Recording device and recording method

Abstract

To provide a recording device having a recording mode that is excellent in a recording speed and image quality.SOLUTION: A recording device comprises: a while ink jet head; a non-white ink jet head; and a control part which performs control for executing recording by performing main scanning for discharging ink compositions from the ink jet heads and causing the ink compositions to adhere to a recording medium multiple times while moving the positions of the ink jet heads relative to the recording medium. The control part executes recording of a first mode for causing a white ink composition and a non-white ink composition to adhere to the same scanning area of the recording medium by same main scanning, and recording of a second mode for causing the white ink composition and the non-white ink composition to adhere to the same scanning area of the recording medium by different main scannings.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a recording apparatus and a recording method. [Background technology]

[0002] Inkjet recording methods are capable of recording high-definition images with a relatively simple device, and have made rapid developments in various fields. In the process, various studies have been made on improving image quality, etc. For example, Patent Document 1 discloses an image recording method for the purpose of providing an image recording method capable of obtaining high-quality images with suppressed bleeding, the image recording method comprising a first step of recording an underlayer on a substrate with an ink composition for forming an underlayer, and a second step of recording a color image layer on the underlayer with a process color ink composition in a state in which the remaining amount of volatile components in the underlayer is 5 to 50% by mass. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-158884 A Summary of the Invention [Problem to be solved by the invention]

[0004] As described in Patent Document 1, by recording a base layer and then recording a color image layer, there is an advantage that a recorded matter with good visibility of the color image can be obtained. On the other hand, in the method of laminating a base layer and a color image layer in this way, there is a problem that the recording speed is slower by the amount required for lamination and a large head is required. In addition, there is a problem that excellent image quality cannot be obtained when a large head is not required or when an excellent recording speed is achieved. [Means for solving the problem]

[0005] The present invention is a recording device for recording on a recording medium, the recording device comprising: a white inkjet head that ejects a white ink composition containing a white coloring material to adhere to the recording medium; a non-white inkjet head that ejects a non-white ink composition containing a non-white coloring material to adhere to the recording medium; and a control unit that controls recording by performing a main scan multiple times to eject the ink composition from the inkjet head and adhere it to the recording medium while moving the position of the inkjet head relative to the recording medium, wherein the control unit performs recording in a first recording mode in which the white ink composition and the non-white ink composition are deposited on the same scanned region of the recording medium by the same main scan to form a layer containing the white ink composition and the non-white ink composition, and recording in a second recording mode in which the white ink composition and the non-white ink composition are deposited on the same scanned region of the recording medium by different main scans to form a layer containing the white ink composition and a layer containing the non-white ink composition by laminating them.

[0006] The present invention is a recording method using the inkjet recording apparatus, which comprises selecting either the first recording mode or the second recording mode, and performing recording in the selected recording mode. [Brief description of the drawings]

[0007] [Figure 1] 2 shows an example of a recording device used in this embodiment. [Diagram 2] 2 shows an example of the configuration of an inkjet head. [Diagram 3] 2 shows an example of the configuration of an inkjet head. [Figure 4] 4 shows an example of a flowchart of control of the printing method of the present embodiment. [Diagram 5] 2 shows an example of a recording device used in this embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary, but the present invention is not limited to this, and various modifications are possible without departing from the gist of the present invention. In the drawings, the same elements are given the same reference numerals, and duplicated explanations will be omitted. Furthermore, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings, unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to those shown in the drawings.

[0009] In this embodiment, when there is no particular distinction between a white inkjet head and a non-white inkjet head, they are simply referred to as "inkjet heads." Similarly, when there is no particular distinction between a white ink composition and a non-white ink composition, they are simply referred to as "ink compositions."

[0010] Moreover, the term "main scanning" refers to an operation of ejecting an ink composition from the inkjet head and depositing it on the recording medium while moving the position of the inkjet head relative to the recording medium. The inkjet head can be mounted on, for example, a carriage. The inkjet head may be moved by moving the carriage, and in this case, the movement is also referred to as the movement of the inkjet head.

[0011] Moreover, the term "main scanning direction" refers to the direction of movement of the inkjet head, which is the width direction of the recording medium. Note that "main scanning" refers to the movement of the position of the inkjet head relative to the recording medium, and the inkjet head may move relative to the recording medium, or the recording medium may move relative to the inkjet head. The direction of such relative position movement is the main scanning direction. The movement of the position of the inkjet head relative to the recording medium can also be referred to as the movement of the position of the recording medium relative to the inkjet head. In other words, it is the movement of the relative positions of the inkjet head and the recording medium.

[0012] On the other hand, the term "sub-scanning" refers to the operation of moving the relative positions of the inkjet head and the recording medium in the sub-scanning direction, which is a direction that intersects with the main scanning direction. For example, the ink composition is deposited on a certain area of ​​the recording medium in a main scan, the recording medium is moved slightly in a sub-scan, and then the next main scan is performed to deposit the ink composition adjacent to or partially overlapping the previously deposited ink composition. This operation is repeated to perform recording. Note that "sub-scan" also refers to the movement of the position of the inkjet head relative to the recording medium, and the inkjet head may move relative to the recording medium, or the recording medium may move relative to the inkjet head. The direction of such relative movement is the sub-scan direction.

[0013] Printing can be performed by performing main scanning and sub-scanning multiple times, for example by repeatedly performing main scanning and sub-scanning alternately.

[0014] 1. Recording device The recording apparatus of the present embodiment is a recording apparatus that records on a recording medium, and is equipped with a white inkjet head that ejects a white ink composition containing a white coloring material to adhere to the recording medium, a non-white inkjet head that ejects a non-white ink composition containing a non-white coloring material to adhere to the recording medium, and a control unit that controls recording by performing main scanning multiple times to eject the ink composition from the inkjet head and adhere it to the recording medium while moving the position of the inkjet head relatively to the recording medium, and the control unit executes a first recording mode in which the white ink composition and the non-white ink composition are deposited on the same scanned area of ​​the recording medium by the same main scanning to form a layer containing the white ink composition and the non-white ink composition, and a second recording mode in which the white ink composition and the non-white ink composition are deposited on the same scanned area of ​​the recording medium by different main scanning to form a layer containing the white ink composition and a layer containing the non-white ink composition by stacking them.

[0015] In the past, a white ink layer and a non-white ink layer were formed by stacking them, and the white ink layer was used as a concealing layer to record a high-quality image. However, when the white ink layer and the non-white ink layer are formed by stacking them, there is a problem that the recording speed decreases accordingly. The present inventors have studied this point and found that even if the white ink layer and the non-white ink layer are not formed by stacking them as in the past, a recorded matter in which a single ink layer containing a white ink composition and a non-white ink composition is formed on a recording medium can be an image with excellent color development without unevenness in shading.

[0016] Therefore, in this embodiment, it is possible to execute a first recording mode in which the white ink composition and the non-white ink composition are deposited on the same scanning area of ​​the recording medium by the same main scan, and a second recording mode in which the colored ink compositions and the non-white ink compositions are deposited on the same scanning area of ​​the recording medium by different main scans.

[0017] That is, it is possible to execute a first recording mode in which an image is formed with a single ink layer containing a white ink composition and a non-white ink composition with emphasis on recording speed, and a second recording mode in which an image is formed by overlapping a white ink layer and a non-white ink layer as in the conventional method with emphasis on image quality. In other words, it is possible to execute recording performed in the first recording mode and recording performed in the second recording mode.

[0018] An example of a recording apparatus used in the present embodiment will be described below with reference to the drawings, but the recording apparatus used in the present embodiment is not limited to the following aspect.

[0019] An example of a recording device used in this embodiment is shown in Fig. 1. Fig. 1 explains an example of an on-carriage type printer in which an ink cartridge is mounted on a carriage, but the recording device is not limited to an on-carriage type printer, and may be an off-carriage type printer in which the ink cartridge is fixed externally. In the case of an off-carriage type, the ink cartridge 3 is mounted in a location other than the carriage 4, and ink is supplied from the ink cartridge 3 to the recording head 2 via an ink supply pipe.

[0020] The printer used in the following description is a serial printer in which an inkjet head for recording is mounted on a carriage that moves in a predetermined direction, and the inkjet head moves with the movement of the carriage to eject droplets onto the recording medium. The serial type may be a type in which main scanning is performed in a direction intersecting the sub-scanning direction, which is the feed direction of the recording medium, or a lateral type in which the inkjet head moves alternately in the main scanning direction and the sub-scanning direction relative to a fixed recording medium.

[0021] As shown in FIG. 1, the printer 1 includes a recording head 2, an ink cartridge 3, a carriage 4, a platen 5, a heating mechanism 6, a carriage movement mechanism 7, a medium feed mechanism 8, a guide rod 9, a linear encoder 10, and a control unit CONT.

[0022] 1.1.Inkjet head The recording head 2 is a means for depositing each ink composition on the recording medium M, and is provided with a first nozzle for ejecting a white ink composition and a second nozzle for ejecting a non-white ink composition on the surface facing the recording medium M to which each ink composition is deposited. These multiple nozzles are arranged in a row, thereby forming a nozzle surface on the surface of the nozzle plate. In FIG. 1, the recording head 2 serves as both a white inkjet head and a non-white inkjet head.

[0023] Examples of the method for ejecting the white ink composition or the non-white ink composition from the nozzle include a piezoelectric method in which pressure and a recording information signal are simultaneously applied to the white ink composition or the non-white ink composition by a piezoelectric element, thereby ejecting and recording droplets of the ink or the non-white ink composition. In addition to an inkjet head, a dot impact head, a thermal transfer head, or the like may also be used as the recording head 2.

[0024] In addition, the inkjet head of the present embodiment can have a head configuration in which nozzles for ejecting a white ink composition and nozzles for ejecting a non-white ink composition are arranged side by side so that the deposition of the white ink composition and the deposition of the non-white ink compositions are performed to the same scanning area of ​​the recording medium by the same relative scanning. Therefore, it is possible to reduce the overall size of the inkjet head compared to a head configuration based on a conventional lamination.

[0025] 2 and 3 show the nozzle formation surface of the recording head 2. In the recording device of this embodiment, the control unit CONT controls the nozzles of the recording head 2, so that the recording device can execute both the first recording mode and the second recording mode using one recording head 2.

[0026] Nozzle control of the recording head 2 when performing the first recording mode will be described with reference to Figure 2. In the inkjet head shown in Figure 2, the ink composition is ejected from the entire nozzle row in the sub-scanning direction SS. When scanning is performed by ejecting a white ink composition from the nozzle row N1 and ejecting a non-white ink composition from the nozzle row N2, the nozzle rows N1 and N2 have overlapping portions in the sub-scanning direction SS when projected in the main scanning direction MS. In this case, the white ink composition and the non-white ink composition are deposited in the same region of the recording medium by the same main scanning of the inkjet head.

[0027] In the above example, the identical area is the part where nozzle row N1, which ejects white ink, and nozzle row N2, which ejects non-white ink, overlap each other in the sub-scanning direction SS when projected in the main scanning direction MS.

[0028] Next, nozzle control of the recording head 2 when the second recording mode is executed will be described with reference to FIG. 3. In the inkjet head shown in FIG. 3, the area is divided into blocks B1 and B2 in the sub-scanning direction SS. In this inkjet head, the type of droplets ejected can be changed for each block and nozzle row. For example, in FIG. 3, the inkjet head may be controlled so that white ink is ejected in block B1 of nozzle row N1, and non-white ink is ejected in block B2 of nozzle row N2.

[0029] In this case, in one main scan, white ink ejected from block B1 of nozzle row N1 is deposited on the recording medium, the recording medium M moves slightly in the sub-scanning direction SS, and in the next main scan, non-white ink ejected from block B2 of nozzle row N2 is deposited on the recording medium so as to be layered on the white ink already deposited. This results in the white ink composition and the non-white ink composition being deposited on the same area of ​​the recording medium by different main scans of the inkjet head.

[0030] In the above example, the identical regions are areas where the white ink composition and the non-white ink composition are deposited in layers by different main scans. As another example of the second recording mode, for example, in the nozzle control of FIG. 2, a white ink composition may be ejected from nozzle row N1, the white ink composition may be ejected and adhered to a recording medium, an ink layer of the white ink composition may be formed, and then the recording medium may be rewound to overlap the ink layer of the white ink composition, and a non-white ink composition may be ejected from nozzle row N2 to eject and adhere the non-white ink composition.

[0031] Note that the nozzle control of the recording head 2 is not limited to the above, and for example, in the embodiment of Fig. 3, the white ink is discharged from the block B1 of the nozzle row N1, and the non-white ink is discharged from the block B1 of the nozzle row N2, so that the white ink composition and the non-white ink composition are deposited on the same area of ​​the recording medium by the same main scan, thereby executing the first recording mode. Also, for example, in the embodiment of Fig. 2, the white ink is discharged from the nozzle row N1 in one main scan, and the recording medium M is not moved in the sub-scanning direction SS, and in the next main scan, the non-white ink discharged from the nozzle row N2 is deposited on the recording medium so as to be layered on the white ink already deposited.

[0032] In FIG. 1, the ink cartridge 3 that supplies a white ink composition and the like to the recording head 2 is composed of four independent cartridges. For example, one of the four cartridges is filled with a white ink composition, and the other cartridges are filled with different types of non-white ink compositions. The ink cartridge 3 is detachably attached to the recording head 2. In the example of FIG. 1, the number of cartridges is four, but this is not limiting and any desired number of cartridges can be installed.

[0033] In addition, a platen 5 is disposed below the recording head 2, and a recording medium M is transported to the platen 5. Furthermore, the recording apparatus 1 may include a heating mechanism 6 that heats the recording medium M. The heating mechanism is one type of drying mechanism.

[0034] The installation position of the heating mechanism 6 is not particularly limited as long as it is provided in a position where it can heat the recording medium M. In the example of Fig. 1, the heating mechanism 6 is installed on the platen 5 at a position facing the recording head 2. When the heating mechanism 6 is installed at a position facing the recording head 2, the position on the recording medium M where the ink or non-white ink composition is attached can be reliably heated, and the white ink composition or non-white ink composition attached to the recording medium M can be efficiently dried.

[0035] Examples of the heating mechanism 6 include a print heater mechanism that heats the recording medium M by contacting it with a heat source, a mechanism that irradiates infrared rays or microwaves, which are electromagnetic waves with a maximum wavelength at around 2450 MHz, a dryer mechanism that blows hot air, and a platen heater.

[0036] The heating mechanism 6 heats the recording medium M before, during, or immediately after the droplets ejected from the nozzles of the recording head 2 adhere to the recording medium M. The control unit CONT controls various heating conditions, such as the timing of heating, the heating temperature, and the heating time.

[0037] 1.2.Carriage The carriage 4 is equipped with a white inkjet head and a non-white inkjet head as the recording head 2, and can detachably mount ink cartridges 3 for supplying each ink composition to the recording head 2.

[0038] The carriage 4 is attached in a state supported by a guide rod 9, which is a support member installed in the main scanning direction, and moves in the main scanning direction along the guide rod 9 by a carriage movement mechanism 7. By ejecting an ink composition from a recording head 2 mounted on the carriage 4 while moving the carriage 4 relative to the recording medium, the ink composition can be deposited on the recording medium M.

[0039] The relative movement of the carriage 4 is not limited as long as it moves the position of either the carriage 4 or the recording medium M relative to the other. Therefore, in the example of Fig. 1, the carriage 4 moves in the main scanning direction, but this is not limited thereto, and it may be a method (lateral scan type) in which main scanning and sub-scanning are performed multiple times by moving the head on a fixed recording medium.

[0040] A carriage movement mechanism 7 moves the carriage 4 in the medium width direction of the recording medium M. A medium feed mechanism 8 transports the recording medium M in a medium feed direction. Here, the medium width direction is the main scanning direction MS, which is the operation direction of the recording head 2. The medium feed direction is the sub-scanning direction SS, which is a direction perpendicular to the main scanning direction MS and in which the recording medium M moves.

[0041] 1.3.Control Unit The control unit CONT can control the overall operation of the printer 1. For example, the control unit CONT can perform control to execute recording by performing main scanning multiple times to eject each ink composition from the recording head 2 and deposit it on the recording medium M while moving the carriage 4 relatively to the recording medium.

[0042] In particular, in this embodiment, the control unit CONT executes a first recording mode in which the white ink composition and the non-white ink composition are deposited onto the same scanning area of ​​the recording medium by the same main scan, and a second recording mode in which the white ink composition and the non-white ink composition are deposited onto the same scanning area of ​​the recording medium by different main scans.

[0043] 1.3.1. First recording mode In the first recording mode, a white ink composition and a non-white ink composition are applied to the same scanning area of ​​the recording medium by the same main scanning to form a layer containing the white ink composition and the non-white ink composition. This makes it possible to improve the recording speed since it is not necessary to stack layers of ink compositions. In addition, when the recording medium is transparent, the image obtained in the first recording mode looks the same when viewed from the front and the back. Therefore, for example, in the case of a recorded material that is used by attaching it to a window or glass, an image that can be seen from both the front and back can be obtained.

[0044] In the first recording mode, the main scan for depositing the white ink composition and the non-white ink composition to the scanning region may be performed multiple times to the same region. That is, it is preferable that after a layer containing the white ink composition and the non-white ink composition is deposited to a certain region on the recording medium by one main scan, a layer containing the white ink composition and the non-white ink composition is further deposited on top of the layer by another main scan. In this case, the main scan for depositing the white ink composition and the non-white ink composition passes multiple times over the same region. The more the number of scans, the more ink can be deposited in a desired region in separate times (multiple passes), and the image quality of the resulting record tends to be improved.

[0045] In addition, when recording an arbitrary area, the number of times the inkjet head passes over the area is also called a "pass". For example, when the main scan is performed four times on the same area to deposit the white ink composition and the non-white ink composition, the number of passes is called 4 passes. For example, in the example of FIG. 2, when the length of one sub-scan in the sub-scan direction is a quarter of the length of the nozzle row N1 in the sub-scan direction, four scans are performed on a rectangular scanning area that is the length of one sub-scan in the sub-scan direction and extends in the main scanning direction. The number of scans viewed in this way is called the number of scans or the number of passes. The number of scans is 1 or more, preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, and particularly preferably 8 or more. There is no upper limit, but it is preferably 24 or less, and more preferably 12 or less. The number of scans is set for each type of ink.

[0046] In the first recording mode, a layer containing the white ink composition may be formed by a main scanning different from the main scanning for forming a layer containing the white ink composition and the non-white ink composition, and a layer containing the white ink composition may be laminated to form a layer containing the white ink composition and the non-white ink composition. In this way, by forming a layer containing a white ink composition, an image with higher color development can be obtained. The formation of the layer containing the white ink composition may be performed before or after the formation of the layer containing the white ink composition and the non-white ink composition. When it is performed before, the image is visually recognized from the recording surface side of the recording medium. When it is performed after, the image is visually recognized from the opposite side to the recording surface side of the recording medium.

[0047] 1.3.2. Second Recording Mode In the second recording mode, a white ink composition and a non-white ink composition are applied to the same scanning area of ​​the recording medium by different main scans to form a layer containing a white ink composition and a layer containing a non-white ink composition by lamination. As a result, the layer containing the white ink composition ensures hiding power, and the color development and visibility of the non-white ink composition formed thereon are further improved, thereby obtaining high-quality image quality.

[0048] In the second recording mode, the order of the white ink composition and the non-white ink composition is not limited as long as they are applied by different main scans. For example, when the white ink composition is applied first and then the non-white ink composition is applied thereon, an image can be formed that can be seen from the ink-applied side. Conversely, when the recording medium is transparent, when the non-white ink composition is applied first and then the white ink composition is applied thereon, an image can be formed that can be seen from the ink-non-applied side.

[0049] In the second recording mode, different main scans for depositing the white ink composition and the non-white ink composition to the same scanning area may each be performed multiple times. For example, it is possible to record the white ink composition in four passes, and then record the non-white ink composition in four passes.

[0050] 1.3.3. Amount of adhesion It is preferable that the control unit CONT controls so that, when a ratio A of the amount of adhesion of the white ink composition to 100% by mass of the non-white ink composition is calculated in an area of ​​the recording medium where the white ink composition and the non-white ink composition are adhered and where the amount of adhesion of the non-white ink composition is the greatest, the ratio A1 in the first recording mode is smaller than the ratio A2 in the second recording mode.

[0051] The ratio of the adhesion amount is expressed as the adhesion amount of the white ink composition / the adhesion amount of the non-white ink composition as a percentage, and if the adhesion amounts of both are equal, it is 100% by mass.

[0052] In the first recording mode, an ink layer mixed with the white ink is formed, so that even if the same amount of the white ink composition is used, the recorded matter is more likely to be white than in the second recording mode. In this respect, by controlling as described above, it is possible to obtain higher quality images in the first recording mode and the second recording mode. Note that the unit area when specifying the adhesion amount is an area having a predetermined area, and can be, for example, an area of ​​2 x 2 mm.

[0053] The ratio A1 in the first recording mode controlled by the control unit CONT is preferably less than 80% by mass, more preferably 5 to 75% by mass, even more preferably 10 to 75% by mass, even more preferably 30 to 70% by mass, and even more preferably 35 to 65% by mass. When the ratio A1 is less than 80% by mass, the color development tends to be improved and the unevenness in shading tends to be reduced. Also, when the ratio A1 is in the above range or more, the visibility tends to be improved.

[0054] Furthermore, in the first recording mode, when the amount of non-white ink composition adhered in the area where the white ink composition and non-white ink composition are adhered and the amount of non-white ink composition adhered is the greatest is defined as the maximum non-white ink adhesion amount B1, it is preferable that the ratio of the adhesion amounts is in the above range over the area where the white ink composition and non-white ink composition are adhered and the area where the amount of non-white ink composition adhered is from the maximum non-white ink adhesion amount B1 to 40 mass % of the maximum non-white ink adhesion amount B.

[0055] Among the regions where the white ink composition and the non-white ink composition are adhered, the region where the amount of adhered non-white ink composition is less than 40 mass% of the maximum amount of adhered non-white ink B1 is a region where the color of the image of the non-white ink composition is relatively light and the difference in image quality is not noticeable to begin with, but in this region, the ratio of the adhered amounts may be within the above range, exceeding the above range, or less than the above range. When priority is given to color development, the ratio may be within the above range or less than the above range. When priority is given to visibility, the ratio may be within the above range or more than the above range.

[0056] The ratio A2 in the second recording mode controlled by the control unit CONT is preferably 80% by mass or more, more preferably 85 to 200% by mass, and even more preferably 90 to 160% by mass. When the ratio A2 is 80% by mass or more, the visibility tends to be improved. Also, when the ratio A2 is 200% by mass or less, the unevenness in the shading tends to be reduced and the adhesion tends to be improved.

[0057] In the second recording mode, when the amount of non-white ink composition adhered in an area of ​​the recording medium where the white ink composition and the non-white ink composition are adhered and the amount of non-white ink composition adhered is the greatest is defined as the maximum non-white ink adhesion amount B2, it is preferable that in areas of the recording medium where the white ink composition and the non-white ink composition are adhered and the amount of non-white ink composition adhered is less than the maximum non-white ink adhesion amount B2, the ratio of the adhesion amounts is within the above range or exceeds the above range, i.e., is equal to or greater than the above range.

[0058] In the second recording mode, even when the ratio of the adhesion amount is high, the visibility and color development tend to be relatively excellent, and even when the adhesion amount range is above the above range, excellent visibility and color development can be obtained.

[0059] In the first recording mode, the maximum deposition amount of the white ink composition in the area where the white ink composition and the non-white ink composition are deposited in an overlapping manner is preferably 10 mg / inch 2 More preferably, it is 8 mg / inch or less. 2 The following is the result.

[0060] The lower limit of the maximum adhesion amount of the white ink composition is preferably 0.50 mg / inch 2 More preferably, it is 1.0 mg / inch or more. 2 More preferably, it is 3.0 mg / inch or more. 2 More preferably, it is 5.0 mg / inch or more. 2 That's all.

[0061] There is no particular restriction on the maximum amount of adhesion of the non-white ink composition, and it may be determined according to the image to be recorded, but it is preferable that the ratio A1 is within the above-mentioned preferred range. This makes it possible to prevent the resulting image from becoming too whitish, and tends to further improve visibility and color development.

[0062] In the second recording mode, the maximum deposition amount of the white ink composition in the area where the white ink composition and the non-white ink composition are deposited in an overlapping manner is preferably 15 mg / inch 2 The maximum deposition amount of the non-white ink composition is preferably within the preferred range in the first recording mode described above, and more preferably within the preferred range in the first recording mode described above.

[0063] The linear encoder 10 detects the position of the carriage 4 in the main scanning direction with a signal. The signal detected by the linear encoder 10 is sent to the control unit CONT as position information. The control unit CONT recognizes the scanning position of the recording head 2 based on the position information from the linear encoder 10, and controls the recording operation, i.e., the ejection operation, of the recording head 2. The control unit CONT is configured to be able to variably control the moving speed of the carriage 4.

[0064] 1.4. Ink composition The white ink composition used in this embodiment contains a white coloring material, and the non-white ink composition contains a non-white coloring material. The white ink composition and the non-white ink composition may each be an aqueous ink composition containing water as the main solvent, or a solvent-based ink composition containing an organic solvent as the main solvent. Below, the components of the ink composition will be illustrated using an aqueous ink composition as an example, but the components constituting the ink composition of this embodiment are not limited to the following.

[0065] The white ink composition and the non-white ink composition used in the present embodiment may be solvent-based inks or water-based inks, but are preferably water-based inks. Water-based inks have high environmental compatibility in that they contain a relatively small amount of organic solvent compared to solvent-based inks. On the other hand, water-based inks tend to be mixed with white inks and non-white inks, which tends to cause a decrease in color development and uneven shading, and in particular, the resulting image tends to be whitish. For this reason, the present invention is particularly useful. Note that when referring to an "water-based" ink, the term "water-based" refers to an ink that contains at least water as a main solvent component. The content of water contained in the ink, etc. is 40% by mass or more, and preferably 50% by mass or more. More preferably, it is 60 to 98% by mass.

[0066] The non-aqueous ink contains an organic solvent as a main solvent component. The content of the organic solvent in the non-aqueous ink is preferably 40% by mass or more, more preferably 50 to 98% by mass. The content of water in the non-aqueous ink is preferably 1% by mass or less, more preferably 0.5% by mass or less. The components of the non-aqueous ink other than the solvent component may be the same as the components that may be contained in the aqueous ink described below.

[0067] In the case of aqueous ink compositions, the white ink composition and the non-white ink composition may contain, in addition to the above-mentioned coloring materials, water, an organic solvent, a surfactant, resin particles, etc. Below, each component of the ink composition will be described in detail using an aqueous ink as an example.

[0068] 1.4.1.White color material The white colorant is not particularly limited, and examples thereof include white inorganic pigments such as CI Pigment White 6, 18, 21, silica, alumina, titanium dioxide, zinc oxide, antimony oxide, magnesium oxide, zirconium oxide, zinc sulfide, barium sulfate, calcium carbonate, etc. In addition to the white inorganic pigments, white organic pigments such as white hollow resin particles and polymer particles can also be used.

[0069] Among the above-listed white coloring materials, it is preferable to use titanium dioxide as the white coloring material, from the viewpoint of good whiteness, etc. The white coloring material may be used alone or in combination of two or more kinds.

[0070] The content of the white coloring material is preferably 1.0% by mass or more, more preferably 3.0% by mass or more, even more preferably 5.0% by mass or more, and particularly preferably 8.0% by mass or more, based on the total amount of the white ink composition. The content of the white coloring material is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 12.5% ​​by mass or less, and particularly preferably 10% by mass or less, based on the total amount of the white ink composition. By having the content of the white coloring material within the above range, it is possible to obtain images of higher quality in the first and second recording modes.

[0071] In the second recording mode, the white ink composition may be used for the purpose of concealing the background of the image. On the other hand, in the first recording mode, the white ink composition is used for the purpose of enhancing the visibility of the image obtained by using it in combination with a non-white ink composition, rather than for the purpose of concealment. Therefore, the content of the white colorant in the white ink composition can be made smaller than when the purpose is to conceal the background. This makes it possible to obtain sufficient visibility of the image, and also makes it easier to improve the dispersion stability of the white colorant and make it less likely to settle. Furthermore, the filling and reduction of image quality differences are also more excellent and preferable.

[0072] The white colorant is preferably capable of being stably dispersed in the dispersion medium, and may be dispersed using a dispersant for this purpose. Examples of dispersants include resin dispersants, and are selected from those that can improve the dispersion stability of the white colorant in the white ink composition containing the white colorant. The white colorant may also be used as a self-dispersing pigment by modifying the surface of the pigment particles by oxidizing or sulfonating the pigment surface with, for example, ozone, hypochlorous acid, fuming sulfuric acid, or the like.

[0073] 1.4.2. Non-white colorants The non-white coloring material is not particularly limited as long as it is a coloring material other than the above-mentioned white coloring materials, but examples thereof include inorganic pigments such as furnace black, lamp black, acetylene black, channel black, and other carbon blacks (CI Pigment Black 7); quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, isoindolinone pigments, azomethine pigments, and organic pigments such as azo pigments. The non-white coloring material may be used alone or in combination of two or more kinds.

[0074] The content of the non-white coloring material is preferably 0.5 to 10 mass %, more preferably 0.5 to 7.5 mass %, and even more preferably 0.5 to 6.0 mass %, relative to the total amount of the non-white ink composition. It is still more preferably 1.0 to 5.0 mass %. By having the content of the non-white coloring material within the above range, color development and visibility are further improved, and higher quality images can be obtained in the first recording mode and the second recording mode.

[0075] It is preferable that the non-white colorant can be stably dispersed in the dispersion medium, and therefore a dispersant may be used for dispersion. Examples of dispersants include resin dispersants, and are selected from those that can improve the dispersion stability of the non-white colorant in the non-white ink composition containing the non-white colorant. In addition, the non-white colorant may be used as a self-dispersing pigment by modifying the surface of the pigment particles by oxidizing or sulfonating the pigment surface with, for example, ozone, hypochlorous acid, fuming sulfuric acid, or the like.

[0076] Examples of non-white ink compositions containing a non-white coloring material include, but are not limited to, cyan ink, yellow ink, magenta ink, and black ink.

[0077] 1.4.3.Water The water content is preferably 45 to 98% by mass, more preferably 55 to 90% by mass, more preferably 60 to 85% by mass, and even more preferably 65 to 80% by mass, based on the total amount of the ink composition.

[0078] Organic Solvents The organic solvent is not particularly limited as long as it is a water-soluble organic solvent, and examples thereof include triol or higher polyols such as glycerin; glycols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, diethylene glycol monoethyl ether, and propylene glycol monoethyl ether. Examples of the organic solvent include glycol ethers such as ethylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and triethylene glycol monobutyl ether; nitrogen-containing solvents such as 2-pyrrolidone, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone; and alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butanol, 2-butanol, tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol. The organic solvent may be used alone or in combination of two or more kinds.

[0079] Glycols are compounds having two hydroxyl groups in the molecule. Examples of glycols include alkanediols in which an alkane is substituted with two hydroxyl groups, and condensates in which the hydroxyl groups of two or more molecules of the alkanediol are condensed together.

[0080] The glycols preferably have 2 to 10 carbon atoms, more preferably 3 to 8 carbon atoms, further preferably 3 to 6 carbon atoms, and particularly preferably 3 to 5 carbon atoms in the molecule.

[0081] The alkanediol is preferably a 1,2-alkanediol or an alkanediol having alkanediol at both ends.

[0082] The nitrogen-containing solvent may be an amide solvent, such as acyclic amides or cyclic amides.

[0083] Examples of the cyclic amides include lactams, such as those mentioned above, pyrrolidones such as 1-propyl-2-pyrrolidone and 1-butyl-2-pyrrolidone, N-methyl-ε-caprolactam, N-cyclohexyl-2-pyrrolidone, β-propiolactam, and the like.

[0084] Examples of the acyclic amides include 3-methoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, 3-methoxy-N,N-methylethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-diethylpropionamide, 3-ethoxy-N,N-methylethylpropionamide, 3-n-butoxy-N,N-dimethylpropionamide, 3-n-butoxy-N,N-diethylpropionamide, 3-n-butoxy-N,N-methylethylpropionamide, 3-n-propoxy-N,N-dimethylpropionamide, 3-n-propoxy-N,N-diethylpropionamide, 3-n-propoxy-N,N-methylethylpropionamide, 3-iso-propoxy- Examples of the alkoxyalkylamides include N,N-dimethylpropionamide, 3-iso-propoxy-N,N-diethylpropionamide, 3-iso-propoxy-N,N-methylethylpropionamide, 3-tert-butoxy-N,N-dimethylpropionamide, 3-tert-butoxy-N,N-diethylpropionamide, and 3-tert-butoxy-N,N-methylethylpropionamide; N,N-dimethylacetoacetamide, N,N-diethylacetoacetamide, N-methylacetoacetamide, N,N-dimethylisobutyric acid amide, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, and N,N-dimethylpropionamide.

[0085] Triol or higher polyols are compounds having three or more hydroxyl groups in the molecule, and examples thereof include glycerin.

[0086] Glycol ethers are compounds in which one or two of the hydroxyl groups of an alkanediol in which an alkane is substituted with two hydroxyl groups or a condensate in which the hydroxyl groups of two or more molecules of the alkanediol are intermolecularly condensed with each other are etherified. The etherification is mono-etherification or di-etherification. The etherification is preferably alkyl-etherification. Glycol ethers are compounds having one or no hydroxyl groups in the molecule. Examples of glycol ethers include those mentioned above.

[0087] Alcohols are compounds in which an alkane is substituted with one hydroxyl group, and have one hydroxyl group in the molecule. Examples of alcohols include those mentioned above.

[0088] Among organic solvents, glycol-based solvents such as propylene glycol, 1,3-propanediol, and 1,2-hexanediol, nitrogen-containing solvents such as 2-pyrrolidone, and glycerin are preferred. By using such organic solvents, the image quality and recording speed of the obtained recorded matter tend to be further improved.

[0089] The content of the organic solvent is preferably 1.0 to 40 mass %, more preferably 3.0 to 30 mass %, even more preferably 5.0 to 15 mass %, and still more preferably 7.5 to 15 mass %, relative to the total amount of the ink composition. The content of the glycol organic solvent may be within the above range.

[0090] The content of the nitrogen-containing solvent is preferably 40% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, and particularly preferably 2% by mass or less, relative to the total amount of the ink composition. The lower limit is 0% by mass or more.

[0091] By setting the content of the organic solvent within the above range, the color development and recording speed of the obtained recorded matter tend to be further improved. When the content of the nitrogen-containing solvent is within the above range, image quality and adhesion are more excellent, which is preferable.

[0092] The normal boiling point of the organic solvent is preferably 150 to 280°C, preferably 160 to 270°C, and preferably 170 to 260°C, more preferably 180 to 200°C, and further preferably 190 to less than 200°C. When the normal boiling point of the organic solvent is within the above range, the adhesion tends to be further improved.

[0093] In particular, the content of organic solvents having a standard boiling point of less than 200° C. among the organic solvents contained in the white ink composition and the non-white ink composition is preferably 50% by mass or more, particularly preferably 55% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more, based on the total amount of organic solvents. The upper limit of the content of organic solvents having a standard boiling point of less than 200° C. is 100% by mass or less, preferably 95% by mass or less, and may be 90% by mass or less. In particular, the content of organic solvents having a standard boiling point of less than 200° C. among the organic solvents contained in the white ink composition is preferably within the above range. By having the content of organic solvents having a standard boiling point of less than 200° C. within the above range, adhesion tends to be further improved. Moreover, the white ink composition and the non-white ink composition preferably contain an organic solvent having a normal boiling point of less than 200°C and an organic solvent having a normal boiling point of 200°C or higher. The organic solvent having a normal boiling point within the above range is preferably a glycol organic solvent.

[0094] The maximum standard boiling point of the organic solvent contained in the white ink composition or non-white ink composition is preferably 280° C. or lower. Furthermore, it is preferably 250° C. or lower, more preferably 240° C. or lower, and even more preferably 230° C. or lower. The maximum standard boiling point of the organic solvent is preferably 150° C. or higher, and more preferably 160° C. or higher. In particular, it is preferable that the maximum standard boiling point of the organic solvent contained in the white ink composition is within the above range. By having the maximum standard boiling point within the above range, adhesion tends to be further improved.

[0095] The weighted average of the standard boiling points of the organic solvents contained in the white ink composition and the non-white ink composition is preferably 290° C. or less, and more preferably 250° C. or less. Furthermore, it is preferably 230° C. or less, more preferably 220° C. or less, even more preferably 210° C. or less, and particularly preferably 200° C. or less. Furthermore, the weighted average of the standard boiling points of the organic solvents is preferably 150° C. or more, and more preferably 160° C. or more. In particular, it is preferable that the weighted average of the standard boiling points of the organic solvents contained in the white ink composition is within the above range. By having the weighted average of the standard boiling points within the above range, adhesion tends to be further improved.

[0096] In particular, it is preferable that the white ink composition and the non-white ink composition are each water-based ink compositions and do not contain more than 2% by mass of organic solvents that are glycols or polyols of triol or higher having a normal boiling point of more than 280° C. "Contains less than 2% by mass" means that alkyl polyol is 0% by mass, or is contained in an amount not exceeding 0% by mass, if any. It is further preferable that the content does not exceed 1% by mass, and more preferably does not exceed 0.5% by mass. The content of the organic solvent having a normal boiling point exceeding 280° C. may be within the above range.

[0097] Surfactants The surfactant is not particularly limited, but examples thereof include acetylene glycol surfactants, fluorine-based surfactants, and silicone-based surfactants. Among these, silicone-based surfactants are preferred. This tends to further suppress unevenness in shading in the resulting recorded matter.

[0098] The acetylene glycol surfactant is not particularly limited, but for example, one or more selected from 2,4,7,9-tetramethyl-5-decyne-4,7-diol, alkylene oxide adducts of 2,4,7,9-tetramethyl-5-decyne-4,7-diol, and alkylene oxide adducts of 2,4-dimethyl-5-decyne-4-ol and alkylene oxide adducts of 2,4-dimethyl-5-decyne-4-ol are preferred.

[0099] The fluorine-based surfactant is not particularly limited, but examples thereof include perfluoroalkyl sulfonate, perfluoroalkyl carboxylate, perfluoroalkyl phosphate, perfluoroalkyl ethylene oxide adduct, perfluoroalkyl betaine, and perfluoroalkyl amine oxide compound.

[0100] Examples of silicone surfactants include polysiloxane compounds and polyether-modified organosiloxanes.

[0101] The content of the surfactant is preferably 0.1 to 4.0% by mass, more preferably 0.3 to 3.0% by mass, and even more preferably 0.5 to 2.0% by mass, relative to the total amount of the ink composition, which tends to further suppress unevenness in shading in the resulting recorded matter.

[0102] 1.4.6.Resin particles By using resin particles, the adhesion of the obtained image is further improved. The resin particles are not particularly limited, but examples thereof include resin particles made of urethane resin, acrylic resin (including styrene-acrylic resin), fluorene resin, polyolefin resin, rosin-modified resin, terpene resin, polyester resin, polyamide resin, epoxy resin, vinyl chloride resin, vinyl chloride-vinyl acetate copolymer, ethylene vinyl acetate resin, etc. The resin particles may be in the form of an emulsion.

[0103] Among these, urethane resins, acrylic resins, and polyolefin resins are preferred. These resin particles are often handled in the form of an emulsion, but may also be in the form of a powder. The resin particles may be used alone or in combination of two or more kinds.

[0104] The urethane resin is a general term for resins having a urethane bond. In addition to the urethane bond, the urethane resin may be a polyether urethane resin having an ether bond in the main chain, a polyester urethane resin having an ester bond in the main chain, or a polycarbonate urethane resin having a carbonate bond in the main chain.

[0105] Acrylic resin is a general term for polymers obtained by polymerizing at least an acrylic monomer such as (meth)acrylic acid or (meth)acrylic acid ester as one component, and examples thereof include resins obtained from acrylic monomers and copolymers of acrylic monomers and other monomers. Examples thereof include acrylic-vinyl resins, which are copolymers of acrylic monomers and vinyl monomers. Examples of vinyl monomers include styrene. Examples of acrylic monomers that can be used include acrylamide and acrylonitrile.

[0106] Among these, styrene-acrylic resins are preferred. The styrene-acrylic resins are not particularly limited, but examples thereof include styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylic acid ester copolymers, styrene-α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid-acrylic acid ester copolymers. By using such resins, the image quality and abrasion resistance of the resulting recorded matter tend to be further improved.

[0107] The polyolefin resin has an olefin such as ethylene, propylene, or butylene in its structural skeleton, and any known polyolefin resin can be appropriately selected and used.

[0108] The content of the resin particles is preferably 0.5 to 15 mass %, more preferably 1.0 to 10 mass %, and more preferably 2.5 to 7.5 mass %, relative to the total amount of the ink composition. When the content of the resin particles is within the above range, the abrasion resistance of the resulting recorded matter tends to be further improved.

[0109] Other Ingredients The ink composition may further contain components such as preservatives, antifungals, rust inhibitors, chelating agents, viscosity adjusters, antioxidants, and antifungal agents, as necessary.

[0110] 1.5. Recording medium The recording medium used in this embodiment is not particularly limited, but examples thereof include absorbent recording media such as paper, film, and cloth, low absorbent recording media such as printed paper, and non-absorbent recording media such as metal, glass, and polymers.

[0111] Among these, from the viewpoint of ink absorption, low-absorbency recording media or non-absorbency recording media are preferred. Also, from the viewpoint of color, non-white recording media are preferred. Conventionally, such recording media have been formed by stacking a white ink layer and a non-white ink layer, and the white ink layer is used as a concealing layer to record high-quality images. Therefore, by using the present invention, the effect of the present invention, that is, an image without unevenness in shading and excellent in color development, can be particularly effectively exhibited.

[0112] In this embodiment, the non-absorbent or low-absorbent recording medium is a recording medium that is absorbent within 30 msec from the start of contact in the Bristow method. 1 / 2 Water absorption up to 10mL / m 2 This refers to a recording medium that is the following: The Bristow method is the most widely used method for measuring the amount of liquid absorbed in a short period of time, and is also adopted by the Japan Pulp and Paper Technical Association (JAPAN TAPPI). Details of the test method are described in Standard No. 51 "Paper and paperboard - Liquid absorbency test method - Bristow method" of the "JAPAN TAPPI Paper and Pulp Test Method 2000 Edition."

[0113] Examples of non-absorbent recording media include those in which a plastic is coated on a substrate such as paper, those in which a plastic film is adhered to a substrate such as paper, plastic films that do not have an absorption layer (receptive layer), etc. Examples of plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc.

[0114] In addition, the low-absorbency recording medium may be, for example, a recording medium having a low-absorbency coating layer on the surface. For example, it may be called coated paper. For example, the substrate may be paper, such as printing paper, coated paper, matte paper, etc., and the substrate may be a plastic film, such as polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc., coated with a polymer or the like, or coated with particles of silica, titanium, etc. together with a binder.

[0115] As the recording medium, an absorbent recording medium can also be used. The absorbent recording medium is a recording medium that is absorbed within 30 msec from the start of contact in the above-mentioned "Bristow method." 1 / 2 Water absorption up to 10mL / m 2 It refers to a "super recording medium."

[0116] Examples of non-white recording media include transparent recording media (transparent recording media). Transparent recording media may be colorless and transparent, or colored (colored) transparent. Transparent also includes semi-transparent. These are recording media that are visually translucent. They are also recording media that are visible light transmissive. In such cases, an image formed on one side of the recording medium by the recording method of this embodiment can be clearly viewed from both sides.

[0117] Further, examples of non-white recording media include non-white colored recording media (non-white colored recording media). Examples include non-white colored opaque recording media and non-white colored transparent recording media. In this case, too, the recording method of this embodiment can easily form an image with good image quality such as visibility, filling, and reduced image quality difference. The non-white colored recording media may be the transparent recording media described above, or may not be transparent recording media. Recording media that are not transparent are recording media that do not have translucency when viewed from the naked eye. Recording media that are not translucent to visible light are also recording media. Here, non-white colored recording media are colors other than white.

[0118] 2. Recording method In the recording method of this embodiment, the recording device is used to select either a first recording mode or a second recording mode, and recording is performed in the selected recording mode.

[0119] The first recording mode or the second recording mode may be selected in advance by a user, and the recording device may execute one of the first recording mode or the second recording mode in accordance with the selection. In this case, the recording mode may be selected on the operation unit of the recording device or on a connection setting screen of a computer that transmits image data to the recording device and instructs recording.

[0120] Alternatively, the control unit of the recording device may select and execute either the first recording mode or the second recording mode depending on the information of the recording medium or the image data to be recorded. When the control unit of the recording device selects between the first recording mode and the second recording mode, the control unit of the recording device may have data that associates the recording medium or the image data to be recorded with the recording mode to be selected, and may select and execute one of the first recording mode and the second recording mode based on such data.

[0121] In the first recording mode, the control unit ejects a white ink composition and a non-white ink composition in the same main scan, deposits them in the same scanned area, and then moves the recording medium in a sub-scan to perform the next main scan.

[0122] In the second recording mode, the control unit ejects either a white ink composition or a non-white ink composition in a certain main scan, deposits it onto a certain scanning region, moves the recording medium by a sub-scan, and ejects the other of the white ink composition or the non-white ink composition in the next main scan, depositing the other ink composition onto the scanning region where one ink composition was deposited in the previous main scan.

[0123] 4 is a flow chart showing an example of the recording control process performed by the recording device used in this embodiment. When starting recording, the control unit of the recording device determines the recording mode in step 400. The recording mode refers to the recording method, recording style, recording aspect, etc.

[0124] The recording mode is determined, for example, by an input signal input to the recording device from an external device such as a computer, or by information input by a user to a user input unit of the recording device. Here, the input signal from the external device or the information input by the user may be information that directly specifies the recording mode, or may be information related to recording, such as a recording speed or image quality. The information related to recording is not limited to these. In the latter case, the recording device stores in advance in the recording device, in a control unit or the like, corresponding information that defines a recording mode corresponding to the information related to recording, and determines the recording mode by referring to the corresponding information.

[0125] In step S401, the determined print mode is identified. In step S402 or S403, the printing device is controlled under printing conditions corresponding to the determined print mode. The printing conditions are, for example, selection of a portion of the nozzle array to be used for printing, which is necessary for printing in the first print mode or the second print mode. In addition, control of the operation of the printing device may also be included. For example, control conditions related to printing, such as the maximum amount of ink deposition and conditions for primary drying, are included.

[0126] In step S404, recording is performed. Although two types of recording modes are shown in the figure, there may be three or more. Control of the recording device may be performed before recording starts as shown in the figure, but it may also be performed during recording. In other words, recording should be performed while the recording device is controlled under the recording conditions.

[0127] In this way, by selecting the first recording mode or the second recording mode depending on the required image quality, recording speed, etc., it is possible to record images with excellent image quality and also at a high recording speed.

[0128] Each recording mode may include a primary drying step. The primary drying step is a step in which the white ink composition or the white ink composition applied to the recording medium is quickly dried by a drying mechanism. In particular, the primary drying step refers to the early drying of the areas to which the white ink composition or the non-white ink composition is applied in the white ink application step and the non-white ink application step.

[0129] The primary drying step is a step of drying the ink attached to the recording medium at an early stage. The primary drying step is a step for drying at least a part of the solvent component of the ink attached to the recording medium to an extent that at least the flow of the ink is reduced. In the primary drying step, the ink composition may be attached to a heated recording medium, or the drying may be performed at a position of the recording medium facing the inkjet head, or the drying may be performed early after the attachment. In the primary drying step, it is preferable that the ink droplets attached to the recording medium start to dry within 0.5 seconds after the attachment of the ink droplets.

[0130] The drying mechanism in the primary drying step is not particularly limited, but examples include a conduction type that uses a platen heater or a preheater for heating, a radiation type that uses an IR heater for heating, and an air blowing type that uses a blower fan. Air blowing removes evaporated solvent components from the media, promoting evaporation and resulting in excellent image quality. The air blowing type is not limited to hot air, and room temperature air may also be used. Room temperature air is also preferable in that it does not have a thermal effect on the nozzle.

[0131] The drying mechanism is also called drying means. The drying means may be used alone or in combination of two or more of these. In particular, it is preferable to use either the conduction type or the radiation type and the blowing type, and it is more preferable to use both the conduction type and the blowing type. In this case, heating is performed by either the conduction type or the radiation type, and evaporation can be promoted by the blowing type, resulting in better image quality. In this case, the blowing type may blow either hot air or room temperature air, but room temperature air is preferred in terms of better ejection stability.

[0132] The surface temperature of the recording medium in the primary drying step is preferably 25° C. or higher, and preferably 60° C. or lower. It is further preferably 30 to 50° C., more preferably 35 to 45° C., and even more preferably 40 to 45° C. Alternatively, it is preferably 30 to 40° C., and more preferably 30 to 35° C. The surface temperature of the recording medium in the primary drying step is the maximum temperature during recording. By keeping the surface temperature of the recording medium in the primary drying step within the above range, the image quality tends to be more excellent.

[0133] Each recording mode may include a secondary drying step. The secondary drying step is carried out after the primary drying step for the purpose of further drying the recorded matter. The secondary drying step refers to drying the recording medium to which the ink composition has been applied sufficiently to enable the recorded matter to be used, and refers to drying carried out to complete the recording. The secondary drying may include heating to turn the components such as the resin contained in the ink composition into a flat film. It is preferable that the heating is started after all the ink that is to be applied to a certain area of ​​the recording medium has been applied, and more than 0.5 seconds after the completion of application.

[0134] The secondary drying step is also called a post-drying step. Heating is preferably used in the secondary drying step. The surface temperature of the recording medium in the secondary drying step is preferably 50 to 120°C, more preferably 50 to 100°C, and even more preferably 60 to 90°C.

[0135] The drying method in the secondary drying method is not particularly limited, but examples thereof include conduction types such as a platen heater and a preheater, radiation types such as an IR heater, and air blowing types such as a blower fan.

[0136] Fig. 5 is a schematic cross-sectional view of the inkjet head and its periphery in the recording device of Fig. 1, as viewed from the side. Fig. 5 also shows a drying mechanism and the like. The recording device 100 includes a carriage 2, an inkjet head 3, a platen 4, a platen heater 4a, a pre-heater 7, an IR heater 8, a blower fan 8a, an after-heater 5, and a cooling fan 5a. Recording is performed on a recording medium 1.

[0137] As a drying mechanism used in the primary drying step, a conduction type using a platen heater 4a or a preheater 7, a radiation type using an IR heater 8, or an air blowing type using an air blowing fan 8a can be used. At least one of these is used to perform the primary drying step. Air blowing by the air blowing fan 8a can promote evaporation by blowing air to the ink adhering to the recording medium in the recording medium near a position facing the inkjet head 4 in the recording medium transport direction. The afterheater 5 is a drying mechanism used in the secondary drying step. EXAMPLES

[0138] The present invention will be described in more detail below using examples and comparative examples, but the present invention is not limited to the following examples.

[0139] 1. Ink Composition Each material was mixed in the composition shown in Table 1 below, and thoroughly stirred to obtain each ink composition. Specifically, each material was mixed uniformly, and insoluble matters were removed using a filter to prepare the ink composition. In Table 1 below, the units of values ​​are mass %, and the total is 100.0 mass %. Unless otherwise specified, the solid content is shown. The colorant was mixed with a dispersant in advance and stirred to prepare a pigment dispersion, which was used in the preparation of the ink. A dispersant resin was used as the dispersant, and a commercially available product suitable for each pigment was mixed in a pigment:dispersant mass ratio of 2:1.

[0140] [Table 1] *The values ​​in parentheses for organic solvents indicate their standard boiling points. Joncryl 537J (acrylic resin particles, manufactured by BASF Japan Ltd.) Silface SAG503A (silicone surfactant, manufactured by Nissin Chemical Industry Co., Ltd.)

[0141] 2. Recording example The recording methods used in the examples are shown in Tables 2 and 3. Table 2 shows the types of white ink compositions and non-white ink compositions used in recording examples A1 to A14 in the first recording mode, as well as recording conditions such as the number of passes, deposition amount, and primary heating temperature. The primary drying temperature refers to the surface temperature of the recording medium when the ink is deposited, heated by the platen heater.

[0142] In the case of Recording Example A14, the number of passes for white only is 3. This is because the white ink composition was first applied alone to the recording medium at a deposition amount of 3 m / inch 2 After that, the recording medium on which the white ink layer was formed was rewound and the white ink layer was placed on top of it, and the color was recorded at 6 mg / inch in six simultaneous passes. 2 and white 3mg / inch 2 The amount of ink adhered is the amount adhered in a 2 x 2 mm area of ​​the recording pattern.

[0143] [Table 2]

[0144] Similarly, Table 3 shows the conditions for Recording Examples B1 to B11 in the second recording mode, and indicates the types of white ink composition and non-white ink composition used, as well as recording conditions such as the number of passes, the amount of adhesion, and the primary heating temperature. In the second recording mode, first, the white ink composition was adhered using the number of passes and amount of adhesion shown in the table, the recording medium on which the white ink layer had been formed was rewound, and the non-white ink composition was applied over the white ink layer using the number of passes and amount of adhesion shown in the table.

[0145] In addition, for reference purposes, a recording example C1 in which recording was performed using only a non-white ink composition, and a recording example C2 in which recording was performed using only a white ink composition were also prepared.

[0146] [Table 3]

[0147] 3. Device example A modified serial inkjet printer (product name SC-S80650) was used as the recording device. The nozzle density per nozzle row was 600 npi, the number of nozzles was 600, and the inkjet head had nozzle rows aligned horizontally in the main scanning direction. The recording resolution was 1200 x 1200 dpi. The number of ink droplets per pixel and the ink amount of the ink droplets were adjusted so that the deposition amount at the resolution was the value shown in the table. The number of ink droplets per pass was also adjusted. The recording device was also equipped with a platen heater and a blowing fan as shown in Figure 4. The wind speed of the blowing fan near the paper surface was 2 m / s, and the air temperature near the paper surface was 25°C. These were set and measured in advance without the influence of the temperature of the platen heater, and recording was performed under these set conditions. The heating strength of the platen heater was adjusted so that the surface temperature of the recording medium became the value shown in the table.

[0148] Then, each ink composition was recorded on a recording medium (PET50A (transparent film), manufactured by Lintec) in a predetermined amount of application and number of passes according to the conditions of each description example, to record a solid image. Thereafter, secondary drying was performed at 70° C. using a secondary drying mechanism, thus obtaining a recorded matter.

[0149] The number of passes shown in Tables 2 and 3 means the number of times the inkjet head passes over a given region when recording that region. For example, if the distance the recording medium is moved by sub-scanning is 1 / 6 the length of the nozzle row in the sub-scanning direction when recording that given region, the inkjet head passes over that region six times, and the ink composition is ejected each time.

[0150] The recording devices were configured so that the control units of the recording devices each executed two recording modes, as shown in Table 4. Each recording device example selected one recording example of each of the two recording modes and executed them in sequence.

[0151] The recording device example in Table 4 is just one example, and the control unit of the recording device may be set to execute any two of the recording examples in Tables 2-3.

[0152] 4. Evaluation 4.1.Recording speed The recording speed was evaluated according to the number of passes required to record on any part of the recording medium, using the following evaluation criteria. (Evaluation Criteria) S: 4 passes or less A: 5 to 7 passes B: 8 to 10 passes C: 11-13 Pass D: 14 ​​passes or more

[0153] 4.2. Visibility The recorded matter obtained as described above was placed on a black paper, and the visibility of the image was visually observed and evaluated according to the following evaluation criteria. Note that if the amount of white ink attached is small, the concealing power of the image is insufficient, and the black of the black paper underneath is visible, making it difficult to see. (Evaluation Criteria) A: It is easy to see. B: Looks slightly black but is easy to see C: Looks black and is difficult to see D: Looks black and difficult to see

[0154] 4.3.Color development The solid image of the recorded matter obtained as described above was measured for OD value under the following measurement conditions using a colorimeter (i1Pro2, manufactured by X-reite), and the color development was evaluated according to the following evaluation criteria. (Measurement conditions) D50 light source, status T, standard observer 2°, background: white paper (Evaluation Criteria) S:OD value is 1.2 or more A: OD value is 1.0 or more and less than 1.2 B: OD value is 0.8 or more and less than 1.0 C: OD value is 0.6 or more and less than 0.8 D:OD value is less than 0.6

[0155] 4.4. Uneven Shading The pattern image of the recorded matter obtained as described above was visually observed, and the density uniformity (unevenness in shading) of the printed matter was evaluated according to the following evaluation criteria. (Evaluation Criteria) S: A uniform image with no unevenness in shading is obtained. A: A good image with no unevenness in shading B: Images without uneven shading are obtained. C: Uneven shading is visible to the naked eye D: There is unevenness in the shade, which is noticeable

[0156] 4.5.Adhesion The recorded matter obtained as described above was rubbed 50 times back and forth with a load of 500 g on a cloth placed on the surface of the coating using a Gakushin type rub fastness tester (manufactured by TESTER SANGYO CO., LTD.). After rubbing, the surface of the coating was visually observed for peeling or scratches, and the adhesion was evaluated according to the following evaluation criteria. (Evaluation Criteria) S: No peeling, almost no fabric transfer A: No peeling, fabric transfer B: Peeling occurred, peeling rate is 10% or less C: Peeling occurred, peeling rate is more than 10% and less than 50% by area D: Peeling occurred, peeling rate exceeds 50%

[0157] [Table 4]

[0158] 5. Evaluation Results From a comparison between the examples and the comparative examples, it was found that all of the examples having the first and second recording modes were able to perform recording with excellent recording speed and excellent image quality. On the other hand, in all of the comparative examples, only recording with excellent recording speed or recording with excellent image quality could be performed. For example, in Example 1, recording with excellent recording speed was achieved by performing the first recording mode, and recording with excellent visibility and color development was achieved by performing the second recording mode. The reference example was provided with only a recording mode in which either the white ink or the non-white ink was used, and it was found that the visibility or color development was inferior. [Explanation of symbols]

[0159] REFERENCE SIGNS LIST 1... printer, 2... recording head, 3... ink cartridge, 4... carriage, 5... platen, 6... heating mechanism, 7... carriage movement mechanism, 8... medium feed mechanism, 9... guide rod, 10... linear encoder, M... recording medium, CONT... control unit

Claims

1. A recording device for recording on a recording medium, The recording medium is a transparent recording medium that is a non-absorbent recording medium, A white ink jet printer that ejects a white ink composition containing a white coloring material and adheres it to the recording medium. Tohead and A non-white ink composition containing a non-white coloring material is ejected and adhered to the recording medium. Jet head and While moving the position of the ink-jet head relative to the recording medium, the ink composition is The composition is discharged from the inkjet head and the main scanning in which the composition is deposited on the recording medium is performed multiple times. and a control unit that controls the recording by The white ink composition and the non-white ink composition are each a water-based ink composition. the law of nature, The control unit: The white ink composition and the non-white ink composition are applied to the recording medium by the same main scanning. The white ink composition and the non-white ink composition are deposited on the same scanned area of ​​the medium. recording in a first recording mode to form a layer containing an ink composition; The white ink composition and the non-white ink composition are applied to the recording medium by different main scanning. The white ink composition and the previous layer are deposited on the same scanned area of ​​the medium. and performing recording in a second recording mode in which a layer containing the non-white ink composition is formed by laminating the non-white ink composition. death, The first recording mode is a recording medium, the white ink composition and the non-white ink composition Among the regions to which the object is attached, in the region to which the amount of the non-white ink composition attached is the largest, The ratio of the amount of the white ink composition attached to 100% by mass of the non-white ink composition attached A recording device, wherein A1 is 10 to 65% by mass.

2. In the area of ​​the recording medium to which the white ink composition and the non-white ink composition are applied, In the region where the amount of the non-white ink composition is the largest, When the ratio A of the adhesion amount of the white ink composition to 100% by mass of the adhesion amount is calculated, The ratio A1 of the first recording mode is smaller than the ratio A2 of the second recording mode. The recording apparatus according to claim 1 .

3. The ratio A1 is 30 to 65 mass%.

3. The recording apparatus according to claim 1 or 2.

4. In the area of ​​the recording medium to which the white ink composition and the non-white ink composition are applied, In the region where the amount of the non-white ink composition adhered is the largest, When the ratio A of the adhesion amount of the white ink composition to 100% by mass of the adhesion amount is calculated, The ratio A2 of the second recording mode is 80% by mass or more. The recording apparatus according to any one of claims 1 to 3.

5. The content of the white coloring material is 8.0% by mass or more with respect to the total amount of the white ink composition. be, The recording apparatus according to any one of claims 1 to 4.

6. the white ink composition contains an organic solvent, The content of the organic solvent having a normal boiling point of less than 200° C. in the organic solvent is the total amount of the organic solvent. is 50% by mass or more, The recording apparatus according to any one of claims 1 to 5.

7. the white ink composition contains an organic solvent, The maximum normal boiling point of the organic solvent is 250° C. or less. The recording apparatus according to any one of claims 1 to 6.

8. the white ink composition contains an organic solvent, The weighted average normal boiling point of the organic solvent is 200° C. or less. The recording apparatus according to any one of claims 1 to 7.

9. In the first recording mode, the white ink composition and the non-white ink composition are The main scanning for depositing the toner on the scanning area is performed a plurality of times on the same area. The recording apparatus according to any one of claims 1 to 8.

10. The first recording mode and the second recording mode are each associated with the inkjet head. The white ink composition and the non-white ink composition are attached to the recording medium at a position on the recording medium facing the recording medium. A primary drying step of drying the ink composition is provided. The recording apparatus according to any one of claims 1 to 9.

11. The recording medium is a plastic film having no absorbing layer. The recording apparatus according to any one of claims 1 to 10.

12. The second recording mode comprises: Among the regions to which the object is attached, in the region to which the amount of the non-white ink composition attached is the largest, The ratio of the amount of the white ink composition attached to 100% by mass of the non-white ink composition attached A2 is 85 to 200% by mass; The recording apparatus according to any one of claims 1 to 11.

13. In the first recording mode, The white ink composition and the non-white ink composition are formed in a layer different from the main scanning. a layer containing the white ink composition is formed by main scanning in the same manner as described above, A layer including the white ink composition and the non-white ink composition, The recording apparatus according to any one of claims 1 to 12, wherein the recording layer is formed by laminating a layer containing the

14. Using the recording device according to any one of claims 1 to 13, Selecting either the first recording mode or the second recording mode, A recording method in which recording is performed in a selected recording mode.

Images