JP2020131574A - Liquid discharge device, and irradiation control method and irradiation control program for liquid discharge device - Google Patents

Abstract

To provide a liquid discharge device which forms an overcoat layer uniform in glossy feeling without lowering productivity.SOLUTION: A liquid discharge device has a heat unit 300 provided with a plurality of nozzles, discharging an active energy beam curable liquid onto a recording medium, in a moving direction of sub-scanning as a nozzle array, and the head unit and an irradiation part discharge the liquid to the recording medium and irradiate it with light at least in part during a scan movement, the time up to when a nozzle on a rear end side in a moving direction of sub-scanning of the heat unit and irradiation part begins to irradiate the liquid imparted onto the recording medium with light after the liquid is discharged from the plurality of nozzles to the recording medium being longer than the time up to when a nozzle on a front end side in the moving direction begins to irradiate the liquid imparted onto the recording medium with light.SELECTED DRAWING: Figure 9

Description

The present invention relates to a liquid discharge device, an irradiation control method in the liquid discharge device, and an irradiation control program.

After ejecting ink that is cured by active energy rays, the ink is irradiated with active energy rays to form an image. In an active energy ray-curable inkjet printer, clear ink is applied for the purpose of giving gloss to the printed image. There is an active energy ray coating printing technique for overcoating.

In such an active energy ray coating technique, when an overcoat layer is formed on an image, the wet spread of the overcoat layer (gloss layer) differs between the portion where the transparent ink is applied and the portion where the transparent ink is not applied. The gloss of the overcoat layer becomes uneven.

Therefore, in Patent Document 1, in order to make the glossiness of the overcoat layer uniform, the matte layer of the clear coat is applied to a specific area based on the inverted data of the colored ink to wet the overcoat layer. A technique for making the spread uniform has been proposed.

However, in the technique of Patent Document 1, data in which colored ink is inverted is required, and it takes a lot of time to process the data, or after the matte layer, an overcoat layer and two or more jobs are required, and the processing process is required. It will increase and productivity will decrease.

Therefore, in view of the above circumstances, an object of the present invention is to provide a liquid discharge device capable of forming an overcoat layer having a uniform glossiness without lowering productivity.

In order to solve the above problems, in one aspect of the present invention,
A head unit in which a plurality of nozzles for discharging an active energy ray-curable liquid on a recording medium are provided as a nozzle row in the sub-scanning direction, and
An irradiation unit that is connected to the head unit and that irradiates the liquid on the recording medium with light of active energy rays that cures the liquid.
A scanning movement in which the head unit and the irradiation unit are moved in a scanning direction orthogonal to the sub-scanning direction with respect to the recording medium, and the head unit and the irradiation unit are relatively subordinate to the recording medium. A moving unit that alternately performs sub-scanning movements that move in the scanning direction, and
An irradiation control unit that controls lighting and extinguishing by dividing the sub-scanning direction of the irradiation unit is provided.
At least a part of the scanning movement, the head unit and the irradiation unit discharge a liquid to the recording medium to irradiate the recording medium with light.
After discharging the liquid from the plurality of nozzles to the recording medium, the liquid applied to the recording medium by the nozzles on the rear end side in the traveling direction of the sub-scanning direction of the head unit and the irradiation unit is irradiated with light. Provided is a liquid ejection device, which makes the time until the start of irradiating the liquid applied on the recording medium by the nozzle on the tip side in the traveling direction longer than the time until the liquid is started to be irradiated with light.

According to one aspect, in the liquid discharge device, an overcoat layer having a uniform glossiness can be formed without lowering the productivity.

The whole perspective view of the inkjet recording apparatus which concerns on 1st Embodiment of this invention. FIG. 3 is a cross-sectional view of the carriage of FIG. The rear view which shows the arrangement of the head unit and the irradiation unit in the carriage of FIG. The whole view of the inkjet recording apparatus which concerns on 2nd Embodiment of this invention. The block diagram of the hardware composition in an example of the image forming apparatus which concerns on this invention. The functional block diagram of the control part which concerns on image processing of the image forming apparatus which concerns on this invention. FIG. 3 is a diagram illustrating a position of a head and an irradiation state of an irradiation unit in the carriage of FIG. The schematic diagram explaining the position of the scanning area of a head unit with respect to a recording medium in 1st Embodiment. The schematic diagram explaining the state of the dot of each layer for each scan on the recording medium corresponding to the position of the scan area with respect to the recording medium of FIG. 8 in 1st Embodiment. Explanatory drawing of a plurality of types of discharge patterns. It is an enlarged view of the irradiation state of the irradiation part in the carriage of FIG. Control flow of discharge / irradiation adjustment according to the first embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the drawings below, the same components may be designated by the same reference numerals and duplicate description may be omitted.

<First Embodiment>
First, the overall configuration of a plurality of embodiments of the image forming apparatus according to the present invention will be described.

FIG. 1 is a perspective view showing the overall configuration of an inkjet recording device as an image forming device according to the first embodiment of the present invention.

The inkjet recording device 10 includes a carriage 200 and a stage 11 on which a recording medium is placed. The carriage 200 is provided with a head unit 300, which is an inkjet image forming unit including a plurality of liquid discharge heads provided with a plurality of nozzles, and discharges the liquid from the nozzles of the recording head (recording head). Form an image by. The nozzle is provided on the surface facing the stage 11. In the present embodiment, the liquid is, for example, an ink having ultraviolet curability.

Further, an irradiation unit 400, which is a light source for irradiating ultraviolet rays, is provided on the surface of the carriage 200 facing the stage 11. The irradiation unit 400 (an example of the irradiation unit) irradiates light having a wavelength that cures the liquid discharged from the nozzle.

A guide rod 19 is bridged between the left and right side plates 18a and 18b, and the guide rod 19 holds the carriage 200 so as to be movable in the X direction (main scanning direction).

Further, the carriage 200, the guide rod 19, and the side plates 18a and 18b are integrally movable in the Y direction (sub-scanning direction) along the guide rail 29 provided at the lower part of the stage 11. Further, the carriage 200 is held so as to be movable in the Z direction (vertical direction).

In the configuration of FIG. 1, the stage 11 on which the recording medium is placed is fixed. In an inkjet recording device as shown in FIG. 1, a main scanning operation of ejecting ink from a nozzle onto a recording medium while moving the recording head in the main scanning direction and a sub-scanning operation of moving the recording head in the sub-scanning direction are alternated. Repeatedly to form an image.

Therefore, in the present embodiment, the carriage 200 and the guide rod 19 are moving portions in the main scanning direction (X direction, second direction), and the carriage 200 and the guide rail 29 are in the sub scanning direction (Y direction, first direction). ) Functions as a moving part.

Next, the details of the carriage (main scanning unit) 100 will be described with reference to FIGS. 2 and 3. A detailed cross-sectional view of the carriage 200 is shown in FIG. 2, and a rear view is shown in FIG. The central head unit 300 provided on the carriage 200 discharges ink. The head unit 300 includes heads (colored heads) 301CM and 301YK that eject CMYK color inks, respectively.

Each head 301 is formed with four rows of nozzle rows having a plurality of nozzle holes for ejecting ink in the sub-scanning direction, and the CM head 301 is filled with two rows of C and M ink. The YK head 301 is filled with Y and K ink in two rows each. Further, there is also a 301S that ejects S ink, which is a special color ink that is a specific color (spot color) such as a specific color that is frequently used or a special color that cannot be created by mixing YMCK or the like.

The head unit 300 is also provided with 301CL1 and CL2 that eject clear ink (transparent ink) that forms a gloss coat layer. In this configuration, the head on the upper right side of the head unit does not discharge clear ink, but discharges, for example, a primer (Pr) which is a base and a second special color. Each color head is provided with a three-row head in the sub-scanning direction, and the head that ejects clear ink is a two-row head.

Each head 301 is an example of a liquid ejection head in which ink is ejected by causing a contraction motion of the piezo when a drive signal is applied to the piezo and a pressure change due to the contraction motion.

In order to maintain and recover the performance of the head 301, the carriage 200 is moved to the maintenance unit 500 shown in FIG. 1, and the head is maintained. Although not shown, the carriage 200 is provided with a pressurizing mechanism. The pressurizing mechanism ejects an arbitrary amount of ink from the head. When the ink is discharged, ink may remain on the surface of the nozzle surface of the head 301. Therefore, the wiper 501 rises and moves in the sub-scanning direction to wipe off the ink adhering to the surface of the head 301. To do.
The carriage 200 includes a height sensor 41. The height of the recording medium 101 is measured by the height sensor 41. From the measured value, the carriage 200 descends to a position where the gap between the heads of the head 301 and the recording medium 101 is 1 mm or an arbitrary set value.

In image formation, when the carriage 200 reciprocates (passes) on the recording medium 101 in the main scanning direction (X direction), ink is ejected from the head 301 of the head unit 300 to form an image. During the reciprocating motion of the carriage 200, the ink ejected from the head 301 onto the recording medium 101 is cured by UV light (ultraviolet) which is an active energy ray emitted from the irradiation unit 400.

Then, at each end of scanning, the carriage 200 moves to a predetermined position in the sub-scanning direction, and an image is formed on the surface of the recording medium 101.

When obtaining a clear gloss coating, instead of irradiating the ink immediately after ejection, after applying the clear ink to the required part, the ink is cured at a predetermined timing after a predetermined time elapses to form a gloss coating layer. To do. After applying the clear ink, the time for the clear ink to smooth (hereinafter referred to as the leveling time) is adjusted and set. The setting of the leveling time from the application of the clear ink to the irradiation of UV light will be described in detail together with FIGS. 7 to 12.
In addition to the gloss coating, the coating described here may be a color ink or a clear ink directly applied to the entire surface of the base material, or a clear ink may be applied after printing the color ink.

As shown in FIG. 3, the irradiation unit 400 is composed of an aggregate of a plurality of LED-UV lamps using LEDs as a light source, and is provided with irradiation units 400L and 400R on the left and right sides, respectively. The lamp groups 401L and 401R are divided into irradiation blocks 401L1 to L9 and 401R1 to R9 composed of independent lamps, and each irradiation block can independently control the LED output.

The lamp groups 401L and 401R are connected to the lamp moving mechanism 42. The lamp moving mechanism 42 is connected to a lamp fixing mechanism 43 fixed to the head unit 300 of the carriage 200 and a guide rail 444. The lamp fixing pin 45 is connected to the lamp fixing mechanism 43 through the lamp moving mechanism 42. By turning the lamp fixing pin 45 to release the fixing and pushing and pulling the lamp group 401, the lamp group 401 can move in the sub-scanning direction along the guide rail 44. When the lamp group 401 moves to an arbitrary position, it can be fixed by the lamp fixing pin 45 and printing can be performed at the arbitrary lamp position.

<Second Embodiment>
FIG. 4 is an overall view (rear view) of the inkjet recording device according to the second embodiment of the present invention.

In the present embodiment, the transport belt 71, which is a transport means on which the recording medium 101 is placed, is movable. In the inkjet recording device 1 of the present embodiment, in the sub-scanning operation, the recording medium 101 is moved in the sub-scanning direction with respect to the carriage 20 including the head unit 30 and the irradiation units 40L and 40R.

In the present embodiment, a transport belt 71 for transporting the recording medium 101, transport rollers 72a and 72b are provided, and a suction support plate 72 for maintaining the transport state is provided. Further, maintenance units 50a and 50b are provided on both sides of the transport belt 71 in the scanning direction.

Therefore, in the present embodiment, the main scanning operation of ejecting ink onto the recording medium from the nozzles of the plurality of heads 301 while moving the carriage 20 in the main scanning direction and the sub-scanning operation of moving the recording medium 101 in the sub-scanning direction. And are repeated alternately to form an image.

Therefore, in the present embodiment, the carriage 20 and the guide rod 19 are moving portions in the main scanning direction (X direction, second direction), and the transport belt 71, the suction support plate 72, and the transport rollers 72a and 72b are in the sub-scanning direction. It functions as a moving part (Y direction, first direction).

<Hardware configuration example>
FIG. 5 is a block diagram showing an example of the overall configuration of the hardware configuration of the image forming system including the inkjet recording devices 10 and 1 of any of the first and second embodiments. In the system shown in FIG. 5, in the image forming system, as shown in FIGS. An example is shown in which PC2, which is a device, is connected and PC2 executes image processing. The function related to the image processing executed by the PC 2 may be provided inside the image forming apparatus.

The PC2 (computer) 2 is equipped with a printer driver. The printer driver changes the image data into recorded data. The recorded data converted by the printer driver is transmitted to the inkjet recording device 10. The recorded data includes command data for operating the transport unit 600 and the like, and pixel data related to the image. Pixel data is composed of 2-bit data for each pixel and is represented by 4 gradations.

As shown in FIG. 7, the image forming apparatus 30 (invertical recording apparatus 10, 1) of the present embodiment includes a controller unit 3, a detection group 4, a transport unit 600 as a transport unit, a carriage 200, and a head unit. It includes 300, an irradiation unit 400, and a maintenance unit 500.

Further, the controller unit 3 includes a unit control circuit 31, a memory 32, a CPU (Central Processing Unit) 33, and an I / F 34. The controller unit 3 controls each unit from the data received from the PC 2 which is a computer to form an image. The controller unit 3 is also a computer that controls each unit based on the detection data of the detection group 4.

The I / F 34 is an interface for connecting the image forming apparatus 30 (10, 1) to an external PC (Personal Computer) 2. The connection form between the image forming apparatus 30 and the PC 2 may be any form, and examples thereof include a connection via a network and a form in which both are directly connected by a communication cable.

Examples of the detection group 4 include various sensors provided in the inkjet recording device 10 (1) such as the height sensor 41 shown in FIGS. 2 and 3.

The CPU 33 uses the memory 32 as a work area to control the operation of each unit of the inkjet recording device 10 via the unit control circuit 31. Specifically, the CPU 33 controls the operation of each unit based on the recorded data received from the PC 2 and the data detected by the detection group 4, and is a liquid coating surface 102 on the recording medium 101 (base material). Form an image.

(Functional block)
Next, the functional block of the present invention will be described. FIG. 6 is a functional block diagram relating to image processing in the image forming system according to the present invention.

The image processing device 12 includes a main control unit 13. The main control unit 13 is a computer including a CPU and the like, and controls the entire image processing device 12. The main control unit 13 may be configured by a CPU other than a general-purpose CPU. For example, the main control unit 13 may be configured by a circuit or the like.

Further, as shown in FIG. 6, the image processing device 12 may be realized by a PC 2 connected to the image forming device 30, or may be provided inside the image forming device 30.

The main control unit 13 includes a data receiving unit 12A, a data creating unit 12B, and a data output unit 12C. A part or all of the data receiving unit 12A, the data creating unit 12B, and the data output unit 12C may be realized by, for example, a processing device such as a CPU, that is, software, or an IC (Integrated). It may be realized by hardware such as Circuit), or it may be realized by using software and hardware together.

The data receiving unit 12A receives the image data. The image data is information such as the shape and color of the image to be formed. The data receiving unit 12A may acquire image data from an external device via a communication unit, or may acquire image data from a storage means provided in the image processing device 12.

The data creation unit 12B performs predetermined data processing such as mask processing on the image data received by the data receiving unit 12A. In the present embodiment, image data (for example, JPEG image data), color ink image data, and image data for clear ink are created based on a desired glossiness.

The data output unit 12C outputs the image data created by the data creation unit 12B to the image forming apparatus 30.

The image forming apparatus 30 (10, 1) includes a recording drive unit 26, a print mode receiving unit 21, an irradiation unit 22, drive units 23 and 24, a recording control unit 27, and an irradiation control unit 28. ..

The recording drive unit 26 is a head drive unit that drives the droplet ejection of the head units 300K to 300W based on the image data controlled by the recording control unit 27.

The irradiation unit 22 corresponds to the lamp groups 401R and 401L that are the light sources in the irradiation units 400R and 400L provided on the carriage 200, and each block that is one or a plurality of lamps that divide the lamp group 401R and 401L sub-scanning directions. It is an irradiation drive unit that drives ON / OFF of the carriage.

The drive units 23 and 24 drive the moving unit, the first driving unit 23 drives the movement (scanning movement) of the carriage 200 in the X direction during scanning, and the second driving unit 24 drives the moving unit. , The movement (sub-scanning movement) of the carriage 200 (first embodiment) or the recording medium 101 (second embodiment) in the sub-scanning direction during the sub-scanning is driven.

The recording control unit 27 receives print data from the image processing device 12. The recording control unit 27 controls the recording drive unit 26 so as to eject the droplets corresponding to each pixel from the head 18 according to the received print data.

Further, the recording control unit 27 calculates, for example, the time from ink ejection to light irradiation, and the calculation of the glossiness of the image formed on the recording medium 101 from the ink ejection amount and the time until light irradiation. , Perform calculations to determine the discharge rate of colored ink and clear ink to make the glossiness uniform.

The irradiation control unit 28 controls the irradiation unit 22 so as to set the irradiation timing and irradiation time of each block of the irradiation unit in response to the instructions of the mat area (mat unit) and the gloss area (gloss unit).

Specifically, the recording control unit 27 includes a gradation setting unit 27A for colored ink, a transparent ink ejection pattern selection unit 27B, a gradation setting unit 27C for transparent ink, a printing rate adjustment unit 27D, and a drop size adjustment unit 27E. ing.

The gradation setting unit 27A for colored ink is set so that a gradation mask is applied to each head of the image data formed in color so that both ends of the head of the colored ink in the sub-scanning direction gradually become thinner.

The transparent ink ejection pattern selection unit 27B selects which method of the transparent ink gradation setting unit 27C, the printing rate adjustment unit 27D, or the drop size adjustment unit 27E is used to separately paint the matte area and the gloss area with the transparent ink. To do. The details of the painting method will be described later together with FIG.

The transparent ink ejection pattern selection unit 27B, the transparent ink gradation setting unit 27C, the printing rate adjusting unit 27D, and the drop size adjusting unit 27E function as a liquid ejection amount adjusting unit 270 for adjusting the ejection amount of the transparent ink.

The irradiation control unit 28 includes an irradiation area setting unit 28A and an irradiation time setting unit 28B.

The irradiation area setting unit 28A sets an area to be irradiated in the irradiation unit 22. The irradiation time setting unit 28B sets the irradiation start timing and irradiation time of the lamp in the irradiation unit 22. The detailed control of the lamp group (irradiation unit) 401L and 401R will be described in detail together with FIG.

In this block diagram, an example having a function of adjusting the ejection of transparent ink and adjusting the irradiation portion on the image forming apparatus side has been described, but the function of adjusting the ejection of transparent ink and the irradiation portion is on the PC2 side. It may be provided in the data creation unit 12B of.

Further, in another information processing device (for example, a higher-level device) connected to the PC2, a program is set in advance and stored in a calculation file (for example, a CSV (Comma Separated Value) file or an Excel file) format, and the PC2 By reading the program in, the clear ink ejection adjustment program may be executed.

<Example of adjusting irradiation and discharge pattern>
Next, the adjustment of discharge and irradiation in the first embodiment will be described with reference to FIGS. 7 to 12. FIG. 7 is a diagram for explaining the position of the head and the irradiation state of the lamp group 401R in the head unit 300 of the carriage 200 of FIG. As shown in FIG. 7, the head unit 300 is provided with two heads 301CL1 and 301CL2 for ejecting UV curable clear ink in the sub-scanning direction.

As shown in FIG. 7, color is printed by the four colored heads 301C1, M1, Y1 and K1 on the most advanced side, and clear coating is applied on the colors by the clear heads 301CL1 and CL2.

In the same scanning movement operation, if the clear ink is ejected immediately after the colored ink is ejected, the colored ink and the color ink are mixed and the target image cannot be formed. Therefore, in the same scanning operation, the same position in the sub-scanning direction. Colored ink and clear ink are not ejected from the head.

The head on the front end side and the head on the rear end side, which will be described below, are the front end side (front side) and the rear end side in the traveling direction (moving direction) in the sub-scanning direction of the carriage in a plurality of heads for discharging clear ink. Means (back side).

The irradiation unit 400 is configured by arranging a plurality of lamps each having an irradiation area divided in the sub-scanning direction, and the plurality of lamps can be individually turned on and off. The lamp irradiates light of active energy rays that cure the ink and cure the liquid.

In FIG. 7, the irradiation unit 400 shows a state during the discharge operation. The lamps 401R5 to R8 are turned off, and the lamps 401R1 to R4 and 401R9 are turned on. That is, the portion corresponding to the clear head 301CL2 on the rear end side is turned off, and at least a part of the portion corresponding to the clear head 301CL1 on the front end side is turned on.

In this way, a part of the tip side of the tip side head 301CL1 is irradiated by the lighting portion (401R3, R4) of the lamp, so that at least a part of the ink discharged from the tip side head 301CL1 is discharged after the discharge. Immediately cure to matte (becomes a matte area).

Therefore, a part of the rear end side head 301CL2 and the front end side head 301CL1 is located at the non-lighting portion (401R5, R6, R7, R8) of the lamp, and the ink discharged from the rear end side head is , It is not irradiated immediately after ejection, but after leveling, it is irradiated at the lighting part of the lamp and becomes gloss (becomes a gloss area).

In this example, there are two examples of clear heads that eject clear ink, and the region ejected from a part of the nozzles on the tip side of the front end side head is set as a matte area, and the rear end side head The area discharged from the remaining nozzles on the rear end side of the front end side head is set as the matte area, but the area allocation may be another setting.

Here, assuming that the entire sub-scanning area of one or a plurality of clear heads that eject clear ink is "plurality of nozzles", the nozzle that ejects clear ink that becomes a matte region is the "tip side nozzle" in the traveling direction. , The nozzle that ejects the clear ink that becomes the gloss region can be considered as the "nozzle on the rear end side".

In the example of FIG. 7, the “tip side nozzle” corresponds to a part of the tip side nozzles of the front end side head, and the “rear end side nozzle” is the rear end side of the rear end side head and the front end side head. Corresponds to the remaining nozzles of.

Further, when the lengths of the head and the lamp in the sub-scanning direction can be made substantially equal, the "tip side nozzle" corresponds to the nozzle of the entire front end side head, and the "rear end side nozzle" is the rear end side. Corresponds to the nozzle in the entire head of.

Further, the number of clear heads for discharging clear ink can be three or more, or one. For example, when the matte area and the gloss area are set by using one clear head, the "tip side nozzle" corresponds to a part of the nozzles on the tip side in the traveling direction in one head, and the "rear end". The "side nozzle" corresponds to the nozzle of the remaining portion on the rear end side in the traveling direction in one head.

<State of ink droplets>
Here, with reference to FIGS. 8 and 9, the ink landing area by a plurality of scans and the state of the landing droplets when the lighting unit shown in FIG. 7 is controlled to turn on / off will be described.

FIG. 8 is a schematic diagram illustrating the position of the scanning area of the head unit with respect to the recording medium in the first embodiment. FIG. 9 is a schematic diagram illustrating the state of landing droplets of each layer for each scan on the recording medium, which corresponds to the position of the scanning area with respect to the recording medium of FIG. 8 in the first embodiment.

In FIGS. 8 (a), 8 (b), 8 (c), and 8 (d), the position of the recording medium 101 is fixed, and the carriage 200 is moved by the line feed width in the sub-scanning direction. It is a figure which shows the position of the scanning area of the 1st scan, the 2nd scan, the 3rd scan, and the 4th scan.

FIG. 8 describes a bidirectional printing sequence in which an image is formed on a recording medium by alternately repeating an operation in which the carriage scans in the main scanning direction and an operation in which the carriage moves in the sub-scanning direction. The operation of moving the carriage in the sub-scanning direction during the reciprocating operation of the carriage in the main scanning direction is also referred to as a movement operation corresponding to the line feed width.

In this example, an example of the line feed width in the sub-scanning direction = the width of the gloss area is shown.

In FIGS. 9 (a), 9 (b), 9 (c), and 9 (d), FIGS. 8 (a), 8 (b), 8 (c), and 8 (d), respectively. It is a schematic diagram which shows the state of the dot (ink drop) which landed by the 1st time, the 2nd time, the 3rd time, and the 4th time of scanning shown in 1. Note that FIG. 9 corresponds to a view viewed from the right side of FIG.

Here, as shown in FIGS. 9 (a) to 9 (d), during printing, the lamps 401R1, R2, R3, R4, R5 and R9 are always ON in the irradiation unit 400 as shown in FIG. Lamps 401 R6, R7, R8 are always set to OFF.

As shown in FIGS. 8A and 9A, only colored ink droplets are ejected in the first scan. Then, the colored ink droplets are irradiated by the lamp on the tip side, and the colored ink droplets are cured.

As shown in FIGS. 8 (b) and 9 (b), colored ink droplets are ejected in the second scan, and clear ink droplets are ejected from the clear head on the tip side. Then, the colored ink droplets and the clear ink are irradiated by the lamp on the tip side, the colored ink droplets are cured, and the clear ink droplets become matte.

Here, in the ejection region of the clear ink tip side head 301CL1, the time from the ink droplet landing on the recording medium 101 (base material) to the UV irradiation is performed by irradiating the light with the same scanning as the ink application. short. As a result, the landing droplets are hardened with almost no leveling (unification, smoothing) between the landing droplets while standing, and as a result, unevenness is formed on the surface, giving a matte feeling as an image quality. It can be a matte area.

As shown in FIGS. 8 (c) and 9 (c), in the third scan, colored ink droplets are ejected, and clear ink droplets are ejected from the clear heads CL1 and CL2 on the front end side and the rear end side. Then, the tip-side lamp irradiates the tip-side region of the colored ink droplets and the clear ink droplets, the colored ink droplets are cured, and the clear ink droplets become matte. The area of the clear ink droplets ejected by the head on the rear end side is not irradiated with light and does not cure in this same scan.

As shown in FIGS. 8 (d) and 9 (d), in the fourth scan, colored ink droplets are ejected, and clear ink droplets are ejected from the clear heads CL1 and CL2 on the front end side and the rear end side. Then, the lamp on the tip side irradiates the colored ink droplets and a part of the clear ink droplets ejected from the head 301CL1 on the tip side on the tip side to cure and form a mat. The clear ink droplets applied from the head on the rear end side are not irradiated with light and do not cure in this same scan. Further, the clear ink droplets ejected last time are irradiated with light from the lamp 401R9 on the rear end side.

As shown in FIGS. 9 (c) and 9 (d), the clear ink droplets applied to the recording medium by the head 301CL2 on the rear end side are not immediately irradiated with light by the lamp 401. Light is emitted from the corresponding block after a lapse of time for one scan.

In the region where the clear ink is applied by the head on the rear end side, the time from the ink droplet landing on the recording medium (base material) to the UV irradiation becomes longer, so that the dots become wet and spread, and the leveling progresses. The dot height becomes lower. When UV light is irradiated in a state where this leveling is advanced, it becomes a gloss region that gives a glossy feeling to the image surface and gives a glossy feeling.

In FIG. 9D, the clear ink droplets on the third layer enter the gaps between the ink droplets on the matte region of the second layer having irregularities.

Further, the clear ink droplets ejected from the head on the rear end side, which were not irradiated with light in the third scan of FIG. 9 (c), were subjected to UV in the fourth scan of FIG. 9 (d). Light is emitted. Therefore, for at least one scan, the ink droplets in that area are left as the time before the lamp irradiation, so that the second layer of landing droplets are formed in the concave portion of the first layer having irregularities cured in a standing state. By entering, the surface is further smoothed (leveled).

In the example of FIG. 9, since the clear ink is not ejected at the first scan on the rear end side when the printing operation is started during the printing operation, the formation of the matte layer by the clear ink is realized after the second scanning. Further, at the start of the printing operation, the liquid is discharged from the rear end side head for the first time in the third scan, and the region becomes a gloss region by being irradiated with light from the next scan (fourth scan) onward.

The head unit is provided with y heads in the sub-scanning direction, of which at least two are clear heads. Therefore, from the front end side (y-1st) is the clear ink head on the front end side, and the yth is the clear ink head on the rear end side. Therefore, the formation of the matte layer by the clear ink ejected from the front end side head is realized after (y-1) scans, and the formation of the gloss layer by the clear ink ejected from the rear end side head is (y + 1). ) Realized after the second scan.

Further, as shown in FIGS. 9 (a) to 9 (d), as the carriage moves in the traveling direction due to a line break, ink droplets are ejected to the tip side (right side in FIG. 9) in the traveling direction. As shown in FIG. 9D, the gloss region is formed on the rear end side (left side) of the region where the ink droplets have landed on the medium, which is the rear end side of the ink droplet forming region. Therefore, ink droplets are not superimposed on the gloss layer.

In this way, by providing a plurality of heads for ejecting clear ink in the sub-scanning direction and making the irradiation start timing different from that of the head on the rear end side of the tip side in the traveling direction of the carriage in the sub-scanning direction, at least the fourth time. After the scanning of, a gloss layer is formed on the matte layer for each line feed width, so that the uppermost layer on the rear end side is always a gloss layer. Since the matte layer is always formed, the matte layer reduces the unevenness even in a portion having severe irregularities such as a thin portion of the color layer, so that the gloss layer can be easily wetted and spread. Therefore, it is possible to form an overcoat layer having a uniform glossiness without creating special discharge data.

Note that FIG. 9 illustrates an example in which a gloss layer is formed by irradiating the ejection region (scanning region) of the rear end side head in the previous scanning in the next scanning of the scanning in which the clear ink is ejected. However, a gloss layer may be formed by irradiating light in a scan after the next scan in which the clear ink is ejected.

In that case, the irradiation area protruding toward the rear end side from the area where the liquid is discharged by the discharge head is further moved to the rear end side, or the line feed amount is reduced to increase the number of scans. As a result, after scanning at least two times later, the clear ink ejection region of the rear end head is irradiated with light, so that the time until irradiation becomes longer and the gloss becomes more advanced in leveling.

Utilizing the mechanism of FIG. 9, the head on the rear end side in the sub-scanning direction is irradiated with light one or more times after the ink is ejected to make the surface glossy. Returning to FIG. 7, since the ink ejected from the nozzles corresponding to the extinguished portions of the lamps 401R6 to R8 is not cured immediately, the ink is leveled (smoothed) and then the lamps 401R9 irradiate to form a coating film.

As described above, in the present invention, by adjusting the illumination start timing (leveling time), the front end side is set to the matte region and the rear end side is set to the gloss region (overcoat layer), so that the clear ink is applied with a time lag. The additional operation of discharging is not required, and the mat and the gloss overcoat layer can be formed by a series of operations.

Further, it is more preferable to adjust the amount of clear ink adhered between the matte region and the gloss region together with the adjustment of the irradiation start timing.

As a premise, in a color image formed by a colored head that is ejected before clear ink, banding is easy to see due to line feed error, etc., so the printing rate at the edge of the ejected ink is reduced to visually recognize the banding. It is difficult to do.

When ejecting clear ink, the masks used in the matte area and the gloss area are different, and a gradation mask is used for the matte area and a uniform mask is used for the gloss area.

Specifically, in the tip side head 301CL1 of the clear head, it is preferable to set the adjustment discharge pattern so that the amount of liquid applied at both ends in the sub-scanning direction is smaller than that at the center. Even in the matte area formed by the clear head, banding becomes more noticeable due to line feed error and the like as in the case of color, so that the printing rate at the edge is low as in the case of color.

On the other hand, the head 301CL2 on the rear end side of the clear head adjusts the discharge amount of clear ink so that the liquid is uniformly discharged. Even in the gloss region, if the ink droplets are ejected with a large dot interval such as a gradation, it becomes difficult for the ink droplets to coalesce and the wet spread becomes poor, so the gradation is not used. Further, in the gloss region, since the ink droplets get wet and spread and become smooth, there is no banding due to feeding or the like, so there is no need to make a gradation.

Specifically, in FIG. 7, the colored heads 301C1, M1, Y1, K1 and the clear head CL1 which is the tip side head in the clear ink ejection region have a gradation-like imparting amount having a low edge imparting amount (printing rate). The clear head CL2 has a substantially uniform printing rate.

Of R3 to R5 of the lamp 401, which corresponds to the ejection region of the nozzle of the clear head CL1 which is the head on the tip side, R3 and R4 are lit and R5 is extinguished. The ink ejected from the nozzles corresponding to the portions R3 and R4 is irradiated immediately after being adhered, so that the ink has a matte tone. Similarly to the color, the matte area formed by the clear head CL1 also has a low edge printing rate because the banding becomes conspicuous due to a line feed error or the like.

On the other hand, R5, 6, 7, and 8 of the lamp 401, which corresponds to the ejection region of the nozzle of the clear head CL2, which is the head on the rear end side, are turned off. Therefore, the ink discharged from the clear head CL2 is not cured immediately after adhering to the color coating film. Ink that is not cured becomes smooth as the droplets stick to each other and spread wet. Especially in places where the amount of color ink adhered is small, unevenness becomes remarkable depending on the base material and the color ink, and the ink of the ink coating of the clear head CL2 is difficult to get wet and spread cleanly.

Further, since the mat formed by the clear head CL1 penetrates into the uneven portion to reduce the unevenness, the ink coating of the clear head CL2 on the upper layer spreads beautifully. After that, it is cured by R9 of the lamp 401, and a beautiful coating film is completed. At that time, if the print rate of the clear head CL2 is low, it may be difficult for the drops to merge with the adjacent drops, and it may be difficult for the drops to get wet and spread cleanly. It is preferable to make it easier to combine with the drops of.

The adjustment discharge pattern applied to the head on the tip side is not limited to the gradation, and other examples (thinning out, sizing) in which the amount of application at both ends is reduced will be described with reference to FIG.

Further, when the total amount of ink of the clear head CL2 on the rear end side is larger than the amount of ink of the clear head CL1 on the front end side, the smoothing is fine. For example, the printing rate of the head on the front end side with clear ink is set to 30% for the entire head, and the printing rate of the head on the rear end side is set to 90% for the entire head.

Therefore, in order to adjust the amount of ink, the clear head CL1 on the tip side on the side where the amount of ink is small applies the adjustment pattern to the upper head at least at both ends like the gradation pattern as described above.

<Discharge pattern>
Next, the adjustment ejection pattern of the clear ink will be described with reference to FIG.

In FIG. 10, (a) is a bottom view of an example of a discharge head, and (b) to (e) are views for explaining various types of discharge patterns. An example is shown in which the length of any of the discharge patterns shown in FIGS. 10 (b) to 10 (e) in the sub-scanning direction corresponds to the length of the nozzle row N of one head shown in FIG. 10 (a). There is.

As shown in FIG. 8, in order to adjust the discharge and paint the matte region and the gloss region separately, in the matte region, as shown in FIGS. 10 (b) to 10 (d), the discharge state is changed in the sub-scanning direction. A changing adjustment discharge mask (mask of discharge adjustment pattern) is used, and in the gloss region, a uniform mask (mask of uniform pattern) shown in FIG. 10 (e) is used.

FIG. 10B shows a gradation mask as an example of the discharge adjustment mask. Gradation is a process in which the image data of one head is darkened in the center as a whole, and the number of dots (printing ratio) ejected from the nozzle decreases toward the edges.

Here, the printing ratio indicates the ratio of the pixels related to the pixel data corresponding to the nozzles in each head of the head unit to be output by performing the ink ejection operation according to the value of the pixel data. The value.

For example, when the carriage 200 is scanned at a predetermined speed, X drops (X is an integer) can be ejected from a specific nozzle, and the nozzles execute the ejection operation at all positions. %become. However, since the ejection operation may not be performed at all positions, the number of times to apply the output data (driving data) for actually performing the ejection operation with the X droplet as a parameter is defined as the printing rate (%). To do.

FIG. 10C shows an end thinning mask as an example of a discharge adjustment mask. In this example, the printing rate gradually decreases at the predetermined widths E on both ends in the sub-scanning direction of the head. That is, the size of the dots does not change and the number of dots decreases, so that the amount of ink adhered per area is reduced.

Here, the gradation mask and the end thinning mask have in common that dots are thinned out stepwise toward the ends in the areas at both ends. However, in the gradation mask, the gradual darkening is performed in the central part so as to compensate for the thinning at both ends, whereas in the edge thinning mask, the dots are adjusted for the central part where the thinning is not performed. The difference is that no processing is performed.

FIG. 10D shows a drop size adjustment mask as an example of the discharge adjustment mask. In this example, the drop size is gradually reduced at a predetermined width E on both ends of the head in the sub-scanning direction. That is, the number of dots does not change, and the size of each dot to which the ejected droplets are attached becomes smaller (smaller droplets), so that the amount of ink adhered per area is reduced.

Here, when the drop size, which is the discharge amount per drop discharged from the nozzle, is adjusted, for example, one of the preset stepwise discharge amounts for large drops, medium drops, and small drops is selected. It may be selected from the drop size, or the drop size may be adjusted and set from the specified size by finely adjusting the predetermined drop size.

<Movement of position of irradiation part>
FIG. 11 is an enlarged view illustrating the position of the lamp in the irradiation unit 400.

As a premise, the finer the element R of the lamp 401, the more the control is aimed at, but if it is too small, the cost increases. Therefore, when a commercially available lamp having a predetermined width is used, it is difficult for the irradiation range to be exactly the same as the length of the head.

Therefore, if the entire area of the clear head CL2 on the rear end side is to be a gloss region, the matte portion of the clear head CL1 on the front end side will have an about length.

However, since one matte area forms one head image, if the matte area has a halfway length, the matte is incomplete and it becomes banding.

Therefore, it is preferable that the range in which the clear head CL1 on the tip side becomes a mat is extremely short, about 1/4 or less, or extremely long, which is 3/4 or more. If the matte area is extremely short, it becomes a thin matte area and becomes inconspicuous, and if the matte area is extremely long, the printing rate of the part that does not become the matte area is very low, the matte area is almost completed, and banding is performed. This is because it becomes less noticeable.

If the amount of printing is large in the areas where the lamps 401R4 and R5 are lit or not lit, the matte area may expand more than expected due to the effect of leaked light, resulting in banding. It is preferable that the boundary is a place where the printing rate is low so that it is difficult to receive.

That is, the boundary between the lighting and extinguishing of the plurality of lamps is within the range of the predetermined width E (see FIG. 10) at both ends of the clear head CL1 on the tip side, which is thinner than the other portions at both ends in the sub-scanning direction. Set so that it is inside.

Further, in FIGS. 7 and 11, one head on the rear end side for gloss and one head on the front end side for matting are set, but the gloss area and the range of the mat area are set as the gloss area. If at least the line feed width is included, the gloss region can be set to be a part of one rear end side head, a range slightly longer than one rear end side head, a plurality of rear end side heads, and the like. In this case, in one head, the nozzle may be divided into blocks in a gloss area and a matte area.

For example, if the line feed width changes and the head boundary setting in the gloss area and matte area changes, the position of the on / off boundary must also change, but the lamp switching position is the boundary. In the head including, the range of the mat area may not be the position of 1/4 or less, or the position of 3/4 or more.

In that case, in addition to the ON / OFF switching control of the lamp, the switching position is turned on and off by adjusting the position of the region L of the irradiation unit 400 with respect to the region H of the nozzle row in the head unit 300 of the carriage 200. The boundary of may be adjusted to the desired position.

For example, when moving the irradiation unit 400R, the lamp fixing pin 45 is turned to release the fixing, and the lamp group 401 is pushed and pulled, so that the lamp group 401 moves in the sub-scanning direction along the guide rail 44. It will be possible. When the lamp group 401 moves to an arbitrary position, it is fixed by the lamp fixing pin 45 to complete the movement.

Such movement of the lamp groups 401L and 401R of the irradiation unit 400 is performed manually after the line feed width is determined and before printing. It should be noted that the configuration may be such that the lighting unit is automatically moved by the control in the device.

In one scanning movement, as shown in FIG. 9D, in order to form a gloss region with a time lag with respect to the mat region, the regions that can be irradiated by the lamp groups 401L and 401R are recorded from a plurality of heads. It is preferable that the position is set on the rear end side in the sub-scanning direction in the sub-scanning direction so as to be longer than the region for ejecting clear ink to the medium by at least the line feed width.

For example, when the gloss region is formed only by the lamp 401R9 on the rearmost end side, the line feed width is set to B or less. When the line feed width is longer (wider) than B, the two lamps 401R8 and 401R9 on the rear end side may be set as lamps forming a gloss region.

Further, in FIGS. 8 and 9, an example in which the head width = line feed width is formed by a single scan so that the region of the head unit in the sub-scanning direction is provided by three scans has been described. The matte gloss allocation settings in can also be applied to multi-pass print sequences.

When the print sequence is multi-pass, a line feed width shorter than that of the head is used for line feed in the sub-scanning direction. For example, in the sub-scanning direction, when an image in the sub-scanning direction is formed by scanning 24 times (scanning movement) with respect to the head unit, the area for ejecting colored ink is 1/3 of the head unit, so each head The number of scans per area is 8 (the number of line breaks is 7). The number of scans (scanning) is an example of 4-pass 1/2 interlacing in which the number of strikes (passes) in the main scanning direction X is 4 times and the number of strikes (interlaces) in the sub-scanning direction Y is 2 times. An example in which the number) is 8 times (n = 8) will be described.

In this case, as shown in FIG. 9 (b), the clear ink is started to be ejected from the head on the front end side after the ninth scan (n + 1), and as shown in FIG. 9 (c), on the rear end side. The clear ink starts to be ejected from the head from the 17th scan (2n + 1) onward.

Further, as shown in FIG. 9D, irradiation is started for the region where the clear ink is ejected from the head on the rear end side from the 25th scan (3n + 1) or later.

<Discharge adjustment / irradiation adjustment flow>
Next, the discharge adjustment / irradiation adjustment according to the first embodiment will be described with reference to FIG. FIG. 12 is a control flow of discharge / irradiation adjustment according to the first embodiment.

In S1, the print sequence and line feed width are set.

In S2, the widths of the matte area and the gloss area are set. In the case of multipath, the width of the gloss area is set so as to be the same as or larger than the line feed width in S1. Alternatively, in the case of a single scan, the width of the gloss region is set to be the same as or larger than the region excluding the overlap region between scans.

In S3, the positions of the lamp groups 401L and 401R of the irradiation unit are moved. If this step is unnecessary, such as when the line feed width is the same from the previous scan, this step may be omitted.

In S3, in the lamp groups 401L and 401R, the area where the lamp groups 401L and 401R can be irradiated in one scanning movement is behind the area where the clear ink is ejected from the plurality of heads to the recording medium in the sub-scanning direction. The position is set on the end side so as to be longer by at least the line feed width.

In S4, the adjustment discharge pattern is selected in the tip side head. Specifically, the adjustment discharge pattern shown in FIGS. 10 (b) to 10 (d), in which the amount of liquid applied at both ends in the sub-scanning direction is smaller than that in the center portion, is one of the gradation / thinning / drop size adjustment. Select and set for the head on the tip side.

In S5, the lamp is turned on / off according to the control information set in the irradiation unit so as to follow the length of the matte area / gloss area set in S2 in the sub-scanning direction. In the example of FIG. 7, the lamps 401R1, R2, R3, R4, and R9 are turned on, and the lamps R5, R6, R7, and R8 are turned off.

In S6, while moving in the main scanning direction, on the tip side of the region where the clear ink is ejected, a colored head that ejects the color ink applies a gradation mask to each head and ejects the ink.

In S7, the clear head that ejects clear ink while moving in the main scanning direction masks the set adjustment ejection pattern on the front end side and ejects the clear ink in a uniform pattern on the rear end side.

Here, for example, assuming that the heads that eject colored ink are m rows in the sub-scanning direction, the heads that eject clear ink are two rows, and the number of scans per head region is n times, the number of scans per recording medium 101 is The clear ink is not ejected until the (m × n) th scan (in FIG. 9 (a), the first scan is due to m = 1 and n = 1) when scanning is started from the rearmost end side.

Further, from the rear end side of the recording medium 101 to the {(m + 1) × n} th scan (the second scan in FIG. 9B), the clear ink is ejected only to the head on the front end side, and the rear end is ejected. Not implemented with the head on the side.

In S8, at the end of the movement in the main scanning direction, the predetermined block of the lamp group 401 of the irradiation unit 400 irradiates the region of the liquid applied on the recording medium with the light by the tip-side head. In this way, the tip-side head cures the liquid region applied on the recording medium by irradiating it with light immediately after ejection to form a mat.

Note that S6 to S8 are executed within one scan in the main scanning direction (see FIG. 9C). Then, after the {(m + 1) × n + 1} scan (third in the example of FIG. 9C), irradiation is started on the region where the clear ink is ejected from the head on the rear end side. The gloss region begins to be formed after the {(m + 2) n + 1} scan (the fourth scan in the example of FIG. 9 (d)). That is, the gloss region is irradiated from the nth scan after the clear ink is ejected from the head on the rear end side.

In S9, the carriage 200 is moved in the sub-scanning direction by the line feed width.

The above operation is repeated until printing is stopped in S10.

The colored heads 301K1, Y1, M1, C1, S1 and the like provided on the most tip side with respect to the position facing the end of the ejection region on the recording medium 101 defined based on the image data are clear colors. It reaches before the heads 301CL1 and CL2. Therefore, when the colored heads 301K1, Y1, M1, C1, and S1 reach the positions facing the end of the discharge region on the recording medium 101, the discharge is stopped in order from the nozzles located on the tip side. The clear heads 301CL1 and CL2 eject clear ink so as to cover the entire area where the colored ink droplets have landed on the recording medium 101 by the colored heads 301K1, Y1, M1, C1 and S1 even after the colored heads have finished ejecting. to continue. Further, the clear ink droplets ejected from the rear end side head 301CL2 are irradiated with light with a time lag so that the uppermost layers of all the ejection regions are all gloss regions.

When printing is stopped, the lamps 401R1, R2, R3, R4, and R9, which are the blocks that have been lit, are turned off in the lighting unit.

By such control, the color and clear ink ejected by the head on the front end side are evened out to form a matte area, and the ink ejected by the head on the rear end side becomes a uniform leveling state and has a beautiful gloss. It is possible to obtain an area by a series of operations (high speed).

Therefore, since the mat layer and the overcoat layer are formed in one job without generating the data of the mat layer, the productivity of the overcoat layer having no unevenness in glossiness can be improved. That is, in the embodiment of the present invention, it is possible to form an overcoat layer having an even glossiness while increasing productivity.

In this flow, for simplification of the explanation, the head on the front end side is set as matte and the head on the rear end side is set as gloss. For example, as shown in FIG. 7, in the head that ejects clear ink. , At least a part of the tip side head may be set as a mat, and the rear end side head and the rest of the front end side head may be set as a gloss.

In that case, in S8, at the end of movement in the main scanning direction, the predetermined block of the lamp group 401 of the irradiation unit 400 irradiates the region of the liquid applied on the recording medium with the light by the tip-side head. In this way, at least a part of the tip side of the tip side head irradiates the area of the liquid applied on the recording medium with light immediately after the discharge to cure the region to form a mat.

Further, in S8, the liquid region imparted on the recording medium 101 by the rear end side head and the remaining portion on the rear end side of the front end side head is not irradiated in S8 immediately after S7, and after a line break ( A gloss region is formed by being irradiated by the lighting portion R9 of the lamp in the scan after being left for a plurality of scans (n times) while leveling in S9).

In the above example, an example in which two types of ink, a colored ink droplet and a clear ink droplet, are landed has been described, but also for a printing mode in which a primer layer is formed as a base between the medium and the colored ink droplet. , The above control of the overcoat layer can be carried out. In the print mode constituting the primer layer, the control above the colored ink droplets is the same scanning for the clear ink droplets and the colored ink droplets on the tip side head, as in FIG. 9 above. Therefore, the desired matte region and gloss region can be formed by irradiating the clear ink droplets on the rear end side head with light in the next and subsequent scans.

In the flow of FIG. 12, the tip side head is described as the "tip side nozzle" and the rear end side head is described as the "rear end side nozzle", but the "tip side nozzle" is referred to as the "tip side head". The "rear end side nozzle" may be "rear end side head + remaining nozzle of the front end side head".

When the matte area and the gloss area are set by using one clear head, the "tip side nozzle" is a part of the tip side nozzles in one head, and the "rear end side nozzle". Is the nozzle of the rest of the rear end side of one head. In this case, it is preferable to paint the adjustment discharge pattern separately on the front end side and the rear end side in the clear head, but a uniform discharge pattern may be set.

<Scanning position of the second embodiment>
In addition, in FIGS. 7 to 12, in the sub-scanning operation in the first embodiment, irradiation / ejection is performed in a configuration in which the carriage 200 including the head unit 300 and the irradiation unit 400 is moved relative to the recording medium. Although the control example has been described, the above control can also be applied to the second embodiment shown in FIG.

In the present embodiment, in the illumination adjustment and ejection adjustment control in the sub-scanning direction, a matte region is formed on the head on the upstream side in the transport direction of the recording medium, and a gloss region is formed on the head on the downstream side in the transport direction of the recording medium 101. ..

Therefore, in the present embodiment, the "head on the front end side" in S4, S7, and S8 in the flow of FIG. 12 is defined as the "head on the upstream side in the recording medium transport direction", and the "head on the rear end side" is referred to as "head on the rear end side". The head on the downstream side in the recording medium transport direction. Further, instead of moving the carriage in S9 by the line feed in the sub-scanning direction, the recording medium is moved by the line feed in the sub-scanning direction by the transport belt. Other than that, it is almost the same as the first embodiment.

Also in the present embodiment, a plurality of heads for ejecting clear ink are provided in the recording medium transport direction, and the irradiation start timing is different between the head on the upstream side and the head on the downstream side in the transport direction, so that at least the second scanning is performed. After that, since a gloss layer is formed on the mat layer for each line feed width, the uppermost layer on the downstream side to be completed is always a gloss layer.

By such control, also in the present embodiment, the unevenness due to the color is leveled in the matte region upstream in the clear region discharge region, the downstream is in a uniform leveling state, and a beautiful gloss can be obtained by a series of operations (high speed). .. Therefore, since the mat layer and the overcoat layer are formed in one job without generating the data of the mat layer, the productivity of the overcoat layer having no unevenness in glossiness can be improved. That is, an overcoat layer having an even glossiness is formed while increasing productivity.

In the above description, the upstream head is referred to as an "upstream nozzle" and the downstream head is referred to as a "downstream nozzle". However, in the present embodiment, the "upstream nozzle" is upstream. A part of the nozzles on the upstream side of the side head, the "downstream side nozzle" may be the downstream side head + the remaining nozzles on the downstream side of the upstream side head.

When setting the matte area and the gloss area using one clear head, the "upstream nozzle" is a part of the upstream nozzle in one head, and the "downstream nozzle" is. Nozzles for the rest of the downstream side of one head. In this case, it is preferable to paint the adjustment discharge pattern separately on the upstream side and the downstream side in the clear head, but a uniform discharge pattern may be set for the head.

Although the preferred embodiment of the present invention has been described in detail above, the present invention is not limited to the specific embodiment, and within the scope of the gist of the embodiment of the present invention described in the claims. Various modifications and changes are possible.

For example, in the above-described embodiment, the inkjet recording device including the recording head according to the present invention has been described, but the liquid ejection head according to the present invention and its control are widely applied to devices that eject liquid including the inkjet recording apparatus. Can be applied.

In the present application, the "liquid discharge device" is a device including a liquid discharge head or a liquid discharge unit, which drives the liquid discharge head to discharge the liquid.

The above-mentioned "material to which a liquid can adhere" means a material to which a liquid can adhere at least temporarily, such as one that adheres and adheres, and one that adheres and permeates. Specific examples include media such as paper, recording paper, recording paper, film, cloth and other recording media, electronic substrates, electronic components such as piezoelectric elements, powder layers (powder layers), organ models, and inspection cells. Yes, including anything to which the liquid adheres, unless otherwise specified.

The material of the above-mentioned "material to which liquid can be attached" may be paper, thread, fiber, cloth, leather, metal, plastic, glass, wood, ceramics or the like as long as the liquid can be attached even temporarily.

Further, the pressure generating means used for the "liquid discharge head" is not limited. For example, a piezoelectric actuator (which may use a laminated piezoelectric element), a thermal actuator that uses an electrothermal conversion element such as a heat generating resistor, or an electrostatic actuator composed of a diaphragm and a counter electrode can be used.

In addition, image formation, recording, printing, printing, printing, modeling, etc. in the terms of the present application are all synonymous.

10,1,30 Inkjet recording device (image forming device, liquid ejection device)
2 PC (computer)
3 Controller unit (computer)
19 Guide rod (moving part)
22 Irradiation part (lamp group)
27 Recording control unit 270 Liquid discharge amount adjustment unit 28 Irradiation control unit 200 Carriage (main scanning unit)
101 Recording medium (base material)
20,200 carriage (main scanning unit)
30,300 Head unit 301 Head 301CL1, 301CL2 Clear head 301CL1 Tip side head (upstream side head, tip side nozzle, upstream side nozzle)
301CL2 Rear end side head (downstream side head, rear end side nozzle, downstream side nozzle)
40 (40L, 40R), 400 (400L, 400R) Irradiation unit 401L, 401R Lamp group (irradiation part)
401L1-L9, 401R1-R9 lamps (irradiation block, block)
29 Guide rail (moving part)
600 Conveying unit 71 Conveying belt (moving part)
72a, 72b Conveying roller (moving part)

Japanese Unexamined Patent Publication No. 2015-214133

Claims (15)

A head unit in which a plurality of nozzles for discharging an active energy ray-curable liquid on a recording medium are provided as a nozzle row in the sub-scanning direction, and
An irradiation unit that is connected to the head unit and that irradiates the liquid on the recording medium with light of active energy rays that cures the liquid.
A scanning movement in which the head unit and the irradiation unit are moved in a scanning direction orthogonal to the sub-scanning direction with respect to the recording medium, and the head unit and the irradiation unit are relatively subordinate to the recording medium. A moving unit that alternately performs sub-scanning movements that move in the scanning direction, and
An irradiation control unit that controls lighting and extinguishing by dividing the sub-scanning direction of the irradiation unit is provided.
At least a part of the scanning movement, the head unit and the irradiation unit discharge a liquid to the recording medium to irradiate the recording medium with light.
After discharging the liquid from the plurality of nozzles to the recording medium, the liquid applied to the recording medium by the nozzles on the rear end side in the traveling direction of the sub-scanning direction of the head unit and the irradiation unit is irradiated with light. A liquid ejection device that makes the time until the liquid is started to be irradiated to the liquid applied on the recording medium by the nozzle on the tip side in the traveling direction longer than the time until the liquid is started to be irradiated. Irradiation of the liquid applied to the recording medium by the nozzle on the tip side is performed within the same scanning movement for discharging the liquid from the plurality of nozzles to the recording medium.
The irradiation of the liquid applied to the recording medium by the nozzle on the rear end side is performed by one or a plurality of sub-scanning movements after the scanning movement for ejecting the liquid from the plurality of nozzles to the recording medium. The liquid discharge device according to claim 1, which is later performed within another scanning movement. The region that can be irradiated by the irradiation unit is set longer on the rear end side in the sub-scanning direction than the region where the liquid is discharged from the plurality of nozzles to the recording medium in one scanning movement.
In the scanning movement, the irradiation region of the irradiation unit at a position corresponding to the nozzle on the front end side and the sub-scanning direction, and the irradiation region located on the rear end side in the sub-scanning direction with respect to the nozzle on the rear end side. The liquid discharge device according to claim 2, wherein the irradiation area of the irradiation unit is lit, and the irradiation area of the irradiation unit at a position corresponding to the nozzle on the rear end side and the sub-scanning direction is extinguished. The head unit has a plurality of heads each provided with a plurality of nozzles for discharging the liquid in the sub-scanning direction.
The nozzle on the tip side is a head on the tip side in the traveling direction.
The liquid discharge device according to any one of claims 1 to 3, wherein the nozzle on the rear end side is a head on the rear end side in the traveling direction. The head unit has a plurality of heads each provided with a plurality of nozzles for discharging the liquid in the sub-scanning direction.
The nozzle on the tip side is a part of the nozzle on the tip side of the head on the tip side in the traveling direction.
The liquid discharge according to any one of claims 1 to 3, wherein the nozzle on the rear end side is a nozzle for the entire head on the rear end side in the traveling direction and the remaining portion on the rear end side of the head on the front end side. apparatus. A claim including a liquid discharge amount adjusting unit that adjusts the amount of liquid applied on the recording medium by the head on the front end side to be less than the amount of liquid applied on the recording medium by the head on the rear end side. Item 4. The liquid discharge device according to Item 4. The liquid discharge amount adjusting unit discharges the liquid at both ends in the sub-scanning direction so as to be smaller than that at the center of the head on the front end side, and uniformly on the head on the rear end side. The liquid discharge device according to claim 6, wherein the liquid is discharged. The liquid discharge amount adjusting unit adjusts the liquid discharge amount in the head on the tip side so as to have a gradation in which the applied amount is gradually reduced toward both ends in the sub-scanning direction. Liquid discharge device. The liquid discharge amount adjusting unit adjusts the liquid discharge amount of the head on the tip side so as to reduce the number of dots to be discharged from predetermined areas at both ends in the sub-scanning direction. Liquid discharge device. The liquid discharge amount adjusting unit according to claim 7, wherein the head on the tip side adjusts the liquid discharge amount in a predetermined area at both ends in the sub-scanning direction so as to reduce the drop size of the dots to be discharged. Liquid discharge device. When forming an image with multipath that scans n times per head area,
The irradiation of the liquid applied to the recording medium by the nozzle on the rear end side is performed within the nth scanning movement after the scanning movement for ejecting the liquid from the plurality of nozzles to the recording medium. The liquid discharge device according to any one of claims 4 to 10. The head unit has one head provided with a plurality of nozzles for discharging the liquid in the sub-scanning direction.
The nozzle on the tip side is a part of the nozzle on the tip side in the traveling direction of the head.
The liquid discharge device according to any one of claims 1 to 4, wherein the nozzle on the rear end side is a nozzle for the remaining portion of the head on the rear end side in the traveling direction. A head unit in which a plurality of nozzles for discharging an active energy ray-curable liquid on a recording medium are provided as a nozzle row in the sub-scanning direction, and
An irradiation unit that is connected to the head unit and that irradiates the liquid on the recording medium with light of active energy rays that cures the liquid.
A scanning movement that moves the head unit and the irradiation unit in a scanning direction orthogonal to the sub-scanning direction with respect to the recording medium, and the sub-scanning that moves the recording medium relative to the head unit and the irradiation unit. A moving unit that alternately performs sub-scanning movements that move in the scanning direction, and
An irradiation control unit that controls lighting and extinguishing by dividing the sub-scanning direction of the irradiation unit is provided.
At least a part of the scanning movement, the head unit and the irradiation unit discharge a liquid to the recording medium to irradiate the recording medium with light.
After discharging the liquid from the plurality of nozzles to the recording medium, the time until the liquid applied to the recording medium by the nozzles on the downstream side in the recording medium transfer direction starts to be irradiated with light is the time required for the recording medium transfer. A liquid discharge device that prolongs the time required to start irradiating the liquid applied to the recording medium by the nozzle on the upstream side in the direction. Irradiation control method in a liquid discharge device
The liquid discharge device includes a head unit in which a plurality of nozzles for discharging active energy ray-curable liquid on a recording medium are provided as a nozzle row in the sub-scanning direction; the head unit is connected to the head unit, and light is emitted from the head unit. An irradiation unit that irradiates a liquid on a recording medium with light of an active energy ray that cures the liquid by dividing the sub-scanning direction and switching between lighting and extinguishing; the head unit and the irradiation unit A scanning movement that moves the head unit and the irradiation unit in a scanning direction orthogonal to the sub-scanning direction with respect to the recording medium, and a sub-scanning movement that moves the head unit and the irradiation unit in the sub-scanning direction relative to the recording medium. It is equipped with a moving part that alternately carries out
After discharging the liquid from the plurality of nozzles to the recording medium, the liquid applied to the recording medium by the nozzle on the tip side in the traveling direction of the sub-scanning direction of the head unit and the irradiation unit is irradiated with light. Steps and
After ejecting the liquid from the plurality of nozzles to the recording medium, after a lapse of a predetermined time, the liquid applied onto the recording medium by the nozzle on the rear end side in the traveling direction is slower than the irradiation of light on the nozzle on the front end side. An irradiation control method in a liquid discharge device having a step of irradiating light. Irradiation control program for liquid discharge devices
The liquid discharge device is connected to a head unit in which a plurality of nozzles for discharging active energy ray-curable liquid on a recording medium are provided as a nozzle row in the sub-scanning direction, and the light is emitted. An irradiation unit that irradiates a liquid on a recording medium with light of an active energy ray that cures the liquid by dividing the sub-scanning direction and switching between lighting and extinguishing; the head unit and the irradiation unit A scanning movement that moves the head unit and the irradiation unit in a scanning direction orthogonal to the sub-scanning direction with respect to the recording medium, and a sub-scanning movement that moves the head unit and the irradiation unit in the sub-scanning direction relative to the recording medium. It is equipped with a moving part that alternately carries out
After discharging the liquid from the plurality of nozzles to the recording medium, the liquid applied to the recording medium by the nozzle on the tip side in the traveling direction of the sub-scanning direction of the head unit and the irradiation unit is irradiated with light. Processing and
After ejecting the liquid from the plurality of nozzles to the recording medium, after a lapse of a predetermined time, the liquid applied onto the recording medium by the nozzle on the rear end side in the traveling direction is slower than the irradiation of light on the nozzle on the front end side. An irradiation control program in a liquid discharge device that executes a process of irradiating light with a computer.