JP7035603B2 - Image forming device, image forming method, ink and printed matter - Google Patents

Description

The present invention relates to an image forming apparatus, an image forming method, an ink and a printed matter.

The inkjet recording method is a recording method in which ink droplets are directly ejected from a very fine nozzle onto a recording medium and adhered to obtain characters or images.
According to the inkjet recording method, not only the noise of the apparatus to be used is small and the operability is good, but also the colorization is easy and the plain paper can be used as the recording medium. Therefore, it is widely used as an output device in offices and homes.
On the other hand, even in industrial applications, it is expected that it will be used as an output machine for digital printing due to the improvement of inkjet technology, and printing machines capable of recording on non-absorbable recording media using solvent ink or UV ink are actually on the market. It has been. However, in recent years, the demand for water-based inks has been increasing due to environmental friendliness.

As water-based inks for inkjet, inks whose printing target is special paper such as plain paper or photographic glossy paper have been developed for a long time. It is widely known to add resin particles to ink for the purpose of ensuring fixability on a recording medium and enhancing image fastness.

Further, in order to suppress a defect (blocking) in which the image surface adheres to the laminated recording medium when the output images are laminated at a high temperature and the image is lost when the recording medium is taken out again, the glass transition point. It is known to add resin particles having a high glass transition point, and in particular, as resin particles having a high glass transition point, use a resin having a polycyclic alicyclic hydrocarbon group (isobonyl group, etc.) in its side chain. (See, for example, Patent Documents 1 to 5).
However, when an ink using such a resin is used, the image may be easily damaged due to mechanical stress such as bending of the recording medium with respect to the image after fixing.

An object of the present invention is to provide an image forming apparatus capable of suppressing blocking and image defect due to mechanical stress such as bending of a recording medium for an image after fixing.

The above problem is solved by the following configuration 1).
1) Inking means for applying ink to a recording medium to form an image, and
A drying means for drying the ink and
In an image forming apparatus having
The ink contains at least an emulsion in which an aqueous medium, a coloring material, an alcohol compound having an alicyclic structure, and a resin are dispersed.
The resin contains a resin having a polycyclic alicyclic hydrocarbon group.
An image forming apparatus , wherein the alcohol compound having an alicyclic structure is cyclohexanedimethanol, and is contained in the ink in an amount of 0.1% by mass or more and 0.5% by mass or less .

According to the present invention, it is possible to provide an image forming apparatus capable of suppressing blocking and image defect due to mechanical stress such as bending of a recording medium for an image after fixing.

It is a schematic diagram of the inkjet recording apparatus for demonstrating the image forming apparatus and the image forming method of this invention. It is a schematic diagram which shows an example of the liquid discharge head used in the inkjet recording apparatus. It is an enlarged schematic diagram which shows an example of the liquid discharge head used in the inkjet recording apparatus.

As a result of diligent studies by the present inventors, the reason why the effect of the present invention is exhibited is considered as follows.
Since the resin particles having a high glass transition point are thermally stable, there is almost no change in the structure or shape in each process in the image forming apparatus. Furthermore, since the polycyclic alicyclic hydrocarbon group has high hydrophobicity, it does not swell with water, which is the main component of the ink, or with an alcohol-based solvent, so that the image formed by the ink is heated. The state of the particles is maintained even in the process of drying with warm air. Therefore, if these particles are present on the surface of the image completed through the image forming apparatus, the thermal stability of the image is ensured and defects such as blocking are eliminated.
However, if the particles have a well-defined interface and the particles exist independently of each other, the interface becomes mechanically fragile and mechanically stresses the finished image. If this is the case, it is considered that peeling occurs at the particle interface, resulting in image loss.

In the present invention, an alcohol compound (alicyclic alcohol) having an alicyclic structure is present in the ink. In this case, the alicyclic alcohol is dissolved in the liquid phase containing water as the main component in the ink state, but when the ink transferred onto the recording medium reaches the drying process by heating or warm air, the water becomes ink. By evaporating from the above, the concentration of the alicyclic alcohol increases and it precipitates as a liquid, and at the same time, it permeates from the surface of the resin particles having a polycyclic alicyclic hydrocarbon group and temporarily plasticizes the vicinity of the surface. It is considered that the plasticization caused by the alicyclic alcohol is due to the high affinity for the resin due to the similarity of the cyclic structure with the alicyclic hydrocarbon group of the resin.
A part of the boundary surface of the resin particles having a plasticized polycyclic alicyclic hydrocarbon group is bonded and adhered to another resin particle or another ink constituent material. As the drying progresses, the alicyclic alcohol also vaporizes and goes out of the system, so that the glass transition point of the resin constituting the resin particles having the replasticized polycyclic alicyclic hydrocarbon group is It rises and the thermal stability of the image is guaranteed.
As a result, it is considered that the obtained image is imparted with resistance to mechanical stress while ensuring thermal stability.

<Ink>
Hereinafter, the organic solvent, water, coloring material, resin, additive, etc. used for the ink will be described.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and a water-soluble organic solvent can be used. Examples thereof include ethers such as polyhydric alcohols, polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines and sulfur-containing compounds.
Specific examples of the water-soluble organic solvent include, for example, ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 1,4-butane. Diol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol , 2,4-Pentanediol, 1,5-Pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,3-hexanediol, 2,5-hexanediol, 1,5-hexanediol, Glycerin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl- Polyhydric alcohols such as 1,3-pentanediol and petriol, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, propylene glycol monoethyl Polyhydric alcohol alkyl ethers such as ethers, polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone. , 1,3-Dimethyl-2-imidazolidinone, ε-caprolactam, γ-butyrolactone and other nitrogen-containing heterocyclic compounds, formamide, N-methylformamide, N, N-dimethylformamide, 3-methoxy-N, N- Amidos such as dimethylpropionamide, 3-butoxy-N, N-dimethylpropionamide, amines such as monoethanolamine, diethanolamine and triethylamine, sulfur-containing compounds such as dimethylsulfoxide, sulfolane and thiodiethanol, propylene carbonate and ethylene carbonate. And so on.
It is preferable to use an organic solvent having a boiling point of 250 ° C. or lower because it not only functions as a wetting agent but also has good drying properties.

Polyol compounds having 8 or more carbon atoms and glycol ether compounds are also preferably used. Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
Specific examples of the glycol ether compound include polyhydric alcohol alkyls such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether. Ethers; Examples thereof include polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

A polyol compound having 8 or more carbon atoms and a glycol ether compound can improve the permeability of ink when paper is used as a recording medium.

The content of the organic solvent in the ink is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10% by mass or more and 60% by mass or less from the viewpoint of ink drying property and ejection reliability. More preferably, it is 20% by mass or more and 60% by mass or less.

<Water>
The content of water in the ink is not particularly limited and may be appropriately selected depending on the intended purpose, but from the viewpoint of ink drying property and ejection reliability, it is preferably 10% by mass or more and 90% by mass or less, and 20% by mass. % To 60% by mass is more preferable.

<Color material>
The coloring material is not particularly limited, and pigments and dyes can be used.
As the pigment, an inorganic pigment or an organic pigment can be used. These may be used alone or in combination of two or more. Further, a mixed crystal may be used.
As the pigment, for example, a black pigment, a yellow pigment, a magenta pigment, a cyan pigment, a white pigment, a green pigment, an orange pigment, a glossy color pigment such as gold or silver, a metallic pigment, or the like can be used.
As inorganic pigments, carbon black produced by known methods such as contact method, furnace method, thermal method, in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow. Can be used.
Examples of organic pigments include azo pigments and polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.). , Dye chelate (for example, basic dye type chelate, acid dye type chelate, etc.), nitro pigment, nitroso pigment, aniline black and the like can be used. Among these pigments, those having a good affinity with a solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
As a specific example of the pigment, for black, carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11) , Metals such as titanium oxide, and organic pigments such as aniline black (CI pigment black 1).
Further, for color, C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C.I. I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48: 2, 48: 2 (Permanent Red 2B (Ca)), 48: 3, 48: 4, 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Calcium 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Bengara), 104, 105, 106, 108 ( Cadmium Red), 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. I. Pigment Violet 1 (Rhodamine Lake), 3, 5: 1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15: 1, 15: 2, 15: 3, 15: 4 (phthalocyanine blue), 16, 17: 1, 56, 60, 63, C.I. I. Pigment Greens 1, 4, 7, 8, 10, 17, 18, 36, etc.
The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used, and one type may be used alone or two or more types may be used in combination.
As the dye, for example, C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C.I. I. Acid Red 52,80,82,249,254,289, C.I. I. Acid Blue 9,45,249, C.I. I. Acid Black 1,2,24,94, C.I. I. Food Black 1, 2, C.I. I. Direct Yellow 1,12,24,33,50,55,58,86,132,142,144,173, C.I. I. Direct Red 1,4,9,80,81,225,227, C.I. I. Direct Blue 1,2,15,71,86,87,98,165,199,202, C.I. I. Dilekdo Black 19,38,51,71,154,168,171,195, C.I. I. Reactive Red 14, 32, 55, 79, 249, C.I. I. Reactive Black 3, 4, 35 can be mentioned.

The content of the coloring material in the ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass, from the viewpoint of improving the image density, good fixing property and ejection stability. It is as follows.

In order to disperse the pigment to obtain an ink, a method of introducing a hydrophilic functional group into the pigment to obtain a self-dispersing pigment, a method of coating the surface of the pigment with a resin and dispersing it, and a method of dispersing using a dispersant are used. The method, etc. can be mentioned.
As a method of introducing a hydrophilic functional group into a pigment to obtain a self-dispersing pigment, for example, a method of adding a functional group such as a sulfone group or a carboxyl group to a pigment (for example, carbon) so that the pigment can be dispersed in water. Can be mentioned.
Examples of the method of coating the surface of the pigment with a resin and dispersing the pigment include a method of encapsulating the pigment in microcapsules so that the pigment can be dispersed in water. This can be rephrased as a resin-coated pigment. In this case, it is not necessary that all the pigments blended in the ink are coated with the resin, and the uncoated pigments and the partially coated pigments are dispersed in the ink as long as the effect of the present invention is not impaired. May be.
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular-weight dispersant and high-molecular-weight dispersant represented by a surfactant.
As the dispersant, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant and the like can be used depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Oil & Fat Co., Ltd. and Naphthalene sulfonic acid Na formalin condensate can also be suitably used as a dispersant.
The dispersant may be used alone or in combination of two or more.

<Pigment dispersion>
It is possible to obtain an ink by mixing a material such as water or an organic solvent with a pigment. It is also possible to produce an ink by mixing a material such as water or an organic solvent with a pigment dispersion obtained by mixing a pigment and other water or a dispersant.
The pigment dispersion is obtained by mixing and dispersing water, a pigment, a pigment dispersant, and other components as necessary, and adjusting the particle size. A disperser may be used for dispersion.
The particle size of the pigment in the pigment dispersion is not particularly limited, but the maximum frequency is 20 nm or more in terms of the maximum number because the dispersion stability of the pigment is good and the image quality such as ejection stability and image density is also high. It is preferably 500 nm or less, and more preferably 20 nm or more and 150 nm or less. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).
The content of the pigment in the pigment dispersion is not particularly limited and may be appropriately selected depending on the intended purpose. However, good ejection stability can be obtained and the image density is increased by 0.1 mass. % Or more and 50% by mass or less are preferable, and 0.1% by mass or more and 30% by mass or less are more preferable.
It is preferable that the pigment dispersion is degassed by filtering coarse particles with a filter, a centrifuge, or the like, if necessary.

<Alcohol compound having an alicyclic structure>
The alcohol compound having an alicyclic structure in the present invention can be used without particular limitation. In particular,
Cyclobutanemethanol, cyclopentanol, cyclopentanmethanol, cyclopentandimethanol, cyclopentanethanol, cyclohexanol, 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 4-methylcyclohexanol, cyclohexanemethanol, Cyclohexaneethanol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, cyclohexane-1,4-dimethanol, 1,3,5-cyclohexanetriol, 1-adamantanol, 2-adamantanol and the like can be mentioned. Those having a cis form and a trans form may be any of them or a cis-, trans-mixture.
Among these, 1,2-cyclohexanediol, 1,4-cyclohexanediol, and cyclohexane-1,4-di, which can be appropriately dissolved in water-based inks and have high affinity for resins having a polycyclic alicyclic hydrocarbon group. Methanol is preferred, and cyclohexane-1,4-dimethanol is particularly preferred. Further, the effect of the present invention is maximized when the number of carbon atoms constituting the alicyclic ring is the same as the number of carbon atoms constituting one ring of the polycyclic alicyclic hydrocarbon group contained in the resin structure. It is preferable because it is expressed in.

The content of the alcohol compound having an alicyclic structure in the ink of the present invention is, for example, 0.05% by mass or more and 10% by mass or less, preferably 0.1% by mass or more and 2% by mass or less, and 0. More preferably, it is 1% by mass or more and 0.5% by mass or less.

<Resin>
The resin used in the present invention can improve the blocking resistance of an image by having at least a polycyclic alicyclic hydrocarbon group. Examples of the polycyclic alicyclic hydrocarbon group include a bicyclohexyl group, a norbornyl group, an isobornyl group, a dicyclopentanyl group, an adamantyl group, a decahydronaphthalenyl group, a hydridenanol group and the like.

Of these, an isobornyl group is preferable from the viewpoint of further improving the effect of the present invention.

The type of the resin having a polycyclic alicyclic hydrocarbon group is not particularly limited and may be appropriately selected depending on the intended purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, etc. Examples thereof include styrene resin, butadiene resin, styrene-butadiene resin, vinyl chloride resin, acrylic styrene resin, acrylic silicone resin, and acrylic resin, acrylic styrene resin, and acrylic silicone resin are preferable. Styrene-based resins are even more preferred.

As a method for obtaining an acrylic resin having a polycyclic alicyclic hydrocarbon group, it can be obtained by polymerizing a monomer having a polycyclic alicyclic hydrocarbon group with another monomer, if necessary. ..
Examples of the monomer having a polycyclic alicyclic hydrocarbon group include isobornyl acrylate, isobornyl methacrylate, norbornyl acrylate, norbornyl methacrylate, adamantyl acrylate, adamantyl methacrylate, dicyclopentanyl acrylate, and dicyclopenta. Nyl methacrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate and the like can be mentioned. As described above, the polycyclic alicyclic hydrocarbon group in the resin used in the present invention is preferably derived from a monomer having a (meth) acryloyl group. These may be used alone or in combination of two or more. From the viewpoint of fixability, blocking resistance, and mechanical stress resistance of images, it is preferable to contain isobornyl methacrylate and adamantyl methacrylate.

In addition, the fixing property, blocking resistance, and ejection stability of the ink are improved, and the dispersion stability for using the resin having a polycyclic alicyclic hydrocarbon group as resin particles by dispersing it in an aqueous medium is enhanced. For the purpose, conventionally known monomers can be used together.
In particular,
(Meta) acrylic acid, (anhydrous) maleic acid, maleic acid monoalkyl ester, fumaric acid, fumaric acid monoalkyl ester, crotonic acid, itaconic acid, itaconic acid monoalkyl ester, itaconic acid glycol monoether, citraconic acid, citraconic acid Monomer having a carboxyl group such as monoalkyl ester,
Vinyl sulfonic acid, (meth) allyl sulfonic acid, methyl vinyl sulfonic acid, styrene sulfonic acid; and alkyl derivatives thereof having 2 to 24 carbon atoms, such as α-methylstyrene sulfonic acid; sulfo (hydroxy) alkyl- (meth) acrylate. Alternatively, (meth) acrylamide, for example, sulfopropyl (meth) acrylate, 2-hydroxy-3- (meth) acryloxypropyl sulfonic acid, 2- (meth) acryloylamino-2,2-dimethylethanesulfonic acid, 2-( Meta) acryloyloxyetane sulfonic acid, 3- (meth) acryloyloxy-2-hydroxypropanesulfonic acid, 2- (meth) acrylamide-2-methylpropanesulfonic acid, 3- (meth) acrylamide-2-hydroxypropanesulfonic acid , Alkyl (3 to 18 carbon atoms) allyl sulfosuccinic acid, poly (n = 2 to 30) oxyalkylene (ethylene, propylene, butylene: alone, random, block may be used) mono (meth) acrylate sulfate ester [poly (n) = 5 to 15) Oxypropylene monomethacrylate sulfate ester, etc.], a monomer having a sulfonic acid or sulfate group, such as polyoxyethylene polycyclic phenyl ether sulfate ester,
Methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, tert-butyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, decyl acrylate, lauryl acrylate, palmityl acrylate. , Mystylyl acrylate, stearyl acrylate, behenyl acrylate, methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, nonyl Examples thereof include acrylic acid or methacrylic acid ester monomers such as methacrylate, decyl methacrylate, lauryl methacrylate, palmityl methacrylate, mysticyl methacrylate, stearyl methacrylate and behenyl methacrylate.

Further, in addition to the resin having a polycyclic alicyclic hydrocarbon group, a conventionally known resin may be used in combination. In particular, by using a resin having a glass transition temperature lower than that of a resin having a polycyclic alicyclic hydrocarbon group, the fixability of the ink to the recording medium can be improved. Such a resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene-butadiene. Examples thereof include based resins, vinyl chloride resins, acrylic styrene resins, and acrylic silicone resins. Polycyclic alicyclic hydrocarbon groups are used in that the formed printed image is less likely to cause interface destruction with a resin having a polycyclic alicyclic hydrocarbon group when subjected to mechanical stress. It is preferable that at least a part of the main chain and the resin having the same structure have the same structure, and specifically, a resin having an acrylic resin structure such as an acrylic resin, an acrylic styrene resin, and an acrylic silicone resin is preferable.

<Resin emulsion>
The resin in the present invention is used in an ink in an emulsion state dispersed in an aqueous medium.
The method for obtaining an emulsion is not particularly limited, but for example, by a polymerization method such as an emulsion polymerization method, a suspension polymerization method, a seed polymerization method, a dispersion polymerization method, or a miniemulsion polymerization method, the resin fine particles are directly formed into an aqueous medium. There are a method of obtaining an emulsion dispersed therein, and a method of producing a resin by a polymerization method such as a solution polymerization method or a mass polymerization method and then emulsifying.
Regarding the latter method, a method of further dissolving the resin in a solvent and then adding an aqueous medium while stirring to obtain an emulsion by phase inversion emulsification, a method of dissolving the resin in a solvent and then spraying. There are a method of making fine particles and dispersing them in an aqueous medium to obtain an emulsion, a method of pulverizing a resin with a pulverizer into fine particles, and dispersing the resin in an aqueous medium to obtain an emulsion. When used as an ink for inkjet, the dispersed particle size of the resin is preferably in the range of 10 nm or more and 1,000 nm or less, and in order to obtain such a resin emulsion, an emulsion polymerization method or a miniemulsion polymerization method, etc. A method of obtaining an emulsion by inversion emulsification is preferable.

The content of the resin is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of fixability and storage stability of the ink, 1% by mass or more and 30% by mass or less with respect to the total amount of the ink. Is preferable, and more preferably 2% by mass or more and 20% by mass or less.

The particle size of the solid content in the ink is not particularly limited and can be appropriately selected according to the purpose, but from the viewpoint of improving image quality such as ejection stability and image density, the maximum frequency in terms of the maximum number of inks. Is preferably 20 nm or more and 1000 nm or less, and more preferably 20 nm or more and 150 nm or less. The solid content includes resin particles, pigment particles, and the like. The particle size can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

<Additives>
If necessary, a surfactant, an antifoaming agent, an antiseptic / antifungal agent, a rust preventive agent, a pH adjuster and the like may be added to the ink.

<Surfactant>
As the surfactant, any of a silicone-based surfactant, a fluorine-based surfactant, an amphoteric surfactant, a nonionic surfactant, and an anionic surfactant can be used.
The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, single-ended modified polydimethylsiloxane, side chain double-ended modified polydimethylsiloxane, and the like. Those having an oxyethylene group and a polyoxyethylene polyoxypropylene group are particularly preferable because they exhibit good properties as an aqueous surfactant. Further, as the silicone-based surfactant, a polyether-modified silicone-based surfactant can also be used, and examples thereof include compounds in which a polyalkylene oxide structure is introduced into the Si portion side chain of dimethylsiloxane.
Examples of the fluorine-based surfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate ester compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. Polyoxyalkylene ether polymer compounds are particularly preferred because they have low foaming properties. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid and perfluoroalkyl sulfonic acid salt. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylic acid salt. The polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain includes a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain and a perfluoroalkyl ether group in the side chain. Examples thereof include salts of polyoxyalkylene ether polymers. The counter ions of the salts in these fluorine-based surfactants include Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , and NH (CH ₂ CH ₂ OH). ₃ etc. can be mentioned.
Examples of the amphoteric tenside include laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, and lauryldihydroxyethylbetaine.
Examples of the nonionic surfactant include polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, and polyoxyethylene sorbitan. Examples thereof include a fatty acid ester and an ethylene oxide adduct of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, lauryl salt, polyoxyethylene alkyl ether sulfate salt and the like.
These may be used alone or in combination of two or more.

The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, side chain-modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, one-ended modified polydimethylsiloxane, side. Examples thereof include polydimethylsiloxane modified at both ends of the chain, and a polyether-modified silicone-based surfactant having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group exhibits good properties as an aqueous surfactant, and is particularly effective. preferable.
As such a surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. As commercially available products, for example, they can be obtained from Big Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Toray Dow Corning Silicone Co., Ltd., Nippon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd., and the like.
The above-mentioned polyether-modified silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a polyalkylene oxide structure represented by the general formula (S-1) may be dimethylpoly. Examples thereof include those introduced into the Si part side chain of siloxane.

一般式（Ｓ－１）

General formula (S-1)

(However, in the general formula (S-1), m, n, a, and b each independently represent an integer, R represents an alkylene group, and R'represents an alkyl group.)
Commercially available products can be used as the above-mentioned polyether-modified silicone-based surfactant, for example, KF-618, KF-642, KF-643 (Shinetsu Chemical Industry Co., Ltd.), EMALEX-SS-5602, SS-. 1906EX (Nippon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Toray Dow Corning Silicone Co., Ltd.), BYK-33, BYK-387 (Big Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.) and the like can be mentioned.

As the fluorine-based surfactant, a compound having 2 to 16 carbon atoms substituted with fluorine is preferable, and a compound having 4 to 16 carbon atoms substituted with fluorine is more preferable.
Examples of the fluorine-based surfactant include a perfluoroalkyl phosphate ester compound, a perfluoroalkylethylene oxide adduct, and a polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain. Among these, the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain is preferable because it has less foaming property, and is particularly a fluorine-based compound represented by the general formula (F-1) and the general formula (F-2). Surfactants are preferred.

一般式（Ｆ－１）

General formula (F-1)

In the compound represented by the general formula (F-1), m is preferably an integer of 0 to 10 and n is preferably an integer of 0 to 40 in order to impart water solubility.
General formula (F-2)
C _n F _{2n + 1-} CH ₂ CH (OH) CH ₂ -O- (CH ₂ CH ₂ O) _a -Y
In the compound represented by the above general formula (F-2), Y is H or CmF _{2m + 1} and m is an integer of 1 to 6, or CH ₂ CH (OH) CH ₂ -CmF _{2m + 1} and m is 4 to 6. It is an integer, or CpH _{2p + 1} and p is an integer of 1 to 19. n is an integer of 1 to 6. a is an integer of 4 to 14.
Commercially available products may be used as the above-mentioned fluorine-based surfactant. Examples of this commercially available product include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Full Lard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Co., Ltd.); Megafuck F-470, F -1405, F-474 (all manufactured by Dainippon Ink and Chemicals Co., Ltd.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by The Chemours Company); FT-110, FT-250, FT-251, FT-400S, FT-150, FT- 400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omniova), Unidyne DSN-403N (manufactured by Daikin Industries Co., Ltd.) Among these, FS-3100, FS-34, FS- of The Chemours Co., Ltd. from the viewpoint of remarkably improving good print quality, particularly color development, permeability to paper, wettability, and leveling property. 300, FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Co., Ltd., Polyfox PF-151N manufactured by Omninova, and Unidyne DSN-manufactured by Daikin Industries Co., Ltd. 403N is particularly preferable.

The content of the surfactant in the ink is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of excellent wettability and ejection stability and improvement in image quality, 0.001 mass is used. % Or more and 5% by mass or less are preferable, and 0.05% by mass or more and 5% by mass or less are more preferable.

<Defoamer>
The defoaming agent is not particularly limited, and examples thereof include a silicone-based defoaming agent, a polyether-based defoaming agent, and a fatty acid ester-based defoaming agent. These may be used alone or in combination of two or more. Among these, a silicone-based defoaming agent is preferable because it has an excellent defoaming effect.

<Preservatives and fungicides>
The antiseptic and antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one and the like.

<Rust inhibitor>
The rust preventive is not particularly limited, and examples thereof include acidic sulfites and sodium thiosulfate.

<pH adjuster>
The pH adjusting agent is not particularly limited as long as the pH can be adjusted to 7 or more, and examples thereof include amines such as diethanolamine and triethanolamine.

The physical characteristics of the ink are not particularly limited and may be appropriately selected depending on the intended purpose. For example, the viscosity, surface tension, pH and the like are preferably in the following ranges.
The viscosity of the ink at 25 ° C. is preferably 5 mPa · s or more and 30 mPa · s or less, preferably 5 mPa · s or more and 25 mPa · s or less, from the viewpoint of improving the print density and character quality and obtaining good ejection properties. More preferred. Here, for the viscosity, for example, a rotary viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) can be used. As the measurement conditions, it is possible to measure at 25 ° C. with a standard cone rotor (1 ° 34'× R24), a sample liquid volume of 1.2 mL, a rotation speed of 50 rpm, and 3 minutes.
The surface tension of the ink is preferably 35 mN / m or less, and more preferably 32 mN / m or less at 25 ° C. from the viewpoint that the ink is preferably leveled on the recording medium and the drying time of the ink is shortened.
The pH of the ink is preferably 7 to 12, and more preferably 8 to 11 from the viewpoint of preventing corrosion of the metal member that comes into contact with the liquid.

<Pretreatment liquid>
The pretreatment liquid contains a flocculant, an organic solvent, and water, and may contain a surfactant, an antifoaming agent, a pH adjuster, an antiseptic / antifungal agent, an anticorrosive agent, and the like, if necessary.
As the organic solvent, surfactant, defoaming agent, pH adjuster, antiseptic and antifungal agent, and rust preventive, the same materials as those used for ink can be used, and other materials used for known treatment liquids can be used. ..
The type of flocculant is not particularly limited, and examples thereof include water-soluble cationic polymers, acids, and polyvalent metal salts.

<Post-treatment liquid>
The post-treatment liquid is not particularly limited as long as it is possible to form a transparent layer. The post-treatment liquid is obtained by selecting and mixing organic solvents, water, resins, surfactants, defoamers, pH adjusters, antiseptic and antifungal agents, rust preventives and the like, if necessary. Further, the post-treatment liquid may be applied to the entire recording area formed on the recording medium, or may be applied only to the area where the ink image is formed.

<Recording medium>
The recording medium used for recording is not particularly limited, and examples thereof include plain paper, glossy paper, special paper, cloth, film, transparency sheet, and general-purpose printing paper.

The recording medium is not limited to that used as a general recording medium, and wallpaper, flooring, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather and the like can be appropriately used. Further, ceramics, glass, metal, or the like can be used by adjusting the configuration of the path for transporting the recording medium.

<Recorded material>
The ink recording material of the present invention comprises an image formed by using the ink of the present invention on a recording medium.
It can be recorded by an inkjet recording device and an inkjet recording method to obtain a recorded material.

<Image forming device and image forming method>
The image forming apparatus of the present invention has an ink applying means for applying ink to a recording medium to form an image and a drying means for drying the ink, and the ink is the ink of the present invention. It is a feature.
Further, the image forming method of the present invention includes an ink applying step of applying ink to a recording medium to form an image and a drying step of drying the ink, and the ink is the ink of the present invention. It is characterized by.

FIG. 1 is a schematic diagram of an inkjet recording device for explaining an image forming apparatus and an image forming method of the present invention. The inkjet recording apparatus has an ink applying means and an applying step of applying ink to a recording medium to form an image, and a drying means and a drying step of drying an aqueous medium contained in the ink applied by heat and air flow. The inkjet recording apparatus 300 includes a recording medium transport unit 301, a pretreatment process unit 302 that applies a pretreatment liquid to the recording medium 203, a pretreatment post-drying unit 303 that dries the recording medium 203 to which the pretreatment liquid is applied, and an image. It is composed of a forming process unit 304, a post-treatment process unit 305 that applies a post-treatment liquid to the recording medium after the image forming process, and a post-treatment drying unit 306 that dries the recording medium 203 to which the post-treatment liquid is applied.
The recording medium transport unit 301 includes a paper feed device 307, a plurality of transport rollers, and a take-up device 308. The recording medium 203 of FIG. 1 is continuous paper (roll paper) wound in a roll shape, and the recording medium 203 is unwound from the paper feed device by a transfer roller, conveyed on a platen, and wound by a take-up device. Be done.

The recording medium 203 transported from the recording medium transport unit 301 is coated with the pretreatment liquid by the pretreatment process unit 302 of FIG. In the inkjet recording method, when an image is formed on a recording medium other than the inkjet paper, quality problems such as bleeding, density, color tone and show-through, and problems related to image fastness such as water resistance and weather resistance occur. As a means for solving this problem, a technique is used to improve image quality by applying a pretreatment liquid having a function of aggregating ink before forming an image on a recording medium.
As the pretreatment step, a coating method in which the above pretreatment liquid is uniformly applied to the surface of the printing paper may be used, and there is no particular limitation. As such a coating method, for example, a blade coating method, a gravure coating method, a gravure offset coating method, a bar coating method, a roll coating method, a knife coating method, an air knife coating method, a comma coating method, a U comma coating method, and an AKKU coating method. , Smoothing coat method, micro gravure coat method, reverse roll coat method, 4 to 5 roll coat method, dip coat method, curtain coat method, slide coat method, die coat method and the like.

Further, as shown in FIG. 1, the pretreatment section may be provided with the pretreatment and post-drying section 303 after the coating step. The pretreatment and post-drying apparatus includes, for example, heat rollers 311, 312 as shown in FIG. According to this device, the continuous paper coated with the pretreatment liquid is conveyed to the heat roller by the conveying roller. The heat roller is heated to a high temperature of 50 to 100 ° C., and the continuous paper coated with the pretreatment liquid evaporates moisture and is dried by the contact heat transfer from the heat roller.

For the recording medium after the pretreatment step, an image corresponding to the image data is formed by the image forming step unit 304.

The image forming process unit 304 is a full-line type head and has four recording heads 304K capable of handling black (K), cyan (C), magenta (M), and yellow (Y) from the upstream side in the recording medium transport direction. , 304C, 304M, 304Y are arranged and configured. For example, the black (K) recording head 304K has four short head units 304K-1, 304K-2, 304K-3, and 304K-4 arranged in a staggered pattern in a direction orthogonal to the transport direction as shown in FIG. The print area width is secured by making it. FIG. 3 is an enlarged view of the head unit 304K-1. As shown in FIG. 3, a large number of printing nozzles 310 are arranged along the longitudinal direction of the head unit 304K-1 on the nozzle surface 309 of the 304K-1 to form a nozzle row. In the present embodiment, the nozzle row is one row, but a plurality of nozzle rows may be provided. The other recording heads 304C, 304M, and 304Y have the same configuration, and the four recording heads 304K, 304C, 304M, and 304Y are arranged in the transport direction while maintaining the same pitch. This makes it possible to form an image over the entire width of the print area with one recording operation.
The types of ink are not limited to K, C, M, and Y, and photo inks such as light cyan can also be applied.

The post-treatment liquid is applied to the recording medium after the image forming step by the post-treatment step unit 305. The post-treatment liquid described later contains a component capable of forming a transparent protective layer on the recording medium.

In the post-processing step in the present embodiment, the image is applied only to a specific part of the image forming region of the recording medium. The coating amount is preferably the optimum amount according to the color of the ink forming the image. More preferably, the coating amount and coating method may be changed according to the type and resolution of the recording medium.
The method for applying the post-treatment liquid is not particularly limited, and various methods are appropriately selected depending on the type of the post-treatment liquid. Any of the same methods as the method can be preferably used. Among these, a method similar to the method of flying the inkjet ink is particularly preferable from the viewpoint of the apparatus configuration and the storage stability of the post-treatment liquid. This post-treatment step is a step of applying a post-treatment liquid containing a transparent resin to the formed image surface so that the amount of dry adhesion is 0.5 g / m ² to 10 g / m ² to form a protective layer. be.

The inkjet recording device 300 has a post-treatment post-treatment drying unit 306 that dries the recording medium 203 to which the post-treatment liquid is applied.
The post-treatment drying section 306 is composed of, for example, heat rollers 313 and 314 as shown in FIG. According to this device, the recording medium (continuous paper) coated with the post-treatment liquid is conveyed to the heat rollers 313 and 314 by the conveying roller. The heat rollers 313 and 314 are heated to a high temperature, and the continuous paper coated with the post-treatment liquid evaporates moisture and is dried by the contact heat transfer from the heat rollers 313 and 314. The drying means is not limited to this, and an infrared drying device, a microwave drying device, a hot air device, or the like can be applied. good.

The use of the ink of the present invention is not particularly limited and may be appropriately selected depending on the intended purpose, and can be applied to, for example, printed matter, paints, coating materials, base materials and the like. Further, it can be used not only as an ink to form two-dimensional characters and images, but also as a three-dimensional modeling material for forming a three-dimensional stereoscopic image (three-dimensional model).
As the three-dimensional modeling apparatus for modeling the three-dimensional object, a known one can be used, and is not particularly limited, but for example, an apparatus provided with ink accommodating means, supply means, ejection means, drying means and the like is used. be able to. The three-dimensional model includes a three-dimensional model obtained by overcoating with ink. Further, a molded product obtained by processing a structure in which ink is applied on a base material such as a recording medium is also included. The molded product is, for example, a sheet-shaped or film-shaped recorded material or structure that has been subjected to molding processing such as heat stretching or punching, and is, for example, an automobile, OA equipment, or electricity. -Suitably used for molding after decorating the surface of electronic devices, meters of cameras, panels of operation parts, etc.

Further, in the terms of the present invention, image formation, recording, printing, printing, etc. are all synonymous.

Recording media, media, and printed matter are all synonymous.

Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples, but the present invention is not limited to the following examples. Further, Examples 4 and 5 are Reference Examples 4 and 5 not included in the present invention.

<Method for producing resin dispersion-A (polycyclic alicyclic hydrocarbon group-containing resin emulsion-A)>
648 g of methyl ethyl ketone, 216 g of methyl methacrylate, 281 g of isobornyl methacrylate and 43 g of methacrylic acid were charged in a reaction vessel equipped with a reflux tube, and the temperature was raised to 75 ° C. under a nitrogen atmosphere with stirring.
After raising the temperature, while continuing stirring, a solution prepared by dissolving 3.32 g of Wako Junyaku Co., Ltd. [V-601] in 45 g of methyl ethyl ketone was added over 15 minutes, and then stirring was continued for 5 hours for polymerization. The reaction was carried out.
After completion of the reaction, 180 g of methyl ethyl ketone was added, and then 120.8 ml of a 1 mol / L KOH aqueous solution was added to bring the temperature to 75 ° C., and then 800 g of ion-exchanged water at 75 ° C. was added to a reaction vessel for phase inversion emulsification. Then, methyl ethyl ketone was distilled off under reduced pressure to obtain a dispersion liquid-A of a resin having an isobornyl group as a polycyclic alicyclic hydrocarbon group. The average particle size (D50) of the resin fine particles in the obtained dispersion was measured and found to be 108 nm.

<Manufacturing method of resin dispersion-B (polycyclic alicyclic hydrocarbon group-containing resin emulsion-B)>
In a reaction vessel equipped with a reflux tube, 648 g of methyl ethyl ketone, 231 g of methyl methacrylate, 265 g of adamantyl methacrylate and 44 g of methacrylic acid were charged, and the temperature was raised to 75 ° C. under a nitrogen atmosphere with stirring.
After raising the temperature, while continuing stirring, a solution prepared by dissolving 3.32 g of Wako Junyaku Co., Ltd. [V-601] in 45 g of methyl ethyl ketone was added over 15 minutes, and then stirring was continued for 5 hours for polymerization. The reaction was carried out.
After completion of the reaction, 180 g of methyl ethyl ketone was added, and then 120.8 ml of a 1 mol / L KOH aqueous solution was added to bring the temperature to 75 ° C., and then 800 g of ion-exchanged water at 75 ° C. was added to a reaction vessel for phase inversion emulsification. Then, methyl ethyl ketone was distilled off under reduced pressure to obtain a dispersion liquid-B of a resin having an adamantyl group as a polycyclic alicyclic hydrocarbon group. The average particle size (D50) of the resin fine particles in the obtained dispersion was measured and found to be 103 nm.

<Manufacturing method of resin dispersion-C (polycyclic alicyclic hydrocarbon group-containing resin emulsion-C)>
648 g of methyl ethyl ketone, 189 g of methyl methacrylate, 307 g of dicyclopentanyl methacrylate and 44 g of methacrylic acid were charged in a reaction vessel equipped with a reflux tube, and the temperature was raised to 75 ° C. under a nitrogen atmosphere with stirring.
After raising the temperature, while continuing stirring, a solution prepared by dissolving 3.32 g of Wako Junyaku Co., Ltd. [V-601] in 45 g of methyl ethyl ketone was added over 15 minutes, and then stirring was continued for 5 hours for polymerization. The reaction was carried out.
After completion of the reaction, 180 g of methyl ethyl ketone was added, and then 120.8 ml of a 1 mol / L KOH aqueous solution was added to bring the temperature to 75 ° C., and then 800 g of ion-exchanged water at 75 ° C. was added to a reaction vessel for phase inversion emulsification. Then, methyl ethyl ketone was distilled off under reduced pressure to obtain a dispersion liquid-C of a resin having a dicyclopentanyl group as a polycyclic alicyclic hydrocarbon group. The average particle size (D50) of the resin fine particles in the obtained dispersion was measured and found to be 103 nm.

<Making ink>
The production of each ink was carried out according to the following procedure.
First, a water-soluble organic solvent, a penetrant, an alcohol compound having an alicyclic structure (alicyclic alcohol), a surfactant, an antifungal agent, and water shown in Table 1 below are mixed and stirred for 1 hour to make them uniform. Was mixed with. A resin dispersion was added to this mixture and stirred for 1 hour, and a pigment dispersion and an antifoaming agent were added and stirred for 1 hour. This dispersion was pressure-filtered with a polyvinylidene fluoride membrane filter having an average pore size of 0.8 μm to remove coarse particles and dust, and an ink was obtained.

* Pigment dispersion: Cabot's black pigment self-dispersion CAB-O-JET300
* Acrylic-silicone resin emulsion: manufactured by Showa Polymer Co., Ltd., Polysol ROY6312, solid content 37.2% by mass, average particle size 171 nm, minimum film forming temperature (MFT) = 20 ° C.
* Polyurethane resin emulsion: DIC Corporation, Hydran APX-101H, solid content 45% by mass, average particle size 160 nm, minimum film forming temperature (MFT) = 20 ° C.
* Surfactant: Fluorosurfactant DSN403N manufactured by Daikin Industries, Ltd.
* Surfactant: Nonion-based surfactant EP7025 manufactured by Nippon Shokubai Co., Ltd.
* Antifungal agent: Lonza pharmaceutical product Proxel GXL
* Defoaming agent: Silicone defoaming agent manufactured by Shin-Etsu Chemical Co., Ltd. KM-72F

The following evaluations were carried out on the manufactured inks.

<Blocking>
Inkjet printing system RICOH Pro VC60000 (manufactured by Ricoh) is filled with the manufactured ink, and roll paper of Lumi Art Gloss 130 gsm (manufactured by Stora Enso, paper width 520.7 mm) is set as a recording medium on both the front and back sides of the media. After performing solid printing at a resolution of 1200 dpi for 3 minutes, it was allowed to stand for 4 hours as it was. A Rewinding module RW6 (manufactured by Hunkeller) was used as the winding device.
After 4 hours, the wound image was taken out and the image was observed and evaluated. The evaluation criteria are as follows.
〔Evaluation criteria〕
◎: Paper does not stick to each other. There is no image peeling, and the image is visually uniform.
○: Paper does not stick to each other. There is no image peeling, but when observed under a microscope, there is a minute image omission of 10 μm or less.
□: Paper does not stick to each other. There is no image peeling, but there is a minute image omission exceeding 10 μm.
Δ: The papers are stuck to each other, and the image is significantly chipped.
×: The papers are stuck together and are united.
In actual use, if it is better than □, there is no problem, and if it is ○ or more, it is more preferable. △ The following are problems in actual use.

<Image bending strength>
Inkjet printing system RICOH Pro VC60000 (manufactured by Ricoh) is filled with the manufactured ink, and as a recording medium, roll paper of Lumi Art Gloss 130 gsm (manufactured by Stora Enso, paper width 520.7 mm) is set, and it is solid at a resolution of 1200 dpi. Printing was performed for 1 minute. A Rewinding module RW6 (manufactured by Hunkeller) was used as the winding device. Immediately after the printing was completed, the image was taken out, folded with the image after 24 hours in an environment of 24 ° C. and 40% RH inside, unfolded again, and then rubbed with an eraser to observe and evaluate the state of the crease. The evaluation criteria are as follows.
〔Evaluation criteria〕
⊚: No white line can be seen.
○: A slight white line is seen in the crease after rubbing with the eraser △: A white line is clearly seen in the crease after rubbing with the eraser ×: A white line is seen in the crease before rubbing with the eraser

The evaluation results are shown in Table 1.

From the results in Table 1, the ink in each example contains an emulsion in which an aqueous medium, a coloring material, an alcohol compound having an alicyclic structure, and a resin are dispersed, and the resin is a polycyclic fat. Since it contains a resin having a ring hydrocarbon group, it can be seen that the blocking and image bending strength were evaluated better than those of the comparative example.

300 Inkjet recording device 301 Recording medium transport unit 203 Recording medium 302 Pretreatment process unit 303 Pretreatment post-processing unit 304 Image formation process unit 304K Recording head 304C Recording head 304M Recording head 304Y Recording head 305 Post-processing process unit 306 Post-processing post-drying unit Part 307 Feeding device 308 Winding device 309 Nozzle surface 310 Printing nozzle 311 Heat roller 312 Heat roller 313 Heat roller 314 Heat roller

Japanese Patent No. 4658203 Japanese Unexamined Patent Publication No. 2011-195648 Japanese Unexamined Patent Publication No. 2011-195685 Japanese Unexamined Patent Publication No. 2011-79991 Japanese Unexamined Patent Publication No. 2011-75753

Claims (11)

Ink applying means for applying ink to a recording medium to form an image, and
A drying means for drying the ink and
In an image forming apparatus having
The ink contains at least an emulsion in which an aqueous medium, a coloring material, an alcohol compound having an alicyclic structure, and a resin are dispersed.
The resin contains a resin having a polycyclic alicyclic hydrocarbon group.
An image forming apparatus , wherein the alcohol compound having an alicyclic structure is cyclohexanedimethanol, and is contained in the ink in an amount of 0.1% by mass or more and 0.5% by mass or less . The image forming apparatus according to claim 1, wherein the polycyclic alicyclic hydrocarbon group is an isobornyl group. The number of carbon atoms constituting the alicyclic in the alcohol compound having an alicyclic structure is one ring of the polycyclic alicyclic hydrocarbon group contained in the resin having the polycyclic alicyclic hydrocarbon group. The image forming apparatus according to claim 1, wherein the number of carbon atoms is the same as that of the constituent carbon atoms. The image forming apparatus according to any one of claims 1 to 3, wherein the polycyclic alicyclic hydrocarbon group is derived from a monomer having a (meth) acryloyl group. The image forming apparatus according to any one of claims 1 to 4, wherein the resin contains an acrylic resin other than the resin having a polycyclic alicyclic hydrocarbon group. The ink application process of applying ink to the recording medium to form an image,
A drying step of drying the ink and
In the image forming method having
The ink contains at least an emulsion in which an aqueous medium, a coloring material, an alcohol compound having an alicyclic structure, and a resin are dispersed.
The resin contains a resin having a polycyclic alicyclic hydrocarbon group.
An image forming method , wherein the alcohol compound having an alicyclic structure is cyclohexanedimethanol, and is contained in the ink in an amount of 0.1% by mass or more and 0.5% by mass or less . It contains at least an emulsion in which an aqueous medium, a coloring material, an alcohol compound having an alicyclic structure, and a resin are dispersed.
The resin contains a resin having a polycyclic alicyclic hydrocarbon group.
The alcohol compound having an alicyclic structure is cyclohexanedimethanol, and the ink is characterized by containing 0.1% by mass or more and 0.5% by mass or less in the ink. The ink according to claim 7, wherein the polycyclic alicyclic hydrocarbon group is an isobornyl group. The number of carbon atoms constituting the alicyclic in the alcohol compound having an alicyclic structure is one ring of the polycyclic alicyclic hydrocarbon group contained in the resin having the polycyclic alicyclic hydrocarbon group. The ink according to claim 7, which has the same number of constituent carbon atoms. The ink according to any one of claims 7 to 9, wherein the polycyclic alicyclic hydrocarbon group is derived from a monomer having a (meth) acryloyl group. The ink according to any one of claims 7 to 10, wherein the resin contains an acrylic resin other than the resin having a polycyclic alicyclic hydrocarbon group.

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