JP2010069797A - Recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording apparatus by which bleeding caused by the formation of a line image is suppressed. <P>SOLUTION: The recording apparatus 101 has an intermediate transfer belt 10, a solution supplying device 12 which supplies a curable solution 12A including at least both a curable material cured by a stimulus from the outside and a charged liquid absorbing component 12J for absorbing an ink liquid to the intermediate transfer belt 10 and forms a curing target layer 12B, an electric field applying device 30 which gives to the curing target layer 12B an electric field for moving the liquid absorbing component 12J in the curing target layer 12B toward a surface 12G which receives the ink, an inkjet recording head 14 which gives ink droplets 14A to the surface 12G which receives the ink of the curing target layer 12B with the electric field given thereto, a transfer device 16 which brings the curing target layer 12B with the ink droplets 14A given thereto into contact with a recording medium P and transfers the curing target layer 12B from the intermediate transfer belt 10 to the recording medium P, and an ultraviolet irradiation device 28 which supplies the stimulus that cures the curing target layer 12B to the curing target layer 12B. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a recording apparatus.

  As a recording method using ink, in order to perform recording on various recording media such as a penetrating medium and a non-penetrating medium, a method of recording on an intermediate transfer member and then transferring to a recording medium has been proposed.

  For example, Patent Document 1 discloses that before a flying ink droplet is transferred to an intermediate transfer member, a liquid is attached to the surface of the intermediate transfer member, and after ink is attached to the liquid, A recording method is disclosed in which ink is transferred to a printing medium together with a liquid.

  On the other hand, in Patent Document 2, in a transfer type ink jet printer system using oil-based ink, colored charged particles in an ink image formed on a transfer medium are temporarily fixed to the transfer medium by an electric field, and the solvent in the ink image is removed. After that, a technique for performing transfer is disclosed.

Japanese Patent Application Laid-Open No. 2001-212956 JP-A-6-171076

  An object of the present invention is to provide a recording apparatus in which bleeding due to line image formation is suppressed.

The above problem is solved by the following means. That is,
The invention according to claim 1
An intermediate transfer member;
A curable solution that forms a curable solution layer by supplying a curable solution containing at least a curable material that is cured by an external stimulus and a charged liquid-absorbing component that absorbs ink onto the intermediate transfer member. Layer forming means;
An electric field applying means for applying to the curable solution layer an electric field for moving the liquid-absorbing component in the curable solution layer toward a surface of the curable solution layer that receives ink;
Ink application means for applying ink droplets to the ink receiving surface of the curable solution layer to which the electric field has been applied and the curable solution layer to which the ink droplets have been applied are brought into contact with a recording medium, and the intermediate transfer Transfer means for transferring the curable solution layer from a body to the recording medium;
And a stimulus supply unit that supplies the stimulus for curing the curable solution layer to the curable solution layer.

The invention according to claim 2
The recording apparatus according to claim 1, further comprising a heating unit that heats the curable solution layer before the electric field is applied and at least one of the electric field being applied.

According to the first aspect of the present invention, it is possible to suppress bleeding due to line image formation as compared with the case where the configuration of the present invention is not provided.
According to the second aspect of the present invention, it is possible to further suppress bleeding due to line image formation as compared with the case where the configuration of the present invention is not provided.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, the same code | symbol is provided to the member which has the substantially same function throughout all the drawings, and the overlapping description may be abbreviate | omitted.

<First Embodiment>
FIG. 1 is a configuration diagram illustrating a recording apparatus according to the first embodiment. 2 is a 2-2 end view of the recording apparatus shown in FIG. 1, and FIG. 3 is a 3-3 end view of the recording apparatus shown in FIG.

  As shown in FIG. 1, the recording apparatus 101 according to the first embodiment is, for example, around the endless belt-like intermediate transfer belt 10 (intermediate transfer body), upstream in the moving direction (arrow direction) of the intermediate transfer belt 10. In order from the side, a solution supply device 12 (curable solution layer forming means) for supplying a curable solution 12A (details will be described later) onto the intermediate transfer belt 10 to form a cured layer 12B (curable solution layer), an intermediate transfer belt An ink jet recording head 14 (ink applying means) that forms an image T by applying ink droplets 14A to a surface 12G that receives ink of the layer 12B to be cured formed on the substrate 10, and a layer 12B to be cured on which the image T is formed. A transfer device 16 (transfer means) for transferring the cured layer 12B on which the image T has been formed by contacting the recording medium P and applying pressure to the recording medium P, and the surface of the intermediate transfer belt 10 A cleaning device 20 for removing residues and adhered foreign substances (paper dust of the recording medium P) or the like of the curable layer 12B is arranged to remaining.

  Around the intermediate transfer belt 10, between the solution supply device 12 and the inkjet recording head 14, the electrode 30A and the electrode 30B of the electric field applying device 30 are provided on the cured layer 12B formed on the surface of the intermediate transfer belt 10. The intermediate transfer belt 10 and the cured layer 12B are disposed so as to be sandwiched therebetween. Specifically, the plate-like electrode 30 </ b> A is arranged outside the intermediate transfer belt 10, and the plate-like electrode 30 </ b> B having the same area as the electrode 30 </ b> A is arranged inside the intermediate transfer belt 10.

  Further, on the upstream side of the electric field applying device 30 in the rotation direction of the intermediate transfer belt 10, a heating source 32 (heating means) for heating the cured layer 12 </ b> B on the intermediate transfer belt 10 is disposed outside the intermediate transfer belt 10. Has been.

Further, inside the intermediate transfer belt 10, there is provided an ultraviolet irradiation device 18 that supplies the cured layer 12 </ b> B with ultraviolet rays that cure the cured layer 12 </ b> B during contact between the cured layer 12 </ b> B and the recording medium P. That is, the ultraviolet irradiation device 18 is installed facing the region where the cured layer 12B is in contact with the recording medium P.
Further, on the downstream side in the traveling direction of the recording medium P with respect to the ultraviolet irradiation device 18, the ultraviolet irradiation for fixing the cured layer 12B to the recording medium P by further curing the cured layer 12B transferred to the recording medium P. A device 28 (stimulus supply means) is arranged.

  The intermediate transfer belt 10 is supported and disposed so as to rotate while applying tension from the inner peripheral surface side by, for example, three support rolls 10A to 10C and a pressure roll 16B (transfer device 16). Further, the intermediate transfer belt 10 has a width (length in the axial direction) equal to or greater than the width of the recording medium P.

  The material of the intermediate transfer belt 10 is a known material generally used as an intermediate transfer belt, for example, various resins (for example, polyimide, polyamideimide, polyester, polyurethane, polyamide, polyethersulfone, fluorine resin, etc. ), Various rubbers (for example, nitrile rubber, ethylene propylene rubber, chloroprene rubber, isoprene rubber, styrene rubber, butadiene rubber, butyl rubber, chlorosulfonated polyethylene, urethane rubber, epichlorohydrin rubber, acrylic rubber, silicone rubber, fluorine rubber) Etc.) and metal materials such as stainless steel.

In the present embodiment, since the ultraviolet irradiation device 18 is provided inside the intermediate transfer belt 10, it is desirable that the intermediate transfer belt 10 has high ultraviolet transmittance and high ultraviolet resistance. Specific examples of the material of the intermediate transfer belt 10 include ETFE (ethylene-tetrafluoroethylene copolymer), polyimide film, polyolefin film, and the like.
Further, the intermediate transfer belt 10 may have a single layer configuration or a layered configuration.

  The solution supply device 12 is formed of, for example, a supply roller 12D that supplies the curable solution 12A to the intermediate transfer belt 10 and a supplied curable solution 12A in a housing 12C that stores the curable solution 12A. And a blade 12E that defines the layer thickness of the cured layer 12B.

  The solution supply device 12 may be configured such that the supply roller 12 </ b> D continuously contacts the intermediate transfer belt 10 or is separated from the intermediate transfer belt 10. Further, the solution supply device 12 may supply the curable solution 12A to the housing 12C from an independent solution supply system (not shown) so that the supply of the curable solution 12A is not interrupted. Details of the curable solution 12A and the liquid-absorbing component 12J contained in the curable solution 12A will be described later.

  The solution supply device 12 is not limited to the above-described configuration, and a known supply method (coating method: for example, die coater, bar coater coating, spray coating, inkjet coating, air knife coating, blade coating, roll A device using a method of application) is applied.

  As shown in FIG. 2, the heat source 32 is disposed at a position facing the surface 12G for receiving ink of the curable layer 12B so as not to contact the surface 12G for receiving ink, and the ink of the curable layer 12B. Heat is supplied to the surface 12G that receives the heat. Examples of the heat source 32 include a halogen lamp and a Colts lamp. Further, a heating roll incorporating a heating mechanism is used as the heating source 32, and the heating roll is disposed in contact with the surface of the intermediate transfer belt 10 that does not contact the cured layer 12 </ b> B, and heat is applied to the cured layer 12 </ b> B through the intermediate transfer belt 10. It is good also as a form which supplies. The heating method of the heating source 32 is not particularly limited, and examples thereof include a heater heating method, an oven method, an electromagnetic induction heating method, and a heating method using infrared irradiation.

  The electric field applying device 30 includes an electrode 30A and an electrode 30B, and is arranged in such a manner that the intermediate transfer belt 10 and the cured layer 12B are sandwiched between the electrode 30A and the electrode 30B.

  The inkjet recording head 14 includes, for example, a recording head 14K for applying black ink, a recording head 14C for applying cyan ink, and a magenta ink from the upstream side in the moving direction of the intermediate transfer belt 10. The recording head 14 </ b> M and the recording head 14 </ b> Y for applying the yellow ink are configured to include recording heads of respective colors. Of course, the configuration of the recording head 14 is not limited to the above-described configuration. For example, the recording head 14 may be configured by only the recording head 14K, or may be configured by only the recording head 14C, the recording head 14M, and the recording head 14Y.

  Each recording head 14 has a distance between the surface of the intermediate transfer belt 10 and the nozzle surface of the recording head 14 on the non-bending region of the intermediate transfer belt 10 that is rotated and supported by tension, for example, 0.7 to 1. 5 mm is arranged.

Each recording head 14 is preferably a line type ink jet recording head having a width equal to or greater than the width of the recording medium P, but a conventional scanning ink jet recording head may be used.
The ink application method of each recording head 14 is not limited as long as ink is applied, such as a piezoelectric element driving type and a heating element driving type. Details of the ink will be described later.

  The transfer device 16 is configured as follows. Specifically, for example, the intermediate transfer belt 10 is stretched by the pressure roll 16B and the support roll 10C to form a non-bending region. In the non-bending region of the intermediate transfer belt 10, a support 22 for supporting the recording medium P is provided at a position facing the pressure roll 16B and the support roll 10C. The pressure roll 16 </ b> A is disposed at a position facing the pressure roll 16 </ b> B of the intermediate transfer belt 10 and contacts the recording medium P through an opening (not shown) provided in the support 22.

  That is, a position where the intermediate transfer belt 10 and the recording medium P are sandwiched by the support roll 10C and the support 22 from a position where the intermediate transfer belt 10 and the recording medium P are sandwiched by the pressure rolls 16A and 16B (hereinafter sometimes referred to as “contact start position”). In the transfer region up to (hereinafter sometimes referred to as “peeling position”), the cured layer 12B is in contact with both the intermediate transfer belt 10 and the recording medium P.

  The ultraviolet irradiation device 18 is provided inside the intermediate transfer belt 10 and irradiates the cured layer 12B in contact with both the intermediate transfer belt 10 and the recording medium P via the intermediate transfer belt 10 in the transfer region. To do.

  The ultraviolet irradiation device 28 is provided outside the intermediate transfer belt 10 at a position facing the surface of the recording medium P on which the cured layer 12B is formed, and directly on the cured layer 12B peeled off from the intermediate transfer belt 10. Irradiate ultraviolet rays.

  Examples of the ultraviolet irradiation device 18 and the ultraviolet irradiation device 28 include a metal halide lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a deep ultraviolet lamp, a lamp that uses a microwave to excite a mercury lamp from the outside without an electrode, an ultraviolet laser, a xenon lamp, and a UV. -LED etc. are applied.

  As the recording medium P, a permeation medium (for example, plain paper, coated paper, etc.) and a non-penetration medium (for example, art paper, resin film, etc.) are applied. The recording medium P is not limited to these, and includes other industrial products such as semiconductor substrates.

  Hereinafter, an image recording process of the recording apparatus 101 according to the present embodiment will be described.

  In the recording apparatus 101 according to the present embodiment, the intermediate transfer belt 10 is rotationally driven. First, the solution supply device 12 supplies the curable solution 12A containing the liquid absorbing component 12J charged to the intermediate transfer belt 10, A cured layer 12B including the charged liquid absorbing component 12J is formed. In the cured layer 12B before applying the electric field by the electric field applying device 30, as shown in FIG. 2, the distribution of the liquid absorbing component 12J in the cured layer 12B is considered to have a small bias.

  Here, the layer thickness (average film thickness) of the curable layer 12B is not particularly limited, but is preferably 1 μm or more and 50 μm or less and more preferably 3 μm or more and 20 μm or less from the viewpoint of achieving both image formability and transferability. .

  Next, heat is supplied from the heating source 32 to the cured layer 12 </ b> B formed on the surface of the intermediate transfer belt 10. It is estimated that the curable layer 12B supplied with heat rises in temperature and decreases in viscosity, so that the liquid absorbing component 12J in the curable layer 12B can easily move.

  Further, an electric field is applied to the curable layer 12B by the electric field applying device 30, and the liquid component 12J that has been charged in advance moves to the surface 12G that receives ink by this electric field. At this time, the direction and intensity of the electric field applied to the curable layer 12B by the electric field applying device 30 are not particularly limited as long as the liquid absorbing component 12J moves to the surface 12G that receives ink, and the strength is not particularly limited. The appropriate direction and strength vary depending on the amount of charge and the viscosity of the cured layer 12B. For example, when polyacrylic acid resin particles are used as the liquid absorption component 12J, since the liquid absorption component 12J is negatively charged, the potential difference of the electrode 30A with respect to the electrode 30B is the width of the electrode 30A or the electrode 30B ( A range of +1 kV / m or more and 10 kV / m or less per 1 m (width in a direction perpendicular to the traveling direction of the intermediate transfer belt 10) is preferable.

  Next, the ink droplet 14A is ejected by the ink jet recording head 14, and the ink droplet 14A is applied to the surface 12G of the curable layer 12B that receives the ink. The ink jet recording head 14 applies ink droplets 14A to predetermined positions of the cured layer 12B based on predetermined image information.

  At this time, the application of the ink droplets 14A by the ink jet recording head 14 is performed on a non-bent region in the intermediate transfer belt 10 which is rotated and supported by tension. That is, the ink droplets 14 </ b> A are applied to the cured layer 12 </ b> B in a state where the belt surface is not bent. The ink droplets 14A ejected by the ink jet recording head 14 are absorbed by the liquid absorbing component 12J of the cured layer 12B.

  Next, the recording medium P and the intermediate transfer belt 10 are sandwiched between the pressure rolls 16A and 16B of the transfer device 16, and pressure is applied. At this time, the surface 12G that receives the ink of the curable layer 12B on the intermediate transfer belt 10 contacts the recording medium P at the contact start position, and then reaches the peeling position sandwiched between the support roll 10C and the support 22. The state where the cured layer 12B is in contact with both the intermediate transfer belt 10 and the recording medium P is maintained.

  Here, the pressure applied to the cured layer 12B by the pressure rolls 16A and 16B is 0.001 MPa or more and 2 MPa or less, preferably 0.001 MPa or more and 0.5 MPa or less, from the viewpoint of improving transfer efficiency and suppressing image disturbance. It is desirable to be in the range.

  Next, the ultraviolet ray irradiation device 18 irradiates the cured layer 12B in contact with both the intermediate transfer belt 10 and the recording medium P (during contact) with ultraviolet rays through the intermediate transfer belt 10, thereby The cured layer 12B is cured. Specifically, ultraviolet irradiation is started after the cured layer 12B on the intermediate transfer belt 10 comes into contact with the recording medium P (after passing through the contact start position), and the cured layer 12B is peeled off from the intermediate transfer belt 10. The ultraviolet irradiation is terminated before being performed (before reaching the peeling position).

The ultraviolet irradiation conditions in the ultraviolet irradiation device 18 are not particularly limited, and can be selected according to the type of the ultraviolet curable material, the thickness of the layer to be cured 12B, and the like. However, it is desirable that the ultraviolet irradiation amount by the ultraviolet irradiation device 18 is an amount that cures to such an extent that the cured layer 12B is easily peeled off from the intermediate transfer belt 10. Specifically, for example, when using a high pressure mercury lamp as an ultraviolet irradiation apparatus 18, the accumulated light quantity of ultraviolet irradiation by ultraviolet irradiation device 18 is preferably less than 10 mJ / cm ² or more ^{5000J / cm 2, 10mJ / cm} 2 or more Less than 1000 mJ / cm ² is more preferable.

  Next, the curable resin layer (image layer) including the image T by the ink droplet 14A is formed on the recording medium P by peeling the curable layer 12B from the intermediate transfer belt 10 at the peeling position. In the cured layer 12B peeled off from the intermediate transfer belt 10, the surface 12G that receives ink is in contact with the recording medium P, and the exposed portion 12L that is the surface opposite to the surface 12G that receives the ink of the cured layer 12B is exposed. State.

  Next, the cured layer 12B on the recording medium P peeled off from the intermediate transfer belt 10 is irradiated with ultraviolet rays or the like directly on the surface not in contact with the recording medium P by the ultraviolet irradiation device 28 and further cured. It is fixed on the recording medium P.

The ultraviolet irradiation conditions in the ultraviolet irradiation device 28 are not particularly limited, and can be selected according to the type of ultraviolet curable material, the thickness of the layer to be cured 12B, and the like. For example, when the high-pressure mercury lamp is used as the ultraviolet irradiation device 18 and the metal halide lamp is used as the ultraviolet irradiation device 28, the total integrated light quantity of the ultraviolet irradiation by the ultraviolet irradiation device 18 and the ultraviolet irradiation device 28 is improved in transfer efficiency and heat generation suppression. From the viewpoint, 20 mJ / cm ² or more and less than 10,000 J / cm ² is preferable, and 50 mJ / cm ² or more and less than 4000 mJ / cm ² is more preferable.

Then, the residue and foreign matter of the cured layer 12B remaining on the surface of the intermediate transfer belt 10 after the cured layer 12B is transferred to the recording medium P are removed by the cleaning device 20, and again on the intermediate transfer belt 10, The curable solution 12A is supplied by the solution supply device 12 to form the curable layer 12B, and the image recording process is repeated.
As described above, the recording apparatus 101 according to the present embodiment performs image recording.

  In the present embodiment, the ink droplet 14A is cured after the liquid absorbing component 12J in the cured layer 12B moves to the surface 12G for receiving ink due to the electric field applied to the cured layer 12B by the electric field applying device 30. It is applied to the surface 12G for receiving the ink of the layer 12B. Therefore, even if the ratio of the liquid absorbing component 12J in the curable solution 12A is low, the ratio of the liquid absorbing component 12J in the surface 12G that receives ink is increased by applying an electric field. When ink is applied in this state, it is presumed that the probability that the ink droplet 14A contacts the liquid absorbing component 12J is high, and the ink liquid absorbing property by the cured layer 12B is improved.

  Moreover, in this embodiment, since the to-be-cured layer 12B is heated by the heating source 32 before giving an electric field to the to-be-cured layer 12B, when the temperature of the to-be-cured layer 12B rises, the viscosity of the to-be-cured layer 12B Is going down. Therefore, since the electric field is applied to the cured layer 12B in a state where the liquid absorbing component 12J is easy to move, the liquid absorbing component 12J easily moves to the ink receiving surface 12G, and the liquid absorbing component 12J receives the ink. It is considered that the ink absorbing property by the cured layer 12B becomes better because the ink tends to gather on the surface 12G.

In addition, in this embodiment, although the to-be-cured layer 12B is heated by the heating source 32 before the electric field application to the to-be-cured layer 12B by the electric field application apparatus 30, it is high temperature compared with the temperature before a heating. As long as an electric field is applied to the cured layer 12B in this state, the present invention is not limited to this. Specifically, for example, an electric field may be applied while heating the curable layer 12B.
Further, in the case where the viscosity of the curable layer 12B is low and the liquid absorbing component 12J moves by an electric field without heating, the heating source 32 may not be included.
On the other hand, when the viscosity of the curable layer 12B before heating is high, the shape of the curable layer 12B is stable and the layer thickness of the curable layer 12B can be easily controlled. By heating the layer 12B, the advantage of improving the liquid absorption of the cured layer 12B accompanying the movement of the liquid absorption component 12J by an electric field can be obtained at the same time.

  In the present embodiment, as shown in FIG. 3, the width of the electrode 30A and the electrode 30B (the width in the direction perpendicular to the traveling direction of the intermediate transfer belt 10) is larger than the width of the cured layer 12B. An electric field is applied to the entire cured layer 12B. Generally, the electric field generated from the end of the electrode has a lower density than the electric field generated near the center of the electrode. Therefore, in order to apply a uniform electric field to the entire curable layer 12B and move the liquid absorbing component 12J in the entire curable layer 12B, the electrode 30A and the electrode from the curable layer 12B as in the present embodiment. It is desirable that 30B protrudes.

In the present embodiment, plate-like electrodes are used as the electrode 30A and the electrode 30B. However, the present invention is not limited to this, and for example, rod-like electrodes may be used.
In the present embodiment, the electric field is applied to the entire curable layer 12B. However, the present invention is not limited to this. For example, the image portion of the curable layer 12B (the ink droplet 14A is applied by the recording head 14). The electric field may be applied only to the portion). Specifically, for example, a mode in which an electric field is applied only to a corresponding portion of the curable layer 12B according to image data by the electric field applying device 30 provided with a control device that separately controls the divided electrodes, and the like. .

  In the present embodiment, only the liquid absorbing component 12J is charged and components other than the liquid absorbing component 12J in the cured layer 12B (such as a curable material) are not charged. Absent. Specifically, for example, in addition to the liquid absorption component 12J, other components that are charged with a polarity opposite to that of the liquid absorption component 12J are included, and the other components move in the opposite direction to the liquid absorption component 12J due to an electric field. The form etc. are mentioned.

In the present embodiment, it is desirable that the surface free energy (γ _T ) on the surface of the intermediate transfer belt 10 in contact with the cured layer 12B is low. In particular, the surface free energy (γ _T ) is preferably lower than the surface free energy (γ _P ) of the recording medium P on the surface in contact with the cured layer 12B, and more preferably a condition that satisfies the following equation.
Formula: γ _P −γ _T > 10

  The value of the surface free energy is calculated, for example, by using a contact angle meter CAM-200 (manufactured by KSV) and using a program calculation of the device built-in using the Zisman method.

In the present embodiment, in order to reduce the value of the surface free energy (γ _T ), the intermediate transfer belt 10 having a surface release layer on the surface in contact with the cured layer 12B may be used.
Examples of the material used for the surface release layer include fluorine-based resin materials. Specifically, for example, fluorine resin, fluorine-modified urethane and silicone resin, copolymerized fluorine rubber, fluorine resin-copolymerized vinyl ether, Powder paint or resin tube such as PFA (tetrafluoroethylene perfluoroalkoxy resin), FEP (tetrafluoroethylene / hexafluoropropylene copolymer paint), PTFE (tetrafluoroethylene) paint, PTFE-dispersed urethane paint, Furthermore, an ETFE (polytetrafluoroethylene) tube, PVdF (polyvinylidene fluoride), a PHV (polytetrafluorovinylidene) resin material, etc. are mentioned.

In the present embodiment, a release agent coating apparatus that supplies a release agent to the intermediate transfer belt 10 before forming the curable layer 12B and forms a release agent layer may be further provided.
By further providing a release agent coating device, it is easy to set the surface free energy (γ _T ) of the intermediate transfer belt 10 on the surface with which the cured layer 12B is in contact with the recording medium. The transfer efficiency of the cured layer 12B to P is improved.
Further, with the above-described configuration, the stability with time is improved and the cleaning property of the surface of the intermediate transfer belt 10 is improved while being hardly affected by the change in the surface state of the intermediate transfer belt 10 with time.
Here, the “surface free energy (γ _T )” in the embodiment having the release agent coating apparatus as in the above configuration is in contact with the cured layer 12B in the intermediate transfer belt 10 on which the release agent layer is formed. It means the surface free energy of the surface.

  As a release agent coating apparatus, a known coating method (for example, bar coater coating, spray coating, ink jet coating, air knife coating, blade coating, roll coating, etc.) is used. The device is applied. Specifically, for example, the thickness of the release agent layer formed by the supply roller that supplies the release agent to the intermediate transfer belt 10 and the supplied release agent in the housing that stores the release agent. Examples thereof include a blade that defines and a heating means that heats and melts the release agent.

  Specific examples of the release agent include silicone oil, fluorine oil, hydrocarbon / polyalkylene glycol, fatty acid ester, phenyl ether, phosphate ester, etc. Among these, silicone oil, fluorine oil Oil and polyalkylene glycol are preferred.

Examples of the silicone oil include straight silicone oil and modified silicone oil.
Examples of the straight silicone oil include dimethyl silicone oil and methyl hydrogen silicone oil.
Examples of the modified silicone oil include methylstyryl-modified oil, alkyl-modified oil, higher fatty acid ester-modified oil, fluorine-modified oil, and amino-modified oil.

  Examples of the polyalkylene glycol include polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide copolymer, and polybutylene glycol. Among these, polypropylene glycol and polyethylene glycol are preferable.

  In the present embodiment, ultraviolet rays are irradiated by the ultraviolet irradiation device 18 during contact between the cured layer 12B and the intermediate transfer belt 10 in the transfer process, and the cured layer 12B after passing through the peeling position is irradiated by the ultraviolet irradiation device 28. Although ultraviolet rays are irradiated, it is not limited to this form. Specifically, for example, a mode in which only one of the ultraviolet irradiation device 18 and the ultraviolet irradiation device 28 is used, a mode in which the ultraviolet irradiation measure 28 is irradiated through the recording medium, and a contact start position between the cured layer 12B and the intermediate transfer belt 10 are set. Examples include a mode in which ultraviolet irradiation is started before or when passing, a mode in which ultraviolet irradiation is started before passing through the contact start position, and a mode that ends before or after passing.

  In the present embodiment, the ultraviolet irradiation device (the ultraviolet irradiation device 18 and the ultraviolet irradiation device 28) is used as the stimulus supply device, but is not limited thereto. The kind of stimulus supply apparatus is selected according to the kind of curable material contained in the curable solution 12A to be applied. Specifically, for example, when an ultraviolet curable material that is cured by irradiation with ultraviolet rays is applied, the stimulation supply device is an ultraviolet irradiation device that irradiates the curable solution 12A (the cured layer 12B formed thereby) with ultraviolet rays. Apply. In addition, when an electron beam curable material that is cured by electron beam irradiation is applied, an electron beam irradiation device that irradiates an electron beam to the curable solution 12A (the cured layer 12B formed thereby) is applied as a stimulus supply device. To do. Moreover, when applying the thermosetting material which hardens | cures by provision of heat, the heat provision apparatus which provides heat to the curable solution 12A (cured layer 12B formed by this) is applied as a stimulus supply apparatus.

As the electron beam irradiation device, for example, there are a scanning type / curtain type, etc. The curtain type draws thermoelectrons generated in the filament by a grid in a vacuum chamber and further accelerates at once by a high voltage (for example, 70 to 300 kV). It is a device that emits an electron current, passes through the window foil, and emits it to the atmosphere side. The wavelength of an electron beam is generally smaller than 1 nm and has a large energy and ranges up to several MeV, but energy of several tens to several hundreds keV is applied when the wavelength of the electron beam is on the order of pm.
The electron beam irradiation conditions are not particularly limited and may be selected according to the type of electron beam curable material, the thickness of the layer to be cured 12B, and the like. For example, the electron dose is 5 to 100 kGy level or the like.

As the heat applying device, for example, a halogen lamp, a ceramic heater, a nichrome wire heater, a microwave heating, an infrared lamp, or the like is applied. An electromagnetic induction heating device is also used as the heat application device.
Here, the heat application condition is not particularly limited and may be selected according to the thermosetting material type, the thickness of the layer to be cured 12B, and the like. For example, in air, it is 5 min in a 200 ° C. environment. .

  In this embodiment, the intermediate transfer belt 10 is used as an intermediate transfer member, but the present invention is not limited to this. For example, an intermediate transfer drum or the like may be used as an intermediate transfer member.

  In the present embodiment, a full color image is recorded on the recording medium P by selectively applying ink droplets 14A from the inkjet recording heads 14 of black, yellow, magenta, and cyan based on the image data. However, the present invention is not limited to recording characters and images on a recording medium. That is, the apparatus according to the present invention can be applied to industrially used droplet application (jetting) apparatuses, a method for forming an image by transfer using a plate, an image forming method by screen printing, and the like.

<Curable solution>
Hereinafter, the details of the curable solution 12A will be described.
The curable solution 12A includes at least a curable material that is cured by an external stimulus (energy) and a charged liquid absorbing component 12J that absorbs ink, and may include other components as necessary. .

  Here, the “curable material curable by external stimulus (energy)” contained in the curable solution 12A means a material that is cured by an external stimulus and becomes a “curable resin”. Specific examples include curable monomers, curable macromers, curable oligomers, and curable prepolymers.

―Curable material―
Examples of the curable material include an ultraviolet curable material, an electron beam curable material, and a thermosetting material. UV curable materials are most desirable because they are easy to cure, have a faster cure speed and are easier to handle than others. The electron beam curable material does not require a polymerization initiator, and it is easy to control the coloration of the cured layer. Thermoset materials are cured without the need for extensive equipment. In addition, a curable material is not restricted to these, For example, the curable material hardened | cured with moisture, oxygen, etc. is applied.

  Examples of the “ultraviolet curable resin” obtained by curing the ultraviolet curable material include acrylic resin, methacrylic resin, urethane resin, polyester resin, maleimide resin, epoxy resin, oxetane resin, polyether resin, and polyvinyl ether resin. Etc. The curable solution 12A contains at least one of an ultraviolet curable monomer, an ultraviolet curable macromer, an ultraviolet curable oligomer, and an ultraviolet curable prepolymer. The curable solution 12A desirably contains an ultraviolet polymerization initiator for causing the ultraviolet curing reaction to proceed. Furthermore, the curable solution 12A may contain a reaction aid, a polymerization accelerator, and the like for further proceeding the polymerization reaction as necessary.

  Here, examples of the ultraviolet curable monomer include alcohol / polyhydric alcohol / amino alcohol acrylic ester, alcohol / polyhydric alcohol methacrylate, acrylic aliphatic amide, acrylic alicyclic amide, acrylic aromatic Radical curable materials such as aromatic amides; and cationic curable materials such as epoxy monomers, oxetane monomers, and vinyl ether monomers. Examples of the ultraviolet curable macromer, the ultraviolet curable oligomer, and the ultraviolet curable prepolymer include those obtained by polymerizing these monomers at a predetermined polymerization degree, epoxy, urethane, polyester, polyether skeleton, acryloyl group, Examples include radical curable materials such as epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, urethane methacrylate, and polyester methacrylate to which a methacryloyl group is added.

When the curing reaction is a type that proceeds by radical reaction, examples of the ultraviolet polymerization initiator include benzophenone, thioxanthone, benzyldimethyl ketal, α-hydroxyketone, α-hydroxyalkylphenone, α-aminoketone, α-aminoalkyl. Examples include phenone, monoacylphosphine oxide, bisacylphosphine oxide, hydroxybenzophenone, aminobenzophenone, titanocene type, oxime ester type, and oxyphenylacetate type.
When the curing reaction is a type that proceeds by a cationic reaction, examples of the ultraviolet polymerization initiator include arylsulfonium salts, aryldiazonium salts, diaryliodonium salts, triarylsulfonium salts, allene-ion complex derivatives, and triazine-based initiators. Etc.

  Examples of the “electron beam curable resin” obtained by curing the electron beam curable material include acrylic resin, methacrylic resin, urethane resin, polyester resin, polyether resin, and silicone resin. The curable solution 12A contains at least one of an electron beam curable monomer, an electron beam curable macromer, an electron beam curable oligomer, and an electron beam curable prepolymer.

  Here, examples of the electron beam curable monomer, the electron beam curable macromer, the electron beam curable oligomer, and the electron beam curable prepolymer include the same materials as the ultraviolet curable material.

  Examples of the “thermosetting resin” obtained by curing the thermosetting material include an epoxy resin, a polyester resin, a phenol resin, a melamine resin, a urea resin, and an alkyd resin. The curable solution 12A contains at least one of a thermosetting monomer, a thermosetting macromer, a thermosetting oligomer, and a thermosetting prepolymer. Further, a curing agent may be added during the polymerization. Further, the curable solution 12A may include a thermal polymerization initiator for causing the thermosetting reaction to proceed.

  Here, examples of the thermosetting monomer include polyalcohols such as phenol, formaldehyde, bisphenol A, epichlorohydrin, cyanuric amide, urea and glycerin, acids such as phthalic anhydride, maleic anhydride, and adipic acid. It is done. Examples of the thermosetting macromer, thermosetting oligomer, and thermosetting prepolymer include those obtained by polymerizing these monomers at a predetermined polymerization degree, epoxy prepolymers, and polyester prepolymers.

  Examples of the thermal polymerization initiator include acids such as protonic acid / Lewis acid, alkali catalysts, and metal catalysts.

As described above, the curable material may be anything as long as it is cured (for example, cured by the progress of the polymerization reaction) by external energy such as ultraviolet rays, electron beams, and heat.
Among the curable materials, a material having a high curing speed (for example, a material having a high polymerization reaction speed) is desirable in view of speeding up image recording. Examples of such a curable material include a radiation curable curable material (the above-described ultraviolet curable material, electron beam curable material, and the like).

  The curable material may be modified with Si, fluorine, or the like in consideration of wettability with the intermediate transfer member or the like. Moreover, it is desirable that the curable material contains a polyfunctional prepolymer in consideration of the curing speed and the degree of curing.

―Liquid absorption component―
The curable solution 12A includes a charged liquid-absorbing component 12J that absorbs ink as a material for fixing the colorant in the ink. The liquid absorbing component 12J contains a liquid absorbing material as a main component. The “main component” refers to a component containing 50% by mass or more based on the whole. The liquid absorbing material means that the liquid absorbing material and the ink are mixed at a weight ratio of 30: 100 for 24 hours, and then the weight of the liquid absorbing material is equal to the weight of the liquid absorbing material when the liquid absorbing material is taken out from the mixed solution with a filter. It is increased by 5% or more compared with that before mixing.

  When the curable solution 12A contains the liquid absorbing component 12J, the ink liquid component (for example, water, aqueous solvent) is quickly taken into the resin layer and the image is fixed, so that the color mixture at the boundary between the inks In addition, image uniformity, and further, non-uniform transfer of ink due to pressure during transfer are reduced.

Examples of the liquid-absorbing material include a resin (hereinafter sometimes referred to as a liquid-absorbing resin), inorganic particles (for example, silica, alumina, zeolite, etc.) having surface ink affinity, and the ink used. It is appropriately selected depending on.
Specifically, when water-based ink is used as the ink, it is desirable to use a water-absorbing material as the liquid-absorbing material. When oil-based ink is used as the ink, it is desirable to use an oil-absorbing material as the liquid-absorbing material.

  Specific examples of the water-absorbing material include polyacrylic acid and salts thereof, polymethacrylic acid and salts thereof, (meth) acrylic acid ester- (meth) acrylic acid and salts thereof, and styrene. -Copolymer composed of (meth) acrylic acid and its salt, styrene- (meth) acrylic ester-Copolymer composed of (meth) acrylic acid and its salt, styrene- (meth) acrylic ester A copolymer composed of an ester formed from an alcohol having an aliphatic or aromatic substituent having a carboxylic acid and a salt structure thereof and (meth) acrylic acid, (meth) acrylic acid ester-carboxylic acid and a salt thereof Copolymer composed of ester formed from alcohol having aliphatic or aromatic substituent having structure and (meth) acrylic acid Copolymer composed of ethylene- (meth) acrylic acid copolymer, butadiene- (meth) acrylic ester- (meth) acrylic acid and salts thereof, butadiene- (meth) acrylic ester-carboxylic acid and salts thereof A copolymer composed of an ester formed from an alcohol having an aliphatic or aromatic substituent having a structure and (meth) acrylic acid, a polymaleic acid and a salt thereof, a copolymer composed of styrene-maleic acid and a salt thereof Examples thereof include sulfonic acid-modified products of the respective resins, phosphoric acid-modified products of the respective resins, and the like, preferably from polyacrylic acid and salts thereof, styrene- (meth) acrylic acid and salts thereof. Consists of copolymer, styrene- (meth) acrylic acid ester- (meth) acrylic acid and its salts A copolymer composed of an ester produced from (meth) acrylic acid, an alcohol having an aliphatic or aromatic substituent having a styrene- (meth) acrylic acid ester-carboxylic acid and a salt structure thereof, and (Meth) acrylic acid ester- (meth) acrylic acid and a copolymer composed of a salt thereof. These resins may be uncrosslinked or crosslinked.

  Specific examples of the oil-absorbing material include low-molecular gelling agents such as hydroxystearic acid, cholesterol derivatives, and benzylidene sorbitol, polynorbornene, polystyrene, polypropylene, styrene-butadiene copolymers, and various rosins. Desirably, polynorbornene, polypropylene, and rosins are used.

  The liquid-absorbing component 12J may be in the form of solid particles, or may be in a state where a liquid is dispersed in the cured layer 12B, such as an emulsion, or in a state in which the liquid is semi-dissolved in the curable solution 12A (for example, polymer crosslinking It may be in a state in which the molecular chain is broken and extended.

  The diameter (volume average particle diameter) of the liquid-absorbing component 12J is preferably in the range of 0.05 μm or more and 25 μm in volume average particle diameter from the viewpoint of achieving both stability of the curable solution 12A and image quality. It is more desirable that the thickness be from 05 μm to 5 μm.

  The specific gravity of the liquid absorbing component 12J is preferably relatively smaller than the specific gravity of the curable material contained in the curable solution 12A. When the intermediate transfer belt 10 and the curable layer 12B pass through the electric field generator 30, the surface 12G that receives ink is often on the upper side. In such a case, the direction in which the liquid absorbing component 12J moves due to the electric field is: The direction is against gravity. Therefore, it is preferable that the relative specific gravity of the liquid absorbing component 12J is small because the liquid absorbing component 12J easily moves in the direction of the surface 12G that receives ink.

  The ratio of the liquid-absorbing component 12J to the entire curable solution 12A is preferably 1% to 60%, more preferably 10% to 50%, and even more preferably 20% to 40% by mass ratio. . If the ratio of the liquid absorbing component 12J is too large, the viscosity of the curable solution 12A will increase, making it difficult to apply to the intermediate transfer belt 10, or reducing the image quality due to the uneven distribution of the liquid absorbing component 12J. is there. However, in this embodiment, since the liquid absorbing component 12J moves to the surface 12G that receives ink, the ink liquid absorbing property is improved without increasing the ratio of the liquid absorbing component 12J.

  When the liquid-absorbing component 12J is resin particles containing a liquid-absorbing material, examples of the resin particle adjustment method include a method of pulverizing a resin containing a liquid-absorbing material with a ball mill.

  As described above, the liquid absorbing component 12J in the curable solution 12A is charged (that is, has a property of moving in the curable solution 12A by the electric field applied by the electric field applying device 30). A preferable charge amount is 1 μC / g or more and 50 μC / g or less. Further, for example, when the charged liquid absorbing component 12J is used without being charged separately, the liquid absorbing component 12J may be added to the curable solution 12A as it is, or the liquid absorbing component 12J is charged separately. It may be added to the curable solution 12A. As a method of separately charging, friction charging with a carrier and the like can be mentioned. Furthermore, a charge control agent may be added to the liquid absorbing component 12J in order to improve the chargeability. Examples of the charge control agent include those used for known electrophotographic toners, such as Spiron Black TRH (Hodogaya Chemical Co., Ltd.), CPC (Xerox Co., Ltd.), Bontron S-34 (Orient Chemical Co., Ltd.), etc. Can be given.

―Other ingredients―
Next, other additives contained in the curable solution 12A will be described.
The curable solution 12A may include a component that aggregates or thickens the components of the ink.

  The component having this function may be included as a functional group of the resin as the liquid-absorbing material or may be included as a compound. Examples of the functional group include carboxylic acids, polyvalent metal cations, polyamines, and the like.

  Moreover, as the said compound, flocculants, such as an inorganic electrolyte, an organic acid, an inorganic acid, and an organic amine, are mentioned suitably.

  Inorganic electrolytes include alkali metal ions such as lithium ion, sodium ion, potassium ion, aluminum ion, barium ion, calcium ion, copper ion, iron ion, magnesium ion, manganese ion, nickel ion, tin ion, titanium ion, zinc Polyvalent metal ions such as ions, hydrochloric acid, odorous acid, hydroiodic acid, sulfuric acid, nitric acid, phosphoric acid, thiocyanic acid, and acetic acid, succinic acid, lactic acid, fumaric acid, fumaric acid, citric acid, salicylic acid, benzoic acid And the like, and organic carboxylic acids such as salts of organic sulfonic acids.

  The flocculant may be used alone or in combination of two or more. Moreover, as content of a flocculant, it is desirable that it is 0.01 to 30 mass%. More preferably, it is 0.1 mass% or more and 15 mass% or less, More preferably, it is 1 mass% or more and 15 mass% or less.

Further, the curable solution 12A may contain water or an organic solvent for dissolving or dispersing the main components (monomers, macromers, oligomers, prepolymers, polymerization initiators, etc.) that contribute to the curing reaction. . However, the ratio of the main component is, for example, 30% by mass or more, desirably 60% by mass or more, and more desirably 90% by mass or more.

  Further, the curable solution 12A may contain various color materials for the purpose of controlling the coloring of the cured layer.

  The viscosity of the curable solution 12A is preferably 100 mPa · s or more and 2000 mPa · s or less. The viscosity of the curable solution 12A is preferably higher than the viscosity of the ink. Further, the viscosity of the curable solution 12A constituting the curable layer 12B when an electric field is applied by the electric field applying device 30 (for example, after being heated by the heating source 32) is a viewpoint that the liquid absorbing component 12J can be easily moved. From 5 mPa · s to 1000 mPa · s is desirable, and from 10 mPa · s to 500 mPa · s is more desirable.

<Ink>
Hereinafter, details of the ink will be described.
Examples of the ink include an aqueous ink containing an aqueous solvent and a recording material, an oily ink containing an oily solvent and a recording material, an ultraviolet curable ink, and a phase change wax ink. In this embodiment, even when a water-based ink or oil-based ink is used and a non-penetrable medium is used as a recording medium, good image fixability can be obtained without volatilizing the solvent with a heater or the like.

  Examples of the water-based ink include an ink in which a water-soluble dye or pigment is dispersed or dissolved in an aqueous solvent as a recording material. Examples of the oil-based ink include an ink in which an oil-soluble dye is dissolved in an oil-based solvent as a recording material, and an ink in which a dye or pigment is dispersed by reverse micelle as a recording material.

  When using an oil-based ink, it is desirable to use an oil-based ink using a low-volatile or non-volatile solvent. Since the solvent of the oil-based ink is low volatility or non-volatility, the ink state change due to the solvent volatilization hardly occurs at the head nozzle end portion, and thus the head nozzle clogging resistance is good. Further, since the solvent of the oil-based ink is low volatility or non-volatile, even if the cured layer that has received the ink droplets is transferred to the recording medium and the solvent of the oil-based ink penetrates the recording medium, Is unlikely to occur. Further, the solvent of the oil-based ink may be a cationic curable one.

  In the present embodiment, it is desirable to use water-based ink as the ink. By using the water-based ink, the reliability of the inkjet head, maintenance, and long-term storage is improved as compared with ultraviolet curable ink and phase change ink. In this case, it is desirable to use a water absorbing material as the liquid absorbing material contained in the curable solution 12A.

  First, the recording material will be described. As the recording material, a color material is mainly used. As the coloring material, either a dye or a pigment can be used, but a pigment is desirable from the viewpoint of durability. As the pigment, both organic pigments and inorganic pigments are used. As black pigments, carbon black pigments such as furnace black, lamp black, acetylene black, and channel black can be used. In addition to black, cyan, magenta, and yellow primary pigments, specific color pigments such as red, green, blue, brown, and white, metallic luster pigments such as gold and silver, colorless or light color extender pigments, plastic pigments, etc. May be used. In addition, a newly synthesized pigment may be used for the present invention.

  In addition, there is a method of using, as a pigment, particles in which a dye or pigment is fixed on the surface of silica, alumina, polymer beads, or the like, an insoluble raked product of a dye, a colored emulsion, or a colored latex.

  Specific examples of the black pigment include Raven 7000 (manufactured by Colombian Carbon), Regal 400R (manufactured by Cabot), Color Black FW1 (manufactured by Degussa), and the like, but are not limited thereto.

  Specific examples of the cyan pigment include C.I. I. Pigment Blue-1, -2, -3, -15, -15: 1, -15: 2, -15: 3, -15: 4, -16, -22, -60, and the like. It is not limited.

  Specific examples of the magenta color pigment include C.I. I. Pigment Red-5, -7, -12, -48, -48: 1, -57, -112, -122, -123, -146, -168, -177, -184, -202, C.I. I. Pigment Violet-19 etc. are mentioned, However, It is not limited to these.

  Specific examples of yellow pigments include C.I. I. Pigment Yellow-1, -2, -3, -12, -13, -14, -16, -17, -73, -74, -75, -83, -93, -95, -97, -98, -114, -128, -129, -138, -151, -154, -180, and the like, but are not limited thereto.

  Here, when a pigment is used as the coloring material, it is desirable to use a pigment dispersant together. Examples of the pigment dispersant used include a polymer dispersant, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.

  As the polymer dispersant, a polymer having a hydrophilic structure portion and a hydrophobic structure portion is preferably used. As the polymer having a hydrophilic structure portion and a hydrophobic structure portion, a condensation polymer and an addition polymer are used. Examples of the condensation polymer include known polyester dispersants. Examples of the addition polymer include addition polymers of monomers having an α, β-ethylenically unsaturated group. Desired polymer dispersion by copolymerizing a monomer having an α, β-ethylenically unsaturated group having a hydrophilic group and a monomer having an α, β-ethylenically unsaturated group having a hydrophobic group An agent is obtained. A homopolymer of a monomer having an α, β-ethylenically unsaturated group having a hydrophilic group is also used.

  Monomers having an α, β-ethylenically unsaturated group having a hydrophilic group include monomers having a carboxyl group, a sulfonic acid group, a hydroxyl group, a phosphoric acid group, such as acrylic acid, methacrylic acid, and crotonic acid. , Itaconic acid, itaconic acid monoester, maleic acid, maleic acid monoester, fumaric acid, fumaric acid monoester, vinyl sulfonic acid, styrene sulfonic acid, sulfonated vinyl naphthalene, vinyl alcohol, acrylamide, methacryloxyethyl phosphate, bismethacrylic acid Examples include roxyethyl phosphate, methacrylooxyethyl phenyl acid phosphate, ethylene glycol dimethacrylate, and diethylene glycol dimethacrylate.

  Examples of the monomer having an α, β-ethylenically unsaturated group having a hydrophobic group include styrene derivatives such as styrene, α-methylstyrene, vinyltoluene, vinylcyclohexane, vinylnaphthalene, vinylnaphthalene derivatives, alkyl acrylate esters, Examples include methacrylic acid alkyl esters, methacrylic acid phenyl esters, methacrylic acid cycloalkyl esters, crotonic acid alkyl esters, itaconic acid dialkyl esters, maleic acid dialkyl esters, and the like.

  Examples of desirable copolymers used as polymer dispersants include styrene-styrene sulfonic acid copolymers, styrene-maleic acid copolymers, styrene-methacrylic acid copolymers, styrene-acrylic acid copolymers, Vinyl naphthalene-maleic acid copolymer, vinyl naphthalene-methacrylic acid copolymer, vinyl naphthalene-acrylic acid copolymer, alkyl acrylate ester-acrylic acid copolymer, alkyl methacrylate ester-methacrylic acid copolymer, styrene -Methacrylic acid alkyl ester-Methacrylic acid copolymer, Styrene-Acrylic acid alkyl ester-Acrylic acid copolymer, Styrene-Methacrylic acid phenyl ester-Methacrylic acid copolymer, Styrene-Methacrylic acid cyclohexyl ester-Methacrylic acid copolymer Etc. . Moreover, you may copolymerize the monomer which has a polyoxyethylene group and a hydroxyl group with these polymers.

  Examples of the polymer dispersant include those having a weight average molecular weight of 2000 to 50000.

  These pigment dispersants may be used alone or in combination of two or more. Although the amount of the pigment dispersant added varies greatly depending on the pigment, it cannot be generally stated, but generally 0.1 to 100% by mass with respect to the pigment can be mentioned.

  A pigment that self-disperses in water is also used as a colorant. The pigment that self-disperses in water refers to a pigment that has many water-solubilizing groups on the surface of the pigment and disperses in water without the presence of a polymer dispersant. Specifically, by subjecting ordinary so-called pigments to surface modification treatment such as acid / base treatment, coupling agent treatment, polymer graft treatment, plasma treatment, oxidation / reduction treatment, etc., they are self-dispersed in water. A pigment is obtained.

  Examples of the pigment that self-disperses in water include, in addition to pigments obtained by subjecting the pigment to surface modification treatment, Cab-o-jet-200, Cab-o-jet-300, IJX-157 manufactured by Cabot Corporation. IJX-253, IJX-266, IJX-273, IJX-444, IJX-55, Cab-o-jet-260M, Cab-o-jet-250C, Cab-o-jet-270Y, Cab-o-jet Commercially available self-dispersing pigments such as -1027R, Cab-o-jet-554B, Microjet Black CW-1, CW-2 manufactured by Orient Chemical Co., etc. are also used.

  The self-dispersing pigment is desirably a pigment having at least sulfonic acid, sulfonate, carboxylic acid, or carboxylate as a functional group on the surface thereof. More desirably, the pigment has at least a carboxylic acid or a carboxylate as a functional group on the surface.

  Furthermore, a pigment coated with a resin is also used. This is called a microcapsule pigment, and not only commercially available microcapsule pigments manufactured by Dainippon Ink and Chemicals, Inc., or Toyo Ink, but also microcapsule pigments produced for the present invention are used.

  In addition, a resin-dispersed pigment in which a polymer substance is physically adsorbed or chemically bonded to the pigment is also used.

  Other recording materials include hydrophilic anionic dyes, direct dyes, cationic dyes, reactive dyes, dyes such as polymer dyes and oil-soluble dyes, wax powders / resin powders and emulsions colored with dyes, Fluorescent dyes and fluorescent pigments, infrared absorbers, ultraviolet absorbers, magnetic materials such as ferromagnetic materials represented by ferrite and magnetite, semiconductors and photocatalysts represented by titanium oxide and zinc oxide, and other organic and inorganic electrons Examples include material particles.

  The content (concentration) of the recording material is, for example, in the range of 5 to 30% by mass with respect to the ink.

  Examples of the volume average particle diameter of the recording material include a range of 10 nm to 1000 nm.

  The volume average particle size of the recording material refers to the particle size of the recording material itself, or the particle size to which the additive has adhered when an additive such as a dispersant is attached to the recording material. A Microtrac UPA particle size analyzer 9340 (manufactured by Lees & Northrup) was used as the volume average particle diameter measuring apparatus. The measurement was performed according to a predetermined measurement method with 4 ml of ink placed in a measurement cell. As input values at the time of measurement, the viscosity of the ink was used as the viscosity, and the density of the dispersed particles was used as the density of the recording material.

  Next, the aqueous solvent will be described. Examples of the aqueous solvent include water. In particular, ion exchange water, ultrapure water, distilled water, and ultrafiltered water are preferably used. A water-soluble organic solvent may be used together with the aqueous solvent. As the water-soluble organic solvent, polyhydric alcohols, polyhydric alcohol derivatives, nitrogen-containing solvents, alcohols, sulfur-containing solvents and the like are used.

  Specific examples of the water-soluble organic solvent include polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,5-pentanediol, 1,2-hexanediol, 1,2, Examples thereof include sugar alcohols such as 6-hexanetriol, glycerin, trimethylolpropane, and xylitol, and sugars such as xylose, glucose, and galactose.

  Polyhydric alcohol derivatives include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, dipropylene glycol monobutyl ether, diglycerin. And ethylene oxide adducts.

Examples of the nitrogen-containing solvent include pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, and triethanolamine. Examples of the alcohol include alcohols such as ethanol, isopropyl alcohol, butyl alcohol, and benzyl alcohol.
Examples of the sulfur-containing solvent include thiodiethanol, thiodiglycerol, sulfolane, dimethyl sulfoxide and the like.

  As the water-soluble organic solvent, propylene carbonate, ethylene carbonate, and the like are also used.

  One or more water-soluble organic solvents may be used. As content of a water-soluble organic solvent, the range of 1 mass% or more and 70 mass% or less is mentioned, for example.

  Next, the oily solvent will be described. As the oily solvent, organic solvents such as aliphatic hydrocarbons, aromatic hydrocarbons, alcohols, ketones, esters, ethers, glycols, nitrogen-containing solvents, vegetable oils and the like are used. Examples of aliphatic hydrocarbons include n-hexane, cyclohexane, methylhexane, n-octane, methylheptane, dimethylhexane, nonane, decane, etc., n-paraffinic solvents such as isopar, iso-paraffinic solvents, Paraffinic solvents such as cycloparaffinic solvents may be used. Examples of the aromatic hydrocarbon include toluene, ethylbenzene, xylene and the like. Examples of alcohols include methanol, ethanol, propanol, butanol, hexanol, and benzyl alcohol. Examples of ketones include acetone, methyl ethyl ketone, pentanone, hexanone, heptanone, cyclohexanone, and the like. Examples of the esters include methyl acetate, ethyl acetate, vinyl acetate, ethyl propionate, and ethyl butyrate. Examples of ethers include diethyl ether, ethyl propyl ether, ethyl propyl ether, and ethyl isopropyl ether. Examples of glycols include ethylene glycol, diethylene glycol, propanediol, hexanediol, glycerin, and polypropylene glycol. In addition, glycol derivatives such as ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol butyl ether, diethylene glycol ethyl ether, and diethylene glycol butyl ether may be used as the solvent. Examples of vegetable oils include dry oil, semi-dry oil, and non-dry oil. Examples of the drying oil include camellia oil, linseed oil, tung oil, poppy oil, walnut oil, safflower oil, and sunflower oil. Semi-drying oil includes rapeseed oil and non-drying oil includes coconut oil. The above solvents may be used alone or in combination of two or more.

  Next, other additives will be described. In addition, a surfactant is added to the ink as necessary.

  Examples of these surfactants include various anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and the like. Desirably, anionic surfactants and nonionic surfactants are used. An activator is used.

  Surfactants may be used alone or in combination. The hydrophilic / hydrophobic balance (HLB) of the surfactant is, for example, in the range of 3 to 20 in consideration of solubility.

  The amount of the surfactant added is, for example, in the range of 0.001 to 5% by mass, desirably 0.01 to 3% by mass.

  In addition, the ink has other properties such as penetrants for adjusting penetrability, polyethyleneimine, polyamines, polyvinyl pyrrolidone, polyethylene glycol, ethylcellulose, carboxymethylcellulose, etc. In order to adjust pH, compounds of alkali metals such as potassium hydroxide, sodium hydroxide, lithium hydroxide, etc., pH buffer, antioxidant, antifungal agent, viscosity adjuster, conductive agent as necessary Further, an ultraviolet absorber and a chelating agent are also added.

  Next, preferred characteristics of the ink will be described. First, the surface tension of the ink is, for example, in the range of 20 to 45 mN / m.

  Here, as the surface tension, a value measured in an environment of 23 ° C. and 55% RH using a Wilhelmy type surface tension meter (manufactured by Kyowa Interface Science Co., Ltd.) was adopted.

  The viscosity of the ink is 1.5 mPa · s or more and 30 mPa · s or less, preferably 1.5 mPa · s or more and 20 mPa · s or less. From the viewpoint of head ejection properties, the viscosity of the ink is desirably 20 mPa · s or less. The viscosity of the ink is preferably lower than the viscosity of the curable solution 12A.

Here, as the viscosity, a value measured using a rheomat 115 (manufactured by Contraves) as a measuring device under the conditions of a measurement temperature of 23 ° C. and a shear rate of 1400 s ⁻¹ was adopted.

  The ink is not limited to the above configuration. In addition to the recording material, for example, a functional material such as a liquid crystal material or an electronic material may be included.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, these examples do not limit the present invention.

Example 1
Using a recording apparatus (see FIG. 1) having the same configuration as that of the first embodiment, a curable solution is supplied to the intermediate transfer belt by a solution supply apparatus to form a cured layer, and the cured layer is formed by a heating apparatus. An image was formed by heating, applying an electric field to the cured layer with an electric field applying device, and applying each color ink to the cured layer with a recording head. Then, while the cured layer is brought into contact with the recording medium by the transfer device, the stimulus is supplied by the stimulus supplying means for transfer, the cured layer is cured and peeled from the intermediate transfer belt, and further the stimulus is supplied by the fixing stimulus supplying means. Then, the cured layer was completely lowered and evaluated. The conditions are as follows. Note that the cumulative UV light amount for transfer below is the cumulative light amount after passing through the intermediate transfer belt.

Intermediate transfer belt: ETFE endless belt having a thickness of 0.1 mm, a belt width of 350 mm, and an outer diameter of Φ168 mm coated with a fluorine resin (process speed: 400 mm / s)
-Solution supply device: Gravure roll coater (layer thickness of cured layer 15 μm)
・ Electric field applying device: Potential difference 1.5 kV / m
Each recording head: Piezo-type recording head (resolution resolution 1200 × 1200 dpi (dpi: number of dots per inch, the same applies hereinafter), drop size 2 pL)
-Heating device: Heating system halogen heater, heating temperature 70 ° C
Transfer device (pressure roll): A steel pipe with a diameter of 30 mm coated with a fluorine resin (pressing force against the intermediate transfer belt: linear pressure 2 kgf / cm)
・ Stimulation supply device for transfer: UV-LED ultraviolet light emitting diode NCCU033 (manufactured by Nichia Corporation, peak wavelength 365 nm, UV irradiation integrated light quantity 110 mJ / cm ² irradiation)
- fixing stimulus application unit: metal halide lamp (ultraviolet irradiation integrated light intensity 510mJ / cm ² irradiation)
・ Recording media: Art paper (OK Kanfuji)

  Moreover, the curable solution and the ink of each color used what was produced as follows.

-Curable solution (radical curable material)-
-Polyurethane acrylate: 40 parts by weight-Acryloylmorpholine (UV curing monomer): 20.0 parts by weight-Sodium polyacrylate (absorbent resin, ball milled to a number average particle size of 2.5 μm, 5.6 μC / g) 35.0 parts by weight / Methylbenzoylbenzoate (photopolymerization initiator): 5 parts by weight

-Black ink-
Cab-o-jet-300 (manufactured by Cabot) was treated with an ultrasonic homogenizer for 30 minutes, and then centrifuged (7000 rpm) for 20 minutes to obtain a pigment dispersion (carbon concentration: 12.8%). Got.

Next, each of the following components was sufficiently mixed and pressure filtered through a 1 μm filter to prepare an ink. Pigment dispersion: 40 parts by weight Glycerin: 20 parts by weight Surfinol 465: 1.5 parts by weight Pure water: 35 parts by weight

—Ink Preparation Method 1—
3 parts by weight of sodium neutralized salt of styrene-maleic acid copolymer was added to 30 parts by weight of pigment, and ion exchange water was further added to make the total amount 300 parts by weight. This liquid was dispersed using an ultrasonic homogenizer. This liquid was centrifuged with a centrifugal separator to remove the remaining 100 parts by weight. The supernatant was passed through a 1 μm filter to obtain a dispersion. An appropriate amount of 10 parts by weight of glycerin, 5 parts by weight of diethylene glycol monobutyl ether, 0.03 part by weight of a surfactant, 3 parts by weight of isopropyl alcohol, ion-exchanged water and sodium hydroxide are added to an appropriate amount of the dispersion, and the total amount is 100 parts by weight. The pigment concentration was adjusted to 5% by weight. This was mixed and passed through a 1 μm filter to obtain the intended ink.

-Cyan ink-
According to the ink preparation method 1, an ink having the following composition was obtained. I. Acid Blue 199: 5 parts by weight-Styrene-maleic acid-sodium maleate copolymer: 0.3 parts by weight-Glycerin: 15 parts by weight-Diethylene glycol monobutyl ether: 5 parts by weight-Surfactant (Surfinol 465: Nissin (Chemical Co., Ltd.): 1.0 part by weight, isopropyl alcohol: 3 parts by weight, ion-exchanged water: remaining part 100 parts by weight

-Magenta ink-
According to the ink preparation method 1, an ink having the following composition was obtained. I. Acid Red 52: 3.5 parts by weight • Styrene-maleic acid-sodium maleate copolymer: 0.3 parts by weight • Glycerin: 20 parts by weight • Diethylene glycol monobutyl ether: 5 parts by weight • Surfactant (Surfinol 465: Nissin Chemical Co., Ltd.): 1.0 part by weight, ion-exchanged water: 100 parts by weight in total

-Yellow ink-
According to the ink preparation method 1, an ink having the following composition was obtained. I. Direct yellow 86: 4.0 parts by weight, styrene-maleic acid-sodium maleate copolymer: 0.4 parts by weight, glycerin: 15 parts by weight, diethylene glycol monobutyl ether: 10 parts by weight, surfactant (Surfinol 465: Nissin Chemical Co., Ltd.): 1.0 part by weight, ion-exchanged water: 100 parts by weight in total

(Example 2)
The same operation as in Example 1 was performed except that the heating apparatus was not used.

(Comparative Example 1)
It carried out similarly to Example 1 except not using a heating apparatus and an electric field provision apparatus.

<Evaluation of image quality>
The image quality of the obtained printed matter was evaluated visually. In Example 1 and Example 2, the image quality of the obtained image was better than that of Comparative Example 1. Also, in Example 2, the image quality of the obtained image was better than that in Example 1.

  Further, in the present embodiment, after the liquid absorbing component 12J of the curable layer 12B moves to the surface 12G for receiving ink by the electric field by the electric field applied by the electric field applying device 30, the ink droplet 14A is applied to the curable layer 12B. Is done. Therefore, the ink droplet 14A is largely absorbed by the liquid absorbing component 12J of the surface 12G that receives ink, and it is difficult to reach the exposed portion 12L (the portion that becomes the surface after being transferred to the recording medium P) of the cured layer 12B. It is done. That is, most of the liquid-absorbing component 12J and the ink droplets 14A are present on the surface 12G of the cured layer 12B that receives the ink. Therefore, the exposed portion exposed after the cured layer 12B is transferred to the recording medium P by the transfer device 16. The amount of the liquid absorbing component 12J and the ink droplet 14A existing in 12L is estimated to be small. Therefore, it is considered that an image with high glossiness is formed, and the exposed portion 12L functions as a protective layer, so that the image storage stability is improved.

1 is a configuration diagram illustrating a recording apparatus according to a first embodiment. FIG. 2 is a 2-2 end view of the recording apparatus according to the first embodiment. FIG. 3 is a 3-3 end view of the recording apparatus according to the first embodiment.

Explanation of symbols

10 Intermediate transfer belt (intermediate transfer member)
12 Solution supply device (curable solution layer forming means)
12A curable solution 12B cured layer (curable solution layer)
12G Surface for receiving ink 12J Liquid absorbing component 14 Inkjet recording head (applying means)
14A Ink droplet 16 Transfer device (transfer means)
18 Stimulus supply device (stimulus supply means)
28 Stimulus supply device (stimulus supply means)
30 Electric field applying device (electric field applying means)
32 Heating device (heating means)
101 Recording device P Recording medium

Claims (2)

An intermediate transfer member;
A curable solution that forms a curable solution layer by supplying a curable solution containing at least a curable material that is cured by an external stimulus and a charged liquid-absorbing component that absorbs ink onto the intermediate transfer member. Layer forming means;
An electric field applying means for applying to the curable solution layer an electric field for moving the liquid-absorbing component in the curable solution layer toward a surface of the curable solution layer that receives ink;
Ink application means for applying ink droplets to the ink receiving surface of the curable solution layer to which the electric field has been applied and the curable solution layer to which the ink droplets have been applied are brought into contact with a recording medium, and the intermediate transfer Transfer means for transferring the curable solution layer from a body to the recording medium;
And a stimulus supply means for supplying the stimulus for curing the curable solution layer to the curable solution layer.   The recording apparatus according to claim 1, further comprising a heating unit configured to heat the curable solution layer before the electric field is applied and at least one of the electric field being applied.

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