIG.

[0150] The above-described processes in S1501 to S1505 are characteristic of this embodiment. These processes enable appropriate adjustments required for performing color calibration, even when a transparent or colored low-permeability recording medium is used.

[0151] It should be noted that if the color of the recording medium or the first image that serves as the background is white, it is not possible to obtain measurement values ​​for patches printed with W ink. Taking this into consideration, in this embodiment, adjustment of the W nozzles that eject W ink is not performed. The adjustment pattern 400 used in this embodiment includes a patch 405 of W ink, but the adjustment pattern 400 is not read for the patch 405 in S1006. Alternatively, the adjustment pattern to be printed may be patches 401 to 404 so as not to include the patch 405.

[0152] So far, in this embodiment, as in the first embodiment, it has been explained that after completing the recording of the first image that serves as the base and fixing it in the image fixing section, the recording medium is fed back so that the first image reaches the image recording section, and an adjustment pattern is recorded superimposed on top of the first image.

[0153] In a specification in which the recorded first image is fixed in the image fixing section and then the recording medium is fed back so that the first image reaches the image recording area, there is a risk that the recording start positions of the first image and the adjustment pattern may be misaligned from the viewpoint of conveyance accuracy during the backfeed. However, since the first image is recorded as a base over the entire area that is the background of the adjustment pattern, a slight misalignment of the recording start positions of the first image and the adjustment pattern does not cause a problem. Therefore, as described in the first embodiment, it is possible to fix the first image in the image fixing section, and the adjustment time can be shortened.

[0154] On the other hand, in recording an arbitrary image, a method in which a first image is fixed in an image fixing section, the recording medium is fed back, and a second image is recorded on the first image in an image recording section is not preferable from the viewpoint of image quality, as described in the first embodiment. Therefore, the method for recording an arbitrary image is the same as in the first embodiment.

[0155] In this manner, in this embodiment, a base image is recorded on recording medium P with W ink, and after the W ink image has been sufficiently fixed, an adjustment pattern is recorded on the base with K, C, M, and Y inks. The recorded adjustment pattern is then fixed and read. With this configuration, it becomes possible to measure the density difference caused by the difference in the exposure amount of the base W ink depending on the amount of K, C, M, and Y ink, and color calibration of the K, C, M, and Y nozzles of the print head can be performed.

[0156] [Third embodiment] In this embodiment, a method for performing color calibration of W ink (also called white ink) ejected from W nozzles will be described. The density difference of a patch of W ink printed on a white printing medium cannot be measured because the ink and the printing medium are the same color. In addition, the density difference of a patch of W ink printed on a transparent printing medium cannot be measured because it is affected by the color of the platen 4.

[0157] Therefore, in this embodiment, first, an image (first image) that will serve as a base is recorded on the recording medium P with K ink (also called black ink), and after the K ink image has been sufficiently fixed, an adjustment pattern is recorded on the base with W ink. This makes it possible to measure the density difference caused by the difference in the amount of exposure of the K ink of the base depending on the amount of W ink, and allows color calibration of the W ink to be performed. Note that, although K ink, which has high light absorption characteristics, is preferable as the ink for recording the base, it is not limited to K ink. Other inks (for example, C ink) can also be used as long as the desired density difference can be measured.

[0158] 17 is a flowchart of the color calibration of the W ink in this embodiment. In the color calibration of the W ink, regardless of the type of recording medium P, the base of the adjustment pattern is always recorded.

[0159] First, in S1701, the CPU 102 uses all the nozzles in the nozzle array 33K that ejects the K ink shown in Fig. 3 to print a base image (first image) in K ink by a multi-pass printing method. At the same time, a light amount adjustment image for performing light amount adjustment is printed using all the nozzles in the nozzle array 33W that ejects the W ink, aligned in the main scanning direction with respect to the first image. In this example, the first image and the light amount adjustment image to be printed are A4 size 200% solid images (1200 dpi with 1 dot being 100%).

[0160] In S1702, the CPU 102 feeds the recording medium so that the first image and the image for light amount adjustment that have been recorded (S1701) reach the image fixing unit.

[0161] In S1703, the CPU 102 causes the first image and the image for light amount adjustment to be sufficiently fixed by exposing them to hot air at 80° C. In this embodiment, in order to "sufficiently fix," the first image and the image for light amount adjustment are exposed to hot air at 80° C. for a predetermined time.

[0162] In S1704, the CPU 102 feeds the recording medium back so that the first image and the light amount adjustment image fixed in S1703 reach the image recording unit.

[0163] In S1705, the CPU 102 executes the light amount adjustment process for the optical sensor using the light amount adjustment image printed with W ink.

[0164] In S1706, the CPU 102 executes the adjustment process, specifically, the processes of S1002 to S1007 shown in the flowchart of FIG.

[0165] The above-described processing of S1701 to S1705 is a characteristic configuration of this embodiment. This processing enables appropriate adjustment for color calibration of W ink.

[0166] Incidentally, the adjustment pattern 400 used in this embodiment includes patches 401 to 404 other than the W ink, but the adjustment pattern 400 is not read in S1006 for the patches 401 to 404. Alternatively, the adjustment pattern to be printed may be only the W ink patch 405.

[0167] In addition, in this embodiment, the light amount adjustment of the optical sensor is performed using a light amount adjustment image recorded with W ink, but other methods may be used. For example, if a white plate is installed in the recording device, the white plate may be used. Also, if the recording medium is white, the recording medium may be used. In this case, it is not necessary to record a light amount adjustment image.

[0168] In this manner, in this embodiment, a base image is recorded on the recording medium P with K ink, and after the K ink image has been sufficiently fixed, an adjustment pattern is recorded on the base with W ink. The recorded adjustment pattern is then fixed and read. With this configuration, it becomes possible to measure the density difference caused by the difference in the amount of exposure of the base K ink depending on the amount of W ink, and color calibration of the W ink can be performed.

[0169] [Other embodiments] In the above embodiment, recording medium group information for classifying recording media into groups (first recording medium group, second recording medium group) is stored in advance, and this recording medium group information is used to determine whether to record the background of the adjustment pattern. However, the present disclosure is not limited to this form, and recording medium group information may not be stored. For example, a user may select which recording medium group the recording medium to be recorded belongs to. Also, for example, an optical sensor installed in the recording device may measure the reflectance of the recording medium, and automatic selection may be made based on the measured reflectance. As an example of automatic selection based on reflectance, a threshold value for reflectance is set to 0.5, and if the measured reflectance is equal to or greater than the threshold, a process for the first recording medium group is selected, and if the measured reflectance is less than the threshold, a process for the second recording medium group is selected. Also, for example, an optical sensor installed in the recording device may measure the color of the recording medium, and automatic selection may be made based on the measured color.

[0170] In the above embodiment, a multi-pass printing method is used as the printing method for the first image, which is the base, but the printing method is not limited to the multi-pass method. For example, depending on the ink, adjustment pattern, etc., printing of the base image may be completed in one scan. If the image printing is completed with fewer scans, the image printing time is shortened, and therefore the adjustment time can be shortened.

[0171] Furthermore, in the above embodiment, the first image, which is the background of the adjustment pattern, is a 200% solid image (1 dot at 1200 dpi is 100%), but the first image is not limited to a 200% solid image.

[0172] Depending on the adjustment pattern, it may be possible to obtain an adjustment value even with a first image with a lower print duty%. Therefore, the print duty% may be set appropriately. For example, depending on the adjustment pattern, the print duty% of the first image serving as the background for the adjustment pattern may be lower than the print duty% of the first image serving as the background for any image. The lower the print duty% of the first image serving as the background for the adjustment pattern, the shorter the fixing time of the first image can be, and therefore the shorter the adjustment time. Note that print duty refers to the amount of ink applied per unit area.

[0173] In the above embodiment, the first image, which is the background of the adjustment pattern, is A4 size, but the size of the first image is not limited to A4 size. The size of the background first image may be changed appropriately according to the size of the adjustment pattern, as long as it is large enough to serve as the background of the adjustment pattern. If the recording area of ​​the adjustment pattern is small, the first image may also be made small. The smaller the first image to be recorded, the shorter the recording time of the first image and the fixing time of the first image, and therefore the adjustment time can be shortened.

[0174] In addition, although density values ​​are obtained by the optical sensor 200 as measurement values ​​of the adjustment pattern in various adjustments such as registration adjustment, transport adjustment, and color calibration, the measurement values ​​are not limited to density values. For example, it is also possible to use a colorimeter capable of obtaining color values ​​to obtain the CMYK values, L*a*b* values, XYZ values, and RGB values ​​of the pattern.

[0175] Furthermore, even when adjusting the light intensity using a white plate that is used in general light intensity adjustment, appropriate measurement values ​​cannot be obtained due to the influence of the background color of the adjustment pattern described above, so by applying the characteristic configuration of the present disclosure, appropriate adjustment is possible.

[0176] [Technical Features of the Disclosure] The present disclosure includes the following configurations. (Configuration 1) A recording device comprising: a transport means for transporting a recording medium; and a recording means having a recording head and for recording an image, the recording head having a first nozzle for ejecting a first liquid containing a white coloring material and a second nozzle for ejecting a second liquid, the image including an adjustment pattern; a reading means for reading the image recorded on the recording medium; a fixing means for fixing the image recorded by the recording means to the recording medium; and an adjustment means for performing adjustment based on a result of reading the adjustment pattern by the reading means, wherein after a first image as a base recorded by the recording means using the first liquid or the second liquid is fixed by the fixing means, the recording means records the adjustment pattern on the first image using the liquid of the first liquid or the second liquid that was not used in recording the first image. (Configuration 2) The recording apparatus according to configuration 1, wherein the adjustment is registration adjustment, transport adjustment, or color calibration. (Configuration 3) The recording device according to configuration 1 or 2, wherein the first image is recorded with the first liquid, and the adjustment pattern is recorded with the second liquid. (Configuration 4) A recording device described in any one of configurations 1 to 3, characterized in that the recording means, the reading means, and the fixing means are provided in this order from upstream to downstream in a conveying direction by the conveying means, and after the first image is fixed by the fixing means, the recording medium is back-fed by the conveying means, so that the first image reaches a recording area where the recording means can record. (Configuration 5) In the recording apparatus according to any one of configurations 1 to 4, after the adjustment pattern is fixed by the fixing means, the adjustment pattern is read by the reading means. (Configuration 6) The recording device according to any one of configurations 1 to 5, further comprising: an acquisition means for acquiring a density value based on a result of reading the adjustment pattern; and a calculation means for calculating an adjustment value based on the density value. (Structure 7) A recording device as described in any one of structures 1 to 6, further comprising a determination means for determining whether the recording medium is included in a first recording medium group or a second recording medium group, wherein a white recording medium is classified into the first recording medium group, and a transparent recording medium and a colored recording medium are classified into the second recording medium group. (Configuration 8) The recording device according to any one of configurations 1 to 7, further comprising a storage means for storing recording medium group information, wherein the determination means makes a determination based on the recording medium group information. (Configuration 9) A recording device according to any one of configurations 1 to 8, further comprising a measuring means for measuring the reflectance of the recording medium, and the judgment means makes a judgment based on whether the measured value obtained by the measuring means is equal to or greater than a threshold value. (Configuration 10) The recording device according to any one of configurations 1 to 9, further comprising a measuring means for measuring a color tone of the recording medium, and the judgment means makes a judgment based on the color tone obtained by the measuring means. (Configuration 11) A recording device described in any one of configurations 1 to 10, characterized in that, when the determination means determines that the recording medium is included in the second recording medium group, recording of the first image by the recording means, fixing of the first image by the fixing means, and recording of the adjustment pattern by the recording means are executed, and when the determination means determines that the recording medium is included in the first recording medium group, recording of the adjustment pattern by the recording means is executed without recording of the first image by the recording means. (Configuration 12) The recording apparatus according to any one of configurations 1 to 11, wherein the determination is made by the determining means when the adjustment is a registration adjustment or a transport adjustment. (Configuration 13) The recording device according to any one of configurations 1 to 12, characterized in that the recording medium is a transparent or colored recording medium, and the judgment is made by the judgment means when the adjustment is color calibration. (Configuration 14) The recording device according to any one of configurations 1 to 13, wherein the first image is recorded by the second liquid, and the adjustment pattern is recorded by the first liquid. (Configuration 15) A recording device according to any one of configurations 1 to 14, characterized in that the first liquid is white ink, the second liquid is black ink containing black colorant, and the adjustment is color calibration of the white ink. (Configuration 16) A recording device described in any one of configurations 1 to 15, characterized in that the first image is recorded by the recording means using the black ink, and the image for adjusting the light amount is recorded by the recording means using the white ink. (Configuration 17) The recording device according to any one of configurations 1 to 16, further comprising an execution unit that executes a light amount adjustment process for the reading unit by using the image for adjusting the light amount. (Configuration 18) The recording device according to any one of configurations 1 to 17, characterized in that the amount of the first liquid applied per unit area is less when recording the adjustment pattern than when recording an arbitrary image. (Configuration 19) The recording device according to any one of configurations 1 to 18, characterized in that in an actual image recording mode in which an arbitrary image is recorded rather than an adjustment pattern recording mode in which the adjustment pattern is recorded, the recording means records a second recording medium on the first image without fixing the first image to the recording medium by the fixing means. (Configuration 20) The recording apparatus according to any one of configurations 1 to 19, wherein a nozzle group for ejecting the first liquid and a nozzle group for ejecting the second liquid are made different from each other. (Configuration 21) The recording apparatus according to any one of configurations 1 to 20, further comprising control means for controlling the recording means, the transport means, the reading means, and the fixing means. (Configuration 22) A control method for a recording device having a transport means for transporting a recording medium, and a recording means having a recording head and recording an image, the recording head having a first nozzle for ejecting a first liquid containing a white colorant and a second nozzle for ejecting a second liquid, the image including an adjustment pattern, a reading means for reading the image recorded on the recording medium, a fixing means for fixing the image recorded by the recording means to the recording medium, and an adjustment means for performing adjustment based on a result of reading the adjustment pattern by the reading means, the control method comprising: a recording step of recording a first image as a base using the first liquid or the second liquid by the recording means, a fixing step of fixing the first image to the recording medium by the fixing means, and a recording step of recording the adjustment pattern on the first image by the recording means using the first liquid or the second liquid that was not used in recording the first image. (Configuration 23) A control method for a recording device having a transport means for transporting a recording medium, a recording means having a recording head and recording an image, the recording head having a first nozzle for ejecting a first liquid containing a white coloring material and a second nozzle for ejecting a second liquid, the image including an adjustment pattern, a reading means for reading the image recorded on the recording medium, a fixing means for fixing the image recorded by the recording means to the recording medium, and an adjustment means for performing adjustment based on a result of reading the adjustment pattern by the reading means, the control method comprising: a recording step of recording a first image as a base using the first liquid or the second liquid by the recording means; a fixing step of fixing the first image to the recording medium by the fixing means; and a recording step of recording the adjustment pattern on the first image by the recording means using the first liquid or the second liquid that was not used in recording the first image. [Explanation of symbols]

[0177] P Recording medium 9. Recording Head 10. Heater 102 CPU 118 Motor 200 Optical Sensor

Claims

1. A conveying means for conveying a recording medium; a recording means having a recording head and configured to record an image, the recording head having a first nozzle for ejecting a first liquid containing a white coloring material and a second nozzle for ejecting a second liquid, the image including an adjustment pattern; a reading means for reading the image recorded on the recording medium; a fixing means for fixing the image recorded by the recording means onto the recording medium; an adjustment means for performing an adjustment based on a result of reading the adjustment pattern by the reading means; having a first image as a base recorded by the recording means using the first liquid or the second liquid is fixed by the fixing means, and then the adjustment pattern is recorded by the recording means on the first image using the liquid not used in recording the first image out of the first liquid or the second liquid. A recording apparatus comprising:

2. The adjustment is a registration adjustment, a transport adjustment, or a color calibration.

2. The recording apparatus according to claim 1,

3. the first image is recorded with the first liquid, and the adjustment pattern is recorded with the second liquid.

3. The recording apparatus according to claim 1, wherein the recording medium is a recording medium.

4. the recording means, the reading means, and the fixing means are provided in this order from the upstream side to the downstream side in a conveying direction of the conveying means, after the first image is fixed by the fixing means, the recording medium is fed back by the conveying means, so that the first image reaches a recording area where the recording means can record.

4. The recording apparatus according to claim 3.

5. After the adjustment pattern is fixed by the fixing means, The adjustment pattern is read by the reading means.

5. The recording apparatus according to claim 4.

6. an acquisition means for acquiring a density value based on a result of reading the adjustment pattern; A calculation means for calculating an adjustment value based on the concentration value; Further comprising 6. The recording apparatus according to claim 5.

7. The method further includes a determination unit for determining whether the recording medium is included in a first recording medium group or a second recording medium group, The white recording medium is classified into the first recording medium group, and the transparent recording medium and the colored recording medium are classified into the second recording medium group.

4. The recording apparatus according to claim 3.

8. The recording medium group information storing device further includes a storage means for storing the recording medium group information, The determination means makes a determination based on the recording medium group information.

8. The recording apparatus according to claim 7.

9. The recording medium further includes a measuring means for measuring a reflectance of the recording medium, The determination means makes a determination based on whether the measurement value acquired by the measurement means is equal to or greater than a threshold value.

8. The recording apparatus according to claim 7.

10. The method further comprises a measuring means for measuring a color tone of the recording medium, The determining means determines based on the color acquired by the measuring means.

8. The recording apparatus according to claim 7.

11. when the determination means determines that the recording medium is included in the second recording medium group, the recording means records the first image, the fixing means fixes the first image, and the recording means records the adjustment pattern, when the determination means determines that the recording medium is included in the first recording medium group, the recording means performs recording of the adjustment pattern without recording the first image by the recording means.

11. The recording apparatus according to claim 10.

12. When the adjustment is a registration adjustment or a transport adjustment, the determination is made by the determination means.

12. The recording apparatus according to claim 11.

13. the recording medium is a transparent or colored recording medium, and the determination by the determination means is made when the adjustment is color calibration; 12. The recording apparatus according to claim 11.

14. the first image is recorded by the second liquid, and the adjustment pattern is recorded by the first liquid.

4. The recording apparatus according to claim 3.

15. the first liquid is white ink, the second liquid is a black ink containing a black coloring material, The adjustment is a color calibration of white ink.

15. The recording apparatus according to claim 14.

16. the first image is recorded by the recording means using the black ink; the recording means records an image for adjusting a light amount using the white ink; 16. The recording apparatus according to claim 15.

17. The light amount adjustment method further includes: an execution unit that executes a light amount adjustment process for the reading unit by using the light amount adjustment image; 17. The recording apparatus according to claim 16.

18. Regarding the amount of the first liquid applied per unit area, when the adjustment pattern is recorded, the amount is less than when an arbitrary image is recorded.

4. The recording apparatus according to claim 3.

19. In a real image recording mode in which an arbitrary image is recorded, not in an adjustment pattern recording mode in which the adjustment pattern is recorded, the second image is recorded on the first image by the recording means without fixing the first image on the recording medium by the fixing means.

4. The recording apparatus according to claim 3.

20. a nozzle group for ejecting the first liquid and a nozzle group for ejecting the second liquid are made different from each other; 20. The recording apparatus according to claim 19.

21. The recording device further includes a control unit that controls the recording unit, the conveying unit, the reading unit, and the fixing unit.

4. The recording apparatus according to claim 3.

22. A conveying means for conveying a recording medium; a recording means having a recording head and configured to record an image, the recording head having a first nozzle for ejecting a first liquid containing a white coloring material and a second nozzle for ejecting a second liquid, the image including an adjustment pattern; a reading means for reading the image recorded on the recording medium; a fixing means for fixing the image recorded by the recording means onto the recording medium; an adjustment means for performing an adjustment based on a result of reading the adjustment pattern by the reading means; A method for controlling a recording device comprising: a recording step of recording a first image as a base using the first liquid or the second liquid by the recording means; a fixing step of fixing the first image onto the recording medium by the fixing means; a recording step of recording the adjustment pattern on the first image by the recording means using the liquid not used in recording the first image out of the first liquid or the second liquid; A control method comprising:

23. A program for causing a computer to execute the method according to claim 22.

Images