JP2019019189A - Set of ink and reaction liquid and inkjet recording method - Google Patents

Abstract

To provide a set of ink and reaction liquid capable of suppressing occurrence of void and recording an image excellent in scratch resistance and to provide an inkjet recording method using the set.SOLUTION: There is provided a set of ink and reaction liquid which has a combination of aqueous ink containing a pigment and aqueous reaction liquid reactive with the ink. The reaction liquid contains a reaction agent, resin particles formed of a polyolefin resin and a fluorine-based surfactant and the reaction agent is a hydroxy acid. There is provided an inkjet recording method for recording an image on a recording medium using the set of the ink and the reaction liquid.SELECTED DRAWING: None

Description

  The present invention relates to a set of ink and a reaction liquid, and an ink jet recording method.

  A recording method (inkjet recording method) adopting an ink jet method is useful as a method for directly recording an image on a recording medium into which ink easily penetrates. In recent years, the inkjet recording method has been developed as a method for directly recording an image on a recording medium such as printing paper, which is difficult for ink to penetrate among coated papers. Furthermore, it is also applied to a so-called transfer type recording method in which an ink image recorded on a non-ink-permeable transfer member such as a resin film or silicone rubber is transferred to a recording medium.

  In order to improve fastness such as light resistance, gas resistance and water resistance of the recorded image, a pigment ink containing a pigment is usually used. However, when an image is recorded on a recording medium in which ink does not easily permeate, pigment ink tends to flow and mix on the recording medium due to surface tension, which tends to cause a problem that the quality of the image is lowered. In order to solve such a problem, for example, a recording method using an ink and a liquid composition having an action of aggregating the ink has been proposed (Patent Document 1).

  Further, in order to suppress image shrinkage due to aggregation of the pigment ink, an aggregation treatment agent containing 2-pyrrolidone-5-carboxylic acid as an aggregating agent and further containing polyolefin particles and a fluorosurfactant, and the pigment ink An ink set has been proposed (Patent Document 2). According to Patent Document 2, pigment ink is applied to a semi-solid solution aggregation treatment layer having a water content of 56% or less formed on a transfer body.

JP 2004-010633 A JP 2009-096175 A

  The present inventors directly recorded images on various recording media using the ink set proposed in Patent Document 2. Furthermore, using this ink set, an ink image recorded on a transfer member was transferred to a recording medium to record an image. As a result, it has been found that depending on the type of the recording medium, white spots occur in the image and the scratch resistance of the image becomes insufficient.

  Accordingly, an object of the present invention is to provide a set of an ink and a reaction liquid capable of recording an image with suppressed white spots and having excellent scratch resistance. Another object of the present invention is to provide an ink jet recording method using this ink and reaction liquid set.

  That is, according to the present invention, a set of an ink and a reaction liquid having a combination of an aqueous ink containing a pigment and an aqueous reaction liquid that reacts with the ink, the reaction liquid being a reactant, There is provided a set of an ink and a reaction liquid, which contains resin particles formed of a polyolefin resin and a fluorosurfactant, and the reactive agent is a hydroxy acid.

  According to the present invention, it is possible to provide a set of an ink and a reaction liquid capable of recording an image with suppressed white spots and excellent in scratch resistance. Further, according to the present invention, an ink jet recording method using the set of the ink and the reaction liquid can be provided.

It is a schematic diagram which shows an example of the transfer type inkjet recording device used for the inkjet recording method of this invention. It is a schematic diagram which shows an example of the direct recording type inkjet recording device used for the inkjet recording method of this invention.

  Hereinafter, the present invention will be described in more detail with reference to preferred embodiments. In the present invention, when the compound is a salt, the salt is dissociated into ions in the ink, but it is expressed as “contains a salt” for convenience. In addition, water-based ink for inkjet may be simply referred to as “ink”. Further, the set of ink and reaction liquid may be simply referred to as “set”. Physical property values are values at normal temperature (25 ° C.) unless otherwise specified.

  The inventors of the present invention have used a set of a conventional ink and a reaction liquid, the state of an image directly recorded on a recording medium in which ink does not easily penetrate, and an image recorded by transferring an ink image once formed on a transfer body Each state was observed. As a result, it was found that image shrinkage can be suppressed by using a reaction liquid containing resin particles, but it is also found that resin particles are likely to be unevenly distributed in the image and that the unevenly distributed portions are recognized as white spots. did. In particular, when the set proposed in Patent Document 2 is used, it is necessary to form a semi-solid solution treatment layer having a water content of 56% or less by the reaction solution. For this reason, depending on the composition of the reaction solution, it was found that the resin particles are unevenly distributed at the stage of reducing the moisture when forming the aggregating treatment layer, and white spots become remarkable.

  The present inventors have studied to make the presence state of the resin particles in the image uniform in order to suppress white spots in the image. As a result, it has been found that the use of a reaction solution containing a hydroxy acid as a reactant, resin particles formed of a polyolefin resin, and a fluorosurfactant can suppress white spots in an image.

  Since the pigment that has come into contact with the reactants aggregates, the ink locally increases in viscosity, the fluidity decreases, and an image is recorded. Common reactants include, for example, polyvalent metal ions; organic acids having no hydroxy group such as malonic acid and pyroglutamic acid. The hydroxy acid contained as a reactant in the reaction solution constituting the set of the present invention has a relatively high acidity because an electron-withdrawing hydroxy group is present in the vicinity of the carboxy group. In addition, the pigment to be contained in the water-based ink is usually dispersed by a resin having an anionic group or dispersed by a repulsive force by an anionic group bonded to the particle surface. For this reason, by using a reaction solution containing a hydroxy group as a reactive agent, the anionic group can be converted into an acid type to reduce the dispersion force and promote the aggregation of the pigment. The pigment layer can be formed while suppressing. Furthermore, since the hydroxy acid has higher solubility in water than other organic acids, the reaction solution can be kept stable even if the acid concentration is increased. If a polyvalent metal ion is used as a reactant, it is difficult to spread the reaction solution uniformly on the recording medium even if a fluorosurfactant is used.

  The reaction liquid constituting the set of the present invention contains a fluorosurfactant. By using a fluorinated surfactant, the reaction solution can be uniformly applied to the recording medium. Thereby, the uneven distribution of the resin particles is suppressed without phase separation of the hydroxy acid and the resin particles on the recording medium. As described above, since the pigment is aggregated around the resin particles that are uniformly distributed with the uneven distribution suppressed, it is possible to record an image in which white spots are suppressed and scratch resistance is improved.

  Since the reaction liquid constituting the set of the present invention contains a fluorosurfactant, the hydroxy acid and the resin particles are spread uniformly without being unevenly distributed on the recording medium. In this state, since the ink comes into contact with the ink containing the pigment, the pigment quickly aggregates due to the effect of the hydroxy acid, and forms a pigment layer together with the resin particles present uniformly. Furthermore, since the reaction liquid contains resin particles formed of a polyolefin resin, it is considered that the frictional resistance of the recorded image is lowered and the scratch resistance is improved.

<Set of ink and reaction liquid>
The ink and reaction liquid set of the present invention includes a combination of an aqueous ink containing a pigment and an aqueous reaction liquid that reacts with the ink. The reaction liquid contains a reactive agent, resin particles formed of a polyolefin resin, and a fluorosurfactant. In addition, the reactant is a hydroxy acid. Hereinafter, each component used for the ink and reaction liquid which comprise the set of this invention is demonstrated in detail.

(Reaction solution)
The reaction liquid reacts with the ink by coming into contact with the ink and agglomerates the components in the ink (components having an anionic group such as a pigment or resin) and contains a reactive agent. Since the reaction liquid is used in combination with an ink containing a pigment, it is preferable that the reaction liquid does not substantially contain a coloring material such as a pigment. In consideration of the effect on the recorded image, the reaction solution is preferably colorless so as not to substantially absorb in the visible light region. However, it may be a light color having absorption in the visible light region as long as it does not affect the recorded image.

[Reactant]
The reaction solution constituting the set of the present invention contains a hydroxy acid as a reactant. A reaction solution containing an organic acid such as a hydroxy acid has a buffering ability in an acidic region (usually less than pH 7.0, preferably pH 2.0 to 5.0), thereby efficiently treating anionic groups of components in the ink. Aggregate well into acid form. Examples of the hydroxy acid include malic acid, tartaric acid, lactic acid, glycolic acid, glyceric acid, hydroxybutyric acid, citric acid, salicylic acid, and the like.

  The content (% by mass) of hydroxy acid in the reaction solution is preferably 12.0% by mass or more based on the total mass of the reaction solution. When the content of the hydroxy acid is less than 12.0% by mass, the amount of the hydroxy acid may be insufficient and the pigment may not be uniformly aggregated. For this reason, the effect of suppressing white spots in the image and the effect of improving the scratch resistance may be slightly insufficient. The content (% by mass) of the hydroxy acid in the reaction solution is preferably 50.0% by mass or less based on the total mass of the reaction solution.

[Resin particles]
The reaction solution contains resin particles formed of a polyolefin resin. The polyolefin resin forming the resin particles is a component generally called “wax”. Examples of the polyolefin resin include polymers of α-olefins such as ethylene, propylene, 1-butene, 1-pentene, and 1-hexene. Specific examples of the polyolefin resin (wax) include oxidized polyolefin wax, high-density polyolefin wax, a mixture of oxidized polyolefin wax and paraffin wax, and a copolymer of polyolefin and acrylic. Of these, it is preferable to use oxidized polyethylene wax. That is, the polyolefin resin is preferably a polyethylene resin. In addition, it is preferable to use resin particles emulsified (dispersed) with a nonionic emulsifier because the scratch resistance of the recorded image is further improved. Resin particles that are stabilized in the reaction solution by the action of ionic groups, since the reaction between the ionic groups of the resin particles and the pigment gradually progresses even after the pigment is aggregated by the reactant, the aggregation further proceeds. The flexibility of the formed pigment layer may be slightly reduced. In contrast, the resin particles dispersed (emulsified) by the action of the emulsifier are less likely to agglomerate due to the reaction between the resin particles and the pigment than in the above case, and the flexibility of the pigment layer is relatively high. This is presumed to further improve the scratch resistance of the image.

  The 50% particle diameter (D50) based on the volume distribution of the resin particles is preferably 20 nm or more and 200 nm or less. When the particle diameter (D50) of the resin particles is less than 20 nm, the effect of improving the scratch resistance may be slightly weakened because the particle diameter is too small. On the other hand, if the particle diameter (D50) of the resin particles is more than 200 nm, the resin particles themselves may be too large to be recognized as white spots. The particle diameter (D50) of the resin particles can be measured using, for example, a particle size analyzer by a dynamic light scattering method.

  The content (% by mass) of the resin particles in the reaction solution is preferably 5.0% by mass or more based on the total mass of the reaction solution. When the content of the resin particles is less than 5.0% by mass, the resin particles are insufficient, and thus the effect of improving the scratch resistance of the image may be slightly insufficient. The content (% by mass) of the resin particles in the reaction solution is preferably 30.0% by mass or less based on the total mass of the reaction solution.

  The content (% by mass) of the hydroxy acid in the reaction solution is preferably 1.0 times or more and 8.0 times or less as a mass ratio with respect to the content (% by mass) of the resin particles. When the above mass ratio is 1.0 times or more, uneven distribution of the resin particles is efficiently suppressed, so that white spots can be more effectively suppressed and the scratch resistance is particularly easily improved. On the other hand, when the mass ratio is more than 8.0 times, the amount of pigment in the pigment layer is increased, and the amount of resin particles is relatively reduced. For this reason, the scratch resistance of the image may be slightly lowered.

[Fluorosurfactant]
The reaction solution contains a fluorosurfactant. As the fluorosurfactant, a surfactant having a perfluoroalkyl group is preferable. By using a surfactant having a perfluoroalkyl group, it is possible to effectively reduce the surface tension of the reaction solution and to make the hydroxy acid and the resin particles more evenly present on the recording medium. Examples of the surfactant having a perfluoroalkyl group include perfluoroalkyl sulfonic acids, perfluoroalkyl carboxylic acids, and perfluoroalkyl phosphate esters. Of these, nonionic fluorosurfactants are preferred. When an ionic fluorosurfactant is used, the aggregation of the pigment layer is further facilitated by the aggregated pigment and the ionic fluorosurfactant, so the flexibility of the pigment layer may be slightly reduced. . The content (% by mass) of the fluorosurfactant in the reaction solution is preferably 5.0% by mass or more and 30.0% by mass or less based on the total mass of the reaction solution.

  The content (mass%) of the resin particles in the reaction liquid is preferably 1.0 times or more and 12.0 times or less as a mass ratio with respect to the content (mass%) of the fluorosurfactant. The surface tension of the reaction solution can be greatly reduced by adding a small amount of the fluorosurfactant. For this reason, when the above-mentioned mass ratio is more than 12.0 times, it becomes somewhat difficult to efficiently spread the resin particles, and the effect of suppressing white spots may be slightly insufficient. On the other hand, if the mass ratio is less than 1.0 times, the amount of the fluorosurfactant relative to the resin particles is too large, so that even if the pigment aggregates around the resin particles, the resin particles are likely to be unevenly distributed. Therefore, the white spot suppression effect may be slightly insufficient.

[Other ingredients]
The reaction solution may contain various other components as necessary. Examples of the other components include the same aqueous media described later that can be contained in the ink, and other components.

  As described above, the reaction solution containing a hydroxy acid has a buffering capacity in an acidic region (usually less than 7.0, preferably pH 2.0 to 5.0), thereby efficiently removing anionic groups of components in the ink. Aggregate well into acid form. For this reason, in order to maintain good reactivity, it is preferable to adjust the pH of the reaction solution. Therefore, pH adjusting agents such as alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; alkaline earth metal hydroxides such as calcium hydroxide can be contained in the reaction agent.

(ink)
The ink constituting the set of the present invention is a water-based ink containing a pigment.

[Pigment]
The ink contains a pigment as a coloring material. The content of the pigment in the ink is preferably 0.5% by mass or more and 15.0% by mass or less, and preferably 1.0% by mass or more and 10.0% by mass or less, based on the total mass of the ink. Further preferred.

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

  As a dispersion method of the pigment, a resin dispersion pigment using a resin as a dispersant, a self-dispersion pigment in which a hydrophilic group is bonded to the pigment particle surface, or the like can be used. Further, a resin-bonded pigment in which an organic group containing a resin is chemically bonded to the pigment particle surface, a microcapsule pigment in which the pigment particle surface is coated with a resin, or the like can also be used. It is preferable to use a dispersion method using a resin dispersant because the reactivity with a reaction solution containing a hydroxy acid is good and the scratch resistance of an image is easily improved.

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

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

[resin]
The ink can contain a resin. The content (% by mass) of the resin in the ink is preferably 0.1% by mass or more and 20.0% by mass or less, and 0.5% by mass or more and 15.0% by mass or less based on the total mass of the ink. More preferably.

  The resin can be added to the ink (i) in order to stabilize the dispersion state of the pigment, that is, the above-described resin dispersant or as an auxiliary thereto. Further, (ii) it can be added to the ink in order to improve various characteristics of the recorded image. Examples of the form of the resin include a block copolymer, a random copolymer, a graft copolymer, and combinations thereof. The resin may be a water-soluble resin that can be dissolved in an aqueous medium, or may be resin particles that are dispersed in an aqueous medium. The resin particles do not need to include a color material.

  In the present invention, that the resin is water-soluble means that, when the resin is neutralized with an alkali equivalent to the acid value, it does not form particles whose particle diameter can be measured by a dynamic light scattering method. To do. Whether or not the resin is water-soluble can be determined according to the following method. First, a liquid (resin solid content: 10% by mass) containing a resin neutralized with an alkali corresponding to an acid value (sodium hydroxide, potassium hydroxide, etc.) is prepared. Next, the prepared liquid is diluted 10 times (volume basis) with pure water to prepare a sample solution. And when the particle diameter of resin in a sample solution is measured by a dynamic light scattering method, when the particle | grains which have a particle diameter are not measured, it can be judged that the resin is water-soluble. The measurement conditions at this time can be set, for example, as SetZero: 30 seconds, the number of measurements: 3 times, and the measurement time: 180 seconds. As the particle size distribution measuring apparatus, a particle size analyzer (for example, trade name “UPA-EX150”, manufactured by Nikkiso) using a dynamic light scattering method can be used. Of course, the particle size distribution measuring apparatus and measurement conditions to be used are not limited to the above.

  The acid value of the resin is preferably from 100 mgKOH / g to 250 mgKOH / g in the case of a water-soluble resin, and preferably from 5 mgKOH / g to 100 mgKOH / g in the case of a resin particle. The weight average molecular weight of the resin is preferably 3,000 to 15,000 in the case of a water-soluble resin, and preferably 1,000 to 2,000,000 in the case of a resin particle. The 50% particle diameter (D50) based on the volume distribution measured by the dynamic light scattering method of resin particles (measurement conditions are the same as above) is preferably 50 nm or more and 500 nm or less.

  Examples of the resin include acrylic resins, urethane resins, and olefin resins. Of these, acrylic resins and urethane resins are preferable.

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

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

  The urethane resin can be obtained, for example, by reacting a polyisocyanate and a polyol. Further, it may be further reacted with a chain extender. Examples of the olefin resin include polyethylene and polypropylene.

[Aqueous medium]
The ink constituting the set of the present invention is an aqueous ink containing an aqueous medium that is a mixed solvent of water and a water-soluble organic solvent. As water, deionized water or ion exchange water is preferably used. The content (% by mass) of water in the ink is preferably 50.0% by mass or more and 95.0% by mass or less based on the total mass of the ink. The content (% by mass) of the water-soluble organic solvent in the ink is preferably 3.0% by mass or more and 50.0% by mass or less based on the total mass of the ink. As the water-soluble organic solvent, any of those usable for ink-jet inks such as alcohols, (poly) alkylene glycols, glycol ethers, nitrogen-containing compounds and sulfur-containing compounds can be used.

[Other ingredients]
The ink contains various additives such as antifoaming agents, surfactants, pH adjusting agents, viscosity adjusting agents, rust preventing agents, antiseptics, antifungal agents, antioxidants, and reducing agents as required. May be.

<Inkjet recording method>
The ink jet recording method of the present invention (hereinafter, also simply referred to as “recording method”) is an ink jet recording method in which an image is recorded on a recording medium by bringing an ink and a reaction liquid into contact with each other. And the set of the above-mentioned ink and reaction liquid is used as ink and reaction liquid. The recording method of the present invention may be any of the following methods (1) and (2).
(1) A method of recording an image by transferring an ink image formed by applying a reaction liquid and ink to a first recording medium (transfer body) onto a recording medium. (2) A reaction liquid without using a transfer body or the like. And method for recording an image by directly applying ink to a recording medium

  Hereinafter, the configuration of the ink jet recording apparatus that can be used in the methods (1) and (2) will be described. For convenience, the ink jet recording apparatus usable in the method (1) is referred to as a “transfer ink jet recording apparatus”; the ink jet recording apparatus usable in the method (2) is referred to as a “direct recording ink jet recording apparatus”.

(Transfer type inkjet recording device)
FIG. 1 is a schematic view showing an example of a transfer type ink jet recording apparatus used in the ink jet recording method of the present invention. A transfer type inkjet recording apparatus 100 shown in FIG. 1 is a single-wafer type inkjet recording apparatus that manufactures a recorded material by transferring an ink image to a recording medium 108 via a transfer body 101. The X direction, the Y direction, and the Z direction indicate the width direction (full length direction), the depth direction, and the height direction of the transfer type inkjet recording apparatus 100, respectively. The recording medium is conveyed in the X direction.

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

  The transfer body 101 rotates in the direction of arrow A about the rotation shaft 102 a of the support member 102. After the reaction liquid is applied from the reaction liquid applying device 103 to the rotating transfer body 101, ink is applied from the ink applying apparatus 104, whereby an ink image is formed on the transfer body 101. The ink image formed on the transfer body 101 moves to a position where it contacts the liquid absorbing member 105 a of the liquid absorbing device 105 by the rotation of the transfer body 101.

  The liquid absorbing member 105 a constituting the liquid absorbing device 105 moves (rotates) in the direction of arrow B in synchronization with the rotation of the transfer body 101. The ink image formed on the transfer body 101 is in contact with the moving liquid absorbing member 105a. Meanwhile, the liquid absorbing member 105a absorbs and removes the liquid component from the ink image. From the viewpoint of efficiently absorbing the liquid component of the ink image, the liquid absorbing member 105a is preferably pressed against the transfer body 101 with a predetermined pressing force. The ink image is formed of ink and reaction liquid. Therefore, absorbing the liquid component of the ink image means absorbing the liquid component in the ink and the reaction liquid. It can be said that the absorption of the liquid component from the ink image is the concentration of the ink or the like. Concentration of ink or the like increases the ratio of solid components such as color materials and resins to liquid components.

  The ink image in which the liquid component is removed and the ink is concentrated moves to the transfer unit 111 that contacts the recording medium 108 conveyed by the recording medium conveying device 107 by the rotation of the transfer body 101. The ink image and the recording medium 108 are pressed and contacted from the pressing member 106 side while being sandwiched between the transfer body 101 and the pressing member 106. When the roller-shaped transfer body 101 and the columnar pressing member 106 are used, the ink image and the recording medium 108 are linearly contacted along the Y direction. When the transfer body 101 made of an elastic material is used, the transfer body 101 is recessed by pressing, so that the ink image and the recording medium 108 come into contact with each other on the surface. Therefore, a line or surface where the ink image and the recording medium 108 come into contact with each other is referred to as an “area”, and a portion including this area is referred to as a transfer unit 111. While the ink image is in contact with the recording medium 108, the pressing member 106 presses the transfer body 101, whereby the ink image is transferred to the recording medium 108 and a desired image is recorded on the recording medium 108. The image after transfer is a reverse image of the ink image before transfer.

  When the reaction liquid is applied to the transfer body using the roller-shaped reaction liquid applying member 103c, the reaction liquid is applied to the entire transfer body. In order to form an ink image by applying ink to the transfer body to which the reaction liquid has been applied, the reaction liquid that has not reacted with the ink remains in the area of the transfer body to which ink has not been applied. The liquid absorbing member 105a can remove not only the ink image but also the liquid component of the unreacted reaction liquid. The liquid component contained in the ink or the reaction liquid does not have a certain shape but has fluidity and exists in a substantially constant volume. The liquid component contained in the ink or the reaction liquid is specifically an aqueous medium.

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

[1] Transfer Body The transfer body 101 has a surface layer including a surface on which an ink image is formed. Examples of the material constituting the surface layer include resins and ceramics. A resin having a siloxane structure is preferable, and a material having a high compression elastic modulus is preferable from the viewpoint of durability and the like. In order to improve the wettability and transferability of the reaction solution, surface treatment may be performed.

  The transfer body preferably has a compression layer having a function of absorbing pressure fluctuation between the surface layer and the support member. The compression layer disperses local pressure fluctuations and absorbs deformation of the surface layer. For this reason, by providing a compression layer, good transferability can be maintained even when high-speed recording is performed. Examples of the material constituting the compression layer include elastic materials such as rubber materials. Among these, a rubber material having a porous structure formed by blending a raw material rubber with a filler such as a foaming agent, hollow fine particles, and a salt together with a vulcanizing agent and a vulcanization accelerator is preferable. In such an elastic material, when the pressure fluctuates, the void portion is compressed with a change in volume, so that deformation in the direction other than the compression direction is small. For this reason, transferability and durability can be improved. Examples of the porous structure include a continuous void structure in which voids are connected to each other, and an independent void structure in which voids are independent from each other.

  The transfer body preferably further has an elastic layer between the surface layer and the compression layer. Examples of the material constituting the elastic layer include a resin material and a ceramic material. Among them, an elastic material such as a rubber material is preferable because it is easy to process, changes in elastic modulus with temperature are small, and has excellent transferability.

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

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

[3] Reaction liquid applying apparatus The ink jet recording method of the present invention preferably has a reaction liquid applying step of applying a reaction liquid to a recording medium or a transfer body before the image forming step. The reaction liquid contains a reactive agent that reacts with the ink by coming into contact with the ink and aggregates components having an anionic group such as a resin and a self-dispersing pigment in the ink. In the image forming step, it is preferable to apply ink to the recording medium or the transfer body so that at least a part of the region to which the reaction liquid is applied overlaps. After applying the ink, the reaction liquid may be further applied so that at least a part of the region where the ink is applied overlaps.

  A transfer type inkjet recording apparatus 100 shown in FIG. 1 includes a reaction liquid applying device 103 that applies a reaction liquid to a transfer body 101. The reaction liquid application device 103 is a gravure offset roller having a reaction liquid storage part 103a that stores the reaction liquid and reaction liquid application members 103b and 103c that apply the reaction liquid in the reaction liquid storage part 103a to the transfer body 101. . Examples of the reaction liquid applying device include a gravure offset roller, an ink jet recording head, and the like. Especially, it is preferable to apply a reaction liquid to a transfer body using a roller.

[4] Ink Application Device The transfer type inkjet recording apparatus 100 shown in FIG. 1 includes an ink application device 104 that is an ink application unit that applies ink to the transfer body 101. It is preferable to use an ink jet recording head as the ink application device and apply the ink by ejecting the ink. Examples of the recording head include a mode in which ink is ejected by forming a bubble by forming a film in the ink using an electro-thermal converter; a mode in which ink is ejected by an electro-mechanical converter; and an ink using static electricity. The form which discharges can be mentioned. Among these, a recording head using an electro-thermal converter is preferable because it can record a high-density image at a higher speed.

  The recording head is a full line head extending in the Y direction, and discharge ports are arranged in a range that covers the width of the image recording area of the maximum size recording medium that can be used. The recording head has an ejection port surface with an ejection port opened on the lower surface (transfer body 101 side). The discharge port surface faces the surface of the transfer body 101 with a minute gap (several millimeters).

  The ink applicator 104 may have a plurality of recording heads in order to apply ink of each color such as cyan, magenta, yellow, and black (CMYK) to the transfer body 101. For example, when an ink image is formed using four types of CMYK inks, the ink application device includes four recording heads that respectively discharge the four types of CMYK inks. These recording heads are arranged along the X direction.

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

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

  The liquid absorbing member 105 a rotates in conjunction with the rotation of the transfer body 101. For this reason, the shape of the liquid absorbing member 105a is preferably a shape capable of repeatedly absorbing liquid, and specific examples include an endless belt shape and a drum shape. The liquid component absorbed in the liquid absorbing member 105a including the porous layer is removed from the liquid absorbing member 105a by a method of absorbing from the back surface of the porous layer or a method of using a member that handles the porous member. Can do. After removing the liquid component, the liquid component contained in the ink image can be efficiently absorbed by rotating the liquid absorbing member 105a to contact the new ink image.

[6] Pressing member The transfer type ink jet recording apparatus 100 shown in FIG. 1 includes a transfer unit that transfers an ink image in contact with a recording medium. Specifically, as shown in FIG. 1, the ink image after the removal of the liquid on the transfer body 101 is brought into contact with the recording medium 108 conveyed by the recording medium conveying device 107 by the pressing member 106 at the transfer unit 111 and transferred. To do. By transferring the ink image from which the liquid component has been removed to the recording medium 108, curling or cockling of the recording medium 108 can be suppressed.

  The pressing member 106 preferably has an appropriate structural strength from the viewpoint of conveyance accuracy and durability of the recording medium 108. Examples of the material of the pressing member 106 include metal, ceramic, and resin. Among these, metals such as aluminum are preferable from the viewpoint of not only having rigidity and dimensional accuracy that can withstand the stress during transfer but also reducing inertia during operation and improving control responsiveness.

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

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

  The temperature at which the pressing member 106 presses the transfer body 101 is preferably set to a temperature equal to or higher than the glass transition point (or softening point) of the resin component included in the ink image. Depending on the characteristics of the resin component, in order to control the temperature, the recording apparatus preferably includes a heating unit that heats the ink image on the transfer body 101, the transfer body 101, and the recording medium 108. Examples of the shape of the pressing member 106 include a roller shape.

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

[8] Recording Medium Conveying Device The recording medium conveying device 107 that conveys the recording medium 108 conveys the recording medium 108 in the direction of arrow C. The recording medium conveying device 107 is configured by a recording medium feeding roller 107a and a recording medium winding roller 107b. The conveyance speed of the recording medium 108 is preferably determined in consideration of the speed required in each process.

[9] Cleaning Device As shown in FIG. 1, the recording device of the present invention preferably further includes a cleaning device that is a cleaning unit that applies an aqueous cleaning liquid to the transfer body 101 for cleaning. The cleaning apparatus includes, for example, a transfer body cleaning member 109 that applies a cleaning liquid to the transfer body 101 and cleans it. By cleaning the transfer body 101 with the transfer body cleaning member 109, it is possible to suppress a reduction in image quality. As the cleaning member 109, a member having a shape such as a roller or a web can be used. The cleaning apparatus can be provided with a cleaning liquid supply unit that supplies a cleaning liquid to the transfer member cleaning member 109.

  Furthermore, it is preferable that the cleaning apparatus includes a cleaning liquid removing member 110 that removes the cleaning liquid and the residue remaining on the transferred transfer body 101 after cleaning. By removing the cleaning liquid remaining on the transfer body 101 by the cleaning liquid removing member 110, it is possible to more effectively suppress the deterioration of the image quality. Examples of methods for removing the cleaning liquid remaining on the transfer body 101 include blade removal, brush removal, and liquid absorption by an absorber. In particular, it is preferable to remove the cleaning liquid remaining on the transfer body 101 due to liquid absorption by the absorber. As the cleaning liquid absorbing member 110, a porous body used as a liquid absorbing member can be used.

(Direct recording type inkjet recording device)
FIG. 2 is a schematic view showing an example of a direct recording type ink jet recording apparatus used in the ink jet recording method of the present invention. The direct recording type ink jet recording apparatus 200 shown in FIG. 2 does not include the transfer body 101, the support member 102, the pressing member 106, and the cleaning member 109 shown in FIG. Except for directly recording an image on the recording medium 208, it has the same configuration as the transfer type inkjet recording apparatus 100 shown in FIG. For this reason, the liquid absorbing device 205 that absorbs the liquid component contained in the ink image (image) by the reaction liquid applying device 203, the ink applying device 204, and the liquid absorbing member 205a is the same as that of the transfer type inkjet recording device 100 shown in FIG. It has the same configuration as the above. Therefore, description of these devices is omitted. In FIG. 2, reference numeral 203 a is a reaction liquid container, and reference numerals 203 b and 203 c are reaction liquid application members.

  The liquid absorbing device 205 includes a liquid absorbing member 205 a and a pressing member 205 b that presses the liquid absorbing member 205 a against the ink image (image) of the recording medium 208. The shapes of the liquid absorbing member 205a and the pressing member 205b are not particularly limited, and those having the same shape as the liquid absorbing member and the pressing member that can be used in the transfer type inkjet recording apparatus 100 can be used. In FIG. 2, reference numerals 205c, 205d, 205e, 205f, and 205g denote stretching rollers as stretching members. A support member (not shown) that supports the recording medium from below may be provided in the ink application unit that applies ink to the recording medium 208 by the ink application device 204. In addition, a support member (not shown) that supports the recording medium from below may also be provided in the liquid component removing unit that removes the liquid component by bringing the liquid absorbing member 205a into contact with the ink image of the recording medium.

  The configuration of the recording medium conveying device 207 is not particularly limited, and a conveying unit in a known direct recording type inkjet recording device can be used. Specifically, a recording medium conveying device 207 having a recording medium feeding roller 207a, a recording medium winding roller 207b, and recording medium conveying rollers 207c, 207d, 207e, and 207f as shown in FIG.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated further in detail, this invention is not limited at all by the following Example, unless the summary is exceeded. What is described as “parts” and “%” with respect to the component amounts is based on mass unless otherwise specified.

<Preparation of pigment dispersion>
(Pigment dispersion 1)
A styrene-ethyl acrylate-acrylic acid copolymer (resin 1) having an acid value of 150 mgKOH / g and a weight average molecular weight of 8,000 was prepared. After neutralizing 20.0 parts of resin 1 with potassium hydroxide equimolar to its acid value, an appropriate amount of pure water is added, and an aqueous solution of resin 1 having a resin (solid content) content of 20.0% Was prepared. 10.0 parts of pigment (CI pigment blue 15: 3), 15.0 parts of an aqueous solution of resin 1 and 75.0 parts of pure water were mixed to obtain a mixture. The obtained mixture and 200 parts of 0.3 mm diameter zirconia beads were placed in a batch type vertical sand mill (manufactured by IMEX) and dispersed for 5 hours while cooling with water. After removing coarse particles by centrifugation, pressure filtration with a cellulose acetate filter having a pore size of 3.0 μm (manufactured by Advantech), the content of the pigment is 10.0%, the content of the resin dispersant (resin 1) A pigment dispersion 1 having an amount of 3.0% was prepared.

(Pigment dispersion 2)
The pigment is C.I. I. A pigment dispersion in which the pigment content is 10.0% and the resin dispersant (resin 1) content is 3.0% in the same procedure as the pigment dispersion liquid 1 except that the pigment red 122 is used. Liquid 2 was prepared.

(Pigment dispersion 3)
The pigment is C.I. I. Pigment dispersion with a pigment content of 10.0% and a resin dispersant (resin 1) content of 3.0% in the same procedure as the pigment dispersion 1 except that the pigment yellow 74 was changed. Liquid 3 was prepared.

(Pigment dispersion 4)
A pigment having a pigment content of 10.0% and a resin dispersant (resin 1) content of 3.0% in the same procedure as the pigment dispersion liquid 1 except that the pigment is changed to carbon black. Dispersion 4 was prepared.

(Pigment dispersion 5)
After stirring 300 g of pigment (carbon black) in 1,000 mL of water, 450 g of an aqueous sodium hypochlorite solution (effective chlorine concentration 12%) was added dropwise and stirred at 100 to 105 ° C. for 10 hours. After purification by ultrafiltration, an appropriate amount of ion-exchanged water was added to adjust the pigment content to obtain pigment dispersion 5 having a pigment content of 10.0%.

<Preparation of resin particles for ink>
In a four-necked flask equipped with a stirrer, a reflux condenser, and a nitrogen gas inlet tube, 18.0 parts of butyl methacrylate, 2.0 parts of a polymerization initiator, and 2.0 parts of n-hexadecane are placed, and nitrogen gas is added. The mixture was stirred for 0.5 hour while being introduced. As the polymerization initiator, 2,2′-azobis (2-methylbutyronitrile) was used. Next, 78.0 parts of a 6.0% aqueous solution of an emulsifier (trade name “NIKKOL BC15”, manufactured by Nikko Chemicals) was dropped, and the mixture was stirred for 0.5 hour to obtain a mixture. The mixture was emulsified by irradiating ultrasonic waves for 3 hours using an ultrasonic irradiator, and then subjected to a polymerization reaction at 80 ° C. for 4 hours in a nitrogen atmosphere. After cooling to 25 ° C. and filtering, an appropriate amount of pure water was added to prepare an aqueous dispersion of resin particles A having a resin particle A (solid content) content of 40.0%.

<Preparation of ink>
Each component (unit:%) shown in Table 1 was mixed and stirred sufficiently, and then pressure filtration was performed with a cellulose acetate filter (manufactured by Advantech) having a pore size of 3.0 μm to prepare each ink. In Table 1, “acetylenol E100” is a trade name of a surfactant (manufactured by Kawaken Fine Chemicals).

<Preparation of resin particles for reaction solution>
(Resin particles 1 to 7 and 9)
Oxidized polyethylene wax or oxidized polypropylene wax was emulsified in the presence of a nonionic emulsifier. During emulsification, the temperature and pressure were adjusted as appropriate to control resin particles having a predetermined particle size. An appropriate amount of pure water was added to prepare an aqueous dispersion of resin particles having a resin particle (solid content) content of 50.0%.

(Resin particles 8, 11, and 12)
The concentration of the aqueous dispersion of commercially available resin particles was adjusted to prepare an aqueous dispersion of resin particles having a resin particle (solid content) content of 50.0%.

(Resin particles 10)
In a four-necked flask equipped with a stirrer, a reflux condenser, and a nitrogen gas introduction tube, 18.0 parts of butyl methacrylate, 0.35 part of methacrylic acid, 2.0 parts of a polymerization initiator, and n-hexadecane 2.0 The mixture was stirred for 0.5 hour while introducing nitrogen gas into the reaction system. As the polymerization initiator, 2,2′-azobis (2-methylbutyronitrile) was used. Next, 78.0 parts of a 6.0% aqueous solution of an emulsifier (trade name “NIKKOL BC15”, manufactured by Nikko Chemicals) was dropped, and the mixture was stirred for 0.5 hour to obtain a mixture. The mixture was emulsified by irradiating ultrasonic waves for 3 hours using an ultrasonic irradiator, and then subjected to a polymerization reaction at 80 ° C. for 4 hours in a nitrogen atmosphere. After cooling to 25 ° C. and filtering, an appropriate amount of pure water was added to prepare an aqueous dispersion of resin particles 10 having a resin particle 10 (solid content) content of 50.0%.

<Measurement of particle diameter of resin particles>
The particle diameter (volume average particle diameter) of the resin particles in the aqueous dispersion was measured by the following procedure. The aqueous dispersion of resin particles was diluted with ion exchange water to obtain a liquid having a resin (solid content) content of 1.0%. Using a particle size analyzer (trade name “UPA-EX150”, manufactured by Nikkiso Co., Ltd.) by a dynamic light scattering method, the particle size of resin particles (SetZero: 30 seconds, number of measurements: 3 times, measurement time: 180 seconds) Volume average particle diameter) was measured.

  The properties of the prepared resin particles 1 to 12 are shown in Table 2.

<Surfactant>
Table 3 shows the characteristics of the surfactant used for preparing the reaction solution.

<Preparation of reaction solution>
Each component (unit:%) shown in the middle row of Tables 4-1 to 4-4 is mixed and sufficiently stirred, and then subjected to pressure filtration with a cellulose acetate filter having a pore size of 3.0 μm (manufactured by Advantech) to obtain a reaction solution. Was prepared. In Tables 4-1 to 4-4, the trade name “PAA-HCL-01” (manufactured by Nittobo) was used as “polyallylamine”.

<Evaluation>
The ink and the reaction liquid were used as a set of combinations shown in Table 5. With respect to one set, an image was recorded using a transfer ink jet recording apparatus and a direct recording ink jet recording apparatus, and each evaluation shown below was performed. And the evaluation result with the lower evaluation (rank) was adopted. In the present invention, “A” and “B” are acceptable levels and “C” is an unacceptable level in the evaluation criteria for the following items. The evaluation results are shown in Table 5.

First, an image was recorded using the direct recording type ink jet recording apparatus 200 shown in FIG. The reaction liquid applying device 203, the ink applying device 204, the conveyance speed of the recording medium, and the liquid absorbing device 205 are the same as those of the transfer type ink jet recording apparatus shown in FIG. As the recording medium 208, coated paper (trade name “Gloria Pure White Paper”, manufactured by Gojo Paper Co., Ltd., basis weight 210 g / m ² ) was used. In the direct recording type inkjet recording apparatus 200, an image recorded under the condition of applying 3.0 ng ink droplets to a unit area of 1/1200 inch × 1/1200 inch is defined as a recording duty of 100%. A solid image of 5 cm × 5 cm having a recording duty of 100% and a recording duty of 100% was recorded on the recording medium 208.

  Next, an image was recorded using the transfer type inkjet recording apparatus 100 shown in FIG. As the support member 102, a cylindrical drum made of an aluminum alloy was used. As a surface layer member of the transfer body 101, a polyethylene terephthalate film having a thickness of 0.5 mm and a silicone rubber having a rubber hardness (durometer type A) of 40 ° (trade name “KE12”, manufactured by Shin-Etsu Chemical Co., Ltd.) are 0.2 mm. What was coated to the thickness of was used.

This surface layer member is subjected to plasma surface treatment under the conditions of treatment distance: 5 mm, plasma mode: high, treatment speed: 100 mm / sec, using an atmospheric pressure plasma treatment apparatus (trade name “ST-7000”, manufactured by Keyence). gave. Furthermore, the surface of the surface layer member was immersed in a surfactant aqueous solution prepared by diluting with pure water so that the concentration of a commercially available neutral detergent (sodium alkylbenzenesulfonate) was 3%, and then dried. The surface layer member of the transfer body 101 was used. The transfer body 101 was fixed to the support member 102 using a double-sided adhesive tape. Using the reaction liquid application device 103, 1.0 g / m ² of the reaction liquid was applied onto the transfer body 101. As the ink applicator 104, a recording head of a type that ejects ink by an on-demand system including an electro-thermal conversion element was used.

The recording medium feeding roller 107a and the recording medium take-up roller 107b are driven so that the recording medium 108 is conveyed so that the moving speed of the transfer body 101 is equal to the moving speed. The recording medium 108 and the ink image were brought into contact between the transfer body 101 and the pressing member 106, and the ink image was transferred from the transfer body 101 to the recording medium 108 to record a solid image. As the recording medium 108, coated paper (trade name “Aurora Coated Paper”, manufactured by Nippon Paper Industries Co., Ltd., basis weight 104 g / m ² ) was used. The nip pressure between the transfer body 101 and the pressing member 106 was adjusted to 3 kg / cm ² .

(Clear white)
The recorded solid image was confirmed visually and with a magnifying glass having a magnification of 5 times, and white spots of the image were evaluated according to the following evaluation criteria.
A: White spots confirmed with a loupe did not occur.
B: White spots confirmed with a loupe occurred, but white spots confirmed visually did not occur.
C: The white spot confirmed visually was produced.

(Abrasion resistance)
The recorded solid image was cut to prepare two strip-shaped test pieces having a width of 25 mm. The produced strip-shaped test piece was placed on a scraper of a Gakushin type tester (abrasion resistance tester, manufactured by Imoto Seisakusho), and a friction test was performed 10 times with a load of 500 g. The strip-shaped test piece after the abrasion test was confirmed visually and with a magnifying glass having a magnification of 5 times, and the scratch resistance of the image was evaluated according to the following evaluation criteria.
A: The scratches confirmed with a loupe were not generated.
B: Although rubbing traces confirmed with a loupe were generated, no rubbing traces visually confirmed.
C: Scratch marks confirmed visually were generated.

  For Examples 31 and 32, the images were evaluated for scratch resistance by applying a load stronger than the conditions in the above evaluation of “scratch resistance”. As a result, it was found that Example 31 was relatively superior in image scratch resistance compared to Example 32. Further, in Examples 1 and 33 as well, the image was evaluated for scratch resistance by applying a load stronger than the condition in the evaluation of “scratch resistance”. As a result, it was found that the scratch resistance of the image in Example 1 is relatively superior to that in Example 33.

Claims (10)

A set of an ink and a reaction liquid, comprising a combination of an aqueous ink containing a pigment and an aqueous reaction liquid that reacts with the ink,
The reaction solution contains a reaction agent, resin particles formed of a polyolefin resin, and a fluorosurfactant,
A set of an ink and a reaction liquid, wherein the reactive agent is a hydroxy acid.   The ink and reaction liquid set according to claim 1, wherein the content (% by mass) of the hydroxy acid in the reaction liquid is 12.0% by mass or more based on the total mass of the reaction liquid.   The ink and reaction liquid set according to claim 1 or 2, wherein the content (mass%) of the resin particles in the reaction liquid is 5.0 mass% or more based on the total mass of the reaction liquid.   The content (mass%) of the hydroxy acid in the reaction solution is 1.0 to 8.0 times in mass ratio to the content (mass%) of the resin particles. A set of the ink and the reaction liquid according to any one of the above.   The content (mass%) of the resin particles in the reaction solution is 1.0 to 12.0 times in mass ratio with respect to the content (mass%) of the fluorosurfactant. The set of the ink and reaction liquid of any one of thru | or 4.   The ink and reaction liquid set according to any one of claims 1 to 5, wherein a 50% particle diameter (D50) based on a volume distribution of the resin particles is 20 nm or more and 200 nm or less.   The ink and reaction liquid set according to any one of claims 1 to 6, wherein the resin particles are emulsified with a nonionic emulsifier.   The set of the ink and the reaction liquid according to claim 1, wherein the polyolefin resin is a polyethylene resin.   The ink and reaction liquid set according to any one of claims 1 to 8, wherein the fluorosurfactant is a nonionic fluorosurfactant. An ink jet recording method for recording an image on a recording medium by bringing an ink and a reaction liquid into contact with each other,
An ink jet recording method, wherein the ink and the reaction liquid set according to claim 1 are used as the ink and the reaction liquid.

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