JP2019025905A - Image formation method, recorded matter, and image formation device - Google Patents

Abstract

To provide an image formation method that makes it possible to obtain recorded matter having the capability of supporting a wide range of media and having excellent metallic luster and image clarity.SOLUTION: An image formation method has a porous structure forming step for applying a porous structure forming material onto a recording medium with an inkjet head, to a porous structure with an average pore diameter of more than 200 nm and 400 nm or less and an average thickness of 5 μm or more and 30 μm or less, and a silver ink application step for applying silver ink containing silver onto the porous structure.SELECTED DRAWING: None

Description

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

  In recent years, diversification of print media has progressed. The print medium is used in a wide range of fields, for example, from office printing to large-scale printing such as commercial printing.

  The printed matter printed on the printing medium can express a full color image in which each color is mixed.

  A printed matter having an image containing a metallic luster, particularly a silver color material having a high specular imaging property, can obtain a full-color and high image clarity image by mixing the silver coloring material with other colors. The industrial utility value is very high.

  Thus, for example, a printing method has been proposed in which a printed matter having high gloss can be obtained by printing an ink composition containing a metal colloid on the surface of a porous material to be printed (see, for example, Patent Document 1).

  Further, there has been proposed a recorded matter on which an image having excellent light resistance and brightness is recorded by forming a resin layer on the surface of the silver pigment layer (see, for example, Patent Document 2).

  Furthermore, an ink jet recording method has been proposed in which recording is performed on a recording medium having pores having an average pore diameter of 3 nm or more and 200 nm or less using an ink composition containing a bright pigment having an average particle diameter of 1 nm or more and 100 nm or less. (For example, refer to Patent Document 3).

  SUMMARY OF THE INVENTION An object of the present invention is to provide an image forming method capable of obtaining a recorded material having wide media compatibility and excellent in metallic luster and image clarity.

  In the image forming method of the present invention as a means for solving the above-described problem, a porous forming material is provided on a recording medium using an inkjet head, the average pore diameter is more than 200 nm and not more than 400 nm, and the average A porous forming step of forming a porous layer having a thickness of 5 μm to 30 μm, and a silver ink applying step of applying a silver ink containing silver on the porous layer.

  According to the present invention, it is possible to provide an image forming method capable of obtaining a recorded material having a wide media compatibility and excellent in metallic luster and image clarity.

FIG. 1 is a diagram illustrating an example of an image forming apparatus that performs the image forming method of the present invention. FIG. 2 is a perspective explanatory view showing an example of a main tank of the image forming apparatus of FIG. FIG. 3 is a scanning electron microscope (sometimes referred to as SEM) image showing an example of the surface of the recording medium when silver ink is applied to the recording medium using an inkjet head. FIG. 4 is a schematic diagram illustrating an example of a method for calculating the average pore diameter of the porous material. FIG. 5 is a schematic view showing an example of a method for calculating the average thickness of the porous material.

(Image forming method and image forming apparatus)
The image forming method of the present invention includes a porous forming step and a silver ink applying step, and preferably includes at least one of a color ink applying step and a laminate layer forming step, and further includes other steps as necessary. Including.
The image forming apparatus of the present invention preferably includes a porous forming unit and a silver ink applying unit, and preferably includes at least one of a color ink applying unit and a laminate layer forming unit, and other units as necessary. Have

In the conventional image forming method, the silver particles easily settle, and the silver ink may contain a dispersant in order to improve the dispersion stability of the silver ink. However, when silver ink is applied on a recording medium without an ink receiving layer, there is a problem that a metallic luster cannot be obtained because a large amount of the dispersant remains.
Further, when a porous layer is formed as the ink receiving layer on the recording medium, there is a problem that image clarity cannot be obtained if the average pore diameter and the average thickness of the porous layer are not appropriate.
Furthermore, when a so-called non-permeable substrate without an ink receiving layer is used as a recording medium, high image clarity cannot be obtained, and in particular, metallic gloss and image clarity cannot be maintained for a long time.
On the other hand, according to the present invention, the recording medium has wide media compatibility including a recording medium without an ink receiving layer and a recording medium without an appropriate ink receiving layer, and has excellent metallic gloss and image clarity. An image forming method for obtaining a product can be provided.

<Porous forming step and porous forming means>
In the porous forming step, a porous forming material is provided on a recording medium using a porous forming means, the average pore diameter is more than 200 nm and not more than 400 nm, and the average thickness is not less than 5 μm and not more than 30 μm. It is a process of forming a quality and is preferably performed by an ink jet head.
In the porous forming step, a bar coater or the like can be used in addition to the ink jet head.
Examples of the porous forming means include means for applying the porous forming material to the recording medium using an ink jet head, but a bar coater or the like can also be used.
Furthermore, it is preferable to have a step of drying the solvent contained in the porous forming material after applying the porous forming material to the recording medium, and the drying step includes hot air drying, Natural drying is used.
When an ink jet head is used as the porous forming means, an ink jet head different from the ink jet head as the silver ink applying means may be used, or different nozzle rows of the same ink jet head may be used.

<Porous forming step and porous forming means>
In the porous forming step, a porous forming material is provided on a recording medium using an ink jet head, and an average pore diameter is more than 200 nm and not more than 400 nm, and an average thickness is not less than 5 μm and not more than 30 μm. This is a step of forming and is performed by a porous forming means.
As the porous forming step, a bar coater or the like can be used in addition to the ink jet head.
Examples of the porous forming means include means for applying the porous forming material to the recording medium using an ink jet head, but a bar coater or the like can also be used.
Furthermore, it is preferable to include a step of drying the solvent contained in the porous forming material after applying the porous forming material to the recording medium. As the drying step, for example, hot air drying, natural drying, or the like is used.

<< Porous >>
The porous is formed on a recording medium using a porous forming material, the average pore diameter of the porous is more than 200 nm and not more than 400 nm, and the average thickness of the porous is not less than 5 μm and not more than 30 μm.
The porous material may have pores that absorb the solution and resin contained in the ink without absorbing silver in the ink.
In the present invention, the term “pore” refers to a void observed when the porous formed on the recording medium is observed from the porous forming surface side. In addition, as an observation method, observing the image which image | photographed the said porous on the said recording medium using SEM is mentioned.
In the present invention, the hole diameter refers to the lengths of the two longest and shortest diagonal lines (for example, a (FIG. 4, 101) and b (FIGS. 4, 102) for the observed hole (FIGS. 4, 100). )), The average value of the two diagonal lines ((a + b) / 2). Note that the length of the diagonal line is obtained from the porous SEM image.
In the present invention, the porous average pore diameter means an average value of the porous pore diameters. When determining the average value, the porous pore diameter of 100 nm or less is not considered in the calculation. Specifically, in the SEM image on the surface of the recorded material, the voids observed in the 10 μm square porous region where silver ink and color ink are not attached are calculated, and an average value is taken.
In the present invention, the average thickness of the porous material is calculated from an SEM image on a cut surface of a dried recorded material in the vertical direction. Specifically, as shown in FIG. 5, the midpoint M1 of the cross section of the region where the porous 10 is formed on the recording medium 11, the midpoint M2 between the end E1 of the cross section and the midpoint M1, and the cross section It means the average value of the porous thickness at a total of three points, that is, the other end E2 of the intermediate point M3 and the intermediate point M3 of the midpoint M1.
In addition, about the part whose average pore diameter of the said porous exceeds 200 nm and is not less than 400 nm, it does not use for calculation of the average thickness of a porous. Further, the coating layer previously formed on the recording medium is not used in the calculation of the average porous thickness in the present invention.

The porous average pore diameter is more than 200 nm and 400 nm or less, preferably 201 nm or more and 400 nm or less, more preferably 220 nm or more and 360 nm or less, and further preferably 250 nm or more and 360 nm or less.
When the average pore diameter is 200 nm or less, the absorption of vehicles such as solvents and dispersants is not sufficient, and image clarity cannot be obtained. On the other hand, when the average pore diameter exceeds 400 nm, the amount of silver falling into the pores increases, so that image clarity cannot be obtained.
However, when the average pore diameter is more than 200 nm and less than or equal to 400 nm, the ink solution containing silver is efficiently absorbed, and a printed matter having high image clarity and excellent metallic luster is obtained immediately after printing. Can do.

The porous average thickness is 5 μm or more and 30 μm or less, the lower limit is preferably 10 μm or more, more preferably 20 μm or more, and the upper limit is preferably 25 μm or less.
When the average thickness is less than 5 μm, a vehicle such as a solvent or a dispersant cannot be absorbed and image clarity cannot be obtained. On the other hand, when the average thickness exceeds 30 μm, not only the smoothness is lowered but the metallic luster and image clarity are not obtained, and the porous material may be peeled off from the recording medium.
However, when the average thickness is 5 μm or more and 30 μm or less, when an ink containing silver is applied, a vehicle such as a solvent and a dispersant can be efficiently absorbed, and the recording property is excellent in image clarity and metallic luster. You can get things.

  The porous pore diameter and the average thickness of the porous are the concentration of the solid content (for example, silica, alumina, etc.) contained in the porous forming material, the application of the porous forming material applied to the recording medium. It can be controlled by the amount.

<< Porosity-forming material >>
The porous material is not particularly limited as long as it can be applied to a recording medium and can form a porous material having an average pore diameter of more than 200 nm and not more than 400 nm and an average thickness of not less than 5 μm and not more than 30 μm. Has silica or alumina which is excellent in paper, polyethylene terephthalate (PET), resin-based substrates such as vinyl chloride, film formability on non-absorbent recording media, film uniformity, adhesion, and safety Is preferred. Although the recording medium marketed in the state in which the coating layer containing a silica or an alumina was provided may be formed, the porous material of the present invention is formed by providing the porous forming material on the coating layer. Can do.
The porous forming material can control physical properties such as viscosity, surface tension, and the like by the particle size of the material, which is a solid content such as alumina and silica, solvent type, surfactant, and the like. By controlling the physical properties of the porous forming material, for example, it is possible to prepare the porous forming material having an appropriate discharge property for discharging from an inkjet head.
About the material which forms the said porous, for example, an alumina, a silica, etc., it can detect by a fluorescent X ray analysis.
The porous material preferably contains at least one of silica and alumina, and if necessary, a solvent, a resin, a surfactant, an antifoaming agent, an antiseptic / antifungal agent, a rust preventing agent, pH. A regulator or the like may be added.
Examples of the solvent include organic solvents and water.
In addition, it is possible to use a commercially available silica or alumina sol or gel coating material.

<< Silica or alumina coating agent >>
The shape of silica or alumina as a coating agent may be spherical, or may be one in which particles are connected in a beaded manner or branched by a special treatment (for example, a chain shape, a pearl necklace shape, etc.).
Further, those whose surface is modified with ions or compounds such as ammonia, calcium and alumina can also be used.
Examples of the silica coating agent include Snowtex S, Snowtex N, Snowtech UP, ST-XS, ST-O, ST-C, and ST-20 (all manufactured by Nissan Chemical Co., Ltd.), Cataloid SI-350. , Cataloid SI-30, SN, SA, S-20L, S-20H, S-30L, S-30H (above, manufactured by Catalytic Chemical Industry Co., Ltd.), Aerosil 200, 200V, 200CF, 300 (above, Nippon Aerosil Co., Ltd.) Company-made). Examples of the alumina coating agent include alumina clearsol 5S, F1000, F3000, and A2 (manufactured by Kawaken Fine Chemical Co., Ltd.).

As the porous forming method, it is preferable to use an inkjet method, but other methods include, for example, blade coating method, gravure coating method, bar coating method, roll coating method, dip coating method, curtain coating method, slide coating method, and die coating. Porous formation is possible by applying a porous forming material onto a recording medium using a method, a spray coating method, or the like.
By forming a porous layer by an ink jet method, the porous layer can be selectively formed only at a portion where a metallic luster is desired (a portion where a silver ink is applied), and thus the production efficiency is high. When the porous material is applied by an ink jet method, a characteristic droplet mark is observed on the recorded material by observing an SEM image of the recorded material. For example, a droplet mark 501 as shown in FIG. 3 is observed.
In forming the porous material, it may be naturally dried at room temperature, or may be heated to promote drying. A preferable range of the drying temperature is preferably 30 ° C. to 80 ° C., and 40 ° C. to 70 ° C. is more preferable in terms of both the drying property of the porous forming material and the prevention of thickening of the liquid component near the nozzle of the head. .

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

A polyol compound having 8 or more carbon atoms and a glycol ether compound are also preferably used.
Specific examples of the polyol compound having 8 or more carbon atoms include 2-ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, and the like.
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. Examples of ethers include polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.

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

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

<< Water >>
Water is the main medium of the material for forming a porous material, and preferred water is ion exchange water, ultrafiltration water, reverse osmosis water, distilled water, etc. for the purpose of reducing ionic impurities as much as possible. Pure water or ultrapure water can be used. Further, it is preferable to use water sterilized by ultraviolet irradiation or addition of hydrogen peroxide because generation of mold and bacteria can be prevented when the porous forming material is stored for a long period of time.
The content of water in the porous forming material is not particularly limited and can be appropriately selected according to the purpose. However, the environmental load can be reduced, and other components can be included. % By mass or less is preferable, and 20% by mass or more and 60% by mass or less is more preferable.

<< Resin >>
The type of the resin is not particularly limited and may be appropriately selected depending on the purpose. For example, urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene resin Examples thereof include butadiene resins, vinyl chloride resins, acrylic styrene resins, and acrylic silicone resins. You may use the resin particle which consists of these resin. It is possible to obtain a porous material by mixing resin particles with a material such as a coloring material or an organic solvent in a resin emulsion state in which water is used as a dispersion medium. As said resin particle, what was synthesize | combined suitably may be used and a commercial item may be used. Moreover, these may be used individually by 1 type, or may be used in combination of 2 or more types of resin particles.

  A water-soluble resin is also preferably used as the resin. The water-soluble resin is not particularly limited, and examples thereof include proteins such as gelatin and casein, natural rubber such as gum arabic, glucooxide such as saponin, cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxymethylcellulose, lignin sulfone. Acid, natural polymers such as shellac, polyacrylate, polyacrylamide, styrene-acrylic acid copolymer salt, vinylnaphthalene-acrylic acid copolymer salt, styrene-maleic acid copolymer salt, vinylnaphthalene-maleic acid Acid copolymer salt, sodium salt of β-naphthalenesulfonic acid holymarin condensate, ionic polymer such as polyphosphoric acid, polyvinyl alcohol, polyvinyl butyral, polyethylene glycol, polypropylene glycol, polyethyleneoxy , Polyvinyl methyl ether, polyethylene imine.

  The content of the resin is preferably 0.05% by mass or more and 10.0% by mass or less, and more preferably 0.3% by mass or more and 4.0% by mass or less with respect to the total amount of the porous forming material. Within this range, the function of the resin is suitably exhibited, and good scratch resistance can be obtained. Moreover, it is preferable because a suitable metallic luster is also obtained.

<< Surfactant >>
As the surfactant, any of silicone surfactants, fluorine surfactants, amphoteric surfactants, nonionic surfactants and anionic surfactants can be used.
There is no restriction | limiting in particular in silicone type surfactant, According to the objective, it can select suitably. Among them, those that do not decompose even at high pH are preferable, and examples thereof include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane. Those having an oxyethylene group or a polyoxyethylene polyoxypropylene group are particularly preferred because they exhibit good properties as an aqueous surfactant. In addition, as the silicone surfactant, a polyether-modified silicone surfactant can be used, and examples thereof include a compound in which a polyalkylene oxide structure is introduced into the side chain of the Si portion of dimethylsiloxane.
Examples of the fluorosurfactant 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. Polyoxyalkylene ether polymer compounds are particularly preferred because of their low foaming properties. Examples of the perfluoroalkyl sulfonic acid compound include perfluoroalkyl sulfonic acid, perfluoroalkyl sulfonate, and the like. Examples of the perfluoroalkylcarboxylic acid compound include perfluoroalkylcarboxylic acid and perfluoroalkylcarboxylate. Examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain include 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. As counter ions of salts in these fluorosurfactants, 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) ₃ etc. are mentioned.
Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine.
Nonionic surfactants include, for example, polyoxyethylene alkylphenyl ether, polyoxyethylene alkyl ester, polyoxyethylene alkylamine, polyoxyethylene alkylamide, polyoxyethylene propylene block polymer, sorbitan fatty acid ester, polyoxyethylene sorbitan Examples include fatty acid esters and ethylene oxide adducts of acetylene alcohol.
Examples of the anionic surfactant include polyoxyethylene alkyl ether acetate, dodecylbenzene sulfonate, laurate, polyoxyethylene alkyl ether sulfate salt, and the like.
These may be used alone or in combination of two or more.

The silicone surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, side Since both ends of the chain are modified with polydimethylsiloxane, a polyether-modified silicone surfactant having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group exhibits good properties as an aqueous surfactant. preferable.
As such a surfactant, an appropriately synthesized product or a commercially available product may be used. Commercially available products can be obtained from, for example, Big Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Toray Dow Corning Silicone Co., Ltd., Nippon Emulsion Co., Ltd., and Kyoeisha Chemical Co., Ltd.
There is no restriction | limiting in particular as said polyether modified silicone surfactant, According to the objective, it can select suitably, For example, the polyalkylene oxide structure represented by the following general formula (S-1) is dimethylpolyethylene. Examples thereof include those introduced into the side chain of Si part of siloxane.
Formula (S-1)
(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.)
A commercial item can be used as said polyether modified silicone type surfactant, For example, KF-618, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS- 1906EX (Japan 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 (Bic Chemie Corporation), TSF4440, TSF4452, TSF4453 (Toshiba Silicone Corporation), etc. are mentioned.

As the fluorine-based surfactant, a fluorine-substituted compound having 2 to 16 carbon atoms is preferable, and a fluorine-substituted compound having 4 to 16 carbon atoms is more preferable.
Examples of the fluorine-based surfactant include perfluoroalkyl phosphate compounds, perfluoroalkylethylene oxide adducts, polyoxyalkylene ether polymer compounds 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 of its low foaming property, and in particular, fluorine-based compounds represented by the general formulas (F-1) and (F-2) A surfactant is preferred.
Formula (F-1)
In the compound represented by the general formula (F-1), m is preferably an integer of 0 to 10 and n is preferably an integer of 0 to 40 in order to impart water solubility.
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 general formula (F-2), Y is H, or CmF _{2m + 1} , m is an integer of 1 to 6, or CH ₂ CH (OH) CH ₂ —CmF _{2m + 1,} where m is 4 to 6. An integer, or CpH _{2p + 1} , p is an integer of 1-19. n is an integer of 1-6. a is an integer of 4-14.
A commercial item may be used as said fluorosurfactant. As this commercial item, for example, Surflon S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145 (all manufactured by Asahi Glass Co., Ltd.); Fullrad FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431 (all manufactured by Sumitomo 3M Limited); Megafac F-470, F -1405, F-474 (all manufactured by Dainippon Ink & Chemicals, Inc.); 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 Chemours Co., Ltd.); FT-110, FT- 50, 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 (Omnova Co., Ltd.), Unidyne DSN-403N (Daikin Kogyo Co., Ltd.), etc. Among them, good printing quality, particularly color development, paper permeability, wettability, and leveling are significantly improved. FS-3100, FS-34, FS-300 manufactured by Chemours Co., Ltd., FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Co., Ltd. Polyfox PF-151N manufactured by Omninova Co., Ltd. and Unidyne DSN-40 manufactured by Daikin Industries, Ltd. N is particularly preferred.

  The content of the surfactant in the porous material is not particularly limited and may be appropriately selected depending on the intended purpose. However, the wettability and ejection stability are excellent, and the image quality is improved. From the point, 0.001% by mass to 5% by mass is preferable, and 0.05% by mass to 5% by mass is more preferable.

<<< antifoaming agent >>>
There is no restriction | limiting in particular as an antifoamer, For example, a silicone type antifoamer, a polyether type | system | group antifoamer, a fatty-acid ester type | system | group antifoamer etc. are mentioned. These may be used alone or in combination of two or more. Among these, a silicone type antifoaming agent is preferable from the viewpoint of excellent foam breaking effect.

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

<< rust preventive agent >>
There is no restriction | limiting in particular as a rust preventive agent, For example, acidic sulfite, sodium thiosulfate, etc. are mentioned.

<< pH adjuster >>
The pH adjuster 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.

There is no restriction | limiting in particular as a physical property of the said porous formation material, According to the objective, it can select suitably, For example, it is preferable that a viscosity, surface tension, pH, etc. are the following ranges.
The viscosity at 25 ° C. of the porous forming material is preferably 5 mPa · s or more and 30 mPa · s or less, from the viewpoint that printing density and character quality are improved and good discharge properties are obtained. 25 mPa · s or less is more preferable. Here, for the viscosity, for example, a rotary viscometer (manufactured by Toki Sangyo Co., Ltd., RE-80L) can be used. Measurement conditions are 25 ° C., standard cone rotor (1 ° 34 ′ × R24), sample liquid amount 1.2 mL, rotation speed 50 rpm, and measurement is possible for 3 minutes.
As the surface tension of the porous forming material, the porous forming material is preferably leveled on the recording medium, and the drying time of the porous forming material is shortened. Is preferable, and 32 mN / m or less is more preferable.
The pH of the porous material 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.

<Silver ink application step and silver ink application means>
In the silver ink application step, the average pore diameter formed by applying the porous forming material on the recording medium is more than 200 nm and not more than 400 nm, and the average thickness is 5 μm or more and 30 μm or less. , A step of applying silver ink, which is performed by silver ink applying means.
As an example of the silver ink application step, for example, the silver ink can be applied to the porous surface using a bar coater or an inkjet head.
Examples of the silver ink applying unit include a bar coater and an inkjet head.
The silver ink application step is preferably performed continuously with the porous formation step. When the silver ink application step and the porous formation step are successively performed, the silver ink application step and the porous formation step may be performed with separate devices, but with the same device. It is preferable. By using the same apparatus, it is possible to appropriately improve the productivity and control the landing of the silver ink on the porous material, thereby obtaining a recorded matter with better metallic luster and image clarity.

<< Ink containing silver >>
The ink containing silver (hereinafter also referred to as silver ink) contains silver, and further contains a polymer dispersant, an organic solvent, water, a resin, a surfactant, an antifoaming agent, antiseptic, as necessary. You may add additives, such as a glaze, a rust preventive agent, and a pH adjuster. In addition, the silver ink can be prepared as a silver ink using water and a solvent having a moisturizing function, and the additive can be added as necessary. Silver is a metal having high whiteness among various metals, and is preferable because various metal colors can be realized by combining with other color inks. Also, silver is stable in water because of its low reactivity with water. As a result, it is possible to develop a water-based glitter ink that can reduce the environmental load, which is preferable.
The organic solvent, the water, the resin, the surfactant, the antifoaming agent, the antiseptic / antifungal agent, and the pH adjuster are the same as the organic solvent in the porous forming material of the present invention. Can be used.
In addition, the effect of the additive, the content of the additive, and the physical properties of the silver ink can be obtained in the silver ink as well as the porous forming material of the present invention.

<< Silver >>
The silver can improve the image clarity and metallic luster of the recorded matter. As the silver, silver particles are preferable. The number average particle diameter of the silver particles is preferably 15 nm or more and 100 nm or less, and more preferably 30 nm or more and 60 nm or less. When the number average particle diameter is 15 nm or more, silver enters into the porous material, and a large number of nanoparticles are present on the lowermost surface of the recorded material, thereby reflecting the color (yellow) of silver nanoparticles. By doing, it can suppress suitably that color becomes unnatural and can improve metal luster favorably. Further, when the number average particle diameter is 100 nm or less, the discharge stability can be improved without silver in the ink precipitating over time.
The number average particle diameter can be measured with a laser diffraction particle size distribution analyzer. As the laser diffraction particle size distribution measuring device, for example, a particle size distribution meter (for example, “Microtrac UPA”, manufactured by Nikkiso Co., Ltd.) based on the dynamic light scattering method can be used.
The silver content in the silver ink is preferably 1.0% by mass or more and 15.0% by mass or less, and more preferably 2.5% by mass or more and 10% by mass or less based on the total amount of the ink. When the content is 1.0% by mass or more, high image clarity and metallic luster can be exhibited. Further, when the content is 15.0% by mass or less, good silver dispersion stability, storage stability of the silver ink, and ejection stability can be obtained.

<< Silver colloid liquid >>
Silver is preferably dispersed in an aqueous dispersion medium as a silver colloid having a protective colloid attached to its surface. Thereby, the dispersibility of silver in an aqueous dispersion medium is particularly excellent, and the storage stability of the silver ink is remarkably improved. The silver colloid may be prepared by any method, and can be obtained, for example, by preparing a solution containing silver ions and reducing the silver ions with a reducing agent in the presence of the protective colloid. (For example, refer to JP 2006-299329 A). When a silver colloid is produced by these methods, the dispersion stability of silver particles is further improved by adding a surfactant or the like to the aqueous solution at an arbitrary time before and after the reduction reaction. The protective colloid is not particularly limited as long as it is an organic substance that plays a role in protecting the silver surface, but an organic compound having a carboxyl group and a polymer dispersant are preferred, and any one of them may be used alone, Two or more types may be used in combination, but the combination is more preferable because a synergistic effect is obtained.

<< Organic compound having carboxyl group >>
The number of carboxyl groups of the organic compound having a carboxyl group is not particularly limited as long as it is 1 or more per molecule. For example, 1 to 10 is preferable, 1 to 5 is more preferable, and 1 to 3 is more preferable. In the organic compound having a carboxyl group, some or all of the carboxyl groups may form a salt (for example, a salt with an amine, a metal salt, or the like). In particular, in the present invention, a carboxyl group (particularly, all carboxyl groups) is an organic compound that does not form a salt [particularly a salt with a basic compound (such as a salt with an amine or an amine salt). An organic compound having a carboxyl group) can be preferably used.

  The organic compound having a carboxyl group is not particularly limited as long as it has a carboxyl group, and can be appropriately selected according to the purpose. The functional group other than the carboxyl group (or the arrangement with respect to the metal compound or metal nanoparticles) can be selected. May have a coordination group or the like.

Examples of such a functional group (or coordinating group) other than a carboxyl group include a group (or a functional group) having at least one heteroatom selected from a halogen atom, a nitrogen atom, an oxygen atom, and a sulfur atom. ) Or a group (ammonium base or the like) that forms these salts. These functional groups may be used alone or in combination of two or more organic compounds having a carboxyl group.
Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.
Examples of the group having a nitrogen atom include an amino group, a substituted amino group (dialkylamino group and the like), an imino group (-NH-), a nitrogen ring group (a 5- to 8-membered nitrogen ring group such as a pyridyl group, and a carbazole group. , Morpholinyl group, etc.), amide group (—CON <), cyano group, nitro group and the like.
Examples of the group having an oxygen atom include a hydroxyl group, an alkoxy group (for example, an alkoxy group having 1 to 6 carbon atoms such as a methoxy group, an ethoxy group, a propoxy group, and a butoxy group), a formyl group, and a carbonyl group (—CO -), Ester groups (-COO-), oxygen ring groups (5- to 8-membered oxygen ring groups such as tetrahydropyranyl group) and the like.
Examples of the group having a sulfur atom include a thio group, a thiol group, a thiocarbonyl group (—SO—), an alkylthio group (an alkylthio group having 1 to 4 carbon atoms such as a methylthio group and an ethylthio group), a sulfo group, A sulfamoyl group, a sulfinyl group (—SO ₂ —) and the like can be mentioned.

  The organic compound having a carboxyl group does not have a basic group (particularly an amino group, a substituted amino group, an imino group, or an ammonium base) that can form a salt with the carboxyl group among these functional groups. Preferably it is a compound.

  Typical organic compounds having a carboxyl group include carboxylic acids. Examples of such carboxylic acid include monocarboxylic acid, polycarboxylic acid, and hydroxycarboxylic acid (or oxycarboxylic acid).

Examples of the monocarboxylic acid include saturated aliphatic monocarboxylic acid, unsaturated aliphatic monocarboxylic acid, and aromatic monocarboxylic acid.
Examples of the saturated aliphatic monocarboxylic acid include carbon such as acetic acid, propionic acid, butyric acid, caprylic acid, caproic acid, hexanoic acid, capric acid, lauric acid, myristic acid, cyclohexanecarboxylic acid, dehydrocholic acid, and colanic acid. Examples thereof include aliphatic monocarboxylic acids having 1 to 34 carbon atoms (preferably aliphatic monocarboxylic acids having 1 to 30 carbon atoms).
Examples of the unsaturated aliphatic monocarboxylic acid include unsaturated aliphatic monocarboxylic acids having 4 to 34 carbon atoms such as oleic acid, erucic acid, linoleic acid, and abietic acid (preferably having 10 to 30 carbon atoms). Unsaturated aliphatic monocarboxylic acid).
Examples of the aromatic monocarboxylic acid include aromatic monocarboxylic acids having 7 to 12 carbon atoms such as benzoic acid and naphthoic acid.

Examples of the polycarboxylic acid include aliphatic saturated polycarboxylic acid, aliphatic unsaturated polycarboxylic acid, and aromatic polycarboxylic acid.
Examples of the aliphatic saturated polycarboxylic acid include aliphatic saturated polycarboxylic acids having 2 to 14 carbon atoms such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and cyclohexanedicarboxylic acid. Examples thereof include acids (preferably aliphatic saturated polycarboxylic acids having 2 to 10 carbon atoms).
Examples of the aliphatic unsaturated polycarboxylic acid include aliphatic unsaturated polycarboxylic acids having 4 to 14 carbon atoms such as maleic acid, fumaric acid, itaconic acid, sorbic acid and tetrahydrophthalic acid (preferably having 4 carbon atoms). And an aliphatic unsaturated polycarboxylic acid having 10 or less).
Examples of the aromatic polycarboxylic acid include aromatic polycarboxylic acids having 8 to 12 carbon atoms such as phthalic acid and trimellitic acid.

Examples of the hydroxycarboxylic acid include hydroxymonocarboxylic acid and hydroxypolycarboxylic acid.
Examples of the hydroxy monocarboxylic acid include aliphatic hydroxy monocarboxylic acid and aromatic hydroxy monocarboxylic acid.
Examples of the aliphatic hydroxy monocarboxylic acid include glycolic acid, lactic acid, oxybutyric acid, glyceric acid, 6-hydroxyhexanoic acid, cholic acid, deoxycholic acid, chenodeoxycholic acid, 12-oxochenodeoxycholic acid, glycocholic acid, lithocol. C2-C50 aliphatic hydroxymonocarboxylic acid (preferably C2-C34 aliphatic hydroxymonocarboxylic acid, such as acid, hyodeoxycholic acid, ursodeoxycholic acid, apocholic acid, taurocholic acid, etc. Preferred are aliphatic hydroxy monocarboxylic acids having 2 to 30 carbon atoms.
Examples of the aromatic hydroxymonocarboxylic acid include aromatic hydroxymonocarboxylic acids having 7 to 12 carbon atoms such as salicylic acid, oxybenzoic acid, and gallic acid.
Examples of the hydroxypolycarboxylic acid include aliphatic hydroxypolycarboxylic acids.
Examples of the aliphatic hydroxypolycarboxylic acid include aliphatic hydroxypolycarboxylic acids having 2 to 10 carbon atoms such as tartronic acid, tartaric acid, citric acid, and malic acid.

  The carboxylic acid may form a salt, and may be an anhydride, a hydrate or the like. Here, as described above, the carboxylic acid often does not form a salt (in particular, a salt with a basic compound such as a salt with an amine).

The organic compound which has the said carboxyl group may be used individually by 1 type, and may use 2 or more types together.
As the organic compound having a carboxyl group, hydroxycarboxylic acids such as aliphatic hydroxycarboxylic acids (aliphatic hydroxymonocarboxylic acids and aliphatic hydroxypolycarboxylic acids) are preferable.
The aliphatic hydroxycarboxylic acid is preferably an alicyclic hydroxycarboxylic acid (or a hydroxycarboxylic acid having an alicyclic skeleton).
The alicyclic hydroxycarboxylic acid (or hydroxycarboxylic acid having an alicyclic skeleton) is preferably an alicyclic hydroxycarboxylic acid having 6 to 34 carbon atoms such as cholic acid, and preferably having 10 to 34 carbon atoms. An alicyclic hydroxycarboxylic acid is more preferable, and an alicyclic hydroxycarboxylic acid having 16 to 30 carbon atoms is particularly preferable.

In addition, polycyclic aliphatic hydroxycarboxylic acids such as cholic acid, polycyclic aliphatic carboxylic acids such as dehydrocholic acid, and colanic acid have a bulky structure and suppress aggregation of silver particles. It is preferable because the effect is great.
Examples of the polycyclic aliphatic hydroxycarboxylic acid include a condensed polycyclic aliphatic hydroxycarboxylic acid, preferably a condensed polycyclic aliphatic hydroxycarboxylic acid having 10 to 34 carbon atoms, more preferably 14 or more carbon atoms. Examples thereof include 34 or less condensed polycyclic aliphatic hydroxycarboxylic acids, particularly preferably a condensed polycyclic aliphatic hydroxycarboxylic acid having 18 to 30 carbon atoms.
Examples of the polycyclic aliphatic carboxylic acid include a condensed polycyclic aliphatic carboxylic acid, preferably a condensed polycyclic aliphatic carboxylic acid having 10 to 34 carbon atoms, more preferably 14 to 34 carbon atoms. Examples thereof include condensed polycyclic aliphatic hydroxycarboxylic acids, particularly preferably condensed polycyclic aliphatic carboxylic acids having 18 to 30 carbon atoms.

  The number average molecular weight of the organic compound having a carboxyl group is preferably, for example, 1,000 or less, more preferably 800 or less, and even more preferably 600 or less. Further, the pKa value of the organic compound having a carboxyl group is, for example, preferably 1 or more, more preferably 2 or more, and further preferably 2 or more and 8 or less. The number average molecular weight can be measured, for example, by gel permeation chromatography (GPC).

<< Polymer dispersant >>
In the present invention, the protective colloid is constituted by combining the organic compound having a carboxyl group and a polymer dispersant. By constructing the protective colloid in such a combination, a silver colloid containing silver with extremely few coarse particles can be obtained. In particular, in the present invention, the combination of the specific protective colloids can increase the proportion of silver even though there are few coarse particles, and the storage stability of the silver colloid (or dispersion thereof) is also excellent.

Examples of the polymer dispersant include styrene resin, acrylic resin, water-soluble urethane resin, water-soluble acrylic urethane resin, water-soluble epoxy resin, water-soluble polyester resin, cellulose derivative, polyvinyl alcohol, polyalkylene glycol, natural Examples thereof include polymers, polyethylene sulfonates, and formalin condensates of naphthalene sulfonic acid. These may be used individually by 1 type and may use 2 or more types together.
Examples of the styrenic resin include styrene- (meth) acrylic acid copolymers and styrene-maleic anhydride copolymers.
Examples of the acrylic resin include methyl (meth) acrylate- (meth) acrylic acid copolymer.
Examples of the cellulose derivatives include alkyl celluloses such as nitrocellulose and ethyl cellulose, alkyl-hydroxyalkyl celluloses such as ethyl hydroxyethyl cellulose, hydroxyalkyl celluloses such as hydroxyethyl cellulose and hydroxypropyl cellulose, and celluloses such as carboxyalkyl cellulose such as carboxymethyl cellulose. And ethers.
Examples of the polyalkylene glycol include gelatin and dextrin.
Examples of the polyalkylene glycol include liquid polyethylene glycol and polypropylene glycol.

  As a typical polymer dispersant (amphiphilic polymer dispersant), a resin (or water-soluble resin, water-dispersible resin) containing a hydrophilic unit (or hydrophilic block) composed of a hydrophilic monomer. Is included.

Examples of the hydrophilic monomer include addition polymerization monomers such as a carboxyl group or acid anhydride group-containing monomer and a hydroxyl group-containing monomer, and condensation monomers such as alkylene oxide (ethylene oxide and the like).
Examples of the acid anhydride group-containing monomer include (meth) acrylic monomers such as acrylic acid and methacrylic acid, unsaturated polyvalent carboxylic acids such as maleic acid, and maleic anhydride.
Examples of the hydroxyl group-containing monomer include hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, vinylphenol, and the like.
As the condensation monomer, a hydrophilic unit may be formed by reaction with an active group such as a hydroxyl group (for example, the hydroxyl group-containing monomer).
As said hydrophilic monomer, you may form the hydrophilic unit individually by 1 type or in combination of 2 or more types.

  The polymer dispersant only needs to contain at least a hydrophilic unit (or hydrophilic block), and may be a homopolymer or a copolymer of a hydrophilic monomer (for example, polyacrylic acid or a salt thereof). Further, a copolymer of a hydrophilic monomer and a hydrophobic monomer may be used, such as the exemplified styrene resin and acrylic resin.

Examples of the hydrophobic monomer (nonionic monomer) include (meth) acrylic monomers such as (meth) acrylic acid esters; styrene monomers such as styrene, α-methylstyrene and vinyltoluene, α-carbon number 2 20 or less olefinic monomers, vinyl carboxylic acid ester monomers such as vinyl acetate and vinyl butyrate are listed. The hydrophobic monomer may constitute a hydrophobic unit either singly or in combination of two or more.
Examples of the (meth) acrylic acid ester include methyl (meth) acrylate, ethyl (meth) acrylate, (n-butyl) (meth) acrylate, 2-ethylhexyl (meth) acrylate, and (meth) acrylic. (Meth) acrylic acid having 1 to 20 carbon atoms such as lauryl acid, stearyl (meth) acrylate, alkyl (meth) acrylate such as cyclohexyl (meth) acrylate, (meth) acrylic acid phenyl (meth) ) Aryl acrylate, benzyl (meth) acrylate, aralkyl (meth) acrylate such as 2-phenylethyl (meth) acrylate, and the like.
Examples of the α-carbon number 2 to 20 olefin-based monomer include ethylene, propylene, 1-butene, isobutylene, 1-hexene, 1-octene, 1-dodecene and the like.

When the polymer dispersant is a copolymer (for example, a copolymer of a hydrophilic monomer and a hydrophobic monomer), the copolymer may be a random copolymer, an alternating copolymer, a block copolymer (for example, a hydrophilic composed of hydrophilic monomers). A copolymer composed of a block and a hydrophobic block composed of a hydrophobic monomer), a comb copolymer (or a comb graft copolymer), and the like.
The structure of the block copolymer is not particularly limited, and may be a diblock structure, a triblock structure (ABA type, BAB type), or the like. In the comb copolymer, the main chain may be composed of the hydrophilic block, the hydrophobic block, or the hydrophilic block and the hydrophobic block.

  As described above, the hydrophilic unit may be composed of a condensation block such as a hydrophilic block (polyalkylene oxide such as polyethylene oxide or polyethylene oxide-polypropylene oxide) composed of alkylene oxide (ethylene oxide or the like). it can.

The hydrophilic block (polyalkylene oxide or the like) and the hydrophobic block (polyolefin block or the like) may be bonded via a linking group such as an ester bond, an amide bond, an ether bond, or a urethane bond.
The bond may be formed, for example, by modifying a hydrophobic block (polyolefin or the like) with a modifying agent and then introducing a hydrophilic block.
Examples of the modifying agent include unsaturated carboxylic acid or its anhydride (such as (anhydrous) maleic acid), lactam or aminocarboxylic acid, hydroxylamine, diamine, and the like.

  In addition, a polymer obtained from a monomer having a hydrophilic group such as a hydroxyl group or a carboxyl group (the hydroxyalkyl (meth) acrylate or the like) is reacted (or bonded) with the condensed hydrophilic monomer (ethylene oxide or the like). By doing so, a comb-type copolymer (comb-type copolymer having a main chain composed of a hydrophobic block) may be formed.

Furthermore, the balance between hydrophilicity and hydrophobicity may be adjusted by using a hydrophilic nonionic monomer as a copolymerization component.
Examples of such components include monomers having alkyleneoxy (particularly ethyleneoxy) units such as 2- (2-methoxyethoxy) ethyl (meth) acrylate and polyethylene glycol monomethacrylate (for example, a number average molecular weight of about 200 to 1,000). An oligomer etc. can be illustrated.
Further, the balance between hydrophilicity and hydrophobicity may be adjusted by modifying (for example, esterifying) a hydrophilic group (such as a carboxyl group).

  The polymer dispersant may have a functional group. Examples of such functional groups include acid groups (or acidic groups such as carboxyl groups (or acid anhydride groups), sulfo groups (sulfonic acid groups), etc.), hydroxyl groups, and the like. These functional groups may be possessed by the polymer dispersant alone or in combination of two or more.

Of these functional groups, the polymer dispersant preferably has an acid group, particularly a carboxyl group.
When the polymer dispersant has an acid group (carboxyl group, etc.), at least a part or all of the acid group (carboxyl group, etc.) forms a salt (a salt with an amine, a metal salt, etc.). In particular, in the present invention, an acid group such as a carboxyl group (particularly, all carboxyl groups) is a salt [particularly a salt with a basic compound (a salt with an amine or an amine salt)]. A polymer dispersant that is not formed [that is, a polymer dispersant having a free acid group (particularly a carboxyl group)] can be suitably used.

  The acid value of the polymer dispersant having an acid group (particularly carboxyl group) is, for example, preferably 1 mgKOH / g to 100 mgKOH / g, more preferably 3 mgKOH / g to 90 mgKOH / g, and more preferably 5 mgKOH / g to 80 mgKOH / g. g or less is more preferable, and 7 mgKOH / g or more and 70 mgKOH / g or less is particularly preferable. In the dispersant polymer having an acid group, the amine value may be 0 mgKOH / g (or almost 0 mgKOH / g).

In the polymer dispersant, the position of the functional group as described above is not particularly limited, and may be a main chain, a side chain, or a main chain and a side chain. Also good.
Such a functional group may be, for example, a hydrophilic monomer or a functional group derived from a hydrophilic unit (for example, a hydroxyl group), or a copolymerizable monomer having a functional group (for example, maleic anhydride). It can also be introduced into the polymer by copolymerization.
The polymer dispersant may be used alone or in combination of two or more.
As the polymer dispersant, a polymer dispersant (polymer pigment dispersant) described in JP-A No. 2004-207558 may be used.
The polymer dispersant may be a synthesized one or a commercially available product.

Specific examples of commercially available polymer dispersants (or dispersants composed of at least an amphiphilic dispersant) include Solsperse 13240, Solsperse 13940, Solsperse 32550, Solsperse 31845, Solsperse 24000, Solsperse 26000, Solsperse series such as Solsperse 27000, Solsperse 28000, Solsperse 41090 [manufactured by Avicia Co., Ltd.]; Dispersic 160, Dispersic 161, Dispersic 162, Dispersic 163, Dispersic 164, Dispersic 166, Dispersic 170, Dispersic 180, Dispersic 182, Dispersic 184, Dispersic 190, Dispersic 191, Dispersibit 192, Disperbic 193, Disperbic 194, Disperbic 2001, Disperbic 2050 and other Dispersic series [manufactured by BYK Chemie Co., Ltd.]; -1,502, EFKA-4540, EFKA-4550, polymer 100, polymer 120, polymer 150, polymer 400, polymer 401, polymer 402, polymer 403, polymer 450, polymer 451, polymer 452, polymer 453 [manufactured by EFKA Chemical Co., Ltd.] Ajisper series such as Ajisper PB711, Ajisper PAl11, Ajisper PB811, Ajisper PB821, Ajisper PW911 [Ajinomoto Co., Inc. Floren series such as Floren DOPA-158, Floren DOPA-22, Floren DOPA-17, Floren TG-700, Floren TG-720W, Floren-730W, Floren-740W, Floren-745W [manufactured by Kyoeisha Chemical Co., Ltd.]; Examples include John Crill series [manufactured by Johnson Polymer Co., Ltd.] such as Kuril 678, John Crill 679 and John Crill 62.
Among these, polymer dispersants having acid groups include Dispersic 190, Dispersic 194, and the like.
The number average molecular weight of the polymer dispersant is, for example, preferably 1,500 to 100,000, more preferably 2,000 to 80,000, still more preferably 3,000 to 50,000, and particularly preferably 7, 000 to 20,000.
In recent years, colloidal silver liquids are commercially available from a plurality of manufacturers, and can be prepared into inks by using the commercially available products by the preparation methods described above.

<Color ink application process and color ink application means>
The color ink application step is a step of applying a color ink containing a color material to a recording medium, and is performed by a color ink application unit.
As an example of the color ink application step, for example, the color ink can be applied to the recording medium using a bar coater or an inkjet head.
Examples of the color ink applying unit include a bar coater and an inkjet head.

<< Color ink >>
The color ink contains a color material other than silver, and may further contain a solvent, a resin, a surfactant, an antifoaming agent, an antiseptic / antifungal agent, a rust preventing agent, a pH adjusting agent, and the like as necessary.
The color ink is an ink containing a color material other than silver and is clearly different from a silver ink containing silver. Examples of the color ink include achromatic ink such as black ink and white ink, and chromatic ink such as yellow ink, magenta ink, and cyan ink.
By applying the color ink, various metallic colors other than silver can be reproduced.
Examples of the solvent include organic solvents and water.
The organic solvent, the water, the resin, the surfactant, the antifoaming agent, the antiseptic / antifungal agent, and the pH adjuster are the same as the organic solvent in the porous forming material of the present invention. Can be used.
In addition, the effects of the additive, the content of the additive, and the physical properties of the color ink are also obtained in the color ink as in the case of the porous forming material of the present invention.

<< Color material >>
The color material is not particularly limited, and pigments and dyes can be used.
An inorganic pigment or an organic pigment can be used as the pigment. These may be used alone or in combination of two or more. A mixed crystal may be used.
Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy color pigments such as gold and silver, and metallic pigments.
Carbon black produced by known methods such as contact method, furnace method, thermal method in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow as inorganic pigments Can be used.
Organic pigments include azo pigments, polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments). Dye chelates (for example, basic dye type chelates, acidic dye type chelates), nitro pigments, nitroso pigments, aniline black, and the like can be used. Of these pigments, those having good affinity with the solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
Specific examples of the pigment include black for carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11). And organic pigments such as metals such as titanium oxide and aniline black (CI Pigment Black 1).
Further, for color use, 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 (Permanent Red 2B (Ca)), 48: 3, 48: 4, 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Carmine 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Bengara), 104, 105, 106, 108 (Cadmium Red), 112, 114, 122 (quinacridone magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. I. Pigment violet 1 (rhodamine lake), 3, 5: 1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15: 1, 15: 2, 15: 3, 15: 4 (phthalocyanine blue), 16, 17: 1, 56, 60, 63, C.I. I. Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc.
The dye is not particularly limited, and an acid dye, a direct dye, a reactive dye, and a basic dye can be used. One kind may be used alone, or two or more kinds may be used in combination.
Examples of the dye include C.I. I. Acid Yellow 17, 23, 42, 44, 79, 142, C.I. I. Acid Red 52, 80, 82, 249, 254, 289, C.I. I. Acid Blue 9, 45, 249, C.I. I. Acid Black 1, 2, 24, 94, C.I. I. Food Black 1, 2, C.I. I. Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, 173, C.I. I. Direct Red 1, 4, 9, 80, 81, 225, 227, C.I. I. Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, C.I. I. Directed 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, and 35 are mentioned.

  The content of the color 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 improvement in image density, good fixability, and ejection stability. It is as follows.

In order to obtain an ink by dispersing a pigment, a method of introducing a hydrophilic functional group into the pigment to form a self-dispersing pigment, a method of coating the surface of the pigment with a resin and dispersing, a dispersing agent is used. Method, etc.
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. Is mentioned.
As a method for coating the surface of the pigment with a resin and dispersing it, a method in which the pigment is included in microcapsules and dispersible in water can be mentioned. This can be paraphrased as a resin-coated pigment. In this case, it is not necessary that all pigments blended in the ink are coated with a resin, and within a range where the effects of the present invention are not impaired, uncoated pigments and partially coated pigments are dispersed in the ink. May be.
Examples of the method of dispersing using a dispersant include a method of dispersing using a known low-molecular type dispersant or high-molecular type dispersant represented by a surfactant.
As the dispersant, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, or the like can be used depending on the pigment.
RT-100 (nonionic surfactant) manufactured by Takemoto Oil & Fat Co., Ltd. and naphthalenesulfonic acid Na formalin condensate can also be suitably used as a dispersant.
A dispersing agent may be used individually by 1 type, or may use 2 or more types together.

<< 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 pigment, other water, a dispersant and the like into a pigment dispersion and mixing materials such as water and an organic solvent.
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. For dispersion, a disperser may be used.
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 maximum number because the pigment dispersion stability is good and the image quality such as ejection stability and image density is also high. 500 nm or less is preferable and 20 nm or more and 150 nm or less are more preferable. The particle size of the pigment can be measured using a particle size analyzer (Nanotrack Wave-UT151, manufactured by Microtrack 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% by mass. % To 50% by mass is preferable, and 0.1% to 30% by mass is more preferable.
The pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifugal separator or the like, if necessary.

<< Printing layer containing silver >>
The printing layer containing silver is mainly composed of silver, and water, a solvent, amines, and a dispersant contained in the silver ink may remain. Furthermore, the printing layer containing silver preferably contains a resin, and the scratch resistance and metallic luster of the recorded matter are improved.
As content of the said resin, 0.2 mass% or more and 50.0 mass% or less are preferable with respect to the printing layer whole quantity containing the said silver, and 1.0 mass% or more and 10.0 mass% or less are more preferable. When the content is 0.2% by mass or more and 50.0% by mass or less, the function of the resin is suitably exhibited, good scratch resistance can be obtained, and suitable metallic luster can also be obtained. .
The printed layer containing silver is preferably formed on the porous material of the present invention having an average pore diameter of more than 200 nm and not more than 400 nm and an average thickness of not less than 5 μm and not more than 30 μm.

-Layer thickness of printing layer containing silver-
The layer thickness of the printing layer containing silver is the layer thickness after drying, and is the average layer thickness of the printing layer containing silver. The range of the thickness of the print layer containing silver is preferably in the range of 50 nm to 300 nm, and a recorded matter excellent in metallic luster and image clarity can be obtained. In the present invention, the surface of the printing layer is referred to as “printing surface”. When it is 50 nm or more and 300 nm or less, the brown color tone derived from plasmon absorption as the metal particles is low, and the metallic luster and image clarity are improved. Further, the porous material can immediately absorb the ink vehicle containing silver, and the metallic luster and image clarity are improved. It should be noted that a layer thickness of at least one silver is necessary, and the interaction between particles is increased in the lateral direction in which the particles are arranged, and the original metal-like image clarity can be obtained. Further, in the range within the particle diameter of 8 silver particles in the vertical direction, the porous ink is immediately absorbed and adsorbed by the ink vehicle containing silver, and a printed surface excellent in metallic luster and image clarity can be obtained.

-About the value of image clarity (2mm) specified in JIS H8866-2-
In the present invention, the “image clarity value” means the image clarity value obtained by the image clarity measurement method defined in JIS-H8686. Specifically, an optical device that detects reflected light (light receiving angle 45 degrees) applied to the measurement target surface through a slit at an angle of 45 degrees through a moving optical comb, and a wave of the detected light amount as a waveform The image clarity value C is obtained from the fluctuation waveform of the amount of light detected through the optical comb using the image clarity measurement device configured with the measuring device for storing.
Cl (n) = M−m / M + m × 100
Here, Cl (n) is the image clarity value (%) when the optical comb width is n (mm), M is the maximum wave height when the optical comb width is n (mm), and m is the optical comb width. Indicates the minimum wave height when n is (mm).
In the present invention, the Suga tester ICM-1 type is used as the image clarity measuring apparatus, and the optical comb width n is 2.0 mm.
In order to have a high image clarity in which the opposite object is reflected, the value of image clarity (2 mm) is preferably 5 or more, more preferably 30 or more. Although it is the upper limit for image clarity, since the maximum value is 98 even if it has a high mirror surface where a real image is reflected, the upper limit value is 98.

-About b * values-
In the present invention, the b * value is preferably −7 to +4 in order to ensure high image clarity and to secure a silver print surface. As the b * value goes to the minus side, the bluish color becomes stronger. Conversely, as the b * value goes to the plus side, the yellowish color becomes stronger. When the yellow color becomes stronger, the silver-containing ink of the present invention approaches gold and exceeds +4. When the b * value is less than -7, the bluish color becomes strong and the color tone is different from silver. About the measuring method of b * value, it can measure simply with a spectrocolorimeter.

<< Printing layer containing color material other than silver ink >>
The average thickness of a printing layer (color ink printing layer) containing a color material other than the silver ink is preferably 1 nm to 300 nm, and more preferably 2 nm to 250 nm. In particular, it is preferable not to conceal the silver color when toning with silver, and the average thickness at that time is particularly preferably 3 nm or more and 100 nm or less. If the color is adjusted within this range, a colored metallic image can be obtained, and a printing surface with good texture in both image clarity and color tone can be obtained. As the order of toning, it is preferable that after the printing with silver ink, the color ink is printed later on the silver ink printing section to perform the toning.

<< Method for measuring layer thickness of printed layer >>
The printed material is cut and the cross section thereof is observed with a microscope such as an optical microscope, a laser microscope, an SEM, or a transmission electron microscope (also referred to as a TEM) to include a printed layer containing silver and a color material other than silver ink. The layer thickness of the printed layer can be measured.

<< Recording medium >>
The recording medium is not particularly limited as long as a porous material having an average pore diameter of more than 200 nm and not more than 400 nm and an average thickness of 5 μm to 30 μm can be formed on the surface. Plain paper, glossy paper, special paper, cloth, and the like can be used, but good image formation is possible even with a non-permeable substrate. A receiving layer (such as a porous layer) may or may not be formed on the surface of the recording medium in advance.
In particular, the present invention is suitable for media in that an image excellent in image clarity and metallic luster can be formed on the non-permeable substrate which is not usually formed with an ink receiving layer such as a porous layer. There is an effect that it is excellent.
The non-permeable base material is a base material having a surface with low water permeability and absorbability, and includes materials that do not open to the outside even if there are many cavities inside, more quantitatively. In the Bristow method, the water absorption amount from the start of contact to 30 msec ^1/2 is 10 mL / m ² or less.
As said non-permeable base material, plastic films, such as a vinyl chloride resin film, a polyethylene terephthalate (PET) film, a polypropylene film, a polyethylene film, a polycarbonate film, can be used conveniently, for example. This is because a plastic film usually does not have a porous surface, and it is difficult to obtain the glossiness and image clarity of silver ink, so that the effects of the present invention are remarkably obtained.
The recording medium is not limited to one used as a general recording medium, and wallpaper, flooring, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather, and the like can be used as appropriate. Moreover, ceramics, glass, metal, etc. can also be used by adjusting the structure of the path | route which conveys a recording medium.

  A commercially available product can be used as the recording medium having a porous structure in advance. Examples of the commercially available products include IJ film RM-1GP01 (manufactured by Ricoh Co., Ltd., porous average pore size: 230 nm), NB-WF-3GF100 (porous average pore size: 210 nm), NB-RC-3GR120 ( Porous average pore size: 250 nm) (Mitsubishi Paper Co., Ltd.) PT-201A420 (porous average pore size: 270 nm), SD-101A450 (porous average pore size: 250 nm), GL-101A450 (porous average pore size) : 240 nm), GP501A450 (porous average pore size: 250 nm), SP-101A450 (porous average pore size: 210 nm), PT-101A420 (porous average pore size: 240 nm), PR101 (porous average pore size: 270 nm) ) (Manufactured by Canon Inc.), EJK-QTNA450 (porous Uniform pore size: 200 nm), EJK-EPNA450 (porous average pore size: 210 nm), EJK-CPNA450 (porous average pore size: 220 nm), EJK-RCA450 (porous average pore size: 240 nm), EJK-CGNA450 (porous) Average pore size: 190 nm), EJK-GANA450 (porous average pore size: 180 nm), EJK-NANA450 (porous average pore size: 170 nm), EJK-EGNA450 (porous average pore size: 200 nm) (ELECOM Co., Ltd.) Manufactured), WPA455VA (porous average pore size: 200 nm), WPA450PRM (porous average pore size: 210 nm), G3A450A (porous average pore size: 220 nm), G3A450A (porous average pore size: 210 nm), WPA420HIC (porous) Quality average (Diameter: 280 nm) (manufactured by FUJIFILM Corporation), KA420SCKR (porous average pore diameter: 240 nm), KA450PSKR (porous average pore diameter: 230 nm), KA450SLU (porous average pore diameter: 210 nm) (manufactured by Seiko Epson Corporation) ), BP71GAA4 (porous average pore diameter: 220 nm) (manufactured by Brother Industries, Ltd.) and the like.

-Scratch resistance of ink containing silver-
After the ink containing silver is applied to the recording medium and an image is formed, the scratch resistance can be improved by providing a transparent resin layer on the printing layer containing silver.
In addition, a transparent resin layer may be provided on a print layer to which a color ink containing a color material other than silver is further applied after an ink containing silver is applied to the recording medium.

<Laminate layer forming step and laminate layer forming means>
The laminate layer forming step is a step of further forming a laminate layer on the region to which the silver ink is applied after the silver ink applying step, and is performed by a laminate layer forming unit.
The resin of the resin layer on the printed layer (hereinafter sometimes referred to as a laminate layer) preferably has high transparency, and typical examples thereof include polyethylene terephthalate (PET) and polypropylene (PP). Nylon may be used, and a method of coating the surface of the printing layer or the entire printed material by a so-called laminating process is preferable. Moreover, you may coat | cover with transparent overcoat which melt | dissolves and apply | coats water and a solvent.
As the laminate layer forming step, for example, a blade coating method, a gravure coating method, a bar coating method, a roll coating method, a dip coating method, a curtain coating method, a slide coating method, a die coating method, a spray coating method, etc. can be used to form a layer. It is.
Examples of the laminate layer forming means include a bar coater and a pressure roller.
The average thickness of the resin layer formed on the print layer is preferably 5 μm to 300 μm. When the average thickness of the resin layer is less than 5 μm, the scratch resistance and the durability of the coating film are not sufficient, and there is an increased risk that the coating effect is not obtained, such as being easily scratched or the coating film being torn. . On the other hand, if the average thickness of the resin layer exceeds 300 μm, in addition to lowering the high image clarity, the b * value exceeds 4, and yellow or red becomes a strong color.

As a method for coating the laminate, it is preferable to cover the printed portion of the printed matter or the entire printed matter with a resin film and apply heat or press-fit without applying heat. A method of coating the printing surface or the entire printed material by a laminating process is preferable.
Note that, as an alternative to laminating, a method of coating with an overcoat in which a transparent resin is dissolved and applied in water or a solvent may be used.

(Recorded material)
The recorded matter of the present invention has a porous material on a recording medium, silver on the porous material, an average pore diameter of the porous material of more than 200 nm and not more than 400 nm, and an average thickness of the porous material of 5 μm. It is 30 μm or less. In addition, it is preferable to have a plurality of porous droplet marks when observed with a scanning electron microscope from the image forming surface side, and it is also preferable that the recording medium is a non-permeable substrate. Furthermore, you may have pigments other than silver on the said porous.
An image can be formed by an inkjet image forming apparatus and an inkjet image forming method to obtain a recorded matter.

<Droplet trace>
When the porous material is formed by an ink jet method, a plurality of droplet traces due to ink droplets are observed, so that it can be clearly distinguished from the coating layer on the recording medium.
The droplet trace is a trace generated by a droplet ejected from an inkjet head, and may be formed by overlapping a circular one or a circular droplet. In the case of overlapping, droplet traces may be mixed, but since they have rounded ends as shown in FIG. 3, they are clearly distinguished from those that are uniform when using a bar coater or the like.
In addition, the droplet trace is not only when the porous forming material is applied to the recording medium using the inkjet method, but also when the silver ink containing silver and the color ink are applied to the recording medium. Observed.
FIG. 3 shows droplet traces 501 observed when silver ink is applied onto a recording medium using an inkjet head. Color ink and a porous forming material are applied onto a recording medium using an inkjet head. In the same manner, droplet marks as shown in FIG. 3 are also observed.
Examples of the method of observing the droplet trace include a method of observing using a scanning electron microscope (SEM).

<Recording apparatus and recording method>
The following describes the case where black (K), cyan (C), magenta (M), and yellow (Y) are used, but instead of these, or in addition to these, ink containing silver is used. Good.
The ink of the present invention can be suitably used for various recording apparatuses using an ink jet recording method, such as a printer, a facsimile apparatus, a copying apparatus, a printer / fax / copier complex machine, and a three-dimensional modeling apparatus.
In the present invention, the recording apparatus and the recording method are an apparatus capable of ejecting ink, various treatment liquids, and the like to a recording medium, and a method of performing recording using the apparatus. The recording medium means a medium on which ink and various processing liquids can be temporarily attached.
The recording apparatus can include not only a head portion that ejects ink but also means for feeding, transporting, and discharging a recording medium, and other devices called pre-processing devices and post-processing devices. .
The recording apparatus and the recording method may include a heating unit used in the heating step and a drying unit used in the drying step. The heating means and the drying means include, for example, a means for heating and drying the printing surface and the back surface of the recording medium. Although it does not specifically limit as a heating means and a drying means, For example, a warm 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 apparatus and the recording method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, what forms patterns, such as a geometric pattern, etc. includes what forms a three-dimensional image.
Further, the recording apparatus includes both a serial type apparatus that moves the ejection head and a line type apparatus that does not move the ejection head, unless otherwise specified.
Furthermore, this recording apparatus can use not only a desktop type but also a wide recording apparatus capable of printing on an A0 size recording medium, for example, continuous paper wound up in a roll shape as the recording medium. Also included are continuous paper printers.
An example of the recording apparatus will be described with reference to FIGS. FIG. 1 is a perspective view of the apparatus. FIG. 2 is an explanatory perspective view of the main tank. An image forming apparatus 400 as an example of a recording apparatus is a serial type image forming apparatus. A mechanism unit 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink storage portion 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, an aluminum laminate film or the like. It is formed of a packaging member. The ink storage unit 411 is stored 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 on the inner side of 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. Thus, the ink discharge ports 413 of the main tank 410 and the discharge heads 434 for the respective colors communicate with each other via the supply tubes 436 for the respective colors, and ink can be discharged from the discharge heads 434 to the recording medium.

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

  The method of using the ink is not limited to the ink jet recording method, and can be widely used. Besides the ink jet recording method, for example, a blade coating method, a gravure coating method, a bar coating method, a roll coating method, a dip coating method, a curtain coating method, a slide coating method, a die coating method, a spray coating method and the like can be mentioned.

The use of the ink of the present invention is not particularly limited and can be appropriately selected depending on the purpose. For example, it can be applied to printed materials, paints, coating materials, foundations and the like. Furthermore, it can be used not only to form two-dimensional characters and images using ink, but also as a three-dimensional modeling material for forming a three-dimensional stereoscopic image (three-dimensional modeled object).
A known three-dimensional modeling apparatus for modeling a three-dimensional modeled object can be used, and is not particularly limited. be able to. The three-dimensional structure includes a three-dimensional structure obtained by repeatedly applying ink. Further, a molded product obtained by processing a structure provided with ink on a substrate such as a recording medium is also included. The molded product is obtained by subjecting a recorded material and a structure formed in a sheet shape or a film shape to a molding process such as heat stretching and punching. -It is suitably used for applications in which the surface is molded after decoration, such as meters for electronic devices, cameras, etc., and panels for operation units.

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

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

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

(Preparation example 1 of resin dispersion)
<Preparation of polyester urethane resin dispersion 1>
200.4 g of polyester polyol (trade name: PTMG 1,000, manufactured by Mitsubishi Chemical Corporation, average molecular weight: 1,000) in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas introduction tube, and a stirrer , 2-dimethylolpropionic acid 15.7 g, isophorone diisocyanate 48.0 g, methyl ethyl ketone 77.1 g as an organic solvent, and dibutyltin dilaurate (DMTDL, manufactured by Tokyo Chemical Industry Co., Ltd.) 0.06 g as a catalyst. It was. After the reaction was continued for 4 hours, 30.7 g of methyl ethyl ketone was supplied as a diluent solvent, and the reaction was further continued. After the reaction was carried out for a total of 6 hours, 1.4 g of methanol was added, and the reaction was terminated to obtain an organic solvent solution of urethane resin. The carboxyl group which the said urethane resin has was neutralized by adding 48 mass% potassium hydroxide aqueous solution to the organic solvent solution of the said urethane resin. Subsequently, 715.3 g of water was added, and after sufficiently stirring, a polyester urethane resin dispersion 1 containing resin particles having a solid content concentration of 30% by mass was obtained by aging and removing the solvent.

(Preparation example 2 of resin dispersion)
<Preparation of polyester urethane resin dispersion 2>
In the resin dispersion preparation example 1, the solid content was changed in the same manner as in the resin dispersion preparation example 1 except that the DMTDL content was 0.06 g and the total reaction time was changed to 8 hours. A polyester urethane resin dispersion 2 containing resin particles having a concentration of 30% by mass was obtained.

(Preparation example 3 of resin dispersion)
<Preparation of polycarbonate urethane resin dispersion 1>
1,500 g of polycarbonate diol (reaction product of 1,6-hexanediol and dimethyl carbonate (number average molecular weight (Mn): 1,200)) in a reaction vessel into which a stirrer, a reflux condenser, and a thermometer were inserted. 2,2-dimethylolpropionic acid (DMPA) (220 g) and N-methylpyrrolidone (NMP) (1,347 g) were charged in a nitrogen stream and heated to 60 ° C. to dissolve DMPA.
Next, 1,445 g (5.5 mol) of 4,4′-dicyclohexylmethane diisocyanate and 2.6 g of dibutyltin dilaurate (catalyst) were added and heated to 90 ° C. to conduct a urethanization reaction over 5 hours. An isocyanate-terminated urethane prepolymer was obtained. The reaction mixture was cooled to 80 ° C., 149 g of triethylamine was added thereto, and 4,340 g was extracted from the mixture, and mixed with a mixture of 5,400 g of water and 15 g of triethylamine under strong stirring. Added to.
Next, 1,500 g of ice was added, and 626 g of a 35% by mass 2-methyl-1,5-pentanediamine aqueous solution was added to carry out a chain extension reaction. Thus, a polycarbonate urethane resin dispersion 1 having a structure derived from alicyclic diisocyanate was obtained.

(Preparation example 4 of resin dispersion)
<Preparation of polycarbonate urethane resin dispersion 2>
In Preparation Example 3 of Resin Dispersion, the same as Preparation Example 3 of Resin Dispersion, except that the content of dibutyltin dilaurate was changed to 2.6 g and the urethanization reaction time of 5 hours was changed to 4 hours. Thus, a polycarbonate urethane resin dispersion 2 containing polycarbonate urethane resin particles having a solid content concentration of 30% by mass was obtained.

(Resin Dispersion Preparation Example 5)
<Preparation of acrylic resin dispersion>
A reaction vessel equipped with a stirrer, a reflux condenser, a dropping device, and a thermometer was charged with 900 g of ion-exchanged water and 1 g of sodium lauryl sulfate, and the temperature was raised to 70 ° C. while purging with nitrogen under stirring. Maintaining the internal temperature at 70 ° C., adding 2 g of potassium persulfate as a polymerization initiator, dissolving, and previously stirring 450 g of ion exchange water, 3 g of sodium lauryl sulfate, 20 g of acrylamide, 365 g of styrene, 545 g of butyl acrylate, and 10 g of methacrylic acid The emulsion prepared by adding below was continuously dropped into the reaction solution over 6 hours. After completion of the dropwise addition, aging was performed for 3 hours.
After cooling the obtained aqueous particles to room temperature, ion exchange water and an aqueous sodium hydroxide solution were added to adjust the solid content concentration to 30% by mass and pH 8 to obtain an acrylic resin dispersion containing acrylic resin particles.

(Preparation example of silver dispersion)
66.8 g of silver nitrate, a polymer dispersant having a carboxyl group (trade name: Dispersic 190, manufactured by Big Chemie Japan Co., Ltd., solvent: water, 40% by mass of nonvolatile components, acid value: 10 mgKOH / g, amine value: 0 mgKOH / g) 7.2 g and 1.8 g of cholic acid (manufactured by Wako Pure Chemical Industries, Ltd.) were added to 100 g of ion-exchanged water and stirred vigorously to obtain a suspension. To the obtained suspension, 100 g 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 in a water bath at a water temperature of 50 ° C. for 3 hours. Stir to obtain a reaction solution.
The obtained reaction liquid was filtered with a glass filter (trade name: GC-90, manufactured by ADVANTEC, average pore diameter: 0.8 μm) to obtain a silver dispersion containing 20% by mass of silver.
When the obtained silver dispersion was measured by Microtrac UPA, manufactured by Nikkiso Co., Ltd., the number average particle diameter of the primary particles was 50 nm.

(Preparation example 1 of silver ink)
<Preparation of silver ink 1>
After mixing the materials of the following prescription to 100 parts by mass in total and stirring, the mixture was filtered through a polypropylene filter (trade name: syringe filter, manufactured by Sartorius Co., Ltd.) having an average pore size of 0.2 μm, and silver ink 1 Got.
-Formulation of silver ink 1-
Silver dispersion: 50.0 parts by mass 2,4,7,9-tetramethyldecane-4,7-diol (manufactured by Tokyo Chemical Industry Co., Ltd.) 0.5 parts by mass -Propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 18.0 parts by mass-3-ethyl-3-hydroxymethyloxetane (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 8.0 parts by mass-Antiseptic / antifungal agent Proxel LV (manufactured by Avicia Co., Ltd.) 0.1 mass part Polyester urethane resin dispersion 1 5.0 mass parts Ion exchange water Remaining amount

(Preparation Examples 2 to 3 of silver ink)
<Preparation of silver inks 2-3>
Silver inks 2 and 3 were obtained in the same manner as in silver ink preparation example 1 except that the formulation was changed as shown in Table 1 below.

(Silver ink preparation example 4)
<Preparation of silver ink 4>
After mixing the materials of the following prescription to 100 parts by mass in total and stirring, the mixture was filtered through a polypropylene filter (trade name: syringe filter, manufactured by Sartorius Co., Ltd.) having an average pore size of 0.2 μm, and silver ink 4 Got.
-Formulation of silver ink 4-
Silver nano colloid (trade name: H-1, manufactured by Mitsubishi Materials Corporation, silver concentration: 20% by mass) ... 37.5 parts by mass 2,4,7,9-tetramethyldecane-4,7- Diol (manufactured by Tokyo Chemical Industry Co., Ltd.) 0.5 parts by mass 1,2-propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) 27.8 parts by mass 3-ethyl-3-hydroxymethyloxetane (Tokyo Chemical Industry Co., Ltd.) ... 4.0 parts by mass-Antiseptic / antifungal agent Proxel LV (Abyssia)-0.1 parts by mass-Polyester urethane resin dispersion 1 ... 0.1 parts by mass・ Ion-exchanged water

(Preparation Example 1 of Pigment Dispersion)
<Preparation of pigment dispersion 1>
After pre-mixing the materials with the following prescription to 100 parts by mass in total, the mixture is circulated and dispersed for 7 hours in a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: 0.3 mm diameter zirconia ball). Thus, a pigment dispersion 1 was obtained.
-Pigment dispersion 1 formulation-
Pigment (Pigment Blue 15: 3): 15 parts by mass Anionic surfactant (Pionin A-51-B, manufactured by Takemoto Yushi Co., Ltd.): 2 parts by mass

(Preparation Examples 2 to 4 of pigment dispersion)
<Preparation of pigment dispersions 2 to 4>
Pigment dispersions 2 to 4 were obtained in the same manner as in Preparation 1 of pigment dispersion, except that the pigment was replaced with the pigment shown in Table 2 below.

(Pigment Dispersion Preparation Example 5)
<Preparation of pigment dispersion 5>
After pre-mixing the materials of the following prescription to 100 parts by mass in total, the mixture was circulated and dispersed for 7 hours in a disk type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: 0.3 mm diameter zirconia ball). . Subsequently, it was circulated and dispersed for 3 hours in a disk type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: 0.1 mm diameter zirconia ball) to obtain pigment dispersion 5.
-Formulation of pigment dispersion 5-
Pigment Blue 15: 3 ... 15 parts by massAnionic surfactant (Pionin A-51-B, Takemoto Yushi Co., Ltd.) ... 2 parts by massIon-exchanged water ... Remaining amount

(Pigment Dispersion Preparation Example 6)
<Preparation of pigment dispersion 6>
After pre-mixing the materials of the following prescription to 100 parts by mass in total, the mixture is circulated and dispersed for 5 hours in a disk-type bead mill (Shinmaru Enterprises Co., Ltd., KDL type, media: 1.0 mm diameter zirconia ball). Thus, a pigment dispersion 6 was obtained.
-Formulation of Pigment Dispersion 6-
Pigment Blue 15: 3 ... 15 parts by massAnionic surfactant (Pionin A-51-B, Takemoto Yushi Co., Ltd.) ... 2 parts by massIon-exchanged water ... Remaining amount

The following materials were used as pigment types.
-Pigment Blue 15: 3 (Daiichi Seika Kogyo Co., Ltd., “Chromo Fine Blue A-220JC”)
Carbon black (Degussa “FW100”)
・ Titanium dioxide (manufactured by Sakai Chemical Industry Co., Ltd., “GTR-100”)
・ Hollow resin emulsion (manufactured by JSR Corporation, “SX-866 (B)”)

(Color ink production example 1)
<Manufacture of color ink 1>
After mixing the materials of the following prescription to a total of 100 parts by mass and stirring, the average pore size was filtered through a 0.2 μm polypropylene filter (trade name: syringe filter, manufactured by Sartorius Co., Ltd.), Produced.
<Ink prescription>
-Pigment dispersion 1 ... 20 parts by mass-Polyester urethane resin dispersion 1-10 parts by mass-Silicone surfactant KF-351A (manufactured by Shin-Etsu Silicone) ... 1 part by mass-2, 4 , 7,9-Tetramethyldecane-4,7-diol (manufactured by Tokyo Chemical Industry Co., Ltd.) 0.5 parts by mass 1,2-propanediol (bp 188 ° C.) 25 parts by mass 3- Ethyl-3-hydroxymethyloxetane (bp 240 ° C., manufactured by Tokyo Chemical Industry Co., Ltd.) 15 parts by mass Antiseptic / antifungal agent Proxel LV (Avicia) 0.1 parts by mass Ion exchange water ·Remaining amount

(Color ink production examples 2 to 6)
<Manufacture of color inks 2-6>
In color ink preparation example 1, color inks 2 to 6 were obtained in the same manner as color ink preparation example 1 except that the formulation was changed as shown in Table 3 below.

(Production Example 1 of recording medium having alumina-based porous material)
<Preparation of recording medium M11 having alumina-based porous material>
A liquid was prepared by adding 1% by mass of a surfactant (FS34, manufactured by DuPont) to alumina clear sol A2 (manufactured by Kawaken Fine Chemical Co., Ltd.). This solution is applied to a vinyl chloride resin sheet (Avery 3000, manufactured by Avery Dennison Japan Co., Ltd.) with a wire bar coat so that the average thickness of the porous film after drying is 4 μm, and the recording has an alumina-based porous material. Medium M11 was obtained. Then, when the porous average hole diameter was confirmed by surface observation with SEM, it was 400 nm.

(Production Example 2 of recording medium having alumina-based porous material)
<Preparation of recording medium M12 having alumina-based porous material>
In the production example 1 of a recording medium having an alumina-based porous material, the same procedure as in Production example 1 of a recording medium having an alumina-based porous material was performed except that the average porous thickness after drying was 30 μm. A recording medium M12 having an alumina-based porous material was obtained. Then, when the porous average hole diameter was confirmed by surface observation with SEM, it was 400 nm.

(Production Example 1 of recording medium having silica-based porous material)
<Preparation of recording medium M13 having silica-based porous material>
1% by mass of a surfactant (FS34, manufactured by DuPont) was added to Snowtech UP (manufactured by Nissan Chemical Industries, Ltd.) to prepare a mixed solution. This liquid was applied to OK top coat paper (manufactured by Oji Paper Co., Ltd.) by wire bar coating so that the average thickness of the porous film after drying was 6 μm, and a recording medium M13 having silica-based porous material was obtained. . Then, when the porous average hole diameter was confirmed by surface observation with SEM, it was 201 nm.

(Production Example 2 of recording medium having silica-based porous material)
<Preparation of recording medium M14 having silica-based porous material>
In Preparation Example 1 of a recording medium having a silica-based porous material, the same procedure as in Preparation Example 1 of a recording medium having a silica-based porous material was performed except that the average porous thickness after drying was 31 μm. A recording medium M14 having silica-based porosity was obtained. Then, when the porous average hole diameter was confirmed by surface observation with SEM, it was 201 nm.

  Table 4 below shows the porous average pore diameter and the average porous thickness of the recording medium. M1 to 10 and M15 are commercially available products, and M11 to M14 are manufactured in the above manufacturing example.

In Table 4, M5 to M9 do not have a receiving layer.

(Production example of alumina-based porous material)
<Production Example 1 of Porous Forming Material>
After mixing and stirring the materials of the following prescription to 100 parts by mass in total, the average pore size is filtered through a 5 μm polypropylene filter (trade name: syringe filter, manufactured by Sartorius Co., Ltd.) to form a porous forming material 1 Was made.
<Prescription>
Alumina clear sol A2 (manufactured by Kawaken Fine Chemical Co., Ltd.) 70 parts by mass Surfactant Emulgen LS-106 (manufactured by Kao Corporation) 0.8 parts by mass 1,3-butanediol (Tokyo) (Made by Kasei Kogyo Co., Ltd.) ... 12 parts by mass-Polyester urethane resin dispersion 1 ... 2.5 parts by mass-3-ethyl-3-hydroxymethyloxetane (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 5 parts by mass Part ・ Preservative / antifungal agent Proxel LV (manufactured by Avicia) ・ ・ ・ 0.1 part ・ Ion-exchanged water

<Production Examples 2 and 3 of porous forming material>
Porous forming materials 2 and 3 were obtained in the same manner as Porous forming material manufacturing example 1 except that the formulation was changed as shown in Table 5 below. .

In addition, the following materials were used as the porous main component and the surfactant in the porous forming material 2 and the porous forming material 3.
・ Alumina clear sol 5S (manufactured by Kawaken Fine Chemical Co., Ltd.)
・ Alumina clear sol F1000 (manufactured by Kawaken Fine Chemical Co., Ltd.)
・ FS-3434 (DuPont)

(Example of production of silica-based porous material)
<Production Example 4 of Porous Forming Material>
After mixing and stirring the materials of the following prescription to 100 parts by mass in total, the average pore size was filtered through a polypropylene filter (trade name: syringe filter, manufactured by Sartorius Co., Ltd.), and the porous forming material 4 Was made.
<Prescription>
・ Snowtech S (Nissan Chemical Industry Co., Ltd.): 60 parts by mass Surfactant FS-34 (DuPont): 1 part by mass ・ 1,3-butanediol (Tokyo Chemical Industry Co., Ltd.) ) ... 13 parts by mass-Polyester urethane resin dispersion 2 ... 6 parts by mass-3-ethyl-3-hydroxymethyloxetane (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 5 parts by mass-Antiseptic / antifungal agent Proxel LV (manufactured by Avicia) ... 0.1 parts by mass

<Production Examples 5 and 6 of porous forming material>
Porous forming materials 5 and 6 were obtained in the same manner as in Porous forming material production example 4, except that the formulation was changed as shown in Table 6 below. .

In addition, the following materials were used as the porous main component in the porous forming material 5 and the porous forming material 6.
・ Snow Tech UP (Nissan Chemical Industry Co., Ltd.)
・ Cataloid SI-30 (manufactured by JGC Catalysts & Chemicals Co., Ltd.)

(Examples 1-42)
Using an inkjet printer (Ricoh Co., Ltd., IPSiO GXe5500), a solid image of the porous forming material shown in Table 7 was printed at 25 ° C. on the recording medium shown in Table 7 and dried to form a porous material. did.
Next, using the ink-jet printer (IPSiO GXe5500, manufactured by Ricoh Co., Ltd.) on the formed porous material, the silver ink and color ink shown in Table 8 were printed by the printing (order and color mixture) method shown in Table 8. The image was printed at 25 ° C. and dried.
Thereafter, when forming a laminate layer, the printed layer was laminated with the material types and average thicknesses shown in Table 8 to obtain a recorded matter having a laminate (resin) layer on the printed layer.

(Comparative Examples 1-17)
The recorded matter of Comparative Examples 1-17 was obtained like Example 1-42 except having changed into the conditions shown in Table 9 and Table 10 using the inkjet printer (the Ricoh Co., Ltd. make, IPSiO GXe5500). .

  Note that the average pore diameter, average thickness, and droplet trace of the recorded matter are as follows for a 10 μm square porous region in which no silver ink or color ink is attached in the SEM image of the recorded matter surface: Was measured as follows. The results are shown in Table 7 and Table 9.

<Porous average pore diameter>
For the average pore diameter of the porous material, the lengths of the two longest and shortest diagonal lines were obtained for all the voids (porous pores) observed in the 10 μm square area in the SEM image of the recorded material surface layer. It calculated using the average value (porous pore diameter) of the diagonal line of a book. In calculating the average value, the pore diameter of the porous material of 100 nm or less was not considered in the calculation.

<Porosity average thickness>
The average porous thickness was calculated from the SEM image of the cross section of the recorded material. Find the average value of the porous thickness at three points: the midpoint of the cross section of the recorded material, the midpoint between one end of the cross section and the midpoint, and the midpoint between the other end of the cross section and the midpoint. It was. In addition, about the part whose average pore diameter of the said porous exceeds 200 nm and is not 400 nm or less, it did not use for calculation of the porous average thickness.

<Evaluation of porous droplet marks>
As shown in FIG. 3, the surface of each recorded material obtained is observed with a scanning electron microscope (SEM) image of the surface, and whether or not there are a plurality (two or more) of porous substantially circular droplet marks is present. Determined.

Next, various properties of the obtained recorded material were evaluated as follows. The results are summarized in Table 11 and Table 12.
In addition, each evaluation was measured after drying a recorded matter, and when performing a lamination process, evaluation was performed after the lamination process.

<Abrasion resistance evaluation>
Each recorded matter obtained was set on a Gakushin type wear fastness tester AB-301 (trade name, manufactured by Tester Sangyo Co., Ltd.), and a friction piece (load) ; 300 g), and the deterioration was visually observed, and scratch resistance was evaluated according to the following criteria. In addition, B or more is a level which does not have a problem practically, Preferably it is A or more.
〔Evaluation criteria〕
S: The number of scratches is less than 5 and the background is not visible A: The number of scratches is 5 or more and less than 10 and the background is not visible B: The number of scratches is 10 or more and the background is not exposed Less than 5% C: The number of scratches is 10 or more, and the exposure of the base is 5% or more

<Glossiness evaluation>
The 20 ° glossiness of each of the obtained recorded materials was measured with a gloss meter (manufactured by BYK Gardener Co., Ltd., Micro Trigloss) and evaluated according to the following criteria. In addition, B or more is a level which does not have a problem practically, Preferably it is A or more.
〔Evaluation criteria〕
S: 20 ° gloss is 800 or more A: 20 ° gloss is 500 or more and less than 800 B: 20 ° gloss is 250 or more and less than 500 C: 20 ° gloss is less than 250

<Image clarity evaluation>
Using the Suga test machine ICM-1 type, the image clarity value C of each recorded matter obtained was measured for image clarity with an optical comb width of 2.0 mm by the image clarity measurement method defined in JIS-H8686. Evaluation was made according to the following criteria. In addition, B or more is a level which does not have a problem practically, Preferably it is A or more.
〔Evaluation criteria〕
S: Image clarity value C is 50 or more A: Image clarity value C is 30 or more and less than 50 B: Image clarity value C is 5 or more and less than 30 C: Image clarity value C is less than 5

As an aspect of this invention, it is as follows, for example.
<1> A porous material on which a porous material is formed on a recording medium by using an inkjet head to form a porous material having an average pore diameter of more than 200 nm and not more than 400 nm and an average thickness of not less than 5 μm and not more than 30 μm. An image forming method comprising: a forming step; and a silver ink applying step of applying a silver ink containing silver on the porous body.
<2> The image forming method according to <1>, wherein the porous forming material includes at least one of alumina and silica.
<3> The image according to <1> or <2>, wherein, in the porous formation step, the average pore diameter is 250 nm to 360 nm and the average thickness is 20 μm to 30 μm. It is a forming method.
<4> The image forming method according to any one of <1> to <3>, further including a color ink applying step of applying a color ink containing a color material to the recording medium.
<5> The image forming method according to <4>, wherein the silver ink and the color ink contain a resin.
<6> The image forming method according to <4> or <5>, wherein the color ink applying step is performed after the silver ink applying step.
<7> The image forming method according to any one of <1> to <6>, wherein the recording medium is a non-permeable substrate.
<8> The image forming method according to <7>, wherein the non-permeable substrate is a plastic film.
<9> The image formation according to any one of <1> to <8>, further including a laminate layer forming step of forming a laminate layer on the region applied with the silver ink after the silver ink applying step. Is the method.
<10> The recording medium has porosity,
Having silver on the porous;
The porous average pore diameter is more than 200 nm and not more than 400 nm,
An average thickness of the porous material is 5 μm or more and 30 μm or less.
<11> The recorded matter according to <10>, having a plurality of porous droplet marks when observed with a scanning electron microscope from the image forming surface side.
<12> The recorded matter according to <10> or <11>, wherein the recording medium is a non-permeable base material.
<13> The recorded matter according to <12>, wherein the non-permeable substrate is a plastic film.
<14> A porous forming step of providing a porous forming material on a non-permeable substrate, forming a porous material having an average pore diameter of more than 200 nm and not more than 400 nm, and an average thickness of not less than 5 μm and not more than 30 μm. When,
A silver ink applying step of applying a silver ink containing silver on the porous;
An image forming method comprising:
<15> The image forming method according to <14>, wherein the non-permeable substrate is a plastic film.
<16> Porous forming means for providing a porous forming material on the recording medium, forming a porous material having an average pore diameter of more than 200 nm and not more than 400 nm, and an average thickness of not less than 5 μm and not more than 30 μm;
Silver ink application means for applying a silver ink containing silver on the porous body,
An image forming apparatus comprising:
<17> The image forming apparatus according to <16>, wherein the recording medium is a non-permeable base material.
<18> The image forming apparatus according to <17>, wherein the non-permeable substrate is a plastic film.
<19> The image forming apparatus according to any one of <16> to <18>, wherein the porous forming unit and the silver ink applying unit are inkjet heads.

  The image forming method according to any one of <1> to <9> and <14> to <15>, the recorded matter according to any of <10> to <13>, and <16> to <15> The image forming apparatus according to any one of 19> can solve the above-described problems and achieve the object of the present invention.

Japanese Patent No. 4165860 Japanese Patent Laid-Open No. 2006-135600 JP 2012-161959 A

100 Porous void 101 One of the diagonals of the porous pore (a)
102 One of the diagonals of the porous pore (b)
400 Image forming apparatus 401 Exterior of image forming apparatus 401c Cover of apparatus main body 404 Cartridge holder 410 Main tank 410k, 410c, 410m, 410y For each color of black (K), cyan (C), magenta (M), yellow (Y) Main tank 411 ink container 413 ink outlet 414 container case 420 mechanism 434 discharge head 436 supply tube 501 droplet trace

Claims (19)

A porous forming step of providing a porous forming material on a recording medium using an inkjet head, forming a porous material having an average pore diameter of more than 200 nm and not more than 400 nm, and an average thickness of not less than 5 μm and not more than 30 μm; ,
A silver ink applying step of applying a silver ink containing silver on the porous;
An image forming method comprising:   The image forming method according to claim 1, wherein the porous forming material contains at least one of alumina and silica. In the porous forming step,
The image forming method according to claim 1, wherein the porous material has an average pore diameter of 250 nm to 360 nm and an average thickness of 20 μm to 30 μm.   The image forming method according to claim 1, further comprising a color ink applying step of applying a color ink containing a color material to the recording medium.   The image forming method according to claim 4, wherein the silver ink and the color ink contain a resin.   The image forming method according to claim 4, wherein the color ink applying step is performed after the silver ink applying step.   The image forming method according to claim 1, wherein the recording medium is a non-permeable substrate.   The image forming method according to claim 7, wherein the non-permeable substrate is a plastic film.   The image forming method according to any one of claims 1 to 8, further comprising a laminate layer forming step of forming a laminate layer on the region to which the silver ink has been applied after the silver ink applying step. Having porosity on the recording medium,
Having silver on the porous;
The porous average pore diameter is more than 200 nm and not more than 400 nm,
The recorded matter, wherein the porous average thickness is 5 μm or more and 30 μm or less.   The recorded matter according to claim 10, which has a plurality of porous droplet marks when observed with a scanning electron microscope from the image forming surface side.   The recorded matter according to claim 10 or 11, wherein the recording medium is a non-permeable substrate.   The recorded matter according to claim 12, wherein the non-permeable substrate is a plastic film. A porous forming step of providing a porous forming material on the non-permeable substrate, forming a porous material having an average pore diameter of more than 200 nm and not more than 400 nm, and an average thickness of 5 μm or more and 30 μm or less;
A silver ink applying step of applying a silver ink containing silver on the porous;
An image forming method comprising:   The image forming method according to claim 14, wherein the non-permeable substrate is a plastic film. A porous forming means for providing a porous forming material on a recording medium, forming a porous material having an average pore diameter of more than 200 nm and not more than 400 nm, and an average thickness of not less than 5 μm and not more than 30 μm;
Silver ink application means for applying a silver ink containing silver on the porous body,
An image forming apparatus comprising:   The image forming apparatus according to claim 16, wherein the recording medium is a non-permeable base material.   The image forming apparatus according to claim 17, wherein the non-permeable substrate is a plastic film. The image forming apparatus according to claim 16, wherein the porous forming unit and the silver ink applying unit are ink jet heads.