JP7040091B2 - Ink set, printing method, and printing equipment - Google Patents

Description

The present invention relates to an ink set, a printing method, and a printing apparatus.

A method (DTG: Direct to Garment) of printing directly on textile products such as T-shirts with ink or the like is known. Such a printing method has the characteristics that it is possible to obtain a printed matter having high small lot compatibility and high designability, and has a small environmental load.

When printing is performed by directly applying ink to a recording medium composed of fibers by an inkjet method, generally, the recording medium after printing is heat-treated by heating at 100 ° C. or higher to fix the coloring material in the ink. This suppresses ink bleeding. However, when such a heat treatment is performed on a recording medium containing synthetic fibers such as polyurethane and nylon, the fabric may be denatured and the texture may be impaired.

Further, as a method of printing without performing a heat treatment for heating a recording medium after printing, a method using dye ink is known. However, the image density of the dye ink may decrease depending on the combination of the type of dye used and the fiber material constituting the recording medium.

Patent Document 1 contains a first liquid containing at least a coloring material, a polymer substance, a water-soluble solvent, and water, and at least a coagulant, a water-soluble solvent, and water. Disclosed are ink sets for inkjets that have two liquids and further contain a plasticant in at least one of the first liquid and the second liquid. Further, it is disclosed that these ink sets form a pigment aggregate containing a coloring material, a polymer substance and a plasticizer by mixing two kinds of liquids, and further form a film. However, the recording medium composed of fibers has high flexibility and the film formation is easily broken by the movement of the fibers, and if the fixing material on the fiber surface is a pigment aggregate, the followability to the recording medium is inferior and the friction fastness May be inferior to.

An object of the present invention is to provide an ink set which can suppress bleeding, has excellent image density, and has excellent friction fastness.

The invention according to claim 1 includes a water-based ink containing water, an organic solvent, a pigment, and resin particles, and a non-water-based ink containing a plasticizer, wherein the plasticizer is an ester compound and described above. The ester compound is an ink set which is at least one selected from the group consisting of a dicarboxylic acid ester, a tricarboxylic acid ester, and a phosphoric acid ester .

The ink set of the present invention can suppress bleeding, has excellent image density, and has excellent friction fastness.

FIG. 1 is a perspective explanatory view showing an example of a printing apparatus. FIG. 2 is a perspective explanatory view showing an example of the main tank.

Hereinafter, embodiments of the present invention will be described.

[Ink set]
The ink set of the present invention has a water-based ink and a non-water-based ink. The water-based ink and the non-water-based ink may be one type or a plurality of types, respectively.

<< Water-based ink >>
The water-based ink contains water, an organic solvent, a pigment, and resin particles, and if necessary, contains a surfactant and the like.

<Organic solvent>
The organic solvent used in the present invention is not particularly limited, and a water-soluble organic solvent can be used. Examples thereof include ethers such as polyhydric alcohols, polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines and sulfur-containing compounds.
Specific examples of polyhydric alcohols 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, Glycolin, 1,2,6-hexanetriol, 2-ethyl-1,3-hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl- Examples thereof include 1,3-pentanediol and petriol.
Examples of the polyhydric alcohol alkyl ethers include 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 the polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.
Examples of the nitrogen-containing heterocyclic compound include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, ε-caprolactam, and γ-butyrolactone. Can be mentioned.
Examples of the amides include formamide, N-methylformamide, N, N-dimethylformamide, 3-methoxy-N, N-dimethylpropionamide, 3-butoxy-N, N-dimethylpropionamide and the like.
Examples of amines include monoethanolamine, diethanolamine, triethylamine and the like.
Examples of sulfur-containing compounds include dimethyl sulfoxide, sulfolane, and thiodiethanol.
Examples of other organic solvents include propylene carbonate and ethylene carbonate.
It is preferable to use an organic solvent having a boiling point of 250 ° C. or lower because it not only functions as a wetting agent but also has good drying properties.

Among organic solvents, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, and 2,3-butane from the viewpoint of preventing particle aggregation in water-based inks. Diol, 2-methyl-2,4-pentanediol and dipropylene glycol monomethyl ether are preferred. In addition, 1,2-propanediol, 1,2-butanediol, and 2,3-butanediol having a boiling point of less than 200 ° C. from the viewpoint of high scratch resistance, solvent resistance, and promotion of resin film formation. Is preferable.

The content of the organic solvent is not particularly limited, and is preferably 20% by mass or more and 70% by mass or less, more preferably 30% by mass or more and 60% by mass or less, based on the total amount of the water-based ink. When the content is 20% by mass or more and 70% by mass or less, excellent drying property and good discharge stability can be obtained.

<Water>
The water is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include ion-exchanged water, ultra-filtered water, reverse osmosis water, pure water such as distilled water, and ultrapure water. These may be used alone or in combination of two or more. The water content is preferably 15% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 40% by mass or less, based on the total amount of the water-based ink. When the content is 15% by mass or more, high viscosity can be prevented and discharge stability can be improved.

<Pigment>
As the pigment, an inorganic pigment or an organic pigment can be used. These may be used alone or in combination of two or more. Further, a mixed crystal may be used as the pigment.
As the pigment, for example, a black pigment, a yellow pigment, a magenta pigment, a cyan pigment, a white pigment, a green pigment, an orange pigment, a glossy color pigment such as gold or silver, a metallic pigment, or the like can be used.
As inorganic pigments, carbon black produced by known methods such as contact method, furnace method, thermal method, in addition to titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, and chrome yellow. Can be used.
Examples of organic pigments include azo pigments and polycyclic pigments (for example, phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.). , Dye chelate (for example, basic dye type chelate, acid dye type chelate, etc.), nitro pigment, nitroso pigment, aniline black and the like can be used. Among these pigments, those having a good affinity with a solvent are preferably used. In addition, resin hollow particles and inorganic hollow particles can also be used.
As a specific example of the pigment, for black, carbon black (CI pigment black 7) such as furnace black, lamp black, acetylene black, channel black, or copper, iron (CI pigment black 11) , Metals such as titanium oxide, and organic pigments such as aniline black (CI pigment black 1).
Further, for color, C.I. I. Pigment Yellow 1, 3, 12, 13, 14, 17, 24, 34, 35, 37, 42 (yellow iron oxide), 53, 55, 74, 81, 83, 95, 97, 98, 100, 101, 104 , 108, 109, 110, 117, 120, 138, 150, 153, 155, 180, 185, 213, C.I. I. Pigment Orange 5, 13, 16, 17, 36, 43, 51, C.I. I. Pigment Red 1, 2, 3, 5, 17, 22, 23, 31, 38, 48: 2, 48: 2 (Permanent Red 2B (Ca)), 48: 3, 48: 4, 49: 1, 52: 2, 53: 1, 57: 1 (Brilliant Calcium 6B), 60: 1, 63: 1, 63: 2, 64: 1, 81, 83, 88, 101 (Bengara), 104, 105, 106, 108 ( Cadmium Red), 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 184, 185, 190, 193, 202, 207, 208, 209, 213, 219, 224, 254, 264, C.I. I. Pigment Violet 1 (Rhodamine Lake), 3, 5: 1, 16, 19, 23, 38, C.I. I. Pigment Blue 1, 2, 15 (phthalocyanine blue), 15: 1, 15: 2, 15: 3, 15: 4 (phthalocyanine blue), 16, 17: 1, 56, 60, 63, C.I. I. Pigment Greens 1, 4, 7, 8, 10, 17, 18, 36, etc.

The content of the pigment is preferably 0.1% by mass or more and 10% by mass or less, and preferably 1% by mass or more and 10% by mass or less. When the content is 0.1% by mass or more and 10% by mass or less, the image density, fixability, and ejection stability can be improved.

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

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

<Resin particles>
The water-based ink of the present application contains resin particles. Since the resin particles function as a binder and form an ink film as the water evaporates, the pigment can be fixed on the recording medium even at room temperature, which does not require heating.
As the resin particles, one type may be used alone, or two or more types of resin particles may be used in combination. The resin particles are not particularly limited, but for example, polyester resin particles; polyurethane resin particles; epoxy resin particles; polyamide resin particles; polyether resin particles; acrylic resin particles; acrylic-silicone resin particles; condensation of fluororesins and the like. Synthetic resin particles; polyolefin resin particles, polystyrene resin particles, polyvinyl alcohol resin particles, polyvinyl ester resin particles, polyacrylic acid resin particles, unsaturated carboxylic acid resin and other additive synthetic resin particles; celluloses, Examples thereof include natural polymers such as rosins and natural rubber. As the resin particles, those synthesized as appropriate may be used, or commercially available products may be used.

The resin particles are not particularly limited, but are preferably in the state of an emulsion using water as a dispersion medium. This makes it possible to easily obtain a water-based ink by mixing it with a material such as a pigment or an organic solvent.
When dispersing the resin particles in the aqueous medium, a forced emulsification type using a dispersant can be used, but the molecular structure can prevent the strength from being lowered due to the remaining dispersant in the coating film. So-called self-emulsifying resin particles having an anionic group are suitable.
The acid value of the anionic group of the self-emulsifying resin particles is preferably 5 mgKOH / g or more and 100 mgKOH / g or less, and 5 mgKOH / mg or more and 50 mgKOH / mg from the viewpoint of water dispersibility, abrasion resistance, and chemical resistance. The following are more preferable.
Examples of the anionic group include a carboxyl group, a carboxylate group, a sulfonic acid group, a sulfonate group and the like. Among these, a carboxylate group or a sulfonate group partially or wholly neutralized with a basic compound or the like is preferable from the viewpoint of maintaining good aqueous dispersion stability. In order to introduce an anionic group into the resin, a monomer having an anionic group may be used.
Examples of the method for producing an aqueous dispersion of resin particles having an anionic group include a method of adding a basic compound that can be used for neutralizing the anionic group to the aqueous dispersion. Examples of the basic compound include organic amines such as ammonia, triethylamine, pyridine and morpholine; alkanolamines such as monoethanolamine; and metal base compounds containing Na, K, Li, Ca and the like. These may be used alone or in combination of two or more.
As a method for producing an aqueous dispersion using forced emulsified resin particles, for example, a surfactant such as a nonionic surfactant or an anionic surfactant can be used. These may be used alone or in combination of two or more. Among these, a nonionic surfactant is preferable from the viewpoint of water resistance.

The volume average particle size of the resin particles is particularly preferably 10 nm or more and 1,000 nm or less, more preferably 10 nm or more and 200 nm or less, and particularly preferably 10 nm or more and 100 nm or less, considering that it is used in an inkjet printing apparatus. By using resin particles having a volume average particle diameter of 10 nm or more and 1,000 nm or less, the contact points between the organic solvent and the surface of the resin particles are increased, the film-forming property of the resin particles is improved, and a continuous coating of tough resin is formed. Since it is formed, high image hardness can be obtained. The volume average particle size can be measured using, for example, a particle size analyzer (Microtrac MODEL UPA9340, manufactured by Nikkiso Co., Ltd.).
The content of the resin is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 1% by mass or more and 30% by mass or less, and 5% by mass or more and 20% by mass or less, based on the total amount of the water-based ink. Is more preferable.

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

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

（但し、一般式（Ｓ－１）式中、ｍ、ｎ、ａ、及びｂは、それぞれ独立に、整数を表わし、Ｒは、アルキレン基を表し、Ｒ’は、アルキル基を表す。）
上記のポリエーテル変性シリコーン系界面活性剤としては、市販品を用いることができ、例えば、ＫＦ－６１８、ＫＦ－６４２、ＫＦ－６４３（信越化学工業株式会社）、ＥＭＡＬＥＸ－ＳＳ－５６０２、ＳＳ－１９０６ＥＸ（日本エマルジョン株式会社）、ＦＺ－２１０５、ＦＺ－２１１８、ＦＺ－２１５４、ＦＺ－２１６１、ＦＺ－２１６２、ＦＺ－２１６３、ＦＺ－２１６４（東レ・ダウコーニング・シリコーン株式会社）、ＢＹＫ－３３、ＢＹＫ－３８７（ビックケミー株式会社）、ＴＳＦ４４４０、ＴＳＦ４４５２、ＴＳＦ４４５３（東芝シリコン株式会社）などが挙げられる。 The silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, side-chain modified polydimethylsiloxane, double-ended modified polydimethylsiloxane, one-ended modified polydimethylsiloxane, side chain. Examples thereof include both-terminal modified polydimethylsiloxane, and a polyether-modified silicone-based surfactant having a polyoxyethylene group and a polyoxyethylene polyoxypropylene group as modifying groups is particularly preferable because it exhibits good properties as an aqueous surfactant. ..
As such a surfactant, an appropriately synthesized one may be used, or a commercially available product may be used. As commercially available products, for example, they can be obtained from Big Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Toray Dow Corning Silicone Co., Ltd., Nippon Emulsion Co., Ltd., Kyoeisha Chemical Co., Ltd. and the like.
The above-mentioned polyether-modified silicone-based surfactant is not particularly limited and may be appropriately selected depending on the intended purpose. For example, a polyalkylene oxide structure represented by the general formula (S-1) is dimethylpoly. Examples thereof include those introduced into the Si part side chain of siloxane.

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

上記一般式（Ｆ－１）で表される化合物において、水溶性を付与するためにｍは０～１０の整数が好ましく、ｎは０～４０の整数が好ましい。

上記一般式（Ｆ－２）で表される化合物において、ＹはＨ、又はＣｍＦ_２ｍ＋１でｍは１～６の整数、又はＣＨ_２ＣＨ（ＯＨ）ＣＨ_２－ＣｍＦ_２ｍ＋１でｍは４～６の整数、又はＣｐＨ_２ｐ＋１でｐは１～１９の整数である。ｎは１～６の整数である。ａは４～１４の整数である。
上記のフッ素系界面活性剤としては市販品を使用してもよい。この市販品としては、例えば、サーフロンＳ－１１１、Ｓ－１１２、Ｓ－１１３、Ｓ－１２１、Ｓ－１３１、Ｓ－１３２、Ｓ－１４１、Ｓ－１４５（いずれも、旭硝子株式会社製）；フルラードＦＣ－９３、ＦＣ－９５、ＦＣ－９８、ＦＣ－１２９、ＦＣ－１３５、ＦＣ－１７０Ｃ、ＦＣ－４３０、ＦＣ－４３１（いずれも、住友スリーエム株式会社製）；メガファックＦ－４７０、Ｆ－１４０５、Ｆ－４７４（いずれも、大日本インキ化学工業株式会社製）；ゾニール（Ｚｏｎｙｌ）ＴＢＳ、ＦＳＰ、ＦＳＡ、ＦＳＮ－１００、ＦＳＮ、ＦＳＯ－１００、ＦＳＯ、ＦＳ－３００、ＵＲ、キャプストーンＦＳ－３０、ＦＳ－３１、ＦＳ－３１００、ＦＳ－３４、ＦＳ－３５（いずれも、Ｃｈｅｍｏｕｒｓ社製）；ＦＴ－１１０、ＦＴ－２５０、ＦＴ－２５１、ＦＴ－４００Ｓ、ＦＴ－１５０、ＦＴ－４００ＳＷ（いずれも、株式会社ネオス社製）、ポリフォックスＰＦ－１３６Ａ，ＰＦ－１５６Ａ、ＰＦ－１５１Ｎ、ＰＦ－１５４、ＰＦ－１５９（オムノバ社製）、ユニダインＤＳＮ－４０３Ｎ（ダイキン工業株式会社製）などが挙げられ、これらの中でも、良好な印字品質、特に発色性、紙に対する浸透性、濡れ性、均染性が著しく向上する点から、Ｃｈｅｍｏｕｒｓ社製のＦＳ－３１００、ＦＳ－３４、ＦＳ－３００、株式会社ネオス製のＦＴ－１１０、ＦＴ－２５０、ＦＴ－２５１、ＦＴ－４００Ｓ、ＦＴ－１５０、ＦＴ－４００ＳＷ、オムノバ社製のポリフォックスＰＦ－１５１Ｎ及びダイキン工業株式会社製のユニダインＤＳＮ－４０３Ｎが特に好ましい。 As the fluorine-based surfactant, a compound having 2 to 16 carbon atoms substituted with fluorine is preferable, and a compound having 4 to 16 carbon atoms substituted with fluorine is more preferable.
Examples of the fluorosurfactant include a perfluoroalkyl phosphate ester compound, a perfluoroalkylethylene oxide adduct, and a polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain.
Among these, the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain is preferable because it has less foaming property, and is particularly a fluorine-based compound represented by the general formula (F-1) and the general formula (F-2). Surfactants are preferred.

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.

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

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

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

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

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

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

<Viscosity>
The viscosity of the water-based ink is preferably 2 mPa · s or more, more preferably 3 mPa · s or more and 20 mPa · s or less at 25 ° C. from the viewpoint of image quality such as character quality when printed on a recording medium. When the viscosity is 2 mPa · s or more, the discharge stability can be improved.

<Manufacturing method of water-based ink>
As a method for producing the water-based ink, for example, water, an organic solvent, resin particles, and if necessary, a surfactant and other components may be dispersed or dissolved in an aqueous medium, and appropriately stirred and mixed to produce the water-based ink. can. As the stirring and mixing, for example, a sand mill, a homogenizer, a ball mill, a paint shaker, an ultrasonic disperser, a stirrer using a normal stirring blade, a magnetic stirrer, a high-speed disperser and the like can be used.

<< Non-water-based ink >>
The non-aqueous ink contains a plasticizer and, if necessary, other components such as a viscosity modifier. The non-aqueous ink means an ink composition containing substantially no water in the ink composition, and the content of water contained in the ink composition is 1.0% or less with respect to the total amount of the ink composition. It is preferably present, and more preferably 0.5% or less.

<Plasticizer>
The plasticizer is a compound having an effect of lowering the glass transition temperature (Tg) of the resin when added to the resin. In the present application, the glass transition temperature (Tg) of the resin in the ink film derived from the resin particles in the ink is obtained by containing the plasticizer in the non-aqueous ink in the ink film formed by the water-based ink containing the resin particles. To reduce. As a result, an ink film containing a plasticizer is formed, and the ink film softens due to the plasticizing effect of the plasticizer, which improves the followability of the ink film to the movement of the recording medium and improves the frictional fastness of the printed image portion. improves. As in the present application, by incorporating a plasticizer in a non-water-based ink instead of a water-based ink and bringing it into contact with the water-based ink, excessive mixing between the two inks can be suppressed, and accordingly, the water-based ink containing a pigment is contained. Ink bleeding can be suppressed.
Further, the plasticizer preferably has a function of lowering the Tg of the resin constituting the resin particles contained in the water-based ink to room temperature (25 ° C.) or lower. Specifically, in the water-based ink and the non-water-based ink applied to the same place on the recording medium, the content of the resin particles contained in the water-based ink and the content of the plasticizer contained in the non-water-based ink. When the mass ratio is P, the Tg of the mixture of the resin constituting the resin particles contained in the water-based ink and the plasticizer contained in the non-aqueous ink at the mass ratio P is room temperature (25 ° C.) or less. Is preferable. Examples of the method of lowering the Tg of the resin to room temperature (25 ° C.) or lower by using a plasticizer include a method of adjusting the content of the plasticizer in the non-aqueous ink, a method of selecting the type of the plasticizer, and the like. However, it is not particularly limited.
Examples of the plasticizer include compounds such as esters, amides, ethers, alcohols, lactones, and polyethylene oxys. Among these, it is preferable to use an ester compound. As the plasticizer, one kind may be used, or two or more kinds of plasticizers may be used.

-Ester compound-
As the ester compound, any of monocarboxylic acid ester, dicarboxylic acid ester, tricarboxylic acid ester, phosphoric acid ester and the like may be used, but dicarboxylic acid ester, tricarboxylic acid ester and phosphoric acid ester are preferable. The plasticizer penetrates between the arranged resin molecules of the ink film formed by applying the water-based ink to the recording medium, increases the intermolecular distance between the resin molecules, and improves the flexibility of the ink film. It is thought that it is exerting the effect of making it. Therefore, among the ester compounds, those having a linear and long structure and a spatially bulky structure such as a dicarboxylic acid ester, a tricarboxylic acid ester, and a phosphoric acid ester are preferable. However, the plasticizer having such a structure has low water solubility, and it is difficult to contain it in a large amount in a water-soluble medium. Therefore, even if the plasticizer is contained in a water-based medium instead of the non-water-based ink, the resin cannot be sufficiently plasticized, and as a result, it may be difficult to improve the friction fastness. Therefore, it is preferable to include it in a non-aqueous ink.

--Dicarboxylic acid ester ---
Examples of the dicarboxylic acid ester include phthalate ester, adipate ester, polyester, sebacic acid ester, azelaic acid ester, maleic acid ester, succinic acid ester and the like.

--Tricarboxylic acid ester ---
Examples of the tricarboxylic acid ester include a trimet acid ester and a citric acid ester.

－－Phosphoric acid ester －－
Examples of the phosphoric acid ester include those represented by the general formula OP (OR) (OR') (OR "). In the general formula, R, R', R" are independently alkyl groups. , Cycloalkyl group, alkenyl group, and aryl group, which are further halogen atom (chlorine atom, bromine atom, fluorine atom, etc.), hydroxyl group, alkoxy group (carbon number 1 to 40, preferably, preferably. 1 or more and 20 or less), cyano group, aryloxy group (6 or more and 10 or less carbon atoms), alkyl group (1 or more and 40 or less carbon atoms, preferably 1 or more and 20 or less), alkoxy group (1 or more and 40 or less carbon atoms), It may be substituted with an alkoxycarbonyl group (2 or more and 42 or less carbon atoms). In addition, R, R', R "may be all the same substituents, all different substituents, or any two may be the same and only one different substituents.

The content of the plasticizer with respect to the total amount of the non-aqueous ink is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5% by mass or more and 50% by mass or less.
Further, the mass ratio (a / b) of the amount a of the resin particles contained in the water-based ink and the amount b of the plasticizer contained in the non-water-based ink applied per unit area of the recording medium is 10.3 / 1 or more. It is preferably 4.6 / 1 or less.

<Viscosity adjuster>
The viscosity adjusting agent is not particularly limited, but is a liquid that realizes a uniform solution or dispersion as a non-aqueous ink. Further, the non-aqueous ink is preferably 2 mPa · s or more and more preferably 3 mPa · s or more and 20 mPa · s or less at a viscosity of 25 ° C. so that the ink can be ejected by the inkjet head. The type of viscosity modifier and the content in the non-aqueous ink are appropriately selected so as to be within this viscosity range. Examples of the type of the viscosity adjusting agent include the organic solvent described in the above-mentioned water-based ink.

The content of the viscosity adjusting agent with respect to the total amount of the non-aqueous ink is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 50% by mass or more and 95% by mass or less.

<Manufacturing method of non-water-based ink>
As a method for producing a non-aqueous ink, for example, a plasticizer, a viscosity modifier, and if necessary, other components can be dispersed or dissolved, and appropriately stirred and mixed to produce the non-aqueous ink. As the stirring and mixing, for example, a sand mill, a homogenizer, a ball mill, a paint shaker, an ultrasonic disperser, a stirrer using a normal stirring blade, a magnetic stirrer, a high-speed disperser and the like can be used.

[Printing device, printing method]
The ink set of the present invention can be suitably used for various printing devices by an inkjet printing method, for example, a printer, a facsimile machine, a copying device, a printer / fax / copier multifunction device, a three-dimensional modeling device, and the like.
In the present application, the printing device and the printing method are devices capable of ejecting ink, various processing liquids, and the like to a recording medium, and a method of printing using the device. The recording medium means a medium to which ink and various treatment liquids can adhere even temporarily.
This printing device can include not only a head portion for ejecting ink, but also means related to feeding, transporting, and discharging paper of a recording medium, a pretreatment device, a device called a posttreatment device, and the like. ..
The printing apparatus and printing method may have a heating means used in the heating step.
Further, the printing apparatus and the printing method are not limited to those in which significant images such as characters and figures are visualized by ink. For example, those that form patterns such as geometric patterns and those that form three-dimensional images are also included.
Further, the printing 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.
An example of the printing apparatus will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective explanatory view of the device. FIG. 2 is a perspective explanatory view of the main tank. The image forming apparatus 400 as an example of the printing apparatus is a serial type image forming apparatus. A mechanism portion 420 is provided in the exterior 401 of the image forming apparatus 400. Each ink container of the main tank 410 (410x, 410c, 410m, 410y) that houses the non-water-based ink (X), the cyan water-based ink (C), the magenta water-based ink (M), and the yellow water-based ink (Y). 411 is formed of a packaging member such as an aluminum laminated film. The ink storage unit 411, which is one aspect of the ink storage container, is housed in, for example, a plastic storage container case 414.
On the other hand, a cartridge holder 404 is provided behind the opening when the cover 401c of the main body of the apparatus is opened. A main tank 410 is detachably attached to the cartridge holder 404. As a result, each ink ejection port 413 of the main tank 410 and the ejection head 434 for each ink communicate with each other via the supply tube 436 for each ink, and the ink can be ejected from the ejection head 434 to the recording medium.

Further, in the present application, the printing apparatus and the printing method have an application means and an application step for independently applying the water-based ink and the non-water-based ink to the recording medium so that the water-based ink and the non-water-based ink overlap each other. The order in which the water-based ink and the non-water-based ink are stacked is not particularly limited. When the water-based ink is applied to the recording medium and then the non-water-based ink is applied to the position where the water-based ink is applied, the non-water-based ink is applied to the recording medium and then the water-based ink is applied to the position where the non-water-based ink is applied. However, it is preferable to apply the water-based ink to the recording medium and then apply the non-water-based ink to the position where the water-based ink is applied. Since the water-based ink tends to have a higher specific gravity than the non-water-based ink, by first applying the water-based ink to the recording medium, the water-based ink sinks into the non-water-based ink, causing bleeding and image density. The decrease can be suppressed.

Further, in the application step using the application means, the mass ratio (A / B) of the amount A of the water-based ink applied and the amount B of the non-water-based ink per unit area of the recording medium is 1/1 or more. It is preferably 4/1 or more and 9/1 or less, more preferably. When the mass ratio (A / B) is 1/1 or more, the amount of the plasticizer derived from the non-aqueous ink does not become excessive as compared with the amount of the resin particles derived from the aqueous ink, and the ink film composed of the resin particles or the like does not become excessive. A plasticizer can be contained therein. As a result, it is possible to suppress the spread of the plasticizer outside the region to which the water-based ink is applied, and it is possible to suppress the bleeding of the image, which is the wet spread of the pigment caused by the spread of the plasticizer. Further, when the mass ratio (A / B) is 9/1 or less, the effect of improving the flexibility of the ink film by the plasticizer can be sufficiently exerted, and the frictional fastness of the image is improved. The above-mentioned unit area means, for example, the inside of an arbitrary 1 cm square area on a recording medium to which water-based ink and non-water-based ink are applied.

Further, in the present application, it is preferable that the printing apparatus and printing method include a drying means and a drying step for drying the ink applied to the recording medium. By drying the area to which the water-based ink and the non-water-based ink are applied, the plasticizer is contained in the formed ink film, and the effect of improving the flexibility of the ink film by the plasticizer can be fully exerted. Friction fastness is improved. When dried by heating, the temperature of the recording medium to which the water-based ink and the non-water-based ink is applied is preferably less than 100 ° C.

Further, in the present application, the printing apparatus and the printing method may have a heating means and a heating step for heating the ink applied to the recording medium, but it is preferable that the printing apparatus and the printing method do not have the heating means and the heating step. In the present application, the resin particles contained in the water-based ink function as a binder and form an ink film as the water evaporates, so that the pigment can be fixed on the recording medium even at room temperature, which does not require heating. be. By not heating, synthetic fibers such as socks made of a blend containing polyurethane and sportswear containing nylon, which are denatured by heat treatment and whose texture is impaired, can be used as a recording medium. The heating means and the heating step may be means and steps for heating and applying pressure. In addition, it is preferable not to heat the temperature of the recording medium to which the water-based ink and the non-water-based ink are applied to be 100 ° C. or higher. The heat treatment in the heating step may be not only the heat treatment based on the heating means of the printing device but also the heat treatment based on the heating device or the like prepared separately from the printing device.

The printing method in the present application is not limited to the inkjet printing method and can be widely used. In addition to the inkjet printing method, examples thereof include 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, and a spray coating method.

[recoding media]
The recording medium is preferably a base material having a fiber structure. Examples of the base material having a fiber structure include woven fabrics, knitted fabrics (knitted fabrics), laces, felts, and non-woven fabrics. The fibers constituting the fiber structure are, for example, cotton fibers, synthetic fibers, and blends thereof. The recording medium preferably contains synthetic fibers, and the synthetic fibers are more preferably fibers containing a polyurethane resin or a polyester resin. In the present application, as described above, printing can be performed without heat treatment, so that even if synthetic fibers are used as the recording medium, the fabric is not denatured and the texture is not impaired.

Hereinafter, examples of the present invention will be described, but the present invention is not limited to these examples.

<Example of manufacturing resin particles>
-Example of producing a polyether urethane resin emulsion-
In a nitrogen-substituted container equipped with a thermometer, a nitrogen gas introduction tube, and a stirrer, a polyether polyol (“PTMG1000” manufactured by Mitsubishi Chemical Corporation, average molecular weight: 1,000), 100.2 parts by mass, 2,2 -Dimethylol propionic acid 15.7 parts by mass, isophorone diisocyanate 48.0 parts by mass, methyl ethyl ketone 77.1 parts by mass as an organic solvent, and dibutyltin dileurate (hereinafter, also referred to as "DMTDL") 0. The reaction was carried out using 06 parts by mass. After continuing the reaction for 4 hours, 30.7 parts by mass of methyl ethyl ketone was supplied as a diluting solvent, and the reaction was further continued. When the average molecular weight of the reaction product reached the range of 20,000 or more and 60,000 or less, 1.4 parts by mass of methanol was added and the reaction was terminated to obtain an organic solvent solution of urethane resin. The carboxyl group of the urethane resin is neutralized by adding 13.4 parts by mass of a 48 mass% potassium hydroxide aqueous solution to the organic solvent solution of the urethane resin, then 715.3 parts by mass of water is added and the mixture is sufficiently stirred. By aging and removing the solvent, a polyether-based urethane resin emulsion (polyether-based urethane resin particle dispersion) having a solid content concentration of 30% by mass was obtained.
The minimum film-forming temperature of the obtained polyether urethane resin emulsion was measured using a film-forming temperature tester (manufactured by Imoto Seisakusho Co., Ltd.) and found to be 43 ° C.

<Preparation example of pigment dispersion liquid>
-Preparation example of black pigment dispersion-
After premixing the following formulation mixture, it was circulated and dispersed for 7 hours in a disc-type bead mill (KDL type of Simmal Enterprises, media: using zirconia balls having a diameter of 0.3 mm) to obtain a black pigment dispersion.
-Carbon black pigment (trade name: Monarch800, manufactured by Cabot) 15 parts by mass-Anionic surfactant (Pionin A-51-B, manufactured by Takemoto Oil & Fat Co., Ltd.) 2 parts by mass-Ion-exchanged water 83 parts by mass

<Preparation example of water-based ink>
-Preparation example of water-based ink 1-
Black pigment dispersion 20% by mass, polyether urethane resin emulsion (solid content concentration: 30% by mass) 36.33% by mass, 1,2-propanediol 20% by mass, 1,2-butanediol 2% by mass, 2 , 3-butanediol 2% by mass, 2-methyl-2,4-pentanediol 2% by mass, dipropylene glycol monomethyl ether 1% by mass, 3-methoxy-N, N-dimethylpropionamide (trade name: Equamid M-) 100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by mass, preservative (trade name: Proxel LV, manufactured by Abyssia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, trade name: Softanol EP-5035) , Nippon Catalyst Co., Ltd.) 0.01% by mass and 13.56% by mass of high pure water were mixed and stirred, and filtered with a polypropylene filter having an average pore size of 0.2 μm to prepare a water-based ink 1.

-Preparation example of water-based ink 2-
Black pigment dispersion 20% by mass, 1,2-propanediol 20% by mass, 1,2-butanediol 2% by mass, 2,3-butanediol 2% by mass, 2-methyl-2,4-pentanediol 2% by mass %, Dipropylene glycol monomethyl ether 1% by mass, 3-methoxy-N, N-dimethylpropionamide (trade name: Equamid M-100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by mass, preservative (trade name: Proxel LV, Abyssia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, trade name: Softanol EP-5035, manufactured by Nippon Catalyst Co., Ltd.) 0.01% by mass, and high pure water 49.89% by mass. Aqueous ink 2 was prepared by mixing and stirring and filtering with a polypropylene filter having an average pore size of 0.2 μm. The water-based ink 2 is different from the water-based ink 1 in that it does not contain the polyether urethane resin emulsion which is a resin particle.

-Preparation example of water-based ink 3-
Black pigment dispersion 20% by mass, polyether urethane resin emulsion (solid content concentration: 30% by mass) 36.33% by mass, 1,2-propanediol 20% by mass, 1,2-butanediol 2% by mass, 2 , 3-butanediol 2% by mass, 2-methyl-2,4-pentanediol 2% by mass, dipropylene glycol monomethyl ether 1% by mass, 3-methoxy-N, N-dimethylpropionamide (trade name: Equamid M-) 100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by mass, preservative (trade name: Proxel LV, manufactured by Abyssia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, trade name: Softanol EP-5035) , Nippon Catalyst Co., Ltd.) 0.01% by mass, stearate amide (trade name: Amid AP-1, manufactured by Nippon Kasei Co., Ltd.) 10% by mass, and high pure water 3.56% by mass are mixed and stirred, and the average pore size is 0. A water-based ink 3 was prepared by filtering with a 2 μm polypropylene filter. The water-based ink 3 differs from the water-based ink 1 in that it contains stearic acid amide, which is a plasticizer.

-Preparation example of water-based ink 4-
Stearic acid amide (trade name: Amide AP-1, manufactured by Nihon Kasei Co., Ltd.) 10% by mass, 1,2-propanediol 50% by mass, and high pure water 40% by mass are stirred and mixed to form a uniform solution, and the water-based ink 4 is prepared. Made.

<Preparation example of non-water-based ink>
-Preparation example of non-water-based ink 1-
Stearic acid amide (trade name: Amide AP-1, manufactured by Nihon Kasei Co., Ltd.) 10% by mass and 90% by mass of 1,2-propanediol were stirred and mixed to form a uniform solution, and a non-aqueous ink 1 was prepared.

-Preparation example of non-water-based ink 2-
Similar to non-aqueous ink 1, non-aqueous ink 1 except that 2-ethylhexyl stearate (trade name: Unistar MB876, manufactured by NOF CORPORATION) was used instead of stearic acid amide used in the production of non-aqueous ink 1. Aqueous ink 2 was obtained.

-Preparation example of non-water-based ink 3-
Non-water-based ink in the same manner as non-water-based ink 1 except that bis (2-ethylhexyl) adipate (manufactured by Taoka Chemical Industry Co., Ltd.) was used instead of stearic acid amide used in the production of non-water-based ink 1. I got 3.

-Preparation example of non-water-based ink 4-
Similar to non-aqueous ink 1, non-aqueous except that trimellitic acid tris (2-ethylhexyl) (manufactured by J-PLUS Co., Ltd.) was used instead of stearic acid amide used in the production of non-aqueous ink 1. Ink 4 was obtained.

-Preparation example of non-water-based ink 5-
A non-aqueous ink similar to the non-aqueous ink 1 except that tris (2-ethylhexyl) phosphate (manufactured by Daihachi Chemical Industry Co., Ltd.) was used instead of the stearic acid amide used in the production of the non-aqueous ink 1. I got 5.

-Preparation example of non-water-based ink 6-
The liquid consisting only of 1,2-propanediol was designated as the non-aqueous ink 6.

(Example 1)
An ink set in which the water-based ink 1 and the non-water-based ink 1 are combined is prepared, and the water-based ink 1 and the non-water-based ink 1 are filled in the ink container of an inkjet printer (trade name: IPSiO GXe5500, manufactured by Ricoh Co., Ltd.) for printing. Went. As a recording medium, a synthetic fiber (manufactured by Color Dyeing Co., Ltd.) produced by cross-knitting polyurethane and polyester at a ratio of 16:84 is used, cut into a rectangle of 210 mm × 297 mm, and conveyed by a printer for printing. Was done. As an image, a solid black image (200 mm × 200 mm square) was output. At this time, only the water-based ink was first applied to the recording medium, and then immediately (without going through the drying step), only the non-water-based ink was applied so as to be superimposed on the image formed by the water-based ink. After printing, the recording medium to which the water-based ink 1 and the non-water-based ink 1 were applied was placed in a dryer at 80 ° C. for 1 hour and dried to obtain a printed matter. In order to make it easier to transport the recording medium with a printer, copy paper (trade name: Type SA (Hakuri Paper) A4, manufactured by Ricoh Co., Ltd.) of the same size as the recording medium is pasted on the back side of the cut recording medium for printing. This copy paper was peeled off after printing and then dried.
The mass of each of the water-based ink 1 and the non-water-based ink 1 applied per unit area (1 cm square) of the recording medium is 90% by mass with respect to the total content of the water-based ink 1 and the non-water-based ink 1. It was 10% by mass.

(Examples 2 to 8, Comparative Examples 1 to 4)
In Example 1, the combination of the water-based ink and the non-water-based ink in the ink set is changed as shown in Table 1 below, and the masses of the water-based ink and the non-water-based ink applied to the recording medium are shown in Table 1 below. The printed matter of Examples 2 to 8 and Comparative Examples 1 to 4 was produced. The unit of each number in Table 1 is "mass%".

Next, the characteristics of the printed matter produced in Examples 1 to 8 and Comparative Examples 1 to 4 were evaluated according to the following methods and evaluation criteria. The results are shown in Table 2.

[Image density]
The produced printed matter is left to stand for 24 hours, and then, using a colorimeter (trade name: spectrophotometric densitometer X-Rite939, manufactured by X-Rite), the optical density (optical density) is applied at any five points in the printed image. Black) was measured, and the average value was evaluated according to the following criteria. It was judged that the case where the evaluation was C or higher was practical.
-Evaluation criteria-
A: Optical density (black) is 1.5 or more B: Optical density (black) is 1.3 or more and less than 1.5 C: Optical density (black) is 1.0 or more and less than 1.3 D: Optical density (black) ) Is less than 1.0

[Blur]
Before and after leaving the produced printed matter for 24 hours, by visually observing the edge of the printed image, the exudation distance of the exuded image portion with respect to the white background portion of the recording medium is measured, and the following criteria are used. Evaluated in. It was judged that the case where the evaluation was C or higher was practical.
-Evaluation criteria-
A: Almost no bleeding B: Bleeding less than 1 mm is seen C: Bleeding of 1 mm or more and less than 3 mm is seen D: Bleeding of 3 mm or more is seen

[Friction fastness]
The produced printed matter was left to stand for 24 hours, and the friction fastness was evaluated according to JIS L0849-II type. The friction cloth used was a cotton cloth (Kanakin No. 3), and a friction tester (trade name: AR-2 dyeing friction fastness tester, manufactured by INTEC Inc.) was used for friction. After rubbing, 5 points of the color transfer part to the cotton cloth where the color transfer density is high are visually judged by 0.5 mm square, and the colorimeter (trade name: spectroscopic colorimeter X-Rite939, X-Rite) The color was measured by (manufactured by the company), and the degree of color transfer, that is, the friction fastness, was evaluated by the average value of the optical density (black). It was judged that the case where the evaluation was C or higher was practical.
-Evaluation criteria-
A: Optical density of color transfer (black) in cotton cloth after rubbing is less than 0.15 B: Optical density of color transfer (black) in cotton cloth after rubbing is 0.15 or more and less than 0.30 C: Cotton cloth after rubbing The optical density (black) of color transfer in is 0.30 or more and less than 0.50 D: The optical density (black) of color transfer in cotton cloth after rubbing is 0.50 or more.

In Example 1, a plasticizer containing polyamide is used, and the image density is increased by the effect of the water-based ink containing resin particles, and bleeding does not occur. Further, the plasticizer obtains the plasticizing effect of the resin, the followability of the ink film to the recording medium is increased, and the ink film has a certain degree of friction fastness.
In Example 2, a plasticizer containing a monocarboxylic acid ester which is an ester compound is used, and the plasticizing effect is higher and the friction fastness is improved as compared with Example 1.
In Examples 3 to 5, plasticizers containing the ester compounds dicarboxylic acid ester, tricarboxylic acid ester, and phosphoric acid ester are used, respectively, and the plasticizing effect on the resin works well to improve the followability to the recording medium. Therefore, the image density is high, there is no bleeding, and the friction fastness is superior to that of Example 2.
Example 6 is an example in which the ink set of Example 3 is used and the ratio of the non-water-based ink is increased by changing the ratio of the water-based ink and the non-water-based ink at the time of printing. According to this example, it is possible to maintain a high rank of image density, bleeding, and friction fastness even if the amount of the non-aqueous ink is increased to some extent.
Example 7 is an example in which the ink set of Example 3 is used, and the ratio of the amount of the non-water-based ink applied is reduced by changing the ratio of the amount of the water-based ink and the non-water-based ink applied at the time of printing. According to this example, the plasticizing effect is slightly weakened, and although it is within a practical range, the friction fastness is slightly inferior to that of Examples 1 to 6.
Example 8 is an example in which the ratio of the amount of the non-aqueous ink applied is increased as compared with Example 6. According to this example, the ratio of the amount of the non-aqueous ink applied is slightly large, and the plasticizer cannot be completely contained in the ink film. Therefore, although it is within a practical range, the image is compared with Examples 1 to 6. Slightly inferior in concentration and bleeding. Further, the presence of oil on the image makes it easy for color transfer to occur, and although it is within a practical range, the friction fastness is slightly inferior to that of Examples 3 to 6.

400 Image forming device 401 Image forming device exterior 401c Device body cover 404 Cartridge holder 410 Main tank 410x, 410c, 410m, 410y Non-water-based ink (X), Cyan water-based ink (C), Magenta water-based ink (M) Main tank that stores yellow water-based ink (Y) 411 Ink storage unit 413 Ink discharge port 414 Storage container case 420 Mechanical unit 434 Discharge head 436 Supply tube

Japanese Unexamined Patent Publication No. 2006-083330

Claims (9)

It has a water-based ink containing water, an organic solvent, a pigment, and resin particles, and a non-water-based ink containing a plasticizer .
The plasticizer is an ester compound and is
The ester compound is an ink set which is at least one selected from the group consisting of a dicarboxylic acid ester, a tricarboxylic acid ester, and a phosphoric acid ester . A printing method comprising an application step of independently applying the water-based ink and the non-water-based ink to a recording medium so that the water-based ink and the non-water-based ink according to claim 1 overlap each other. In the application step, the mass ratio (A / B) of the amount A of the water-based ink and the amount B of the non-water-based ink applied per unit area of the recording medium is 4/1 or more and 9/1 or less. The printing method according to claim 2 . In the application step, the mass ratio (a / b) of the amount a of the resin particles contained in the water-based ink and the amount b of the plasticizer contained in the non-aqueous ink applied per unit area of the recording medium. Is the printing method according to claim 2 or 3 , wherein is 4.6 / 1 or more and 10.3 / 1 or less. The printing method according to any one of claims 2 to 4 , wherein the recording medium contains synthetic fibers. The printing method according to claim 5 , wherein the synthetic fiber is a fiber containing a polyurethane resin or a polyester resin. The printing method according to any one of claims 2 to 6 , wherein the printing method does not include a heating step for heating the recording medium after the application step. A storage container for independently storing the water-based ink and the non-water-based ink according to claim 1 .
A printing apparatus having an applying means for independently applying the water-based ink and the non-water-based ink to a recording medium so that the water-based ink and the non-water-based ink overlap each other. The printing device according to claim 8 , wherein the printing device does not have a heating means for heating the recording medium to which the water-based ink and the non-water-based ink are applied.

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