JP2019059188A - Inkjet recording method and inkjet recording device - Google Patents

Abstract

To provide a transfer type inkjet recording method having excellent transferability of an intermediate image to a recording medium and capable of stably recording a high-quality image.SOLUTION: There is provided an inkjet recording method for recording an image on a recording medium using an aqueous ink, which comprises: an intermediate image forming step of forming an intermediate image 4 by applying the aqueous ink to a transfer body 101; and a transfer step of transferring the intermediate image 4 by bringing the intermediate image 4 into contact with a recording medium 5, in this order, wherein the aqueous ink contains first resin particles 1 composed of an acrylic resin and second resin particles 2 composed of a vinyl acetate resin, and in the transfer step, the intermediate image 4 is transferred to the recording medium 5 by heating the intermediate image to a temperature higher than the glass transition temperature of at least one of the first resin particles and the second resin particles to contact with the recording medium 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inkjet recording method and an inkjet recording apparatus.

  An aqueous ink is widely used as an ink used for the inkjet recording method. In order to rapidly remove the liquid component in the ink, an ink image, which is an intermediate image, is formed on the transfer body, and after removing the liquid component contained in the intermediate image, the image is transferred onto a recording medium to record the image. There is a transfer type image recording method.

  In order to record a high quality image on a recording medium using a transfer type ink jet recording apparatus, it is required that the transferability of the intermediate image from the transfer body be good. For example, when a transfer failure in which a part of the intermediate image on the transfer body is not transferred or a transfer failure in which the intermediate image is separated inside and transferred separately to the transfer body and the recording medium occurs, The quality is reduced.

  For example, an ink jet recording method has been proposed in which a liquid containing a water-soluble resin is applied to a transfer body (Patent Document 1). In Patent Document 1, if a liquid containing a water-soluble resin is applied to the transfer body prior to the ink, the removability of the image from the transfer body is improved, and the liquid is applied to the transfer body after the ink. It is described that the adhesion of the image to the recording medium is enhanced. Further, Patent Document 2 proposes a recording method using an adhesive liquid containing a vinyl acetate resin.

JP 2005-170036 A JP, 2013-136164, A

  In order to stably record a high quality image on a recording medium using a transfer type inkjet recording apparatus, improve the transferability to the recording medium while maintaining the intermediate image formed on the transfer body in a stable state. is important. However, even with the methods proposed in Patent Documents 1 and 2, there is room for further improvement in the transferability of the intermediate image.

  Therefore, an object of the present invention is to provide a transfer type inkjet recording method which is excellent in the transferability of an intermediate image to a recording medium and capable of stably recording a high quality image on the recording medium. Another object of the present invention is to provide an ink jet recording apparatus used in the ink jet recording method.

  That is, according to the present invention, there is provided an inkjet recording method for recording an image on a recording medium using an aqueous ink, wherein the aqueous ink and, if necessary, a transfer accelerating liquid are applied to a transfer body to form an intermediate image. Forming an intermediate image, and transferring the intermediate image in contact with the recording medium in this order, and at least one of the aqueous ink and the transfer acceleration liquid is made of an acrylic resin. The water-based ink contains the first resin particles and the second resin particles composed of the vinyl acetate resin (However, when the transfer accelerating liquid is not used, the aqueous ink contains the first resin particles and the second resin particles. In the transferring step, the intermediate image is heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particles and the second resin particles, and the recording medium is contacted Was ink jet recording method characterized by transferred is provided.

  According to the present invention, it is possible to provide a transfer type inkjet recording method which is excellent in the transferability of an intermediate image to a recording medium and which can stably record a high quality image on the recording medium. Further, according to the present invention, it is possible to provide an ink jet recording apparatus used for the ink jet recording method.

FIG. 5 is a schematic view illustrating an example of a state in which an intermediate image is transferred to a recording medium. FIG. 8 is a schematic view illustrating another example of the state in which the intermediate image is transferred to the recording medium. It is a schematic diagram which shows one Embodiment of the inkjet recording device of this invention.

  Hereinafter, the present invention will be described in more detail by way of preferred embodiments. In the present invention, when the compound is a salt, the salt is dissociated into ions in the ink, but for convenience, it is expressed as “containing a salt”. Moreover, the thing of the water-based ink for inkjets may only be described as "ink." Physical property values are values at normal temperature (25 ° C.) and normal pressure (1 atm) unless otherwise specified. When described as "(meth) acrylic acid" and "(meth) acrylate", they mean "acrylic acid, methacrylic acid" and "acrylate, methacrylate", respectively.

The inventors examined the recording method proposed in Patent Documents 1 and 2. As a result, it was found that the transferability of the intermediate image from the transfer body to the recording medium was insufficient. Then, when the cause of insufficient transferability of the intermediate image was examined, it was found that there is room for ingenuity in the characteristics of the resin to be contained in the liquid. The present inventors paid attention to this point and further studied a method for improving the transferability of the intermediate image. As a result, by adopting the following requirements (i) and (ii), it is found that the transferability of the intermediate image is improved, and it becomes possible to record a high quality image, and the present invention is completed. It came to The presumed mechanism by which such an effect is obtained will be described with reference to the drawings.
(I) At least one of the aqueous ink and the transfer accelerating liquid contains a first resin particle composed of an acrylic resin and a second resin particle composed of a vinyl acetate resin.
(Ii) The intermediate image heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particle and the second resin particle is brought into contact with the recording medium and transferred.

  First, the case of using the ink containing the first resin particles and the second resin particles will be described. In the ink jet recording method of the present invention, first, as shown in FIG. 1A, the ink containing the first resin particles 1, the second resin particles 2, and the coloring material 3 is applied to the surface 10 of the transfer body 101. . Thus, an intermediate image 4 which is an ink layer containing the first resin particles 1, the second resin particles 2, and the coloring material 3 is formed on the surface 10 of the transfer body 101. Next, the recording medium 5 is brought into contact with the intermediate image 4 heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particle 1 and the second resin particle 2, and pressed as necessary (FIG. b). The intermediate image 4 may be heated in a state of being in contact with the recording medium 5 (that is, in the state of FIG. 1C). By heating the intermediate image 4 to a predetermined temperature or higher, at least one of the first resin particles 1 and the second resin particles 2 contained in the intermediate image 4 softens and flows. As a result, as shown in FIG. 1C, the contact area between the recording medium 5 and the intermediate image 4 is increased. Furthermore, by fusing at least a part of the first resin particles 1 and the second resin particles 2, the intermediate image 4 has sufficient strength, and the adhesion between the intermediate image 4 and the recording medium 5 is enhanced. As described above, if the recording medium 5 is peeled off from the transfer body 101 in a state where the adhesion between the intermediate image 4 and the recording medium 5 is enhanced, the intermediate image 4 can be transferred to the recording medium 5 with good transferability. it can.

  Next, the case of using the transfer accelerating liquid containing the first resin particles and the second resin particles will be described. First, as shown in FIG. 2A, an ink containing a coloring material 3 is applied to the surface 10 of the transfer body 101, and then a transfer acceleration liquid containing the first resin particles 1 and the second resin particles 2 is applied. Do. As a result, an intermediate image 14 composed of the ink layer containing the coloring material 3 and the transfer accelerating liquid layer containing the first resin particles 1 and the second resin particles 2 is formed on the surface 10 of the transfer body 101. Ru. Next, the recording medium 5 is brought into contact with the intermediate image 14 heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particle 1 and the second resin particle 2, and pressed as necessary (FIG. b). The intermediate image 14 may be heated in a state of being in contact with the recording medium 5 (that is, in the state of FIG. 2C). By heating the intermediate image 14 to a predetermined temperature or higher, at least one of the first resin particles 1 and the second resin particles 2 contained in the intermediate image 14 softens and flows. As a result, as shown in FIG. 2C, the contact area between the recording medium 5 and the intermediate image 14 is increased. Furthermore, by fusing at least a part of the first resin particles 1 and the second resin particles 2, the intermediate image 14 has sufficient strength, and the adhesion between the intermediate image 14 and the recording medium 5 is enhanced. As described above, when the recording medium 5 is peeled off from the transfer body 101 in a state where the adhesion between the intermediate image 14 and the recording medium 5 is enhanced, the intermediate image 14 can be transferred to the recording medium 5 with good transferability. it can.

  The temperature of the intermediate image brought into contact with the recording medium means the temperature of the intermediate image during the period in which the contact state with the recording medium is maintained from the time of contact with the recording medium to the time of peeling from the transfer body. The intermediate image may be heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particles and the second resin particles in at least a part of the period in which the contact state with the recording medium is maintained.

  When the intermediate image is heated to a temperature equal to or higher than the glass transition temperature of the second resin particle, the interaction between the resin particle and the recording medium occurs more strongly. Therefore, the adhesion between the intermediate image and the recording medium can be improved without causing a decrease in film strength due to the softening, and the transferability of the intermediate image to the recording medium can be further enhanced. In particular, when the intermediate image is heated to a temperature above the glass transition temperature of both the first resin particle and the second resin particle, the adhesion between the intermediate image and the recording medium is further improved, so that the intermediate image is transferred to the recording medium Sex can be further enhanced.

<Ink jet recording method and ink jet recording apparatus>
The inkjet recording method (hereinafter, also simply referred to as "recording method") of the present invention is a method of recording an image on a recording medium using an aqueous ink. In the recording method of the present invention, an intermediate image forming step of applying an aqueous ink and, if necessary, a transfer accelerating liquid to a transfer member to form an intermediate image, and contacting the recording medium with the intermediate image heated to a predetermined temperature And a transfer process for transferring That is, the recording method of the present invention is a transfer type ink jet recording method. Furthermore, if necessary, a reaction liquid application process of applying a reaction liquid containing a reaction agent to a transfer body, a liquid absorption process of absorbing a liquid component from an intermediate image formed on the transfer body, and a transfer body after a transfer process You may have the washing process etc. which wash.

  Further, the inkjet recording apparatus (hereinafter, also simply referred to as "recording apparatus") of the present invention is an apparatus used to record an image on a recording medium using aqueous ink. The recording apparatus according to the present invention includes an ink applying unit that discharges an aqueous ink by an inkjet method and applies it to a transfer member to form an intermediate image, and a transfer unit that transfers the intermediate image in contact with the recording medium. That is, the recording apparatus of the present invention is a so-called transfer type ink jet recording apparatus. The recording apparatus of the present invention may be provided with a transfer accelerating liquid applying means for applying a transfer accelerating liquid to a transfer body to which an aqueous ink has been applied, if necessary. Furthermore, as necessary, a reaction liquid application means for applying a reaction liquid to a transfer body, a liquid absorption means for absorbing liquid components from an intermediate image formed on a transfer body, and a washing means for washing a transfer body after transfer May be provided.

  FIG. 3 is a schematic view showing an embodiment of the ink jet recording apparatus of the present invention. A transfer type inkjet recording apparatus 100 shown in FIG. 3 is a sheet-fed type ink jet recording apparatus which transfers an ink image to a recording medium 108 via a transfer body 101 to produce a recorded matter. The X direction, the Y direction, and the Z direction indicate the width direction (full length direction), the depth direction, and the height direction of the transfer type inkjet recording apparatus 100, respectively. The recording medium is transported in the X direction.

  The transfer type inkjet recording apparatus 100 includes a transfer body 101, a reaction liquid applying apparatus 103, an applying apparatus 104, a liquid absorbing apparatus 105, and a pressing member 106. The transfer body 101 is supported by a support member 102. The reaction liquid applying apparatus 103 is an apparatus for applying a reaction liquid containing a reactive agent that reacts with the ink to the transfer member 101. The application device 104 includes a recording head that applies ink to the transfer body 101 to which the reaction liquid has been applied to form an intermediate image. The liquid absorbing device 105 is a device that absorbs the liquid component from the intermediate image. The pressing member 106 is a member for transferring the intermediate image from which the liquid component has been removed to a sheet-like recording medium 108 such as paper. Further, the transfer type inkjet recording apparatus 100 has a transfer member cleaning member 109 for cleaning the surface of the transfer member 101 after transfer. The transfer body 101, the reaction liquid applying apparatus 103, the recording head of the applying apparatus 104, the liquid absorbing apparatus 105, and the transfer body cleaning member 109 each have a length corresponding to the recording medium 108 used in the Y direction.

  The transfer body 101 rotates in the direction of arrow A around the rotation axis 102 a of the support member 102. After the reaction liquid is applied from the reaction liquid applying device 103 to the rotating transfer body 101, the ink is applied from the applying device 104 to form an intermediate image on the transfer body 101. The intermediate image formed on the transfer body 101 is moved to a position in contact with the liquid absorbing member 105 a of the liquid absorbing device 105 by the rotation of the transfer body 101.

  The liquid absorbing member 105 a constituting the liquid absorbing device 105 moves (rotates) in the direction of the arrow B in synchronization with the rotation of the transfer body 101. The intermediate image formed on the transfer member 101 contacts the moving liquid absorbing member 105 a. Meanwhile, the liquid absorbing member 105a absorbs and removes the liquid component from the intermediate image. From the viewpoint of efficiently absorbing the liquid component of the intermediate image, the liquid absorbing member 105 a is preferably pressed against the transfer body 101 with a predetermined pressing force. The intermediate image is formed of the ink, and the reaction liquid and the transfer acceleration liquid which are optionally used. For this reason, absorbing the liquid component of the intermediate image means absorbing the ink, and the liquid components of the reaction liquid and the transfer accelerating liquid used as needed. It can also be said that absorbing the liquid component from the intermediate image is to concentrate ink and the like. The concentration of the ink or the like increases the ratio to the solid component such as the color material or the resin.

  The intermediate image from which the liquid component is removed and the ink is concentrated is moved to the transfer unit 111 in contact with the recording medium 108 conveyed by the recording medium conveyance device 107 by the rotation of the transfer body 101. During this time, using the heating means such as a heater (not shown) incorporated in the support member 102 of the transfer body 101, the first resin particles contained in the ink or the transfer promoting liquid and the intermediate image on the transfer body It heats to the temperature more than the glass transition temperature of at least one of 2nd resin particle. The intermediate image may be heated by an infrared heater or the like provided at a position different from the support member. The intermediate image and the recording medium 108 are pressed from the pressing member 106 side and brought into contact with each other while being sandwiched between the transfer body 101 and the pressing member 106. When the roller-shaped transfer body 101 and the cylindrical pressing member 106 are used, the intermediate image and the recording medium 108 linearly contact along the Y direction. When the transfer body 101 made of an elastic material is used, the transfer body 101 is depressed by pressing, so that the intermediate image and the recording medium 108 come in surface contact with each other. Therefore, a line or surface where the intermediate image contacts the recording medium 108 is referred to as a “region”, and a portion including this region is referred to as a transfer portion 111. While the intermediate image is in contact with the recording medium 108, the pressing member 106 presses the transfer body 101 to transfer the intermediate image to the recording medium 108, and a desired image is recorded on the recording medium 108. The image after transfer is a reverse image of the intermediate image before transfer.

  When the reaction liquid is applied to the transfer body using the roller-shaped reaction liquid applying member 103c, the reaction liquid is applied over the entire transfer body. In order to form the intermediate image by applying the ink to the transfer body to which the reaction liquid is applied, the reaction liquid which has not reacted with the ink remains in the area on the transfer body where the ink is not applied. The liquid absorbing member 105a can remove not only the intermediate image but also the liquid component of the unreacted reaction liquid. The liquid component contained in the ink and the transfer accelerating liquid has a non-uniform shape, has fluidity, and exists in a substantially constant volume. Specifically, the liquid component contained in the ink and the transfer accelerating liquid is an aqueous medium or the like.

  The main parts of the transfer type inkjet recording apparatus will be described below. Specifically, [1] transfer body, [2] support member, [3] reaction liquid application device, [4] ink and transfer acceleration liquid application device, [5] liquid absorption device, [6] pressing member, [7] The recording medium, [8] recording medium transport device, and [9] cleaning device will be described.

[1] Transfer Member The transfer member 101 has a surface layer including a surface on which an intermediate image is formed. Resin, a ceramic, etc. can be mentioned as a material which comprises a surface layer. From the viewpoint of durability and the like, a material having a high compression elastic modulus is preferable. In order to improve the wettability of the reaction liquid, the ink, and the transfer accelerating liquid, the surface treatment may be applied.

  The transfer body preferably has a compressed layer having a function of absorbing pressure fluctuation between the surface layer and the support member. The compression layer disperses local pressure fluctuations and absorbs deformation of the surface layer. Therefore, by providing the compression layer, good transferability can be maintained even in the case of high speed recording. As a material which comprises a compression layer, elastic materials, such as a rubber material, can be mentioned. Among them, a rubber material having a porous structure formed by blending a raw material with a filler such as a foaming agent, hollow fine particles, and a salt together with a vulcanizing agent and a vulcanization accelerator is preferable. In such an elastic material, when the pressure changes, the void portion is compressed with a volume change, and therefore deformation in directions other than the compression direction is small. Therefore, transferability and durability can be improved. Examples of the porous structure include a continuous void structure in which voids are mutually connected, an independent void structure in which the voids are independent of each other, and the like.

  The transfer body preferably further has an elastic layer between the surface layer and the compression layer. As a material which comprises an elastic layer, a resin material, a ceramic material, etc. can be mentioned. Among them, elastic materials such as rubber materials are preferable because they are easy to process, the change in elastic modulus with temperature is small, and the transferability is excellent.

  The layers (surface layer, elastic layer, compression layer) constituting the transfer body can be adhered to each other using an adhesive or double-sided tape. A reinforcement layer having a high compression elastic modulus may be provided in order to suppress lateral elongation when attached to the device and maintain stiffness. A woven fabric or the like can be used as the reinforcing layer. Among the layers constituting the transfer body, elastic layers and compressed layers can be arbitrarily combined with layers other than the surface layer. The size of the transfer body can be freely selected according to the recording speed and the size of the image. Examples of the shape of the transfer body include a sheet, a roller, a belt, and an endless web.

[2] Support Member The transfer body 101 is supported on the support member 102. The transfer body can be disposed on the support using, for example, an adhesive or a double-sided tape. The transfer body 101 may be disposed on the support member 102 using an installation member made of a material such as metal, ceramic, or resin. The support member 102 is required to have a certain degree of structural strength from the viewpoint of conveyance accuracy and durability. Examples of the material of the support member include metals, ceramics, and resins. Among them, it is preferable to use a metal material such as aluminum. By using a metal material, it is possible to improve the response of control by reducing the inertia at the time of operation as well as the rigidity and the dimensional accuracy that can withstand the stress at the time of transfer.

[3] Reaction Liquid Application Device The recording method of the present invention may have a reaction liquid application step of applying the reaction liquid to the transfer member before the intermediate image forming step. The reaction liquid contains a reaction agent which reacts with the ink by coming into contact with the ink and causes the resin in the ink and the component having an anionic group such as a self-dispersion pigment to aggregate. After application of the ink, the reaction liquid may be further applied such that at least a part thereof overlaps with the area to which the ink is applied.

  The transfer type inkjet recording apparatus 100 shown in FIG. 3 has a reaction liquid applying apparatus 103 which is a reaction liquid applying means for applying a reaction liquid to the transfer member 101. The reaction liquid deposition apparatus 103 is a gravure offset roller having a reaction liquid storage section 103a for storing a reaction liquid, and reaction liquid deposition members 103b and 103c for applying the reaction liquid in the reaction liquid storage section 103a to the transfer member 101. . Examples of the reaction liquid applying apparatus include a gravure offset roller, a recording head of an ink jet system, and the like. Among them, it is preferable to apply a reaction solution to the transfer body using a roller.

[4] Application Device for Ink and Transfer Promoting Liquid The transfer type inkjet recording device 100 shown in FIG. 3 has the application device 104 for applying the ink and the transfer accelerating liquid to the transfer body 101, which is a applying means. . It is preferable to discharge and apply the ink using a recording head of an ink jet system as the applying device for applying the ink. Further, the applying means for applying the transfer accelerating liquid to the transfer body is not particularly limited, but it is preferable to discharge and apply the transfer accelerating liquid by using an ink jet recording head like the ink. As the recording head, for example, a mode in which ink is generated by causing film boiling in the ink by an electro-thermal converter to form air bubbles; a mode in which ink is discharged by an electro-mechanical converter; using static electricity And the form etc. which discharge ink etc. can be mentioned. Among them, a recording head in a form using an electro-thermal converter is preferable because it can record high-speed and high-density images.

  The recording head is a full line head extended in the Y direction, and discharge ports are arranged in a range that covers the width of the image recording area of the recording medium of the maximum size that can be used. The recording head has a discharge port surface where the discharge port is opened on the lower surface (the transfer body 101 side). The discharge port surface faces the surface of the transfer body 101 with a minute gap (about several millimeters). The application device 104 may have a plurality of recording heads in order to apply the ink of each color such as cyan, magenta, yellow, and black (CMYK) and the transfer acceleration liquid to the transfer body 101. For example, in the case of forming an intermediate image using four types of CMYK inks and a transfer acceleration liquid, the ink application device has five recording heads that respectively eject four types of CMYK inks and a transfer acceleration liquid. These recording heads are arranged along the X direction.

[5] Liquid Absorbing Device The liquid absorbing device 105 includes a liquid absorbing member 105 a and a pressing member 105 b for absorbing liquid which presses the liquid absorbing member 105 a against the ink image of the transfer member 101. In the case of the cylindrical pressing member 105b and the belt-like liquid absorbing member 105a, by pressing the liquid absorbing member 105a against the transfer body 101 by the pressing member 105b, the liquid component can be absorbed from the intermediate image. The liquid component can be absorbed from the intermediate image also by pressing a cylindrical pressing member having a liquid absorbing member attached to the outer peripheral surface thereof against the transfer body. The shape of the liquid absorbing member 105 a is preferably belt-shaped in consideration of the space in the recording apparatus. The liquid absorbing device 105 having the belt-like liquid absorbing member 105a may have a stretching member such as a stretching roller 105c that stretches the liquid absorbing member 105a.

  By bringing the liquid absorbing member 105a including the porous layer into contact with the intermediate image using the pressing member 105b, the liquid component contained in the intermediate image can be absorbed by the liquid absorbing member 105a. As a method of absorbing the liquid component contained in the intermediate image, a method of heating, a method of blowing low-humid air, a method of reducing pressure, and the like may be combined in addition to the method of contacting the liquid absorbing member. In addition, these methods may be applied to intermediate images before and after absorbing a liquid component.

  The liquid absorbing member 105 a rotates in conjunction with the rotation of the transfer body 101. For this reason, it is preferable that the shape of the liquid absorbing member 105a is a shape that can absorb liquid repeatedly, and specifically, it may be a shape such as an endless belt shape or a drum shape. The liquid component absorbed by the liquid absorbing member 105a including the porous layer is removed from the liquid absorbing member 105a by a method of absorbing from the back surface of the porous layer, a method of using a member that handles the porous member, or the like. Can. After removing the liquid component, the liquid component contained in the intermediate image can be efficiently absorbed by rotating the liquid absorbing member 105 a to bring it into contact with the new intermediate image.

[6] Pressing Member The recording apparatus of the present invention is provided with a transfer means for bringing the intermediate image into contact with the recording medium for transfer. Specifically, as shown in FIG. 3, the intermediate member after the liquid removal on the transfer body 101 is brought into contact with the recording medium 108 conveyed by the recording medium conveyance device 107 by the pressing member 106 at the transfer portion 111 and transferred. Do. By transferring the intermediate image from which the liquid component has been removed to the recording medium 108, curling or cockling of the recording medium 108 can be suppressed.

  The pressing member 106 preferably has appropriate structural strength from the viewpoint of conveyance accuracy and durability of the recording medium 108. Examples of the material of the pressing member 106 include metal, ceramic, resin and the like. Among them, metals such as aluminum are preferable from the viewpoint of reducing the inertia at the time of operation and improving the control response as well as having rigidity and dimensional accuracy that can withstand the stress at the time of transfer.

  When transferring the intermediate image to the recording medium 108, the time (pressing time) for the pressing member 106 to press the transfer body 101 is preferably 5 milliseconds or more and 100 milliseconds or less. By setting it as said pressing time, while being able to transfer favorably, damage to the transfer body 101 can be suppressed. The pressing time is the time during which the recording medium 108 and the transfer member 101 are in contact with each other. The pressing time can be calculated by measuring the surface pressure using a pressure distribution measuring system and dividing the length in the conveyance direction of the pressure area by the conveyance speed. Specifically, a contact pressure distribution measurement system (trade name “I-SCAN”, manufactured by Nitta) or the like can be used.

The pressure (pressing force) with which the pressing member 106 presses the transfer body 101 when transferring the intermediate image to the recording medium 108 is 9.8 N / cm ² (1 kg / cm ² ) or more and 294.2 N / cm ² (30 kg) It is preferable to make it / cm < ² > or less. By setting it as said pressing force, while being able to transfer favorably, damage to the transfer body 101 can be suppressed. The pressing force is a nip pressure between the recording medium 108 and the transfer body 101. The pressing force can be calculated by measuring the surface pressure using a pressure distribution measurement system and dividing the weight in the pressure area by the area. Specifically, a contact pressure distribution measurement system (trade name “I-SCAN”, manufactured by Nitta) or the like can be used.

  The temperature of the intermediate image when the pressing member 106 presses and transfers the transfer body 101 is a temperature equal to or higher than the glass transition point of at least one of the first resin particle and the second resin particle. Among them, the temperature of the intermediate image when pressing and transferring is preferably 30 ° C. or more and 180 ° C. or less, and more preferably 50 ° C. or more and 140 ° C. or less. In order to control the temperature, the recording apparatus preferably includes heating means for heating the intermediate image on the transfer body 101, the transfer body 101, and the recording medium. As a shape of the pressing member 106, for example, a shape such as a roller shape can be mentioned.

[7] Recording Medium As the recording medium 108, any known recording medium can be used. Examples of the recording medium include a long material wound in a roll, and a sheet-like material cut into a predetermined size. Examples of the constituent material of the recording medium include paper such as coated paper and plain paper; film such as plastic and metal; wood board; cardboard and the like.

[8] Recording Medium Conveying Device The recording medium conveying device 107 for conveying the recording medium 108 conveys the recording medium 108 in the direction of the arrow C. The recording medium conveyance device 107 includes a recording medium delivery roller 107 a and a recording medium take-up roller 107 b. The transport speed of the recording medium 108 is preferably determined in consideration of the speed required in each process.

[9] Cleaning Device The recording device of the present invention, as shown in FIG. 3, has a cleaning device which is a cleaning means for applying an aqueous cleaning solution to the transfer member 101 for cleaning. The cleaning apparatus includes, for example, a transfer body cleaning member 109 that applies a cleaning liquid to the transfer body 101 to clean it. By cleaning the transfer body 101 by the transfer body cleaning member 109, it is possible to suppress the deterioration of the image quality. As the cleaning member 109, one having a shape such as a roller or a web can be used. The cleaning apparatus can be provided with a cleaning liquid supply unit for supplying a cleaning liquid to the transfer member cleaning member 109.

  Furthermore, the cleaning apparatus preferably includes a cleaning solution removing member 110 for removing the cleaning solution and residue remaining on the transfer member 101 after cleaning. By removing the cleaning liquid and the like remaining on the transfer body 101 by the cleaning liquid removing member 110, it is possible to more effectively suppress the deterioration of the image quality. As a method for removing the cleaning liquid remaining on the transfer body 101, blade removal, brush removal, liquid absorption by an absorber, and the like can be mentioned. Among them, it is preferable to remove the cleaning liquid remaining on the transfer member 101 by liquid absorption by the absorber. As the cleaning liquid absorbing member 110, a porous body or the like used as a liquid absorbing member can be used.

(Ink, transfer acceleration fluid)
The ink used in the recording method of the present invention is an aqueous ink for ink jet printing that contains a coloring material. Further, the transfer accelerating liquid used as needed is a liquid for inkjet. The configuration of the transfer accelerating liquid can be the same as that of the ink except that it does not have to contain a coloring material. Hereinafter, the components used for the ink and the transfer accelerating liquid will be described in detail. In addition, although it describes as "ink" for simplicity, when using each component for a transfer acceleration | stimulation liquid, it shall read "ink" as a "transfer acceleration | stimulation liquid."

[Color material]
As a coloring material to be contained in the ink, a pigment or a dye can be used. The content (% by mass) of the coloring material in the ink is preferably 0.5% by mass or more and 15.0% by mass or less based on the total mass of the ink, and is 1.0% by mass or more and 10.0% by mass It is more preferable that it is the following.

  Specific examples of the pigment include inorganic pigments such as carbon black and titanium oxide; organic pigments such as azo, phthalocyanine, quinacridone, isoindolinone, imidazolone, diketopyrrolopyrrole and dioxazine.

  As a dispersion method of the pigment, a resin dispersion pigment using a resin as a dispersant, a self-dispersion pigment in which a hydrophilic group is bonded to the particle surface of the pigment, or the like can be used. Further, a resin-bonded pigment in which an organic group containing a resin is chemically bonded to the particle surface of the pigment, or a microcapsule pigment in which the surface of the pigment particle is coated with a resin or the like can be used.

  As a resin dispersant for dispersing the pigment in the aqueous medium, it is preferable to use one capable of dispersing the pigment in the aqueous medium by the action of the anionic group. As the resin dispersant, a resin as described later, in particular, a water-soluble resin can be used. The content (% by mass) of the pigment in the ink is preferably 0.3 times or more and 10.0 times or less by mass ratio to the content of the resin dispersant.

  As the self-dispersion pigment, one in which an anionic group such as a carboxylic acid group, a sulfonic acid group or a phosphonic acid group is bonded to the particle surface of the pigment directly or through another atomic group (-R-) is used be able to. The anionic group may be either an acid type or a salt type, and in the case of a salt type, it may be either partially dissociated or all dissociated. When the anionic group is in the form of a salt, examples of the cation serving as the counter ion include alkali metal cations, ammonium and organic ammonium. Specific examples of the other atomic group (-R-) include a linear or branched alkylene group having 1 to 12 carbon atoms; an arylene group such as a phenylene group and a naphthylene group; a carbonyl group; an imino group; an amide group; Groups; ester groups; ether groups and the like can be mentioned. Moreover, the group which combined these groups may be sufficient.

  As a dye, it is preferable to use what has an anionic group. Specific examples of the dye include dyes such as azo, triphenylmethane, (aza) phthalocyanine, xanthene and anthrapyridone. The colorant to be contained in the ink used in the recording method of the present invention is preferably a pigment, and more preferably a resin-dispersed pigment.

[resin]
A resin can be contained in the ink and the transfer accelerating liquid. The content (% by mass) of the resin in the ink or the transfer accelerating liquid is preferably 0.1% by mass or more and 20.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid. 0.5 It is more preferable that the content is not less than mass% and 15.0 mass%.

  The resin can be added to the ink (i) in order to stabilize the dispersed state of the pigment, that is, as a resin dispersant or its aid. Further, (ii) it can be added to the ink and the transfer accelerating liquid in order to improve various characteristics of the image to be recorded. As a form of resin, a block copolymer, a random copolymer, a graft copolymer, and these combination etc. can be mentioned. The resin may be a water-soluble resin that can be dissolved in an aqueous medium, or may be resin particles dispersed in an aqueous medium. The resin particles do not need to contain a coloring material.

In the present specification, "the resin is water-soluble" means that when the resin is neutralized with an alkali equivalent to the acid value, the resin is aqueous without forming particles whose particle size can be measured by the dynamic light scattering method. Means present in the medium. Whether or not the resin is water-soluble can be determined according to the method described below. First, a liquid (solid content of resin: 10% by mass) containing a resin neutralized with an alkali equivalent to an acid value (sodium hydroxide, potassium hydroxide or the like) is prepared. Next, the prepared liquid is diluted 10 times (volume basis) with pure water to prepare a sample solution. And when the particle diameter of resin in a sample solution is measured by a dynamic light scattering method, when the particle | grains which have a particle diameter are not measured, it can be judged that the resin is water solubility. The measurement conditions at this time can be, for example, as follows.
[Measurement condition]
SetZero: 30 seconds Number of measurements: 3 Measurement time: 180 seconds

  As a particle size distribution measuring apparatus, a particle size analyzer (for example, trade name “UPA-EX150” manufactured by Nikkiso Co., Ltd.) by a dynamic light scattering method can be used. Of course, the particle size distribution measuring apparatus to be used and the measuring conditions are not limited to the above.

The acid value of the water-soluble resin is preferably 100 mg KOH / g or more and 250 mg KOH / g or less. It is preferable that the acid value of resin which comprises a resin particle is 5 mgKOH / g or more and 100 mgKOH / g or less. The weight average molecular weight of the water-soluble resin is preferably 3,000 or more and 15,000 or less. The weight average molecular weight of the resin constituting the resin particles is preferably 1,000 or more and 2,000,000 or less. The average particle size (volume-based 50% cumulative particle size (D ₅₀ )) of the resin particles measured by the dynamic light scattering method is preferably 50 nm or more and 500 nm or less.

  As resin, acrylic resin, urethane resin, olefin resin etc. can be mentioned. Among them, acrylic resins and urethane resins are preferable.

  As an acrylic resin, what has a hydrophilic unit and a hydrophobic unit as a structural unit is preferable. Among them, a resin having a hydrophilic unit derived from (meth) acrylic acid and a hydrophobic unit derived from at least one of a monomer having an aromatic ring and a (meth) acrylic acid ester-based monomer is preferable. In particular, a resin having a hydrophilic unit derived from (meth) acrylic acid and a hydrophobic unit derived from at least one monomer of styrene and α-methylstyrene is preferable. These resins are likely to interact with the pigment, and can be suitably used as a resin dispersant for dispersing the pigment.

  The hydrophilic unit is a unit having a hydrophilic group such as an anionic group. The hydrophilic unit can be formed, for example, by polymerizing a hydrophilic monomer having a hydrophilic group. Specific examples of the hydrophilic monomer having a hydrophilic group include acid monomers having a carboxylic acid group such as (meth) acrylic acid, itaconic acid, maleic acid and fumaric acid, and anions such as anhydrides and salts of these acidic monomers And the like. As a cation which comprises the salt of an acidic monomer, ions, such as lithium, sodium, potassium, ammonium, organic ammonium, can be mentioned. The hydrophobic unit is a unit having no hydrophilic group such as an anionic group. The hydrophobic unit can be formed, for example, by polymerizing a hydrophobic monomer having no hydrophilic group such as an anionic group. Specific examples of the hydrophobic monomer include monomers having an aromatic ring such as styrene, α-methylstyrene and benzyl (meth) acrylate; methyl (meth) acrylate, butyl (meth) acrylate and (meth) acrylic acid 2 -(Meth) acrylic acid ester type monomers, such as ethylhexyl, etc. can be mentioned.

  The urethane resin can be obtained, for example, by reacting a polyisocyanate and a polyol. Further, it may be one further reacted with a chain extender. As an olefin resin, polyethylene, a polypropylene, etc. can be mentioned, for example.

[First resin particle]
At least one of the aqueous ink and the transfer accelerating liquid used in the recording method of the present invention contains a first resin particle composed of an acrylic resin and a second resin particle composed of a vinyl acetate resin. However, when the transfer accelerating liquid is not used (when the recording apparatus does not have the transfer accelerating liquid applying means), the aqueous ink contains the first resin particles and the second resin particles.

  The first resin particles are made of an acrylic resin. As a structural unit of acrylic resin, acrylic units, such as a hydrophilic unit derived from the above-mentioned (meth) acrylic acid etc., and a hydrophobic unit derived from a (meth) acrylic acid ester monomer etc., can be mentioned. . The acrylic resin may further have a unit derived from a monomer having an aromatic ring or a monomer having an amide group, as long as it has the above-mentioned acrylic unit.

  Various physical properties such as the acid value, weight average molecular weight, average particle size and the like of the first resin particles can be appropriately determined within the above-mentioned range. The glass transition temperature (Tg) of the first resin particles is preferably 0 ° C. or more and 180 ° C. or less, and more preferably 30 ° C. or more and 140 ° C. or less. The glass transition temperature Tg (° C.) of the resin particles can be measured, for example, according to JIS K 6240: 2011, by a conventional method using a thermal analyzer such as a differential scanning calorimeter (DSC).

  The content (% by mass) of the first resin particles in the ink or the transfer accelerating liquid is preferably 0.5% by mass or more and 20.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid, More preferably, it is 1.0% by mass or more and 15.0% by mass or less.

[Second resin particle]
The second resin particles are made of vinyl acetate resin. Examples of the vinyl acetate resin include homopolymers of vinyl acetate; copolymers of vinyl acetate with various monomers other than vinyl acetate such as olefin and vinyl halide. Among these, ethylene-vinyl acetate copolymer is preferable.

  Various physical properties such as the acid value, weight average molecular weight and average particle size of the second resin particles can be appropriately determined within the range described above. The glass transition temperature (Tg) of the second resin particles is preferably −20 ° C. or more and 150 ° C. or less, and more preferably 15 ° C. or more and 100 ° C. or less.

  The content (% by mass) of the second resin particles in the ink or the transfer accelerating liquid is preferably 0.5% by mass or more and 20.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid, More preferably, it is 1.0% by mass or more and 15.0% by mass or less.

  The content (% by mass) of the first resin particles in the ink or the transfer acceleration liquid is 0.20 times to 5.00 times by mass ratio with respect to the content (% by mass) of the second resin particles Is preferred. If the above mass ratio is less than 0.20 times, the film strength of the intermediate image may be slightly reduced and the transferability improvement effect may be slightly reduced because the first resin particles are relatively small. On the other hand, if the above mass ratio is more than 5.00 times, the adhesion of the intermediate image to the recording medium is slightly reduced and the improvement of the transferability is slightly reduced because the second resin particles are relatively small. There is a case.

  The average particle size of the first resin particles is preferably smaller than the average particle size of the second resin particles. When the first resin particles and the second resin particles are used in a combination in which the average particle diameter has such a relationship, the transferability can be further improved.

[Water-soluble acrylic resin]
The ink and the transfer accelerating solution preferably contain a water-soluble acrylic resin. As a structural unit of acrylic resin, acrylic units, such as a hydrophilic unit derived from the above-mentioned (meth) acrylic acid etc., and a hydrophobic unit derived from a (meth) acrylic acid ester monomer etc., can be mentioned. . The acrylic resin may further have a unit derived from a monomer having an aromatic ring or a monomer having an amide group, as long as it has the above-mentioned acrylic unit. Physical properties such as the acid value and weight average molecular weight of the water-soluble acrylic resin, and the content thereof can be appropriately determined within the above-mentioned range.

[Aqueous medium]
The ink used in the recording method of the present invention is an aqueous ink containing at least water as an aqueous medium. Further, the transfer accelerating liquid, which is optionally used in the recording method of the present invention, is preferably an aqueous liquid containing at least water as an aqueous medium. The ink and the transfer accelerating solution may contain an aqueous medium which is water or a mixed solvent of water and a water-soluble organic solvent. As water, it is preferable to use deionized water or ion exchange water. The content (% by mass) of water in the aqueous ink or the transfer accelerating liquid is preferably 50.0% by mass or more and 95.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid. In addition, the content (% by mass) of the water-soluble organic solvent in the aqueous ink or the transfer promoting liquid is 3.0% by mass or more and 50.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid. Is preferred. As the water-soluble organic solvent, any of the alcohols, (poly) alkylene glycols, glycol ethers, nitrogen-containing compounds, sulfur-containing compounds and the like that can be used for ink jet inks can be used.

[Other additives]
In addition to the above components, the ink and the transfer accelerating liquid may each optionally contain an antifoaming agent, a surfactant, a pH adjuster, a viscosity adjuster, an antirust agent, an antiseptic agent, an antifungal agent, and an antioxidant. You may contain various additives, such as a reduction inhibitor.

  The ink and the transfer accelerating liquid preferably contain, as additives, a compound having a block structure composed of an ethylene oxide unit and a propylene oxide unit. Such a compound forms a hydrogen bond with a component such as a resin having an anionic group. As a result, the intermediate image is easily aggregated, the transferability is further improved, and the image movement can be suppressed. The content (% by mass) of the compound in the ink or the transfer accelerating liquid is preferably 0.2% by mass or more and 5.0% by mass or less based on the total mass of the ink or the transfer accelerating liquid, and More preferably, it is 0% by mass or more and 4.0% by mass or less.

(Reaction liquid)
The recording method of the present invention preferably further comprises a reaction liquid applying step of applying an aqueous reaction liquid containing a reactive agent that reacts with the aqueous ink to the transfer body. It is preferable that this reaction liquid application process is a process before the intermediate image forming process. The reaction liquid reacts with the ink by coming into contact with the aqueous ink, and aggregates components (components having an anionic group such as a resin and a self-dispersion pigment) in the ink, thereby forming an aqueous liquid containing a reactive agent. It is. Examples of the reactive agent include polyvalent metal ions, cationic components such as cationic resins, and organic acids. Among them, the reactive agent is preferably an organic acid.

Examples of polyvalent metal ions include divalent metal ions such as Ca ²⁺ , Cu ²⁺ , Ni ²⁺ , Mg ²⁺ , Sr ²⁺ , Ba ²⁺ , and Zn ²⁺ , Fe ³⁺ , and the like. Mention may be made of trivalent metal ions such as Cr ³⁺ , Y ³⁺ and Al ³⁺ . In order to cause the reaction solution to contain polyvalent metal ions, polyvalent metal salts (which may be hydrates) formed by combining polyvalent metal ions and anions can be used. The anion such ^{as, Cl -, Br -, I} -, ClO -, ClO 2 -, ClO 3 -, ClO 4 -, NO 2 -, NO 3 -, SO 4 2-, CO 3 2-, HCO 3 _{^{-, PO 4 3-, HPO 4}} 2-, and H ₂ PO ₄ ^- inorganic anions such ^{as; HCOO -, (COO -)} 2, COOH (COO -), CH 3 COO -, C 2 H 4 (COO - _{) 2, C 6 H 5 COO} -, C 6 H 4 (COO -) 2, and CH ₃ SO ₃ ^- may be mentioned organic anion such. When using a polyvalent metal ion as a reaction agent, the content (mass%) in terms of polyvalent metal salt in the reaction liquid is 1.0 mass% or more and 40.0 mass% or less based on the total mass of the reaction liquid Is preferred.

  The reaction liquid containing an organic acid has an acid capacity (a pH of less than 7.0, preferably a pH of 2.0 to 5.0), so that the anionic group of the component present in the ink can be efficiently formed by having a buffering capacity. To aggregate. Examples of organic acids include formic acid, acetic acid, propionic acid, butyric acid, benzoic acid, glycolic acid, lactic acid, salicylic acid, pyrrolecarboxylic acid, furancarboxylic acid, picolinic acid, nicotinic acid, thiophenecarboxylic acid, levulinic acid, coumaric acid, etc. Monocarboxylic acids and salts thereof; oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, itaconic acid, sebacic acid, phthalic acid, malic acid, dicarboxylic acids such as tartaric acid, and salts thereof And hydrogen salts; tricarboxylic acids such as citric acid and trimellitic acid and salts and hydrogen salts thereof; tetracarboxylic acids such as pyromellitic acid and salts and hydrogen salts thereof. The content (% by mass) of the organic acid in the reaction liquid is preferably 1.0% by mass or more and 50.0% by mass or less based on the total mass of the reaction liquid.

  Examples of the cationic resin include resins having a structure of primary to tertiary amines and resins having a structure of quaternary ammonium salts. Specifically, resins having structures such as vinylamine, allylamine, vinylimidazole, vinylpyridine, dimethylaminoethyl methacrylate, ethyleneimine, guanidine and the like can be mentioned. In order to enhance the solubility in the reaction solution, the cationic resin and the acidic compound may be used in combination, or the quaternization treatment of the cationic resin may be performed. When a cationic resin is used as a reaction agent, the content (% by mass) of the cationic resin in the reaction liquid is 1.0% by mass or more and 10.0% by mass or less based on the total mass of the reaction liquid preferable.

[Resin particle]
The reaction solution preferably contains resin particles. By using a reaction liquid containing resin particles, transfer failure is further suppressed, and a higher quality image can be recorded. Examples of the resin particles to be contained in the reaction solution include acrylic resins, urethane resins, olefin resins such as polyethylene and polypropylene, paraffin wax, carnauba wax and the like. The content (% by mass) of resin particles in the reaction liquid is preferably 3.0% by mass or more and 30.0% by mass or less based on the total mass of the reaction liquid, and is 5.0% by mass or more and 20.0%. It is further preferable that the content is at most mass%.

[Other ingredients]
The reaction solution may contain various other components as needed. Examples of other components include the same as the above-mentioned aqueous medium and other additives that can be contained in the ink.

  Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but the present invention is not limited at all by the following examples as long as the gist thereof is not exceeded. Those described as "parts" and "%" in terms of component amounts are on a mass basis unless otherwise specified.

<Analytical conditions>
Various physical properties of the resin particles were measured according to the conditions shown below in an environment of temperature 25 ° C., relative humidity 50%, and 1 atm.

(50% particle size based on volume distribution)
Ion exchange water was added to the liquid containing the material to be measured to prepare a sample having a solid content of about 1.0%. Using a particle size analyzer (trade name "UPA-EX150" manufactured by Nikkiso Co., Ltd.) with a dynamic light scattering method for the prepared sample, 50% particle diameter (D ₅₀ ) was measured. In addition, resin in which the particle diameter was not measured by this method is judged to be "water-soluble" resin.
[Measurement condition]
SetZero: 30 seconds Number of measurements: 3 Measurement time: 180 seconds, refractive index: 1.5

(Glass-transition temperature)
Using a differential scanning calorimeter (trade name "Q1000", manufactured by TA Instruments), the glass transition temperature (Tg) of the resin particles was determined for the sample obtained by drying the aqueous dispersion of the resin particles. It was measured. In the measurement, a cycle of measurement was performed twice by raising the temperature from -70 ° C to 180 ° C at a rate of 10 ° C / min.

<Preparation of water soluble resin>
(Water-soluble resin 1)
A styrene-ethyl acrylate-acrylic acid copolymer (water-soluble resin 1) having an acid value of 150 mg KOH / g and a weight average molecular weight of 8,000 was prepared. After neutralizing 20.0 parts of water-soluble resin 1 with potassium hydroxide equivalent to its acid value and an appropriate amount of pure water, a water-soluble resin having a resin (solid content) content of 20.0% An aqueous solution of Resin 1 was prepared.

(Water-soluble resin 2)
A benzyl methacrylate-butyl acrylate-acrylic acid copolymer (water-soluble resin 2) having an acid value of 120 mg KOH / g and a weight average molecular weight of 7,000 was prepared. After neutralizing 20.0 parts of water-soluble resin 2 with potassium hydroxide equivalent to its acid value and an appropriate amount of pure water, a water-soluble resin having a resin (solid content) content of 20.0% An aqueous solution of Resin 2 was prepared.

<Preparation of pigment dispersion>
A mixture was obtained by mixing 10.0 parts of a pigment (carbon black), 15.0 parts of an aqueous solution of the water-soluble resin 1, and 75.0 parts of pure water. The obtained mixture and 200 parts of 0.3 mm diameter zirconia beads were placed in a batch-type vertical sand mill (manufactured by Imex) and dispersed for 5 hours while cooling with water. After centrifuging to remove coarse particles, pressure filtration is performed with a cellulose acetate filter (manufactured by Advantec) with a pore size of 3.0 μm, and the content of the pigment is 10.0%, and the content of the resin dispersant (resin 1) A pigment dispersion having an amount of 3.0% was prepared.

<Preparation of resin particles>
(Resin particle 1)
In a four-necked flask equipped with a stirrer, a reflux condenser, and a nitrogen gas inlet pipe, 74.0 parts of ion exchange water and 0.2 parts of potassium persulfate were added and mixed. Also, 24.0 parts of butyl methacrylate, 1.5 parts of methacrylic acid, and 0.3 parts of a reactive surfactant (trade name "Aqualon KH-05", manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) are mixed to prepare an emulsion. did. Under a nitrogen atmosphere, the prepared emulsion was dropped into the above four-necked flask over 1 hour, and a polymerization reaction was performed for 2 hours while stirring at 80 ° C. After cooling to 25 ° C., ion-exchanged water and an aqueous solution containing potassium hydroxide equimolar to the acid value of the resin particles are added, and the resin particles (solid content) content is 25.0%. A water dispersion of 1 was prepared. The D _{50 of the} resin particle 1 was 220 nm, and the Tg was 30 ° C.

(Resin particle 2)
An aqueous dispersion of resin particles 2 having a resin particle (solid content) content of 25.0% was prepared in the same manner as the above-described resin particles 1 except that butyl methacrylate was changed to ethyl methacrylate. The D _{50 of the} resin particles 2 was 210 nm, and the Tg was 60 ° C.

(Resin particle 3)
An aqueous dispersion of resin particles 3 having a resin particle (solid content) content of 25.0% was prepared in the same manner as the above-described resin particles 1 except that butyl methacrylate was changed to methyl methacrylate. The D _{50 of the} resin particles 3 was 230 nm, and the Tg was 100 ° C.

(Resin particle 4)
Resin particles (trade name "Sumika flex 755", manufactured by Sumitomo Chemical Co., Ltd.) composed of ethylene-vinyl acetate copolymer are diluted with ion-exchanged water, and the content of resin particles (solid content) is 25.0%. An aqueous dispersion of certain resin particles 4 was prepared. The D _{50 of the} resin particles 4 was 470 nm, and the Tg was −15 ° C.

(Resin particle 5)
Resin particles (trade name "Sumikaflex 752", manufactured by Sumitomo Chemical Co., Ltd.) composed of ethylene-vinyl acetate copolymer are diluted with ion-exchanged water, and the content of resin particles (solid content) is 25.0%. An aqueous dispersion of certain resin particles 5 was prepared. The D _{50 of the} resin particles 5 was 475 nm, and the Tg was 15 ° C.

(Resin particle 6)
Resin particles (solid content) content is 25.0% by diluting resin particles (trade name "Vinibran 1002", manufactured by Nisshin Chemical Co., Ltd.) composed of modified vinyl acetate resin with ion exchange water A water dispersion of 6 was prepared. The D _{50 of the} resin particles 6 was 160 nm, and the Tg was 30 ° C.

(Resin particle 7)
A resin in which the content of resin particles (solid content) is 25.0% by diluting resin particles (trade name “Vinibran GV-6181”, manufactured by Nisshin Chemical Co., Ltd.) composed of vinyl acetate resin with ion exchanged water An aqueous dispersion of particles 7 was prepared. The D _{50 of the} resin particles 7 was 1,400 nm, and the Tg was 30 ° C.

(Resin particle 8)
The resin particles (trade name "Binibran 603", manufactured by Nisshin Chemical Co., Ltd.) composed of a copolymer resin of vinyl chloride-vinyl acetate are diluted with ion exchange water, and the content of resin particles (solid content) is 25.0. % Aqueous dispersion of resin particles 8 was prepared. The D _{50 of the} resin particles 8 was 128 nm, and the Tg was 58 ° C.

<Preparation of ink and transfer acceleration liquid>
After mixing each component (unit:%) shown in Tables 1-1 and 1-2 and sufficiently stirring, pressure filtration is performed with a cellulose acetate filter (made by Advantec) with a pore size of 3.0 μm, and the ink and transfer acceleration are performed. The solution was prepared. The numerical value attached to polyethylene glycol is the number average molecular weight of polyethylene glycol. In Tables 1-1 and 1-2, "Pluronic L-31" is a trade name of a block copolymer of ethylene oxide-propylene oxide manufactured by ADEKA. "Acetylenol E100" is a trade name of a surfactant manufactured by Kawaken Fine Chemicals Co., Ltd.

<Preparation of Reaction Solution>
Each component (unit:%) shown in Table 2 was mixed, and after sufficient stirring, pressure filtration was performed using a cellulose acetate filter (manufactured by Advantec) with a pore size of 3.0 μm to prepare a reaction liquid. In Table 2, "Megafuck F 444" is a trade name of surfactant manufactured by DIC.

<Evaluation>
The ink, the transfer accelerating liquid, and the reaction liquid were a set of combinations shown in Table 3. Then, an image was recorded using the transfer type inkjet recording apparatus 100 shown in FIG. As the support member 102, a cylindrical drum made of an aluminum alloy was used. As a surface member of the transfer body 101, a film of polyethylene terephthalate having a thickness of 0.5 mm, a rubber hardness (durometer type A), 40 ° silicone rubber (trade name "KE12", manufactured by Shin-Etsu Chemical Co., Ltd.) of 0.2 mm What was coated to thickness was used.

  A plasma surface treatment is performed on the surface member using a normal pressure plasma treatment apparatus (trade name "ST-7000", manufactured by Keyence) under the conditions of 5 mm in processing distance, High in plasma mode, and 100 mm / sec in processing speed. gave. Further, the surface member is immersed in a surfactant aqueous solution prepared by diluting with pure water so that the concentration of a commercially available neutral detergent (sodium alkylbenzene sulfonate) becomes 3%, and then dried. The surface member of the transfer body 101 was used. The transfer body 101 was fixed to the support member 102 using a double-sided adhesive tape.

In the case of using the reaction liquid, the reaction liquid applying apparatus 103 was used to apply the reaction liquid to the transfer body 101 so as to be 1.0 g / m ² . As the application device 104 for the ink and the transfer accelerating liquid, a recording head of a type which ejects the ink by an on-demand method having an electro-thermal conversion element was used.

  After compression molding of the emulsion-polymerized particles of the crystallized fluororesin (polytetrafluoroethylene), it was drawn at a temperature below the melting point to prepare a fibrillated porous layer (first layer). Furthermore, polyethylene and polypropylene were mixed and then stretched by a wet method to produce a fibrillated porous layer (second layer). In addition, a polyolefin-based non-woven fabric (trade name "HOP60, manufactured by Ayase Paper Co., Ltd.) was used as the third layer. The thickness of the layer is thicker in the second layer than in the first layer. Also, the average pore size is smaller in the second layer than in the first layer. The first layer, the second layer, and the third layer were bonded by hot pressure lamination to obtain a porous body.

  This porous body was used as a liquid absorbing member 105a. The movement speed of the liquid absorbing member 105 c was adjusted by controlling the rotation speed of the transport roller 105 c so as to be equal to the rotation speed of the transfer member 101. The moving speed of the liquid absorbing member 105c was 0.4 m / sec. The liquid absorbing member 105a is immersed in a liquid containing 95.0 parts of ethanol and 5.0 parts of water to make the pores of the porous body permeate the liquid, and then the inside of the pores is replaced with water and used for liquid removal did.

The recording medium delivery roller 107 a and the recording medium take-up roller 107 b were driven to convey the recording medium 108 so as to have a speed equal to the moving speed of the transfer member 101. The transfer body 101 was heated by a heater incorporated in the transfer body 101 and was heated until the temperature of the intermediate image reached the temperature shown in Table 3. Then, the recording medium 108 and the intermediate image were brought into contact with each other between the transfer body 101 and the pressing member 106, and the intermediate image was transferred from the transfer body 101 to the recording medium 108 to record a solid image. As the recording medium 108, coated paper (trade name "Vannubo V", manufactured by Daio Paper Products, basis weight 157 g / m ² ) was used. The nip pressure between the transfer body 101 and the pressing member 106 was adjusted to 3 kg / cm ² .

  A 5 cm × 5 cm solid image having a recording duty of 200% was recorded using the transfer type inkjet recording apparatus 100 having the above configuration. Specifically, when the transfer promoting liquid was not used, a solid image of 5 cm × 5 cm in which the recording duty of the ink was 200% was formed on the transfer body 101 as an intermediate image. Further, in the case of using the ink and the transfer accelerating liquid, a solid image of 5 cm × 5 cm in which each recording duty is 100% was formed on the transfer body 101 as an intermediate image. In the transfer type inkjet recording apparatus 100, an image recorded under the condition of applying one drop of 3.0 ng ink droplet to a unit area of 1/1200 inch × 1/1200 inch is defined as having a recording duty of 100%. In the present invention, “AA”, “A” and “B” are acceptable levels, and “C” is unacceptable level, in the evaluation criteria of the following items. The evaluation results are shown in Table 3.

(Transferability)
The surface of the transfer body before and after the transfer step was observed with an optical microscope, and the area x of the intermediate image on the transfer body before transfer and the area y of the intermediate image remaining on the transfer body after transfer were calculated. Then, the transfer rate was calculated from the following equation, and the transferability was evaluated according to the evaluation criteria shown below.
Transfer ratio (%) = {1- (y / x)} × 100 (%)
AA: The transfer rate was 95% or more.
A: The transfer rate was 90% or more and less than 95%.
B: The transfer rate was 80% or more and less than 90%.
C: The transfer rate was less than 80%.

(Image movement)
The presence or absence of color loss in the recorded solid image was observed with an optical microscope, and image movement was evaluated according to the evaluation criteria shown below. When the evaluation of the transferability is “C”, it is difficult to evaluate the image recorded on the recording medium, so the intermediate image formed on the transfer body was observed and evaluated.
AA: There was no loss of color.
A: There was color loss but it was an image recognized as a solid image.
B: A solid image could not be recorded.

Claims (8)

An inkjet recording method for recording an image on a recording medium using an aqueous ink, comprising:
An intermediate image forming step of forming an intermediate image by applying the aqueous ink and, if necessary, a transfer accelerating liquid to a transfer body;
And v. Transferring the intermediate image in contact with the recording medium for transfer.
At least one of the aqueous ink and the transfer promoting liquid contains a first resin particle composed of an acrylic resin and a second resin particle composed of a vinyl acetate resin (however, when the transfer promoting liquid is not used) (Wherein the aqueous ink contains the first resin particles and the second resin particles),
In the transfer step, the intermediate image is heated to a temperature equal to or higher than the glass transition temperature of at least one of the first resin particle and the second resin particle, and brought into contact with the recording medium for transfer. Ink jet recording method.   The ink jet recording method according to claim 1, further comprising a reaction liquid applying step of applying an aqueous reaction liquid containing a reactive agent that reacts with the aqueous ink to the transfer body.   The content (% by mass) of the first resin particles in the aqueous ink or the transfer accelerating liquid is 0.20 or more times by 5.00 as a mass ratio with respect to the content (% by mass) of the second resin particles. The ink jet recording method according to claim 1 or 2, which is not more than double.   The ink jet recording method according to any one of claims 1 to 3, wherein the aqueous ink or the transfer accelerating liquid contains a water-soluble acrylic resin.   The inkjet recording method according to any one of claims 1 to 4, wherein an average particle diameter of the first resin particles is smaller than an average particle diameter of the second resin particles.   The inkjet recording according to any one of claims 1 to 5, wherein in the transfer step, the intermediate image is heated to a temperature equal to or higher than the glass transition temperature of the second resin particles, and brought into contact with the recording medium for transfer. Method.   The transfer process according to any one of claims 1 to 6, wherein the intermediate image is heated to a temperature equal to or higher than the glass transition temperature of both the first resin particle and the second resin particle, and brought into contact with the recording medium for transfer. The inkjet recording method according to any one of the preceding items. An inkjet recording apparatus used to record an image on a recording medium using an aqueous ink, comprising:
An ink applying unit that discharges the aqueous ink by an inkjet method and applies it to a transfer body to form an intermediate image;
A transfer unit for bringing the intermediate image into contact with the recording medium for transfer;
Further, as required, a transfer accelerating liquid applying unit may be provided to apply a transfer accelerating liquid to the transfer body to which the aqueous ink is applied.
At least one of the aqueous ink and the transfer promoting liquid contains a first resin particle composed of an acrylic resin and a second resin particle composed of a vinyl acetate resin (provided that the transfer promoting liquid applying means is provided) If not, the aqueous ink contains the first resin particles and the second resin particles),
An inkjet recording apparatus, further comprising a heating unit capable of heating the intermediate image to a temperature equal to or higher than a glass transition temperature of at least one of the first resin particle and the second resin particle.

Images