JP2019137794A - Ink set, printing method, and printer - Google Patents

Abstract

To overcome cases, in which feeling of fabric is deteriorated by modification when a heat treatment is conducted for suppressing bleeding when an ink is added and printed to a recording medium containing a synthetic fiber, in which image concentration is reduced in a method using a printing ink as a method for printing without heating the recording medium after printing, and in which a recording medium constituted by the fiber has high flexibility and deposited article is easy to be broken by movement of a fiber, and followability to the recording medium is deteriorated and friction fastness is poor in a disclosed method for forming a pigment aggregate containing a coloring material, a high molecular weight material, and a plasticizer on the recording medium, and further depositing the same.SOLUTION: There is provided an ink set having a water-based ink containing water, an organic solvent, a pigment, and a resin particle, and a non-water-based ink containing a plasticizer.SELECTED DRAWING: None

Description

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

  A method (DTG: Direct to Garment) for printing directly on a textile product such as a T-shirt with ink or the like is known. Such a printing method is characterized by high compatibility with small lots, a printed matter with high designability, and low environmental impact.

  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 heated at 100 ° C. or more to fix the color 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.

  As a method for printing without performing a heat treatment for heating the recording medium after printing, a method using a 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 discloses a first liquid containing at least a coloring material, a polymer substance, a water-soluble solvent, and water, at least a flocculant, a water-soluble solvent, and water. And an ink set for ink jetting that further contains a plasticizer 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 color 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 is highly flexible and the film-formed product is easily broken by the movement of the fibers. If the fixed material on the fiber surface is a pigment aggregate, the followability to the recording medium is inferior and the friction fastness is low. May be inferior.

  An object of the present invention is to provide an ink set capable of suppressing bleeding, having excellent image density, and excellent friction fastness.

  The invention according to claim 1 is an ink set having an aqueous ink containing water, an organic solvent, a pigment, and resin particles, and a non-aqueous ink containing a plasticizer.

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

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

  Hereinafter, embodiments of the present invention will be described.

[Ink set]
The ink set of the present invention includes an aqueous ink and a non-aqueous ink. Each of the water-based ink and the non-water-based ink may be one kind or plural kinds.

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

<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 the polyhydric alcohol 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- Hexanediol, ethyl-1,2,4-butanetriol, 1,2,3-butanetriol, 2,2,4-trimethyl-1,3-pentanediol, petriol, and the like.
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, propylene glycol monoethyl ether and the like.
Examples of polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether.
Examples of nitrogen-containing heterocyclic compounds 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 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, and triethylamine.
Examples of sulfur-containing compounds include dimethyl sulfoxide, sulfolane, thiodiethanol and the like.
Examples of other organic solvents include propylene carbonate and 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.

  Among organic solvents, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butane are used from the viewpoint of preventing aggregation of particles in aqueous ink. Diol, 2-methyl-2,4-pentanediol, and dipropylene glycol monomethyl ether are preferred. Also, 1,2-propanediol, 1,2-butanediol, and 2,3-butanediol having a boiling point of less than 200 ° C. from the viewpoint of promoting high scratch resistance, solvent resistance, and resin film formation. Is preferred.

  There is no restriction | limiting in particular as content of an organic solvent, 20 mass% or more and 70 mass% or less are preferable with respect to water-based ink whole quantity, and 30 mass% or more and 60 mass% or less are more preferable. When the content is 20% by mass or more and 70% by mass or less, the drying property is excellent and good ejection stability is obtained.

<Water>
There is no restriction | limiting in particular as water, According to the objective, it can select suitably, For example, pure water, such as ion-exchange water, ultrafiltration water, reverse osmosis water, distilled water, ultrapure water, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. The water content is preferably 15% by mass or more and 60% by mass or less, and 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, it is possible to prevent high viscosity and improve discharge stability.

<Pigment>
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 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 pigment such as gold or silver, a metallic pigment, or the like can be used.
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 pigments 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 metal pigments such as titanium oxide, and organic pigments such as 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, 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 content of the pigment is preferably 0.1% by mass or more and 10% by mass or less, and more 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, image density, fixability, and ejection stability can be improved.

As a method of obtaining 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 and dispersing the surface of the pigment with a resin, and a dispersing agent are 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 making it dispersible in water by adding a functional group such as a sulfone group or a carboxyl group to the pigment (for example, carbon) 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. It 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.
As the dispersant, RT-100 (nonionic surfactant) manufactured by Takemoto Yushi Co., Ltd. and Naphthalenesulfonic acid Na formalin condensate can also be suitably used as the dispersant.
A dispersing agent may be used individually by 1 type, or may use 2 or more types together.

<Pigment dispersion>
An ink can be obtained by mixing a material such as water or an organic solvent with a pigment. Further, 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 a material such as water or 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 is preferably 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 The content is preferably 50% by mass or less and more preferably 0.1% by mass or more and 30% by mass or less.
The pigment dispersion is preferably degassed by filtering coarse particles with a filter, a centrifugal separator or the like, if necessary.

<Resin particles>
The aqueous 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 to the recording medium even at room temperature where heating is not required.
As the resin particles, one kind may be used alone, or two or more kinds of resin particles may be used in combination. The resin particles are not particularly limited. For example, polyester resin particles; polyurethane resin particles; epoxy resin particles; polyamide resin particles; polyether resin particles; acrylic resin particles; acrylic-silicone resin particles; 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 addition synthetic resin particles; celluloses, Examples thereof include natural polymers such as rosins and natural rubber. As a resin particle, what was synthesize | combined suitably may be used and a commercial item may be used.

The resin particles are not particularly limited, but are preferably in an emulsion state using water as a dispersion medium. This makes it possible to easily obtain a water-based ink by mixing with a material such as a pigment or an organic solvent.
In dispersing the resin particles in the aqueous medium, a forced emulsification type using a dispersant can be used, but it can prevent the strength from being lowered due to the dispersant remaining in the coating film. A so-called self-emulsifying resin particle having an anionic group is 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 from the viewpoint of water dispersibility, abrasion resistance, and chemical resistance, and 5 mgKOH / mg or more and 50 mgKOH / mg. The following is more preferable.
Examples of the anionic group include a carboxyl group, a carboxylate group, a sulfonic acid group, and a sulfonate group. 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 water 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 an 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; metal base compounds containing Na, K, Li, Ca and the like. These may be used individually by 1 type and may use 2 or more types together.
As a method for producing an aqueous dispersion using forced emulsification type resin particles, for example, a surfactant such as a nonionic surfactant or an anionic surfactant can be used. These may be used individually by 1 type and may use 2 or more types together. Among these, nonionic surfactants are preferable from the viewpoint of water resistance.

The volume average particle size of the resin particles is preferably 10 nm to 1,000 nm, more preferably 10 nm to 200 nm, and particularly preferably 10 nm to 100 nm, particularly considering use in an ink jet printing apparatus. By using resin particles having a volume average particle size of 10 nm or more and 1,000 nm or less, the contact site between the organic solvent and the resin particle surface is increased, the film-forming property of the resin particles is increased, and a continuous film of tough resin is formed. Since it is formed, high image hardness can be obtained. The volume average particle diameter can be measured using, for example, a particle size analyzer (Microtrack MODEL UPA9340, manufactured by Nikkiso Co., Ltd.).
There is no restriction | limiting in particular as content of resin, Although it can select suitably according to the objective, 1 mass% or more and 30 mass% or less are preferable with respect to the water-based ink whole quantity, and 5 mass% or more and 20 mass% or less. Is more preferable.

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

<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. Examples of the silicone surfactant include side chain modified polydimethylsiloxane, both terminal modified polydimethylsiloxane, one terminal modified polydimethylsiloxane, and side chain both terminal modified polydimethylsiloxane. Those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group are particularly preferred because they exhibit good properties as an aqueous surfactant. Moreover, a polyether modified silicone surfactant can also be used as a silicone surfactant, for example, the compound etc. which introduce | transduced the polyalkylene oxide structure into the Si part side chain of dimethylsiloxane are mentioned.
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 and perfluoroalkyl sulfonate. Examples of the perfluoroalkyl carboxylic acid compound include perfluoroalkyl carboxylic acid and perfluoroalkyl carboxylate. 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 polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group in the side chain. Examples thereof include salts of oxyalkylene 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 chain Examples thereof include polydimethylsiloxane modified at both ends, and a polyether-modified silicone surfactant having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modifying group is particularly preferable because it exhibits good properties as an aqueous surfactant. .
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 a general formula (S-1) type | formula is dimethylpolyethylene. Examples thereof include those introduced into the side chain of Si part of siloxane.
(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 Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.), 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 fluorosurfactant include perfluoroalkyl phosphate compounds, perfluoroalkylethylene oxide adducts, and 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.
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 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); 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 (Omnova) Manufactured), Unidyne DSN-403N (produced by Daikin Industries, Ltd.) and the like. Among these, good print quality, particularly color developability, penetrability to paper, wettability, and leveling are significantly improved. FS-3100, FS-34, FS-300 manufactured by Chemours, FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by Neos Co., Ltd. Particularly preferred are Fox PF-151N and Unidyne DSN-403N manufactured by Daikin Industries, Ltd.

  There is no restriction | limiting in particular as content of surfactant in an ink, Although it can select suitably according to the objective, From the point which is excellent in wettability and discharge stability, and image quality improves, it is 0.001 mass. % To 5% by mass is preferable, and 0.05% 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 fungicide>
The antiseptic / antifungal agent is not particularly limited, and examples thereof include 1,2-benzisothiazolin-3-one.

<Rust preventive>
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.

<Viscosity>
The viscosity of the water-based ink is preferably 2 mPa · s or more and 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, ejection stability can be improved.

<Method for producing water-based ink>
As a method for producing a 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 mixed with stirring. it 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 stirrer blade, a magnetic stirrer, a high-speed disperser, or the like can be used.

<< Non-aqueous ink >>
The non-aqueous ink contains a plasticizer and optionally contains other components such as a viscosity modifier. The non-aqueous ink means an ink composition that does not substantially contain 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 preferable that it is 0.5% or less.

<Plasticizer>
A plasticizer is a compound that has the effect of lowering the glass transition temperature (Tg) of a 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 including the plasticizer in the non-aqueous ink in the ink film formed of the aqueous ink containing the resin particles. Reduce. As a result, an ink film containing a plasticizer is formed, and the ink film is softened by the plasticizing effect of the plasticizer, thereby improving the followability of the ink film with respect to the movement of the recording medium, and improving the friction fastness of the printed image area. improves. Note that, as in the present application, by adding a plasticizer to a non-aqueous 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. Ink bleeding can be suppressed.
The plasticizer preferably has a function of lowering the Tg of the resin constituting the resin particles contained in the aqueous 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 obtained by mixing the resin constituting the resin particles contained in the aqueous ink and the plasticizer contained in the non-aqueous ink at the mass ratio P is room temperature (25 ° C.) or less. Is preferred. In addition, as a method of making Tg of the said resin below room temperature (25 degreeC) using a plasticizer, the method of adjusting the content of the plasticizer in non-aqueous ink, the method of selecting the kind of plasticizer, etc. are mentioned. However, it is not particularly limited.
Examples of the plasticizer include compounds such as esters, amides, ethers, alcohols, lactones, and polyethyleneoxy. Among these, it is preferable to use an ester compound. One type of plasticizer may be used, or two or more types of plasticizers may be used.

-Ester compound-
As the ester compound, any of monocarboxylic acid ester, dicarboxylic acid ester, tricarboxylic acid ester, and phosphoric acid ester 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 water-based ink to the recording medium, lengthens the intermolecular distance between the resin molecules, and improves the flexibility of the ink film. It is thought that it is effective. Therefore, among the ester compounds, those having a linear and long structure and a spatially bulky structure such as dicarboxylic acid ester, tricarboxylic acid ester, and phosphoric acid ester are preferable. However, a plasticizer having such a structure has low water solubility, and it is difficult to contain a large amount in a water-soluble medium. Therefore, even if a plasticizer is contained in an aqueous medium rather than a non-aqueous ink, the resin cannot be sufficiently plasticized, and as a result, it may be difficult to increase friction fastness. Therefore, it is preferably contained in the non-aqueous ink.

--Dicarboxylic acid ester--
Examples of the dicarboxylic acid ester include phthalic acid ester, adipic acid ester, polyester, sebacic acid ester, azelaic acid ester, maleic acid ester, and succinic acid ester.

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

--Phosphate ester--
Examples of the phosphate ester include those represented by the general formula OP (OR) (OR ′) (OR ″). In the general formula, R, R ′, and R ″ each independently represent an alkyl group. , A cycloalkyl group, an alkenyl group, and an aryl group, which further include a halogen atom (a chlorine atom, a bromine atom, a fluorine atom, etc.), a hydroxyl group, and an alkoxy group (having 1 to 40 carbon atoms, preferably 1 to 20), a cyano group, an aryloxy group (6 to 10 carbon atoms), an alkyl group (1 to 40 carbon atoms, preferably 1 to 20 carbon atoms), an alkenyl group (1 to 40 carbon atoms), It may be substituted with an alkoxycarbonyl group (having 2 to 42 carbon atoms). R, R ′, and R ″ may all be the same substituent, may be all different substituents, or any two may be the same and only one different substituent.

There is no restriction | limiting in particular in content of the plasticizer with respect to nonaqueous ink whole quantity, Although it can select suitably according to the objective, 5 mass% or more and 50 mass% or less are preferable.
The mass ratio (a / b) of the amount a of the resin particles contained in the aqueous ink applied per unit area of the recording medium and the amount b of the plasticizer contained in the non-aqueous ink is 10.3 / 1 or more. It is preferable that it is 4.6 / 1 or less.

<Viscosity modifier>
Although it does not specifically limit as a viscosity modifier, It is a liquid which implement | achieves a uniform solution or dispersion liquid as 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 25 ° C. so that it can be ejected by an inkjet head. The viscosity regulator and the content in the non-aqueous ink are appropriately selected so that the viscosity is within this viscosity range. As a kind of viscosity modifier, the organic solvent etc. which were demonstrated in said aqueous ink are mentioned, for example.

  The content of the viscosity modifier 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.

<Method for producing non-aqueous 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 agitated and mixed. 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 stirrer blade, a magnetic stirrer, a high-speed disperser, or the like can be used.

[Printing device, printing method]
The ink set of the present invention can be suitably used for various printing apparatuses using an ink jet printing method, such as a printer, a facsimile apparatus, a copying apparatus, a printer / fax / copier multifunction machine, and a three-dimensional modeling apparatus.
In the present application, a printing apparatus and a printing method are an apparatus that can eject ink, various processing liquids, and the like onto a recording medium, and a method that performs printing using the apparatus. The recording medium means a medium on which ink or various processing liquids can be temporarily attached.
This printing apparatus can include not only the head portion that ejects ink, but also means for feeding, transporting, and discharging the recording medium, and other devices called pre-processing devices and post-processing devices. .
The printing apparatus and the printing method may include a heating unit used in the heating process.
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, what forms patterns, such as a geometric pattern, etc. includes what forms a three-dimensional image.
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. 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 printing 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 of the main tank 410 (410x, 410c, 410m, 410y) that stores the non-aqueous ink (X), the cyan aqueous ink (C), the magenta aqueous ink (M), and the yellow aqueous ink (Y). 411 is formed of a packaging member such as an aluminum laminate film. The ink storage portion 411 which is an aspect of the ink storage container is stored in, for example, a plastic storage container case 414.
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. As a result, the ink discharge ports 413 of the main tank 410 and the ink ejection heads 434 communicate with each other via the ink supply tubes 436, and ink can be ejected from the ejection heads 434 to the recording medium.

  In addition, in the present application, the printing apparatus and the printing method include an applying unit and an applying process for applying the aqueous ink and the non-aqueous ink to the recording medium independently so that the aqueous ink and the non-aqueous 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 water-based ink is applied to a recording medium and then non-aqueous ink is applied to a position where the water-based ink is applied, the non-aqueous ink is applied to the recording medium, and then the water-based ink is applied to the position where the non-aqueous ink is applied. However, it is preferable to apply the water-based ink to the recording medium and then apply the non-aqueous ink to the position where the water-based ink is applied. Since the specific gravity of water-based ink tends to be larger than that of non-aqueous ink, the water-based ink sinks into the non-water-based ink by applying the water-based ink first to the recording medium. The decrease can be suppressed.

  Further, in the applying step using the applying means, the mass ratio (A / B) of the amount A of the water-based ink and the amount B of the non-aqueous ink applied per unit area of the recording medium is 1/1 or more. Preferably, it is 4/1 or more and 9/1 or less. When the mass ratio (A / B) is 1/1 or more, the amount of the plasticizer derived from the non-aqueous ink is not excessive as compared with the amount of the resin particles derived from the aqueous ink, and the ink film is composed of resin particles or the like. A plasticizer can be contained therein. Thereby, it is possible to suppress the plasticizer from spreading outside the region to which the water-based ink has been applied, and it is possible to suppress the blurring of the image, which is the wetting and spreading of the pigment caused by the spread of the plasticizer. Further, if 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 friction fastness of the image is improved. The unit area is, for example, an arbitrary 1 cm square area on a recording medium to which water-based ink and non-water-based ink are applied.

  In the present application, the printing apparatus and the printing method preferably include a drying unit and a drying process for drying the ink applied to the recording medium. By drying the region to which the water-based ink and the non-water-based ink are applied, a plasticizer is contained in the formed ink film, and the effect of improving the flexibility of the ink film by the plasticizer can be sufficiently exerted. Friction fastness is improved. In addition, when drying by heating, it is preferable that the temperature of the recording medium provided with the water-based ink and the non-water-based ink is less than 100 ° C.

  In the present application, the printing apparatus and the printing method may include a heating unit and a heating step for heating the ink applied to the recording medium, but preferably do not include the heating unit and the heating step. In the present application, since the resin particles contained in the water-based ink function as a binder and the ink film is formed as the water evaporates, the pigment can be fixed to the recording medium even at room temperature that does not require heating. is there. By not heating, synthetic fibers, such as socks made of a blend containing polyurethane and sportswear containing nylon, can be used as a recording medium in which the fabric is modified and the texture is impaired by heat treatment. In addition, as a heating means and a heating process, the means and process which apply a pressure while heating may be sufficient. In addition, it is preferable not to make the temperature of the recording medium provided with water-based ink and non-water-based ink 100 ° C. or higher. Note that the heat treatment in the heating step is not limited to the heat treatment based on the heating means of the printing apparatus, but may be a heat treatment based on a heating apparatus or the like prepared separately from the printing apparatus.

  The printing method in the present application is not limited to the ink jet printing method, and can be widely used. In addition to the inkjet printing 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 given.

[recoding media]
The recording medium is preferably a substrate having a fiber structure. Examples of the substrate having a fiber structure include woven fabric, knitted fabric (knitted fabric), lace, felt, and non-woven fabric. Moreover, the fiber which comprises a fiber structure is a cotton fiber, a synthetic fiber, and these blends, for example. The recording medium preferably contains a synthetic fiber, and the synthetic fiber is more preferably a fiber containing a polyurethane resin or a polyester resin. In the present application, as described above, printing can be performed without performing heat treatment, and therefore, even if synthetic fibers are used as the recording medium, the fabric is not modified and the texture is not impaired.

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

<Production example of resin particles>
-Preparation example of polyether urethane resin emulsion-
In a nitrogen-substituted container equipped with a thermometer, a nitrogen gas introduction tube, and a stirrer, polyether polyol ("PTMG1000" manufactured by Mitsubishi Chemical Corporation, average molecular weight: 1,000) 100.2 parts by mass, 2, 2 -15.7 parts by mass of dimethylolpropionic acid, 48.0 parts by mass of isophorone diisocyanate, 77.1 parts by mass of methyl ethyl ketone as an organic solvent, and dibutyltin direureate (hereinafter also referred to as "DMTDL") as a catalyst. The reaction was carried out using 06 parts by mass. After the reaction was continued for 4 hours, 30.7 parts by mass of methyl ethyl ketone was supplied as a diluent solvent, and the reaction was further continued. When the average molecular weight of the reaction product reached a range of 20,000 to 60,000, 1.4 parts by mass of methanol was added to terminate the reaction, thereby obtaining an organic solvent solution of urethane resin. After neutralizing the carboxyl group of the urethane resin by adding 13.4 parts by weight of a 48% by weight aqueous potassium hydroxide solution to the organic solvent solution of the urethane resin, then adding 715.3 parts by weight of water and stirring sufficiently, By aging and removing the solvent, a polyether urethane resin emulsion (polyether urethane resin particle dispersion) having a solid content concentration of 30% by mass was obtained.
About the obtained polyether-type urethane resin emulsion, when the minimum film-forming temperature was measured using the film-forming temperature test apparatus (made by Imoto Seisakusho Co., Ltd.), it was 43 degreeC.

<Preparation example of pigment dispersion>
-Preparation example of black pigment dispersion-
The following prescription mixture was premixed and then circulated and dispersed for 7 hours in a disk type bead mill (Shinmaru Enterprises KDL type, media: 0.3 mm diameter zirconia ball used) to obtain a black pigment dispersion.
Carbon black pigment (trade name: Monarch 800, manufactured by Cabot Corporation) 15 parts by mass Anionic surfactant (Pionin A-51-B, manufactured by Takemoto Yushi 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: Ecamide M- 100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by mass, preservative (trade name: Proxel LV, manufactured by Avicia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, product name: Softanol EP-5035) , Manufactured by Nippon Shokubai Co., Ltd.) 0.01% by mass and 13.56% by mass of high-purity water were mixed and stirred, and an average pore size of 0.2 μm polyp To prepare an aqueous ink 1 by filtration at pyrene filter.

-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: Ecamide M-100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by weight, preservative (trade name: Proxel LV, Avicia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, trade name: Softanol EP-5035, manufactured by Nippon Shokubai Co., Ltd.) 0.01% by mass, and high purity water 49.89% by mass Water-based ink 2 was prepared by mixing and stirring, and filtering with a polypropylene filter having an average pore size of 0.2 μm. This water-based ink 2 is different from the water-based ink 1 in that it does not contain a polyether-based urethane resin emulsion that is resin particles.

-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: Ecamide M- 100, manufactured by Idemitsu Kosan Co., Ltd.) 3% by mass, preservative (trade name: Proxel LV, manufactured by Avicia Co., Ltd.) 0.1% by mass, surfactant (alcohol ethoxylate surfactant, product name: Softanol EP-5035) , Manufactured by Nippon Shokubai Co., Ltd.) 0.01% by mass, stearic acid amide (trade name: Amide AP-1, Nippon Kasei Co., Ltd.) ) 10 wt%, and then mixed and stirred 3.56 wt% high purity water to prepare an aqueous ink 3 by filtration at an average pore diameter of 0.2μm polypropylene filter. This water-based ink 3 is different from the water-based ink 1 in that it contains stearic acid amide which is a plasticizer.

-Preparation example of water-based ink 4-
Stirrate amide (trade name: Amide AP-1, manufactured by Nippon Kasei Co., Ltd.) 10% by weight, 1,2-propanediol 50% by weight, and high-purity water 40% by weight are stirred and mixed to obtain a uniform solution. Produced.

<Preparation example of non-aqueous ink>
-Preparation example of non-aqueous ink 1-
Nonaqueous ink 1 was prepared by stirring and mixing stearic acid amide (trade name: Amide AP-1, Nippon Kasei Co., Ltd.) 10% by mass and 1,2-propanediol 90% by mass to obtain a uniform solution.

-Preparation example of non-aqueous ink 2-
Non-aqueous ink 1 was used in the same manner as 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 preparation of non-aqueous ink 1. A water-based ink 2 was obtained.

-Preparation example of non-aqueous ink 3-
The non-aqueous ink is the same as the non-aqueous ink 1 except that bis (2-ethylhexyl) adipate (Taoka Chemical Co., Ltd.) is used instead of the stearic acid amide used in the preparation of the non-aqueous ink 1. 3 was obtained.

-Preparation example of non-aqueous ink 4-
The non-aqueous ink 1 was used in the same manner as the non-aqueous ink 1 except that trimellitic acid tris (2-ethylhexyl) (manufactured by J Plus Co., Ltd.) was used instead of the stearic acid amide used in the preparation of the non-aqueous ink 1. Ink 4 was obtained.

-Preparation example of non-aqueous ink 5-
The non-aqueous ink is the same as the non-aqueous ink 1 except that tris (2-ethylhexyl) phosphate (manufactured by Daihachi Chemical Industry Co., Ltd.) is used instead of the stearic acid amide used in the preparation of the non-aqueous ink 1. 5 was obtained.

-Preparation example of non-aqueous ink 6-
A liquid consisting only of 1,2-propanediol was designated as non-aqueous ink 6.

Example 1
An ink set is prepared by combining water-based ink 1 and non-water-based ink 1, and water-based ink 1 and non-water-based ink 1 are filled in an ink storage container of an ink jet printer (trade name: IPSiO GXe5500, manufactured by Ricoh Co., Ltd.) for printing. Went. As a recording medium, synthetic fiber (manufactured by Color Dyeing Co., Ltd.) produced by knitting polyurethane and polyester at a ratio of 16:84 is used, cut into a 210 mm × 297 mm rectangle, printed by a printer. Went. A black solid image (200 mm × 200 mm square) was output as the image. At this time, only the water-based ink was first applied to the recording medium, and immediately thereafter (without passing through the drying step), only the non-water-based ink was applied so as to overlap the image formed with the water-based ink. After printing, the recording medium provided with the water-based ink 1 and the non-water-based ink 1 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 of the same size as the recording medium (trade name: type SA (development paper) A4, manufactured by Ricoh Co., Ltd.) is printed on the back side of the cut recording medium. The copy paper was peeled off after printing and dried.
The mass of each of the water-based ink 1 and the non-aqueous 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-aqueous ink 1. It was 10 mass%.

(Examples 2-8, Comparative Examples 1-4)
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 mass of each of the water-based ink and the water-based ink applied to the recording medium is shown in Table 1 below. The printed matter of Examples 2-8 and Comparative Examples 1-4 was produced. In addition, the unit of each number in Table 1 is “mass%”.

  Next, the characteristics of the printed materials 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 allowed to stand for 24 hours, and thereafter, using a colorimeter (trade name: spectrocolorimetric densitometer X-Rite 939, manufactured by X-Rite), optical density (in five arbitrary positions in the printed image ( Black) was measured and the average value was evaluated according to the following criteria. The case where evaluation was C or more was judged to be 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

[Smear]
Before and after leaving the produced printed matter for 24 hours, the edge of the printed image is visually observed to measure the exuding distance of the image portion that exudes to the white background portion of the recording medium. It was evaluated with. The case where evaluation was C or more was judged to be practical.
-Evaluation criteria-
A: Almost no bleeding B: Bleeding less than 1 mm C: Bleeding 1 mm or more and less than 3 mm D: Bleeding 3 mm or more

[Friction fastness]
The produced printed matter was allowed to stand for 24 hours, and the friction fastness was evaluated according to JIS L0849-II type. The friction cloth used was cotton cloth (Kanakin No. 3), and the friction was measured using a friction test apparatus (trade name: AR-2 dyeing friction fastness tester, manufactured by INTEC Co., Ltd.). After the rubbing, among the color transfer portions to the cotton cloth, five locations with a high color transfer density are visually determined on a 0.5 mm square, and a colorimeter (trade name: spectral colorimetry densitometer X-Rite939, X-Rite). The color transfer degree, that is, the fastness to friction was evaluated by the average value of the optical density (black). The case where evaluation was C or more was judged to be practical.
-Evaluation criteria-
A: Optical density (black) of color transfer in cotton fabric after friction is less than 0.15 B: Optical density (black) of color transfer in cotton fabric after friction is 0.15 or more and less than 0.30 C: Cotton fabric after friction The color transfer optical density (black) at 0.30 or more and less than 0.50 D: The color transfer optical density (black) of the cotton fabric after friction 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 no blur is generated. Further, the plasticizing effect of the resin is obtained by the plasticizer, the followability of the ink film with respect to the recording medium is increased, and a certain degree of friction fastness is obtained.
Example 2 uses a plasticizer containing a monocarboxylic acid ester, which is an ester compound. Compared to Example 1, the plasticizing effect is high and the friction fastness is improved.
Examples 3 to 5 use plasticizers including dicarboxylic acid esters, tricarboxylic acid esters, and phosphoric acid esters, which are ester compounds, respectively, and improve the followability to the recording medium by having a good plasticizing effect on the resin. Therefore, in all cases, the image density is high, there is no blur, and the fastness to friction is superior to that of Example 2.
Example 6 is an example in which the ink set of Example 3 was used and the ratio of the non-aqueous ink was increased by changing the ratio of the aqueous ink and the non-aqueous ink during printing. According to this example, even if the amount of non-aqueous ink is increased to some extent, it is possible to maintain a high rank of image density, bleeding, and friction fastness.
Example 7 is an example in which the ink set of Example 3 was used and the ratio of the applied amount of the non-aqueous ink was decreased by changing the ratio of the applied amount of the aqueous ink and the non-aqueous ink at the time of printing. According to this example, the plastic effect is slightly weakened and the friction fastness is slightly inferior to those of Examples 1 to 6, although it is within a practical range.
Example 8 is an example in which the ratio of the applied amount of non-aqueous ink is increased as compared with Example 6. According to this example, the ratio of the applied amount of the non-aqueous ink is slightly increased, and the plastic film cannot be contained in the ink film. Concentration and bleeding are slightly inferior. 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 Examples 3-6.

400 Image forming apparatus 401 Exterior of image forming apparatus 401c Cover of apparatus main body 404 Cartridge holder 410 Main tank 410x, 410c, 410m, 410y Non-aqueous ink (X), cyan aqueous ink (C), magenta aqueous ink (M) , A main tank for storing yellow water-based ink (Y), 411, an ink storage section, 413, an ink discharge port, 414, a storage container case, 420, a mechanism section, 434, a discharge head, and a supply tube.

JP 2006-083303 A

Claims (11)

  An ink set having an aqueous ink containing water, an organic solvent, a pigment, and resin particles, and a non-aqueous ink containing a plasticizer.   The ink set according to claim 1, wherein the plasticizer is an ester compound.   The ink set according to claim 2, wherein the ester compound 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 applying step of independently applying the water-based ink and the non-aqueous ink to a recording medium so that the water-based ink and the non-aqueous ink according to claim 1 overlap each other.   In the applying step, the mass ratio (A / B) of the amount A of the water-based ink and the amount B of the non-aqueous 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 4.   In the applying step, the mass ratio (a / b) of the amount a of the resin particles contained in the aqueous ink applied per unit area of the recording medium and the amount b of the plasticizer contained in the non-aqueous ink. The printing method according to claim 4 or 5, wherein is 10.3 / 1 or more and 4.6 / 1 or less.   The printing method according to claim 4, wherein the recording medium includes a synthetic fiber.   The printing method according to claim 7, wherein the synthetic fiber is a fiber containing a polyurethane resin or a polyester resin.   The printing method according to claim 4, wherein the printing method does not include a heating step of heating the recording medium after the applying step. A container for independently containing the water-based ink and the non-water-based ink according to any one of claims 1 to 3,
A printing apparatus comprising: an applying unit that applies the water-based ink and the non-water-based ink to a recording medium independently such that the water-based ink and the non-water-based ink overlap each other.   The printing apparatus according to claim 10, wherein the printing apparatus does not include a heating unit that heats the recording medium to which the water-based ink and the non-water-based ink are applied.