JP2023013189A - Gloss processing device and ink jet recording method - Google Patents

Abstract

To provide a gloss processing device which can perform gloss processing on an ink-jet-printed gloss coat sheet.SOLUTION: A gloss processing device comprises: a first pressing member 64 which is brought into contact with an ink film and heats the ink film to flatten the ink film for an ink jet printed matter P' formed with the ink film containing a color material and a thermoplastic resin component; and a second pressing member 63 which is arranged so as to oppose the first pressing member and form a nip part Q that passes and presses a recording medium between the first pressing member and itself. Regarding a loss tangent tanδ expressed by a ratio (E"/E') of a loss elastic modulus E" to a storage elastic modulus E', when the loss tangent of a surface material of the first pressing member at a heating temperature in the nip part is defined to be tanδA, the loss tangent of the recording medium at the same temperature is defined to be tanδB, and the loss tangent of a surface material of the second pressing member at the same temperature is defined to be tanδC, gloss processing can be effectively performed by satisfying a relation shown by the following formula (1): tanδA<tanδB<tanδC (1).SELECTED DRAWING: Figure 4

Description

The present invention relates to a gloss processing apparatus for performing gloss processing on inkjet recorded matter. The present invention also relates to an inkjet recording method including a step of applying a gloss treatment to an inkjet recorded matter.

As a gloss processing device, a heating belt is brought into close contact with the toner layer in the electrophotographic image forming method and pressurized to soften and smooth the toner. (Patent Document 1).

JP 2013-109288 A

Recording media for inkjet recording include gloss coated paper with a coating layer having a roughness (Rz) of about 10 μm or less, matte coated paper with a coating layer having an Rz of about 20 μm, and substrates without a coating layer. There are non-coated papers that retain the texture of the fiber surface of the paper.
Inkjet recording on glossy paper, such as gloss-coated paper, which has relatively small unevenness on the surface, may cause the printed portion to appear matte due to the unevenness caused by the traces of the deposited dots.
It has been found that even if the same gloss treatment as in Patent Document 1 is applied to gloss coated paper printed by inkjet printing, sufficient gloss cannot be obtained due to the thin film thickness in the step of applying heat and pressure. This is because in electrophotographic printing, the particle size of the toner is several μm, and the thickness of the formed toner film is 10 μm or more. Therefore, even on a recording medium having unevenness on the surface, a toner film sufficient to fill the recesses is interposed, and gloss can be imparted by the gloss treatment of Patent Document 1. In ink jet recording, ink containing thermoplastic fine particles is ejected from a nozzle for printing, and therefore the thermoplastic fine particles used are 1 μm or less, especially fine particles on the order of submicrons. Therefore, it is difficult to thicken the toner film, and even if it is attempted to thicken the film by overprinting, it is not practical because the throughput and the recording head portion are enlarged.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a gloss treatment apparatus capable of effectively applying gloss treatment to ink jet recorded matter in which an ink film is formed on a recording medium having an uneven surface such as gloss coated paper. is. Another object of the present invention is to provide an ink jet recording method capable of effective gloss processing.

According to one aspect of the invention,
A glossing treatment apparatus for applying a glossing treatment to an inkjet recorded matter in which an ink film containing a coloring material and a thermoplastic resin component is formed on a recording medium, the first glossing treatment device for flattening the ink film by heating it in contact with the ink film. a pressing member, a second pressing member facing the first pressing member and disposed so as to form a nip between the pressing member and the first pressing member for passing and pressing the inkjet recorded matter; with
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. Provided is a gloss processor characterized by satisfying the relationship:
tan δ _A < tan δ _B < tan δ _C (1).

Further, according to one aspect of the present invention, a step of ejecting an ink containing a coloring material and a thermoplastic resin component onto a recording medium by an inkjet method to form an inkjet recorded matter having an ink film;
The inkjet recorded matter is passed through and pressed against a nip formed by a first pressing member that is in contact with and heats the ink film, and a second pressing member that is arranged to face the first pressing member. a gloss treatment step of flattening the ink film by
An inkjet recording method having
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. An inkjet recording method is provided, characterized in that the surface material of the first pressing member and the surface material of the second pressing member are selected to satisfy the relationship:
tan δ _A < tan δ _B < tan δ _C (1).

ADVANTAGE OF THE INVENTION According to one aspect of the present invention, it is possible to provide a gloss processing apparatus that can effectively perform gloss processing on inkjet recorded matter in which an ink film is formed on a recording medium such as gloss coated paper. Further, according to one aspect of the present invention, it is possible to provide an inkjet recording method that enables effective gloss processing.

1 is a schematic diagram of an inkjet recording apparatus according to an embodiment; FIG. 2 is a block diagram of a control system of the printing apparatus of FIG. 1; FIG. 2 is a block diagram of a control system of the printing apparatus of FIG. 1; FIG. 1 is a schematic diagram of a gloss processing device; FIG. (a) is a recording medium (printed matter) after inkjet printing, (b) is the printed matter and the endless belt in the nip portion of the gloss processing device, and (c) is a schematic cross-sectional view of the recorded matter after separation from the endless belt. be. FIG. 10 is an explanatory diagram of loss tangent tan δ in the material of each member of the gloss processing device;

An embodiment of an inkjet recording apparatus for manufacturing an inkjet recorded matter (hereinafter, also simply referred to as a recorded matter) according to the present invention will be described below with reference to the drawings. In each drawing, the X direction indicated by an arrow indicates the horizontal direction in which the recording apparatus is placed, the Y direction is the direction perpendicular to the paper surface, and the X direction and the Y direction are orthogonal to each other. The Z direction indicated by an arrow indicates the vertical direction of the placed state. In this specification, the recording medium P subjected to ink jet recording is referred to as a recorded matter P′, and the recording medium P subjected to a gloss treatment, which will be described later, is referred to as a printed matter P″.

FIG. 1 is a schematic diagram of an inkjet recording apparatus (also referred to as a recording system) 1 according to the embodiment. The recording system 1 is a sheet-fed inkjet recording apparatus that transfers an ink image onto a recording medium P via a transfer body 2 to manufacture a recorded matter P′. The recording system 1 has a recording device 1A and a conveying device 1B. In this embodiment, the X direction, Y direction, and Z direction indicate the width direction (full length direction), depth direction, and height direction of the recording system 1, respectively. The recording medium P is conveyed in the X direction.
"Recording" includes not only the formation of meaningful information such as characters and figures, but also the formation of images, patterns, patterns, etc. on recording media, or the processing of media, regardless of significance or insignificance. The case is also included, regardless of whether or not it is materialized so that humans can perceive it visually. Also, the "recording medium" in this embodiment may be not only a sheet of paper but also cloth, plastic film, or the like. In particular, a glossy recording medium such as gloss coated paper is preferable.

<Recording device>
The recording apparatus 1A includes a recording unit 3, a transfer unit 4, peripheral units 5A to 5D, and an ink supply unit 6. FIG.

<Recording unit>
The recording unit 3 includes multiple recording heads 30 and a carriage 31 . The recording head 30 ejects liquid ink onto the transfer body 2 to form an ink image of a recording image on the transfer body 2 .
In this embodiment, each recording head 30 is a full-line head extending in the Y direction, and nozzles are arranged in a range covering the width of the image recording area of the maximum size recording medium that can be used. . The recording head 30 has an ink discharge surface with nozzles on its lower surface, and the ink discharge surface faces the surface of the transfer body 2 with a minute gap (for example, several millimeters) therebetween. In the case of this embodiment, the transfer body 2 is configured to cyclically move on a circular orbit, so the plurality of recording heads 30 are arranged radially.
Each nozzle is provided with an ejection element. The ejecting element is, for example, an element that generates pressure in a nozzle to eject ink in the nozzle, and a known inkjet head technology for an inkjet printer can be applied. Examples of ejection elements include an element that ejects ink by causing film boiling in ink by an electro-thermal converter to form air bubbles, an element that ejects ink by an electro-mechanical converter, and an element that ejects ink using static electricity. , and the like. From the viewpoint of high-speed and high-density recording, an ejection element using an electro-thermal converter is preferable.

In this embodiment, nine recording heads 30 are provided. Each recording head 30 ejects different types of ink. Different types of inks are, for example, inks with different coloring materials, such as yellow ink, magenta ink, cyan ink, and black ink. One recording head 30 normally ejects one type of ink, but one recording head 30 may be configured to eject a plurality of types of ink. When a plurality of recording heads 30 are provided in this manner, some of them may eject ink containing no coloring material (for example, clear ink).

A carriage 31 supports a plurality of printheads 30 . Each recording head 30 is fixed to a carriage 31 at the end on the side of the ink ejection surface. As a result, the gap between the ink ejection surface and the surface of the transfer body 2 can be maintained more precisely. The carriage 31 is configured to be displaceable while mounting the recording head 30 under the guidance of the guide member RL. In the case of this embodiment, the guide members RL are rail members extending in the Y direction, and are provided as a pair in the X direction, spaced apart from each other. A slide portion 32 is provided on each side portion of the carriage 31 in the X direction. The slide portion 32 engages with the guide member RL and slides along the guide member RL in the Y direction.

<Ink>
The ink applied to this embodiment contains a coloring material and a thermoplastic resin component. Each component of the ink will be described.
(colorant)
A pigment, a dye, or a mixture of a pigment and a dye can be used as a coloring material contained in the ink applied to this embodiment. The type of pigment that can be used as a coloring material is not particularly limited. Specific examples of pigments include inorganic pigments such as carbon black; and organic pigments such as azo-based, phthalocyanine-based, quinacridone-based, isoindolinone-based, imidazolone-based, diketopyrrolopyrrole-based, and dioxazine-based pigments. One or more of these pigments may be used as necessary.
The type of dye that can be used as the coloring material is not particularly limited. Specific examples of dyes include direct dyes, acid dyes, basic dyes, disperse dyes, and food dyes, and dyes having anionic groups can be used. Specific examples of dye skeletons include azo skeletons, triphenylmethane skeletons, phthalocyanine skeletons, azaphthalocyanine skeletons, xanthene skeletons, and anthrapyridone skeletons.
The content of the coloring material in the ink is not particularly limited as long as it is an amount capable of expressing a desired color tone, but is preferably 0.5% by mass or more and 15.0% by mass or less based on the total mass of the ink. It is preferably 1.0% by mass or more and 10.0% by mass or less.

(dispersant)
The ink may contain a dispersant for dispersing the pigment. As the dispersant, a known dispersant used for inkjet ink can be used. Among them, in one example of the present embodiment, it is preferable to use a water-soluble dispersant having both a hydrophilic portion and a hydrophobic portion in its structure. In particular, a pigment dispersant comprising a resin obtained by copolymerizing at least a hydrophilic monomer and a hydrophobic monomer is preferred. Each monomer used here is not particularly limited, and known monomers are preferably used. For example, hydrophobic monomers include styrene and other styrene derivatives, alkyl (meth)acrylates, benzyl (meth)acrylates, and the like. Examples of hydrophilic monomers include unsaturated carboxylic acids such as acrylic acid, methacrylic acid and maleic acid.
The acid value of the dispersant is preferably 50 mgKOH/g or more and 550 mgKOH/g or less. Moreover, the weight average molecular weight of the dispersant is preferably 1,000 or more and 50,000 or less. The mass ratio of pigment and dispersant (pigment:dispersant) is preferably in the range of 1:0.1 to 1:3.
In the present embodiment, it is also preferable to use a so-called self-dispersing pigment that is made dispersible by modifying the surface of the pigment itself without using a dispersant.

(Thermoplastic resin component)
The ink applied to this embodiment can be used by containing various resin fine particles that do not have a colorant as a thermoplastic resin component. Such fine resin particles are effective in improving image quality and fixability.
The material of the resin fine particles that can be used in this embodiment is not particularly limited, and known resins can be appropriately used. Specifically, homopolymers such as polyolefin, polystyrene, polyurethane, polyester, polyether, polyurea, polyamide, polyvinyl alcohol, poly(meth)acrylic acid and its salts, polyalkyl(meth)acrylate, and polydiene, or , and copolymers obtained by polymerizing a plurality of monomers for producing these homopolymers in combination. The weight average molecular weight (Mw) of these resins is preferably in the range of 1,000 or more and 2,000,000 or less. The amount of the fine resin particles in the ink is preferably 1% by mass or more and 50% by mass or less, more preferably 2% by mass or more and 40% by mass or less, relative to the total mass of the ink.
Furthermore, in one example of the present embodiment, it is preferable to use a resin fine particle dispersion in which resin fine particles are dispersed in a liquid. The method of dispersion is not particularly limited, but a so-called self-dispersing resin fine particle dispersion in which a resin obtained by homopolymerizing or copolymerizing a monomer having a dissociable group is used is suitable. Here, the dissociative group includes, for example, a carboxyl group, a sulfonic acid group, a phosphoric acid group, and the like, and the monomer having this dissociative group includes acrylic acid, methacrylic acid, and the like. Also, a so-called emulsified dispersion type resin fine particle dispersion, in which resin fine particles are dispersed with an emulsifier, can also be suitably used in the present embodiment. As the emulsifier referred to herein, a known surfactant is preferable regardless of whether it has a low molecular weight or a high molecular weight. As the surfactant, a nonionic surfactant or a surfactant having the same electric charge as that of the fine resin particles is preferred.
The fine resin particle dispersion used in the aspect of the present embodiment preferably has a dispersed particle size of 10 nm or more and 1000 nm or less, and more preferably has a dispersed particle size of 100 nm or more and 500 nm or less.
It is also preferable to add various additives for stabilization when preparing the fine resin particle dispersion used in the mode of the present embodiment. Examples of additives include n-hexadecane, dodecyl methacrylate, stearyl methacrylate, chlorobenzene, dodecyl mercaptan, blue dye (bluing agent), polymethyl methacrylate and the like.

(Surfactant)
The ink that can be used in this embodiment may contain a surfactant. Specific examples of surfactants include acetylene glycol ethylene oxide adducts (acetylenol E100, manufactured by Kawaken Fine Chemicals Co., Ltd.) and the like. The amount of surfactant in the ink is preferably 0.01% by mass or more and 5.0% by mass or less with respect to the total mass of the ink.

(Water and water-soluble organic solvent)
The ink used in this embodiment can contain water and/or a water-soluble organic solvent as a solvent. The water is preferably deionized water such as by ion exchange. Also, the content of water in the ink is preferably 30% by mass or more and 97% by mass or less with respect to the total mass of the ink.
The type of water-soluble organic solvent is not particularly limited, and known solvents can be used. Specifically, glycerin, diethylene glycol, polyethylene glycol, polypropylene glycol, ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, thiodiglycol, hexylene glycol, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, 2-pyrrolidone, ethanol. , methanol, and the like. Moreover, two or more kinds selected from these can be mixed and used.
The content of the water-soluble organic solvent in the ink is not particularly limited, but is preferably 3% by mass or more and 70% by mass or less with respect to the total mass of the ink.

(Other additives)
Ink that can be used in the present embodiment includes pH adjusters, rust inhibitors, preservatives, anti-mold agents, antioxidants, anti-reduction agents, water-soluble resins and their neutralizers, in addition to the above components, if necessary. It may contain various additives such as agents and viscosity modifiers.

<Transfer unit>
The transfer unit 4 will be described with reference to FIG. The transfer unit 4 includes a transfer cylinder 41 and an impression cylinder 42 . These cylinders are rotating bodies that rotate around a rotation axis in the Y direction, and have cylindrical outer peripheral surfaces. In FIG. 1, arc-shaped arrows shown in the figures of the transfer cylinder 41 and the impression cylinder 42 indicate their rotational directions, the transfer cylinder 41 rotating clockwise and the impression cylinder 42 rotating counterclockwise. do.
The transfer cylinder 41 is a support that supports the transfer body 2 on its outer peripheral surface. The transfer body 2 is provided on the outer peripheral surface of the transfer cylinder 41 continuously or intermittently in the circumferential direction. When provided continuously, the transfer member 2 is formed in an endless strip. On the other hand, when the transfer body 2 is provided intermittently, the transfer body 2 is divided into a plurality of segments in a belt-like shape with ends, and each segment can be arranged in an arc shape on the outer peripheral surface of the transfer cylinder 41 at equal pitches.
The rotation of the transfer cylinder 41 causes the transfer body 2 to cyclically move on a circular orbit. Depending on the rotational phase of the transfer cylinder 41, the position of the transfer body 2 can be classified into a pre-ejection processing region R1, an ejection region R2, post-ejection processing regions R3 and R4, a transfer region R5, and a post-transfer processing region R6. The transfer member 2 cyclically passes through these regions.

The pre-ejection treatment area R1 is an area in which pretreatment is performed on the transfer body 2 before ink is ejected by the recording unit 3, and is an area in which the peripheral unit 5A performs processing. In the case of this embodiment, a reaction liquid, which will be described later, is applied. The ejection area R2 is an area where the recording unit 3 ejects ink onto the transfer body 2 to form an ink image. The post-ejection processing regions R3 and R4 are processing regions in which the ink image is processed after the ink is ejected. The post-ejection processing region R3 is a region in which processing is performed by the peripheral unit 5B, and the post-ejection processing region R4 is a region in which processing is performed by the peripheral unit 5C. The transfer area R5 is an area where the ink image on the transfer body 2 is transferred to the recording medium P by the transfer unit 4. FIG. The post-transfer processing area R6 is an area where post-processing is performed on the transfer body 2 after transfer, and is an area where processing is performed by the peripheral unit 5D.
In the case of this embodiment, the ejection region R2 is a region having a certain section. The other regions R1, R3 to R6 are narrower than the ejection region R2. When compared to the dial of a clock, the pre-ejection treatment area R1 is approximately at the 10 o'clock position, the ejection area R2 is approximately in the range from 11 o'clock to 1 o'clock, and the post-ejection treatment area R3 is approximately at the 2 o'clock position. , the post-ejection treatment region R4 is approximately at the 4 o'clock position. The transfer region R5 is approximately at the 6 o'clock position, and the post-transfer processing region R6 is approximately at the 8 o'clock position.

The transfer member 2 may be composed of a single layer, or may be a laminate of multiple layers. When composed of multiple layers, it may include, for example, three layers of a surface layer, an elastic layer, and a compression layer. The surface layer is the outermost layer having an imaging surface on which an ink image is formed. By providing the compression layer, the compression layer absorbs deformation and disperses local pressure fluctuations, so that transferability can be maintained even during high-speed recording. The elastic layer is the layer between the surface layer and the compression layer.
Various materials such as resins and ceramics can be appropriately used as the material of the surface layer, and materials having a high compressive elastic modulus can be used in terms of durability. Examples of this material include acrylic resins, acrylic silicone resins, fluorine-containing resins, condensates obtained by condensing hydrolyzable organosilicon compounds, and the like. The surface layer may be subjected to a surface treatment in order to improve the wettability of the reaction liquid, the transferability of the image, and the like. Examples of surface treatment include flame treatment, corona treatment, plasma treatment, polishing treatment, roughening treatment, active energy ray irradiation treatment, ozone treatment, surfactant treatment, and silane coupling treatment. A plurality of these treatments may be combined. Also, the surface layer can be provided with an arbitrary surface shape.

Examples of materials for the compression layer include acrylonitrile-butadiene rubber, acrylic rubber, chloroprene rubber, urethane rubber, and silicone rubber. When molding such a rubber material, a predetermined amount of a vulcanizing agent, a vulcanization accelerator, etc. are blended, and a foaming agent, hollow fine particles, or a filler such as salt is blended as necessary to form a porous rubber material. may be As a result, the bubble portion is compressed with a change in volume in response to various pressure fluctuations, so deformation in directions other than the direction of compression is small, and more stable transferability and durability can be obtained. As porous rubber materials, there are continuous pore structures in which each pore is continuous with each other, and independent pore structures in which each pore is independent. You may
Various materials such as resins and ceramics can be appropriately used as the member of the elastic layer. Various elastomer materials and rubber materials can be used in terms of processability and the like. Examples thereof include fluorosilicone rubber, phenylsilicone rubber, fluororubber, chloroprene rubber, urethane rubber, and nitrile rubber. Also included are ethylene propylene rubber, natural rubber, styrene rubber, isoprene rubber, butadiene rubber, ethylene/propylene/butadiene copolymer, nitrile butadiene rubber and the like. In particular, silicone rubber, fluorosilicone rubber, and phenylsilicone rubber are preferable in terms of dimensional stability and durability because of their low compression set. In addition, the change in elastic modulus due to temperature is small, which is preferable in terms of transferability.
Various adhesives and double-sided tapes can be used between the surface layer and the elastic layer and between the elastic layer and the compression layer to fix them. In addition, the transfer body 2 may include a reinforcing layer having a high compression elastic modulus in order to suppress lateral stretching when mounted on the transfer cylinder 41 and to maintain stiffness. Moreover, it is good also considering a woven fabric as a reinforcement layer. The transfer member 2 can be produced by arbitrarily combining layers made of the above materials.

The impression cylinder 42 is pressed against the transfer body 2 at its outer peripheral surface. At least one grip mechanism for holding the leading edge of the recording medium P is provided on the outer peripheral surface of the impression cylinder 42 . A plurality of gripping mechanisms may be provided at intervals in the circumferential direction of the impression cylinder 42 . The recording medium P is transported in close contact with the outer peripheral surface of the impression cylinder 42, and when passing through the nip portion between the impression cylinder 42 and the transfer body 2, the ink image on the transfer body 2 is transferred.

<Peripheral unit>
Peripheral units 5A to 5D are arranged around the transfer cylinder 2. As shown in FIG. In this embodiment, the peripheral units 5A to 5D are, in order, the application unit 5A, the absorption unit 5B, the heating unit 5C, and the cleaning unit 5D.
The application unit 5A is a mechanism that applies a reaction liquid onto the transfer body 2 before the recording unit 3 ejects ink. The reaction liquid is a liquid containing a component that increases the viscosity of the ink. Here, increasing the viscosity of the ink means that the coloring materials, resins, etc. that make up the ink chemically react or physically adsorb when they come into contact with the components that increase the viscosity of the ink. An increase in ink viscosity is observed. This increase in the viscosity of the ink is not only when the viscosity of the ink as a whole increases, but also when the viscosity increases locally due to the aggregation of some of the components that make up the ink, such as colorants and resins. is also included.

The component that increases the viscosity of the ink is not particularly limited, and may be a metal ion, a polymer flocculant, or the like. However, a substance that causes a change in the pH of the ink to flocculate the coloring material in the ink, such as an organic acid, can be used. . Examples of the mechanism for applying the reaction liquid include a roller, a recording head, a die coating device (die coater), and a blade coating device (blade coater). If the reaction liquid is applied to the transfer body 2 before the ink is ejected onto the transfer body 2, the ink that reaches the transfer body 2 can be immediately fixed. As a result, bleeding in which adjacent inks are mixed can be suppressed.

The absorption unit 5B is a mechanism for absorbing liquid components from the ink image on the transfer body 2 before transfer. By reducing the liquid component of the ink image, bleeding of the image recorded on the recording medium P can be suppressed. If the reduction of the liquid component is explained from a different point of view, it can be expressed as concentrating the ink forming the ink image on the transfer body 2 . Concentrating the ink means that the liquid component contained in the ink is reduced, thereby increasing the content ratio of the solid content such as the coloring material and resin contained in the ink to the liquid component.
Absorption unit 5B includes a liquid absorption member that contacts the ink image to reduce the amount of the liquid component of the ink image. The liquid absorbing member may be formed on the outer peripheral surface of the roller, or the liquid absorbing member may be formed in the form of an endless sheet and run cyclically. In order to protect the ink image, the moving speed of the liquid absorbing member may be the same as the peripheral speed of the transfer member 2 so that the liquid absorbing member is moved in synchronization with the transfer member 2 .

The liquid absorbing member may include a porous body that contacts the ink image. In order to suppress adhesion of ink solids to the liquid absorbing member, the pore diameter of the porous body on the surface that contacts the ink image may be 10 μm or less. Here, the pore diameter refers to the average diameter, and can be measured by known means such as mercury porosimetry, nitrogen adsorption, SEM image observation, and the like. The liquid component is not particularly limited as long as it does not have a fixed shape, is fluid, and has a substantially constant volume. Examples of liquid components include water, organic solvents, and the like contained in ink and reaction liquids.

The heating unit 5C is a mechanism for heating the ink image on the transfer body 2 before transfer. By heating the ink image, the resin in the ink image is melted, and the transferability to the recording medium P is improved. The heating temperature can be the minimum film-forming temperature (MFT) of the resin or higher. MFT can be measured by a generally known technique, such as JIS K 6828-2:2003 or ISO2115:1996-compliant apparatus and method. From the viewpoint of transferability and image fastness, the heating may be at a temperature higher than that of the MFT by 10° C. or more, or further at a temperature higher than that of the MFT by 20° C. or more. The heating unit 5C can use a known heating device such as various lamps such as infrared rays, a hot air fan, and the like. In terms of heating efficiency, it is preferable to use an infrared heater.

The cleaning unit 5D is a mechanism for cleaning the transfer body 2 after transfer. The cleaning unit 5D removes ink remaining on the transfer body 2, dust on the transfer body 2, and the like. For the cleaning unit 5D, for example, a method of contacting the transfer body 2 with a porous member, a method of rubbing the surface of the transfer body 2 with a brush, a method of scraping the surface of the transfer body 2 with a blade, or the like can be appropriately used. can be done. Also, the cleaning member used for cleaning may have a known shape such as a roller shape or a web shape.

As described above, in this embodiment, the application unit 5A, the absorption unit 5B, the heating unit 5C, and the cleaning unit 5D are provided as peripheral units. Alternatively, a cooling unit may be added. In this embodiment, the temperature of the transfer body 2 may rise due to the heat of the heating unit 5C. After the ink is ejected onto the transfer body 2 by the recording unit 3, if the ink image exceeds the boiling point of water, which is the main solvent of the ink, the ability of the absorption unit 5B to absorb the liquid component may deteriorate. By cooling the transfer body 2 so that the ejected ink is maintained below the boiling point of water, it is possible to maintain the ability to absorb liquid components.

The cooling unit may be a blowing mechanism that blows air to the transfer body 2 or a mechanism that brings a member (for example, a roller) into contact with the transfer body 2 and cools the member by air cooling or water cooling. Alternatively, it may be a mechanism for cooling the cleaning member of the cleaning unit 5D. The cooling timing may be a period from after transfer to before application of the reaction liquid.

<Supply unit>
The supply unit 6 is a mechanism that supplies ink to each recording head 30 of the recording unit 3 . The supply unit 6 may be provided on the rear side of the recording system 1 . The supply unit 6 includes a storage section TK that stores ink for each type of ink. The storage section TK may be composed of a main tank and a sub-tank. Each reservoir TK and each recording head 30 are connected by a channel 6a, and ink is supplied to the recording head 30 from the reservoir TK. The channel 6a may be a channel for circulating ink between the reservoir TK and the recording head 30, and the supply unit 6 may include a pump or the like for circulating ink. A degassing mechanism for degassing air bubbles in the ink may be provided in the middle of the flow path 6a or in the reservoir TK. A valve for adjusting the liquid pressure of the ink and the atmospheric pressure may be provided in the middle of the flow path 6a or in the reservoir TK. The height of the reservoir TK and the recording head 30 in the Z direction may be designed such that the ink surface in the reservoir TK is lower than the ink ejection surface of the recording head 30 .

<Conveyor>
The conveying device 1B is a device that feeds the recording medium P to the transfer unit 4 and discharges from the transfer unit 4 the recording material P' onto which the ink image has been transferred. The transport device 1B includes a feed unit 7, a plurality of transport cylinders 8, 8a, two sprockets 8b, a chain 8c and a recovery unit 8d. In FIG. 1, the arrows inside the figures of the respective components of the conveying device 1B indicate the rotation directions of the components, and the arrows outside indicate the conveying path of the recording medium P or the printed matter P'. The recording medium P is conveyed from the feeding unit 7 to the transfer unit 4, and the recorded matter P' is conveyed from the transfer unit 4 to the recovery unit 8d. The side of the feeding unit 7 may be referred to as the upstream side in the transport direction, and the side of the collecting unit 8d may be referred to as the downstream side.
The feeding unit 7 includes a stacking section on which a plurality of recording media P are stacked, and also includes a feeding mechanism that feeds the recording media P one by one from the stacking section to the most upstream conveying cylinder 8 . Each transport cylinder 8, 8a is a rotating body that rotates around a rotation axis in the Y direction, and has a cylindrical outer peripheral surface. At least one gripping mechanism for holding the leading edge of the recording medium P (or the recorded matter P') is provided on the outer peripheral surface of each transport cylinder 8, 8a. Each gripping mechanism controls its gripping operation and release operation so that the recording medium P is transferred between adjacent transport cylinders.

The two transport cylinders 8a are transport cylinders for reversing the recording medium P. As shown in FIG. In the case of double-sided recording on the recording medium P, after transfer to the surface, the recording medium P is passed from the impression cylinder 42 to the transport cylinder 8a adjacent to the downstream side without being passed to the transport cylinder 8. FIG. The recording medium P is turned upside down via the two conveying cylinders 8a and transferred to the impression cylinder 42 again via the conveying cylinder 8 on the upstream side of the impression cylinder 42 . As a result, the back surface of the recording medium P faces the transfer cylinder 41, and the ink image is transferred to the back surface.
Chain 8c is wound between two sprockets 8b. One of the two sprockets 8b is a driving sprocket and the other is a driven sprocket. The rotation of the drive sprocket causes the chain 8c to circulate. The chain 8c is provided with a plurality of gripping mechanisms spaced apart in its longitudinal direction. The gripping mechanism grips the edge of the printed matter P'. The recorded material P′ is transferred from the conveying cylinder 8 located at the downstream end to the gripping mechanism of the chain 8c, and the recorded material P′ gripped by the gripping mechanism is transported to the collection unit 8d by the traveling of the chain 8c, and the gripping is released. be. As a result, the recorded matter P' is loaded in the collection unit 8d.

<Inspection unit>
The transport device 1B is provided with inspection units 9A and 9B. The inspection units 9A and 9B are arranged downstream of the transfer unit 4, and are mechanisms for inspecting the printed material P'.
In the case of this embodiment, the inspection unit 9A is a photographing device for photographing an image recorded on the recorded matter P', and includes, for example, an imaging device such as a CCD sensor or a CMOS sensor. The inspection unit 9A captures recorded images during the continuous recording operation. Based on the image photographed by the inspection unit 9A, it is possible to check the time-dependent change of the color tone of the recorded image and determine whether the image data or the recorded data can be corrected. In the case of this embodiment, the inspection unit 9A has an imaging range set on the outer peripheral surface of the impression cylinder 42, and is arranged so as to be able to partially photograph a recorded image immediately after transfer. All recorded images may be inspected by the inspection unit 9A, or may be inspected every predetermined number.

In the case of this embodiment, the inspection unit 9B is also a photographing device for photographing an image recorded on the recorded material P', and includes, for example, an imaging device such as a CCD sensor or a CMOS sensor. The inspection unit 9B takes a recorded image in the test recording operation. The inspection unit 9B captures the entire recorded image, and based on the image captured by the inspection unit 9B, can perform basic settings for various corrections related to the recorded data. In the case of this embodiment, it is arranged at a position for photographing the printed matter P' conveyed by the chain 8c. When the inspection unit 9B captures a recorded image, the running of the chain 8c is temporarily stopped and the whole is captured. The inspection unit 9B may be a scanner that scans the printed material P'.

<Control unit>
Next, the control unit of the recording system 1 will be explained. 2 and 3 are block diagrams of the control unit 13 of the recording system 1. FIG. The control unit 13 is communicatively connected to a host device (DFE) HC2, and the host device HC2 is communicably connected to the host device HC1.
The host device HC1 generates or stores document data that is the basis of a recorded image. The manuscript data here is generated, for example, in the form of an electronic file such as a document file or an image file. This document data is sent to the host device HC2, and the host device HC2 converts the received document data into a data format that can be used by the control unit 13 (for example, RGB data representing an image in RGB). The converted data is transmitted as image data from the host device HC2 to the control unit 13, and the control unit 13 starts recording operation based on the received image data.

In this embodiment, the control unit 13 is roughly divided into a main controller 13A and an engine controller 13B. The main controller 13A includes a processing unit 131, a storage unit 132, an operation unit 133, an image processing unit 134, a communication I/F (interface) 135, a buffer 136 and a communication I/F 137.
The processing unit 131 is a processor such as a CPU, executes programs stored in the storage unit 132, and controls the entire main controller 13A. The storage unit 132 is a storage device such as a RAM, a ROM, a hard disk, or an SSD, stores programs executed by the CPU 131 and data, and provides the CPU 131 with a work area. The operation unit 133 is, for example, an input device such as a touch panel, keyboard, or mouse, and receives user instructions.

The image processor 134 is, for example, an electronic circuit having an image processor. The buffer 136 is, for example, a storage device such as RAM, hard disk, or SSD. A communication I/F 135 communicates with the host device HC2, and a communication I/F 137 communicates with the engine controller 13B. Broken arrows in FIG. 2 illustrate the flow of image data processing. Image data received via communication I/F 135 from host device HC 2 is stored in buffer 136 . The image processing unit 134 reads the image data from the buffer 136 , performs predetermined image processing on the read image data, and stores the processed image data in the buffer 136 again. The image data after image processing stored in the buffer 136 is transmitted from the communication I/F 137 to the engine controller 13B as print data used by the print engine.

As shown in FIG. 3, the engine controller 13B includes a control section 15 (15A to 15F), acquires the detection results of the sensor group and the actuator group 16 provided in the recording system 1, and performs drive control. Each of these control units includes a processor such as a CPU, storage devices such as RAM and ROM, and interfaces with external devices. Note that the division of the control units is an example, and a part of the control may be executed by a plurality of subdivided control units. It may be configured to be performed by one control unit.

The engine control unit 15A controls the entire engine controller 13B. The recording control unit 15B converts the recording data received from the main controller 13A via the bus 14 into a data format suitable for driving the recording head 30, such as raster data. The recording control unit 15B controls ejection of each recording head 30. FIG.
The transfer control section 15C controls the application unit 5A, the absorption unit 5B, the heating unit 5C, and the cleaning unit 5D.
The reliability control section 15D controls the supply unit 6, the recovery unit 12, and the drive mechanism that moves the recording unit 3 between the ejection position POS1 and the recovery position POS3.
The transport controller 15E controls the transport device 1B. The inspection control section 15F controls the inspection unit 9B and the inspection unit 9A.
Among the sensor group and the actuator group 16, the sensor group includes a sensor for detecting the position and speed of the movable portion, a sensor for detecting temperature, an imaging device, and the like. The actuator group includes motors, electromagnetic solenoids, electromagnetic valves, and the like.

<Other embodiments>
Although the recording unit 3 has a plurality of recording heads 30 in the above embodiment, it may have a single recording head 30 . The recording head 30 may not be a full-line head, and may be of a serial type that forms an ink image while scanning the recording head 30 in the Y direction.
The transport mechanism for the recording medium P may be another system such as a system in which the recording medium P is nipped and transported by a pair of rollers. In the method of conveying the recording medium P by a pair of rollers, etc., a roll sheet may be used as the recording medium P, and the roll sheet may be cut after the transfer to produce the recorded matter P′.
In the above-described embodiment, the transfer body 2 is provided on the outer peripheral surface of the transfer cylinder 41, but other systems such as a system in which the transfer body 2 is formed in an endless strip and run cyclically may be used.

Further, the present invention supplies a program that implements one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in the computer of the system or apparatus reads and executes the program. It can also be realized by processing to It can also be implemented by a circuit (eg, an ASIC) that implements one or more functions.

<Gloss processing device>
A glossiness treatment device according to the present invention is a glossiness treatment device that performs glossiness treatment on an inkjet printed matter in which an ink film containing a coloring material and a thermoplastic resin component is formed on a recording medium, and is heated in contact with the ink film. and a first pressing member facing the first pressing member and arranged so as to form a nip portion between the first pressing member and the first pressing member for passing and pressing the recording medium. a second pressing member;
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. Characterized by satisfying the relation:
tan δ _A < tan δ _B < tan δ _C (1).

FIG. 4 shows a schematic diagram of a gloss processing apparatus according to one embodiment of the present invention. The recorded matter P′ printed on at least the upper side in the Z direction by the recording device 1A and the conveying device 1B described in FIG. . In this embodiment, an endless belt 64 stretched between a heating roller 61 and a support roller 62 is used as the first pressing member. The heating roller 61 has a heat source (not shown) and heats the endless belt 64 in contact with the ink film of the printed matter P' to a predetermined temperature. The heating roller 61 and the support roller 62 each have a rotatable structure, and the endless belt 64 can be moved (rotated) by providing a drive source (not shown) on at least one, preferably the heating roller 61 side. Further, a pressure roller 63 is further provided as a second pressure member, and a “nip portion” Q, which is a pressure contact range between the endless belt 64 and the pressure roller 63, is configured. The endless belt 64 is made of a metallic material, such as stainless steel, having a mirror-finished (glossy) outer peripheral surface. The pressure roller 63 is composed of at least two layers of a surface layer made of a surface material having heat resistance and elasticity on a substrate made of a metal material that is not distorted by stress during pressing. Select materials to fill.

Further, the gloss processing apparatus 60 according to the present invention is provided with a mechanism for cooling the recording medium heated at the nip portion Q downstream of the nip portion Q in the traveling direction of the recorded matter P′ (recording medium). can be done. Specifically, the cooling system consists of a cooling plate placed in contact with or very close to the inner surface of the endless belt 64, and a cooling system that circulates a coolant (e.g., water) from an external cooling chiller through piping provided in the cooling plate. A portion 65 may be provided. The cooling plate has a width equal to or greater than that of the endless belt, and can cool at least the entire image forming area of the recording medium to be passed. In addition, by arranging the cooling plate with a sufficient length in the conveying direction (X direction), the softened ink film is solidified, and the glossy print P″ can be separated from the endless belt 64.例文帳に追加However, the length is designed according to the heat exchange efficiency, the energy consumption of the chiller, and the device size.The cooling plate is fixed to the support walls (not shown) on both sides in the Y direction like the heating roller and the support roller. During operation or maintenance, it can be separated in the Z direction from the endless belt 64. By activating the cooling system and moving the endless belt 64, the portion contacting the heating roller 61 is After being heated, the endless belt is rapidly cooled to room temperature (about 25° C.) while it is moving and staying in the cooling section, whereby the recorded matter heated in the nip section Q is moved downstream in the traveling direction. The ink film 70 is cooled to a predetermined temperature while moving to the position of the supporting roller 62, and the ink film 70 becomes sufficiently hard to be peeled off due to the curvature of the endless belt. In addition to having a flat (mirror surface) shape with a roughness Ra of 60 nm or less, a release agent may be applied to prevent poor separation due to tackiness with a printed matter.

The auxiliary roller 66 is rotated so as to prevent the ink film 70 from peeling off or dropping before being sufficiently cooled in the process of flattening the ink film 70 along the flat outer surface of the endless belt 64 and curing. possible roller group. Since the temperature of the auxiliary roller 66 and the support roller 62 may rise due to heat radiation from the heated endless belt 64, it is more preferable that the temperature can be adjusted (cooled) like the cooling unit 65.
In the above embodiments, the endless belt is used as the first pressing member, and the pressing roller is used as the second pressing member. The combination of the first and second pressing members is not limited to this, and a combination of members rotatable with the movement of the recording medium, such as a belt-belt combination, can be used. In particular, it is preferable to sufficiently cool the surface of the first pressing member so that the surface state of the ink film does not change when the ink film after being pressed is peeled off from the first pressing member. The cooling section may also be omitted depending on the heating temperature, the solidification temperature of the ink film, the releasability of the recorded matter, etc., or other means such as air cooling with a fan or the like may be used.

<Gloss treatment>
FIG. 5 shows an image diagram of a cross section in the gloss treatment process of the inkjet recorded matter P' of this embodiment. Here, the structure of the recording medium will be explained using a coat paper having a two-layer structure of a base paper 71 and a coat layer 72 as an example. Gloss coated paper is used as the coated paper. Although only the recording surface is shown enlarged in FIG. 5, the double-sided coated paper has a similar coating layer on the opposite side of the base paper 71 to the coating layer 72, so that there are three layers. As shown in FIG. 5A, the ink film 70 fixed on the recording medium by ink jet recording is formed by laminating and fixing ink dots in a film shape, and the film thickness is a thin film of about 0.5 to 3 μm. .
FIG. 5(b) shows a state in which the endless belt 64 is in contact with the ink film 70 of the recorded matter P' in the nip portion Q and is heated and pressed. As shown in FIG. 4, when the endless belt 64 is stretched over the heating roller 61 and moves, heat is transferred from the inner side, and the outer side at the nip portion Q reaches a target temperature, for example, 100.degree. is set to The target temperature should be set to be equal to or higher than the softening temperature of the thermoplastic resin contained in the ink. The target temperature of the outer surface of the endless belt at the nip portion Q is set according to the viscoelasticity of each portion described below, and can be changed arbitrarily. At the nip portion Q, the outer surface of the endless belt 64 is in contact with the pressure roller 63 or the printed matter P′, so the temperature control was measured immediately after passing through the nip Q on the back side (pressure roller) side. Temperature was used as a proxy.
At the nip portion Q, the recorded matter P′ is in close contact with the endless belt 64 . At this time, the endless belt 64 is pressed from the inner side by the heating roller 61, and the printed material P' is pressed by the pressure roller 63 from below in the Z direction in FIG. At this nip portion Q, the surface material (stainless steel) of the endless belt 64 in contact with the ink film 70 is hard and smooth, so the ink film 70 is crushed and flattened along the outer surface of the endless belt 64. be. After that, the ink film 70 is cured by being conveyed to the cooling section 65 while the ink film 70 and the outer surface of the endless belt are in contact with each other. Finally, due to the curvature of the endless belt 64 by the support roller 62 and the hardness of the recording medium itself, the print P″ is peeled off and the surface is gloss-treated.
FIG. 5(c) is an image diagram of a cross section of printed matter P″ subjected to gloss treatment. The ink film 70 is flattened while almost maintaining the fine unevenness of the coat layer 72 of the recording medium. As a result, When printing on both sides of a recording medium, after one side is treated by the above method, the recording medium is turned upside down and the untreated ink film is treated in the same way. A well-known mechanism can be employed as the mechanism for reversing the recording medium.

Next, the loss tangent tan δ of the material will be explained. Using dynamic mechanical analysis (DMA) with a nanoindenter (Bruker, TI950), various viscoelasticities such as elastic modulus and viscous modulus are calculated from the stress applied to the sample and the detected strain (deformation). Amount is calculated. The ratio (E″/E′) of the storage modulus E′ and the loss modulus E″, which is the result of this measurement, is defined as the loss tangent (tan δ) and indicates the ratio of the viscous component to the elastic component of the sample. That is, it can be interpreted that the larger the tan δ, the more tenacious, and the smaller the tan δ, the less elastic.
FIG. 6 shows nano-scale materials for each member (ink film 70, coat layer 72, surface material (stainless steel) of the endless belt 64, and surface material (PFA or silicone rubber) of the pressure roller 63 related to gloss processing in this embodiment. The results of analysis using an indenter are shown for the coat layer 72. Aurora Coat (trade name, manufactured by Nippon Paper Industries Co., Ltd., basis weight: 157 g/m ² ), which is a type of gloss coated paper, is used for the coat layer 72, and values for coated paper are shown. A Berkovich type indenter was used, and the depth of indentation was set to 200 nm because the thickness of the ink film was as thin as 1 μm or less.The loss tangent due to the sample temperature (normal temperature = 25 ° C., high temperature = 100 ° C.) for each excitation frequency tan δ is plotted, where the excitation frequency corresponds to the reciprocal of the time (nip time) for passing through the nip portion Q in the gloss processing apparatus. When passing through a nip width of 20 mm, the nip time is 33 msec, and the excitation frequency corresponds to 30 Hz.In addition, 100° C. corresponds to the heating temperature at the nip portion.The heating temperature and nip time at the nip portion are as follows: The heating temperature is preferably 80° C. or higher, more preferably 90 to 120° C. The nip time is 10 to 120° C., and the heating temperature is preferably 80° C. or higher, more preferably 90 to 120° C. 300 msec is preferable, and 20 to 70 msec is more preferable.

It can be seen that the tan δ of the ink film 70 increases as the temperature rises from normal temperature to high viscosity. Also, the tan δ of the stainless steel material used for the endless belt is lower than that of the other samples regardless of the temperature and frequency, indicating that the belt is difficult to deform. When the vibration frequency is 300 Hz, the tan δ of the coated paper is larger than the tan δ of the ink film 70, which is not suitable for gloss processing.
On the other hand, in order to reliably transmit heat and pressure to the ink film at the nip portion Q, close contact between the pressure roller and the coated paper (back side of printing) is important. In this embodiment, during the period (nip time) in which the printed matter P′ stays in the nip portion Q between the heated endless belt 64 and the pressure roller 63, the upper and lower surfaces of the printed matter P′ are pressed by the respective members. need to adhere. Furthermore, the deformation of each material shown in FIG. 6 is determined by its viscoelasticity when heated in close contact. The nip time is determined by the curvature and deformation amount of the endless belt 64 and pressure roller 63 at the nip portion Q. FIG. Therefore, in order to lengthen the nip time (reduce the vibration frequency), it is effective to increase the diameter of the heating roller and to increase the amount of deformation (crushing) of the surface layer of the pressure roller 63 . However, both of them require an increase in equipment scale (size, power of cylinder, etc.), so they cannot be selected easily. Therefore, selection of an appropriate material based on the tan δ of each member will be considered.

In FIG. 6, the tan δ of PFA is smaller than the tan δ of the coat layer 72 at 30 Hz or higher, and the tan δ of the stainless steel material is smaller than any other material as described above. Therefore, when the PFA coating or stainless material is used for the pressure roller side, the coating layer side of the coated paper is deformed. That is, for gloss treatment with a nip time (33 msec or less) corresponding to 30 Hz or more, on the other hand, tan δ of silicone rubber is greater than tan δ of the coating layer at 3 Hz or more and 150 Hz or less. Therefore, when silicone rubber is used for the surface layer of the pressure roller 63 within the vibration frequency range, the surface layer of the pressure roller 63 is deformed, and thus deformation of the coat layer can be suppressed.
Actually, using the pressure roller 63 having a silicone rubber on the surface layer, gloss treatment was performed with a nip time of 33 msec and a heating temperature of 100° C. It was possible to improve compared with the case of using PFA. Note that the surface material of the pressure roller 63 in this embodiment is not limited to silicone rubber as long as it satisfies the formula (1).

Although the embodiments related to the apparatus have been described above, as is clear from the above description, the present invention also claims the following inkjet recording method as one aspect.
That is, a step of forming an inkjet recorded matter having an ink film by an inkjet method using an ink containing a coloring material and a thermoplastic resin component on a recording medium;
The inkjet recorded matter is passed through and pressed against a nip formed by a first pressing member that is in contact with and heats the ink film, and a second pressing member that is arranged to face the first pressing member. a gloss treatment step of flattening the ink film by
An inkjet recording method having
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. An inkjet recording method characterized by selecting the surface material of the first pressing member and the surface material of the second pressing member so as to satisfy the relationship:
tan δ _A < tan δ _B < tan δ _C (1).

The step of forming an inkjet recorded matter can be carried out by ejecting ink onto a transfer body to form an ink image using the inkjet recording apparatus described above, and then transferring the ink image onto a recording medium. be. However, it is not limited to that, and any conventionally known recording device may be used. For example, instead of the transfer type shown in FIG. 1, a direct drawing type ink jet recording method in which ink is directly ejected onto a recording medium to form an ink film may be used. Also, the recording medium and ink to be used can be those exemplified above.
Further, the gloss treatment process can be carried out using the gloss treatment apparatus described above. Any material can be used that can be safely selected in terms of

60 gloss processing device 63 pressure roller (second pressure member)
64 endless belt (first pressing member)
70 Ink film P Recording medium P' Ink jet recorded matter Q Nip part

Claims (10)

A gloss treatment apparatus for performing gloss treatment on an ink jet printed matter in which an ink film containing a coloring material and a thermoplastic resin component is formed on a recording medium, the first pressing for flattening by heating the ink film in contact with the ink film. and a second pressing member that faces the first pressing member and is arranged to form a nip between itself and the first pressing member for passing and pressing the recording medium. ,
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. A gloss processor characterized by satisfying the relationship:
tan δ _A < tan δ _B < tan δ _C (1). 2. The gloss processing apparatus according to claim 1, wherein said first pressing member and said second pressing member are a combination of members rotatable along with movement of said inkjet printed matter passing through said nip portion. wherein said first pressing member is an endless belt stretched between a heating roller and a supporting roller, and said second pressing member is a pressure roller having a surface layer of said surface material on a substrate; 3. The gloss processing device according to 1 or 2. 4. A gloss processing apparatus according to claim 3, wherein the surface material of said endless belt is stainless steel. 5. A gloss processing apparatus according to claim 3, wherein the surface material of said pressure roller is silicone rubber. 6. The gloss processing apparatus according to claim 1, wherein the recording medium has an uneven surface. 7. The gloss processing apparatus according to claim 1, further comprising a mechanism for cooling the recording medium heated in the nip portion downstream of the nip portion in the direction in which the recording medium advances. A step of forming an inkjet recorded matter having an ink film by an inkjet method using an ink containing a coloring material and a thermoplastic resin component on a recording medium;
The inkjet recorded matter is passed through and pressed against a nip formed by a first pressing member that is in contact with and heats the ink film, and a second pressing member that is arranged to face the first pressing member. a gloss treatment step of flattening the ink film by
An inkjet recording method having
Regarding the loss tangent tan δ represented by the ratio (E″/E′) of the storage elastic modulus E′ and the loss elastic modulus E″, the loss tangent of the surface material of the first pressing member at the heating temperature in the nip portion is When the loss tangent of the recording medium at the same temperature is tan δ _A , the loss tangent of the recording medium at the same temperature is tan δ _B , and the loss tangent of the surface material of the second pressing member at the same temperature is tan δ _C , the following formula (1) is obtained. An ink jet recording method characterized by selecting the surface material of the first pressing member and the surface material of the second pressing member so as to satisfy the relationship:
tan δ _A < tan δ _B < tan δ _C (1). 9. The inkjet recording method according to claim 8, wherein the step of forming the inkjet recorded matter is performed by ejecting the ink onto a transfer body to form an ink image, and then transferring the ink image onto a recording medium. 9. The inkjet recording method according to claim 8, wherein the step of forming the inkjet recorded matter comprises ejecting the ink onto a recording medium to form an ink film.

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