Processing liquid and recording method

Abstract

To provide a treatment liquid capable of improving the abrasion resistance and the image quality of an image formed by an ink jet ink composition to be used in combination therewith, while favorably maintaining member reliability.SOLUTION: A treatment liquid is a water-based treatment liquid and is used for a recording method of adhering a water-based ink jet ink composition containing a colorant and the treatment liquid to a recording medium. The treatment liquid contains: an organic acid; and at least one selected from an organic acid polyvalent metal salt and a cationic polymer, wherein the content of the at least one selected from the organic acid polyvalent metal salt and the cationic polymer is 1 mass% or more and 15 mass% or less based on the total mass of the treatment liquid, and the treatment liquid has a pH of 5.5 or more.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a treatment liquid and a recording method. [Background technology]

[0002]

[0003] The inkjet method is capable of forming high-quality images on a recording medium, and thus various technical developments have been made in the past. For example, not only the development of recording devices using the inkjet method but also the development of compositions to be used in such devices has been active. Furthermore, attempts have been made to solve various problems in the combination of recording devices, inkjet ink compositions, treatment liquids, recording media, etc.

[0003] For example, as disclosed in Patent Document 1, a recording method is known in which a treatment liquid containing a flocculant that aggregates ink components is used to quickly fix (reduce fluidity) the ink that has adhered to the recording medium, thereby suppressing uneven bleeding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-091142 Summary of the Invention [Problem to be solved by the invention]

[0005] When a treatment liquid is used, there has been a lack of a treatment liquid that can improve the abrasion resistance and image quality of an image formed by an inkjet ink composition used in combination with the treatment liquid while maintaining good component reliability of the component for using the treatment liquid. [Means for solving the problem]

[0006] One aspect of the treatment liquid according to the present invention is An aqueous treatment liquid, The treatment liquid is used in a recording method in which a water-based ink-jet ink composition containing a coloring material and the treatment liquid are applied to a recording medium, Organic acids and and one or more selected from organic acid polyvalent metal salts and cationic polymers, the content of one or more selected from the organic acid polyvalent metal salt and the cationic polymer is 1% by mass or more and 15% by mass or less relative to the total mass of the treatment liquid, The pH is 5.5 or higher.

[0007] One aspect of the recording method according to the present invention is to a treatment liquid application step of applying the treatment liquid to the recording medium; an ink deposition step of depositing the inkjet ink composition onto the recording medium by an inkjet method; Equipped with. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of an example of an inkjet recording apparatus. [Figure 2] FIG. 1 is a schematic diagram of the periphery of a carriage in an example of an inkjet recording apparatus. DETAILED DESCRIPTION OF THE INVENTION

[0009] The following describes embodiments of the present invention. The embodiments described below are examples of the present invention. The present invention is not limited to the following embodiments, and includes various modified forms that are implemented within the scope of the present invention. Note that not all of the configurations described below are necessarily essential configurations of the present invention.

[0010] In this specification, "(meth)acrylic" refers to acrylic or methacrylic, and "(meth)acrylate" refers to acrylate or methacrylate.

[0011] 1. Processing solution The treatment liquid of this embodiment is an aqueous treatment liquid used in a recording method in which a water-based inkjet ink composition containing a colorant and the treatment liquid are applied to a recording medium. The treatment liquid contains an organic acid and one or more selected from an organic acid polyvalent metal salt and a cationic polymer. The content of the one or more selected from the organic acid polyvalent metal salt and the cationic polymer is 1% by mass or more and 15% by mass or less relative to the total mass of the treatment liquid, and the pH is 5.5 or higher.

[0012] Conventionally, when using a processing solution, polyvalent metal salts of inorganic acids have been used as flocculants because they have particularly excellent reactivity. However, many polyvalent metal salts of inorganic acids are deliquescent. As a result, the solvent components are difficult to evaporate during the secondary heating process and are prone to moisture absorption after recording, resulting in poor abrasion resistance of the image. Therefore, attempts have been made to use polyvalent metal salts of organic acids or cationic polymers, which do not significantly impair reactivity and have little deliquescent property. However, these have the disadvantage of being less reactive than polyvalent metal salts of inorganic acids, and the resulting image quality may be insufficient. Furthermore, while acids can function as flocculants, there have been concerns about the effects of the acid on components such as containers.

[0013] 1.1. Water-based treatment liquid The treatment liquid used in the recording method according to this embodiment is an aqueous treatment liquid containing water. "Aqueous" means that it contains water as one of the main solvent components. Water may be included as a main solvent component, and is a component that evaporates upon drying. The water is preferably pure water or ultrapure water, such as ion-exchanged water, ultrafiltered water, reverse osmosis water, or distilled water, from which ionic impurities have been removed as much as possible. Furthermore, using water sterilized by ultraviolet irradiation or the addition of hydrogen peroxide is preferable, as this can prevent the growth of mold and bacteria when the treatment liquid is stored for a long period of time.

[0014] The water content in the treatment liquid is preferably 40% by mass or more, more preferably 45% by mass or more, even more preferably 50% by mass or more, particularly preferably 55% by mass or more, more particularly preferably 60% by mass or more, and especially preferably 65% ​​by mass or more, relative to the total mass of the treatment liquid. There is no particular upper limit for the water content, but it is preferably 90% by mass or less, more preferably 80% by mass or less, relative to the total mass of the treatment liquid.

[0015] 1.2.Organic acids The treatment liquid contains an organic acid. The organic acid has the effect of aggregating the components of the inkjet ink composition. Compared to inorganic acid metal salts, organic acids are advantageous in drying because they do not have deliquescent properties, and they are also less likely to absorb moisture, so they can improve the abrasion resistance of images formed with the inkjet ink composition. Furthermore, by using an organic acid in combination with an organic acid polyvalent metal salt and / or a cationic polymer, the treatment liquid can exhibit excellent aggregating performance and can also improve the quality of images formed with the inkjet ink composition.

[0016] Organic acids can function as aggregating agents, but they also lower the pH of the treatment liquid. Therefore, if the organic acid content is too high, the pH of the treatment liquid will be too low, potentially deteriorating the materials of the container containing the treatment liquid (e.g., resins (epoxy resins, etc.), metals, etc.) and the materials of the recording medium to which the treatment liquid is applied. In other words, treatment liquids primarily containing organic acids have sometimes exhibited poor component reliability. Furthermore, if the pH of the treatment liquid is too low, the abrasion resistance of the recorded material tends to be poor, particularly in wet abrasion resistance. Furthermore, even after drying, if the pH of the treatment liquid is too low and moisture is added, the acid may cause deterioration of components such as resins contained in the recording medium and ink coating.

[0017] However, in the treatment liquid of this embodiment, by using a small amount of organic acid in combination with an organic acid polyvalent metal salt and / or a cationic polymer, it is possible to improve the abrasion resistance and image quality of images formed with the inkjet ink composition and maintain high component reliability. The treatment liquid may be applied to the recording medium by spraying, coating, etc., or by an inkjet method. In either case, the treatment liquid of this embodiment can increase component reliability.

[0018] Examples of organic acids include poly(meth)acrylic acid, formic acid, acetic acid, propionic acid, glycolic acid, oxalic acid, malonic acid, malic acid, maleic acid, ascorbic acid, succinic acid, glutaric acid, adipic acid, fumaric acid, citric acid, tartaric acid, lactic acid, pyruvic acid, pyrrolidonecarboxylic acid, pyrronecarboxylic acid, pyrrolecarboxylic acid, furancarboxylic acid, pyridinecarboxylic acid, coumaric acid, thiophenecarboxylic acid, nicotinic acid, and derivatives of these compounds. The organic acid may be a monovalent acid or a divalent or higher acid. The organic acid may also be a hydroxy acid having a hydroxyl group, such as lactic acid. Furthermore, aliphatic divalent organic acids such as adipic acid and succinic acid are more preferred because they have reduced odor and good solubility in water. One organic acid may be used alone, or two or more organic acids may be used in combination.

[0019] The total content of the organic acid relative to the total mass of the treatment solution is preferably 0.0001% by mass or more and 5.0% by mass or less. It is further preferably 0.001% by mass or more and 3.0% by mass or less, more preferably 0.002% by mass or more and 2.5% by mass or less, and even more preferably 0.003% by mass or more and 2.4% by mass or less. From the viewpoint of component reliability, the upper limit of the organic acid content is preferably 2.5% by mass or less, more preferably 1.0% by mass or less, even more preferably 0.3% by mass or less, and most preferably 0.3% by mass or less.

[0020] 1.3. Organic acid polyvalent metal salts The treatment liquid contains at least one selected from the group consisting of organic acid polyvalent metal salts and cationic polymers. In this section, the organic acid polyvalent metal salts will be described.

[0021] An organic acid polyvalent metal salt refers to a salt formed by combining an organic acid with a polyvalent metal. The organic acid polyvalent metal salt is composed of an organic acid anion and a polyvalent metal cation. Examples of such organic acids include any of the organic acids described above. Examples of polyvalent metals include divalent or higher metals, such as calcium, magnesium, copper, nickel, zinc, barium, aluminum, titanium, strontium, chromium, cobalt, and iron.

[0022] As the organic acid of the organic acid polyvalent metal salt, aliphatic monovalent organic acids such as formic acid, acetic acid, propionic acid, and lactic acid are preferred because they have a higher aggregating ability for the components of the inkjet ink composition. On the other hand, as the polyvalent metal of the organic acid polyvalent metal salt, calcium or magnesium is preferred because they have an excellent aggregating ability for the components of the inkjet ink. When the organic acid polyvalent metal salt is a magnesium salt or a calcium salt, the stability of the treatment liquid tends to be better.

[0023] The organic acid polyvalent metal salt functions as an aggregating agent that aggregates the components of the inkjet ink composition. In the treatment liquid, the organic acid described above and the organic acid of the organic acid polyvalent metal salt described above are preferably different in type, as this provides better image quality and the like.

[0024] Furthermore, in the treatment liquid, when the organic acid is a divalent organic acid and the organic acid polyvalent metal salt is a salt formed from a monovalent organic acid and a polyvalent metal, the drying properties are improved, and the abrasion resistance of the image formed from the inkjet ink composition can be improved.

[0025] The organic acid polyvalent metal salts may be used alone or in combination of two or more. When the treatment liquid contains an organic acid polyvalent metal salt, the content of the organic acid polyvalent metal salt is preferably 0.5 to 15.0 mass% in total relative to the total mass of the treatment liquid. More preferably, it is 1.0 mass% or more and 10.0 mass% or less, preferably 2.0 mass% or more and 9.0 mass% or less, more preferably 3.0 mass% or more and 8.0 mass% or less, and even more preferably 3.0 mass% or more and 5.0 mass% or less.

[0026] 1.4.Cationic Polymers The treatment liquid contains one or more members selected from the group consisting of organic acid polyvalent metal salts and cationic polymers. In this section, the cationic polymers will be described.

[0027] The cationic polymer refers to a polymer compound having a cationic group. Examples of the cationic polymer include cationic urethane resins, cationic olefin resins, and cationic amine resins. The cationic polymer functions as a flocculant that aggregates the components of the inkjet ink composition.

[0028] As the cationic urethane-based resin, commercially available products can be used, such as Hydran CP-7010, CP-7020, CP-7030, CP-7040, CP-7050, CP-7060, and CP-7610 (trade names, manufactured by Dainippon Ink and Chemicals, Inc.), Superflex 600, 610, 620, 630, 640, and 650 (trade names, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and Urethane Emulsion WBR-2120C and WBR-2122C (trade names, manufactured by Taisei Fine Chemical Co., Ltd.).

[0029] The cationic olefin resin has an olefin such as ethylene or propylene in its structural skeleton, and known resins can be appropriately selected and used. The cationic olefin resin may also be in an emulsion state dispersed in a solvent containing water or an organic solvent. Commercially available cationic olefin resins can be used, such as Arrowbase CB-1200 and CD-1200 (trade names, manufactured by Unitika Ltd.).

[0030] The cationic amine resin (cationic polymer) may be any resin having an amino group in its structure, and known resins may be appropriately selected and used. Examples include polyamine resins, polyamide resins, and polyallylamine resins. Polyamine resins are resins having amino groups in their main skeletons. Polyamide resins are resins having amide groups in their main skeletons. Polyallylamine resins are resins having a structure derived from allyl groups in their main skeletons.

[0031] Examples of cationic polyamine resins include Unisense KHE103L (hexamethylenediamine / epichlorohydrin resin, 1% aqueous solution with a pH of approximately 5.0, a viscosity of 20 to 50 (mPa·s), and a solids concentration of 50% by mass) and Unisense KHE104L (dimethylamine / epichlorohydrin resin, 1% aqueous solution with a pH of approximately 7.0, a viscosity of 1 to 10 (mPa·s), and a solids concentration of 20% by mass), both manufactured by Senka Corporation. Specific examples of commercially available cationic polyamine resins include FL-14 (manufactured by SNF Co., Ltd.), Arafix 100, 251S, 255, and 255LOX (manufactured by Arakawa Chemical Co., Ltd.), DK-6810, 6853, and 6885; WS-4010, 4011, 4020, 4024, 4027, and 4030 (manufactured by Seiko PMC Co., Ltd.), Papiogen P-105 (manufactured by Senka Co., Ltd.), and Sumire. Examples of such resins include: Zeus Resin 650(30), 675A, 6615, and SLX-1 (manufactured by Taoka Chemical Co., Ltd.); Catiomaster (registered trademark) PD-1, PD-7, PD-30, PD-A, PDT-2, PE-10, PE-30, DT-EH, EPA-SK01, and TMHMDA-E (manufactured by Yokkaichi Synthetic Co., Ltd.); and Jetfix 36N, 38A, and 5052 (manufactured by Satoda Chemical Co., Ltd.).

[0032] Examples of polyallylamine resins include polyallylamine hydrochloride, polyallylamine amidosulfate, allylamine hydrochloride-diallylamine hydrochloride copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine hydrochloride-dimethylallylamine hydrochloride copolymer, allylamine-dimethylallylamine copolymer, polydiallylamine hydrochloride, polymethyldiallylamine hydrochloride, polymethyldiallylamine amidosulfate, polymethyldiallylamine acetate, polydiallyldimethylammonium chloride, diallylamine acetate-sulfur dioxide copolymer, diallylmethylethylammonium ethyl sulfate-sulfur dioxide copolymer, methyldiallylamine hydrochloride-sulfur dioxide copolymer, diallyldimethylammonium chloride-sulfur dioxide copolymer, and diallyldimethylammonium chloride-acrylamide copolymer.

[0033] The cationic polymer may be used alone or in combination of two or more. When the cationic polymer is contained in the treatment liquid, the content of the cationic polymer is preferably 0.1 to 15.0 mass% in total relative to the total mass of the treatment liquid. More preferably, it is 0.1 to 8.0 mass%, more preferably 0.5 to 5.0 mass%, even more preferably 1.0 to 4.0 mass%, and even more preferably 1.0 to 3.0 mass%.

[0034] 1.5. Content of one or more selected from organic acid polyvalent metal salts and cationic polymers The total content of one or more selected from organic acid polyvalent metal salts and cationic polymers in the treatment liquid is, relative to the total mass of the treatment liquid, from 1.0 to 15.0% by mass, and more preferably, for example, from 1.0 to 10.0% by mass, preferably from 2.0 to 9.0% by mass, more preferably from 3.0 to 8.0% by mass, and even more preferably from 3.0 to 5.0% by mass. If these contents are within the above ranges, the components of the inkjet ink composition can be sufficiently cohesive by the treatment liquid.

[0035] 1.6.Other Ingredients 1.6.1.Water-soluble low molecular weight compounds The treatment liquid may contain a water-soluble low-molecular-weight compound. By including a water-soluble low-molecular-weight organic compound, the drying properties of an image formed using the inkjet ink composition can be further improved. Examples of water-soluble low-molecular-weight organic compounds include, but are not limited to, alcohols, alkanediols, alkanepolyols, alkylene glycol ethers, esters, amides, sulfur-containing solvents, and cyclic ethers.

[0036] The term "water-soluble" in the context of a water-soluble low-molecular-weight organic compound refers to a solubility of more than 10 g in 100 g of water at 20°C. Furthermore, the term "low molecular weight" refers to a molecular weight of 300 or less, more preferably 30 or more and 250 or less, even more preferably 50 or more and 200 or less, and particularly preferably 70 or more and 150 or less. The water-soluble low-molecular-weight organic solvent may be, but is not limited to, a water-soluble organic solvent.

[0037] Examples of alcohols include compounds in which one hydrogen atom of an alkane has been substituted with a hydroxyl group. The alkane preferably has 10 or less carbon atoms, more preferably 6 or less, and even more preferably 3 or less. The alkane has 1 or more carbon atoms, preferably 2 or more. The alkane may be linear or branched. Examples of alcohols include methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butanol, 2-butanol, tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol.

[0038] Examples of alkanediols include compounds in which an alkane is substituted with two hydroxyl groups. Examples of alkanediols include ethylene glycol (also known as ethane-1,2-diol), propylene glycol (also known as propane-1,2-diol), 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, 1,3-propanediol, 1,3-butylene glycol (also known as 1,3-butanediol), 1,4-butanediol, 2,3-butanediol, 1,2-pentanediol, 1,5-pentanediol, 2,4-pentanediol, 2-methyl-1,3-propanediol, and 3-methyl-1,3 1,6-hexanediol, 2-ethyl-2-methyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, neopentyl glycol (also known as 2,2-dimethyl-1,3-propanediol), pinacol (also known as 2,3-dimethyl-2,3-butanediol), and the like.

[0039] Examples of alkane polyols include alkane diols, condensates in which two or more molecules of alkane diols are intermolecularly condensed via the hydroxyl groups thereof, alkanes having three or more hydroxyl groups, etc. The above-mentioned alkane diols are also included in the alkane polyols.

[0040] Examples of condensates in which two or more molecules of alkanediols are intermolecularly condensed via the hydroxyl groups thereof include dialkylene glycols such as diethylene glycol and dipropylene glycol, and trialkylene glycols such as triethylene glycol and tripropylene glycol.

[0041] Alkanes with three or more hydroxyl groups are compounds with three or more hydroxyl groups and have a skeleton of an alkane or a polyol with a polyether structure, etc. Examples include alkanes or polyols with a polyether structure substituted with three or more hydroxyl groups.

[0042] Examples of alkanes having three or more hydroxyl groups include glycerin, trimethylolethane, trimethylolpropane, 1,2,5-hexanetriol, 1,2,6-hexanetriol, pentaerythritol, and polyoxypropylenetriol.

[0043] Examples of alkylene glycol ethers include those in which one or more hydroxyl groups of the above-mentioned alkane polyols have been etherified. Examples include alkylene glycol monoethers in which one hydroxyl group has been etherified, and alkylene glycol diethers in which two hydroxyl groups have been etherified. Alkylene glycol monoethers are more preferred.

[0044] Examples of etherification include alkyl ethers and aryl ethers, with alkyl ethers being preferred. The number of carbon atoms in the ether moiety of the etherification is preferably 1 to 8, and more preferably 1 to 4. The number of carbon atoms in the alkylene glycol moiety of alkylene glycol ethers is preferably 2 to 6. The number of repeating alkylene glycol moieties is preferably 1 to 5.

[0045] Examples of alkylene glycol ethers include alkylene glycol monoethers and alkylene glycol diethers, with alkylene glycol monoethers being more preferred. Specific examples include 2-methoxyethanol (also known as ethylene glycol monomethyl ether), 2-ethoxyethanol (also known as ethylene glycol monoethyl ether), ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, tetraethylene glycol monoethyl ether, tetraethylene glycol monobutyl ether, 1-methoxy-2-propanol (also known as propylene glycol 1-monomethyl ether), 2-methoxypropanol (also known as propylene glycol 2-monomethyl ether), 1-ethoxy-2-propyl alkylene glycol monoethers such as propanol (also known as propylene glycol monoethyl ether), propylene glycol monopropyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monobutyl ether, tripropylene glycol monobutyl ether, 3-methoxy-1-propanol (also known as 1,3-propanediol monomethyl ether), 1-methoxy-2-butanol (also known as 1,2-butanediol 1-monomethyl ether), 2-methoxy-1-butanol, 3-methoxy-1-butanol (also known as 1,3-butanediol 3-monomethyl ether), 4-methoxy-1-butanol (also known as 1,4-butanediol monomethyl ether), and 3-methoxy-3-methyl-1-butanol; and Examples of alkylene glycol diethers include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, diethylene glycol methyl ethyl ether, diethylene glycol methyl butyl ether, triethylene glycol dimethyl ether, triethylene glycol diethyl ether, triethylene glycol dibutyl ether, triethylene glycol methyl butyl ether, tetraethylene glycol dimethyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dibutyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol dimethyl ether.

[0046] Examples of the esters include acyclic esters and cyclic esters.

[0047] Examples of the acyclic esters include glycol monoacetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and methoxybutyl acetate; Examples of glycol diesters include ethylene glycol diacetate, diethylene glycol diacetate, propylene glycol diacetate, dipropylene glycol diacetate, ethylene glycol acetate propionate, ethylene glycol acetate butyrate, diethylene glycol acetate butyrate, diethylene glycol acetate propionate, diethylene glycol acetate butyrate, propylene glycol acetate propionate, propylene glycol acetate butyrate, dipropylene glycol acetate butyrate, and dipropylene glycol acetate propionate.

[0048] Examples of cyclic esters include cyclic esters (lactones) such as β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, β-butyrolactone, β-valerolactone, γ-valerolactone, β-hexanolactone, γ-hexanolactone, δ-hexanolactone, β-heptanolactone, γ-heptanolactone, δ-heptanolactone, ε-heptanolactone, γ-octanolactone, δ-octanolactone, ε-octanolactone, δ-nonalactone, ε-nonalactone, and ε-decanolactone, and compounds in which the hydrogen atom of the methylene group adjacent to the carbonyl group of these cyclic esters is substituted with an alkyl group having 1 to 4 carbon atoms.

[0049] Examples of the amides include cyclic amides and non-cyclic amides. Examples of the non-cyclic amides include alkoxyalkyl amides.

[0050] Examples of cyclic amides include lactams, such as pyrrolidones such as 2-pyrrolidone (normal boiling point 245° C.), 1-methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1-propyl-2-pyrrolidone, and 1-butyl-2-pyrrolidone, 2-piperidone, ε-caprolactam, N-methyl-ε-caprolactam, N-cyclohexyl-2-pyrrolidone, 5-methyl-2-pyrrolidone, β-propiolactam, ω-heptalactam, and succinimide. Among these, 2-pyrrolidone and ε-caprolactam are particularly preferred.

[0051] Examples of the acyclic amides include 3-methoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, 3-methoxy-N,N-methylethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-diethylpropionamide, 3-ethoxy-N,N-methylethylpropionamide, 3-n-butoxy-N,N-dimethylpropionamide, 3-n-butoxy-N,N-diethylpropionamide, 3-n-butoxy-N,N-methylethylpropionamide, 3-n-propoxy-N,N-dimethylpropionamide, 3-n-propoxy-N,N-diethylpropionamide, 3-n-propoxy-N,N-methylethylpropionamide, 3-iso-propoxy- Examples include alkoxyalkylamides such as N,N-dimethylpropionamide, 3-iso-propoxy-N,N-diethylpropionamide, 3-iso-propoxy-N,N-methylethylpropionamide, 3-tert-butoxy-N,N-dimethylpropionamide, 3-tert-butoxy-N,N-diethylpropionamide, and 3-tert-butoxy-N,N-methylethylpropionamide; N,N-dimethylacetoacetamide, N,N-diethylacetoacetamide, N-methylacetoacetamide, N,N-dimethylisobutyric acid amide, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, and N,N-dimethylpropionamide.

[0052] Examples of sulfur-containing solvents include sulfoxides and sulfones. Examples of sulfoxides include acyclic sulfoxides such as dimethyl sulfoxide and diethyl sulfoxide, and cyclic sulfoxides such as tetramethylene sulfoxide. Examples of sulfones include cyclic sulfones such as 3-methyl sulfolane and sulfolane, and acyclic sulfones such as ethyl isopropyl sulfone, ethyl methyl sulfone, and dimethyl sulfone.

[0053] Examples of cyclic ethers include tetrahydrofuran, 1,4-dioxane, dimethylisosorbide, 3-methyl-3-oxetanemethanol, 3-ethyl-3-oxetanemethanol, 2-hydroxymethyloxetane, tetrahydrofurfuryl alcohol, glycerol formal, solketal, 1,4-dioxane-2,3-diol, and dihydrolevoglucosenone.

[0054] These water-soluble low-molecular organic compounds can be used in combination of two or more.

[0055] The normal boiling point of the water-soluble low-molecular-weight organic compound is preferably 300° C. or lower, more preferably 270° C. or lower, more preferably 250° C. or lower, even more preferably 210° C. or lower, and particularly preferably 190° C. or lower. The lower limit of the normal boiling point of the water-soluble low-molecular-weight organic compound is not particularly limited, but is preferably 100° C. or higher, more preferably 110° C. or higher, more preferably 120° C. or higher, and even more preferably 150° C. or higher.

[0056] Furthermore, if the treatment liquid contains 30.0% by mass or less of a compound having a normal boiling point of 250°C or less as a water-soluble low-molecular-weight organic compound, the drying properties of the image formed from the inkjet ink composition can be further improved. Here, examples of water-soluble low-molecular-weight organic compounds having a standard boiling point of 250°C or less include, in addition to the alkanediols and alkylene glycol monoethers described below, 2-pyrrolidone (abbreviation: 2P, standard boiling point: 245°C, classification: amides, properties at 25°C: liquid), dimethyl sulfoxide (abbreviation: DMSO, standard boiling point: 188°C, classification: sulfur-containing solvents, properties at 25°C: liquid), 3-ethyl-3-oxetanemethanol (abbreviation: EOXM, standard boiling point: 220°C, classification: cyclic ethers, properties at 25°C: liquid), 1,2-hexanediol (abbreviation: 1,2HD, standard boiling point: 224°C, classification: alkanediols, properties at 25°C: liquid), and 1,5-pentanediol (abbreviation: 1,5PD, standard boiling point: 239°C, classification: alkanediols, properties at 25°C: liquid).

[0057] Furthermore, if the treatment liquid contains one or more water-soluble low-molecular-weight organic compounds selected from the group consisting of amides, sulfur-containing compounds, and cyclic ethers, each having a normal boiling point of 150°C or higher and 300°C or lower, the drying properties of the image formed from the inkjet ink composition can be further improved.

[0058] The lower limit of the content of the water-soluble low-molecular-weight organic compounds is preferably 10.0 mass% or more, more preferably 15.0 mass% or more, and even more preferably 20.0 mass% or more, based on the total mass of the treatment liquid, and the upper limit of the content of the water-soluble low-molecular-weight organic compounds is preferably 40.0 mass% or less, more preferably 35.0 mass% or less, and even more preferably 30.0 mass% or less, based on the total mass of the treatment liquid.

[0059] In the treatment liquid according to this embodiment, it is more preferable that the water-soluble low-molecular-weight organic compound contains an alkanediol having a standard boiling point of 210°C or less and an alkylene glycol monoether represented by general formula (1) having a standard boiling point of 210°C or less.

[0060] [ka] (In formula (1), R 1 represents a hydrocarbon group having 2 to 5 carbon atoms, and R 2 represents a hydrocarbon group having 1 to 2 carbon atoms, and n represents 1 or 2.

[0061] In the above general formula (1), R 1 is more preferably a linear or branched alkylene group having 2 to 5 carbon atoms. 1 is an alkylene group having 2 to 4 carbon atoms, and R 2 is more preferably an alkyl group having 1 carbon atom. Furthermore, n is more preferably 1.

[0062] Examples of alkanediols having a standard boiling point of 210°C or less include ethylene glycol (also known as ethane-1,2-diol, standard boiling point: 196°C, properties at 25°C: liquid, carbon number (hereinafter referred to as "C") 2), propylene glycol (abbreviation: PG, also known as propane-1,2-diol, standard boiling point: 188°C, properties at 25°C: liquid, C3), 1,2-butanediol (standard boiling point: 194°C, properties at 25°C: liquid, C4), 1,3-butylene glycol (abbreviation: 1,3BG, also known as 1,3-butanediol, standard boiling point: 207°C, properties at 25°C: liquid, C4), 2,3-butanediol (standard boiling point: 182°C, properties at 25°C: liquid, C4), 1,2-pentanediol (standard boiling point: 210°C, ℃, Properties at 25℃: Liquid, C5), 2,4-pentanediol (standard boiling point: 198℃, Properties at 25℃: Liquid, C5), 3-methyl-1,3-butanediol (also known as isoprene glycol, standard boiling point: 203℃, Properties at 25℃: Liquid, C5), neopentyl glycol (also known as 2,2-dimethyl-1,3-propanediol, standard boiling point: 210℃, Properties at 25℃: Solid [melting point 128℃], C5), 2-methylpentane-2,4-diol (also known as hexylene glycol, standard boiling point: 197℃, Properties at 25℃: Liquid, C6), and pinacol (also known as 2,3-dimethyl-2,3-butanediol, standard boiling point: 174℃, Properties at 25℃: Solid [melting point 43℃], C6).

[0063] The number of carbon atoms in the alkanediols having a normal boiling point of 210° C. or less is preferably 7 or less, and more preferably 2 or more and 6 or less.

[0064] The normal boiling point of the alkanediols having a normal boiling point of 210°C or less is preferably 150°C or more and 210°C or less, more preferably 160°C or more and 200°C or less, and even more preferably 170°C or more and 190°C or less.

[0065] Among the above alkanediols, one or more of propylene glycol, 2,3-butanediol, 1,2-butanediol, 1,3-butylene glycol, 3-methyl-1,3-butanediol, and 2-methylpentane-2,4-diol are preferred, and propylene glycol, 1,2-butanediol, or 2,3-butanediol are more preferred.

[0066] Examples of alkylene glycol monoethers having a standard boiling point of 210°C or less and represented by the above general formula (1) include 2-methoxyethanol (also known as ethylene glycol monomethyl ether, standard boiling point: 124°C, properties at 25°C: liquid, R1 = number of carbon atoms (hereinafter referred to as "C"); R2 = C1; n = 1), 2-ethoxyethanol (also known as ethylene glycol monoethyl ether, standard boiling point: 136°C, properties at 25°C: liquid, R1 = C2; R2 = C2; n = 1), 1-methoxy-2-propanol (abbreviated as PM, also known as propylene glycol monomethyl ether, standard boiling point: 124°C, properties at 25°C: liquid, R1 = C2; R2 = C2; n = 1), Glycol 1-monomethyl ether, standard boiling point: 120°C, properties at 25°C: liquid, R1=C3; R2=C1; n=1), 1-ethoxy-2-propanol (abbreviated as PE, also known as propylene glycol monoethyl ether, standard boiling point: 132°C, properties at 25°C: liquid, R1=C3; R2=C2; n=1), 2-methoxypropanol (abbreviated as propylene glycol 2-monomethyl ether, standard boiling point: 102°C, properties at 25°C: liquid, R1=C3; R2=C1; n=1), 3-methoxy-1-propanol (abbreviated as 1,3 -Propanediol monomethyl ether, standard boiling point: 153°C, properties at 25°C: liquid, R1=C3; R2=C1; n=1), 1-methoxy-2-butanol (also known as 1,2-butanediol 1-monomethyl ether, standard boiling point: 135°C, properties at 25°C: liquid, R1=C4; R2=C1; n=1), 2-methoxy-1-butanol (standard boiling point: 146°C, properties at 25°C: liquid, R1=C4; R2=C1; n=1), 3-methoxy-1-butanol (abbreviated as MB, also known as 1,3-butanediol 3-monomethyl ether, Standard boiling point: 158°C, Properties at 25°C: Liquid, R1=C4; R2=C1; n=1), 4-methoxy-1-butanol (also known as 1,4-butanediol monomethyl ether, Standard boiling point: 165°C, Properties at 25°C: Liquid, R1=C4; R2=C1; n=1), 3-methoxy-3-methyl-1-butanol (abbreviation: MMB, Standard boiling point: 174°C, Properties at 25°C: Liquid, R1=C5; R2=C1; n=1), diethylene glycol monomethyl ether (Standard boiling point: 194°C, Properties at 25°C: Liquid, R1=C2; R2=C1;n=2), diethylene glycol monoethyl ether (standard boiling point: 202°C, properties at 25°C: liquid, R1=C2; R2=C2; n=2), dipropylene glycol monomethyl ether (abbreviation: DPM, standard boiling point: 190°C, properties at 25°C: liquid, R1=C3; R2=C1; n=2), etc.;

[0067] The alkylene glycol monoethers represented by the general formula (1) above, which have a standard boiling point of 210°C or less, preferably have a standard boiling point of 110°C or more and 210°C or less, more preferably 130°C or more and 190°C or less, and even more preferably 140°C or more and 180°C or less.

[0068] Among the alkylene glycol monoethers, one or more of 3-methoxy-1-butanol, 1-methoxy-2-propanol, 1-ethoxy-2-propanol, 3-methoxy-3-methyl-1-butanol, and dipropylene glycol monomethyl ether are preferred, and 3-methoxy-1-butanol, 3-methoxy-3-methyl-1-butanol, or 1-methoxy-2-propanol are more preferred. When the alkylene glycol monoether is such a compound, it tends to have better abrasion resistance.

[0069] When an alkanediol having a normal boiling point of 210°C or less is used, its content is preferably 10.0% by mass or more and 25.0% by mass or less, based on the total mass of the treatment liquid. The lower limit is more preferably 11.0% by mass or more, even more preferably 12.0% by mass or more, particularly preferably 13.0% by mass or more, and especially preferably 14.0% by mass or more. The upper limit is more preferably 23.0% by mass or less, even more preferably 21.0% by mass or less, particularly preferably 19.0% by mass or less, and even more particularly preferably 17.0% by mass or less.

[0070] When the lower limit of the content of the alkanediols is 10% by mass or more, the drying properties of images formed using the inkjet ink composition can be further improved.

[0071] On the other hand, when an alkylene glycol monoether represented by the above general formula (1) having a normal boiling point of 210°C or less is added, its content is preferably 2.0% by mass or more and 10% by mass or less, based on the total mass of the treatment liquid. The lower limit is more preferably 2.5% by mass or more, even more preferably 3.0% by mass or more, particularly preferably 3.5% by mass or more, and even more particularly preferably 4.0% by mass or more. The upper limit is more preferably 9.0% by mass or less, even more preferably 8.0% by mass or less, particularly preferably 7.0% by mass or less, even more particularly preferably 6.0% by mass or less, and especially preferably 5.0% by mass or less.

[0072] When the lower limit of the content of alkylene glycol monoethers represented by the general formula (1) and having a normal boiling point of 210°C or less is 2.0 mass% or more, the wetting and spreading properties of the treatment liquid onto low-absorbency or non-absorbency recording media tend to be further improved.

[0073] Surfactants The treatment liquid may contain a surfactant. The surfactant has the function of reducing the surface tension of the treatment liquid and improving the wettability with the recording medium and the substrate, thereby improving the image quality of the image formed by the inkjet ink composition. Among surfactants, acetylene glycol-based surfactants, silicone-based surfactants, and fluorine-based surfactants can be preferably used.

[0074] The acetylene glycol surfactant is not particularly limited, but examples thereof include Surfynol 104, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG-50, 104S, 420, 440, 465, 485, SE, SE-F, 504, 61, DF37, CT111, CT121, CT131, CT136, TG, GA, and DF110D (all trade names, manufactured by Air Products & Chemicals Co.). , Olfine B, Y, P, A, STG, SPC, E1004, E1010, PD-001, PD-002W, PD-003, PD-004, EXP.4001, EXP.4036, EXP.4051, AF-103, AF-104, AK-02, SK-14, AE-3 (all trade names, manufactured by Nissin Chemical Industry Co., Ltd.), Acetylenol E00, E00P, E40, E100 (all trade names, manufactured by Kawaken Fine Chemicals Co., Ltd.).

[0075] The silicone surfactant is not particularly limited, but a polysiloxane compound is preferred. The polysiloxane compound is not particularly limited, but for example, a polyether-modified organosiloxane is exemplified. Commercially available products of the polyether-modified organosiloxane include, for example, BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, BYK-348, BYK-349, BYK-3420, BYK-3480, and BYK-3481 (all trade names, manufactured by BYK-Chemie Japan), K Examples include F-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF-642, KF-643, KF-6020, X-22-4515, KF-6011, KF-6012, KF-6015, and KF-6017 (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0076] As the fluorine-based surfactant, it is preferable to use a fluorine-modified polymer, and specific examples include BYK-3440 (manufactured by BYK Japan), Surflon S-241, S-242, S-243 (all trade names, manufactured by AGC Seimi Chemical Co., Ltd.), and Futergent 215M (manufactured by Neos Corporation).

[0077] The surfactants may be used alone or in combination of two or more.

[0078] When a surfactant is used, its content is preferably 0.2% by mass or more and 1.2% by mass or less relative to the total mass of the treatment liquid. The lower limit of the surfactant content is more preferably 0.3% by mass or more, even more preferably 0.4% by mass or more, and particularly preferably 0.5% by mass or more. The upper limit of the surfactant content is more preferably 1.0% by mass or less, even more preferably 0.8% by mass or less, and particularly preferably 0.7% by mass or less.

[0079] Furthermore, by including a silicone surfactant in the treatment liquid in an amount of 0.1% by mass to 4.0% by mass, both inclusive, relative to the total mass of the treatment liquid, the image quality of the image produced by the inkjet ink composition can be further improved. From the same perspective, it is particularly preferable that the surfactant content be 0.1% by mass to 0.8% by mass, both inclusive, of the silicone surfactant, and 0.1% by mass to 0.4% by mass, both inclusive, of the acetylene glycol surfactant, relative to the total mass of the treatment liquid.

[0080]

[0033] The treatment liquid may contain a cationic surfactant, which may have the effect of aggregating the components of the inkjet ink composition and can be used to supplement the aggregating action of the organic acid, organic acid polyvalent metal salt, and cationic polymer described above. It is more preferable to use the cationic surfactant to an extent that it does not affect the aggregating action of the organic acid, organic acid polyvalent metal salt, and cationic polymer described above.

[0081] Examples of cationic surfactants include primary, secondary, and tertiary amine salt compounds, alkylamine salts, dialkylamine salts, aliphatic amine salts, benzalkonium salts, quaternary ammonium salts, quaternary alkylammonium salts, alkylpyridinium salts, sulfonium salts, phosphonium salts, onium salts, and imidazolinium salts. Specific examples include hydrochlorides and acetates of laurylamine, coconut amine, and rosinamine, lauryltrimethylammonium chloride, cetyltrimethylammonium chloride, benzyltributylammonium chloride, benzalkonium chloride, dimethylethyllaurylammonium ethyl sulfate, dimethylethyloctylammonium ethyl sulfate, trimethyllaurylammonium hydrochloride, cetylpyridinium chloride, cetylpyridinium bromide, dihydroxyethyllaurylamine, decyldimethylbenzylammonium chloride, dodecyldimethylbenzylammonium chloride, tetradecyldimethylammonium chloride, hexadecyldimethylammonium chloride, and octadecyldimethylammonium chloride.

[0082] Other <Flocculant> The treatment liquid may contain, as a flocculant other than the above-mentioned organic acid, organic acid polyvalent metal salt, and cationic polymer, an inorganic acid, a metal salt of an inorganic acid, etc. However, since these flocculants may have a deliquescent effect, it is preferable to use them in as small an amount as possible.

[0083] <Other> The treatment liquid may contain components such as a pH adjuster, an antiseptic / mold inhibitor, a rust inhibitor, a chelating agent, an antioxidant, and an anti-mold agent.

[0084] 1.7. pH of treatment solution The pH of the treatment liquid of this embodiment is 5.5 or higher. The pH of the treatment liquid can be adjusted by selecting and adjusting the amounts of the above-mentioned organic acids, organic acid polyvalent metal salts, cationic polymers, pH adjusters, etc. A treatment liquid pH of 5.5 or higher can suppress deterioration of the container components that contain the treatment liquid, the components of the pathway through which the treatment liquid passes, and the recording medium to which the treatment liquid is applied. In other words, because the pH of the treatment liquid is not too low, component reliability can be ensured. The pH of the treatment liquid is preferably 5.5 or higher and 8 or lower, more preferably 5.5 or higher and 7.5 or lower, even more preferably 6.0 or higher and 7.5 or lower, and even more preferably 6.5 or higher and 7.5 or lower. This further facilitates suppressing deterioration of the container components and the recording medium.

[0085] On the other hand, the pH of the treatment liquid is more preferably within a specific range relative to the pH of the inkjet ink composition described below. That is, the pH of the treatment liquid is preferably lower than the pH of the inkjet ink composition described below, more preferably by 1.5 or more lower, even more preferably by 1.8 or more lower, and especially preferably by 2.0 or more lower. In this way, the aggregation ability of the components of the water-based inkjet ink composition containing the colorant is improved, and images of better quality can be obtained.

[0086] The pH of the treatment liquid is preferably 3 or less, more preferably 2.5 or less, and even more preferably 2.0 or less than the pH of the inkjet ink composition described below.

[0087] When the inkjet ink composition is alkaline, the organic acid in the treatment liquid serves to reduce the dispersion stability of the anionic dispersible components in the ink, causing the ink components to aggregate, but depending on the dispersible components contained in the ink, some are more likely to experience a decrease in dispersion stability when they come into contact with a low-pH (acidic) treatment liquid, while others are less likely to experience a decrease in dispersion stability. When the ink contains a component whose dispersion stability is less likely to decrease, the organic acid may be less reactive than the polyvalent metal salt.

[0088] 1.8.Effects The treatment liquid of this embodiment contains at least one selected from organic acid polyvalent metal salts and cationic polymers, and an organic acid, which provides good aggregation ability and drying properties for the components of the aqueous inkjet ink composition containing a colorant. This allows the abrasion resistance and image quality of the image formed using the inkjet ink composition to be improved. Furthermore, since the pH of this treatment liquid is not too low, component reliability can be ensured.

[0089] Polyvalent metal salts of organic acids and cationic polymers generally have a high pH, ​​but organic acids have a low pH. In the treatment liquid of this embodiment, a small amount of organic acid is used in the organic acid polyvalent metal salt or cationic polymer, thereby maintaining a pH of 5.5 or higher, thereby ensuring component reliability and providing excellent abrasion resistance (moisture resistance) for the image. However, if the organic acid content is too high, the pH becomes too low, resulting in poor component reliability. In this case, when the treatment liquid is used in an inkjet method, problems with head durability and rusting of metal parts inside the device are likely to occur.

[0090] 2. Recording method The recording method of this embodiment includes a treatment liquid application step of applying the above-described treatment liquid to a recording medium, and an ink application step of applying an inkjet ink composition to the recording medium by an inkjet method. The recording method of this embodiment uses the above-described treatment liquid. That is, the recording method of this embodiment is performed by applying an aqueous inkjet ink composition containing a colorant and the above-described treatment liquid to a recording medium.

[0091] 2.1. Recording Media The recording medium on which an image is formed by the recording method according to this embodiment may have a recording surface that absorbs a liquid such as an inkjet ink composition, or may not have a recording surface that absorbs a liquid. Therefore, the recording medium is not particularly limited, and examples thereof include liquid-absorbent recording media such as paper and cloth, low-liquid-absorbent recording media such as printing paper, and liquid-non-absorbent recording media such as metal, glass, film, and polymer.

[0092] However, the excellent effects of the recording method of this embodiment are more pronounced when recording an image on a recording medium that is low in liquid absorbency or non-liquid absorbent. That is, according to the recording method of this embodiment, even on a low-absorbency recording medium or a non-absorbent recording medium that is relatively prone to aggregation unevenness, it is possible to form an image with high image quality and good abrasion resistance, and the effect of improving the abrasion resistance and image quality of the image formed by the inkjet ink composition is more pronounced.

[0093] A recording medium with low liquid absorption or no liquid absorption refers to a recording medium that does not absorb liquid at all or absorbs almost no liquid. Quantitatively, a recording medium with low liquid absorption or no liquid absorption is one that absorbs liquid within 30 msec from the start of contact in the Bristow method. 1 / 2 Water absorption up to 10mL / m 2 This refers to a recording medium that is categorized as follows: The Bristow method is the most widely used method for measuring the amount of liquid absorbed in a short period of time, and is also adopted by the Japan Pulp and Paper Technical Association (JAPAN TAPPI). Details of the test method are described in Standard No. 51 "Paper and Paperboard - Liquid Absorbency Test Method - Bristow Method" of the "JAPAN TAPPI Paper and Pulp Test Methods 2000 Edition." In contrast, a liquid-absorbent recording medium refers to a recording medium that does not fall under the category of non-absorbent or low-absorbent. In this specification, low-absorbent and non-absorbent may be simply referred to as low-absorbent and non-absorbent.

[0094] Examples of non-liquid-absorbent recording media include plastic films and plates such as polyvinyl chloride, polyethylene, polypropylene, and polyethylene terephthalate (PET), metal plates such as iron, silver, copper, and aluminum, metal plates and plastic films made by vapor deposition of these metals, and alloy plates such as stainless steel and brass. Other examples include substrates such as paper coated with plastic, substrates such as paper with plastic film adhered to them, and plastic films without an absorption layer (receptor layer). Examples of plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0095] Further, examples of recording media with low liquid absorption include recording media having a coating layer (receiving layer) on the surface for receiving liquid. For example, a recording medium having a paper substrate includes printing paper, and a recording medium having a plastic film substrate includes polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc., with a hydrophilic polymer or the like coated on the surface, and silica, titanium, etc. particles coated together with a binder.

[0096] The liquid-absorbent recording medium is not particularly limited, but examples thereof include plain paper such as electrophotographic paper, which has high liquid permeability, inkjet paper (paper specifically for inkjet printing, which has an ink-absorbing layer made of silica particles or alumina particles, or an ink-absorbing layer made of a hydrophilic polymer such as polyvinyl alcohol (PVA) or polyvinylpyrrolidone (PVP)), art paper, coated paper, cast paper, etc., which are used in general offset printing and have relatively low liquid permeability. Further examples of the liquid-absorbent recording medium include fabrics and nonwoven fabrics.

[0097] The recording medium may be colorless and transparent, semi-transparent, colored and transparent, chromatic and opaque, achromatic and opaque, etc. The recording medium itself may be colored, semi-transparent, or transparent.

[0098] 2.2. Treatment liquid application process The treatment liquid application step is a step of applying the treatment liquid to the recording medium. The method of applying the treatment liquid to the recording medium can be any of non-contact and contact methods, such as an inkjet method, a coating method, a method of applying the treatment liquid to the recording medium using various sprays, a method of applying the treatment liquid by immersing the recording medium in the treatment liquid, and a method of applying the treatment liquid to the recording medium using a brush or the like, or a combination of these methods.

[0099] The treatment liquid application step may be carried out, for example, by ejecting the treatment liquid from an inkjet head 2 using an inkjet recording apparatus 1 as shown in Fig. 1. This is more preferable because it allows the treatment liquid and the inkjet ink composition to be applied to the recording medium using a single inkjet recording apparatus.

[0100] The treatment liquid application step may be performed before or after the ink composition is applied, or may be performed simultaneously with the application of the ink composition.

[0101] The amount of treatment liquid applied is 0.1 to 5 mg / inch per unit area of ​​the recording area of ​​the recording medium. 2 It is preferable that the density is 0.3 to 4 mg / inch. 2 More preferably, it is 0.5 to 3 mg / inch. 2 More preferably, it is 0.7 to 1.5 mg / inch. 2 It is particularly preferable that the maximum amount of treatment liquid applied per unit area of ​​the recording region of the recording medium during recording be within the above range.

[0102] 2.3.Ink application process The ink deposition step may be performed by any method as long as the inkjet ink composition is deposited while the recording head and the recording medium are scanned relative to each other. For example, it is preferable to use an inkjet head as the recording head and to perform the ink deposition by an inkjet method in which the inkjet ink composition is ejected from the inkjet head. In this way, it is possible to efficiently print a large number of types of small quantities using a small device. In addition to the inkjet method, the ink may also be deposited by an analog printing method or the like.

[0103] The inkjet method is a recording method in which minute droplets of inkjet ink are ejected from ejection nozzles of an inkjet head provided in a recording device such as an inkjet printer, and are caused to adhere to a recording medium or the like.

[0104] The ink deposition step can be easily carried out, for example, by using an inkjet recording apparatus 1 shown in Fig. 1, which is an embodiment of an inkjet recording apparatus described below, to eject ink from an inkjet head 2. Note that a composition used for recording by ejecting ink from an inkjet head using an inkjet method is called an inkjet ink composition.

[0105] The amount of inkjet ink composition applied is 1 to 40 mg / inch per unit area of ​​the recording region of the recording medium. 2 is preferably 2 to 30 mg / inch 2 More preferably, it is 4 to 20 mg / inch. 2 More preferably, it is 6 to 16 mg / inch. 2 It is particularly preferable that the maximum amount of ink deposited per unit area of ​​the recording region of the recording medium during recording be within the above range.

[0106] Furthermore, the ink deposition step of the recording method according to this embodiment preferably involves multiple main scans in which the relative position between the recording medium and the inkjet head is moved while the inkjet ink composition described above is ejected from the inkjet head, and the number of main scans in the same main scanning region is preferably 12 or less. The upper limit of the number of main scans in the same main scanning region is more preferably 11 or less, even more preferably 10 or less, and particularly preferably 9 or less. The lower limit is 1 or more, and is not particularly limited, but is preferably 2 or more, and more preferably 3 or more.

[0107] In the main scanning, the time for one main scanning pass is preferably 0.5 to 5 seconds, more preferably 1 to 4 seconds, and even more preferably 2 to 3 seconds. The time for one main scanning pass (also referred to as the main scanning time) is the time required for the head to move from a position facing one edge of the recording medium to a position facing the other edge of the recording medium in one main scanning pass.

[0108] The ink application step may be performed when the surface temperature of the recording medium is 50°C or less. That is, the ink application step may be performed by blowing air onto the recording medium without heating it, or may be performed with heating it. If heating is performed, the recording medium is heated so that the surface temperature is 50°C or less. In this way, an image with good image quality and abrasion resistance can be obtained with improved drying properties. The ink application step may be performed with cooling as necessary.

[0109] The ink application step is more preferably carried out so that the surface temperature of the recording medium when the inkjet ink composition is applied to the recording medium is 45° C. or less. That is, the ink application step may be carried out without heating the recording medium, or may be carried out with heating. Even when heating is carried out, it is preferable to heat the recording medium so that the surface temperature is 45° C. or less.

[0110] The upper limit of the surface temperature of the recording medium is more preferably 42° C. or less, even more preferably 38° C. or less, particularly preferably 32° C. or less, and even more particularly preferably 28° C. or less. The lower limit is preferably 20° C. or more, more preferably 23° C. or more, and particularly preferably 25° C. or more.

[0111] According to the recording method of this embodiment, the treatment liquid described above is used, so that an image of an inkjet ink composition having good image quality and abrasion resistance can be obtained.

[0112] The inkjet ink composition used in the recording method of this embodiment is an aqueous composition containing at least a colorant. The fact that it is aqueous, the water content, and the water content are the same as those of the treatment liquid described above, so further explanation will be omitted. In this specification, the "inkjet ink composition" may be abbreviated as "ink composition," "ink," etc.

[0113] <<Colorants>> The inkjet ink composition used in the recording method according to this embodiment contains a coloring material.

[0114] As the coloring material, either a pigment or a dye can be used, and examples of usable pigments include inorganic pigments such as carbon black and titanium white, organic pigments, oil-soluble dyes, acid dyes, direct dyes, reactive dyes, basic dyes, disperse dyes, and sublimation dyes. The ink composition preferably contains a pigment, and the pigment may be dispersed in a dispersing resin.

[0115] <Pigments> Examples of inorganic pigments that can be used include carbon blacks (CI Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, iron oxide, titanium oxide, zinc oxide, and silica.

[0116] Examples of organic pigments include quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, flavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, isoindolinone pigments, azomethine pigments, and azo pigments.

[0117] Specific examples of the organic pigment used in the ink composition include the following.

[0118] Examples of cyan pigments include CI Pigment Blue 1, 2, 3, 15:3, 15:4, 15:34, 16, 22, 60, etc.; CI Vat Blue 4, 60, etc., and preferably, one or a mixture of two or more selected from the group consisting of CI Pigment Blue 15:3, 15:4, and 60 can be exemplified.

[0119] Examples of magenta pigments include CI Pigment Red 5, 7, 12, 48(Ca), 48(Mn), 57(Ca), 57:1, 112, 122, 123, 168, 184, 202, and CI Pigment Violet 19. Preferred examples include one or a mixture of two or more pigments selected from the group consisting of CI Pigment Red 122, 202, and 209, and CI Pigment Violet 19.

[0120] Examples of yellow pigments include CI Pigment Yellow 1, 2, 3, 12, 13, 14C, 16, 17, 73, 74, 75, 83, 93, 95, 97, 98, 119, 110, 114, 128, 129, 138, 150, 151, 154, 155, 180, and 185. Preferred examples include one or a mixture of two or more selected from the group consisting of CI Pigment Yellow 74, 109, 110, 128, 138, 150, and 180.

[0121] Pigments of other colors can also be used, such as orange pigments and green pigments.

[0122] The pigments exemplified above are examples of suitable pigments, but are not limited to these. These pigments may be used alone or in combination with a dye.

[0123] The pigment may be dispersed using a dispersant selected from a water-soluble resin, a surfactant, etc., or may be dispersed as a self-dispersing pigment by oxidizing or sulfonating the pigment surface with ozone, hypochlorous acid, fuming sulfuric acid, etc. Surfactants that can be used as dispersants may be surfactants that may be contained in the ink composition described below.

[0124] The water-soluble resin used in the dispersant may contain the following hydrophilic group, hydrophilic group-containing monomer, and hydrophobic group-containing monomer.

[0125] (Hydrophilic Group and Hydrophilic Group-Containing Monomer) The water-soluble resin may contain hydrophilic groups such as hydroxyl groups, carboxyl groups, sulfonic acid groups, and phosphate groups to impart hydrophilicity. Examples of hydroxyl group-containing monomers that can be used in the water-soluble resin include 2-hydroxyethyl (meth)acrylate, 2-(2-hydroxyethoxy)ethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, diethylene glycol (meth)acrylate, ethyl 2-hydroxymethyl-2-propanoate, and 2,3-dihydroxypropyl (meth)acrylate. Examples of carboxyl group-containing monomers that can be used in the polymer include acrylic acid, methacrylic acid, crotonic acid, propyl (meth)acrylic acid, isopropyl (meth)acrylic acid, itaconic acid, and fumaric acid. Other examples include ω-carboxy-polycaprolactone mono(meth)acrylate, monohydroxyethyl phthalate (meth)acrylate, and (meth)acrylic acid dimer. These may be used alone or in combination of two or more; however, acrylic acid and / or methacrylic acid are preferred.

[0126] (Hydrophobic group-containing monomer) The water-soluble resin preferably has a hydrophobic group. The hydrophobic group refers to a group that is more hydrophobic than the hydrophilic group contained in the water-soluble resin. Examples of such hydrophobic groups include aromatic groups, cyclic aliphatic hydrocarbon groups having 5 or more carbon atoms, and linear aliphatic hydrocarbon groups having 8 or more carbon atoms. Examples of aromatic groups include substituted or unsubstituted benzyl groups. Examples of linear aliphatic hydrocarbon groups include substituted or unsubstituted cycloalkyl groups such as cyclopentane, cyclohexane, and cycloheptane. Examples of linear aliphatic hydrocarbon groups include alkyl groups such as ethylhexyl, octyl, nonyl, decyl, undecyl, and dodecyl.

[0127] Examples of hydrophobic group-containing monomers in water-soluble resins include those containing aromatic groups such as styrene, benzyl (meth)acrylate, paracumylphenoxyethylene glycol (meth)acrylate, and phenol EO-modified acrylate. Examples of those containing cyclic aliphatic hydrocarbon groups include cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cycloheptane (meth)acrylate, and isobornyl meth(meth)acrylate. Examples of those containing chain aliphatic hydrocarbon groups include octyl (meth)acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, ethylhexyl (meth)acrylate, ethyl (meth)acrylate, and butyl (meth)acrylate, as well as urethane-modified (meth)acrylate and epoxy-modified (meth)acrylate. It is preferable that the hydrophobic group-containing monomer does not contain a hydroxyl group or a carboxyl group.

[0128] [Method for producing water-soluble resin] The water-soluble resin usable as a dispersant can be obtained by applying a conventionally known polymer polymerization method. That is, the water-soluble resin can be obtained by solution polymerization or emulsion polymerization. As the polymerization initiator, in addition to potassium persulfate or ammonium persulfate, general initiators used in radical polymerization, such as hydrogen persulfate, azobisisobutyronitrile, azobisisovaleronitrile, azobisacetoxyphenylethane, azobismethylbutanamide dihydrochloride tetrahydrate, azobismethylbutyronitrile, azobiscyclohexanecarbonitrile, dimethylazobisisobutyrate, azobiscyanovaleric acid, benzoyl peroxide, dibutyl peroxide, peracetic acid, cumene hydroperoxide, t-butylhydroxyperoxide, and paramenthane hydroperoxide, can be used.

[0129] The polymerization can be obtained by solution polymerization in a solvent such as an aliphatic hydrocarbon solvent, an aromatic hydrocarbon solvent, an ester solvent, a ketone solvent, an alcohol solvent, or an aprotic solvent in the presence of the above-mentioned polymerization initiator. The polymerization is typically carried out at 30 to 100°C, preferably 50 to 80°C, for 1 to 10 hours, and the temperature is appropriately selected depending on the type of polymerization initiator, monomer, and solvent used. The polymerization is preferably carried out under an inert gas atmosphere such as nitrogen. After polymerization, the copolymer can be isolated from the reaction solution by known methods such as reprecipitation or solvent distillation. The obtained copolymer can also be purified by removing unreacted monomers and the like by reprecipitation, membrane separation, chromatography, extraction, or the like.

[0130] It is preferable that polymers having acidic groups such as carboxyl groups be ionized with a neutralizing agent (alkali agent). Examples of neutralizing agents (alkali agents) that can be used include inorganic alkalis such as sodium hydroxide, potassium hydroxide, and lithium hydroxide, ammonia, and organic amines such as trimethylamine, tripropylamine, tributylamine, diethylmethylamine, diethylmethylamine, dipropylmethylamine, dibutylmethylamine, dipropylbutylamine, triethanolamine, tripropanolamine, and tributanolamine. When synthesizing this polymer, the composition of these polymerizable monomers is designed to be a preferred monomer composition.

[0131] [Resin-coated pigment and pigment dispersion in which the resin-coated pigment is dispersed] In the inkjet ink composition according to this embodiment, the pigment may be dispersed as a resin-coated pigment coated with a water-soluble resin. The resin-coated pigment is a pigment that is coated or surrounded by a polymer compound and can be dispersed in an aqueous medium, and the pigment dispersion has an aqueous phase in which the resin-coated pigment is dispersed.

[0132] (Method of manufacturing resin-coated pigment) The resin-coated pigment can be produced by a known physical, mechanical, or chemical method, including, but not limited to, a phase separation method (coacervation), a submerged drying method (interfacial precipitation method), a spray drying method, a pan coating method, a submerged curing coating method, an interfacial polymerization method, an in situ method, and an ultrasonic method.

[0133] For example, a resin-coated pigment can be obtained by polymerizing a water-soluble resin monomer in the presence of the pigment through emulsion polymerization or the like. Specifically, a polymerizable monomer, a polymerization initiator, and optionally a chain transfer agent are added to a pigment dispersion, and the polymerization reaction is carried out under predetermined conditions. The pigment dispersion can also be formed using a dispersant having a polymerizable group copolymerizable with other monomers. Specifically, a pulverization process is carried out by irradiating ultrasonic waves for a predetermined period of time in a reaction vessel equipped with an ultrasonic generator, a stirrer, and a temperature regulator, using the pigment, water, and optionally a polymerizable surfactant. In addition to ultrasonic dispersion using an ultrasonic generator, dispersion methods using common dispersers such as a ball mill, roll mill, or Eiger mill, as well as dispersion methods using a high-speed mixer, bead mill, sand mill, or roll mill can also be used. Next, a monomer and a polymerization initiator are further added, and the polymerization reaction is carried out at a predetermined polymerization temperature, thereby obtaining a suitable pigment. A chain transfer agent can also be added to the reaction vessel.

[0134] A preferred method for producing a resin-coated pigment is phase inversion emulsification. The water-soluble resin used in phase inversion emulsification is preferably synthesized by solution polymerization. Furthermore, it is preferably synthesized by solution polymerization using a radical polymerization initiator. The resin dispersion obtained by solution polymerization can be used directly in the pigment dispersion process. An example of the phase inversion emulsification process includes a pigment dispersion process in which a mixed liquid containing a resin, a pigment, an organic solvent, and an excess amount of water relative to the organic solvent is prepared, and the pigment is dispersed in the aqueous phase of the mixed liquid in a state where at least a portion of the resin coats the pigment. The resin and pigment present in the aqueous phase of the pigment dispersion thus obtained can be used together with at least a portion of the aqueous phase or in a state separated from the aqueous phase to prepare an ink composition. During phase inversion emulsification, the organic solvent can be distilled off.

[0135] The pigment dispersion process can be carried out, for example, as follows: That is, a pigment dispersion (organic solvent) is prepared by dispersing a pigment in an organic solvent, a resin dispersion is prepared by dispersing or dissolving a resin in water, and the pigment dispersion (organic solvent) and the resin dispersion are mixed. In this manner, a state in which the resin is unevenly distributed near the pigment surface and coats the pigment can be formed in the aqueous phase (phase inversion emulsification). Alternatively, a dispersion of a pigment and a resin in an organic solvent (optionally containing a neutralizer, water, or a surfactant, or a combination of these) can be prepared, and then mixed with a large amount of water (preferably in excess of the organic solvent) to transfer the pigment and resin from the organic solvent phase to the aqueous phase, thereby forming a state in which the pigment is coated (encapsulated) by the resin in the aqueous phase.

[0136] In the pigment dispersion step, the pigment is dispersed in the aqueous phase by stirring the pigment in a mixed medium of an organic solvent and water using various dispersing means. In addition to ultrasonic waves, a high-pressure homogenizer, an ultra-high-pressure homogenizer, a high-speed mixer, a sand mill, a bead mill, or a roll mill can be appropriately selected and used to disperse the pigment. The pigment dispersion step in the phase inversion emulsification method is preferably carried out using a device that mixes and stirs while applying appropriate shear so that the resin and the pigment come into contact with each other and the resin can adhere to the pigment surface.

[0137] The organic solvent used in the process of preparing the pigment dispersion is not particularly limited, but in consideration of the ease of distilling off the organic solvent in the end, an organic solvent with a low boiling point is preferred. Examples of the organic solvent include ketone organic solvents such as acetone and methyl ethyl ketone, ester organic solvents such as ethyl acetate, alcohol organic solvents such as ethanol and isopropyl alcohol, and aromatic hydrocarbon organic solvents such as benzene.

[0138] As already mentioned, in order to dissolve or disperse a resin having an acidic group such as a carboxyl group in water, various inorganic alkalis and various organic amines can be used as neutralizing agents, but inorganic alkalis are preferably used.

[0139] To separate the resin and pigment (resin-coated pigment) from the aqueous phase, the organic solvent can be removed from the pigment dispersion having an aqueous phase in which the resin-coated pigment is dispersed by a method such as heating, or an appropriate method such as centrifugation, water washing, ultrafiltration, or pressure filtration can be selected.

[0140] <dye> The inkjet ink composition used in the recording method according to this embodiment may contain a dye as a colorant. The dye is not particularly limited, and acid dyes, direct dyes, reactive dyes, basic dyes, and disperse dyes can be used. Examples of dyes include CI Acid Yellow 17, 23, 42, 44, 79, and 142, CI Acid Red 52, 80, 82, 249, 254, and 289, CI Acid Blue 9, 45, and 249, CI Acid Black 1, 2, 24, and 94, CI Food Black 1 and 2, CI Direct Yellow 1, 12, 24, 33, 50, 55, 58, 86, 132, 142, 144, and 173, and the like. CI Direct Red 1, 4, 9, 80, 81, 132, 225, 227; CI Direct Blue 1, 2, 15, 71, 86, 87, 98, 165, 199, 202; CI Direct Black 19, 38, 51, 71, 154, 168, 171, 195; CI Reactive Red 14, 32, 55, 79, 141, 249; and CI Reactive Black 3, 4, 35.

[0141] The content of the colorant can be adjusted appropriately depending on the application, but is preferably from 0.1% by mass to 17.0% by mass, more preferably from 0.2% by mass to 15.0% by mass, even more preferably from 1.0% by mass to 10.0% by mass, and particularly preferably from 2.0% by mass to 5.0% by mass, relative to the total mass of the ink composition.

[0142] <<Other ingredients>> The inkjet ink composition used in the recording method of this embodiment may contain a water-soluble low-molecular-weight compound, a surfactant, a water-dispersible resin, and other components. The water-soluble low-molecular-weight compound and surfactant that may be contained in the inkjet ink composition are the same as those described above for the treatment liquid, and can be used without any particular limitation as long as they can be used as an inkjet ink composition.

[0143] <Water dispersible resin> The inkjet ink composition may contain a water-dispersible resin. When the inkjet ink composition contains a water-dispersible resin, it tends to have better abrasion resistance, which is preferable.

[0144] Examples of the water-dispersible resin include acrylic resins, urethane resins, polyester resins, olefin resins, fluorene resins, rosin-modified resins, terpene resins, polyamide resins, epoxy resins, vinyl chloride resins, ethylene vinyl acetate resins, etc. Water-dispersible resins are often handled in the form of an emulsion, but they may also be in the form of a powder or in a form that is completely soluble in water.

[0145] Acrylic resin is a general term for polymers obtained by polymerizing at least an acrylic monomer such as (meth)acrylic acid or a (meth)acrylic acid ester as one component. Examples include resins obtained from acrylic monomers and copolymers of acrylic monomers with other monomers. Examples include acrylic-vinyl resins, which are copolymers of acrylic monomers and vinyl monomers. Further examples include copolymers with vinyl monomers such as styrene. Acrylic monomers that can be used include acrylamide and acrylonitrile.

[0146] As the resin emulsion made from an acrylic resin as a raw material, a commercially available product may be used, and may be selected from, for example, FK-854, Mowinyl 952B, 718A (trade names, manufactured by Japan Coating Resins Co., Ltd.), Nipol LX852, LX874 (trade names, manufactured by Nippon Zeon Co., Ltd.), Polysol AT860 (manufactured by Showa Denko K.K.), Boncoat AN-1190S, YG-651, AC-501, AN-1170, 4001 (trade names, acrylic resin emulsions, manufactured by DIC Corporation), and the like.

[0147] In this specification, the acrylic resin may be a styrene-acrylic resin as described above. Also, as described above, in this specification, the term "(meth)acrylic" means at least one of acrylic and methacrylic.

[0148] Styrene-acrylic resins are copolymers obtained from a styrene monomer and an acrylic monomer, and examples thereof include styrene-acrylic acid copolymer, styrene-methacrylic acid copolymer, styrene-methacrylic acid-acrylate copolymer, styrene-α-methylstyrene-acrylic acid copolymer, and styrene-α-methylstyrene-acrylic acid-acrylate copolymer. As the styrene-acrylic resin, commercially available products may be used, and examples thereof include JONCRYL 62J, 7100, 390, 711, 511, 7001, 631, 632, 741, 450, 840, 74J, HRC-1645J, 734, 852, 7600, 775, 537J, 1535, PDX-7630A, 352J, 352D, PDX-7145, 538J, 7640, 7641, 631, 790, 780, and 7610 (trade names, manufactured by BASF), and Mowinyl 966A and 975N (trade names, manufactured by Japan Coating Resins Co., Ltd.).

[0149] Urethane resin is a general term for resins having urethane bonds. In addition to urethane bonds, the urethane resin may be a polyether urethane resin containing ether bonds in the main chain, a polyester urethane resin containing ester bonds in the main chain, or a polycarbonate urethane resin containing carbonate bonds in the main chain. As the urethane-based resin, commercially available products may be used, and may be selected from commercially available products such as Superflex 210, 460, 460s, 840, and E-4000 (trade names, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), Rezamin D-1060, D-2020, D-4080, D-4200, D-6300, and D-6455 (trade names, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.), Takelac WS-6020, WS-6021, and W-512-A-6 (trade names, manufactured by Mitsui Chemicals Polyurethanes Inc.), Sancure 2710 (trade name, manufactured by Lubrizol), and Parmarin UA-150 (trade name, manufactured by Sanyo Chemical Industries, Ltd.).

[0150] The polyester resin is not particularly limited, but examples thereof include polyethylene terephthalate. Commercially available polyester resins may be used, such as Elitel KT8701 (trade name, manufactured by Unitika Ltd.).

[0151] Examples of olefin resins include resins produced from olefins such as ethylene, propylene, and butylene, or derivatives thereof, and specifically include polyethylene resins, polypropylene resins, and polybutylene resins.

[0152] Commercially available olefin resins include the AQUACER series, such as AQUACER 513 (polyethylene resin, average particle size 100 nm to 200 nm, melting point 130°C, solids content 30%), AQUACER 507, AQUACER 515, AQUACER 840, and AQUACER 1547 (all trade names, manufactured by BYK Japan Co., Ltd.); the Hitech series, such as Hitech E-7025P, Hitech E-2213, Hitech E-6500, Hitech E-6314, Hitech E-9460, Hitech E-9015, Hitech E-4A, Hitech E-5403P, and Hitech E-8237 (all trade names, manufactured by Toho Chemical Industry Co., Ltd., polyethylene resins); and Nopcoat PEM-17 (trade name, manufactured by San Nopco, polyethylene emulsion, average particle size 40 nm).

[0153] The water-dispersible resin is preferably supplied in the form of an emulsion. Examples of commercially available resin emulsions include Microgel E-1002 and E-5002 (product names of Nippon Paint Co., Ltd., styrene-acrylic resin emulsions), Boncoat AN-1190S, YG-651, AC-501, AN-1170, 4001, and 5454 (product names of DIC Corporation, styrene-acrylic resin emulsions), Polysol AM-710, AM-920, AM-2300, AP-4735, AT-860, and PSASE-4210E (acrylic resin emulsions). emulsion), Polysol AP-7020 (styrene-acrylic resin emulsion), Polysol SH-502 (vinyl acetate resin emulsion), Polysol AD-13, AD-2, AD-10, AD-96, AD-17, AD-70 (ethylene-vinyl acetate resin emulsion), Polysol PSASE-6010 (ethylene-vinyl acetate resin emulsion) (trade name, manufactured by Showa Denko K.K.), Polysol SAE1014 (trade name, styrene-acrylic resin emulsion, manufactured by Nippon Zeon Co., Ltd.), Saivinol SK-200 (trade name, acrylic resin emulsion, Saiden Chemical Co., Ltd.), AE-120A (JSR Corporation trade name, acrylic resin emulsion), AE373D (E-Tech Co., Ltd. trade name, carboxy-modified styrene-acrylic resin emulsion), Seikadyne 1900W (Dainichiseika Color & Chemicals Mfg. Co., Ltd. trade name, ethylene-vinyl acetate resin emulsion), Vinyblan 2682 (acrylic resin emulsion), Vinyblan 2886 (vinyl acetate-acrylic resin emulsion), Vinyblan 5202 (acetic acid acrylic resin emulsion) (Nissin Chemical Industry Co., Ltd. trade name), Vinyblan 700, 2586 (Nissin Chemical Industry Co., Ltd.), Ely Ether KA-5071S, KT-8803, KT-9204, KT-8701, KT-8904, KT-0507 (trade name of Unitika Ltd., polyester resin emulsion), Hi-Tec SN-2002 (trade name of Toho Chemical Co., Ltd., polyester resin emulsion), Takelac W-6020, W-635, W-6061, W-605, W-635, W-6021 (trade name of Mitsui Chemicals Polyurethanes, urethane resin emulsion), Superflex 870, 800, 150, 420, 460, 470, 610, 620, 700 (trade name of Daiichi Kogyo Seiyaku Co., Ltd.,Urethane resin emulsion), Permarin UA-150 (Sanyo Chemical Industries, Ltd., urethane resin emulsion), Sancure 2710 (Lubrizol Japan, urethane resin emulsion), NeoRez R-9660, R-9637, R-940 (Kusumoto Chemicals Co., Ltd., urethane resin emulsion), Adeka Bontitor HUX-380, 290K (ADEKA Corporation, urethane resin emulsion), Mowinyl 966A, Mowinyl 7320 (Japan Coating Resins Co., Ltd.), Joncryl 7100, 390, 711, 511, 7001, 632, 741, 450, 840, 74J, HRC-1645J, 734, 852, 7600, 775, 537J, 1535, PDX The binder may be selected from the group consisting of PDX-7630A, 352J, 352D, PDX-7145, 538J, 7640, 7641, 631, 790, 780, and 7610 (all manufactured by BASF), NK Binder R-5HN (manufactured by Shin-Nakamura Chemical Co., Ltd.), Hydran WLS-210 (non-crosslinked polyurethane manufactured by DIC Corporation), and Joncryl 7610 (manufactured by BASF).

[0154] The water-dispersible resin may be used alone or in combination of two or more kinds.

[0155] The inkjet ink composition according to this embodiment preferably contains at least one water-dispersible resin selected from acrylic, urethane, polyester, and olefinic resins, and more preferably at least one water-dispersible resin selected from acrylic and olefinic resins. Water-dispersible resins selected from such resins tend to have particularly excellent abrasion resistance.

[0156] The glass transition temperature (Tg) of the water-dispersible resin is preferably 150°C or lower, more preferably 120°C or lower, because it is easily formed into a film on a recording medium and has excellent adhesion, resulting in better abrasion resistance. On the other hand, it is preferably -50°C or higher, more preferably 0°C or higher, and even more preferably 20°C or higher, because it has hardness, resulting in better abrasion resistance and better resistance to blocking show-through. The glass transition temperature (Tg) can be confirmed by a standard method using differential scanning calorimetry (DSC) or the like.

[0157] When a water-dispersible resin is used, its content, calculated as solid content, is preferably from 0.1 to 20% by mass, more preferably from 1.0 to 15.0% by mass, even more preferably from 2.0 to 10.0% by mass, and particularly preferably from 3.0 to 8.0% by mass, relative to the total mass of the ink composition. When the content of the water-dispersible resin is within the above range, the abrasion resistance tends to be better.

[0158] <Other ingredients> The inkjet ink composition according to this embodiment may contain various additives as appropriate in addition to the components described above, such as antifoaming agents, solubilizing agents, viscosity adjusters, pH adjusters, antioxidants, preservatives, antifungal agents, corrosion inhibitors, and chelating agents for capturing metal ions that affect dispersion.

[0159] The pH of the inkjet ink composition can be adjusted by selecting the components such as the pH adjuster described above and adjusting the amount of each component. There are no particular restrictions on the pH of the inkjet ink composition, but it is more preferable that the pH be 1.5 or more higher than the pH of the treatment liquid. The difference between the pH of the inkjet ink composition and the pH of the treatment liquid may be set by adjusting either the pH of the treatment liquid or the pH of the inkjet ink composition.

[0160] The pH of the inkjet ink composition is, for example, preferably 7 or more and 10 or less, and more preferably 7.5 or more and 9.5 or less.

[0161] [Manufacturing method] The inkjet ink composition can be obtained, for example, by mixing the above-mentioned components in any order and, if necessary, removing impurities by filtration or the like. A suitable method for mixing the components is to sequentially add the materials to a container equipped with a stirring device such as a mechanical stirrer or a magnetic stirrer and stir and mix them. As a filtration method, centrifugal filtration, filter filtration, etc. can be used as necessary.

[0162] [Physical Properties] From the viewpoint of balancing image quality and reliability as an inkjet recording ink, the inkjet ink composition preferably has a surface tension of 18 mN / m to 40 mN / m at 20° C., more preferably 20 mN / m to 35 mN / m, and even more preferably 22 mN / m to 33 mN / m. The surface tension can be measured, for example, by using an automatic surface tensiometer CBVP-Z (trade name, manufactured by Kyowa Interface Science Co., Ltd.) to check the surface tension when a platinum plate is wetted with the ink in an environment of 20° C.

[0163] From the same viewpoint, the viscosity of the inkjet ink composition according to this embodiment at 20° C. is preferably from 3 mPa·s to 10 mPa·s, and more preferably from 3 mPa·s to 8 mPa·s. The viscosity can be measured at 20° C. using, for example, a viscoelasticity tester MCR-300 (trade name, manufactured by Pysica).

[0164] 2.4.Other processes The recording method of this embodiment may include the following steps in addition to the treatment liquid application step and the ink application step.

[0165] 2.4.1.Primary drying process The recording method according to this embodiment may include a primary drying step. By including such a step, the drying properties of the ink can be improved at an early stage after the inkjet ink composition is applied to the recording medium, making it easier to obtain excellent image quality.

[0166] The primary drying step is a step of drying the ink at an early stage of applying the ink-jet ink composition to a recording medium, and is a drying step for drying at least a portion of the solvent component of the ink applied to the recording medium, at least to an extent that the flow of the ink is reduced.

[0167] Examples of means for the primary drying step include a method based on blowing room temperature air (room temperature air) or heated air (hot air) onto the recording medium using a fan or the like, a method based on heating the recording medium using an IR heater, microwave radiation, a platen heater, or the like, or a combination of these. Note that the primary drying step in this embodiment is not particularly limited as long as it can improve the drying properties of the ink, and does not necessarily have to involve heating. Therefore, in the primary drying step in this embodiment, a method based on blowing room temperature air may be used alone. It is more preferable that the primary drying step be a method that involves heating.

[0168] When air is blown as the primary drying step, the air velocity is preferably 0.5 to 10 m / s, more preferably 1 to 5 m / s, and even more preferably 2 to 3 m / s. The air velocity is the air velocity near the surface of the recording medium. When the air velocity is above the above range, image quality and reduction of head condensation are more excellent, which is preferable. When the air velocity is below the above range, clogging recovery is more excellent, which is preferable. The temperature of the blown air is preferably 50° C. or lower, and more preferably 10° C. or higher, more preferably 15 to 45° C., and even more preferably 20 to 49° C. The temperature of the blown air may be room temperature.

[0169] When heating is involved in the primary drying step, the ink may be applied to a heated recording medium, or may be heated immediately after application. In the primary drying step, it is preferable that heating of the ink droplets that have landed on the recording medium is started within 0.5 seconds at the latest after the ink droplets have landed on the recording medium.

[0170] When heating is performed as the primary drying step, the heating may be performed at least either before the ink application step, simultaneously with the application, or shortly after the application, and preferably simultaneously. The ink application step can be performed in such a heating order.

[0171] Furthermore, when heating is performed as the primary drying step, it is preferable to set the temperature within the range described above as the surface temperature of the recording medium in the ink application step. Note that the heating temperature in the primary drying step is the surface temperature of the recording medium when the ink is applied when the ink is applied to the heated recording medium, or the surface temperature of the recording medium when heating is performed when heating is performed soon after the ink is applied. It is also the maximum temperature during heating in the primary drying step.

[0172] 2.4.2. Post-drying process The recording method according to this embodiment may also include a post-drying step in which the surface of the recording medium, onto which the inkjet ink composition has been adhered, is heated to a temperature of 60° C. or higher and 120° C. or lower, preferably 80° C. or higher and 110° C. or lower, after passing through a platen. This is preferable because it tends to improve the drying properties and produce a recorded product with better abrasion resistance.

[0173] The post-drying process is a process for completing the recording and drying the recorded matter sufficiently to enable it to be used. The post-drying process is a drying process for sufficiently drying the solvent component of the ink and heating the resin that may be contained in the ink to form a flat ink coating.

[0174] The post-drying step is preferably initiated on the surface of the recording medium including a certain point on the recording medium to which ink has been applied in the ink application step described above, after the certain point has passed the platen. For example, in the inkjet recording apparatus 1 shown in Figures 1 and 2, ink is applied to a certain point on the recording medium M by the inkjet head 2 facing the platen 11, and after the certain point of the recording medium M to which ink has been applied has passed the platen 11, the post-drying step is initiated on the surface of the recording medium M including the certain point by the heater 5.

[0175] The heating of the recording medium in the post-drying step can be carried out using an appropriate heating means, for example, when an inkjet recording apparatus is used, and can also be carried out by any appropriate heating means, not limited to the heating means provided in the inkjet recording apparatus.

[0176] In the post-drying step, the lower limit of the surface temperature of the recording medium is preferably 50° C. or higher, more preferably 60° C. or higher, even more preferably 70° C. or higher, and particularly preferably 75° C. or higher. The upper limit of the surface temperature of the recording medium is preferably 120° C. or lower, more preferably 110° C. or lower, even more preferably 100° C. or lower, and particularly preferably 90° C. or lower.

[0177] It is preferable that the temperature preferred in the primary drying step is different from the temperature preferred in the post-drying step.

[0178] 2.5. Inkjet recording device An example of an inkjet recording apparatus that can be used in the recording method according to this embodiment will be described with reference to the drawings.

[0179] FIG. 1 is a schematic cross-sectional view showing an inkjet recording apparatus. FIG. 2 is a perspective view showing an example of the configuration of the periphery of the carriage of the inkjet recording apparatus 1 of FIG. 1. As shown in FIGS. 1 and 2, the inkjet recording apparatus 1 includes an inkjet head 2, an IR heater 3, a platen heater 4, a heating heater 5, a cooling fan 6, a preheater 7, a ventilation fan 8, a carriage 9, a platen 11, a carriage movement mechanism 13, a transport means 14, and a control unit CONT. The operation of the entire inkjet recording apparatus 1 is controlled by the control unit CONT shown in FIG. 2.

[0180] The inkjet head 2 is configured to perform recording on the recording medium M by ejecting and depositing the treatment liquid and inkjet ink composition from the nozzles of the inkjet head 2. In this embodiment, the inkjet head 2 is a serial type inkjet head, and deposits the ink on the recording medium M by scanning multiple times in the main scanning direction relative to the recording medium M. The inkjet head 2 is mounted on a carriage 9 shown in FIG. 2. The inkjet head 2 is scanned multiple times in the main scanning direction relative to the recording medium M by the operation of a carriage movement mechanism 13 that moves the carriage 9 in the medium width direction of the recording medium M. The medium width direction is the main scanning direction of the inkjet head 2. Scanning in the main scanning direction is also called main scanning.

[0181] Here, the main scanning direction is the direction in which the carriage 9 carrying the inkjet head 2 moves. In FIG. 1, this direction intersects with the sub-scanning direction, which is the transport direction of the recording medium M, indicated by the arrow SS. In FIG. 2, the width direction of the recording medium M, i.e., the direction indicated by S1-S2, is the main scanning direction MS, and the direction indicated by T1→T2 is the sub-scanning direction SS. Note that scanning is performed in the main scanning direction, i.e., in either the direction indicated by the arrow S1 or the arrow S2, in one scan. Recording is performed on the recording medium M by repeating the main scan of the inkjet head 2 and the sub-scan, which transports the recording medium M, multiple times. In other words, the treatment liquid application process and the ink application process are performed by multiple main scans in which the inkjet head 2 moves in the main scanning direction, and multiple sub-scans in which the recording medium M moves in the sub-scanning direction that intersects the main scanning direction.

[0182] The cartridges 12 that supply the inkjet ink composition and treatment liquid to the inkjet head 2 respectively include a plurality of independent cartridges. The cartridges 12 are detachably mounted on a carriage 9 that mounts the inkjet head 2. Each of the plurality of cartridges is filled with a different type of inkjet ink composition or treatment liquid, and the inkjet ink composition and treatment liquid are supplied from the cartridges 12 to each nozzle. Note that in this embodiment, an example is shown in which the cartridge 12 is mounted on the carriage 9, but this is not limiting, and the cartridge 12 may be provided in a location other than the carriage 9 and may supply the ink to each nozzle via a supply pipe (not shown).

[0183] A conventionally known method can be used for ejection from the inkjet head 2. In this embodiment, a method of ejecting droplets using the vibration of a piezoelectric element, that is, an ejection method of forming ink droplets by mechanical deformation of an electrostrictive element, is used.

[0184] The inkjet recording apparatus 1 is equipped with a ventilation fan 8, an IR heater 3, and a platen heater 4 for drying the inkjet ink composition ejected from the inkjet head 2 and attached to the recording medium M. The primary drying step can be carried out by using an appropriate combination of the ventilation fan 8, the IR heater 3, and the platen heater 4. In the primary drying step, it is not always necessary to heat the recording medium M, and the ventilation fan 8 may be used alone to blow air at room temperature.

[0185] Note that by using the IR heater 3, the recording medium M can be radiatively heated by radiating infrared rays from the inkjet head 2 side. This makes it easier for the inkjet head 2 to be heated at the same time, but compared to heating from the back side of the recording medium M using a platen heater 4 or the like, the temperature can be increased without being affected by the thickness of the recording medium M. Also, various fans (for example, ventilation fan 8) may be provided to blow warm air or air at the same temperature as the environment onto the recording medium M to dry the ink on the recording medium M.

[0186] The platen heater 4 is capable of heating the recording medium M via the platen 11 at a position facing the inkjet head 2 so that the treatment liquid and inkjet ink composition ejected by the inkjet head 2 can be dried quickly from the moment they are applied to the recording medium M. The platen heater 4 is capable of conducting heat to the recording medium M, and in the recording method of this embodiment, the inkjet ink composition can be applied to the heated recording medium M. This allows the inkjet ink composition to be fixed quickly on the recording medium M, improving image quality.

[0187] The heater 5 dries and solidifies the treatment liquid or inkjet ink composition applied to the recording medium M, i.e., it is a heater for secondary heating or secondary drying. The heater 5 can be used in a post-drying process. When the heater 5 heats the recording medium M on which an image has been recorded, the moisture and other components contained in the inkjet ink composition evaporate and dissipate more quickly, and an ink film is formed by the resin that may be contained in the inkjet ink composition. In this way, the ink film is firmly fixed or adhered to the recording medium M, providing excellent film-forming properties, and an excellent, high-quality image can be obtained in a short period of time.

[0188] The inkjet recording apparatus 1 may have a cooling fan 6. After the inkjet ink composition recorded on the recording medium M has dried, the inkjet ink composition on the recording medium M is cooled by the cooling fan 6, thereby forming an ink coating film on the recording medium M with good adhesion.

[0189] The inkjet recording apparatus 1 may also include a preheater 7 that preheats the recording medium M before the inkjet ink composition is applied to the recording medium M. Furthermore, the inkjet recording apparatus 1 may also include a ventilation fan 8 so that the inkjet ink composition applied to the recording medium M can dry more efficiently.

[0190] Below the carriage 9, there are provided a platen 11 that supports the recording medium M, a carriage movement mechanism 13 that moves the carriage 9 relative to the recording medium M, and a conveying means 14 that is a roller that conveys the recording medium M in the sub-scanning direction. The operations of the carriage movement mechanism 13 and the conveying means 14 are controlled by a control unit CONT.

[0191] 1 and 2, a serial type inkjet recording device is shown, but a line type inkjet recording device can also be used. The inkjet recording apparatus exemplified above can be preferably used to implement the recording method according to this embodiment.

[0192] 2.6.Effects According to this recording method, a treatment liquid containing an organic acid and one or more selected from an organic acid polyvalent metal salt and a cationic polymer is used, which results in good aggregation ability and good drying properties, and makes it possible to improve the image quality and abrasion resistance of images formed using an aqueous inkjet ink composition containing a colorant.

[0193] 3. Examples and Comparative Examples The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" below is based on mass.

[0194] 3.1. Preparation of treatment solution The components were placed in a container to obtain the compositions shown in Tables 1 to 4 below, mixed and stirred for 2 hours using a magnetic stirrer, and then filtered through a membrane filter with a pore size of 5 μm to obtain the treatment solutions used in the Examples and Comparative Examples. All values ​​in Tables 1 to 4 below indicate mass %, and pure water was added so that the total mass of the treatment solution became 100 mass %.

[0195] [Table 1]

[0196] [Table 2]

[0197] [Table 3]

[0198] [Table 4]

[0199] In Tables 1 to 4, "bp" indicates the normal boiling point. In Tables 1 to 4, the substances listed other than the compound names are as follows: Catiomaster PD-7: Amine-epichlorohydrin copolymer, manufactured by Yokkaichi Synthetic Co., Ltd. Lupasol FG: Polyethyleneimine, manufactured by BASF Japan Ltd. PG: Propylene glycol 1,3BG: 1,3-butylene glycol MB: 3-methoxy-1-butanol PM: Propylene glycol-1-monomethyl ether DPM: Dipropylene glycol monomethyl ether 2P: 2-pyrrolidone DMSO: Dimethyl sulfoxide EOXM: 3-ethyl-3-oxetanemethanol 1,2HD: 1,2-hexanediol CPL: ε-caprolactam BYK-349: Silicone surfactant, manufactured by BYK Japan Co., Ltd. Surfynol DF110D: Acetylenic surfactant, manufactured by Nissin Chemical Industry Co., Ltd.

[0200] 3.2. Preparation of Inkjet Ink Composition The following components were placed in a container, mixed and stirred for 2 hours using a magnetic stirrer, and then filtered through a membrane filter with a pore size of 5 μm to obtain inkjet ink compositions for the Examples and Comparative Examples. Pure water was added so that the total mass of the inkjet ink composition was 100% by mass. PG: 15.0% by mass 1,2HD: 1.0% by mass MB: 5.0% by mass TIPA (triisopropanolamine): 1.0% by mass CPL: 2.0% by mass BYK-349: 0.5% by mass Cyan pigment (active ingredient): 4.0% by mass Joncryl 631 (active ingredient): 6.0% by mass Hi-Tec E-6500 (active ingredient): 0.5% by mass The product names are as follows: JONCRYL 631: Styrene-acrylic resin emulsion, manufactured by BASF Japan Ltd. Hi-Tec E-6500: Polyethylene wax emulsion, manufactured by Toho Chemical Industry Co., Ltd.

[0201] A cyan pigment dispersion was prepared as follows. 50 g of methyl ethyl ketone (MEK) was added to a flask equipped with a dropping funnel, a nitrogen inlet, a reflux condenser, a thermometer, and a stirrer, and the mixture was heated to 75°C while bubbling with nitrogen. A mixture of monomers (80 g of butyl methacrylate, 50 g of methyl methacrylate, 15 g of styrene, and 20 g of methacrylic acid), 50 g of MEK, and 500 mg of a polymerization initiator (azobisisobutyronitrile / AIBN) was added dropwise from the dropping funnel over 3 hours.

[0202] After the dropwise addition, the mixture was heated under reflux for an additional 6 hours, allowed to cool, and the evaporated amount of MEK was added to obtain a resin solution (resin solids content 50% by mass, acid value 79 mg / KOH, Tg 65°C). A predetermined amount of 20% by mass aqueous sodium hydroxide solution was added as a neutralizing agent to 20 g of the solution to neutralize 100% of the salt-forming groups, and 50 g of pigment (CI Pigment Blue 15:3) was added little by little with stirring, followed by kneading for 2 hours in a bead mill.

[0203] 200 g of ion-exchanged water was added to the obtained kneaded product and stirred, and then the mixture was heated under reduced pressure to distill off MEK. The concentration was further adjusted with ion-exchanged water to obtain a pigment dispersion (pigment solid content 20 mass %, resin solid content 5 wt %).

[0204] 3.3.pH Measurement The pH of each treatment liquid was measured using a pH meter (HORIBA: F-74) and is shown in Tables 1 to 4. The pH of the ink was also measured using the same pH meter and was found to be 9.0. Tables 1 to 4 show the difference between the pH of each treatment liquid and the pH of the ink (treatment liquid pH - ink pH).

[0205] 3.4. Recording test The recording conditions in the evaluation test were as follows. [Recording conditions] Printing machine: "SC-R5050", manufactured by Seiko Epson Corporation Resolution: 1200 x 1200 dpi Ink deposition amount: Maximum 17mg / inch 2 (duty 100%) Amount of treatment liquid attached: 10.0% by mass of the amount of ink attached Printing pattern: Solid pattern (ink + processing liquid) Number of scans: 9 Paper surface temperature: 45℃ Post-drying temperature: 70°C. Post-heating was performed using a heater for the post-drying process installed downstream in the recording medium transport direction. Recording medium: "Orajet 3165G-010", product name of Orafol Japan, vinyl chloride film Platen gap: 1.7mm

[0206] The above recording conditions will now be explained in more detail. The paper surface temperature is the surface temperature of the recording medium during the primary drying process. A platen heater was used as the primary drying means. In addition, a fan installed above the inkjet head blew air near the surface of the recording medium. The air temperature was set to 25°C. The number of scans is the number of times main scans were performed in the same main scanning area. In the inkjet head of the above recording device, the nozzle row located on the upstream side in the recording medium transport direction was filled with treatment liquid, and the nozzle row located on the downstream side was filled with ink liquid. Recording was performed under the above recording conditions.

[0207] 3.5.Evaluation Method In each of the examples and comparative examples, evaluation tests were carried out on the abrasion resistance, image quality (wetting spread), clogging recovery, and storage stability. The methods used are described below.

[0208] 3.5.1. Evaluation of component reliability First, equal amounts of epoxy resin EPIKOTE RESIN 828 (manufactured by HEXION) and curing agent VERSAMID 125 (manufactured by GABRIEL) were mixed and cured to obtain a cured epoxy resin.

[0209] A 0.4 g piece of cured epoxy resin was completely immersed in a container containing the treatment solution, the lid was closed, and the container was left for 14 days in an environment at 60°C. After leaving the container, the cured resin was removed, thoroughly washed again from the treatment solution, and weighed. The swelling ratio of the cured resin was calculated using the following formula. Swelling rate (%) = ((weight after addition - weight before addition) / weight before addition) x 100

[0210] The swelling ratio of each of the prepared treatment solutions was measured and evaluated based on the following criteria. The results are shown in Tables 1 to 4. A: Swelling rate 30% or less B: Swelling rate more than 30% and less than 40% C: Swelling rate over 40%

[0211] 3.5.2.Abrasion resistance For each example and comparative example, a solid pattern (70% duty) was printed on a recording medium by inkjet printing using the treatment liquid and ink listed in Table 5. The solid pattern was then left to stand at room temperature for 30 minutes, and the solid pattern was cut into a 30 x 150 mm rectangle. The printed area was then wetted with water and rubbed 100 times with a plain woven cloth using a Gakushin abrasion resistance tester (load 500 g). The degree of ink peeling was evaluated visually. Evaluation was based on the following criteria, and the results are shown in Tables 5-1 to 5-4. AA: No peeling A: Less than 20% of the evaluation area is peeled off B: Less than 50% of the evaluation area is peeled off C: Peeling of more than 50% of the evaluation area

[0212] 3.5.3. Solid Image Quality For each example and comparative example, a solid pattern (a gradation pattern in 10% duty increments) was printed on a recording medium by inkjet printing using the treatment liquid and ink shown in Table 5, and the printout was visually observed. Evaluation was based on the following criteria, and the results are shown in Tables 5-1 to 5-4. AA: Good uniformity of solid A: Unevenness occurs in the middle area (duty 60%) and is visible at a distance of 30 cm. B: Unevenness occurs in the middle area (duty 60%) and is visible at a distance of 1m C: Unevenness occurs even in the high duty area (duty 90%) and is visible at a distance of 30 cm.

[0213] 3.5.4. Odor 5 g of each treatment solution was placed in a petri dish and heated at 45° C., and the odor was subjected to a sensory evaluation. The evaluation was based on the following criteria, and the results are shown in Tables 5-1 to 5-4. A: The odor is not a concern B: The odor is noticeable, but tolerable C: The odor is very bothersome and unpleasant.

[0214] [Table 5]

[0215] 3.6.Evaluation Results It was found that the treatment liquids of the Examples, which contained an organic acid and one or more selected from an organic acid polyvalent metal salt and a cationic polymer, in which the content of the one or more selected from the organic acid polyvalent metal salt and the cationic polymer was 1% by mass to 15% by mass relative to the total mass of the treatment liquid and had a pH of 5.5 or higher, all exhibited excellent image abrasion resistance and image quality. In contrast, the comparative examples, which did not exhibit this characteristic, all exhibited poor image abrasion resistance, image quality, or component reliability.

[0216] The above-described embodiment and modifications are merely examples, and the present invention is not limited to these. For example, the embodiments and modifications can be combined as appropriate.

[0217] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations that replace non-essential parts of the configurations described in the embodiments. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations that add publicly known technology to the configurations described in the embodiments.

[0218] The following can be derived from the above-described embodiment and modifications.

[0219] The processing liquid is An aqueous treatment liquid, The treatment liquid is used in a recording method in which a water-based ink-jet ink composition containing a coloring material and the treatment liquid are applied to a recording medium, Organic acids and and one or more selected from organic acid polyvalent metal salts and cationic polymers, the content of one or more selected from the organic acid polyvalent metal salt and the cationic polymer is 1% by mass or more and 15% by mass or less relative to the total mass of the treatment liquid, The pH is 5.5 or higher.

[0220] This treatment liquid contains at least one selected from organic acid polyvalent metal salts and cationic polymers, as well as an organic acid, and therefore exhibits good coagulation ability and drying properties for components of an aqueous inkjet ink composition containing a colorant. This allows the abrasion resistance and image quality of images formed using the inkjet ink composition to be improved. Furthermore, since the pH of this treatment liquid is not too low, component reliability can be ensured.

[0221] The pH of the treatment liquid may be lower than the pH of the inkjet ink composition by 1.5 or more.

[0222] This treatment liquid improves the aggregation ability of the components of the water-based ink-jet ink composition containing the coloring material, making it possible to obtain images with better quality.

[0223] In the treatment liquid, the organic acid is a divalent organic acid, and when the treatment liquid contains the organic acid polyvalent metal salt, the organic acid polyvalent metal salt may be a salt composed of a monovalent organic acid and a polyvalent metal.

[0224] This treatment liquid has better drying properties and can improve the abrasion resistance of the image.

[0225] In the treatment liquid, the content of the organic acid may be 2.5% by mass or less.

[0226] This treatment liquid makes it easy to prevent deterioration of the container members and the recording medium.

[0227] The treatment liquid may have a pH of 5.5 or more and 7.5 or less.

[0228] This treatment liquid makes it easy to prevent deterioration of the container members and the recording medium.

[0229] The treatment liquid may further contain a water-soluble low-molecular-weight organic compound.

[0230] This treatment liquid can further improve the drying properties of the image.

[0231] The treatment liquid may contain, as the water-soluble low-molecular-weight organic compound, an alkanediol having a standard boiling point of 210°C or less and an alkylene glycol monoether having a standard boiling point of 210°C or less and represented by the following general formula (1): [ka] (In formula (1), R 1 represents a hydrocarbon group having 2 to 5 carbon atoms, and R 2 represents a hydrocarbon group having 1 to 2 carbon atoms, and n represents 1 or 2.

[0232] This treatment liquid can further improve the drying properties of the image.

[0233] The treatment liquid may contain 30% by mass or less of a compound having a normal boiling point of 250° C. or less as the water-soluble low-molecular organic compound.

[0234] This treatment liquid can further improve the drying properties of the image.

[0235] In the treatment liquid, the water-soluble low-molecular organic compound may contain one or more compounds selected from amides, sulfur-containing compounds, and cyclic ethers, all of which have a normal boiling point of 150°C or higher and 300°C or lower.

[0236] This treatment liquid can further improve the drying properties of the image.

[0237] The above-mentioned treatment liquid may be used for recording on a non-absorbent recording medium or a low-absorbent recording medium.

[0238] This treatment liquid can more significantly improve the abrasion resistance and image quality of the image formed using the inkjet ink composition.

[0239] The treatment liquid may further contain a silicone surfactant in an amount of 0.1% by mass or more and 4% by mass or less relative to the total mass of the treatment liquid.

[0240] This treatment liquid has better permeability into the recording medium, and can produce better images.

[0241] The recording method includes a treatment liquid application step of applying the treatment liquid to the recording medium, and an ink application step of applying the inkjet ink composition to the recording medium by an inkjet method.

[0242] According to this recording method, a treatment liquid containing an organic acid and one or more selected from an organic acid polyvalent metal salt and a cationic polymer is used, which results in good aggregation ability and good drying properties, and makes it possible to improve the image quality and abrasion resistance of images formed using an aqueous inkjet ink composition containing a colorant. [Explanation of symbols]

[0243] 1...inkjet recording device, 2...inkjet head, 3...IR heater, 4...platen heater, 5...heating heater, 6...cooling fan, 7...preheater, 8...ventilation fan, 9...carriage, 11...platen, 12...cartridge, 13...carriage moving mechanism, 14...conveying means, CONT...control unit, MS...main scanning direction, SS...sub-scanning direction, M...recording medium

Claims

1. An aqueous treatment liquid, The treatment liquid is used in a recording method in which a water-based ink-jet ink composition containing a coloring material and the treatment liquid are applied to a recording medium, Organic acids and and an organic acid polyvalent metal salt, the content of the organic acid polyvalent metal salt is 1% by mass or more and 15% by mass or less relative to the total mass of the treatment liquid, the content of the organic acid is 1.0% by mass or less relative to the total mass of the treatment liquid, A treatment solution having a pH of 5.5 or higher.

2. In claim 1, The treatment liquid has a content of the organic acid polyvalent metal salt of 1% by mass or more and 5.0% by mass or less relative to the total mass of the treatment liquid.

3. In claim 1 or claim 2, the organic acid is a divalent organic acid, The organic acid polyvalent metal salt is a salt of a monovalent organic acid and a polyvalent metal.

4. In any one of claims 1 to 3, The treatment liquid has an organic acid content of 0.3% by mass or less.

5. In any one of claims 1 to 4, A treatment solution having a pH of 5.5 or more and 7.5 or less.

6. In any one of claims 1 to 5, The treatment solution further comprises a water-soluble low-molecular-weight organic compound.

7. In claim 6, The treatment liquid contains, as the water-soluble low-molecular-weight organic compound, an alkanediol having a standard boiling point of 210°C or less and an alkylene glycol monoether represented by the following general formula (1) having a standard boiling point of 210°C or less: 【Chemical 1】 (In formula (1), R1 represents a hydrocarbon group having 2 to 5 carbon atoms, R2 represents a hydrocarbon group having 1 to 2 carbon atoms, and n represents 1 or 2.)

8. In claim 6 or claim 7, The treatment liquid contains 30% by mass or less of a compound having a normal boiling point of 250° C. or less as the water-soluble low-molecular-weight organic compound.

9. In any one of claims 6 to 8, The water-soluble low-molecular organic compound in the treatment liquid contains at least one compound selected from the group consisting of amides, sulfur-containing compounds, and cyclic ethers, all of which have a normal boiling point of 150°C or higher and 300°C or lower.

10. In any one of claims 1 to 9, A processing liquid used for recording on non-absorbent or low-absorbent recording media.

11. In any one of claims 1 to 10, The treatment liquid further contains a silicone surfactant in an amount of 0.1% by mass or more and 4% by mass or less relative to the total mass of the treatment liquid.

12. a treatment liquid applying step of applying the treatment liquid according to any one of claims 1 to 11 to the recording medium; an ink deposition step of depositing the inkjet ink composition onto the recording medium by an inkjet method; A recording method comprising:

13. In claim 12, A recording method, wherein the pH of the treatment liquid is lower than the pH of the inkjet ink composition by 1.5 or more.

Images