JP2021054013A - Liquid discharge device, ink set and image formation method - Google Patents

Abstract

To provide a liquid discharge device which can achieve both of the excellent metallic glossiness and the scratch resistance when performing the decorative printing using metallic ink.SOLUTION: There is provided a liquid discharge device in which a chromatic ink discharge nozzle array in which nozzles discharging chromatic ink are arrayed, an achromatic ink discharge nozzle array in which nozzles discharging achromatic ink containing a resin are arrayed and a metallic ink discharge nozzle array in which nozzles discharging metallic ink containing an organic solvent are arrayed are arranged side by side in one or a plurality of heads, and which discharges the chromatic ink onto a recording medium, discharges the achromatic ink to a region to which the metallic ink is to be discharged, and discharges the metallic ink to a region to which the achromatic ink is discharged.SELECTED DRAWING: Figure 3

Description

The present invention relates to a liquid ejection device, an ink set and an image forming method.

The inkjet recording method is a recording method in which ink droplets are directly ejected from a very fine nozzle onto a recording medium and adhered to obtain characters or images. According to this method, not only the noise of the device to be used is low and the operability is good, but also the colorization is easy and plain paper can be used as a recording medium. , Widely used as an output machine in offices and homes. Even in industrial applications, it is expected to be used as an output machine for digital printing due to the improvement of inkjet technology, and printing machines capable of printing on non-absorbent base materials using solvent ink or UV ink have actually been put on the market. It was. Furthermore, with the introduction of metallic ink, inkjet technology has been developed not only for printing characters and patterns, but also for decorative printing with metallic luster.

For example, Patent Document 1 describes an inkjet recording method in which an ink using a metallic pigment and a chromatic color ink are used in combination.
Further, Patent Document 2 describes a method of imparting gloss by overcoating.

However, in order to obtain sufficient metallic luster using metallic ink, the surface of the metallic ink adhesion portion must be sufficiently smooth, and the surface of the metallic ink adhesion portion must be covered with the metallic ink without any gaps. It is necessary to achieve both. This makes it difficult for the metallic ink to contain a sufficient amount of the fixing resin. When the amount of fixing resin contained in the metallic ink is large, no matter how uniform the image is formed, a portion having a large amount of fixing resin and a portion having a large amount of metallic ink are generated on the image surface. As a result, unevenness is generated on the image surface, and a non-adhered portion of the metallic ink is generated, so that the glossiness is lowered. However, if the amount of the fixing resin contained in the metallic ink is simply reduced, the scratch resistance of the image is lowered, and the metallic ink is peeled off even if it is rubbed a little.

Further, when the decorative printing is performed on the already formed image instead of the printing using only the metallic ink, the decrease in glossiness becomes more remarkable. Even on a relatively smooth base material such as vinyl chloride or polyethylene terephthalate (PET), the portion where the image is formed by the chromatic ink has irregularities due to the pigment or the fixing resin. This unevenness is caused by uneven distribution of chemical materials, and is caused even in an image formed from one drop of ink. Therefore, even if the amount of adhesion or the like is controlled to be ejected, it cannot be eliminated. When an image with metallic ink is formed on the image, the surface unevenness of the underlying chromatic ink image becomes a direct factor of reducing the metallic luster.

Further, as described above, Patent Document 1 describes an inkjet recording method in which an ink using a metallic pigment and a chromatic color ink are used in combination. For example, a form in which a chromatic ink image is formed on top of forming an image using a metallic pigment is described. However, this form does not solve the problem of reduced metallic luster that occurs when a metallic image is decoratively printed on a chromatic ink image.
Further, Patent Document 2 describes a method of imparting gloss by overcoating, and it is known that the glossiness is increased by overcoating. However, what is required for metallic printing is not mere gloss but metallic luster due to specular reflection. Sufficient metallic luster cannot be obtained unless the metallic pigment portion before overcoating is smooth and defect-free.

As described above, it has been a very difficult problem in the industry to achieve both metallic luster and abrasion resistance when performing decorative printing using metallic ink.

Therefore, an object of the present invention is to provide a liquid ejection device capable of achieving both excellent metallic luster and abrasion resistance when performing decorative printing using metallic ink.

The above problem is solved by the following configuration 1).
1) A row of chromatic ink ejection nozzles in which nozzles for ejecting chromatic ink are arranged, and
A row of achromatic ink ejection nozzles in which nozzles for ejecting achromatic ink containing resin are arranged,
A row of metallic ink ejection nozzles in which nozzles for ejecting metallic ink containing an organic solvent are arranged is arranged side by side on one or a plurality of heads.
After ejecting the chromatic ink onto the recording medium,
The achromatic ink is discharged into the area where the metallic ink is discharged, and the achromatic ink is discharged.
A liquid ejection device characterized in that the metallic ink is ejected to a region where the achromatic ink is ejected.

According to the present invention, there is provided a liquid ejection device capable of achieving both excellent metallic luster and abrasion resistance when performing decorative printing using metallic ink.

It is a perspective explanatory drawing which shows an example of an inkjet recording apparatus. It is a perspective explanatory view which shows an example of the main tank in an inkjet recording apparatus. (A) is a plan view for explaining the liquid discharge device of this invention, and (b) is a figure for showing the form in which an ink set is loaded in the discharge head. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a figure for demonstrating the embodiment of the arrangement of each nozzle row in the liquid discharge apparatus of this invention. It is a block diagram of an example of the liquid discharge device of this invention. It is a flowchart of image formation in this invention. It is sectional drawing of the image formed by the liquid discharge device of this invention.

Hereinafter, embodiments of the present invention will be described in more detail.
As a result of diligent studies by the present inventors in order to solve the above-mentioned problems, the detailed reason is unknown, but by ejecting the metallic ink onto the achromatic ink, the achromatic ink contains a resin, and the metallic ink is produced. By containing an organic solvent, unevenness due to uneven distribution of the resin and pigment of the chromatic color ink that is the base is reduced by coating with clear ink with less uneven distribution of solid content, and the smoothness required as a base of metallic ink is reduced. It is possible to ensure the property and develop a sufficient metallic luster of the metallic ink. In addition, since the metallic ink contains an organic solvent, the resin of the achromatic ink that is the base can be dissolved and the metallic ink can be fixed well, even if the metallic ink does not contain the fixing resin or a small amount. Even so, good abrasion resistance can be provided.
The glossiness can also be improved by dissolving the resin on the surface of the clear ink image with the organic solvent of the metallic ink to make it smoother.
Further, in the preferred embodiment of the present invention, since the organic solvent contained in the metallic ink is an ether solvent, the unevenness of the chromatic color ink can be further reduced, and a more excellent metallic luster can be exhibited.

(Colored ink)
First, chromatic color ink (hereinafter, may be referred to as color ink) will be described.

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

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

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

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

The content of the organic solvent in the ink is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of ink drying property and ejection reliability, 30% by mass or more and 95% by mass or less is preferable. More preferably, it is 40% by mass or more and 90% by mass or less.

<Water>
The content of water in the ink is not particularly limited and can be appropriately selected depending on the intended purpose.

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

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

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

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

<Resin>
The type of resin contained in the ink is not particularly limited and may be appropriately selected depending on the intended purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, etc. Examples thereof include resins, styrene-butadiene resins, vinyl chloride resins, acrylic styrene resins, and acrylic silicone resins.
Resin particles made of these resins may be used. It is possible to obtain ink by mixing resin particles with a material such as a coloring material or an organic solvent in the state of a resin emulsion in which water is dispersed as a dispersion medium. As the resin particles, those synthesized as appropriate may be used, or commercially available products may be used. Further, these may be used alone or in combination of two or more kinds of resin particles.

The volume average particle diameter of the resin particles is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of obtaining good fixability and high image hardness, 10 nm or more and 1,000 nm or less are preferable. More than 200 nm is more preferable, and 10 nm or more and 100 nm or less is particularly preferable.
The volume average particle size can be measured using, for example, a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

The content of the resin is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of fixability and storage stability of the ink, 0.5% by mass or more based on the total amount of the ink is 10% or more. It is preferably 1% by mass or less, and more preferably 1% by mass or more and 5% by mass or less.

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

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

<Surfactant>
As the surfactant, any of a silicone-based surfactant, a fluorine-based surfactant, an amphoteric surfactant, a nonionic surfactant, and an anionic surfactant can be used.
The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, single-ended modified polydimethylsiloxane, and side chain double-ended modified polydimethylsiloxane. Those having an oxyethylene group and a polyoxyethylene polyoxypropylene group are particularly preferable because they exhibit good properties as an aqueous surfactant. Further, as the silicone-based surfactant, a polyether-modified silicone-based surfactant can also be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the Si portion side chain of dimethylsiloxane.
Examples of the fluorine-based surfactant include a perfluoroalkyl sulfonic acid compound, a perfluoroalkyl carboxylic acid compound, a perfluoroalkyl phosphate compound, a perfluoroalkyl ethylene oxide adduct, and a perfluoroalkyl ether group in the side chain. A polyoxyalkylene ether polymer compound is particularly preferable because it has a low foaming property. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid and perfluoroalkyl sulfonic acid salt. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylic acid salt. The polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain includes a sulfate ester salt of a polyoxyalkylene ether polymer having a perfluoroalkyl ether group in the side chain and a perfluoroalkyl ether group in the side chain. Examples thereof include salts of polyoxyalkylene ether polymers. The counterions of the salts in these fluorine-based surfactants are Li, Na, K, NH ₄ , NH ₃ CH ₂ CH ₂ OH, NH ₂ (CH ₂ CH ₂ OH) ₂ , NH (CH ₂ CH ₂ OH). _3rd grade can be mentioned.
Examples of the amphoteric tenside agent include laurylaminopropionate, lauryldimethylbetaine, stearyldimethylbetaine, and lauryldihydroxyethylbetaine.
Examples of the nonionic surfactant include polyoxyethylene alkyl phenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkyl amine, polyoxyethylene alkyl amide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, and polyoxyethylene sorbitan. Examples thereof include a fatty acid ester and an ethylene oxide adduct of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, lauryl salt, and polyoxyethylene alkyl ether sulfate salt.
These may be used alone or in combination of two or more.

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

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

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

In the compound represented by the general formula (F-1), m is preferably an integer of 0 to 10, and n is preferably an integer of 0 to 40 in order to impart water solubility.
General formula (F-2)
C _n F _{2n + 1-} CH ₂ CH (OH) CH ₂ −O− (CH ₂ CH ₂ O) _a− Y
In the compound represented by the above general formula (F-2), Y is H or CmF _{2m + 1} and m is an integer of 1 to 6, or CH ₂ CH (OH) CH _2- CmF _{2m + 1} and m is 4 to 6. It is an integer, or CpH _{2p + 1} and p is an integer of 1-19. n is an integer of 1-6. a is an integer of 4 to 14.
Commercially available products may be used as the above-mentioned fluorine-based surfactant. Examples of this commercially available product include Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, and S-145 (all manufactured by Asahi Glass Co., Ltd.); Full Lard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Co., Ltd.); Megafuck F-470, F -1405, F-474 (all manufactured by Dainippon Ink and Chemicals Co., Ltd.); Zonyl TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, UR, Capstone FS-30, FS-31, FS-3100, FS-34, FS-35 (all manufactured by The Chemours Company); FT-110, FT-250, FT-251, FT-400S, FT-150, FT- 400SW (all manufactured by Neos Co., Ltd.), Polyfox PF-136A, PF-156A, PF-151N, PF-154, PF-159 (manufactured by Omniova), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.) Among these, FS-3100, FS-34, FS- of The Chemours Co., Ltd., from the viewpoint of remarkably improving good print quality, particularly color development, penetrability to paper, wettability, and leveling property. 300, FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Co., Ltd., Polyfox PF-151N manufactured by Omniova Co., Ltd. and Unidyne DSN-manufactured by Daikin Industries Co., Ltd. 403N is particularly preferable.

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

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

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

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

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

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

(Achromatic ink)
Next, achromatic ink (hereinafter, may be referred to as clear ink) will be described.
The achromatic ink referred to in the present invention refers to an ink that does not contain a coloring material.
The achromatic ink used in the present invention can contain the organic solvent, water, resin, and additives described in the chromatic ink, except that it does not contain a coloring material, except for the forms shown below. The preferred range is also the same.

The resin used for the achromatic ink used in the present invention is preferably a urethane resin, an acrylic resin, a vinyl acetate resin or the like from the viewpoint of improving the effect of the present invention.
The resin in the achromatic ink is preferably 1% by mass or more and 30% by mass or less, and more preferably 1% by mass or more and 15% by mass or less, based on the total amount of the achromatic ink, from the viewpoint of fixability of the metallic ink.
The content of the organic solvent in the achromatic ink is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of improving the effect of the present invention, it is 30% by mass or more and 99.8% by mass or less. Is preferable, and 40% by mass or more and 99.5% by mass or less is more preferable.

(Metallic ink)
Next, the metallic ink will be described.
The metallic ink referred to in the present invention refers to an ink that imparts metallic luster to an image.
The metallic ink used in the present invention can contain the organic solvent, water, resin, and additive described in the chromatic color ink, except that the metallic ink contains a coloring material for metallic ink as a coloring material. Except for the forms shown, the preferred range is also the same. The metallic ink used in the present invention contains an organic solvent.

<Color material for metallic ink>
The color material for metallic ink is preferably a pigment, and when it is in the form of scales, the 50% average particle diameter R50 of the equivalent circle diameter obtained from the area of the plane is 0.4 μm to 3 μm, and when it is in the form of particles. The average particle size is preferably 0.05 μm to 0.4 μm. Within this range, a natural silver metallic luster can be obtained.
The particle size of the color material for metallic ink can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack Bell Co., Ltd.).

As the pigment, for example, a simple substance of a metal, an alloy, or a fine powder obtained by finely pulverizing a metal compound can be used. More specifically, one or more of a group of simple metals consisting of aluminum, silver, gold, nickel, chromium, tin, zinc, indium, titanium, silicon, copper, or platinum, or any of these. Examples thereof include alloys obtained by combining a group of metals, or those obtained by finely pulverizing any one or more of the oxides, nitrides, sulfides, and carbides of these groups of metals alone or alloys. .. Of these, pigments containing aluminum are preferable. Aluminum pigments have high flatness and can obtain high metallic luster, but because they are flat plates, they have a small contact area and are inferior in fixability. Therefore, by using the present invention, both gloss and scratch resistance can be achieved. It is preferable because it becomes possible.

The content of the coloring material in the metallic ink is preferably 0.1% by mass or more and 15% by mass or less, more preferably 1% by mass or more and 10% by mass, from the viewpoint of improving the image density, good fixability and ejection stability. % Or less.
In order to disperse the pigment to obtain an ink, a method of introducing a hydrophilic functional group into the pigment to obtain a self-dispersing pigment, a method of coating the surface of the pigment with a resin and dispersing it, and a method of dispersing using a dispersant are used. The method, etc. can be mentioned.

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

<Pigment dispersion for metallic ink>
It is possible to obtain an ink by mixing a material such as an organic solvent with a pigment. It is also possible to produce an ink by mixing a material such as water or an organic solvent with a pigment dispersion obtained by mixing a pigment and other dispersants.
The pigment dispersion is obtained by mixing and dispersing a pigment, a pigment dispersant, water, an organic solvent, and other components as necessary, and adjusting the particle size. It is preferable to use a disperser for dispersion. The particle size of the pigment in the pigment dispersion is not particularly limited, but it is scaly as described above because the dispersion stability of the pigment is good and the image quality such as ejection stability and image density is also high. In this case, the 50% average particle size R50 of the equivalent circle diameter obtained from the area of the plane is 0.4 μm to 3 μm, and when it is in the form of particles, the average particle size is preferably 0.05 μm to 0.4 μm. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).
The content of the pigment in the pigment dispersion is not particularly limited and may be appropriately selected depending on the intended purpose. However, from the viewpoint of obtaining good ejection stability and increasing the image density, 0.1 mass is used. % Or more and 50% by mass or less are preferable, and 0.1% by mass or more and 30% by mass or less are more preferable. If necessary, the pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifuge, or the like.

The resin used for the metallic ink used in the present invention is preferably a urethane resin, an acrylic resin, a vinyl acetate resin or the like from the viewpoint of improving the effect of the present invention.
The content of the resin in the metallic ink is preferably 5% by mass or less, more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less, based on the total amount of the metallic ink, from the viewpoint of metallic luster. If the content of the resin in the metallic ink exceeds 5% by mass, sufficient metallic luster may not be exhibited.

Further, the metallic ink used in the present invention preferably contains an ether solvent as an organic solvent. According to this form, it is considered that the resin in the achromatic ink can be plasticized to further reduce the unevenness of the chromatic ink, and a more excellent metallic luster can be exhibited. Further, a high effect can be obtained even when the amount of resin in the clear ink is small. Examples of the ether solvent include ethers described in the section of chromatic ink, and glycol ether compounds are preferable.
In addition, according to the principle of exhibiting the effect of the present invention, since the metallic ink contains a large amount of an organic solvent, the resin of the clear ink is efficiently dissolved and the effect is improved. Therefore, it is preferable to use aluminum stable in the organic solvent as the pigment. ..

Further, the metallic ink may contain a plasticizer. By melting the resin in the clear ink with a plasticizer, the effect of the present invention can be further enhanced.
The plasticizer is preferably at least one compound selected from the group consisting of phosphate esters, phthalates, aliphatic polybasic acids, trimellitic acid esters, acetic acid esters and ricinoleic acid esters.
As the phosphoric acid ester, known ones can be used. Specific examples thereof include tris (2-ethylhexyl) phosphate, trimethyl phosphate, triethyl phosphate, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyldiphenyl phosphate, 2-ethylhexyl diphenyl phosphate and the like. ..
As the phthalate ester, known ones can be used. Specific examples thereof include bis (2-ethylhexyl) phthalate, dimethylphthalate, diethylphthalate, dibutylphthalate, diisodecylphthalate, butylbenzylphthalate, diisononylphthalate, ethylphthalylethylglycolate and the like.
As the aliphatic polybasic acid ester, known ones can be used. Specific examples thereof include aliphatic dibasic acid esters such as adipate ester, azelaic acid ester, sebacic acid ester, maleic acid ester, and fumaric acid ester.
As the trimellitic acid ester, known ones can be used. Specifically, tri-2-ethylhexyl trimerite, tri-n-octyl trimerite, tridecyl trimerite, triisodecyl trimerite, di-n-octyl-n-decyl trimerite, etc. Can be mentioned.
As the acetic acid ester, known ones can be used. Specific examples thereof include glyceryl triacetate, 2-ethylhexyl acetate, polyglycerin acetate having a degree of polymerization of polyglycerin of 2 to 4, and an acetylation rate of 50 to 100%.
Examples of the ricinoleic acid ester include known ricinoleic acid ester-based plasticizers such as alkyl acetyl ricinolate (alkyl group: 1 to 10 carbon atoms) such as methyl acetyl ricinolate and butyl acetyl ricinolate.
The content of the plasticizer in the metallic ink is preferably, for example, 0.5% by mass to 5% by mass.

<Recording medium>
The recording medium is not particularly limited, and plain paper, glossy paper, special paper, cloth, or the like can be used, but good image formation can be achieved even if a non-permeable base material is used.
The non-permeable base material is a base material having a surface having low water permeability and low absorbency, and includes a material that does not open to the outside even if there are many cavities inside, and more quantitatively. , A substrate having a water absorption amount of 10 mL / m ² or less from the start of contact to 30 msec ^{1/2 in the Bristow method.}
As the non-permeable base material, for example, a plastic film such as a vinyl chloride resin film, a polyethylene terephthalate (PET) film, polypropylene, polyethylene, or a polycarbonate film can be preferably used.

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

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

<Recording device, recording method>
The ink of the present invention can be suitably used for various recording devices by an inkjet recording method, for example, a printer, a facsimile device, a copying device, a printer / fax / copier multifunction device, a three-dimensional modeling device, and the like.
In the present invention, the recording device and the recording method are devices capable of ejecting ink, various processing liquids, and the like to a recording medium, and a method of recording using the device. The recording medium means a medium to which ink and various treatment liquids can adhere even temporarily.
This recording device can include not only a head portion for ejecting ink, but also means related to feeding, transporting, and discharging paper of a recording medium, and other devices called pretreatment devices and posttreatment devices. ..
The recording device and recording method may include a heating means used in the heating step and a drying means used in the drying step. The heating means and the drying means include, for example, means for heating and drying the print surface and the back surface of the recording medium. The heating means and the drying means are not particularly limited, but for example, a hot air heater and an infrared heater can be used. Heating and drying can be performed before printing, during printing, after printing, and the like.
Further, the recording device and the recording method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, those that form patterns such as geometric patterns and those that form a three-dimensional image are also included.
Further, the recording device includes both a serial type device that moves the discharge head and a line type device that does not move the discharge head, unless otherwise specified.
Further, as this recording device, it is possible to use not only a desktop type but also a wide recording device capable of printing on an A0 size recording medium, or, for example, continuous paper wound in a roll shape as a recording medium. A continuous line printer is also included.
An example of the recording device will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective explanatory view of the device. FIG. 2 is a perspective explanatory view of the main tank. The image forming apparatus 400 as an example of the recording apparatus is a serial type image forming apparatus. A mechanical unit 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink storage section 411 of the main tank 410 (410k, 410c, 410m, 410y) for each color of black (K), cyan (C), magenta (M), and yellow (Y) is, for example, a package of an aluminum laminated film or the like. It is formed of members. The ink container 411 is housed in, for example, a plastic container case 414. As a result, the main tank 410 is used as an ink cartridge for each color.
On the other hand, a cartridge holder 404 is provided behind the opening when the cover 401c of the apparatus main body is opened. A main tank 410 is detachably attached to the cartridge holder 404. As a result, each ink ejection port 413 of the main tank 410 and the ejection head 434 for each color communicate with each other via the supply tube 436 for each color, and ink can be ejected from the ejection head 434 to the recording medium.

This recording device can include not only a portion that ejects ink, but also a device called a pretreatment device, a posttreatment device, and the like.
As one aspect of the pretreatment apparatus and the posttreatment apparatus, it has a pretreatment liquid and a posttreatment liquid as in the case of inks such as black (K), cyan (C), magenta (M), and yellow (Y). There is an embodiment in which a liquid accommodating portion and a liquid discharge head are added, and a pretreatment liquid or a posttreatment liquid is discharged by an inkjet recording method.
As another aspect of the pretreatment device and the posttreatment device, there is a mode in which a pretreatment device and a posttreatment device by, for example, a blade coating method, a roll coating method, and a spray coating method are provided other than the inkjet recording method.

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

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

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

In addition, image formation, recording, printing, printing, etc. in the terms of the present invention are all synonymous terms.
Recording media, media, and printed matter are all synonymous.
Liquid discharge device and image forming device are synonymous.

In the liquid ejection device of the present invention, a chromatic ink ejection nozzle array (color nozzle array) in which nozzles for ejecting chromatic ink are arranged and an achromatic ink ejection nozzle array in which nozzles for ejecting achromatic ink containing resin are arranged. It has a (clear nozzle row) and a metallic ink ejection nozzle row (metal nozzle row) in which nozzles for ejecting metallic ink containing an organic solvent are arranged, and after ejecting the chromatic ink on a recording medium, the metallic ink The achromatic ink is ejected to the region where the achromatic ink is ejected, and the metallic ink is ejected to the region where the achromatic ink is ejected. It is preferably configured to form a layer.
Further, the ink set of the present invention includes chromatic ink, achromatic ink and metallic ink, the achromatic ink contains a resin, the metallic ink contains an organic solvent, and is used in the liquid ejection device of the present invention. It is a thing.
Further, the image forming method of the present invention includes a chromatic ink ejection step in which the achromatic ink contains a resin, the metallic ink contains an organic solvent, and the chromatic ink is ejected onto a recording medium, and the chromatic ink ejection. After the step, the area for ejecting the metallic ink includes an achromatic ink ejection step for ejecting the achromatic ink, and a metallic ejection step for ejecting the metallic ink to the area for ejecting the achromatic ink.

FIG. 11 is a block diagram of an example of the liquid discharge device of the present invention. The liquid discharge device 10 has an image processing unit 12 and an image forming unit 30.
The image processing unit 12 includes a main control unit 13 and a recording control unit 28. The main control unit 13 is a computer configured to include a CPU (Central Processing Unit) and the like, and controls the entire image processing unit 12. The main control unit 13 may be configured by a CPU other than a general-purpose CPU. For example, the main control unit 13 may be configured by a circuit or the like. The recording control unit 28 is also a computer configured to include a CPU (Central Processing Unit) and the like like the main control unit 13, and even if it is the same computer as the main control unit 13, it is separately provided. You may.
The main control unit 13 includes a data receiving unit 12A, a data creating unit 12B, a data output unit 12C, and a data determining unit 12D. A part or all of the data receiving unit 12A, the data creating unit 12B, the data output unit 12C, the data determining unit 12D, and the recording control unit 28 are realized by, for example, causing a processing device such as a CPU to execute a program, that is, by software. It may be realized by hardware such as IC (Integrated Circuit), or it may be realized by using software and hardware in combination.
The data receiving unit 12A receives the image data. The image data is information such as the shape and color of the image to be formed. The data receiving unit 12A may acquire image data from an external device via a communication unit, or may acquire image data from a storage means provided in the image processing unit 12. The received data is output to the data determination unit 12D and the data creation unit 12B.
The data determination unit 12D determines whether or not metallic ink is used based on the color information in the image data received by the data receiving unit 12A. The determination result is output to the data creation unit 12B.
The data creation unit 12B performs predetermined data processing such as mask processing based on the received image data and the determination result, and creates discharge data. The ejection data includes chromatic ink ejection data for creating a chromatic image formed by chromatic ink, clear ink ejection data for creating a clear image formed by clear ink, and metallic ink. Metallic ink ejection data for creating a metallic image can be mentioned. When achromatic color is not included as the color information of the image data, clear ink ejection data for creating a clear ink image is created based on the metallic color information so as to include an area forming the metallic image. To do. The created discharge data is output to the data output unit 12C.
The data output unit 12C outputs the discharge data created by the data creation unit 12B to the recording control unit 28.
The recording control unit 28 controls the recording unit 14 and the driving unit 25 of the image forming unit 30 so as to eject droplets corresponding to each pixel from the ejection head based on the ejection data received from the data output unit 12C. ..
The recording unit 14 is an inkjet type carriage provided with a plurality of ejection heads provided with a plurality of nozzles, and records dots by ejecting droplets from the nozzles of the heads.
The drive unit 25 includes a first drive unit 23 and a second drive unit 24, and the first drive unit 23 moves the recording unit 14 in the vertical direction Z, the main scanning direction X, and the sub-scanning direction Y. The second drive unit 24 moves the recording medium in the vertical direction Z, the main scanning direction X, and the sub scanning direction Y.
In the present invention, the achromatic ink is controlled to be ejected to the region forming the metallic ink layer. For example, the achromatic ink is controlled to be ejected so as to cover the entire region forming the metallic ink layer.

FIG. 12 is a flowchart of image formation in the present invention.
First, the data receiving unit 12A acquires the image data (S100) and outputs it to the data creating unit 12B and the data determination unit 12D. Next, the process proceeds to step S101.

Based on the received image data, the data determination unit 12D confirms whether or not the metallic ink is used (S101). If it is used, the process proceeds to step S102. If not used, the process proceeds to step S106.

Based on the received image data and the determination result, the data creation unit 12B creates chromatic ink ejection data (S102), and proceeds to step S103.

The data creation unit 12B creates achromatic (clear) ink ejection data (S103), and proceeds to step S104.

The data creation unit 12B creates metallic ink ejection data (S104), and outputs the created ejection data to the data output unit 12C. The data output unit 12C outputs discharge data to the recording control unit 28. The process proceeds to step S105.

The recording control unit 28 forms an image based on the received discharge data (S105).

On the other hand, based on the received image data, the data determination unit 12D confirms whether or not the metallic ink is used (S101), and if it is not used, the process proceeds to step S106, and in step S106, ejection data is created and an image is formed. Will be done.

FIG. 13 is a schematic cross-sectional view of an image formed by the liquid discharge device of the present invention.
In FIG. 13A, a chromatic ink layer is provided on the recording medium, an achromatic ink layer is provided so as to cover the entire chromatic ink layer, and a metallic ink layer is provided above the achromatic ink layer. Has been done.
In FIG. 13B, a solid image of the achromatic ink layer and the metallic ink layer is provided on the chromatic ink layer on the recording medium.
FIG. 13C has almost the same form as that of FIG. 13B, but the metallic ink layer is laminated on a part of the achromatic ink layer.
In FIG. 13D, metallic ink layers are laminated at a plurality of locations on the achromatic ink layer.
In FIG. 13E, achromatic ink layers are provided at a plurality of locations on the chromatic ink layer, and metallic ink layers are laminated on the individual achromatic ink layers.
In FIG. 13 (f), a plurality of chromatic ink layers are provided on the recording medium, an achromatic ink layer is provided so that all of the chromatic ink layers are covered, and metallic ink is provided on the upper portion of the achromatic ink layer. Layers are provided.
The present invention is not limited to the form shown in FIG.
Further, as shown in FIG. 13, the achromatic ink layer is formed in the area where the metallic ink layer is created, and if the entire lower portion of the metallic ink layer can be supported, the achromatic ink layer is provided over the entire recording medium. You don't have to make money.

FIG. 3A is a plan view for explaining the liquid ejection device of the present invention, and FIG. 3B is a diagram for showing a form in which an ink set is loaded in the ejection head.
As shown in FIG. 3A, the carriage 133 is slidably held in the main scanning direction by the guide rod 131 and the stay (not shown), which are guide members laid horizontally on the left and right side plates (not shown). , The main scanning motor (not shown) moves and scans in the direction indicated by the arrow in FIG. 3 (a).
The carriage 133 is provided with a color nozzle row 31 for ejecting ink droplets of chromatic inks, for example, yellow (Y), cyan (C), magenta (M), and black (Bk), and ink droplets of achromatic ink. A recording head 134 having a clear nozzle row 32 for ejecting and a metal nozzle row 33 for ejecting ink droplets of metallic ink is attached, and each nozzle row faces the recording medium 142.

The inkjet recording head constituting the recording head 134 includes a piezoelectric actuator such as a piezoelectric element, a thermal actuator that utilizes a phase change due to boiling of a liquid film using an electrothermal conversion element such as a heat generating resistor, and a metal phase due to a temperature change. A shape memory alloy actuator that uses change, an electrostatic actuator that uses electrostatic force, or the like provided as an energy generating means for ejecting ink can be used.

Further, as shown in FIG. 3B, in each nozzle row in the recording head 134, the clear nozzle row 32 is arranged upstream of the color nozzle row 31 and metal is arranged upstream of the clear nozzle row 32 in the scanning direction of the carriage 131. The nozzle row 33 is arranged. In a preferred embodiment, the nozzle rows are arranged in the order of the metal nozzle row, the clear nozzle row, the color nozzle row, the clear nozzle row, and the metal nozzle row from the downstream to the upstream with respect to the scanning direction of the carriage. (FIG. 4A), such an arrangement increases the printing speed when the colors are superimposed in the order of the color ink, the clear ink, and the metallic ink, and the productivity is improved. Further, as shown in FIG. 4B, the recording head 134 can be printed in the reciprocating direction, and the printing speed can be increased by such an arrangement.
In addition, in the form of FIGS. 3 and 4, it is an example in which each nozzle row is arranged side by side in one recording head, but the present invention is not limited to this, and as described below, each nozzle row is plural. It may be arranged side by side on the head of.

In the embodiment of FIG. 5, the color nozzle row 31, the clear nozzle row 32, and the metal nozzle row 31 are arranged side by side on a plurality of heads, and in the recording head 134 at the lower side of FIG. 5, the color nozzle row 31 is arranged in the scanning direction of the carriage 133. The clear nozzle row 32 is arranged upstream of the clear nozzle row 32, and the metal nozzle row 33 is arranged upstream of the clear nozzle row 32.

In the embodiment of FIG. 6, the recording head having the color nozzle row 31 and the recording head having the clear nozzle row 32 and the metal nozzle row 31 are arranged side by side, and in the recording head 134 above FIG. 6, in the scanning direction of the carriage 133. , The metal nozzle row 33 is arranged downstream of the clear nozzle row 32.

In the embodiment of FIG. 7, the liquid discharge device of the present invention includes a transport means for transporting a recording medium, and has a recording head having a plurality of color nozzle rows 31, a recording head having a clear nozzle row 32, and a metal nozzle row 33. A plurality (three) of the recording heads to be held are arranged side by side, the clear nozzle row 32 is arranged downstream of the color nozzle row 31 and the metal nozzle row 33 is arranged downstream of the clear nozzle row 32 in the transport direction of the recording medium. Is placed.

In the embodiment of FIG. 8, the liquid discharge device of the present invention includes a transport means for transporting a recording medium, and a recording head having a plurality of color nozzle rows 31 and a recording head having a clear nozzle row 32 and a metal nozzle row 33 are provided. , A plurality (two) are arranged, and the clear nozzle row 32 and the metal nozzle row 33 are arranged downstream of the color nozzle row 31 in the transport direction of the recording medium, and at least one clear nozzle is arranged in the scanning direction of the carriage 133. A metal nozzle row 33 is arranged upstream of the row 32.

In the embodiment of FIG. 9, the liquid discharge device of the present invention includes a transport means for transporting a recording medium, and a recording head having a plurality of color nozzle rows 31 and a recording head having a clear nozzle row 32 and a metal nozzle row 33 are provided. , A plurality (two) are arranged, and the clear nozzle row 32 and the metal nozzle row 33 are arranged downstream of the color nozzle row 31 in the transport direction of the recording medium, and the color nozzle row 31, the clear nozzle row 32 and the metal nozzle row are arranged. One of the recording heads provided with the 33 is provided with a color nozzle row 31, a clear nozzle row 32, and a metal nozzle row 33 in this order from upstream to downstream in the transport direction of the recording medium.

In the embodiment of FIG. 10, the liquid discharge device of the present invention includes a transport means for transporting the recording medium, and the recording head 134 has a color nozzle row 31 and a clear nozzle row 32 from upstream to downstream in the transport direction of the recording medium. And the metal nozzle row 33 are provided in this order.

In this way, color ink, clear ink, and metallic ink are formed on each image on the recording medium.
The amount of ink adhered to the recording medium is not particularly limited, but the color ink is ^{preferably 5 to 20 g / m 2} per color, more preferably 8 to 15 g / m ² , and the clear ink is preferably 5 to ^{20 g / m 2.} , more preferably 8~15g / ^{m 2,} the metallic ink is preferably 5 to 15 g / ^{m 2,} more preferably 8-12 g / ^{m 2.}

The method for analyzing various components used in the present invention will be described below.

<Resin quantification method>
Examples of the resin quantification method include a method of observing mass attenuation with heating using TG-DTA. The resin can be quantified by first evaporating all the water and solvent components, measuring the weight loss, and then measuring the mass loss due to heating of the solid content again. In addition, there is also a method of separating the resin component and measuring the mass.

<Qualitative and quantitative method of organic solvent>
There are several methods for qualitative and quantification of organic solvents. For example, a method using GC-MS can be mentioned. In addition, it is possible to quantify the absolute quantity by creating a calibration curve.

<Qualitative method of coloring material>
There are several qualitative methods for the color material in the ink, and for example, the qualitative method using SEM-EDX can be mentioned.

Hereinafter, the present invention will be further described with reference to Examples and Comparative Examples, but the present invention is not limited to these examples. In addition, "part" shows mass part, and the amount (%) of a component shows mass%.

Preparation of water dispersion of silver particles 68.1 parts of silver nitrate, polymer dispersant having a carboxyl group (manufactured by Big Chemie, "Disperbic 190", solvent: water, non-volatile component 40%, acid value 10 mgKOH / g, amine value 0) 7.2 parts and 1.7 parts of cole acid (manufactured by Wako Pure Chemical Industries, Ltd.) were added to 100 parts of ion-exchanged water and stirred vigorously to obtain a suspension. To this suspension, 100 parts of dimethylaminoethanol (manufactured by Wako Pure Chemical Industries, Ltd.) was gradually added so that the water temperature did not exceed 50 ° C., and then heated and stirred in a water bath at a water temperature of 50 ° C. for 3 hours. The obtained reaction solution was filtered through a glass filter (GC-90 manufactured by ADVANTEC, pore size 0.8 μm), and silver was 14.5%, polymer dispersant was 0.6%, and dimethylaminoethanol was 47. A silver particle dispersion containing 3% was obtained.

Preparation of scaly aluminum diethylene glycol diethyl ether dispersion In a stainless steel container, 94 parts of diethylene glycol diethyl ether (manufactured by Nippon Emulsifier) and 3.1 parts of cellulose acetate butyrate (butylation rate 35-39%, manufactured by Kanto Chemical Co., Inc.) are placed. It was charged and mixed sufficiently with a high-speed disperser. This was uniformly bar-coated on a PET film and dried at 70 ° C. for 10 minutes. Next, using a vacuum vapor deposition apparatus (VE-1010 type vacuum vapor deposition apparatus manufactured by Vacuum Device Co., Ltd.), aluminum vapor deposition is performed after setting the number of parts to 16 for 1 part of the above cellulose acetate butyrate resin. It was. This laminate was stripped, refined and dispersed in diethylene glycol diethyl ether for 14 hours using a VS-150 ultrasonic disperser (manufactured by AS ONE Corporation). The concentration of the obtained solution was adjusted using diethylene glycol diethyl ether, and a scaly aluminum diethylene glycol diethyl ether dispersion containing 20% aluminum, 1.4% cellulose acetate butyrate resin, and 77.2% diethylene glycol diethyl ether was prepared. Obtained.

Preparation of scaly aluminum 2-aminoethanol dispersion In a stainless steel container, 94 parts of diethylene glycol diethyl ether (manufactured by Nippon Emulsifier) and 3.1 parts of cellulose acetate butyrate (butylation rate 35-39%, manufactured by Kanto Chemical Co., Inc.) Was added and mixed sufficiently with a high-speed disper. This was uniformly bar-coated on a PET film and dried at 70 ° C. for 10 minutes. Next, using a vacuum vapor deposition apparatus (VE-1010 type vacuum vapor deposition apparatus manufactured by Vacuum Device Co., Ltd.), aluminum vapor deposition is performed after setting the number of parts to 16 for 1 part of the above cellulose acetate butyrate resin. It was. This laminate was peeled, refined and dispersed in 2-aminoethanol (manufactured by Tokyo Chemical Industry Co., Ltd.) for 14 hours using a VS-150 ultrasonic disperser (manufactured by AS ONE Corporation). The concentration of the obtained solution was adjusted using 2-aminoethanol, and scaly aluminum 2-aminoethanol containing 20% aluminum, 1.4% cellulose acetate butyrate resin, and 76.9% 2-aminoethanol was added. A dispersion was obtained.

Preparation of Polycarbonate Urethane Resin Water Dispersion 1450 parts of polycarbonate diol (reaction product of 1,6-hexanediol and dimethyl carbonate), 2,2-dimethylol in a reaction vessel containing a stirrer, a reflux condenser and a thermometer. 230 parts of propionic acid (DMPA) and 1370 parts of 2-aminoethanol were charged under a nitrogen stream and heated to 60 ° C. to dissolve DMPA.
Next, 1420 parts of 4,4'-dicyclohexylmethane diisocyanate and 2.7 parts of dibutyltin dilaurylate (catalyst) were added and heated to 90 ° C., and a urethanization reaction was carried out over 5 hours to obtain an isocyanate-terminated urethane prepolymer. It was.
The reaction mixture was cooled to 80 ° C., 142 parts of triethylamine was added and mixed, and 4100 parts were extracted and added to a mixed solution of 5200 parts of water and 15 parts of triethylamine under strong stirring.
Next, 1500 parts of ice was added, 626 parts of a 35 mass% 2-methyl-1,5-pentanediamine aqueous solution was added to carry out a chain extension reaction, and the solvent was distilled off so that the solid content concentration became 30%. , Polycarbonate-based urethane resin aqueous dispersion (urethane resin component 30%, 2-anoethanol 6%) was obtained.

Preparation of Diethylene Glycol Diethyl Ether Disperse Methacrylate Resin 100 parts of methyl methacrylate, 50 parts of n-butyl methacrylate, 50 parts of ε-caprolactone and t-butylperoxy-2-in 300 parts of diethylene glycol diethyl ether kept at 100 ° C. The mixture with 6.3 parts of ethyl hexanoate was added dropwise over 1.5 hours. After completion of the dropping, the mixture was reacted at 100 ° C. for 2 hours and then cooled to adjust the solid content concentration to 30% and diethylene glycol diethyl ether to 70% using diethylene glycol diethyl ether, and the methacrylic acid resin diethylene glycol diethyl ether dispersion was prepared. Obtained.

Preparation of methacrylic acid resin 2-aminoethanol dispersion In 300 parts of 2-aminoethanol kept at 100 ° C., 100 parts of methyl methacrylate, 50 parts of n-butyl methacrylate, 50 parts of ε-caprolactone and t-butylperoxy- The mixture with 6.3 parts of 2-ethylhexanoate was added dropwise over 1.5 hours. After completion of the dropping, the mixture was reacted at 100 ° C. for 2 hours and then cooled, and the solid content concentration was adjusted to 30% and 2-aminoethanol 70% using 2-aminoethanol, and the methacrylic acid resin 2-aminoethanol was used. A dispersion was obtained.

Preparation of chromatic pigment-dispersed polymer solution After sufficient nitrogen gas substitution in a 1 L flask equipped with a mechanical stirrer, thermometer, nitrogen gas introduction tube, reflux tube, and dropping funnel, 11.2 g of styrene and 2 acrylic acid 0.8 g, 12.0 g of lauryl methacrylate, 4.0 g of polyethylene glycol methacrylate, 4.0 g of styrene macromer, and 0.4 g of mercaptoethanol were mixed and heated to 65 ° C.
Next, styrene 100.8 g, acrylic acid 25.2 g, lauryl methacrylate 108.0 g, polyethylene glycol methacrylate 36.0 g, hydroxyl ethyl methacrylate 60.0 g, styrene macromer 36.0 g, mercaptoethanol 3.6 g, azobismethylvalero. A mixed solution of 2.4 g of nitrile and 18.0 g of methyl ethyl ketone was added dropwise into the flask over 2.5 hours. After the dropping, a mixed solution of 0.8 g of azobismethylvaleronitrile and 18 g of methyl ethyl ketone was dropped into the flask over 0.5 hours. After aging at 65 ° C. for 1 hour, 0.8 g of azobismethylvaleronitrile was added and the mixture was further aged for 1 hour. After completion of the reaction, 364.0 g of methyl ethyl ketone was added into the flask to obtain 800 g of a polymer solution having a concentration of 50% by mass.

Preparation of black pigment dispersion 28 g of polymer solution, 42 g of carbon black (NIPEX150, manufactured by Degusa), 13.6 g of 1 mol / L potassium hydroxide aqueous solution, 20.0 g of methyl ethyl ketone, and 13.6 g of ion-exchanged water are sufficient. After stirring, the mixture was kneaded using a roll mill.
The obtained paste was put into 200 g of pure water, stirred sufficiently, methyl ethyl ketone and water were distilled off using an evaporator, and a polyvinylidene fluoride membrane filter having an average pore size of 5.0 μm was used to remove coarse particles. The mixture was filtered under pressure to obtain a black pigment dispersion containing 15% by mass of a pigment, 5% by mass of a resin component, and 20% by mass of a solid content.

Preparation of Metallic Ink, Black Ink and Clear Ink The respective formulations (parts by mass) shown in Table 1 were mixed and stirred to obtain metallic ink, black ink and clear ink, respectively.

<Printer preparation>
The exterior of the inkjet printer (IPSiO GXe5500 manufactured by Ricoh Co., Ltd.) was removed, a rear multi-manual feed feeder was attached, and the evaluation ink was passed through the ink supply path including the recording head for cleaning. After repeating the work 6 times in total, a printing device for evaluation was used in a state where all the ink used for cleaning was completely removed.
The gas in the evaluation ink was degassed by stirring the evaluation ink under a reduced pressure condition of 5 Pa to 10 Pa for 30 minutes, and the ink was placed in a cartridge after being filled in the ink storage bag, and it was confirmed that the evaluation ink was filled. Next, after selecting the glossy paper clean mode with the driver attached to the printer, the color matching off was set to the print mode in the user settings. In this print mode, the ejection amount was adjusted by changing the drive voltage of the head so that the amount of each ink adhering to the recording medium of the solid image was 20 g / m ^2.

<Creation of evaluation image>
After making the above preparations, a glossy polyvinyl chloride sheet (Roland DG, model number SV-G-1270G) is used with Microsoft Word2003 (manufactured by Microsoft) as a recording medium, and a solid image of 150 mm × 150 mm is formed on the sheet. Ten sheets were printed at 25 ° C. and used for evaluation. The evaluation results are shown in Table 3.
In the solid image of the embodiment, the achromatic ink is ejected to the region where the metallic ink is ejected after the chromatic ink ejection step of ejecting the chromatic ink onto the recording medium and the chromatic ink ejection step. It is formed through a process of ejecting achromatic ink and a metallic ejection step of ejecting the metallic ink into a region where the achromatic ink is ejected. The solid images of the comparative examples were created in the printing order shown in Table 2 as in the examples.

<Evaluation of metallic luster>
The 20 ° glossiness of the solid image was measured with a glossiness meter (Microtrigloss manufactured by BYK Gardener) and evaluated according to the following criteria. C or higher is a practical level. The metallic luster was measured from the printing surface side of the image on the recording medium.
[Evaluation criteria]
A: 20 ° glossiness is 400 or more and B: 20 ° glossiness is 300 or more and less than 400 C: 20 ° glossiness is 200 or more and less than 300 D: 20 ° glossiness is 100 or more and less than 200 E: 20 ° glossiness Degree less than 100

<Evaluation of abrasion resistance>
Set the dried printed matter on the Gakushin type wear fastness tester AB-301 (manufactured by Tester Sangyo Co., Ltd.), and use a friction element (load; 300 g) with a white cotton cloth (JIS L 0803 compliant) attached to the contact part. It was rubbed 10 times, and the degree of deterioration was visually observed and evaluated according to the following criteria. C or higher is a practical level. For the evaluation, the metallic image portion on the printing surface side of the image formed on the recording medium was measured.
[Evaluation criteria]
A: The number of scratches is less than 3, and the base is not visible.
B: The number of scratches is 3 or more and less than 7, and the base is not visible.
C: The number of scratches is 7 or more and less than 10, and the base is not visible.
D: The number of scratches is 10 or more, and the base is exposed.

The results are shown in Table 3.

In Table 2, the clear metal both ends arrangement is a liquid discharge device in which a head 134 having eight rows of nozzle rows is mounted on a carriage in the form shown in FIGS. 4 (a) and 4 (b), and is one end side in the carriage scanning direction. Therefore, one row of metallic ink, one row of clear ink, four rows of color ink, one row of clear ink, and one row of metallic ink are arranged, and reciprocating printing is possible.
Further, the clear metal one-sided arrangement is a liquid ejection device in which a head 2 having 6 rows of nozzle rows is mounted on a carriage in FIG. 3 (b), and 1 row of metallic ink and 1 row of clear ink from the upstream side in the carriage scanning direction. , 4 rows of color inks are arranged, and printing is performed in one side.

From the results in Table 3, it was found that in each example, excellent metallic luster and abrasion resistance can be achieved at the same time when decorative printing using metallic ink is performed.

10 Liquid discharge device 12 Image processing unit 12A Data receiving unit 12B Data creation unit 12C Data output unit 12D Data judgment unit 13 Main control unit 14 Recording unit 23 1st drive unit 24 2nd drive unit 25 Drive unit 28 Recording control unit 30 Image Forming part 31 Color nozzle row 32 Clear nozzle row 33 Metal nozzle row 131 Guide rod 133 Carriage 134 Recording head 142 Recording medium 400 Image forming device 401 Image forming device exterior 401c Device body cover 404 Cartridge holder 410 Main tank 410k, 410c, Main tank for each color of 410m, 410y black (K), cyan (C), magenta (M), yellow (Y) 411 Ink storage unit 413 Ink discharge port 414 Storage container case 420 Mechanical unit 434 Discharge head 436 Supply tube

Japanese Unexamined Patent Publication No. 2016-815 Japanese Unexamined Patent Publication No. 2007-276482

Claims (13)

A row of chromatic ink ejection nozzles in which nozzles for ejecting chromatic ink are arranged, and
A row of achromatic ink ejection nozzles in which nozzles for ejecting achromatic ink containing resin are arranged,
A row of metallic ink ejection nozzles in which nozzles for ejecting metallic ink containing an organic solvent are arranged is arranged side by side on one or a plurality of heads.
After ejecting the chromatic ink onto the recording medium,
The achromatic ink is discharged into the area where the metallic ink is discharged, and the achromatic ink is discharged.
A liquid ejection device characterized in that the metallic ink is ejected to a region where the achromatic ink is ejected. The liquid according to claim 1, wherein an achromatic ink layer formed of the achromatic ink is formed between the chromatic ink layer formed of the chromatic ink and the metallic ink layer formed of the metallic ink. Discharge device. The liquid ejection device according to claim 1 or 2, wherein the organic solvent contained in the metallic ink is an ether solvent. The liquid ejection device according to any one of claims 1 to 3, wherein the metallic ink contains aluminum. The liquid ejection device according to any one of claims 1 to 4, wherein the resin in the achromatic ink is 1% by mass or more and 30% by mass or less. The liquid ejection device according to any one of claims 1 to 5, wherein the metallic ink contains a resin, and the resin in the metallic ink is 5% by mass or less. The liquid ejection device according to any one of claims 1 to 6, further comprising a chromatic ink, an achromatic ink, and a metallic ink. A row of color nozzles that eject chromatic ink and
A row of clear nozzles that eject achromatic ink containing resin,
A row of metal nozzles for ejecting metallic ink containing an organic solvent is arranged side by side on one or more heads.
In the scanning direction of the carriage that scans the one or more heads.
The clear nozzle row is arranged upstream of the color nozzle row, and the clear nozzle row is arranged.
The metal nozzle row is arranged upstream of the clear nozzle row.
A liquid discharge device characterized by the fact that. A transport means for transporting a recording medium and
A row of color nozzles that eject chromatic ink and
A row of clear nozzles that eject achromatic ink containing resin,
A row of metal nozzles for ejecting metallic ink containing an organic solvent is arranged side by side on one or more heads.
In the transport direction of the recording medium
The clear nozzle row is arranged downstream of the color nozzle row, and the clear nozzle row is arranged.
The metal nozzle row is arranged downstream of the clear nozzle row, and the metal nozzle row is arranged.
A liquid discharge device characterized by the fact that. A transport means for transporting a recording medium and
A row of color nozzles that eject chromatic ink and
A row of clear nozzles that eject achromatic ink containing resin,
A row of metal nozzles that eject metallic ink containing an organic solvent are arranged side by side on a plurality of heads.
In the transport direction of the recording medium, the clear nozzle row and the metal nozzle row are arranged downstream of the color nozzle row.
The metal nozzle row is arranged upstream of the clear nozzle row in the scanning direction of the carriage that scans the plurality of heads.
A liquid discharge device characterized by the fact that. After ejecting the chromatic ink onto the recording medium,
The achromatic ink is discharged into the area where the metallic ink is discharged, and the achromatic ink is discharged.
The liquid ejection device according to any one of claims 8 to 10, wherein the metallic ink is ejected to a region where the achromatic ink is ejected. An ink set used in the liquid ejection device according to any one of claims 1 to 11.
Equipped with chromatic ink, achromatic ink and metallic ink,
An ink set in which the achromatic ink contains a resin and the metallic ink contains an organic solvent. An image forming method that uses chromatic ink, achromatic ink, and metallic ink.
The achromatic ink contains a resin, and the metallic ink contains an organic solvent.
A chromatic ink ejection process for ejecting the chromatic ink onto a recording medium,
After the chromatic ink ejection step, the achromatic ink ejection step of ejecting the achromatic ink to the area where the metallic ink is ejected, and the achromatic ink ejection step.
A metallic ejection step of ejecting the metallic ink to the region where the achromatic ink is ejected, and a metallic ejection process.
An image forming method characterized by having.

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