Liquid discharging unit and liquid discharging device

A liquid discharging unit includes a first color nozzle group that includes nozzle arrays each in which nozzle holes for discharging liquids of process colors are arranged in a sub scanning direction perpendicular to a main scanning direction; a second color nozzle group that is provided on upstream side in the sub scanning direction with respect to the first color nozzle group and includes nozzle arrays each in which nozzle holes for discharging liquids of process colors are arranged in the sub scanning direction; and at least one auxiliary nozzle group that is provided between the first color nozzle group and the second color nozzle group and includes nozzle arrays each in which holes for discharging liquids of colors different from the process colors are arranged in the sub scanning direction, wherein the nozzle groups are respectively arranged to be shifted from each other in the main scanning direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2015-239407 filed Dec. 8, 2015. The contents of which are incorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a liquid discharging unit and a liquid discharging device.

2. Description of the Related Art

Conventionally, an inkjet type liquid discharging device is used in a sign graphics field such as indoor and outdoor advertisements, the inkjet type liquid discharging device being provided with inks for background such as a white ink and a metallic ink and inks for image formation of process colors such as black (K), yellow (Y), magenta (M), and cyan (C). The liquid discharging device is capable of first applying an ink for a background such as a white ink over a transparent recording medium surface to obtain a solid print and then printing an image with inks for image formation on the solid print.

Japanese Patent No. 4479224 discloses a technology that includes nozzle groups that discharge an ink for a background on both sides such as an upstream side and a downstream side in a medium conveying direction of nozzle groups that discharge process colors. This arrangement enables execution of white anterior printing in which the background is formed with a white ink prior to an image formed with color inks and of white posterior printing in which an image is formed with color inks prior to the background formed with a white ink, and the like.

However, according to the technology disclosed in Japanese Patent No. 4479224, there is a problem that high density of nozzles causes color bleeding along color boundaries between process colors.

In view of the above conventional problems, there is a need to provide a liquid discharging unit and a liquid discharging device capable of obtaining a simple device in which bleeding along color boundaries is hard to occur and capable of performing white anterior printing, intermediate printing, and white posterior printing.

SUMMARY OF THE INVENTION

According to exemplary embodiments of the present invention, there is provided

Exemplary embodiments of the present invention also provide

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of a liquid discharging unit and a liquid discharging device will be explained in detail below with reference to the accompanying drawings. The embodiments will explain examples in which a recording head is applied as the liquid discharging unit and an inkjet recording device is applied as the liquid discharging device.

First Embodiment

FIG. 1is a schematic diagram illustrating a configuration of an inkjet recording device1according to a first embodiment. The inkjet recording device1which is the liquid discharging device is a serial type inkjet recording device. As illustrated inFIG. 1, the inkjet recording device1includes an image forming unit2that prints a required image, a drying device3, a roll media storage unit4, and a conveying mechanism5. The roll media storage unit4stores roll media (recording media (medium))40. The roll media storage unit4can store recording media40with different sizes in the width direction. The recording medium40is for example a transparent non-permeable medium such as polyethylene terephthalate (PET) film.

The conveying mechanism5constitutes a conveying unit of a roll-to-roll method. The conveying mechanism5has a pair of nip rollers51, a pair of driven rollers52, and a winding roller53, which are provided on a conveying path54of the recording medium40. The nip rollers51are provided in front of the image forming unit2(on the upstream side in a conveying direction A). The nip rollers51convey the recording medium40sandwiched thereby by being rotated with the driving of a motor M (seeFIG. 2) toward the image forming unit2. The winding roller53is rotated with the driving of the motor M to wind up the printed recording medium40. The driven rollers52are rotated with the conveyance of the recording medium40.

The conveying mechanism5includes a wheel encoder55(seeFIG. 2) for detecting a conveying speed. The conveying speed of the conveying mechanism5is controlled by the control of the motor M based on a target value and a speed detected value obtained by sampling detection pulses sent from the wheel encoder55.

In other words, the recording medium40stored in the roll media storage unit4is conveyed to the image forming unit2via the driven rollers52through the rotation of the nip rollers51. The recording medium40having reached the image forming unit2is printed with a required image by the image forming unit2. The recording medium40after being printed is then wound up through the rotation of the winding roller53.

The image forming unit2includes a carriage21. The carriage21is slidably held by guide rods (guide rails)22. The carriage21moves along the guide rods (guide rails)22with the driving of the motor M in a direction (main scanning direction) perpendicular to the conveying direction A of the recording medium40. More specifically, the carriage21reciprocates within a recording area where the image forming unit2can print an image, in a main scanning area which is a movable area in the main scanning direction, with respect to the recording medium40conveyed by the conveying mechanism5.

The carriage21includes a recording head20in which a plurality of nozzle holes each being a discharge opening for discharging a liquid droplet are arranged. The recording head20is integrally provided with a tank for supplying ink to the recording head20. However, the recording head20is not limited to those that are integrally provided with a tank, but may be separately provided with a tank. The recording head20functions as a liquid discharging unit and discharges color ink droplets of black (k), yellow (Y), magenta (M), and cyan (C) which are recording liquids of process colors. The black (k), yellow (Y), magenta (M), and cyan (C) are inks for image formation. In addition, the recording head20discharges an ink droplet of white (W) which is an ink for a background. Moreover, the recording head20discharges color inks of orange (O) and green (G) which are special color recording liquids with a difference in hue from the recording liquids of these process colors, which are used to improve color reproducibility.

The image forming unit2includes a platen23for supporting the recording medium40below the recording head20at the time of printing using the recording head20.

The image forming unit2also includes an encoder sheet for detecting a main scanning position of the carriage21along the main scanning direction of the carriage21. The carriage21includes an encoder26(seeFIG. 2). The image forming unit2is configured so that the encoder26of the carriage21reads the encoder sheet to detect the main scanning position of the carriage21.

The carriage21includes a sensor24that optically detects an edge of the recording medium40according to the movement of the carriage21. The detection signal detected by the sensor24is used to calculate a position of the edge of the recording medium40in the main scanning direction and a width of the recording medium40.

The drying device3includes a preheater30, a platen heater31, a drying heater32, and a warm air fan33. The preheater30, the platen heater31, and the drying heater32are electric heaters using, for example, ceramic or nichrome wire.

The preheater30is provided on the upstream in the conveying direction A of the recording medium40with respect to the image forming unit2. The preheater30preliminarily heats the recording medium40conveyed by the conveying mechanism5.

The platen heater31is disposed on the platen23. The platen heater31heats the recording medium40on which ink droplets discharged from the nozzle holes of the recording head20are caused to land.

The drying heater32is provided on the downstream in the conveying direction A of the recording medium40with respect to the image forming unit2. The drying heater32continuously heats the recording medium40printed by the image forming unit2to facilitate the drying of the ink droplets that land on the recording medium40.

The warm air fan33is provided on the downstream in the conveying direction A of the recording medium40with respect to the drying heater32(image forming unit2). The warm air fan33blows the warm air to the recording surface of the recording medium40on which the ink droplets land. The warm air fan33directly blows the warm air to the ink on the recording surface of the recording medium40to thereby decrease the atmospheric humidity around the recording surface of the recording medium40, and dries the ink completely.

By installing the drying device3, the inkjet recording device1can adopt any non-permeable medium as the recording medium40, such as vinyl chloride, PET, and acryl, which the ink does not permeate. When the non-permeable medium is adopted, the inkjet recording device1can adopt, as inks used for image forming unit2, solvent-based inks excellent in fixing also to the non-permeable medium or water-soluble resin inks containing much resin component.

The inkjet recording device1, configured so that the inks are discharged from the recording head20while the carriage21reciprocates within the width of the recording medium40to form an image, includes unidirectional printing for discharging inks only when a carriage operation is performed only on a forward path to form an image, and bidirectional printing for discharging inks when the carriage operation is performed on both forward and return paths to form an image. The bidirectional printing that is advantageous at a point of a printing speed is mainly used in the inkjet recording device1. Herein, an operation of discharging inks from the recording head20while the carriage21is moving in the main scanning direction is determined as one scan.

A control configuration of the inkjet recording device1will be explained next.FIG. 2is a block diagram illustrating the control configuration of the inkjet recording device1.

As illustrated inFIG. 2, the inkjet recording device1includes a control unit10that controls the entire device. The control unit10includes a central processing unit (CPU)11as a main control unit, a read-only memory (ROM)12, a random access memory (RAM)13, a memory14, and an application specific integrated circuit (ASIC)15. The ROM12stores computer programs executed by the CPU11and other fixed data. The RAM13temporally stores image data and the like. The memory14is a rewritable nonvolatile memory for storing data even when a power supply of the inkjet recording device1is cut off. The ASIC15executes image processing such as various types of signal processing and sorting on image data, and also executes input-output signal processing for controlling the entire device.

As illustrated inFIG. 2, the control unit10includes a host interface (I/F)16, a head drive controller17, a motor controller18, and an input/output (I/O)19.

The host I/F16performs transmission/reception of image data (print data) and a control signal with a host side via a cable or via a network. Examples of the host connected to the inkjet recording device1include, but are not limited to, an information processing device such as a personal computer, an image reading device such as an image scanner, and an imaging device such as a digital camera.

The I/O19receives a detection pulse from the encoder26and the wheel encoder55. In addition, the I/O19connects various sensors25such as a humidity sensor, a temperature sensor, and other sensors to the control unit10, in addition to the sensor24. The I/O19receives a detection signal from the sensor24and the various sensors25.

The head drive controller17controls the drive of the recording head20, and includes a data transfer unit. More specifically, the head drive controller17transfers image data as serial data. The head drive controller17generates a transfer clock and a latch signal, which are required for transfer of image data and confirmation of the transfer or the like, and also generates a drive waveform used when a liquid droplet is discharged from the recording head20. The head drive controller17inputs the generated drive waveform etc. to a drive circuit inside the recording head20.

The motor controller18drives the motor M. More specifically, the motor controller18calculates a control value based on a target value given from the CPU11and a speed detected value obtained by sampling detection pulses sent from the wheel encoder55. The motor controller18drives the motor M based on the calculated control value via an internal motor drive circuit.

The control unit10also includes a heater controller8and a warm air fan controller9.

The heater controller8controls the outputs so that temperatures of the preheater30, the platen heater31, and the drying heater32become set temperatures respectively. More specifically, when controlling the heaters30,31, and32, the heater controller8acquires temperature information using temperature sensors respectively provided in the heaters30,31, and32. The heater controller8then controls so that the temperatures of the heaters30,31, and32become set temperatures respectively while monitoring the temperatures of the heaters30,31, and32. When heaters are provided on the tank and ink routes of the recording head20, the heater controller8also controls the heaters in the above manner.

The warm air fan controller9controls the output of the warm air fan33so that ventilation is performed at a predetermined temperature and air volume.

In addition, the control unit10is connected with an operation panel60for performing an input and a display of information required for the inkjet recording device1.

The control unit10integrally controls the units by the CPU11that loads the computer program read from the ROM12(or memory14) into the RAM13and executes the loaded program. More specifically, the CPU11reads the control contents set in each print mode from the ROM12(or the memory14) based on the print mode set through the operation panel60. The CPU11then controls the units based on the control contents read from the ROM12(or the memory14).

The computer program executed by the inkjet recording device1according to the present embodiment is provided by being recorded in a computer-readable recording medium such as a compact disk read only memory (CD-ROM), a flexible disk (FD), a compact disk recordable (CD-R), and a digital versatile disk (DVD) in an installable or executable file format.

The computer program executed by the inkjet recording device1according to the present embodiment may be configured to be provided by being stored on a computer connected to a network such as the Internet and being downloaded via the network. The computer program executed by the inkjet recording device1according to the present embodiment may also be configured to be provided or distributed via a network such as the Internet.

The computer program executed by the inkjet recording device1according to the present embodiment may be configured to be provided by being preinstalled in a ROM or the like.

Image data transfer/printing processing executed by the control unit10of the inkjet recording device1will be briefly explained next. The CPU11of the control unit10reads and analyses image data (print data) in a reception buffer included in the host I/F16and performs image processing and sorting processing of data required for the ASIC15. Subsequently, the CPU11of the control unit10transfers the image data (print data) processed at the ASIC15from the head drive control unit17to the recording head20.

It may be configured so that dot pattern data for image output is generated by storing font data in, for example, the ROM12or the image data is converted into bitmap data by a host-side printer driver to be transferred to the inkjet recording device1.

Characteristic functions of the inkjet recording device1will be explained next. The inkjet recording device1according to the present embodiment has the following features upon inkjet printing to the recording medium40which is a transparent non-permeable medium.

Essentially, the inkjet recording device1is configured to increase the drying rate of inks by reducing the ink adhesion amount per unit area in one scan. Thus, when color inks are applied to the white ink, the inkjet recording device1can suppress color buried or color mixture, suppress bleeding along a boundary between different colors, and prevent a coating area from being reduced due to its contraction in response to a contact of adjacent droplets with each other between the same colors.

FIG. 3is a plan view illustrating a nozzle configuration of the recording head20, andFIG. 4is a schematic diagram schematically illustrating colors of nozzle arrays.FIG. 3transparently represents the nozzle arrays of the recording head20from above. As illustrated inFIG. 3, the recording head20includes a first nozzle group20abeing a first color nozzle group, a second nozzle group20bbeing an auxiliary nozzle group, and a third nozzle group20cbeing a second color nozzle group.

As illustrated inFIG. 3, the nozzle groups20a,20b, and20care arranged in two lines in the main scanning direction and are alternately arranged in zigzag in the sub-scanning direction. In other words, the nozzle groups20a,20b, and20care arranged in order from the third nozzle group20c, the second nozzle group20b, and the first nozzle group20aso that the nozzle arrays do not overlap each other from the upstream side to the downstream side in the conveying direction A of the recording medium40. In addition, as illustrated inFIG. 3, the second nozzle group20bis disposed by shifting its position from the first nozzle group20aand the third nozzle group20cin the main scanning direction.

Each of the first nozzle group20aand the third nozzle group20cincludes four nozzle arrays that discharge ink droplets of KCMY (process colors) for image formation. Each of the nozzle arrays has 192 nozzle holes from a nozzle hole of nozzle number (No.) 1 to a nozzle hole of nozzle number (No.) 192. In the example illustrated inFIG. 3, for nozzle holes, the nozzle numbers are set in such a manner that the nozzle No. 1 to the nozzle No. 192 are assigned to those from the nozzle hole in the downstream side to the nozzle hole in the upstream side in the conveying direction A of the recording medium40. Each pitch P between the nozzle holes is 150 dots per inch (dpi).

As illustrated inFIG. 4, each of the first nozzle group20aand the third nozzle group20chas a yellow-ink nozzle array NY that discharges an ink droplet of yellow (Y), a magenta-ink nozzle array NM that discharges an ink droplet of magenta (M), a cyan-ink nozzle array NC that discharges an ink droplet of cyan (C), and a nozzle array NK that discharges an ink droplet of black (k).

Similarly to the first nozzle group20a, the second nozzle group20balso includes four nozzle arrays each having 192 nozzle holes from nozzle No. 1 to nozzle No. 192. In the second nozzle group20bsimilar to the first nozzle group20a, the pitch P between the nozzle holes is 150 dpi.

The second nozzle group20bincludes nozzle arrays for auxiliary recording. Specifically, the second nozzle group20bincludes two nozzle arrays that discharge ink droplets of color for background formation and two nozzle arrays that discharge ink droplets of special colors for image formation.

As illustrated inFIG. 4, the second nozzle group20bincludes two nozzle arrays NW that discharge ink droplets of white (W) as an example of an ink for background formation. Moreover, the second nozzle group20bincludes a nozzle array NO that discharges ink droplets of orange (O) and a nozzle array NG that discharges ink droplets of green (G) as an example of special color inks for image formation.

The reason that the nozzle array NW that discharges ink droplets of white (W) is set to two arrays is because the amount of discharge is increased because the white color is frequently used for background formation to cover the whole area.

Thus, the first nozzle group20aand the third nozzle group20cthat discharge ink droplets for image formation and the second nozzle group20bthat discharges ink droplets of the colors for auxiliary recording are arranged in two lines in the main scanning direction, and the second nozzle group20bis disposed in zigzag with respect to the other nozzle groups. Thereby, a plurality of nozzle groups that discharge ink droplets for image formation are provided, and this enables the inkjet recording device1to reduce the ink adhesion amounts of the KCMY (process colors) for image formation per each unit area in one scan and to increase the drying rate of the inks of the KCMY (process colors) for image formation. In other words, by speeding up the drying of the inks of the KCMY (process colors) for image formation, it is possible to suppress bleeding along a boundary between different colors, and to prevent the coating area from being reduced due to its contraction in response to the contact of adjacent droplets with each other between the same colors.

By setting the two arrays in the second nozzle group20bto the nozzle arrays NW that discharge ink droplets of white (W), the inkjet recording device1can reduce an application amount of the white ink in one scan as much as possible, so that the white ink as the background color can be dried until the KCMY (process colors) inks are applied and the color buried and color mixture at the time of applying the KCMY (process colors) inks onto the white ink can be suppressed. If the total application amount is tried to be equal, the number of scans becomes a larger number, but by connecting the nozzle groups to each other in the sub scanning direction instead of the main scanning direction, high quality printing can be achieved without degreasing the productivity.

In the inkjet recording device1, when the recording head20has the nozzle configuration and if the KCMY (process colors) and the white ink are used, the improvement of the productivity can be estimated in all the processes such as the anterior printing, the posterior printing, and the intermediate printing of the white ink.

When the recording head20has the nozzle configuration and if the KCMY (process colors), the special colors, and the white ink are used, the inkjet recording device1evenly uses the nozzle arrays that discharge special color ink droplets and the nozzle arrays that discharge white ink droplets in the second nozzle group20b, thus enabling all the processes such as the anterior printing, the posterior printing, and the intermediate printing of the white ink for the six colors.

The inkjet recording device1can obtain comparatively low nozzle density by arranging the nozzle groups20a,20b, and20cso as to be prolonged in the sub scanning direction even when the white ink is not used. In other words, the ink adhesion amount per unit area in one scan can be reduced, and dots of adjacent droplets are thereby hard to contact each other and bleeding along the color boundary can be suppressed, thus significantly improving the productivity.

Consequently, according to the inkjet recording device1of the first embodiment, it is possible to obtain a simple device in which bleeding along the color boundary is hard to occur and the white anterior printing, the intermediate printing, and the white posterior printing are possible.

In the present embodiment, orange and green are applied as special colors. However, the embodiments are not limited thereto, and therefore special colors of red and blue etc. may be used, or light inks such as light cyan, light magenta, and gray may be used as special colors.

In the present embodiment, the white ink is applied as an auxiliary ink, however, the embodiments are not limited thereto. The inkjet recording device1can apply a silver ink, a gold ink, a transparent ink, a primer, a surface protective agent, etc., as an auxiliary ink. The auxiliary ink is used basically to improve the quality of an image and add some texture thereto by forming an auxiliary layer on the surface or the back of an image layer which is a layer of an image formed with the inks for image formation.

Moreover, in the present embodiment, the black ink is also included in the process colors for image formation, however, it may also be configured not to include the black ink in the process colors for image formation.

Second Embodiment

A second embodiment will be explained next. However, the same reference signs are assigned to the same components as these of the first embodiment, and explanation thereof is therefore omitted.

The second embodiment is different from the first embodiment in an arrangement among the first nozzle group20a, the second nozzle group20b, and the third nozzle group20cin the recording head20.

FIG. 5is a schematic diagram schematically illustrating colors of nozzle arrays according to the second embodiment. As illustrated inFIG. 5, the nozzle groups20a,20b, and20care arranged in three lines in the main scanning direction by being shifted from each other in the sub scanning direction.

Even when the nozzle configuration in the recording head20is as illustrated inFIG. 5, the inkjet recording device1can suppress color buried or color mixture at the time of applying color inks onto the white ink, suppress bleeding along a boundary between different colors, and prevent the coating area from being reduced due to its contraction in response to a contact of adjacent droplets with each other between the same colors.

A comparison result between the inkjet recording device1provided with the recording head20having the nozzle configuration illustrated inFIG. 5and an inkjet recording device with a conventional nozzle configuration will be explained below.FIG. 6is a schematic diagram schematically illustrating colors of nozzle arrays in the conventional recording head. As illustrated inFIG. 6, the conventional recording head is configured so that 12 nozzle arrays of the recording head20are divided by the KCMY (process colors) for image formation, the special colors (O, G), and the white color (W×2).

Upon comparison, when the nozzle density of one nozzle array is 150 dpi and the resolution of a finished image is 900 dpi×900 dpi, a mode that performs 6 scans per nozzle array width is used to print a bleeding check pattern PT illustrated inFIG. 7.

For comparison, it is assumed that “time to wait for drying” such that the carriage21is stopped at a scan edge is provided and the time is converted to the productivity (m2/h).

When the productivity is 40 m2/h, in the printing using the recording head20with the nozzle configuration illustrated inFIG. 5, a satisfactory result with no bleeding (blurring) as illustrated inFIG. 8along all the boundaries between squares can be obtained.

On the other hand, in the printing using the conventional recording head illustrated inFIG. 6, image quality defects such as bleeding (blurring) as illustrated inFIG. 9occur.

The productivity is 20 m2/h when the satisfactory result as illustrated inFIG. 8is obtained by using the conventional recording head illustrated inFIG. 6.

As a result, when the recording head20with the nozzle configuration illustrated inFIG. 5is used, it is understood that the productivity can be twice as much as the case of using the conventional recording head illustrated inFIG. 6.

As for the recording head20with the nozzle configuration illustrated inFIG. 5, in the first nozzle group20aand the third nozzle group20cfor image formation, the order of arranging is K, C, M, and Y, and in the second nozzle group20bfor special colors, the order of arranging is O and G. However, it is desirable that these colors are arranged in the order from the color that comes out good in coloring.

In a permeable paper, the color of an ink that first lands on the paper becomes dominant in coloring, while in the recording medium40which is a transparent non-permeable medium such as a PET film, the color of an ink that lands on the paper later comes out more easily than previous ones when viewed from the surface side. Therefore, for example, when the color of orange (O) is desirably emphasized than black (K) and if the white anterior printing is to be performed on the recording medium40, it is preferable that orange (O) of the second nozzle group20bfor special colors is changed to black (k) and black (k) of the third nozzle group20cis changed to orange (O) in the configuration ofFIG. 5.

Conversely, in the case of white posterior printing, printing is viewed from its reverse surface, and therefore the color of an ink that first lands on the paper becomes strong in coloring. Therefore, it is preferable that black (k) of the first nozzle group20afor image formation is changed to orange (O) and orange (O) of the second nozzle group20bfor special colors is changed to black (k).

In the intermediate printing of the white color, also, by changing black (k) of the first nozzle group20afor image formation to orange (O) and by changing orange (O) of the second nozzle group20bfor special colors to black (k), the color of orange (O) can be enhanced in coloring.

The above has described the nozzle configuration in the case of emphasizing coloring of orange. However, when the entire color gamut is to be enlarged, a single color cannot be emphasized, and therefore it is desirable to compare these cases in various conditions. Especially, in the same nozzle group of the nozzle groups20a,20b, and20c, adjacent droplets contact each other before being dried to cause the colors to mix each other regardless of user's intention, and therefore it is preferable to actually print the image to check how it is like. Thereafter, a nozzle arrangement is preferably selected so that the color gamut becomes largest. The arrangement order of the nozzle arrays in the nozzle groups20a,20b, and20cis preferable that the color gamut of an image to be formed becomes the largest.

Thus, according to the inkjet recording device1of the second embodiment, it is possible to obtain a simple device in which bleeding along the color boundary is hard to occur and the white anterior printing, the intermediate printing, and the white posterior printing are possible.

In the first embodiment and the second embodiment, the configuration, in which the three nozzle groups: the first nozzle group20afor image formation, the second nozzle group20bfor auxiliary recording, and the third nozzle group20cfor image formation are arranged, has been explained as the recording head20, however, the embodiments are not limited thereto.

For example, the recording head20may be those, as illustrated inFIGS. 10 to 12, in which a fourth nozzle group20dbeing an auxiliary nozzle group is disposed in addition to the first nozzle group20afor image formation, the second nozzle group20bfor auxiliary recording, and the third nozzle group20cfor image formation.

According to the examples illustrated inFIGS. 10 to 12, the nozzle groups are arranged in order of the third nozzle group20c, the second nozzle group20b, the fourth nozzle group20d, and the first nozzle group20aso that the nozzle arrays do not overlap each other from the upstream side to the downstream side in the conveying direction A of the recording medium40.

According to exemplary embodiments of the present invention, it is possible to obtain a simple device in which bleeding along the color boundary is hard to occur and the white anterior printing, the intermediate printing, and the white posterior printing are possible.