JP4826395B2 - Recording device - Google Patents

Description

  The present invention relates to a recording apparatus.

  There is an ink jet recording method in which an image or data using ink is recorded. The principle of the ink jet recording system is to record on paper, cloth, film, etc. by discharging liquid or molten solid ink from a nozzle, slit, porous film or the like. As for the method for ejecting ink, the so-called charge control method in which ink is ejected using electrostatic attraction, the so-called drop-on-demand method (pressure pulse method) in which ink is ejected using the vibration pressure of a piezo element. Various methods have been proposed, such as a so-called thermal ink jet method, in which ink is ejected using pressure generated by the formation and growth of bubbles due to high heat. By these methods, extremely high-definition images and data are Records can be obtained.

  In order to record with high image quality on various recording media such as penetrating media and non-penetrating media, recording methods using ink, including this ink jet recording method, are recorded on an intermediate and then transferred to the recording medium. A scheme has been proposed.

  For example, Patent Document 1 proposes a method for recording while supplying a plurality of types of powder mixtures onto an intermediate, such as polymers having different water absorption, water absorbing polymers having different sizes, and water absorbing polymers having different crosslinking degrees. Yes.

  Patent Document 2 proposes a method of recording while supplying solid particles (particles of polysaccharide polymer, alginic acid, carrageenan, etc.) that thicken the ink by contact with the ink on the intermediate.

  Further, in Patent Document 3, a hydrophobic resin particle layer is formed on an intermediate, and ink (for example, an SD type dye ink slow dry type (Slow Dry type)) is held in the voids of the hydrophobic resin particle layer. A method of transferring to a recording medium has been proposed.

  Patent Document 4 proposes a method in which a gap type ink absorption layer in which inorganic particles, a hydrophilic polymer, and the like are wet-coated is provided on an intermediate body (sheet), and dye ink is ejected thereon and transferred to a recording medium. Has been.

  Patent Document 5 discloses a porous ink absorbing layer formed by drying at a temperature not higher than the minimum film-forming temperature (MFT) of thermoplastic resin particles, which contains thermoplastic resin particles and non-thermoplastic particles. Inkjet intermediate transfer media having been proposed.

  In Patent Document 6, a powder that is thickened by contact with a liquid using a high electric resistance material is supplied onto an intermediate transfer body, and then an image is formed by bringing the liquid into contact with the powder to form an image on the intermediate transfer body. There has been proposed a recording apparatus for transferring a thickened image onto a transfer medium.

Patent Document 7 discloses a liquid ejected from a liquid ejecting apparatus by previously forming a powder that shows solubility or swelling with respect to a droplet and can increase the viscosity of the droplet on an intermediate transfer member. A recording apparatus has been proposed in which droplets reach the intermediate transfer member, and the powder is dissolved or swollen by the droplets, and the droplets having a high viscosity by the powder are transported to the transfer portion by the intermediate transfer member and transferred onto the recording paper. .
JP 2000-343808 JP 2000-94654 A JP 2003-57967 A JP 2002-370347 JP 2002-321443 A JP 2001-321443 A JP-A-11-188858

  An object of the present invention is to provide a recording apparatus capable of continuously forming images while preventing image disturbance.

The above problem is solved by the following means. That is,
The invention according to claim 1
An intermediate transfer member;
A release agent supply means for supplying a release agent onto the intermediate transfer member;
Particle supplying means for supplying hydrophilic ink receiving particles for receiving ink onto a release agent supplied on the intermediate transfer member;
An ink discharge means for discharging ink to the ink receiving particles supplied on the intermediate transfer member;
Transfer means for transferring the ink receiving particles that have received the ink from an intermediate transfer member to a recording medium;
Have
The releasing agent is, the recording apparatus is an organic compound of soluble Kaido parameter (SP value) 8-11.

The invention according to claim 2
The recording apparatus according to claim 1, wherein the solubility parameter (SP value) of the organic compound is 8 to 10.

The invention according to claim 3
The viscosity of the releasing agent is a recording apparatus according to claim 1 or 2 which is 5~200mPa · s.

The invention according to claim 4
The ink receptive particles are recorded according to the polar monomer claims 1 to 3 any one ratio is contains at least constituting 10 mol% or more 90 mol% or less of the organic resin for total monomer components Device.

  According to the first aspect of the present invention, there is an effect that images can be continuously formed while preventing image distortion even when hydrophilic ink-receptive particles are used, as compared with the case without this configuration.

According to the invention of claim 2 , compared to the case without this configuration, the ink is suppressed from being mixed with the release agent, the image density is maintained, and hydrophilic ink receiving particles are used. There is an effect that images can be continuously formed while preventing image disturbance and optical density reduction.

According to the third aspect of the present invention, compared to the case where the present configuration is not provided, the supplied release agent is easily developed on the intermediate transfer body, and it is prevented that a release agent non-supply area is formed. Even when hydrophilic ink receiving particles are used, there is an effect that images can be continuously formed while preventing image disturbance and bleeding.

According to the invention of claim 4 , even when using hydrophilic ink-receptive particles having high adhesiveness compared to the case without this configuration, images can be continuously formed while preventing image disturbance. There are effects such as.

  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. FIG. 2 is a configuration diagram illustrating a main part of the recording apparatus according to the first embodiment. FIG. 3 is a configuration diagram illustrating the ink receiving particle layer according to the first embodiment. In the following first embodiment, a case is described in which composite particles are applied as ink receiving particles described later.

  As shown in FIG. 1, the recording apparatus 10 according to the first embodiment includes, for example, an endless belt-shaped intermediate transfer body 12, a charging device 28 that charges the surface of the intermediate transfer body 12, and a charge on the intermediate transfer body 12. A particle supply device 18 for supplying ink-receptive particles 16 to the region to form a particle layer, an ink jet recording head 20 for discharging ink droplets on the particle layer to form an image, and a recording medium 8 superimposed on the intermediate transfer body 12; The image forming apparatus includes a transfer fixing device 22 that transfers and fixes the ink receiving particle layer on the recording medium 8 by applying pressure and heat. An ink receiving particle storage cartridge 19 is detachably connected to the particle supply device 18 via a supply pipe 19A.

  On the upstream side of the charging device 28, a release agent supply device 14 that supplies the release agent 14D to form the release layer 14A is disposed.

  The surface of the intermediate transfer body 12 having a charge formed on the surface by the charging device 28 is formed with the ink receiving particles 16 as a layer by the particle supply device 18, and the ink jet recording head 20 for each color, that is, 20K, 20C, is formed on the particle layer. , 20M, and 20Y, ink droplets of each color are ejected to form a color image.

  The particle layer having the color image formed on the surface is transferred to the recording medium 8 together with the color image by a transfer fixing device (transfer fixing roller) 22. Downstream of the transfer fixing device 22, the ink receiving particles 16 remaining on the surface of the intermediate transfer body 12 are removed, and the intermediate transfer body adhering material such as foreign matters other than the particles (such as paper dust of the recording medium 8) is removed. A cleaning device 24 is provided.

  The recording medium 8 to which the color image has been transferred is carried out as it is, and the intermediate transfer body 12 is again charged on the surface by the charging device 28. At this time, the ink receiving particles transferred to the recording medium 8 absorb and hold the ink droplets 20A, so that they can be quickly carried out.

  Further, if necessary, the intermediate transfer body 12 is provided between the cleaning device 24 and the release agent supply device 14 (hereinafter, “between A and B unless otherwise specified”). You may arrange | position the static elimination apparatus 29 for removing the electric charge which remains on the surface.

In the present embodiment, the intermediate transfer body 12 has a 400 μm thick ethylene propylene rubber (EPDM) surface layer formed on a 1 mm thick polyimide film base layer. Here, it is desirable that the surface resistance value is about 10 ¹³ Ω / □ and the volume resistance value is about 10 ¹² Ω · cm (semiconductive).

  The intermediate transfer body 12 is circulated and conveyed, and a release layer 14 </ b> A is first formed on the surface of the intermediate transfer body 12 by the release agent supply device 14. The release agent 14D is supplied to the surface of the intermediate transfer body 12 by the supply roller 14C of the release agent supply device 14, and the layer thickness is defined by the blade 14B.

  At this time, the release agent supply device 14 may be in continuous contact with the intermediate transfer body 12 or may be separated from the intermediate transfer body 12 for the purpose of continuous image formation and printing. .

  The release agent 14D may be supplied to the release agent supply device 14 from an independent liquid supply system (not shown) so that the supply of the release agent 14D is not interrupted.

  Next, by applying a positive charge to the surface of the intermediate transfer body 12 by the charging device 28, the surface of the intermediate transfer body 12 is charged with a positive charge. Here, if the potential of the ink receiving particles 16 to be supplied / adsorbed to the surface of the intermediate transfer body 12 is formed by the electrostatic force generated by the electric field that can be formed between the supply roller 18A of the particle supply device 18 and the surface of the intermediate transfer body 12. Good.

  In this embodiment, the charging device 28 is used to apply a voltage between a driven roll 31 (connected to the ground) disposed between the charging device 28 and the intermediate transfer body 12 to charge the surface of the intermediate transfer body 12. The configuration is to let

In the charging device 28, an elastic layer (foamed urethane resin) in which a conductivity-imparting material is dispersed is formed on a rod-shaped outer peripheral surface made of stainless steel, and the volume resistivity is adjusted to about 10 ⁶ to 10 ⁸ Ω · cm. A roll-shaped member is used. Further, the surface of the elastic layer is covered with a water / oil repellent coating layer (for example, composed of tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA)) having a thickness of 5 to 100 μm.

  A DC power source is connected to the charging device 28, and the driven roll 31 is electrically connected to the frame ground. The charging device 28 is driven while sandwiching the intermediate transfer body 12 with the driven roll 31, and a predetermined potential difference is generated with the grounded driven roll 31 at the pressed position. An electric charge can be given. Here, for example, a voltage of 1 kv is applied to the surface of the intermediate transfer member 12 by the charging device 28 to charge the surface of the intermediate transfer member 12.

  Further, the charging device 28 may be composed of a corotron or the like.

  Next, the ink supply particles 16 are supplied to the surface of the intermediate transfer body 12 by the particle supply device 18 to form the ink reception particle layer 16A. In the particle supply device 18, a supply roller 18 </ b> A is disposed on a portion of the container in which the ink receiving particles 16 are accommodated, facing the intermediate transfer body 12, and a charging blade 18 </ b> B is disposed so as to press the supply roller 18 </ b> A. The charging blade 18B also has a function of regulating the layer thickness of the ink receiving particles 16 supplied to the surface of the supply roller 18A.

  The ink receiving particles 16 are supplied to the supply roller 18A (conductive roll), the ink receiving particle layer 16A is regulated by the charging blade 18B (conductive blade), and the negative polarity is opposite to the charge on the surface of the intermediate transfer body 12. Is charged. The supply roller 18A can be a solid aluminum roll, and the charging blade 18B can be a metal plate (such as SUS) on which urethane rubber is caught to apply pressure. The charging blade 18B is in contact with the supply roller 18A by a doctor method.

  The charged ink receiving particles 16 form, for example, one particle layer on the surface of the supply roller 18A, and are conveyed to a portion facing the surface of the intermediate transfer body 12, and when close to this, the surfaces of the supply roller 18A and the intermediate transfer body 12 are conveyed. The charged ink receiving particles 16 are moved to the surface of the intermediate transfer member 12 by electrostatic force due to the electric field formed by the potential difference between them.

  At this time, the moving speed of the intermediate transfer body 12 and the rotation speed of the supply roller 18A are relatively set so that a single particle layer is formed on the surface of the intermediate transfer body 12 (peripheral speed ratio). This peripheral speed ratio depends on other parameters such as the charge amount of the intermediate transfer member 12, the charge amount of the ink receiving particles 16, the positional relationship between the supply roller 18A and the intermediate transfer member 12, and the like.

The number of particles supplied onto the intermediate transfer body 12 is increased by relatively increasing the peripheral speed of the supply roller 18A on the basis of the peripheral speed ratio for forming the one ink receptive particle layer 16A. Can be made. When the transferred image density is low (the amount of ink shot is small (for example, 0.1 to 1.5 g / m ² )), the layer thickness is set to the minimum necessary thickness (for example, 1 to 5 μm). When the image density is high (the ink shot amount is large (for example, 4 to 15 g / m ² )), a sufficient layer thickness (for example, 10 to 25 μm) that can hold the ink liquid component (solvent or dispersion medium) It is desirable to control so that it becomes.

  For example, in the case of a character image or the like with a small amount of ink shot, when image formation is performed on one ink receptive particle layer on the intermediate transfer body, the image forming material (pigment) in the ink is on the intermediate transfer body The ink receptive particle layer is trapped on the surface of the ink receptive particle layer, and is fixed to the ink receptive particle surface or the inner particle gap so that the distribution in the depth direction decreases.

  For example, when it is desired to provide the particle layer 16C as the protective layer on the image layer 16B as the final image, the ink receiving particle layer 16A has a thickness of about three layers, and the uppermost layer is imaged with ink. For example (see FIG. 3A), two particle layers C on which image formation is not performed become a protective layer after transfer and fixation, and are formed on the image layer 16B (see FIG. 3B).

  Alternatively, in the case of forming an image with a high ink ejection amount, such as a secondary color or tertiary color image, the ink receptive particle layer can hold an ink liquid component (solvent or dispersion medium) and a recording material (for example, Ink-receptive particles 16 are laminated so that a sufficient number of particles can be captured and not reach the lowermost layer. In this case, the image forming material (pigment) may not be exposed on the surface of the image layer after transfer and fixing, and the ink receiving particles 16 that do not perform image formation may be formed on the image surface as a protective layer.

  Next, the ink jet recording head 20 applies ink droplets 20A to the ink receiving particle layer 16A. The ink jet recording head 20 applies ink droplets 20A to predetermined positions based on predetermined image information.

  Finally, the recording medium 8 and the intermediate transfer body 12 are sandwiched by the transfer fixing device 22, and pressure and heat are applied to the ink receiving particle layer 16A, whereby the ink receiving particle layer 16A is transferred onto the recording medium 8. .

  The transfer fixing device 22 includes a heating roll 22A containing a heating source and a pressure roll 22B facing each other with the intermediate transfer body 12 interposed therebetween. The heating roll 22A and the pressure roll 22B are in contact with each other to form a contact portion. As the heating roll 22A and the pressure roll 22B, a product in which the outer surface of the aluminum core is coated with silicone rubber and further coated with a PFA tube can be used.

  Since the ink receiving particle layer 16A is heated by the heater and pressure is applied at the contact portion between the heating roll 22A and the pressure roll 22B, the ink receiving particle layer 16A is transferred and fixed to the recording medium 8.

  At this time, the organic resin particles constituting the ink receptive particles 16 in the non-image area were softened (or melted) by being heated to a glass transition temperature Tg) or higher, and formed on the surface of the intermediate transfer body 12 by pressure. The ink receiving particle layer 16 </ b> A is released from the release layer 14 </ b> A, and is transferred and fixed onto the recording medium 8. Then, the ink receiving particle layer 16 </ b> A is released from the release layer 14 </ b> A formed on the surface of the intermediate transfer body 12 by pressure, and is transferred onto the recording medium 8. At this time, the transfer fixing property is improved by heating. In this embodiment, the surface of the heating roll 22A is controlled at 160 ° C. At this time, the ink liquid component (solvent or dispersion medium) held in the ink receiving particle layer 16A is held and fixed in the ink receiving particle layer 16A as it is after the transfer. Further, the intermediate transfer body 12 may be preheated before the transfer fixing device 22.

  In addition, as the recording medium 8, a permeation medium (for example, plain paper, ink jet coated paper, etc.) and a non-penetration medium (for example, art paper, resin film, etc.) can be applied. The recording medium is not limited to these, and includes industrial products such as semiconductor substrates.

  Hereinafter, the image forming process of the recording apparatus according to the embodiment will be described in more detail. In the recording apparatus according to the present embodiment, as shown in FIG. 2, the release layer 14 </ b> A can be formed on the surface of the intermediate transfer body 12 by the release layer supply device 14. If the material of the intermediate transfer body 12 is aluminum or PET base, it is particularly desirable to form the release layer 14A. Alternatively, a fluororesin / silicone rubber-based material may be used so that the surface of the intermediate transfer body 12 has releasability.

  Next, the surface of the intermediate transfer member 12 is charged to a polarity opposite to that of the ink receiving particles 16 by the charging device 28. Thereby, the ink receiving particles 16 supplied by the supply roller 18 </ b> A of the particle supply device 18 can be electrostatically adsorbed to form a layer of the ink receiving particles 16 on the surface of the intermediate transfer body 12.

  Next, the ink receiving particles 16 are formed as a layer on the surface of the intermediate transfer body 12 by the supply roller 18 </ b> A of the particle supply device 18. For example, the formed ink receiving particle layer 16A is formed to have a thickness in which the ink receiving particles 16 are overlapped by about three layers. That is, the thickness of the ink receiving particle layer 16A transferred to the recording medium 8 is controlled by controlling the ink receiving particle layer 16A to a desired thickness by the gap between the charging blade 18B and the supply roller 18A as described above. To do. Alternatively, it may be controlled by the peripheral speed ratio between the supply roller 18 </ b> A and the intermediate transfer body 12.

  On the formed ink receiving particle layer 16A, ink droplets 20A are ejected by the ink jet recording head 20 of each color driven by piezoelectric (piezo), thermal, or the like, and an image layer 16B is formed on the ink receiving particle layer 16A. It is formed. The ink droplets 20A ejected from the ink jet recording head 20 are driven into the ink receiving particle layer 16A, and the liquid component of the ink is quickly absorbed into the gaps between the ink receiving particles 16 and the gaps forming the ink receiving particles 16. At the same time, the recording material (for example, pigment) is also captured on the surface of the ink receiving particles 16 (constituting particles) or in the gaps between the particles forming the ink receiving particles 16.

  At this time, the ink liquid component (solvent or dispersion medium) contained in the ink droplet 20A penetrates into the ink receiving particle layer 16A, but the recording material such as pigment is captured on the surface of the ink receiving particle layer 16A or between the particles. The That is, the ink liquid component (solvent or dispersion medium) may penetrate to the back surface of the ink receiving particle layer 16A, but the recording material such as a pigment does not penetrate the back surface of the ink receiving particle layer 16A. Thereby, when the recording material 8 is transferred to the recording medium 8, the particle layer 16C into which the recording material such as the pigment does not penetrate forms a layer on the image layer 16B, so that the particle layer 16C encloses the surface of the image layer 16B. It becomes a protective layer, and an image in which a recording material (for example, a color material such as a pigment) is not exposed on the surface can be formed.

  Next, a color image is formed on the recording medium 8 by transferring / fixing the ink receiving particle layer 16A on which the image layer 16B is formed from the intermediate transfer body 12 onto the recording medium 8. The ink receiving particle layer 16 </ b> A on the intermediate transfer body 12 is heated and pressed by a transfer fixing device (transfer fixing roller) 22 heated by a heating means such as a heater and transferred onto the recording medium 8.

  At this time, the glossiness may be controlled by adjusting the unevenness of the image surface by adjusting heating and pressurization as described later. Further, the glossiness may be controlled by performing cooling peeling.

  Residual particles 16D remaining on the surface of the intermediate transfer member 12 after the ink receptive particle layer 16A has been separated are collected by the cleaning device 24 (see FIG. 1), and the surface of the intermediate transfer member 12 is charged again by the charging device 28. Then, the ink receiving particles 16 are supplied to form the ink receiving particle layer 16A.

  Here, FIG. 3 shows a particle layer used for image formation according to the present invention. As shown in FIG. 3A, a release layer 14 </ b> A is formed on the surface of the intermediate transfer body 12.

  Next, the ink receiving particles 16 are formed as a layer on the surface of the intermediate transfer body 12 by the particle supply device 18. The ink receptive particle layer 16A formed as described above preferably has a thickness in which the ink receptive particles 16 are overlapped by about three layers. The thickness of the ink receiving particle layer 16A transferred to the recording medium 8 is controlled by controlling the ink receiving particle layer 16A to a desired thickness. At this time, the surface of the ink receiving particle layer 16A is leveled so as not to hinder the image formation (formation of the image layer 16B) by the ejection of the ink droplet 20A.

  Further, the recording material such as pigment contained in the ejected ink droplet 20A penetrates to about 1/3 to half of the ink receiving particle layer 16A as shown in FIG. A particle layer 16C that is not infiltrated with the material remains.

  The ink receiving particle layer 16A formed on the recording medium 8 by heating and pressure transfer by the transfer fixing device (transfer fixing roller) 22 is a particle layer not containing ink on the image layer 16B as shown in FIG. 3B. Since 16C exists, the image layer 16B does not appear directly on the surface and functions as a kind of protective layer. For this reason, at least the ink receiving particles 16 after fixing must be transparent.

  Since the particle layer 16C is heated and pressed by the transfer fixing device (transfer fixing roller) 22, the surface can be flattened, and the glossiness of the image surface can be controlled by heating and pressing.

  Further, drying of the ink liquid component (solvent or dispersion medium) trapped inside the ink receiving particles 16 by heating may be promoted.

  The ink liquid component (solvent or dispersion medium) received / held in the ink receiving particle layer 16A is held in the ink receiving particle layer 16A even after transfer fixing, and is removed by natural drying.

  Through the above steps, image formation is completed. With respect to the intermediate transfer body 12, there are foreign particles such as residual particles 16 </ b> D remaining on the intermediate transfer body 12 after the ink receiving particles 16 are transferred to the recording medium 8, or paper dust released from the recording medium 8. May be removed by the cleaning device 24.

  Further, a static elimination device 29 may be arranged downstream of the cleaning device 24. For example, a conductive roll is used as the static elimination device 29 and is sandwiched between the driven roll 31 (ground) and a voltage of about ± 3 kV and 500 Hz is applied to the surface of the intermediate transfer body 12 to neutralize the surface of the intermediate transfer body 12. .

  Various other device conditions such as the above-mentioned charging voltage, particle layer thickness, fixing temperature, etc. are optimized because the optimum conditions are determined by the ink receiving particles 16 or ink composition, ink discharge amount, etc. To do.

<Each component>
Next, components of each step of the embodiment will be described in detail.

<Intermediate transfer member>
The intermediate transfer body 12 on which the ink receptive particle layer is formed may be a belt shape or a cylindrical shape (drum shape) as in the embodiment. In order to supply and hold the ink receiving particles on the surface of the intermediate transfer member by electrostatic force, the outer peripheral surface of the intermediate transfer member needs to have a semiconductive or insulating particle holding property. As the electrical characteristics of the surface of the intermediate transfer member, the surface resistivity is 10 ¹⁰ to 10 ¹⁴ Ω / □ in the case of semiconductivity, the volume resistivity is 10 ⁹ to 10 ¹³ Ω · cm, and the surface resistance in the case of insulation. A member having a rate of 10 ¹⁴ Ω / □ and a volume resistivity of 10 ¹³ Ω · cm or more is used.

  In the case of a belt shape, the base material can be driven by a belt in the apparatus, has the required mechanical strength, and particularly has the required heat resistance when using heat during transfer / fixing. Good. Specifically, polyimide, polyamideimide, aramid resin, polyethylene terephthalate, polyester, polyethersulfone, stainless steel and the like are used.

  In the case of a drum shape, aluminum, stainless steel, etc. can be considered as the base material.

  In order to exhibit a heating method by electromagnetic induction in the fixing process in the transfer fixing device (transfer fixing roller) 22, a heat generating layer may be formed on the intermediate transfer body 12 instead of the transfer fixing device (transfer fixing roller) 22. Good. A metal that generates electromagnetic induction is used for the heat generating layer. For example, nickel, iron, copper, aluminum, chromium, or the like can be selected.

<Particle supply process>
An ink receiving particle layer 16A is formed on the surface of the intermediate transfer body 12 on which the release layer 14A is formed. At this time, as a method of forming the ink receptive particle layer 16A, a method of supplying a general electrophotographic toner to the photoreceptor can be applied. That is, charges are previously supplied to the surface of the intermediate transfer body 12 by a general electrophotographic charging method (charging by the charging device 28, etc.). The ink receiving particles 16 are triboelectrically charged (one-component triboelectric charging method or two-component method) with a polarity opposite to the charge on the surface of the intermediate transfer member 12.

  The ink receiving particles 16 held on the supply roller 18A form an electric field with the surface of the intermediate transfer member 12, and are moved / supplied onto the intermediate transfer member 12 by electrostatic force and held. At this time, the thickness of the ink receptive particle layer 16A may be controlled by the thickness of the image layer 16B formed on the ink receptive particle layer 16A (in accordance with the amount of ink to be applied). At this time, the absolute value of the charge amount of the ink receiving particles 16 is preferably in the range of 5 μc / g to 50 μc / g.

  Here, the thickness of the ink receiving particle layer 16A is desirably 1 μm to 100 μm, more desirably 1 μm to 50 μm, and further desirably 5 μm to 25 μm. In addition, the porosity in the ink receiving particle layer (that is, the void ratio between the ink receiving particles + the void ratio in the ink receiving particles (trap structure)) is desirably 10% to 80%, and more desirably. It is 30 to 70%, more desirably 40% to 60%.

  Hereinafter, a particle supply process corresponding to a one-component supply (development) method will be described.

  The ink receiving particles 16 are supplied to the supply roller 18A, and the thickness of the particle layer is regulated and charged by the charging blade 18B.

  The charging blade 18B functions to regulate the layer thickness of the ink receiving particles 16 on the surface of the supply roller 18A. For example, the layer thickness of the ink receiving particles 16 on the surface of the supply roller 18A is changed by changing the pressure applied to the supply roller 18A. To change. For example, the thickness of the ink receiving particles 16 on the surface of the supply roller 18A is, for example, one layer, and the thickness of the ink receiving particles 16 formed on the surface of the intermediate transfer body 12 is approximately one layer. Further, the pressing force of the charging blade 18B is controlled to be low, the thickness of the ink receiving particles 16 formed on the surface of the supply roller 18A is increased, and the thickness of the ink receiving particles formed on the surface of the intermediate transfer member 12 is increased. It may be increased.

  As another method, when the peripheral speed of the supply roller 18A for forming one particle layer on the surface of the intermediate transfer body 12 and the intermediate transfer body 12 is set to 1, the peripheral speed of the supply roller 18A is increased and the intermediate transfer is performed. It can be controlled to increase the number of ink receptive particles 16 supplied on the body 12 and increase the thickness of the ink receptive particle layer on the intermediate transfer body 12. It is also possible to control by combining the above methods. In the above configuration, for example, the ink receiving particles 16 are negatively charged, and the surface of the intermediate transfer body 12 is positively charged.

  By controlling the layer thickness of the ink receiving particle layer in this way, it is possible to form a pattern whose surface is covered with a protective layer while suppressing consumption of the ink receiving particle layer.

As a charging roll in the charging device 28, an elastic layer in which a conductivity imparting material is dispersed is formed on the outer peripheral surface of a rod-like or pipe-like member made of aluminum, stainless steel, or the like, and a volume resistivity of 10 ⁶ to 10 ⁸ Ω · A roll of φ10 to 25 mm adjusted to about cm can be used.

  The elastic layer is made of a resin material such as urethane resin, thermoplastic elastomer, epichlorohydrin rubber, ethylene-propylene-diene copolymer rubber, silicone rubber, acrylonitrile-butadiene copolymer rubber, or polynorbornene rubber. A preferred material used in the above mixture is urethane foam resin.

  As the foamed urethane resin, a resin obtained by mixing and dispersing a hollow body such as a hollow glass bead or a thermal expansion type microcapsule in a urethane resin to provide a closed cell structure is desirable.

  Further, the surface of the elastic layer may be covered with a water-repellent coating layer having a thickness of 5 to 100 μm.

  A DC power source is connected to the charging device 28, and the driven roll 31 is electrically connected to the frame ground. The charging device 28 is driven while the intermediate transfer body 12 is sandwiched between the charging roll 31 and a predetermined potential difference is generated between the charging apparatus 28 and the grounded driven roll 31 at the pressing position.

<Marking process>
Based on the image signal, ink droplets 20A are ejected from the ink jet recording head 20 to the layer of ink receptive particles 16 (ink receptive particle layer 16A) formed on the surface of the intermediate transfer body 12, thereby forming an image. The ink droplets 20A ejected from the ink jet recording head 20 are driven into the ink receiving particle layer 16A, and the ink droplets 20A are quickly absorbed by the interparticle gaps (voids) formed in the ink receiving particles 16 to be recorded. The material (for example, pigment) is trapped in the surface of the ink receiving particle 16 or the interparticle gap constituting the ink receiving particle 16.

  In this case, it is desirable to capture (trap) many recording materials (for example, pigments) on the surface of the ink receiving particle layer 16A. The interparticle gaps (voids) in the ink receiving particles 16 exhibit a filter effect, trap recording material (for example, pigment) on the surface of the ink receiving particle layer 16A, and the interparticle gaps in the ink receiving particles 16. It is expressed by being trapped and fixed in

  In order to ensure that the recording material (for example, pigment) is trapped in the surface of the ink receiving particle layer 16A and the inter-particle gap in the ink receiving particle 16, the ink and the ink receiving particles 16 are reacted to form a recording material ( For example, a method of quickly insolubilizing (aggregating) the pigment) may be employed. Specifically, it is possible to apply a reaction between the ink and the polyvalent metal salt or a pH reaction type as the reaction.

  In addition, a line type ink jet recording head having a width equal to or larger than the width of the recording medium is desirable. However, using a conventional scan type ink jet recording head, images are sequentially formed on the particle layer formed on the intermediate transfer member. It may be formed. The ink discharge means of the inkjet recording head 20 is not limited as long as it is a means capable of discharging ink, such as a piezoelectric element drive type and a heating element drive type. As the ink itself, an ink using a conventional dye as a coloring material can be used, but a pigment ink is desirable.

  When the ink receiving particles 16 are reacted with the ink, the treatment is performed with an aqueous solution containing an aggregating agent (for example, a polyvalent metal salt or an organic acid) that gives the effect of aggregating the pigment by reacting the ink receiving particles 16 with the ink. Use and dry.

<Transfer process>
The ink receiving particle layer 16 </ b> A that receives the ink droplet 20 </ b> A and has an image formed thereon is transferred and fixed to the recording medium 8, thereby forming an image on the recording medium 8. The transfer and fixing may be performed by different processes, but it is desirable that the transfer and fixing be performed substantially simultaneously. Fixing includes either a method of heating or pressurizing the ink receptive particle layer 16A, or a method of using both heating and pressurization, and a method of performing heating / pressing substantially simultaneously is desirable.

  Further, by controlling the heating / pressurization, it is possible to control the surface physical properties of the ink receiving particle layer 16A and to control the gloss (glossiness). Further, when the recording medium 8 onto which the image (ink-receptive particle layer 16A) has been transferred after being heated / pressurized is peeled off from the intermediate transfer body 12, the ink-receptive particle layer 16A may be peeled off after being cooled. Good. The cooling method may be forced cooling such as natural cooling or air cooling. For these processes, the intermediate transfer member 12 preferably has a belt shape.

  The ink image is formed on the surface layer of the ink receiving particle 16 layer formed on the intermediate transfer body 12 (the recording material (pigment) is trapped on the surface of the ink receiving particle layer 16A) and transferred to the recording medium 8. By doing so, the ink image is preferably formed so as to be protected by the particle layer 16 </ b> C of the ink receiving particles 16.

  The ink liquid component (solvent or dispersion medium) received / held in the ink receiving particle 16 layer is held in the ink receiving particle 16 layer even after the transfer and fixing, and is removed by natural drying.

<Release layer>
The release agent supply device 14 forms a release layer 14 </ b> A of the release agent 14 </ b> D on the surface of the intermediate transfer body 12 before supplying the ink receiving particles 16.

  The method for supplying the release layer 14A includes a release agent 14D, a release agent 14D supplied to the release agent supply member, and the release member 14D supplied to the surface of the intermediate transfer body 12 by the supply member. A method of forming the layer 14A, a method of forming the release layer 14A on the surface of the intermediate transfer body 12 by a supply member impregnated with the release agent 14D, and the like are used.

Here, the release agent 14D includes at least one selected from silicone oil, fluorine oil, and an organic compound having a solubility parameter (SP value) of 11 or less.
However, as the release agent 14D in the present embodiment, an organic compound having a solubility parameter (SP value) of 8 to 11 is used.

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.

  An organic compound having a solubility parameter (SP value) of 11 or less desirably has a solubility parameter (SP value) of 10 or less, more desirably a solubility parameter (SP value) of 8 to 10. By setting the solubility parameter (SP value) within the above range, it becomes difficult for the ink receiving particles 16 to adhere firmly to the intermediate transfer body 12.

The solubility parameter (SP value) is a value calculated by the following formula of Fedors calculated from the evaporation energy (Δei) and the molar volume (Δvi) of atoms or atomic groups having a chemical structure.
Formula: [SP value = (ΣΔei / ΣΔvi) ^1/2 ]

Examples of organic compounds having a solubility parameter (SP value) in the above range include polyalkylene glycols and surfactants.
Examples of the polyalkylene glycol include polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide copolymer, and polybutylene glycol. Among these, polypropylene glycol is desirable.
Examples of the surfactant include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant. Among these, a nonionic surfactant is desirable.

Examples of the anionic surfactant include alkylbenzene sulfonate, alkylphenyl sulfonate, alkyl naphthalene sulfonate, higher fatty acid salt, sulfate of higher fatty acid ester, sulfonate of higher fatty acid ester, and higher alcohol ether. Sulfate and sulfonates, higher alkyl sulfosuccinates, higher alkyl phosphate esters, phosphate esters of higher alcohol ethylene oxide adducts, fatty acid metal soaps, N-acyl amino acids and their salts, alkyl ether carboxylates , Acylated peptide, formalin polycondensate of naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfoacetate, α-olefin sulfonate, N-acyl methyl taurine, sulfated oil, alkyl ether sulfate, Secondary higher alcohol ethoxy sulfates, polyoxyethylene alkylphenyl ether sulfates, sulfates of fatty alkylol amide, alkyl ether phosphoric acid ester salts, alkyl phosphoric acid ester salts.
Examples of the cationic surfactant include aliphatic amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium and the like.
Examples of amphoteric surfactants include carboxybetaine, aminocarboxylate, imidazolinium betaine, and lecithin.
Nonionic surfactants include polyoxyethylene alkyl ether, single chain length polyoxyethylene alkyl ether, polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative , Ethylene oxide derivatives of alkylphenol formalin condensate, polyoxyethylene-polyoxypropylene copolymer (polyoxyethylene polyoxypropylene block polymer), polyoxyethylene polyoxypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene Castor oil and hydrogenated castor oil, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbitol fatty acid ester, Examples include reethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, fatty acid alkanolamide, polyoxyethylene fatty acid amide, polyoxyethylene alkylamide, alkylamine oxide and the like. Among these, polyoxyethylene alkyl ether and polyoxyethylene-polyoxypropylene copolymer are preferable.

  The viscosity of the release agent 14D is preferably, for example, 5 to 200 mPa · s, more preferably 5 to 100 mPa · s, and further preferably 5 to 50 mPa · s.

The viscosity is measured as follows. The viscosity of the ink obtained was measured using Rheomatt 115 (manufactured by Contraves) as a measuring device. The measurement was performed by placing the sample in a measurement container and mounting it on the apparatus by a predetermined method, under the conditions of a measurement temperature of 40 ° C. and a shear rate of 1400 s ⁻¹ .

  The surface tension of the release agent 14D is, for example, in the range of 40 mN / m or less (desirably 30 mN / m or less, more desirably 25 mN / m or less).

  The surface tension is measured as follows. In an environment of 23 ± 0.5 ° C. and 55 ± 5% RH, the surface tension of the obtained sample was measured using a Wilhelmy type surface tension meter (manufactured by Kyowa Interface Science Co., Ltd.).

  The boiling point of the release agent 14D is, for example, in the range of 250 ° C. or higher (preferably 300 ° C. or higher, more preferably 350 ° C. or higher) under 760 mmHg.

  The boiling point is measured as follows. Measurement was performed according to JIS K2254, and the initial boiling point was used as the boiling point.

  The difference between the solubility parameter (SP value) of the release agent 14D and the solubility parameter (SP value) of the material constituting the surface of the intermediate transfer member is, for example, 2 or less (preferably 1 or less, more preferably 0.2 to 0). .8).

  The contact angle of the release agent 14D with respect to the surface of the intermediate transfer member (its constituent material) is, for example, in the range of 40 deg or less (desirably 30 deg or less, more desirably 5 to 25 deg).

  In addition, the measuring method of a contact angle is performed as follows. This was performed by dropping a predetermined amount of the sample onto the object to be dropped using a FIBRO 1100 DAT MK II (manufactured by FIBRO system) apparatus. Specifically, 4.0 μl of the sample was set on the object to be dropped, and the contact angle at the time when 0.04 seconds had elapsed after the sample was dropped on the object to be dropped was measured. In addition, when the contact angle could not be measured when 0.04 seconds had elapsed after the sample was dropped, the contact angle measured when the sample could be measured after the sample was dropped was used.

  The layer thickness of the release layer 14A by the release agent 14D is, for example, in the range of 1 μm or less (desirably 0.5 μm or less, more desirably 0.1 μm or less).

<Cleaning process>
In order to refresh the surface of the intermediate transfer body 12 to enable repeated use, a process of cleaning the surface with the cleaning device 24 is necessary. The cleaning device 24 includes a cleaning unit and a particle transport / recovery unit (not shown). By the cleaning described above, the ink receiving particles 16 (residual particles 16D) remaining on the surface of the intermediate transfer body 12 are removed, and other than particles. The adhering matter adhering to the surface of the intermediate transfer body 12 such as the foreign matter (paper dust of the recording medium 8) is removed. The recovered residual particles 16D may be reused.

<Static removal process>
Before forming the release layer 14 </ b> A, the surface of the intermediate transfer body 12 may be neutralized using the neutralization device 29.

  In the recording apparatus according to the embodiment described above, after the release agent 14D is supplied to the surface of the intermediate transfer body 12 by the release agent supply apparatus 14 to form the release layer 14A, the surface of the intermediate transfer body is covered by the charging device 28. Charge. Next, the ink receiving particles 16 are supplied from the particle supply device 18 to the region where the release layer of the intermediate transfer body 12 is formed and charged, thereby forming a particle layer. Next, an ink droplet is ejected onto the particle layer by the ink jet recording head 20 to form an image. As a result, ink is received by the ink receiving particles 16. Next, the recording medium 8 is overlapped with the intermediate transfer body 12, and pressure and heat are applied by the transfer fixing device 22 to transfer and fix the ink receiving particle layer on the recording medium 8.

  Then, by applying the specific release agent as the release agent 14D, it is possible to suppress the ink-receiving particles 16 having hydrophilicity having a configuration described later from being firmly attached to the intermediate transfer body 12.

  Hereinafter, the ink receiving particles applied in the above embodiment will be described in detail. In the following description, the reference numerals are omitted.

  The ink receptive particles are those that receive ink components when the ink comes into contact with the particles. Here, the ink receptivity indicates holding at least a part (at least a liquid component) of the ink component. The ink receiving particles include at least an organic resin having a polar monomer ratio of 10 mol% to 90 mol% with respect to all monomer components. Specifically, the ink receiving particles include, for example, a configuration having particles configured to contain the organic resin (hereinafter referred to as hydrophilic organic particles) (hereinafter including the hydrophilic organic particles). Are called “mother particles”).

  Here, the ink-receptive particles being hydrophilic means that at least an organic resin having a ratio of polar monomers to all monomer components of 10 mol% or more and 90 mol% or less is included. Such ink receptive particles have a property of being more sticky than hydrophobic.

  The ink receptive particles may have a form in which the mother particles are composed of particles (primary particles) of hydrophilic organic particles alone, or a form in which the mother particles are composed of composite particles in which at least hydrophilic organic particles are aggregated. Good.

  Here, in the case where the mother particles are composed of single particles (primary particles) of hydrophilic organic particles, when the ink receiving particles receive the ink, if the ink adheres to the ink receiving particles, at least the liquid component of the ink The ink liquid component is absorbed by the hydrophilic organic particles.

  In this way, the ink receiving particles receive ink. Then, recording is performed by transferring the ink receiving particles that have received the ink to a recording medium.

  On the other hand, in the case where the mother particles are composed of composite particles in which at least hydrophilic organic particles are aggregated, when the ink receiving particles receive ink, first, when the ink adheres to the ink receiving particles, at least the liquid of the ink The component is captured (trapped) by a gap between particles (at least hydrophilic organic particles) constituting the composite particle (hereinafter, the interparticle gap (void) may be referred to as a trap structure). At this time, among the ink components, the recording material is attached to the surface of the ink receiving particles or trapped by the trap structure. In this way, the ink receiving particles receive ink. Then, recording is performed by transferring the ink receiving particles that have received the ink to a recording medium.

  The trapping (trapping) of the ink liquid component by the trap structure is a physical and / or chemical trapping by a gap between particles (physical particle wall structure).

Then, by applying a configuration in which the mother particles are composed of composite particles in which at least hydrophilic organic particles are aggregated, trapping by traps (physical particle wall structure) between the particles constituting the composite particles is applied. In addition, the ink liquid component is absorbed and held by the hydrophilic organic particles.
Ink liquid components are also absorbed and retained by hydrophilic organic particles.

  Further, after the transfer of the ink receiving particles, the components of the hydrophilic organic particles constituting the ink receiving particles also function as a binder resin or a coating resin for the recording material contained in the ink. Further, when the ink receiving particles are composite particles, the recording material is trapped in the trap structure. In particular, it is desirable to apply a transparent resin as a component of the hydrophilic organic particles constituting the ink receiving particles.

  In addition, in order to improve the fixability (rubbing resistance) of an ink (for example, pigment ink) using an insoluble component such as a pigment or a dispersed particulate material as a recording material, it is necessary to add a large amount of resin to the ink. If a large amount of polymer is added to the processing liquid (including the treatment liquid), the reliability such as nozzle clogging of the ink discharge means is deteriorated. On the other hand, in the above configuration, the organic resin component constituting the ink receiving particles can also function as the resin.

  Here, the “gap between particles constituting the composite particle”, that is, “trap structure” is a physical particle wall structure capable of capturing at least a liquid. The size of the gap is preferably 0.1 to 5 [mu] m, more preferably 0.3 to 1 [mu] m in terms of the maximum aperture. In particular, the size of the gap is preferably a size that can trap a recording material, particularly, for example, a pigment having a volume average particle diameter of 100 nm. Micropores having a maximum opening diameter of less than 50 nm may exist. Moreover, it is good for the space | gap and the capillary tube to have communicated inside the particle | grains.

  The size of this gap is determined as follows. It can be obtained by reading a scanning electron microscope (SEM) image of the particle surface with an image analyzer, detecting the gap by binarization processing, and analyzing the size and distribution of the gap.

  As described above, the trap structure preferably traps not only the liquid component of the ink components but also the recording material. When a recording material, particularly a pigment, is trapped (trapped) together with the ink liquid component in the trap structure, the recording material is held and fixed without being unevenly distributed inside the ink receiving particles. The liquid component of the ink is mainly an ink solvent or a dispersion medium (vehicle liquid).

  Hereinafter, the ink receiving particles will be described in more detail. The ink receptive particles may have a form in which the mother particles are composed of single particles (primary particles) of hydrophilic organic particles as described above, and the mother particles are composed of composite particles in which at least hydrophilic organic particles are aggregated. There may be a form. Examples of particles other than the hydrophilic organic particles constituting the composite particles include inorganic particles and porous particles. Of course, the mother particle may be composed of composite particles in which only a plurality of hydrophilic organic particles are aggregated. In addition to the hydrophobic organic particles, for example, inorganic particles may be used as the particles to be attached to the surface of the mother particles.

  As specific configurations of the ink receiving particles, for example, as shown in FIG. 4, mother particles 101 composed of particles (primary particles) of hydrophilic organic particles 101 </ b> A alone, and inorganic particles attached to the mother particles 101. 102, and the form of the ink receiving particles 100 having the same. In addition, as shown in FIG. 5, an ink receptivity having base particles 101 of composite particles in which hydrophilic organic particles 101 </ b> A and inorganic particles 101 </ b> B are combined, and inorganic particles 102 attached to the base particles 101. The form of the particle | grains 110 is also mentioned. Note that a void structure is formed in the mother particle of the composite particle by the gap between the particles.

  Here, when the mother particle is composed of composite particles, the mass ratio of hydrophilic organic particles to other particles (hydrophilic organic particles: other particles) is, for example, 5 when other particles are inorganic particles. : It is mentioned that it is the range of 1-1: 10.

  In addition, the particle diameter of the mother particles may be in the range of, for example, 0.1 to 50 μm (desirably 0.5 μm to 25 μm, more desirably 1 μm to 10 μm) in terms of a sphere equivalent average particle diameter.

In the case of constituting the matrix particles are composite particles, include that the BET specific surface area _{(N 2)} is in the range of, for example, 1~750m ² / g.

  When the mother particles are composed of composite particles, the composite particles are obtained, for example, by granulating the particles in a semi-sintered state. The semi-sintered state refers to a state in which a certain amount of particle shape remains and voids are retained between the particles. When the ink liquid component is trapped in the trap structure, at least a part of the particles may be dissociated, that is, the composite particles may be disassembled and the particles constituting the particles may be dispersed.

  Next, the hydrophilic organic particles will be described. In the hydrophilic organic particles, for example, the ratio of the polar monomer to the total monomer component is 10 mol% or more and 90 mol% or less, desirably 15 mol% or more and 85 mol% or less, more desirably 30 mol% or more and 80 mol% or less. It is comprised including the organic resin which is. Specifically, the hydrophilic organic particles preferably include an organic resin having a ratio of the polar monomer (hereinafter referred to as a water-absorbing resin).

  Here, the polar monomer is a monomer containing an ethylene oxide group, a carboxylic acid, a sulfonic acid, a substituted or unsubstituted amino group, a hydroxyl group, and a salt thereof. For example, in the case of imparting positive chargeability, it is desirable to use a monomer having a chlorination structure such as a (substituted) amino group, a (substituted) pyridine group, an amine salt thereof, or a quaternary ammonium salt. In the case of imparting negative charge, a monomer having an organic acid (salt) structure such as carboxylic acid (salt) or sulfonic acid (salt) is desirable.

  In addition, the ratio of a polar monomer is calculated | required as follows. First, the constitution of the organic component is identified from analysis techniques such as mass spectrometry, NMR, and IR. Then, based on JIS K0070 or JIS K2501, the acid value and base number of an organic component are measured. The ratio of the polar monomer can be calculated from the constitution of the organic component and the acid value / base value. The same applies hereinafter.

  The hydrophilic organic particles are made of, for example, a liquid absorbing resin. The absorbed ink liquid component (for example, water or an aqueous solvent) acts as a plasticizer for the resin (polymer), so it can soften and contribute to fixing properties.

  The liquid absorbing resin is preferably a weak liquid absorbing resin. For example, when absorbing water as a liquid, this weak liquid-absorbing resin absorbs from several percent (≈5%) to several hundred percent (≈500%), preferably about 5% to 100% of the resin mass. It means a lyophilic resin capable of liquid.

  The liquid-absorbing resin can be composed of, for example, a homopolymer of a hydrophilic monomer or a copolymer composed of both a hydrophilic monomer and a hydrophobic monomer. In order to obtain a weak water-absorbing resin, the copolymer is desirable. In addition, not only the monomer but also a graft copolymer or block copolymer in which other units such as a polymer / oligomer structure are copolymerized as a start may be used.

Here, as a hydrophilic monomer, -OH, -EO unit (ethylene oxide group), -COOM (M is alkali metal, such as hydrogen, Na, Li, and K, ammonia, organic amines, etc.). ), - SO ₃ M (M is, for example, hydrogen, Na, Li, alkali metals K, etc., ammonia, organic amines, etc.), - NR ₃ (R is, for example, H, alkyl, phenyl, etc.). - NR ₄ X (R is, for example, H, alkyl, phenyl, etc., and X is, for example, halogen, sulfate radical, acid anions such as carboxylic acid, BF ₄ , etc.) and the like. It is done. Specific examples include 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, acrylamide, acrylic acid, methacrylic acid, unsaturated carboxylic acid, crotonic acid, maleic acid, and the like. Examples of hydrophilic units or monomers include cellulose derivatives such as cellulose, ethyl cellulose, carboxymethyl cellulose, starch derivatives, monosaccharide / polysaccharide derivatives, vinyl sulfonic acid, styrene sulfonic acid, acrylic acid, methacrylic acid, (anhydrous) Polymeric carboxylic acids such as maleic acid, (partially) neutralized salts thereof, vinyl alcohols, vinyl pyrrolidone, vinyl pyridine, derivatives such as amino (meth) acrylate and dimethylamino (meth) acrylate, and oniums thereof Salts, amides such as acrylamide and isopropylacrylamide, polyethylene oxide chain-containing vinyl compounds, hydroxyl group-containing vinyl compounds, polyesters composed of polyfunctional carboxylic acids and polyhydric alcohols, especially trimellitic acid Branched polyester containing a large amount of content and terminal carboxylic acid or hydroxyl functionality more acid as a constituent component, a polyester containing polyethylene glycol structure, etc. may be mentioned.

  Examples of the hydrophobic monomer include monomers having a hydrophobic group. Specifically, for example, olefin (ethylene, butadiene, etc.), styrene, α-methylstyrene, α-ethylstyrene, methyl methacrylate, Examples include ethyl methacrylate, butyl methacrylate, acrylonitrile, vinyl acetate, methyl acrylate, ethyl acrylate, butyl acrylate, and lauryl methacrylate. Hydrophobic units or monomers include styrene derivatives such as styrene, α-methylstyrene, vinyltoluene, vinylcyclohexane, vinylnaphthalene, vinylnaphthalene derivatives, alkyl acrylate esters, phenyl acrylate esters, alkyl methacrylate esters, methacrylic acid Examples thereof include phenyl ester, methacrylic acid cycloalkyl ester, crotonic acid alkyl ester, itaconic acid dialkyl ester, maleic acid dialkyl ester and the like, and derivatives thereof.

  Specific examples of the liquid absorbing resin that is a copolymer of the hydrophilic monomer and the hydrophobic monomer include, for example, (meth) acrylic acid esters, styrene / (meth) acrylic acid / (anhydrous). ) Preferred are maleic acid copolymers, olefin polymers such as ethylene / propylene (or modified products thereof, or carboxylic acid unit introduced products by copolymerization), branched polyesters and polyamides whose acid value has been improved with trimellitic acid, etc. Can be mentioned.

  Examples of the liquid absorbent resin include a neutral salt structure (for example, carboxylic acid). This neutralized salt structure such as carboxylic acid forms an ionomer by interaction with the cation when ink containing a cation (for example, a monovalent metal cation such as Na or Li) is absorbed.

  It is also desirable that the liquid absorbent resin contains a substituted or unsubstituted amino group or a substituted or unsubstituted pyridine group. The group exerts a bactericidal effect and interaction with a recording material having an anionic group (for example, pigment or dye).

  Here, in the liquid absorbent resin, the molar ratio (hydrophilic monomer: hydrophobic monomer) between the hydrophilic unit (hydrophilic monomer) and the hydrophobic unit (hydrophilic monomer) is, for example, 5: 95-70: 30.

  Further, the absorbent resin may be ion-crosslinked with ions supplied from the ink. Specifically, a unit containing a carboxylic acid in the resin such as a copolymer containing a carboxylic acid such as (meth) acrylic acid or maleic acid or a (branched) polyester having a carboxylic acid is present in the water-absorbing resin. Can do. Ionic crosslinking, acid / base interaction, etc. occur between the carboxylic acid in the resin and the alkali metal cation, alkaline earth metal cation, organic amine / onium cation, etc. supplied from the liquid such as water-based ink.

  The common characteristics of the liquid-absorbing resin and the non-liquid-absorbing resin (hereinafter collectively referred to as organic resin) constituting the hydrophobic organic particles will be described.

  The liquid-absorbent resin may have a straight chain structure, but a split structure. Further, the liquid absorbent resin is preferably non-crosslinked or low crosslinked. The liquid-absorbing resin may be a linear random copolymer or block copolymer, but a branched polymer (including a branched random copolymer, block copolymer, and graft copolymer). Can be used more suitably. For example, in the case of polyester synthesized by polycondensation, end groups can be increased in a branched structure. This branched structure is generally synthesized by adding so-called cross-linking agents such as divinylbenzene and di (meth) acrylates during synthesis (for example, adding less than 1%) or adding a large amount of an initiator together with the cross-linking agent. It is one of the practical methods.

The liquid absorbing resin may further contain a charge control agent for electrophotographic toner such as low molecular quaternary ammonium salts, organic borates, and salt-forming compounds of salicylic acid derivatives. The conductivity is controlled by conductivity such as tin oxide or titanium oxide (where conductivity means, for example, a volume resistivity of less than 10 ⁷ Ω · cm. The same applies hereinafter unless otherwise specified.) Addition of an inorganic substance that is semiconductive (here, semiconductive means, for example, a volume resistivity of 10 ⁷ to 10 ¹³ Ωcm. The same applies unless otherwise specified) is effective.

  The liquid absorbent resin is preferably an amorphous resin, and the glass transition temperature (Tg) thereof is, for example, 40 ° C to 90 ° C. The glass transition temperature (and melting point) was determined from the main maximum peak measured according to ASTM D3418-8. DSC-7 manufactured by Perkin Elmer Co. can be used for measurement of the main maximum peak. The temperature correction of the detection part of this apparatus uses the melting point of indium and zinc, and the correction of heat quantity uses the heat of fusion of indium. As the sample, an aluminum pan was used, an empty pan was set as a control, and the measurement was performed at a heating rate of 10 ° C./min.

  As for the weight average molecular weight of liquid absorbing resin, 3000-300,000 are mentioned, for example. The weight average molecular weight is measured under the following conditions. For example, GPC uses “HLC-8120GPC, SC-8020 (manufactured by Tosoh Corporation)” apparatus, and two columns are “TSKgel, SuperHM-H (6.0 mm ID × 15 cm, manufactured by Tosoh Corporation)”. And THF (tetrahydrofuran) was used as the eluent. As experimental conditions, the sample concentration was 0.5%, and the flow rate was 0.6 ml / min. The experiment was conducted using a sample injection amount of 10 μl, a measurement temperature of 40 ° C., and an IR detector. The calibration curve is “polystylen standard sample TSK standard” manufactured by Tosoh Corporation: “A-500”, “F-1”, “F-10”, “F-80”, “F-380”, “A-2500”. ”,“ F-4 ”,“ F-40 ”,“ F-128 ”, and“ F-700 ”.

  As for the acid value of liquid absorbing resin, 50-777 mgKOH / g is mentioned, for example in conversion of a carboxylic acid group (-COOH). The acid value in terms of this carboxylic acid group (—COOH) was measured as follows.

  The acid value was measured according to JIS K0070 and using a neutralization titration method. That is, an appropriate amount of a sample is taken, 100 ml of a solvent (diethyl ether / ethanol mixed solution) and a few drops of an indicator (phenolphthalein solution) are added, and shaken sufficiently until the sample is dissolved on a water bath. This was titrated with a 0.1 mol / l potassium hydroxide ethanol solution, and the end point was when the red color of the indicator lasted for 30 seconds. When the acid value is A, the sample amount is S (g), the 0.1 mol / l potassium hydroxide ethanol solution used for the titration is B (ml), and f is the factor of the 0.1 mol / l potassium hydroxide ethanol solution. , A = (B × f × 5.611) / S.

  The liquid-absorbing resin described above is used with the ratio of the polar monomer being controlled within the above range regardless of the form.

  The particle diameter of the hydrophilic organic particles has a sphere equivalent average particle diameter of, for example, 0.1 to 50 μm (preferably 0.5 μm to 25 μm, more preferably 1 μm to 10 μm) when the primary particles are used as the mother particles. Can be mentioned. On the other hand, when composing the composite particles, for example, a range of 10 nm to 30 μm (desirably 50 nm to 10 μm, more desirably 0.1 μm to 5 μm) in terms of a sphere-converted average particle diameter can be mentioned.

  The ratio of the hydrophilic organic particles to the entire ink receiving particles is, for example, in the range of 75% or more, desirably 85% or more, and more desirably 90 to 99% in terms of mass ratio.

  Next, the inorganic particles constituting the composite particles together with the hydrophilic organic particles and the inorganic particles attached to the mother particles will be described. As the inorganic particles, any of non-porous particles and porous particles can be used. Examples of the inorganic particles include colorless, light-colored or white particles (for example, colloidal silica, alumina, calcium carbonate, zinc oxide, titanium oxide, tin oxide, etc.). These inorganic particles may be subjected to surface treatment (partial hydrophobization treatment, specific functional group introduction treatment, etc.). For example, in the case of silica, the hydroxyl group of silica is treated with a silylating agent such as trimethylchlorosilane or t-butyldimethylchlorosilane to introduce an alkyl group. Hydrochloric acid is generated by the silylating agent, and the reaction proceeds. At this time, if amine is added, hydrochloric acid can be converted into hydrochloride to promote the reaction. It can be controlled by controlling the treatment amount and treatment conditions of a silane coupling agent having an alkyl group or a phenyl group as a hydrophobic group or a coupling agent such as titanate or zirconate. Further, surface treatment with aliphatic alcohols, higher fatty acids and derivatives thereof is also possible. Also, coupling agents having a cationic functional group such as a (substituted) amino group or a silane coupling agent having a quaternary ammonium salt structure, coupling agents having a fluorine-based functional group such as fluorosilane, and other carboxylic acids Surface treatment with a coupling agent having an anionic functional group such as the above is also possible. These inorganic particles may be so-called internally added contained in the hydrophilic organic particles.

  The particle diameter of the inorganic particles constituting the composite particles is, for example, in the range of 10 nm to 30 μm (desirably 50 nm to 10 μm, more desirably 0.1 μm to 5 μm) in terms of a sphere-converted average particle diameter. On the other hand, the particle diameter of the inorganic particles attached to the mother particles is, for example, in the range of 10 nm to 1 μm (desirably 10 nm to 0.1 μm, more desirably 10 nm to 0.05 μm) in terms of a sphere-converted average particle diameter.

  Next, other additives for the ink receiving particles will be described. First, it is desirable that the ink receiving particles 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 a resin (resin water-absorbing resin) constituting the liquid-absorbent resin particles, 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.

  Specific examples include lithium chloride, sodium chloride, potassium chloride, sodium bromide, potassium bromide, sodium iodide, potassium iodide, sodium sulfate, potassium nitrate, sodium acetate, potassium oxalate, sodium citrate, potassium benzoate and the like. Alkali metal salts and aluminum chloride, aluminum bromide, aluminum sulfate, aluminum nitrate, sodium aluminum sulfate, potassium aluminum sulfate, aluminum acetate, barium chloride, barium bromide, barium iodide, barium oxide, barium nitrate, thiocyanate Barium acid, calcium chloride, calcium bromide, calcium iodide, calcium nitrite, calcium nitrate, calcium dihydrogen phosphate, calcium thiocyanate, calcium benzoate, calcium acetate, salicylic acid Lucium, calcium tartrate, calcium lactate, calcium fumarate, calcium citrate, copper chloride, copper bromide, copper sulfate, copper nitrate, copper acetate, iron chloride, iron bromide, iron iodide, iron sulfate, iron nitrate, oxalic acid Iron, iron lactate, iron fumarate, iron citrate, magnesium chloride, magnesium bromide, magnesium iodide, magnesium sulfate, magnesium nitrate, magnesium acetate, magnesium lactate, manganese chloride, manganese sulfate, manganese nitrate, manganese dihydrogen phosphate , Manganese acetate, manganese salicylate, manganese benzoate, manganese lactate, nickel chloride, nickel bromide, nickel sulfate, nickel nitrate, nickel acetate, tin sulfate, titanium chloride, zinc chloride, zinc bromide, zinc sulfate, zinc nitrate, thiocyanate Examples thereof include salts of polyvalent metals such as zinc acid and zinc acetate.

  Specific examples of organic acids include arginic acid, citric acid, glycine, glutamic acid, succinic acid, tartaric acid, cysteine, oxalic acid, fumaric acid, phthalic acid, maleic acid, malonic acid, lysine, malic acid, and general formula Examples thereof include compounds represented by (1) and derivatives of these compounds.

Here, in the formula, X represents O, CO, NH, NR ₁ , S, or SO ₂ . R ₁ represents an alkyl group, and R ₁ is preferably CH ₃ , C ₂ H ₅ , or C ₂ H ₄ OH. R represents an alkyl group, and R is preferably CH ₃ , C ₂ H ₅ , or C ₂ H ₄ OH. In addition, R may be included in the formula or may not be included. X is preferably CO, NH, NR, O, and more preferably CO, NH, O. M represents a hydrogen atom, an alkali metal or an amine. M is preferably H, Li, Na, K, monoethanolamine, diethanolamine, triethanolamine or the like, more preferably H, Na, K, and still more preferably a hydrogen atom. n is an integer of 3-7. n is preferably a case where the heterocyclic ring is a 6-membered ring or a 5-membered ring, and more preferably a 5-membered ring. m is 1 or 2. The compound represented by the general formula (1) may be a saturated ring or an unsaturated ring as long as it is a heterocyclic ring. l is an integer of 1-5.

  Specifically, the compound represented by the general formula (1) has a furan, pyrrole, pyrroline, pyrrolidone, pyrone, pyrrole, thiophene, indole, pyridine, quinoline structure, and further has a carboxyl group as a functional group. Compounds. Specifically, 2-pyrrolidone-5-carboxylic acid, 4-methyl-4-pentanolide-3-carboxylic acid, furan carboxylic acid, 2-benzofuran carboxylic acid, 5-methyl-2-furan carboxylic acid, 2,5 -Dimethyl-3-furancarboxylic acid, 2,5-furandicarboxylic acid, 4-butanolide-3-carboxylic acid, 3-hydroxy-4-pyrone-2,6-dicarboxylic acid, 2-pyrone-6-carboxylic acid, 4-pyrone-2-carboxylic acid, 5-hydroxy-4-pyrone-5-carboxylic acid, 4-pyrone-2,6-dicarboxylic acid, 3-hydroxy-4-pyrone-2,6-dicarboxylic acid, thiophenecarboxylic Acid, 2-pyrrolecarboxylic acid, 2,3-dimethylpyrrole-4-carboxylic acid, 2,4,5-trimethylpyrrole-3-propionic acid, 3-hydroxy-2-yne Carboxylic acid, 2,5-dioxo-4-methyl-3-pyrroline-3-propionic acid, 2-pyrrolidinecarboxylic acid, 4-hydroxyproline, 1-methylpyrrolidine-2-carboxylic acid, 5-carboxy-1-methyl Pyrrolidine-2-acetic acid, 2-pyridinecarboxylic acid, 3-pyridinecarboxylic acid, 4-pyridinecarboxylic acid, pyridinedicarboxylic acid, pyridinetricarboxylic acid, pyridinepentacarboxylic acid, 1,2,5,6-tetrahydro-1-methyl Examples include nicotinic acid, 2-quinolinecarboxylic acid, 4-quinolinecarboxylic acid, 2-phenyl-4-quinolinecarboxylic acid, 4-hydroxy-2-quinolinecarboxylic acid, and 6-methoxy-4-quinolinecarboxylic acid. .

  The organic acid is preferably citric acid, glycine, glutamic acid, succinic acid, tartaric acid, phthalic acid, pyrrolidone carboxylic acid, pyrone carboxylic acid, pyrrole carboxylic acid, furan carboxylic acid, pyridine carboxylic acid, coumaric acid, thiophene carboxylic acid, Nicotinic acid, derivatives of these compounds, or salts thereof. More desirably, pyrrolidone carboxylic acid, pyrone carboxylic acid, pyrrole carboxylic acid, furan carboxylic acid, pyridine carboxylic acid, coumaric acid, thiophene carboxylic acid, nicotinic acid, or derivatives of these compounds, or salts thereof. More desirable are pyrrolidone carboxylic acid, pyrone carboxylic acid, furan carboxylic acid, coumaric acid, or a derivative of these compounds, or a salt thereof.

  The organic amine compound may be any of primary, secondary, tertiary and quaternary amines and salts thereof. Specific examples include tetraalkylammonium, alkylamine, benzalkonium, alkylpyridium, imidazolium, polyamine, and derivatives or salts thereof. Specifically, amylamine, butylamine, propanolamine, propylamine, ethanolamine, ethylethanolamine, 2-ethylhexylamine, ethylmethylamine, ethylbenzylamine, ethylenediamine, octylamine, oleylamine, cyclooctylamine, cyclobutylamine, cyclohexane Propylamine, cyclohexylamine, diisopropanolamine, diethanolamine, diethylamine, di-2-ethylhexylamine, diethylenetriamine, diphenylamine, dibutylamine, dipropylamine, dihexylamine, dipentylamine, 3- (dimethylamino) propylamine, dimethylethylamine, dimethyl Ethylenediamine, dimethyloctylamine, 1,3-dimethylbutylamine, dimethyl 1,3-propanediamine, dimethylhexylamine, amino-butanol, amino-propanol, amino-propanediol, N-acetylaminoethanol, 2- (2-aminoethylamino) -ethanol, 2-amino-2- Ethyl-1,3-propanediol, 2- (2-aminoethoxy) ethanol, 2- (3,4-dimethoxyphenyl) ethylamine, cetylamine, triisopropanolamine, triisopentylamine, triethanolamine, trioctylamine, Tritylamine, bis (2-aminoethyl) 1,3-propanediamine, bis (3-aminopropyl) ethylenediamine, bis (3-aminopropyl) 1,3-propanediamine, bis (3-aminopropyl) methylamine, Bis (2-ethylhexyl ) Amine, bis (trimethylsilyl) amine, butylamine, butylisopropylamine, propanediamine, propyldiamine, hexylamine, pentylamine, 2-methyl-cyclohexylamine, methyl-propylamine, methylbenzylamine, monoethanolamine, laurylamine, Nonylamine, trimethylamine, triethylamine, dimethylpropylamine, propylenediamine, hexamethylesidiamine, tetraethylenepentamine, diethylethanolamine, tetramethylammonium chloride, tetraethylammonium bromide, dihydroxyethyl stearylamine, 2-heptadecenyl-hydroxyethylimidazoline, lauryl Dimethylbenzylammonium chloride, cetylpyridinium mouth Ride, stearamide methylbiridium chloride, diallyldimethylammonium chloride polymer, diallylamine polymer, monoallylamine polymer and the like can be mentioned.

  More desirably, triethanolamine, triisopropanolamine, 2-amino-2-ethyl-1,3-propanediol, ethanolamine, propanediamine, propylamine and the like are used.

Among these flocculants, polyvalent metal salts (Ca (NO ₃ ), Mg (NO ₃ ), Al (OH ₃ ), polyaluminum chloride, etc.) are preferably used.

  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.

  The ink receiving particles preferably contain a release agent. The release agent may be included in the liquid-absorbent resin, or the release agent particles may be combined with the hydrophilic organic resin particles.

  Examples of the mold release agent include low molecular weight polyolefins such as polyethylene, polypropylene, and polybutene; silicones having a softening point by heating; fatty acid amides such as oleic acid amide, erucic acid amide, ricinoleic acid amide, and stearic acid amide. Plant waxes such as carnauba wax, rice wax, candelilla wax, tree wax, jojoba oil; animal waxes such as beeswax; minerals such as montan wax, ozokerite, ceresin wax, microcrystalline wax, Fischer-Tropsch wax -Petroleum wax; and modified products thereof. Among these, it is preferable to apply a crystalline compound.

  Hereinafter, the ink applied in the above embodiment will be described in detail. Water-based ink is used as the ink. Aqueous ink (hereinafter simply referred to as ink) contains an ink solvent (for example, water, a water-soluble organic solvent) in addition to the recording material. In addition, other additives may be included as necessary.

  First, the recording material will be described. As the recording material, a color material is mainly used. As the color material, either a dye or a pigment can be used, but a pigment is preferable. As the pigment, either an organic pigment or an inorganic pigment can be used. Examples of the black pigment include carbon black pigments such as furnace black, lamp black, acetylene black, and channel black. 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.

  It is also possible to use particles, such as silica, alumina, polymer beads, etc., having a dye or pigment fixed on the surface thereof, a dye insoluble lake, a colored emulsion, or a colored latex as the pigment.

  Specific examples of black pigments include Raven7000, Raven5750, Raven5250, Raven5000 ULTRAII, Raven3500, Raven2000, Raven1500, Raven1250, Raven1200, Raven1125, Raven10, Raven10, Raven10 Regal 330R, Regal 660R, Mogul L, Black Pearls L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 140 0 (manufactured by Cabot Corporation), Color Black FW1, Color Black FW2, Color Black FW2V, Color Black 18, Color Black FW200, Color Black S150, Color Black P160, Color Black P160, Color Black FW2V, Color Black FW2V, Color Black FW200, Color Black FW200 Printex 140V, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 (manufactured by Degussa), No. 25, no. 33, no. 40, no. 47, no. 52, no. 900, no. 2300, MCF-88, MA600, MA7, MA8, MA100 (manufactured by Mitsubishi Chemical Corporation) and the like can be mentioned, 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 color material, it is desirable to use a pigment dispersant together. Examples of the pigment dispersant that can be 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 can be 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 can also be 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. The amount of the pigment dispersant added varies greatly depending on the pigment, so it cannot be generally stated, but generally 0.1 to 100% by mass with respect to the pigment is mentioned.

  A pigment that can be self-dispersed in water can also be used as the color material. A pigment that can be self-dispersed 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, it can be self-dispersed in water by subjecting ordinary so-called pigments to surface modification treatments such as acid / base treatment, coupling agent treatment, polymer graft treatment, plasma treatment, oxidation / reduction treatment, etc. Pigments are obtained.

  Further, as pigments that can be self-dispersed in water, in addition to pigments obtained by subjecting the above pigments to surface modification treatment, Cab-o-jet-200, Cab-o-jet-300, IJX- manufactured by Cabot Corporation Commercially available self-dispersing pigments such as 157, IJX-253, IJX-266, IJX-273, IJX-444, IJX-55, Cabot 260, Microjet Black CW-1, CW-2 manufactured by Orient Chemical Co., etc. can also be 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 can also be 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 may be used. it can.

  In addition, a resin-dispersed pigment in which a polymer substance is physically adsorbed or chemically bonded to the pigment can also be 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, 5 to 30% by mass with respect to the ink.

  The volume average particle diameter of the recording material is, for example, 10 nm or more and 1000 nm or less.

  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 a 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 water-soluble organic solvent will be described. 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 nitrogen-containing solvents include pyrrolidone, N-methyl-2-pyrrolidone, cyclohexyl pyrrolidone, and triethanolamine. Examples of alcohols 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.

  In addition, as the water-soluble organic solvent, propylene carbonate, ethylene carbonate, or the like can be used.

  At least one kind of water-soluble organic solvent may be used. As content of a water-soluble organic solvent, 1 mass% or more and 70 mass% or less are mentioned, for example.

  Next, water will be described. As water, it is desirable to use ion-exchanged water, ultrapure water, distilled water, or ultrafiltered water in order to prevent impurities from being mixed.

  Next, other additives will be described. A surfactant can be added to the ink.

  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.

Specific examples of the surfactant are listed below.
Examples of the anionic surfactant include alkylbenzene sulfonate, alkylphenyl sulfonate, alkylnaphthalene sulfonate, higher fatty acid salt, sulfate of higher fatty acid ester, sulfonate of higher fatty acid ester, sulfuric acid of higher alcohol ether. Ester salts and sulfonates, higher alkyl sulfosuccinates, polyoxyethylene alkyl ether carboxylates, polyoxyethylene alkyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates can be used, preferably , Dodecylbenzenesulfonate, isopropylnaphthalenesulfonate, monobutylphenylphenol monosulfonate, monobutylbiphenylsulfonate, monobutylbiphenylsulfonate, dibutylphenylsulfonate Nord disulfonic acid salts and the like are used.

  Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, poly Oxyethylene glycerin fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene fatty acid amide, alkyl alkanolamide, polyethylene glycol polypropylene glycol block copolymer, acetylene glycol, polyoxyethylene adduct of acetylene glycol Desirably, polyoxyethylene nonyl pheny is preferable. Ether, polyoxyethylene octyl phenyl ether, polyoxyethylene dodecyl phenyl ether, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid alkylolamide, polyethylene glycol polypropylene glycol block copolymer Acetylene glycol and polyoxyethylene adducts of acetylene glycol are used.

  In addition, silicone surfactants such as polysiloxane oxyethylene adducts, fluorine surfactants such as perfluoroalkyl carboxylates, perfluoroalkyl sulfonates, and oxyethylene perfluoroalkyl ethers, spicrispolic acid and rhamnolipids Biosurfactants such as lysolecithin can also be used.

  These surfactants may be used alone or in combination. The hydrophilic / hydrophobic balance (HLB) of the surfactant is preferably in the range of 3 to 20 in consideration of solubility and the like.

  The addition amount of these surfactants is preferably 0.001 to 5% by mass, particularly preferably 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 UV absorbers, chelating agents, and the like can also be added.

  Next, preferred characteristics of the ink will be described. First, the surface tension of the ink is 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 to 30 mPa · s.

Here, as the viscosity, a value measured using a rheomat 115 (manufactured by Contraves) as a measuring device, 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.

  As described above, in the embodiment, the ink droplets 20A are selectively ejected based on the image data from the inkjet recording heads 20 of black, yellow, magenta, and cyan so that a full color image is recorded on the recording medium 8. 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 all the droplet discharge (jetting) apparatuses used industrially.

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

(Examples 1-4, 8, 10-11, Comparative Examples 1-2, Reference Examples 5-7 , 9, 12-14 )
Using a recording apparatus having the same configuration as that of the first embodiment to which the release agent and ink receiving particles according to the conditions of Table 1 are applied (see FIGS. 1 to 3; however, the recording head is only one color of black). Images were formed and evaluated. However, the layer thickness of the release layer (release agent coating amount) by the release agent on the intermediate transfer member is 1 μm, and the layer thickness of the particle layer by ink receiving particles on the intermediate transfer member (supply of ink receiving particles) 15 μm, the ink discharge amount is 1200 × 1200 dpi (dpi: number of dots per inch) and the image area density is 4 pL per pixel, and the recording medium is OK Top Coat N paper (manufactured by Oji Paper Co., Ltd.). . Further, the supply amount on the intermediate transfer member was set as the ink receiving particles and the ink prepared as follows.

-Preparation of ink receiving particles-
-Ink receiving particles A-
Styrene / n-butyl methacrylate / acrylic acid copolymer (polar monomer ratio 50 mol%): 95 parts by mass Amorphous polyester resin (polar monomer ratio 0.5 mol%): 5 parts by mass Paraffin wax (OX-3215 / Nippon Seiwa Co., Ltd.): 1 part by mass

  The above materials were mixed and stirred with a Henschel mixer to obtain a kneaded material. Subsequently, it was put into an extruder and melt kneaded. The obtained kneaded product was cooled and then pulverized using a jet mill. This was applied to an air classifier to obtain particles having a sphere-converted average diameter of 8 μm.

Subsequently, for 100 parts by mass of the particles thus obtained,
Amorphous silica (Aerosil TT600 / Degussa): 1 part by mass Amorphous silica (Aerosil R972 / Degussa): 1 part by mass was mixed by stirring to prepare composite particles having an average sphere equivalent diameter of 10 μm. . Thus, ink receiving particles A were obtained.

-Ink receiving particles B-
-Styrene / n-butyl methacrylate / acrylic acid copolymer (polar monomer ratio 85 mol%): 50 parts by mass- Styrene / n-butyl methacrylate / acrylic acid copolymer (polar monomer ratio 50 mol%): 40 Part by mass / Amorphous polyester resin (polar monomer ratio 0.5 mol%): 5 parts by mass / paraffin wax (OX-3215 / Nippon Seiwa Co., Ltd.): 1 part by mass The above materials are mixed and stirred with a Henschel mixer. A kneaded material was obtained. Subsequently, it was put into an extruder and melt kneaded. The obtained kneaded product was cooled and then pulverized using a jet mill. This was applied to an air classifier to obtain particles having a sphere-converted average diameter of 7 μm.

Subsequently, for 100 parts by mass of the particles thus obtained,
Amorphous silica (Aerosil TT600 / Degussa): 0.5 parts by mass Amorphous silica (Aerosil R972 / Degussa): 1.5 parts by mass is mixed with stirring, and a composite having a sphere equivalent average diameter of 8 μm Particles were made. Thus, ink receiving particles B were obtained.

-Ink receiving particles C-
Styrene / 2-ethylhexyl methacrylate / acrylic acid copolymer (polar monomer ratio 12.5 mol%): 50 parts by mass Styrene / n-butyl methacrylate / acrylic acid copolymer (polar monomer ratio 50 mol%) : 40 parts by mass / paraffin wax (OX-3215 / Nippon Seiwa): 1 part by mass The above materials were mixed and stirred with a Henschel mixer to obtain a kneaded material. Subsequently, it was put into an extruder and melt kneaded. The obtained kneaded product was cooled and then pulverized using a jet mill. This was applied to an air classifier to obtain particles having a sphere-converted average diameter of 8 μm.

Subsequently, for 100 parts by mass of the particles thus obtained,
Amorphous silica (Aerosil TT600 / Degussa): 1 part by mass Amorphous silica (Aerosil R972 / Degussa): 1 part by mass was agitated and mixed to prepare composite particles with an average sphere equivalent diameter of 10 μm. . In this way, ink receiving particles C were obtained.

-Ink receiving particles D-
2,2-azobisisobutyronitrile was added to the styrene / n-butyl methacrylate polymer / acrylic acid copolymer with respect to the styrene / n-butyl methacrylate polymer / acrylic acid copolymer (polar monomer ratio 50 mol%). It added so that it might become 2.5% by mass ratio, and this was melt-mixed with the extruder. The powder thus obtained was pulverized using a jet mill and further classified using an ultrasonic vibration sieve to obtain porous particles having a volume average particle diameter of 8 μm.

Subsequently, for 100 parts by mass of the particles thus obtained,
Amorphous silica (Aerosil TT600 / Degussa): 1.25 parts by mass Amorphous silica (Aerosil R972 / Degussa): 0.75 parts by mass is stirred and mixed, and a composite having a sphere equivalent average diameter of 10 μm Particles were made. In this way, ink receiving particles D were obtained.

-Ink receiving particles E-
Amorphous polyester resin (acid value 5 mg KOH / g): 8 parts by mass Styrene / n-butyl methacrylate polymer / acrylic acid copolymer (polar monomer ratio 50 mol%): 70 parts by mass Amorphous silica ( Aerosil OX50 / Degussa: 20 parts by mass Amorphous silica (Aerosil R972 / Degussa: 2 parts by mass

  The above materials were mixed and stirred with a Henschel mixer to obtain a kneaded material. Subsequently, it was put into an extruder and melt kneaded. The obtained kneaded product was cooled and then pulverized using a jet mill. This was passed through an ultrasonic sieve to obtain organic / inorganic hybrid particles having an average sphere equivalent diameter of 7 μm.

Subsequently, for 100 parts by mass of the particles thus obtained,
Amorphous silica (Aerosil TT600 / Degussa): 1.25 parts by mass Amorphous silica (Aerosil R972 / Degussa): 0.75 parts by mass is stirred and mixed, and a composite having a sphere equivalent average diameter of 9 μm Particles were made. In this way, ink receiving particles E were obtained.

-Preparation of ink-
The following ink components were mixed, stirred, and then filtered using a membrane filter having a pore size of 5 μm to prepare an ink.

-Ink component-
Cyan pigment (CI Pig. Blue 15: 3): 7.5 parts by mass Styrene / acrylic acid (acid value 150 mg KOH / g): 2.5 parts by mass Butyl carbitol: 2.5 parts by mass Diethylene glycol: 10 parts by mass Glycerol: 25 parts by mass Nonionic surfactant (acetylene glycol derivative): 1 part by mass pH adjusting agent, fungicide (Proxel GXL (S) manufactured by Arch Chemicals Japan): Small amount Pure water: 60 Part

  The obtained ink had a surface tension of 33 mN / m, a viscosity of 7.2 mPa · s, a pH of 8.8, and a volume average particle diameter of 92 nm.

(Evaluation)
-Image disturbance (ghost)-
Image disturbance was evaluated as follows. After printing 20 identical images in succession, one different image is printed. A sensory evaluation was performed based on a predetermined limit sample to determine whether an image was formed on the non-image portion of the last printed print sample.
The evaluation criteria are as follows.
○: An image is not confirmed even when a non-image portion is confirmed as an enlarged image.
Δ: When a non-image portion is confirmed as an enlarged image, it is possible to confirm the image, but it cannot be visually determined, and is within an allowable range. Δ-: The image is also formed on the non-image portion visually. However, it is recognized that an image is formed on a non-image part by visual inspection, and the degree is severe and outside the allowable range.

-Image density-
The image density was evaluated as follows. A 100% coverage pattern was printed, and the optical density was measured on the printed portion using X-Rite 404 (manufactured by X-Rite).
The evaluation criteria are as follows.
○: Optical density is 1.4 or more Δ: Optical density is 1.35 or more and less than 1.4 Δ-: Optical density is 1.3 or more and less than 1.35 ×: Optical density is less than 1.3

-Bleeding-
Bleeding was evaluated as follows. A 1-dot line pattern was printed, and sensory evaluation was performed with reference to a limit sample in which the degree of bleeding of the line was determined in advance.
The evaluation criteria are as follows.
○: Bleeding is not confirmed even when the image portion is confirmed as an enlarged image.
Δ: When an image portion is confirmed as an enlarged image, bleeding can be confirmed, but it cannot be visually determined and is within an allowable range. Δ−: Bleeding is visually recognized in the image portion, but the allowable range. Inside x: Bleeding is visually recognized in the image area, and the degree is severe and outside the allowable range

  From the above results, in this embodiment, compared with the comparative example, after transferring to the recording medium, the ink-receptive particles remain on the intermediate transfer body or are cleaned well, and images are continuously formed while preventing image distortion. It turns out that it is possible.

1 is a configuration diagram illustrating a recording apparatus according to a first embodiment. FIG. 3 is a configuration diagram illustrating a main part of the recording apparatus according to the first embodiment. It is a block diagram which shows the ink receptive particle layer which concerns on 1st Embodiment. It is a conceptual diagram which shows an example of the ink receptive particle which concerns on embodiment. It is a conceptual diagram which shows another example of the ink receptive particle which concerns on embodiment.

Explanation of symbols

8 Recording medium 10 Recording device 12 Intermediate transfer member 14 Release agent coating device 14A Release layer 14B Blade 14C Application roller 14D Release agent 16 Ink receiving particle 16A Ink receiving particle layer 16B Image layer 16C Particle layer 16D Residual particle 18 Particle coating device 18A Supply roller 18B Charging blade 19 Ink receiving particle storage cartridge 19A Supply tube 20 Inkjet recording head 20A Ink droplet 22 Transfer fixing device (transfer fixing roller)
22A Heating roll 22B Pressure roll 24 Cleaning device 28 Charging device 29 Neutralizing device 31 Follower roll 100 Ink receiving particles 101 Mother particles 101A Hydrophilic organic particles 101B Inorganic particles constituting the mother particles 102 Inorganic particles adhered to the mother particles

Claims (4)

An intermediate transfer member;
A release agent supply means for supplying a release agent onto the intermediate transfer member;
Particle supplying means for supplying hydrophilic ink receiving particles for receiving ink onto a release agent supplied on the intermediate transfer member;
An ink discharge means for discharging ink to the ink receiving particles supplied on the intermediate transfer member;
Transfer means for transferring the ink receiving particles that have received the ink from an intermediate transfer member to a recording medium;
Have
The releasing agent is, the recording apparatus is an organic compound of soluble Kaido parameter (SP value) 8-11.   The recording apparatus according to claim 1, wherein a solubility parameter (SP value) of the organic compound is 8 to 10. Wherein the viscosity of the release agent, the recording apparatus according to claim 1 or 2 which is 5~200mPa · s. The ink receptive particles are recorded according to the polar monomer claims 1 to 3 any one ratio is contains at least constituting 10 mol% or more 90 mol% or less of the organic resin for total monomer components apparatus.