JP5618110B2 - Recording method, recorded matter, inkjet recording apparatus, and identification method - Google Patents

Description

  The present invention relates to a recording method, a recorded matter, an ink jet recording apparatus, and an identification method.

  In recent years, there is an increasing demand for printed materials having a glossy metallic surface on the printed surface. A printed matter having a metallic luster and a pearly luster surface has a feature that it is difficult to reproduce in addition to the appearance feature of the gloss. For example, copying and duplicating a printed matter having a metallic glossy surface using a commercially available copying machine, printer, etc., makes it difficult to capture image information of the metallic glossy or pearly glossy surface by optical scanning, and metal It is very difficult due to the lack of toner and ink that can reproduce gloss and pearl gloss.

  The metallic gloss surface includes a mirror-like high gloss surface and a matte matte gloss surface. The glossiness of these metallic gloss surfaces is defined by the specular glossiness (JIS Z8741 etc.). It is difficult to reproduce a printing with a high metallic luster with a 20 ° specular glossiness exceeding 100% even using a conventional commercial printing apparatus and a conventional printing ink. In addition, foil stamping devices such as hot stamps and cold stamps using metal foil are used. This is a method of printing by pressing a metal foil against a recording medium having a highly flat printing surface. In addition, as printing with high metallic luster, there are a method of vacuum-depositing a metal on a plastic film with a smooth printing surface, a method of printing using a metal pigment ink on a recording medium, and further pressing. Can be mentioned.

  A method for forming a metallic glossy surface having a high metallic gloss by an ink jet recording method has also been proposed. For example, in Japanese Patent Application Laid-Open No. 2002-179960, an ink composition containing a pigment formed by forming a metal film on the surface of plastic spherical particles is applied to a recording medium with an ink jet recording apparatus, and then subjected to press working. A printing technique for smoothing the surface is disclosed (Patent Document 1).

  Examples of conventional methods for forming a matte glossy surface include gravure printing using a metal pigment ink, screen printing, flexographic printing, and the like, and after forming a pattern on a recording medium in advance by pressing or the like. In addition, there are methods such as foil press printing and thermal transfer printing using metal foil.

JP 2002-179960 A

  However, the conventional printing technique exemplified above is a technique suitable for forming one kind of metallic glossy surface and pearly glossy surface having a specific glossiness on the printing surface. Accordingly, it has been difficult to form a plurality of metallic glossy and pearly glossy printed surfaces having different glossiness on one target printed matter in one printing process.

In order to form multiple metallic glossy surfaces and pearly glossy printing surfaces with different gloss levels, it is necessary to change the type of metal pigment ink and pearl pigment ink for each plate in the conventional gravure printing method and flexographic printing method. Further, in conventional foil stamp printing and thermal transfer printing, it is necessary to prepare dedicated ones such as exchanging molds for forming irregularities, printing plates, rolls, and the like. Therefore, in the conventional method, a plurality of printing devices are combined in series to form each metallic glossy surface and pearly glossy printing sequentially, or a special plate or roll is added to the printing device. There has been a tendency for printing apparatuses to become extremely complex.

  The inventor has disclosed that the glossiness of a metallic glossy surface varies depending on the arithmetic average roughness (Ra) of the surface of the metallic glossy surface, and that the arithmetic average roughness (Ra) is ink jet recording using a radiation curable ink composition. Focusing on the fact that the amount of the radiation curable ink composition can be controlled by the method and can be easily controlled by forming a pattern on the surface of the recording medium, the present invention has been achieved.

  One of the objects of the present invention is to provide a recording method capable of imparting an arbitrary glossiness to a metallic glossy surface with a simple process when forming the metallic glossy surface on a recording medium.

  One of the objects of the present invention is to provide a recorded matter that is difficult to be copied or duplicated.

  One of the objects of the present invention is to provide a method for easily identifying recorded material.

The recording method according to the present invention includes:
Forming a first dot group by ejecting droplets of an ink composition using an inkjet recording apparatus and attaching the droplets onto a recording medium;
A step of forming a second dot group by adhering a glossy ink composition containing a colorant composed of tabular particles on at least the first dot group;
including.

  According to such a method, a metallic glossy surface having an arbitrary glossiness can be easily formed on the recording medium.

In the recording method according to the present invention,
The color material composed of the tabular grains is at least one of a metal pigment and a pearl pigment.

In the recording method according to the present invention,
The material of the metal pigment may be aluminum or an aluminum alloy.

In the recording method according to the present invention,
The structure of the metal pigment or pearl pigment may be a tabular grain formed from multiple layers of thin films.

In the recording method according to the present invention,
The step of forming the first dot group can be performed using a radiation curable ink composition.

In the recording method according to the present invention,
After the step of forming the first dot group, a step of performing a curing process by irradiating the first dot group with radiation can be included.

In the recording method according to the present invention,
The step of irradiating the first dot group with the radiation may be performed by irradiating light having a wavelength of 350 nm to 450 nm.

In the recording method according to the present invention,
The step of forming the second dot group is performed by ejecting droplets of the glossy ink composition using the inkjet recording apparatus and attaching the droplets onto at least the first dot group. Can do.

In the recording method according to the present invention,
After the step of forming the second dot group, a step of forming a third dot group by further attaching a radiation curable clear ink composition;
Irradiating the third dot group with radiation and performing a curing treatment;
Can be included.

In the recording method according to the present invention,
The step of irradiating the third dot group with radiation may be performed by irradiating light having a wavelength of 350 nm to 450 nm.

In the recording method according to the present invention,
When the major axis on the plane of the colorant composed of tabular grains is X, the minor axis is Y, and the thickness is Z, the 50% average particle diameter R50 in the equivalent circle diameter determined from the area of the XY plane of the tabular grains. 0.5 to 3 μm and satisfy the condition of R50 / Z> 5.

In the recording method according to the present invention,
The first dot group is formed to have a pattern on the surface,
The pattern may have an arithmetic average roughness (Ra) of a roughness curve according to Japanese Industrial Standard JIS B0601: 2001 of 0.4 to 1.4 μm.

In the recording method according to the present invention,
The pattern can be controlled by the amount of the droplets of the ink composition in the step of forming the first dot group.

The recorded matter according to the present invention is:
Information is recorded by the recording method described above.

  Such recorded material is difficult to duplicate.

An ink jet recording apparatus according to the present invention includes:
It is used for the recording method described above.

The identification method according to the present invention includes:
A method for identifying a recorded matter as described above,
A step of observing with a microscope the particle shape of the color material composed of the tabular particles contained in the glossy ink composition forming the second dot group;
The authenticity of the recorded matter is determined based on the suitability of the particle shape of the colorant composed of the tabular grains observed with the microscope.

  According to such a method, the authenticity of the recorded matter can be easily identified.

The identification method according to the present invention includes:
A method for identifying a recorded matter as described above,
The second dot group contains a substance for identification,
Observing the second dot group with a microscope,
The authenticity of the recorded matter is determined based on the content of the identifying substance observed with the microscope.

In the identification method according to the present invention,
The identification material may be at least one selected from transparent particles, colored particles, and fluorescent materials.

The graph which plotted the arithmetic mean roughness (Ra) of the contour curve of the surface of the 1st dot group with respect to the usage-amount of a radiation curable ink composition. The graph which plotted arithmetic mean roughness (Ra), 20 degree specular glossiness, and 60 degree specular glossiness of the contour curve of the surface of the 2nd dot group with respect to the usage-amount of a radiation curable ink composition. Copy results of metallic glossy surfaces with different specular glossiness.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

1. Recording Method The recording method according to the present invention includes a step of forming a first dot group on a recording medium and a step of forming a second dot group on at least the first dot group.

  In this specification, the “dot group” refers to a deposit of an ink composition formed on a print surface of a printed matter such as a character, an image, or a dot (solid) shape.

1.1. Step of forming first dot group The step of forming the first dot group is performed by ejecting droplets of the ink composition and depositing the droplets on the recording medium using an ink jet recording apparatus. The first dot group can be formed so as to have a pattern (for example, an uneven shape) on the surface.

1.1.1. Inkjet recording apparatus The inkjet recording apparatus used in this step is not particularly limited as long as it can perform recording by ejecting ink droplets and attaching the droplets to a recording medium.

  As a recording method of an ink jet recording apparatus, for example, a strong electric field is applied between a nozzle and an acceleration electrode placed in front of the nozzle, and ink is continuously ejected from the nozzle in the form of droplets. A method in which a print information signal is applied to a deflection electrode during recording, or a method in which ink droplets are ejected in response to a print information signal without being deflected (electrostatic suction method). In addition, a system that forcibly ejects ink droplets by mechanically vibrating the nozzle with a crystal resonator, etc., a system that simultaneously applies pressure and printing information signals to ink liquid with piezoelectric elements, and ejects and records ink droplets (Piezo method), a method in which an ink liquid is heated and foamed with a microelectrode according to a print information signal, and an ink droplet is ejected and recorded (thermal jet method).

Examples of the ink jet recording apparatus used in this step include an ink jet recording head, a main body, a tray, a head driving mechanism, a carriage, and an ultraviolet irradiation device mounted on a side surface of the carriage. The ink jet recording head includes, for example, four color inks of cyan, magenta, yellow, and black and an ink cartridge for ink jet recording, and can be configured to perform full color printing. Further, it is also possible to use an intermediate color, dark color, light color, white or transparent ink, and an ink cartridge for inkjet recording. In this step, the at least one ink jet recording ink cartridge is filled with a radiation curable ink composition and installed. In addition, the ink jet recording apparatus includes a dedicated control board and the like, and can control the ink ejection amount, ejection timing, and head drive mechanism scanning of the ink jet recording head.

  The ink jet recording apparatus is provided with a plurality of ink jet recording cartridges, and at least one of them can store an ink composition suitable for this process described later. Further, other ink jet recording cartridges can store normal ink, respectively.

  If such an ink jet recording apparatus is used, the first dot group can be easily formed by spraying and adhering the ink composition onto the recording medium.

  Further, an ultraviolet irradiation device for irradiating ultraviolet rays can be mounted inside the ink jet recording apparatus, the paper discharge port, and the side surface of the carriage in the apparatus. As the ultraviolet irradiation device, it is possible to conduct light from a metal halide lamp, a xenon lamp, a carbon arc lamp, a chemical lamp, a low-pressure mercury lamp, a high-pressure mercury lamp or the like by guiding it to a dot group with a light guide or the like. Moreover, as a light source, it can carry out using what was marketed, such as H lamp, D lamp, and V lamp which can be obtained from Fusion System etc., for example. Further, as the light source, an ultraviolet light emitting semiconductor element such as an ultraviolet light emitting diode (ultraviolet LED) or an ultraviolet light emitting semiconductor laser can be used, and ultraviolet light from such a light source is attached to the recording medium or the recording medium in the ink jet recording apparatus. The irradiated droplet can be irradiated.

1.1.2. Recording Medium The recording medium used in this step is not particularly limited as long as the ink composition droplets can be adhered by an ink jet recording apparatus. For recording media, surface treated paper such as coated paper, art paper, cast coated paper, olefin synthetic paper, and glossy, matte vinyl chloride sheets, tarpaulins, olefins such as PE, PP, polycarbonate, acrylic Resin, plastic film such as PET film, acrylic resin, PVC, ABS resin, urethane resin, etc. The range of change in glossiness of the metallic glossy surface formed on the recording medium can be widened.

Examples of coated paper, for example, can include those coated with at least one surface 7g / m ² ~20g / m ² of white paint woodfree or wood paper base. These are sometimes called high-quality coated paper or medium-quality coated paper. The types of coated paper include light coated paper with a small amount of white paint applied (for example, about 7 g / m ² per side), mat coated paper with reduced gloss, and mirror coated paper with high surface gloss. be able to.

As an example of art paper, for example, a paper in which a white paint is applied to high-quality paper by about 20 g / m ² per side, and a high pressure is applied by a roll or the like to make the surface smooth is exemplified. Art paper includes matte art paper, high-quality art paper, and average art paper. As an example of the cast coated paper, for example, a paper in which a white paint is coated at least 22 g / m ² per side on a high-quality paper and a high pressure is applied by a roll or the like to make the surface smooth can be mentioned.

The recording medium described above is not limited in surface flatness, and may be any of a gloss system, a mat system, and a dull system. Commercially available recording media include pearl coated paper (available from Mitsubishi Paper Co., Ltd.), aurora coated paper (available from Nippon Paper Industries Co., Ltd.), glossy vinyl chloride sheet (for example, trade name SV-G-610G, SPVC-G-1270T (manufactured by Roland DG Corporation), PET film (for example, trade name XEROX FILM <no frame>: manufactured by Fuji Xerox Co., Ltd.), and the like.

1.1.3. Ink composition The first dot group formed in this step is composed of an ink composition attached on a recording medium by the above-described ink jet recording apparatus. The ink composition used in this step has a function of leaving at least a part of the components on the recording medium.

  Examples of the ink composition remaining on such a recording medium include a radiation curable ink composition, a general pigment ink composition, and a hot-melt type ink composition. The hot-melt type ink composition contains a wax component and can be adjusted to a viscosity that can be discharged by an ink jet recording apparatus by heating and melting. Then, when the ink composition is deposited on the recording medium, it is cooled and the temperature is lowered to solidify.

  In the radiation curable ink composition, the general pigment ink composition, and the hot melt type ink composition exemplified above, at least a part of the components remain on the recording medium, and the ink composition remains. A pattern (for example, an uneven shape) can be formed on the surface. For example, a general pigment ink composition contains at least a pigment as a component that is not absorbed by the recording medium, and a pattern can be formed on the surface by the pigment remaining on the recording medium. Further, for example, at least a part of the hot-melt type ink composition may remain on the recording medium by adjusting the permeability to the recording medium, the viscosity of the composition, the temperature at which the ink composition is attached, and the like. Thus, a pattern can be formed on the surface. Hereinafter, the radiation curable ink composition particularly suitable in this step will be described.

1.1.4. Radiation curable ink composition The first dot group formed in this step can be composed of a radiation curable ink composition attached on a recording medium by the ink jet recording apparatus. The radiation curable ink composition that can be used in this step contains at least a polymerizable compound and a radiation polymerization initiator.

1.1.4.1. Polymerizable compound Examples of the polymerizable compound contained in the radiation curable ink composition usable in this step include a monofunctional polymerizable compound and a polyfunctional polymerizable compound. These polymerizable compounds are not particularly limited as long as they are compounds that cause a polymerization reaction upon application of energy and are cured, and are used regardless of the type of monomer, oligomer, linear polymer, or dendritic polymer. can do. More specific examples of the polymerizable compound include radically polymerizable compounds.

Examples of the radical polymerizable compound that can be used in the radiation curable ink composition include (meth) acrylates, (meth) acrylamides, aromatic vinyls, allyl compounds, N-vinyl compounds, vinyl esters (vinyl acetate, Vinyl propionate, vinyl versatate, etc.), allyl esters (eg, allyl acetate), halogen-containing monomers (vinylidene chloride, vinyl chloride, etc.), vinyl ethers (methyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, methoxy vinyl ether, 2- Ethylhexyl vinyl ether, methoxyethyl vinyl ether, cyclohexyl vinyl ether, chloroethyl vinyl ether, etc.), vinyl cyanide ((meth) acrylonitrile, etc.), olefins (ethylene, propylene) Etc.), and the like. In this specification, “
“(Meth) acrylate” when referring to both and / or “acrylate” and “(meth) acryl” when referring to both and / or “acryl” and “methacryl” is there.

  Monofunctional (meth) acrylates include hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, tert-octyl (meth) acrylate, isoamyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, stearyl (Meth) acrylate, isostearyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-n-butylcyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, benzyl (meth) acrylate, 2- Ethylhexyl diglycol (meth) acrylate, butoxyethyl (meth) acrylate, 2-chloroethyl (meth) acrylate, 4-bromobutyl (meth) acrylate, cyanoethyl (meth) Acrylate, benzyl (meth) acrylate, butoxymethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, alkoxymethyl (meth) acrylate, alkoxyethyl (meth) acrylate, 2- (2-methoxyethoxy) ethyl (meth) Acrylate, 2- (2-butoxyethoxy) ethyl (meth) acrylate, 2,2,2-tetrafluoroethyl (meth) acrylate, 1H, 1H, 2H, 2H-perfluorodecyl (meth) acrylate, 4-butylphenyl (Meth) acrylate, phenyl (meth) acrylate, 2,4,5-tetramethylphenyl (meth) acrylate, 4-chlorophenyl (meth) acrylate, phenoxymethyl (meth) acrylate, phenoxyethyl (meth) acrylate Glycidyl (meth) acrylate, glycidyloxybutyl (meth) acrylate, glycidyloxyethyl (meth) acrylate, glycidyloxypropyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, hydroxyalkyl (meth) acrylate, 2- Hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, dimethylaminoethyl (meth) acrylate , Diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, trimethoxysilylpropyl (meth) acrylate Acrylate, trimethoxysilylpropyl (meth) acrylate, trimethylsilylpropyl (meth) acrylate, polyethylene oxide monomethyl ether (meth) acrylate, oligoethylene oxide monomethyl ether (meth) acrylate, polyethylene oxide (meth) acrylate, oligoethylene oxide (meth) acrylate, Oligoethylene oxide monoalkyl ether (meth) acrylate, polyethylene oxide monoalkyl ether (meth) acrylate, dipropylene glycol (meth) acrylate, polypropylene oxide monoalkyl ether (meth) acrylate, oligopropylene oxide monoalkyl ether (meth) acrylate, 2 -Methacryloyloxyethyl succinic acid, 2-methacrylo Loxyhexahydrophthalic acid, 2-methacryloyloxyethyl-2-hydroxypropyl phthalate, butoxydiethylene glycol (meth) acrylate, trifluoroethyl (meth) acrylate, perfluorooctylethyl (meth) acrylate, 2-hydroxy-3-phenoxy Examples include propyl (meth) acrylate, EO-modified phenol (meth) acrylate, EO-modified cresol (meth) acrylate, EO-modified nonylphenol (meth) acrylate, PO-modified nonylphenol (meth) acrylate, and EO-modified-2-ethylhexyl (meth) acrylate. It is done.

As polyfunctional (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate 2,4-dimethyl-1,5-pentanediol di (meth) acrylate, butylethylpropanediol di (meth) acrylate, ethoxylated cyclohexanemethanol di (meth) acrylate, polyethylene glycol di (meth) acrylate, oligoethylene glycol Di (meth) acrylate, ethylene glycol di (meth) acrylate, 2-ethyl-2-butyl-butanediol di (meth) acrylate, hydroxypivalate neopentyl glycol di (meth) acrylate, O-modified bisphenol A di (meth) acrylate, bisphenol F polyethoxydi (meth) acrylate, polypropylene glycol di (meth) acrylate, oligopropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 2-ethyl Bifunctional such as 2-butyl-propanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, propoxylated ethoxylated bisphenol A di (meth) acrylate, tricyclodecane di (meth) acrylate, etc. (Meth) acrylate is mentioned.

  Furthermore, as polyfunctional (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, alkylene oxide modified tri (meth) acrylate of trimethylolpropane, pentaerythritol tri (meth) acrylate , Dipentaerythritol tri (meth) acrylate, trimethylolpropane tri ((meth) acryloyloxypropyl) ether, isocyanuric acid alkylene oxide modified tri (meth) acrylate, propionate dipentaerythritol tri (meth) acrylate, tri ( (Meth) acryloyloxyethyl) isocyanurate, hydroxypivalaldehyde-modified dimethylolpropane tri (meth) acrylate, sorbitol tri (meth) a Relate, propoxylated trimethylolpropane tri (meth) acrylate, ethoxylated glycerol tri (meth) acrylate: trifunctional, pentaerythritol tetra (meth) acrylate, sorbitol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, Propionic acid dipentaerythritol tetra (meth) acrylate, ethoxylated pentaerythritol tetra (meth) acrylate: tetrafunctional, sorbitol penta (meth) acrylate, dipentaerythritol penta (meth) acrylate: pentafunctional, dipentaerythritol hexa ( (Meth) acrylate, sorbitol hexa (meth) acrylate, phosphazene alkylene oxide modified hexa (meth) acrylate, cap Lactone-modified dipentaerythritol hexa (meth) acrylate or hexafunctional, and the like.

  Furthermore, examples of the polyfunctional (meth) acrylate include compounds having a plurality of (meth) acryloyl groups in the molecule. For example, a compound in which a plurality of (meth) acryloyl groups are bonded to a linear polymer, And a compound in which a plurality of (meth) acryloyl groups are bonded to the polymer. A specific example of a compound in which a plurality of (meth) acryloyl groups are bonded to a dendritic polymer is a compound available from Osaka Organic Chemical Industry Co., Ltd. under the trade name: Biscote # 1000. The compound is a hyperbranched polymer synthesized by branching a functional group with dipentaerythritol as a core, and since the density of acryloyl groups near the surface of the polymer molecule is high, it can be suitably used as a polymerizable compound. it can.

  (Meth) acrylamides include (meth) acrylamide, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, Nn-butyl (meth) acrylamide, Nt -Butyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-methylol (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) Examples include acrylamide and (meth) acryloylmorpholine.

Specific examples of aromatic vinyls include styrene, methyl styrene, trimethyl styrene, ethyl styrene, isopropyl styrene, chloromethyl styrene, methoxy styrene, acetoxy styrene, chloro styrene, dichloro styrene, bromo styrene, vinyl benzoic acid methyl ester, 3-methylstyrene, 4-methylstyrene, 3-ethylstyrene, 4-ethylstyrene, 3-propylstyrene, 4-propylstyrene, 3-butylstyrene, 4-butylstyrene, 3-hexylstyrene, 4-hexylstyrene, 3-octylstyrene, 4-octylstyrene, 3- (2-ethylhexyl) styrene, 4- (2-ethylhexyl) styrene, allylstyrene, isopropenylstyrene, butenylstyrene, octenylstyrene, 4-t- Butoxycarbonyl styrene, 4-methoxystyrene, and a 4-t-butoxystyrene.

The allyl compound has a 2-propenyl structure (—CH ₂ CH═CH ₂ ). The 2-propenyl group is also called an allyl group, and is a common name in the IUPAC nomenclature. Specific examples of allyl compounds include, for example, ethylene glycol monoallyl ether, allyl glycol (for example, available from Nippon Emulsifier Co., Ltd.), trimethylolpropane diallyl ether, pentaerythritol triallyl ether, glycerin monoallyl ether (above, for example, And a polyoxyalkylene compound having an allyl group, which is a trade name of UNIOX, UNILOP, polyserine, UNISafe (available from NOF Corporation), and the like.

The N-vinyl compound has a structure in which a vinyl group is bonded to nitrogen (> N—CH═CH ₂ ). The N-vinyl compound has radical polymerizability. Specific examples of the N-vinyl compound include, for example, N-vinylformamide, N-vinylcarbazole, N-vinylindole, N-vinylpyrrole, N-vinylacetamide, N-vinylpyrrolidone, N-vinylcaprolactam, and their Derivatives, and N-vinylformamide is particularly preferable among these compounds. N-vinylformamide can be obtained from Arakawa Chemical Industries, Ltd., for example.

  The radiation curable ink composition can contain a plurality of the polymerizable compounds exemplified above.

  The content of the polymerizable compound in the radiation curable ink composition is suitably 50% by mass to 95% by mass, preferably 60% by mass to 92% by mass, and more preferably 70% by mass with respect to the entire composition. % To 90% by mass.

1.1.4.2. Radiation polymerization initiator The radiation-curable ink composition usable in this step contains a radiation polymerization initiator. The radiation polymerization initiator used in the radiation curable ink composition can generate radicals by radiation. Examples of radiation that can generate radicals of the radiation polymerization initiator include ultraviolet rays, visible light, far ultraviolet rays, g-rays, h-rays, i-rays, KrF excimer laser light, ArF excimer laser light, and electrons in the range of 400 nm to 200 nm. Examples thereof include a ray, an X-ray, a molecular beam, and an ion beam.

  Examples of the radiation polymerization initiator contained in the radiation curable ink composition include aromatic ketones, aromatic onium salt compounds, organic peroxides, hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, and aziniums. Examples thereof include compounds, metallocene compounds, active ester compounds, and compounds having a carbon halogen bond. Specific examples of the radiation polymerization initiator that can generate radicals by ultraviolet rays include benzyldimethyl ketal, α-hydroxyalkylphenone, α-aminoalkylphenone, acylphosphine oxide, oxime ester, and thioxanthone. , Α-dicarbonyl, and anthraquinone.

Specific examples of the radiation polymerization initiator include Vicure 10, 30 (Staffer
Chemical, Inc.), Irgacure 127, 184, 500, 651, 2959, 907, 369, 379, 754, 1700, 1800, 1870, 819, OXE01, Darocur 1173, TPO, ITX (manufactured by Ciba Specialty Chemicals), Examples include Quantacure CTX (manufactured by Aceto Chemical), Kayacure, DETX-S (manufactured by Nippon Kayaku Co., Ltd.), ESACURE KIP150 (manufactured by Lamberti), and the like.

  The radiation polymerization initiator generates a radical upon receiving radiation. The generated radical can act as a polymerization initiator for the polymerizable compound.

1.1.4.3. Other components The radiation curable ink composition usable in this step comprises, in addition to the polymerizable compound and the radiation polymerization initiator, a coloring material, a polymerization accelerator, a thermal radical polymerization inhibitor, a surfactant, and a wetting agent. , Osmotic solvents, pH adjusters, preservatives, antifungal agents, and the like. Further, it may contain leveling additives, matting agents, polyester resins for adjusting the physical properties of recorded materials, polyurethane resins, vinyl resins, acrylic resins, rubber resins, and waxes as necessary. it can.

  The coloring material that can be used in the radiation curable ink composition may be either a dye or a pigment.

  Examples of the dye include various dyes that are usually used in inkjet recording, such as direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes, vat dyes, and soluble vat dyes.

  There is no special restriction | limiting as a pigment, An inorganic pigment and an organic pigment can be mentioned. As the inorganic pigment, in addition to titanium oxide and iron oxide, carbon black produced by a known method such as a contact method, a furnace method, or a thermal method can be used. Organic pigments include azo pigments (including azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments), polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinofullerone pigments). Dye chelates (for example, basic dye chelates, acidic dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, and the like can be used.

  Among the pigments, carbon black includes C.I. I. Pigment black 7, for example, No. available from Mitsubishi Chemical Corporation. 2300, no. 900, MCF88, No. 33, no. 40, no. 45, no. 52, MA7, MA8, MA100, no. Raven5750, 5250, 5000, 3500, 1255, 700, etc. available from Columbia Chemical Company 2200B, etc. Also, Regal400R, 330R, 660R, MoguL, available from Cabot 700, Monarch 800, 880, 900, 1000, 1100, 1300, 1400, etc. are further available from Degussa, such as ColorBlack FW1, FW2, FW2V, FW18, FW200, ColorBlackS150, S160. , S170, Printex35, U, V, 140U, Special Black6, 5, 4A, 4 and the like.

  Examples of yellow pigments that can be used in the radiation curable ink composition include C.I. I. Pigment Yellow 1, 2, 3, 12, 13, 14, 16, 17, 73, 74, 75, 83, 93, 95, 97, 98, 109, 110, 114, 120, 128, 129, 138, 150, 151, 154, 155, 180, 185, 213 and the like.

  Examples of magenta pigments that can be used in the radiation curable ink composition include C.I. I. Pigment Red 5, 7, 12, 48 (Ca), 48 (Mn), 57 (Ca), 57: 1, 112, 122, 123, 168, 184, 202, 209, C.I. I. Pigment violet 19 and the like.

  Examples of cyan pigments that can be used in the radiation curable ink composition include C.I. I. And CI Pigment Blue 1, 2, 3, 15: 3, 15: 4, 60, 16, and 22.

  The average particle size of the pigment that can be used in the radiation curable ink composition is preferably in the range of 10 nm to 200 nm, more preferably in the range of 50 nm to 150 nm.

  The amount of the pigment that can be used in the radiation curable ink composition is preferably 0.1% by mass to 25% by mass, and more preferably 0.5% by mass to 15% by mass.

  When the radiation curable ink composition contains a pigment, a dispersant or a surfactant can be included in order to obtain a good dispersion of the pigment. As a preferable dispersant, a dispersant conventionally used for preparing a pigment dispersion, for example, a polymer dispersant can be used. Specific examples of the polymer dispersant include polyoxyalkylene polyalkylene polyamine. Specific examples of the polyoxyalkylene polyalkylene polyamine include, for example, Discole N-503, N-506, N-509, N-512, N-515, N-518, N-520 (Daiichi Kogyo). Pharmaceutical Co., Ltd.).

  When a color material is contained in the radiation curable ink composition, the first dot group functions as a dot group for recording a normal image or the like in addition to the function of forming a pattern (for example, uneven shape) on the surface. be able to.

  The radiation curable ink composition may further contain a polymerization accelerator. The polymerization accelerator that can be used in the radiation curable ink composition is not particularly limited, and examples thereof include Darocur EHA, EDB (available from Ciba Specialty Chemicals).

  The radiation curable ink composition can also contain a thermal radical polymerization inhibitor. By containing a thermal radical polymerization inhibitor, the storage stability of the radiation curable ink composition can be improved. Examples of the thermal radical polymerization inhibitor include Irgastab UV-10 (available from Ciba Specialty Chemicals).

  Furthermore, the radiation curable ink composition can contain a surfactant in order to improve storage stability and the like. As the surfactant, for example, polyester-modified silicone or polyether-modified silicone can be used as a silicone-based surfactant, and it is particularly preferable to use polyether-modified polydimethylsiloxane or polyester-modified polydimethylsiloxane. Specific examples include BYK-347, BYK-348, BYK-UV3500, -UV3510, -UV3530, and -UV3570 (available from Big Chemie Japan KK).

  The step of forming the first dot group described above is performed by ejecting droplets of an ink composition using an ink jet recording apparatus and attaching the droplets onto a recording medium. The dot group is formed so as to have a pattern (for example, an uneven shape) on the surface.

1.2. Step of Forming Second Dot Group The step of forming the second dot group is performed by attaching a glossy ink composition containing a color material composed of tabular particles on at least the first dot group.

1.2.1. Glossy ink composition adhesion method Glossy ink composition adhesion methods include inkjet recording methods, stencil printing such as screen printing, lithographic printing such as offset printing, relief printing such as flexographic printing, and intaglio printing such as gravure printing. And a coating method using a brush or a brush. Among these methods, the inkjet recording method is particularly preferable because it is easy to attach the glossy ink composition so as not to deform the surface pattern formed on the surface of the first dot group. When this step is performed by the inkjet recording method, gloss ink is used instead of the ink composition for forming the first dot group in the inkjet recording apparatus described in the section “1.1.1. Inkjet recording apparatus”. It can be carried out by filling the composition.

  The glossy ink composition may be attached to at least the first dot group, and may be attached to the entire first dot group and partially attached to the first dot group. Further, the glossy ink composition may be attached to a portion where the first dot group is not formed on the recording medium.

1.2.2. Glossy ink composition The 2nd dot group formed at this process is comprised from the glossy ink composition containing the coloring material which consists of tabular grain. The glossy ink composition used in this step can form a metallic glossy surface when attached to an object. The gloss ink composition contains a color material composed of tabular particles, an organic solvent, and a resin.

1.2.2.1. Color material comprising tabular grains The color material contained in the glossy ink composition is arbitrary as long as it has a tabular grain shape. A “tabular grain” refers to a grain having a substantially flat surface (XY plane) and a substantially uniform thickness (Z).

  The colorant composed of tabular grains is 50% of the equivalent circle diameter determined from the area of the XY plane of the tabular grains, where X is the major axis on the plane of the tabular grains, Y is the minor axis, and Z is the thickness. It is more preferable that the average particle diameter R50 is 0.5 to 3 μm and the condition of R50 / Z> 5 is satisfied.

  The “equivalent circle diameter” is the diameter of a circle having the same area as the area when the XY plane of the tabular grain is projected in the Z direction. The equivalent circle diameter can be measured by, for example, a particle image analyzer (for example, FPIA-2100, FPIA-3000, FPIA3000S manufactured by Sysmex Corporation), image analysis of a microscope observation result, or the like.

  The 50% average particle diameter R50 of the equivalent-circle diameter of the tabular grains is a distribution of the number (frequency) of grains relative to the equivalent-circle diameter by measuring the equivalent circle diameter of a sufficient number of tabular grains in the system. Sometimes the total number of particles measured refers to an equivalent circle diameter of 50%.

  The 50% average particle diameter R50 of the equivalent circle diameter determined from the area of the XY plane of the tabular grains is preferably 0.5 to 3 μm, preferably 0.75 to 2 μm, from the viewpoint of metallic luster and printing stability. More preferably it is.

  The maximum equivalent particle diameter Rmax obtained from the area of the XY plane of the tabular grains is 10 μm in order to prevent clogging of the nozzles when printing with an ink jet recording apparatus using the glossy ink composition. The following is preferable.

Further, the color material composed of such tabular grains is more preferably a metal pigment and a pearl pigment in that a good metallic gloss surface can be formed. Hereinafter, metal pigments and pearl pigments having a tabular grain shape will be described.

  In the case of selecting a metal pigment and a pearl pigment as the color material having a flat particle shape, commercially available products can be used, and in the case of metal particles, a metal vapor deposition film can be crushed.

  Examples of the pearl pigment include clay minerals having a layered structure such as general pearl paints, mica, talc, kaolin, bentonite, smectite, sepiolite, bamicurite, montmorillonite, and sericite blended in ink. Furthermore, the material processed into a flat plate shape, for example, mica processed to a thickness of 0.01 μm to 1 μm and a particle diameter of 2 μm to 20 μm, is coated with titanium dioxide or iron oxide to form a thin film of multiple layers. Thus, a flat pigment with improved pearl luster can also be suitably used.

  In addition, examples of a method for producing metal tabular grains include the following. First, a peeling resin layer is provided on a sheet-like base material, and a metal or metal alloy layer is laminated thereon by a method such as vapor deposition, ion plating, or sputtering. At this time, the metallic luster can be enhanced by setting the thickness of the metal or metal alloy layer to 20 to 100 nm. Next, peeling is performed at the interface between the peeling resin layer and the metal or metal alloy layer to obtain a metal or metal alloy layer. Then, the metal or metal alloy layer is mechanically pulverized. It is obtained by screening and collecting tabular grains having a target particle diameter from the pulverized product. In addition, such a metal pigment can be formed by laminating a plurality of metal alloy layers, and further layers can be laminated on the metal alloy layer. If the metal pigment is formed from a multilayer of thin films, it can be suitably used as a metal pigment with further improved metallic luster.

  The tabular metal particles are preferably made of aluminum or an aluminum alloy. In the case of selecting an aluminum alloy, the other elements contained in the aluminum are not limited as long as the aluminum alloy can exhibit a metallic luster. Examples of the alloy element of aluminum include at least one selected from silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, and copper.

  The above-described metal pigment and pearl pigment are both tabular grains. When the major axis on the plane of the tabular grains is X, the minor axis is Y, and the thickness is Z, the area of the tabular grains in the XY plane The 50% average particle diameter R50 of the equivalent circle diameter obtained is 0.5 to 3 μm, and the condition of R50 / Z> 5 can be satisfied. Therefore, a favorable metallic luster can be expressed by the second dot group.

  Since such tabular grains have a shape in which the Z direction of the tabular grains is easily aligned with the normal direction of the adhesion surface when the second dot group is adhered, the thickness uniformity of the second dot group is improved. Can be increased. Therefore, it becomes easy to reflect the surface pattern of the ground (for example, the first dot group) on the upper surface of the second dot group. Thereby, since the pattern formed by the first dot group can be reproduced on the surface of the second dot group, an arbitrary metallic glossy surface corresponding to the change in the pattern of the surface of the first dot group can be set to the second. It can be formed on the surface of a dot group.

1.2.2.2. Organic solvent The glossy ink composition contains an organic solvent. The organic solvent is preferably a polar organic solvent such as alcohols (methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol, isopropyl alcohol, and fluorides thereof), ketones (acetone, methyl ethyl ketone, cyclohexanone, etc.), Carboxylic acid esters (methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, etc.), ethers (diethyl ether, dipropyl ether, tetrahydrofuran, dioxane, etc.), lactones (γ-butyrolactone, δ-valerolactone, ε-caprolactone, etc.) can be used.

  As the organic solvent, those which are liquid at normal temperature and pressure, are colorless and have little odor are preferable. As such a preferable organic solvent, an alkylene glycol ether can be exemplified, and the organic solvent of the present embodiment preferably includes an alkylene glycol ether. Further, as the organic solvent, those having an ether group and a hydroxyl group in the molecule and having the characteristics of both alcohols and ethers are preferable. An ether can be mentioned, and the organic solvent of the present embodiment further preferably contains an alkylene glycol monoether.

  Examples of the alkylene glycol ether include aliphatic ethers such as methyl ether, methyl ether, n-propyl ether, i-propyl ether, n-butyl ether, i-butyl ether, hexyl ether and 2-ethylhexyl ether, allyl having a double bond. Examples include ethers such as ether and phenyl ether.

  Examples of the alkylene glycol portion of the alkylene glycol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, and tetrapropylene glycol.

  Specific examples of alkylene glycols suitable as organic solvents are given below. Specific examples of the alkylene glycol monoether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol mono Ethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene Glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and the like.

  Specific examples of the alkylene glycol diether include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, and triethylene glycol diether. Butyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether Le, and the like.

  Furthermore, an alkylene glycol ether derivative such as propylene glycol monomethyl ether acetate can also be used.

1.2.2.3. Resin Resin contained in the glossy ink composition used in this step includes acrylic resin, styrene-acrylic resin, rosin-modified resin, terpene resin, polyester resin, polyamide resin, epoxy resin, vinyl chloride resin, vinyl chloride-acetic acid Examples thereof include vinyl copolymers, fiber-based resins (for example, cellulose acetate butyrate and hydroxypropyl cellulose), polyvinyl butyral, polyvinyl alcohol, and polyurethane.

  Further, as the resin, non-aqueous emulsion type polymer fine particles (NAD = Non Aqueous Dispersion) can also be contained in the gloss ink composition of this step. This is a dispersion in which fine particles such as polyurethane resin, acrylic resin, and acrylic polyol resin are stably dispersed in an organic solvent. Examples of the polyurethane resin include Sanprene IB-501 and IB-F370 manufactured by Sanyo Chemical Industries, and examples of the acrylic polyol resin include N-2043-60MEX manufactured by Harima Chemicals.

1.2.2.4. Other components The glossy ink composition used in this step comprises at least one of the above-mentioned metal pigments and pearl pigments, an organic solvent and a resin, a substance for identification, a coloring material, a surfactant, a wetting agent, a penetrating solvent, You may contain antiseptic | preservative, an antifungal agent, etc. Substances such as coloring materials, surfactants, wetting agents, penetrating solvents, preservatives, and antifungal agents can be added to the radiation curable ink composition described in “1.1.4.3. Other components”. Same as substance.

  Examples of the identification substance include at least one selected from transparent particles, colored particles, and fluorescent substances. When such an identification substance is contained in the glossy ink composition, the identification substance is mixed into the second dot group, and therefore, for example, it is possible to easily determine the authenticity of the obtained recorded matter (details are given below). Will be described later).

1.3. Step of curing the first dot group In the recording method of the present invention, when the first dot group is formed of a radiation curable ink composition, the first dot group is added after the step of forming the first dot group. A step of curing treatment can be added.

  When the first dot group is formed of the radiation curable ink composition, the first dot group is cured by irradiating with radiation in this step. The radiation is irradiated with a radiation polymerization initiator that can generate radicals used in the radiation curable ink composition. The radiation is the same as that described in the section “1.1.4.2. Radiation polymerization initiator”, and the generation method is also the same. Among these, as the radiation, it is more preferable to use light having a wavelength of 350 to 450 nm in view of simplification of the apparatus and safety. In that case, it is desirable to select a radiation polymerization initiator that easily generates radicals with light having a wavelength of 350 to 450 nm.

  As a method of irradiating the radiation, it can be carried out by introducing the radiation to the first dot group with a light guide or the like from the inside of the ink jet recording apparatus or at the paper discharge port or from the outside of the ink jet recording apparatus. Further, as described above, an ultraviolet irradiation device can be provided on the side of the carriage or the like in the ink jet recording apparatus, and the ultraviolet irradiation can be performed following the scanning of the carriage for forming the first dot group.

The curing process for the first dot group can be performed at any time after the first dot group is formed and before the second dot group is formed. When an ultraviolet irradiation device is provided on the carriage side surface in the ink jet recording apparatus and the ultraviolet irradiation is performed following the scanning of the carriage for forming the first dot group, the curing process is performed immediately after the formation of the first dot group. be able to. In addition, after the predetermined first dot group is formed on the printing surface of the recording medium, the printing surface can be irradiated with ultraviolet rays to be cured. Furthermore, the pattern shape formed on the surface of the first dot group can be controlled by adjusting the fluidity of the radiation curable ink composition and the timing of performing the curing treatment.

1.4. Surface shape of first dot group The surface of the first dot group can have a pattern (for example, an uneven shape). The surface pattern of the first dot group can be measured by, for example, a surface shape measuring device or a surface roughness meter. The surface pattern of the first dot group can be characterized by, for example, the arithmetic average roughness (Ra) of the contour curve in Japanese Industrial Standard (JIS) B0601: 2001. By the process of forming the first dot group and the process of hardening the first dot group, a pattern having an Ra value in the range of 0.4 to 1.4 μm can be applied to the surface of the first dot group. .

The range of the Ra value on the surface of the first dot group is based on the following experimental results by the inventors. As a recording medium, a white vinyl chloride sheet (SPVC-G-1270T manufactured by Roland DG Corporation) was prepared. A radiation curable ink composition was printed on the sheet using an ink jet recording apparatus (PX-7500, manufactured by Seiko Epson Corporation). A solid pattern was adopted as the printing pattern. The radiation curable ink composition used was ethylene glycol monoallyl ether = 71.6 mass% and biscoat # 1000 = 20.0 mass% as a polymerizable compound, and Irgacure 819 = 6.4 mass as a photopolymerization initiator. %, And Irgacure 127 = 1.6% by mass, and the additive used was BYK-UV3500 = 0.2% by mass and IrgastabUV-10 = 0.2% by mass. After printing the solid pattern, the solid pattern was irradiated with ultraviolet rays by an ultraviolet irradiation light source so that the integrated light amount at a wavelength of 365 nm was 400 mJ / cm ² .

At this time, a plurality of solid patterns having different amounts (mg / cm ² ) of radiation curable ink composition were formed. And each surface of the obtained solid pattern (equivalent to a 1st dot group) was measured with the surface shape measuring apparatus (Keyence Corporation laser microscope VK-9700), and the outline curve was obtained. The arithmetic mean roughness Ra of the contour curve of each solid pattern was determined using the same apparatus. FIG. 1 is a graph in which the arithmetic average roughness Ra (%) is plotted against the ink usage (mg / cm ² ).

  As shown in FIG. 1, the arithmetic average roughness Ra of the surface of the first dot group is continuous depending on the amount of radiation curable ink composition attached to the recording medium in the step of forming the first dot group. Can be changed. In addition, it is found that the Ra of the surface of the first dot group and the amount of the radiation curable ink composition attached to the recording medium in the step of forming the first dot group have a substantially linear correlation. It was.

1.5. Pattern formation method When the radiation curable ink composition is used in the step of forming the first dot group and the step of curing the first dot group is performed, the surface of the first dot group formed by these steps is applied. Since a pattern such as a concavo-convex shape is formed, it can be used as a pattern forming method. That is, as a pattern forming method, using an inkjet recording apparatus, a droplet of a radiation curable ink composition is ejected, and the droplet is deposited on a recording medium to form a first dot group; And a step of curing the one dot group.

  Such a pattern forming method can easily give a pattern having an Ra value in the range of 0.4 to 1.4 μm to the surface of the first dot group formed on the recording medium. In such a pattern forming method, the Ra value can be controlled by the adhesion amount of the radiation curable ink composition deposited on the recording medium.

1.6. Third Dot Group The recording method of the present invention further includes a step of forming a third dot group by attaching a radiation curable clear ink composition on the second dot group, and a step of curing the third dot group. , Can have.

  The third dot group is formed by a radiation curable clear ink composition. “Clear ink” refers to a function of protecting at least one of the recording medium, the first dot group, and the second dot group from mechanical friction or the like by being attached to the surface of the recorded material. ) "Or an ink capable of exhibiting a function of imparting a transparent color to the recorded matter. The composition is the same composition as the gloss ink composition described above, and is an ink composition in which the resin component is increased except for the pigment or the radiation curable ink composition described above, which does not contain a pigment as a coloring material. It is preferable that

  The radiation curable clear ink composition used in the step of forming the third dot group contains at least a polymerizable compound and a radiation polymerization initiator. The polymerizable compound and radiation polymerization initiator used in the radiation curable clear ink composition are described in the sections “1.1.4.1. Polymerizable compound” and “1.1.4.2. Radiation polymerization initiator”. The description is omitted because it is the same as that described in.

  The radiation curable clear ink composition used in the step of forming the third dot group includes, in addition to the polymerizable compound and the radiation polymerization initiator, a coloring material, a polymerization accelerator, a thermal radical polymerization inhibitor, a surfactant, A wetting agent, a penetrating solvent, a pH adjusting agent, an antiseptic, an antifungal agent and the like may be contained. Further, it may contain leveling additives, matting agents, polyester resins for adjusting the physical properties of recorded materials, polyurethane resins, vinyl resins, acrylic resins, rubber resins, and waxes as necessary. it can.

  When a coloring material is used for the radiation curable clear ink composition, a dye is desirable to ensure light transmission. Examples of the dye include various dyes that are usually used in inkjet recording, such as direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes, vat dyes, and soluble vat dyes. By blending the dye, the third dot group can be colored, and color can be imparted to the gloss of the metallic glossy surface.

  The method of attaching the radiation curable clear ink composition is the same as the method described in the section “1.2.1. Method of attaching the glossy ink composition”, and thus the description thereof is omitted.

  The third dot group is formed to protect, polish, or color the surface of the recorded material to be formed. Accordingly, the radiation curable clear ink composition is deposited on at least one of the recording medium, the first dot group, and the second dot group.

  The step of hardening the third dot group is the same as “1.3. Step of hardening the first dot group”, and thus the description thereof is omitted.

1.7. Effects According to the recording method as described above, the surface pattern (for example, uneven shape) of the metallic gloss surface can be controlled by controlling the surface pattern (for example, uneven shape) of the first dot group. Furthermore, since the pattern on the surface of the first dot group can be continuously changed according to the amount of the ink composition attached, the pattern on the metallic gloss surface can also be changed continuously. Therefore, according to the recording method of the present invention, the variation of the specular glossiness of the metallic glossy surface can be very easily formed by adjusting the amount of the ink composition used when forming the first dot group. Thus, according to the recording method of the present invention, it is possible to easily form a plurality of metallic glossy surfaces having different specular glossiness on one recording surface.

  Furthermore, according to the recording method of the present invention, for example, it is easy to add the first dot group and the second dot group to an existing document and make the document difficult to copy. Easy. The recording method of the present invention can easily form a metallic glossy surface having a different specular glossiness in the metallic glossy surface, and can provide a recorded matter that is difficult to be copied / reproduced. Can be protected, making it difficult to copy and duplicate.

2. Recorded matter The recorded matter according to the present invention is formed by the recording method described above. Therefore, information can be recorded on the recording surface of the recording medium by a plurality of metallic glossy surfaces having different specular glossiness. For this reason, such recorded matter has a property that it is very difficult to copy / reproduce using optical detection means such as a copy. Moreover, such a recorded matter has a feature that the recorded information can be read by visual observation.

3. Identification method 3.1. First Embodiment An identification method according to the present embodiment is the above-described method for identifying a recorded matter. The identification method according to the present embodiment is a method for identifying the recorded matter described above, and observes the particle shape of the color material composed of tabular particles contained in the glossy ink composition forming the second dot group with a microscope. The authenticity of the recorded matter is determined based on the suitability of the particle shape of the color material composed of tabular grains observed through a microscope.

  The recorded matter described above has a second dot group formed by the glossy ink composition. Therefore, the second dot group contains a color material composed of tabular grains having a characteristic shape. As described above, the color material composed of tabular grains of the glossy ink composition is tabular grains, and when the major axis on the plane of the tabular grains is X, the minor axis is Y, and the thickness is Z, the tabular grains The 50% average particle diameter R50 of the equivalent circle diameter determined from the area of the XY plane of the particle-like particles is 0.5 to 3 μm and satisfies the condition of R50 / Z> 5. Therefore, by observing the second dot group with a microscope, it is possible to easily confirm the shape of the color material composed of tabular grains. Examples of the microscope include, for example, various microscopes, stereo microscopes, fluorescence microscopes, laser scanning microscopes, confocal laser microscopes and other optical microscopes, scanning electron microscopes (SEM), transmission electron microscopes (TEM) and other electron microscopes, SPM, Examples thereof include a scanning probe microscope such as AFM.

  Thereby, since it can be determined whether or not the recorded matter is recorded by the above-described recording method, the recorded matter can be identified and the authenticity of the recorded matter can be determined.

3.2. Second Embodiment An identification method according to the present embodiment is a method for identifying a recorded matter as described above, wherein the second dot group contains an identification substance, and includes a step of observing the second dot group with a microscope. Then, the authenticity of the recorded matter is determined by the content of the identification substance observed with a microscope.

  The recorded matter of this embodiment uses a glossy ink composition containing an identification substance in the step of forming the second dot group. Therefore, the second dot group is formed in a state where the identification substance is included. By observing this second dot group with a microscope, the content of the substance for identification can be easily confirmed. Examples of the microscope include various optical microscopes, scanning electron microscopes, and transmission electron microscopes.

  It is preferable to use a substance having characteristics in terms of shape and physical properties as the identification substance. For example, a standard particle with excellent sphericity and close to monodisperse particle size distribution can be used only for special purposes such as calibration of measuring instruments. Since it does not adhere, authenticity can be easily determined by observation with an optical microscope. Moreover, if it is a fluorescent particle, the property which absorbs the light of a specific wavelength and discharge | releases the light of the wavelength shifted by Stokes shift can be utilized, and this also becomes possible to determine authenticity easily.

  In particular, when the observation is performed using the laser microscope, the pigment particles and the identification substance can be easily observed. Examples of standard particles include 8000,9000 series particle size standard particles manufactured by Moritex Corporation, Tospearl 120, 130 manufactured by Momentive Performance Technologies, Inc., and the like. Examples of the fluorescent particles include fluorescent particle blue and green manufactured by Moritex Corporation.

  Thereby, since it can be determined whether or not the recorded matter is recorded by the above-described recording method, the recorded matter can be identified and the authenticity of the recorded matter can be determined.

  The discriminating substance is preferably added in a range that does not affect observation with the naked eye and that can be easily discriminated by an observation instrument.

4). Examples Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

4.1. Preparation of samples for evaluation of specular gloss and surface pattern 4.1.1. Formation of first dot group A white vinyl chloride sheet (SPVC-G-1270T manufactured by Roland DG Co., Ltd.) was prepared as a recording medium. A radiation curable ink composition was printed on the sheet using an ink jet recording apparatus (PX-7500, manufactured by Seiko Epson Corporation). As the printing pattern, a solid pattern having a width of 10 cm and a length of 2 m was adopted. The radiation curable ink composition used was ethylene glycol monoallyl ether = 71.6 mass% and biscoat # 1000 = 20.0 mass% as a polymerizable compound, and Irgacure 819 = 6.4 mass as a photopolymerization initiator. %, And Irgacure 127 = 1.6% by mass, and the additive used was BYK-UV3500 = 0.2% by mass and IrgastabUV-10 = 0.2% by mass. After printing the solid pattern, the solid pattern was irradiated with ultraviolet rays by an ultraviolet irradiation light source so that the integrated light amount at a wavelength of 365 nm was 400 mJ / cm ² . At this time, a plurality of solid patterns having different amounts (mg / cm ² ) of radiation curable ink composition were formed. As a result, a first dot group having a different surface pattern was formed on the recording medium.

4.1.2. Formation of second dot group Next, a glossy ink composition was printed on the solid pattern (first dot group) using an ink jet recording apparatus (SP-300V manufactured by Roland DG Co., Ltd.). The glossy ink composition used was diethylene glycol diethyl ether (manufactured by Nippon Emulsifier Co., Ltd.) = 63.8% by mass, γ-butyrolactone (manufactured by Kanto Chemical Co., Ltd.) = 15% by mass, tetraethylene glycol dimethyl ether (Japan) as the organic solvent. Emulsifier Co., Ltd.) = 18% by mass, as resin, N-2043-60MEX (manufactured by Harima Chemicals Co., Ltd.) = 2% by mass, and surfactant, BYK-UV3500, (manufactured by Big Chemie Japan Co., Ltd.) = 0. 2% by mass, a metal pigment containing 1% by mass of metal powder having the characteristics of R50 = 0.89 μm, average film thickness (Z) = 0.02 μm, R50 / Z = 44.5 as solid content Used. As a result, the second dot group was formed on the first dot group having a different surface pattern.

The thickness of the second dot group was uniform over the entire area, the discharge amount of the glossy ink composition was 1.1 mg / cm ^2, and the weight after drying was 11 μg / cm ² .

  In addition, the metal powder used in the present Example was manufactured as follows. First, on a PET film having a film thickness of 100 μm, it is composed of 3% by mass of cellulose acetate butyrate (butylation rate of 35 to 39%, manufactured by Kanto Chemical Co., Ltd.) and 97% by mass of diethylene glycol diethyl ether (manufactured by Nippon Emulsifier Co., Ltd.). The resin layer coating solution was uniformly applied by a bar coating method and dried at 60 ° C. for 10 minutes to form a resin thin film layer on the PET film.

  Next, an aluminum vapor deposition layer having an average film thickness of 20 nm was formed on the resin layer using a vacuum vapor deposition apparatus (VE-1010 manufactured by Vacuum Device Corporation).

  Next, the above laminate was ultrasonically dispersed in diethylene glycol diethyl ether. The ultrasonic dispersion was performed using an ultrasonic disperser VS-150 manufactured by AS ONE Corporation. The processing time was 12 hours. At this time, the aluminum vapor deposition layer was peeled off from the resin thin film layer and refined. The obtained dispersion was filtered with a SUS mesh filter having an opening of 5 μm to remove coarse particles. Next, purification with a solvent was performed to obtain a metal powder having the above characteristics.

4.2. Preparation of copy / visibility evaluation sample 4.2.1. Formation of first dot group As a recording medium, an A4 transparent PET film (trade name: XEROX FILM <no frame>: manufactured by Fuji Xerox Co., Ltd.) was prepared. A radiation curable ink composition was printed on the film using an inkjet recording apparatus (PX-7500, manufactured by Seiko Epson Corporation). As the printing pattern, a solid pattern with a width of 4 cm × 4 cm was adopted. The radiation-curable ink composition used was the same as described in “4.1. Preparation of specular gloss and surface pattern measurement sample”. After printing the solid pattern, the solid pattern was irradiated with ultraviolet rays by an ultraviolet irradiation light source so that the integrated light amount at a wavelength of 365 nm was 400 mJ / cm ² . At this time, a plurality of solid patterns having different amounts (mg / cm ² ) of radiation curable ink composition were formed. Specifically, the amount of use is changed by 10 (mg / cm ² ) in increments of 10 (mg / cm ² ) from 20 (mg / cm ² ) to 100 (mg / cm ² ), so that the first dots having nine different surface patterns on the recording medium Groups were formed. In this manner, two printed materials 1000 and 2000 were produced under the same conditions.

4.2.2. Formation of second dot group Next, a glossy ink composition using an ink jet recording apparatus (SP-300V manufactured by Roland DG Co., Ltd.) on each of the nine solid patterns (first dot group) of the printed matter 1000 and the printed matter 2000. Printed. The second dot group was formed in the same manner as in “4.1.2. Formation of second dot group” on the two printed materials.

4.2.3. Formation of third dot group Next, the third dot group was formed on the printed material 2000 on which the second dot group was formed. In the third dot group, the radiation curable ink composition and the curing treatment conditions were set to “4.1. Preparation of a sample for measurement of specular gloss and surface pattern” on nine solid patterns (first dot group) of the printed material 2000. It was formed in the same manner as described above.

4.3. Evaluation of specular gloss and surface pattern 4.3.1. Evaluation of specular gloss The specular gloss of the surface of the recorded material (second dot group) was measured according to Japanese Industrial Standard (JIS) Z8741: 1997. The apparatus used is Nippon Denshoku Industries Co., Ltd. GlossMeter model number VGP5000. The results are plotted in FIG. 2 for 20 ° specular gloss and 60 ° specular gloss at different parts of the surface pattern of the recorded matter.

4.3.2. Evaluation of surface pattern of recorded matter The surface pattern of the recorded matter (the shape of the surface of the second dot group) was measured by a surface shape measuring device (Laser Scanning Microscope VK-9700, manufactured by Keyence Corporation), and the contour curve obtained. Evaluated by. The arithmetic mean roughness Ra of the contour curve of each solid pattern was determined using the same apparatus. In FIG. 2, the arithmetic average roughness Ra (%) is plotted against the ink usage (mg / cm ² ).

4.3.3. Evaluation Result of Specular Gloss and Surface Pattern As seen in FIG. 2, the second dot group had a surface pattern reflecting the surface pattern of the first dot group. As a result, it was found that the pattern of the metallic gloss surface can be controlled by controlling the pattern of the surface of the first dot group. Furthermore, since the Ra value of the pattern on the surface of the first dot group can be continuously changed depending on the amount of radiation-cured ink composition attached, the Ra value of the pattern on the metallic glossy surface can also be changed continuously. I understood that I could do it.

  Further, as seen in FIG. 2, there is a correlation between the Ra value of the surface pattern of the second dot group and the specular gloss value, and when the Ra value of the surface pattern of the second dot group increases, It was found that the specular gloss value (both 20 ° and 60 °) was small. In addition, since the Ra value of the pattern on the surface of the second dot group can be continuously changed, it has been found that the specular gloss value can also be arbitrarily changed continuously.

  From the above, it has been found that the specular gloss value of the recorded material can be widely changed based on the pattern of the surface of the first dot group. Further, as apparent from the above examples, the variation of the specular glossiness of the metallic glossy surface is very easy depending on the amount of the radiation curable ink composition used when forming the first dot group by the ink jet recording apparatus. It turns out that it can be achieved. Therefore, according to such a method, it can be seen that a plurality of metallic glossy surfaces having different specular glossiness can be easily formed on one recording surface.

4.4. 3. Evaluation of Copyability / Visibility FIG. 3 shows a printed product 1000 which is not formed with the third dot group out of the “4.2. Sample for Evaluation of Copying / Visibility and Friction” described above. The result of copying with (Document X650I manufactured by Fuji Xerox Co., Ltd.) is shown. In the figure, the part denoted by reference numeral 0 is an area where no dot group is formed, and the rectangular area denoted by reference numerals 20 to 100 is a radiation curable ink composition when forming the first dot group. usage of 20 (mg / cm ²⁾ from 100 (mg / cm ²⁾ to 10 (mg / cm ²⁾ is an area which has changed by, are filled by matching the code and usage. When the area | region in which the 2nd dot group of the printed matter 1000 and the printed matter 2000 was formed was observed with the naked eye, all had metallic luster.

  From this example, it was found that a metallic glossy surface having an arbitrary specular glossiness can be easily formed on the same recording surface of one recording medium.

Referring to FIG. 3, it was found that the metallic luster was not reproduced by copying in any of the print areas, and the printed material 1000 could not be copied by the copying machine. Furthermore, in the area | region (20-60) where the usage-amount of the radiation curable ink composition at the time of forming a 1st dot group is 60 (mg / cm < ² >) or less, although it has a 2nd dot group, It has been found that the result of copying is indistinguishable from an unprinted area. That is, in these areas, it was found that the recording information formed by the metallic glossy surface, which can be easily read by visual observation, cannot be copied by the copying machine. Moreover, when the same evaluation was performed on the printed matter 2000, the same result was obtained.

  In addition, an attempt was made to capture an image using a scanner for printed matter 1000 and printed matter 2000 (using the scanner function of PM-A970 manufactured by Seiko Epson Corporation). Despite the fact that the gloss can be easily recognized, it was found that the captured data was recognized as black to gray, and it was impossible to reproduce the metallic luster from the obtained image data.

  For these reasons, the recorded matter (printed matter 1000 and printed matter 2000) of the example is very difficult to read optically even if it is a metallic glossy surface that can be easily read by the naked eye. I understand that I can't.

  Further, in the recorded matter of the present embodiment, if information is recorded by a metallic glossy surface having a different specular glossiness, the information cannot be read by an optical method even though the information can be read by the naked eye, In other words, it has been found that information that is difficult to copy and duplicate can be realized.

  The present invention is not limited to the above-described embodiments, and various modifications can be made. For example, the present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations that have the same functions, methods, and results, or configurations that have the same purposes and effects). In addition, the invention includes a configuration in which a non-essential part of the configuration described in the embodiment is replaced. In addition, the present invention includes a configuration that achieves the same effect as the configuration described in the embodiment or a configuration that can achieve the same object. In addition, the invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

1000 printed matter

Claims (17)

Forming a first dot group by ejecting droplets of an ink composition using an inkjet recording apparatus and attaching the droplets onto a recording medium;
A step of forming a second dot group by adhering a glossy ink composition containing a colorant composed of tabular particles on at least the first dot group;
Only including,
The first dot group is formed to have a pattern on the surface,
A step of forming the first dot group and a step of forming the second dot group form a metallic glossy surface having a predetermined specular glossiness,
A pattern is formed on the surface with an ink usage different from the step of forming the first dot group by ejecting droplets of the ink composition using an ink jet recording apparatus and attaching the liquid onto the recording medium. A step of forming a first dot group, and a step of forming a second dot group by adhering a glossy ink composition containing a color material composed of tabular particles on at least the first dot group. A recording method of forming another metallic glossy surface having a specular glossiness different from the predetermined specular glossiness . In claim 1,
The recording method, wherein the pattern is controlled by an adhesion amount of the droplet of the ink composition in the step of forming the first dot group. In claim 1 or claim 2 ,
The recording method, wherein the color material comprising the tabular grains is at least one of a metal pigment and a pearl pigment. In claim 3 ,
The recording method, wherein the metal pigment is made of aluminum or an aluminum alloy. In claim 3 or claim 4 ,
The recording method according to claim 1, wherein the structure of the metal pigment or pearl pigment is a tabular grain formed from a multilayer of thin films. In any one of Claims 1 thru | or 5 ,
The step of forming the first dot group is a recording method performed using a radiation curable ink composition. In any one of Claims 1 thru | or 6 ,
The recording method , wherein the pattern is formed by a step of irradiating the first dot group with radiation and performing a curing process after the step of forming the first dot group. In claim 7 ,
The step of irradiating the first dot group with radiation and performing the curing process is performed by irradiating light having a wavelength of 350 nm to 450 nm. In any one of Claims 1 thru | or 8 ,
The step of forming the second dot group is performed by ejecting a droplet of the glossy ink composition using the inkjet recording apparatus and attaching the droplet onto at least the first dot group. Recording method. In any one of Claims 1 thru | or 9 ,
After the step of forming the second dot group, a step of forming a third dot group by further attaching a radiation curable clear ink composition;
Irradiating the third dot group with radiation and performing a curing treatment;
Including a recording method. In claim 10 ,
The step of irradiating the third dot group with radiation and performing the curing process is performed by irradiating light having a wavelength of 350 nm to 450 nm. In any one of Claims 1 thru | or 11 ,
When the major axis on the plane of the colorant composed of tabular grains is X, the minor axis is Y, and the thickness is Z, the 50% average particle diameter R50 in the equivalent circle diameter determined from the area of the XY plane of the tabular grains. Is a recording method in which 0.5 to 3 μm and the condition of R50 / Z> 5 is satisfied. A recorded matter in which information is recorded by the recording method according to any one of claims 1 to 12 . Used for the recording method according to any one of claims 1 to 12, the ink jet recording apparatus. The method for identifying recorded matter according to claim 13 ,
A step of observing with a microscope the particle shape of the color material composed of the tabular particles contained in the glossy ink composition forming the second dot group;
An identification method in which the authenticity of the recorded matter is determined based on the suitability of the particle shape of the colorant composed of the tabular grains observed with the microscope. The method for identifying recorded matter according to claim 13 ,
The second dot group contains a substance for identification,
Observing the second dot group with a microscope,
An identification method for determining the authenticity of the recorded matter based on the content of the identification substance observed with the microscope. In claim 16 ,
The identification method, wherein the identification substance is at least one selected from transparent particles, colored particles, and fluorescent substances.