JP5560643B2 - Liquid ejection device - Google Patents

Description

  The present invention relates to a liquid ejection apparatus.

  There is a liquid ejecting apparatus (for example, a printer) that ejects liquid (for example, ink) onto a medium (paper, cloth, OHP sheet, or the like). In such a liquid ejecting apparatus, for example, color ink containing a pigment as a colorant is used to print an image. In addition, a technique for processing (for example, coating) the surface of a medium using a colorless and transparent liquid (clear ink) that does not contain a colorant such as a pigment together with such a color ink has been developed. (For example, refer to Patent Document 1).

JP 2003-286428 A

In the liquid ejection device as described above, when printing a low-gloss image quality (matte) image with reduced surface gloss, a medium with uneven surface is used, and the surface gloss is high. When printing an image having a high image quality (gross tone), a medium having a smooth surface was used. As described above, when printing an image, it is necessary to prepare a medium according to the texture, which is troublesome.
Accordingly, an object of the present invention is to easily adjust the texture of an image.

A main invention for achieving the above object is a processing liquid for processing the surface of a medium, a processing liquid nozzle for discharging a processing liquid that is cured when irradiated with light onto the medium, and a color liquid. A color nozzle that discharges the medium, a conveyance unit that conveys the medium in a conveyance direction and in a direction opposite to the conveyance direction, a first irradiation unit that irradiates the light, and the color nozzle to the medium. After the liquid is discharged to form a color image, the medium is transported in the reverse direction, the processing liquid is discharged from the processing liquid nozzle onto the color image, and the processing liquid is supplied to the first irradiation unit. And a controller for irradiating the light. The controller changes the irradiation energy of the light from the first irradiating unit in accordance with the setting of the texture.

  Other features of the present invention will become apparent from the description of the present specification and the accompanying drawings.

1 is a block diagram of an overall configuration of a printer. FIG. 3 is a schematic view around a print area. It is explanatory drawing of the nozzle arrangement | positioning of each head. 4A to 4C are explanatory diagrams of the relationship between the UV irradiation energy and the shape of the UV ink (dot) in temporary curing. FIG. 8 is an explanatory diagram of a configuration of a printer of a comparative example. FIG. 6 is a flowchart of processing performed by a printer driver when printing by a printer. It is a figure which shows an example of the screen displayed on a computer. It is a flowchart of the printing process by the printer of 1st Embodiment. It is a flowchart of an irradiation condition setting process. 10A and 10B are conceptual diagrams of printed matter according to the first embodiment. It is the schematic of the printing area periphery in 2nd Embodiment. It is a flowchart of the printing process by the printer of 2nd Embodiment. 13A and 13B are conceptual diagrams of printed matter according to the second embodiment. It is the schematic of the printing area periphery in 3rd Embodiment. It is a flowchart of the printing process by the printer of 3rd Embodiment.

  At least the following matters will become clear from the description of the present specification and the accompanying drawings.

A processing liquid for processing the surface of a medium, a head that discharges a processing liquid that is cured when irradiated with light onto the medium, a first irradiation unit that irradiates light for temporary curing, and a main curing A second irradiating unit that irradiates the light, and forming a dot on the medium by ejecting the machining liquid from the head, and further irradiating the dot formed on the medium from the first irradiating unit. , A controller that irradiates light from the second irradiation unit to the dots irradiated with light from the first irradiation unit, and the irradiation energy of light from the first irradiation unit according to the setting of the texture of the image A liquid ejecting apparatus including a controller for changing the function is clarified.
According to such a liquid ejecting apparatus, it is possible to easily adjust the texture of the image.

In such a liquid ejection apparatus, the irradiation energy of light emitted from the first irradiation unit when the texture of the image is set to a matte tone, the irradiation energy of the light when the texture of the image is set to a glossy tone It is desirable that it is larger than the irradiation energy of the light irradiated from the first irradiation unit.
According to such a liquid ejecting apparatus, the texture of the image can be changed to a matte or glossy tone by changing the magnitude of the irradiation energy.

In such a liquid ejection apparatus, when the texture of the image is set to a matte tone, the irradiation energy of the light irradiated from the first irradiation unit is 15 mJ / cm ^{2 to} 30 mJ / cm ² , When the texture is set to a glossy tone, the irradiation energy of the light irradiated from the first irradiation unit is preferably 5 mJ / cm ^{2 to} 15 mJ / cm ² .

The liquid ejecting apparatus may further include a plurality of color heads that eject color liquid for each color, and the controller may cause the plurality of color heads to eject color liquids, thereby causing an image on the medium. After printing, the processing liquid may be discharged onto the medium on which the image is printed.
According to such a liquid ejecting apparatus, it is possible to continuously perform image printing and surface processing.

In such a liquid ejection apparatus, the color liquid may be a liquid that is cured when irradiated with light.
According to such a liquid ejecting apparatus, it is possible to print on a medium that does not easily absorb liquid.

In this liquid ejection apparatus, the color liquid may be an aqueous liquid.
According to such a liquid ejecting apparatus, it is possible to adjust the texture regardless of the image (the presence or absence of the image or the density of the image), and the gloss can be made more uniform.

  In the following embodiments, a line printer (printer 1) will be described as an example of the liquid ejection device.

=== First Embodiment ===
<About printer configuration>
FIG. 1 is a block diagram of the overall configuration of the printer 1. FIG. 2 is a schematic view around the print area.

  The printer 1 is a printing device that prints an image on a medium such as paper, cloth, or film, and is communicably connected to a computer 110 that is an external device.

A printer driver is installed in the computer 110. The printer driver is a program for displaying a user interface on a display device (not shown) and converting image data output from an application program into print data. This printer driver is recorded on a recording medium (computer-readable recording medium) such as a flexible disk FD or a CD-ROM. Alternatively, the printer driver can be downloaded to the computer 110 via the Internet. In addition, this program is comprised from the code | cord | chord for implement | achieving various functions.
Then, the computer 110 outputs print data corresponding to the image to be printed to the printer 1 in order to cause the printer 1 to print an image.

  The printer 1 of the present embodiment is an apparatus that prints an image on a medium by ejecting ultraviolet curable ink (hereinafter referred to as UV ink) that is cured by irradiation with ultraviolet light (hereinafter referred to as UV) as an example of a liquid. The UV ink is an ink containing an ultraviolet curable resin, and is cured by undergoing a photopolymerization reaction in the ultraviolet curable resin when irradiated with UV. The printer 1 of the present embodiment uses CMYK four-color UV ink (color ink) and colorless and transparent UV ink (clear ink) for printing an image.

  The printer 1 according to this embodiment includes a transport unit 20, a head unit 30, an irradiation unit 40, a detector group 50, and a controller 60. The printer 1 that has received print data from the computer 110 that is an external device controls each unit (the transport unit 20, the head unit 30, and the irradiation unit 40) by the controller 60, and prints an image on a medium according to the print data. The controller 60 controls each unit based on the print data received from the computer 110 and prints an image on a medium. The situation in the printer 1 is monitored by the detector group 50, and the detector group 50 outputs the detection result to the controller 60. The controller 60 controls each unit based on the detection result output from the detector group 50.

  The transport unit 20 is for transporting a medium (for example, paper) in a predetermined direction (hereinafter referred to as a transport direction). The transport unit 20 includes an upstream transport roller 23 </ b> A, a downstream transport roller 23 </ b> B, and a belt 24. When a transport motor (not shown) rotates, the upstream transport roller 23A and the downstream transport roller 23B rotate, and the belt 24 rotates. The medium fed by a paper feed roller (not shown) is conveyed by the belt 24 to a printable area (area facing the head). As the belt 24 transports the medium, the medium moves in the transport direction with respect to the head unit 30. The paper S that has passed through the printable area is discharged to the outside by the belt 24. Note that the medium being transported is electrostatically attracted or vacuum attracted to the belt 24.

The head unit 30 is for ejecting UV ink onto a medium. The head unit 30 discharges each ink to the medium being conveyed, thereby forming dots on the medium and printing an image on the medium. The printer 1 of the present embodiment is a line printer, and each head of the head unit 30 can form dots for the medium width at a time. As shown in FIG. 2, in order from the upstream side in the transport direction, a black ink head K that discharges black UV ink, a cyan ink head C that discharges cyan UV ink, and a magenta ink that discharges magenta UV ink. A head M, a yellow ink head Y that discharges yellow UV ink, and a clear ink head CL that discharges clear ink are provided. Hereinafter, each head that discharges color ink (black, cyan, magenta, yellow) is also referred to as a color ink head, and the clear ink head CL that discharges clear ink is also referred to as a clear ink head.
Details of the configuration of the head unit 30 will be described later.

  The irradiation unit 40 irradiates UV toward the UV ink that has landed on the medium. The dots formed on the medium are cured by receiving UV irradiation from the irradiation unit 40. The irradiation unit 40 of the present embodiment includes provisional curing irradiation units 42 a to 42 e and a main curing irradiation unit 44.

  The pre-curing irradiation units 42a to 42e irradiate UV for pre-curing the dots formed on the medium. In the present embodiment, the term “temporary curing” refers to curing performed to suppress bleeding between inks and spreading of dots.

  The pre-curing irradiation unit 42 a is provided on the downstream side in the transport direction of the black ink head K, and the pre-curing irradiation unit 42 b is provided on the downstream side in the transport direction of the cyan ink head G. In addition, the pre-curing irradiation unit 42c is provided on the downstream side in the transport direction of the magenta ink head M, and the pre-curing irradiation unit 42d is provided on the downstream side in the transport direction of the yellow ink head Y. The provisional curing irradiation section 42e is provided on the downstream side in the transport direction of the clear ink head CL. The temporary curing irradiation unit 42e corresponds to the first irradiation unit.

  The length in the medium width direction of these temporary curing irradiation portions 42a to 42e is equal to or greater than the medium width. The pre-curing irradiation units 42 a to 42 e irradiate the dots formed by the corresponding heads of the head unit 30 with the pre-curing UV.

The provisional curing irradiation unit 42 of the present embodiment includes a light emitting diode (LED) as a light source for UV irradiation. The LED can easily change the irradiation energy by controlling the magnitude of the input current.
The details of temporary curing will be described later.

  The main curing irradiation unit 44 irradiates UV for main curing the dots formed on the medium. In the present embodiment, the main curing is a curing performed for completely curing the dots.

  The main curing irradiation section 44 is provided on the downstream side in the transport direction from the provisional curing irradiation section 42e. Further, the length of the main curing irradiation unit 44 in the medium width direction is equal to or greater than the medium width. The main curing irradiation unit 44 irradiates the dots formed by the heads of the head unit 30 with UV. The main curing irradiation unit 44 corresponds to a second irradiation unit.

The main curing irradiation unit 44 of the present embodiment includes a lamp (a metal halide lamp, a mercury lamp, or the like) as a UV irradiation light source.
Details of the main curing will be described later.

  The detector group 50 includes a rotary encoder (not shown), a paper detection sensor (not shown), and the like. The rotary encoder detects the rotation amount of the upstream side conveyance roller 23A and the downstream side conveyance roller 23B. The transport amount of the medium can be detected based on the detection result of the rotary encoder. The paper detection sensor detects the position of the leading edge of the medium being fed.

  The controller 60 is a control unit (control unit) for controlling the printer. The controller 60 includes an interface unit 61, a CPU 62, a memory 63, and a unit control circuit 64. The interface unit 61 transmits and receives data between the computer 110 that is an external device and the printer 1. The CPU 62 is an arithmetic processing unit for controlling the entire printer. The memory 63 is for securing an area for storing a program of the CPU 62, a work area, and the like, and includes storage elements such as a RAM and an EEPROM. The CPU 62 controls each unit via the unit control circuit 64 in accordance with a program stored in the memory 63.

<About printing operation>
When the printer 1 receives print data from the computer 110, the controller 60 first rotates a paper feed roller (not shown) by the transport unit 20 and sends a medium to be printed onto the belt 24. The medium is conveyed on the belt 24 without stopping at a constant speed, and passes under the head unit 30 and the irradiation unit 40. During this time, the controller 60 intermittently ejects ink from the nozzles of each head of the head unit 30 to form dots on the medium and irradiates UV from each irradiation unit of the irradiation unit 40. Thus, an image is printed on the medium. Finally, the controller 60 discharges the medium on which image printing has been completed.

<About the configuration of the head>
As shown in FIG. 2, the printer 1 of this embodiment has a color ink head and a clear ink head.
The color ink head ejects UV ink for printing an image for each ink color. In this embodiment, as a color ink head, a black ink head K, a cyan ink head C, a magenta ink head M, and a yellow ink head Y are provided in order from the upstream side in the transport direction. The color ink head is provided upstream of the clear ink head in the transport direction. The nozzle arrangement of the color ink head will be described later.
The clear ink head CL discharges colorless transparent ink, which is a kind of processing liquid for processing the surface of the medium, onto the entire surface of the medium (hereinafter also referred to as application).

FIG. 3 is an explanatory diagram of an example of the nozzle arrangement of each head.
FIG. 3 shows the arrangement of color ink heads or clear ink heads. Each of these heads is provided with two nozzle rows of “A row” and “B row” as shown in the figure.
The nozzles in each row are arranged at an interval (nozzle pitch) of 1/180 inch along a direction (nozzle row direction) intersecting the transport direction. Further, the position in the nozzle row direction of the nozzles in the A row and the position in the nozzle row direction of the nozzles in the B row are shifted by a half nozzle pitch (1/360 inch). As a result, color dots or clear dots can be formed with a resolution of 1/360 inch.
The length of each nozzle row in the nozzle row direction is equal to or longer than the length corresponding to the medium width, whereby dots corresponding to the medium width can be formed at a time.

<About temporary curing and main curing>
The printer 1 according to the present embodiment includes provisional curing irradiation units 42a to 42e and a main curing irradiation unit 44 as the irradiation unit 40, and performs two-stage curing, that is, temporary curing and main curing after dot formation. ing. Hereinafter, the function of each curing will be described.

Temporary curing is curing for suppressing bleeding between inks and spreading of dots by curing only the surface of the dots. In this temporary curing, the irradiation energy of UV irradiated per unit area of the medium (hereinafter simply referred to as irradiation energy) is small, and the UV ink (dot) is not completely cured even after the temporary curing. . The irradiation energy (mJ / cm ² ) is the product of the irradiation intensity (mW / cm ² ) and the irradiation time (sec). In this embodiment, the medium conveyance speed is constant (irradiation time by each irradiation unit is constant). Therefore, the UV irradiation energy depends on the irradiation intensity.

4A to 4C are explanatory diagrams of the relationship between the UV irradiation energy and the shape of the UV ink (dot) in temporary curing. In addition, the irradiation energy of UV becomes small in order of FIG. 4A, FIG. 4B, and FIG. 4C.
When the irradiation energy of UV is large, for example, as shown in FIG. 4A. In this case, it is possible to suppress bleeding between inks and spread of dots, but the gloss becomes worse because the unevenness of the medium surface constituted by the dots becomes large.
On the other hand, when UV irradiation energy is small, for example, as shown in FIG. 4C. In this case, the gloss is good. However, bleeding tends to occur between other inks.

The main curing is curing for completely curing the ink. The UV irradiation energy in the main curing is larger than the UV irradiation energy in the temporary curing. Specifically, the UV irradiation energy for temporary curing is 3 to 30 mJ / cm ² , whereas the UV irradiation energy for main curing is 200 to 500 mJ / cm ² .

<About Comparative Example>
FIG. 5 is an explanatory diagram of the configuration of the printer of the comparative example. In this comparative example, water-based ink is used as color ink and clear ink instead of UV ink. Further, since water-based ink is used, no UV irradiation section (temporary curing irradiation section and main curing irradiation section) is provided.

  In this comparative example, the medium is transported on the transport belt 24 without stopping at a constant speed, and sequentially below the black ink head K, cyan ink head C, magenta ink head M, yellow ink head Y, and clear ink head CL. Pass through. During this time (while the medium passes under each head), ink is ejected from the nozzles of each head according to instructions from the controller 60. As a result, a color image of four color inks and a coating layer of clear ink are formed on the medium.

In this comparative example, when printing a low-gloss image quality (matte) image with reduced surface gloss, a medium with uneven surface was used, and a high-gloss image quality (gross gloss) with increased surface gloss. When printing a tone image, it is necessary to use a medium having a smooth surface. In this way, a medium corresponding to the texture of the image to be printed must be prepared.
Therefore, in this embodiment, the texture of the image can be easily adjusted without changing the medium.

  In this comparative example, the clear ink is used for coating the surface. However, since the water-based ink has no elasticity, there is a problem that even if it is coated, it is easily damaged. In the present embodiment, UV ink is used for coating so that the surface can be protected more reliably.

<Regarding the Printing Process of the First Embodiment>
FIG. 6 is a flowchart of processing performed by the printer driver when the printer 1 performs printing.
The printer driver receives image data from the application program, converts it into print data in a format that can be interpreted by the printer 1, and outputs the print data to the printer. When converting image data from an application program into print data, the printer driver performs resolution conversion processing, color conversion processing, halftone processing, rasterization processing, command addition processing, and the like. Various processes performed by the printer driver will be described below.

  The resolution conversion process is a process for converting image data (text data, image data, etc.) output from an application program into a resolution (print resolution) for printing on paper. For example, when the print resolution is specified as 720 × 720 dpi, the vector format image data received from the application program is converted into bitmap format image data with a resolution of 720 × 720 dpi. Note that each pixel data of the image data after the resolution conversion process is multi-gradation (for example, 256 gradations) RGB data represented by an RGB color space.

  The color conversion process is a process for converting RGB data into data in a color space corresponding to the ink color forming the image. For example, when printing an image using CMYK ink, RGB data is converted into a CMYK color space. The color conversion processing in this case is performed based on a table (color conversion lookup table LUT) in which the gradation values of RGB data and the gradation values of CMYK data are associated with each other. In this case, the pixel data after the color conversion process is CMYK data of 256 gradations represented by the CMYK color space.

  The halftone process is a process for converting high gradation number data into gradation number data that can be formed by a printer. For example, data representing 256 gradations is converted into 1-bit data representing 2 gradations or 2-bit data representing 4 gradations by halftone processing. In the halftone process, a dither method, a γ correction, an error diffusion method, or the like is used. The data subjected to the halftone process has a resolution equivalent to the print resolution (for example, 720 × 720 dpi). The image data after halftone processing corresponds to 1-bit or 2-bit pixel data for each pixel, and this pixel data is data indicating the dot formation status (presence / absence of dot, dot size) in each pixel. become.

  The rasterizing process rearranges the pixel data arranged in a matrix for each pixel data in the order of data to be transferred to the printer 1. For example, the pixel data is rearranged according to the arrangement order of the nozzles in each nozzle row.

  The command addition process is a process for adding command data (described later) according to the printing method to the rasterized data. Examples of command data include transport data indicating the transport speed of a medium and image quality data indicating image quality.

  The user interface display process includes a process of displaying various user interface windows related to printing on the display device, and a process of receiving user input in these windows.

  The UI printer interface process is a process for taking an interface between the user interface (UI) and the printer 1. Various commands to be transmitted to the printer 1 are generated by interpreting commands instructed by the user through the user interface, and conversely, commands received from the printer 1 are interpreted and displayed on the user interface.

  FIG. 7 is a diagram illustrating an example of a screen displayed on the display device of the computer 110 by the printer driver of the printer 1. Here, an image quality setting screen is displayed in “Printer properties” for performing various settings of the printer driver.

  In this image quality setting screen, the type of image quality is displayed. In the present embodiment, as the type of image quality, it is possible to select a low-gloss texture (hereinafter referred to as matte tone) with reduced surface gloss and a high-gloss texture (hereinafter referred to as gloss tone) with increased surface gloss. ing.

When the user clicks on either the matte tone or the glossy tone on the screen, the printer driver detects this. Then, command data relating to image quality setting (hereinafter referred to as image quality data) is generated by the UI printer interface process, and the image quality data is added to the print data by the command adding process described above.
The print data generated through these processes is transmitted to the printer 1 by the printer driver.

FIG. 8 is a flowchart of the printing process performed by the printer 1 according to the first embodiment.
First, the controller 60 of the printer 1 receives print data from the printer driver (S101). Then, the controller 60 performs an irradiation condition setting process described later according to the image quality data added to the received print data (S102). Thereafter, based on the print data, color dots are formed by ejecting the color inks from the respective color ink heads (S103). Immediately after the dots are formed, from the temporary curing irradiation unit corresponding to each color ink head. Each UV is irradiated to perform temporary curing of the color dots (S104).

After the color dots are formed, the controller 60 discharges (applies) clear ink from the clear ink head to the entire surface of the medium to form clear dots (S105), and then temporarily cures UV from the temporary curing irradiation unit. Irradiation is performed to temporarily cure the clear dots (S106).
Finally, the controller 60 performs main curing of dots on the medium by irradiating UV for main curing from the irradiation unit 44 for main curing (S107).

FIG. 9 is a flowchart of the irradiation condition setting process (S102) of the present embodiment.
The controller 60 determines whether the image quality data received from the printer driver shows a matte tone (S1021). If it is determined that the received image quality data indicates a matte tone (YES in S1021), the controller 60 increases the irradiation energy of the pre-curing irradiation unit 42e corresponding to the clear ink head to more than 15 mJ / cm ² (S1022). ).

On the other hand, when it is determined that the received image quality data does not show a matte tone (NO in S1021), that is, when the received image quality data is a glossy tone, the controller 60 irradiates the temporary curing irradiation unit corresponding to the clear ink head. The irradiation energy of 42e is made smaller than 15 mJ / cm ² (S1023).

  10A and 10B are conceptual diagrams of printed matter according to the first embodiment. 10A is a conceptual diagram when the matte tone is set, and FIG. 10B is a conceptual diagram when the glossy tone is set.

When the user selects a matte tone, the UV irradiation energy for pre-curing the clear ink applied on the color image is set to be larger than 15 mJ / cm ² (for example, 30 mJ / cm ² ). In this case, as shown in FIG. 10A, the unevenness of the surface shape of the coating layer by the clear ink becomes large, resulting in a low gloss image.

In addition, when the user selects a glossy tone, the UV irradiation energy for pre-curing the clear ink applied on the color image is set to be smaller than 15 mJ / cm ² (for example, 5 mJ / cm ² ). In this case, as shown in FIG. 10B, the surface shape of the coating layer made of clear ink becomes smooth, resulting in a highly glossy image.

  As described above, in the printer 1 of the present embodiment, the provisional curing UV irradiation from the provisional curing irradiation unit 42e corresponding to the clear ink head according to the image quality (texture) setting by the user in the user interface. I try to change my energy. In this way, the texture of the image can be easily adjusted without changing the type of the medium.

  In addition, since the elastic UV ink is used as the clear ink for coating the surface, the surface of the image can be more reliably protected as compared with the comparative example.

  In this embodiment, since the UV ink is also used as the color ink, an image can be printed satisfactorily even on a medium that hardly absorbs liquid. In the present embodiment, the provisional curing irradiation portions 42a to 42d are provided corresponding to the respective color ink heads. However, the provisional curing corresponding to the most downstream head in the transport direction among the color ink heads. Only the irradiation unit (in the case of FIG. 2, the temporary curing irradiation unit 42d corresponding to the yellow ink head Y) may be used. Then, provisional curing may be performed after the color image is formed.

  Furthermore, if it is possible to reversely convey the medium, only the temporary curing irradiation section 42e may be used. In this case, after the image is printed on the medium by the color ink head, the color image is temporarily cured by irradiating the temporary curing UV from the temporary curing irradiation unit 42e without applying the clear ink. Then, the medium is returned to the front side of the clear ink head by reversely conveying the medium, and then the clear ink is applied to the entire surface by normal conveyance, and the temporary curing UV is irradiated from the temporary curing irradiation unit 42e. You can do it.

=== Second Embodiment ===
In the first embodiment, UV ink is used for each of the color ink for printing an image and the clear ink for coating the surface. In this case, as shown in FIGS. 10A and 10B, a step of, for example, about 10 μm occurs between a portion where an image is formed and a portion where an image is not formed. Further, a step is also generated between the dark image and the light image. For this reason, even if the clear ink is temporarily cured under the same conditions, the gloss may not be uniform depending on the image to be printed.
Therefore, in the second embodiment, water-based ink is used as color ink, and UV ink is used only for clear ink for coating the surface.

FIG. 11 is a schematic view of the periphery of the print area in the second embodiment.
In the printer 1 of the second embodiment, the color ink heads (black ink head K, cyan ink head C, magenta ink head M, and yellow ink head Y) each discharge aqueous ink (color ink).
Compared with FIG. 2, since the ink ejected from the color ink head is water-based ink, the provisional curing irradiation portions 42 a to 42 d are not provided.

FIG. 12 is a flowchart of the printing process performed by the printer 1 according to the second embodiment.
Steps S201 and S202 in FIG. 12 are the same as steps S101 and S102 in FIG.
In the second embodiment, after the irradiation condition setting process (S202), the controller 60 discharges aqueous color ink from each color ink head based on the print data to form color dots (S203).
Then, the controller 60 discharges (applies) clear ink from the clear ink head to the entire surface of the medium to form clear dots (S204), and then irradiates the pre-curing irradiation section with the pre-curing UV. The dots are temporarily cured (S205).
Finally, the controller 60 performs main curing of the dots on the medium by irradiating UV for main curing from the irradiation unit 44 for main curing (S206).

  13A and 13B are conceptual diagrams of printed matter according to the second embodiment. 13A is a conceptual diagram when the matte tone is set, and FIG. 13B is a conceptual diagram when the glossy tone is set.

Similar to the first embodiment, when the user selects a matte tone, the UV irradiation energy for pre-curing the clear ink applied on the color image is greater than 15 mJ / cm ² (for example, 30 mJ / cm ^2). Set). In this case, as shown in FIG. 13A, the unevenness of the surface shape of the coating layer by the clear ink becomes large, resulting in a low gloss image.
In addition, when the user selects a glossy tone, the UV irradiation energy for pre-curing the clear ink applied on the color image is set to be smaller than 15 mJ / cm ² (for example, 5 mJ / cm ² ). In this case, as shown in FIG. 13B, the surface shape of the coating layer made of clear ink becomes smooth, resulting in a highly glossy image.

In the second embodiment, since the water-based ink is used as the color ink, the color image can be formed thinly. Therefore, as compared with the first embodiment (see FIGS. 10A and 10B), a step due to the presence or absence of a color image can be reduced, and coating can be performed on a flat medium. As a result, the texture can be adjusted regardless of the image to be printed (the presence or absence of the image or the density of the image). Therefore, the gloss can be made more uniform.
Further, by using water-based ink as the color ink, it is possible to widen the range of colors (gamut) that can be expressed as compared with the case of using UV ink.

=== Third Embodiment ===
In the embodiment described above, the color image printing process and the clear ink coating process are performed by the printer 1, but in the third embodiment, only the clear ink coating process is performed.
FIG. 14 is a schematic view of the periphery of the print area in the third embodiment. In the figure, parts having the same configuration as in FIG.
The printer 1 according to the third embodiment includes a clear ink head CL that discharges clear ink, a provisional curing irradiation unit 42e, and a main curing irradiation unit 44.

FIG. 15 is a flowchart of print processing by the printer 1 according to the third embodiment.
First, the controller 60 receives print data from the printer driver (S301). However, the print data received in the third embodiment does not include data for printing a color image. Then, the controller 60 performs irradiation condition setting processing according to the image quality data added to the print data (S302). Note that this irradiation condition setting process is the same as the above-described FIG. 9 (S102 in FIG. 8 and S202 in FIG. 12), and thus description thereof is omitted.

  Then, the controller 60 discharges (applies) clear ink from the clear ink head to the entire surface of the medium while the medium is being transported to form clear dots (S303). Thereafter, provisional curing UV is irradiated from the temporary curing irradiation unit 42e to perform temporary curing of the clear dots (S304), and finally the main curing UV is irradiated from the main curing irradiation unit 44 to perform the main curing. This is performed (S305).

  As described above, the surface texture can be adjusted by applying the clear ink to the medium on which the image (color image) has already been printed and changing the energy of the UV irradiation for temporary curing.

=== Other Embodiments ===
Although a printer or the like as one embodiment has been described, the above embodiment is for facilitating the understanding of the present invention, and is not intended to limit the present invention. The present invention can be changed and improved without departing from the gist thereof, and it is needless to say that the present invention includes equivalents thereof. In particular, the embodiments described below are also included in the present invention.

<About the printer>
In the above-described embodiment, the printer has been described as an example of the liquid ejection apparatus, but the present invention is not limited to this. For example, color filter manufacturing apparatus, dyeing apparatus, fine processing apparatus, semiconductor manufacturing apparatus, surface processing apparatus, three-dimensional modeling machine, liquid vaporizer, organic EL manufacturing apparatus (particularly polymer EL manufacturing apparatus), display manufacturing apparatus, film formation The same technology as that of the present embodiment may be applied to various liquid ejection devices to which inkjet technology such as a device and a DNA chip manufacturing device is applied.

  Moreover, although it was a line printer in the above-mentioned embodiment, it is not restricted to this. For example, a printer in which a plurality of heads and a plurality of provisional curing irradiation units are alternately provided facing the peripheral surface of a cylindrical conveyance drum, and a main curing irradiation unit is provided on the most downstream side in the conveyance direction. May be.

<About ink>
In the above-described embodiment, ink (UV ink) that is cured by being irradiated with ultraviolet rays (UV) is ejected from the nozzles. However, the liquid ejected from the nozzle is not limited to such ink, and a liquid that is cured by irradiation with light other than UV (for example, visible light) may be ejected from the nozzle. In this case, light (such as visible light) for curing the liquid may be irradiated from the temporary curing irradiation unit and the main curing irradiation unit.

<About the printer driver>
The printer driver processing described above may be performed on the printer side. In that case, the liquid ejection apparatus is configured by the printer and the PC on which the printer driver is installed.

<About clear ink>
In the embodiment described above, the colorless and transparent clear ink is used to form dots other than the image. However, the present invention is not limited to the clear ink. For example, it may be a translucent processing liquid that gives the surface of the medium gloss.

<About image quality settings>
In the embodiment described above, there are two types of image quality settings, matte tone and glossy tone. However, the present invention is not limited to this, and two or more types may be used. In this case, the UV irradiation energy from the temporary curing irradiation unit corresponding to the clear ink head may be changed according to the image quality. For example, the UV irradiation energy may be reduced as the gloss is increased.

1 printer, 20 transport unit,
23A upstream conveyance roller, 23B downstream conveyance roller,
24 belts, 30 head units, 40 irradiation units,
42a-42e irradiation part for temporary curing, 44 irradiation part for main curing,
50 detector groups, 60 controllers, 61 interface units,
62 CPU, 63 memory, 64 unit control circuit,
110 computers,
K black ink head, C cyan ink head, M magenta ink head,
Y yellow ink head, CL clear ink head

Claims (6)

A working fluid for processing the surface of the medium, a working fluid nozzle that discharges to the medium a working fluid that cures when irradiated with light,
A color nozzle for discharging a color liquid;
A transport unit that transports the medium in a transport direction and in a direction opposite to the transport direction;
A first irradiation unit for irradiating the light;
After the color liquid is ejected from the color nozzle onto the medium to form a color image, the medium is transported in the opposite direction, and the machining liquid is ejected from the machining liquid nozzle onto the color image. A controller for irradiating the processing liquid with the light from the first irradiation unit ,
The controller changes the irradiation energy of light from the first irradiation unit according to the texture setting.
A liquid discharge apparatus characterized by that. The liquid ejection device according to claim 1,
The irradiation energy of light emitted from the first irradiation unit is irradiated from the first irradiating unit if the previous Kishitsu sense is set to glossy if the previous Kishitsu sense is set to matte Greater than the irradiation energy of light ,
A liquid discharge apparatus characterized by that. The liquid ejection device according to claim 2,
Irradiation energy of light before Kishitsu feeling is irradiated from the first irradiating unit when it is set to matte is ^{15mJ / cm 2 ~30mJ / cm 2} ,
Irradiation energy of light before Kishitsu feeling is irradiated from the first irradiating unit when it is set to glossy is ^{5mJ / cm 2 ~15mJ / cm 2} ,
A liquid discharge apparatus characterized by that. The liquid ejection device according to any one of claims 1 to 3,
A second irradiation unit that irradiates the processing liquid irradiated with light from the first irradiation unit with the light;
A liquid discharge apparatus characterized by that. A liquid ejection apparatus according to any one of claims 1 to 4 ,
The color liquid is a liquid that hardens when irradiated with light ,
The controller ejects the color liquid from the color nozzle onto the medium to form the color image, and then transports the medium in the transport direction, and the light is applied to the color image from the first irradiation unit. Irradiating and transporting the medium in the reverse direction after irradiating the light from the first irradiation unit,
A liquid discharge apparatus characterized by that. A liquid ejection apparatus according to any one of claims 1 to 4 ,
The liquid discharge apparatus according to claim 1, wherein the color liquid is an aqueous liquid.

Images