JP6552199B2 - Image recording method, ink and liquid composition - Google Patents

Description

  The present invention relates to an image recording method, and an ink and a liquid composition used for the image recording method.

  2. Description of the Related Art Conventionally, in an image recording method, there is a two-liquid reaction type image recording method (two-liquid reaction system) using an ink containing a pigment (pigment ink) and a liquid composition that destabilizes the dispersion state of the pigment in the ink. It is being considered.

  Patent Document 1 discloses an image recording method using an ink containing a pigment and a resin particle having a structure derived from a methacrylic acid derivative, and a liquid composition containing an organic acid. Is described to be suppressed.

JP, 2010-31267, A

  However, according to the study by the present inventors, the image recording method described in Patent Document 1 cannot obtain an image with a high level of image quality when performing high-speed recording as required in recent years.

  Accordingly, an object of the present invention is to provide an image recording method capable of obtaining an image with high image quality when high speed recording is performed.

The above object is achieved by the present invention described below. That is, the image recording method according to the first embodiment of the present invention includes a step of applying an ink containing a pigment and anionic resin particles to a recording medium, and a dispersion of the pigment or the anionic resin particles in the ink. Applying the liquid composition that destabilizes the state to the recording medium so as to at least partially overlap the region to which the ink is applied, and based on the total mass of the ink, the anionic resin The content of the particles is 1% by mass or more, and the ink further contains a compound represented by the following general formula (1).

An image recording method according to the second embodiment of the present invention includes a step of applying an ink containing a pigment and anionic resin particles to a recording medium, and a dispersion of the pigment or the anionic resin particles in the ink. Applying the liquid composition that destabilizes the state to the recording medium so as to at least partially overlap the region to which the ink is applied, and based on the total mass of the ink, the anionic resin Content of particle | grains is 1 mass% or more, The said liquid composition contains the compound represented by following General formula (1), It is characterized by the above-mentioned.

In addition, the image recording method according to the third embodiment of the present invention includes a step of applying a clear ink containing anionic resin particles to a recording medium, and a dispersion state of the anionic resin particles in the clear ink. Applying the liquid composition to be stabilized to the recording medium so as to at least partially overlap the region to which the clear ink is applied, and based on the total mass of the clear ink, the anionic resin particles The clear ink further contains a compound represented by the following general formula (1).

(In General Formula (1), R represents an alkyleneoxy group, n and p are each independently an integer of 9 to 20, m and q are each independently an integer of 1 or more, and l is an integer of 4 to 250. .)

  According to the present invention, it is possible to provide an image recording method capable of obtaining an image with high image quality.

It is a schematic diagram which shows an example of a structure of the recording device used for this invention.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments.

  The inventors first examined the cause of the failure to obtain a high-level image when performing high-speed recording in the conventional image recording method using the two-component reaction system. The results are described below.

  A conventional image recording method using a two-component reaction system is designed to increase the reactivity between ink (including clear ink) and a liquid composition in order to effectively suppress bleeding and bleeding. . Specifically, when the ink containing the pigment and the anionic resin particle (clear ink containing the anionic resin particle) comes in contact with the liquid composition, the pigment and the anionic resin particle quickly aggregate on the recording medium. As described above, ink (clear ink) and liquid composition are prepared. When high-speed recording is performed, the timing at which the ink (clear ink) is applied and the timing at which the liquid composition is applied are very close, and the ink and the liquid composition may be mixed in a liquid state. At this time, if the reactivity between the ink (clear ink) and the liquid composition is too high, volumetric shrinkage occurs when the pigment or resin particles are coagulated, and aggregates of the pigment or resin particles which are volumetrically shrunk are ink (clear It has been found that a phenomenon (image movement phenomenon) occurs in which the pigment is fixed in a region shifted from a desired region of the recording medium by moving in the region where the ink) and the liquid composition are applied.

  When the present inventors examined a method for suppressing this image movement phenomenon, the configuration of the present invention was reached. Specifically, the ink containing the pigment and the anionic resin particles (first embodiment), the clear ink containing the anionic resin particles (third embodiment), or the ink (clear ink) is used. One of the liquid compositions (second embodiment) contains a compound represented by the following general formula (1).

(In General Formula (1), R represents an alkyleneoxy group, n and p are each independently an integer of 9 to 20, m and q are each independently an integer of 1 or more, and l is an integer of 4 to 250. .)

The mechanism by which the effect of the present invention can be obtained by this configuration will be described below.
The compound represented by the general formula (1) is a so-called “polyoxyalkylene fatty acid diester”, which has hydrophobic groups at both ends and has a polyoxyalkylene structure at the center. Therefore, it can form a hydrophobic interaction and a hydrogen bond with the pigment or anionic resin particles in the ink. Therefore, when the ink and the liquid composition are mixed, the pigment and the anionic resin particles cause an aggregation reaction in a state where the compound represented by the general formula (1) is adsorbed. At this time, the aggregation reaction itself occurs quickly, but the aggregate is present in a state in which the compound represented by the general formula (1) is taken in between the pigment and the resin particles, so that volume shrinkage due to the aggregation reaction is unlikely to occur. . Thus, it is considered that the image transfer phenomenon is suppressed while enhancing high-speed cohesion.

  As in the above mechanism, the effects of the present invention can be achieved by the synergistic effects of the components.

<Compound Represented by General Formula (1)>
In the general formula (1), R represents an alkyleneoxy group. As the alkyleneoxy group, a methyleneoxy group, an ethyleneoxy group, and a propyleneoxy group are preferable. R may be a combination of a plurality of alkyleneoxy groups. For example, it includes a case where both ethyleneoxy group and propyleneoxy group are included and the total number of repetitions of each is 1. The alkyleneoxy group can be branched by a compound having a plurality of hydroxyl groups, and those obtained by adding ethylene oxide or propylene oxide to hydroxyl groups such as glycerin, polyglycerin, sugar and polyhydric alcohol may be used.

  In the general formula (1), l is the repeating number of the alkyleneoxy group and represents an integer of 4 to 250. Furthermore, the integer of 9 to 100 is preferable. When l is smaller than 4, sufficient solubility can not be obtained. On the other hand, if l is larger than 250, the viscosity of the liquid containing the compound represented by the general formula (1) tends to increase.

In the general formula (1), n and p are each independently an integer of 9 to 20, and m and q are each independently an integer of 1 or more. n and p are values relating to the hydrophobicity of the compound represented by the general formula (1), derived from the number of carbon atoms of the fatty acid forming the ester bond. When n and p are smaller than 9, hydrophobic interaction with the pigment and resin particles is weakened, and the above-mentioned image transfer suppressing effect can not be sufficiently obtained. When n and p are larger than 20, the hydrophobicity is too high, and thus the viscosity of the liquid containing the compound represented by the general formula (1) is likely to increase. As a fatty acid for obtaining the compound represented by General formula (1), it is preferable to use a C9-C20 fatty acid. Specific examples include lauric acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, isopalmitic acid, isostearic acid, isooleic acid and the like. Note that m and q correspond to the number of hydrogen atoms, and may vary depending on the type of carbon-carbon bond of the fatty acid carbon chain (for example, m = 2n + 1 when C _n H _m is an alkyl group).

  Examples of commercially available compounds represented by the general formula (1) include Ionette DL-200, DS300, DS400, DS4000, DO-400, DO600, DO1000 (manufactured by Sanyo Chemical Industries), Nonion DL-40HN, DP1.5HN, DO-4HN, DO4-40HN, DS40-HN, DS-110HN, DIS-400, DIS-600 (manufactured by NOF Corporation) and the like can be mentioned.

(Regarding the content of the compound represented by the general formula (1))
(1) First Embodiment In the first embodiment, the compound represented by the general formula (1) is used in an ink containing a pigment and anionic resin particles.

  In the first embodiment, the content of the compound represented by the general formula (1) based on the total mass of the ink is preferably 0.2% by mass or more, and 0.5% by mass or more and 10. It is more preferable that it is 0 mass% or less.

  In the first embodiment, the content of the anionic resin particles based on the total mass of the ink is 0.5 times or more by mass ratio with respect to the content of the compound represented by the general formula (1) 20 0.0 times or less is preferable, and 0.5 times or more and 5.0 times or less is more preferable. When the mass ratio is smaller than 0.5 times, the amount of the compound represented by the general formula (1) is relatively large with respect to the resin particles, and aggregation can be inhibited. It may not be obtained. When the mass ratio is larger than 20.0 times, the amount of the compound represented by the general formula (1) with respect to the resin particles is relatively small, and the above-described image movement suppression effect may not be sufficiently obtained. is there.

(2) Second Embodiment In the second embodiment, the compound represented by the general formula (1) is used in a liquid composition that destabilizes the dispersion state of pigments or anionic resin particles in ink. Be

  In 2nd Embodiment, it is preferable that content of the compound represented by General formula (1) on the basis of the total mass of a liquid composition is 5.0 mass% or more, and 6.0 mass% or more It is more preferable that it is, and it is especially preferable that it is 20.0 mass% or more and 70.0 mass% or less.

  In the second embodiment, the application amount of the anionic resin particles derived from the ink to the recording medium is in a mass ratio with respect to the application amount of the compound represented by the general formula (1) derived from the liquid composition. It is preferably 0.3 times or more and 60.0 times or less, and more preferably 0.5 times or more and 40.0 times or less. If the mass ratio is smaller than 0.3 times, the amount of the compound represented by the general formula (1) is relatively large with respect to the resin particles, and aggregation can be inhibited. It may not be obtained. When the mass ratio is larger than 60.0 times, the amount of the compound represented by the general formula (1) with respect to the resin particles is relatively small, and the above-described image movement suppression effect may not be sufficiently obtained. is there.

(3) Third Embodiment In the third embodiment, the compound represented by the general formula (1) is used in a clear ink containing anionic resin particles.

  In 3rd Embodiment, it is preferable that content of the compound represented by General formula (1) on the basis of the clear ink total mass is 0.2 mass% or more, and 0.5 mass% or more 10 It is more preferable that it is not more than 0% by mass.

  In the third embodiment, the content of the anionic resin particles based on the total mass of the clear ink is 0.5 times or more in mass ratio with respect to the content of the compound represented by the general formula (1). It is preferably 20.0 times or less, and more preferably 0.5 times or more and 5.0 times or less. When the mass ratio is smaller than 0.5 times, the amount of the compound represented by the general formula (1) is relatively large with respect to the resin particles, and aggregation can be inhibited. It may not be obtained. When the mass ratio is larger than 20.0 times, the amount of the compound represented by the general formula (1) with respect to the resin particles is relatively small, and the above-described image movement suppression effect may not be sufficiently obtained. is there.

<Ink>
In the present invention, the ink contains a pigment and anionic resin particles. Furthermore, it may contain an aqueous medium and other components. Hereinafter, materials that can be used for the ink will be described. In the following description, “(meth) acrylic acid” and “(meth) acrylate” represent “acrylic acid, methacrylic acid” and “acrylate, methacrylate”, respectively.

(Pigment)
In the present invention, the pigment content in the ink is preferably 0.5% by mass or more and 15.0% by mass or less, more preferably 1.0% by mass or more and 10.0% by mass or less, based on the total mass of the ink. Is more preferable.

  As a method for dispersing the pigment, a resin dispersion type pigment using a resin as a dispersant (a resin dispersed pigment using a resin dispersant, a microcapsule pigment in which the surface of pigment particles is coated with a resin, and a resin on the surface of pigment particles) Resin-bonded pigments in which organic groups are chemically bonded) and self-dispersion type pigments (self-dispersing pigments) in which hydrophilic groups are introduced on the surface of pigment particles. Of course, it is also possible to use pigments having different dispersion methods in combination. As a specific pigment, carbon black or an organic pigment is preferably used. Moreover, a pigment can be used combining 1 type or 2 types or more. When the pigment used in the ink is the resin dispersion type pigment, a resin is used as a dispersant. It is preferable that the resin used as the dispersant has both a hydrophilic site and a hydrophobic site. Specifically, an acrylic resin polymerized using a monomer having a carboxyl group such as acrylic acid or methacrylic acid; a urethane resin polymerized using a diol having an anionic group such as dimethylol propionic acid, and the like can be mentioned. Moreover, it is preferable that the acid value of resin used as a dispersing agent is 50 mgKOH / g or more and 550 mgKOH / g or less. Moreover, it is preferable that the polystyrene equivalent weight average molecular weight (Mw) obtained by GPC of resin used as a dispersing agent is 1,000 or more and 50,000 or less. Further, the content of the resin dispersant in the ink is 0.1% by mass or more and 10.0% by mass or less, and further 0.2% by mass or more and 4.0% by mass or less based on the total mass of the ink. Is preferred. Moreover, it is preferable that content of a resin dispersing agent is 0.1 times or more and 3.0 times or less by mass ratio with respect to content of a pigment.

(Anionic resin particles)
In the present invention, the “resin particle” means a resin that is dispersed in a solvent and has a particle size. In the present invention, the 50% cumulative volume average particle size (D ₅₀ ) of the resin particles is preferably 10 nm or more and 1,000 nm or less. More preferably, it is 50 nm or more and 500 nm or less. In the present invention, the D ₅₀ of the resin particles is measured by the following method. The resin particle dispersion was diluted 50 times (volume basis) with pure water, and using UPA-EX150 (manufactured by Nikkiso), SetZero: 30 s, number of measurements: 3 times, measurement time: 180 seconds, refractive index: 1 Measured under the measurement conditions of .5.

  Moreover, it is preferable that the weight average molecular weight of polystyrene conversion obtained by the gel permeation chromatography (GPC) of a resin particle is 1,000 or more and 2,000,000 or less.

  Furthermore, it is preferable that the minimum film-forming temperature of a resin particle is 20 to 100 degree. In addition, the measuring method of the minimum film-forming temperature of the resin particle in this invention is based on "how to obtain | require the minimum film-forming temperature" of JISK6828-2.

  In the image recording method of the present invention, the content (% by mass) of the resin particles in the ink is preferably 1% by mass or more based on the total mass of the ink. Furthermore, it is preferable that it is 3 mass% or more, and it is more preferable that they are 5 mass% or more and 15 mass% or less.

  In the present invention, any resin particles can be used for the ink as long as they satisfy the above-mentioned definition of the resin particles. As the monomer used for the resin particles, any monomer that can be polymerized by an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, or the like can be used. Depending on the difference in monomers, for example, resin particles of acrylic type, vinyl acetate type, ester type, ethylene type, urethane type, synthetic rubber type, vinyl chloride type, vinylidene chloride type, olefin type, etc. can be mentioned, among which acrylic resin It is preferable to use particles and urethane resin particles.

  Monomers specifically usable for the acrylic resin particles include (meth) acrylic acid, maleic acid, crotonic acid, angelic acid, itaconic acid, fumaric acid and other α, β-unsaturated carboxylic acids and salts thereof; Meta) acrylate, methyl (meth) acrylate, butyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, diethylene glycol (meth) acrylate, triethylene glycol (meth) acrylate, tetraethylene glycol (meth) Acrylate, polyethylene glycol (meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxytetraethylene glycol (meth) acrylate, methoxy Ci-polyethylene glycol (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, monobutyl maleate, α, β-unsaturated carboxylic acids such as dimethyl itaconate (Meth) acrylamide, dimethyl (meth) acrylamide, N, N-dimethylethyl (meth) acrylamide, N, N-dimethylpropyl (meth) acrylamide, isopropyl (meth) acrylamide, diethyl (meth) acrylamide, (meth ) Alkylamide compounds of α, β-unsaturated carboxylic acids such as acryloylmorpholine, maleic acid monoamide, and crotonic acid methylamide; styrene, α-methylstyrene, phenyl vinyl acetate, benzyl (meth) Α, β-ethylenically unsaturated compounds having an aryl group such as acrylate and 2-phenoxyethyl (meth) acrylate; and ester compounds of polyfunctional alcohols such as ethylene glycol diacrylate and polypropylene glycol dimethacrylate. These may be a homopolymer obtained by polymerizing a single monomer or a copolymer obtained by polymerizing two or more monomers. When the resin particles are a copolymer, it may be a random copolymer or a block copolymer. Among them, resin particles using a hydrophilic monomer and a hydrophobic monomer are preferable. Examples of hydrophilic monomers include α, β-unsaturated carboxylic acids and salts thereof, and examples of hydrophobic monomers include α, β-unsaturated carboxylic acid ester compounds and α, β-ethylenically unsaturated groups having an aryl group. Compounds are mentioned.

  Urethane resin particles are resin particles synthesized by reacting a polyisocyanate, which is a compound having two or more isocyanate groups, with a polyol compound, which is a compound having two or more hydroxyl groups. In the present invention, any urethane resin particles obtained by reacting a known polyisocyanate compound with a known polyol compound can be used as long as the above resin particle conditions are satisfied.

  On the other hand, examples of the resin particle structure include resin particles having a single layer structure and resin particles having a multilayer structure such as a core-shell structure. In the present invention, it is preferable to use resin particles having a multilayer structure. In particular, it is more preferable to use a resin particle having a core-shell structure. Since the resin particles have a core-shell structure, the core portion and the shell portion are clearly functionally separated. The resin particles having such a core-shell structure have an advantage that more functions can be imparted to the ink as compared with resin particles having a single layer structure.

(Aqueous medium)
The ink of the present invention can use water or an aqueous medium which is a mixed solvent of water and a water-soluble organic solvent. The content of the water-soluble organic solvent is preferably 3.0% by mass or more and 50.0% by mass or less based on the total mass of the ink. As the water-soluble organic solvent, any conventionally used one can be used. Examples thereof include alcohols, glycols, alkylene glycols having 2 to 6 carbon atoms in the alkylene group, polyethylene glycols, nitrogen-containing compounds, and sulfur-containing compounds. These water-soluble organic solvents may be used alone or in combination of two or more as needed. The water is preferably deionized water (ion-exchanged water). The water content is preferably 50.0% by mass or more and 95.0% by mass or less based on the total mass of the ink.

(Other ingredients)
In addition to the above components, the ink of the present invention is a water-soluble organic compound that is solid at room temperature, such as polyhydric alcohols such as trimethylolpropane and trimethylolethane, and urea derivatives such as urea and ethyleneurea. It may contain. Furthermore, the ink and the liquid composition of the present invention are optionally provided with a surfactant, a pH adjuster, a rust inhibitor, a preservative, an antifungal agent, an antioxidant, an anti-reduction agent, an evaporation accelerator, and a chelation agent. You may contain various additives, such as an agent and resin.

<Liquid composition>
In the present invention, the liquid composition destabilizes the dispersion state of the pigment or the anionic resin particles in the ink. Specifically, it is preferable to contain a reactive agent that exhibits such an action. Furthermore, it may contain an aqueous medium and other components. Further, the application amount of the liquid composition is preferably 0.1 g / m ² or more and 10.0 g / m ² or less.

  In the present invention, the liquid composition is preferably colorless, milky white, or white so as not to affect the image recorded with the ink. Therefore, the ratio of the maximum absorbance to the minimum absorbance (maximum absorbance / minimum absorbance) in the wavelength range of 400 nm to 800 nm, which is the wavelength range of visible light, is preferably 1.0 or more and 2.0 or less. This means that in the wavelength range of visible light, there is substantially no absorbance peak, or even if it has, the intensity of the peak is extremely small. Furthermore, in the present invention, the liquid composition preferably does not contain a coloring material. The absorbance may be measured with a Hitachi double beam spectrophotometer U-2900 (manufactured by Hitachi High-Technologies) using an undiluted liquid composition. At this time, the absorbance may be measured by diluting the liquid composition. This is because the value of the ratio of the maximum absorbance to the minimum absorbance (maximum absorbance / minimum absorbance) does not depend on the dilution ratio since the maximum absorbance and the minimum absorbance of the liquid composition are both proportional to the dilution ratio.

  Hereinafter, materials that can be used for the liquid composition will be described.

(Reactant)
In the present invention, the liquid composition contains a reactive agent which causes the components of the ink (coloring material, resin, etc.) to precipitate and aggregate. As the reactant, a conventionally known compound can be used, and among them, at least one selected from polyvalent metal ions and organic acids is preferably used. It is also preferable to include a plurality of types of reactants in the liquid composition.

Specific 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 ^And trivalent metal ions such as ³⁺ . In the present invention, the polyvalent metal ion can be added to the liquid composition in the form of a salt such as hydroxide or chloride, and may be used as an ion generated by dissociation. In the present invention, the content of the polyvalent metal ion is preferably 3% by mass or more and 90% by mass or less based on the total mass of the liquid composition.

  In addition, specific examples of the organic acid include oxalic acid, polyacrylic acid, formic acid, acetic acid, propionic acid, glycolic acid, malonic acid, malic acid, maleic acid, ascorbic acid, levulinic acid, succinic acid, glutaric acid, glutamic acid, Examples include fumaric acid, citric acid, tartaric acid, lactic acid, pyrrolidone carboxylic acid, pyrone carboxylic acid, pyrrole carboxylic acid, furan carboxylic acid, pyridine carboxylic acid, coumaric acid, thiophene carboxylic acid, nicotinic acid, oxysuccinic acid, dioxysuccinic acid it can. In the present invention, the content of the organic acid is preferably 3% by mass or more and 99% by mass or less based on the total mass of the liquid composition.

(Aqueous medium)
The liquid composition of the present invention can use water or an aqueous medium that is a mixed solvent of water and a water-soluble organic solvent. The content of the water-soluble organic solvent is preferably 3.0% by mass or more and 50.0% by mass or less based on the total mass of the liquid composition. As the water-soluble organic solvent, any conventionally used one can be used. Examples thereof include alcohols, glycols, alkylene glycols having 2 to 6 carbon atoms in the alkylene group, polyethylene glycols, nitrogen-containing compounds, and sulfur-containing compounds. These water-soluble organic solvents may be used alone or in combination of two or more as needed. It is preferable to use deionized water (ion exchange water) as the water. The content of water is preferably 50.0% by mass or more and 95.0% by mass or less based on the total mass of the liquid composition.

(Other ingredients)
In addition to the above components, the liquid composition may contain a water-soluble organic compound that is solid at room temperature, such as polyhydric alcohols such as trimethylolpropane and trimethylolethane, and urea derivatives such as urea and ethyleneurea. You may contain. Furthermore, the ink and the liquid composition of the present invention are optionally provided with a surfactant, a pH adjuster, a rust inhibitor, a preservative, an antifungal agent, an antioxidant, an anti-reduction agent, an evaporation accelerator, and a chelation agent. You may contain various additives, such as an agent and resin.

  In particular, liquid compositions are resin particles such as acrylic resin particles, urethane resin particles, and polyolefin resin particles, from the viewpoint of imparting strength and slipperiness to the obtained image to improve scratch resistance; silica particles, titania particles, alumina particles, It is preferable to contain inorganic particles such as zirconia particles; silicone oil, fluorine oil and the like. The content of these materials is preferably 1% by mass or more and 30% by mass or less based on the total mass of the liquid composition.

[Image recording method]
In the present invention, an image is recorded using the ink or liquid composition described above. As the image recording method of the present invention, an ink and a liquid composition are directly applied to a recording medium, and an “direct drawing type image recording method” for recording an image; and an ink and a liquid composition are applied to an intermediate transfer member as a recording medium. There is an “intermediate transfer type image recording method” in which an intermediate image is formed by transferring the intermediate image onto a recording medium such as paper and then recording the image. The respective image recording methods will be described below.

[1] Direct-drawing type image recording method In the direct-drawing type image recording method, the ink application step (A) for applying ink to a recording medium and the liquid composition are recorded so as to overlap at least partly with the region to which ink is applied. And a liquid composition application step (B) to be applied to the medium. Furthermore, it may have a fixing step of pressing the recording medium on which the image is recorded by the above steps (A) and (B) with a roller.

  In the present invention, the step (B) may be performed after the step (A), or the step (A) may be performed after the step (B). Further, when the same process is performed twice or more, for example, the process (A) → the process (B) → the process (A) or the process (B) → the process (A) → the process (B) may be performed. In particular, it is more preferable to include the process of performing the step (A) after the step (B) because the effect of improving the image quality is large.

[Ink application process]
The means for applying ink to the recording medium is preferably an ink jet recording method having a step of recording on the recording medium by discharging ink from an ink jet recording head in accordance with a recording signal. In particular, an ink jet recording method in which thermal energy is applied to ink and ink is ejected from the ejection port of the recording head is preferable.

[Liquid composition application step]
Examples of means for applying the liquid composition to the recording medium include an inkjet method and a coating method. As a coating method, a roller coating method, a bar coating method, a spray coating method etc. are mentioned, for example.

[Fixing process]
In the fixing step, the smoothness of the image can be enhanced by applying pressure. At this time, when pressing the recording medium with a roller, it is preferable to heat the roller. By pressurizing with a heated roller, the fastness of the image can be enhanced, and further, the glossiness of the image obtained by adjusting the heating temperature can be controlled.

<Recording medium>
In the direct-drawing type image recording method, the recording medium includes not only paper used for general printing but also cloth, plastic, film, and the like. The recording medium used in the image recording method of the present invention may be previously cut into a desired size. Alternatively, a sheet wound in a roll shape may be used and cut into a desired size after image recording.

[2] Intermediate Transfer Type Image Recording Method In the intermediate transfer type image recording method, “intermediate transfer member” corresponds to “recording medium”. Therefore, a recording medium such as paper on which an intermediate image is finally transferred will be described as a "transfer medium".

  FIG. 1 is a schematic diagram showing an example of an intermediate transfer type image recording method. In FIG. 1, the intermediate transfer member 10 includes a rotatable drum-shaped support member 12 and a surface layer member 11 disposed on the outer peripheral surface of the support member 12. The intermediate transfer member 10 (support member 12) is driven to rotate in the direction of the arrow (counterclockwise in the figure) about the rotation shaft 13. In addition, in synchronization with the rotation of the intermediate transfer member 10, the components disposed around the intermediate transfer member 10 are configured to operate. The liquid composition is applied to the intermediate transfer body 10 by the application roller 14 or the like. The ink is applied from the ink jet recording head 15, and an intermediate image in which a desired image is mirror-reversed is formed on the intermediate transfer body 10. Next, the temperature adjustment mechanism 17 may adjust the temperature of the intermediate image formed on the intermediate transfer member to a desired temperature. At this time, the liquid in the intermediate image formed on the intermediate transfer member may be removed by the liquid removing mechanism 16. Next, the intermediate image is transferred to the transfer medium 18 by bringing the transfer medium 18 and the intermediate transfer body 10 into contact with each other using the pressure roller 19. A cleaning unit 20 may be provided as a step of cleaning the surface of the intermediate transfer member. Hereinafter, the intermediate transfer member and each step will be described.

<Intermediate transfer body>
The intermediate transfer member is a recording medium which holds a liquid composition and an ink and on which an intermediate image is recorded. Examples of the intermediate transfer member include a support member for handling itself to transmit a necessary force and a surface layer member on which an intermediate image is recorded. The support member and the surface layer member may be integrated.

  Examples of the shape of the intermediate transfer member include a sheet shape, a roller shape, a drum shape, a belt shape, and an endless web shape. In addition, the size of the intermediate transfer member can be appropriately set in accordance with the size of the recordable transfer medium.

  The support member of the intermediate transfer member is required to have a certain degree of strength from the viewpoint of conveyance accuracy and durability. As the material of the support member, metals, ceramics, resins, and the like are preferable. Among these, aluminum, iron, stainless steel, acetal resin, epoxy resin, polyimide, polyethylene, polyethylene terephthalate, nylon, polyurethane, silica ceramic, and alumina ceramic are preferable. When the support member is made of these materials, rigidity and dimensional accuracy that can withstand pressurization during transfer can be ensured, and inertia during operation can be reduced to improve control responsiveness. In addition, these materials can be used individually by 1 type or in combination of 2 or more types.

  The intermediate transfer member is required to have a certain degree of elasticity in the surface layer in order to transfer the intermediate image onto a transfer medium such as paper. For example, assuming that paper is used as a transfer medium, the surface of the intermediate transfer member preferably has a Duro A hardness (durometer type A hardness) according to JIS K6253 of 10 degrees or more and 100 degrees or less, preferably 20 degrees or more. More preferably, it is 60 degrees or less. The material of the surface layer member constituting the surface layer of the intermediate transfer member is preferably metal, ceramics, resin, or the like. Among them, polybutadiene rubber, nitrile rubber, chloroprene rubber, silicone rubber, fluorine rubber, fluorosilicone rubber, urethane rubber, styrene elastomer, olefin elastomer, vinyl chloride elastomer, ester elastomer, amide elastomer Polyether, polyester, polystyrene, polycarbonate, siloxane compound, and perfluorocarbon compound are preferable. The surface layer member may be formed by laminating a plurality of materials. For example, a material in which silicone rubber is laminated on an endless belt-like urethane rubber sheet, a material in which silicone rubber is laminated on a polyethylene terephthalate film, a material in which a siloxane compound is formed on a urethane rubber sheet, and the like can be mentioned.

  The surface of the intermediate transfer member may be subjected to surface treatment. Examples of the surface treatment include flame treatment, corona treatment, plasma treatment, polishing treatment, roughening treatment, active energy ray irradiation treatment, ozone treatment, surfactant treatment, and silane coupling treatment. A plurality of these may be combined and used.

  Further, from the viewpoint of suppressing the flow of the intermediate image on the intermediate transfer member, the arithmetic average roughness defined by JIS B 0601: 2001 on the surface of the intermediate transfer member is preferably 0.01 μm or more and 3 μm or less. Furthermore, the contact angle of water on the surface of the intermediate transfer member is preferably from 50 degrees to 110 degrees, and more preferably from 60 degrees to 100 degrees.

[Ink application process]
In the ink applying step, the ink is applied to the intermediate transfer body. As a means for applying ink to the intermediate transfer member, it is preferable to use an ink jet method. In particular, it is more preferable to apply thermal energy to the ink to discharge the ink from the discharge port of the recording head.

  As an ink jet recording head, a line head, a serial head, or the like can be used. In the inkjet head of the line head form, the ink discharge ports are arranged in a direction (axial direction in the case of a drum shape) orthogonal to the rotation direction of the intermediate transfer member. The serial head is a head that scans and records the head in the direction orthogonal to the rotation direction of the intermediate transfer member.

[Liquid composition application step]
In the liquid composition application step, the liquid composition is applied to the intermediate transfer member. Examples of the means for applying the liquid composition to the intermediate transfer member include application methods such as a roller coating method, a bar coating method, and a spray coating method, and an ink jet method. In particular, it is preferable to use a coating method. In the intermediate transfer type image recording method, it is preferable to provide a liquid composition application step prior to the ink application step.

[Liquid removal process]
After the intermediate image is formed by applying the ink and the liquid composition, and prior to the transfer step, there may be a liquid removal step of removing the liquid from the intermediate image formed on the intermediate transfer member. If the intermediate image contains an excessive amount of liquid, the excess liquid may overflow in the transfer process, which may cause deterioration in image quality of the obtained image. Therefore, it is preferable to remove excess liquid from the intermediate image by the liquid removing step. Examples of the method for removing the liquid include a heating method, a method of blowing low-humidity air, a method of reducing the pressure, a natural drying method, and a method combining these.

[Transfer process]
In the transfer step, the intermediate transfer body is brought into contact with the intermediate image recorded on the intermediate transfer body to transfer the intermediate transfer body to the transfer medium, and the image is recorded on the transfer medium. When the intermediate image is transferred to the transfer medium, it is preferable to use a pressure roller, for example, and press from both sides of the intermediate transfer member and the transfer medium. By applying pressure, the transfer efficiency can be improved. At this time, pressure may be applied in multiple stages.

  As described above, in recent years, with the increase in demand for high-speed recording, it is required to achieve high transfer efficiency even at high transfer speeds. Therefore, in the present invention, the transfer speed means the transfer speed of the transfer medium, preferably 1.0 m / second or more, and more preferably 2.0 m / second or more.

  In addition, it is preferable to heat the intermediate image at the time of transfer. Examples of the method for heating the intermediate image include a method in which the pressure roller is heated to a predetermined transfer temperature, and a method in which a separate heater is provided. The heating temperature of the pressure roller in the transfer step is preferably set according to the resin particles used, but more preferably 25 ° C. or more and 200 ° C. or less.

<Transfer medium>
In the present invention, not only paper used for general printing but also cloth, plastic, film and the like are widely included as a transfer medium. The transfer medium may be previously cut into a desired size. Alternatively, a sheet wound in a roll shape may be used and cut into a desired size after image recording.

[Fixing process]
You may have the fixing process which pressurizes the transfer medium in which the intermediate image was transferred with a roller after a transfer process. By applying pressure, the smoothness of the image can be enhanced.

  In addition, when the transfer medium on which the image has been transferred is pressed with a roller, the roller is preferably heated. By pressurizing with a heated roller, the fastness of the image can be enhanced, and further, the glossiness of the image obtained by adjusting the heating temperature can be controlled.

[Cleaning process]
You may have the cleaning process of cleaning the surface of an intermediate transfer body after a transfer process. As a method of cleaning the intermediate transfer member, any of the conventionally used methods can be used. Specifically, a method of applying the cleaning liquid to the intermediate transfer member in the form of a shower, a method of wiping a wet Molton roller in contact with the intermediate transfer member, a method of bringing the intermediate transfer member into contact with the cleaning liquid surface, and a wiper blade Examples include a method of wiping off the residue of the intermediate transfer member, a method of applying various types of energy to the intermediate transfer member, and a method of combining a plurality of these methods.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited in any way by the following examples as long as the gist thereof is not exceeded. In the following description of the examples, "part" is on a mass basis unless otherwise noted.

[Preparation of ink]
<Preparation of pigment dispersion>
(Preparation of black pigment dispersion)
10 parts of carbon black (product name: Monac 1100, manufactured by Cabot), aqueous resin solution (styrene-ethyl acrylate-acrylic acid copolymer, acid value 150, weight average molecular weight 8,000, resin content 20.0 mass) 15 parts aqueous solution neutralized with aqueous potassium hydroxide solution) and 75 parts pure water were mixed, charged into a batch type vertical sand mill (made by IMEX), and filled with 200 parts of 0.3 mm diameter zirconia beads, Dispersion treatment was performed for 5 hours while cooling with water. The dispersion was centrifuged to remove coarse particles, to obtain a black pigment dispersion having a pigment content of 10.0% by mass.

(Preparation of cyan pigment dispersion)
Instead of carbon black, C.I. I. A cyan pigment dispersion having a pigment content of 10.0% by mass was obtained in the same manner as in the above (preparation of black pigment dispersion) except that CI Pigment Blue 15: 3 was used.

(Preparation of magenta pigment dispersion)
Instead of carbon black, C.I. I. A magenta pigment dispersion having a pigment content of 10.0% by mass was obtained in the same manner as in the above (preparation of black pigment dispersion) except that CI Pigment Red 122 was used.

<Preparation of resin particle dispersion>
(Preparation of resin particle dispersion 1)
In a solution obtained by mixing 51.9 parts of ion-exchanged water and 0.1 part of potassium persulfate, 35.0 parts of methyl methacrylate, 10.0 parts of methacrylic acid, and 3.0 parts of Nikkol BC15 (manufactured by Nikko Chemicals) After mixing and emulsifying, the polymerization reaction was carried out while stirring at 80 ° C. in a nitrogen atmosphere while being dropped over 3 hours. Then, it cooled to room temperature, ion-exchange water and potassium hydroxide aqueous solution were added, and the resin particle dispersion 1 whose resin content is 30.0 mass% was obtained.

(Preparation of resin particle dispersion 2)
18 parts of ethyl methacrylate, 2 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 78 parts of a 6% aqueous solution of a styrene-butyl acrylate-acrylic acid copolymer (acid value 130 mgKOH / g, weight average molecular weight 7,000) and stirred for 0.5 hours. Next, ultrasonic waves were irradiated for 3 hours with an ultrasonic irradiator. Subsequently, a polymerization reaction was performed at 80 ° C. for 4 hours in a nitrogen atmosphere, and after filtration at room temperature, filtration was performed to obtain a resin particle dispersion 2 having a resin content of 20.0% by mass.

<Preparation of compounds represented by general formulas (1) and (2)>
The compounds shown in Table 1 were prepared. As a comparative example, a compound represented by the following general formula (2) was also prepared.

(In general formula (2), R represents an alkyleneoxy group, and n, m, and l each independently represents an integer of 1 or more.)

In the table, “ethyleneoxy group: propyleneoxy group = 1: 1, 2: 1” means that the molar ratio of ethyleneoxy group to propyleneoxy group contained in R is 1: 1, 2: 1. Indicates

<Preparation of ink>
(Preparation of black ink)
The resin particle dispersion obtained as described above and the pigment dispersion were mixed with the following components. The balance of ion-exchanged water is such that the total of all components constituting the ink is 100.0% by mass.
Pigment dispersion (coloring material content is 10.0% by mass) 40.0% by mass
-Resin particle dispersion A mass% in Table 3
・ Glycerin 7.0% by mass
-Polyethylene glycol (number average molecular weight: 1,000) 3.0 mass%
-Compound represented by general formula (1) or (2) B mass% of Table 3
Surfactant: Acetylenol E 100 (manufactured by Kawaken Fine Chemical Co., Ltd.) C mass% in Table 3
-Ion-exchanged water The remaining portion was sufficiently stirred and dispersed, followed by pressure filtration with a micro filter (manufactured by Fujifilm) having a pore size of 3.0 µm to prepare each black ink.

(Preparation of cyan ink and magenta ink)
Cyan inks 1 to 38 and magenta inks 1 to 38 were prepared in the same manner as described above (preparation of black ink) except that a cyan pigment dispersion or a magenta pigment dispersion was used instead of the black pigment dispersion.

<Preparation of liquid composition>
Each component described in Table 4 was mixed and sufficiently stirred and dispersed, and then pressure filtration was performed with a microfilter (manufactured by Fuji Film) having a pore size of 3.0 μm to prepare each liquid composition. “AE100” in the table is acetylene glycol E100 (manufactured by Kawaken Fine Chemicals), a nonionic surfactant obtained by adding ethylene oxide to acetylene glycol and acetylene glycol, and “F444” is a perfluoroalkylethylene oxide adduct. Megafuck F 444 (made by DIC).

[Evaluation]
The image quality was evaluated by recording the image by the method described later and confirming the occurrence of image movement and the variation in dot diameter. In the present invention, in the following evaluations, the image quality is low when the C rank is in any of them, which is an unacceptable level. In the image recording apparatus used in this example, 3.0 n (nano) g ink droplets were applied to a unit area of 1 / 1,200 inch × 1 / 1,200 inch with a resolution of 1,200 dpi × 1,200 dpi. The condition for applying one drop is defined as a recording duty of 100%.

[1] Example 1 30,37,38, Comparative Examples 1 to 3,5～ 11 (directly imageable image recording method)
The liquid composition and ink obtained above were filled in an ink cartridge, and mounted in a direct-drawing type image recording apparatus in the combination described in Table 5.

(Dot diameter variation)
First, using the image recording apparatus, the liquid composition obtained above was applied to a recording medium: Pearl Coat (manufactured by Mitsubishi Paper Industries) at an application amount of 1.0 g / m ² using an application roller. Then, cyan ink was ejected from an inkjet recording head onto a recording medium coated with the liquid composition, and an image with a recording duty of 100% (solid image of 5 cm × 5 cm) was recorded. Furthermore, black ink was applied to the area where the solid image of cyan ink is recorded and the area where the solid image is not recorded. Then, to measure the dot diameter d ₂ of the black ink in the area where the solid image of cyan ink is not recorded with the dot diameter d ₁ of the black ink in the area being recorded, a dot diameter ratio (= 100 × | d ₁ -D ₂ | / d ₁ ) was calculated and evaluated according to the following criteria. The evaluation results are shown in Table 5.
A: The dot diameter ratio was less than 5 A: The dot diameter ratio was 5 or more and less than 10 B: The dot diameter ratio was 10 or more and less than 20, C: The dot diameter ratio was 20 or more and less than 40 D: The dot diameter ratio was 40 or more.

(Occurrence of image movement)
First, using the image recording apparatus, the liquid composition obtained above was applied to a recording medium: Pearl Coat (manufactured by Mitsubishi Paper Industries) at an application amount of 1.0 g / m ² using an application roller. Then, black ink, cyan ink, and magenta ink are ejected from the ink jet recording head onto the recording medium coated with the liquid composition, and the recording duty is 300% (the recording duty of each ink is 100%) (5 cm). A solid image of × 5 cm was recorded. The obtained image was observed with a microscope to check whether color loss occurred. When image movement occurs, color loss occurs in the solid image. Evaluation criteria are as follows. The evaluation results are shown in Table 5.
A: No color loss occurred B: There was a portion where color loss occurred, but it was at a level that was not noticeable C: Color loss occurred remarkably.

Claims (29)

A step of applying the ink containing the pigment and the anionic resin particles to the recording medium, and a region where the ink is applied to the liquid composition that destabilizes the dispersion state of the pigment or the anionic resin particles in the ink And applying the recording medium to the recording medium so as to at least partially overlap the recording medium.
The content of the anionic resin particles is 1% by mass or more based on the total mass of the ink,
The image recording method characterized in that the ink further contains a compound represented by the following general formula (1).

(In General Formula (1), R represents an alkyleneoxy group, n and p are each independently an integer of 9 to 20, m and q are each independently an integer of 1 or more, and l is an integer of 4 to 250. .)   The image recording method according to claim 1, wherein the content of the compound represented by the general formula (1) is 0.2% by mass or more based on the total mass of the ink.   The image recording method according to claim 1, wherein the content of the compound represented by the general formula (1) based on the total mass of the ink is 0.5% by mass or more and 10.0% by mass or less. The image recording method according to any one of claims 1 to 3, wherein the content of the anionic resin particles based on the total mass of the ink is 3% by mass or more. 4. The image recording method according to claim 1, wherein the content of the anionic resin particles based on the total mass of the ink is 5% by mass or more and 15% by mass or less. The content of the anionic resin particles based on the total mass of the ink is 0.5 times or more and 20.0 times or less by mass ratio with respect to the content of the compound represented by the general formula (1). The image recording method according to any one of claims 1 to 5 . Said liquid composition, an image recording method according to any one of claims 1 to 6 containing at least one selected from polyvalent metal ions and organic acids. The image recording method according to any one of claims 1 to 7 , wherein the recording medium is an intermediate transfer member. The 50% cumulative volume average particle diameter _{(D 50)} of the anionic resin particles, an image recording method according to any one of claims 1 to 8 is 10nm or more 1,000nm or less. An ink used for the image recording method according to any one of claims 1 to 9 . A step of applying the ink containing the pigment and the anionic resin particles to the recording medium, and a region where the ink is applied to the liquid composition that destabilizes the dispersion state of the pigment or the anionic resin particles in the ink And applying the recording medium to the recording medium so as to at least partially overlap the recording medium.
The content of the anionic resin particles is 1% by mass or more based on the total mass of the ink,
An image recording method, wherein the liquid composition contains a compound represented by the following general formula (1).

(In General Formula (1), R represents an alkyleneoxy group, n and p are each independently an integer of 9 to 20, m and q are each independently an integer of 1 or more, and l is an integer of 4 to 250. .) The image recording method according to claim 11 , wherein the content of the compound represented by the general formula (1) is 5.0% by mass or more based on the total mass of the liquid composition. The image recording method according to claim 11 , wherein the content of the compound represented by the general formula (1) based on the total mass of the liquid composition is 20.0 mass% or more and 70.0 mass% or less. 14. The image recording method according to claim 11, wherein the content of the anionic resin particles based on the total mass of the ink is 3% by mass or more. The image recording method according to any one of claims 11 to 13, wherein the content of the anionic resin particles is 5% by mass or more and 15% by mass or less based on the total mass of the ink. Liquid compositions, image recording method according to any one of claims 11 to 15 containing at least one selected from polyvalent metal ions and organic acids. The image recording method according to any one of claims 11 to 16 , wherein the recording medium is an intermediate transfer member. The 50% cumulative volume-average particle diameter of the anionic resin particles _{(D 50)} An image recording method according to any one of claims 11 to 17 is 10nm or more 1,000nm or less. A liquid composition for use in the image recording method according to any one of claims 11 to 18 . A step of applying a clear ink containing anionic resin particles to a recording medium, and a liquid composition that destabilizes the dispersion state of the anionic resin particles in the clear ink, and at least a region to which the clear ink is applied An image recording method comprising the steps of: applying to the recording medium so as to partially overlap;
The content of the anionic resin particles is 1% by mass or more based on the total mass of the clear ink,
The clear ink further contains a compound represented by the following general formula (1):

(In General Formula (1), R represents an alkyleneoxy group, n and p are each independently an integer of 9 to 20, m and q are each independently an integer of 1 or more, and l is an integer of 4 to 250. .) The image recording method according to claim 20 , wherein the content of the compound represented by the general formula (1) is 0.2% by mass or more based on the total mass of the clear ink. 21. The image recording method according to claim 20 , wherein the content of the compound represented by the general formula (1) based on the total mass of the clear ink is 0.5% by mass or more and 10.0% by mass or less. The image recording method according to any one of claims 20 to 22, wherein the content of the anionic resin particles is 3% by mass or more based on the total mass of the clear ink. The image recording method according to any one of claims 20 to 22, wherein the content of the anionic resin particles is 5% by mass or more and 15% by mass or less based on the total mass of the clear ink. The content of the anionic resin particles based on the total mass of the clear ink is 0.5 to 20.0 times by mass ratio with respect to the content of the compound represented by the general formula (1). The image recording method according to any one of claims 20 to 24 . The image recording method according to any one of claims 20 to 25 , wherein the liquid composition contains at least one selected from polyvalent metal ions and organic acids. The image recording method according to any one of claims 20 to 26 , wherein the recording medium is an intermediate transfer member. The 50% cumulative volume average particle diameter _{(D 50)} of the anionic resin particles, an image recording method according to any one of claims 20 to 27 is 10nm or more 1,000nm or less. 29. A clear ink for use in the image recording method according to any one of claims 20 to 28 .