JP2016147394A - Image formation apparatus, method of manufacturing recording material and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image formation apparatus in which printing quality is improved by easily and inexpensively suppressing image irregularity at the time of bidirectional printing.SOLUTION: An image formation apparatus comprises: a recording head including a plurality of liquid droplet discharge heads (24) discharging active energy-ray curable ink to a recording medium; a carriage (23) which mounts the recording head and moves in the main scanning direction; a plurality of irradiation units (51, 52) which are arranged on both sides of the recording head in the main scanning direction and irradiate the active energy-ray curable ink discharged to the recording medium with the active energy ray; and a decision unit which decides the liquid droplet discharge head discharging the active energy-ray curable ink on the basis of input image data. The distances between the decided liquid droplet discharge head and the respective irradiation units become equal.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an image forming apparatus, a recorded product manufacturing method, and a control program.

  As an image forming apparatus, for example, an ink jet recording apparatus is known as an image forming apparatus of a liquid discharge recording method using a recording head composed of a liquid discharge head (droplet discharge head) for discharging droplets.

  As such an image forming apparatus, in order to form a three-dimensional image or increase the image density, an active energy ray curable liquid such as an ultraviolet curable ink is used, and the liquid layers are laminated while being sequentially cured. Some of them form images. Here, after the ultraviolet curable ink is ejected, it is cured by irradiating with ultraviolet rays to form an image.

  Here, in order to shorten the printing time for stacking and printing, bidirectional color unevenness and speed with constant UV irradiation time after ink is ejected in the forward and return paths during bidirectional printing. The technology which balances is known. For example, in Patent Document 1, a UV lamp is arranged in the center, and each ink head is arranged symmetrically with respect to the UV lamp.

  However, when the UV lamp is arranged in the center and the heads are arranged symmetrically, there is a problem that the distance between the heads of the same color becomes long and the landing position is liable to shift. In addition, the head is relatively expensive, and there is a problem that the cost is high if the heads are arranged symmetrically.

In addition, bi-directional printing is performed for the purpose of shortening the printing time. However, since the distance between the recording head and the UV lamp is different between the forward path and the backward path, the time required for ultraviolet irradiation differs between the forward path and the backward path. There is a problem that the height of the printed dots is uneven and the image quality is lowered.
In view of the above, there is a demand for a technique that can easily form a high-quality image while being inexpensive and preventing unevenness during bidirectional printing.

  In view of the above problems, an object of the present invention is to provide an image forming apparatus that can easily and inexpensively suppress image unevenness during bidirectional printing and improve print quality.

  In order to solve the above problems, an image forming apparatus of the present invention includes a recording head including a plurality of droplet discharge heads that discharge active energy ray-curable ink to a recording medium, and the recording head. A carriage that moves in the scanning direction; and a plurality of irradiation units that are arranged on both sides of the recording head in the main scanning direction and that irradiate the active energy ray-curable ink discharged to the recording medium with active energy rays. A determination unit that determines a droplet discharge head that discharges the active energy ray-curable ink based on the obtained image data, and each of the determined droplet discharge head and each of the plurality of irradiation units It is characterized by equal distances.

  According to the present invention, it is possible to provide an image forming apparatus that can easily and inexpensively suppress image unevenness during bidirectional printing and improve print quality.

1 is a schematic diagram illustrating an example of an image forming apparatus according to the present invention. FIG. 3 is a schematic diagram illustrating an example of an image forming unit of the image forming apparatus according to the present invention. 1 is a schematic diagram illustrating a main part in an example of an image forming apparatus according to the present invention. It is a figure which shows an example of the hardware constitutions of the main control part in the image processing apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image formation part of the image forming apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image formation part of the image forming apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image formation part of the image forming apparatus which concerns on this invention. It is a schematic diagram which shows the other example of the image formation part of the image forming apparatus which concerns on this invention. It is a figure which shows the relationship between dot height and the time from ink landing to UV irradiation. FIG. 3 is a schematic diagram illustrating an example of a cross section of ink in a forward path and a return path of a recording head. FIG. 6 is a schematic diagram illustrating another example of a cross section of ink in a forward path and a return path of a recording head. FIG. 6 is a schematic diagram illustrating another example of a cross section of ink in a forward path and a return path of a recording head.

  Hereinafter, an image forming apparatus, a method for manufacturing recorded matter, and a control program according to the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments described below, and other embodiments, additions, modifications, deletions, and the like can be changed within a range that can be conceived by those skilled in the art, and any aspect is possible. As long as the functions and effects of the present invention are exhibited, the scope of the present invention is included.

(First embodiment)
Hereinafter, an embodiment of an image forming apparatus according to the present invention will be described.
An image forming apparatus according to the present embodiment includes a recording head including a plurality of droplet discharge heads that discharge active energy ray-curable ink to a recording medium, and a carriage that mounts the recording head and moves in the main scanning direction. A plurality of irradiation units that are arranged on both sides of the recording head in the main scanning direction and irradiate the active energy ray-curable ink discharged to the recording medium with active energy rays, and based on input image data A determination unit that determines a droplet discharge head that discharges the active energy ray-curable ink, and the distances between the determined droplet discharge head and the plurality of irradiation units are equal to each other. Features.

  An image forming apparatus according to this embodiment will be described with reference to FIGS. FIG. 1 is a diagram schematically illustrating the image forming apparatus, and is a diagram schematically illustrating a cross section of the image forming apparatus. FIG. 2 is a diagram schematically showing the main part of FIG. 1 as viewed from above. In FIG. 2, the “apparatus rear side (rear side)” corresponds to the back side of the paper in FIG. 1, and the “apparatus front side (front side)” corresponds to the front side of the paper in FIG.

  FIG. 2 shows a state in which the distances between the droplet discharge head for discharging droplets and the plurality of irradiation units are not equal, but are included in the image forming apparatus of the present invention. . As will be described in detail later, the image forming apparatus shown in FIG. 2 can equalize the distances between a droplet discharge head that discharges droplets and a plurality of irradiation units.

  FIG. 1 illustrates an image forming unit 2, a sub-transport unit 3, and a supply unit 4. The recording medium 14 is transported along transport paths 310, 305, and 306 and discharged onto the paper discharge tray 104. In the conveyance path 305, the recording medium 14 is conveyed by the conveyance belt 13 and an image is formed by the image forming unit 2 having the guide rod 21, the carriage 23, the recording head 24, and the like.

  The image forming apparatus 1 includes, as the image forming unit 2, a carriage 23 equipped with a recording head 24 including a plurality of liquid droplet ejection heads that eject ink droplets (ink droplets) that are cured by irradiation with active energy rays. ing. Examples of the active energy rays include ultraviolet rays and electron beams, among which ultraviolet rays are preferable.

As shown in FIG. 2, the scanning direction of the carriage 23 is the main scanning direction, and the main scanning direction is a direction orthogonal to the conveyance direction of the paper 5 (recording medium 14). The carriage 23 includes a plurality of irradiation units (UV lamps 51 and 52) that are arranged on both sides of the recording head 24 in the main scanning direction and irradiate the active energy ray-curable ink ejected from the recording head 24 with active energy rays. ing. In the following description, an ultraviolet lamp unit (UV lamp) is used as the irradiation unit and ultraviolet rays are used as the active energy rays. However, the present invention is not limited to this.
The ink droplets ejected onto the recording medium 14 by the UV lamps 51 and 52 are irradiated with ultraviolet rays, whereby the ink droplets are cured and fixed on the recording medium 14.

The image forming apparatus 1 includes an image forming unit 2 for forming an image, a sub-scanning conveying unit 3 and the like inside the apparatus main body (housing). The recording medium 14 is fed one by one from the paper feeding unit 4 provided on the right side surface of the apparatus main body, and is conveyed to the conveyance path 305 of the sub-scanning conveyance unit 3 via the conveyance path 310. Ink is ejected by the image forming unit 2 while the recording medium 14 is transported by the sub-scanning transport unit 3, and a desired image is formed (recorded) by forming the required number of layers. Thereafter, the recorded matter (the recording medium 14 on which the image is formed) is discharged onto a discharge tray 104 provided on the left side surface portion of the apparatus main body through the conveyance path 306.
Although details will be described later, the present invention is preferably applied when an image is formed by laminating.

Here, the “number of layers” indicates the number of times the image is stacked when one image is formed and then the next layer is formed on the image.
When forming the second and subsequent layers, the recording medium 14 is first transported in the order of the transport paths 306, 305, and 310 and then returned to the transport path 310. An image is formed on the recording medium 14 returned to the conveyance path 310 by the above-described image forming procedure. By repeating this, a required image is formed by forming the required number of layers, and the paper is discharged onto the paper discharge tray 104.

  Here, as shown in FIG. 2, the image forming unit 2 of the image forming apparatus 1 uses a guide rod 21 and a guide stay to move a carriage 23 in which droplet discharge heads for each color are arranged in the main scanning direction. Holds movable. The carriage 23 is moved and scanned in the main scanning direction by a main scanning motor 27 via a timing belt 29 spanned between the driving pulley 28A and the driven pulley 28B.

Further, the UV lamps 51 and 52 are locked on both sides (upper and lower sides in the figure) of the carriage 23 by ball screw rods 53 and 54 that are spirally threaded. It is arranged to be able to move to. That is, the UV lamps 51 and 52 receive the ball screw rods 53 and 54 with a ball screw (not shown), and the ball screw rods 53 and 54 are rotated by a motor (not shown) provided on the carriage 23 so that the carriage 23 On the other hand, it can move up and down.
The carriage 23 can adjust the distance in the vertical direction between the recording head 24 and the recording medium 14 according to the number of layers of the target image, that is, according to the thickness of the ink.

  The UV lamps 51 and 52 are moved and scanned in the main scanning direction together with the carriage 23 at a predetermined distance. On the carriage 23, a recording head 24 comprising a plurality of droplet discharge heads for discharging droplets of the respective colors is mounted. The carriage 23 is moved in the main scanning direction, and droplets are ejected from the recording head 24 while the recording medium 14 is fed in the paper conveyance direction (sub scanning direction) by the sub scanning conveyance unit 3. At the same time, it is a shuttle type in which the ink is cured while irradiating ultraviolet rays with the UV lamps 51 and 52 to form an image.

  The recording head 24 in this embodiment discharges a droplet discharge head 24k that discharges black (Bk) ink, and discharges white (W) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink. Each of the two droplet discharge heads 24w, 24c, 24m, and 24y includes a total of five droplet discharge heads. Ink of each color is supplied from each sub tank 25 mounted on the carriage 23. The color and number of inks are not limited to this, and can be changed as necessary.

  On the other hand, as shown in FIG. 1, for example, black (Bk) ink, white (W) ink, cyan (C) ink, magenta (M) ink, yellow from the front surface (front side of the paper) of the apparatus main body to the cartridge mounting portion. (Y) Each color ink cartridge 26 which is a recording liquid cartridge containing ink can be detachably mounted. In this case, ink is supplied from each color ink cartridge 26 (26k, 26w, 26c, 26m, 26y, “ink cartridge 26” when not distinguished) to the sub tank 25 of each color. Note that the ink cartridge 26 shown in FIG. 1 is schematically shown, and the size ratio between the cartridge mounting portion and the sub tank 25 is different from the actual one.

  As the recording head 24, as a pressure generating means (actuator means) for pressurizing ink in the ink flow path (pressure generating chamber), a piezoelectric plate is used to deform a diaphragm that forms the wall surface of the ink flow path, thereby causing the ink flow path. An example is a so-called piezo type that ejects ink droplets by changing the internal volume. In addition, the diaphragm and electrode that form the wall surface of the ink flow path are placed facing each other, and the diaphragm is deformed by the electrostatic force generated between the vibration plate and the electrode, thereby changing the volume of the ink flow path. For example, an electrostatic type that discharges ink droplets can be used. However, the droplet discharging means is not limited to such an exemplified method.

  As shown in FIG. 2, a maintenance / recovery mechanism 121 for maintaining and recovering the state of the nozzles of the recording head 24 can be disposed in a non-printing area on one side of the carriage 23 in the scanning direction. The maintenance / recovery mechanism 121 wipes the nozzle surfaces of the droplet discharge heads and the moisturizing cap 122 (122y, 122m, 122k, 122w, 122c) for capping the nozzle surfaces of the five droplet discharge heads. A wiper member 124, an empty discharge receiving member 125 for discharging droplets (empty discharge) that do not contribute to recording (image formation), and the like.

Further, the non-printing area on the other side in the scanning direction of the carriage 23 is provided with a blank discharge receiving member 126 for discharging droplets (empty discharge) that does not contribute to recording (image formation) from the droplet discharge head. Yes. The empty discharge receiving member 126 has five openings 127 (127y, 127m, 127k, 127w, 127c) corresponding to the five droplet discharge heads.
If necessary, a maintenance unit that performs maintenance of each head of the carriage 23 may be provided. In this case, you may provide the waste liquid tank which collect | recovers the waste liquid discharged | emitted after a maintenance.

Next, the transport mechanism will be described with reference to FIG. FIG. 3 shows a main part of the image forming apparatus 1 of FIG.
The sub-scanning conveyance unit 3 shown in FIG. 3 has a conveyance belt 13 for sucking the recording medium 14 and conveying it to the image forming unit 2. The conveyor belt 13 is wound around the conveyor roller 19 and the driven roller 21 and is tensioned by the tension roller 15 so as to maintain an appropriate tension.

  The tension roller 15 is held by an arm 37b, and the arm 37b is disposed so as to be capable of rotational movement with the rotation fulcrum 37a as a fulcrum. Therefore, for example, the tension roller 15 can move in the direction of the arrow shown in FIG. 3, and the tension of the conveyor belt 13 is adjusted.

  Further, the position of the driven roller 21 can be changed, and the conveying surface formed by the conveying roller 19 and the driven roller 21 can be lowered by a distance a shown in FIG. 3, for example.

A platen member 22 for guiding the conveying belt 13 in a region facing the image forming unit 2 and maintaining appropriate flatness is disposed.
The conveyor belt 13 includes, for example, a surface layer that is a sheet adsorbing surface formed of a pure resin material that is not subjected to resistance control, such as ETFE pure material, and a back layer that is subjected to resistance control using carbon with the same material as the surface layer. It is preferable to have a two-layer structure (medium resistance layer, earth layer), but this is not restrictive, and a one-layer structure or a structure of three or more layers may be used.

A pressure roller 38 that presses the recording medium 14 against the conveyance belt 13 at a position facing the conveyance roller 19 is disposed on the upstream side of the conveyance mechanism. The pressure roller 38 is pressed and brought into close contact, and the recording medium 14 is attracted to the transport belt 13 by static electricity.
Further, in order to charge the surface of the conveyor belt 13, in the circumferential direction of the conveyor belt 13, on the upstream side of the pressure roller 38, a high-voltage power supply (DC or a superimposed bias supply unit of DC and AC) is changed to a direct voltage or a direct current. A charging roller 18 to which a high voltage on which alternating current is superimposed is supplied is disposed.

  On the other hand, on the downstream side of the transport mechanism, a discharge roller 16 that transports the recording medium 14, a discharge roller 17 that presses the recording medium 14, and the discharged medium 14 are stocked. A paper discharge mechanism including a paper discharge tray 104 is disposed.

  An operation panel that displays the state of the image forming apparatus and can operate the image forming apparatus may also be provided.

<Overview of control unit>
Next, an outline of the control unit of this apparatus will be described with reference to FIG. FIG. 4 is a block diagram of the control unit.

  The control unit 200 includes a CPU 201 that controls the entire apparatus, a ROM 202 that stores programs executed by the CPU 201, drive waveform data, and other fixed data, and a RAM 203 that temporarily stores image data and the like. In addition, a non-volatile memory (NVRAM) 204 for holding data while the apparatus is powered off, image processing for performing various signal processing and rearrangement on image data, and other control for the entire apparatus And an ASIC 205 for processing input / output signals.

The control unit 200 includes an I / F 207 for transmitting and receiving data and signals to and from an external device, and a head drive control unit 208 and a head driver 209 for driving and controlling the recording head 24 of the image forming unit 2. I have. Further, a main scanning motor 27 for main scanning the carriage 23, a sub scanning motor 131 for rotating the conveying roller 19 by rotating the conveying roller 19, a paper feeding motor 45, a paper discharging motor 271, a double-sided conveying motor 291, a recording medium Motor driving units 211 to 215 and 317 for driving a transport motor 318 that transports 14.
In addition, a lamp unit drive control unit for controlling the lighting of the UV lamps 51 and 52 is provided.

  Further, detection signals from sensors such as an encoder that outputs a detection signal corresponding to the moving amount and moving speed of the conveyor belt 13 and a temperature / humidity sensor 300 that detects environmental temperature and environmental humidity (whichever may be used) are provided. An input I / O 221 is provided. The control unit 200 is connected to an operation panel 222 for inputting and displaying information necessary for the apparatus.

  The control unit 200 receives print data and the like from the host side such as an information processing device such as a personal computer, an image reading device such as an image scanner, and an imaging device such as a digital camera via the cable or the network by the I / F 207. Note that the reading device may be, for example, the image reading unit 11 controlled by the scanner control unit 206.

  Then, the CPU 201 reads and analyzes the print data in the reception buffer included in the I / F 207, performs necessary image processing, data rearrangement processing, and the like by the ASIC 205, and reduces the head width of the recording head 24 to one page. Corresponding image data (dot pattern data) is sent to the head drive controller 208 in synchronization with the clock signal.

  When the head drive control unit 208 receives image data (dot pattern data) corresponding to one row of the recording head 24, the head drive control unit 208 transfers the dot pattern data for one row to the head driver 209. The head driver 209 selectively drives the actuator means of the recording head 24 by applying a required driving waveform based on the dot pattern data, and discharges droplets from the nozzles of the required droplet discharge head in the recording head 24. Let

  The head drive control unit 208 transfers a droplet detection command issued from the CPU 201 to a droplet detection control unit (not shown), and the droplet detection control unit controls the droplet detection device according to the timing of the command. The droplet detection device detects a discharge state of a droplet from a droplet discharge head through a light emitting unit which is a light emitting unit, a light receiving unit which is a light receiving unit, and an optical axis deflecting device, and detects detection data obtained based on the detection result. The data is transferred to the CPU 201 via the droplet detection control unit.

  CPU201 transmits irradiation data to a lamp unit drive control part based on detection data. Based on this, the lamp unit drive control unit controls the UV lamps 51 and 52, and the UV lamps 51 and 52 irradiate ultraviolet curable ink (active energy ray curable ink) discharged from the droplet discharge head. As a result, an image is formed (recorded).

  In the image forming apparatus configured as described above, as described above, the recording medium 14 is fed one by one from the sheet feeding unit 4 and is pressed against the transport belt 13 by the pressure roller 38 and transported. Then, the recording medium 14 is electrostatically attracted to the conveyance belt 13, and the recording medium 14 is conveyed in the sub-scanning direction by the circumferential movement of the conveyance belt 13.

Therefore, by driving the recording head 24 based on the image signal while moving the carriage 23, ink droplets are ejected onto the recording medium 14 that has been stopped to record one line. When recording for one line is completed, the recording medium 14 is transported by one line, and the recording medium 14 is intermittently conveyed so that an image is formed. Can do.
When the recording end signal or the signal that the rear end of the recording medium 14 reaches the recording area is received, the recording operation is ended. The recording medium 14 on which the image is formed is sent out to a paper discharge tray 104 which is a transport destination.

  In the above-described embodiment, an example in which a conveyance belt that performs electrostatic adsorption is used as the conveyance unit has been described. However, a conveyance belt that performs adsorption by a suction fan can also be used. Further, it is possible to adopt a configuration in which a sheet is conveyed opposite to the image forming unit by a conveyance roller and a pressure roller without using a conveyance belt.

<Image forming method>
Next, an image forming method according to the present embodiment will be described with reference to FIGS. 5 to 8 are schematic explanatory views of the image forming unit.
FIG. 9 is a diagram showing the relationship between the dot height of ink droplets and the time from ink landing to UV irradiation, and FIGS. 10 to 12 are schematic diagrams of image cross sections of the ink droplets 8 formed on the recording medium 14. It is.

  First, bidirectional printing unevenness (hereinafter referred to as “bidirectional unevenness”), which is a problem in the prior art, will be described with reference to FIGS. 9 and 10. FIG. 9 shows the relationship between the dot height when the ejection amount of one droplet ejected from one nozzle in the recording head 24 is 14 pl and 5 pl, and the time from ink landing to UV irradiation. Since the spread of ink droplets on the recording medium 14 varies depending on the time from ink landing to UV irradiation (because it spreads over time), the ink height changes as shown in FIG.

  For this reason, if the distance between the UV lamp and the droplet discharge head is different between the forward path and the backward path, the dot height becomes as shown in FIG. 10 and image unevenness occurs. FIG. 10 shows the positions of the UV lamps 51 and 52 in FIG. 2, and the forward path ((A) / (C), movement from the lower side to the upper side in FIG. 2) and the return path ((B), FIG. 2, etc.). FIG. 6 is a schematic diagram of a cross section of an image when, for example, black ink is printed in a movement from the upper side to the lower side in FIG. As shown in FIG. 10, the dot height and the dot area differ between the forward path (A) / (C) and the backward path (B) of the recording head, resulting in image unevenness.

  On the other hand, in the present embodiment, bidirectional unevenness is prevented by making the distances between the droplet discharge heads that discharge ink in the forward path and the backward path and the UV lamps 51 and 52 the same. That is, the distances between the droplet discharge head determined by the determination unit and the plurality of irradiation units are equal.

  In the present embodiment, in the recording head, a droplet discharge head that discharges black ink is disposed at the center in the main scanning direction. As shown in FIG. 5, a droplet discharge head 24k that discharges black (Bk) ink is disposed at the center of the carriage. As a result, the distance between the black ink droplet discharge head 24k and the UV lamps 51 and 52 is the same (both are distance X2), and the black ink bidirectional unevenness is eliminated. For example, when only black ink that needs to be shielded from backlight, such as a meter panel, is printed in multiple layers, such a configuration eliminates bidirectional unevenness.

(Second Embodiment)
Next, another embodiment of the image forming apparatus according to the present invention will be described. In addition, the description about the same point as the said embodiment is abbreviate | omitted.

In the present embodiment, in the recording head, a droplet discharge head for discharging white active energy ray-curable ink is disposed in the center in the main scanning direction.
In the present embodiment, a droplet discharge head 24w that discharges white ink is disposed at the position of the droplet discharge head 24k that discharges black ink shown in FIG.

  The black ink described above is frequently used for light shielding, and the white ink is also frequently used because it is a base for color printing. That is, black ink and white ink are often used in a single color. For example, white ink is known to be used in a single color as a color base in order to improve color developability. When light shielding properties are required, multilayer coating is preferable. According to the present embodiment, it is possible to improve print quality by suppressing image unevenness for white ink as well.

(Third embodiment)
Next, another embodiment of the image forming apparatus according to the present invention will be described. In addition, the description about the same point as the said embodiment is abbreviate | omitted.
In this embodiment, the position of the UV lamp or the position of the recording head is controlled based on the droplet discharge head to be used. The image forming apparatus according to the present embodiment is based on the drive unit that relatively moves the recording head 24 and the UV lamps 51 and 52 (irradiation unit), and the droplet discharge head determined by the determination unit. And a control unit that controls the driving unit. The control unit controls the driving unit so that the distances between the determined droplet discharge head and the UV lamps 51 and 52 are equal.

  A diagram for explaining the present embodiment is shown in FIG. FIG. 5 shows an example in which a droplet discharge head that discharges black ink is selected, but FIG. 6 shows an example in which a droplet discharge head 24y that discharges yellow (Y) ink is selected. Indicates. In FIG. 6, the position is adjusted so that the distance between the droplet discharge head 24 y and the UV lamp 51 is equal to the distance between the droplet discharge head 24 y and the UV lamp 52.

  In the example shown in FIG. 6, the positions of the UV lamps 51 and 52 in FIG. 5 can be changed by the driving unit to the position shown in FIG. 6. That is, the distance between the droplet discharge head 24y and the UV lamp 51 is X1, and the distance between the droplet discharge head 24y and the UV lamp 52 is X1, and both are equal. Thereby, the irradiation time of the UV lamp is equal in the forward path and the backward path of the recording head, the height and area of the dots can be equalized, and image unevenness can be suppressed.

  An example in which cyan (C) ink is ejected is shown in FIG. In this case, similarly to the yellow ink, the distance between the droplet discharge head 24c and the UV lamp 51 is X1, and the distance between the droplet discharge head 24c and the UV lamp 52 is X1, and both are equal. Therefore, image unevenness can be suppressed. Further, in any ink, bidirectional unevenness due to a difference in dot height generated due to a time difference from ink landing to UV irradiation during bidirectional printing can be easily eliminated.

  The timing at which the drive unit moves the recording head and / or the UV lamp is not particularly limited and can be changed as appropriate. For example, the position may be adjusted before the recording medium 14 reaches the image forming unit 2 or may be in the middle of forming an image. For this reason, after the carriage 23 reciprocates several times, the position is adjusted by the drive unit, and the carriage 23 can be reciprocated again to form an image.

(Fourth embodiment)
Next, another embodiment of the image forming apparatus according to the present invention will be described. In addition, the description about the same point as the said embodiment is abbreviate | omitted.
In the present embodiment, the drive unit controls the recording head 24 so that the distance between the determined droplet discharge head and the UV lamps 51 and 52 is equal and the distance can be arbitrarily changed. Thus, the UV lamps 51 and 52 are moved.

  This embodiment will be described with reference to FIG. 8 is the same as FIG. 5 in that the droplet discharge head 24k that discharges black ink is arranged at the center of the recording head 24 in the main scanning direction. This embodiment is different in that the distance between the droplet discharge head 24k and the UV lamps 51 and 52 can be arbitrarily set. That is, the distance X2 in FIG. 5 is changed to the distance X3.

  For example, when black is bidirectionally printed at the position shown in FIG. 5, an image cross section as shown in FIG. 11 is obtained, and when black is bidirectionally printed at the position shown in FIG. 8, an image cross section is obtained as shown in FIG. At the position of FIG. 5, the dot height is relatively high as shown in FIG. 11, so the image has a low glossiness. Conversely, at the position of FIG. 8, the dot height is compared as shown in FIG. Therefore, an image with high glossiness is obtained.

  As a result, bidirectional unevenness can be eliminated and the gloss of the image can be controlled. That is, the state of the ink surface layer can be controlled. In addition, the state of the ink surface layer is not limited to glossiness control. For example, when ink is further laminated on the ink layer, the lower layer is controlled smoothly so that the lower layer image is compared to the uppermost layer image. It is also possible to prevent the unevenness from affecting.

  Therefore, according to this embodiment, in addition to the suppression of bidirectional unevenness due to the difference in dot height that occurs due to the time difference from ink landing to UV irradiation during bidirectional printing, the surface layer shape of the ink can also be easily controlled. . For these reasons, the present invention is also suitably applied to the case where the active energy ray curable ink is laminated on the recording medium 14.

  In the present embodiment, the aspect in which the control unit adjusts the positions of the UV lamps 51 and 52 with respect to the recording head 24 has been described. However, the present invention is not limited to this, and the aspect in which the position of the recording head 24 is adjusted. There may be. The drive unit only needs to move the recording head and the irradiation unit relatively.

(Fifth embodiment)
Next, another embodiment of the image forming apparatus according to the present invention will be described. In addition, the description about the same point as the said embodiment is abbreviate | omitted.
The image forming apparatus according to the present embodiment includes a recording head including a plurality of droplet discharge heads that discharge active energy ray-curable ink to a recording medium, a carriage that mounts the recording head and moves in the main scanning direction, A plurality of irradiation units that are arranged on both sides of the recording head in the main scanning direction and irradiate the active energy ray-curable ink ejected to the recording medium with active energy rays, and input image data, A determination unit that determines two droplet discharge heads that discharge the active energy ray-curable ink, and arranges the two determined droplet discharge heads adjacent to each other in the main scanning direction, The distances between the intermediate points in the two droplet discharge heads and the plurality of irradiation units are equal to each other.
According to the present embodiment, it is possible to suppress bidirectional unevenness even for an image of a secondary color formed by two inks.

In the present embodiment, two droplet ejection heads that eject active energy ray-curable ink are determined based on the input image data. The distances between the determined midpoints of the two droplet discharge heads and the UV lamps 51 and 52 are equal.
For example, in the case of red of the secondary color, the distances between the UV lamps 51 and 52 are made equal at an intermediate point between the droplet discharge head 24y and the droplet discharge head 24m. Thereby, even if it is a secondary color, a bidirectional | two-way nonuniformity can be suppressed.

  Further, according to the aspect of the present embodiment, it is also effective when a droplet discharge head that discharges black ink and white ink is selected. As described above, black ink and white ink are often used in a single color. For this reason, by disposing black ink and white ink adjacent to each other, the distances between the droplet discharge heads 24k, 24w of both the black ink and the white ink and the UV lamps 51, 52 become substantially the same. Can be suppressed.

  On the other hand, in this embodiment, when black ink or white ink is used in a single color, bi-directional unevenness is likely to occur as compared to the first embodiment and the second embodiment. In the first and second embodiments, the distance between the droplet discharge head and the UV lamps 51 and 52 is the same. However, in this embodiment, the intermediate point between the two droplet discharge heads and the UV lamp 51 are used. , 52 are the same, and when attention is paid to one of the droplet discharge heads, the time until UV irradiation is slightly shifted in the forward path and the backward path. However, since the black ink and the white ink need only be arranged adjacent to each other, it is advantageous in that the configuration is easier than in the first and second embodiments. Therefore, it may be appropriately selected according to the image to be formed.

In addition, although description about the same point as the said embodiment is abbreviate | omitted, the structure in said embodiment is applicable in this embodiment.
For example, in an embodiment having a drive unit that relatively moves the recording head and the irradiation unit, and a control unit that controls the drive unit based on the determined droplet discharge head, It is preferable that the control unit controls the driving unit so that distances between the determined intermediate point in the two droplet discharge heads and the plurality of irradiation units are equal to each other.
In addition, the drive unit is configured so that the distance between the determined intermediate point between the two droplet discharge heads and the plurality of irradiation units is equal, and the distance can be arbitrarily changed. It is preferable to move the irradiating unit with respect to.

(Method for producing recorded matter)
As described above, according to the present invention, a method for producing a recorded matter is provided.
The method for producing a recorded matter of the present invention includes a step of discharging active energy ray-curable ink to a recording medium by a recording head comprising a plurality of droplet discharge heads, and a step of discharging the recording medium by a plurality of irradiation units. And a step of irradiating the active energy ray-curable ink with active energy rays, and a step of determining a droplet discharge head for discharging the active energy ray-curable ink based on input image data. A method is characterized in that the step is performed so that the distances between the determined droplet discharge head and the plurality of irradiation units are equal.

(Control program)
As described above, according to the present invention, a control program is provided.
The control program of the present invention includes a step of discharging active energy ray-curable ink to a recording medium by a recording head composed of a plurality of droplet discharge heads, and an active energy discharged to the recording medium by a plurality of irradiation units. A step of irradiating an active energy ray to the line curable ink, a step of moving the recording head and the irradiation unit relative to each other by a driving unit, and discharging the active energy ray curable ink based on the input image data. A step of determining a recording head to be executed by a computer, wherein the irradiation unit for irradiating the active energy rays is disposed on both sides of the recording head in a main scanning direction, and the determined droplet The distance between the ejection head and the plurality of irradiation units is equal.

  As described above, according to the present invention, it is possible to provide an image forming apparatus that can easily and inexpensively suppress image unevenness during bidirectional printing and improve print quality.

In the present invention, the “recording medium” is not limited to paper, but includes what is called a medium, a recording medium, a recording medium, a recording paper, a recording paper, and the like.
In addition, image formation, recording, printing, printing, and printing all have the same meaning, and “image forming apparatus” means an apparatus that forms an image by discharging liquid onto a medium.
“Image formation” not only applies an image having a meaning such as a character or a figure to a medium, but also applies an image having no meaning such as a pattern to the medium (simply landing a droplet on the medium). Meaning).

In addition, “ink” is used as a general term for all liquids that can perform image formation, and “image” is not limited to a planar one but is given to a three-dimensionally formed one. An image and an image formed by three-dimensionally modeling a solid itself are also included.
Further, the image forming apparatus includes both a serial type image forming apparatus and a line type image forming apparatus, unless otherwise limited.

DESCRIPTION OF SYMBOLS 2 Image formation part 3 Sub-scanning conveyance part 4 Paper feed part 5 Paper 8 Ink droplet 13 Conveyance belt 14 Recording medium 15 Tension roller 16 Paper discharge roller 17 Paper discharge roller 18 Charging roller 19 Carrying roller 21 Driven roller 22 Platen member 23 Head Carriage unit 24 Recording head 25 Sub tank 26 Ink cartridge 27 Main scanning motor 28B Driven pulley 29 Timing belt 37a Rotation center 37b Arm 38 Pressure roller 51, 52 UV lamp 53, 54 Ball screw rod 104 Paper discharge tray 121 Maintenance recovery device 122 For moisture retention Cap 124 Wiper member 126 Empty discharge receiving member 127 Opening 305, 306, 310 Conveyance path

JP 2005-342970 A

Claims (10)

A recording head comprising a plurality of droplet discharge heads for discharging active energy ray-curable ink to a recording medium;
A carriage mounted with the recording head and moving in the main scanning direction;
A plurality of irradiation units that are arranged on both sides of the recording head in the main scanning direction and irradiate the active energy ray-curable ink ejected to the recording medium with active energy rays;
A determination unit that determines a droplet discharge head for discharging the active energy ray-curable ink based on the input image data;
An image forming apparatus, wherein distances between the determined droplet discharge head and the plurality of irradiation units are equal.   2. The image forming apparatus according to claim 1, wherein a droplet discharge head that discharges black active energy ray-curable ink is arranged in the center of the main scanning direction in the recording head.   The image forming apparatus according to claim 1, wherein a droplet discharge head that discharges white active energy ray-curable ink is disposed in the center of the main scanning direction in the recording head. A recording head comprising a plurality of droplet discharge heads for discharging active energy ray-curable ink to a recording medium;
A carriage mounted with the recording head and moving in the main scanning direction;
A plurality of irradiation units that are arranged on both sides of the recording head in the main scanning direction and irradiate the active energy ray-curable ink ejected to the recording medium with active energy rays;
A determination unit that determines two droplet discharge heads that discharge the active energy ray-curable ink based on the input image data;
The two determined droplet discharge heads are arranged adjacent to each other in the main scanning direction, and the distances between the intermediate points of the determined two droplet discharge heads and the plurality of irradiation units are equal. An image forming apparatus. A drive unit that relatively moves the recording head and the irradiation unit;
A control unit that controls the drive unit based on the determined droplet discharge head,
The control unit controls the driving unit so that distances between the determined droplet discharge heads or intermediate points of the two determined droplet discharge heads and the plurality of irradiation units are equal to each other. The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus.   The distances between the determined droplet discharge heads or intermediate points between the determined two droplet discharge heads and the plurality of irradiation units are equal, and the distances can be arbitrarily changed. The image forming apparatus according to claim 5, wherein the driving unit moves the irradiation unit with respect to the recording head.   The image forming apparatus according to claim 1, wherein the active energy rays are ultraviolet rays.   The image forming apparatus according to claim 1, wherein the active energy ray curable ink is laminated on the recording medium. A step of discharging active energy ray-curable ink to a recording medium by a recording head composed of a plurality of droplet discharge heads;
Irradiating active energy ray curable ink discharged to the recording medium by a plurality of irradiation units with active energy rays;
A step of determining a droplet discharge head for discharging the active energy ray-curable ink based on input image data,
A method for producing a recorded matter, characterized in that distances between the determined droplet discharge head and the plurality of irradiation units are equal. A step of discharging active energy ray-curable ink to a recording medium by a recording head composed of a plurality of droplet discharge heads;
Irradiating active energy ray curable ink discharged to the recording medium by a plurality of irradiation units with active energy rays;
Relatively moving the recording head and the irradiation unit by a driving unit;
A step of determining a recording head for ejecting the active energy ray-curable ink based on input image data, and a control program for causing a computer to execute the process.
The irradiation unit for irradiating the active energy ray is disposed on both sides of the recording head in the main scanning direction,
A control program characterized in that distances between the determined droplet discharge head and the plurality of irradiation units are equal.