Recording device

Abstract

To provide a recording device which prevents curling in thin paper, and is excellent in dryness in thick paper.SOLUTION: A recording device includes ink which contains a coloring material, an organic solvent and water and contains 3.0 mass% or more and 15.0 mass% or less of an organic solvent having a boiling point of 210°C or higher and 280°C or lower in the ink, discharge means 3 for discharging the ink to a recording medium, conveyance means 1, 2 and 7 for conveying the recording medium, heating means 4 for irradiating the recording medium to which the ink is imparted with light and heating the recording medium, and exhaust means 6 for exhausting air in a housing, and generates such an air flow that vapor generated by heating with the heating means comes in contact with the recording medium before heating, when the vapor generated by heating is exhausted from the exhaust means.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a recording apparatus. [Background technology]

[0002] Inkjet printers have the advantages of low noise, low running costs, and easy color printing, and are widely used as output devices for digital signals. As printing substrates for inkjet printers, absorbent media such as plain paper, low absorbent recording media such as coated paper, and non-absorbent recording media such as plastic films are used. In recent years, there has been a demand for faster printing, especially in the field of commercial printing, and inks and devices that can dry in a shorter time have been developed.

[0003] Patent Document 1 discloses an aqueous inkjet ink that contains a pigment, a pigment dispersion resin, an organic solvent, and water, and the organic solvent contains (A) a water-soluble organic solvent having a boiling point of 100° C. or more and 180° C. or less, and (B) an organic solvent having a boiling point of 200° C. or more and 280° C. or less and a surface tension of 20 mN / m or more and 30 mN / m or less. Patent Document 1 discloses that the ink has excellent printability on general printing substrates, particularly substrates with high gloss such as coated paper, art paper, and polyvinyl chloride sheet, and is capable of producing high quality images.

[0004] Patent Document 2 discloses a drying device that includes a light irradiation unit that irradiates a moving recording medium with light and evaporates moisture from droplets attached to the recording medium, an outlet that is located downstream of the light irradiation unit in the recording medium movement direction and that discharges air to be supplied to the recording medium and has a downstream end on the downstream side in the recording medium movement direction, and a heating unit that heats a portion of the recording medium that is located upstream of the downstream end. Patent Document 2 discloses that it is possible to suppress a decrease in the temperature of the recording medium caused by supplying air to the recording medium, compared to a case in which a heating unit that heats the recording medium is not provided. Summary of the Invention [Problem to be solved by the invention]

[0005] However, although Patent Document 1 predicts that curl resistance will be improved by including an organic solvent with a boiling point of 200° C. or more and 280° C. or less, drying properties may be insufficient depending on the drying process. Also, it is difficult to obtain good drying properties for cardboard. In Patent Document 2, it seems that the steam generated by heating comes into contact with the recording medium, which can suppress curling such as wrinkling of the paper caused by heating. However, in Patent Document 2, the light irradiation unit and the discharge port are on the same side of the recording medium, so this does not allow sufficient moisture absorption. For this reason, it is thought that the steam generated by heating only brushes the surface of the recording medium, and moisture absorption by the recording medium is insufficient to increase the heating efficiency by light irradiation. In the prior art, when trying to improve the drying properties of thick paper, curling occurs in thin paper, while when trying to prevent curling in thin paper, there is a problem that the thick paper cannot be dried sufficiently.

[0006] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a recording device that does not curl thin paper and has excellent drying properties when used with thick paper. [Means for solving the problem]

[0007] In order to solve the above problems, the recording device of the present invention comprises an ink that contains a colorant, an organic solvent, and water, and contains 3.0% by mass or more and 15.0% by mass or less of an organic solvent having a boiling point of 210°C or more and 280°C or less, an ejection means for ejecting the ink onto a recording medium, a transport means for transporting the recording medium, a heating means for irradiating the recording medium to which the ink has been applied with light to heat it, and an exhaust means for exhausting air from within a housing, and is characterized in that when steam generated by heating with the heating means is exhausted from the exhaust means, an air current is generated such that the steam generated by heating comes into contact with the recording medium before it is heated. Effect of the Invention

[0008] According to the present invention, it is possible to provide a recording device that does not curl thin paper and has excellent drying properties when used with thick paper. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of a recording apparatus according to the present invention. [Diagram 2] FIG. 2 is a schematic diagram for illustrating an example of an air flow. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The recording device according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the following embodiment, and may be modified, added, modified, deleted, or otherwise altered within the scope of what a person skilled in the art can conceive, and any aspect of the present invention is within the scope of the present invention as long as it provides the functions and effects of the present invention.

[0011] The recording device of the present invention comprises ink that contains a colorant, an organic solvent, and water, and contains 3.0% by mass or more and 15.0% by mass or less of an organic solvent having a boiling point of 210°C or more and 280°C or less, an ejection means for ejecting the ink onto a recording medium, a transport means for transporting the recording medium, a heating means for irradiating the recording medium to which the ink has been applied with light to heat it, and an exhaust means for exhausting air from within a housing, and is characterized in that when steam generated by heating with the heating means is exhausted from the exhaust means, an air current is generated such that the steam generated by heating comes into contact with the recording medium before it is heated. The recording apparatus of the present invention may be called an image forming apparatus, an inkjet recording apparatus, an inkjet printer, a modeling apparatus, or the like.

[0012] An embodiment of a recording apparatus will be described with reference to Fig. 1. Fig. 1 is a schematic diagram of the main part of the recording apparatus of this embodiment.

[0013] The conveying means in this embodiment includes, for example, a paper feeder 1, a winding device 2, and a roller 7. The recording medium (web of paper P) is conveyed between the paper feeder 1 and the winding device 2, comes into contact with roller 7, which is a conveying member, and is conveyed in the direction of the arrow. Note that only one roller 7 is given a reference number, and the reference numbers for the other rollers are omitted. Furthermore, the configuration of roller 7 is not limited to that shown in the figure, and can be changed as appropriate, for example, the number, arrangement, etc. can be changed as appropriate.

[0014] The inkjet head 3 is an example of a discharging means, and discharges ink onto a recording medium. The ink to be discharged and the configuration of the inkjet head can be appropriately selected. In the illustrated example, for example, there are four inkjet heads, each of which discharges a different color ink (K, C, M, Y).

[0015] The IR heater 4 is an example of a heating means, and irradiates light onto the recording medium onto which the ink has been ejected. By irradiating light and heating, the water-based ink can be dried well. The light is preferably IR light, which is in a wavelength range absorbed by water, and in this case, the ink can be dried quickly.

[0016] The exhaust means exhausts the air inside the housing. The exhaust means in this embodiment has, for example, an exhaust duct 6, a fan, etc. The exhaust duct 6 has an intake port for sucking in the air inside the housing, an exhaust port for exhausting the air, etc.

[0017] According to the recording device of this embodiment, when the steam generated by heating by the heating means is exhausted from the exhaust means, an air flow is generated such that the steam generated by heating comes into contact with the recording medium before it is heated. In this embodiment, the high humidity air generated from the image when heated by the IR heater 4 is sucked into the exhaust duct 6, so that the recording medium before it is heated and being transported can absorb the steam. Then, the recording medium that has absorbed the steam is transported to the heating position of the IR heater 4 and heated by the IR heater 4, so that the absorbed moisture generates heat by itself and the recording medium can be thoroughly dried from the inside. Therefore, by making the recording medium absorb the steam, the drying property can be improved even if the recording medium is cardboard.

[0018] On the other hand, when the recording medium is thin paper, the moisture in the paper evaporates due to heating, causing curling. Therefore, the present inventors conducted intensive research and found it necessary to adopt an organic solvent that has a curl suppressing effect as an ink component. As a result of further research, the present invention was reached as it was found that curling can be suppressed by using an ink containing 3.0% by mass to 15.0% by mass of an organic solvent with a boiling point of 210° C. to 280° C. in the ink. When such an ink is used, the affinity between organic solvent molecules can be reduced, and the permeability into the recording medium can be increased. In addition, it is considered that the organic solvent penetrates into the recording medium to compensate for the loss of moisture in the paper, thereby suppressing curling. Therefore, according to this embodiment, by using such a recording device and ink, a recording device that does not curl on thin paper and has excellent drying properties on thick paper can be provided.

[0019] The hot air device 5 is an example of a hot air blowing means, and blows hot air to the recording medium onto which ink has been ejected. In this embodiment, the ejection means, exhaust means, heating means, and hot air blowing means are arranged in this order from the upstream side in the conveying direction of the recording medium. By arranging in this manner, and in particular by arranging the hot air blowing means downstream of the heating means, it is possible to prevent the hot air from obstructing the air flow that causes steam generated by heating by the heating means to come into contact with the recording medium before it is heated.

[0020] The arrangement of the IR heater 4 and the exhaust duct 6 can be changed as appropriate. It is preferable that a path for transporting the recording medium before it reaches the IR heater 4 exists between the IR heater 4 and the suction port of the exhaust duct 6. In this case, the recording medium can be more reliably passed through the steam heated by the IR heater 4, and moisture can be easily absorbed by the recording medium. In addition, the phrase "between the IR heater 4 and the suction port of the exhaust duct 6" can also be referred to as being on a straight line connecting the IR heater 4 and the exhaust duct 6, and it is taken into consideration whether a transport path for the recording medium exists on such a straight line.

[0021] In this embodiment, whether or not an air flow is generated such that the steam generated by heating by the heating means comes into contact with the recording medium before it is heated can be determined, for example, as follows. For example, it can be determined by taking into consideration the relationship between the position where the heating means irradiates light and the position on the recording medium where the light is irradiated, the position of the suction port in the exhaust means that sucks in air, and the transport path of the recording medium. Alternatively, it can be actually measured using an anemometer such as the Anemomaster Light Model 6006-D0 manufactured by KANOMAX.

[0022] 2 is a diagram for explaining an example of the flow of air currents in the recording apparatus of this embodiment. Note that a description of the same matters as those described above will be omitted.

[0023] In this example, the IR heater 4 irradiates the recording medium with IR light 4a in the direction shown in the drawing. However, the direction and irradiation area of ​​the IR light 4a can be changed as appropriate and are not limited to this example.

[0024] The airflows generated when steam generated by heating with the IR heater 4 is sucked into the exhaust duct 6 are shown diagrammatically by arrows A1 to A3 (also referred to as airflows A1 to A3, etc.). Air sucked in from the suction port 6a of the exhaust duct 6 passes through the exhaust duct 6 and is exhausted (also referred to as exhaust) from the exhaust port 6b. An example of the flow of the exhausted air is diagrammatically shown by arrow B.

[0025] In this embodiment, for example, the air currents A1 and A3 are air currents that allow the vapor generated by heating to come into contact with the recording medium before it is heated. By generating such air currents, the above-mentioned effects can be obtained.

[0026] The dashed circle C in the figure roughly indicates an area where such a path exists between the IR heater 4 and the suction port of the exhaust duct 6, for the path along which the recording medium is transported before reaching the IR heater 4. The existence of such a path provides the above-mentioned effect.

[0027] The hot air device 5 in this embodiment blows hot air in the illustrated direction downstream of the IR heater 4 to dry the recording medium. By drying the recording medium in this manner, it is possible to prevent the hot air from blocking the airflow that brings the steam generated by heating into contact with the recording medium.

[0028] The recording device of the present invention may be used as a three-dimensional modeling device. The three-dimensional modeling device for modeling a three-dimensional object in the present invention may adopt a known configuration, and is not particularly limited, but may be, for example, one equipped with an ink storage means, a supply means, a discharge means, a drying means, etc. The three-dimensional object includes a three-dimensional object obtained by applying ink over and over. Also included is a molded product obtained by processing a structure to which ink is applied on a substrate such as a recording medium. The molded product is, for example, a recorded matter or structure formed in a sheet or film shape, which is molded by heat stretching, punching, etc., and is preferably used for applications in which the surface is molded after decoration, such as meters and operation panel of automobiles, office automation equipment, electric and electronic equipment, cameras, etc.

[0029] (ink) The organic solvent, water, coloring material, resin, additives, etc. used in the ink will be described below. The ink used in the present invention contains a coloring material, an organic solvent, and water, and may contain other components as required.

[0030] <Organic solvent> The organic solvent used in the present invention is not particularly limited, and any water-soluble organic solvent can be used. Examples of the organic solvent include polyhydric alcohols, ethers such as polyhydric alcohol alkyl ethers and polyhydric alcohol aryl ethers, nitrogen-containing heterocyclic compounds, amides, amines, and sulfur-containing compounds.

[0031] Specific examples of polyhydric alcohols include ethylene glycol, diethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 3-methyl-1,3-butanediol, triethylene glycol, polyethylene glycol, polypropylene glycol, 1,2-pentanediol, 1,3-pentanediol, and 1,4-pentanediol. Examples of such hexanediol include 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, and petriol. Examples of 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 polyhydric alcohol aryl ethers include ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether. Examples of the 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. Examples of the amides include formamide, N-methylformamide, N,N-dimethylformamide, 3-methoxy-N,N-dimethylpropionamide, and 3-butoxy-N,N-dimethylpropionamide. Examples of the amines include monoethanolamine, diethanolamine, and triethylamine. Examples of sulfur-containing compounds include dimethyl sulfoxide, sulfolane, and thiodiethanol. Other organic solvents include propylene carbonate, ethylene carbonate, and the like. It is preferable to use an organic solvent having a boiling point of 250° C. or less, since this not only functions as a wetting agent but also provides good drying properties.

[0032] As described above, in the present invention, the ink contains 3.0% to 15.0% by mass of an organic solvent having a boiling point of 210° C. to 280° C. This allows for good drying performance on thick paper and curl resistance on thin paper. If the organic solvent is less than 3.0% by mass, curl resistance on thin paper deteriorates, and if it exceeds 15.0% by mass, drying performance on thick paper deteriorates.

[0033] From the viewpoint of improving curl resistance on thin paper, the ink preferably contains an organic solvent having a boiling point of 240° C. or more and 280° C. or less in an amount of 3.0% by mass or more and 15.0% by mass or less.

[0034] In addition, from the viewpoint of improving curl resistance in thin paper, it is more preferable that the organic solvent contains diethanolamine. Although the reason is unclear, it is expected that diethanolamine has better permeability into the recording medium than other solvents, as it improves curl resistance. The diethanolamine content is preferably 10% by mass or more and 45% by mass or less of the total organic solvent.

[0035] <Water> The water content in the ink is not particularly limited and can be selected appropriately depending on the purpose. From the viewpoints of the drying property and ejection reliability of the ink, however, the water content is preferably from 10% by mass to 90% by mass, and more preferably from 20% by mass to 80% by mass.

[0036] <Coloring material> The coloring material is not particularly limited, and pigments and dyes can be used. As the pigment, an inorganic pigment or an organic pigment can be used. These pigments can be used alone or in combination of two or more. Also, mixed crystals can be used as the pigment. Examples of pigments that can be used include black pigments, yellow pigments, magenta pigments, cyan pigments, white pigments, green pigments, orange pigments, glossy pigments such as gold and silver pigments, and metallic pigments. As inorganic pigments, titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow, as well as carbon black produced by known methods such as the contact method, furnace method, and thermal method can be used. As organic pigments, azo pigments, polycyclic pigments (e.g., phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, etc.), dye chelates (e.g., basic dye chelates, acid dye chelates, etc.), nitro pigments, nitroso pigments, aniline black, etc. can be used. Among 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.

[0037] Specific examples of pigments for black colors include carbon blacks (CI Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black; metals such as copper, iron (CI Pigment Black 11), and titanium oxide; and organic pigments such as aniline black (CI Pigment Black 1). In addition, for color, CI 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, CI Pigment Yellow Range 5, 13, 16, 17, 36, 43, 51, CI 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 (red oxide), 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, CI Pigment Violet 1 (Rhodamine Lake), 3, 5:1, 16, 19, 23, 38; CI Pigment Blue 1, 2, 15 (Phthalocyanine Blue), 15:1, 15:2, 15:3, 15:4 (Phthalocyanine Blue), 16, 17:1, 56, 60, 63; CI Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc. The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, and basic dyes can be used. One type of dye may be used alone, or two or more types may be used in combination.

[0038] Dyes such as CI Acid Yellow 17, 23, 42, 44, 79, 142, CI Acid Red 52, 80, 82, 249, 254, 289, CI Acid Blue 9, 45, 249, CI Acid Black 1, 2, 24, 94, CI Food Black 1, 2, CI Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, 173, CI Direct Red 1, 4, 9, 80, 81, 225, 227, CI Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202, CI Directed Black 19, 38, 51, 71, 154, 168, 171, 195, CI Reactive Red 14, 32, 55, 79, 249, and CI Reactive Black 3, 4, and 35.

[0039] The content of the coloring material in the ink is preferably from 0.1% to 15% by mass, and more preferably from 1% to 10% by mass, from the viewpoints of improving image density, good fixing property and ejection stability.

[0040] Methods for dispersing a pigment to obtain an ink include a method in which a hydrophilic functional group is introduced into the pigment to make it a self-dispersing pigment, a method in which the surface of the pigment is coated with a resin and then dispersed, and a method in which a dispersant is used to disperse the pigment. As a method for introducing a hydrophilic functional group into a pigment to make it a self-dispersing pigment, for example, a method in which a functional group such as a sulfone group or a carboxyl group is added to a pigment (e.g., carbon) to make it dispersible in water can be mentioned. As a method for dispersing a pigment by coating its surface with a resin, there is a method in which the pigment is encapsulated in a microcapsule to make it dispersible in water. This can be called a resin-coated pigment. In this case, it is not necessary for all of the pigments blended in the ink to be coated with a resin, and uncoated or partially coated pigments may be dispersed in the ink as long as the effect of the present invention is not impaired.

[0041] Examples of the method for dispersing using a dispersant include a method for dispersing using a known low molecular weight dispersant or a polymeric dispersant, typified by a surfactant. As the dispersant, for example, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, etc. can be used depending on the pigment. As the dispersant, RT-100 (nonionic surfactant) manufactured by Takemoto Oil Co., Ltd. and sodium naphthalenesulfonate formalin condensate can also be suitably used. The dispersants may be used alone or in combination of two or more.

[0042] <Resin> The type of resin contained in the ink is not particularly limited and can be appropriately selected depending on the purpose. Examples of the resin include urethane resin, polyester resin, acrylic resin, vinyl acetate resin, styrene resin, butadiene resin, styrene-butadiene resin, vinyl chloride resin, acrylic styrene resin, and acrylic silicone resin. Resin particles made of these resins may be used. The resin particles may be dispersed in water as a dispersion medium to form a resin emulsion, and the resin particles may be mixed with materials such as coloring materials and organic solvents to obtain an ink. The resin particles may be appropriately synthesized or may be commercially available. These may be used alone or in combination of two or more types of resin particles.

[0043] The volume average particle size of the resin particles is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoint of obtaining good fixing property and high image hardness, however, it is preferably from 10 nm to 1,000 nm, more preferably from 10 nm to 200 nm, and particularly preferably from 10 nm to 100 nm.

[0044] The volume average particle size can be measured, for example, using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac-Bell Co., Ltd.). The resin content is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoints of fixation property and storage stability of the ink, however, the resin content is preferably from 1% by mass to 30% by mass, and more preferably from 5% by mass to 20% by mass, of the total amount of the ink.

[0045] The particle size of the solid content in the ink is not particularly limited and can be appropriately selected according to the purpose. In order to improve the image quality such as ejection stability and image density, the maximum frequency of the particle size of the solid content in the ink is preferably 20 nm or more and 1000 nm or less, more preferably 20 nm or more and 150 nm or less, in terms of the maximum number. The solid content includes resin particles, pigment particles, etc. The particle size can be measured using a particle size analyzer (Nanotrac Wave-UT151, manufactured by Microtrac Bell Co., Ltd.).

[0046] <Additives> If necessary, surfactants, antifoaming agents, antiseptics, antifungals, rust inhibitors, pH adjusters, etc. may be added to the ink.

[0047] <Surfactant> As the surfactant, any of silicone-based surfactants, fluorine-based surfactants, amphoteric surfactants, nonionic surfactants, and anionic surfactants can be used. The silicone surfactant is not particularly limited and can be appropriately selected according to the purpose. Among them, those that do not decompose even at high pH are preferable. Examples of silicone surfactants include side chain modified polydimethylsiloxane, both end modified polydimethylsiloxane, one end modified polydimethylsiloxane, and both end modified polydimethylsiloxane of side chain. Those having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as a modified group are particularly preferable because they show good properties as an aqueous surfactant. In addition, polyether modified silicone surfactants can also be used as silicone surfactants, and examples thereof include compounds in which a polyalkylene oxide structure is introduced into the Si part side chain of dimethylsiloxane.

[0048] As the fluorosurfactant, for example, perfluoroalkylsulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chain are particularly preferred because they have low foaming properties. As the perfluoroalkylsulfonic acid compounds, for example, perfluoroalkylsulfonic acid, perfluoroalkyl sulfonate, etc. are included. As the perfluoroalkyl carboxylic acid compounds, for example, perfluoroalkyl carboxylic acid, perfluoroalkyl carboxylate, etc. are included. As the polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in the side chain, sulfate ester salts of polyoxyalkylene ether polymers having perfluoroalkyl ether groups in the side chains, salts of polyoxyalkylene ether polymers having perfluoroalkyl ether groups in the side chains, etc. are included. As the counter ions of the salts in these fluorosurfactants, Li, Na, K, NH4, NH3CH2CH2OH, NH2(CH2CH2OH)2, NH(CH2CH2OH)3, etc. are included. Examples of amphoteric surfactants include lauryl aminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, and lauryl dihydroxyethyl betaine. Examples of nonionic surfactants include polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, polyoxyethylene alkylamines, polyoxyethylene alkylamides, polyoxyethylene propylene block polymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters, and ethylene oxide adducts of acetylene alcohol. Examples of the anionic surfactant include polyoxyethylene alkyl ether acetates, dodecylbenzene sulfonates, laurates, and polyoxyethylene alkyl ether sulfates. These may be used alone or in combination of two or more. The silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. Examples of the silicone surfactant include side-chain modified polydimethylsiloxane, both-end modified polydimethylsiloxane, one-end modified polydimethylsiloxane, and both-end side-chain modified polydimethylsiloxane. Polyether-modified silicone surfactants having a polyoxyethylene group or a polyoxyethylene polyoxypropylene group as the modifying group are particularly preferred because they exhibit good properties as an aqueous surfactant.

[0049] Such surfactants may be appropriately synthesized or commercially available products, such as those available from BYK-Chemie Co., Ltd., Shin-Etsu Chemical Co., Ltd., Dow Corning Toray Silicone Co., Ltd., Nippon Emulsion Co., Ltd., and Kyoeisha Chemical Co., Ltd. The polyether-modified silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. For example, it can be a surfactant represented by the general formula (S-1) in which a polyalkylene oxide structure is introduced into the Si part side chain of dimethylpolysiloxane.

[0050] [ka]

[0051] (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.)

[0052] As the polyether-modified silicone surfactant, commercially available products can be used, such as KF-618, KF-642, KF-643 (Shin-Etsu Chemical Co., Ltd.), EMALEX-SS-5602, SS-1906EX (Nihon Emulsion Co., Ltd.), FZ-2105, FZ-2118, FZ-2154, FZ-2161, FZ-2162, FZ-2163, FZ-2164 (Dow Corning Toray Silicone Co., Ltd.), BYK-33, BYK-387 (BYK-Chemie Co., Ltd.), TSF4440, TSF4452, TSF4453 (Toshiba Silicon Co., Ltd.), and the like. As the fluorine-based surfactant, a compound having 2 to 16 fluorine-substituted carbon atoms is preferable, and a compound having 4 to 16 fluorine-substituted carbon atoms is more preferable. Examples of fluorine-based surfactants include perfluoroalkyl phosphate compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in side chains, etc. Among these, polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups in side chains are preferred because they have low foaming properties, and fluorine-based surfactants represented by general formula (F-1) and general formula (F-2) are particularly preferred.

[0053] [ka]

[0054] In the compound represented by the above 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.

[0055] [ka]

[0056] In the compound represented by the above general formula (F-2), Y is H or C m F 2m+1 m is an integer from 1 to 6, or CH2CH(OH)CH2-Cm F 2m+1 m is an integer between 4 and 6, or C p H 2p+1 where p is an integer from 1 to 19. n is an integer from 1 to 6. a is an integer from 4 to 14.

[0057] As the fluorine-based surfactant, commercially available products may be used. Examples of such commercially available products 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.); Fullard FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, and FC-431 (all manufactured by Sumitomo 3M Limited); Megafa 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 (manufactured by OMNOVA Co., Ltd.), Unidyne DSN-403N (manufactured by Daikin Industries, Ltd.), and the like. Among these, FS-3100, FS-34, FS-300 manufactured by Chemours Co., Ltd., FT-110, FT-250, FT-251, FT-400S, FT-150, FT-400SW manufactured by NEOS Co., Ltd., Polyfox PF-151N manufactured by OMNOVA Co., Ltd., and Unidyne DSN-403N manufactured by Daikin Industries, Ltd. are particularly preferred from the viewpoint of excellent print quality, particularly color development, penetration into paper, wettability, and uniform dyeing.

[0058] The content of the surfactant in the ink is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoints of excellent wettability and ejection stability and improved image quality, the content is preferably from 0.001% by mass to 5% by mass, and more preferably from 0.05% by mass to 5% by mass.

[0059] <Defoaming agent> There are no particular restrictions on the defoaming agent, and examples thereof include silicone-based defoaming agents, polyether-based defoaming agents, fatty acid ester-based defoaming agents, etc. These may be used alone or in combination of two or more. Among these, silicone-based defoaming agents are preferred because of their excellent defoaming effect.

[0060] <Antiseptic and antifungal agent> There are no particular restrictions on the antiseptic and antifungal agent, and examples thereof include 1,2-benzisothiazolin-3-one, etc.

[0061] <Rust inhibitor> There are no particular restrictions on the rust inhibitor, and examples thereof include acid sulfite, sodium thiosulfate, etc.

[0062] <pH adjuster> There are no particular restrictions on the pH adjuster as long as it can adjust the pH to 7 or higher, and examples thereof include amines such as diethanolamine and triethanolamine. There are no particular restrictions on the physical properties of the ink, and they can be appropriately selected according to the purpose. For example, it is preferable that the viscosity, surface tension, pH, etc. are in the following ranges.

[0063] <Physical properties of ink> The viscosity of the ink at 25°C is preferably 3 mPa·s or more and 30 mPa·s or less, more preferably 5 mPa·s or more and 25 mPa·s or less, from the viewpoints of improving the printing density and character quality and obtaining good ejection properties. Here, for example, a rotational viscometer (RE-80L manufactured by Toki Sangyo Co., Ltd.) can be used to measure the viscosity. As the measurement conditions, it can be measured at 25°C, with a standard cone rotor (1°34’×R24), a sample liquid volume of 1.2 mL, a rotation speed of 50 rpm, and for 3 minutes. The surface tension of the ink is preferably 35 mN / m or less, more preferably 32 mN / m or less at 25°C, from the viewpoints of the ink being preferably leveled on the recording medium and shortening the drying time of the ink. The pH of the ink is preferably from 7 to 12, and more preferably from 8 to 11, from the viewpoint of preventing corrosion of metal members that come into contact with the ink.

[0064] <Recording Media> There are no particular limitations on the recording medium, and any hygroscopic material such as plain paper, glossy paper, special paper, or cloth can be used. The recording medium is not limited to those generally used as recording media, and may be wallpaper, flooring, building materials such as tiles, cloth for clothing such as T-shirts, textiles, leather, etc. By adjusting the configuration of the path for conveying the recording medium, ceramics, glass, metal, etc. may also be used. In addition, cut paper can be freely selected in addition to continuous paper.

[0065] The distinction between thin paper and thick paper can be made as appropriate, for example, by basis weight (gsm).

[0066] <Recordings> The ink recorded matter of the present invention comprises an image formed on a recording medium using the ink of the present invention. A recorded matter can be obtained by recording using an inkjet recording apparatus and an inkjet recording method.

[0067] <How to use ink> The ink can be used in a wide variety of ways, including, but not limited to, inkjet recording, blade coating, gravure coating, bar coating, roll coating, dip coating, curtain coating, slide coating, die coating, and spray coating. The application of the ink of the present invention is not particularly limited and can be appropriately selected depending on the purpose, and can be applied to, for example, printed matter, paint, coating material, undercoat, etc. Furthermore, the ink can be used not only to form two-dimensional characters and images when used as an ink, but also as a material for three-dimensional modeling to form three-dimensional solid images (three-dimensional objects).

[0068] In the present invention, the terms image formation, recording, printing, printing, etc. are all synonymous. Recording medium, media, and printed material are all synonymous. EXAMPLES

[0069] The present invention will be described in more detail below by way of examples, but the present invention is not limited to these examples.

[0070] (Examples 1 to 63, Comparative Examples 1 to 25) <Preparation of pigment dispersion> As the pigment dispersion, the following commercially available products were used. CAB-O-JET 400 (manufactured by Cabot) CAB-O-JET 450C (manufactured by Cabot) · CAB-O-JET 465M (manufactured by Cabot) · CAB-O-JET 480M (Cabot) · CAB-O-JET 470Y (manufactured by Cabot)

[0071] <Preparation of resin emulsion> As the resin emulsion, the following commercially available products were used. Takelac W5661 (Mitsui Chemicals) Neocryl BT-9 (DSM Coating Resins) Lube190 (MICHELMAN)

[0072] <Preparation of organic solvent> As the organic solvent, the following commercially available products were used. Glycerin (Tokyo Chemical Industry Co., Ltd., boiling point 290℃) Trimethylolpropane (Tokyo Chemical Industry Co., Ltd., boiling point 287°C) Triethylene glycol (Tokyo Chemical Industry Co., Ltd., boiling point 287°C) N-Butyldiethanolamine (Tokyo Chemical Industry Co., Ltd., boiling point 275°C) 3-Methyl-1,5-pentanediol (Tokyo Chemical Industry Co., Ltd., boiling point 250°C) Diethylene glycol (Tokyo Chemical Industry Co., Ltd., boiling point 240°C) 3-Ethyl-3-hydroxymethyloxetane (Tokyo Chemical Industry Co., Ltd., boiling point 227°C) 1,2-Hexanediol (Tokyo Chemical Industry Co., Ltd., boiling point 223°C) 1,3-Propanediol (Tokyo Chemical Industry Co., Ltd., boiling point 214°C)

[0073] <Preparation of surfactant> As the surfactant, the following commercially available products were used. SAG-503A (manufactured by Nissin Chemical Industry Co., Ltd.) FS-300 (DuPont) Olefin E1004 (manufactured by Nissin Chemical Industry Co., Ltd.) Olefin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.)

[0074] <Preparation of preservatives> The following commercially available preservatives were used. Proxel LV (manufactured by Lonza Japan)

[0075] <Preparing the recording medium> The following commercially available products were used: Snowbrite (Town Rivers, 40gsm) ·NPi Form NEXT-IJ 70 (Made by Nippon Paper Industries, basis weight 81.4gsm) ·NPi Form NEXT-IJ 135 (Nippon Paper, basis weight 157gsm) Crown Letsgo Silk (Crown van Gelder, 250gsm)

[0076] <Ink preparation example> Each ink was prepared by mixing and stirring each material based on the ink recipe shown in Tables 1 to 11 below, filtering through a filter with an average pore size of 5 μm (Minisart, manufactured by Sartorius), and filtering through a 0.5 μm polypropylene filter. The numerical values ​​of each material in Tables 1 to 11 are in "mass %." The numerical values ​​showing the content of the pigment dispersion and resin in Tables 1 to 11 all represent the solid content. "COJ" stands for "CAB-O-JET."

[0077] (evaluation) Next, in each of the Examples and Comparative Examples, the drying property and curl resistance were evaluated based on the following methods. The evaluation results are shown in Tables 1 to 11 below.

[0078] <Drying> The ink thus prepared was used to form a solid image at a resolution of 600 dpi x 600 dpi using the device shown in Figure 1. Within 2 minutes of printing, the solid image was rubbed 20 times with a blank portion of a recording medium cut into a square of 1.2 cm, and the ink transfer stain onto the blank portion of the coated paper was measured using a reflective color spectrophotometric densitometer (manufactured by X-Rite). The transfer density was calculated by subtracting the background color of the rubbed white paper, and the drying property was evaluated based on the following evaluation criteria. AA and A are acceptable ranges.

[0079] [Evaluation Criteria] AA: Transfer density is less than 0.01 A: Transfer density is 0.01 or more and less than 0.03 B: Transfer density is 0.03 or more and less than 0.10 C: Transfer density is 0.10 or more

[0080] <Curl resistance> The ink was used to form a solid image at a resolution of 600 dpi x 600 dpi using the device shown in Figure 1. Within 2 minutes of printing, the media was cut into A4 size and placed face down on a flat surface. The height of the four corners of the recording media from the flat surface was measured and the result was evaluated according to the following criteria. AA and A are within the acceptable range.

[0081] [Evaluation Criteria] AA: Less than 5mm A: 5mm or more and less than 10mm B: 10mm or more and less than 20mm C:20mm or more

[0082] [Table 1]

[0083] [Table 2]

[0084] [Table 3]

[0085] [Table 4]

[0086] [Table 5]

[0087] [Table 6]

[0088] [Table 7]

[0089] [Table 8]

[0090] [Table 9]

[0091] [Table 10]

[0092] [Table 11]

[0093] Examples 1 to 63 show that when the ink contains 3.0% by mass or more and 15.0% by mass or less of an organic solvent having a boiling point of 210° C. or more and 280° C. or less, both curl resistance on thin paper and drying speed on thick paper are achieved. Furthermore, by comparing Examples 1 to 30, 34 to 36, and 40 to 51 with Examples 31 to 33, 37 to 39, and 52 to 63, it can be seen that the curl resistance of thin paper is improved when the ink contains 3.0% by mass or more and 15.0% by mass or less of an organic solvent having a boiling point of 240°C or more and 280°C or less. A comparison of Example 1 with Examples 29 and 30 shows that curl resistance is improved when the organic solvent contains diethanolamine. A comparison of Example 1 with Comparative Examples 1 to 25 reveals that unless the ink contains 3.0% by mass or more and 15.0% by mass or less of an organic solvent having a boiling point of 210°C or more and 280°C or less, the drying performance of thick paper and the curl resistance of thin paper cannot be achieved at the same time. [Explanation of symbols]

[0094] 1 Paper feeder 2 Winding device 3 Inkjet head 4. IR Heater 5. Hot air device 6 Exhaust duct P Continuous paper [Prior art documents] [Patent documents]

[0095] [Patent Document 1] JP 2014-205769 A [Patent Document 2] JP 2019-162796 A

Claims

1. an ink containing a coloring material, an organic solvent, and water, the ink containing an organic solvent having a boiling point of 210° C. or more and 280° C. or less in an amount of 3.0% by mass or more and 15.0% by mass or less; a discharge means for discharging the ink onto a recording medium; A conveying means for conveying the recording medium; a heating unit that irradiates light onto the recording medium on which the ink has been applied to heat the recording medium; and an exhaust means for exhausting air from within the housing, A recording apparatus characterized in that, when the steam generated by heating by the heating means is exhausted from the exhaust means, an air current is generated such that the heated steam comes into contact with the recording medium before it is heated.

2. 2. The recording apparatus according to claim 1, wherein the ink contains an organic solvent having a boiling point of 240° C. or more and 280° C. or less in an amount of 3.0% by mass or more and 15.0% by mass or less in the ink.

3. 3. The recording apparatus according to claim 1, wherein the organic solvent contains diethanolamine.

4. The exhaust means has a suction port for sucking air from inside the housing, 4. The recording apparatus according to claim 1, wherein a path for conveying the recording medium before it reaches the heating means is provided between the heating means and the suction port.

5. A hot air blowing means for blowing hot air onto the recording medium, 5. The recording apparatus according to claim 1, wherein the ejection means, the exhaust means, the heating means, and the hot air blowing means are arranged in this order from the upstream side in a transport direction of the recording medium.

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