JP5671817B2 - Image recording composition and recording apparatus - Google Patents

Description

  The present invention relates to an image recording composition and a recording apparatus.

  Patent Document 1 proposes a recording method in which a liquid is attached to the surface of an intermediate transfer member, an ink droplet is attached onto the liquid, and then the ink on the intermediate transfer member is transferred to the printing medium together with the liquid. Yes. In Patent Document 1, a liquid obtained by removing a dye or a pigment from the constituent material of the ink droplet is used as the liquid deposited on the intermediate transfer body prior to the ink droplet.

In Patent Document 2, a first material that reduces the fluidity of a colored ink containing a colorant is applied on an intermediate transfer member, and a colored ink is applied on the material to form an ink image, which is then formed on a recording medium. A recording method for transferring an ink image formed on the intermediate transfer member to a recording medium after applying a second material for improving the scratch resistance of the image to be printed has been proposed. A liquid containing a metal salt is used as the first material, and a liquid containing a water-soluble resin is used as the second material.
In Patent Document 3, using an intermediate transfer recording medium provided with an intermediate transfer layer made of an uncured ionizing radiation curable resin composition on one surface of a substrate, an arbitrary image is printed on the intermediate transfer layer, There has been proposed a method in which fine irregularities are formed on the surface of an intermediate transfer layer after the attached transfer layer is transferred onto the object to be cured, and cured with ionizing radiation.

Japanese Patent Application Laid-Open No. 2001-212956 JP 2005-170036 A JP 2006-76042 A

  The problem of the present invention is that after curing of the cured layer formed by the image recording composition, compared to the case of using the image recording composition not containing the silicone-modified urethane prepolymer having an ultraviolet curable functional group. It is an object of the present invention to provide an image recording composition having improved flexibility in the above layer.

The above problem is solved by the following means. That is,
The invention according to claim 1 is an image recording composition containing a liquid-absorbing component and a silicone-modified urethane prepolymer having an ultraviolet curable group.
The invention according to claim 2 is the image recording composition according to claim 1, wherein the liquid-absorbing component comprises a liquid-absorbing resin.

The invention according to claim 3 is the image recording composition according to claim 1 or 2 , further comprising a hydrophilic monomer having a solubility parameter of 9.7 or more.

Invention relates to an image recording composition according to any one of the silicone-modified urethane claims content of the prepolymer is in the range of 30 mass% or more 1 wt% 1-claim 3 according to claim 4 It is a thing.

The invention according to claim 5 is the image recording composition according to any one of claims 1 to 4 , further comprising a reactive silicone-modified polyol.

The invention according to claim 6 is the image recording composition according to any one of claims 1 to 5 , wherein the silicone-modified urethane prepolymer has a weight average molecular weight of 1000 or more and 30000 or less.

The invention according to claim 7, wherein the silicone-modified urethane prepolymer, image recording according to any one of claims 1 to 6 is a silicone-modified polyester urethane prepolymer or a silicone-modified polyether urethane prepolymer It is a composition.

The invention according to claim 8 is an intermediate transfer member, a supply device for supplying the image recording composition according to any one of claims 1 to 7 to the intermediate transfer member, and the intermediate transfer member. An ejection device that ejects droplets containing an aqueous solvent onto a cured layer formed of the image recording composition supplied to the recording medium, and records the cured layer ejected with the droplets from the intermediate transfer member. The recording apparatus includes a transfer device for transferring to a medium and an irradiation device for irradiating the cured layer with ultraviolet rays.

The invention according to claim 9 provides a supply device for supplying the image recording composition according to any one of claims 1 to 7 to a recording medium, and the image recording supplied to the recording medium. A recording apparatus comprising: a discharge device that discharges droplets containing an aqueous solvent to a cured layer formed of a composition; and an irradiation device that irradiates ultraviolet rays onto the cured layer onto which the droplets have been discharged. is there.

  According to the first aspect of the present invention, compared to the case where an image recording composition not containing a silicone-modified urethane prepolymer having an ultraviolet curable functional group is used, the cured product formed by the image recording composition. There is an effect that an image recording composition having improved flexibility in the layer after curing of the layer is provided.

According to the invention of claim 3 , compared with the case where the hydrophilic monomer of the present invention is not further contained, the adhesiveness to the recording medium in the cured layer of the cured layer formed by the image recording composition is increased. Is improved.

According to the fourth aspect of the present invention, compared to the case where the content of the silicone-modified urethane prepolymer is outside the specified range of the present invention, the image formed on the cured layer formed by the image recording composition There is an effect that the image quality can be improved.

According to the fifth aspect of the present invention, it is possible to suppress the density unevenness of the image formed on the cured layer formed of the image recording composition as compared with the case where the reactive silicone-modified polyol is not further included. There is an effect.

According to the invention of claim 6 , the image formed on the cured layer formed of the image recording composition is compared with the case where the weight average molecular weight of the silicone-modified urethane prepolymer is outside the scope of the present invention. There is an effect that density unevenness can be suppressed.

According to the invention of claim 7 , compared with the case of using a silicone-modified urethane prepolymer other than the silicone-modified polyester urethane prepolymer and the silicone-modified polyether urethane prepolymer, there is little discoloration due to yellowing and weather resistance, There is an effect that there is little alteration by ink.
According to the invention of claim 8 and claim 9, in comparison with the case of not using the image recording composition according to any one of claims 1 to 7, flexibility enhanced image There is an effect that an image is formed using the recording composition.

It is also a schematic diagram showing an example of a recording apparatus according to the present embodiment. It is a schematic diagram which shows an example of the recording device which concerns on this Embodiment. It is a schematic diagram which shows an example of the recording device which concerns on this Embodiment. It is a schematic diagram which shows an example of the recording device which concerns on this Embodiment.

  Hereinafter, the image recording composition and recording apparatus of the present embodiment will be described in detail.

<Image recording composition>
The image recording composition according to the present embodiment comprises a liquid-absorbing component , a silicone-modified urethane prepolymer having an ultraviolet curable group, and a cured layer formed by discharging droplets containing an aqueous solvent. For image recording.

According to the image recording composition of the present embodiment, the layer to be cured formed of the image recording composition has a recording medium containing a silicone-modified urethane prepolymer having an ultraviolet curable group. Even after it is transferred to the surface and cured by ultraviolet irradiation, a cured layer with improved flexibility can be obtained compared to the case of using the image-recording composition not containing the silicone-modified urethane prepolymer. Conceivable.
In the present embodiment, a layer obtained by curing a layer to be cured by ultraviolet irradiation is referred to as a “cured layer”.

  Subsequently, each component which comprises the composition for image recording which concerns on this embodiment is demonstrated in detail.

(Silicone-modified urethane prepolymer having an ultraviolet curable group)
As described above, the image recording composition of the present embodiment contains a silicone-modified urethane prepolymer having an ultraviolet curable group. The silicone-modified urethane prepolymer having an ultraviolet curable group functions as a curable material that is cured by irradiation with ultraviolet rays in the image recording composition.
As described above, since the image recording composition of the present embodiment contains the silicone-modified urethane prepolymer having an ultraviolet curable group together with the liquid-absorbing resin particles, the cured layer formed of the image recording composition. Will have ink absorption and curability in a single layer. For this reason, interfacial peelability is suppressed by using a plurality of layers (for example, providing a separate release layer) as compared with the case where ink absorbability and curability are realized.
In addition, polymers having a urethane bond have flexibility and hydrogen bonding. Therefore, even when a monomer is added to the image recording composition, the image recording composition of the present embodiment contains a silicone-modified urethane prepolymer having an ultraviolet curable group. The distortion of the cured layer formed by the composition is alleviated.
Although details will be described later, by adjusting the molecular weight of the silicone-modified urethane prepolymer having an ultraviolet curable group used in the present embodiment to an appropriate range (1000 to 30000, details will be described later) When the cured layer formed of the composition is cured by ultraviolet rays, the silicone-modified urethane prepolymer having the ultraviolet curable group contributes to the suppression of increase in viscosity of the image recording composition.

  Hereinafter, the “silicone-modified urethane prepolymer having an ultraviolet curable group” will be simply referred to as “silicone-modified urethane prepolymer”.

The silicone-modified urethane prepolymer used in the image recording composition of the present embodiment can be obtained by modifying a urethane prepolymer with a silicone component.
In this embodiment, “prepolymer” indicates a polymer in a state before being cured by ultraviolet irradiation.

  Examples of the urethane prepolymer include polyester urethane prepolymer, polyether urethane prepolymer, polyetherester urethane prepolymer, and polycarbonate urethane prepolymer. Of these, polyester urethane prepolymer or polyether urethane prepolymer is desirable from the viewpoint of ink affinity.

In addition, as a commercial item of a urethane prepolymer, a bi- or trifunctional acrylate derivative, an isosinurate derivative, a trimethylolpropane derivative, etc. are mentioned.
Examples of the content of the urethane prepolymer in the silicone-modified urethane brepolymer include 10 mol% to 50 mol%, and 15 mol% to 30 mol%.

  As a silicone component used for modification | denaturation of the said urethane prepolymer, the polymer which has 10 to 50 mol% of dimethylsiloxane units is mentioned, for example. Specifically, as the silicone component, polyether-modified dimethylsiloxane having a urethane side chain, polypropylene glycol, and a surface tension of 20 mN / m to 30 mN / m and HLB = 8 to 18 in the range. Examples thereof include polyethylene glycol-modified dimethylsiloxane having a side chain or a main chain and having an affinity for ink in a hydrophilic to weakly hydrophilic region.

  In addition, as a commercial item of a silicone component, a trifunctional isocyanuric acid derivative such as Degussa TEGO2200N Osaka Organic Chemical Co., Ltd., trifunctional acrylate CN990, Dainichi Seika) sp005, Shinetsu Chemical Co., Ltd.) bifunctional polyether-modified dimethylsiloxane X22 And the like.

  Examples of the weight average molecular weight of the silicone component include a range of several hundreds to 10,000 and 1,000 to 5,000.

  Examples of the silicone component content in the silicone-modified urethane brepolymer include 10 mol% or more and 50 mol% or less, and 15 mol% or more and 30 mol% or less.

As a method for modifying the urethane prepolymer with a silicone component, (A) an acrylic polyol compound, an organopolysiloxane compound having a hydroxyl group at a terminal, and a polyisocyanate compound are mixed and applied, and the hydroxyl groups of the acrylic polyol compound are mixed. Or a carboxyl group in the side chain by adding an unsaturated carboxylic acid such as acrylic acid or methacrylic acid as a copolymerization component. Silicone-modified acrylic polyol compound in which the carboxyl group of the introduced acrylic polyol is bonded to the hydroxyl group of the organopolysiloxane compound having a hydroxyl group at the terminal by an esterification reaction, and an organopolysiloxy group is introduced into the side chain Obtained, and thereafter, between its hydroxyl group, a method for crosslinking through the polyisocyanate compound, and the like.
In addition, as a method of modifying the urethane prepolymer with a silicone component, a urethane-modified acrylate obtained by adding an organosiloxane derivative to a monomer having a hydroxyl group at the terminal, such as isocyanuric acid diacrylate, may be used. The method of this is also mentioned.

  The silicone-modified urethane prepolymer obtained by modifying the urethane prepolymer has an ultraviolet curable group.

  Examples of the ultraviolet curable group include at least one selected from the group consisting of an acryl group, a methacryl group, and monomers having these functional groups. Among these, as the ultraviolet curable group, it is desirable to use an acrylic group-containing monomer for reasons of reactivity and flexibility.

The ultraviolet curable group is preferably introduced at the terminal of the silicone chain contained in the silicone-modified urethane prepolymer. The number of ultraviolet curable groups in the silicone-modified urethane prepolymer is preferably 2 or more (bifunctional or more), and more preferably 3 or more (trifunctional or more).
As the number of functional groups of the silicone-modified urethane prepolymer increases, crosslinking proceeds in the image recording composition, but the reactivity with other monomers contained in the image recording composition is considered to decrease. For this reason, when a tetrafunctional to hexafunctional polyfunctional monomer is used as a monomer to be added to the image recording composition containing the silicone-modified urethane prepolymer, a large amount of these monomers cannot be added. That is, in order to balance the flexibility of the cured layer formed from the image recording composition and the reactivity in the cured layer (in the image recording composition), a monomer having an appropriate number of functional groups is used. It is desirable to use it mixed with the recording composition.

  As a method for introducing the ultraviolet curable group into the silicone chain, a method of introducing a polyether by side chain alkyl esterification may be used.

In addition, the silicone-modified urethane prepolymer in the present embodiment, the main side chain portion of the silicone, or the side chain of the urethane portion, at least one of a polyoxyethylene chain and a polyoxypropylene chain, these block copolymers, Or what has a monomer etc. which have a urethane bond is desirable.
By having at least one of these polyoxyethylene chains and polyoxypropylene chains, these block copolymers, or monomers having a urethane bond in the side chain, the silicone-modified urethane prepolymer can be used as a surfactant. Will also work.
In addition, the silicone-modified urethane prepolymer of the present embodiment is included by having at least one of these polyoxyethylene chains and polyoxypropylene chains in the side chain and adjusting the type and molecular weight of the side chain. The flexibility of the cured layer formed by the image recording composition, the internal strain, the retainability of the ink added to the cured layer, the monomer in the cured layer and the silicone-modified urethane prepolymer It is possible to adjust the compatibility and the curing rate of the cured layer.
In addition, as a repeating number of the polyoxyethylene in this polyoxyethylene chain, and a repeating number of the polyoxypropylene in a polyoxypropylene chain, 1 or more and 1000 or less are mentioned, for example.

The weight average molecular weight of the silicone-modified urethane prepolymer is preferably 1000 or more and 30000 or less, more preferably 1000 or more and 10,000 or less, and particularly preferably 1000 or more and less than 5000.
By setting the weight average molecular weight of the silicone-modified urethane prepolymer within the above range, ink droplets described later are applied to the cured layer formed by the image recording composition containing the silicone-modified urethane prepolymer. Even after the image is formed on the cured layer, it is considered that the decrease in the reactivity (ultraviolet curable property) of the silicone-modified urethane prepolymer is suppressed.

  The weight average molecular weight is measured by gel permeation chromatography (GPC). The molecular weight measurement by GPC was carried out using a Tosoh GPC / HLC-8120 as a measuring device, a Tosoh column / TSKgel GMHHR-M + TSKgel GMHHR-M (7.8 mm ID 30 cm), and a chloroform solvent. The weight average molecular weight is calculated from the measurement result using a molecular weight calibration curve prepared with a monodisperse polystyrene standard sample. Hereinafter, the weight average molecular weight is measured by this method.

Specific examples of the silicone-modified urethane prepolymer used in the present embodiment include a linear polyester urethane acrylate composed of an aliphatic isocyanate component and a bifunctional or higher acrylic component, among which isocyanurate structure. Polypropylene glycol units and polyethylene glycol diols having a polyether urethane moiety terminated with a polyfunctional urethane acrylate group having a diol are desirable.
As the commercially available products of the silicone-modified urethane prepolymer, Osaka Organic Chemical Industry Co., Ltd. of CN990, produced by BYK Japan KK of UV3500, Shin-Etsu Chemical Co., Ltd. of X22, and the like Dainichi Seika Co. Sp005.

Examples of the content of the silicone-modified urethane prepolymer in the image recording composition of the present embodiment include 1% by mass to 30% by mass, or 1% by mass to 10% by mass.
When the content of the silicone-modified urethane prepolymer in the image recording composition is within the above range, the cured layer formed of the image recording composition containing the silicone-modified urethane prepolymer is cured by ultraviolet irradiation. It is considered that the flexibility in the later effect layer is improved. Further, when the content of the silicone-modified urethane prepolymer in the image recording composition is within the above range, reaction inhibition of other monomers contained in the image recording composition is suppressed, and the monomers It is considered that the decrease in the ability to form a copolymer is suppressed. It is also considered that the image quality of the image formed on the cured layer can be improved.

The surface tension of the silicone-modified urethane prepolymer should be adjusted in the range of 20 mN / m or more and 30 mN / m or less, for example, from the viewpoint of suppressing increase in viscosity of the image recording composition and suppressing decrease in water resistance. Is good.
This surface tension may be adjusted by the weight average molecular weight of the silicone-modified urethane prepolymer, the polyol skeleton, its molecular weight, functional group, silicone-modified species, and the like.

(Liquid absorption component)
Next, the liquid absorption component will be described.

  The image recording composition contains a liquid-absorbing component that absorbs ink as a material for fixing the colorant in the ink. This liquid-absorbing component contains a liquid-absorbing material as a main component. The “main component” refers to a component containing 50% by mass or more based on the whole. The liquid absorbing material means that the liquid absorbing material and the ink are mixed at a weight ratio of 30: 100 for 24 hours, and then the weight of the liquid absorbing material is equal to the weight of the liquid absorbing material when the liquid absorbing material is taken out from the mixed solution with a filter. It is increased by 5% or more compared with that before mixing.

Examples of the liquid-absorbing material include a resin containing sodium acrylate and sodium sulfonate (hereinafter sometimes referred to as liquid-absorbing resin), and inorganic particles having surface affinity (for example, silica and alumina). , Porous zeolite, etc.), and the like, which are appropriately selected according to the ink used.
Specifically, when water-based ink is used as the ink, it is desirable to use a water-absorbing material as the liquid-absorbing material. When oil-based ink is used as the ink, it is desirable to use an oil-absorbing material as the liquid-absorbing material.

  Specific examples of the water-absorbing material include polyacrylic acid and salts thereof, polymethacrylic acid and salts thereof, (meth) acrylic acid ester- (meth) acrylic acid and salts thereof, and styrene. -Copolymer composed of (meth) acrylic acid and its salt, styrene- (meth) acrylic ester-Copolymer composed of (meth) acrylic acid and its salt, styrene- (meth) acrylic ester A copolymer composed of an ester formed from an alcohol having an aliphatic or aromatic substituent having a carboxylic acid and a salt structure thereof and (meth) acrylic acid, (meth) acrylic acid ester-carboxylic acid and a salt thereof Copolymer composed of ester formed from alcohol having aliphatic or aromatic substituent having structure and (meth) acrylic acid Copolymer composed of ethylene- (meth) acrylic acid copolymer, butadiene- (meth) acrylic ester- (meth) acrylic acid and salts thereof, butadiene- (meth) acrylic ester-carboxylic acid and salts thereof A copolymer composed of an ester formed from an alcohol having an aliphatic or aromatic substituent having a structure and (meth) acrylic acid, a polymaleic acid and a salt thereof, a copolymer composed of styrene-maleic acid and a salt thereof Examples thereof include sulfonic acid-modified products of the respective resins, phosphoric acid-modified products of the respective resins, and the like, preferably from polyacrylic acid and salts thereof, styrene- (meth) acrylic acid and salts thereof. Consists of copolymer, styrene- (meth) acrylic acid ester- (meth) acrylic acid and its salts A copolymer composed of an ester produced from (meth) acrylic acid, an alcohol having an aliphatic or aromatic substituent having a styrene- (meth) acrylic acid ester-carboxylic acid and a salt structure thereof, and (Meth) acrylic acid ester- (meth) acrylic acid and a copolymer composed of a salt thereof. These resins may be uncrosslinked or crosslinked.

  Specific examples of the oil-absorbing material include low-molecular gelling agents such as hydroxystearic acid, cholesterol derivatives, and benzylidene sorbitol, polynorbornene, polystyrene, polypropylene, styrene-butadiene copolymers, and various rosins. Desirably, polynorbornene, polypropylene, and rosins are used.

  The liquid-absorbing component may be in the form of solid particles, or it may be in a state where the liquid is dispersed in the cured layer, such as an emulsion, or in a semi-dissolved state (for example, the polymer chain is broken and the molecular chain is extended) State and partially compatible state of low molecular components).

  The diameter (volume average particle diameter) of the liquid-absorbing component is preferably in the range of 0.05 μm to 25 μm, and more preferably 0.05 μm to 5 μm.

  The specific gravity of the liquid-absorbing component is preferably relatively smaller than the specific gravity of the curable material contained in the image recording composition. The ratio of the liquid-absorbing component to the entire image recording composition is preferably 1% or more and 60% or less, more preferably 10% or more and 50% or less, and even more preferably 20% or more and 40% or less in terms of mass ratio. .

  When the liquid-absorbing component is a resin particle containing a liquid-absorbing material, the resin particles can be prepared, for example, by pulverizing a resin containing the liquid-absorbing material with a ball mill, sand mill, vibration mill, attritor mill, etc. (Sieving, filtering) and the like.

(Other materials included in image recording composition)
The image recording composition of the present embodiment may have a configuration in which the following materials are further added to the above-described silicone-modified urethane prepolymer and liquid-absorbent resin particles.

  First, the hydrophilic monomer that is desirably contained in the image recording composition will be described.

The image recording composition preferably further contains a hydrophilic monomer having a solubility parameter (sp value) of 9.7 or more and less than 14, and more preferably contains one or more hydrophilic monomers of 9.7 or more and less than 13.
The total content of the hydrophilic monomer exhibiting the sp value in the image recording composition is preferably in the range of 1% by mass to 60% by mass, and in the range of 5% by mass to 50% by mass. It is particularly desirable that

When the composition for image recording contains a hydrophilic monomer having a solubility parameter (sp value) of 9.7 or more and less than 14, improvement in adhesion of the cured layer to the recording medium, improvement in ink absorbability, It is thought that the reactivity at the time of fixation can be improved.

  A hydrophilic monomer having a solubility parameter in the above range may be used as a mixture of one or more. However, the hydrophilic monomer is preferably monofunctional, bifunctional, or trifunctional, and monofunctional or bifunctional. It is further desirable to be functional. Since the monofunctional, bifunctional, or trifunctional hydrophilic monomer is contained in the image recording composition, aggregation of the liquid-absorbing resin particles contained in the image recording composition is suppressed, and image recording is performed. It is considered that the increase in viscosity of the composition for use is suppressed. For this reason, it is thought that the dispersion | variation in the layer thickness of the to-be-hardened layer formed with the composition for image recording is suppressed.

Functional groups contained in this hydrophilic monomer include acrylamide derivatives, cyclic amides, alkylamides, polyethylene glycol diacrylates (such as PEG400, 600, 1000, ethoxyphenyl acrylate, 1,6-hexanediol diacrylate, tricyclodecane. Methanol diacrylate, trimethylolpropane triacrylate, acroyl morphylline, vinyliliformamide, hydroxyethyl alkylamide, acrylic acid and copolymers, hydroxyacrylpropyl (or butyl, hexyl, etc.) methacrylates and acrylates, pentaerythritol tris Acrylate, pentaerythritol tetraacrylate, among which cyclic acroyl morphylin, PGE400 diacrylate, hydroxy Sihexyl acrylate is preferred.

  Hereinafter, an example of a hydrophilic monomer having an sp value of 9.7 or more and less than 14 is shown below. The numbers in () are sp values. The sp value is determined from the structural formula of the compound by the fedors method.

  Tricyclodecane methanol diacrylate (9.7), trimethylolpropane triacrylate (9.9), acroylmorphylline (10.9), vinyliliformamide (13.5), hydroxyethylacramide (10 .6), acrylic acid (11.1) and copolymers, hydroxyacryloyloxypropyl methacrylate (11.7), pentaerythritol triacrylate (11.5), pentaerythritol tetraacrylate (10.3) ) And the like. Acrylic acid comonomers and oligomers such as urethane acryl, polyether derivatives and polyester derivatives having excellent flexibility may be used in combination.

  In addition to the above components, the image recording composition preferably further contains a reactive silicone-modified polyol from the viewpoint of improving the image quality of the image recorded on the cured layer.

  Specific examples of the reactive silicone-modified polyol include amino modification, epoxy modification, carboxyl group modification, carbinol modification, methacryl modification, mercapto modification, phenol modification, and one end of these, different functional group modification, and the like. It is done.

  The content of the reactive silicone-modified polyol in the image recording composition is such that the total amount with the silicone-modified urethane prepolymer contained in the image recording composition ranges from 1% by mass to 30% by mass. It is desirable to be prepared in the range of 5% by mass or more and 20% by mass or less.

  As described above, the above-mentioned silicone-modified urethane prepolymer functions as a curable material that is cured by irradiation with ultraviolet rays. However, the image recording composition further includes the following curable material as a curable material. May be added.

  Examples of the curable material include an ultraviolet curable monomer, an ultraviolet curable macromer, an ultraviolet curable oligomer, and an ultraviolet curable prepolymer.

  Examples of the ultraviolet curable monomer include alcohol / polyhydric alcohol / amino alcohol acrylic esters, alcohol / polyhydric alcohol methacrylates, acrylic aliphatic amides, acrylic alicyclic amides, and acrylic aromatic amides. Radical curable materials such as cation; cation curable materials such as epoxy monomers, oxetane monomers, vinyl ether monomers; and the like. Examples of the ultraviolet curable macromer, the ultraviolet curable oligomer, and the ultraviolet curable prepolymer include those obtained by polymerizing these monomers at a predetermined polymerization degree, epoxy, urethane, polyester, polyether skeleton, acryloyl group, Examples include radical curable materials such as epoxy acrylate, urethane acrylate, polyester acrylate, polyether acrylate, urethane methacrylate, and polyester methacrylate to which a methacryloyl group is added.

  The curable material contained in the image recording composition is desirably a silicone-modified silicone compound.

  The image recording composition preferably contains an ultraviolet polymerization initiator for allowing the ultraviolet curing reaction to proceed. Furthermore, the image recording composition may contain a reaction aid, a polymerization accelerator and the like for further proceeding the polymerization reaction, if necessary.

When the ultraviolet curing reaction in the image recording composition proceeds by a radical reaction, examples of the ultraviolet polymerization initiator include benzophenone, thioxanthone, benzyldimethyl ketal, α-hydroxyketone, α-hydroxyalkylphenone, α- Examples include amino ketone, α-aminoalkylphenone, monoacylphosphine oxide, bisacylphosphine oxide, hydroxybenzophenone, aminobenzophenone, titanocene type, oxime ester type, and oxyphenylacetate type.
When the ultraviolet curing reaction in the image recording composition proceeds by a cation reaction, examples of the ultraviolet polymerization initiator include arylsulfonium salts, aryldiazonium salts, diaryliodonium salts, triarylsulfonium salts, and allene-ion complexes. Examples thereof include derivatives and triazine initiators.

  As described above, the silicone-modified urethane prepolymer contained in the image recording composition functions as a surfactant by preparing a substituent or the like, but the image recording composition further includes Further, a surfactant such as a nonionic surfactant or an anionic surfactant may be contained. However, it is necessary to adjust the surface tension of the image recording composition within the range of 20 mN / m or more and 50 mN / m or less so as not to inhibit the ultraviolet curing ability of the entire image recording composition (cured layer). is there.

  Nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene fatty acid esters, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, poly Oxyethylene glycerin fatty acid ester, polyglycerin fatty acid ester, sucrose fatty acid ester, polyoxyethylene alkylamine, polyoxyethylene fatty acid amide, alkyl alkanolamide, polyethylene glycol polypropylene glycol block copolymer, acetylene glycol, polyoxyethylene adduct of acetylene glycol Etc.

  Examples of the anionic surfactant include alkyl benzene sulfonate, alkyl phenyl sulfonate, alkyl naphthalene sulfonate, higher fatty acid salt, sulfate of higher fatty acid ester, sulfonate of higher fatty acid ester, higher alcohol ether. Sulfate esters and sulfonates, higher alkyl sulfosuccinates, polyoxyethylene alkyl ether carboxylates, polyoxyethylene alkyl ether sulfates, alkyl phosphates, polyoxyethylene alkyl ether phosphates, etc. Desirably, dodecylbenzenesulfonate, isopropylnaphthalenesulfonate, monobutylphenylphenol monosulfonate, monobutylbiphenylsulfonate, dibutylphenylphenol disulfonate, etc. It is below.

  The surfactant is used, for example, in the range of 0.01% by mass to 10% by mass with respect to the image recording composition.

  The image recording composition according to this embodiment may be mixed with wax or rubber-like substances.

  Further, the image recording composition according to the present embodiment may further include a component for immobilizing the ink component on or inside the cured layer (hereinafter sometimes referred to as “immobilization component”). Good.

  Examples of the immobilization component include, but are not limited to, a component that adsorbs an ink component (for example, a coloring material) and a component that aggregates or thickens an ink component (for example, a coloring material). .

  Further, the image recording composition may contain water or an organic solvent for dissolving or dispersing the component contributing to the curing reaction.

  The image recording composition may contain various color materials for the purpose of controlling the color of the cured layer.

  In addition, the image recording composition may contain a thermoplastic resin for the purpose of adjusting the viscosity. Examples of the thermoplastic resin include acrylic resin, polyester resin, polycarbonate resin, polyurethane resin, polystyrene, polyether resin, polyethylene resin, polypropylene resin, polystyrene and its acrylic monomer copolymer and blends thereof. It is done.

  Examples of the surface tension of the image recording composition of the present embodiment include a range of 20 mN / m to 50 mN / m.

The image recording composition is used in this embodiment with a viscosity of 5 mPa · s to 30000 mPa · s, and the viscosity of the image recording composition is preferably higher than the viscosity of the ink.
The viscosity is a value measured by the following method, and the viscosity described in the present specification is a value measured by the following method.
As a viscometer, TV-22 (manufactured by Toki Sangyo Co., Ltd.) was used, and the viscosity (mPa · s) at 15 ° C. was measured at a shear rate = 2.25 to 750 (1 / s). In addition, it is a thing of the description speed 10s- ¹ in this specification.

  The image recording composition is preferably low-volatile or non-volatile at room temperature (25 ° C.). Here, low volatility means that the boiling point is 200 ° C. or higher under atmospheric pressure. Nonvolatile means that the boiling point is 300 ° C. or higher under atmospheric pressure.

(ink)
Next, the ink used in this embodiment will be described in detail. This ink corresponds to a droplet discharged to the cured layer in the recording apparatus of the present invention.
The ink can be used for both water-based ink and oil-based ink, but water-based ink is used from the viewpoint of environment. Aqueous ink (hereinafter simply referred to as ink) contains an ink solvent (for example, water, a water-soluble organic solvent) in addition to the recording material. In addition, other additives may be included as necessary.

  First, the recording material will be described. As the recording material, a color material is mainly used. As the color material, either a dye or a pigment can be used, but a pigment is preferable. As these coloring materials, known materials may be used.

  Other recording materials include hydrophilic anionic dyes, direct dyes, cationic dyes, reactive dyes, dyes such as polymer dyes and oil-soluble dyes, wax powders / resin powders and emulsions colored with dyes, Fluorescent dyes and fluorescent pigments, infrared absorbers, ultraviolet absorbers, magnetic materials such as ferromagnetic materials represented by ferrite and magnetite, semiconductors and photocatalysts represented by titanium oxide and zinc oxide, and other organic and inorganic electrons Examples include material particles.

  The content (concentration) of the recording material is, for example, in the range of 5% by mass to 30% by mass with respect to the ink.

Examples of the volume average particle diameter of the recording material include a range of 10 nm to 1000 nm.
The volume average particle diameter of the recording material refers to the particle diameter of the recording material itself, or the particle diameter to which the additive has adhered when an additive such as a dispersant is attached to the recording material. A Microtrac UPA particle size analyzer 9340 (manufactured by Leeds & Northrup) was used as the volume average particle diameter measuring apparatus. The measurement was performed according to a predetermined measurement method with 4 ml of ink placed in a measurement cell. As input values at the time of measurement, the viscosity of the ink was used as the viscosity, and the density of the dispersed particles was used as the density of the recording material.

  Next, the water-soluble organic solvent will be described. As the water-soluble organic solvent, polyhydric alcohols, polyhydric alcohol derivatives, nitrogen-containing solvents, alcohols, sulfur-containing solvents and the like are used.

  At least one kind of water-soluble organic solvent may be used. The content of the water-soluble organic solvent is, for example, in the range of 1% by mass to 70% by mass.

  Next, water will be described. As water, it is desirable to use ion-exchanged water, ultrapure water, distilled water, and ultrafiltered water from the viewpoint of preventing impurities from being mixed.

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

  Examples of these surfactants include various anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and the like. Desirably, anionic surfactants and nonionic surfactants are used. An activator is used.

  In addition, the ink contains other components such as penetrants for the purpose of adjusting the penetrability, polyethyleneimine, polyamines, polyvinylpyrrolidone, polyethylene glycol, ethylcellulose, carboxymethylcellulose, etc. In order to adjust pH, compounds of alkali metals such as potassium hydroxide, sodium hydroxide, lithium hydroxide, etc., pH buffer, antioxidant, antifungal agent, viscosity adjuster, conductive agent as necessary Further, an ultraviolet absorber, a chelating agent and the like are also added.

  Next, preferred characteristics of the ink will be described. First, the surface tension of the ink is, for example, in the range of 20 mN / m to 45 mN / m.

  Here, as the surface tension, a value measured in an environment of 23 ° C. and 55% RH using a Wilhelmy type surface tension meter (manufactured by Kyowa Interface Science Co., Ltd.) was adopted.

Examples of the viscosity of the ink include a range of 1.5 mPa · s to 30 mPa · s. Here, as the viscosity, a value measured using a rheomat 115 (manufactured by Contraves) as a measuring device under the conditions of a measurement temperature of 23 ° C. and a shear rate of 1400 s ⁻¹ was adopted.

  The ink is not limited to the above configuration. In addition to the recording material, for example, a functional material such as a liquid crystal material or an electronic material may be included.

<Recording device>
Next, a recording apparatus to which the image recording composition of the present embodiment is applied will be described.
The recording apparatus according to the present embodiment is formed by an intermediate transfer member, a supply device that supplies the above-described image recording composition onto the intermediate transfer member, and the image recording composition supplied onto the intermediate transfer member. The curing device is cured by irradiating ultraviolet rays to the ejection device that ejects the ink to the cured layer, the transfer device that transfers the cured layer from which the ink has been ejected to the recording medium. An irradiating device.

  Further, another aspect of the recording apparatus according to the present embodiment is formed by a supply device that supplies the above-described image recording composition onto a recording medium, and the image recording composition that is supplied onto the recording medium. The cured layer includes an ejection device that ejects the ink, and an irradiation device that cures the cured layer by irradiating ultraviolet rays.

  Next, the recording apparatus according to the present embodiment will be described with reference to the drawings. In addition, the same code | symbol is provided to the member which has the same function through all the drawings, and the overlapping description may be abbreviate | omitted.

  FIG. 1 is a configuration diagram illustrating a recording apparatus according to the first embodiment.

  As shown in FIG. 1, the recording apparatus 101 according to the first embodiment includes, for example, an intermediate transfer drum (intermediate transfer member) 10, an anionic liquid absorbing material on the intermediate transfer drum 10, and external stimulation (energy). A solution supply device 12 for supplying the image recording composition 12A containing at least a curable resin precursor that is cured by the above-described method to form a cured layer 12B formed of the image recording composition 12A; and a cured layer 12B An ink jet recording head 14 for ejecting ink droplets 14 </ b> A to form an image T, and a cured layer 12 </ b> B on which the image T is formed by applying a pressure by superimposing the recording medium P on the intermediate transfer drum 10 is disposed on the recording medium P. And a irradiating device 18 for supplying a curing stimulus for irradiating the cured layer 12B transferred onto the recording medium P with ultraviolet rays. To have.

  Further, downstream of the transfer device 16 in the rotation direction of the intermediate transfer drum 10, removal of the residue of the cured layer 12B remaining on the surface of the intermediate transfer drum 10 and foreign matters other than the residue (paper dust of the recording medium P, etc.) A cleaning device 20 for removing the deposits such as) is disposed.

The intermediate transfer drum 10 may have a configuration including, for example, a cylindrical substrate and a surface layer coated on the surface of the substrate. The intermediate transfer drum 10 has a width (length in the axial direction) equal to or greater than the width of the recording medium P.
Examples of the material of the cylindrical base include aluminum, stainless steel (SUS), and copper.
Examples of the material for the surface layer include various resins [for example, polyimide, polyamideimide, polyester, polyurethane, polyamide, polyethersulfone, fluorine resin, etc.], various rubbers (for example, nitrile rubber, ethylene propylene rubber, Chloroprene rubber, isoprene rubber, styrene rubber, butadiene rubber, butyl rubber, chlorosulfonated polyethylene, urethane rubber, epichlorohydrin rubber, acrylic rubber, silicone rubber, fluorine rubber, etc.). The surface layer may have a single layer structure or a stacked structure.

  The solution supply device 12 includes, for example, a supply roller 12D that supplies the image recording composition 12A to the intermediate transfer drum 10 in a housing 12C that stores the image recording composition 12A, and the supplied image recording composition. And a blade 12E that defines the layer thickness of the layer to be cured 12B formed by the object 12A.

  The solution supply device 12 may be configured such that the supply roller 12 </ b> D continuously contacts the intermediate transfer drum 10 or is separated from the intermediate transfer drum 10. Alternatively, the solution supply device 12 may supply the image recording composition 12A to the housing 12C from an independent solution supply system (not shown) so that the supply of the image recording composition 12A is not interrupted.

  The solution supply device 12 is not limited to the above-described configuration, and a known supply method (coating method: for example, bar coater coating, spray coating, ink jet coating, air knife coating, blade coating, roll coating) An apparatus using a method such as application) is applied.

  The inkjet recording head 14 includes, for example, a recording head 14K for discharging black ink, a recording head 14C for discharging cyan ink, and a magenta ink from the upstream side in the rotation direction of the intermediate transfer drum 10. The recording head 14 </ b> M and the recording head 14 </ b> Y for ejecting yellow ink are configured to include recording heads for each color. Of course, the configuration of the recording head 14 is not limited to the above configuration, and may be configured by only the recording head 14K, or may be configured by only the recording head 14C, the recording head 14M, and the recording head 14Y.

  For example, a line type ink jet recording head having a width equal to or larger than the width of the recording medium P is used for each recording head 14, but a conventional scanning ink jet recording head may be used. The ink ejection method of each recording head 14 is not limited as long as it is a method capable of ejecting ink, such as a piezoelectric element driving type and a heating element driving type.

  For example, the recording heads 14 are arranged in series in the order of the recording head 14K, the recording head 14C, the recording head 14M, and the recording head 14Y from the upstream side in the rotation direction of the intermediate transfer drum 10.

  Each recording head 14 is arranged such that the distance between the surface of the intermediate transfer drum 10 and the nozzle surface of the head is, for example, about 0.3 to 0.7 mm. Each recording head 14 is disposed, for example, such that its longitudinal direction intersects (preferably orthogonally intersects) the rotational direction of the intermediate transfer drum.

  The transfer device 16 includes a pressure roll 16 </ b> A disposed so as to be pressed against the intermediate transfer drum 10. The pressure roll 16 </ b> A is configured as in the material configuration of the intermediate transfer drum 10, for example.

  The irradiation device 18 is an ultraviolet irradiation device that irradiates the image recording composition 12A (the cured layer 12B formed thereby) with ultraviolet rays.

  As this ultraviolet irradiation device, for example, a metal halide lamp, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a deep ultraviolet lamp, a lamp that uses a microwave to excite a mercury lamp from the outside without electrode, an ultraviolet laser, a xenon lamp, a UV-LED, etc. are applied. Is done.

  The ultraviolet irradiation condition is not particularly limited as long as the image recording composition 12A (the cured layer 12B formed thereby) is cured. For example, the high pressure mercury lamp 120 W / cm output density is 2 Irradiate for 2 seconds.

  Each cured state refers to a state in which permeable paper (plain paper) is superimposed on the cured layer obtained by curing the layer to be cured 12B by the irradiation device 18 and no transfer occurs even when a load of 200 g is applied.

  As the recording medium P, a permeation medium (for example, plain paper, coated paper, etc.) and a non-penetration medium (for example, art paper, resin film, etc.) are applied. The recording medium is not limited to these, and includes other industrial products such as semiconductor substrates.

  Hereinafter, an image recording process of the recording apparatus 101 according to the present embodiment will be described.

  In the recording apparatus 101 according to this embodiment, the intermediate transfer drum 10 is rotationally driven, and first, the image recording composition 12A is supplied to the surface of the intermediate transfer drum 10 by the solution supply apparatus 12 to form the cured layer 12B. To do.

  Here, the thickness of the curable layer 12B is not particularly limited, but is prepared in the range of 1 μm to 50 μm, for example.

  Further, for example, if the thickness of the cured layer 12B is set such that the ink droplet 14A does not reach the lowermost layer of the cured layer 12B, the ink droplet 14A exists in the cured layer 12B after transfer to the recording medium P. The area where the area is not exposed and the ink droplet 14A does not exist functions as a protective layer after curing.

  Next, the ink droplets 14 </ b> A are ejected by the inkjet recording head 14, and the ink droplets 14 </ b> A are applied to the cured layer 12 </ b> B supplied on the intermediate transfer drum 10. The ink jet recording head 14 applies ink droplets 14A to predetermined positions of the cured layer 12B based on predetermined image information.

  At this time, the ink droplets 14 </ b> A are ejected by the inkjet recording head 14 on the intermediate transfer drum 10. That is, the ink droplets 14A are ejected to the cured layer 12B in a state where the drum surface is not bent.

  Next, the recording medium P is sandwiched between the intermediate transfer drum 10 by the transfer device 16 and pressure is applied to the cured layer 12B, so that the cured layer 12B on which the image is formed by the ink droplets 14A is formed on the recording medium P. Transcribed.

  Next, the irradiating device 18 cures the curable layer 12B, whereby the image T by the ink droplet 14A is fixed on the recording medium P by the curable resin. Thereby, a curable resin layer (image layer) including the image T by the ink droplet 14A is formed on the recording medium P.

  In the present embodiment, since the image recording composition described above is used, the cured layer formed on the recording medium P (the state after the cured layer 12B is cured) is applied to the recording medium P. The adhesion is 180 ° peel strength of 0.3 N / 25 mm or more, and the Shore D hardness (JIS K7215) is 80 degrees or less, and the adhesiveness to the recording medium P is maintained and the cured layer can be used. It is thought that flexibility will be realized.

  After the cured layer 12B is transferred to the recording medium P, the residue and foreign matter on the cured layer 12B remaining on the surface of the intermediate transfer drum 10 are removed by the cleaning device 20, and the solution is supplied onto the intermediate transfer drum 10 again. The image recording composition 12A is supplied from the apparatus 12 to form the cured layer 12B, and the image recording process is repeated.

  As described above, the recording apparatus 101 according to the present embodiment performs image recording.

  FIG. 2 is a configuration diagram illustrating a recording apparatus according to the second embodiment.

  As shown in FIG. 2, the recording apparatus 102 according to the second embodiment has a configuration in which an intermediate transfer belt (intermediate transfer member) 22 is disposed instead of the intermediate transfer drum 10 in the first embodiment.

  For example, the intermediate transfer belt 22 is rotatably supported by two support rolls 22A and a pressure roll 16B (transfer device 16) while applying tension from the inner peripheral surface side.

The intermediate transfer belt 22 has a width (length in the axial direction) equal to or greater than the width of the recording medium P.
The intermediate transfer belt 22 includes, for example, various resins [for example, polyimide, polyamideimide, polyester, polyurethane, polyamide, polyethersulfone, fluorine resin, and the like] and various rubbers (for example, nitrile rubber, ethylene propylene rubber, chloroprene). Rubber, isoprene rubber, styrene rubber, butadiene rubber, butyl rubber, chlorosulfonated polyethylene, urethane rubber, epichlorohydrin rubber, acrylic rubber, silicone rubber, fluorine rubber, etc.). The intermediate transfer belt 22 may be made of a metal material such as stainless steel. The intermediate transfer belt 22 may have a single layer configuration or a stacked configuration. Further, the intermediate transfer belt 22 may have a surface layer made of a releasable material such as a fluororesin or silicone rubber.

  Each recording head 14 has a non-bending region in the intermediate transfer belt that is rotationally supported under tension, and the distance between the surface of the intermediate transfer belt 22 and the nozzle surface of the head is, for example, about 0.7 mm to 1.5 mm. Are arranged.

  The transfer device 16 includes a pair of pressure rolls 16A and 16B arranged to face each other with the intermediate transfer belt 22 interposed therebetween.

  In the recording apparatus 102 according to the present embodiment, ink droplets 14 </ b> A are ejected by the inkjet recording head 14, and the ink droplets 14 </ b> A are applied to the cured layer 12 </ b> B formed on the intermediate transfer belt 22.

  At this time, the ejection of the ink droplets 14A by the ink jet recording head 14 is performed on a non-bent region in the intermediate transfer belt 22 that is rotated and supported by tension. That is, the ink droplets 14A are ejected to the cured layer 12B with the belt surface not deflected.

  Except for these, the aspects described in the first embodiment are applied, and thus the description thereof is omitted.

  FIG. 3 is a configuration diagram illustrating a recording apparatus according to the third embodiment.

  As shown in FIG. 3, the recording apparatus 103 according to the third embodiment is configured so that, in the first embodiment, before the layer to be cured 12 </ b> B formed with the ink droplets 14 </ b> A is transferred to the recording medium P, A second stimulus supply device 24 for supplying a stimulus for semi-curing the layer 12B is further arranged.

  For example, the second stimulus supply device 24 is disposed downstream of the inkjet recording head 14 in the rotation direction of the intermediate transfer drum 10 and upstream of the transfer device 16.

  The second stimulus supply device 24 applies, as the irradiation device 18, an ultraviolet irradiation device that irradiates the image recording composition 12 </ b> A (the cured layer 12 </ b> B formed thereby) with ultraviolet rays.

  The ultraviolet irradiation condition in the second stimulus supply device 24 is such that the layer to be cured 12B on the intermediate transfer drum 10 to which the ink droplets 14A are applied by the ink jet recording head 14 is semi-cured and applied to the recording medium P by the transfer device 16. There is no particular limitation as long as it is a transfer condition, and it can be selected according to the curable resin precursor species, the thickness of the layer to be cured, and the like.

  In the present embodiment, the second stimulus supply device 24 is arranged on the downstream side of the ink jet recording head 14 and the upstream side of the transfer device 16, but the second stimulus supply device 24 is arranged on the ink jet recording head. You may arrange | position upstream from 14.

  Here, the “semi-cured state” means that the image recording composition has not reached the “cured state”, but is hardened and not in a completely liquid state when supplied to the intermediate transfer member. State. One method for confirming the “semi-cured state” is as follows. Specifically, when permeable paper (for example, plain paper) is superimposed on the cured layer 12B, the cured layer 12B is not transferred to the paper side at all when no load is applied, and when a 200 g load is applied. When a part of the image is transferred, it is determined as a “half-cured state”.

  In the recording apparatus 103 according to the present embodiment described above, the ink droplets 14A are ejected by the ink jet recording head 14, and the ink droplets 14A are applied to the cured layer 12B supplied onto the intermediate transfer drum 10, and then the second. The stimulus supply device 24 semi-cures the layer 12B to be cured. Then, the cured layer 12B is transferred to the recording medium P by the transfer device 16. During this transfer, the cured layer 12B is transferred to the recording medium P in a semi-cured state, that is, in a state having some rigidity.

  Except for these, the aspects described in the first embodiment are applied, and thus the description thereof is omitted.

  FIG. 4 is a configuration diagram illustrating a recording apparatus according to the fourth embodiment.

  As shown in FIG. 4, the recording apparatus 104 according to the fourth embodiment has a form (direct recording method) in which an image is directly formed on a recording medium P.

  The recording apparatus 104 supplies an image recording composition 12A containing, for example, an anionic liquid-absorbing material and a curable resin precursor that is cured by an external stimulus (energy) onto the recording medium P to record an image. Solution supply device 12 for forming cured layer 12B formed of composition 12A, inkjet recording head 14 for ejecting ink droplets 14A on cured layer 12B to form image T, and cured layer 12B And an irradiating device 18 that supplies the stimulation to be performed.

  The recording apparatus 104 includes a conveyance belt 13 that conveys the recording medium P. As the transport belt 13, for example, an endless belt described as the intermediate transfer belt 22 in the second embodiment is used. For example, the transport belt 13 is rotatably supported by three support rolls 13A while applying tension from the inner peripheral surface side. The conveyor belt 13 conveys the recording medium P sent from a storage container (not shown) or the like in the direction of the arrow by rotating.

  In the recording device 104, first, the solution supply device 12 supplies the image recording composition 12 </ b> A onto the surface of the recording medium P being conveyed by the conveyance belt 13 to form the cured layer 12 </ b> B. Next, based on predetermined image information, the ink droplets 14A are ejected by the ink jet recording head 14, and the image T is formed by applying the ink droplets 14A to the cured layer 12B formed on the recording medium P. Finally, the cured layer 12B is cured by the irradiation device 18, whereby a cured layer including the image T by the ink droplets 14A is formed on the recording medium P.

  Except for these, the aspects described in the first embodiment are applied, and thus the description thereof is omitted.

  In the recording apparatus according to any of the embodiments described above, the image recording composition 12A is applied to the intermediate transfer drum 10, the intermediate transfer belt 22, or the recording medium P to form the cured layer 12B. Then, after applying the ink droplets 14A to the cured layer 12B to form the image T (in the first to third embodiments, after being further transferred to the recording medium P), the image T was formed. The cured layer 12B is completely cured by irradiation with ultraviolet rays. At this time, the cured layer 12B is cured to become a cured layer. Therefore, regardless of whether the recording medium P is a non-penetrable medium or a permeable medium, image formation is performed on various recording media P.

  In this embodiment, since the image recording composition described above is used as the image recording composition 12A, the adhesiveness of the cured layer formed on the recording medium P to the recording medium P is determined. It is considered that the flexibility of the cured layer can be improved while maintaining the above.

  Hereinafter, an example is given and it demonstrates more concretely. However, it is not particularly limited by these examples. In the following, “part” is based on mass unless otherwise specified.

[Example 1]
-Preparation of image recording composition-
First, a mixture of the following materials was prepared.
・ Silicone-modified urethane prepolymer (trade name: CN990, manufactured by Osaka Organic Chemicals)
.... 5% by mass
・ Urethane prepolymer (trade name: M1600, manufactured by Toa Gosei Co., Ltd.) 10% by mass
・ 2-hydroxyethyl methacrylate (trade name: HEMA, manufactured by Toagosei Co., Ltd., sp value = 11) (hydrophilic monomer): 10% by mass
・ TMP-0EOTAc (manufactured by Shin-Nakamura Chemical) ... 40% by mass

  Next, after adding 30% by weight of a mixture of aquaric CS7s (Nippon Catalyst) cross-linked sulfonic acid-modified sodium polyacrylate, which has been ball milled to a central particle size of 2.8 μm, and sized as liquid-absorbing resin particles, The mixture was mixed for 48 hours by ball mill stirring. Further, 5% by mass of IC184 (Ciba Specialty Chemicals) was added as a polymerization initiator to prepare an image recording composition A1.

―Preparation of ink―
・ Carbon black 5 parts ・ Styrene-acrylic acid-butyl acrylate ester 1.5 parts ・ Glycerin 25 parts ・ Diethylene glycol monobutyl ether 6 parts ・ Oxyethylene oleyl ether 0.5 parts And NaOH were added, followed by filtration through a 2 μm filter to obtain a black ink.

―Preparation of intermediate transfer member―
A perfluoroalkyl vinyl ether copolymer (manufactured by Asahi Glass Co., Ltd., Obligard) is applied to a polyimide seamless belt of 83 μm thickness (transparent belt using JSR transparent polyimide by flow coating) using a die coater (thickness 33 μm). And an intermediate transfer member.

  The intermediate transfer member is mounted as an intermediate transfer drum 10 on a recording apparatus having the structure shown in FIG. 1, and the image recording composition A1 prepared above is continuously applied to the intermediate transfer member with a thickness of 23 μm. A cured layer was formed. Then, a 100% solid and 2 dot-thick line image is printed on the cured layer with the black ink (resolution: 1200 × 1200 dpi, drop size: 2 pL), and then a recording medium (OK Kanto) with a weight of 1 kG. Transfer to top coat paper). Then, the cured layer on which the image was printed on the recording medium was irradiated with ultraviolet rays (160 seconds with a halogen lamp for 5 seconds) to cure the cured layer to obtain a cured layer.

<Evaluation>
The following measurements and evaluations were performed.

(Hardened layer thickness)
The thickness of the cured layer formed on the recording medium was measured. The measurement results are shown in Table 1.

(Shore D hardness of hardened layer)
The Shore D hardness of the cured layer formed on the recording medium was measured. The measurement results are shown in Table 1.
In addition, Shore D hardness of the hardened layer was performed according to the method described in JISK7215, and was performed using Shimadzu Dynamics micro hardness tester DUH-201S.

(water resistant)
After dropping one drop of water on the cured layer formed on the recording medium and wiping it with a waste cloth 60 seconds later, the state of residue on the dropping surface, such as dents and the form of wet marks, was evaluated based on the following table. The evaluation results are shown in Table 1.
G1: When there is almost no dent or dripping trace.
-G2: When the dent and the trace of dripping are visually observed.
G3: When dents and dripping marks are noticeable.

(Cross cut test)
The cured layer formed on the recording medium is subjected to a cross-cut test in accordance with JIS K5400, peeled off from the recording medium with cello tape (registered trademark), and transferred on the peeling tape remaining on the recording medium without peeling. Counted the number. The results are shown in Table 1.
The results of the cross cut test indicate that the smaller the “remaining number” value shown in Table 1, the higher the adhesion (adhesion) of the cured layer to the recording medium.

(Adhesive strength)
The cured layer formed on the recording medium was subjected to a peeling test according to JIS K6301 in an environment of 22 ° C. and 55% RH, and the peeling strength from the recording medium was measured. In addition, the size of the strip-shaped test piece used in this peeling test was 25 mm in width and 90 mm in length. The tensile speed was 10 mm / min. The measurement results are shown in Table 1.

(Bending test)
The cured layer formed on the recording medium was bent at 180 ° to make a crease, and evaluated according to the following evaluation criteria.
G1: When there is no crease and there is recoverability after deformation.
G2: When the crease remains but there is no crack and the deformation remains.
G3: When cracks and deformation traces remain in the hardened layer along the crease.

(Transfer efficiency)
The transfer efficiency (%) of the cured layer to the recording medium was measured by the following method.
The mass of the intermediate transfer belt per unit area (10 × 10 cm) is measured in advance, and is obtained from the mass of the coating film when the curable solution is applied thereon, and the mass of the intermediate transfer belt after being transferred to a sheet and cured. It was. The measurement results are shown in Table 1.

(Evaluation of uneven printing in the image area)
The density was measured using X-Rite 968 (manufactured by X-Rite), and the degree of occurrence of printing unevenness of the formed image was evaluated according to the following criteria.
G1: When density measurement is performed at any 10 locations (parts with different droplet ejection densities) in the image area, and the difference between the maximum density and the minimum density is 0.05 or less.
G2: When density measurement is performed at any 10 locations (parts with different droplet ejection densities) in the image area, and the difference between the maximum density and the minimum density is 0.1 or less.
G3: When density measurement is performed at any 10 locations (parts with different droplet ejection densities) in the image area, and the difference between the maximum density and the minimum density exceeds 0.1.

(Evaluation of uneven density in image area)
The density unevenness of the image on the cured layer formed on the recording medium was visually confirmed. The evaluation criteria are as follows. The evaluation results are shown in Table 1.

G1: No density unevenness is observed in the highlight image.
G2: A slight unevenness in the density of the highlight image is observed, but there is no practical problem.
G3: Density unevenness of the highlight image is observed in some places, but at a level where there is no practical problem.
G4: A level in which the density unevenness of the highlight image is noticeable and becomes a problem in practical use.

[Example 2]
The silicone-modified urethane prepolymer (trade name: CN990, manufactured by Osaka Organic Chemical Co., Ltd., weight average molecular weight 20000) in the image recording composition A1 prepared in Example 1 was converted into a dimethylsilicone-modified urethane prepolymer (trade name: UV3500, Big Chemie A hardened layer was formed on the recording medium under the same production method and under the same conditions as in Example 1 except that the image recording composition A2 was prepared instead of (manufactured by Japan ), and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 3
The silicone-modified urethane prepolymer (trade name: CN990, manufactured by Osaka Organic Chemical Co., Ltd.) in the image recording composition A1 prepared in Example 1 was changed to a silicone-modified urethane prepolymer (trade name: UV3700, manufactured by Nippon Synthetic Chemical Industry Co., Ltd. ). Instead, instead of 2-hydroxyethyl methacrylate (trade name: HEMA, manufactured by Toagosei Co., Ltd., sp value = 11) used as the hydrophilic monomer in Example 1, phenoxyacrylate (manufactured by Toagosei Co., Ltd., sp value) was used as the hydrophilic monomer. A cured layer was formed on a recording medium under the same production method and under the same conditions as in Example 1 except that the image recording composition A3 using = 9.7) was prepared, and the same test as in Example 1 was performed. . The evaluation results are shown in Table 1.

Example 4
In the image recording composition A2 prepared in Example 2, N was used as the hydrophilic monomer in place of the 2-hydroxyethyl methacrylate (trade name: HEMA, manufactured by Toagosei Co., Ltd., sp value = 11) used as the hydrophilic monomer. , N-dihydroxyethylacrylamide (manufactured by Kojin Co., Ltd., trade name: HEA) was used except that a composition A4 for image recording was prepared, and a cured layer was formed on the recording medium under the same production method and conditions as in Example 2. The same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 5
Image recording composition A5 which does not contain 2 hydroxyethyl methacrylate (trade name: HEMA, manufactured by Toagosei Co., Ltd., sp value = 11) used as a hydrophilic monomer in image recording composition A1 prepared in Example 1. A hardened layer was formed on the recording medium under the same production method and the same conditions as in Example 1 except that was prepared, and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 6
In the image recording composition A1 prepared in Example 1, the amount of the silicone-modified urethane prepolymer was 5% by mass in Example 1, except that the image recording composition A6 was adjusted to 30% by mass. A cured layer was formed on the recording medium under the same manufacturing method and the same conditions as in Example 1, and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 7
In the image recording composition A1 prepared in Example 1, the amount of the silicone-modified urethane prepolymer was 5% by mass in Example 1, except that the image recording composition A7 was adjusted to 20% by mass. A cured layer was formed on the recording medium under the same manufacturing method and the same conditions as in Example 1, and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 8
In the image recording composition A1 prepared in Example 1, the amount of the silicone-modified urethane prepolymer was 5% by mass in Example 1, except that the image recording composition A8 was adjusted to 32% by mass. A cured layer was formed on the recording medium under the same manufacturing method and the same conditions as in Example 1, and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

Example 9
Example 1 except that the image-recording composition A9 was prepared by further adding 5% by mass of a reactive silicone-modified polyol (by Big Chemie Japan , UV3570) to the image-recording composition A1 prepared in Example 1. A cured layer was formed on the recording medium under the same production method and under the same conditions as in Example 1, and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

[Comparative Example 1]
On the recording medium with the same production method and the same conditions as in Example 1 except that the image recording composition A1 prepared in Example 1 was adjusted to contain an image recording composition B1 having no silicone-modified urethane prepolymer. A hardened layer was formed and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

[Comparative Example 2]
Instead of 5% by mass of the silicone-modified urethane prepolymer (trade name: CN990, manufactured by Osaka Organic Chemical Co., Ltd.) used in the image recording composition A1 prepared in Example 1, a silicone-modified urethane having no ultraviolet curable group Except for adjusting the image recording composition B2 using 5% by mass of non-reacting KF615A (manufactured by Shin-Etsu Silicone, HLB = 10) as a prepolymer, curing was performed on the recording medium under the same manufacturing method and the same conditions as in Example 1. A layer was formed and the same test as in Example 1 was performed. The evaluation results are shown in Table 1.

  As shown in Table 1, the flexibility of the cured layer was improved in the examples as compared with the comparative examples. In addition, compared with the comparative example, the adhesiveness of the cured layer to the recording medium was also improved in the examples.

DESCRIPTION OF SYMBOLS 10 Intermediate transfer drum (intermediate transfer body), 12 Solution supply apparatus, 12A Image recording composition, 12B Curing layer, 14 Inkjet recording head, 16 Transfer apparatus, 16A Pressure roll, 16B Pressure roll, 18 Irradiation apparatus, 22 intermediate transfer belt (intermediate transfer member), 24 second irradiation device, 101 recording device, 102 recording device, 103 recording device, 104 recording device

Claims (9)

An absorbent component;
A silicone-modified urethane prepolymer having an ultraviolet curable group;
An image recording composition for forming a cured layer in which droplets containing an aqueous solvent are discharged . The image recording composition according to claim 1, wherein the liquid absorbing component comprises a liquid absorbing resin. The image recording composition according to claim 1, further comprising a hydrophilic monomer having a solubility parameter of 9.7 or more. The silicone-modified urethane prepolymer image recording composition according content to any one of claims 1 to 3 in the range of 30 mass% 1 mass% or more of. Image recording composition according to any one of the reactive silicone-modified polyols further contain claims 1 to 4. The image recording composition according to any one of claims 1 to 5 , wherein the silicone-modified urethane prepolymer has a weight average molecular weight of 1,000 to 30,000. The image recording composition according to any one of claims 1 to 6 , wherein the silicone-modified urethane prepolymer is a silicone-modified polyester urethane prepolymer or a silicone-modified polyether urethane prepolymer. An intermediate transfer member;
A supply device that supplies the image recording composition according to any one of claims 1 to 7 to the intermediate transfer member;
A discharge device that discharges droplets containing an aqueous solvent onto a cured layer formed by the image recording composition supplied on the intermediate transfer member;
A transfer device for transferring the cured layer to which the droplets have been discharged from the intermediate transfer member to a recording medium;
An irradiation device for irradiating the cured layer with ultraviolet rays;
Recording device. A supply device for supplying the image recording composition according to any one of claims 1 to 7 to a recording medium;
An ejection device for ejecting liquid droplets containing an aqueous solvent onto a cured layer formed of the image recording composition supplied on the recording medium;
An irradiation device for irradiating the cured layer on which the droplets are discharged with ultraviolet rays;
Recording device.

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