JP5096972B2 - Inkjet printer, printing unit and printing method therefor - Google Patents

Description

  The present invention relates to an inkjet printer that performs printing by ejecting ink onto a printing medium, a printing unit thereof, and a printing method thereof.

  2. Description of the Related Art Conventionally, an ink jet printer that prints on a print medium by ejecting ink from the print head while reciprocating a print head disposed opposite to the platen left and right with respect to the print medium placed on the platen It has been known. Among such ink jet printers, there is an ink jet printer that prints on a print medium by ejecting ultraviolet curable ink (hereinafter referred to as UV ink) having a property of being cured by being irradiated with ultraviolet rays from a print head. . Since this UV ink is excellent in weather resistance and water resistance, it becomes possible to use the printed material for, for example, outdoor advertising flyers and the like, and the usage of the printed material is greatly expanded as compared with the case of using the water-soluble ink. There is an advantage.

  By the way, an inkjet printer that performs printing by discharging UV ink is provided with an ultraviolet irradiation device for irradiating the UV ink attached to the printing medium with ultraviolet rays to cure the ink (for example, Patent Document 1 and Patent Document 1). 2). In recent years, an ink jet printer using an ultraviolet light emitting diode (hereinafter referred to as UVLED) has been developed as a light source for emitting ultraviolet light in the ultraviolet irradiation device. Here, the UVLED is an abbreviation for Ultra Bior Light Emitting Diode.

  As shown in FIG. 11A, the conventional printing unit 500 includes a right ultraviolet ray irradiation device 520R in which UVLEDs are arranged and configured to irradiate ultraviolet rays toward a print medium 501 located below. A pair of left ultraviolet irradiation devices 520L are fixedly disposed on the left and right sides of the print head 510. For convenience of explanation, the arrow directions shown in FIG. 11A are defined as front and rear and left and right. The print head 510 is, for example, a magenta print head 510M that discharges droplet-shaped magenta UV ink from a plurality of nozzles (not shown) provided on the lower surface toward the print medium 501, and similarly discharges yellow UV ink. The yellow print head 510Y, the cyan print head 510C that discharges cyan UV ink, and the black print head 510K that discharges black UV ink.

  When printing is performed on the print line 508 of the print medium 501, UV ink is ejected from each nozzle of the print head 510 while moving the print unit 500 back and forth by a predetermined number of passes above the print line 508, and desired. In this pattern, the print line 508 is attached in an overlapping manner. At this time, ultraviolet light having an irradiation intensity capable of completely curing the UV ink is emitted from the right ultraviolet irradiation device 520R and the left ultraviolet irradiation device 520L, and printing is performed by irradiating the printing line 508 with the ultraviolet light. The UV ink attached to the line 508 is cured and printed.

  11B and 11C are cross-sectional views of the state in which the UV ink ejected from the nozzles adheres to the print line 508 in the middle of printing on the print line 508 as described above. . In FIG. 11B, the uncured UV ink 512 is ejected on the fully cured UV ink 511 that has adhered to the print line 508 in the previous pass and is completely cured by being irradiated with ultraviolet rays. The attached state is shown. At this time, since the fully cured UV ink 511 is completely cured, the affinity between the fully cured UV ink 511 and the uncured UV ink 512 is poor, and the uncured UV ink 512 is raised in a granular shape due to surface tension. And become attached. In addition, after the uncured UV ink 512 is adhered in the form of particles, it has a poor affinity, and therefore, it is completely cured by being irradiated with ultraviolet rays in a state where it hardly spreads before being irradiated with ultraviolet rays.

On the other hand, the uncured UV ink 514 later in the current pass adheres to the print line 508 in the previous pass and is not cured (or hardly cured) on the previous uncured UV ink 513. FIG. 11 (c) shows the state of being discharged and attached. At this time, the affinity between the previous uncured UV ink 513 and the subsequent uncured UV ink 514 is good, and the subsequent uncured UV ink 514 mixes with the previous uncured UV ink 513 after adhering in a granular form. It bleeds together. The previous uncured UV ink 513 and the subsequent uncured UV ink 514 are mixed to form a mixed UV ink 515, which is irradiated with ultraviolet rays and completely cured.
JP 2004-1326 A JP 2004-188920 A

  By the way, when printing is performed on the printing medium 501 by the printing unit 500, the respective UV inks that overlap and adhere to the surface of the printing medium 501 are cured without being mixed and spread and spread and smoothed. Thus, it is possible to obtain a print medium 501 (desired print) on which desired printing has been performed. However, as shown in FIG. 11B, when the uncured uncured UV ink 512 overlaps and adheres to the completely cured fully cured UV ink 511, the fully cured UV ink 511 and the uncured UV ink are uncoated. While the ink 512 does not mix, the fully cured UV ink 511 repels the uncured UV ink 512, and the uncured UV ink 512 is irradiated with ultraviolet rays while being swelled in a granular shape on the surface of the fully cured UV ink 511. May be cured. As described above, when the printed matter printed with the UV ink cured in a granular form is compared with the desired printed matter, the appearance is different due to the reflection of light from the printed matter, and the print quality may be deteriorated.

  As shown in FIG. 11C, when the uncured uncured UV ink 514 overlaps and adheres to the uncured previous uncured UV ink 513, the subsequent uncured UV ink 514 was mixed with the previous uncured UV ink 513 and spread, and in this state, it was sometimes cured by being irradiated with ultraviolet rays. In this way, when the printed matter that is cured and printed in a state where the UV inks are mixed and blotted is compared with the desired printed matter, the color of the mixed and blotted portion looks different, which may reduce the print quality. was there.

  In view of the above-described problems, the present invention uses an ink jet printer in which the print quality is improved by stacking and adhering UV ink on the surface of a print medium in a smoothed state so as not to bleed, and the ink jet printer. It is an object to provide a printing unit and a printing method using the inkjet printer.

In order to solve the above problems, an ink jet printer according to the present invention is directed to a medium support member that supports a print medium (for example, the vacuum table 12a in the embodiment) and a surface of the print medium supported by the medium support member. A print head for ejecting and adhering ink; and an ultraviolet irradiation device for irradiating the surface of the print medium supported by the medium support member with ultraviolet light to cure the ink adhering to the surface of the print medium (for example, in the embodiment) Right UVLED unit 70R and left UVLED unit 70L), and the ultraviolet irradiation device is arranged on one side of the print head in a first direction which is a direction in which the print head reciprocates relative to the print medium. the first ultraviolet irradiation light source, a second ultraviolet irradiation light source on the other side, is orthogonal to the first direction The second direction with the first and second possible apparatus constituted moving means be positioned independently move the respective UV irradiation light source, each said first and second ultraviolet irradiation source control means for controlling the UV intensity morphism irradiation (e.g., the controller 23 in the embodiment) wherein the control means in the first and second ultraviolet irradiation light source, the gel it in ink adhered to the surface of the printing medium Control for irradiating the pre-cured ultraviolet light to be cured in a shape and control for irradiating the pre-cured ink with the main-curing ultraviolet light for main curing this , using the apparatus moving means By changing the positional relationship between the first and second ultraviolet irradiation light sources, the irradiation timing of the irradiation with the temporary curing ultraviolet light and the irradiation with the main curing ultraviolet light is controlled. Characterized in that it is configured to.

In the above-described inkjet printer according to the present invention, it is preferable that the print head and the ultraviolet irradiation device are mounted on a carriage that is moved relative to a print medium in a state of facing the medium support member. It is preferable that the means is configured to be able to move and position each of the first and second ultraviolet irradiation light sources independently in the second direction on the carriage.

Further, in the ink jet printer according to the present invention described above, before Symbol carriage is relatively moved in the second direction while being relatively reciprocated in the first direction relative to the print medium, the device moving means, Each of the first and second ultraviolet irradiation light sources can be positioned at either a position adjacent to the print head in the second direction or a position protruding away from the print head. It is preferable.

Further, the ultraviolet light source preferably has a configuration in which the irradiation intensity of ultraviolet rays can be set in at least two stages for the temporary curing and the main curing. Further, the ultraviolet light source preferably has a configuration using a light emitting diode. Further, the control unit may irradiate the first and second ultraviolet rays to the newly ejected ink so that the print head can eject the new ink so as to overlap the temporarily cured ink. It is preferable that the light source can be controlled to emit ultraviolet light for temporary curing.

The printing unit according to the present invention discharges and adheres ink to the surface of the print medium while moving relative to the surface of the print medium, and cures the attached ink by irradiating with ultraviolet rays. One of the print head used for applying and ejecting and adhering ink toward the surface of the print medium, and the print head in a first direction, which is a direction in which the print head reciprocates relative to the print medium A first ultraviolet irradiation light source on the side and a second ultraviolet irradiation light source on the other side, an ultraviolet irradiation device for irradiating the surface of the print medium with ultraviolet light and curing the ink adhering to the surface of the print medium; first and second of said first and second ultraviolet radiation independently by moving the light source is configured to be able to position the device moving means in a direction perpendicular to the direction And control means for controlling the irradiation morphism ultraviolet intensity of each of the first and second ultraviolet radiation source, the ink and the control means to the first and second ultraviolet irradiation light source, attached to the surface of the printing medium The apparatus moving means is configured to perform control for irradiating pre-curing ultraviolet light for curing the ink in a gel state and control for irradiating the pre-cured ink with ultraviolet light for main curing for main curing the ink. By changing the positional relationship between the first and second ultraviolet irradiation light sources using the above, the irradiation timing of the irradiation with the temporary curing ultraviolet light and the irradiation with the main curing ultraviolet light is controlled. and characterized in that it is.

A printing method according to the present invention includes a medium support member that supports a print medium, a print head that ejects ink onto the surface of the print medium supported by the medium support member, and the print medium. a first ultraviolet irradiation light source on one side of the print head in a first direction the print head is the direction of relative reciprocating movement comprising a second ultraviolet irradiation light source on the other side, before Symbol first direction An ink jet printer comprising an apparatus moving means configured to be able to independently move and position each of the first and second ultraviolet irradiation light sources in a second direction orthogonal to the first direction. A step of positioning the first and second ultraviolet irradiation light sources at predetermined positions by the apparatus moving means,
The print medium supported by the medium support member performs desired printing by ejecting ink from the print head onto the surface of the print medium and irradiating ultraviolet rays from the first and second ultraviolet irradiation light sources. Curing the ink adhering to the surface of the print medium, and in the step, the ink is moved from the print head to the surface of the print medium while the print head is relatively reciprocated in the first direction. When performing desired printing by discharging, the step of irradiating the ink adhering to the surface of the print medium with ultraviolet rays for pre-curing that hardens the ink in a gel state, and the ultraviolet rays for main-curing the pre-cured ink It possesses a step of irradiating, by changing the positional relationship of the first and second ultraviolet irradiation light source using the device moving means, for the pre-curing And irradiation of the external line, wherein the printing irradiation timing control to the irradiation of ultraviolet light for final curing takes place.

According to the ink jet printer according to the present invention, the first ultraviolet irradiation light source on one side of the print head those of the first direction the print head is a direction relative reciprocating relative to the print medium, the other side Two ultraviolet irradiation light sources, and each of the first and second ultraviolet irradiation light sources can be independently moved and positioned in a second direction orthogonal to the first direction. comprising a device moving means comprises a control means for controlling the irradiation morphism ultraviolet intensity of the first and second ultraviolet irradiation source, the control means to the ultraviolet radiation source, the ink adhered to the surface of the printing medium a control for irradiating ultraviolet rays for temporary curing to cure it into a gel, and controlled to irradiate the ultraviolet light for final curing to the cure this ink is temporarily cured, is possible to configure the device By changing the positional relationship of the first and second ultraviolet irradiation light sources using a moving means, the irradiation timing between the irradiation with the temporary curing ultraviolet light and the irradiation with the main curing ultraviolet light is controlled. Ru is configured. With this configuration, the positional relationship (distance) between the print head and the ultraviolet irradiation device can be changed. For this reason, when ink is ejected from the print head and adhered to the print medium and printing is performed by irradiating the ultraviolet light from the ultraviolet irradiation device to cure the ink adhered to the print medium, the ink adheres to the print medium. It is possible to control the time interval from irradiation to irradiation with ultraviolet rays. Therefore, for example, the irradiation timing of ultraviolet rays can be controlled by changing the positional relationship between the print head and the ultraviolet irradiation device according to the type of ink and printing medium used for printing. In addition, since the ink attached to the surface of the print medium is configured to be capable of irradiating with ultraviolet light for temporary curing that cures the ink in a gel state and control to irradiate ultraviolet light for main curing, for example, the ink Even when the viscosity of the ink is low, the ink can be fixed on the surface of the printing medium in a smoothed state so that it does not bleed, and the quality is almost the same as the desired printed matter. Printing is possible.

  Further, it is preferable that the print head and the ultraviolet irradiation device are mounted on a carriage that is relatively moved with respect to the print medium, and the apparatus moving means relatively moves the ultraviolet irradiation device on the carriage. When configured in this way, the apparatus moving means can control the irradiation timing of the ultraviolet rays by moving the movable ultraviolet irradiation device with respect to, for example, a fixed print head on the carriage. Therefore, the irradiation timing of ultraviolet rays can be controlled with a simple apparatus configuration.

The ultraviolet irradiation light source preferably has a configuration in which the irradiation intensity of ultraviolet rays can be set in at least two stages for the temporary curing and the main curing . When configured in this way, the intensity of the ultraviolet rays emitted from the ultraviolet irradiation light source can be controlled by selecting a desired intensity from at least two set intensity levels. Therefore, it becomes easy to control the irradiation intensity of ultraviolet rays, and the control system of the ink jet printer can be simply configured.

Further, the ultraviolet irradiation light source preferably has a configuration using a light emitting diode. When the light emitting diode is used as described above, for example, the current value of the supply current to the light emitting diode is changed, and at the same time, the intensity of the ultraviolet ray changes. Therefore, it is possible to irradiate ultraviolet rays having a desired intensity with almost no time lag with respect to ultraviolet intensity control. Therefore, the ink adhering to the print medium can be cured without unevenness.

According to the printing unit of the present invention, the first ultraviolet irradiation light source is provided on one side of the print head in the first direction, which is the direction in which the print head reciprocates relative to the print medium, and the second light source is provided on the other side. comprising a UV radiation source, which is configured to be able to position it independently move each of the first second of the first and second ultraviolet irradiation light source in a direction perpendicular to the direction a device moving means, and control means for controlling the irradiation morphism ultraviolet intensity of each of the first and second ultraviolet irradiation source, the control means to the ultraviolet radiation source, the ink adhered to the surface of the printing medium a control for irradiating ultraviolet rays for temporary curing to cure it into a gel, and controlled to irradiate the ultraviolet light for final curing to the cure this ink is temporarily cured, is possible to configure the device moves By changing the positional relationship between the first and second ultraviolet irradiation light sources using a stage, the irradiation timing of the irradiation with the temporary curing ultraviolet light and the irradiation with the main curing ultraviolet light is controlled. Ru is configured. Thus, for example, even when the optimal ultraviolet irradiation timing differs depending on, for example, the type of ink used for printing and the print medium, the ultraviolet irradiation device is moved relative to the print head so that the print head and the ultraviolet irradiation By changing the positional relationship with the apparatus, it is possible to irradiate ultraviolet rays at an optimal timing. In addition, since the ink attached to the surface of the print medium is configured to be capable of irradiating with ultraviolet light for temporary curing that cures the ink in a gel state and control to irradiate ultraviolet light for main curing, for example, the ink Even when the viscosity of the ink is low, the ink can be fixed on the surface of the printing medium in a smoothed state so that it does not bleed, and the quality is almost the same as the desired printed matter. Printing is possible.

In the printing method according to the present invention, a first ultraviolet irradiation light source is provided on one side of the print head and a second light source is provided on the other side in a first direction, which is a direction in which the print head relatively reciprocates with respect to the print medium. comprising a UV radiation source, before SL to a second direction perpendicular to the first direction, configured to be capable of be positioned independently by moving each of the first and second ultraviolet irradiation source A printing method performed using an ink jet printer configured with the apparatus moving means , wherein the apparatus moving means positions the first and second ultraviolet irradiation light sources at predetermined positions, respectively. Yes a step of irradiating ultraviolet rays for temporary curing to cure it to gel the ink adhered to the surface of the print medium, and a step of irradiating ultraviolet light for final curing ink is temporarily cured By changing the positional relationship between the first and second ultraviolet irradiation light sources using the apparatus moving means, the irradiation timing of the irradiation with the temporary curing ultraviolet light and the irradiation with the main curing ultraviolet light is changed. The printing is performed under control . For example, the ink adheres to the print medium by performing control to move and position each of the first and second ultraviolet irradiation light sources independently according to the type of ink used for printing and the print medium. Then, the time interval from when it is irradiated with ultraviolet rays can be controlled. And a step of irradiating the ink adhering to the surface of the print medium with a pre-curing ultraviolet ray for curing the ink in a gel state and a step of irradiating the ultraviolet ray for main curing with the apparatus moving means. By changing the positional relationship between the first and second ultraviolet irradiation light sources, printing is performed by controlling the irradiation timing of the temporary curing ultraviolet irradiation and the main curing ultraviolet irradiation. Because it is configured, for example, even when the viscosity of the ink is low, the ink can be fixed on the surface of the print medium in a smoothed state so as not to bleed, and is visible even when compared with the desired printed matter. High-quality printing with almost no difference is possible.

  Hereinafter, a preferred embodiment of the present invention will be described with reference to Examples 1 and 2 with reference to FIGS. For convenience of explanation, the directions of arrows shown in the drawings will be referred to as front and rear, left and right, and top and bottom, respectively.

  In FIG. 1, as an example of an inkjet printer to which the present invention is applied, printing is performed by moving a print head in two orthogonal axes (X axis-Y axis) in a horizontal plane with respect to a print medium fixedly held on a table. The perspective view which looked at the inkjet printer 1 which performs desired printing with respect to a medium from diagonally forward is shown. The ink jet printer 1 includes a support portion 10 that forms a base portion in a lower portion, and a printing portion 50 that is disposed above the support portion 10 so as to be movable. The support unit 10 is mainly composed of a main body frame 11, a support table 12, a vacuum blower 13, and a control unit 20. The main body frame 11 horizontally supports a support table 12 mounted and fixed thereon, and serves as a mounting base for each mechanism.

  The support table 12 is formed in a rectangular shape in plan view, and a vacuum table 12a for mounting and holding the flat print medium 2 thereon is formed at the center. The surface of the vacuum table 12a is formed with a number of fine air holes penetrating vertically, and these air holes communicate with a decompression chamber (not shown) provided on the lower surface side of the vacuum table 12a. . Further, guide grooves 12b and 12b extending in the front-rear direction are formed on the left and right end surfaces of the support table 12, and are fitted to front and rear guides 51a and 51a formed on the left and right sides of the printing unit 50 described later.

  The vacuum blower 13 communicates with the decompression chamber and exhausts the air in the decompression chamber to set a negative pressure, or feeds air into the decompression chamber and discharges it from the air hole. The print medium 2 is placed at the origin position on the vacuum table 12a, the vacuum chamber 13 is set to a negative pressure by the vacuum blower 13, and the print medium 2 is vacuum-adsorbed on the surface of the vacuum table 12a and fixedly held. When the desired printing on the printing medium 2 is completed and the printing medium 2 is removed from the vacuum table 12a, the printing medium 2 is floated and removed easily by sending air into the decompression chamber and discharging it from the air holes. be able to.

  The control unit 20 is installed at the front end portion of the support table 12 and mainly includes an operation panel 21, a stop button 22, and a controller 23. The operation panel 21 is provided with operation buttons (not shown) for operating the ink jet printer 1 and a display panel (not shown) for displaying the operation status. The stop button 22 is a button for stopping the operation of the inkjet printer 1.

  The controller 23 is configured inside the control unit 20, and for example, the room temperature of the work room where the inkjet printer 1 is installed, the print medium 2 used for printing, the type of UV ink, and the like are input. In addition, the controller 23 provides operation signals to the front / rear drive mechanism 59, the left / right drive mechanism 69, the right UVLED unit 70R, the left UVLED unit 70L, the color-specific print heads 62M, 62Y, 62C, and 62K, the servo motor 81, and the like. Output is enabled and connected. Then, an operation signal is output to these components so that the ink jet printer 1 is in a desired operation state.

  The controller 23 includes a memory (not shown). In this memory, the relationship between the room temperature and the viscosity of the UV ink determined by experiment or simulation, and the relationship between the viscosity of the UV ink and the time required for smoothing are stored as a database. Therefore, when the room temperature of the working chamber, the print medium 2 used for printing, and the type of UV ink are input to the controller 23, the viscosity of the UV ink is obtained by referring to the database. Further, the time required for smoothing is obtained by referring to the database based on the obtained viscosity of the UV ink.

  The room temperature of the work chamber is input to the controller 23 because the room temperature is related to the smoothing of the UV ink, the speed of the bleeding between the UV inks, and the like. In general, the viscosity of a liquid such as UV ink changes with a change in the room temperature. For example, when the room temperature rises, the viscosity of the UV ink decreases. When the viscosity of the UV ink is low, the UV ink ejected from the nozzle adheres to the print medium 2 and then spreads and smoothes in a short time. At this time, the UV inks in contact with each other are mixed and spread in a short time. As described above, the room temperature of the working chamber affects the viscosity of the UV ink, and as a result, affects the smoothing and bleeding of the UV ink attached to the printing medium 2. Further, for example, a temperature in the vicinity of the print head 62 in the print unit 60 described later can be detected. By doing so, it becomes possible to detect the viscosity of the UV ink more accurately.

  The printing unit 50 is mainly composed of a base 51, a guide rail 52, and a printing unit 60. The base 51 is a substantially rectangular parallelepiped extending left and right, and front and rear guides 51a and 51a formed in the vicinity of the left and right ends are fitted with the guide grooves 12b and 12b, and slide back and forth across the upper side of the support table 12. It is supported movably. The guide rail 52 extends to the left and right and is formed on the front surface of the base 51. Further, left and right guides 65 formed on the rear surface of a carriage 63, which will be described later, are fitted to the guide rails 52, and the printing unit 60 is supported so as to be slidable in the left and right directions. Various well-known techniques can be used for the front / rear drive mechanism 59 that slides the base 51 back and forth, and the left / right drive mechanism 69 that slides the print unit 60 left and right. Is omitted.

  As shown in FIGS. 1 and 2, the printing unit 60 is mainly composed of a print head 62, a carriage 63, a right UVLED unit 70 </ b> R, a left UVLED unit 70 </ b> L, and a front / rear drive device 80, and an outer peripheral portion is covered with a cover 61. ing. The print head 62 includes, for example, color-specific print heads 62M, 62Y, 62C, and 62K corresponding to the respective colors of magenta (M), yellow (Y), cyan (C), and black (K). A plurality of nozzles (not shown) capable of ejecting the UV ink of each color downward are arranged on a plane extending in the front-rear and left-right directions on the lower surfaces of the color-specific print heads 62M, 62Y, 62C, 62K. Has been. A storage tank 53 that stores UV ink of each color is disposed on the upper surface of the left end of the base 51. The storage tank 53 includes, for example, storage tanks 53M, 53Y, 53C, and 53K corresponding to colors of magenta (M), yellow (Y), cyan (C), and black (K). A storage tank and a print head communicate with each other via a pipe line (not shown) for each color, and UV ink is appropriately sent from the storage tank to the print head.

  The carriage 63 serves as a mounting base for the print head 62, the right UVLED unit 70R, the left UVLED unit 70L, and the front / rear drive device 80. A print head 62 is mounted and fixed near the front end of the carriage 63. The carriage 63 is formed with guide grooves 64 and 64 extending forward and backward on the left and right sides of the print head 62. The right UVLED unit 70R and the left UVLED unit 70L are guided by the guide grooves 64 and 64. Can be slid back and forth. A front-rear drive device 80 whose outer peripheral portion is covered by a drive device box 66 is installed behind the print head 62. A servo motor 81, a drive shaft 82, a drive gear 83, a driven gear 84, and an output shaft 85, which will be described later. Is rotatably supported in the drive device box 66. A left and right guide 65 that can be fitted to the guide rail 52 is formed on the rear end surface of the carriage 63 so as to extend left and right.

The right UVLED unit 70R is arranged on the right side of the print head 62, the left UVLED unit 70 L is disposed to the left. Here, the right UVLED unit 70R and the left UVLED unit 70L have the same configuration, and the right UVLED unit 70R will be described below. The right UVLED unit 70R is provided with a rack 71 that is erected upward on the upper surface portion and that extends to the left and right. Further, the front and rear side surfaces and the left and right side surfaces of the right UVLED unit 70R are covered by a flat cover 72 and open downward. In addition, inside the space surrounded by the rack 71 and the cover 72, UVLEDs (not shown) capable of emitting ultraviolet rays are disposed. Therefore, by operating the UVLED, ultraviolet rays are irradiated downward from the lower surface of the right UVLED unit 70R. The ultraviolet rays irradiated from the lower surface of the right UV LED unit 70R have, for example, substantially the same front-rear width as the nozzles formed on the lower surface of each color print head.

  For example, the current value of the supply current is controlled by the controller 23, and the UVLED can irradiate ultraviolet rays having an irradiation intensity corresponding to the current value. For example, the irradiation intensity when the current of the current value A1 is supplied is an intensity for pre-curing uncured UV ink into a gel-like semi-cured state (hereinafter referred to as pre-curing ultraviolet light). . In addition, for example, the irradiation intensity when the current of the current value A2 is supplied is the intensity at which the UV ink in the semi-cured state that has been preliminarily cured and gel-cured is fully cured (hereinafter referred to as UV for main curing). Called). Further, the UV ink is actually cured by receiving, for example, ultraviolet rays having an irradiation intensity for temporary curing a plurality of times, and receiving an integrated amount of ultraviolet rays necessary for the main curing. The controller 23 can also control the irradiation intensity of the ultraviolet rays from the UVLEDs to be zero, that is, prevent the ultraviolet rays from being emitted by changing the current value.

  The front-rear drive device 80 is mainly composed of a servo motor 81, a drive shaft 82, a drive gear 83, a driven gear 84, an output shaft 85, and pinions 86R and 86L. The servo motor 81 can receive an operation signal output from the controller 23 and can be rotationally driven by numerical control. The drive shaft 82 is an axis to which the rotational driving force of the servo motor 81 is output. A drive gear 83 is attached to the left end portion of the drive shaft 82, and the drive gear 83 and the driven gear 84 attached to the output shaft 85 are engaged with each other. Pinions 86R and 86L are respectively attached to the ends of the output shaft 85, and these mesh with the rack 71 of the right UVLED unit 70R and the rack 71 of the left UVLED unit 70L. When the inkjet printer 1 is not printing, the right UVLED unit 70R and the left UVLED unit 70L are positioned on the front side of the guide grooves 64, 64 as shown in FIG.

  The print unit 60 is reciprocally moved left and right above the print medium 2 by the left and right drive mechanism 69 with the print head 62, the right UVLED unit 70R, the left UVLED unit 70L, and the front and rear drive device 80 mounted on the carriage 63. Then, it is slid back and forth by the front and rear drive mechanism 59. When the servo motor 81 is driven to rotate, the right UVLED unit 70R and the left UVLED unit 70L are slid back and forth integrally with the print head 62.

  Up to this point, the respective constituent members of the ink jet printer 1 have been described. Hereinafter, the operation of each constituent member when performing printing using the ink jet printer 1 is described in two cases with reference to the flowchart shown in FIG. An example will be described. Before starting printing, the printing unit 50 is located at the rear end of the support table 12, and the printing unit 60 is located at a position to the left of the left end of the printing medium 2 (hereinafter referred to as a home position). Suppose you are.

  First, a case where printing is performed using the ink jet printer 1 in a working room having a low indoor temperature will be described below as an example (hereinafter referred to as a low temperature case). In this case, the viscosity of the UV ink is high, and even if UV inks contact each other in an uncured state, they do not ooze or mix immediately. Assume that it takes time.

  In step 1, the operator inputs the type of the print medium 2 on which printing is performed and the type of UV ink used for printing to the controller 23 via the operation panel 21. At this time, the room temperature of the working room in which the inkjet printer 1 is installed is also detected and input to the controller 23.

  Proceeding to step 2, the controller 23 calculates the time required for smoothing the UV ink used for printing at the detected room temperature. In this calculation method, as described above, the controller 23 first obtains the viscosity of the UV ink by referring to the database stored in the memory, and then obtains the time required for smoothing from the viscosity of the UV ink.

Proceeding to step 3, based on the time required for smoothing obtained in step 2, immediately after adhering to the printing medium 2, the ultraviolet rays from the right UVLED unit 70R and the left UVLED unit 70L are irradiated to the printing medium 2 It is determined whether the attached UV ink is cured. If the viscosity of the UV ink is low and the time required for smoothing is short, it is preferable to irradiate ultraviolet rays as soon as possible as soon as possible in order to suppress the occurrence of bleeding and the like. It is determined that the ultraviolet rays are to be irradiated, and the process proceeds to Step 5. On the other hand, if the viscosity of the UV ink is high and the time required for smoothing is long, it is preferable to irradiate with ultraviolet rays after waiting for smoothing as much as possible after adhesion. Is determined not to be irradiated with ultraviolet light, and the process proceeds to step 4. As described above, since it is assumed here that it takes time until smoothing, it is determined in step 3 that ultraviolet rays are not irradiated immediately after adhesion to the UV ink, and the process proceeds to step 4.

  When the process proceeds from step 3 to step 4, an operation signal is output from the controller 23 to the servo motor 81, and the servo motor 81 is driven to rotate based on the operation signal. At this time, the rotational driving force generated in the servo motor 81 is transmitted to the driven gear 84 via the driving gear 83 attached to the driving shaft 82. Then, the pinions 86R and 86L attached to the output shaft 85 are rotationally driven, and the right UVLED unit 70R and the left UVLED unit 70L are slid rearward along the guide grooves 64 and 64 (FIG. 3A). See).

  Proceeding from step 4 to step 5, an example of the printing procedure in step 5 will be described with reference to FIGS. 4A and 4B, which are plan views of the printing unit 60 in which the description of the front-rear drive device 80 is omitted. To do. An outline of the printing procedure will be described. The printing unit 60 is moved by the left / right drive mechanism 69 from the home position shown in FIG. 4A to the right side of the right end portion of the printing medium 2 shown in FIG. (Referred to as a position) and reciprocally moved back to the home position. At this time, UV ink whose ejection is controlled is ejected from the nozzles of the color-specific print heads while reciprocating left and right by a predetermined number of passes above the print medium 2 and attached to the print medium 2 in a desired pattern. Here, the number of passes is the number of passes through the same area of the print medium 2 while ejecting UV ink from the nozzles. Further, at this time, ultraviolet rays are irradiated toward the print medium 2 from the right UVLED unit 70R and the left UVLED unit 70L.

  Here, a case will be described in which UV ink is attached in a desired pattern by four passes to the print line 2a extending left and right on the surface of the print medium 2. Behind this print line 2a is a printed line 2b which is the same front and rear width as the print line 2a and has an uncured state in which UV ink is attached in a desired pattern, as will be described later. Yes.

  In the first pass, the printing unit 60 is moved from the home position to the reverse position. At this time, UV ink is ejected and adhered from the nozzle toward the printing line 2a, and is in an uncured state. Furthermore, at this time, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as to emit ultraviolet rays for temporary curing. Therefore, the UV ink that has been attached to the printed line 2b and is in an uncured state is preliminarily cured into a gel-like semi-cured state by being irradiated with the ultraviolet light for temporary curing.

  In the second pass, the printing unit 60 is moved from the reverse position to the home position. At this time, UV ink is ejected from the nozzles toward the printing line 2a and adheres so as to overlap the UV ink that has adhered in the first pass. However, as described above, since the viscosity of the UV ink is high, even if the UV ink contacts in an uncured state, it hardly bleeds or mixes. Further, at this time, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as not to emit ultraviolet rays. While the second pass is being performed, the UV ink that has been temporarily cured in the printed line 2b gradually spreads flatly.

  In the third pass, the printing unit 60 is moved in the same manner as in the first pass. At this time, UV ink is ejected from the nozzles toward the printing line 2a and adheres so as to overlap with the UV ink adhered in the first pass and the second pass. However, as described in the second pass, the ink is almost blurred or mixed. It does n’t fit. Further, at this time, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as not to emit ultraviolet rays. It is assumed that the UV ink that has been pre-cured in the printed line 2b spreads flatly while the third pass is being executed, and is smoothed when the third pass is completed.

  In the fourth pass, the printing unit 60 is moved in the same manner as in the second pass. At this time, UV ink is ejected toward the printing line 2a and adheres so as to overlap the UV ink deposited in the first to third passes. However, as described in the second pass, the ink is hardly blotted or mixed. Further, at this time, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as to emit ultraviolet rays for main curing. Therefore, when the fourth pass is executed, uncured UV ink is adhered to the print line 2a in a desired pattern. Further, the UV ink that has been pre-cured in the printed line 2b is irradiated with ultraviolet light for main curing in a smoothed state and is finally cured, and is fixed to the print medium 2 to be subjected to desired printing.

  When the fourth pass is completed, the printing unit 60 is slid forward by the printing line 2a by the front / rear drive mechanism 59 while being stationary at the home position. Thereafter, in the same manner as in the first to fourth passes described above, the UV ink is applied to the print line adjacent to the front of the print line 2a. Further, at this time, the UV ink which is attached to the printing line 2a and is uncured is preliminarily cured by being irradiated with the ultraviolet light for temporary curing in the first pass, as in the above-described printed line 2b. The film is finally cured in a smoothed state and fixed to the print medium 2. By repeatedly performing UV ink adhesion, temporary curing, and main curing until the front end of the printing medium 2 is reached, printing on the printing medium 2 is completed and this flow ends.

  Next, a case where printing is performed using the inkjet printer 1 in a working room having a high room temperature will be described as an example below (hereinafter referred to as a high temperature case). In this case, the viscosity of the UV ink is low, and the UV inks tend to bleed or mix when in contact with each other in an uncured state, and after being attached to the print medium 2, they are smoothed in a short time. Assume.

  As in the case of the low temperature described above, the time required for smoothing is obtained in step 2 based on each data input in step 1. As described above, since it is assumed here that smoothing is performed in a short time, in step 3, it is determined that the UV ink is irradiated immediately after adhering to the UV ink, and the process proceeds to step 5. At this time, the right UVLED unit 70R and the left UVLED unit 70L remain in the front side of the guide grooves 64, 64 as shown in FIG.

  An example of the printing procedure in Step 5 will be described with reference to FIGS. 5A and 5B which are plan views of the printing unit 60 in which the description of the front and rear drive device 80 is omitted. Here, the operation of the printing unit 60 and the UV ink ejection control for each pass are the same as in the case of the low temperature described above.

  In the first pass, UV ink is ejected toward the printing line 2a. At this time, the left UVLED unit 70L is controlled by the controller 23 to emit ultraviolet rays for temporary curing, while the right UVLED unit 70R is controlled not to emit ultraviolet rays. Therefore, the UV ink adhering to the printing line 2a is temporarily cured by being irradiated with ultraviolet rays for temporary curing.

  In the second pass, the UV ink is ejected and adhered so as to overlap the UV ink temporarily cured in the first pass. Here, since the UV ink adhering in the first pass is temporarily cured, the UV ink adhering in an overlapping manner does not mix with the UV ink adhering in the first pass and bleed by the surface tension. There is nothing. At this time, the right UVLED unit 70R is controlled by the controller 23 to emit ultraviolet rays for temporary curing, while the left UVLED unit 70L is controlled not to emit ultraviolet rays. Therefore, the UV ink adhering to the printing line 2a in the second pass is in a state of being temporarily cured by being irradiated with ultraviolet rays for temporary curing.

  In the third pass, the UV ink is ejected and adhered so as to overlap the UV ink temporarily cured in the first pass and the second pass. Here, since the UV ink adhered in the first pass and the second pass is temporarily cured, the UV ink adhering in an overlapping manner may be mixed with the UV ink adhered in the first pass and the second pass and spread. And is not repelled by surface tension. At this time, the left UVLED unit 70L is controlled by the controller 23 to emit ultraviolet rays for temporary curing, while the right UVLED unit 70R is controlled not to emit ultraviolet rays. Therefore, the UV ink attached to the printing line 2a in the third pass is in a state of being temporarily cured by being irradiated with ultraviolet rays for temporary curing.

  In the fourth pass, the UV ink is ejected and adhered so as to overlap the UV ink temporarily cured in the first pass to the third pass. Here, since the UV ink adhered in the first pass to the third pass is temporarily cured, the UV ink adhering to overlap may be mixed with the UV ink adhered in the first pass to the third pass and spread. And is not repelled by surface tension. At this time, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as to emit ultraviolet rays for main curing. Therefore, the UV ink attached to the printing line 2a in the first pass to the fourth pass is in a state of being fully cured by being irradiated with ultraviolet rays for main curing. Since the UV ink used here is smoothed in a short time after adhering to the printing medium 2 as described above, the UV ink is sufficiently smoothed when irradiated with ultraviolet rays for main curing, and thus smoothed. It is fixed to the print medium 2 in a state. When the operations from the first pass to the fourth pass are performed over the entire print area of the print medium 2, printing on the print medium 2 is completed, and this flow ends.

  Here, the effects of the inkjet printer 1 according to the first embodiment are summarized as follows. First, the front and rear drive device 80 is configured such that the right UVLED unit 70R and the left UVLED unit 70L are slidable rearward from the left and right sides of the print head 62. For example, when it takes a long time for the UV ink to adhere to the printing medium 2 and smooth, as in the case of the low temperature described above, the right and left UVLED units 70R and 70L are moved backward by the front-rear drive device 80. Move the slide. By moving in this way, it becomes possible to irradiate the UV ink attached in the left-right reciprocation before the printing unit 60 is moved forward by the front-rear drive mechanism 59 with ultraviolet rays. That is, it is possible to leave a time from when the UV ink is adhered to when the UV light is irradiated. Therefore, during this time, the UV ink adhering to the printing medium 2 can be spread and smoothed, so that the UV ink can be fixed to the printing medium 2 by irradiating ultraviolet rays in a smoothed state, and the printing quality can be improved. .

  Second, the right UVLED unit 70 </ b> R and the left UVLED unit 70 </ b> L can be in a state of being positioned on the left and right sides of the print head 62 by the front / rear drive device 80 or in a state of being slid rearward. Therefore, for example, when smoothing is performed in a short time (for example, in the case of the above-described high temperature) based on the time required for smoothing after UV ink adheres to the print medium 2, each UVLED unit is connected to the print head 62. On the other hand, when it takes time for smoothing (for example, in the case of the above-mentioned low temperature), it can be controlled to slide backward. In this way, the front and rear positions of each UVLED unit are controlled according to the time required for smoothing to control the irradiation timing of ultraviolet rays, and the intensity of ultraviolet rays (for temporary curing or main curing) irradiated at this time is controlled. By controlling, it is possible to fix the UV ink on the surface of the print medium 2 in a smoothed state so as not to bleed and improve the print quality.

  Hereinafter, the ink jet printer 5 according to the second embodiment in which the printing unit 90 is mounted will be described. As shown in FIGS. 6A and 6B, the front / rear drive device 80 ′ of the printing unit 90 has a configuration obtained by modifying the front / rear drive device 80 described in the first embodiment. Therefore, the same members as those in the above-described first embodiment are denoted by the same reference numerals and description thereof will be omitted, and the following description will focus on portions different from those in the above-described first embodiment.

  The front / rear drive device 80 'of the printing unit 90 includes a servo motor 81R, a drive shaft 82R, a drive gear 83R, a driven gear 84R, an output shaft 85R, a pinion 86R, a servo motor 81L, a drive shaft 82L, a drive gear 83L, a driven gear 84L, The output shaft 85L and the pinion 86L are mainly configured. When the servo motor 81R is driven, the right UVLED unit 70R slides back and forth through the drive shaft 82R, the drive gear 83R, the driven gear 84R, the output shaft 85R, and the pinion 86R. Similarly, when the servo motor 81L is driven, the left UVLED unit 70L slides back and forth through the drive shaft 82L, the drive gear 83L, the driven gear 84L, the output shaft 85L, and the pinion 86L. Therefore, when the controller 23 independently controls the servo motor 81R and the servo motor 81L, the right UVLED unit 70R and the left UVLED unit 70L can be slid back and forth independently. When the inkjet printer 5 is not printing, the right UVLED unit 70R and the left UVLED unit 70L are positioned in front of the guide grooves 64 and 64 as shown in FIG.

  The constituent members of the ink jet printer 5 according to the second embodiment have been described above. Hereinafter, the operation of each constituent member when performing printing using the ink jet printer 5 will be described with reference to the flowchart shown in FIG. explain. Hereinafter, a case where printing is performed using the inkjet printer 5 in a working room having a high indoor temperature will be described as an example. In this case, the viscosity of the UV ink is low, and if the UV inks come into contact with each other in an uncured state, they tend to bleed or mix, but it takes some time to smooth after adhering to the printing medium 2. Assume.

  As in the case of the first embodiment, the time required for smoothing is obtained in step 2 based on the data input in step 1, and the process proceeds to step 3. As described above, the UV ink in this case tends to bleed, but it takes some time for smoothing. Therefore, after temporarily curing immediately after adhering to the printing medium 2, it waits for smoothing instead of immediately after adhering, and then main curing. It is preferable to irradiate with ultraviolet rays so that Accordingly, the process proceeds from step 3 to step 4, and an operation signal is output from the controller 23 to, for example, the servo motor 81L, and the servo motor 81 is driven to rotate based on the operation signal. By doing so, the left UVLED unit 70L is slid rearward along the guide groove 64 (see FIG. 6A).

  FIG. 7A shows a plan view of the printing unit 90 from which the description of the front / rear drive device 80 ′ is omitted as an example of the procedure when printing is performed on the print medium 2 from Step 4 to Step 5. This will be described with reference to FIG. FIG. 8 shows a cross-sectional view when the UV ink is stacked for each pass, and will be described with reference to FIG. Below, the case where UV ink is made to adhere with the desired pattern with respect to the printing line 2a of the surface of the printing medium 2 is demonstrated. Further, it is assumed that a printed line 2b in which the UV ink attached in a desired pattern is temporarily cured is adjacent to the rear of the printing line 2a. The reciprocating movement of the printing unit 90 to the left and right (number of passes) and the discharge control of UV ink from the nozzles in each pass are the same as in the first embodiment.

  In the first pass, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as not to emit ultraviolet rays. When the first pass is executed, the UV ink 62a is ejected toward the printing line 2a and adheres in an uncured state (see FIG. 8A). Further, while the first pass is being executed, the UV ink adhered to the printed line 2b and temporarily cured gradually spreads on the surface of the print medium 2.

  In the second pass, the right UVLED unit 70 </ b> R is controlled by the controller 23 to emit ultraviolet rays for temporary curing, and the left UVLED unit 70 </ b> L is controlled not to emit ultraviolet rays. When the second pass is executed, the UV ink 62b is ejected and adhered toward the printing line 2a, and the UV ink 62a and the UV ink 62b are temporarily cured by being irradiated with ultraviolet rays for temporary curing (FIG. 8). (See (b)). At this time, when the UV ink 62b adheres to the printing line 2a, the UV ink 62b comes into contact with the uncured UV ink 62a. There is almost nothing. Further, while the second pass is being executed, the UV ink that has been attached to the printed line 2 b and temporarily cured is gradually spread on the surface of the printing medium 2.

  In the third pass, the right UVLED unit 70R and the left UVLED unit 70L are controlled by the controller 23 so as not to emit ultraviolet rays. When the third pass is executed, the UV ink 62c is ejected toward the printing line 2a, adheres so as to overlap the UV ink 62a and the UV ink 62b that are temporarily cured, and is in an uncured state ( (See FIG. 8 (c)). Since the UV ink 62c has good affinity with the UV ink 62a and the UV ink 62b, the UV ink 62c does not repel each other and gradually spreads, and does not mix and bleed. Further, when the third pass is completed, the UV ink attached to the printed line 2b and temporarily cured is spread and smoothed on the surface of the print medium 2.

  In the fourth pass, the right UVLED unit 70R is controlled by the controller 23 so as to emit ultraviolet light for temporary curing, and the left UVLED unit 70L is controlled so as to emit ultraviolet light for main curing. When the fourth pass is executed, the UV ink 62d is ejected toward the printing line 2a, and adheres to the temporarily cured UV ink 62a, UV ink 62b, and UV ink 62c. At this time, when the UV ink 62d adheres to the printing line 2a, the UV ink 62d comes into contact with the uncured UV ink 62c. Immediately after the attachment, the UV ink 62c and the UV ink 62d are temporarily cured. Therefore, they hardly bleed or mix (see FIG. 8D). Further, the UV ink that has been temporarily cured by adhering to the printed line 2 b is irradiated with ultraviolet rays for main curing, and is finally cured in a smoothed state and fixed to the printing medium 2. In this way, printing for the printed line 2b is completed. By repeatedly performing UV ink adhesion, temporary curing, and main curing until the front end of the printing medium 2 is reached, printing on the printing medium 2 is completed and this flow ends.

  Here, the effects of the ink jet printer 5 according to the second embodiment are summarized as follows. The front / rear drive device 80 ′ allows the right UVLED unit 70 </ b> R and the left UVLED unit 70 </ b> L to be positioned at different front / rear positions on the carriage 63. For this reason, for example, one UVLED unit can be positioned on the left and right sides of the print head 62, and the other UVLED unit can be slid and positioned on the rear side to perform printing by irradiating ultraviolet rays. Immediately after adhering to the printing medium 2 by controlling the intensity of the ultraviolet rays to be irradiated after being positioned in this way, for example, by irradiating the UVLED unit located on the left and right sides of the print head 62 with ultraviolet rays for temporary curing. By temporarily curing the UV ink, it is possible to prevent the UV inks from being mixed or mixed. The temporarily cured UV ink is irradiated with UV light for main curing from the UVLED unit that is slid rearward in the left-right reciprocation after the printing unit 60 is moved forward by the front-rear drive mechanism 59. It is fully cured. Therefore, the UV ink is fully cured after a time has elapsed after being temporarily cured, and can be sufficiently smoothed during this time. Therefore, it is possible to fix the UV ink on the surface of the printing medium 2 in a smoothed state so as not to spread and improve the printing quality.

  In the above-described embodiment, the right UVLED unit 70R and the left UVLED unit 70L are not limited to the configuration that is slid in the front-rear direction. For example, as shown in FIG. 9A, a configuration in which each UVLED unit is slidably moved away from the print head 62 in the left-right direction is also possible. With this configuration, the time interval from when the UV ink adheres to the print medium 2 until the ultraviolet rays are irradiated can be changed, so that it depends on the room temperature, the type of the UV ink, the type of the print medium 2, and the like. It becomes possible to irradiate ultraviolet rays at an optimal timing. Further, for example, as shown in FIG. 9B, a configuration is also possible in which each UVLED unit is slidably moved away from the print head 62 rearward and in the left-right direction (diagonally rearward). When configured in this manner, the time interval from when the UV ink adheres to the print medium 2 to when the UV ink is irradiated can be long, so that the UV ink is reliably smoothed during this time. Further, since each UVLED unit is separated from the print head 62 so as to be obliquely rearward, for example, a part of ultraviolet rays irradiated from each UVLED unit is reflected on the surface of the print medium 2 and irradiated to the nozzle. It is possible to reduce “nozzle clogging”. Further, the effect of reducing the clogging of the nozzle can be said even when the nozzle is moved as shown in FIG.

  In the second embodiment described above, as shown in FIG. 7A, the right UVLED unit 70R and the left UVLED unit 70L are slid so as to be able to irradiate the printing line 2a or the printed line 2b with ultraviolet rays. It is not limited to the configuration to be moved. For example, a configuration in which the printed line 2c adjacent to the back of the printed line 2b is slid so as to be able to irradiate ultraviolet rays is also possible. If comprised in this way, the time interval from UV ink adhering to the printing medium 2 until it is irradiated with ultraviolet rays can be made longer, and during this time, the UV ink is reliably smoothed. For this reason, even when the viscosity of the UV ink is extremely high, for example, it can be cured by being irradiated with ultraviolet rays in a smoothed state and fixed to the print medium. The same applies to the first embodiment.

  Further, in the above-described first and second embodiments, the UV irradiation control of the right UVLED unit 70R and the left UVLED unit 70L is performed by irradiating the UV ink attached to the printing medium 2 with the UV light for temporary curing. After that, irradiation control may be performed so that the main curing is performed, and the method is not limited to the above-described control method.

  In the first and second embodiments described above, the ultraviolet rays emitted from the right UVLED unit 70R and the left UVLED unit 70L have two levels of intensity for temporary curing or main curing, but are not limited to this configuration. For example, a configuration in which the intensity of ultraviolet rays is controlled in three or more stages may be employed, or a configuration in which the intensity of ultraviolet rays is continuously controlled may be employed.

  In the first and second embodiments described above, the right UVLED unit 70R and the left UVLED unit 70L are configured to slide back and forth by a servo motor, but are not limited to this configuration. For example, a configuration in which each UVLED unit is slid back and forth using an air cylinder may be used. Furthermore, for example, by using two air cylinders, each UVLED unit can be independently slid back and forth.

  In the first and second embodiments, the case where the print head 62, the right UVLED unit 70R, and the left UVLED unit 70L are mounted on the carriage 63 has been described as an example. However, the present invention is not limited to this configuration. If the right UVLED unit 70 </ b> R and the left UVLED unit 70 </ b> L can be independently moved relative to the print head 62, they are not necessarily mounted on the carriage 63. That is, the print head 62, the right UVLED unit 70R, and the left UVLED unit 70L may be supported by, for example, the guide rail 52 independently so as to be relatively movable.

  In Examples 1 and 2 described above, when the viscosity of the UV ink corresponding to the detected room temperature is obtained, and the time required for smoothing is obtained based on the viscosity of the UV ink (see step 2 in FIG. 10). However, it is not always necessary to obtain the time required for smoothing. For example, an “indoor temperature-smoothing time correspondence table” that associates the room temperature with the time required for smoothing according to the viscosity of the UV ink is stored in the memory of the controller 23 as a database, and the detected room is detected. You may comprise so that smoothing time may be calculated | required directly with reference to a database from temperature.

  Furthermore, in the above-described first and second embodiments, the print medium 2 is fixedly held on the vacuum table 12a (so-called flat bed). However, the present invention is not limited to this configuration. In addition, by additionally providing a winding mechanism, the present invention can be applied to an ink jet printer that performs printing while transporting a sheet-like print medium.

1 is a perspective view showing an ink jet printer according to the present invention. FIG. 3 is a perspective view showing the inside (partially omitted) of the printing unit according to the first embodiment. (A) is the top view of the printing unit which showed the state by which each UVLED unit was slid back, (b) is a top view of the printing unit when not printing. FIG. 4 is a plan view for explaining an operation when performing printing using the printing unit according to the first embodiment, where (a) shows the first pass and the third pass, and (b) shows the second pass and the fourth pass. The pass is shown. FIG. 4 is a plan view for explaining an operation when performing printing using the printing unit according to the first embodiment, where (a) shows the first pass and the third pass, and (b) shows the second pass and the fourth pass. The pass is shown. FIG. 6 is a plan view showing a printing unit according to a second embodiment, where (a) is a plan view of the printing unit showing a state in which the left UVLED unit is slid rearward, and (b) is not performing printing. It is a top view of the printing unit at the time. It is a top view for demonstrating the action | operation at the time of performing printing using the printing unit which concerns on a 2nd Example, (a) is 1st pass and 3rd pass, (b) is 2nd pass and 4th. The pass is shown. It is sectional drawing which showed the process in which UV ink was piled up for every pass in order from (a) to (d). It is the top view which showed the printing unit of another Example. 3 is a flowchart illustrating a printing method according to the present invention. (A) is a plan view showing a conventional printing unit, (b) is a cross-sectional view showing a state in which another UV ink adheres onto a completely cured UV ink, and (c) It is sectional drawing which showed the state which another UV ink adhered on the UV ink which is not hardened | cured.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet printer 2 Print medium 12a Vacuum table (medium support member)
60 Printing unit 62 Printing head 63 Carriage 70R Right UVLED unit (ultraviolet irradiation device)
70R Left UVLED unit (ultraviolet irradiation device)
80 Front / rear drive device (device moving means)

Claims (8)

A medium support member for supporting the print medium;
A print head that ejects and adheres ink toward the surface of the print medium supported by the medium support member;
In an inkjet printer having an ultraviolet irradiation device that cures ink adhered to the surface of the print medium by irradiating the surface of the print medium supported by the medium support member with ultraviolet rays,
The ultraviolet irradiation device includes a first ultraviolet irradiation light source on one side of the print head and a second ultraviolet irradiation on the other side in a first direction in which the print head is reciprocally moved relative to the print medium. With a light source ,
With the first second of the first and second possible apparatus constituted moving means be positioned independently move the respective UV irradiation light source in a direction perpendicular to the direction,
A control means for controlling the irradiation morphism ultraviolet intensity of each of the first and second ultraviolet irradiation source,
The control means controls the first and second ultraviolet irradiation light sources to irradiate the ink adhering to the surface of the print medium with ultraviolet rays for pre-curing to harden the ink in a gel state, and to the temporarily-cured ink. And a control for irradiating the main curing ultraviolet ray for main curing ,
By changing the positional relationship of the first and second ultraviolet irradiation light sources using the apparatus moving means, the irradiation timing between the irradiation of the temporary curing ultraviolet rays and the irradiation of the main curing ultraviolet rays is controlled. An ink jet printer configured to perform the above . The print head and the ultraviolet irradiation device are mounted on a carriage that is moved relative to a print medium in a state of facing the medium support member,
The apparatus moving means is configured to be able to move and position each of the first and second ultraviolet irradiation light sources independently in the second direction on the carriage. Item 10. The inkjet printer according to Item 1. The carriage is reciprocated relative to the print medium in the first direction and relatively moved in the second direction;
The apparatus moving means positions each of the first and second ultraviolet light sources in one of a position adjacent to the print head in the second direction and a position protruding away from the print head. The ink-jet printer according to claim 2 , wherein the ink-jet printer is configured to be capable of. Wherein both sides of the ultraviolet radiation source, according to any one of claims 1, characterized in that the irradiation intensity of ultraviolet light is capable of setting at least the two steps for the curing and for temporary curing 3 Inkjet printer. The inkjet printer according to claim 4 , wherein the ultraviolet irradiation light sources on both sides are configured using light emitting diodes. The control means applies the newly ejected ink to the newly ejected ink from the first and second ultraviolet light sources so that the print head can eject the newly cured ink on the temporarily cured ink. 6. The ink jet printer according to claim 1 , wherein the ink jet printer is configured to be capable of being controlled to irradiate ultraviolet rays for temporary curing . It is a printing unit used to discharge and adhere ink to the surface of the print medium while moving relative to the surface of the print medium, and to cure the attached ink by irradiating it with ultraviolet rays. There,
A print head that ejects and adheres ink toward the surface of the print medium;
A first ultraviolet irradiation light source on one side of the print head and a second ultraviolet irradiation light source on the other side in a first direction which is a direction in which the print head is reciprocally moved relative to the printing medium; An ultraviolet irradiation device that cures ink adhered to the surface of the print medium by irradiating the surface thereof with ultraviolet rays;
A second of said first and second ultraviolet radiation independently by moving the light source is configured to be able to position the device moving means in a direction perpendicular to the front Symbol first direction,
And control means for controlling the irradiation morphism ultraviolet intensity of each of the first and second ultraviolet irradiation source,
The control means controls the first and second ultraviolet irradiation light sources to irradiate the ink adhering to the surface of the print medium with ultraviolet rays for pre-curing to harden the ink in a gel state, and to the temporarily-cured ink. The temporary curing is performed by changing the positional relationship between the first and second ultraviolet irradiation light sources using the apparatus moving means so as to perform a control for irradiating the ultraviolet for the main curing to perform the main curing. A printing unit configured to control irradiation timings of irradiation of ultraviolet rays for use and irradiation of ultraviolet rays for the main curing . A medium support member that supports the print medium, a print head that ejects ink onto the surface of the print medium supported by the medium support member, and the print head reciprocally moves relative to the print medium. a first ultraviolet irradiation light source on one side of the print head in a first direction is a direction, a second ultraviolet irradiation light source on the other side, a second direction perpendicular to the front Symbol first direction The first and second ultraviolet irradiation light sources are printing methods using an inkjet printer configured to include an apparatus moving means configured to be able to move and position each independently. And
Positioning the first and second ultraviolet irradiation light sources at predetermined positions by the apparatus moving means;
The print medium supported by the medium support member performs desired printing by ejecting ink from the print head onto the surface of the print medium and irradiating ultraviolet rays from the first and second ultraviolet irradiation light sources. Curing the ink adhering to the surface of the print medium,
In the step, when performing desired printing by discharging ink from the print head to the surface of the print medium while relatively reciprocating the print head in the first direction,
It was closed and the step of irradiating the step of irradiating ultraviolet rays for temporary curing to cure a gel, the ultraviolet light for curing the ink is temporarily cured ink adhering to the surface of the print medium, the apparatus By changing the positional relationship between the first and second ultraviolet irradiation light sources using a moving means, the irradiation timing between the irradiation of the temporary curing ultraviolet light and the irradiation of the main curing ultraviolet light is controlled. A printing method, wherein printing is performed .

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