Recording method and recording apparatus

Abstract

Provided are a recording method and a recording apparatus that improve image quality and are not susceptible to clogging. The recording method includes: a processing liquid attachment step of attaching a processing liquid containing a coagulant to a recording medium; an ink attachment step of ejecting an ink composition, which is a water-based ink composition containing a colorant, from an inkjet head and attaching the ink composition to a recording medium; a transport step of transporting the recording medium on which the previous step has been performed to a heating mechanism; and a heating step of heating the recording medium conveyed by the conveyance step by a heating mechanism, the ink adhesion step being performed on the recording medium supported by the recording medium support section, the recording medium support section having no device for heating the recording medium supported by the recording medium support section in a conduction manner. The heating mechanism has a portion located in a space extending from a region of the recording medium supported by the recording medium support portion to which the ink composition can adhere in an extension direction on the opposite side from the inkjet head, and the surface temperature of the recording medium is 27 DEG C or more and 38 DEG C or less.

Description

Technical Field

[0001] The present invention relates to a recording method and a recording device. Background Art

[0002] Inkjet recording methods are known for recording images on recording media by ejecting minute ink droplets from nozzles of an inkjet head of an inkjet recording device, and their use in, for example, signature printing, label printing, and package printing has been studied.

[0003] Patent Document 1 discloses a printing press that utilizes a drying process. The printing press described in Patent Document 1 performs a primary drying process to dry the ink adhered to the recording medium, followed by a secondary drying process. The secondary drying process is performed at a high heating temperature and downstream in the conveyance direction of the recording medium. Meanwhile, the primary drying process in Patent Document 1 is performed near the platen.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2011-056832

[0007] However, heating the recording medium can sometimes clog the nozzles of the recording head. On the other hand, not heating the recording medium can sometimes hinder early drying of the ink, resulting in insufficient image quality. Furthermore, heating the recording medium makes it impossible to simplify the recording device or save space. Summary of the Invention

[0008] One embodiment of the recording method according to the present invention includes:

[0009] a treatment liquid attachment step of attaching the treatment liquid containing the coagulant to the recording medium;

[0010] an ink adhesion step of causing the ink composition to be ejected from the inkjet head and adhere to the recording medium;

[0011] a conveying step of conveying the recording medium having undergone the treatment liquid adhering step and the ink adhering step to a heating mechanism; and

[0012] a heating step of heating the recording medium conveyed by the conveying step by using the heating mechanism;

[0013] The ink composition is a water-based ink composition containing a colorant,

[0014] The ink adhesion step is performed on the recording medium supported by the recording medium support portion.

[0015] The recording medium support portion does not have a device for conductively heating the recording medium supported by the recording medium support portion.

[0016] The heating mechanism includes a portion located in a space extending from a region of the recording medium supported by the recording medium support portion to which the ink composition can adhere in an extending direction opposite to the inkjet head.

[0017] The surface temperature of the recording medium supported by the recording medium supporting portion and subjected to the ink adhering step is 27° C. or higher and 38° C. or lower.

[0018] One embodiment of a recording device according to the present invention performs the above-mentioned recording method, and the recording device includes:

[0019] the treatment fluid;

[0020] the ink composition;

[0021] a treatment liquid attachment mechanism for performing the treatment liquid attachment process;

[0022] the inkjet head;

[0023] A conveying mechanism for carrying out the conveying process;

[0024] the heating mechanism; and

[0025] The recording medium supporting portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a front view schematically showing an example of a serial recording device.

[0027] Figure 2 It is a bottom view partially showing an example of the structure of an inkjet head.

[0028] Figure 3 This is a front view schematically showing another example of a serial recording device.

[0029] Figure 4 This is a front view schematically showing another example of a serial recording device.

[0030] Figure 5 It is a perspective view schematically showing another example of a serial recording device.

[0031] Figure 6 This is a table (Table 1) showing the formulations and the like of the compositions used in Examples and Comparative Examples.

[0032] Figure 7 This is a table (Table 2) showing the conditions and evaluation results of Examples.

[0033] Figure 8 The table (Table 3) shows the conditions and evaluation results of the examples.

[0034] Figure 9 The table (Table 4) shows the conditions and evaluation results of Examples and Comparative Examples.

[0035] Description of Reference Numerals

[0036] 1: Main body; 2: Delivery unit; 9: Slide frame; 12: Slide main body; 13: Slide moving mechanism; 14: Transport unit; 21: Delivery shaft; 3: Printing chamber; 30, 11: Platen; 31: Recording unit; 32: Slide; 33: Support plate; 34: Inkjet head for treatment liquid; 35: Inkjet head for ink; 37: X-axis guide; 38: Suction unit; 39: Heater; 4: Drying unit; 5: Roll Winding portion; 51: Winding shaft; 6: Base; 71-77: Rollers; 8: Box mounting portion; 81: Processing liquid box; 82: Ink cartridge; 100, 101, 102: Recording device; 200: Host device; 210: Printer driver; 230: Communication control unit; 240: Monitor; 300: Printer unit; 400: Printer control unit; R1, R2: Rolls; S: Sheet; A: Attachment area; D: Distance. DETAILED DESCRIPTION

[0037] Below, the embodiment of the present invention is described. The embodiment described below illustrates an example of the present invention. The present invention is not limited to any of the following embodiments, and also includes various modifications implemented within the scope of the present invention. In addition, the structures described below are not necessarily all necessary structures of the present invention.

[0038] 1. Recording method

[0039] The recording method involved in this embodiment includes: a treatment liquid adhesion process, in which a treatment liquid containing a coagulant is adhered to a recording medium; an ink adhesion process, in which an ink composition is ejected from an inkjet head and adhered to a recording medium; a conveying process, in which the recording medium that has undergone the treatment liquid adhesion process and the ink adhesion process is conveyed to a heating mechanism; and a heating process, in which the recording medium conveyed through the conveying process is heated by the heating mechanism.

[0040] 1.1. Recording Media

[0041] The recording medium used in the recording method according to this embodiment is not particularly limited, and examples thereof include absorptive recording media, low-absorptive recording media, and non-absorptive recording media. Among these, low-absorptive recording media and non-absorptive recording media are preferred, with non-absorptive recording media being more preferred. Non-absorptive recording media have particularly poor filling properties, and therefore are useful in the present invention.

[0042] Here, the terms "low-absorption recording medium" and "non-absorption recording medium" refer to recording media having a water absorption of 10 mL / m2 from the start of contact to 30 msec according to the Bristow method. 2 The following recording media. The Bristow method is the most popular method for measuring liquid absorption over a short period of time and is also adopted by the Japan Pulp and Paper Technology Association (JAPAN TAPPI). Details of the test method are described in "JAPAN TAPPI Pulp Test Methods 2000 Edition," Standard No. 51, "Paper and Board - Liquid Absorbency Test Method - Bristow Method."

[0043] Furthermore, non-absorbent or low-absorbent recording media can also be classified based on the wettability of the recording surface to water. For example, a 0.5 μL water droplet is placed on the recording surface of the recording medium and the rate of decrease in the contact angle is measured (comparison of the contact angle 0.5 milliseconds after impact with the contact angle 5 seconds after impact). This allows the recording medium to be characterized. More specifically, non-absorbent, as a property of the recording medium, means a decrease rate of less than 1%, low-absorbent means a decrease rate of at least 1% and less than 5%, and absorptive means a decrease rate of at least 5%. Contact angles can be measured using a portable contact angle meter, such as the PCA-1 (manufactured by Kyowa Interface Science Co., Ltd.).

[0044] The absorptive recording medium is not particularly limited, and examples thereof include plain paper such as electrophotographic paper having high permeability to the ink composition, inkjet paper (inkjet paper having an ink-absorbing layer composed of silica particles or alumina particles, or an ink-absorbing layer composed of a hydrophilic polymer such as polyvinyl alcohol (PVA) or polyvinyl pyrrolidone (PVP), and art paper, coated paper, and cast-coated paper generally used for offset printing having low permeability to the ink composition.

[0045] The low-absorption recording medium is not particularly limited, and examples thereof include coated paper having a coating layer for receiving oil-based ink on the surface. The coated paper is not particularly limited, and examples thereof include printing papers such as art paper, coated paper, and matte paper.

[0046] The non-absorbent recording medium is not particularly limited, and examples thereof include recording media in which a plastic film or paper substrate having no ink-absorbing layer is coated with a plastic, or recording media in which a plastic film is adhered. Examples of the plastic herein include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0047] The recording medium may be in any shape as long as it can be conveyed in the conveying step, and may be, for example, a long strip wound up in a roll or the like, or a single sheet such as A4 size.

[0048] 1.2. Treatment liquid adhesion process

[0049] In the treatment liquid adhesion step, the treatment liquid containing the aggregating agent is adhered to the recording medium. The treatment liquid adhesion step can be performed simultaneously with the ink adhesion step, or before or after the ink adhesion step.

[0050] Examples of methods for applying the treatment liquid include dip coating in which the recording medium is immersed in the treatment liquid, roll coating in which the treatment liquid is applied using a brush, roller, blade, or roll coater, spray coating in which the treatment liquid is sprayed using a spray device, and inkjet coating in which the treatment liquid is applied using an inkjet method. Among these, the inkjet method is preferred.

[0051] 1.2.1. Treatment fluid

[0052] The processing liquid used in the recording method according to the present embodiment is an aqueous processing liquid containing a coagulant.

[0053] 1.2.1. (1) Coagulant

[0054] The treatment liquid contains a coagulant that causes the components of the ink composition to clump together. The coagulant reacts with components such as the colorant contained in the ink and the resin particles that may be contained in the ink, thereby causing the colorant and resin particles to clump together. However, the degree of aggregation of the colorant and resin particles produced by the coagulant varies depending on the type of coagulant, colorant, and resin particles, and can be adjusted. Furthermore, the coagulant reacts with the colorant and resin particles in the ink, causing them to clump together. This aggregation can, for example, enhance the color development of the colorant, improve the fixability of the resin particles, and / or increase the viscosity of the ink.

[0055] The coagulant is not particularly limited, and examples thereof include metal salts, inorganic acids, organic acids, and cationic compounds. Cationic compounds include cationic resins (cationic polymers) and cationic surfactants. Among these, polyvalent metal salts are preferred as metal salts, and cationic resins are preferred as cationic compounds. Therefore, from the perspective of achieving particularly excellent image quality, abrasion resistance, and gloss, the coagulant is preferably selected from cationic resins, organic acids, and polyvalent metal salts.

[0056] Metal salts are preferably polyvalent metal salts, but metal salts other than polyvalent metal salts may also be used. Among these coagulants, at least one selected from metal salts and organic acids is preferably used due to their excellent reactivity with components contained in the ink. Furthermore, among cationic compounds, cationic resins are preferably used due to their ease of solubility in the treatment liquid. Furthermore, multiple coagulants may be used in combination.

[0057] Polyvalent metal salts are compounds composed of metal ions with a valence of two or more and anions. Examples of metal ions with a valence of two or more include ions of calcium, magnesium, copper, nickel, zinc, barium, aluminum, titanium, strontium, chromium, cobalt, and iron. Among the metal ions that constitute these polyvalent metal salts, at least one of calcium and magnesium ions is preferred from the perspective of excellent cohesion of the ink components.

[0058] Anions constituting the polyvalent metal salt are inorganic ions or organic ions. Specifically, the polyvalent metal salt of the present invention is composed of inorganic or organic ions and a polyvalent metal. Examples of such inorganic ions include chloride ions, bromide ions, iodide ions, nitrate ions, sulfate ions, and hydroxide ions. Examples of organic ions include organic acid ions, such as carboxylic acid ions.

[0059] The polyvalent metal compound is preferably an ionic polyvalent metal salt. In particular, magnesium salts and calcium salts are preferred, as they provide improved stability in the treatment solution. Calcium salts are particularly preferred. Furthermore, the counter ion of the polyvalent metal may be either an inorganic acid ion or an organic acid ion.

[0060] Specific examples of the polyvalent metal salts include calcium carbonate such as heavy calcium carbonate and light calcium carbonate, calcium nitrate, calcium chloride, calcium sulfate, magnesium sulfate, calcium hydroxide, magnesium chloride, magnesium carbonate, barium sulfate, barium chloride, zinc carbonate, zinc sulfide, aluminum silicate, calcium silicate, magnesium silicate, copper nitrate, calcium formate, calcium acetate, magnesium acetate, aluminum acetate, and the like. One of these polyvalent metal salts may be used alone, or two or more may be used in combination. Of these, at least one of calcium formate, magnesium sulfate, calcium nitrate, and calcium chloride is preferred, with calcium formate and calcium nitrate being more preferred, as they can ensure sufficient solubility in water and reduce residual traces caused by the treatment solution (making the traces less noticeable). Furthermore, these metal salts may also contain water of hydration in their raw material form.

[0061] Examples of metal salts other than polyvalent metal salts include monovalent metal salts such as sodium salts and potassium salts, and examples thereof include sodium sulfate and potassium sulfate.

[0062] As the organic acid, for example, preferably poly (meth) acrylic acid, acetic acid, glycolic acid, malonic acid, malic acid, maleic acid, ascorbic acid, succinic acid, glutaric acid, fumaric acid, citric acid, tartaric acid, lactic acid, sulfonic acid, orthophosphoric acid, pyrrolidonecarboxylic acid, pyranonecarboxylic acid, pyrrolecarboxylic acid, furancarboxylic acid, pyridinecarboxylic acid, coumaric acid, thiophenecarboxylic acid, nicotinic acid or derivatives of their compounds or their salts etc. can be used alone or in combination of two or more. The substance as the metal salt in the salt of the organic acid is included in the above-mentioned metal salt.

[0063] Examples of the inorganic acid include sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, etc. The inorganic acid may be used alone or in combination of two or more.

[0064] Examples of the cationic resin (cationic polymer) include cationic polyurethane resins, cationic olefin resins, and cationic amine resins. The cationic polymer is preferably water-soluble.

[0065] As the cationic polyurethane resin, commercially available products can be used, for example, Hydran CP-7010, CP-7020, CP-7030, CP-7040, CP-7050, CP-7060, CP-7610 (trade names, manufactured by Dainippon Ink & Chemicals Co., Ltd.), Superflex 600, 610, 620, 630, 640, 650 (trade names, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), polyurethane emulsions WBR-2120C and WBR-2122C (trade names, manufactured by Daisei Fine Chemicals Co., Ltd.), etc.

[0066] Cationic olefin resins are resins containing an olefin such as ethylene or propylene in their structural backbone. Known resins can be appropriately selected and used. Furthermore, the cationic olefin resins may be in an emulsion state dispersed in a solvent such as water or an organic solvent. Commercially available cationic olefin resins can be used, for example, ArrowBase CB-1200 and CD-1200 (trade names, manufactured by Unitika Co., Ltd.).

[0067] As cationic amine resins (cationic polymers), any resin having amino groups in its structure can be used, and any known amine resin can be appropriately selected. Examples include polyamine resins, polyamide resins, and polyallylamine resins. Polyamine resins are resins having amino groups in their main backbone. Polyamide resins are resins having amide groups in their main backbone. Polyallylamine resins are resins having structures derived from allyl groups in their main backbone.

[0068] Examples of cationic polyamine resins include Unisense KHE103L (hexamethylenediamine / epichlorohydrin resin, a 1% aqueous solution having 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, a 1% aqueous solution having a pH of approximately 7.0, a viscosity of 1 to 10 (mPa·s), and a solids concentration of 20% by mass) manufactured by Senka Corporation. Furthermore, specific examples of commercially available cationic polyamine resins include FL-14 (manufactured by SNF), Arafix 100, 251S, 255, 255LOX (manufactured by Arakawa Chemical Co., Ltd.), DK-6810, 6853, 6885; WS-4010, 4011, 4020, 4024, 4027, 4030 (manufactured by Seiko PMC Co., Ltd.), Papiogen P-105 (manufactured by Senka Co., Ltd.), SumirezResin 650 (30), 675A, 6615, SLX-1 (manufactured by Taoka Chemical Industry Co., Ltd.), CatioMaster (registered trademark) PD-1, 7, 30, A, PDT-2, PE-10, PE-30, DT-EH, EPA-SK01, TMHMDA-E (manufactured by Yokkaichi Synthetic Co., Ltd.), JetFix 36N, 38A, 5052 (manufactured by Satoda Chemical Co., Ltd.).

[0069] Examples of the polyamine resin include polyallylamine resins, such as polyallylamine hydrochloride, polyallylamine amide sulfate, 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 amide sulfate, polymethyldiallylamine acetate, polydiallyldimethylammonium chloride, diallylamine acetate / sulfur dioxide copolymer, diallylmethylethylammonium sulfate / sulfur dioxide copolymer, methyldiallylamine hydrochloride / sulfur dioxide copolymer, diallyldimethylammonium chloride / sulfur dioxide copolymer, and diallyldimethylammonium chloride / acrylamide copolymer.

[0070] Multiple types of these coagulants may be used. Furthermore, if at least one of these coagulants is selected from a polyvalent metal salt, an organic acid, or a cationic resin, the coagulant effect is enhanced, thereby enabling the formation of higher-quality images (particularly with excellent color rendering). Furthermore, polyvalent metal salts are more preferably used as the coagulant, and calcium salts are even more preferably used. This further improves the quality of the resulting image.

[0071] The total amount of coagulant in the treatment liquid is, for example, 0.1% to 20% by mass relative to the total mass of the treatment liquid, preferably 1% to 20% by mass, and more preferably 2% to 15% by mass. Furthermore, even when a coagulant is present in a solution or dispersion, its solid content is preferably within the above-mentioned range. When the coagulant content is above the above-mentioned range, the coagulant's ability to agglomerate the components of the ink is fully achieved. Furthermore, when the coagulant content is below the above-mentioned range, the solubility and dispersibility of the coagulant in the treatment liquid are further improved, thereby enhancing the storage stability of the treatment liquid.

[0072] 1.2.1. (2) Water

[0073] The processing liquid used in the recording method of this embodiment may also be an aqueous processing liquid containing water. Aqueous refers to a composition containing water as one of the main solvent components. This allows for recording with less odor and reduced environmental impact.

[0074] Water can be included as the main solvent component of the treatment liquid and is a component that evaporates and disperses upon drying. The water is preferably pure water such as ion-exchanged water, ultrafiltered water, reverse osmosis water, or distilled water, or ultrapure water from which ionic impurities have been removed as much as possible. Furthermore, sterilizing the water by ultraviolet irradiation or by adding hydrogen peroxide is preferred because it can inhibit the growth of mold and bacteria during long-term storage of the ink. The water content is preferably 45% by mass or greater relative to the total amount of the treatment liquid. The upper limit is, for example, 99% by mass or less. It is preferably 50% by mass or greater and 98% by mass or less, and more preferably 55% by mass or greater and 95% by mass or less.

[0075] 1.2.1. (3) Surfactants

[0076] The processing liquid used in the recording method of this embodiment may also contain a surfactant. The surfactant is not particularly limited, and examples thereof include acetylene glycol surfactants, fluorine-based surfactants, and silicone-based surfactants. Surfactants have the function of adjusting the surface tension of the processing liquid, for example, adjusting wettability with the recording medium.

[0077] The acetylene glycol surfactant is not particularly limited, and 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 Japan Co., Ltd.), Olfin 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 are trade names, manufactured by Nissin Chemical Industry Co., Ltd.), Acetylenol E00, E00P, E40, E100 (all are trade names, manufactured by Kawaken Fine Chemical Co., Ltd.).

[0078] As the fluorine-based surfactant, a fluorine-modified polymer is preferably used, and a specific example thereof is BYK-340 (trade name, manufactured by BYK-Chemie Japan Ltd.).

[0079] The silicone surfactant is not particularly limited, but preferably includes polysiloxane compounds. The polysiloxane compound is not particularly limited, but examples thereof include polyether-modified organosiloxanes. Examples of commercially available products of the polyether-modified organosiloxane include BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, and BYK-348 (trade names, manufactured by BYK Chemicals Japan Ltd.), KF-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 (trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), Silface SAG503A, and Silface SAG014 (trade name, manufactured by Nissin Chemical Industry Co., Ltd.) and the like.

[0080] The surfactants may be used alone or in combination of two or more. When the surfactant is contained, the total content thereof is preferably 0.1% by mass or more and 1.5% by mass or less relative to the total mass of the inkjet ink composition.

[0081] 1.2.1. (4) Other ingredients

[0082] As long as the function is not impaired, the treatment liquid may contain resin particles, organic solvents, surfactants, waxes, additives, preservatives / antifungals, rust inhibitors, chelating agents, viscosity modifiers, antioxidants, antifungals, and other components.

[0083] (resin particles)

[0084] The treatment liquid may also contain resin particles. Resin particles can sometimes further improve the adhesion of the image formed by the ink attached to the recording medium. Examples of resin particles include resin particles formed from polyurethane resins, acrylic resins (including styrene acrylic resins), fluorene resins, polyolefin resins, rosin-modified resins, terpene resins, polyester resins, polyamide resins, epoxy resins, vinyl chloride resins, vinyl chloride-vinyl acetate copolymers, and ethylene vinyl acetate resins. Among them, polyurethane resins, acrylic resins, polyolefin resins, and polyester resins are preferred. These resin particles are mostly treated in the form of emulsions, but may also be in the form of powders. In addition, resin particles may be used alone or in combination of two or more.

[0085] The glass transition temperature (Tg) of the resin particles is preferably from -50°C to 200°C, more preferably from 0°C to 150°C, and even more preferably from 50°C to 100°C. Furthermore, it is particularly preferably from 50°C to 80°C. When the glass transition temperature (Tg) of the resin particles is within this range, durability and clogging resistance tend to be superior. The glass transition temperature can be measured, for example, using a differential scanning calorimeter (DSC7000) manufactured by Hitachi High-Technologies Corporation, in accordance with JIS K7121 (Determination of Transition Temperature of Plastics).

[0086] The volume average particle size of the resin particles is preferably 10 nm to 300 nm, more preferably 30 nm to 300 nm, further preferably 30 nm to 250 nm, and particularly preferably 40 nm to 220 nm. The volume average particle size can be measured by the above method.

[0087] The acid value of the resin in the resin particles is preferably 50 mgKOH / g or less, more preferably 30 mgKOH / g or less, even more preferably 20 mgKOH / g or less, and particularly preferably 10 mgKOH / g or less. Furthermore, the lower limit of the acid value is 0 mgKOH / g or more, preferably 5 mgKOH / g or more, and more preferably 10 mgKOH / g or more. Furthermore, it is preferably 15 mgKOH / g or more. This is preferred because it provides excellent image quality. Furthermore, when the acid value of the resin particles contained in the ink is above the above range, it is easier to achieve a viscosity increase ratio of the ink composition described below within the range described below. The acid value can be measured by the above-mentioned method.

[0088] The content of the resin particles in the treatment liquid is preferably 20% by mass or less, more preferably 10% by mass or less, even more preferably 5% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.1% by mass or less, based on the total mass of the treatment liquid, in terms of solid content. The content of the resin particles may be omitted. On the other hand, if present, the content is preferably 0.1% by mass or more, more preferably 1% by mass or more, and even more preferably 2% by mass or more.

[0089] The content of the resin particles in the ink, as a solids content, is preferably 0.5% by mass or greater, more preferably 1% by mass or greater, and even more preferably 3% by mass or greater, relative to the total mass of the ink. Furthermore, it is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less.

[0090] (Organic solvent)

[0091] The processing liquid used in the recording method of this embodiment may also contain an organic solvent. The organic solvent is preferably water-soluble. One function of the organic solvent is to increase the wettability of the processing liquid on the recording medium and improve the moisture retention of the processing liquid. Furthermore, the organic solvent can also function as a humectant and penetrant.

[0092] Examples of organic solvents include esters, alkylene glycol ethers, cyclic esters, nitrogen-containing solvents, and polyols. Examples of nitrogen-containing solvents include cyclic amides and non-cyclic amides. Examples of non-cyclic amides include alkoxyalkylamides.

[0093] Examples of the esters include glycol monoacetates such as ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether acetate; and glycol diesters such as ethylene glycol diacetate, diethylene glycol diacetate, and propylene glycol diacetate.

[0094] The alkylene glycol ethers may be any monoether or diether of an alkylene glycol, with alkyl ethers being preferred. Specific examples include alkylene glycol monoalkyl ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, and diethylene glycol monomethyl ether; and alkylene glycol dialkyl ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether.

[0095] Examples of the cyclic esters include cyclic esters (lactones) such as β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, and β-butyrolactone, and compounds in which the hydrogen atoms of the methylene groups adjacent to the carbonyl groups thereof are substituted with alkyl groups having 1 to 4 carbon atoms.

[0096] Examples of the alkoxyalkylamides 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, and 3-n-butoxy-N,N-methylethylpropionamide.

[0097] Examples of cyclic amides include lactams, such as pyrrolidones such as 2-pyrrolidone, 1-methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1-propyl-2-pyrrolidone, and 1-butyl-2-pyrrolidone. These are preferred from the viewpoint of the solubility of the coagulant and the promotion of film formation of the resin particles described later, and 2-pyrrolidone is particularly more preferred.

[0098] Furthermore, as the alkoxyalkylamides, compounds represented by the following general formula (1) are also preferably used.

[0099] R 1 -O-CH2CH2-(C=O)-NR 2 R 3 …(1)

[0100] In the above formula (1), R 1 represents an alkyl group having 1 to 4 carbon atoms, R 2 and R 3 Each independently represents a methyl group or an ethyl group. The "alkyl group having 1 to 4 carbon atoms" may be a linear or branched alkyl group, and may be, for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, or a tert-butyl group. The compound represented by the above formula (1) may be used alone or in combination of two or more.

[0101] One example of a nitrogen-containing solvent's function is to improve the surface drying and fixing properties of the treatment liquid attached to the low-absorbency recording medium. In particular, the compound represented by formula (1) is excellent at moderately softening and dissolving vinyl chloride resins. Therefore, the compound represented by formula (1) can soften and dissolve the recording surface containing vinyl chloride resin, allowing the treatment liquid to penetrate into the low-absorbency recording medium. As the treatment liquid penetrates the low-absorbency recording medium, the treatment liquid is firmly fixed, and the surface of the treatment liquid dries easily. Consequently, the resulting image is likely to have excellent surface drying and fixing properties.

[0102] When a nitrogen-containing solvent is used in the treatment liquid, its content is preferably no more than 15% by mass, more preferably no more than 10% by mass, and even more preferably no more than 5% by mass, relative to the total mass of the treatment liquid. Furthermore, it is preferably no more than 2% by mass, and even more preferably no more than 1% by mass.

[0103] In particular, it is preferred that the treatment liquid does not contain the aforementioned amide solvent, as this can further improve the granularity and abrasion resistance of the obtained image.

[0104] Examples of the polyol include 1,2-alkanediols (e.g., ethylene glycol, propylene glycol (also known as propane-1,2-diol), 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol, and other alkanediols), polyols other than 1,2-alkanediol (polyols) (e.g., diethylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol (also known as 1,3-butanediol), 1,2-butanediol, and the like). ,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-ethyl-2-methyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,3-butanediol, 2-ethyl-1,3-hexanediol, 3-methyl-1,5-pentanediol, 2-methylpentane-2,4-diol, trimethylolpropane, glycerol, etc.)

[0105] Examples of polyols include alkanediols and polyols. Alkanediols preferably have 5 or more carbon atoms. The number of carbon atoms in the alkane is preferably 5 to 10, more preferably 5 to 8, and even more preferably 5 to 6. Preferred are 1,2-alkanediol and propylene glycol. 1,2-alkanediol is preferred.

[0106] Examples of the polyols include alkanediols having 4 or less carbon atoms, intermolecular condensates between hydroxyl groups of alkanediols, and alkane polyols having triols or higher.

[0107] The alkane preferably has 2 to 3 carbon atoms. The number of hydroxyl groups in the polyol molecule is 2 or more, preferably 5 or less, and more preferably 3 or less. When the polyol is the above-mentioned intermolecular condensate, the number of intermolecular condensations is 2 or more, preferably 4 or less, and more preferably 3 or less. The polyols may be used alone or in combination of two or more.

[0108] Alkanediols and polyols can function mainly as penetrating solvents and / or moisturizing solvents. However, alkanediols tend to have stronger properties as penetrating solvents, while polyols tend to have stronger properties as moisturizing solvents.

[0109] The processing liquid may also contain a polyol-based organic solvent having a normal boiling point of 170°C to 240°C, which is preferred for further improving the graininess and abrasion resistance of the image. More preferably, the processing liquid contains a polyol-based organic solvent having a normal boiling point of 170°C to 240°C. This is more preferred in the aforementioned respects.

[0110] When the treatment liquid contains an organic solvent, one organic solvent may be used alone or two or more organic solvents may be used in combination. The total content of the organic solvents relative to the total mass of the treatment liquid is, for example, 1% by mass or more and 50% by mass or less.

[0111] Furthermore, it is preferably 5% by mass or more and 50% by mass or less, preferably 10% by mass or more and 45% by mass or less, more preferably 15% by mass or more and 40% by mass or less, and even more preferably 20% by mass or more and 40% by mass or less. Furthermore, it is preferably 25-35% by mass. When the content of the organic solvent is within the above range, the balance between wettability, spreadability and drying properties is further improved, making it easier to form high-quality images.

[0112] The content of the polyol organic solvent having a normal boiling point of 170°C to 240°C is preferably within the above range. Furthermore, the content of the polyol organic solvent having a normal boiling point of 170°C to 240°C is preferably within the above range.

[0113] The treatment liquid preferably does not contain 1% by mass or more of a polyol having a normal boiling point exceeding 280°C, and more preferably does not contain 0.5% by mass or more of a polyol having a normal boiling point exceeding 280°C. Furthermore, the content of an organic solvent other than polyols having a normal boiling point exceeding 280°C may be preferably within the above range.

[0114] (wax)

[0115] The treatment liquid may contain wax. Wax has the function of providing lubrication to the image formed by the ink, and thus may reduce the peeling of the image.

[0116] Examples of wax components that can be used alone or in combination include plant and animal waxes such as carnauba wax, candelilla wax, beeswax, rice bran wax, and lanolin; petroleum waxes such as paraffin wax, microcrystalline wax, polyethylene wax, oxidized polyethylene wax, and petrolatum; mineral waxes such as montan wax and ozokerite; synthetic waxes such as carbowax, Hoechst wax, polyolefin wax, and stearamide; and natural / synthetic wax emulsions and compounded waxes such as α-olefin / maleic anhydride copolymers. Polyolefin waxes (particularly polyethylene wax and polypropylene wax) and paraffin wax are preferred, as they enhance the fixing properties of the flexible packaging film described below.

[0117] As the wax, commercially available products may be used as they are, and examples thereof include Nopcote PEM-17 (trade name, manufactured by San Nopco Co., Ltd.), Chemipearl W4005 (trade name, manufactured by Mitsui Chemicals, Inc.), and AQUACER 515, 539, and 593 (these are trade names, manufactured by BYK Chemicals Japan Ltd.).

[0118] In addition, the recording method includes a heating step, etc., so from the viewpoint of suppressing excessive melting of the wax and its performance degradation, it is preferred to use a wax having a melting point of preferably 50°C to 200°C, more preferably 70°C to 180°C, and further preferably 90°C to 150°C.

[0119] The wax can be supplied in the form of an emulsion or suspension. The wax content, calculated as solids, relative to the total mass of the treatment liquid is preferably 0.1% to 10% by mass, more preferably 0.5% to 5% by mass, and even more preferably 0.5% to 2% by mass. When the wax content is within this range, the wax function can be effectively exerted. Furthermore, when the treatment liquid and at least one of the clear ink composition, ink composition, and ink composition described below contain wax, the lubrication function of the image can be more fully achieved.

[0120] (additive)

[0121] The treatment liquid may also contain additives such as ureas, amines, and sugars. Examples of ureas include urea, ethylene urea, tetramethyl urea, thiourea, and 1,3-dimethyl-2-imidazolidinone, as well as betaines (trimethylglycine, triethylglycine, tripropylglycine, triisopropylglycine, N,N,N-trimethylalanine, N,N,N-triethylalanine, N,N,N-triisopropylalanine, N,N,N-trimethylalanine, carnitine, and acetylcarnitine).

[0122] Examples of amines include diethanolamine, triethanolamine, and triisopropanolamine. Ureas and amines can also function as pH adjusters.

[0123] Examples of the sugars include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, aldonic acid, glucitol (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, and maltotriose.

[0124] (other)

[0125] The processing liquid used in the recording method according to the present embodiment may contain components such as an antiseptic / antifungal agent, a rust inhibitor, a chelating agent, a viscosity modifier, an antioxidant, and an antifungal agent as needed.

[0126] 1.2.1. (5) Physical properties of treatment fluid

[0127] From the perspective of ensuring optimal wetting and spreading properties on the recording medium, the surface tension of the treatment liquid used in the recording method of this embodiment at 25°C is 40 mN / m or less, preferably 38 mN / m or less, more preferably 35 mN / m or less, and even more preferably 30 mN / m or less. The surface tension can be measured by confirming the surface tension of a platinum plate wetted with the composition at 25°C using an automatic surface tensiometer CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).

[0128] The treatment liquid is more preferably applied to the recording medium by inkjet. In this case, the viscosity at 20°C is preferably 1.5 mPa·s to 15 mPa·s, more preferably 1.5 mPa·s to 7 mPa·s, and even more preferably 1.5 mPa·s to 5.5 mPa·s. When the treatment liquid is applied to the recording medium by inkjet, it is easy and efficient to form a predetermined treatment liquid application area on the recording medium.

[0129] 1.2.2. Method for attaching the treatment liquid to the recording medium

[0130] The treatment liquid attachment step can be performed by various methods such as roller coating, spraying, dipping, and inkjet. In particular, the inkjet method is preferred because the treatment liquid can be ejected from an inkjet head and attached to the recording medium, and the amount and position of attachment can be easily controlled.

[0131] In this case, for example, a method in which the treatment liquid is applied while the relative position of the inkjet head and the recording medium is moved, i.e., scanning, is performed can be used. Any method can also be used. Examples of inkjet methods include a serial method and a line method. This allows for efficient low-volume and high-volume printing using a compact device.

[0132] The amount of treatment liquid deposited in the treatment liquid depositing step is preferably 0.4 mg / inch 2More preferably, 0.5 mg / inch 2 Above, preferably 1.0 mg / inch 2 More than 1.5 mg / inch 2 More than, more preferably 2.0 mg / inch 2 In this way, an image with better filling properties can be obtained. In addition, the maximum amount of the treatment liquid attached in the treatment liquid attachment step can also be set to be above the above range, which is preferred.

[0133] In addition, the upper limit of the amount of treatment liquid deposited in the treatment liquid depositing step is preferably 5.0 mg / inch 2 Below. Furthermore, preferably 3.0 mg / inch 2 Below, further 2.5mg / inch 2 Below, more preferably 2.0 mg / inch 2 In particular, it is preferable that the maximum amount of the treatment liquid deposited in the treatment liquid depositing step be less than the above range.

[0134] If the adhesion amount is greater than the above range, the image is likely to be granular. However, in this case, the effect of the recording method of this embodiment that can suppress granularity is more significantly exhibited.

[0135] Furthermore, when the treatment liquid deposition step is performed using an inkjet method, the mass (ng) of the treatment liquid droplets is preferably 0.5 ng to 10 ng, more preferably 1 ng to 7 ng, even more preferably 1 ng to 5 ng, and even more preferably 2 ng to 4 ng. In terms of dot size (ng / dot), the mass (ng) of the treatment liquid droplets in the treatment liquid deposition step is preferably 0.5 ng / dot to 10 ng / dot, more preferably 1 ng / dot to 7 ng / dot, even more preferably 1 ng / dot to 5 ng / dot, and even more preferably 2 ng / dot to 4 ng / dot.

[0136] After the treatment liquid is deposited on the recording medium in the treatment liquid deposition step, the ink may be deposited on the recording medium in the ink deposition step. Furthermore, the treatment liquid deposition step may be performed by the same scan (pass) as that used to deposit the ink composition on the recording medium, depositing the treatment liquid on the same scanned area.

[0137] The treatment liquid adhering step is performed so that the ink composition adhering to the recording medium in the ink adhering step and the treatment liquid adhering to the recording medium in the treatment liquid adhering step can contact and react on the recording medium.

[0138] 1.3. Ink adhesion process

[0139] In the ink adhesion step, the ink composition is ejected from the inkjet head and adhered to the recording medium. The ink adhesion step is performed on the recording medium supported by the recording medium support. The surface temperature of the recording medium supported by the recording medium support and undergoing the ink adhesion step is 27°C to 38°C. The surface temperature is preferably 28°C to 35°C, and more preferably 29°C to 33°C. When the surface temperature is above this range, unevenness in light and dark colors is more effectively reduced. When the surface temperature is below this range, filling, pinhole suppression, clogging resistance, and condensation reduction are more effectively achieved.

[0140] The surface temperature of the recording medium undergoing the ink adhesion process is 27°C to 38°C due to heating by the heating mechanism, described later. Specifically, the recording medium support (platen), described later, does not include a device for conductively heating the recording medium supported by the recording medium support. Therefore, the surface temperature of the recording medium undergoing the ink adhesion process is maintained at 27°C to 38°C by the heat of the heating mechanism. In other words, the surface temperature of the recording medium undergoing the ink adhesion process is maintained at 27°C to 38°C due to residual heat from the heating mechanism. Details of the recording medium support will be described later.

[0141] 1.3.1. Ink composition

[0142] The ink composition used in the recording method of this embodiment may contain the following components.

[0143] 1.3.1. (1) Pigments

[0144] The ink composition may also contain a colorant. Examples of such colorants include dyes and pigments. Examples of such colorants include cyan, yellow, magenta, black, and other colorants, as well as white colorants. Furthermore, special color inks such as red, orange, blue, and green, as well as light inks such as light magenta, light cyan, and gray, may also be used.

[0145] The colorant may be any one of a dye and a pigment, or a mixture. However, among dyes and pigments, it is more preferred to include a pigment. The pigment has excellent storage stability such as light resistance, weather resistance, and gas resistance, and from this viewpoint, is preferably an organic pigment.

[0146] Specifically, the pigments used include azo pigments such as insoluble azo pigments, condensed azo pigments, azo lakes, and chelated azo pigments; polycyclic pigments such as phthalocyanine pigments, perylene pigments, peroxycyclic pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments; dye chelates, dye lakes, nitro pigments, nitroso pigments, aniline black, daylight fluorescent pigments, and carbon black. These pigments may be used alone or in combination of two or more. Furthermore, bright pigments may be used as colorants.

[0147] Specific examples of the pigment are not particularly limited, but include the following pigments.

[0148] Examples of the black pigment include No. 2300, No. 900, MCF88, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, and No. 2200B (all manufactured by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, and Raven 700 (all manufactured by Carbon Columbia), and Regal 400R, Regal 330R, and Regal 660R. Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, and Monarch 1400 (all manufactured by Cabot Corporation). JAPAN KK), Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, ColorBlack FW200, Color Black S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 (all manufactured by Degussa).

[0149] Examples of the yellow pigment include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 167, 172, and 180.

[0150] Examples of the magenta pigment include CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48 (Ca), 48 (Mn), 57 (Ca), 57:1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168, 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, and 245; and CI Pigment Violet 19, 23, 32, 33, 36, 38, 43, and 50.

[0151] Examples of the cyan pigment include CI Pigment Basket 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:34, 15:4, 16, 18, 22, 25, 60, 65, 66, and CI Vat Blue 4 and 60.

[0152] Pigments other than magenta, cyan, and yellow are not particularly limited, and examples thereof include CI Pigment Green 7 and 10, CI Pigment Brown 3, 5, 25, and 26, and CI Pigment Orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, and 63.

[0153] The pearlescent pigment is not particularly limited, and examples thereof include pigments having pearl luster or interference luster, such as titanium dioxide-coated mica, fish scale foil, and bismuth oxychloride.

[0154] The metallic pigment is not particularly limited, and examples thereof include particles composed of a single substance or an alloy of aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, copper, and the like.

[0155] As white coloring materials, for example, metal compounds such as metal oxides, barium sulfate, and calcium carbonate can be mentioned. As metal oxides, for example, titanium dioxide, zinc oxide, silicon dioxide, aluminum oxide, and magnesium oxide can be mentioned. In addition, particles having a hollow structure can be used as white coloring materials. As particles having a hollow structure, known particles can be used. As white coloring materials, titanium dioxide is preferably used from the viewpoint of good whiteness and abrasion resistance in the examples.

[0156] Examples of dyes that can be used include various dyes commonly used in inkjet recording, such as direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes, vat dyes, soluble vat dyes, and reactive disperse dyes.

[0157] The colorant is preferably capable of being stably dispersed or dissolved in the dispersion medium, and may be dispersed using a dispersant as needed.

[0158] The pigment is preferably stably dispersible in the dispersion medium, and thus a dispersant may be used to disperse it. Examples of dispersants include resin dispersants, which should be selected from those that provide good dispersion stability of the pigment in the ink composition. Furthermore, the pigment may be modified by surface oxidation or sulfonation with ozone, hypochlorous acid, fuming sulfuric acid, or the like, thereby forming a self-dispersible pigment.

[0159] Examples of the resin dispersant (dispersant resin) include (meth)acrylic acid resins and salts thereof, such as poly(meth)acrylic acid, (meth)acrylic acid-acrylonitrile copolymers, (meth)acrylic acid-(meth)acrylic ester copolymers, vinyl acetate-(meth)acrylic ester copolymers, vinyl acetate-(meth)acrylic acid copolymers, and vinylnaphthalene-(meth)acrylic acid copolymers; styrene resins and salts thereof, such as styrene-(meth)acrylic acid copolymers, styrene-(meth)acrylic acid-(meth)acrylic ester copolymers, styrene-α-methylstyrene-(meth)acrylic acid copolymers, styrene-α-methylstyrene-(meth)acrylic acid-(meth)acrylic ester copolymers, styrene-maleic acid copolymers, and styrene-maleic anhydride copolymers; polymer compounds (resins) containing urethane bonds formed by the reaction of isocyanate groups and hydroxyl groups, i.e., polyurethane resins that may be linear and / or branched and may or may not have a cross-linked structure, and salts thereof; polyvinyl alcohols; vinylnaphthalene-maleic acid copolymers and salts thereof; vinyl acetate-maleic acid ester copolymers and salts thereof; and water-soluble resins such as vinyl acetate-crotonic acid copolymers and salts thereof. Among them, copolymers of monomers having hydrophobic functional groups and monomers having hydrophilic functional groups, and polymers composed of monomers having both hydrophobic and hydrophilic functional groups are preferred. The copolymers may be random copolymers, block copolymers, alternating copolymers, or graft copolymers. Copolymers of styrene-based resins with (meth)acrylic acid monomers are also (meth)acrylic resins.

[0160] Examples of commercially available styrene-based resin dispersants include X-200, X-1, X-205, X-220, and X-228 (manufactured by Seikyo PMC Co., Ltd.), Nopco Sperse (registered trademark) 6100 and 6110 (manufactured by San Nopco Co., Ltd.), Joncryl 67, 586, 611, 678, 680, 682, and 819 (manufactured by BASF), DISPERBYK-190 (manufactured by BYK Chemicals Japan Ltd.), N-EA137, N-EA157, N-EA167, N-EA177, N-EA197D, N-EA207D, and E-EN10 (manufactured by Dai-ichi Kogyo Seiyaku).

[0161] Examples of commercially available acrylic resin dispersants include BYK-187, BYK-190, BYK-191, BYK-194N, and BYK-199 (manufactured by BYK-Chemie Co., Ltd.), and Aron A-210, A6114, AS-1100, AS-1800, A-30SL, A-7250, and CL-2 (manufactured by Toagosei Co., Ltd.).

[0162] Commercially available polyurethane resin dispersants include BYK-182, BYK-183, BYK-184, and BYK-185 (manufactured by BYK-Chemie Co., Ltd.), TEGO Disperse 710 (manufactured by Evonic Tego Chemie Co., Ltd.), and Borchi (registered trademark) Gen 1350 (manufactured by OMG Borschers).

[0163] Dispersant can be used alone or in combination with two or more.The content of the total of dispersant is preferably more than 0.1 mass part and below 30 mass parts relative to white colorant 50 mass parts, more preferably more than 0.5 mass part and below 25 mass parts, further preferably more than 1 mass part and below 20 mass parts, more further preferably more than 1.5 mass parts and below 15 mass parts.The content by dispersant is more than 0.1 mass part relative to colorant 50 mass parts, can further improve the dispersion stability of colorant.In addition, if the content of dispersant is below 30 mass parts relative to colorant 50 mass parts, then the viscosity of the dispersion obtained can be suppressed less.

[0164] Among the dispersants exemplified above, at least one selected from anionic dispersant resins is further preferred. In this case, the weight-average molecular weight of the dispersant is more preferably 500 or greater. Furthermore, it is preferably 5,000 or greater and 100,000 or less, and more preferably 10,000 or greater and 50,000 or less.

[0165] By using such a resin dispersant as a dispersant, the dispersion and aggregation of the pigment are improved, and better dispersion stability and a better quality image can be obtained. In addition, it is easy to increase the viscosity increase rate of the ink composition described below by 5 times or more, which is preferred.

[0166] Anionic dispersant resins are resins having anionic functional groups and exhibiting anionic properties. Examples of anionic functional groups include carboxyl groups, sulfo groups, and phosphoric acid groups. Of these groups, carboxyl groups are more preferred.

[0167] The dispersant resin may or may not have an acid value, but it preferably has one. The acid value is preferably 5 mgKOH / g or higher. Alternatively, the acid value is preferably 250 mgKOH / g or lower. Furthermore, the acid value is more preferably 10 to 200 mgKOH / g, and even more preferably 15 to 150 mgKOH / g. Furthermore, it is preferably 20 to 100 mgKOH / g, and even more preferably 30 to 80 mgKOH / g. Furthermore, the lower limit is preferably 40 mgKOH / g or higher, even more preferably 50 mgKOH / g or higher, particularly preferably 60 mgKOH / g or higher, and even more preferably 70 mgKOH / g or higher. Furthermore, it is preferably 80 mgKOH / g or higher.

[0168] When the acid value is equal to or greater than the above range, it is easy to increase the viscosity increase ratio of the ink composition, which will be described later, by 5 times or more, which is preferred.

[0169] The acid value can be measured by neutralization potentiometric titration in accordance with JIS K 0070. As a titration apparatus, for example, "AT610" manufactured by Kyoto Denshi Kogyo Co., Ltd. can be used.

[0170] The colorant content is preferably 0.3% to 20% by mass, more preferably 0.5% to 15% by mass, relative to the total mass of the ink composition. Furthermore, it is preferably 1% to 10% by mass, more preferably 2% to 7% by mass. For white ink, the above range is preferred, more preferably 5% to 17% by mass, and even more preferably 8% to 13% by mass.

[0171] The volume average particle diameter of the pigment particles under the situation of adopting pigment in colorant is preferably more than 10nm and below 300nm, more preferably more than 30nm and below 250nm, further preferably more than 50nm and below 250nm, particularly preferably more than 70nm and below 200nm.And then, be preferably more than 80nm and below 150nm.The volume average particle diameter of colorant is measured as initial state by the confirmation method of above-mentioned volume average particle diameter.When volume average particle diameter is above-mentioned scope, from the aspect that obtains desired colorant easily, make the good aspect such as characteristic of colorant, be preferred.

[0172] 1.3.1. (2) Water

[0173] The ink composition used in the recording method according to this embodiment is an aqueous ink containing water. Aqueous refers to a composition containing water as one of its main solvent components. This allows for recording with minimal odor and other environmental impacts. The water content and the water content used in the aforementioned treatment liquid can be the same, and further explanation is omitted.

[0174] 1.3.1. (3) Other ingredients

[0175] The ink composition may also contain components such as resin particles, an organic solvent, a surfactant, wax, additives, an antiseptic / antifungal agent, an antirust agent, a chelating agent, a viscosity modifier, an antioxidant, and an antifungal agent.

[0176] The components of the ink composition, excluding the colorant and aggregating agent, are the same as those used in the treatment liquid and can be selected independently of the treatment liquid. These components can be the same as those of the treatment liquid described above, and detailed descriptions thereof will be omitted by replacing "treatment liquid" with "ink composition."

[0177] When the ink composition contains an organic solvent, the organic solvent content is preferably, for example, 1% by mass or greater relative to the total mass of the ink composition. Furthermore, the organic solvent content is preferably 5% by mass or greater and 40% by mass or less, more preferably 10% by mass or greater and 35% by mass or less, and even more preferably 12% by mass or greater and 30% by mass or less. Furthermore, the organic solvent content is preferably 15% to 27% by mass, and even more preferably 20% to 25% by mass.

[0178] This makes it easier to achieve both reduced nozzle clogging and excellent image drying. When the ink composition contains an organic solvent, a concentration below the above range is preferred, as it accelerates reaction with the treatment liquid, significantly reduces unevenness in shading, improves ink drying properties, and enhances abrasion resistance. Furthermore, a concentration above the above range is more preferred, as it suppresses the reaction rate with the reaction liquid, improves filling properties, and significantly reduces pinholes.

[0179] Furthermore, when the content of the organic solvent is within the above range, it is easy to achieve a balance among image quality, filling, clogging, condensation, abrasion resistance, and ink drying properties.

[0180] 1.3.1. (4) Physical properties of ink composition

[0181] From the perspective of ensuring optimal wetting and spreading properties on the recording medium, the surface tension of the ink composition used in the recording method of this embodiment at 25°C is preferably 40 mN / m or less, preferably 38 mN / m or less, more preferably 35 mN / m or less, and even more preferably 30 mN / m or less. The surface tension is measured by measuring the surface tension of the composition when it wets a platinum plate at 25°C using an automatic surface tensiometer CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).

[0182] The ink composition is attached to the recording medium by an inkjet method. Therefore, the viscosity at 20°C is preferably 1.5 mPa·s to 15 mPa·s, more preferably 1.5 mPa·s to 7 mPa·s, and even more preferably 1.5 mPa·s to 5.5 mPa·s.

[0183] 1.3.2. Ink composition viscosity increase

[0184] The ink composition preferably exhibits a viscosity increase of five times or more when mixed with a 7% by mass aqueous solution of calcium formate at a mass ratio of 10:1 (ink composition:7% by mass aqueous solution of calcium formate). This viscosity-increasing property allows for sufficient cohesion of the components of the ink composition upon contact with the treatment liquid, resulting in improved image quality. This also further reduces unevenness in light and dark areas in the resulting image.

[0185] The viscosity increase rate of an ink composition is defined as follows: the increase in the ink's viscosity when mixed with a 7% by mass aqueous solution of calcium formate. Specifically, the viscosity increase rate refers to the ratio (multiplier) of the viscosity of the mixed solution after mixing and stirring the ink used in the recording method and the processing liquid at a mass ratio of 10:1, relative to the viscosity of the ink before mixing. Viscosity is measured at 20°C.

[0186] The viscosity increase ratio is the ratio of the viscosity after mixing to the viscosity before mixing. For example, the viscosity increase ratio is approximately 0.5 times or more and 10 times or less. Depending on the ink composition, the viscosity may decrease due to the viscosity increase ratio being less than 1.0 times, but this is still referred to as the viscosity increase ratio. Viscosity can be measured using a rheometer. When measuring viscosity, sample the mixed liquid after thoroughly stirring it.

[0187] The lower limit of the viscosity increase ratio of the ink composition is preferably 2 times or more, more preferably 3 times or more, even more preferably 5 times or more, even more preferably more than 5 times, even more preferably 5.5 times or more, even more preferably 6 times or more, and particularly preferably 7 times or more. Furthermore, it is preferably 10 times or more. This allows for the formation of images of higher quality.

[0188] On the other hand, the upper limit of the viscosity increase ratio of the ink composition is not limited, but is preferably 20 times or less, more preferably 10 times or less, even more preferably 9 times or less, even more preferably 8.5 times or less, and even more preferably 8 times or less. When the viscosity increase ratio of the ink composition is within the above range, image quality, crack resistance, abrasion resistance, ejection stability, etc. are further improved, which is preferred. Furthermore, the resulting image quality is excellent, and in particular, granularity can be reduced.

[0189] The viscosity increase rate of the ink composition can be adjusted mainly by adjusting the type and content of the pigment (including the resin dispersant) and the resin particles. In particular, adjusting the type and content of the pigment (including the resin dispersant) is easy and preferred.

[0190] 1.3.3. Method for Adhering the Ink Composition to the Recording Medium

[0191] The ink deposition process is performed by ejecting ink from an inkjet head and depositing it on a recording medium. This process is preferably performed by scanning, which moves the relative position of the inkjet head and the recording medium while depositing the ink composition, but it can be performed in any other manner. Examples of inkjet scanning include serial and line methods. This allows for efficient printing of small quantities and a variety of prints using a compact device.

[0192] The ink adhesion step can also cause multiple ink compositions to adhere to the recording medium. For example, the ink adhesion step can cause a non-white ink containing a non-white colorant and a white ink containing a white colorant to adhere to the recording medium. Furthermore, in this case, the number of non-white inks can be multiple. For example, the ink adhesion step can cause cyan, magenta, yellow, black, and white ink compositions to adhere to the recording medium.

[0193] The maximum amount of ink composition deposited in the ink depositing step is preferably 1.5 mg / inch 2 More preferably, 3.0 mg / inch 2 More than 4.0 mg / inch 2 More preferably, 5.0 mg / inch 2 In addition, it is preferably 25 mg / inch 2 Below, more preferably 20 mg / inch 2 Below, more preferably 15 mg / inch 2 the following.

[0194] Furthermore, it is preferably 11.0 mg / inch 2 Below, more preferably 10.0 mg / inch 2 Below. Further, more preferably 9.0 mg / inch 2 Below, more preferably 7.0 mg / inch 2 In this way, an image with better filling properties can be obtained. The above-mentioned adhesion amount is the total adhesion amount of the water-based ink containing the coloring material used for recording.

[0195] Furthermore, the mass (ng) of the ink composition droplets during the ink adhesion step is preferably 8 ng or less, more preferably 1 ng or more and 8 ng or less, even more preferably 1 ng or more and 7 ng or less, and even more preferably 2 ng or more and 6 ng or less. Regarding dot size (ng / dot), the mass (ng) of the ink composition droplets during the ink adhesion step is preferably 8 ng / dot or less, more preferably 1 ng / dot or more and 8 ng / dot or less, even more preferably 1 ng / dot or more and 7 ng / dot or less, and even more preferably 2 ng / dot or more and 6 ng / dot or less.

[0196] After the treatment liquid is deposited on the recording medium in the treatment liquid deposition step, the ink is deposited on the recording medium in the ink deposition step. Alternatively, the ink deposition step may be performed by depositing the ink composition on the same scan area as the scan pass used to deposit the treatment liquid on the recording medium.

[0197] 1.4. Conveying process

[0198] In the transport process, the recording medium after the treatment liquid adhesion process and the ink adhesion process is transported to the heating mechanism. The recording medium is transported by conventional means such as rollers and guides. The heating mechanism will be described later.

[0199] 1.5. Heating process

[0200] In the heating step, the recording medium conveyed in the conveying step is heated by a heating mechanism. The heating step can be performed, for example, using an appropriate heating unit (heating mechanism). The heating step is performed, for example, by a heater. This allows the resulting image to be dried and more fully fixed, thereby enabling, for example, the recorded material to be in a state ready for use sooner.

[0201] The temperature reached by the heating mechanism is not particularly limited and can be set, for example, in consideration of the Tg of the resin component constituting the resin particles contained in the recorded material. Taking into account the Tg of the resin components constituting the resin particles and wax, the temperature can be set to be 5.0°C or higher, preferably 10.0°C or higher, than the Tg of the resin component constituting the resin particles.

[0202] The surface temperature of the recording medium reached during the heating step is preferably 30.0°C to 120.0°C, more preferably 40.0°C to 100.0°C, even more preferably 50.0°C to 95°C, and even more preferably 70°C to 90°C. The surface temperature of the recording medium reached during the heating step is particularly preferably 80°C or higher. When the recording medium temperature is within this range, the resin particles and wax contained in the recorded material can be coated and flattened, allowing the resulting image to dry and be more fully fixed.

[0203] In the heating step, the recording medium is preferably heated by the heating mechanism for a period of time of 1 to 40 seconds, more preferably 3 to 25 seconds, and even more preferably 5 to 20 seconds. Furthermore, the period is preferably 9 to 15 seconds. This allows for high-speed formation of a fully dried image.

[0204] 1.6. Other processes

[0205] The recording method of this embodiment may include the following aspects and steps.

[0206] 1.6.1. Air supply process

[0207] During the ink adhesion process, an air blowing process may be performed. During the ink adhesion process, the ink composition adheres to the recording medium. However, the surface temperature of the recording medium at this time is between 27°C and 38°C. The air blowing process is performed so that the temperature does not deviate from this range. This allows the ink to be fixed more quickly, resulting in a higher-quality image.

[0208] The air supply step can be performed, for example, by using a fan or other means to supply room-temperature air or hot air to the recording medium. The air temperature during the air supply step is preferably adjusted so that the surface temperature of the recording medium is between 27°C and 38°C. It is particularly preferably below 40°C, more preferably below 38°C, more preferably below 35°C, and even more preferably below 30°C. Furthermore, it is preferably above 10°C, more preferably above 15°C, even more preferably above 20°C, and particularly preferably above 25°C. It may also be above 27°C.

[0209] The wind speed during the air supply process is preferably 1 m / s to 20 m / s, more preferably 2 m / s to 15 m / s, and even more preferably 3 m / s to 13 m / s. Furthermore, it is preferably 5 m / s to 10 m / s. This allows the ink to be fixed more quickly, resulting in a higher-quality image.

[0210] The wind speed refers to the wind speed near the recording medium (the distance between the recording medium and the head) and is the maximum wind speed in the area where recording can be performed on the recording medium on the platen. The wind temperature can be hot air, but is preferably room temperature. The wind temperature is also measured at the same location as the wind speed, without being affected by the heat of the platen.

[0211] 1.7. Recording Device

[0212] An example of a recording device that can be used in the recording method of this embodiment will be described. The recording device according to this embodiment is a recording device for performing the above-described recording method, and includes the treatment liquid, the ink composition, a treatment liquid attachment mechanism for performing the treatment liquid attachment step, the inkjet head, a transport mechanism for performing the transport step, the heating mechanism, and the recording medium support unit.

[0213] The heating mechanism of the recording apparatus of this embodiment has a portion located in a space extending from the ink composition adhered region of the recording medium supported by the recording medium support portion toward the side opposite to the inkjet head.

[0214] In the following examples, a recording apparatus is described in which the treatment liquid is discharged from an inkjet head and attached to a recording medium in the same manner as the ink attachment step.

[0215] In addition, the recording medium support portion, also called a platen, does not have a device for conductively heating the recording medium supported by the recording medium support portion. That is, the recording medium support portion does not have a component that serves as a heat source. In addition, "conductively" refers to a method of conducting heat by the movement of heat without the movement of matter. In addition, "conductively" heats the recording medium support portion by a heat source, and heat is conducted from the recording medium support portion to the recording medium supported by the recording medium support portion, thereby heating the recording medium. The heat source is integrally formed with the recording medium support portion. Moreover, heat is conducted from the heat source to the recording medium support portion, and heat is conducted from the recording medium support portion to the recording medium supported by the recording medium support portion. For example, it is a platen heater. The recording medium support portion of this embodiment does not have such a device for conductively heating the recording medium supported by the recording medium support portion.

[0216] If a device for conducting heat to the recording medium supported by the recording medium support is provided, simplification and space saving of the recording device cannot be achieved due to the need for a heat source, etc. In particular, such a device is integrally provided with the recording medium support and tends to occupy space below the recording medium support.

[0217] Furthermore, it is difficult to control the heating temperature of the recording medium to an appropriate level with such a device. Therefore, in this embodiment, by not including such a device, the recording device can be simplified and space-saving, and the heating temperature of the recording medium can be easily stabilized.

[0218] Figure 1 This is a front view schematically illustrating an example of a serial-type (serial method) recording device. The serial method performs scanning by ejecting ink from the inkjet head and depositing it onto the recording medium while the relative positions of the inkjet head and the recording medium are moved. The ink deposits onto the recording medium supported by a recording medium support, and recording is performed by performing multiple scans. For example, the inkjet head is mounted on a carriage, and scanning is performed by moving the carriage, which moves the inkjet head.

[0219] exist Figure 1 In this device, the carriage scanning direction and the recording medium conveyance direction are coaxial, resulting in a transverse recording device. In other words, the carriage scanning direction and the recording medium conveyance direction do not intersect. This device is a type of serial recording device.

[0220] In addition, Figure 1 In order to clarify the configuration relationship of each part of the device, the XYZ orthogonal coordinates with the Z axis as the vertical axis are also recorded. In addition, in the following description, the direction of each coordinate axis (arrow) is appropriately treated as the positive direction, and the opposite direction is appropriately treated as the negative direction. In addition, Figure 1The recording apparatus shown is a method in which the recording medium is transported in a direction along the axis of the scanning direction, and therefore is particularly also called a transverse recording apparatus.

[0221] The recording device 100 includes a host device 200 that generates print data based on image data (bitmap data) received from an external device such as a personal computer, and a printer unit 300 that prints an image based on the print data received from the host device 200. The printer unit 300 prints an image on the surface of a long sheet S using an inkjet method while conveying the sheet S in a roll-to-roll manner.

[0222] like Figure 1 As shown, the printer unit 300 includes a main body housing 1 having a generally rectangular parallelepiped shape. Disposed within the main body housing 1 are a feeder 2 for feeding sheets S from a roll R1 on which the sheets S are wound; a printing chamber 3 for ejecting ink onto the surface of the fed sheets S to perform printing; a drying unit 4 for drying the sheets S with ink attached; and a winding unit 5 for winding the dried sheets S into a roll R2.

[0223] More specifically, the main housing 1 is divided vertically along the Z-axis by a flat-plate base 6 arranged parallel to (i.e., horizontally) the XY plane. The upper side of the base 6 forms the print chamber 3. A platen 30 is fixed to the upper surface of the base 6 in the approximate center of the print chamber 3. The platen 30 has a rectangular shape and supports the sheet S from below with its upper surface parallel to the XY plane. Furthermore, a recording unit 31 prints on the surface of the sheet S supported by the platen 30.

[0224] On the other hand, the delivery unit 2, the drying unit 4, and the winding unit 5 are arranged on the lower side of the base 6. The delivery unit 2 is arranged on the lower side of the negative direction of the X axis relative to the platen 30 ( Figure 4 The sheet S is wound around the delivery shaft 21 and the roll R1 is supported. On the other hand, the winding section 5 is arranged on the lower side of the positive direction of the X axis relative to the pressure plate 30 ( Figure 1 The drying section 4 is located diagonally to the right and lower side of the platen 30. A rotatable winding shaft 51 is provided. The sheet S is wound around the winding shaft 51, supporting the roll R2. The drying section 4 is located directly below the platen 30, between the delivery section 2 and the winding section 5 in the X-axis direction.

[0225] The sheet S fed from the feed shaft 21 of the feed section 2 passes sequentially through the printing chamber 3 and the drying section 4 while being guided by rollers 71 to 77 before being wound onto the winding shaft 51 of the winding section 5. Furthermore, rollers 72 and 73 are arranged straight (i.e., horizontally) in the X-axis direction, sandwiching the platen 30 between them. Their positions are adjusted so that their tops are at the same height as the upper surface of the platen 30 (the surface supporting the sheet S). Therefore, the sheet S wound around roller 72 moves horizontally (in the X-axis direction) while in sliding contact with the upper surface of the platen 30 until it reaches roller 73.

[0226] In the printing chamber 3, a printing process is performed on a sheet S as a recording medium by a recording unit 31 arranged on the upper side of a platen 30. The recording unit 31 prints an image on the surface of the sheet S by ejecting a processing liquid and an ink composition onto the surface of the sheet S. Here, at the end portion ( Figure 1 A cartridge mounting portion 8 is provided at the left end portion of the sheet S. A treatment liquid cartridge 81 storing the treatment liquid and a plurality of ink cartridges 82 storing the ink composition are detachably mounted on the cartridge mounting portion 8. The recording unit 31 can eject the treatment liquid supplied from the treatment liquid cartridge 81 and the ink composition supplied from the ink cartridge 82 onto the surface of the sheet S by an inkjet method.

[0227] Figure 2 This is a bottom view partially showing the structure of the recording unit. In this example, Figure 1 as well as Figure 2 The recording unit 31 will now be described in detail. The recording unit 31 includes a carriage 32, a flat support plate 33 mounted on the bottom surface of the carriage 32, and a treatment liquid inkjet head 34 and an inkjet head 35 mounted on the bottom surface of the support plate 33. Four inkjet heads 35 and one treatment liquid inkjet head 34 are arranged at equal intervals in the X-axis direction on the bottom surface of the support plate 33. In each inkjet head 34 and 35, multiple nozzles N (nozzle arrays) are arranged parallel to each other in the Y-axis direction. The treatment liquid inkjet head 34 ejects treatment liquid from the nozzles N, while the four inkjet heads 35 eject inks of different colors from the nozzles N.

[0228] In this embodiment, the first ink composition is ejected from the inkjet head 35 located adjacent to the treatment liquid inkjet head 34 , and the second ink composition is ejected from the inkjet head 35 located farthest from the treatment liquid inkjet head 34 .

[0229] The Y-axis length of the nozzle arrays in the treatment liquid inkjet head 34 and the ink inkjet head 35 is preferably greater than the Y-axis length of the sheet S (recording medium). Inkjet heads with such lengths can record with a single stroke, resulting in excellent recording speeds. However, this increases the amount of ink deposited, making it more likely to cause uneven bleeding. In contrast, the recording device of this embodiment, using the aforementioned recording method, tends to achieve excellent image quality (with regard to uneven bleeding) even when recording with a single stroke.

[0230] exist Figure 2 In the figure, the nozzle array for ejecting the processing liquid of the inkjet head 34 for processing liquid is arranged to have a portion overlapping with the nozzle array for ejecting ink of the inkjet head 35 for ink in the nozzle array direction (Y-axis direction) when projected along the head movement direction (X-axis direction).

[0231] If this arrangement is adopted, the treatment liquid attachment process and each ink attachment process in the above-mentioned recording method can be performed by scanning while moving the treatment liquid inkjet head and the ink inkjet head relative to the recording medium, and can be performed by attaching the treatment liquid and the ink composition to the same scanning area (simultaneous spraying) in the same said scanning.

[0232] exist Figure 2 In the example, the number of inkjet heads is five, but the number of inkjet heads can be at least one; for example, it can be 7 to 20 or less. The number of inkjet heads is also the number of nozzle arrays. An inkjet head is a unit that ejects a single type of ink or process liquid, and is also a nozzle array. Alternatively, the number of inkjet heads can be used as the number of inks.

[0233] Return to Figure 1 Continuing with the description, the carriage 32 of the recording unit 31 configured as described above is capable of moving integrally with the support plate 33, the inkjet head 34 for the processing liquid, and the inkjet head 35 for the ink. Specifically, an X-axis guide rail 37 extending parallel to the X-axis direction is provided within the printing chamber 3. The carriage 32 moves in the X-axis direction along the X-axis guide rail 37 when driven by the X-axis motor.

[0234] The recording unit 31 then moves (scans) the carriage 32 in the X-axis direction (main scanning direction, scanning direction) above the platen 30. Simultaneously, the process liquid is ejected from the process liquid inkjet head 34 and the ink is ejected from the inkjet head 35. During the same scan, the process liquid and ink composition adhere to the same scanning area, thereby printing an image on the surface of the sheet S, which is resting on the upper surface of the platen 30. This prints a two-dimensional image corresponding to the scan distance in the X-axis direction for one frame, along the length of the nozzle array in the Y direction. Furthermore, the ink pigments that constitute the two-dimensional image are aggregated by the process liquid and fixed to the surface of the sheet S.

[0235] The above-described single-frame printing is repeated while the sheet S is intermittently moved in the X-axis direction. Specifically, a predetermined area covering substantially the entire upper surface of the platen 30 serves as the printing area. The printing area is the area of ​​the recording medium supported by the platen to which ink can adhere during recording. Specifically, if an image to be recorded exists within this area, ink is applied.

[0236] The printing area is also called the attachment area A. The printing area is Figure 1 The area of ​​the recording medium supported by the platen in the X-axis range indicated by A in the figure. The length of the printing area in the X-axis direction is referred to as length A. Length A is the length of the attachment area A in the recording medium conveyance direction, and in the figure, it is the length in the X-axis direction.

[0237] Printing area in Figure 1 The Y-direction range of the printing area is the Y-direction range of the recording medium supported by the platen during recording to which ink can adhere, for example, the Y-direction length range of the nozzle array of the inkjet head.

[0238] The sheet S is intermittently conveyed in the X-axis direction with a distance (intermittent conveyance distance) corresponding to the length of the printing area in the X-axis direction as a unit, and one frame of printing is performed on the sheet S stopped on the upper surface of the platen 30 during the intermittent conveyance.

[0239] In other words, when printing of one frame is completed on the sheet S stopped at the platen 30, the sheet S is conveyed only by the intermittent conveyance distance in the X-axis direction, and the unprinted side of the sheet S stops at the platen 30. Next, printing of one frame is performed again on this unprinted side, and when this printing is completed, the sheet S is again conveyed only by the intermittent conveyance distance in the X-axis direction. This series of operations is then repeated.

[0240] Recording one frame onto a stopped recording medium can be performed with one stroke as described above, or with two or more strokes. When recording with two or more strokes, the inkjet head can be moved in the Y direction between strokes. In this case, the recording resolution in the Y direction can be improved, which is preferred. Preferably, the recording resolution is 10 or less, and more preferably, 6 or less. Fewer strokes result in a faster recording speed, which is also preferred.

[0241] When recording is performed in one pass or two or more passes, the distance of one transport may be shorter than the length A. For example, the distance of one transport may be set to length A / number of passes, and scanning and transport may be performed alternately.

[0242] Furthermore, to maintain the sheet S flat when stopped on the upper surface of the platen 30 during intermittent conveyance, the platen 30 may also include a mechanism for sucking the sheet S stopped on its upper surface. Specifically, a plurality of suction holes (not shown) are provided on the upper surface of the platen 30, and a suction unit 38 is mounted on the lower surface of the platen 30. The suction unit 38 generates negative pressure in the suction holes on the upper surface of the platen 30, thereby sucking the sheet S onto the upper surface of the platen 30. The suction unit 38 may include, for example, a fan (not shown) to generate the negative pressure in the suction holes.

[0243] While the sheet S is resting on the platen 30 for printing, the suction unit 38 sucks the sheet S to keep it flat. When printing is finished, the suction unit 38 stops sucking the sheet S, allowing the sheet S to be conveyed smoothly.

[0244] In this embodiment, the platen 30 is not connected to a heat source such as a heater. In other words, the platen 30 does not include a device for conductively heating the recording medium supported by the platen 30. This simplifies the recording device and saves space. Furthermore, it is easy to install other mechanisms such as the suction unit 38 below the platen 30.

[0245] Furthermore, in the recording device according to this embodiment, a blower fan can be installed on the platen 30, a location where the ink composition adheres, to blow air from above toward the recording medium. This can accelerate image drying and achieve even better image quality. Examples of blower fans include carriage fans installed near the head and ceiling fans that blow air from above. However, even with these configurations, the surface temperature of the recording medium during ink adhesion must be between 27°C and 38°C.

[0246] In this manner, the sheet S having been printed on for one frame is moved from the platen 30 to the drying section 4 as the sheet S is intermittently conveyed. The drying section 4 can perform a post-heating process to completely dry the processing liquid or ink composition that has landed on the sheet S using heated air for drying. The drying section 4 can also be configured using a conduction type, a convection type (air supply), or a radiation type (IR heater, etc.).

[0247] In the drying section 4 , the sheet S is preferably heated so that the surface temperature thereof reaches 30.0° C. to 120.0° C., preferably 40.0° C. to 100.0° C., more preferably 50.0° C. to 95° C., and even more preferably 70° C. to 90° C.

[0248] Then, the sheet S that has been dried reaches the winding unit 5 while being intermittently conveyed, and is wound into a roll R2 .

[0249] Here, the drying section 4 corresponds to the heating mechanism, and the platen 30 corresponds to the recording medium support. Furthermore, the rollers are responsible for the conveying process. Furthermore, the recording unit 31 includes an inkjet head. The platen 30 (recording medium support) does not include a device for conductively heating the recording medium (sheet S) supported by it.

[0250] Furthermore, the drying section 4 (heating mechanism) is located within a space extending from the ink composition-adhering area A (printing area) of the recording medium (sheet S) supported by the platen 30 (recording medium support) toward the side opposite the inkjet head (recording unit 31). In other words, the drying section 4 includes a portion located within the space extending from the ink composition-adhering area A of the recording medium supported by the platen 30 toward the side opposite the inkjet head. In other words, at least a portion of the drying section 4 is located within this space. This allows the residual heat generated by the drying section 4 to heat the recording medium in the adhering area A.

[0251] From the perspective of achieving more sufficient heating, it is preferred that the drying section 4 be located at least half of the range (length A) of the space extending vertically from the attachment area A in the recording medium conveyance direction, and more preferably, the drying section 4 be located at least 70% of the range.

[0252] The length of the drying section 4 in the recording medium conveying direction ( Figure 1 The length of the drying section 4 (in the X direction) is preferably greater than the length of the recording medium conveyed during recording. Furthermore, the length is preferably greater than half the length A of the attachment area A in the recording medium conveyance direction, and more preferably greater than the length A of the attachment area A in the recording medium conveyance direction. The length of the drying section 4 is the length of the portion of the drying section 4 where the recording medium is heated.

[0253] Furthermore, it is understood that even when the heating section 4 is offset relative to the adhesion area A in the Y direction of the figure, it can be arranged to have a portion located in the space extending from the adhesion area A in the extension direction opposite to the inkjet head (recording unit 31).

[0254] The waste heat generated by the drying unit 4 can be transferred to the recording medium support unit via the air between the drying unit 4 and the recording medium support unit. Alternatively, a member fixing the drying unit and the recording medium support unit may be provided between them so that the waste heat is transferred to the recording medium support unit via the member.

[0255] In addition, in the present embodiment, the recording medium supporting portion does not include a device for conductively heating the recording medium supported by the recording medium supporting portion, except for the drying portion 4 .

[0256] The drying section 4 is a device that conveys and heats the recording medium after the attachment step, and is not a device that is originally used to heat the recording medium supported by the recording medium support section.

[0257] By utilizing the residual heat of the drying section 4 to heat the recording medium supported by the recording medium supporting section, the residual heat of the drying section 4 can be effectively utilized, resulting in excellent energy saving and image quality.

[0258] In the drying section, the recording medium is preferably heated for at least 5 seconds, more preferably at least 8 seconds, and even more preferably at least 10 seconds. While this time is not limited, it is preferably 20 seconds or less, more preferably 15 seconds or less, and even more preferably 13 seconds or less. This is preferred in terms of achieving superior abrasion resistance and reducing thermal damage to the recording medium.

[0259] Figure 3 FIG. 1 is a front view schematically showing another example of a serial recording device. Figure 3 In the Figure 1 Components of the recording device 100 having the same functions as those described in the preceding are denoted by the same reference numerals, and detailed descriptions thereof are omitted. Figure 3 , only the configuration for explaining the arrangement of components and the like is shown.

[0260] like Figure 3 As shown, in the recording apparatus 101, the platen 30 (recording medium support portion) also does not include a device for conductively heating the recording medium (sheet S) supported by the platen 30. Furthermore, the drying section 4 (heating mechanism) includes a portion outside the space extending in a direction opposite to the inkjet head (recording unit 31) from the adhesion region A of the recording medium (sheet S) supported by the platen 30 (recording medium support portion), to which the ink composition can adhere, and a portion within the space, but also includes a portion located within the space.

[0261] Figure 4 FIG. 1 is a front view schematically showing another example of a serial recording device. Figure 4 In the Figure 1 Components of the recording device 100 having the same functions as those described in the preceding are denoted by the same reference numerals, and detailed descriptions thereof are omitted. Figure 4 , only the configuration for explaining the arrangement of components is shown.

[0262] like Figure 4As shown, in the recording apparatus 102, a sheet S is conveyed to the drying section 4 (heating mechanism) and passes through two conveyance paths within the drying section 4. After passing through the drying section 4 twice, the sheet S is conveyed between the platen 30 (recording medium support) and the drying section 4 (heating mechanism), passes through a conveyance path SB, and is wound into a roll R2. While the conveyance path SB is not the conveyance path used in the conveying process, where the recording medium, after undergoing the treatment liquid and ink adhesion processes, is conveyed to the heating mechanism, a conveyance path in the conveying process may also be provided between the platen 30 (recording medium support) and the drying section 4 (heating mechanism) (not shown).

[0263] like Figure 4 In the case where a transport path for transporting the recording medium is provided between the recording medium support portion and the heating mechanism as in the recording device 102, the heat generated by the heating mechanism can be more effectively utilized, and the space within the device can be more effectively and flexibly utilized. Figure 4 If the heating mechanism is provided in two stages, as in the recording device 102, secondary heating can be more effectively performed and the recording device can be made more compact in the horizontal direction (X direction). Alternatively, the heating mechanism may be provided in two or more stages within the space opposite the inkjet head relative to the recording medium support, starting from the area of ​​the recording medium supported by the recording medium support and undergoing the ink deposition process.

[0264] exist Figure 4 In the recording device 102, the platen 30 (recording medium support portion) also does not include a device for conductively heating the recording medium (sheet S) supported by the platen 30. Furthermore, the drying section 4 (heating mechanism) includes a portion within a space extending from the ink composition-adhering region A of the recording medium (sheet S) supported by the platen 30 (recording medium support portion) in a direction opposite to the inkjet head (recording unit 31).

[0265] This arrangement places a heating mechanism beneath the platen, omitting the need for conductive heating of the platen. Instead, the platen is heated using the residual heat of the heating mechanism, resulting in superior image quality. While the temperature of the recording medium within the platen remains relatively low, the combined use of the processing fluid and the resulting excellent image quality is achieved. The lack of a heat source within the platen also contributes to lower costs. Furthermore, this approach is effective in terms of space and energy savings, and the relatively low temperature of the recording medium within the platen reduces head clogging and condensation.

[0266] On the other hand, Figure 1 、 Figure 3 as well as Figure 4The figure shows the shortest distance D between the recording medium on the recording medium support where ink is deposited and the recording medium being heated by the heating mechanism. Distance D represents the shortest distance in the vertical direction (Z direction) between the recording medium in the depositing area A and the recording medium in the heating mechanism. In other words, it is the shortest distance in the vertical direction relative to the plane of the depositing area A. Figure 4 When there are a plurality of drying sections, the distance is closer to the recording medium supporting section.

[0267] The shortest distance D between the recording medium on the recording medium support where ink is deposited and the recording medium undergoing the heating process by the heating mechanism is preferably 100 mm to 1000 mm, more preferably 150 mm to 800 mm, and even more preferably 200 mm to 700 mm. Furthermore, it is preferably 250 mm to 600 mm, more preferably 300 mm to 500 mm, even more preferably 350 mm to 480 mm, and particularly preferably 400 mm to 470 mm.

[0268] This arrangement makes the spatial distance between the recording medium support and the heating mechanism more appropriate, making it easier to reduce clogging of the head nozzles. In addition, it is easier to keep the recording medium surface temperature in the attachment area A within a predetermined range, which is preferable.

[0269] As described above, recording devices 100, 101, and 102 perform the ink adhesion process on a recording medium that is supported and stopped by a recording medium support. In a serial system, the head deposits ink by scanning the recording medium while it is stopped on the platen. This makes it easier for the recording medium to heat up on the platen even at low temperatures, making this a preferred method. Furthermore, in this case, the number of strokes in the ink adhesion process on the stopped recording medium is preferably 6 or less, more preferably 2 or less, and even more preferably 1.

[0270] The recording device used in the recording method of this embodiment may also be a line-type recording device. In the examples of the recording devices 100, 101, and 102 described above, the recording unit 31 scans the stopped recording medium to perform the ink adhesion process. In contrast, in the case of a line-type recording device, the recording medium is continuously conveyed on the platen 30, and the recording unit 31, which is fixed therebetween, ejects a treatment liquid, ink composition, etc., to perform the ink adhesion process.

[0271] Even in such a line recording device, the drying section 4 (heating mechanism) can be located in a space extending from the adhesion area A to which the ink composition can adhere of the recording medium (sheet S) supported by the platen 30 (recording medium support section) toward the opposite side of the inkjet head (recording unit 31). In addition, in the case of a line recording device, the adhesion area A is defined by the positions of the nozzles located upstream and downstream in the direction of conveyance of the recording medium. For example, Figure 1 In the embodiment, the recording unit 31 is fixed at the position shown in the figure, and the ink is deposited while the recording medium is transported in the X direction relative to the fixed recording unit. In this case, the depositing area A is the range from the nozzle of the inkjet head at one end in the X direction to the nozzle of the inkjet head at the other end.

[0272] Even in the line type, the recording medium can be heated when the recording medium passes over the platen.

[0273] Figure 5 1 is a perspective view schematically showing the periphery of an inkjet head and a recording medium support portion of another example of a serial recording device. Figure 5 There are also Figure 1 The components having the same functions as those of the recording device 100 described in the previous section are omitted. Figure 5 In the figure, parts of the drying section, recording medium conveying mechanism, etc. are also omitted.

[0274] The recording apparatus 1 includes an inkjet head 2, a carriage housing 9, a carriage main body 12, a platen 11, a carriage moving mechanism 13, a transport unit 14, and a control unit CONT. The control unit CONT controls the overall operation of the recording apparatus 1.

[0275] The inkjet head 2 moves in the Y direction while performing scanning by ejecting ink from its nozzles. Furthermore, the recording medium M is transported in the X direction by a transport unit 14. The inkjet head 2 is mounted on the bottom surface of the carriage. This is a recording device in which the scanning direction intersects the transport direction.

[0276] exist Figure 5 In the example of a recording device, recording is performed by alternately scanning and conveying. The adhesion area A is an area where ink can adhere to the recording medium M supported by the platen 11 during recording, and is an area facing the inkjet head 2 when the inkjet head 2 is scanning. The inkjet head 2 can be Figure 2 Same, will Figure 2 The X-direction arrangement is Figure 5 Y direction.

[0277] Opposing the inkjet head 2 strictly means opposing the nozzle array included in the inkjet head 2 .

[0278] The drying section (not shown) is located in a space extending downward in the Z direction from the plane of the attachment area A. After the recording medium M is conveyed from the platen to the downstream side in the X direction, the conveying direction is changed to the downward direction in the Y direction by rollers (not shown). Further below the platen in the Y direction, the conveying direction is further changed to the upper right direction in the X direction in the figure, and reaches the drying section. This is similar to Figure 1 same.

[0279] exist Figure 5 In the example of the recording device, the length of the attachment area A in the X direction is Figure 1 Although it is shorter than the example of , this example also has excellent image quality, clogging resistance, etc.

[0280] According to the recording device of this embodiment, the recording medium support portion does not include a device for conductively heating the recording medium supported by the recording medium support portion. Therefore, the inkjet head is less likely to be heated, which reduces nozzle clogging and facilitates the aforementioned recording method. Furthermore, the use of a treatment liquid in this recording device allows for early fixing of the ink, resulting in the formation of high-quality images with well-filled ink and minimal unevenness in shading.

[0281] 1.8. Effects, etc.

[0282] According to the recording method of this embodiment, the recording medium support does not include a device for conductively heating the recording medium supported by the recording medium support. Therefore, the inkjet head is less likely to be heated, reducing nozzle clogging. Furthermore, the use of a treatment liquid allows for early fixing of the ink, resulting in the formation of high-quality images with well-filled ink and minimal unevenness in shading.

[0283] The recording method of this embodiment utilizes a processing liquid, achieving high image quality without relying too heavily on a primary drying process. High primary drying temperatures can lead to clogging of the head nozzles and condensation on the nozzle surface. However, the recording method of this embodiment avoids excessively high primary drying temperatures. Specifically, the recording method of this embodiment utilizes not only a processing liquid but also a primary drying process at a moderate temperature to achieve excellent image quality.

[0284] 2. Examples and Comparative Examples

[0285] The present invention is described in detail below using examples, but the present invention is not limited to these examples. "Parts" and "%" are by mass unless otherwise specified. Unless otherwise specified, evaluations were performed at a temperature of 25.0°C and a relative humidity of 40.0%.

[0286] 2.1. Preparation of treatment liquid and ink composition

[0287] The components were placed in a container to form the composition shown in Table 1, 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 liquids, non-white inks, and white inks according to the Examples and Comparative Examples. The following pigment dispersion was prepared and used.

[0288] The substances other than those described by compound name in Table 1 are as follows.

[0289] Cationic polymers: "CatioMaster PD-7, polyamine resin (epichlorohydrin-amine derivative resin)" manufactured by Yokkaichi Gosei Co., Ltd.

[0290] Carbon black: No. 33 (manufactured by Mitsubishi Chemical Corporation)

[0291] Dispersant resin, Resin C (anionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 90)

[0292] Dispersant resin, Resin A (anionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 40)

[0293] Dispersant resin, Resin B (nonionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 0)

[0294] Resin particles, styrene acrylic A: refer to the following (high cohesion)

[0295] Resin particles, styrene acrylic B: refer to the following (low cohesion)

[0296] Wax, polyethylene: "Nopcote PEM-17" (trade name, manufactured by San Nopco Co., Ltd.)

[0297] Surfactant: Silicone surfactant "BYK348" manufactured by BYK

[0298] 1,2-HD: 1,2-hexanediol

[0299] (Preparation of Resin Particles: Styrene Acrylic B)

[0300] Resin Emulsion B (acid value 7 mgKOH / g) was obtained by emulsion copolymerization of 75 parts by mass of styrene, 0.8 parts by mass of acrylic acid, 14.2 parts by mass of methyl methacrylate, and 10 parts by mass of cyclohexyl methacrylate. Newcol NT-30 (manufactured by Nippon Emulsifier Co., Ltd.) was used as an emulsion polymerization surfactant in an amount of 2 parts by mass based on 100 parts by mass of the total monomer amount.

[0301] (Preparation of Resin Particles: Styrene Acrylic A)

[0302] Resin emulsion A (acid value: 30 mgKOH / g) was obtained in the same manner as above except that the monomer composition was changed. The amount of the surfactant for emulsion polymerization was 1 part by mass based on 100 parts by mass of the total monomer amount.

[0303] (Preparation of Pigment Dispersion)

[0304] <White Pigment Dispersion Using Resin A>

[0305] First, 12 parts by mass of Resin A, a resin dispersant, was added and dissolved in 155 parts by mass of ion-exchanged water containing 0.1 parts by mass of a 30% aqueous ammonia solution (neutralizer). 40 parts by mass of titanium dioxide (CI Pigment White 6), a white pigment, was added and dispersed in a bead mill using zirconia beads for 10 hours. Subsequently, the mixture was centrifugally filtered to remove coarse particles, dust, and other impurities, and the concentration of the white pigment was adjusted to 20% by mass to obtain a white colorant dispersion. The average particle size of the white pigment was 350 nm.

[0306] <White Pigment Dispersion Using Resin B>

[0307] A white colorant dispersion was obtained in the same manner except that Resin B was used as the resin dispersant. The average particle size of the white pigment was 350 nm.

[0308] <Non-white Pigment Dispersion Using Resin C>

[0309] A non-white colorant dispersion (black) was obtained in the same manner except that Resin C was used as the resin dispersant, carbon black was used as the colorant, and the amount of the resin dispersant added was such that the mass ratio of the resin dispersant to the pigment was the mass ratio shown in Table 1. The average particle size of the pigment was 60 nm.

[0310] Evaluation methods

[0311] 2.2.1. Viscosity increase rate

[0312] The viscosity increase (times) when mixing at a mass ratio of 10:1 (ink: 7% by mass calcium formate aqueous solution) in Table 1 is obtained by mixing each ink and a 7% by mass calcium formate aqueous solution at a mass ratio of 10:1 and stirring for 1 minute, and then measuring the viscosity using a rheometer (MCR302 / manufactured by Anton Paar) at 25°C and a shear rate of 200 s. -1 When measuring the viscosity of a mixed liquid under the conditions of , the ratio of the viscosity of the mixed liquid after mixing to the viscosity of the ink before mixing. When measuring the viscosity of a mixed liquid, collect the mixed liquid after it has been thoroughly stirred.

[0313] 2.2.2. Recording test

[0314] Filling ink and processing fluid into the modified SurePress L-4733A digital label printing machine, such as Figure 1 The configuration shown is as a serial recording device.

[0315] The surface temperature of the recording medium in the drying section 4 (heating mechanism) was set to 75° C. PET50A (manufactured by Lintec Corporation) was used as the recording medium.

[0316] The nozzle density of the recording head was 1200 dpi, and based on a recording resolution of 1200×1200 dpi, the number of droplets per pixel was adjusted so that the deposition amount would be the value in each test described below. The mass of the treatment liquid droplets was 3 ng, and the mass of the ink droplets was 7 ng.

[0317] The air supply mechanism blows air from above the platen toward the recording medium. The air is supplied at a temperature of 25°C and at the speeds listed in the table.

[0318] The table shows the time (residence time) that a certain portion of the recording medium is heated in the drying section.

[0319] In the table, examples where the drying section is located within the space extending vertically downward from the attachment area A are assumed to have the heater located below the platen. Examples where the drying section is not located are assumed to have the drying section located completely to the right in the X direction relative to the space extending vertically downward from the attachment area A.

[0320] The table shows the distance in the Y direction between the recording medium in the adhesion area A and the recording medium in the drying area. This distance was changed in some examples.

[0321] The example in which the platen does not have a heater is an example in which no device for conductively heating the recording medium supported by the platen is provided, and is described as "none" in the table.

[0322] The table also lists the printing strokes. In all cases, the conveyance distance is the length A in the X direction. In the two-stroke example, the recording medium is not conveyed during the two strokes, but is conveyed after the two strokes. The amount of ink, etc. deposited is the same as in the one-stroke example, with half of the amount deposited being applied over the two strokes. The same applies to cases with two or more strokes.

[0323] The number of strokes refers to the number of strokes per ink. During each stroke of an ink, the treatment liquid is applied in an overlapping manner. For the example using white ink, first apply the white ink in the number of strokes listed in the table, then apply the white ink in an overlapping manner for the same number of strokes. The treatment liquid is applied in an overlapping manner for half the amount applied during the same stroke as the white ink, and the remaining amount applied during the same stroke as the non-white ink. The recording medium is not transported during this period.

[0324] 2.2.3. Image Filling and Pinhole Evaluation

[0325] In the example of the treatment liquid + non-white ink, the injection amounts are as follows.

[0326] Treatment fluid 1.5mg / inch 2

[0327] Non-white ink 7.0mg / inch 2

[0328] In the example of processing liquid+white ink+non-white ink, the injection amounts are as follows.

[0329] Treatment fluid 1.5mg / inch 2

[0330] White ink 7.0mg / inch 2

[0331] Non-white ink 3.0mg / inch 2

[0332] The solid image area of ​​the obtained recorded object was visually observed under a fluorescent lamp and evaluated according to the following criteria. The results are shown in Tables 2 to 4.

[0333] A: There are no unfilled areas or pinholes.

[0334] B: Several unfilled areas and pinholes are visible.

[0335] C: Unfilled areas and pinholes are clearly seen.

[0336] 2.2.4. Evaluation of Image Unevenness

[0337] In the example of the treatment liquid + non-white ink, the injection amounts are as follows.

[0338] Treatment fluid 1.5mg / inch 2

[0339] Non-white ink 9.0mg / inch 2

[0340] In the example of processing liquid+white ink+non-white ink, the injection amounts are as follows.

[0341] Treatment fluid 1.5mg / inch 2

[0342] White ink 9.0mg / inch 2

[0343] Non-white ink 5.0mg / inch 2

[0344] The solid image area of ​​the obtained recorded object was visually observed under a fluorescent lamp and evaluated according to the following criteria. The results are shown in Tables 2 to 4.

[0345] A: There is no unevenness in light and dark.

[0346] B: Some unevenness is visible.

[0347] C: Uneven shading is clearly seen.

[0348] D: Uneven density is clearly observed, and the ink seeps into the outline of the pattern and does not form a straight line.

[0349] 2.2.5. Evaluation of blockage

[0350] After one hour of continuous printing under the recording test conditions, suction cleaning was performed to restore the nozzles that were not ejecting ink, and a nozzle check was performed. Each cleaning cycle discharged 1cc of ink from the nozzle array. Evaluation was performed according to the following criteria, and the results are reported in Tables 2 to 4.

[0351] A: All nozzles are restored within one cleaning.

[0352] B: All nozzles are restored within three cleanings

[0353] C: Cleaned four times with unrestored nozzles

[0354] 2.2.6. Evaluation of condensation on the nozzle surface

[0355] Image recording was performed three times for one hour continuously for each nozzle row of ink under the conditions shown in the table (a total of 3 hours). After recording, the nozzles of the nozzle group were inspected and the nozzle surface observed. Failure to discharge or deviation of the nozzles by more than half the distance between adjacent nozzles was considered a discharge failure. The presence of deflection caused by contact with condensation was evaluated. Evaluation was performed according to the following criteria, and the results are reported in Tables 2 to 4.

[0356] A: There is no condensation on the nozzle surface. There are no defective nozzles.

[0357] B: Some condensation occurred on the nozzle surface. 3% or less of the nozzles had defective discharge.

[0358] C: Considerable condensation has occurred on the nozzle surface. More than 3% of nozzles are defective.

[0359] 2.2.7. Evaluation of abrasion resistance

[0360] The recorded material was evaluated under the same conditions as for the unevenness of shading. The recorded area was moistened with water using plain cloth and the degree of ink peeling was visually observed after 50 rubs using a Gakushin abrasion tester (load 500g). Evaluation was performed according to the following criteria, and the results are reported in Tables 2 to 4.

[0361] A: Peeling is within 10% of the evaluation area

[0362] B: Peeling exceeds 10% of the evaluation area

[0363] Evaluation results

[0364] As shown in Tables 2 to 4, the ink composition is an aqueous ink composition containing a colorant, the ink adhesion process is performed on a recording medium supported by a recording medium support, the recording medium support does not include a device for conductively heating the recording medium, and the heating mechanism includes a portion located in a space extending from the ink composition adhesion region of the recording medium supported by the recording medium support in a direction opposite to the inkjet head. The surface temperature of the recording medium supported by the recording medium support during the ink adhesion process is between 27°C and 38°C. The results of each example show improved image quality (filling, pinholes, and unevenness in shading). It was found that clogging is less likely to occur.

[0365] In addition, although not listed in the table, Figure 1 The recording device was transformed into a line recording device as described above, and then recording was performed in the same manner as in the embodiment, and excellent evaluation results were obtained. Figure 1 The recording device is used as Figure 4 In a recording device in which the drying section is heated twice, the abrasion resistance tends to be more excellent.

[0366] The present invention includes structures that are substantially the same as the structures described in the embodiments, such as structures having the same functions, methods, and results, or structures having the same purposes and effects. In addition, the present invention includes structures that replace non-essential parts of the structures described in the embodiments. In addition, the present invention includes structures that can have the same effects as the structures described in the embodiments or structures that achieve the same purposes. In addition, the present invention includes structures that add known technologies to the structures described in the embodiments.

[0367] The following contents are derived from the above-mentioned embodiment and modification examples.

[0368] The record method has:

[0369] a treatment liquid attachment step of attaching the treatment liquid containing the coagulant to the recording medium;

[0370] an ink adhesion step of causing the ink composition to be ejected from the inkjet head and adhere to the recording medium;

[0371] a conveying step of conveying the recording medium having undergone the treatment liquid adhering step and the ink adhering step to a heating mechanism; and

[0372] a heating step of heating the recording medium conveyed by the conveying step by using the heating mechanism;

[0373] The ink composition is a water-based ink composition containing a colorant,

[0374] The ink adhesion step is performed on the recording medium supported by the recording medium support portion.

[0375] The recording medium support portion does not have a device for conductively heating the recording medium supported by the recording medium support portion.

[0376] The heating mechanism includes a portion located in a space extending from a region of the recording medium supported by the recording medium support portion to which the ink composition can adhere in an extending direction opposite to the inkjet head.

[0377] The surface temperature of the recording medium supported by the recording medium supporting portion and subjected to the ink adhering step is 27° C. or higher and 38° C. or lower.

[0378] According to this recording method, the recording medium support does not include a device for conductively heating the recording medium supported by the recording medium support. Therefore, the inkjet head is less likely to be heated, which can reduce nozzle clogging. Furthermore, according to this recording method, the use of a treatment liquid allows for early fixing of the ink, resulting in the formation of high-quality images with well-filled ink and minimal unevenness in shading.

[0379] In the above recording method,

[0380] The shortest distance between the recording medium positioned on the recording medium supporting portion and to which ink is deposited and the recording medium being heated by the heating mechanism may be 200 mm to 700 mm.

[0381] According to this recording method, the spatial distance between the recording medium support portion and the heating mechanism is more appropriate, and thus nozzle clogging is more easily reduced.

[0382] In the above recording method,

[0383] An air blowing step may be performed during the ink adhering step.

[0384] According to this recording method, the ink can be fixed earlier, and an image with better quality can be formed.

[0385] In the above recording method,

[0386] The wind speed in the air supply step may be greater than or equal to 2 m / s and less than or equal to 15 m / s.

[0387] According to this recording method, the ink can be fixed earlier, and an image with better quality can be formed.

[0388] In the above recording method,

[0389] The ink attaching step may be performed on the recording medium that is supported by the recording medium supporting portion and is in a stopped state.

[0390] In the above recording method,

[0391] The number of passes in the ink adhesion step may be 6 or less.

[0392] In the above recording method,

[0393] The coagulant may also be selected from multivalent metal salts.

[0394] According to this recording method, an image with better quality can be formed.

[0395] In the above recording method,

[0396] When the ink composition and the calcium formate aqueous solution are mixed at a mass ratio (ink composition:aqueous solution) of 10:1, the viscosity increase ratio may be 5 times or more.

[0397] According to this recording method, an image with better quality can be formed.

[0398] In the above recording method,

[0399] The ink composition may also include a non-white ink containing a non-white colorant and a white ink containing a white colorant.

[0400] In the above recording method,

[0401] The time during which the recording medium is heated by the heating mechanism may be 3 seconds or longer and 25 seconds or shorter.

[0402] According to this recording method, a sufficiently dry image can be formed at high speed.

[0403] In the above recording method,

[0404] A conveyance path for conveying the recording medium may be provided between the recording medium supporting portion and the heating mechanism.

[0405] According to this recording method, the heat generated by the heating mechanism can be used more effectively.

[0406] In the above recording method,

[0407] The ink composition may contain 10% by mass or more and 35% by mass or less of an organic solvent.

[0408] The recording device performs any of the above recording methods, and the recording device has:

[0409] the treatment fluid;

[0410] the ink composition;

[0411] a treatment liquid attachment mechanism for performing the treatment liquid attachment process;

[0412] the inkjet head;

[0413] A conveying mechanism for carrying out the conveying process;

[0414] the heating mechanism; and

[0415] The recording medium supporting portion.

[0416] According to this recording device, the recording medium support portion does not include a device for conductively heating the recording medium supported by the recording medium support portion. Therefore, the inkjet head is less likely to be heated, which can reduce nozzle clogging. In addition, according to this recording device, the use of a treatment liquid allows for early fixing of the ink, resulting in the formation of high-quality images with good filling and minimal unevenness in light and dark areas.

Claims

1. A recording method, characterized in that: have: a treatment liquid attachment step of attaching the treatment liquid containing the coagulant to the recording medium; an ink adhesion step of causing the ink composition to be ejected from the inkjet head and adhere to the recording medium; a conveying step of conveying the recording medium having undergone the treatment liquid adhesion step and the ink adhesion step to a heating mechanism; as well as a heating step of heating the recording medium conveyed by the conveying step by using the heating mechanism; The ink composition is a water-based ink composition containing a colorant, The ink adhesion step is performed on the recording medium supported by the recording medium support portion. The recording medium support portion does not include a device for conductively heating the recording medium supported by the recording medium support portion. The heating mechanism includes a portion located in a space extending from a region of the recording medium supported by the recording medium support portion to which the ink composition can adhere in an extending direction opposite to the inkjet head. The surface temperature of the recording medium supported by the recording medium supporting portion and subjected to the ink adhering step is 27° C. or higher and 38° C. or lower.

2. The recording method according to claim 1, wherein The shortest distance between the recording medium positioned on the recording medium supporting portion and to which ink is deposited and the recording medium being heated by the heating mechanism is 200 mm to 700 mm.

3. The recording method according to claim 1, wherein In the ink adhesion step, an air blowing step is performed.

4. The recording method according to claim 2, wherein: The wind speed in the air supply step is greater than or equal to 2 m / s and less than or equal to 15 m / s.

5. The recording method according to claim 1, wherein The ink adhesion step is performed on the recording medium that is supported and stopped by the recording medium support portion.

6. The recording method according to claim 1, wherein The number of passes in the ink adhesion step is 6 or less.

7. The recording method according to claim 1, wherein The coagulant is selected from multivalent metal salts.

8. The recording method according to claim 1, wherein When the ink composition and the calcium formate aqueous solution are mixed at a mass ratio of 10:1, the viscosity increasing ratio is 5 times or more.

9. The recording method according to claim 1, wherein The ink composition includes a non-white ink containing a non-white colorant and a white ink containing a white colorant.

10. The recording method according to claim 1, wherein The time for which the recording medium is heated by the heating mechanism is 3 seconds or longer and 25 seconds or shorter.

11. The recording method according to claim 1, wherein A conveyance path for conveying the recording medium is provided between the recording medium supporting portion and the heating mechanism.

12. The recording method according to claim 1, wherein The ink composition contains 10% by mass or more and 35% by mass or less of an organic solvent.

13. A recording device, characterized in that: A recording device for performing the recording method according to any one of claims 1 to 12, the recording device comprising: the treatment fluid; the ink composition; a treatment liquid attachment mechanism for performing the treatment liquid attachment process; the inkjet head; A conveying mechanism for carrying out the conveying process; the heating mechanism; and The recording medium supporting portion.

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