JP2007090689A - Ink-jet image forming device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink-jet image forming device which is equipped with a defective ink ejection recovery means for efficiently cleaning a nozzle surface of an ink-jet head and eliminating clogging etc. of nozzles, even if an active ray crosslinking ink is employed. <P>SOLUTION: The ink-jet image forming device uses at least the active ray crosslinking ink, and is equipped with the defective ink ejection recovery means for wiping the ink-jet head and an area near the nozzles of the ink-jet head. Herein the defective ink ejection recovery means is provided with a light source for applying active rays to the area near the nozzles, and the wiping of the area near the nozzles after ejection of the ink from the nozzles of the ink-jet head, is carried out after application of the active rays from the light source to the area near the nozzles. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an inkjet image forming apparatus that uses an actinic ray crosslinkable ink that is water-based and includes an ink ejection failure recovery means that can efficiently remove residual ink adhering to the nozzle head surface of the inkjet head. Relates to the device.

  2. Description of the Related Art An inkjet image recording apparatus that prints or prints on a support by ejecting and flying ink droplets while reciprocating an inkjet head having a plurality of nozzles to the left and right is well known.

  Further, in the ink jet recording apparatus, a cap unit for preventing clogging of the nozzles due to ink drying in the nozzles of the ink jet head, a cleaning unit for removing residual ink on the nozzle surface after ink ejection, for example, by wiping, etc. It is also known that maintenance means are provided.

  Ink droplets remaining on the nozzle surface of the ink jet head, particularly in the vicinity of the nozzle, cause landing deviation of the ink or cause nozzle clogging when solidified.

  As a means for cleaning the nozzle surface of the head, generally, wiping with a blade or the like is often performed to remove residual ink droplets. However, there are various factors such as ink composition (ink surface tension), blade material, wiping speed, etc., and these adjustments enable ink removal and keep the nozzle surface in a constant state, and stable ejection of inkjet ink. Secured.

  On the other hand, unlike conventional inks, there has been proposed an ink that contains a water-based ultraviolet polymerization monomer, is aqueous, and is crosslinked (or polymerized) / cured by ultraviolet rays (see Patent Document 1).

  These ultraviolet-crosslinkable inks are crosslinked and cured on a recording medium, so that even when recording on plain paper, the feathering is good and the ink absorption is low. No image or color bleed, and gives an image excellent in scratching, water resistance, gloss, fading, etc.

For these inks, the same maintenance means as described above are necessary, but these inks are crosslinkable (polymerizable), and the residual ink is gradually cured, so that the head is easily clogged. There is a need for a means for recovering defective ink discharge that efficiently removes residual ink and prevents stable head clogging and the like and that can maintain stable discharge.
JP-A-7-224241

  Accordingly, an object of the present invention is to use an actinic ray crosslinkable ink, and even when these inks are used, the nozzle surface of the ink jet head can be efficiently cleaned and the nozzles are not clogged. An object of the present invention is to provide an inkjet image forming apparatus provided with ejection failure recovery means.

  The above object of the present invention is achieved by the following means.

  1. At least energy generating means for ink ejection using an actinic ray crosslinkable ink, an ink jet head having a nozzle for ejecting ink, an electric circuit for supplying a drive signal for the ink jet head, and a wiping operation in the vicinity of the nozzle of the ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for performing the ink discharge failure recovery means, the ink discharge failure recovery means includes a light source for irradiating actinic rays in the vicinity of the nozzle, and discharges ink from the nozzle of the ink jet head. The inkjet image forming apparatus according to claim 1, wherein the wiping operation in the vicinity of the nozzle is performed after irradiating an actinic ray from the light source in the vicinity of the nozzle.

  2. At least energy generating means for ink ejection using an actinic ray crosslinkable ink, an ink jet head having a nozzle for ejecting ink, an electric circuit for supplying a drive signal for the ink jet head, and a wiping operation in the vicinity of the nozzle of the ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for performing the ink discharge failure recovery means, the ink discharge failure recovery means includes a light source for irradiating actinic rays in the vicinity of the nozzle, and discharges ink from the nozzle of the ink jet head. In the inkjet image forming apparatus, the wiping operation in the vicinity of the nozzle is performed simultaneously with the irradiation of the actinic ray from the light source in the vicinity of the nozzle.

  3. At least using actinic ray crosslinkable ink, energy generating means for ink discharge, ink jet head having nozzle for discharging ink, electric circuit for supplying ink jet head drive signal, and ink transfer in the vicinity of nozzle of ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for transferring and removing the residual ink from the vicinity of the nozzle by pushing the member and then performing the peeling operation, the ink discharge failure recovery means is activated near the nozzle. Transferring and removing residual ink from the vicinity of the nozzle by the ink ejection failure recovery means, which is performed after the ink is ejected from the nozzle of the inkjet head, is provided in the vicinity of the nozzle. After irradiating actinic rays from the light source Inkjet image forming apparatus characterized by dividing.

  4). At least using actinic ray crosslinkable ink, energy generating means for ink discharge, ink jet head having nozzle for discharging ink, electric circuit for supplying ink jet head drive signal, and ink transfer in the vicinity of nozzle of ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for transferring and removing the residual ink from the vicinity of the nozzle by pushing the member and then performing the peeling operation, the ink discharge failure recovery means is activated near the nozzle. The ink transfer member is provided with a light source for irradiating a light beam, and the ink transfer member removes residual ink from the vicinity of the nozzle by the ink discharge failure recovery means, which is performed after the ink is discharged from the nozzle of the inkjet head. Front from the light source provided on the back side Inkjet image forming apparatus which comprises carrying out later irradiated with active light rays in the vicinity of the nozzle.

  5. 5. The inkjet image forming apparatus according to any one of 1 to 4, wherein the actinic ray crosslinkable ink has at least a colorant, water, and a plurality of side chains in a hydrophilic main chain, and an active energy ray. An ink-jet image forming apparatus comprising: a polymer compound capable of crosslinking between side chains by irradiation of

  According to the present invention, beading or color bleed is performed even on a medium that uses water-based actinic-light-crosslinkable ink and has good feathering when recording on plain paper and has little or no ink absorbability. Inkjet image forming apparatus that can perform high-quality inkjet recording, has good inkjet head cleaning efficiency, and does not disturb the image due to ink landing deviation, lack of ink, ejection failure, etc. for long-term use can get.

  Hereinafter, the best mode for carrying out the present invention will be described, but the present invention is not limited thereto.

  The present invention provides at least capping in the vicinity of the nozzles (nozzle surface) of the inkjet head, which is performed after discharging ink from the nozzles of the inkjet head as a maintenance means in an inkjet image forming apparatus using at least actinic ray crosslinkable ink. In the ink discharge failure recovery means comprising suction and suction, and cleaning with a blade or transfer member (for example, wiping with a blade), at least when the nozzle surface is cleaned with the blade or transfer member, the ink remaining on the nozzle surface is This is performed after irradiation with actinic rays and gelation.

  The actinic ray crosslinkable ink according to the present invention has a plurality of side chains in at least a coloring material, water, and a hydrophilic main chain, and can be crosslinked between the side chains by irradiating active energy rays. It is an ink containing a polymer compound, but after printing on the recording medium by main scanning of the head, it is immediately fixed on the recording medium by being irradiated with actinic rays, crosslinked and gelled. Although it easily gives an image with little bleeding or the like, since this ink is crosslinkable, if ink remains on the nozzle surface of the ink jet head, it gradually crosslinks and solidifies, so that stains that are difficult to remove are likely to occur.

  A water-repellent surface is usually used on the nozzle surface of the inkjet head to repel water-based ink so that the nozzle surface does not get wet and to return ink from the outer surface of the nozzle to the inside of the nozzle quickly when ink is ejected. It is done. This is also because the ink droplets can be easily cleaned by the blade.

  For example, in order to make the nozzle surface water repellent, eutectoid plating with nickel ion and water repellent fluorine-containing polymer resin particles such as polytetrafluoroethylene, polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoro, etc. A method of coating a fluorine-containing resin such as a propylene copolymer (FEP) or a silicone resin (described in JP-B-52-24821, JP-A-56-2862, JP-A-57-72866, etc.), Treatment with reactive silane compound (Japanese Patent Laid-open No. Sho 56-89569), having a polymer-containing film having a fluorine-containing heterocyclic structure (Japanese Patent Laid-Open No. Hei 4-221959), radical polymerizable unsaturated via a urethane bond A fluoropolymer having a bond, one-end radical-polymerizable polysiloxane, and a radical-polymerizable monomer. There is provided a coating composition (JP 2002-225274) or the like comprising a graft copolymer and a curing agent comprising engaged. As the water repellency of the nozzle surface, the contact angle with the ink used is preferably 60 ° or more.

  The blade used for cleaning is usually made of a flexible material such as urethane rubber, silicon rubber, fluorine rubber, olefin rubber such as EPDM, or diene rubber such as isoprene or chloroprene in order to increase the removal efficiency. Is done.

  However, when a crosslinkable ink is used, not only solidification by evaporation but also solidification by crosslinking and polymerization proceeds at the same time. The isohigh viscosity component does not re-dissolve and may remain on the nozzle surface. When such dirt adheres to the nozzle surface, the water repellency is lost in the dirt-attached portion, and the nozzle surface that should be kept water-repellent further increases the dirt. In particular, when this occurs in the vicinity of the nozzle, ink landing deviation, ink shortage, and the like occur, and thus sufficient cleaning is required for a long period of time.

  That is, as in the case of conventional inks having no crosslinkability, ink droplets are likely to remain by simply wiping with a blade or a cleaning method using a transfer member such as cloth (cloth).

  The present inventor has found an ink discharge failure recovery means that can perform sufficiently stable cleaning even when these crosslinkable inks are used.

  That is, when the present inventors use a crosslinkable water-based ink, the state immediately after irradiation with actinic rays (for example, ultraviolet rays) is in a polymer compound gel (network structure) crosslinked between side chains. This is a state in which ink components such as coloring materials are contained, and among them, the amount of water as a solvent is the largest, and it is considered that a water-containing gel is formed. The ink droplets immediately after being irradiated with ultraviolet rays are wiped with a blade or other removal means in the form of a soft jelly-like gel, or other removal means, for example, transferring / removing the transfer material, etc. Rather, it was found that ink droplets did not remain on the nozzle surface and the removal efficiency was good. This is considered to be because the whole is removed together while the ink is soft due to the crosslinking of the ink.

  Next, an example of the ink jet image recording apparatus according to the present invention will be described.

  The image recording apparatus used in the present invention includes an energy generating means for ejecting ink, an ink jet head having an ink ejecting nozzle, an electric circuit for supplying a drive signal for the ink jet head, and an actinic ray irradiation light source for ink bridging In addition, the image recording unit provided with the above, an ink discharge failure recovery means (also referred to as maintenance means) for ensuring stable ink discharge, and solidification due to ink evaporation or the like occurs at the standby position when the inkjet head is not in use. Capping means for covering the nozzle surface with a cap member so as not to be present.

  FIG. 1 is a schematic diagram showing the overall configuration of the ink jet recording apparatus according to the present invention.

  The image recording unit 1 is disposed horizontally and has a platen 7 that sucks and supports the back surface (the surface opposite to the image forming surface side) of the recording medium in a predetermined range on the upper surface by driving a suction device, and inkjet Ink jet head 2 having a circuit (not shown) for supplying an electric signal for driving the head, an energy generating means (not shown) for discharging ink, and a nozzle for discharging ink toward a recording medium, and these ink jets A head 2 and an irradiation means 3 having an active light source are mounted, a carriage 4 that moves in the scanning direction during image formation, and a carriage 4 that is mounted on the carriage and that drives the carriage along the scanning direction during printing. A drive circuit board (not shown), a guide member (linear guide) 5 extending along the scanning direction and guiding the movement of the carriage, and extending along the scanning direction A linear scale having an optical pattern disposed in the longitudinal direction thereof, a linear encoder sensor mounted on the carriage and reading the optical pattern disposed on the linear scale and outputting it as a clock signal, etc. (all not shown) Consists of.

  In the image forming apparatus according to the present invention, the member to be used is preferably a member having a low transmittance or reflectance with respect to the active energy ray in order to prevent irradiation of the active energy ray, for example, the head surface due to irregular reflection of ultraviolet rays.

  In the image recording unit 1, the ink jet head 2 held by the carriage 4 has an image forming surface of the recording medium P conveyed on the platen 7 and a nozzle surface on which the ejection ports of the ink jet head 2 are formed during image recording. Are arranged so as to face each other, and ink is supplied to each head from a cartridge for recording ink through a tube for piping. A plurality of heads are provided as required, and four heads are shown here (for four colors Y, M, C, and K). For example, six colors for CMK shades and Y, and colorless ink are used. When used, eight ink-jet heads are provided. Irradiation means 3 having active energy rays is provided on both sides of the head.

  In the image recording unit 1, the platen unit 7 has a function of absorbing ultraviolet rays and absorbs extra ultraviolet rays that have passed through the recording material P. As a result, a high-definition image can be reproduced very stably.

  The recording medium P is guided by a guide member (not shown), and moves in the forward direction (arrow) from the back in FIG. 1 by the operation of a conveying means (not shown). The ink jet head scanning means (not shown) scans the ink jet head 2 held by the carriage 4 by reciprocating the carriage 4 along the guide member (linear guide) 5 in the Y direction in FIG.

  The carriage 4 is installed on the upper side of the recording medium P, and a plurality (four in this case) of inkjet heads 2 to be described later are arranged according to the number of colors used for image printing on the recording medium P, and the ejection ports are arranged on the lower side. And store. The carriage 4 is installed in the image recording unit 1 so as to reciprocate in the Y direction in FIG. 1, and reciprocates in the Y direction in FIG. 1 by driving the head scanning means.

  The ink jet head 2 ejects ink jet ink supplied by an ink supply means (not shown) from a discharge port toward the recording medium P by operation of a plurality of discharge means (not shown) provided therein. To do. The ink jet ink ejected by the ink jet head 2 is composed of a polymer compound that can be cross-linked between side chains by irradiating actinic rays, and crosslinks and cures when irradiated with actinic rays.

  The inkjet head 2 is a certain area (landing possible area) in the recording medium P during the scan in which the head scanning means moves from one end of the recording medium P to the other end of the recording medium P in the Y direction in FIG. Ink jet ink is ejected as ink droplets to land on the landable area.

  The above scanning is performed as many times as necessary, and after the ink jet ink is ejected toward one landable area, the recording medium P is appropriately moved from the back to the front in FIG. While performing scanning, the inkjet head 2 discharges ink jet ink to the next landable area adjacent in the depth direction in FIG.

  An image is formed on the recording medium P by repeating the above operation and ejecting ink jet ink from the ink jet head 2 in conjunction with the head scanning means and the conveying means.

  There are various types of actinic rays such as electron beams, alpha rays, ultraviolet rays, and visible light as crosslinking and curing ink jet inks. In the present invention, ultraviolet rays are most preferred.

  The irradiation means 3 includes an ultraviolet lamp that emits ultraviolet light in a specific wavelength region with stable exposure energy and a filter that transmits ultraviolet light of a specific wavelength. For example, a belt-shaped metal halide lamp is used as the ultraviolet lamp and paper.

  The irradiating means 3 has the same shape as the largest one that can be set by the image recording unit 1 among the landable areas where the ink jet head 2 ejects ink for ink jet by a single scan driven by the head scanning means, or can land. It has a shape larger than the region.

  The irradiation means 3 is fixed on both sides of the carriage 4 so as to be substantially parallel to the recording medium P.

  As described above, as a means for adjusting the illuminance of the ink discharge portion, the entire ink jet head 2 is shielded, but in addition, the ink discharge of the ink jet head 2 is determined from the distance h1 between the irradiation means 3 and the recording medium P. It is effective to increase the distance h2 between the head and the recording medium P (h1 <h2), or to increase the distance d between the inkjet head 2 and the irradiation means 3 (d is increased). Moreover, it is preferable to make a bellows structure between the ink jet head 3 and the irradiation means 3.

  Here, the wavelength of the ultraviolet rays irradiated by the irradiation means 3 can be changed as appropriate by replacing the ultraviolet lamp or filter provided in the irradiation means 3.

  The actinic ray used in the present invention is most preferably ultraviolet rays.

In the case of using ultraviolet rays, as a light source, in addition to the above, for example, low pressure, medium pressure, high pressure mercury lamps having an operating pressure of several hundred Pa to 1 MPa, xenon lamps having a light emission wavelength in the ultraviolet region, cold cathode tubes, heat A conventionally well-known thing, such as a cathode tube and LED, is used. A cold cathode tube, a hot cathode tube, a mercury lamp or a black light is also preferred. A low-pressure mercury lamp, a hot cathode tube, a cold cathode tube, and a germicidal lamp that emit ultraviolet light having a wavelength of 254 nm are preferable because they can effectively prevent bleeding and control the dot diameter. When performing ultraviolet irradiation, ultraviolet irradiation dose, 100 mJ / cm ² or more, preferably 500 mJ / cm ² or more, also, 10,000 / cm ² or less, preferably performed at 5,000 mJ / cm ² or less in the range . If it is the amount of ultraviolet irradiation within this range, a sufficient curing reaction can be carried out.

  As the irradiation condition of the active energy ray, it is preferable that the active energy ray is irradiated within 0.001 to 1.0 seconds after ink landing, and more preferably 0.001 to 0.5 second.

  In order to form a high-definition image, it is particularly important that the irradiation timing is as early as possible. Therefore, it is preferable that the irradiation means 3 is equipped with a shutter. For example, when using ultraviolet rays, the ratio of illuminance when opening and closing the shutter is preferably shutter open / shutter close = 10 or more, more preferably 100 or more. More preferably, it is 10,000 or more.

  The inkjet head used is an electro-mechanical conversion system (for example, single cavity type, double cavity type, bender type, piston type, shear mode type, shared wall type, etc.), electro-thermal conversion system. (For example, thermal ink jet type, bubble jet (registered trademark) type, etc.), electrostatic suction type (for example, electric field control type, slit jet type, etc.) and discharge type (for example, spark jet type, etc.). . The electro-mechanical conversion method is preferable, but any discharge method may be used.

  In the ink jet image recording apparatus according to the present invention, the maintenance unit 8 provided with the ink discharge failure recovery means includes a suction cap 81, a blade 82, an ultraviolet light source, and the like provided to face the nozzle surface. Here, it has the structure which has the window 83 which irradiates the light from an actinic-light light source to a nozzle surface.

  The suction cap performs ink suction by an appropriate suction means (for example, a suction pump) and forcibly discharges ink from the ink discharge port, thereby removing, for example, thickened ink in the nozzle and performing discharge recovery processing.

  The actinic light source provided in the maintenance unit is not shown in FIG. 1, but here, the actinic light (ultraviolet light) is irradiated onto the nozzle surface through an irradiation window 83 formed on the maintenance unit base. As a result, the ink remaining on the nozzle surface is crosslinked and becomes a crosslinked gel state containing water.

  Further, after the discharge recovery process, the blade is irradiated with actinic rays on the nozzle surface of the head, and then the blade is protruded into the movement path of the head to perform the wiping operation of the nozzle surface.

  The blade used for cleaning is made of a flexible material such as urethane rubber or silicon rubber in order to increase the removal efficiency.

  For example, at the start of printing, the carriage 4 moves until the nozzle surface of the inkjet head 2 comes to a position just opposite to the suction cap 81 provided to face the nozzle surface in the maintenance unit 8. Next, the suction cap 82 comes into close contact with the nozzle surface and sucks ink from the nozzles of the inkjet head 2. After sucking ink, the carriage moves until the nozzle surface of the inkjet head 2 reaches the irradiation window 83 position, and the nozzle surface is irradiated with ultraviolet rays through the irradiation window 83. Further, the blade 82 wipes the nozzle surface of the inkjet head 2 by the movement of the carriage, thereby wiping and removing ink droplets adhering to the nozzle surface and performing an ink ejection recovery operation to recover the print quality. Incidentally, either the carriage or the maintenance unit may actually move, and the movement may be relative.

  The carriage 4 moves to the home position 9 after printing (recording) is finished or when the inkjet image recording apparatus is not used, and the provided cap 91 covers the nozzle surface (nozzles) of the inkjet head 2. Light shielding is also performed, and during the standby period, ink is bridged in the vicinity of the nozzles, and the solvent is prevented from evaporating and solidifying the ink.

  The ink ejection recovery operation by the cleaning operation of the inkjet head is performed by removing ink remaining in the vicinity of the nozzle by a cleaning member such as a blade after the ink is sucked by the suction cap 82. In the present invention, the nozzle surface Before cleaning (near the nozzle), actinic light irradiation is first performed. Thereafter, the cleaning member performs an operation of removing the ink in a crosslinked gel state. The actinic rays are preferably the same as those used for the irradiation means used for crosslinking and curing the ink in the image recording unit 1. Therefore, ultraviolet rays are preferable, and a metal halide lamp or the like can be similarly used.

  Hereinafter, some preferred actual cleaning means (and an inkjet image forming apparatus having the same) combined with irradiation of actinic rays on the nozzle surface of the inkjet head according to the present invention will be described with reference to the drawings.

  FIG. 2 shows a state where the elastic blade 82 wipes the nozzle surface of the inkjet head as viewed from the nozzle surface 21 side (recording medium) of the inkjet head 2. For simplicity, only one inkjet head is shown, and only the cleaning member such as the inkjet head and the blade is shown, and the support member, the drive system, etc. are omitted.

  FIG. 2A shows a state in which ultraviolet rays are applied to the nozzle surface (near the nozzle) of the inkjet head that is soiled by the adhesion of ink droplets.

  In the ink jet image recording apparatus shown in FIG. 1, actinic rays (for example, ultraviolet rays) are irradiated from an irradiation window 83 provided adjacent to the blade 82 of the maintenance unit 8, on the nozzle surface of the opposing ink jet head. The residual ink is crosslinked and gelled. Although the light source is not shown, the nozzle surface is irradiated with the irradiation energy necessary to cause ink cross-linking and gelation at the same level as the amount of energy applied to the ink droplets on the recording medium after printing in combination with the shutter. Is done.

Next, wiping (sweep) of the nozzle surface (near the nozzle) of the inkjet head is performed by a blade 82 made of a flexible material such as urethane rubber (FIGS. 2B and 2C). Thus, the crosslinked and gelled ink is efficiently removed from the vicinity of the nozzle (FIG. 2D). The wiping operation is performed by the relative movement of the maintenance unit and the carriage. Either one can move.

  FIG. 3 also shows a method using a blade, but wiping is performed while irradiating actinic rays instead of wiping with a blade after irradiation with actinic rays. 3 (a), (b), and (c) and the movement of the blade as the wiping progresses are illustrated. In this case, as described above, the irradiation from the irradiation window opened on the support member of the maintenance unit adjacent to the blade may be continued, but the blade support portion is integrally provided with an actinic ray irradiation window. A structure is installed so that an unnecessary part other than the nozzle surface (near the nozzle) is not irradiated with actinic rays, and an irradiation window is formed integrally with the blade, and actinic rays are irradiated while moving with the blade. And a method of performing cleaning at the same time is preferable. In any of the methods, when light with too high illuminance is applied, evaporation of the solvent or the like occurs, and when it becomes a hard gel, it becomes difficult to remove ink. Therefore, conditions suitable for ink removal are obtained by testing.

  After the nozzle surface is swept by the blade, the maintenance unit to which the blade is fixed moves to a position where the blade is separated from the nozzle surface, and further returns from the position facing the head to the standby position. The dirt wiped off by the blade is performed by using a second cleaning member, for example, by scouring with another blade, or by absorbing the dirt with a porous member (for example, non-woven fabric).

  Next, FIG. 4 shows a cleaning method using a cleaning roll. The cleaning roll support member, drive system, timing circuit, etc. are not shown, but instead of the blade, they are provided in the maintenance unit and moved to a position facing the nozzle surface of the head by the movement of the maintenance unit. Then, the ink droplet or the cross-linked gel adhering to the nozzle surface in contact with the nozzle surface is transferred to a cleaning roll to remove dirt from the nozzle surface (near the nozzle) of the inkjet head.

  As the material of the cleaning roll, since the nozzle surface is formed of a water-repellent material, a silicone rubber roll, a fluorine resin roll, etc., and a resin roll such as polyethylene, polyethylene terephthalate, polycarbonate, nylon, polyamide, etc. are preferably used. In the case of the material having hydrophobicity, gelled ink droplets after irradiation with actinic rays are easily transferred from the nozzle surface, and dirt is easily removed during cleaning of the cleaning roll itself (for example, blades). Scraping with a). In FIG. 4A, after receiving the actinic ray, for example, the cleaning roll moves to the transfer position on the nozzle surface, and is pressed against the nozzle surface to move while contacting and rotating, thereby transferring dirt. (FIG. 5 (b)) When the movement on the nozzle surface is completed, the transfer roll is separated from the nozzle surface by being lowered, scraped by a secondary cleaning member, for example, a blade, contacted with the secondary roll, etc. Then, the ink smudge transferred onto the roll is removed by wiping with a non-woven fabric or the like, and then returned to the standby position of the maintenance unit and waits until the next ink discharge recovery operation (leaning).

  As the cleaning roll, a liquid-absorbing cleaning roll as described in JP-A-2004-1114619 can be used. Examples thereof include a roll formed of a porous material such as porous polyurethane, a non-woven fabric, a felt, a roll having a fiber made of a liquid-absorbing polyester cloth or the like on the surface.

  5A, 5B, and 5C show that the nozzle surface of the head is cleaned by the cleaning roll while irradiating the cleaning actinic ray. As in the case of wiping with a blade, there is a method in which a cleaning roll and an ultraviolet ray irradiation source are integrally formed in a maintenance unit, and the cleaning roll cleans the head nozzle surface while receiving irradiation from the irradiation source. preferable.

  FIG. 6 is for cleaning the nozzle surface of the inkjet head using a sheet-like cleaning member (cleaning cloth).

  The cleaning of the head with the cleaning cloth is described in, for example, JP-A-11-78034 and the like, and a similar mechanism can be used.

  Cleaning with the cleaning cloth is performed as follows, for example. First, the maintenance unit moves to a position facing the nozzle surface, and after irradiating the nozzle surface of the inkjet head with ultraviolet rays from the cleaning active light irradiation window provided in the maintenance unit (FIG. 6A), A maintenance unit equipped with a cleaning member composed of a take-up reel and a take-up reel that supplies a cleaning cloth of a size that just covers the nozzle surface of a sheet (tape or film) is further equipped with a cleaning member that is just the head of the cleaning cloth. It moves until it is set to the position which opposes the nozzle surface (FIG.6 (b)). Alternatively, the head (carriage) may move to a position where the nozzle surface faces the cleaning cloth of the cleaning member.

  Then, the cleaning member rises (in the drawing), and the cleaning cloth is pressed against the nozzle surface of the head to be brought into close contact (FIG. 6C). At this time, the head or the cleaning member may perform a movement (wiping operation) such that the head or the cleaning member is displaced from each other within the same plane. After the contact for a certain period of time, the cleaning cloth descends again to leave the nozzle surface (FIG. 6D). The cleaning member separated from the nozzle further moves to the standby position. The cloth on which the dirt is transferred is taken up on a take-up reel, and a new unused cloth is unwound from the supply reel.

  In this way, due to the close contact of the cleaning cloth, the ink stain is transferred or absorbed from the nozzle surface (near the nozzle) to the cloth, thereby cleaning the head.

As the cleaning cloth, various films (tapes) as described above, for example,
Examples of the resin film include fluororesin, polyethylene, polyethylene terephthalate, polycarbonate, nylon, and polyamide. A material having a lower hydrophobicity than the head surface is preferable because gelled ink droplets after irradiation with actinic rays are easily transferred from the nozzle surface.

  Also, an ink-absorbing cloth, a normal polyester, nylon or other fabric can be used.

  In addition, it is effective to treat these cloths and film surfaces so that contaminants easily adhere to them. Surface modification such as plasma treatment, ultraviolet ray treatment, corona discharge treatment, and surface roughening such as blast treatment are effective. There is processing.

  In addition, the cleaning cloth applies a torque between the take-up reel and the take-out reel to give tension, so that the cloth does not wrinkle and the cloth uniformly contacts the nozzle surface.

  FIG. 7 shows a method in which the head nozzle surface is subjected to cleaning with a cleaning cloth while being irradiated with actinic rays.

The operation of the cleaning member, the cleaning cloth, etc. are the same as in the embodiment shown in FIG. 6, but as shown in FIG. 7C, the cleaning cloth is pressed against the head nozzle surface and irradiated with actinic rays. Is done. As a result, the ink is transferred to or absorbed by the cloth and is cross-linked and gelled. In this case, actinic rays are irradiated from the back surface of the cleaning cloth (opposite side of the nozzle surface) through the cloth.
The actinic ray irradiation source preferably has an integral structure with the cleaning member, and the cloth is preferably smooth and transparent with no light scattering, such as a polyester film (tape). .

  Although the embodiment of the cleaning method of the present invention has been described above, the ink jet recording apparatus using the actinic ray curable ink according to the present invention has any one of these ink discharge recovery means (cleaning means). preferable.

  Next, the actinic ray curable ink that can be used in the present invention will be described.

  The ink-jet ink used in the present invention has at least a colorant, water, and a polymer having a plurality of side chains in a hydrophilic main chain and capable of crosslinking between side chains by irradiation with active energy rays. An ink containing a compound, which is an actinic ray curable ink that crosslinks and cures when irradiated with actinic rays after landing on a recording medium.

  Hereinafter, the components will be described.

  Hereinafter, each component and configuration of the ink according to the present invention will be described in detail.

<Active energy ray crosslinkable polymer compound>
The polymer compound having a plurality of side chains in the hydrophilic main chain according to the present invention and capable of crosslinking between the side chains by irradiating with active energy rays is a saponified product of polyvinyl acetate, polyvinyl acetal, polyethylene Oxide, polyalkylene oxide, polyvinylpyrrolidone, polyacrylamide, polyacrylic acid, hydroxyethyl cellulose, methyl cellulose, hydroxypropyl cellulose, or a derivative of the hydrophilic resin, and at least one hydrophilic selected from the group consisting of these copolymers In the resin, a modified group such as a photodimerization type, a photodecomposition type, a photopolymerization type, a photomodification type, or a photodepolymerization type is introduced into the side chain. Photopolymerizable crosslinkable groups are desirable from the viewpoints of sensitivity and performance of the generated image.

  Further, from the viewpoint of reactivity with the color material to be combined, the side chain is preferably nonionic, anionic, or amphoteric (betaine compound). In particular, when the color material is combined with an anionic dye or an anionic pigment, The chain is preferably nonionic or anionic, particularly preferably nonionic.

  In the hydrophilic main chain, a saponified product of polyvinyl acetate is preferable from the viewpoint of ease of introduction of side chains and handling, and the degree of polymerization is preferably 200 or more and 2000 or less, and more preferably 200 or more and 500 or less. When the degree of polymerization is less than 200, the viscosity increase during the crosslinking reaction is insufficient, and color bleeding and beading may not be sufficiently prevented. On the other hand, if the degree of polymerization exceeds 2000, the viscosity when added to the ink is increased, which may impair the emission stability.

  The modification rate of the side chain with respect to the main chain is preferably 0.3 mol% or more and 4 mol% or less, and more preferably 0.8 mol% or more and 4 mol% or less from the viewpoint of reactivity. If it is less than 0.3 mol%, the crosslinkability is insufficient and the effect of the present invention is reduced. If it is more than 4 mol%, the crosslink density is increased and the film is hard and brittle, and the strength of the film is lowered.

  As the photodimerization-type modifying group, those in which a diazo group, a cinnamoyl group, a stilbazolium group, a styrylquinolium group or the like is introduced are preferable. (Composition).

  The photosensitive resin described in JP-A-60-129742 is a compound represented by the following general formula (1) in which a stilbazolium group is introduced into a polyvinyl alcohol structure.

In the formula, R ₁ represents an alkyl group having 1 to 4 carbon atoms, and A ⁻ represents a counter anion.

  The photosensitive resin described in JP-A-56-67309 includes a 2-azido-5-nitrophenylcarbonyloxyethylene structure represented by the following general formula (2) in the polyvinyl alcohol structure, or the following general formula. This is a resin composition represented by (3) and having a 4-azido-3-nitrophenylcarbonyloxyethylene structure.

  Further, a modifying group represented by the following general formula (4) is also preferably used.

  In the formula, R represents an alkylene group or an aromatic ring. A benzene ring is preferred.

  As the photopolymerization type modifying group, for example, a resin represented by the following general formula (5) shown in JP-A Nos. 2000-181062 and 2004-189841 is preferable from the viewpoint of reactivity.

In the formula, R ₂ represents a methyl group or a hydrogen atom, n represents 1 or 2, X represents — (CH ₂ ) _m —COO— or —O—, and Y represents an aromatic ring or a single bond. And m represents an integer from 0 to 6.

  Moreover, it is also preferable to use the photopolymerization type | mold modified group represented by following General formula (6) described in Unexamined-Japanese-Patent No. 2004-161942 for a conventionally well-known water-soluble resin.

In the formula, R ₃ represents a methyl group or a hydrogen atom, and R ₄ represents a linear or branched alkylene group having 2 to 10 carbon atoms.

  Such an active energy ray-crosslinking resin is preferably contained in an amount of 0.8% by mass to 5.0% by mass with respect to the total mass of the ink. The presence of 0.8% by mass or more improves cross-linking efficiency, and beading and color bleeding are more preferable due to a rapid increase in ink viscosity after cross-linking. In the case of 5.0% by mass or less, it is difficult to adversely affect the physical properties of the ink and the state in the ink head, which is preferable from the viewpoints of light emission properties and ink storage stability.

  In the active energy ray cross-linking resin of the present invention, the main chain having a certain degree of polymerization is cross-linked through a cross-linking bond between side chains, and thus polymerizes through a general chain reaction. The effect of increasing the molecular weight per photon is significantly larger than that of an active energy ray curable resin. On the other hand, in the conventionally known active energy ray curable resins, the number of crosslinking points cannot be controlled, so the physical properties of the cured film cannot be controlled, and the film tends to be hard and brittle.

  In the resin used in the present invention, the number of cross-linking points can be completely controlled by the length of the hydrophilic main chain and the amount of side chains introduced, and the physical properties of the ink film can be controlled according to the purpose.

  Furthermore, almost all of the conventionally known active energy ray-curable inks other than the colorant are curable, so that the dots after curing are raised and inferior in image quality typified by gloss, are used in the present invention. The resin requires only a small amount, and since there are many dry components, the image quality after drying is improved and the fixing property is also good.

(Photopolymerization initiator, sensitizer)
In the present invention, it is preferable to add a photopolymerization initiator or a sensitizer. These compounds may be dissolved or dispersed in a solvent, or may be chemically bonded to the photosensitive resin.

  There is no restriction | limiting in particular about the photoinitiator and photosensitizer which are applied, A conventionally well-known thing can be used.

  Although there is no restriction | limiting in particular about the photoinitiator and photosensitizer which are applied, A water-soluble thing is preferable from a viewpoint of mixability and reaction efficiency. In particular, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone (HMPK), thioxanthone ammonium salt (QTX), and benzophenone ammonium salt (ABQ) are preferable from the viewpoint of miscibility with an aqueous solvent.

  Furthermore, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone (n = 1, HMPK) represented by the following general formula (7) from the viewpoint of compatibility with the resin, The ethylene oxide adduct (n = 2 to 5) is more preferable.

  In the formula, n represents an integer of 1 to 5.

  Other examples include benzophenones such as benzophenone, hydroxybenzophenone, bis-N, N-dimethylaminobenzophenone, bis-N, N-diethylaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone. Thioxanthones such as thioxatone, 2,4-diethylthioxanthone, isopropylthioxanthone, chlorothioxanthone, and isopropoxychlorothioxanthone. Anthraquinones such as ethyl anthraquinone, benzanthraquinone, aminoanthraquinone and chloroanthraquinone. Acetophenones. Benzoin ethers such as benzoin methyl ether. 2,4,6-trihalomethyltriazines, 1-hydroxycyclohexyl phenyl ketone, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di ( m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-phenylimidazole dimer, 2- (P-methoxyphenyl) -4,5-diphenylimidazole dimer, 2, -di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5 -2,4,5-triarylimidazole dimer of diphenylimidazole dimer, benzyldimethyl ketal, 2-benzyl-2-dimethyl Amino-1- (4-morpholinophenyl) butan-1-one, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-1-propanone, 2-hydroxy-2-methyl-1-phenyl -Propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, phenanthrenequinone, 9,10-phenanthrenequinone, Benzoins such as methylbenzoin and ethylbenzoin, 9-phenylacridine, acridine derivatives such as 1,7-bis (9,9'-acridinyl) heptane, bisacylphosphine oxide, and mixtures thereof are preferably used. May be used alone or in combination.

  In addition to these photopolymerization initiators, accelerators and the like can also be added. Examples of these include ethyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethanolamine, diethanolamine, triethanolamine and the like.

  Even if these photoinitiators are grafted to the side chain with respect to the hydrophilic main chain.

(Actinic ray, irradiation method)
The activity is as described above. For example, electron beams, ultraviolet rays, α rays, β rays, γ rays, X-rays, etc. can be mentioned, but there are dangers to the human body, easy handling, and electron rays and ultraviolet rays that are widely used industrially. preferable. The aforementioned ultraviolet light source is preferable.

  The basic method of actinic ray irradiation is also disclosed in Japanese Patent Application Laid-Open No. 60-132767. The light source is provided on both sides of the head unit and the head and light source are scanned by the shuttle method as described above. It is as follows. In addition, US Pat. No. 6,145,979 also discloses a method using an optical fiber and a method of irradiating the recording unit with UV light by applying a collimated light source to a mirror surface provided on the side of the head unit. Has been. Any of these irradiation methods can be used in the image forming method of the present invention.

  It is also preferable to irradiate the active energy ray in two stages, first irradiate the active light beam by the above-mentioned method within 0.001 to 2.0 seconds after ink landing, and further irradiate the active light beam. That is, after that, another light source that is not driven may be provided and irradiated to complete the curing. By dividing the irradiation of the active energy ray into two stages, it is possible to further suppress the shrinkage of the recording material that occurs during ink curing.

[Colorant]
As the color material used in the ink jet ink of the present invention, it is preferable to use a dye or a pigment.

(dye)
There is no restriction | limiting in particular as dye which can be used by this invention, Water-soluble dyes, such as an acid dye, a direct dye, and a reactive dye, a disperse dye, etc. are mentioned.

  Specific examples of dyes applicable to the ink jet ink of the present invention are listed below, but the present invention is not limited to these exemplified dyes.

[Water-soluble dye]
Examples of water-soluble dyes that can be used in the present invention include azo dyes, methine dyes, azomethine dyes, xanthene dyes, quinone dyes, phthalocyanine dyes, triphenylmethane dyes, and diphenylmethane dyes.

<C. I. Acid Yellow>
1, 3, 11, 17, 18, 19, 23, 25, 36, 38, 40, 42, 44, 49, 59, 61, 65, 67, 72, 73, 79, 99, 104, 110, 114, 116, 118, 121, 127, 129, 135, 137, 141, 143, 151, 155, 158, 159, 169, 176, 184, 193, 200, 204, 207, 215, 219, 220, 230, 232, 235, 241, 242, 246,
<C. I. Acid Orange>
3, 7, 8, 10, 19, 24, 51, 56, 67, 74, 80, 86, 87, 88, 89, 94, 95, 107, 108, 116, 122, 127, 140, 142, 144, 149, 152, 156, 162, 166, 168,
<C. I. Acid Red>
88, 97, 106, 111, 114, 118, 119, 127, 131, 138, 143, 145, 151, 183, 195, 198, 211, 215, 217, 225, 226, 249, 251, 254, 256, 257, 260, 261, 265, 266, 274, 276, 277, 289, 296, 299, 315, 318, 336, 337, 37, 359, 361, 362, 364, 366, 399, 407, 415,
<C. I. Acid Violet>
17, 19, 21, 42, 43, 47, 48, 49, 54, 66, 78, 90, 97, 102, 109, 126,
<C. I. Acid Blue>
1, 7, 9, 15, 23, 25, 40, 62, 72, 74, 80, 83, 90, 92, 103, 104, 112, 113, 114, 120, 127, 128, 129, 138, 140, 142, 156, 158, 171, 182, 185, 193, 199, 201, 203, 204, 205, 207, 209, 220, 221, 224, 225, 229, 230, 239, 249, 258, 260, 264, 278, 279, 280, 284, 290, 296, 298, 300, 317, 324, 333, 335, 338, 342, 350,
<C. I. Acid Green>
9, 12, 16, 19, 20, 25, 27, 28, 40, 43, 56, 73, 81, 84, 104, 108, 109,
<C. I. Acid Brown>
2, 4, 13, 14, 19, 28, 44, 123, 224, 226, 227, 248, 282, 283, 289, 294, 297, 298, 301, 355, 357, 413, <C. I. Acid Black>
1, 2, 3, 24, 26, 31, 50, 52, 58, 60, 63, 107, 109, 112, 119, 132, 140, 155, 172, 187, 188, 194, 207, 222,
<C. I. Direct yellow>
8, 9, 10, 11, 12, 22, 27, 28, 39, 44, 50, 58, 79, 86, 87, 98, 105, 106, 130, 132, 137, 142, 147, 153,
<C. I. Direct orange>
6, 26, 27, 34, 39, 40, 46, 102, 105, 107, 118,
<C. I. Direct Red>
2, 4, 9, 23, 24, 31, 54, 62, 69, 79, 80, 81, 83, 84, 89, 95, 212, 224, 225, 226, 227, 239, 242, 243, 254,
<C. I. Direct Violet>
9, 35, 51, 66, 94, 95,
<C. I. Direct Blue>
1, 15, 71, 76, 77, 78, 80, 86, 87, 90, 98, 106, 108, 160, 168, 189, 192, 193, 199, 200, 201, 202, 203, 218, 225, 229, 237, 244, 248, 251, 270, 273, 274, 290, 291,
<C. I. Direct Green>
26, 28, 59, 80, 85,
<C. I. Direct Brown>
44, 106, 115, 195, 209, 210, 222, 223,
<C. I. Direct Black>
17, 19, 22, 32, 51, 62, 108, 112, 113, 117, 118, 132, 146, 154, 159, 169,
<C. I. Basic Yellow>
1, 2, 11, 13, 15, 19, 21, 28, 29, 32, 36, 40, 41, 45, 51, 63, 67, 70, 73, 91,
<C. I. Basic Orange>
2, 21, 22,
<C. I. Basic Red>
1, 2, 12, 13, 14, 15, 18, 23, 24, 27, 29, 35, 36, 39, 46, 51, 52, 69, 70, 73, 82, 109,
<C. I. Basic Violet>
1, 3, 7, 10, 11, 15, 16, 21, 27, 39,
<C. I. Basic Blue>
1, 3, 7, 9, 21, 22, 26, 41, 45, 47, 52, 54, 65, 69, 75, 77, 92, 100, 105, 117, 124, 129, 147, 151,
<C. I. Basic Green>
1, 4,
<C. I. Basic Brown>
1,
<C. I. Reactive Yellow>
2, 3, 7, 15, 17, 18, 22, 23, 24, 25, 27, 37, 39, 42, 57, 69, 76, 81, 84, 85, 86, 87, 92, 95, 102, 105, 111, 125, 135, 136, 137, 142, 143, 145, 151, 160, 161, 165, 167, 168, 175, 176,
<C. I. Reactive Orange>
1, 4, 5, 7, 11, 12, 13, 15, 16, 20, 30, 35, 56, 64, 67, 69, 70, 72, 74, 82, 84, 86, 87, 91, 92, 93, 95, 107,
<C. I. Reactive Red>
2, 3, 5, 8, 11, 21, 22, 23, 24, 28, 29, 31, 33, 35, 43, 45, 49, 55, 56, 58, 65, 66, 78, 83, 84, 106, 111, 112, 113, 114, 116, 120, 123, 124, 128, 130, 136, 141, 147, 158, 159, 171, 174, 180, 183, 184, 187, 190, 193, 194, 195, 198, 218, 220, 222, 223, 228, 235,
<C. I. Reactive Violet>
1, 2, 4, 5, 6, 22, 23, 33, 36, 38,
<C. I. Reactive Blue>
2, 3, 4, 5, 7, 13, 14, 15, 19, 21, 25, 27, 28, 29, 38, 39, 41, 49, 50, 52, 63, 69, 71, 72, 77, 79, 89, 104, 109, 112, 113, 114, 116, 119, 120, 122, 137, 140, 143, 147, 160, 161, 162, 163, 168, 171, 176, 182, 184, 191, 194, 195, 198, 203, 204, 207, 209, 211, 214, 220, 221, 222, 231, 235, 236,
<C. I. Reactive Green>
8, 12, 15, 19, 21,
<C. I. Reactive Brown>
2, 7, 9, 10, 11, 17, 18, 19, 21, 23, 31, 37, 43, 46, <C. I. Reactive Black>
5, 8, 13, 14, 31, 34, 39,
<C. I. Food Black>
1, 2,
Etc.

  Furthermore, examples of the dye include a compound represented by the following general formula (8) or a compound represented by the general formula (9).

In the general formula (8), R ₁ represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom or a phenylcarbonyl group. R ₂ may be different and represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom. R ₃ represents a hydrogen atom or a substitutable substituent, and is preferably a hydrogen atom or an alkyl group. R ₄ represents a hydrogen atom or a substitutable substituent, preferably a hydrogen atom or an aryloxy group. R ₅ may be different and represents a hydrogen atom or a substitutable substituent, and is preferably a sulfonic acid group. n represents an integer of 1 to 4, and m represents an integer of 1 to 5.

In the general formula (9), X represents a phenyl group or a naphthyl group, may be substituted with a substitutable substituent, and is preferably substituted with a sulfonic acid group or a carboxyl group. Y represents hydrogen ion, sodium ion, potassium ion, lithium ion, ammonium ion or alkylammonium ion. R ₆ may be different and represents a hydrogen atom or a substituent that can be substituted on the naphthalene ring. q represents 1 or 2. p represents an integer of 1 to 4. However, q + p = 5. Z represents a substitutable substituent, and represents a carbonyl group, a sulfonyl group or a group represented by the following general formula (10), and particularly preferably a group represented by the following general formula (10).

In the general formula (10), W ₁ and W ₂ each independently represent a halogen atom, amino group, hydroxyl group, alkylamino group or arylamino group, preferably a halogen atom, hydroxyl group or alkylamino group.

[Disperse dye]
As the disperse dye, various disperse dyes such as azo disperse dyes, quinone disperse dyes, anthraquinone disperse dyes, quinophthalone disperse dyes can be used, and specific compounds thereof are listed below.

<C. I. Disperse Yellow>
3, 4, 5, 7, 9, 13, 23, 24, 30, 33, 34, 42, 44, 49, 50, 51, 54, 56, 58, 60, 63, 64, 66, 68, 71, 74, 76, 79, 82, 83, 85, 86, 88, 90, 91, 93, 98, 99, 100, 104, 108, 114, 116, 118, 119, 122, 124, 126, 135, 140, 141, 149, 160, 162, 163, 164, 165, 179, 180, 182, 183, 184, 186, 192, 198, 199, 202, 204, 210, 211, 215, 216, 218, 224, 227, 231, 232,
<C. I. Disperse Orange>
1, 3, 5, 7, 11, 13, 17, 20, 21, 25, 29, 30, 31, 32, 33, 37, 38, 42, 43, 44, 45, 47, 48, 49, 50, 53, 54, 55, 56, 57, 58, 59, 61, 66, 71, 73, 76, 78, 80, 89, 90, 91, 93, 96, 97, 119, 127, 130, 139, 142,
<C. I. Disperse Red>
1, 4, 5, 7, 11, 12, 13, 15, 17, 27, 43, 44, 50, 52, 53, 54, 55, 56, 58, 59, 60, 65, 72, 73, 74, 75, 76, 78, 81, 82, 86, 88, 90, 91, 92, 93, 96, 103, 105, 106, 107, 108, 110, 111, 113, 117, 118, 121, 122, 126, 127, 128, 131, 132, 134, 135, 137, 143, 145, 146, 151, 152, 153, 154, 157, 159, 164, 167, 169, 177, 179, 181, 183, 184, 185, 188, 189, 190, 191, 192, 200, 201, 202, 203, 205, 206, 207, 210, 221, 224, 225, 227, 229, 23 , 240,257,258,277,278,279,281,288,298,302,303,310,311,312,320,324,328,
<C. I. Disperse Violet>
1, 4, 8, 23, 26, 27, 28, 31, 33, 35, 36, 38, 40, 43, 46, 48, 50, 51, 52, 56, 57, 59, 61, 63, 69, 77,
<C. I. Disperse Green>
9,
<C. I. Disperse Brown>
1, 2, 4, 9, 13, 19,
<C. I. Disperse Blue>
3, 7, 9, 14, 16, 19, 20, 26, 27, 35, 43, 44, 54, 55, 56, 58, 60, 62, 64, 71, 72, 73, 75, 79, 81, 82, 83, 87, 91, 93, 94, 95, 96, 102, 106, 108, 112, 113, 115, 118, 120, 122, 125, 128, 130, 139, 141, 142, 143, 146, 148, 149, 153, 154, 158, 165, 167, 171, 173, 174, 176, 181, 183, 185, 186, 187, 189, 197, 198, 200, 201, 205, 207, 211, 214, 224, 225, 257, 259, 267, 268, 270, 284, 285, 287, 288, 291, 293, 295, 297, 301, 315, 3 0,333,
<C. I. Disperse Black>
1, 3, 10, 24
Etc.

<Pigment>
As the pigment that can be used in the ink according to the present invention, conventionally known organic and inorganic pigments can be used, and are anionic pigments. For example, azo pigments such as azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, phthalocyanine pigments, perylene and perylene pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc. Examples include cyclic pigments, dye lakes such as acid dye lakes, organic pigments such as nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments, and inorganic pigments such as carbon black.

  Specific organic pigments are exemplified below.

  Examples of pigments for magenta or red include C.I. I. Pigment red 2, C.I. I. Pigment red 3, C.I. I. Pigment red 5, C.I. I. Pigment red 6, C.I. I. Pigment red 7, C.I. I. Pigment red 15, C.I. I. Pigment red 16, C.I. I. Pigment red 48: 1, C.I. I. Pigment red 53: 1, C.I. I. Pigment red 57: 1, C.I. I. Pigment red 122, C.I. I. Pigment red 123, C.I. I. Pigment red 139, C.I. I. Pigment red 144, C.I. I. Pigment red 149, C.I. I. Pigment red 166, C.I. I. Pigment red 177, C.I. I. Pigment red 178, C.I. I. And CI Pigment Red 222.

  Examples of the orange or yellow pigment include C.I. I. Pigment orange 31, C.I. I. Pigment orange 43, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 14, C.I. I. Pigment yellow 15, C.I. I. Pigment yellow 17, C.I. I. Pigment yellow 74, C.I. I. Pigment yellow 93, C.I. I. Pigment yellow 94, C.I. I. Pigment yellow 128, C.I. I. And CI Pigment Yellow 138.

  Examples of pigments for green or cyan include C.I. I. Pigment blue 15, C.I. I. Pigment blue 15: 2, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 16, C.I. I. Pigment blue 60, C.I. I. And CI Pigment Green 7.

  As a method for dispersing the pigment, for example, various dispersing machines such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used. It is also preferable to use a centrifugal separator or a filter for the purpose of removing the coarse particles of the pigment dispersion.

  In the ink according to the present invention, a self-dispersed pigment in which polar groups such as sulfonic acid and carboxylic acid are pendant on the pigment surface, or a pigment dispersed using a polymer dispersant is preferable.

  The polymer dispersant according to the present invention is not particularly limited, and a water-soluble resin or a water-insoluble resin is used. Examples of these polymers include styrene, styrene derivatives, vinyl naphthalene derivatives, acrylic acid, acrylic acid derivatives, methacrylic acid, methacrylic acid derivatives, maleic acid, maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid. Examples thereof include a polymer composed of a single monomer selected from acid derivatives, a copolymer composed of two or more monomers, and salts thereof. Water-soluble polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, cellulose derivatives, gelatin, and polyethylene glycol can also be used.

  The content of these water-soluble resins with respect to the total amount of ink is preferably 0.1 to 10% by mass, and more preferably 0.3 to 5% by mass. These water-soluble resins can be used in combination of two or more.

  The average particle size of the pigment dispersion used in the inkjet ink according to the present invention is preferably 500 nm or less, more preferably 200 nm or less, preferably 10 nm or more and 200 nm or less, and more preferably 10 nm or more and 150 nm or less. If the average particle size of the pigment dispersion exceeds 500 nm, the dispersion becomes unstable. In addition, even when the average particle size of the pigment dispersion is less than 10 nm, the stability of the pigment dispersion tends to deteriorate, and the storage stability of the ink tends to deteriorate.

  The particle size of the pigment dispersion can be determined by a commercially available particle size measuring device using a light scattering method, an electrophoresis method, a laser Doppler method or the like. It is also possible to obtain a particle image with a transmission electron microscope on at least 100 particles and perform statistical processing on the image using image analysis software such as Image-Pro (manufactured by Media Cybernetics). Is possible.

  Various methods such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, and a paint shaker can be used as a pigment dispersion method.

<Water-soluble solvent>
As the solvent relating to the ink of the present invention, an aqueous liquid medium is preferably used, and as the aqueous liquid medium, a mixed solvent such as water and a water-soluble organic solvent is more preferably used. Examples of water-soluble organic solvents that are preferably used include alcohols (eg, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol), polyhydric alcohols (eg, ethylene glycol, diethylene glycol, Triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol), polyhydric alcohol ethers (eg, ethylene glycol monomethyl ether, ethylene Glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol Nomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, ethylene glycol Monophenyl ether, propylene glycol monophenyl ether), amines (for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetra) , Tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.), heterocycles (eg, 2 -Pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone), sulfoxides (for example, dimethyl sulfoxide) and the like.

<Surfactant>
Surfactants preferably used in the ink according to the present invention include alkyl sulfates, alkyl ester sulfates, dialkyl sulfosuccinates, alkyl naphthalene sulfonates, alkyl phosphates, polyoxyalkylene alkyl ether phosphates, Anionic surfactants such as fatty acid salts, nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, acetylene glycols, polyoxyethylene-polyoxypropylene block copolymers, glycerin esters, Activators such as sorbitan esters, polyoxyethylene fatty acid amides, amine oxides, and cationic surfactants such as alkylamine salts and quaternary ammonium salts.

  These surfactants can also be used as pigment dispersants, and in particular, anionic and nonionic surfactants can be preferably used.

<Various additives>
The ink according to the present invention can contain other conventionally known additives. For example, optical brighteners, antifoaming agents, lubricants, preservatives, thickeners, antistatic agents, matting agents, water-soluble polyvalent metal salts, acid bases, pH adjusting agents such as buffer solutions, antioxidants, conductivity They are regulators, surface tension modifiers, rust inhibitors, inorganic pigments, and the like.

<Recording sheet>
The paper, coated paper, there is a non-coated paper, as the coated paper, the coating amount per 1m ² is one side 20g before and after of art paper, 1m ² per coated amount on one side 10g before and after the coated paper Examples include a light-weight coated paper having a coating amount per 1 m ^{2 of} about 5 g on one side, a finely coated paper, a mat-like finished mat-coated paper, a dull-like finished dull-coated paper, and a newsprint. Non-coated paper includes printing paper A using 100% chemical pulp, printing paper B using 70% or more chemical pulp, printing paper C using 40% or more and less than 70% chemical pulp, and printing using less than 40% chemical pulp. Examples thereof include paper D, gravure paper containing mechanical pulp and subjected to calendar treatment. Further details are described in detail in the “Latest Paper Processing Handbook” edited by the Paper Processing Handbook Editorial Committee, published by Tech Times, “Printing Engineering Handbook” edited by the Japan Printing Society.

  The plain paper is 80 to 200 μm uncoated paper belonging to a part of uncoated paper, special printing paper and information paper. The plain paper used in the present invention includes, for example, high-grade printing paper, intermediate-grade printing paper, low-grade printing paper, thin-like printing paper, fine-coating printing paper, special printing paper such as fine-quality printing paper, foam paper, PPC paper, and others There are information sheets and the like. Specifically, there are the following sheets and various modified / processed sheets using these sheets, but the present invention is not particularly limited thereto. High quality paper and colored high quality paper, recycled paper, copy paper / colored paper, OCR paper, carbonless paper / colored paper, synthetic paper such as YUPO 60, 80, 110 microns, YUPO COAT 70, 90 microns, etc. Coated paper 90kg, Foam mat paper 70, 90, 110kg, Foamed PET 38 microns, Mitsuori-kun (above, Kobayashi recording paper), OK fine paper, New OK fine paper, Sunflower, Phoenix, OK Royal White, Export fine paper ( NPP, NCP, NWP, Royal White) OK Book Paper, OK Cream Book Paper, Cream Premium Paper, OK Map Paper, OK Ishikari, Cucumber, OK Foam, OKH, NIP-N (above, Shin Oji Paper), Gold Wang, Toko, export quality paper, special demand quality paper, book paper, book paper L, light cream book paper, elementary textbook Paper, continuous slip paper, high quality NIP paper, silver ring, gold yang, gold yang (W), bridge, capital, silver ring book, harp, harp cream, SK color, securities paper, opera cream, opera, KYP medical record, silvia HN, Excellent Foam, NPI Foam DX (Nippon Paper), Pearl, Kinryo, Uscream fine paper, Special Book Paper, Super Book Paper, Book Paper, Diamond Foam, Inkjet Foam (Mitsubishi Paper), Carpet V, carpet SW, white elephant, luxury publication paper, cream carpet, cream white elephant, securities / voucher paper, book paper, map paper, copy paper, HNF (above, Hokuetsu), phone book cover, Book paper, cream shirairai, cream shirairaifu, cream shirairaifu, DSK (above, Daishowa Paper), Sendai MP fine paper, Jiang, Thunderbird quality, hanging paper, colored paper base, dictionary paper, cream book, white book, cream quality paper, map paper, continuous slip paper (above, Chuetsu Pulp), OP gold cherry (Chuetsu), gold sand, reference book paper, Replacement certificate paper (white), form printing paper, KRF, white foam, color foam, (K) NIP, fine PPC, Kishu inkjet paper (above, made by Kishu Paper), Taiou, Bright Foam, Kant, Kant White, Dante , CM paper, Dante comic, Heine, paperback book paper, Heine S, New AD paper, Utrilo Excel, Excel Super A, Kant Excel, Excel Super B, Dante Excel, Heine Excel, Excel Super C, Excel Super D, AD Excel, Excel Super E, New Bright Foam, New Bright NI P (above, made by Daio Paper), Sun Ring, Moon Ring, Cloud Pass, Galaxy, Baiyun, Wyeth, Moon Ring Ace, Baiyun Ace, Cloud Pass Ace (above, Nippon Paper Industries), Taiou, Bright Foam, Bright Nip (Nagoya Pulp), Peony A, Golden Pigeon, Special Peony, White Peony A, White Peony C, Silver Pigeon, Super White Peony A, Light Cream White Peony, Special Medium Quality Paper, White Pigeon, Super Medium Quality Paper, Blue Pigeon, Red Pigeon, Gold Pigeon M Snow Vision, Snow Vision, Gold Pigeon Snow Vision, White Pigeon M, Super DX, Hamanasu O, Red Pigeon M, HK Super Printing Paper (Made by Honshu Paper), Stalinden (A・ AW), Star Elm, Star Maple, Star Laurel, Star Poplar, MOP, Star Cherry I, Cherry I Super, Cherry II Super, Star Cherry III, Star Cherry IV, Cherry III Super, Cheri -IV Super (above, made by Maruzumi Paper), SHF (above, made by Toyo Pulp), TRP (above, made by Tokai Pulp), etc.

<Various films>
As the various films, all commonly used films can be used. For example, there are a polyester film, a polyolefin film, a polyvinyl chloride film, a polyvinylidene chloride film, and the like. Resin-coated paper that is photographic printing paper or YUPO paper that is synthetic paper can also be used.

<Various inkjet recording media>
As the various ink jet recording media, an ink receiving layer is formed on the surface using an absorbent support or a non-absorbent support as a base material. Examples of the ink receiving layer include a coating layer, a swelling layer, and a fine void layer.

  The swelling layer absorbs ink when the ink receiving layer made of a water-soluble polymer swells. The fine void layer is composed of inorganic or organic fine particles having a secondary particle size of about 20 to 200 nm and a binder, and fine voids of about 100 nm absorb ink.

  In recent years, an inkjet recording medium in which the above-mentioned fine void layer is provided on a base material using RC paper in which both sides of a paper base material are coated with an olefin resin is preferably used in terms of photographic images.

  As described above in detail, in the inkjet image recording apparatus using the ink that is crosslinked and cured by irradiation with actinic rays according to the present invention, as a cleaning method for the nozzle surface of the inkjet head, particularly in the vicinity of the nozzle, Irradiation with actinic rays during cleaning is effective in cleaning the vicinity of the nozzles of the inkjet head by combining with various cleaning means in combination with the characteristics of crosslinking and gelation by the actinic rays of the inkjet ink. Therefore, it is possible to obtain an ink jet image forming apparatus that is free from ink landing deviation and lack of ink over a long period of time. In addition, the ink jet image recording apparatus can be applied to various recording media, has high ink fixability and high adhesion to a substrate, and provides high quality prints or images in which feathering and bleeding are prevented.

1 is a diagram illustrating a schematic configuration of an entire inkjet recording apparatus according to the present invention. A state in which the blade wipes the nozzle surface of the inkjet head is shown. A mode that a blade wipes a nozzle surface while irradiating actinic rays is shown. A mode that a nozzle surface is cleaned with a cleaning roll is shown. A mode that a nozzle surface is cleaned while irradiating actinic light with a cleaning roll is shown. The state of cleaning the nozzle surface using a sheet-like cleaning member (cleaning cloth) is shown. A state in which the nozzle surface is cleaned using a cleaning cloth while being irradiated with actinic rays is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image recording part 2 Inkjet head 3 Irradiation means 4 Carriage 5 Guide member (linear guide)
6 Roller 7 Platen 8 Maintenance Unit 9 Home Position 81 Suction Cap 82 Blade 83 Irradiation Window 91 Cap P Recording Medium

Claims (5)

At least energy generating means for ink ejection using an actinic ray crosslinkable ink, an ink jet head having a nozzle for ejecting ink, an electric circuit for supplying a drive signal for the ink jet head, and a wiping operation in the vicinity of the nozzle of the ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for performing the ink discharge failure recovery means, the ink discharge failure recovery means includes a light source for irradiating actinic rays in the vicinity of the nozzle, and discharges ink from the nozzle of the ink jet head. The inkjet image forming apparatus according to claim 1, wherein the wiping operation in the vicinity of the nozzle is performed after irradiating an actinic ray from the light source in the vicinity of the nozzle. At least energy generating means for ink ejection using an actinic ray crosslinkable ink, an ink jet head having a nozzle for ejecting ink, an electric circuit for supplying a drive signal for the ink jet head, and a wiping operation in the vicinity of the nozzle of the ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for performing the ink discharge failure recovery means, the ink discharge failure recovery means includes a light source for irradiating actinic rays in the vicinity of the nozzle, and discharges ink from the nozzle of the ink jet head. In the inkjet image forming apparatus, the wiping operation in the vicinity of the nozzle is performed simultaneously with the irradiation of the actinic ray from the light source in the vicinity of the nozzle. At least using actinic ray crosslinkable ink, energy generating means for ink discharge, ink jet head having nozzle for discharging ink, electric circuit for supplying ink jet head drive signal, and ink transfer in the vicinity of nozzle of ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for transferring and removing the residual ink from the vicinity of the nozzle by pushing the member and then performing the peeling operation, the ink discharge failure recovery means is activated near the nozzle. Transferring and removing residual ink from the vicinity of the nozzle by the ink ejection failure recovery means, which is performed after the ink is ejected from the nozzle of the inkjet head, is provided in the vicinity of the nozzle. After irradiating actinic rays from the light source Inkjet image forming apparatus characterized by dividing. At least using actinic ray crosslinkable ink, energy generating means for ink discharge, ink jet head having nozzle for discharging ink, electric circuit for supplying ink jet head drive signal, and ink transfer in the vicinity of nozzle of ink jet head In the ink jet image forming apparatus provided with the ink discharge failure recovery means for transferring and removing the residual ink from the vicinity of the nozzle by pushing the member and then performing the peeling operation, the ink discharge failure recovery means is activated near the nozzle. The ink transfer member is provided with a light source for irradiating a light beam, and the ink transfer member removes residual ink from the vicinity of the nozzle by the ink discharge failure recovery means, which is performed after the ink is discharged from the nozzle of the inkjet head. Front from the light source provided on the back side Inkjet image forming apparatus which comprises carrying out later irradiated with active light rays in the vicinity of the nozzle. 5. The inkjet image forming apparatus according to claim 1, wherein the actinic ray crosslinkable ink has at least a coloring material, water, and a plurality of side chains in a hydrophilic main chain, and an active energy. An ink-jet image forming apparatus comprising an ink containing a polymer compound capable of crosslinking between side chains by irradiation of a line.

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