JP7089955B2 - Inkjet ink, inkjet prints and methods for manufacturing inkjet prints - Google Patents

Description

The present invention relates to an inkjet ink, an inkjet print, and a method for manufacturing an inkjet print. More specifically, the present invention relates to an inkjet ink, an inkjet print, and a method for producing an inkjet print, which have excellent ejection stability and can impart various degrees of mattness.

Conventionally, an ink jet printing ink and a printing method for obtaining a printed matter having a matte property have been proposed (Patent Document 1). Patent Document 1 discloses an ink jet printing ink and a printing method that form irregularities by curing an ink containing a photocurable resin to diffusely reflect the surface of a printed matter to exert a matting effect. There is.

Japanese Unexamined Patent Publication No. 2014-101479

The technique described in Patent Document 1 exerts a matting effect by utilizing diffused reflection of unevenness formed on the surface of a printed matter. Therefore, each unevenness needs to be independent. As a result, there is a limit to the matteness that can be obtained, and it may not be possible to express the desired matteness. Further, since it is necessary to form each unevenness independently, the design described in Patent Document 1 tends to limit the designs that can be expressed. Further, in order to form independent unevenness, the one-time ejection amount is likely to be limited, and the inkjet device that can be used at the time of inkjet printing is likely to be limited to the serial type or the like. As a result, the technique described in Patent Document 1 tends to limit the design and productivity of the obtained printed matter.

The present invention has been made in view of such a conventional invention, has excellent ejection stability, can impart various degrees of matte property, and improves the design and productivity of printed matter. It is an object of the present invention to provide a method for producing an inkjet ink, an inkjet print, and an inkjet print to be obtained.

The method for manufacturing an inkjet ink, an inkjet print, and an inkjet print of the present invention that solves the above problems mainly includes the following configurations.

(1) An inkjet ink containing particles having an average particle diameter of 0.4 to 2.5 μm, a refractive index of 1.4 to 1.7, and a specific gravity of 2.1 or less.

According to such a configuration, the inkjet ink contains particles exhibiting the above-mentioned predetermined average particle diameter, refractive index and specific gravity. Such inkjet ink is less likely to cause clogging in nozzles and flow paths during inkjet printing, and has excellent ejection stability. Further, since the inkjet ink contains the above particles, it is possible to impart various degrees of mattness and improve the design of the printed matter. Further, since the inkjet ink exhibits matteness by containing the above particles, it is not essential to form the unevenness independently as in the prior art. As a result, according to the inkjet ink, the inkjet device that can be used at the time of inkjet printing is not limited easily, the amount of one ejection can be increased, and the ink can be applied to the substrate in a short time, so that the printed matter can be printed. It can improve productivity.

(2) The inkjet ink according to (1), wherein the content of the particles is 0.5 to 15% by mass.

According to such a configuration, the inkjet ink has more excellent ejection stability and can easily obtain an excellent matting effect.

(3) The inkjet ink according to (1) or (2), wherein the particles contain spherical crosslinkable polymer fine particles.

According to such a configuration, the inkjet ink is less likely to cause clogging in the nozzle during inkjet printing, and has excellent ejection stability. Further, the spherical crosslinkable polymer fine particles do not easily swell in the ink, and the obtained ink is excellent in stability.

(4) The inkjet ink according to (1) or (2), wherein the particles contain melamine-based beads.

According to such a configuration, the melamine-based beads are less likely to swell in the ink, and the stability of the obtained ink is more excellent.

(5) The inkjet ink according to any one of (1) to (4), wherein the inkjet ink is a radical polymerization type ultraviolet curable ink.

According to such a configuration, the inkjet ink has a large room for material selection and cost merit, and it is easy to design a desired ink.

(6) The inkjet ink according to (5), which comprises (meth) acrylic silane.

With such a configuration, the inkjet ink is more stable.

(7) The particle contains melamine-based beads, and the blending ratio (mass ratio) of the (meth) acrylic silane and the melamine-based beads is 1:10 to 1: 200, according to (6). Inkjet ink.

According to such a configuration, the melamine-based beads are improved in compatibility with, for example, an acrylic monomer by (meth) acrylic silane. As a result, the inkjet ink is more stable.

(8) A method for producing a printed matter, which comprises a step of applying the inkjet ink according to any one of (1) to (4) onto a substrate by an inkjet method, and a step of drying the substrate.

According to such a configuration, by using the above-mentioned inkjet ink, various degrees of matteness can be imparted, and an inkjet printed matter having excellent design can be produced. Further, according to such a method for manufacturing an inkjet print, the inkjet device used is not limited easily, and it is possible to increase the amount of one ejection and apply ink to the substrate in a short time. The productivity of printed matter can be improved.

(9) Includes a step of applying the inkjet ink according to any one of (5) to (7) onto a substrate by an inkjet method, and a step of irradiating the applied inkjet ink with ultraviolet rays to cure the ink. , Manufacturing method of inkjet prints.

According to such a configuration, by using the above-mentioned inkjet ink, various degrees of matteness can be imparted, and an inkjet printed matter having excellent design can be produced. Further, according to such a method for manufacturing an inkjet print, the inkjet device used is not limited easily, and it is possible to increase the amount of one ejection and apply ink to the substrate in a short time. The productivity of printed matter can be improved.

(10) An inkjet printed matter to which the inkjet ink according to any one of (1) to (7) is applied.

According to such a configuration, the obtained printed matter is imparted with various degrees of matte property by using the above-mentioned inkjet ink, and is excellent in designability. In addition, printed matter is easy to be produced efficiently.

According to the present invention, the manufacture of inkjet inks, inkjet prints, and inkjet prints, which have excellent ejection stability, can impart various degrees of matteness, and can improve the design and productivity of printed matter. A method can be provided.

<Inkjet ink>
The inkjet ink of one embodiment of the present invention (hereinafter, also simply referred to as ink) has an average particle diameter of 0.4 to 2.5 μm, a refractive index of 1.4 to 1.7, and a specific gravity of 2. Contains particles that are 1 or less. Since the ink of the present embodiment contains particles showing a predetermined average particle size, refractive index and specific gravity as described above, the nozzle is less likely to be clogged during inkjet printing, and the ejection stability is excellent. Further, since the ink contains the above particles, various degrees of mattness can be imparted, and the design of the printed matter can be improved. Further, since the ink exhibits matteness by containing the above particles, it is not essential to form the unevenness independently as in the prior art. As a result, according to the ink of the present embodiment, the inkjet device that can be used at the time of inkjet printing is not limited easily, and the amount of one ejection can be increased or the ink can be applied onto the substrate in a short time. It can improve the productivity of printed matter. Hereinafter, each configuration will be described.

(particle)
The particles contained in the ink of the present embodiment are characterized by having an average particle diameter of 0.4 to 2.5 μm, a refractive index of 1.4 to 1.7, and a specific gravity of 2.1 or less. do. Ink containing such particles is less likely to clog nozzles and flow paths during inkjet printing, and has excellent ink ejection stability. Further, by imparting such particles, the obtained coating film is less likely to cause white turbidity and the like, and the base material can be imparted with a desired matting property.

The average particle size of the particles may be 0.4 μm or more, preferably 0.8 μm or more. The average particle size of the particles may be 2.5 μm or less, preferably 2.0 μm or less. When the average particle size is less than 0.4 μm, the ink tends to have an insufficient matting effect obtained by applying the particles. On the other hand, when the average particle size exceeds 2.5 μm, the ink may clog the nozzles and flow paths during inkjet printing, and the ejection stability may decrease. In the present embodiment, the average particle size can be measured by, for example, a particle size distribution measuring device based on a laser diffraction / scattering method. An example of the particle size distribution measuring device is a particle size distribution meter (Microtrac UPA manufactured by Nikkiso Co., Ltd.) whose measurement principle is a dynamic light scattering method.

The refractive index of the particles may be 1.40 or more, preferably 1.45 or more. The refractive index of the particles may be 1.70 or less, preferably 1.65 or less. When the refractive index is less than 1.40, the ink tends to have a lower refractive index than the binder resin (for example, an acrylic monomer described later), and it is difficult to obtain a matting effect. On the other hand, when the refractive index exceeds 1.70, the coating film of the obtained printed matter tends to become cloudy. In the present embodiment, the refractive index of the particles can be measured by using, for example, an Abbe refractometer (KPR-30A, manufactured by Shimadzu Corporation) and placing the particles on a prism.

The specific gravity of the particles may be 2.1 or less, preferably 2.0 or less. The lower limit of the specific gravity of the particles is not particularly limited. When the specific gravity of the particles exceeds 2.1, the particles tend to sink during the formation of the coating film, and the desired matting effect tends not to be obtained. In this embodiment, the specific gravity of the particles represents the true specific gravity, and can be measured by using the Gay-Lussac type specific gravity bottle (pycnometer) method.

The content of the particles is not particularly limited. As an example, the content of the particles in the ink is preferably 0.5% by mass or more, more preferably 1% by mass or more, and further preferably 2% by mass or more. The content of the particles in the ink is preferably 15% by mass or less, more preferably 12% by mass or less, and further preferably 10% by mass or less. When the content of the particles is within the above range, the ink tends to obtain a desired matting effect. Further, the ink has excellent storage stability, and the obtained coating film is less likely to cause cloudiness or the like.

The particles of the present embodiment may be any particles exhibiting the above-mentioned predetermined average particle diameter, refractive index and specific gravity, and the material of the particles is not particularly limited. As an example, the particles may be various inorganic particles or organic particles (beads).

The inorganic particles are oxides containing metal elements such as silicon, aluminum, zinc, titanium, zirconium, yttrium, indium, antimony, tin, and tungsten. Among these, the inorganic particles are not much different from the binder resin (for example, acrylic monomer described later) and have a relatively small specific gravity. Therefore, the silica beads (refractive index: 1.44, specific gravity: 2. 0), alumina beads (refractive index: 1.63, specific gravity: 4.0) and the like are preferable. Among these, the inorganic particles are preferably silica beads because the specific gravity is relatively small. Inorganic particles may be used in combination. The composition may not be constant depending on the type of inorganic particles. Therefore, the value of the refractive index is only a general value for the inorganic particles, and the values are slightly different even for the same inorganic particles such as the inorganic particles used in the examples described later. In some cases. The same applies to organic particles.

Organic particles include polymethylmethacrylate beads (refraction rate 1.49, specific gravity: 1.2 to 1.4), acrylic beads (refraction rate 1.50, specific gravity: 1.2 to 1.4), acrylic-styrene. Copolymer beads (refractive index 1.54, specific gravity: 1.2 to 1.25), melamine beads (refractive index 1.57, specific gravity: 1.5 to 1.6), high refractive index melamine beads (refraction rate 1.57, specific gravity: 1.5 to 1.6) Refraction index 1.65, specific gravity: 1.5 to 1.6), polycarbonate beads (refraction index 1.57, specific gravity: 1.4 to 1.5), styrene beads (refraction index 1.60, specific gravity: 1. 05-1.1), crosslinked polystyrene beads (refractive index 1.61, specific gravity: 1.05 to 1.1), polyvinyl chloride beads (refractive index 1.60, specific gravity: 1.35 to 1.5), Benzoguanamine-melamine formaldehyde beads (refractive index 1.68, specific gravity: 1.4 to 1.5), silicone beads (refractive index 1.50, specific gravity: 1.3 to 1.4) and the like. Among these, the organic particles are difficult to swell in the ink and the obtained ink is excellent in stability, so that the crosslinked polymer fine particles such as acrylic beads, melamine beads, and acrylic-styrene copolymer beads are crosslinked. It is more preferable to use spherical crosslinkable polymer fine particles from the viewpoint that the nozzle and the flow path are less likely to be clogged during inkjet printing and the ink ejection stability is improved. In the present embodiment, the true spherical shape means that the bead surface has almost no unevenness or bulge and is a smooth spherical shape. Further, the organic particles are preferably melamine beads because they are particularly difficult to swell in the ink and the stability of the obtained ink is particularly excellent. The organic particles may be used in combination, or may be composite fine particles in which the surface of the organic particles is coated with the inorganic particles.

(Other ingredients)
The ink of the present embodiment may contain the above particles, and other components are not particularly limited. The ink may contain, for example, a binder resin, a dispersant, a solvent and various optional components.

(Binder resin)
The binder resin is contained, for example, for adjusting the viscosity of the ink, adjusting the hardness of the obtained printed matter, and controlling the shape.

The type of binder resin is not particularly limited. As an example, the binder resin includes epoxy resin, diallyl phthalate resin, silicone resin, phenol resin, unsaturated polyester resin, polyimide resin, polyurethane resin, melamine resin, urea resin, ionomer resin, ethylene ethyl acrylate resin, and acrylonitrile acrylate styrene. Copolymer resin, acrylonitrile styrene resin, acrylonitrile chloride polyethylene styrene copolymer resin, ethylene vinegar resin, ethylene vinyl alcohol copolymer resin, acrylonitrile butadiene styrene copolymer resin, vinyl chloride resin, chlorinated polyethylene resin, polyvinylidene chloride resin, acetic acid Cellulose resin, fluororesin, polyoxymethylene resin, polyamide resin, polyarylate resin, thermoplastic polyurethane elastomer, polyether ether ketone resin, polyether sulfone resin, polyethylene, polypropylene, polycarbonate resin, polystyrene, polystyrene maleic acid copolymer resin, Polystyrene acrylic acid copolymer resin, polyphenylene ether resin, polyphenylene sulfide resin, polybutadiene resin, polybutylene terephthalate resin, acrylic resin, methacrylic resin, methylpentene resin, polylactic acid, polybutylene succinate resin, butyral resin, formal resin, polyvinyl alcohol , Polyvinylpyrrolidone, ethyl cellulose, carboxymethyl cellulose, gelatin, and copolymer resins thereof and the like are exemplified. The binder resin can be appropriately selected in consideration of film strength, viscosity, residual viscosity of inkjet ink, dispersion stability of pigment, thermal stability, non-coloring property, water resistance, and chemical resistance. The binder resin may be used in combination.

-Fluororesin Fluororesin is not particularly limited. As an example, the fluororesin is preferably a copolymer of various fluorine-containing monomers and a vinyl monomer. Further, the fluororesin is more preferably a copolymer with a vinyl ether monomer among the vinyl monomers. Further, the fluororesin is more preferably a copolymer of fluoroethylene and a vinyl ether monomer.

The weight average molecular weight (Mw) of the fluororesin is not particularly limited. As an example, Mw is preferably 5000 or more, and more preferably 8000 or more. Mw is preferably 50,000 or less, and more preferably 40,000 or less. When Mw is within the above range, the fluororesin is easily dissolved in the solvent. In addition, the obtained ink has improved drying properties and is excellent in ejection stability during inkjet printing. When Mw is less than 5000, the obtained printed matter tends to be sticky and the blocking prevention property tends to be lowered. On the other hand, when Mw exceeds 50,000, the solubility of the fluororesin tends to decrease, and the ejection stability of the ink during inkjet printing tends to decrease. In the present specification, Mw and the number average molecular weight (Mn) described later are values measured by, for example, GPC (gel permeation chromatography), and are high-speed GPC devices (manufactured by Tosoh Corporation, HLC-8120GPC). Can be measured using.

-Acrylic resin Acrylic resin is not particularly limited. As an example, the acrylic resin is exemplified by a polymer of acrylic acid ester (acrylate) or methacrylic acid ester (methacrylate). More specifically, the acrylic resin is an acrylic acid alkyl ester such as methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate; methyl methacrylate, methacrylic. Alkyl methacrylate esters such as ethyl methacrylate, propyl methacrylate, butyl methacrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate; 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate and the like. Hydroxy group-containing acrylic acid esters; Polymers such as hydroxy group-containing methacrylic acid esters such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and 4-hydroxybutyl methacrylate are exemplified. These may be used together.

The weight average molecular weight (Mw) of the acrylic resin is not particularly limited. As an example, Mw is preferably 5000 or more, and more preferably 10,000 or more. Mw is preferably 100,000 or less, and more preferably 50,000 or less. When Mw is within the above range, the ink containing such an acrylic resin has excellent ejection stability at the time of inkjet printing.

-Vinyl chloride resin The vinyl chloride resin is not particularly limited. As an example, examples of the vinyl chloride resin include a copolymer of vinyl chloride with other monomers such as vinyl acetate, vinylidene chloride, acrylic acid, maleic acid, and vinyl alcohol. Among these, the vinyl chloride resin is preferably a copolymer (vinyl chloride vinegar copolymer) containing a structural unit derived from vinyl chloride and vinyl acetate.

The vinyl chloride vinyl acetate copolymer can be obtained, for example, by suspension polymerization. The vinyl chloride vinyl acetate copolymer preferably contains 70 to 90% by mass of vinyl chloride units. Within the above range, the vinyl chloride vinyl acetate copolymer is excellent in long-term storage stability because it is stably dissolved in the ink. In addition, the obtained ink has excellent ejection stability.

In addition to the vinyl chloride unit and the vinyl acetate unit, the vinyl chloride vinegar copolymer may include other structural units, if necessary. As an example, other structural units include a carboxylic acid unit, a vinyl alcohol unit, a hydroxyalkyl acrylate unit, and the like. Among these, the other structural unit is preferably a vinyl alcohol unit.

The number average molecular weight (Mn) of the vinyl chloride resin is not particularly limited. As an example, the Mn of the vinyl chloride resin is preferably 10,000 or more, and more preferably 12,000 or more. Further, Mn is preferably 50,000 or less, and more preferably 42,000 or less. Mn can be measured by GPC and can be obtained as a relative value in terms of polystyrene.

-Silicone resin The silicone resin is not particularly limited. As an example, the silicone resin includes methyl-based straight silicone resin (polydimethylsiloxane), methylphenyl-based straight silicone resin (polydimethylsiloxane in which a part of the methyl group is replaced with a phenyl group), acrylic resin-modified silicone resin, and polyester. Examples thereof include resin-modified silicone resin, epoxy resin-modified silicone resin, alkyd resin-modified silicone resin, and rubber-based silicone resin. These may be used together. Among these, as the silicone resin, a methyl-based straight silicone resin, a methylphenyl-based straight silicone resin, and an acrylic resin-modified silicone resin are preferable.

The silicone resin may be dissolved in an organic solvent or the like. Examples of the organic solvent include xylene and toluene.

The number average molecular weight (Mn) of the silicone resin is not particularly limited. As an example, the Mn of the silicone resin is preferably 10,000 or more, and more preferably 20,000 or more. Further, Mn is preferably 5000000 or less, and more preferably 3000000 or less. Mn can be measured by GPC and can be obtained as a relative value in terms of polystyrene.

Returning to the description of the binder resin as a whole, the content of the binder resin is not particularly limited. As an example, the binder resin is preferably 1% by mass or more, more preferably 3% by mass or more, and 5% by mass or more in the ink constituting the ink set in terms of solid content. Is more preferable. The binder resin is preferably 40% by mass or less, more preferably 30% by mass or less, and further preferably 25% by mass or less in the ink. When the content of the binder resin is less than 1% by mass, it is difficult to obtain the desired performance as a binder, and the adhesion to the substrate tends to decrease. On the other hand, when the content of the binder resin exceeds 40% by mass, the viscosity of the ink tends to increase, and the ejection stability during inkjet printing tends to decrease.

(Dispersant)
Dispersants are included to disperse the pigment. The dispersant is not particularly limited. Examples of the dispersant include anionic surfactants, nonionic surfactants, polymer dispersants and the like. These may be used together.

Anionic surfactants include fatty acid salts, alkyl sulfate ester salts, alkylbenzene sulfonates, alkylnaphthalene sulfonates, lignin sulfonates, dialkyl sulfosuccinates, alkyl phosphate ester salts, naphthalene sulfonate formalin condensates, poly. Examples thereof include oxyethylene alkyl sulfate ester salts and their substituted derivatives.

Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, and oxyethylene oxy. Examples thereof include propylene block polymers and their substituted derivatives.

The polymer dispersant having both an acid value and a base value and having an acid value larger than the base value is preferable from the viewpoint of obtaining more stable dispersion characteristics. For example, the polymer dispersants are PB series manufactured by Ajinomoto Fine-Techno Co., Ltd., Hinoact series manufactured by Kawaken Fine Chemical Co., Ltd., Solspers series manufactured by Japan Lubrizol Co., Ltd., and Kusumoto Kasei Co., Ltd. ), The Efka (registered trademark) series manufactured by BASF Japan Ltd., and the like are exemplified.

The content of the dispersant is appropriately determined depending on the type and content of the pigment to be dispersed. As an example, the content of the dispersant is preferably 5 parts by mass or more, and more preferably 10 parts by mass or more with respect to 100 parts by mass of the pigment. The content of the dispersant is preferably 150 parts by mass or less, and more preferably 80 parts by mass or less with respect to 100 parts by mass of the pigment. When the content of the dispersant is less than 5 parts by mass, the pigment tends to be difficult to disperse. On the other hand, when the content of the dispersant exceeds 150 parts by mass, the raw material cost tends to increase and the dispersion of the pigment tends to be hindered.

(solvent)
The solvent is a liquid component for dissolving the binder resin in the ink constituting the ink set. The type of solvent is not particularly limited. For example, the solvent is water, a glycol ether solvent, an acetate solvent, an alcohol solvent, a ketone solvent, an ester solvent, a hydrocarbon solvent, a fatty acid ester solvent, an aromatic solvent and the like. These may be used together. Among these, the solvent of the present embodiment preferably contains at least one of a glycol ether solvent and an acetate solvent. Both the glycol ether solvent and the acetate solvent have a low viscosity and a relatively high boiling point. Therefore, the ink containing these as a solvent has more improved drying property and more excellent ejection stability at the time of inkjet printing.

Glycol ether-based solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono (iso) propyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, propylene glycol monomethyl ether, and propylene glycol. Monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol mono-n-propyl ether, dipropylene glycol mono-n -Butyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol mono-n-propyl ether, triethylene glycol mono-n-butyl ether, tripropylene glycol monoethyl ether, tripropylene glycol mono-n-propyl Ether, tripropylene glycol mono-n-butyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, polyethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol ethyl methyl ether, diethylene glycol isopropyl methyl ether, diethylene glycol butyl methyl ether , Triethylene glycol butyl methyl ether, dipropylene glycol dimethyl ether, tripropylene glycol dimethyl ether and the like are exemplified.

As the acetate-based solvent, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monoisopropyl ether acetate, ethylene glycol mono-n-butyl ether acetate, ethylene glycol mono-sec-butyl ether acetate, Ethylene glycol monoisobutyl ether acetate, ethylene glycol mono-tert-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monoisopropyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol mono-n-butyl ether Acetate, Propylene Glycol Mono-sec-Butyl Ether Acetate, Propylene Glycol Monoisobutyl Ether Acetate, Propylene Glycol Mono-tert-Butyl Ether Acetate, 3-Methyl-3-methoxybutyl Acetate, 3-Methyl-3-ethoxybutyl Acetate, 3-Methyl -3-Propylene butyl acetate, 3-Methyl-3-isopropoxybutyl acetate, 3-Methyl-3-n-Butoxyethyl acetate, 3-Methyl-3-Isobutoxycybutyl acetate, 3-Methyl-3-sec- Alkylene glycol monoalkyl ether acetates such as butoxysibutyl acetate, 3-methyl-3-tert-butoxysibutyl acetate, ethylene glycol diacetate, diethylene glycol diacetate, triethylene glycol diacetate, propylene glycol diacetate, dipropylene glycol Examples thereof include diacetate and tripropylene glycol diacetate.

The solvent of the present embodiment preferably has a boiling point of 150 ° C. or higher, more preferably 180 ° C. or higher. Further, the solvent preferably has a boiling point of 300 ° C. or lower, more preferably 280 ° C. or lower. When the boiling point is within the above range, the obtained ink has more improved drying property and more excellent ejection stability at the time of inkjet printing. Further, according to the ink, a clear printed matter with less bleeding is likely to be formed. When the boiling point of the solvent is less than 150 ° C., the ink tends to dry in the vicinity of the head nozzle, and the ejection stability tends to decrease. On the other hand, when the boiling point of the solvent exceeds 300 ° C., the ink is difficult to dry, and the drying step at the time of forming the printed matter tends to take time. In addition, the image of the obtained printed matter tends to be blurred.

The content of the solvent is not particularly limited. As an example, the solvent is preferably 50% by mass or more, and more preferably 60% by mass or more in the ink constituting the ink set. The solvent is preferably 99% by mass or less, more preferably 80% by mass or less in the ink. When the content of the solvent is less than 50% by mass, the viscosity of the ink tends to be high, and the ejection stability at the time of inkjet printing tends to be lowered. On the other hand, when the content of the solvent exceeds 99% by mass, the proportion of the binder resin that can be added to the ink becomes low, and it tends to be difficult to obtain the desired performance.

(Optional ingredient)
The ink constituting the ink set of the present embodiment may contain an arbitrary component as appropriate in addition to the above-mentioned components. Examples of optional components include heat stabilizers, antioxidants, preservatives, defoamers, penetrants, antioxidants, leveling agents, pH regulators, polymerization inhibitors, ultraviolet absorbers, light stabilizers and the like.

Further, the type of ink of the present embodiment may be a radical polymerization type ultraviolet curable ink or a cationic polymerization type ultraviolet curable ink. In these cases, in addition to the above components, the following components may be further contained.

-Radical Polymerization Type UV Curable Ink In the case of a radical polymerization type ink, the ink mainly contains a reactive monomer, a reactive oligomer, and a photopolymerization initiator in addition to the above particles. Since the ink is a radical polymerization type, the ink is cheaper than the cationic polymerization type, and many materials are on the market, so that the ink design is easy.

The reactive monomer is not particularly limited. As an example, the reactive monomer is various aromatic vinyl-based monomers, vinyl ester monomers, vinyl ethers, allyl compounds, (meth) acrylamides, (meth) acrylates and the like. More specifically, the reactive monomer is an aromatic vinyl-based monomer such as styrene, α-methylstyrene, α-chlorostyrene, vinyltoluene, divinylbenzene; vinyl acetate, vinyl butyrate, N-vinylformamide, N-. Vinyl ester monomers such as vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, divinyl adipate; vinyl ethers such as ethyl vinyl ether and phenylvinyl ether; diallyl phthalate, trimethylolpropanediallyl ether, allyl glycidyl ether and the like. Allyl compounds; acrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylate, N-methylolacrylamide, N-methoxymethylacrylamide, N-butoxymethylacrylamide, Nt-butylacrylamide, acrylic morpholine, methylenebis (Meta) acrylamides such as acrylamide; (meth) acrylic acid, methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, -n-butyl (meth) acrylic acid, (meth) acrylic Acid-i-butyl, (meth) acrylate-t-butyl, (meth) hexyl acrylate, (meth) -2-ethylhexyl acrylate, (meth) lauryl acrylate, stearyl (meth) acrylate, (meth) Tetrahydrofurfuryl acrylate, (meth) morpholyl acrylate, (meth) -2-hydroxyethyl acrylate, (meth) -2-hydroxypropyl acrylate, (meth) -4-hydroxybutyl acrylate, (meth) acrylic Glycidyl acid, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate , (Meta) dicyclopentenyl acrylate, (meth) dicyclopentenyloxyethyl acrylate, (meth) dicyclopentanyl acrylate, allyl (meth) acrylate, -2-ethoxyethyl (meth) acrylate, ( Monofunctional (meth) acrylates such as isobornyl acrylate, acrylic acid = (2-ethyl-2-methyl-1,3-dioxolan-4-yl) methyl, tetrahydrofurfuryl acrylate, phenyl (meth) acrylate. ; And di (meth) ethylene glycol acrylate, di (meth) Diethylene glycol acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate (n = 5-14), propylene glycol di (meth) acrylate, di Dipropylene glycol (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate (n = 5-14), di (meth) acrylic Acid-1,3-butylene glycol, di (meth) acrylic acid-1,4-butanediol, di (meth) acrylic acid polybutylene glycol (n = 3-16), di (meth) acrylic acid poly (1-) Methylbutylene glycol) (n = 5-20), di (meth) acrylate-1,6-hexanediol, di (meth) acrylate-1,9-nonanediol, di (meth) acrylate neopentyl glycol, Neopentyl glycol di (meth) acrylic acid ester of hydroxypivalate, dicyclopentanediol di (meth) acrylic acid, tricyclodecane di (meth) acrylic acid, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) Acrylate, Pentaerythritol Tetra (meth) Acrylate, Ditrimethylol Propane Tetra (Meta) Acrylate, Dipenta Erythritol Tetra (Meta) Acrylate, Dipenta Erythritol Penta (Meta) Acrylate, Dipenta Erythritol Hexa (Meta) Acrylate, Trimethylol Propanetri Oxyethyl (meth) acrylate, trimethylolpropane trioxypropyl (meth) acrylate, trimethylolpropanepolyoxyethyl (meth) acrylate, trimethylolpropanepolyoxypropyl (meth) acrylate, tris (2-hydroxyethyl) isocyanuratetri (Meta) acrylate, Tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added virphenol F di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate Meta) acrylate, bisphenol F di (meth) acrylate with propylene oxide, tricyclodecanedimethanol di (meth) acrylate, bisphenol A Polyfunctional (meth) acrylates such as poxydi (meth) acrylate and bisphenol F epoxy di (meth) acrylate. These reactive monomers may be used in combination. Among these, the reactive monomer is preferably acrylic acid = (2-ethyl-2-methyl-1,3-dioxolane-4-yl) methyl or tetrahydrofurfuryl acrylate because it has a relatively low viscosity.

The content of the reactive monomer is not particularly limited. As an example, the content of the reactive monomer is preferably 50% by mass or more, and more preferably 70% by mass or more in the ink. The content of the reactive monomer in the ink is preferably 95% by mass or less, more preferably 90% by mass or less. When the content of the reactive monomer is within the above range, the ink tends to exhibit appropriate curability. In addition, the ink is easily adjusted to an appropriate viscosity and has excellent ejection stability during inkjet printing.

The reactive oligomer is not particularly limited. As an example, the reactive oligomer is urethane acrylate, polyester acrylate, epoxy acrylate, silicon acrylate, polybutadiene acrylate and the like. Among these, the reactive oligomer is preferably urethane acrylate, and more preferably an aliphatic urethane acrylate, from the viewpoint of excellent toughness, adhesiveness and flexibility. These reactive oligomers may be used in combination.

The content of the reactive oligomer is not particularly limited. As an example, the content of the reactive oligomer is preferably 2% by mass or more, and more preferably 5% by mass or more in the ink. The content of the reactive oligomer is preferably 40% by mass or less, and more preferably 30% by mass or less in the ink. When the content of the reactive oligomer is within the above range, the toughness, adhesiveness, and flexibility of the obtained coating film can be easily adjusted appropriately. In addition, the ink is easily adjusted to an appropriate viscosity and has excellent ejection stability during inkjet printing.

The photopolymerization initiator is not particularly limited. As an example, the photopolymerization initiator is benzoins, benzyl ketals, amino ketones, titanosen, bisimidazoles, hydroxy ketones, acylphosphine oxides and the like. The photopolymerization initiator may be used in combination. Among these, the photopolymerization initiator is preferably hydroxyketones or acylphosphine oxides from the viewpoint of high reactivity and refractory yellowing.

The content of the photopolymerization initiator is not particularly limited. As an example, the content of the photopolymerization initiator is preferably 1% by mass or more, and more preferably 2% by mass or more in the ink. The content of the photopolymerization initiator in the ink is preferably 15% by mass or less, more preferably 12% by mass or less. When the content of the photopolymerization initiator is within the above range, the ink is likely to be cured at an appropriate curing rate and curing rate.

Radical polymerization type inks can be used as dispersion aids, sensitizers, heat stabilizers, antioxidants, preservatives, defoaming agents, resin binders, resin emulsions, antioxidants, leveling agents, and pH adjustments, if necessary. Agents, pigment derivatives, polymerization inhibitors, ultraviolet absorbers, light stabilizers and the like may be blended. In particular, the ink of the present embodiment preferably contains (meth) acrylic silane as a dispersion aid.

The (meth) acrylic silane is not particularly limited as long as it is a compound having a (meth) acrylic group ((meth) acryloyl group or (meth) acryloyloxy group) and a hydrolyzable silyl group. The (meth) acrylic group and the hydrolyzable silyl group can be bonded via an organic group. The (meth) acrylic group can be bonded to an organic group via an oxygen atom. In this case, the (meth) acrylic group becomes a (meth) acryloyl group. The organic group may be an aliphatic hydrocarbon group (the aliphatic hydrocarbon group may be chain-like, branched, cyclic, or a combination thereof), an aromatic hydrocarbon group, or a combination thereof. The organic group may have a heteroatom such as an oxygen atom, a nitrogen atom and a sulfur atom. The hydrolyzable silyl group is a methyldimethoxysilyl group, a methyldiethoxysilyl group, a trimethoxysilyl group, a triethoxysilyl group and the like.

(Meta) Acrylicsilane is 3-methacryloxypropylmethyldimethoxylane, 3-methacryloxypropyltrimethoxylane, 3-methacryloxypropylmethyldiethoxylan, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltri. Such as methoxyrun.

The (meth) acrylic silane can react with the hydroxyl group partially remaining in the particles (for example, melamine-based beads) in the ink. The particles after the reaction have excellent compatibility with the above-mentioned reactive monomer. Therefore, since the ink of the present embodiment contains (meth) acrylic silane, the reaggregation of particles in the ink can be reduced, so that the storage stability of the ink is more likely to be improved.

The content of (meth) acrylic silane is not particularly limited. As an example, the content of (meth) acrylic silane is preferably 0.01% by mass or more, and more preferably 0.02% by mass or more in the ink. The content of (meth) acrylic silane is preferably 5% by mass or less, and more preferably 1% by mass or less in the ink. When the content of the (meth) acrylic silane is within the above range, the ink tends to improve the compatibility of the particles and the storage stability. (Meta) acrylic silanes are particularly useful when melamine-based beads are included as particles. That is, the melamine-based beads have improved compatibility with, for example, an acrylic monomer by using (meth) acrylic silane. As a result, the ink has better storage stability.

The blending ratio (mass ratio) of the (meth) acrylic silane and the melamine-based beads is preferably 1:10 to 1:200, more preferably 1:20 to 1:200, and 1:50. It is more preferably ~ 1: 200. When the blending ratio is within the above range, the compatibility of the melamine-based beads with (meth) acrylic silane, for example, with an acrylic monomer is further improved. As a result, the ink has even better storage stability.

-Cationic polymerization type ultraviolet curable inkjet ink In the case of a cationic polymerization type ink, the ink mainly contains a dispersant, a cationically polymerizable compound, and a photopolymerization initiator in addition to the above particles.

The cationically polymerizable compound is not particularly limited. As an example, the cationically polymerizable compound is an aromatic epoxide, an alicyclic epoxide, an aliphatic epoxide or the like. The aromatic epoxide is di or polyglycidyl ether of bisphenol A or its alkylene oxide adduct, di or polyglycidyl ether of hydrogenated bisphenol A or its alkylene oxide adduct, novolak type epoxy resin and the like. The alicyclic epoxide is a cyclohexene oxide or a cyclopentene oxide obtained by epoxidizing a compound having a cycloalkane ring such as at least one cyclohexene or cyclopentene ring with an oxidizing agent such as hydrogen peroxide or a peracid. Contains compounds and the like. The aliphatic epoxide is a diglycidyl ether of an alkylene glycol such as a diglycidyl ether of ethylene glycol, a diglycidyl ether of propylene glycol or a diglycidyl ether of 1,6-hexanediol, or di or triglycidyl of glycerin or an alkylene oxide adduct thereof. Polyglycidyl ether of polyhydric alcohol such as ether, diglycidyl ether of polyethylene glycol or its alkylene oxide adduct, diglycidyl ether of polyalkylene glycol such as diglycidyl ether of polypropylene glycol or its alkylene oxide adduct.

The content of the cationically polymerizable compound is not particularly limited. As an example, the content of the cationically polymerizable compound is preferably 50% by mass or more, and more preferably 70% by mass or more in the ink. The content of the cationically polymerizable compound is preferably 95% by mass or less, more preferably 90% by mass or less in the ink. When the content of the cationically polymerizable compound is within the above range, the ink has excellent curability of the obtained coating film.

The photopolymerization initiator is not particularly limited. For example, the photopolymerization initiators are acetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophen, p-dimethylaminopropiophenone, benzophenone, 2-chlorobenzophenone, pp'-dichlorobenzophen, pp'-bisdiethylaminobenzophenone, Michler ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin isobutyl ether, benzoin n-butyl ether, benzyl dimethyl ketal, tetramethylthium monosulfide, Thioxanson, 2-chlorothioxanson, 2-methylthioxanson, azobisisobutyronitrile, benzoin peroxide, di-tert-butyl peroxide, 1-hydroxycyclohexylphenylketone, 2-hydroxy-2-methyl-1 -Phenyl-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-1-one, methylbenzoylformate and the like.

The content of the photopolymerization initiator is not particularly limited. As an example, the content of the photopolymerization initiator is preferably 1% by mass or more, and more preferably 2% by mass or more in the ink. The content of the photopolymerization initiator in the ink is preferably 15% by mass or less, more preferably 12% by mass or less. When the content of the photopolymerization initiator is within the above range, the ink has excellent curability of the obtained coating film.

Returning to the description of the entire ink, the viscosity of the ink is not particularly limited. As an example, the viscosity of the ink is preferably 2 mPa · s or more, and more preferably 5 mPa · s or more. The viscosity is preferably 50 mPa · s or less, and more preferably 30 mPa · s or less. When the viscosity is within the above range, the ink is less likely to cause ejection defects from the inkjet head, and the ejection stability is excellent. In the present embodiment, the viscosity of the ink can be measured using a B-type viscometer (TVB-20LT manufactured by Toki Sangyo Co., Ltd., rotor rotation speed 60 rpm).

The method for adjusting the viscosity within the above range is not particularly limited. As an example, the viscosity can be adjusted by the amount of each component added, the type of solvent and the amount of addition. As for the viscosity, a viscosity modifier such as a thickener may be used if necessary.

The surface tension of the ink is not particularly limited. The surface tension of the ink is preferably 20 dyne / cm or more, and more preferably 22 dyne / cm or more at 25 ° C. Further, the surface tension of the ink is preferably 40 dyne / cm or less, and more preferably 35 dyne / cm or less at 25 ° C. When the surface tension is within the above range, the ink has excellent ejection stability. In the present embodiment, the surface tension can be measured using a static surface tensiometer (plate method) (CBVP-A3 manufactured by Kyowa Interface Science Co., Ltd.).

The ink of the present embodiment can form an ink image on the base material by ejecting the ink to the base material using an inkjet device that employs an inkjet method. Since the printed matter on which the ink image is formed contains the above particles, it is possible to impart various degrees of mattness to the base material, and it is possible to improve the design of the printed matter. Further, since the ink exhibits matteness by containing the above particles, it is not essential to form the unevenness independently as in the prior art. As a result, according to the ink, the inkjet device that can be used at the time of inkjet printing is not limited easily, the amount of one ejection can be increased, and the ink can be applied to the substrate in a short time, so that the production of printed matter can be produced. It can improve sex.

<Manufacturing method of printed matter (for other than UV curable inkjet ink)>
The method for producing a printed matter according to an embodiment of the present invention mainly includes a step of applying the ink onto the substrate by an inkjet method and a step of drying the substrate using the above-mentioned ink. As a result of drying, a printed matter on which an image is formed is produced.

(Granting process)
The method of applying the ink constituting the ink set to the base material by the inkjet recording method is not particularly limited. Such methods include a charge modulation method, a microdot method, a charge injection control method, a continuous method such as an ink mist method, a piezo method, a pulse jet method, a bubble jet (registered trademark) method, an electrostatic suction method, and the like. An example is a demand method.

The inkjet device for applying ink supplies ink from the ink tank to the pressure chamber via the ink supply path, applies an electric signal corresponding to the image data to the piezoelectric element, and drives the piezoelectric element to drive the pressure. It is a device that deforms the vibrating plate that constitutes a part of the chamber to reduce the volume of the pressure chamber, and ejects the ink in the pressure chamber as droplets from the ejection port of the nozzle (head).

There are two types of heads: shuttle method (multipath method) and line method (single pass method). The multipath method is a method in which a short serial head is used and recording is performed while scanning the head in the width direction of the base material. On the other hand, the single-pass method uses a full-line head that covers the entire area of the base material, and moves the full-line head and the base material only once relatively to form an image on the entire surface of the base material. Is.

The printed matter manufacturing method of the present embodiment is particularly effective when the printed matter is manufactured by using an inkjet device that employs a single-pass method. That is, when the unevenness is made independent and the matte property is exhibited as in the conventional technique, it is difficult to adopt the single pass method in which the unevenness easily overlaps. However, as described above, the ink used in the present embodiment exhibits a matte property because it contains particles. Therefore, in the method for manufacturing a printed matter of the present embodiment, it is not essential to form the unevenness independently as in the prior art. As a result, the inkjet device that can be used at the time of inkjet printing is not limited easily, and a single pass method can also be adopted. As a result, the method for producing a printed matter of the present embodiment can increase the amount of one ejection and can apply ink to the substrate in a short time, and can improve the productivity of the printed matter.

The base material to which the ink is applied is not particularly limited. As an example, the base material is a metal plate such as steel plate, aluminum or stainless steel, a plastic plate or film such as acrylic, polycarbonate, ABS, polypropylene, polyester or vinyl chloride, a ceramic plate, concrete, wood, glass or the like. These substrates are preferably treated with a pretreatment agent prior to printing. Examples of the pretreatment agent include fluorine-based paints, silicone-based paints, acrylic silicone-based paints, acrylic paints, epoxy-based paints, urethane-based paints, and the like. Examples of the method of applying these pretreatment agents to the substrate include a spray method, a roll coater method, a curtain flow coater method, a brush coating method, a spatula coating method, a dipping method, and an inkjet method. The base material includes cationic dyeable polyester (CDP) fiber, polyethylene terephthalate (PET) fiber, polybutylene terephthalate (PBT) fiber, polytrimethylene terephthalate (PTT) fiber, total aromatic polyester fiber, polylactic acid fiber and the like. It may be a polyester fiber, an acetate fiber, a triacetate fiber, a polyurethane fiber, a nylon fiber or the like, or a cloth made of a composite fiber thereof or the like. These can be appropriately selected according to the application. When the substrate is a fabric, the fabric is preferably treated with a pretreatment agent prior to printing. Pretreatment agents include water-soluble polymers, water-insoluble inert organic compounds, flame retardants, UV absorbers, reduction inhibitors, antioxidants, pH regulators, hydrotropes, defoamers, penetrants, and microporous formation. Examples include agents. Examples of the method of applying these pretreatment agents to the fabric include a pad method, a spray method, a dipping method, a coating method, a laminating method, a gravure method, and an inkjet method.

(Drying process)
The inked substrate is then dried. The drying conditions are not particularly limited. As an example, the drying temperature is preferably 150 ° C. or higher, more preferably 180 ° C. or higher, and even more preferably 200 ° C. or higher. The drying temperature is preferably 400 ° C. or lower, more preferably 350 ° C. or lower, and even more preferably 300 ° C. or lower. The drying time is preferably 1 minute or longer, more preferably 2 minutes or longer, and even more preferably 3 minutes or longer. The drying time is preferably 60 minutes or less, more preferably 30 minutes or less, and even more preferably 10 minutes or less. By such drying, the pigment in the ink is less likely to cause discoloration and the like, and the solvent can be removed. The drying is preferably performed at the same time or immediately after the ink is applied to the substrate in order to prevent the ink from bleeding.

The obtained printed matter is a printed matter in which a base material and a printing layer formed on the base material are formed. The printed layer contains the above-mentioned particles and is imparted with a matte property. Therefore, in the method for manufacturing a printed matter of the present embodiment, it is not essential to form the unevenness independently as in the prior art. As a result, the inkjet device that can be used at the time of inkjet printing is not limited easily, and a single pass method can also be adopted. As a result, the method for producing a printed matter of the present embodiment can increase the amount of one ejection and can apply ink to the substrate in a short time, and can improve the productivity of the printed matter.

<Manufacturing method of printed matter (in the case of UV curable inkjet ink)>
The method for producing an inkjet print according to an embodiment of the present invention (hereinafter, also simply referred to as a method for producing a print) is based on an inkjet method, particularly when the above-mentioned ultraviolet curable ink is used to produce an inkjet print. It includes a step of applying the ink on the substrate and a step of irradiating the applied ink with ultraviolet rays to cure the ink. Each will be described below.

(Granting process)
The applying step is a step of applying the above-mentioned ink onto the base material by an inkjet method. The base material is not particularly limited. The base material may be the same as that described above.

A chemical conversion treatment film, an undercoat film, or the like may be formed on the surface of the base material. The chemical conversion treatment film is formed on the entire surface of the base material, and can improve the adhesion and corrosion resistance of the coating film. The undercoat coating film is formed on the surface of the base material or the chemical conversion treatment film, and can improve the coating film adhesion and corrosion resistance. The resin contained in the undercoat paint for forming the undercoat coating film is not particularly limited. As an example, the resin is a polyester resin, an epoxy resin, an acrylic resin, or the like.

As the inkjet device for applying ink, the same one as described above may be used. Further, the method for manufacturing a printed matter of the present embodiment is particularly effective when the printed matter is manufactured by using an inkjet device adopting a single-pass method. That is, as described above, the ink used in the present embodiment exhibits matteness by containing particles. Therefore, in the method for manufacturing a printed matter of the present embodiment, the inkjet device that can be used at the time of inkjet printing is not limited easily, and a single pass method can also be adopted. As a result, the method for producing a printed matter of the present embodiment can increase the amount of one ejection and can apply ink to the substrate in a short time, and can improve the productivity of the printed matter.

(Curing process)
The curing step is a step of irradiating the applied ink with ultraviolet rays to cure the ink. The ink ejected onto the substrate is irradiated with ultraviolet rays by an ultraviolet irradiation lamp attached to the inkjet device and cured. Examples of the ultraviolet irradiation lamp include a mercury lamp, a gas / solid-state laser, and the like. Among these, the ultraviolet irradiation lamp is preferably a mercury lamp or a metal halide lamp. In addition, the ultraviolet irradiation lamp may be an ultraviolet light emitting diode (UV-LED) or an ultraviolet laser diode (UV-LD).

The integrated amount of ultraviolet rays during curing is not particularly limited. The integrated light amount is preferably 40 mJ / cm ² or more, and more preferably 60 mJ / cm ² or more. The integrated light intensity is preferably 500 mJ / cm ² or less, and more preferably 400 mJ / cm ² or less. The integrated light amount can be measured using, for example, an ultraviolet illuminance meter / photometer (UV-351-25, manufactured by Oak Mfg. Co., Ltd.) under the conditions of a measurement wavelength range of 240 to 275 nm and a measurement wavelength center of 254 nm.

As described above, according to the method for producing a printed matter of the present embodiment, by using the above ink, various degrees of matte property can be imparted, and an inkjet printed matter having excellent design can be produced. Further, according to such a method for manufacturing an inkjet print, the inkjet device used is not limited easily, and it is possible to increase the amount of one ejection and apply ink to the substrate in a short time. The productivity of printed matter can be improved.

Hereinafter, the present invention will be described in more detail with reference to Examples. The present invention is not limited to these examples.

The raw materials used are shown below.
(particle)
Particle 1: Silica beads, SS-50F, manufactured by Tosoh Silica Co., Ltd., average particle diameter 1.3 μm, refractive index 1.46, specific gravity 2.0
Particle 2: Acrylic beads, J-4PY, manufactured by Negami Kogyo Co., Ltd., average particle diameter 2.2 μm, refractive index 1.5, specific gravity 1.45
Particle 3: Melamine beads, Epostal S12, manufactured by Nippon Shokubai Co., Ltd., average particle diameter 1.2 μm, refractive index 1.65, specific gravity 1.5
Particle 4: Alumina beads, Arna beads CB-P02, manufactured by Showa Denko KK, average particle diameter 2.0 μm, refractive index 1.7, specific gravity 3.78
Particle 5: Acrylic beads, J-4PY, manufactured by Negami Kogyo Co., Ltd., average particle diameter 3.3 μm, refractive index 1.5, specific gravity 1.45
Particle 6: Titanium oxide, R-38L, manufactured by Sakai Chemical Industry Co., Ltd., average particle diameter 0.4 μm, refractive index 2.72, specific density 4.0
(resin)
Resin 1: Fluorine resin, Asahi Glass Co., Ltd., LF-200F, Trifluoride ethylene / vinyl monomer alternating copolymer Resin 2: Acrylic resin, Mitsubishi Rayon Co., Ltd., BR-105, methacrylic acid ester polymer Resin 3: Urethane acrylate, Sartmer, CN991, aliphatic urethane acrylate Resin 4: Acryloylmorpholine, KJ Chemicals Co., Ltd., ACMO, acrylamide-based monomer Resin 5: Acrylic monomer, Osaka Organic Chemical Industry Co., Ltd. , MEDOL-10, monofunctional acrylic monomer (dispersant)
Dispersant 1: Polymer dispersant, BYK, DISPERBYK2008, modified acrylic block copolymer Dispersant 2: Polymer dispersant, BYK, BYKJET9151, block copolymer with tertiary amine (solvent)
Solvent: Glycol ether solvent, manufactured by Nippon Embroidery Co., Ltd., diethylene glycol diethyl ether (DEDG), boiling point: 189 ° C.
(Acrylic silane)
Acrylic silane: manufactured by Shin-Etsu Chemical Co., Ltd., KBM5103, 3-acryloxypropyltrimethoxysilane (photopolymerization initiator)
Photopolymerization initiator: manufactured by BASF Japan Ltd., Irg184, α-hydroxyketone type

<Inkjet ink>
The inks of Examples 1 to 7 and Comparative Examples 1 to 3 were prepared according to the formulations (unit: parts by mass) shown in Table 1 below. Specifically, each component was mixed with a resin in a mixer and filtered to prepare an ink. Using the obtained ink, apply a commercially available fluorine paint (Bonflon # 1000SR topcoat, manufactured by AGC Cortec Co., Ltd.) to a base material (chromate-treated aluminum steel sheet) under the following inkjet conditions by air spraying at approximately 150 g / m. ² The coating was applied and dried in an environment of 200 ° C. for 3 minutes), and inkjet printing was performed to prepare a printed matter.

<Inkjet conditions>
Single pass method Dot size: 30pl
Nozzle diameter: 40 μm
Drive voltage: 80V
Pulse width: 10 μm
Frequency: 10kHz
Resolution: 400 x 400 dpi
Application amount: 7.5 g / m ²
Base material temperature: 50 ° C (heating)
Pattern: Solid pattern

<Drying conditions>
Examples 1 and 2, which are solvent-based inkjet inks, were dried in an environment of 200 ° C. for 1 minute after printing. Examples 3 to 7 and Comparative Examples 1 to 3, which are ultraviolet curable inkjet inks, were dried under the following conditions immediately after printing. Ultraviolet irradiation lamp: Metal halide lamp Irradiation intensity: 0.5 mW / cm ²
Integrated light intensity: 400mJ / cm ²
Irradiation height: 40 mm

In producing the printed matter, the initial viscosity, matte property, ink stability, and ejection stability of each ink were evaluated according to the following evaluation criteria. The results are shown in Table 1.

<Ink initial viscosity>
The prepared ink was adjusted to 50 ° C., and the viscosity (mPa · s) was measured using a B-type viscometer (TVB-20LT, rotor No. 1, rotor rotation speed 60 rpm, manufactured by Toki Sangyo Co., Ltd.). ..

<Matte>
The obtained printed matter was measured at a measuring angle of 60 ° using a gloss checker (IG331, manufactured by HORIBA, Ltd.), and the matteness was evaluated according to the following evaluation criteria.
(Evaluation criteria)
⊚: The glossiness was 10 or less.
◯: The glossiness was more than 10 and 20 or less.
Δ: The glossiness was more than 20 and 30 or less.
X: Exceeded 30.

<Ink stability>
Using a B-type viscometer (product number: TVB-20LT, manufactured by Toki Sangyo Co., Ltd.), the temperature was 50 ° C., and the rotor No. 1. The ink viscosity (mPa · s) was measured under the condition that the rotor rotation speed was 60 rpm, and the ink viscosity immediately after production and the ink viscosity one month later were evaluated for ink stability according to the following evaluation criteria.
(Evaluation criteria)
⊚: The change in ink viscosity one month after the ink viscosity immediately after production was less than 2%.
◯: The change in ink viscosity one month after the ink viscosity immediately after production was 2% or more and less than 5%.
Δ: The change in ink viscosity one month after the ink viscosity immediately after production was 5% or more and 10% or less.
X: The change in ink viscosity one month after the ink viscosity immediately after production exceeded 10%.

<Discharge stability>
Check the nozzle clogging and ink droplet scattering (a phenomenon in which the ink droplets do not become one drop of the desired size and are scattered finely) when the ink droplets are continuously ejected for 60 minutes and after the ink droplets are allowed to stand after ejection. It was evaluated according to the evaluation criteria of.
(Evaluation criteria)
⊚: There was no nozzle clogging or ink droplets scattered at all.
◯: Nozzle was not clogged.
Δ: The nozzle was partially clogged.
X: Many clogging was observed in the nozzle.

As shown in Table 1, all of the inks of Examples 1 to 7 had a small rate of change in ink viscosity and excellent storage stability. In addition, these inks have excellent ejection stability and can exhibit excellent matting properties. On the other hand, the ink of Comparative Example 1 using particles having a high specific density did not have sufficient storage stability, and also had insufficient matting property and ejection stability. The ink of Comparative Example 2 using particles having a large average particle diameter was inferior in ejection stability. The ink of Comparative Example 3 using particles having a large refractive index and a large specific gravity was inferior in matte property.

Claims (7)

It contains particles having an average particle size of 0.4 to 2.5 μm, a refractive index of 1.4 to 1.7, and a specific gravity of 2.1 or less.
The content of the particles is 0.5 to 15% by mass.
Inkjet ink , which is a radical polymerization type ultraviolet curable ink. The inkjet ink according to claim 1 , wherein the particles include spherical crosslinkable polymer fine particles. The inkjet ink according to claim 1 , wherein the particles include melamine-based beads. The inkjet ink according to any one of claims 1 to 3 , which comprises (meth) acrylic silane. The particles contain melamine-based beads and contain
The inkjet ink according to claim 4 , wherein the blending ratio (mass ratio) of the (meth) acrylic silane and the melamine-based beads is 1:10 to 1:200. A step of applying the inkjet ink according to any one of claims 1 to 5 onto a substrate by an inkjet method, and
A method for producing an inkjet print, comprising a step of irradiating the applied inkjet ink with ultraviolet rays to cure the ink jet ink. An inkjet print to which the inkjet ink according to any one of claims 1 to 5 is applied.