JP6849450B2 - Inkjet recording device and inkjet recording method - Google Patents

Description

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

In the inkjet recording method, an image is formed by directly or indirectly applying a liquid composition (ink) containing a coloring material onto a recording medium such as paper. At this time, curling or cockling may occur due to excessive absorption of the liquid component in the ink by the recording medium.
Therefore, in order to quickly remove the liquid component in the ink, the recording medium is dried by means such as warm air or infrared rays, or an image is formed on the transfer body and then included in the image on the transfer body. There is a method of transferring an image to a recording medium such as paper after the liquid component is dried by heat energy or the like.
Further, as a means for removing the liquid component contained in the image on the transfer body, a method in which a roller-shaped porous body is brought into contact with the ink image to absorb and remove the liquid component from the ink image without using thermal energy. Has been proposed (Patent Document 1).
Further, in a step of using a porous body as an absorber, removing a liquid from an ink image, and then sucking and recovering the liquid from the porous body by a pump or the like, another liquid is given to the absorber before the liquid is recovered. Therefore, a configuration for preventing the occurrence of air leakage has been proposed (Patent Document 2).

JP-A-2009-45551 JP-A-2007-268975

As disclosed in Patent Document 1, when the porous body having the liquid absorbing member is repeatedly used when removing the liquid from the ink image, the liquid absorbed inside the porous body becomes thickened. There is. In particular, when the reaction liquid for thickening the ink is used to promote the fixing of the ink image, the thickening of the liquid absorbed inside the porous body may become remarkable. When such thickening occurs, the flow resistance in the porous body when removing the liquid increases, and the necessary and sufficient liquid is absorbed within the time when the porous body is in contact with the ink image. Can not. As a result, it was found that a phenomenon (hereinafter referred to as "image flow") in which the liquid component in the ink image is swept away to the rear end side of the ink image by pressing by the liquid absorbing member occurs.
Patent Document 2 discloses that the efficiency of recovering the liquid from the porous body is improved by applying the liquid for preventing emptying, but the above-mentioned problem is caused by the thickening of the liquid component inside the porous body. There is no description or suggestion as to what may occur.
The present invention has been made in view of such a background technique. An object of the present invention is an inkjet recording apparatus and an inkjet recording method capable of suppressing image flow and forming a high-quality image even when a porous body is repeatedly used to absorb a liquid component from a formed image. Is to provide.

One aspect of the inkjet recording apparatus according to the present invention is
To the recording medium, an ink containing a water-soluble liquid medium and the coloring material, and applying a reaction liquid for thickening the ink reacts with the ink, first image containing an aqueous liquid component and the colorant And the image forming unit that forms
From the first image, a liquid absorbing member having a porous body that absorbs at least a part of the aqueous liquid component,
It is an inkjet recording device equipped with
A transport unit that repeatedly carries in and out of the liquid absorption member into and out of the liquid absorption treatment region where the liquid absorption treatment from the first image is performed by the liquid absorption member.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
A recovery liquid application control unit that intermittently applies the recovery liquid to the liquid absorption member by the recovery liquid application unit, and a recovery liquid application control unit.
It is characterized by having.
Another aspect of the inkjet recording apparatus according to the present invention is
Formed on the recording medium, an ink containing a water-soluble liquid medium and the coloring material reacts with the ink to impart a reaction liquid for thickening the ink, an ink image comprising the aqueous liquid component and a colorant Image formation unit and
A liquid absorbing member having a porous body that concentrates the ink constituting the ink image by absorbing at least a part of the aqueous liquid component from the ink image.
It is an inkjet recording device equipped with
A transport unit that repeatedly carries in and out of the liquid absorbing member into and out of the liquid absorbing processing region where the liquid absorbing treatment from the ink image by the liquid absorbing member is performed.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
A recovery liquid application control unit that intermittently applies the recovery liquid to the liquid absorption member by the recovery liquid application unit, and a recovery liquid application control unit.
It is characterized by having.
Another aspect of the inkjet recording apparatus according to the present invention is
An ink containing an aqueous liquid medium and a coloring material and a reaction liquid for reacting with the ink to thicken the ink are applied to a recording body, and a first image containing the aqueous liquid component and the coloring material is obtained. The image forming unit to be formed and
From the first image, a liquid absorbing member having a porous body that absorbs at least a part of the aqueous liquid component,
With
The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. An inkjet recording apparatus in which the second image above is transferred to a recording medium for forming a final image.
A transport unit that repeatedly carries in and out of the liquid absorption member into and out of the liquid absorption treatment region where the liquid absorption treatment from the first image is performed by the liquid absorption member.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
A recovery liquid application control unit that controls whether or not the recovery liquid is applied to the liquid absorption member by the recovery liquid application unit.
It is characterized by having.

Moreover, one aspect of the inkjet recording method according to the present invention is
To the recording medium, an ink containing a water-soluble liquid medium and the coloring material, by applying a reaction liquid for thickening the ink reacts with the ink, first comprising an aqueous liquid component and the colorant Image formation process to form an image and
A liquid absorption treatment in which the first surface of the porous body of the liquid absorbing member is brought into contact with the first image, and at least a part of the aqueous liquid component is absorbed by the porous body from the first image. In the liquid absorption process, which is performed in the liquid absorption treatment area,
It is an inkjet recording method having
A transfer step of retransmitting the porous body carried out from the liquid absorption treatment region to the liquid absorption treatment region, and
A recovery liquid application step of applying a recovery liquid having a viscosity lower than that of the ink and the reaction liquid to the first surface of the porous body before retransmission in the recovery liquid application unit.
Have a,
The porous body is repeatedly used for the liquid absorption treatment in the liquid absorption step, and the recovery liquid application step is intermittently performed with respect to the repeated use of the porous body .
Another aspect of the inkjet recording method according to the present invention is
A first image containing an aqueous liquid component and a coloring material by imparting an ink containing an aqueous liquid medium and a coloring material to a recording object and a reaction liquid for reacting with the ink to thicken the ink. And the image formation process to form
A liquid absorption treatment in which the first surface of the porous body of the liquid absorbing member is brought into contact with the first image, and at least a part of the aqueous liquid component is absorbed by the porous body from the first image. In the liquid absorption process, which is performed in the liquid absorption treatment area,
Have,
The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. An inkjet recording method in which the second image above is transferred to a recording medium for forming the final image.
A transfer step of retransmitting the porous body carried out from the liquid absorption treatment region to the liquid absorption treatment region, and
A recovery liquid application step of applying a recovery liquid having a viscosity lower than that of the ink and the reaction liquid to the first surface of the porous body before retransmission in the recovery liquid application unit.
A recovery liquid application control step for controlling the presence or absence of application of the recovery liquid to the porous body in the recovery liquid application unit, and a recovery liquid application control step.
It is characterized by having.

According to the present invention, an inkjet recording apparatus and an inkjet recording method that suppress image flow and enable high-quality image formation even when a porous body is repeatedly used to absorb a liquid component from a formed image. Can be provided.

It is a schematic diagram which shows an example of the structure of the transfer type inkjet recording apparatus 1 in this invention. It is a schematic diagram which shows an example of the structure of the transfer type inkjet recording apparatus 2 in this invention. It is a schematic diagram which shows an example of the structure of the transfer type inkjet recording apparatus 3 in this invention. It is a schematic diagram which shows an example of the structure of the direct drawing type inkjet recording apparatus in this invention. It is a block diagram which shows the control system of the whole apparatus in the inkjet recording apparatus shown in FIGS. 1 to 4. It is a block diagram of the printer control part in the transfer type inkjet recording apparatus shown in FIG. It is a block diagram of the printer control part in the direct drawing type inkjet recording apparatus shown in FIG.

In the inkjet recording method according to the present embodiment, a reaction liquid for thickening ink for promoting fixing of a coloring material and an ink containing an aqueous liquid medium and a coloring material are applied to a recording object to obtain an aqueous liquid component. It has an image forming step of forming a first image including the coloring material, and a liquid absorbing step of performing a liquid absorbing treatment of absorbing at least a part of an aqueous liquid component from the first image by a liquid absorbing member. The coloring material is applied to the recording object by an inkjet method.
The liquid absorbing member has a porous body that absorbs an aqueous liquid component, and the porous body has a first surface as a contact surface that comes into contact with the first image. At least a part of the aqueous liquid component contained in the first image is absorbed by the porous body through the first surface of the porous body.
The liquid absorption treatment is performed in a liquid absorption treatment region that enables contact between the porous body of the liquid absorption member and the first image.
The inkjet recording method according to the present embodiment has a transfer step of retransmitting the porous body carried out from the liquid absorption processing region to the liquid absorption region, and a recovery liquid applying portion on the first surface of the porous body before retransmission. It further has a recovery liquid applying step of applying a recovery liquid having a viscosity lower than that of the reaction liquid and the ink.

The inkjet recording apparatus used in the inkjet recording method according to the present embodiment absorbs an image forming unit that forms a first image containing an aqueous liquid component and a coloring material, and at least a part of the aqueous liquid component from the first image. It has a liquid absorbing member having a porous body to be formed.
The image forming unit has a reaction liquid applying unit for applying a reaction liquid for thickening ink for promoting fixing of a coloring material, and an inkjet recording unit for applying an aqueous liquid medium and an ink containing a coloring material.
The liquid absorption treatment from the first image by the liquid absorption member is performed in the liquid absorption treatment region, and is arranged so that the liquid absorption member and the first image can come into contact with each other in the liquid absorption treatment region. The liquid absorbing member is carried in, carried out, and retransmitted into the liquid absorption processing region by the transport unit, and a recovery liquid applying portion for applying the recovery liquid to the porous body of the liquid absorbing member before the retransmission is further provided.

The inkjet recording method according to the present embodiment further includes a wetting liquid applying step of applying a wetting liquid having a contact angle of less than 90 ° to the first surface of the porous body to the first surface of the porous body, and wets the porous body. It is possible to further have a liquid absorption step of performing the liquid absorption treatment through the first surface of the porous body to which the liquid is applied. The wetting treatment of the first surface of the porous body can be performed by at least one of the following methods.
(1) A method of accommodating a wetting liquid in an accommodating portion and supplying the wetting liquid from the accommodating portion to the first surface of the porous body to perform a wetting treatment.
(2) A method in which an aqueous liquid component contained in an image to be processed has a function as a wetting liquid, so that the wetting treatment is performed by contacting the first surface of the porous body with the first image.
The recovery liquid applying step also serves as a wetting liquid applying step, that is, these can be made the same step.

In addition to the above-described configuration, the inkjet recording apparatus applicable to the inkjet recording method according to the present embodiment using the wetting liquid uses a wetting liquid having a contact angle of less than 90 ° with respect to the first surface of the porous body. It has a wet treatment portion that is applied to the first surface of the porous body to perform a wet treatment.
As the structure of the wet treatment section, at least one of the following structures can be used.
(A) A configuration having an accommodating portion for accommodating the wetting liquid and a wetting liquid applying portion for supplying and applying the wetting liquid to the first surface of the porous body from the accommodating portion.
(B) The aqueous liquid component contained in the first image is provided with a function as a wetting liquid so that the first surface of the porous body in contact with the first image is wetted with the first liquid. In addition, the region where the first image of the recorded object is formed also serves as the wetting treatment section.

According to the present invention, by bringing the porous body of the liquid absorbing member into contact with the first image containing the aqueous liquid component and the coloring material on the recorded object, at least a part of the aqueous liquid component is obtained from the first image. Is removed. As a result, curling and cockling due to excessive absorption of the aqueous liquid component in the first image by a recording medium such as paper are suppressed.
Further, even when the porous body is repeatedly used for the absorption treatment of the liquid component from the first image formed by using the reaction solution and the ink, the recovery solution having a viscosity lower than that of the ink and the reaction solution is used before reuse. By applying it to the porous body, it is possible to suppress the thickening of the liquid absorbed in the porous body. As a result, it is possible to prevent image flow and form an image with high image quality.

In the inkjet recording apparatus according to the present embodiment, the image forming unit is not particularly limited as long as it can form a first image containing an aqueous liquid component and a coloring material on a recording object. The first image refers to an ink image before liquid removal before being subjected to liquid absorption treatment by a liquid absorbing member. Further, the ink image after liquid removal in which the content of the first liquid is reduced by performing the liquid absorption treatment is also referred to as a second image.
The image forming unit preferably includes 1) an apparatus that constitutes a reaction liquid application unit that applies the reaction liquid onto the recording object, and 2) an inkjet that applies ink containing an aqueous liquid medium and a coloring material onto the recording object. It has an apparatus that constitutes a recording unit.
The first image as the liquid absorption processing target is formed by applying the reaction liquid and the ink to the recorded object so that they have at least overlapping regions. The reaction solution promotes and improves the fixability of the coloring material applied together with the ink on the object to be recorded. The promotion and improvement of the fixability of the color material is that the fluidity of the color material in the ink itself or in the ink is increased by the action of the reaction solution from the initial state in which the ink applied to the recording object has fluidity. It means that the ink is lowered, thickened compared to the initial state, and becomes a fixed state in which it is difficult to flow. The mechanism will be described later.
The first image is formed containing a mixture of reaction solution and ink. The ink contains an aqueous liquid medium containing water, and the reaction liquid also contains an aqueous liquid medium containing water, if necessary. The first image contains an aqueous liquid component, including water, supplied from these aqueous liquid media, along with a colorant.
An inkjet recording device is used as a device for applying ink onto the object to be recorded.
In addition, the reaction solution may contain a component that chemically or physically acts with the ink to make the mixture of the reaction solution and the ink more viscous than each of the reaction solution and the ink and improve the fixability of the coloring material. it can. The reaction solution can include an aqueous liquid medium. The aqueous liquid medium contains at least water and, if necessary, a water-soluble organic solvent and various additives.
At least one of the reaction solution and the ink can contain a second liquid other than that when water is used as the first liquid. The volatility of the second liquid does not matter, but it is preferably a liquid having a higher volatility than the first liquid.

Hereinafter, an embodiment of the present invention will be described.

<Reaction solution applying device>
The reaction solution applying device may be any device capable of applying the reaction solution onto the recorded object, and various conventionally known devices can be appropriately used. Specific examples thereof include a gravure offset roller, an inkjet head, a die coating device (die coater), and a blade coating device (blade coater). The reaction solution may be applied by the reaction solution application device before the ink is applied or after the ink is applied, as long as it can be mixed (reacted) with the ink on the recording object. Preferably, the reaction solution is applied before applying the ink. By applying the reaction solution before applying the ink, bleeding in which the adjacently applied inks are mixed with each other during image recording by the inkjet method, and bee in which the ink landed first is attracted to the ink landed later. Inking can be suppressed.

<Reaction solution>
The reaction solution contains a component that increases the viscosity of the ink (ink high viscosity component). Increasing the viscosity of ink means that coloring materials, resins, etc., which are part of the components 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. This means that an increase in ink viscosity is observed. This increase in viscosity of the ink is not limited to the case where an increase in the viscosity of the ink is observed, but also the case where a part of the components constituting the ink such as a coloring material or a resin aggregates to cause a local increase in the viscosity. included. As a method of agglutinating a part of the components constituting the ink, a reaction solution that lowers the dispersion stability of the pigment in the water-based ink can be used. This ink high viscosity component reduces the fluidity of the ink and / or some of the components constituting the ink on the recording object, and suppresses bleeding and beading during the first image formation. Has the effect of Increasing the viscosity of an ink is also referred to as "making the ink viscous." As such an ink high viscosity component, known substances such as polyvalent metal ions, organic acids, cationic polymers, and porous fine particles can be used. Of these, polyvalent metal ions and organic acids are particularly preferable. It is also preferable to contain a plurality of types of ink high viscosity components. The content of the ink high viscosity component in the reaction solution is preferably 5% by mass or more with respect to the total mass of the reaction solution.
Examples of the polyvalent metal ion include divalent metal ions ^{such as Ca 2+} , Cu ²⁺ , Ni ²⁺ , Mg ²⁺ , Sr ²⁺ , Ba ²⁺ and Zn ^{2+ , Fe 3+} , Cr ³⁺ , Y ³⁺ and Al ^3+, etc. Trivalent metal ions of.
Examples of organic acids include oxalic acid, polyacrylic acid, formic acid, acetic acid, propionic acid, glycolic acid, malonic acid, malonic acid, maleic acid, ascorbic acid, levulinic acid, succinic acid, glutaric acid, glutamic acid, and fumaric acid. , Citric acid, tartaric acid, lactic acid, pyrrolidone carboxylic acid, pyron carboxylic acid, pyrrol carboxylic acid, furan carboxylic acid, pyridine carboxylic acid, coumarin acid, thiophene carboxylic acid, nicotinic acid, oxysuccinic acid, dioxysuccinic acid and the like.
The reaction solution can contain an appropriate amount of water or a low volatility organic solvent as an aqueous liquid medium. The water used in this case is preferably water that has been deionized by ion exchange or the like. The organic solvent that can be used in the reaction solution applied to the present invention is not particularly limited, and a known organic solvent can be used.
Further, the reaction solution can be used by adding a surfactant or a viscosity modifier to appropriately adjust its surface tension and viscosity. The material used is not particularly limited as long as it can coexist with the ink high viscosity component. Specific examples of the surfactant used include acetylene glycol ethylene oxide adduct (product name: acetylenol E100, manufactured by Kawaken Fine Chemical Co., Ltd.), perfluoroalkylethylene oxide adduct (product name: Megafuck F444, manufactured by DIC Co., Ltd.). Product name: Capstone FS-3100, The Chemours Company LLC, Product name: ZonylFS3100, Dupont, etc.) Fluorine-based surfactant, polyether-modified polydimethylsiloxane adduct (Product name: BYK349, BYK) Examples include surfactants.
The aqueous liquid component obtained by allowing the reaction liquid to act on the ink can be used as the wetting liquid. In this case, the composition of the ink and / or the reaction solution is adjusted so that the contact angle of the mixture with respect to the first surface of the water-repellent porous body is less than 90 °. The contact angle of this mixture can be adjusted by selecting the type and amount of the surfactant to be added to the ink and / or the reaction solution.

<Ink application device>
An inkjet head is used as an ink applying device for applying ink. The inkjet head includes, for example, a form in which a film is boiled in the ink by an electric-heat converter to form bubbles to eject the ink, a form in which the ink is ejected by an electric-mechanical converter, and an ink jet head using static electricity. Examples thereof include a discharge form. In the present invention, a known inkjet head can be used. Among them, those using an electric-heat converter are preferably used from the viewpoint of high-speed and high-density printing. Drawing is performed by receiving an image signal and applying a required amount of ink to each position.
The amount of ink applied can be expressed by image density (duty) or ink thickness, but in this embodiment, the amount of ink applied is the average value obtained by multiplying the mass of each ink dot by the number of applied ink dots (number of ejected inks) and dividing by the print area. It was set to (g / m ² ). The maximum amount of ink applied in the image area is the amount of ink applied in an area of at least 5 mm ² or more in the area used as information of the recorded object from the viewpoint of removing the liquid component in the ink. Shown.
The inkjet recording apparatus of the present invention may have a plurality of inkjet heads in order to apply ink of each color on the recording object. For example, when forming each color image using yellow ink, magenta ink, cyan ink, and black ink, the inkjet recording apparatus has four inkjet heads for ejecting the above four types of ink onto the recording object.
Further, the ink applying device may include an inkjet head that ejects ink (clear ink) that does not contain a coloring material.

Each component of the ink applied to the present invention will be described.
(Color material)
As the coloring material contained in the ink applied to the present invention, a pigment or a mixture of a dye and a pigment can be used. The type of pigment that can be used as a coloring material is not particularly limited. Specific examples of the pigment 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. As these pigments, one kind or two or more kinds can be used as needed.
The type of dye that can be used as a coloring material is not particularly limited. Specific examples of the dye include a direct dye, an acid dye, a basic dye, a disperse dye, an edible dye, and the like, and a dye having an anionic group can be used. Specific examples of the dye skeleton include an azo skeleton, a triphenylmethane skeleton, a phthalocyanine skeleton, an azaphthalocyanine skeleton, a xanthene skeleton, an anthrapyridone skeleton and the like.
The content of the pigment in the ink is preferably 0.5% by mass or more and 15.0% by mass or less, and more preferably 1.0% by mass or more and 10.0% by mass or less with respect to the total mass of the ink. ..

(Dispersant)
As the dispersant for dispersing the pigment, a known dispersant used for ink jet ink can be used. Above all, in the aspect of the present invention, it is preferable to use a water-soluble dispersant having both a hydrophilic part and a water-repellent part in the structure. In particular, a pigment dispersant composed of a resin obtained by copolymerizing at least a hydrophilic monomer and a water-repellent monomer is preferably used. The monomer used here is not particularly limited, and known ones are preferably used. Specifically, examples of the water-repellent monomer include styrene and other styrene derivatives, alkyl (meth) acrylate, benzyl (meth) acrylate and the like. Examples of the hydrophilic monomer include acrylic acid, methacrylic acid, maleic acid and the like.
The acid value of the dispersant is preferably 50 mgKOH / g or more and 550 mgKOH / g or less. The weight average molecular weight of the dispersant is preferably 1000 or more and 50,000 or less. The mass ratio of the pigment to the dispersant (pigment: dispersant) is preferably in the range of 1: 0.1 to 1: 3.
It is also preferable to use a so-called self-dispersing pigment in which the pigment itself is surface-modified so that it can be dispersed without using a dispersant.

(Resin fine particles)
The ink applied to the present invention can be used by containing various fine particles having no coloring material. Among them, resin fine particles are preferable because they may be effective in improving image quality and fixability.
The material of the resin fine particles that can be used in the present invention is not particularly limited, and a known resin can be appropriately used. Specifically, copolymers of polyolefins, polystyrenes, polyurethanes, polyesters, polyethers, polyureas, polyamides, polyvinyl alcohols, poly (meth) acrylic acids and salts thereof, alkyl poly (meth) acrylates, polydiene and the like, or , Copolymers obtained by combining a plurality of monomers for producing these homopolymers and polymerizing them. The weight average molecular weight (Mw) of the resin is preferably in the range of 1,000 or more and 2,000,000 or less. The amount of the resin fine particles in the ink is preferably 1% by mass or more and 50% by mass or less, and more preferably 2% by mass or more and 40% by mass or less with respect to the total mass of the ink.
Further, in the aspect of the present invention, it is preferable to use it as a resin fine particle dispersion in which the 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 monomer having a dissociative group is dispersed using a resin obtained by homopolymerization or copolymerization of a plurality of types is preferable. Here, examples of the dissociative group include a carboxyl group, a sulfonic acid group, and a phosphoric acid group, and examples of the monomer having this dissociative group include acrylic acid and methacrylic acid. Further, a so-called emulsified dispersion type resin fine particle dispersion in which resin fine particles are dispersed by an emulsifier can also be preferably used in the present invention. As the emulsifier referred to here, a known surfactant is preferable regardless of the low molecular weight or the high molecular weight. The surfactant is preferably a nonionic surfactant or a surfactant having the same charge as the resin fine particles.
The resin fine particle dispersion used in the embodiment of the present invention preferably has a dispersed particle size of 10 nm or more and 1000 nm or less, more preferably has a dispersed particle size of 50 nm or more and 500 nm or less, and has a dispersed particle size of 100 nm or more and 500 nm or less. It is more preferable to have.
It is also preferable to add various additives for stabilization when producing the resin fine particle dispersion used in the embodiment of the present invention. Examples of the additive 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 the present invention may contain a surfactant. Specific examples of the surfactant include an acetylene glycol ethylene oxide adduct (product name: acetylenolol E100, manufactured by Kawaken Fine Chemicals Co., Ltd.) and the like. The amount of the 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.
As described earlier in the section on the reaction solution, the ink and / / so that the contact angle of the aqueous liquid component obtained by allowing the reaction solution to act on the ink with respect to the first surface of the porous body is less than 90 °. Alternatively, the composition of the reaction solution can be adjusted. The contact angle of this mixture can be adjusted by selecting the type and amount of the surfactant to be added to the ink and / or the reaction solution.

(Water and water-soluble organic solvent)
As the ink, a water-based ink containing at least water is used as the liquid medium. As the water-based ink, a water-based pigment ink containing at least a pigment as a coloring material can be used.
The liquid medium can further contain a water-soluble organic solvent, if desired. The water is preferably water that has been deionized by ion exchange or the like. The water content 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 used is not particularly limited, and any known organic solvent 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, etc. Of course, two or more kinds selected from these can be mixed and used.
The content of the water-soluble organic solvent in the ink is preferably 3% by mass or more and 70% by mass or less with respect to the total mass of the ink.

(Other additives)
In addition to the above components, the inks that can be used in the present invention include pH adjusters, rust inhibitors, preservatives, fungicides, antioxidants, antioxidants, water-soluble resins and their neutralizers, if necessary. , Various additives such as viscosity regulators may be contained.

<Liquid absorption member>
In the present invention, at least a part of the aqueous liquid component from the first image is absorbed by contacting with a liquid absorbing member having a porous body, and the content of the liquid component in the first image is reduced. The contact surface of the liquid absorbing member with the first image is set as the first surface, and the porous body is arranged on the first surface.

(Porous medium)
The porous body preferably has a small pore diameter in order to suppress the adhesion of the color material of the ink, and the pore diameter of the porous body on the side (first surface) in contact with at least the first image is 1 μm or less. Is preferable. In the present invention, the pore diameter indicates an average diameter, and can be measured by a known means such as a mercury intrusion method, a nitrogen adsorption method, SEM image observation, or the like.
Further, it is preferable to reduce the thickness of the porous body in order to uniformly obtain high air permeability. The air permeability can be indicated by a galley value defined by JIS P8117, and the galley value is preferably 10 seconds or less. The shape of the porous body is not particularly limited, and examples thereof include a roller shape and a belt shape.
However, if the porous body is made thin, it may not be possible to secure a sufficient capacity for absorbing the liquid component, so that the porous body can have a multi-layer structure. Further, the liquid absorbing member may have a porous body as long as the layer in contact with the image on the recorded body is porous, and the layer not in contact with the image on the recorded body may not be porous.
Further, there is no particular limitation on the manufacturing method of the porous body, and the manufacturing method widely used conventionally can be applied. As an example, a method for producing a porous body obtained by biaxially stretching a resin containing polytetrafluoroethylene described in Japanese Patent No. 1114828 can be mentioned.
In the present invention, the material for forming the porous body is not particularly limited, and both a hydrophilic material having a contact angle with water of less than 90 ° and a water-repellent material having a contact angle with water of 90 ° or more are used. can do.
In the case of a hydrophilic material, the contact angle with water is more preferably 40 ° or less. When the first layer is made of a hydrophilic material, it has the effect of sucking up aqueous liquid components, especially water, by capillary force.
Examples of the hydrophilic material include polyolefin (polyethylene (PE) and the like), polyurethane, nylon, polyamide, polyester (polyethylene terephthalate (PET) and the like), polysulfone (PSF) and the like.
The porous body preferably has water repellency in order to reduce the affinity with the coloring material contained in the first image. The water-repellent porous body preferably has a contact angle with pure water of 90 ° or more. As a result of diligent studies by the present inventors, it was found that by using a porous body having a contact angle with pure water of 90 ° or more, adhesion of the color material of the ink to the porous body can be suppressed. The contact angle in the present specification is an angle formed by dropping a measurement liquid onto an object and the tangent line between the surface of the object and the tangent line of the droplet at a portion where the droplet is in contact with the object. Although there are several types of measurement techniques, the present inventor measured water repellency according to the technique described in "6. Hydrostatic method" of JIS R3257.
The material of the water-repellent porous body is not particularly limited as long as the contact angle with pure water is 90 ° or more, but a water-repellent resin is preferable. Further, the water-repellent resin is preferably a fluororesin. Specific examples of the fluororesin include polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polyvinyl fluoride (PVF), perfluoroalkoxyfluororesin (PFA), and four. Examples thereof include ethylene fluoride / propylene hexafluoride copolymer (FEP), ethylene / ethylene tetrafluoroethylene copolymer (ETFE), and ethylene / chlorotrifluoroethylene copolymer (ECTFE). As these resins, one type or two or more types can be used as required, and a configuration in which a plurality of films are laminated may be used. Of these, polytetrafluoroethylene is preferable.

<Multi-layer configuration>
Next, an embodiment in the case where the porous body has a multi-layer structure will be described. Here, the first layer on the side in contact with the first image and the layer laminated on the surface opposite to the contact surface of the first layer with the first image will be described as the second layer. Further, the multi-layer structure is also described in the order of stacking from the first layer. In the present specification, the first layer may be referred to as an "absorption layer", and the second and subsequent layers may be referred to as a "support layer".

The first layer can be formed from the porous body described above in the section "(Porous body)".
It is preferable to use the above-mentioned water-repellent porous body for the first layer in order to suppress the adhesion of the coloring material and to improve the cleaning property. One type or two or more types of these resins can be used as required, and a plurality of films may be laminated in the first layer.
When the first layer is made of a water-repellent material, there is almost no effect of sucking up the water-based liquid component due to the capillary force, and it may take time to suck up the water-based liquid component at the first contact with the image. Therefore, it is preferable to impregnate the first layer with a wetting liquid having a contact angle with the first layer of less than 90 °.
The wetting liquid can be impregnated into the first layer by applying it to the first surface of the liquid absorbing member by a coating method or the like. The wetting liquid is preferably prepared by mixing a liquid medium containing water with a liquid having a low contact angle with a surfactant or the first layer. Since the wetting liquid impregnated in the porous material is gradually replaced by the aqueous liquid component absorbed from the first image, the absorption efficiency of the first layer may gradually decrease. Therefore, it is preferable to apply the wetting liquid to the first surface of the porous body of the liquid absorbing member by applying the wetting liquid every predetermined number of times.
Also, by adjusting the composition of the reaction solution and / or the ink so that the contact angle of the aqueous liquid component contained in the first image with respect to the first surface of the first layer is less than 90 °, this mixture is prepared. It can be used as a wetting liquid. In this case, the contact angle of the mixture can be adjusted by mixing the reaction liquid and / or the ink with a liquid having a low contact angle with respect to the first surface of the surfactant or the water-repellent porous body. it can.
In the present invention, the film thickness of the first layer is preferably 50 μm or less. The film thickness is more preferably 30 μm or less. In the examples of the present invention, the film thickness was obtained by measuring the film thickness at any 10 points with a straight-ahead micrometer OMV_25 (manufactured by Mitutoyo) and calculating the average value thereof.
The first layer can be produced by a known method for producing a thin film porous membrane. For example, it can be obtained by obtaining a sheet of resin material by a method such as extrusion molding and then stretching it to a predetermined thickness. Further, a porous film can be obtained by adding a plasticizer such as paraffin to the material at the time of extrusion molding and removing the plasticizer by heating or the like at the time of stretching. The pore size can be adjusted by appropriately adjusting the amount of the plasticizer to be added, the draw ratio, and the like.

[Second layer]
In the present invention, the second layer is preferably a breathable layer. Such a layer may be a non-woven fabric of resin fibers or a woven fabric. The material of the second layer is not particularly limited, but the contact angle between the first layer and the aqueous liquid component absorbed from the image is the same so that the liquid absorbed toward the first layer does not flow back. It is preferably a lower material. Specifically, a single material such as polyolefin (polyethylene (PE), polypropylene (PP), etc.), polyurethane, nylon, polyamide, polyester (polyethylene terephthalate (PET), etc.), polysulphon (PSF), or a single material thereof. It is preferably selected from composite materials and the like. Further, the second layer is preferably a layer having a larger pore diameter than the first layer.

[Third layer]
In the present invention, the porous body having a multi-layer structure may have a structure of three or more layers. As the third and subsequent layers (also referred to as the third layer), a non-woven fabric is preferable from the viewpoint of rigidity. As the material, the same material as the second layer is used.

[Other materials]
In addition to the above-mentioned porous body having a laminated structure, the liquid absorbing member may have a reinforcing member for reinforcing the side surface of the liquid absorbing member. Further, it may have a joining member for connecting the longitudinal end portions of a long sheet-shaped porous body to form a belt-shaped member. As such a material, a non-porous tape material or the like can be used, and it may be arranged at a position or a period that does not come into contact with the image.

[Manufacturing method of porous body]
The method of laminating the first layer and the second layer to form a porous body is not particularly limited. They may simply be layered or glued together using methods such as adhesive laminating or thermal laminating. From the viewpoint of breathability, thermal lamination is preferable in the present invention. Further, for example, a part of the first layer or the second layer may be melted by heating and adhered and laminated. Further, a fusion material such as hot melt powder may be interposed between the first layer and the second layer and adhered and laminated to each other by heating. When laminating the third layer or more, they may be laminated at once or sequentially, and the stacking order is appropriately selected.
In the heating step, a laminating method in which the porous body is heated by sandwiching the porous body with heated rollers and pressurizing the porous body is preferable.

Next, a specific embodiment of the inkjet recording apparatus of the present invention will be described.
The inkjet recording device of the present invention is an inkjet recording device that forms a first image on a transfer body as a recording body and transfers a second image after absorption of an aqueous liquid component by a liquid absorbing member to a recording medium. And an inkjet recording device that forms a first image on a recording medium as a recording object. In the present invention, the former inkjet recording device is hereinafter referred to as a transfer type inkjet recording device for convenience, and the latter inkjet recording device is hereinafter referred to as a direct drawing type inkjet recording device for convenience.
Each inkjet recording device will be described below.

(Transfer type inkjet recording device)
1 to 3 are schematic views showing an example of a schematic configuration of the transfer type inkjet recording devices 1 to 3 of the present embodiment, respectively.
The transfer-type inkjet recording devices 1 to 3 include a transfer body 101 that temporarily holds a first image and a second image obtained by absorbing and removing at least a part of an aqueous liquid component from the first image. .. Further, the transfer type inkjet recording devices 1 to 3 transfer the second image onto a recording medium such as paper on which the image should be formed, that is, a recording medium for forming a final image according to the intended use. A pressing member 106 for transfer is provided.
The transfer-type inkjet recording devices 1 to 3 are mounted on the transfer body 101 supported by the support member 102, the reaction solution applying device 103 for applying the reaction solution onto the transfer body 101, and the transfer body 101 to which the reaction solution is applied. The liquid is applied by pressing the ink applying device 104 that applies ink to form the first image on the transfer body, the liquid absorbing device 105 that absorbs the liquid component from the first image on the transfer body, and the recording medium 108. It has a transfer pressing member 106 for transferring a second image on a transfer body from which components have been removed onto a recording medium 108 such as paper. Further, the transfer type inkjet recording devices 1 to 3 may have a transfer body cleaning member 109 that cleans the surface of the transfer body 101 after transferring the second image to the recording medium 108.
The support member 102 rotates about the rotation shaft 102a in the direction of the arrow in FIG. The transfer body 101 is moved by the rotation of the support member 102. The reaction solution by the reaction solution applying device 103 and the ink by the ink applying device 104 are sequentially applied onto the transferred body 101 to be moved, and the first image is formed on the transfer body 101. The first image formed on the transfer body 101 is moved to a position where the transfer body 101 comes into contact with the liquid absorption member 105a included in the liquid absorption device 105. The liquid absorbing member 105a of the liquid absorbing device 105 moves in synchronization with the rotation of the transfer body 101. The first image formed on the transfer body 101 goes through a state of being in contact with the moving liquid absorbing member 105a. During this time, the liquid absorbing member 105a removes the liquid component including at least the aqueous liquid component from the first image. By passing through the state of being in contact with the liquid absorbing member 105a, the liquid component contained in the first image is removed. In this contacted state, it is preferable that the liquid absorbing member 105a is pressed against the first image with a predetermined pressing force from the viewpoint of effectively functioning the liquid absorbing member 105a.
Explaining the removal of the liquid component from a different viewpoint, it can also be expressed as concentrating the ink constituting the image formed on the transfer body. Concentrating the ink means that the liquid component contained in the ink is reduced, so that the content ratio of the solid content such as the coloring material and the resin contained in the ink to the liquid component is increased.
Then, the second image after the liquid component is removed from the first image is moved to the transfer unit in contact with the recording medium conveyed by the recording medium transfer device 107 by the movement of the transfer body 101. While the second image after the liquid component is removed is in contact with the recording medium 108, the pressing member 106 presses the recording medium 108 to transfer the image (ink image) onto the recording medium. .. The post-transcriptional ink image transferred onto the recording medium 108 is an inverted image of the second image. In the following description, apart from the first image (ink image before liquid removal) and the second image (ink image after liquid removal) described above, the ink image after transfer may be referred to as a third image.
Since the reaction liquid is applied onto the transfer body and then the ink is applied to form an image, the reaction liquid remains in the non-image region (non-ink image formation region) without reacting with the ink. .. In this apparatus, the liquid absorbing member 105a is in contact (pressure contact) not only with the image but also with the unreacted reaction liquid, and the liquid component of the reaction liquid is also removed from the surface of the transfer body 101. Therefore, in the above, it is expressed and explained that the liquid component is removed from the image, but it does not mean that the liquid component is removed only from the image, and at least the liquid component should be removed from the image on the transfer body. It is used in the sense that it should be good. For example, it is also possible to remove the liquid component in the reaction solution imparted to the outer region of the first image together with the first image. The liquid component is not particularly limited as long as it does not have a constant shape, has fluidity, and has a substantially constant volume. For example, water, an organic solvent, etc. contained in an ink or a reaction liquid can be mentioned as liquid components.
Further, even when the above-mentioned clear ink is contained in the first image, the ink can be concentrated by the liquid absorption treatment. For example, when the clear ink is applied on the color ink containing the color material applied on the transfer body 101, the clear ink is present on the entire surface of the first image, or the first image is used. Clear ink is partially present in one or more places on the surface of the image, and color ink is present in the other parts. In the first image, where the clear ink is present on the color ink, the porous body absorbs the liquid component of the clear ink on the surface of the first image, and the liquid component of the clear ink moves. Along with this, the liquid component in the color ink moves toward the porous body side, so that the liquid component in the color ink is absorbed. On the other hand, in the place where the clear ink region and the color ink region exist on the surface of the first image, the liquid components of the color ink and the clear ink move to the porous body side, so that the liquid components are absorbed. Ink. The clear ink may contain a large amount of components for improving the transferability of the image from the transfer body 101 to the recording medium. For example, it is possible to increase the content of a component that becomes more adhesive to a recording medium by heating than a color ink.

Each configuration of the transfer type inkjet recording apparatus of this embodiment will be described below.

<Transcribant>
The transfer body 101 has a surface layer including an image forming surface. As a member of the surface layer, various materials such as resin and ceramic can be appropriately used, but a material having a high compressive elastic modulus is preferable in terms of durability and the like. Specific examples thereof include an acrylic resin, an acrylic silicone resin, a fluorine-containing resin, and a condensate obtained by condensing a hydrolyzable organosilicon compound. In order to improve the wettability, transferability, etc. of the reaction solution, it may be used after being surface-treated. Examples of the surface treatment include frame treatment, corona treatment, plasma treatment, polishing treatment, roughening treatment, active energy ray irradiation treatment, ozone treatment, surfactant treatment, silane coupling treatment and the like. A plurality of these may be combined. Further, any surface shape can be provided on the surface layer.
Further, the transfer material preferably has a compression layer having a function of absorbing pressure fluctuations. By providing the compression layer, the compression layer absorbs the deformation, disperses the fluctuation against local pressure fluctuations, and can maintain good transferability even during high-speed printing. Examples of the member of the compression layer include acrylonitrile-butadiene rubber, acrylic rubber, chloroprene rubber, urethane rubber, silicone rubber and the like. At the time of molding the rubber material, it is preferable that a predetermined amount of a vulcanizing agent, a vulcanization accelerator or the like is blended, and further, a foaming agent, hollow fine particles or a filler such as salt is blended as necessary to make the rubber material porous. As a result, since the bubble portion is compressed with a volume change in response to various pressure fluctuations, deformation in directions other than the compression direction is small, and more stable transferability and durability can be obtained. As the porous rubber material, there are a continuous pore structure in which each pore is continuous with each other and an independent pore structure in which each pore is independent. In the present invention, any structure may be used, and these structures may be used in combination.
Further, the transfer material preferably has an elastic layer between the surface layer and the compression layer. As the member of the elastic layer, various materials such as resin and ceramic can be appropriately used. Various elastomer materials and rubber materials are preferably used in terms of processing characteristics and the like. Specifically, for example, fluorosilicone rubber, phenylsilicone rubber, fluororubber, chloroprene rubber, urethane rubber, nitrile rubber, ethylene propylene rubber, natural rubber, styrene rubber, isoprene rubber, butadiene rubber, ethylene / propylene / butadiene copolymer, Examples thereof include nitrile butadiene rubber. In particular, silicone rubber, fluorosilicone rubber, and phenylsilicone rubber are preferable in terms of dimensional stability and durability because they have a small compression set. In addition, the change in elastic modulus with temperature is small, which is preferable in terms of transferability.
Various adhesives or double-sided tape may be used between the layers (surface layer, elastic layer, compression layer) constituting the transfer body to fix and hold them. Further, a reinforcing layer having a high compressive elastic modulus may be provided in order to suppress lateral elongation when mounted on the device and to maintain elasticity. Further, the woven fabric may be used as a reinforcing layer. The transfer material can be produced by arbitrarily combining each layer made of the above materials.
The size of the transfer body can be freely selected according to the target print image size. The shape of the transfer body is not particularly limited, and specific examples thereof include a sheet shape, a roller shape, a belt shape, and an endless web shape.

<Support member>
The transfer body 101 is supported on the support member 102. As a method of supporting the transfer body, various adhesives or double-sided tape may be used. Alternatively, the transfer body may be supported on the support member 102 by attaching the installation member made of metal, ceramic, resin, or the like to the transfer body.
The support member 102 is required to have a certain level of structural strength from the viewpoint of its transport accuracy and durability. As the material of the support member, metal, ceramic, resin or the like is preferably used. Above all, in addition to rigidity and dimensional accuracy that can withstand the pressure during transfer, aluminum, iron, stainless steel, acetal resin, epoxy resin, polyimide, in order to reduce inertia during operation and improve control responsiveness, Polyethylene, polyethylene terephthalate, nylon, polyurethane, silica ceramics, and alumina ceramics are preferably used. It is also preferable to use these in combination.

<Reaction solution applying device>
Each inkjet recording device of the present embodiment has a reaction solution applying device 103 that applies the reaction solution to the transfer body 101. The reaction solution application device 103 of FIG. 1 is a gravure having a reaction solution accommodating unit 103a for accommodating the reaction solution and reaction solution application members 103b and 103c for applying the reaction solution in the reaction solution accommodating unit 103a onto the transcript 101. The case of an offset roller is shown.

<Ink application device>
Each inkjet recording device of the present embodiment has an ink applying device 104 that applies ink to the transfer body 101 to which the reaction solution has been applied. The first image is formed by mixing the reaction liquid and the ink, and the liquid component is absorbed from the first image by the next liquid absorbing device 105.

<Liquid absorber>
In the present embodiment, the liquid absorbing device 105 has a liquid absorbing member 105a and a liquid absorbing pressing member 105b that presses the liquid absorbing member 105a against the first image on the transfer body 101.
The pressing member 105b operates to press the second surface of the liquid absorbing member 105a, so that the first surface is brought into contact with the outer peripheral surface of the transfer body 101, and the nip portion formed is passed through the first image. By doing so, the liquid absorption process from the first image can be performed. A region that enables the liquid absorbing member 105a to come into pressure contact with the outer peripheral surface of the transfer body 101 is used as the liquid absorbing treatment region.
The position of the pressing member 105 with respect to the transfer body 101 can be adjusted by a position control mechanism (not shown). For example, the pressing member 105 is configured to be reciprocally movable in the direction of arrow A shown in FIGS. The liquid absorbing member 105a can be brought into contact with the outer peripheral surface of the transfer body 101 at the timing, and can be separated from the outer peripheral surface.
The shapes of the liquid absorbing member 105a and the pressing member 105b are not particularly limited. For example, as shown in FIG. 1, the pressing member 105b has a cylindrical shape, the liquid absorbing member 105a has a belt shape, and the cylindrical pressing member 105b presses the belt-shaped liquid absorbing member 105a against the transfer body 101. It may be a configuration. Further, the pressing member 105b has a cylindrical shape, the liquid absorbing member 105a has a cylindrical shape formed on the peripheral surface of the cylindrical pressing member 105b, and the cylindrical pressing member 105b has a cylindrical liquid absorbing member 105a. May be pressed against the transfer body.
In the present invention, the liquid absorbing member 105a is preferably in the shape of a belt in consideration of the space in the inkjet recording apparatus and the like.
Further, the liquid absorbing device 105 having such a belt-shaped liquid absorbing member 105a may have a stretching member for stretching the liquid absorbing member 105a. In FIG. 1, 105c, 105d, 105e are tension rollers as tension members. These rollers and the belt-shaped liquid absorbing member 105a stretched on these rollers constitute a transport unit for transporting the porous body to be liquid-absorbed from the first image. With this transport unit, it is possible to carry in, carry out, and retransmit the porous body into the liquid absorption processing region.
In FIGS. 1 to 3, the pressing member 105b is also a roller member that rotates in the same manner as the tension roller, but the present invention is not limited to this.
In the liquid absorbing device 105, the liquid absorbing member 105a having a porous body is pressed against the first image by the pressing member 105b, so that the liquid component contained in the first image is absorbed by the liquid absorbing member 105a, and the first Remove the liquid component from the image. As a method of removing the liquid component in the first image, in addition to this method of pressing the liquid absorbing member, various other conventionally used methods such as a method of heating, a method of blowing low humidity air, and depressurization are performed. A combination of methods and the like may be used.

The temperature in the processing by the porous body of the liquid absorbing member to the first image by the liquid absorbing device can be set within a range in which the desired liquid absorbing effect can be obtained. When the wet liquid contains a surfactant for adjusting the contact angle, the temperature at the time of contact between the first surface of the porous body and the first image is less than the cloud point of the surfactant contained in the wet liquid. It is preferable to control the temperature to. By setting the temperature of the porous body to be less than the cloud point of the surfactant in the wetting liquid, the contact angle adjusting function of the target surfactant can be utilized more effectively.
The temperature at the time of contact between the first surface of the porous body and the first image when the temperature is lower than the cloud point of the surfactant in the wetting liquid is preferably selected from the range of 5 ° C. to 60 ° C.
For temperature control at the time of contact between the first surface of the porous body and the first image, a temperature control unit having a temperature control device including a heating device and a cooling device installed as needed is used in the inkjet recording device. This can be done by arranging them according to the configuration. For example, a temperature control device can be arranged inside the pressing member 105b shown in FIGS. 2 and 3 or in the vicinity of the outside thereof to control the temperature at the time of contact. The heating device and cooling device incorporated in the temperature control unit are not particularly limited, and known heating devices and cooling devices can be used.

Hereinafter, various conditions and configurations of the liquid absorbing device 105 will be described in detail.
(Preprocessing)
If necessary, the liquid absorbing device 105 may be provided with a wetting liquid applying device that constitutes a wetting liquid applying portion that applies the wetting liquid to the porous body of the liquid absorbing member before being carried into the liquid absorption processing region. it can.
When a water-repellent porous body is used, a wet liquid applying device that applies a wet liquid having a contact angle with the porous body of less than 90 ° before the porous body comes into contact with the first image. Can be pretreated by.
The wetting liquid is not particularly limited as long as the contact angle with the first surface of the porous body is less than 90 ° and the desired liquid absorbability can be obtained for the porous body. An aqueous liquid medium, for example, water or a mixture of water and a water-soluble organic solvent can be contained, and a surfactant can be added to appropriately adjust the surface tension thereof before use. The material used for preparing this wetting liquid is not particularly limited, but it is preferable to use a surfactant. As the surfactant, it is preferable to use at least one of a silicone-based surfactant and a fluorine-based surfactant.
Specific examples of the surfactants used are the fluorine-based surfactants F-444 (product name, manufactured by DIC), ZonylFS3100 (product name, manufactured by DuPont), CapstoneFS-3100 (product name, The Chemours Company LLC). And BYK349 (product name, manufactured by BYK), which is a silicone-based surfactant. The water is preferably water that has been deionized by ion exchange or the like. The type of water-soluble organic solvent is not particularly limited, and any known organic solvent such as ethanol or isopropyl alcohol can be used.
The method of applying the wetting liquid to the porous body is not particularly limited to immersion, coating, under droplets, etc., but for stable application of the wetting liquid and high-speed application in the apparatus, a roller pressurization method is applied. The method is preferred.
FIG. 2 shows a wetting liquid applying device 10 by combining a chamber (wetting liquid accommodating portion) containing the wetting liquid as the wetting liquid applying members 10a and 10b and an offset roller (member for applying the wetting liquid). ..
Further, in the present invention, the timing of applying the wetting liquid is not particularly limited. When the drum-shaped or endless web-shaped liquid absorbing member is sequentially transported around and pretreated, the wetting liquid may be applied every one lap, or the wetting liquid may be applied once every few laps. The timing of applying the wetting liquid may be controlled. The wetting liquid applying member may be configured to move up and down using a motor, a cam mechanism, or an air cylinder so that it can be brought into contact with and separated from the liquid absorbing member.
In the embodiment shown in FIGS. 2 and 3, before the liquid absorbing member 105a is brought into contact with the first image, pretreatment is performed by the wetting liquid applying devices 10 and 11 that apply the wetting liquid to the porous body of the liquid absorbing member. Wetting liquid as can be applied.
Wetting so that the movement to the position where the wetting liquid is applied to the liquid absorbing member 105a and the operation of separating from the liquid absorbing member 105a, for example, the reciprocating movement in the arrow C direction shown in the drawing are possible at the required timing. A liquid application device can be installed. For example, the above-mentioned reciprocating movement can be performed by arranging the wetting liquid applying device on an elevating stage (not shown) that can be elevated by an elevating air cylinder (not shown).
The applying pressure of the wetting liquid is not particularly limited, but if it is 0.981 N / cm ² (0.1 kgf / cm ² ) or more, the wet liquid is stably applied and applied at high speed in the apparatus. It is preferable because it can be used. Further, when the pressure is 98.07 N / cm ² (10 kgf / cm ² ) or less, the structural load on the apparatus can be suppressed, which is preferable.

(Recovery liquid)
In the present invention, a recovery liquid that imparts a recovery liquid having a viscosity lower than that of the ink and the reaction liquid to the liquid absorption member 105a while repeatedly contacting the porous body of the liquid absorption member 105a with the first image. The granting device 110 is provided.
According to the study of the present inventor, while the porous body is repeatedly used for the liquid absorption treatment, the absorbed liquid is dried and thickened inside the liquid absorption member 105a, so that the inside of the liquid absorption member 105a is thickened. It has been found that the flow resistance at the site becomes high and image flow may occur.
The present invention solves the above-mentioned problems by applying a recovery liquid to the liquid absorbing member 105a during repeated use to suppress thickening of the liquid component inside the porous body and suppress image flow.
As a method for applying the recovery liquid applied to the present invention, various conventionally known methods can be appropriately used. Examples include those using an inkjet method, die coating, blade coating, gravure rollers, and those in which offset rollers are combined.
In FIGS. 1 and 2, the recovery liquid application members 110a and 110b form a recovery liquid application unit by combining a chamber (recovery liquid storage unit) containing the recovery liquid and an offset roller (member for applying the recovery liquid). The liquid application device 110 is shown.
The recovery liquid can be prepared with water as the main component, and preferably further contains a water-soluble organic solvent. The water is preferably water that has been deionized by ion exchange or the like. The type of water-soluble organic solvent is not particularly limited, and any known organic solvent such as ethanol or isopropyl alcohol can be used. It may also contain a surfactant. Specific examples of the surfactant include acetylenolol E100 (manufactured by Kawaken Fine Chemical Co., Ltd.).
The recovery liquid can also be prepared by a method of adjusting the viscosity of the ink to a predetermined value by using a component obtained by removing the coloring material from the ink component. In this case, various materials described above in the sections of "(water and water-soluble organic solvent)" and "(other additives)" regarding ink can be used.
The recovery liquid has a low viscosity with respect to the ink and the reaction liquid. Since the viscosity is low, the viscosity of the liquid after the recovery liquid is applied tends to be low, and the flow resistance at the time of liquid absorption is lowered, so that the occurrence of image flow can be efficiently suppressed. Here, the viscosities of the ink, the reaction solution, and the recovery solution are the viscosities before drying. The viscosity of the recovery liquid is preferably 0.3 mPa · s or more lower than that of the ink and the reaction liquid, and more preferably 0.6 mPa · s or more.
Further, the recovery liquid preferably has a higher water concentration than the ink and the reaction liquid. Due to the high water concentration, the replacement rate between the residual solvent inside the absorber and the applied recovery liquid when the recovery liquid is applied increases. Therefore, the viscosity is lowered and the flow resistance at the time of liquid absorption is lowered, so that the occurrence of image flow can be efficiently suppressed.
Further, it is also preferable that the recovery liquid has a lower vapor pressure than the reaction liquid and the ink. Since the recovery liquid applied to the inside of the absorber is hard to evaporate, it is hard to thicken and the amount of the recovery liquid used can be suppressed. Examples of the organic solvent for lowering the vapor pressure include ethylene glycol monoethyl ether and ethylene glycol monomethyl ether.

The recovery liquid may be applied every time, but it is also preferable to apply the recovery liquid intermittently as long as the removal is not insufficient. By intermittently applying the recovery liquid, it is possible to suppress the amount of the recovery liquid used. When intermittently applied, it is preferable to separate the recovery liquid applying device 110 by a device (not shown) that separates the recovery liquid applying device 110 from the liquid absorbing member 105a. For example, the operation of moving to the position where the recovery liquid is applied to the liquid absorbing member 105a and the operation of separating from the liquid absorbing member 105a, for example, the reciprocating movement in the direction of the arrow B shown in the figure can be performed at the required timing. A recovery liquid applying device can be installed in. This reciprocating operation can be performed by arranging a recovery liquid application device on an elevating stage (not shown) that can be elevated by an elevating air cylinder (not shown).
Further, the timing of applying the recovery liquid to the liquid absorbing member 105a for more efficient recovery processing is controlled by the recovery liquid application control unit that controls whether or not the recovery liquid is applied to the porous body in the recovery liquid application device. This can be performed by the recovery liquid application control step instructed by.
As the information for controlling the presence or absence of the recovery liquid to be applied, it is preferable to use at least one of the following information and set the amount of the recovery liquid to be applied to the minimum necessary amount.
(A) The timing of applying the recovery liquid, which is obtained in the test run and enables effective recovery processing, for example, the elapsed time from the time when the recovery liquid was applied last time to the time when the recovery liquid is applied next time.
(B) Predicted value of viscosity and / or amount of liquid in the porous body.
(C) Environmental information including temperature and / or humidity obtained by the environmental information acquisition device.
(D) Elapsed time Elapsed time until the liquid absorption step after the recovery liquid applying step obtained by the acquisition device is completed.
By using the information (A), it is possible to control the application of the recovery liquid at regular intervals.
Information (B) can be obtained from information such as the applied ink, the reaction solution, the initial viscosity and the applied amount of the recovery solution, and the elapsed time.
By using the information (C) acquired by using a known detection device that can detect temperature and / or humidity and retrieve the information, it is possible to predict the increase in viscosity of the liquid inside the porous body inside the device. It is more preferable to carry out while grasping the temperature and / or humidity of. By grasping the temperature and humidity in this way, it is possible to predict the increase in viscosity more accurately, and it is possible to obtain the minimum necessary amount of the recovery liquid.
Further, when the recovery liquid is not applied for a certain period of time or more, image flow may easily occur if the liquid absorption treatment is performed without applying the recovery liquid. For the porous body in such a state, by using the information (D), the liquid absorption processing region is passed through the liquid absorption processing region as it is without being pressed by the pressing member 105a, that is, in an unused state, and the recovery liquid is once applied. It is preferable to reuse it after that. The passage of the liquid absorption processing region of the liquid absorption member in the unused state can be performed, for example, by passing and transporting the liquid absorption member by the transfer device.
The idle operation in such a liquid absorption processing region can be instructed by a control unit that controls the position of the pressing member 105a and the transfer timing of the liquid absorption member 105a.
It is also preferable to use the same liquid as the recovery liquid used for the pretreatment of the liquid absorbing member 105a because the apparatus is simplified.
Further, the liquid absorbing device 105 can remove the reaction liquid which is a liquid component not only from the image but also from the non-image part. In addition, the recovery liquid used in the recovery liquid application portion used in the present invention also has an effect of promoting the removal of the reaction liquid remaining in the non-imaging portion on the transcript. The viscosity of the reaction solution on the transcript increases due to the drying of the solvent used in the reaction solution from the reaction solution application step, and a large amount of the reaction solution remains on the transcript depending on the reaction solution. Although the detailed principle is unknown, the liquid component contained in the liquid absorbing member may be squeezed out from the porous body near the inlet of the pressing process of the liquid absorbing member and applied to the reaction liquid on the transfer body. Since the recovery liquid has a lower viscosity than the reaction liquid, the liquid content in the porous body to which the recovery liquid is applied has a low viscosity, and the low-viscosity liquid content in the porous body seeps out onto the transcript. Is granted. As a result, while reducing the viscosity of the reaction solution on the transfer body, the liquid absorption flow resistance at the time of pressing the porous body of the liquid absorption member is reduced, so that the removal of the reaction solution in the non-image area is also promoted. It is presumed to be.
Further, it is also preferable that the recovery liquid application device also serves as the wet liquid application device described above, as in the inkjet recording device 3 shown in FIG. At that time, it is necessary to use a liquid that satisfies the requirements of the recovery liquid and the wetting liquid at the same time, the viscosity is low with respect to the ink and the reaction liquid, and the contact angle with the liquid absorbing member is less than 90 °. With this configuration, the device can be simplified and the cost can be reduced.

(Pressurization condition)
When the pressure of the porous body pressing against the image on the transfer body is 2.94 N / cm ² (0.3 kgf / cm ² ) or more, the liquid component in the first image is solidified in a shorter time. It is preferable because it can be separated and the liquid component can be removed from the first image. Further, when the pressure is 98.07 N / cm ² (10 kgf / cm ² ) or less, the structural load on the apparatus can be suppressed, which is preferable. The contact pressure with respect to the first image of the porous body in the present invention indicates the nip pressure between the transfer body 101 and the liquid absorbing member 105a, and is a surface pressure distribution measuring instrument (product name: I-SCAN). , Nitta Co., Ltd.), the surface pressure was measured, and the weight in the pressurized region was divided by the area to calculate the value.

(Time of action)
The action time for bringing the liquid absorbing member 105a into contact with the first image is preferably within 50 ms (milliseconds) in order to further suppress the coloring material in the first image from adhering to the liquid absorbing member. .. The action time in the present specification is calculated by dividing the pressure sensing width in the moving direction of the recorded body by the moving speed of the recorded body in the above-mentioned surface pressure measurement. Hereinafter, this action time will be referred to as a liquid absorption nip time.
In this way, the liquid component is absorbed from the first image on the transfer body 101, and a second image in which the liquid content is reduced is formed. The second image is then transferred onto the recording medium 108 at the transfer section. The apparatus configuration and conditions at the time of transfer will be described.

<Pressing member for transfer>
In the present embodiment, the recording medium 108 is pressed by the transfer pressing member 106 while the second image and the recording medium 108 conveyed by the recording medium transfer device 107 are in contact with each other. The image (ink image) is transferred onto the image. By removing the liquid component contained in the first image on the transfer body 101 and then transferring the liquid component to the recording medium 108, it is possible to obtain a recorded image in which curling, cockling, and the like are suppressed.
The pressing member 106 is required to have a certain level of structural strength from the viewpoint of transport accuracy and durability of the recording medium 108. As the material of the pressing member 106, metal, ceramic, resin or the like is preferably used. Above all, in addition to rigidity and dimensional accuracy that can withstand the pressure during transfer, aluminum, iron, stainless steel, acetal resin, epoxy resin, polyimide, in order to reduce inertia during operation and improve control responsiveness, Polyethylene, polyethylene terephthalate, nylon, polyurethane, silica ceramics, and alumina ceramics are preferably used. Moreover, you may use these in combination.
The time during which the pressing member 106 is pressed to transfer the second image on the transfer body 101 to the recording medium 108 is not particularly limited, but the transfer is performed well and the durability of the transfer body is not impaired. It is preferably 5 ms or more and 100 ms or less. The pressing time in the present embodiment indicates the time during which the recording medium 108 and the transfer body 101 are in contact with each other, and is a surface pressure distribution measuring instrument (product name: I-SCAN, manufactured by Nitta Co., Ltd.). The surface pressure was measured by dividing the length of the pressurized region in the transport direction by the transport speed to calculate the value.
Further, the pressure pressed by the pressing member 106 to transfer the second image on the transfer body 101 to the recording medium 108 is not particularly limited, but the transfer is performed well and the durability of the transfer body is impaired. Try not to. Therefore, the pressure ^{is preferably 9.8 N / cm 2} (1 kgf / cm ² ) or more and 294.2 N / cm ² (30 kgf / cm ² ) or less. The pressure in the present embodiment indicates the nip pressure between the recording medium 108 and the transfer body 101, the surface pressure is measured by a surface pressure distribution measuring device, and the weight in the pressure region is divided by the area to obtain a value. Is calculated.
The temperature when the pressing member 106 is pressed to transfer the second image on the transfer body 101 to the recording medium 108 is also not particularly limited, but when the ink contains a resin component, it is contained in the ink. It is preferable that the resin component is at least the glass transition point or at least the softening point. Further, for heating, it is preferable to include a heating device for heating the second image on the transfer body 101, the transfer body 101, and the recording medium 108.
The shape of the pressing member 106 is not particularly limited, and examples thereof include a roller shape.

<Recording medium and recording medium transfer device>
In the present embodiment, the recording medium 108 is not particularly limited, and any known recording medium can be used. Examples of the recording medium include long ones wound in a roll shape and single-striped ones cut to a predetermined size. Examples of the material include paper, plastic film, wooden board, corrugated cardboard, metal film and the like.
Further, the recording medium transporting device 107 for transporting the recording medium 108 is composed of the recording medium feeding roller 107a and the recording medium winding roller 107b, but it is sufficient if the recording medium can be conveyed, and is particularly limited to this configuration. It's not a thing.

<Control system>
The transfer type inkjet recording device in the present embodiment has a control system that controls each device. FIG. 5 is a block diagram showing a control system of the entire device in the transfer type inkjet recording devices 1 to 3 shown in FIGS. 1 to 3.
In FIG. 5, 301 is a recording data generation unit such as an external print server, 302 is an operation control unit such as an operation panel, 303 is a printer control unit for executing a recording process, and 304 is a recording medium for transporting a recording medium. The transfer control unit, 305, is an inkjet device for printing.
FIG. 6 is a block diagram of a printer control unit in the transfer type inkjet recording apparatus of FIG.
401 is a CPU that controls the entire printer, 402 is a ROM for storing a control program of the CPU, and 403 is a RAM for executing the program. Reference numeral 404 is an application specific integrated circuit (ASIC) incorporating a network controller, a serial IF controller, a head data generation controller, a motor controller, and the like. Reference numeral 405 is a liquid absorbing member transport control unit for driving the liquid absorbing member transport motor 406, which is command controlled from the ASIC 404 via the serial IF. Reference numeral 407 is a transfer body drive control unit for driving the transfer body drive motor 408, and the command is similarly controlled from the ASIC 404 via the serial IF. Reference numeral 409 is a head control unit, which generates final ejection data of the inkjet device 305, generates a drive voltage, and the like. Reference numeral 410 denotes a control unit of the liquid application unit, which can be used as an elevation control unit of the recovery liquid application device for driving the elevating air cylinder (not shown) of the recovery liquid application device, that is, a recovery liquid application control unit. .. The control unit 410 is command-controlled from the ASIC 404 via the serial IF.
The recovery liquid application device and the wetting liquid application device shown in FIGS. 2 and 3 can also be controlled by the control unit 410.

(Direct drawing type inkjet recording device)
Another embodiment of the present invention is a direct drawing type inkjet recording apparatus. In a direct drawing inkjet recording device, the recording object is a recording medium on which an image should be formed.
FIG. 4 is a schematic view showing an example of a schematic configuration of the direct drawing type inkjet recording apparatus 200 according to the present embodiment. The direct drawing type inkjet recording device does not have the transfer body 101, the support member 102, and the transfer body cleaning member 109 as compared with the transfer type inkjet recording device described above, except that an image is formed on the recording medium 208. , Has the same means as the transfer type inkjet recording device.
Therefore, the reaction liquid accommodating portion 203a for applying the reaction liquid to the recording medium 208, the reaction liquid applying device 203 having the reaction liquid applying members 203b and 203c, and the ink applying device 204 for applying ink to the recording medium 208 are transfer type inkjets. It has the same configuration as the recording device, and the description thereof will be omitted. Similarly, the description of the liquid absorbing device 205 that absorbs the liquid component contained in the first image by the liquid absorbing member 205a that comes into contact with the first image on the recording medium 208 will be omitted.
In the direct drawing type inkjet recording device of the present embodiment, the liquid absorbing device 205 is a pressing member for liquid absorption that presses the liquid absorbing member 205a and the liquid absorbing member 205a against the first image on the recording medium 208. It has 205b. 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 device can be used. Further, the liquid absorbing device 205 may have a tensioning member for tensioning the liquid absorbing member. In FIG. 4, 205c, 205d, 205e, 205f, 205g are tension rollers as tension members. The number of tension rollers is not limited to the five in FIG. 4, and the required number may be arranged according to the device design. Further, the ink applying unit 204 applies ink to the recording medium 208, and the liquid absorbing member 205a is brought into contact with the first image on the recording medium to face the liquid component removing unit that removes the liquid component. A recording medium support member (not shown) that supports the recording medium from below may be provided at the position.

Further, in the illustrated device, while the liquid absorbing member 205a is repeatedly in contact with the image, the recovery liquid having a viscosity lower than that of the ink and the reaction liquid is applied to the liquid absorbing member 205a to the porous body of the liquid absorbing member 205a. It has a liquid applying device 210. As a method of applying the recovery liquid, various conventionally known methods can be appropriately used. Examples include those using an inkjet method, die coating, blade coating, gravure rollers, and those in which offset rollers are combined.
FIG. 4 shows a recovery liquid application device 210 by combining a chamber and an offset roller as recovery liquid application members 210a and 210b.
Further, although not shown, it is also preferable to separately have the wetting liquid applying device described above, as shown in the transfer type inkjet recording device 2 of FIG. Further, as shown in the transfer type inkjet recording device 4 of FIG. 3, it is also preferable that the wetting liquid applying device also serves as a recovery liquid applying device.

<Recording medium transfer device>
In the direct drawing type inkjet recording device of the present embodiment, the recording medium transfer device 207 is not particularly limited, and a transfer device in a known direct drawing type inkjet recording device can be used. As an example, as shown in FIG. 2, a recording medium transport device having a recording medium feeding roller 207a, a recording medium winding roller 207b, and a recording medium transport roller 207c, 207d, 207e, 207f can be mentioned.

<Control system>
The direct drawing type inkjet recording device in the present embodiment has a control system for controlling each device. The block diagram showing the control system of the entire device in the direct drawing type inkjet recording device shown in FIG. 4 is as shown in FIG. 5, similar to the transfer type inkjet recording device shown in FIG.
FIG. 7 is a block diagram of a printer control unit in the direct drawing type inkjet recording apparatus of FIG. It is the same as the block diagram of the printer control unit in the transfer type inkjet recording apparatus shown in FIG. 6 except that the transfer body drive control unit 407 and the transfer body drive motor 408 are not provided.
That is, 501 is a CPU that controls the entire printer, 502 is a ROM for storing a control program of the CPU, and 503 is a RAM for executing the program. Reference numeral 504 is an ASIC having a built-in network controller, serial IF controller, head data generation controller, motor controller, and the like. Reference numeral 505 is a liquid absorbing member transport control unit for driving the liquid absorbing member transport motor 506, which is command controlled from the ASIC 504 via the serial IF. Reference numeral 509th is a head control unit, which generates final ejection data of the inkjet device 305, generates a drive voltage, and the like. Further, reference numeral 510 denotes a control unit that controls the amount of application in the liquid application unit. The control unit 510 is command-controlled from the ASIC 404 via the serial IF. The control unit 510 can control the recovery liquid application device shown in FIG. 4 and the wet liquid application device additionally provided as needed in the same manner as the transfer type inkjet recording devices 1 to 3. Therefore, the control unit 510 can be used as a recovery liquid application control unit or a wetting liquid application control unit.
Further, as the information used for controlling the timing of applying the recovery liquid to the liquid absorbing member, the following information can be used in addition to the above-mentioned information (A) to (D).
(E) Information on the type of paper (recording medium) obtained by the paper information acquisition device (recording medium information acquisition device).
Information on the type of paper can be obtained by comparing data such as surface roughness and basis weight (weight) with library data held in advance, or by information input from the user interface.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited to the following examples as long as the gist of the present invention is not exceeded. In the description of the following examples, the term "part" is based on mass unless otherwise specified.

(Example 1)
In this embodiment, the transfer type inkjet recording apparatus 1 shown in FIG. 1 was used.
The transfer body 101 in this embodiment is fixed to the support member 102 with an adhesive.
In this example, a PET sheet having a thickness of 0.5 mm coated with silicone rubber (product name: KE12, manufactured by Shin-Etsu Chemical Co., Ltd.) to a thickness of 0.3 mm was used as the elastic layer of the transfer body. Further, glycidoxypropyltriethoxysilane and methyltriethoxysilane are mixed at a molar ratio of 1: 1 to prepare a mixture of a condensate obtained by heating and refluxing and a photocationic polymerization initiator (product name: SP150, manufactured by ADEKA). did. Atmospheric pressure plasma treatment is performed so that the contact angle of water on the surface of the elastic layer is 10 degrees or less, the above mixture is applied onto the elastic layer, and UV irradiation (high pressure mercury lamp, integrated exposure amount 5000 mJ / cm ² ) is performed. A transfer film 101 having a 0.5 μm-thick surface layer formed on an elastic body was produced by forming a film by thermosetting (150 ° C. for 2 hours).
In this configuration, although not shown for the sake of brevity, a double-sided tape was used to hold the transfer body 101 between the transfer body 101 and the support member 102.
Further, in this configuration, the surface of the transfer body 101 is set to 60 ° C. by a heating device (not shown).
The reaction solution given by the reaction solution applying device 103 had the following composition, and the applied amount was 1 g / m ² .
・ Citric acid: 30.0 parts ・ Potassium hydroxide: 3.5 parts ・ Glycerin: 5.0 parts ・ Surfactant (Product name: Megafuck F444, manufactured by DIC Corporation): 1.0 part ・ Ion-exchanged water : Remaining The viscosity of the above reaction solution was 3.5 mPa · s.
The ink was prepared as follows.

<Preparation of pigment dispersion>
Carbon black (product name: Monac 1100, manufactured by Cabot), 10 parts of resin aqueous solution (styrene-ethyl acrylate-acrylic acid copolymer, acid value 150, weight average molecular weight (Mw) 8,000, resin content 20 15 parts of 0.0% by mass aqueous solution neutralized with potassium hydroxide aqueous solution) and 75 parts of pure water were mixed and charged into a batch type vertical sand mill (manufactured by IMEX), and 200 parts of 0.3 mm diameter zirconia beads were added. The dispersion treatment was carried out for 5 hours while being filled and cooled with water. After centrifuging this dispersion to remove coarse particles, a black pigment dispersion having a pigment content of 10.0% by mass was obtained.

<Preparation of resin particle dispersion>
20 parts of ethyl methacrylate, 3 parts of 2,2'-azobis- (2-methylbutyronitrile) and 2 parts of n-hexadecane were mixed and stirred for 0.5 hours. This mixture was added dropwise to 75 parts of an 8% aqueous solution of a styrene-butyl acrylate-acrylic acid copolymer (acid value: 130 mgKOH / g, weight average molecular weight (Mw): 7,000), and the mixture was stirred for 0.5 hours. did. Next, ultrasonic waves were irradiated with an ultrasonic irradiator for 3 hours. Subsequently, a polymerization reaction was carried out at 80 ° C. for 4 hours in a nitrogen atmosphere, and the mixture was cooled to room temperature and then filtered to prepare a resin particle dispersion having a resin content of 25.0% by mass.

<Ink preparation>
The resin particle dispersion and the pigment dispersion obtained above were mixed with the following components. The balance of the ion-exchanged water is an amount in which the total of all the components constituting the ink is 100.0% by mass.
-Pigment dispersion (content of coloring material is 10.0% by mass): 40.0% by mass
-Resin particle dispersion: 20.0% by mass
-Glycerin: 7.0% by mass
-Polyethylene glycol (number average molecular weight (Mn): 1,000): 3.0% by mass
-Surfactant: Acetylenol E100 (manufactured by Kawaken Fine Chemical Co., Ltd.): 0.5% by mass
-Ion-exchanged water: The balance was sufficiently stirred and dispersed, and then pressure-filtered with a microfilter (manufactured by FUJIFILM Corporation) having a pore size of 3.0 μm to prepare black ink.
The viscosity of the ink was 2.1 mPa · s.
The ink application device 104 uses an inkjet head of a type that uses an electric-heat conversion element and ejects ink by an on-demand method, and the amount of ink applied is 20 g / m ² .
The liquid absorbing member 105a is adjusted to have a speed equivalent to the moving speed of the transfer body 101 by the transport rollers 105c, 105d, 105e that convey the liquid absorbing member while stretching it. Further, the recording medium 108 is conveyed by the recording medium feeding roller 107a and the recording medium winding roller 107b so as to have a speed equivalent to the moving speed of the transfer body 101. In this example, the transport speed was 0.2 m / s, and Aurora-coated paper (manufactured by Nippon Paper Industries, Ltd., basis weight 104 g / m ² ) was used as the recording medium 108.
Further, the nip pressure between the transfer body 101 and the liquid absorbing member 105a is applied to the liquid absorbing member 105b so ^{that the average pressure is 39.23 N / cm 2} (4 kg / cm ^2). Further, as the pressing member 105b in the liquid absorbing device, a member having a roller diameter of φ200 mm was used.
As the liquid absorbing member 105a, a support material made of a porous hydrophilic PTFE having an average pore diameter of 0.2 μm and a non-woven fabric was used. The galley of the liquid absorbing member I was 8 seconds.
In this embodiment, the recovery liquid is applied to the liquid absorbing member 105a by the recovery liquid application device 110 having an offset roller. In Example 1, a recovery solution A having the following composition was used as the recovery solution.
-Glycerin: 21.0% by mass
-Polyethylene glycol (number average molecular weight (Mn): 1,000): 1.0% by mass
-Surfactant: Acetylenol E100 (manufactured by Kawaken Fine Chemical Co., Ltd.): 0.5% by mass
-Ion-exchanged water: The remaining recovery liquid A had almost the same water concentration and vapor pressure as the ink, but the viscosity was 1.6 mPa · s, which was lower than that of the ink. Further, the reaction liquid application, ink application, and liquid absorption treatment steps were repeated 1000 times in a cycle of once every 10 seconds, and the recovery liquid was applied to each of the above cycles.
The temperature inside the inkjet device was 40 ° C. and the humidity was 40%.

(Example 2)
Only the composition of the recovery solution was changed with respect to Example 1.
As the recovery liquid, a recovery liquid B having the following composition, which has a high water concentration with respect to the ink and the reaction liquid, was used.
-Ion-exchanged water: 100 parts The viscosity of the recovery liquid B was 1 mPa · s.

(Example 3)
Only the composition of the recovery solution was changed with respect to Example 1.
As the recovery liquid, a recovery liquid C having the following composition, which has a lower vapor pressure than the ink and the reaction liquid, was used.
・ Non-aqueous solvent: Ethylene glycol monoethyl ether: 80.0 parts ・ Surfactant: Acetyleneol E100 (product name): 0.5 parts ・ Ion-exchanged water: 19.5 parts The viscosity of the recovery liquid is 1.7 mPa ・ s. Met.

(Example 4)
Only the timing of applying the recovery liquid was changed with respect to Example 1.
It was applied once every three times with respect to the cycle of the reaction solution application, the ink application, and the liquid absorption treatment step.

(Example 5)
The cycle between the reaction liquid application, ink application, and liquid absorption treatment steps was changed with respect to Example 1. The reaction liquid application, ink application, and liquid absorption treatment steps were repeated 1000 times in a cycle of once every 10 seconds as in Example 1, but once in 100 times for 20 minutes, the recovery liquid application device and the liquid absorption treatment step. For both image formation, the device was shut down.
In addition, the recovery solution was applied every time for the above cycle.

(Example 6)
The application sequence of the recovery solution was changed with respect to Example 5.
In addition to the conditions of the recovery liquid application step in Example 5, the liquid absorbing member 105a is passed through the pressing portion 105a in a state of being separated from the transfer body 101 at a rate of once in 10 times of the recovery liquid application step. A maintenance operation was performed to apply the recovery liquid.

(Example 7)
The conditions were such that the temperature and humidity inside the inkjet device were different from those of Example 1.
The temperature inside the inkjet device was 60 ° C. and the humidity was 30%.
Further, the recovery liquid was applied once every three times with respect to the cycle of the reaction liquid application, the ink application, and the liquid absorption treatment step.

(Example 8)
With respect to Example 7, whether or not the recovery liquid was applied was controlled from the information by detecting the temperature and humidity in the apparatus.
By control, the recovery liquid was applied every time for each cycle of reaction liquid application, ink application, and liquid absorption treatment.

(Example 9)
For Example 1, OK Prince woodfree paper (product name, manufactured by Oji Paper Co., Ltd., 127.9 g / m ² ) was used using the direct drawing type inkjet recording apparatus shown in FIG.
The recovery liquid was applied once every three times with respect to the cycle of reaction liquid application, ink application, and liquid absorption treatment.

(Example 10)
With respect to Example 9, the presence or absence of the recovery liquid was detected by detecting the type of the recording medium and controlled from the information.
By control, the recovery liquid was applied every time for each cycle of reaction liquid application, ink application, and liquid absorption treatment.

(Example 11)
For Example 1, a transfer type inkjet recording device 2 having a wetting liquid applying device to a liquid absorbing member was used. Further, as the liquid absorbing member 105a, a material obtained by laminating a support material made of a porous PTFE having an average pore diameter of 0.2 μm and a non-woven fabric was used. The galley of this absorbing member was 8 seconds.
Further, as a wetting liquid, 10 g / m ² having the following composition was applied. After the wetting liquid was applied, it was used in the same manner as in Example 1, and other conditions were the same as in Example 1. The contact angle of the wet liquid with the liquid absorbing member was 85 °.
・ Glycerin: 10.0% by mass
-Surfactant (Product name: Megafuck F444, manufactured by DIC Corporation): 2.0% by mass
・ Ion-exchanged water: Residual mass%
The viscosity of the above composition was 1.4 mPa · s.

(Example 12)
A transfer type inkjet recording device 3 having a wetting liquid / recovery liquid applying device was used with respect to Example 11.
As the wetting liquid / recovery liquid D, the one having the following composition was used. The cycle of granting was the same as in Example 1. This wettable powder / recovery liquid has a high water concentration and a low viscosity with respect to the ink and the reaction liquid. The contact angle of the wet liquid / recovery liquid with the liquid absorbing member was 85 °.
・ Glycerin: 10.0% by mass
-Surfactant (Product name: Megafuck F444, manufactured by DIC Corporation): 2.0% by mass
・ Ion-exchanged water: Residual mass%
The viscosity of the recovery liquid D was 1.4 mPa · s.

(Comparative Example 1)
Liquid absorption was repeated with respect to Example 1 without applying the recovery liquid.

(Comparative Example 2)
Only the composition of the recovery solution was changed with respect to Example 1.
As the recovery liquid, a recovery liquid E having the following composition, which has a high viscosity with respect to the ink and the reaction liquid, was used.
-Glycerin: 50.0% by mass
-Polyethylene glycol (number average molecular weight (Mn): 1,000): 1.0% by mass
-Surfactant: Acetylenol E100 (manufactured by Kawaken Fine Chemical Co., Ltd.): 0.5% by mass
-Ion-exchanged water: The viscosity of the remaining recovery liquid E was 6.5 mPa · s.

[Evaluation]
The presence or absence of image flow and the amount of recovery liquid used were evaluated in each Example and Comparative Example. The evaluation results are shown in Table 1-1 and Table 1-2. In the present invention, AA to B of the evaluation criteria of each of the following evaluation items are set to a preferable level, and C is set to an unacceptable level.

<Image flow>
The amount of movement of the coloring material at the edge of the image after the liquid is absorbed is shown, and the smaller the amount of movement, the higher the image quality, which is preferable. The evaluation criteria are as follows.
AA: Almost no image flow was observed even after repeated use 10,000 times under the above-mentioned conditions.
A: A slight image flow was observed when the image was used repeatedly 10,000 times under the above-mentioned conditions, but the level was not noticeable.
B: A slight image flow was observed when the image was used repeatedly 5000 times under the above-mentioned conditions, but the level was not noticeable.
C: The image flow was large.

<Amount of recovery liquid used>
The amount of recovery liquid used is shown, and the evaluation criteria are as follows.
A: It was the minimum amount of recovery liquid used.
B: The amount of recovery liquid used was such that no cost problem occurred.

As described above, in the present invention, when the porous body having the liquid absorbing member is repeatedly used for the liquid absorbing treatment from the image formed by using the reaction liquid for thickening the ink for promoting the fixing of the coloring material, it is re-used. A recovery liquid having a viscosity lower than that of the ink and the reaction liquid is applied to the porous body before use. According to the present invention, by applying the recovery liquid to the porous body before reuse, thickening of the liquid inside the porous body due to repeated use of the porous body is suppressed, and the occurrence of image flow is prevented. High-quality image formation is possible.

1 Transfer type inkjet recording device 10 Wetting liquid applying device 10a, b Wetting liquid applying member 11 Wetting liquid / recovery liquid applying device 11a, b Wetting liquid / recovery liquid applying member 101 Transfer body 102 Support member 102a Rotation axis 103 reaction of support member Liquid application device 103a Reaction liquid storage unit 103b, c Reaction liquid application member 104 Ink application device 105 Liquid absorption device 105a Liquid absorption member 105b Pressing member for liquid absorption 105c, d, e Stretching roller 106 Pressing member for transfer 107 Recording Media transport device 107a Recording medium feeding roller 107b Recording medium winding roller 108 Recording medium 109 Transfer cleaning member 110 Recovery liquid application device 110a, b Recovery liquid application member

Claims (41)

To the recording medium, an ink containing a water-soluble liquid medium and the coloring material, and applying a reaction liquid for thickening the ink reacts with the ink, first image containing an aqueous liquid component and the colorant And the image forming unit that forms
From the first image, a liquid absorbing member having a porous body that absorbs at least a part of the aqueous liquid component,
It is an inkjet recording device equipped with
A transport unit that repeatedly carries in and out of the liquid absorption member into and out of the liquid absorption treatment region where the liquid absorption treatment from the first image is performed by the liquid absorption member.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
A recovery liquid application control unit that intermittently applies the recovery liquid to the liquid absorption member by the recovery liquid application unit, and a recovery liquid application control unit.
An inkjet recording device characterized by the above. A wet liquid applying portion that applies a wet liquid having a contact angle of less than 90 ° to the first surface of the porous body to the first surface of the porous body before being carried into the liquid absorption treatment region. The inkjet recording apparatus according to claim 1, further comprising. The inkjet recording apparatus according to claim 2, wherein the recovery liquid applying portion also serves as the wetting liquid applying portion. The inkjet recording apparatus according to any one of claims 1 to 3, wherein the recovery liquid has a higher concentration of water than the reaction liquid and ink. Before Symbol recovery liquid, an ink jet recording apparatus according to any one of claims 1 to 4, wherein said that the reaction liquid and a low vapor pressure than ink. Any one of claims 1 to 5, further comprising a transport control unit for passing the liquid absorption member carried into the liquid absorption treatment region and transporting the liquid absorption member to the recovery liquid application unit. The inkjet recording apparatus according to the section. The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. The inkjet recording apparatus according to any one of claims 1 to 6 , wherein the second image is transferred to a recording medium for forming a final image. The inkjet recording apparatus according to claim 7 , further comprising a recovery liquid application control unit that controls the presence or absence of the recovery liquid application by the recovery liquid application unit to the liquid absorption member. The inkjet recording apparatus according to claim 8 , wherein the information for controlling the presence or absence of the recovery liquid includes information regarding the predicted value of the viscosity and / or the amount of the liquid in the porous body. .. The inkjet recording apparatus according to claim 8 or 9 , wherein the information for controlling the presence or absence of the recovery liquid includes information on the environment including temperature and / or humidity obtained by the environmental information acquisition apparatus. .. The information for controlling the presence or absence of the application of the recovery liquid includes information regarding the elapsed time from the completion of the application of the recovery liquid obtained by the elapsed time acquisition device to the liquid absorption process. Item 2. The inkjet recording apparatus according to any one of Items 8 to 10. The recorded object is a recording medium for forming a final image, and a second image on the recording medium in which at least a part of the aqueous liquid component is removed from the first image by the liquid absorbing member. The inkjet recording apparatus according to any one of claims 1 to 6, wherein the image is formed. The inkjet recording apparatus according to claim 12 , further comprising a recovery liquid application control unit that controls the presence or absence of the recovery liquid application by the recovery liquid application unit to the liquid absorption member. The inkjet recording apparatus according to claim 13 , wherein the information for controlling the presence or absence of the application of the recovery liquid includes information regarding the predicted value of the viscosity and / or the amount of the liquid in the porous body. .. The inkjet recording apparatus according to claim 13 or 14 , wherein the information for controlling the presence or absence of the application of the recovery liquid includes information on the environment including temperature and / or humidity obtained by the environmental information acquisition apparatus. .. The information for controlling the presence or absence of the application of the recovery liquid is characterized by including information regarding the elapsed time from the completion of the application of the recovery liquid obtained by the elapsed time acquisition device to the liquid absorption process. The inkjet recording apparatus according to any one of claims 13 to 15. The inkjet according to any one of claims 13 to 16 , wherein the information for controlling the presence or absence of the recovery liquid includes information regarding the type of the recording medium obtained by the recording medium information acquisition device. Recording device. Formed on the recording medium, an ink containing a water-soluble liquid medium and the coloring material reacts with the ink to impart a reaction liquid for thickening the ink, an ink image comprising the aqueous liquid component and a colorant Image formation unit and
A liquid absorbing member having a porous body that concentrates the ink constituting the ink image by absorbing at least a part of the aqueous liquid component from the ink image.
It is an inkjet recording device equipped with
A transport unit that repeatedly carries in and out of the liquid absorbing member into and out of the liquid absorbing processing region where the liquid absorbing treatment from the ink image by the liquid absorbing member is performed.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
A recovery liquid application control unit that intermittently applies the recovery liquid to the liquid absorption member by the recovery liquid application unit, and a recovery liquid application control unit.
An inkjet recording device characterized by the above. An ink containing an aqueous liquid medium and a coloring material and a reaction liquid for reacting with the ink to thicken the ink are applied to a recording body, and a first image containing the aqueous liquid component and the coloring material is obtained. The image forming unit to be formed and
From the first image, a liquid absorbing member having a porous body that absorbs at least a part of the aqueous liquid component,
With
The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. An inkjet recording apparatus in which the second image above is transferred to a recording medium for forming a final image.
A transport unit that repeatedly carries in and out of the liquid absorption member into and out of the liquid absorption treatment region where the liquid absorption treatment from the first image is performed by the liquid absorption member.
A recovery liquid applying portion that imparts the ink and a recovery liquid having a viscosity lower than that of the reaction liquid to the liquid absorption member carried out from the liquid absorption treatment region.
An inkjet recording apparatus comprising: a recovery liquid application control unit that controls the presence or absence of application of the recovery liquid by the recovery liquid application unit to the liquid absorption member. The inkjet recording apparatus according to claim 19, wherein the recovery liquid has a higher concentration of water than the reaction liquid and ink. The inkjet recording apparatus according to claim 19 or 20, wherein the recovery liquid has a lower vapor pressure than the reaction liquid and the ink. To the recording medium, an ink containing a water-soluble liquid medium and the coloring material, by applying a reaction liquid for thickening the ink reacts with the ink, first comprising an aqueous liquid component and the colorant Image formation process to form an image and
A liquid absorption treatment in which the first surface of the porous body of the liquid absorbing member is brought into contact with the first image, and at least a part of the aqueous liquid component is absorbed by the porous body from the first image. Is an inkjet recording method comprising a liquid absorption step of performing the above in a liquid absorption processing region.
A transfer step of retransmitting the porous body carried out from the liquid absorption treatment region to the liquid absorption treatment region, and
A recovery liquid application step of applying a recovery liquid having a viscosity lower than that of the ink and the reaction liquid to the first surface of the porous body before retransmission in the recovery liquid application unit.
Have a,
An inkjet recording method characterized in that the porous body is repeatedly used for the liquid absorption treatment in the liquid absorption step, and the recovery liquid application step is intermittently performed with respect to the repeated use of the porous body. It is further characterized by further comprising a wetting liquid applying step of applying a wetting liquid having a contact angle of less than 90 ° to the first surface of the porous body to the first surface of the porous body before retransmission. The inkjet recording method according to claim 22. The inkjet recording method according to claim 23 , wherein the recovery liquid applying step is the same step as the wetting liquid applying step. The inkjet recording method according to any one of claims 22 to 24 , wherein the recovery liquid has a higher concentration of water than the reaction liquid and the ink. The inkjet recording method according to any one of claims 22 to 25 , wherein the recovery liquid has a lower vapor pressure than the reaction liquid and the ink. Any one of claims 22 to 26, characterized in that it further comprises a passage conveying step of conveying the porous body retransmitted to the liquid absorption treatment area by passing through a liquid absorption treatment area to the recovery liquid application unit The inkjet recording method described in 1. The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. The inkjet recording method according to any one of claims 22 to 27 , wherein the second image is transferred to a recording medium for forming a final image. The inkjet recording method according to claim 28 , further comprising a recovery liquid application control step for controlling the presence or absence of the recovery liquid applied to the porous body in the recovery liquid application unit. The inkjet recording method according to claim 29 , wherein the information for controlling the presence or absence of the recovery liquid includes information regarding the predicted value of the viscosity and / or the amount of the liquid in the porous body. .. The inkjet recording method according to claim 29 or 30 , wherein the information for controlling the presence or absence of the recovery liquid includes information on the environment including temperature and / or humidity obtained by the environmental information acquisition device. .. The information for controlling the presence or absence of the application of the recovery liquid includes information regarding the elapsed time until the liquid absorption step after the completion of the recovery liquid application step obtained by the elapsed time acquisition device. Item 2. The inkjet recording method according to any one of Items 29 to 31. The recorded object is a recording medium for forming a final image, and a second image is formed on the recording medium from which at least a part of the aqueous liquid component is removed from the first image. Item 2. The inkjet recording method according to any one of Items 22 to 27. The inkjet recording method according to claim 33 , further comprising a recovery liquid application control step for controlling the presence or absence of application of the recovery liquid to the porous body in the recovery liquid application unit. The inkjet recording method according to claim 34 , wherein the information for controlling the presence or absence of the recovery liquid includes information regarding the predicted value of the viscosity and / or the amount of the liquid in the porous body. .. The inkjet recording method according to claim 34 or 35 , wherein the information for controlling the presence or absence of the recovery liquid includes information on the environment including temperature and / or humidity obtained by the environmental information acquisition device. .. The information for controlling the presence or absence of the application of the recovery liquid is characterized by including information regarding the elapsed time from the completion of the recovery liquid application step obtained by the elapsed time acquisition device to the liquid absorption step. The inkjet recording method according to any one of claims 34 to 36. The inkjet according to any one of claims 34 to 37 , wherein the information for controlling the presence or absence of the recovery liquid includes information regarding the type of the recording medium obtained by the recording medium information acquisition device. Recording method. A first image containing an aqueous liquid component and a coloring material by imparting an ink containing an aqueous liquid medium and a coloring material to a recording object and a reaction liquid for reacting with the ink to thicken the ink. And the image formation process to form
A liquid absorption treatment in which the first surface of the porous body of the liquid absorbing member is brought into contact with the first image, and at least a part of the aqueous liquid component is absorbed by the porous body from the first image. In the liquid absorption process, which is performed in the liquid absorption treatment area,
Have,
The recorded body is a transfer body that temporarily holds the first image and the second image in which at least a part of the aqueous liquid component is removed from the first image, and the transfer body is the transfer body. An inkjet recording method in which the second image above is transferred to a recording medium for forming the final image.
A transfer step of retransmitting the porous body carried out from the liquid absorption treatment region to the liquid absorption treatment region, and
A recovery liquid application step of applying a recovery liquid having a viscosity lower than that of the ink and the reaction liquid to the first surface of the porous body before retransmission in the recovery liquid application unit.
A recovery liquid application control step for controlling the presence or absence of application of the recovery liquid to the porous body in the recovery liquid application unit, and a recovery liquid application control step.
An inkjet recording method characterized by having. The inkjet recording method according to claim 39, wherein the recovery liquid has a higher concentration of water than the reaction liquid and ink. The inkjet recording method according to claim 39 or 40, wherein the recovery liquid has a lower vapor pressure than the reaction liquid and the ink.

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