Recording method and recording device

Abstract

To provide a recording method excellent in image quality (burying, pin hole, shade irregularities), and hardly causing clogs.SOLUTION: A recording method includes the steps of: a process liquid attaching step of attaching a coagulant-containing process liquid to a recording medium; an ink attaching step of discharging an ink composition from an ink jet head and attaching it to the recording medium; a conveyance step of conveying the recording medium subjected to the process liquid attaching step and the ink attaching step to a heating mechanism; and a heating step of heating the recording medium conveyed in the conveyance step by the heating mechanism. The ink composition is an aqueous ink composition containing a coloring material. The ink attaching step performs on the recording medium supported on a recording medium support part. The recording medium support part does not have a device for heating in a conduction manner the recording medium supported by the recording medium support part. The heating mechanism has a part positioned in a space extending in a vertical direction at an opposite side to the ink jet head from an area where the ink composition can attach to the recording medium supported by the recording medium support part. A surface temperature of the recording medium supported by the recording medium support part and subjected to the ink attaching step is 27°C or higher and 38°C or lower.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] BACKGROUND ART An inkjet recording method is known in which minute ink droplets are ejected from the nozzles of an inkjet head of an inkjet recording device to record an image on a recording medium, and its use in, for example, sign printing, label printing, packaging printing, and the like is being considered.

[0003] Patent Document 1 discloses a printing machine that uses a drying process. The printing machine described in this document performs primary drying, which dries ink attached to the recording medium, followed by secondary drying. The secondary drying uses a high heating temperature and is carried out downstream in the conveyance direction of the recording medium. On the other hand, the primary drying is carried out near the platen in the printing machine described in this document. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-056832 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the recording medium is heated, clogging of the nozzles of the recording head occurs. On the other hand, when the recording medium is not heated, it is difficult to quickly dry the ink, which can result in insufficient image quality. Furthermore, when the recording medium is heated, it is not possible to simplify the recording device or save space. [Means for solving the problem]

[0006] One aspect of the recording method according to the present invention is to a treatment liquid applying step of applying a treatment liquid containing a flocculant to a recording medium; an ink deposition step of ejecting the ink composition from an inkjet head and depositing it on a recording medium; a conveying step of conveying the recording medium, which has been subjected to the treatment liquid applying step and the ink applying step, to a heating mechanism; a heating step of heating the recording medium conveyed by the conveying step with the heating mechanism; and the ink composition is a water-based ink composition containing a colorant, the ink deposition step is performed on a recording medium supported by a recording medium support unit, the recording medium support does not include a device for conductively heating a recording medium supported by the recording medium support; the heating mechanism has a portion located in a space extending in a direction perpendicular to the ink jet head from a region of the recording medium supported by the recording medium support unit to which the ink composition can be attached, and on a side opposite to the ink jet head; The surface temperature of the recording medium supported by the recording medium support unit and subjected to the ink deposition step is 27°C or higher and 38°C or lower.

[0007] One aspect of the recording device according to the present invention is A recording device that performs the above-mentioned recording method, the treatment liquid; the ink composition; a treatment liquid applying mechanism that performs the treatment liquid applying step; the inkjet head; a conveying mechanism that performs the conveying step; the heating mechanism; The recording medium support portion. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front view schematically illustrating an example of a serial type recording device. [Figure 2] FIG. 2 is a bottom view partially illustrating an example of the configuration of an inkjet head. [Figure 3] FIG. 10 is a front view schematically showing another example of a serial type recording apparatus. [Figure 4] FIG. 10 is a front view schematically showing another example of a serial type recording apparatus. [Figure 5] FIG. 10 is a perspective view schematically illustrating another example of a serial type recording apparatus. [Figure 6] Table 1 shows the formulations of the compositions used in the examples and comparative examples. [Figure 7] Table 2 shows the conditions and evaluation results of the examples. [Figure 8] Table 3 shows the conditions and evaluation results of the examples. [Figure 9] Table 4 shows the conditions and evaluation results of Examples and Comparative Examples. DETAILED DESCRIPTION OF THE INVENTION

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

[0010] 1. Recording method The recording method according to this embodiment includes a treatment liquid application step of applying a treatment liquid containing an aggregating agent to a recording medium, an ink application step of ejecting an ink composition from an inkjet head and applying it to the recording medium, a transport step of transporting the recording medium that has been subjected to the treatment liquid application step and the ink application step to a heating mechanism, and a heating step of heating the recording medium transported by the transport step in the heating mechanism.

[0011] 1.1. Recording medium The recording medium used in the recording method according to the present embodiment is not particularly limited, but examples thereof include absorbent recording media, low-absorbent recording media, and non-absorbent recording media. Among these, low-absorbent recording media and non-absorbent recording media are preferred, and non-absorbent recording media are more preferred. The present invention is useful for non-absorbent recording media, as they are particularly poor at filling.

[0012] Here, a "low-absorbency recording medium" and a "non-absorbency recording medium" are defined as recording media having a water absorption of 10 mL / m2 or less within 30 msec from the start of contact in the Bristow method. 2 This refers to a recording medium that is as follows: The Bristow method is the most widely used method for measuring liquid absorption in a short period of time, and is also adopted by the Japan Pulp and Paper Technical Association (JAPAN TAPPI). Details of the test method are described in Standard No. 51 "Paper and Paperboard - Liquid Absorbency Test Method - Bristow Method" of the "JAPAN TAPPI Paper and Pulp Test Method 2000 Edition."

[0013] Non-absorbent or low-absorbent recording media can also be classified by the wettability of the recording surface with water. For example, a recording medium can be characterized by dropping a 0.5 μL drop of water onto the recording surface of the recording medium and measuring the rate of decrease in contact angle (comparing the contact angle 0.5 milliseconds after impact with the contact angle 5 seconds after impact). More specifically, non-absorbent, as a property of a recording medium, refers to a rate of decrease of less than 1%, low-absorbent refers to a rate of decrease of 1% or more but less than 5%, and absorbent refers to a rate of decrease of 5% or more. The contact angle can be measured using a portable contact angle meter PCA-1 (manufactured by Kyowa Interface Science Co., Ltd.) or the like. This can be done.

[0014] The absorbent recording medium is not particularly limited, but examples thereof include plain paper such as electrophotographic paper, which has high ink composition permeability, inkjet paper (paper specifically for inkjet printing 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 polyvinylpyrrolidone (PVP)), and art paper, coated paper, cast paper, and the like used in general offset printing, which has relatively low ink composition permeability.

[0015] The low-absorbency recording medium is not particularly limited, but examples thereof include coated paper having a coating layer on the surface for receiving oil-based ink, and examples of coated paper include, but are not particularly limited to, printing paper such as art paper, coated paper, and matte paper.

[0016] The non-absorbent recording medium is not particularly limited, but examples thereof include a plastic film having no ink-absorbing layer, a substrate such as paper coated with plastic, or a substrate with a plastic film adhered thereto, etc. Examples of plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc.

[0017] The recording medium may have any shape as long as it can be transported in the transporting step, and may be, for example, a long sheet wound up on a roll or a single sheet of A4 size or the like.

[0018] 1.2. Treatment liquid application process In the treatment liquid application step, a treatment liquid containing a flocculant is applied to the recording medium. The treatment liquid application step can be performed simultaneously with the ink application step, or before or after the ink application step.

[0019] Examples of methods for applying the treatment liquid include dip coating, in which the recording medium is immersed in the treatment liquid, roller coating, in which the treatment liquid is applied using a brush, roller, spatula, roll coater, or the like, spray coating, in which the treatment liquid is sprayed using a spray device, and inkjet coating, in which the treatment liquid is applied by an inkjet method. Of these, the inkjet method is preferred.

[0020] 1.2.1.Processing solution The treatment liquid used in the recording method according to this embodiment is a water-based treatment liquid containing a coagulant.

[0021] 1.2.1.(1) Flocculant The treatment liquid contains an aggregating agent that aggregates the components of the ink composition. The aggregating agent reacts with components such as the colorant contained in the ink and the resin particles that may be contained in the ink, thereby aggregating the colorant and resin particles. However, the degree of aggregation of the colorant and resin particles caused by the aggregating agent varies depending on the type of aggregating agent, colorant, and resin particles, and can be adjusted. Furthermore, the aggregating agent can aggregate the colorant and resin particles by reacting with them. Such aggregation can, for example, enhance the color development of the colorant, improve the fixation of the resin particles, and / or increase the viscosity of the ink.

[0022] The flocculant is not particularly limited, but examples thereof include metal salts, inorganic acids, organic acids, cationic compounds, etc., and examples of the cationic compounds that can be used include cationic resins (cationic polymers), cationic surfactants, etc. Among these, polyvalent metal salts are preferred as metal salts, and cationic resins are preferred as cationic compounds. The flocculant is preferably selected from cationic resins, organic acids, and polyvalent metal salts, as this provides particularly excellent image quality, abrasion resistance, gloss, and the like.

[0023] The metal salt is preferably a polyvalent metal salt, but metal salts other than polyvalent metal salts can also be used. Among these flocculants, it is preferable to use at least one selected from metal salts and organic acids because of their excellent reactivity with the components contained in the ink. Furthermore, among cationic compounds, it is preferable to use cationic resins because they are easily soluble in the treatment liquid. Furthermore, it is also possible to use multiple types of flocculants in combination.

[0024] Polyvalent metal salts are compounds composed of divalent or higher metal ions and anions. Examples of divalent or higher metal ions include calcium, magnesium, copper, nickel, zinc, barium, aluminum, titanium, strontium, chromium, cobalt, and iron ions. Among the metal ions that compose these polyvalent metal salts, at least one of calcium ions and magnesium ions is preferred because they have excellent coagulation properties for ink components.

[0025] The anions constituting the polyvalent metal salt are inorganic or organic ions. That is, the polyvalent metal salt in the present invention is composed of an inorganic or organic ion 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 carboxylate ions.

[0026] The polyvalent metal compound is preferably an ionic polyvalent metal salt, and in particular, when the polyvalent metal salt is a magnesium salt or a calcium salt, the stability of the treatment solution is improved. Calcium salts are particularly preferred. The counter ions of the polyvalent metal may be either inorganic acid ions or organic acid ions.

[0027] Specific examples of the polyvalent metal salt 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, and aluminum acetate. These polyvalent metal salts may be used alone or in combination. Among these, calcium formate, magnesium sulfate, calcium nitrate, and / or calcium chloride are preferred because they can ensure sufficient solubility in water and reduce traces left by the treatment solution (making the traces less noticeable), with calcium formate and calcium nitrate being more preferred. These metal salts may contain water of hydration in their raw material form.

[0028] Examples of metal salts other than polyvalent metal salts include monovalent metal salts such as sodium salts and potassium salts, such as sodium sulfate and potassium sulfate.

[0029] Suitable examples of organic acids include 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, pyronecarboxylic acid, pyrrolecarboxylic acid, furancarboxylic acid, pyridinecarboxylic acid, coumaric acid, thiophenecarboxylic acid, nicotinic acid, or derivatives of these compounds, or salts thereof. One organic acid may be used alone, or two or more organic acids may be used in combination. Metal salts of organic acids are included in the above-mentioned metal salts.

[0030] Examples of inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid, etc. The inorganic acids may be used alone or in combination of two or more.

[0031] Examples of cationic resins (cationic polymers) include cationic urethane resins, cationic olefin resins, cationic amine resins, etc. The cationic polymers are preferably water-soluble.

[0032] As the cationic urethane-based resin, commercially available products can be used, such as Hydran CP-7010, CP-7020, CP-7030, CP-7040, CP-7050, CP-7060, and CP-7610 (trade names, manufactured by Dainippon Ink and Chemicals, Inc.), Superflex 600, 610, 620, 630, 640, and 650 (trade names, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), and Urethane Emulsion WBR-2120C and WBR-2122C (trade names, manufactured by Taisei Fine Chemical Co., Ltd.).

[0033] The cationic olefin resin has an olefin such as ethylene or propylene in its structural skeleton, and known resins can be appropriately selected and used. The cationic olefin resin may also be in an emulsion state dispersed in a solvent containing water or an organic solvent. Commercially available cationic olefin resins can be used, such as Arrowbase CB-1200 and CD-1200 (trade names, manufactured by Unitika Ltd.).

[0034] The cationic amine resin (cationic polymer) may be any resin having an amino group in its structure, and known resins may be appropriately selected and used. Examples include polyamine resins, polyamide resins, and polyallylamine resins. Polyamine resins are resins having amino groups in their main skeletons. Polyamide resins are resins having amide groups in their main skeletons. Polyallylamine resins are resins having a structure derived from allyl groups in their main skeletons.

[0035] Examples of cationic polyamine resins include Unisense KHE103L (hexamethylenediamine / epichlorohydrin resin, 1% aqueous solution with a pH of approximately 5.0, a viscosity of 20 to 50 (mPa·s), and a solids concentration of 50% by mass) and Unisense KHE104L (dimethylamine / epichlorohydrin resin, 1% aqueous solution with a pH of approximately 7.0, a viscosity of 1 to 10 (mPa·s), and a solids concentration of 20% by mass), both manufactured by Senka Corporation. Specific examples of commercially available cationic polyamine resins include FL-14 (manufactured by SNF Co., Ltd.), Arafix 100, 251S, 255, and 255LOX (manufactured by Arakawa Chemical Co., Ltd.), DK-6810, 6853, and 6885; WS-4010, 4011, 4020, 4024, 4027, and 4030 (manufactured by Seiko PMC Co., Ltd.), and Papiogen P-105 (manufactured by Senka Co., Ltd.). , Sumirez Resin 650 (30), 675A, 6615, SLX-1 (manufactured by Taoka Chemical 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.).

[0036] The polyamine resin also includes polyallylamine resin. Examples of the polyallylamine resin include polyallylamine hydrochloride, polyallylamine amidosulfate, allylamine hydrochloride-diallylamine hydrochloride copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine hydrochloride-dimethylallylamine hydrochloride copolymer, allylamine-dimethylallylamine copolymer, polydiallylamine hydrochloride, polymethyldiallylamine hydrochloride, polymethyldiallylamine amidosulfate, polymethyldiallylamine acetate, polydiallyldimethylammonium chloride, diallylamine acetate-sulfur dioxide copolymer, diallylmethylethyl Examples of the copolymers include ammonium ethyl sulfate-sulfur dioxide copolymer, methyldiallylamine hydrochloride-sulfur dioxide copolymer, diallyldimethylammonium chloride-sulfur dioxide copolymer, and diallyldimethylammonium chloride-acrylamide copolymer.

[0037] A plurality of types of these flocculants may be used. Furthermore, if at least one of polyvalent metal salts, organic acids, and cationic resins is selected from these flocculants, the flocculating action is more favorable, and therefore images of higher quality (especially with good color development) can be formed. Furthermore, it is more preferable to use polyvalent metal salts as the flocculant, and it is even more preferable to use calcium salts. In this way, the quality of the resulting images can be further improved.

[0038] The total content of the aggregating agent in the treatment liquid is, for example, 0.1% by mass or more and 20% by mass or less, preferably 1% by mass or more and 20% by mass or less, and more preferably 2% by mass or more and 15% by mass or less, relative to the total mass of the treatment liquid. Even when the aggregating agent is used in a solution or dispersion, the solids content is preferably within the above range. If the aggregating agent content is within the above range, the aggregating agent has sufficient ability to aggregate the components contained in the ink. Furthermore, if the aggregating agent content is within the above range, the solubility and dispersibility of the aggregating agent in the treatment liquid are improved, thereby improving the storage stability of the treatment liquid.

[0039] 1.2.1.(2) Water The treatment liquid used in the recording method according to this embodiment may be an aqueous treatment liquid containing water. An aqueous treatment liquid is a composition containing water as one of the main solvent components. In this way, recording can be performed with less odor and with a reduced environmental impact.

[0040] Water may be included as the main solvent component of the treatment liquid, and is a component that evaporates and dissipates upon drying. The water is preferably pure water or ultrapure water, such as ion-exchanged water, ultrafiltered water, reverse osmosis water, or distilled water, from which ionic impurities have been removed as much as possible. Furthermore, using water sterilized by ultraviolet irradiation or the addition of hydrogen peroxide is preferable, as this can prevent the growth of mold and bacteria when the ink is stored for a long period of time. The water content is preferably 45% by mass or more of the total amount of the treatment liquid. The upper limit is, for example, 99% by mass or less. It is more preferably 50% by mass or more and 98% by mass or less, and even more preferably 55% by mass or more and 95% by mass or less.

[0041] 1.2.1.(3) Surfactants The treatment liquid used in the recording method according to this embodiment may contain a surfactant. The surfactant is not particularly limited, but examples thereof include acetylene glycol surfactants, fluorine-based surfactants, and silicone-based surfactants. The surfactant adjusts the surface tension of the treatment liquid, thereby adjusting, for example, the wettability of the treatment liquid with the recording medium.

[0042] The acetylene glycol surfactant is not particularly limited, but examples thereof include Surfynol 104, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG-50, 104S, 420, 440, 465, 485, SE, SE-F, 504, 61, DF37, CT111, CT121, CT131, CT136, TG, GA, and DF110D (all trade names, manufactured by Air Products Japan Co., Ltd.), and Examples include Lulfin 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, and AE-3 (all trade names, manufactured by Nissin Chemical Industry Co., Ltd.), and Acetylenol E00, E00P, E40, and E100 (all trade names, manufactured by Kawaken Fine Chemicals Co., Ltd.).

[0043] As the fluorine-based surfactant, it is preferable to use a fluorine-modified polymer. An example is BYK-340 (trade name, manufactured by BYK Japan Co., Ltd.).

[0044] The silicone surfactant is not particularly limited, but a polysiloxane compound is preferred. The polysiloxane compound is not particularly limited, but for example, a polyether-modified organosiloxane is exemplified. Commercially available polyether-modified organosiloxanes include, for example, BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, and BYK-348 (all trade names, manufactured by BYK Japan KK), 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 (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), and Silface SAG503A and Silface SAG014 (all trade names, manufactured by Nissin Chemical Industry Co., Ltd.).

[0045] The surfactants may be used alone or in combination of two or more. When a 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.

[0046] 1.2.1.(4) Other ingredients The treatment liquid may contain components such as resin particles, organic solvents, surfactants, waxes, additives, preservatives, antifungal agents, rust inhibitors, chelating agents, viscosity modifiers, antioxidants, and antifungal agents, as long as they do not impair the function. These will be explained in order below.

[0047] (resin particles) The treatment liquid may contain resin particles. Resin particles may further improve the adhesion of an image formed by the ink adhered to a recording medium. Examples of resin particles include urethane-based resins, acrylic-based resins (including styrene-acrylic-based resins), fluorene-based resins, polyolefin-based resins, rosin-modified resins, terpene-based resins, polyester-based resins, polyamide-based resins, epoxy-based resins, vinyl chloride-based resins, vinyl chloride-vinyl acetate copolymers, and ethylene vinyl acetate-based resins. Among these, urethane-based resins, acrylic-based resins, polyolefin-based resins, and polyester-based resins are preferred. These resin particles are often handled in the form of an emulsion, but may also be in the form of a powder. Furthermore, the resin particles may be used alone or in combination of two or more types.

[0048] The glass transition temperature (Tg) of the resin particles is preferably -50°C or higher and 200°C or lower, more preferably 0°C or higher and 150°C or lower, and even more preferably 50°C or higher and 100°C or lower. 50°C or higher and 80°C or lower is particularly preferred. When the glass transition temperature (Tg) of the resin particles is within the above range, the durability and clogging resistance tend to be superior. The glass transition temperature is measured, for example, using a differential scanning calorimeter "DSC7000" manufactured by Hitachi High-Tech Science Corporation in accordance with JIS K7121 (Method for measuring transition temperature of plastics).

[0049] The volume average particle diameter of the resin particles is preferably 10 nm or more and 300 nm or less, more preferably 30 nm or more and 300 nm or less, even more preferably 30 nm or more and 250 nm or less, and particularly preferably 40 nm or more and 220 nm or less. The volume average particle diameter can be measured by the method described above.

[0050] The resin of the resin particles preferably has an acid value of 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. The lower limit of the acid value is 0 mgKOH / g or more, and 5 mgKOH / g or less. Preferably, the acid value is 10 mgKOH / g or more, and more preferably 10 mgKOH / g or more. Furthermore, 15 mgKOH / g or more is more preferable. In this case, image quality is excellent, which is preferable. Furthermore, when the acid value of the resin particles contained in the ink is in the above range or more, it is easy to make the viscosity increase rate of the ink composition of the ink described below in the range or more, which is preferable. The acid value can be measured by the method described above.

[0051] The content of 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, more preferably 1% by mass or less, particularly preferably 0.1% by mass or less, and may be zero, relative to the total mass of the treatment liquid. On the other hand, if resin particles are contained, 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.

[0052] The content of resin particles in the ink is preferably 0.5% by mass or more, more preferably 1% by mass or more, and even more preferably 3% by mass or more, based on the total mass of the ink, in terms of solid content, and is preferably 20% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less.

[0053] (organic solvent) The treatment liquid used in the recording method according to this embodiment may contain an organic solvent. The organic solvent is preferably water-soluble. One of the functions of the organic solvent is to improve the wettability of the treatment liquid with respect to the recording medium and to increase the moisturizing properties of the treatment liquid. The organic solvent can also function as a moisturizer and a penetrant.

[0054] Examples of organic solvents include esters, alkylene glycol ethers, cyclic esters, nitrogen-containing solvents, polyhydric alcohols, etc. Examples of nitrogen-containing solvents include cyclic amides and non-cyclic amides, etc. Examples of non-cyclic amides include alkoxyalkylamides.

[0055] 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.

[0056] The alkylene glycol ether may be a monoether or diether of alkylene glycol, and is preferably an alkyl ether. 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.

[0057] Examples of cyclic esters include cyclic esters (lactones) such as β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, and β-butyrolactone, as well as compounds in which the hydrogen atom of the methylene group adjacent to the carbonyl group of these cyclic esters is substituted with an alkyl group having 1 to 4 carbon atoms.

[0058] Examples of alkoxyalkylamides include 3-methoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, 3-methoxy-N,N-methylethylpropionamide, and 3-ethoxy-N,N-dimethylpropionamide. , 3-ethoxy-N,N-diethylpropionamide, 3-ethoxy-N,N-methylethylpropionamide, 3-n-butoxy-N,N-dimethylpropionamide, 3-n-butoxy-N,N-diethylpropionamide, 3-n-butoxy-N,N-methylethylpropionamide, and the like can be mentioned as examples.

[0059] 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 in terms of solubility of the flocculant and promotion of film formation of resin particles, which will be described later, and 2-pyrrolidone is particularly preferred.

[0060] It is also preferable to use a compound represented by the following general formula (1) as the alkoxyalkylamide.

[0061] R 1 -O-CH2CH2-(C=O)-NR 2 R 3 ···(1)

[0062] In the above formula (1), R 1 represents an alkyl group having 1 to 4 carbon atoms, and R 2 and R 3 each independently represents a methyl group or an ethyl group. The "alkyl group having 1 to 4 carbon atoms" can be a linear or branched alkyl group, such as 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 types.

[0063] The function of the nitrogen-containing solvent is, for example, to improve the surface drying and fixability of the treatment liquid applied to a low-absorbency recording medium. In particular, the compound represented by the above formula (1) is excellent in the ability to moderately soften and dissolve vinyl chloride resins. Therefore, the compound represented by the above formula (1) softens and dissolves the recording surface containing vinyl chloride resin, allowing the treatment liquid to penetrate into the interior of the low-absorbency recording medium. By the treatment liquid penetrating into the low-absorbency recording medium in this way, the treatment liquid is firmly fixed and the surface of the treatment liquid is easily dried. Therefore, the resulting image is likely to have excellent surface drying and fixability.

[0064] When a nitrogen-containing solvent is used in the treatment liquid, its content, relative to the total mass of the treatment liquid, preferably does not exceed 15 mass%, more preferably does not exceed 10 mass%, even more preferably does not exceed 5 mass%, further preferably does not exceed 2 mass%, and more preferably does not exceed 1 mass%. In particular, it is preferable that the processing liquid does not contain the above-mentioned amide solvents, which can further improve the graininess and abrasion resistance of the resulting image.

[0065] Examples of polyhydric alcohols include 1,2-alkanediols (e.g., alkanediols such as ethylene glycol, propylene glycol (also known as propane-1,2-diol), 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, and 1,2-octanediol), and polyhydric alcohols (polyols) other than 1,2-alkanediols (e.g., diethylene glycol, dipropylene glycol, 1,3-propanediol, and 1,3-butanediol (also known as 1,3-butylene glycol)). glycol), 1,4-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, glycerin, etc.

[0066] Examples of polyhydric alcohols include alkanediols and polyols. The alkanediols are preferably alkanediols having 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. 1,2-alkanediol, propylene glycol, etc. are preferred. 1,2-alkanediol is preferred.

[0067] Examples of polyols include alkanediols having 4 or less carbon atoms, intermolecular condensation products of hydroxyl groups of alkanediols, and alkanepolyols of triol or higher. The number of carbon atoms in the above alkanes is preferably 2 to 3. The number of hydroxyl groups in the polyol molecule is 2 or more, preferably 5 or less, more preferably 3 or less. When the polyol is an intermolecular condensation product as described above, the number of intermolecular condensations is 2 or more, preferably 4 or less, more preferably 3 or less. The polyhydric alcohols can be used alone or in combination of two or more.

[0068] Alkanediols and polyols can function primarily as penetrating solvents and / or moisturizing solvents, but alkanediols tend to have stronger penetrating solvent properties, while polyols tend to have stronger moisturizing solvent properties.

[0069] The treatment liquid may contain an organic solvent that is a polyhydric alcohol having a normal boiling point of 170°C or higher and 240°C or lower, which is preferable because it can further improve the graininess and abrasion resistance of the image.The treatment liquid more preferably contains an organic solvent that is a polyol having a normal boiling point of 170°C or higher and 240°C or lower.This is more preferable from the above-mentioned perspectives.

[0070] When the treatment liquid contains an organic solvent, the organic solvent may be used alone or in combination of two or more kinds, and the total content of the organic solvent relative to the total mass of the treatment liquid is, for example, 1 mass % or more and 50 mass % or less.

[0071] 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. 25 to 35% by mass is even more preferable. By having the organic solvent content within the above range, the balance between wetting and spreading properties and drying properties is even better, making it easier to form higher quality images.

[0072] It is also good and preferable that the content of the organic solvent, which is a polyol having a normal boiling point of 170° C. or more and 240° C. or less, falls within the above range. It is also good and preferable that the content of the organic solvent, which is a polyhydric alcohol having a normal boiling point of 170° C. or more and 240° C. or less, falls within the above range.

[0073] The treatment liquid preferably contains no more than 1% by mass, and more preferably no more than 0.5% by mass, of polyhydric alcohols having a normal boiling point above 280° C. It is also possible and preferred to set the content of organic solvents, including but not limited to polyhydric alcohols having a normal boiling point above 280° C., within the above range.

[0074] (wax) The treatment liquid may contain wax. Wax has the function of providing lubricity to ink images, which may reduce peeling of the images.

[0075] Examples of components constituting wax include plant and animal waxes such as carnauba wax, candy wax, beeswax, rice wax, and lanolin; paraffin wax, microcrystalline wax, polyethylene wax, oxidized polyethylene wax, and petroleum wax. Petroleum waxes such as Loratam; mineral waxes such as montan wax and ozokerite; synthetic waxes such as carbon wax, Hoechst wax, polyolefin wax, and stearic acid amide; natural and synthetic wax emulsions and blended waxes such as α-olefin-maleic anhydride copolymers, etc. can be used alone or in combination. Among these, polyolefin waxes (particularly polyethylene wax and polypropylene wax) and paraffin wax are preferred from the viewpoint of their superior effect of improving adhesion to flexible packaging films, which will be described later.

[0076] As the wax, commercially available products can be used as they are, such as Nopcoat PEM-17 (trade name, manufactured by San Nopco Ltd.), Chemipearl W4005 (trade name, manufactured by Mitsui Chemicals, Inc.), and AQUACER 515, 539, and 593 (all trade names, manufactured by BYK Japan K.K.).

[0077] Furthermore, since the recording method includes a heating step, etc., in order to prevent the wax from melting too much and its performance from decreasing, it is preferable to use a wax having a melting point of preferably 50°C or higher and 200°C or lower, more preferably 70°C or higher and 180°C or lower, and even more preferably 90°C or higher and 150°C or lower.

[0078] The wax may be supplied in the form of an emulsion or suspension. The wax content is, in terms of solid content, 0.1% by mass to 10% by mass, more preferably 0.5% by mass to 5% by mass, and even more preferably 0.5% by mass to 2% by mass, relative to the total mass of the treatment liquid. When the wax content is within the above range, the wax can exhibit its functions well. Furthermore, if the treatment liquid and at least one of the clear ink composition, ink composition, and ink composition described below contain wax, the function of imparting lubricity to an image can be more fully obtained.

[0079] (additives) The treatment liquid may contain additives such as ureas, amines, sugars, etc. Examples of ureas include urea, ethylene urea, tetramethyl urea, thiourea, 1,3-dimethyl-2-imidazolidinone, etc., and betaines (trimethylglycine, triethylglycine, tripropylglycine, triisopropylglycine, N,N,N-trimethylalanine, N,N,N-triethylalanine, N,N,N-triisopropylalanine, N,N,N-trimethylmethylalanine, carnitine, acetylcarnitine, etc.).

[0080] Examples of amines include diethanolamine, triethanolamine, triisopropanolamine, etc. Ureas and amines may function as pH adjusters. Examples of sugars include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, aldonic acid, glucitol (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, and maltotriose.

[0081] (others) The processing liquid used in the recording method according to this embodiment may further contain components such as preservatives, antifungal agents, rust inhibitors, chelating agents, viscosity adjusters, antioxidants, and antifungal agents, as required.

[0082] 1.2.1.(5) Physical properties of processing solution The treatment liquid used in the recording method of this embodiment has a surface tension at 25° C. of 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, in order to ensure appropriate wetting and spreading properties on the recording medium. The surface tension can be measured by wetting a platinum plate with the composition in an environment of 25°C using an automatic surface tensiometer CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).

[0083] The treatment liquid is more preferably applied to the recording medium by an inkjet method. In this case, the viscosity at 20°C is preferably 1.5 mPa·s or more and 15 mPa·s or less, more preferably 1.5 mPa·s or more and 7 mPa·s or less, and even more preferably 1.5 mPa·s or more and 5.5 mPa·s or less. When the treatment liquid is applied to the recording medium by an inkjet method, it is easy to efficiently form a predetermined treatment liquid application area on the recording medium.

[0084] 1.2.2. Method of applying processing liquid to recording medium The treatment liquid application step may be carried out by various methods such as a roller method, a spray method, a dipping method, an inkjet method, etc. In particular, the inkjet method, in which the treatment liquid is discharged from an inkjet head and applied to the recording medium, is preferred because it makes it easy to control the amount and position of application.

[0085] In this case, for example, the treatment liquid may be applied while scanning, which is a movement of the relative positions of the inkjet head and the recording medium, and any method may be used. Examples of inkjet methods include a serial method and a line method. In this way, a small device can efficiently print a variety of small quantities.

[0086] The amount of treatment liquid applied in the treatment liquid application process is 0.4 mg / inch 2 More preferably, it is 0.5 mg / inch or more. 2 More than 1.0 mg / inch is preferable.2 It is preferable that the concentration is 1.5 mg / inch or more. 2 More preferably, it is 2.0 mg / inch or more. 2 The above is more preferable. In this way, an image with even better filling properties can be obtained. It is also good and preferable that the maximum amount of treatment liquid applied in the treatment liquid application step is set to be equal to or greater than the above range.

[0087] The upper limit of the amount of treatment liquid to be applied in the treatment liquid application step is 5.0 mg / inch. 2 The recommended value is 3.0 mg / inch or less. 2 Below that, 2.5mg / inch 2 Less than 2.0 mg / inch 2 In particular, it is also preferable that the maximum amount of treatment liquid applied in the treatment liquid application step is within the above range.

[0088] If the amount of adhesion is greater than the above range, the resulting image is likely to have graininess, but even in this case, the effect of the recording method of this embodiment, that is, the ability to suppress graininess, is more pronounced.

[0089] Furthermore, when the treatment liquid application step is carried out by 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. The mass (ng) of the treatment liquid droplets in the treatment liquid application step, in terms of dot size (ng / dot), 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.

[0090] The ink may be applied to the recording medium in the ink application step after the treatment liquid is applied to the recording medium in the treatment liquid application step. In addition, the treatment liquid application step may apply the treatment liquid to the same scanning area as the scanning (pass) in which the ink composition is applied to the recording medium.

[0091] The treatment liquid application step is a step of applying a treatment liquid to a recording medium by mixing the ink composition applied to the recording medium by the ink application step with the treatment liquid. This is carried out so that the treatment liquid adhered to the recording medium in the adhering step can come into contact with and react with the treatment liquid on the recording medium.

[0092] 1.3.Ink application process In the ink deposition step, the ink composition is ejected from an inkjet head and deposited on a recording medium. The ink deposition step is performed on a recording medium supported on a recording medium support unit, and the surface temperature of the recording medium supported on the recording medium support unit and subjected to the ink deposition step is 27°C or higher and 38°C or lower. The surface temperature is preferably 28°C or higher and 35°C or lower, and more preferably 29°C or higher and 33°C or lower. When the surface temperature is higher than the above range, the reduction of unevenness in density and the like are more excellent, and when it is lower than the above range, the suppression of filling and pinholes, the clogging resistance, the reduction of condensation and the like are more excellent.

[0093] The surface temperature of the recording medium undergoing the ink deposition process is between 27°C and 38°C because it is heated by the heat of a heating mechanism, which will be described later. That is, because the recording medium support unit (platen), which will be described later, does not have a device for conductively heating the recording medium supported by the recording medium support unit, the surface temperature of the recording medium undergoing the ink deposition process is between 27°C and 38°C due to the heat of the heating mechanism. In other words, the surface temperature of the recording medium undergoing ink deposition is between 27°C and 38°C due to residual heat emitted from the heating mechanism. Details of the recording medium support unit will be described later.

[0094] 1.3.1. Ink composition The ink composition used in the recording method of this embodiment may contain the following components.

[0095] 1.3.1.(1) Colorants The ink composition may contain a coloring material. Examples of the coloring material include dyes and pigments. The coloring material may be, for example, a coloring material such as cyan, yellow, magenta, or black, or a white coloring material. Other examples of the coloring material include special color inks such as red, orange, blue, and green, and light color inks such as light magenta, light cyan, and gray.

[0096] The colorant may be either a dye or a pigment, or a mixture thereof. However, of dyes and pigments, it is more preferable to use a pigment. The pigment has excellent storage stability such as light resistance, weather resistance, and gas resistance, and from this viewpoint, it is preferable that the pigment is an organic pigment.

[0097] Specifically, examples of pigments that can be used include azo pigments such as insoluble azo pigments, condensed azo pigments, azo lakes, and chelate azo pigments; polycyclic pigments such as phthalocyanine pigments, perylene and perinone 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 can be used alone or in combination of two or more. Furthermore, a luster pigment can be used as a colorant.

[0098] Specific examples of pigments include, but are not limited to, the following:

[0099] Examples of black pigments include No. 2300, No. 900, MCF88, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, No. 2200B, etc. (all manufactured by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, Raven 700, etc. (all manufactured by Carbon Columbia), Rega1 400R, Rega1 330R, Rega1 660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1200, Monarch 1300, Monarch 1400, Monarch 1500, Monarch 1600, Monarch 1700, Monarch 1800, Monarch 1900, Monarch 2000, Monarch 2100, Monarch 2200, Monarch 2300, Monarch 2400, Monarch 2500, Monarch 2600, Monarch 2700, Monarch 2800, Monarch 2900, Monarch 3000, Monarch 3100, Monarch 3200, Monarch 3300, Monarch 3400, Monarch 3500, Monarch 3600, Monarch 3700, Monarch 3800, Monarch 3900, Monarch 4000, Monarch 4100, Monarch 4200, Monarch 4300, Monarch 4400, Monarch 4500, Monarch 4600, Monarch 4700, Monarch 4800, Monarch Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, etc. (manufactured by Cabot Corporation (CABOT JAPAN KK)), Color Black FW1, Color Black FW2, Color Black FW2V, Color Black FW18, Color Black FW200, Color B1ack S150, Color Black S160, Color Black S170, Printex 35, Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, and Special Black 4 (all manufactured by Degussa).

[0100] Examples of yellow pigments 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.

[0101] Examples of magenta pigments 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. Examples include 19, 23, 32, 33, 36, 38, 43, and 50.

[0102] Examples of cyan pigments include CI Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:34, 15:4, 16, 18, 22, 25, 60, 65, and 66, and CI Vat Blue 4 and 60.

[0103] Furthermore, pigments other than magenta, cyan, and yellow are not particularly limited, but examples thereof include CI Pigment Green 7, 10, CI Pigment Brown 3, 5, 25, 26, and CI Pigment Orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, and 63.

[0104] The pearl pigment is not particularly limited, but examples thereof include pigments having pearlescent or interference luster, such as titanium dioxide-coated mica, fish scale foil, and bismuth oxychloride.

[0105] The metallic pigment is not particularly limited, but examples thereof include particles of aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, copper, and the like, either alone or as an alloy.

[0106] Examples of white coloring materials include metal oxides, barium sulfate, calcium carbonate, and other metal compounds. Examples of metal oxides include titanium dioxide, zinc oxide, silica, alumina, and magnesium oxide. Furthermore, particles having a hollow structure may be used as the white coloring material, and known particles having a hollow structure may be used. Among the examples listed above, titanium dioxide is preferably used as the white coloring material from the viewpoint of good whiteness and abrasion resistance.

[0107] In addition, examples of dyes include direct dyes, acid dyes, food dyes, basic dyes, and reactive dyes. Various dyes that are usually used in ink jet recording, such as dyes, disperse dyes, vat dyes, soluble vat dyes, and reactive disperse dyes, can be used.

[0108] The colorant is preferably one that can be stably dispersed or dissolved in the dispersion medium, and may be dispersed using a dispersant as needed.

[0109] It is preferable that the colorant can be stably dispersed in the dispersion medium, and therefore a dispersant may be used for dispersion. Examples of dispersants include resin dispersants, and are selected from those that can improve the dispersion stability of the colorant in the ink composition. In addition, the colorant may be used as a self-dispersing pigment by modifying the surface of the pigment particles by oxidizing or sulfonating the pigment surface with, for example, ozone, hypochlorous acid, fuming sulfuric acid, or the like.

[0110] Examples of resin dispersants (dispersant resins) include (meth)acrylic resins and salts thereof such as poly(meth)acrylic acid, (meth)acrylic acid-acrylonitrile copolymer, (meth)acrylic acid-(meth)acrylic acid ester copolymer, vinyl acetate-(meth)acrylic acid ester copolymer, vinyl acetate-(meth)acrylic acid copolymer, and vinylnaphthalene-(meth)acrylic acid copolymer; styrene-(meth)acrylic acid copolymer, styrene-(meth)acrylic acid-(meth)acrylic acid ester copolymer, styrene-α-methylstyrene-(meth)acrylic acid copolymer, and styrene-α-methylstyrene-(meth)acrylic acid copolymer. Examples of suitable water-soluble resins include styrene-based resins such as acrylic acid-(meth)acrylic acid ester copolymers, styrene-maleic acid copolymers, and styrene-maleic anhydride copolymers, and salts thereof; urethane-based resins and salts thereof, which are polymeric compounds (resins) containing urethane bonds formed by the reaction of an isocyanate group with a hydroxyl group and may be linear and / or branched, and may have a crosslinked structure; polyvinyl alcohols; vinyl naphthalene-maleic acid copolymers and salts thereof; vinyl acetate-maleic acid ester copolymers and salts thereof; and vinyl acetate-crotonic acid copolymers and salts thereof. Among these, preferred are copolymers of a monomer having a hydrophobic functional group and a monomer having a hydrophilic functional group, and polymers composed of a monomer having both a hydrophobic and a hydrophilic functional group. The copolymers may be random copolymers, block copolymers, alternating copolymers, or graft copolymers. Among styrene-based resins, copolymers with (meth)acrylic monomers are also considered (meth)acrylic resins.

[0111] Commercially available styrene resin dispersants include, for example, X-200, X-1, X-205, X-220, and X-228 (manufactured by Seiko PMC Co., Ltd.), Nopcosperse (registered trademark) 6100 and 6110 (manufactured by San Nopco Ltd.), Joncryl 67, 586, 611, 678, 680, 682, and 819 (manufactured by BASF), DISPERBYK-190 (manufactured by BYK Japan KK), N-EA137, N-EA157, N-EA167, N-EA177, N-EA197D, N-EA207D, and E-EN10 (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.).

[0112] Commercially available acrylic resin dispersants include BYK-187, BYK-190, BYK-191, BYK-194N, and BYK-199 (manufactured by BYK-Chemie Co., Ltd.), Aron A-210, A6114, AS-1100, AS-1800, A-30SL, A-7250, and CL-2 (manufactured by Toagosei Co., Ltd.).

[0113] Furthermore, commercially available urethane 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 Chemi), and Borchi (registered trademark) Gen 1350 (manufactured by OMG Borschers).

[0114] The dispersant may be used alone or in combination of two or more. The total content of the dispersant is The dispersant content is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 0.5 parts by mass or more and 25 parts by mass or less, even more preferably 1 part by mass or more and 20 parts by mass or less, and even more preferably 1.5 parts by mass or more and 15 parts by mass or less, relative to 50 parts by mass of the white colorant. By making the dispersant content 0.1 parts by mass or more relative to 50 parts by mass of the colorant, the dispersion stability of the colorant can be further improved. Furthermore, by making the dispersant content 30 parts by mass or less relative to 50 parts by mass of the colorant, the viscosity of the resulting dispersion can be kept low.

[0115] Among the dispersants listed above, at least one selected from anionic dispersant resins is more preferred. In this case, the weight-average molecular weight of the dispersant is more preferably 500 or more. Furthermore, it is more preferably 5,000 or more and 100,000 or less, and even more preferably 10,000 or more and 50,000 or less.

[0116] The use of such a resin dispersant as a dispersant improves the dispersion and aggregation of the pigment, resulting in better dispersion stability and images of better image quality. Furthermore, the viscosity increase rate of the ink composition, which will be described later, can be easily increased by 5 times or more, which is preferable.

[0117] Anionic dispersant resins are resins that have anionic functional groups and exhibit anionic properties. Examples of the anionic functional groups include carboxyl groups, sulfo groups, and phosphate groups. Among these groups, carboxyl groups are more preferred.

[0118] The dispersant resin may or may not have an acid value, but preferably has an acid value of 5 mgKOH / g or more, or preferably has an acid value of 250 mgKOH / g or less. Furthermore, the acid value is more preferably 10 to 200 mgKOH / g, and even more preferably 15 to 150 mgKOH / g. Further, 20 to 100 mgKOH / g is more preferable, and 30 to 80 mgKOH / g is even more preferable. Furthermore, the lower limit is preferably 40 mgKOH / g or more, more preferably 50 mgKOH / g or more, particularly preferably 60 mgKOH / g or more, and even more preferably 70 mgKOH / g or more. Furthermore, 80 mgKOH / g or more is preferable. When the acid value is in the above range or more, the viscosity increase rate of the ink composition, which will be described later, can be easily increased by 5 times or more, which is preferable.

[0119] The acid value can be measured by neutralization potentiometric titration in accordance with JIS K 0070. As a titration device, for example, "AT610" manufactured by Kyoto Electronics Manufacturing Co., Ltd. can be used.

[0120] The content of the colorant is preferably 0.3% by mass to 20% by mass, more preferably 0.5% by mass to 15% by mass, based on the total mass of the ink composition. It is further preferably 1% by mass to 10% by mass, and even more preferably 2% by mass to 7% by mass. For white ink, the above ranges are preferred, and it is further preferably 5% by mass to 17% by mass, and even more preferably 8% by mass to 13% by mass.

[0121] When a pigment is used as the colorant, the volume average particle diameter of the pigment particles is preferably 10 nm to 300 nm, more preferably 30 nm to 250 nm, even more preferably 50 nm to 250 nm, and particularly preferably 70 nm to 200 nm. Furthermore, 80 nm to 150 nm is preferable. The volume average particle diameter of the colorant is measured in the initial state using the aforementioned method for determining the volume average particle diameter. A volume average particle diameter within the above range is preferable in that the desired colorant is easily available and the properties of the colorant can be easily improved.

[0122] 1.3.1.(2) Water The ink composition used in the recording method according to this embodiment is a water-based ink containing water. A water-based ink is a composition containing water as one of the main solvent components. This allows recording with less environmental impact and less odor. Water is used in the above-mentioned The water content and the like of the treatment liquid may be the same, and the explanation will be omitted.

[0123] 1.3.1.(3) Other ingredients The ink composition may contain components such as resin particles, organic solvents, surfactants, waxes, additives, preservatives, antifungal agents, rust inhibitors, chelating agents, viscosity modifiers, antioxidants, and antifungal agents.

[0124] The components of the ink composition, other than the colorant and the aggregating agent, are the same as those that may be used in the treatment liquid, and can be selected independently of the treatment liquid. These components may all be the same as those in the treatment liquid described above, and detailed explanations will be omitted by replacing "treatment liquid" with "ink composition."

[0125] When the ink composition contains an organic solvent, it is preferably 1% by mass or more relative to the total mass of the ink composition. It is more preferably 5% by mass to 40% by mass, more preferably 10% by mass to 35% by mass, and even more preferably 12% by mass to 30% by mass. It is more preferably 15 to 27% by mass, and even more preferably 20 to 25% by mass.

[0126] In this way, it is easier to both suppress nozzle clogging and improve image drying. When the ink composition contains an organic solvent, if the organic solvent content is within the above range, the reaction with the treatment liquid is accelerated, resulting in better reduction of unevenness in density, and the ink drying properties are improved, making it more preferable. On the other hand, if the organic solvent content is above the above range, the reaction with the reaction liquid is suppressed, resulting in better filling properties and better pinhole prevention, making it more preferable.

[0127] 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.

[0128] 1.3.1.(4) Physical properties of ink composition In order to ensure appropriate wetting and spreading properties on a recording medium, the ink composition used in the recording method of this embodiment preferably has a surface tension of 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 at 25° C. The surface tension can be measured by wetting a platinum plate with the composition at 25° C. using an automatic surface tensiometer CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).

[0129] The ink composition is applied to a recording medium by an inkjet method, and therefore the viscosity at 20°C is preferably 1.5 mPa·s or more and 15 mPa·s or less, more preferably 1.5 mPa·s or more and 7 mPa·s or less, and even more preferably 1.5 mPa·s or more and 5.5 mPa·s or less.

[0130] 1.3.2. Viscosity increase rate of ink composition The ink composition preferably exhibits a viscosity increase of at least 5 times when mixed with a 7% by mass aqueous solution of calcium formate at a mass ratio (ink composition: 7% by mass aqueous solution of calcium formate) of 10:1. This viscosity increase ensures sufficient coagulation of the components of the ink composition upon contact with the treatment liquid, and further improves the quality of the image formed with the ink composition. This further improves the uniformity of shading in the resulting image.

[0131] The "thickening rate" of the ink composition is defined as the increase in viscosity of the ink when mixed with a 7% by mass aqueous solution of calcium formate as follows: That is, the thickening rate is the rate of increase in viscosity when the ink and treatment liquid used in the recording method are mixed and stirred at a mass ratio of ink:treatment liquid of 10:1. The viscosity is measured at 20°C.

[0132] The viscosity increase ratio is the ratio of the viscosity after mixing to the viscosity before mixing. The viscosity increase ratio is, for example, between 0.5 and 10.0 times. Depending on the ink composition, the viscosity increase ratio may be less than 1.0 times, resulting in a decrease in viscosity, but this is still referred to as the viscosity increase ratio. Viscosity can be measured using a rheometer. When measuring viscosity, the mixed liquid is thoroughly stirred before a sample is taken.

[0133] The lower limit of the viscosity increase rate of the ink composition is preferably 2 times or more, more preferably 3 times or more, and even more preferably 5 times or more, more preferably more than 5 times, more preferably 5.5 times or more, even more preferably 6 times or more, and particularly preferably 7 times or more. Furthermore, 10 times or more is preferable. In this way, images of better quality can be formed.

[0134] On the other hand, the upper limit of the viscosity increase rate of the ink composition is not limited, but is preferably 20 times or less, more preferably 10 times or less, 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 rate of the ink composition is within the above range, the image quality, crack resistance, abrasion resistance, ejection stability, etc. are more excellent, which is preferable. Furthermore, the image quality of the obtained image is also excellent, and graininess in particular can be reduced.

[0135] The viscosity increase rate of the ink composition can be adjusted mainly by adjusting the type, content, etc. of the pigment (including the resin dispersant) and resin particles. In particular, adjusting the type, content, etc. of the pigment (including the resin dispersant) is easy to adjust and is therefore preferred.

[0136] 1.3.3. Method for applying ink composition to recording medium The ink deposition step is carried out by ejecting the ink from an inkjet head and depositing it on a recording medium. The ink deposition step is preferably carried out in a mode in which the ink composition is deposited while scanning, which moves the relative positions of the inkjet head and the recording medium, and may be carried out by any method. Examples of inkjet scanning methods include a serial method and a line method. In this way, small-volume, multi-type printing can be efficiently carried out using a small device.

[0137] In the ink application step, multiple types of ink compositions may be applied to the recording medium. For example, in the ink application step, a non-white ink containing a non-white colorant and a white ink containing a white colorant may be applied to the recording medium. Furthermore, in this case, the number of non-white inks may be multiple, and for example, cyan, magenta, yellow, black, and white ink compositions may be applied to the recording medium in the ink application step.

[0138] The maximum amount of ink composition applied during the ink application process is 1.5 mg / inch. 2 More preferably, it is 3.0 mg / inch or more. 2 More than 4.0 mg / inch is preferable. 2It is preferable that the concentration is 5.0 mg / inch or more. 2 More than 25 mg / inch is preferable. 2 Less than 20 mg / inch is preferred. 2 Less than 15 mg / inch is more preferable. 2 The following is even more preferred:

[0139] Furthermore, 11.0 mg / inch 2 Preferably, it is less than 10.0 mg / inch, more preferably 10.0 mg / inch 2 It is less than 9.0 mg / inch. 2 Less than 7.0 mg / inch is more preferable. 2 The following is more preferable: In this way, an image having even better filling properties can be obtained. The above-mentioned adhesion amount is the total ink adhesion amount of the water-based ink containing the coloring material used for recording.

[0140] Furthermore, the mass (ng) of the droplets of the ink composition in the ink application step is preferably 8 ng or less, more preferably 1 ng to 8 ng, even more preferably 1 ng to 7 ng, and even more preferably 2 ng to 6 ng. In terms of dot size (ng / dot), the mass (ng) of the droplets of the ink composition in the ink application step is preferably 8 ng / dot or less, more preferably 1 ng to 8 ng / dot, even more preferably 1 ng to 7 ng / dot, and even more preferably 2 ng / dot to 6 ng / dot.

[0141] In the ink application step, the ink is applied to the recording medium after the treatment liquid is applied to the recording medium in the treatment liquid application step. In addition, the ink application step may apply the ink composition to the same scanning area in the same scan (pass) as the scan in which the treatment liquid is applied to the recording medium.

[0142] 1.4.Transportation process In the conveying step, the recording medium that has been subjected to the treatment liquid application step and the ink application step is conveyed to a heating mechanism. The recording medium is conveyed by a standard method using rollers, guides, etc. The heating mechanism will be described later.

[0143] 1.5.Heating process 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 means (heating mechanism). The heating step is performed, for example, by a heater. This dries the resulting image and allows it to be fixed more sufficiently, so that, for example, the recorded matter can be made usable sooner.

[0144] The temperature that the recording medium heated by the heating mechanism reaches is not particularly limited, but can be set, for example, taking into consideration the Tg of the resin component that constitutes the resin particles contained in the recording material. When taking into consideration the Tg of the resin component that constitutes the resin particles and wax, it is advisable to set the temperature 5.0°C or more, preferably 10.0°C or more higher than the Tg of the resin component that constitutes the resin particles.

[0145] The surface temperature of the recording medium reached by heating in the heating step is preferably 30.0°C or higher and 120.0°C or lower, more preferably 40.0°C or higher and 100.0°C or lower, even more preferably 50.0°C or higher and 95°C or lower, and even more preferably 70°C or higher and 90°C or lower. The surface temperature of the recording medium reached by heating in the heating step is particularly preferably 80°C or higher. If the temperature of the recording medium is within this range, the resin particles and wax contained in the recorded matter can be formed into a film and flattened, and the resulting image can be dried and more fully fixed.

[0146] The time for which the recording medium is heated by the heating mechanism in the heating step is preferably from 1 to 40 seconds, more preferably from 3 to 25 seconds, and even more preferably from 5 to 20 seconds. Furthermore, it is more preferably from 9 to 15 seconds. In this way, a sufficiently dried image can be formed at high speed.

[0147] 1.6.Other processes The recording method of this embodiment may include the following aspects and steps.

[0148] 1.6.1.Blowing process An air blowing step may be carried out during the ink application step. In the ink application step, the ink composition is applied to the recording medium, and the surface temperature of the recording medium at that time is 27°C or higher and 38°C or lower. The air blowing step is carried out so as not to deviate from this temperature range. By doing so, the ink can be fixed more quickly, and an image of better quality can be formed.

[0149] The air blowing step can be carried out by means of blowing room temperature air or hot air onto the recording medium, for example, using a fan. The temperature of the air in the air blowing step is preferably adjusted so that the surface temperature of the recording medium is 27°C or higher and 38°C or lower. In particular, 40°C or lower is preferable, 38°C or lower is even more preferable, 35°C or lower is even more preferable, and 30°C or lower is even more preferable. Also, 10°C or higher is preferable, 15°C or higher is more preferable, 20°C or higher is even more preferable, and 25°C or higher is particularly preferable. It may be 27°C or higher.

[0150] The air speed in the air blowing step is preferably 1 m / s or more and 20 m / s or less, more preferably 2 m / s or more and 15 m / s or less, and even more preferably 3 m / s or more and 13 m / s or less. Furthermore, 5 m / s or more and 10 m / s or less is more preferable. This allows the ink to be fixed more quickly, resulting in the formation of images with better image quality.

[0151] The wind speed refers to the wind speed in the vicinity of the recording medium (the distance between the recording medium and the head), and is the maximum wind speed in the area where recording is possible on the recording medium on the platen. The wind temperature may be warm air, but room temperature air is preferable. The wind temperature should also be measured at the same position as the wind speed, and should be measured in a state where it is not affected by the heat of the platen.

[0152] 1.7. Recording Device An example of a recording apparatus that can be used in the recording method of this embodiment will be described below. The recording apparatus according to this embodiment is a recording apparatus that performs the above-mentioned recording method, and includes the treatment liquid, the ink composition, a treatment liquid application mechanism that performs the treatment liquid application step, the inkjet head, a transport mechanism that performs the transport step, the heating mechanism, and the recording medium support unit.

[0153] The heating mechanism of the recording apparatus of this embodiment has a portion located in a space extending in the direction perpendicular to the inkjet head from the area of ​​the recording medium supported by the recording medium support section where the ink composition can be adhered.

[0154] In the following example, a recording apparatus in which the treatment liquid deposition step is performed by ejecting the treatment liquid from an inkjet head and depositing it on the recording medium in the same manner as the ink deposition step will be exemplified.

[0155] The recording medium support unit, also referred to as a platen, does not include a device for conductively heating the recording medium supported by the recording medium support unit. In other words, the recording medium support unit does not include a member that serves as a heat source. Note that "conduction type" refers to a method in which heat is transferred by thermal transfer without the transfer of matter. Furthermore, "conduction type" refers to a method in which the recording medium support unit is heated by a heat source, and the heat is transferred from the recording medium support unit to the recording medium supported by the recording medium support unit, thereby heating the recording medium. The heat source is integrally configured with the recording medium support unit. Heat is then transferred from the heat source to the recording medium support unit, and then from the recording medium support unit to the recording medium supported by the recording medium support unit. For example, this is a platen heater. The recording medium support unit of this embodiment does not include a device for conductively heating the recording medium supported by the recording medium support unit.

[0156] If a device for conductively heating the recording medium supported by the recording medium support section is provided, it is not possible to simplify the recording apparatus or save space because a heat source is required, etc. In particular, such a device is provided integrally with the recording medium support section and tends to take up space below the recording medium support section.

[0157] Furthermore, such a device makes it difficult to control the temperature at which the recording medium is heated to an appropriate level. Therefore, in this embodiment, by not including such a device, the recording device can be simplified and space-saving, and the temperature at which the recording medium is heated can be easily stabilized.

[0158] Figure 1 is a front view showing a typical example of a serial type (serial method) recording device. In a serial type, the inkjet head and recording medium are moved relative to each other while performing a scan to eject ink from the inkjet head and deposit it on the recording medium, so that the ink deposits on the recording medium supported by the recording medium support unit. Recording progresses 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.

[0159] The device shown in Figure 1 is a lateral type recording device in which the carriage scanning direction and the recording medium transport direction are in the same axial direction. In other words, the carriage scanning direction and the recording medium transport direction do not intersect. This type of device is a type of serial type recording device.

[0160] In Figure 1, an XYZ Cartesian coordinate system with the Z axis as the vertical axis is also shown to clarify the relative positions of the various parts of the device. In the following explanation, the direction of each coordinate axis (arrow) will be referred to as the positive direction, and the opposite direction as the negative direction. The recording device shown in Figure 1 is also referred to as a lateral recording device, as the recording medium is transported in a direction along the axis of the scanning direction.

[0161] The recording device 100 includes a host device 200 that generates print data from 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 transporting the sheet S in a roll-to-roll manner.

[0162] As shown in Figure 1, the printer unit 300 has a main body case 1 that has a substantially rectangular parallelepiped shape. Inside the main body case 1 are a payout unit 2 that pays out the sheet S from a roll R1 around which the sheet S is wound, a printing chamber 3 that ejects ink onto the surface of the paid-out sheet S to perform printing, a drying unit 4 that dries the sheet S with the ink attached, and a winding unit 5 that winds up the dried sheet S into a roll R2.

[0163] More specifically, the interior of the main body case 1 is divided into upper and lower sections in the Z-axis direction by a flat base 6 arranged parallel to the XY plane (i.e., horizontally), with the upper side of the base 6 being the printing chamber 3. In approximately the center of the printing chamber 3, a platen 30 is fixed to the upper surface of the base 6. The platen 30 has a rectangular shape, and supports the sheet S from below with its upper surface, which is parallel to the XY plane. A recording unit 31 then prints on the surface of the sheet S supported on the platen 30.

[0164] Meanwhile, below the base 6, the unwinding unit 2, the drying unit 4, and the winding unit 5 are arranged. The unwinding unit 2 is arranged below the platen 30 in the negative direction of the X axis (diagonally downward left in FIG. 4), and includes a rotatable unwinding spindle 21. The sheet S is wound around this unwinding spindle 21 to support a roll R1. The winding unit 5 is arranged below the platen 30 in the positive direction of the X axis (diagonally downward right in FIG. 1), and includes a rotatable winding spindle 51. The sheet S is wound around this winding spindle 51 to support a roll R2. The drying unit 4 is arranged directly below the platen 30, between the unwinding unit 2 and the winding unit 5 in the X axis direction.

[0165] The sheet S fed from the feeding shaft 21 of the feeding section 2 passes through the printing chamber 3 and the drying section 4 in order while being guided by the rollers 71 to 77, and is then wound up on the winding shaft 51 of the winding section 5. The rollers 72 and 73 are arranged in a straight line (i.e., horizontally) in the X-axis direction with the platen 30 sandwiched between them, and the tops of the rollers 72 and 73 are positioned above the platen 30. The position of roller 72 is adjusted so that it is at the same height as the surface (the surface that supports sheet S). Therefore, sheet S wound around roller 72 moves horizontally (in the X-axis direction) while sliding on the upper surface of platen 30 until it reaches roller 73.

[0166] In the printing chamber 3, a recording unit 31 disposed above the platen 30 performs a printing process on a sheet S, which is a recording medium. This recording unit 31 prints an image on the surface of the sheet S by ejecting a treatment liquid and an ink composition onto the surface of the sheet S. A cartridge mounting section 8 is provided at the end of the printing chamber 3 in the negative direction of the X axis (the left end in FIG. 1), and a treatment liquid cartridge 81 that stores the above-mentioned treatment liquid and a plurality of ink cartridges 82 that store the above-mentioned ink composition are removably mounted in the cartridge mounting section 8. The recording unit 31 is capable of ejecting the treatment liquid supplied from the treatment liquid cartridge 81 and the ink composition supplied from the ink cartridges 82 onto the surface of the sheet S using an inkjet system.

[0167] FIG. 2 is a bottom view partially illustrating the configuration of the recording unit. In this example, the recording unit 31 will be described in detail with reference to FIGS. 1 and 2. The recording unit 31 includes a carriage 32, a flat support plate 33 attached to the underside of the carriage 32, and an inkjet head 34 for treatment liquid and an inkjet head 35 attached to the underside of the support plate 33. On the underside of the support plate 33, four inkjet heads 35 for ink and one inkjet head 34 for treatment liquid are aligned at equal pitches in the X-axis direction, and each inkjet head 34, 35 has a plurality of nozzles N (nozzle rows) aligned parallel to the Y-axis direction. The treatment liquid inkjet head 34 ejects treatment liquid from the nozzles N, and each of the four inkjet heads 35 for ink ejects ink of a different color from the nozzles N.

[0168] In this embodiment, the first ink composition is ejected from the inkjet head 35 for ink located next to the inkjet head 34 for treatment liquid, and the second ink composition is ejected from the inkjet head 35 for ink located farthest from the inkjet head 34 for treatment liquid.

[0169] The length in the Y-axis direction of the nozzle rows of the treatment liquid inkjet head 34 and the ink inkjet head 35 is preferably equal to or greater than the length in the Y-axis direction of the sheet S (recording medium). Inkjet heads having such lengths enable recording in one pass and are excellent in recording speed, but the amount of ink deposited is large, making bleeding unevenness more likely to occur. In contrast, the recording apparatus according to this embodiment uses the above-mentioned recording method, and therefore tends to be able to achieve excellent image quality (bleed unevenness) even when recording in one pass.

[0170] In Figure 2, when the nozzle row of the treatment liquid inkjet head 34 that ejects the treatment liquid is projected along the head movement direction (X-axis direction), it is arranged so that it has an overlapping portion in the nozzle row direction (Y-axis direction) with the nozzle row of the inkjet head 35 that ejects the ink. With such an arrangement, the treatment liquid application step and each ink application step in the above-mentioned recording method can be performed by scanning while moving the inkjet head for the treatment liquid and the inkjet head for the ink relative to the recording medium, and can be performed in a mode (simultaneous ejection) in which the treatment liquid and the ink composition are applied to the same scanned area during the same scan.

[0171] In Figure 2, the number of inkjet heads is five, but the number of inkjet heads may be one or more, for example, 7 to 20 or less. The number of inkjet heads is also the number of nozzle rows. An inkjet head is a unit that ejects one ink or treatment liquid, and is also the number of nozzle rows. The number of inkjet heads may also be the number of inks.

[0172] Returning to Figure 1, the explanation will continue. The carriage 32 of the recording unit 31 configured as described above is movable integrally with the support plate 33, the treatment liquid inkjet head 34, and the ink inkjet head 35. In other words, an X-axis guide rail 37 extending parallel to the X-axis direction is provided inside the printing chamber 3, and when the carriage 32 receives the driving force of the X-axis motor, it moves in the X-axis direction along the X-axis guide rail 37.

[0173] The recording unit 31 then moves (scans) a carriage 32 above the platen 30 in the X-axis direction (main scanning direction, scanning direction), while ejecting treatment liquid from the treatment liquid inkjet head 34 and ink from the inkjet head 35, depositing the treatment liquid and the ink composition in the same scanning area in the same scanning operation, thereby printing an image on the surface of the sheet S, which is stopped on the upper surface of the platen 30. As a result, a two-dimensional image for one frame is printed on the surface of the sheet S, the length of the nozzle row in the Y direction and the scanning distance in the X-axis direction. Furthermore, the coloring material of the ink that makes up the two-dimensional image is coagulated by the action of the treatment liquid and fixed to the surface of the sheet S.

[0174] The printing of one frame as described above is repeatedly performed while intermittently moving the sheet S in the X-axis direction. Specifically, the print area is a predetermined range that covers almost the entire upper surface of the platen 30. The print area is an area of ​​the recording medium supported by the platen where ink can be applied during recording. In other words, it is an area where recording can be performed, and if there is an image to be recorded in that area, ink is applied.

[0175] The printing area is also called the attachment area A. The printing area is the area of ​​the recording medium supported by the platen in the range in the X direction indicated by A in Figure 1. The length of the printing area in the X axis direction is length A. Length A is the length of attachment area A in the recording medium transport direction, and is the length in the X direction in the figure.

[0176] The printing area also has a predetermined length in the Y direction in Fig. 1. The range of the printing area in the Y direction is the range in the Y direction over which ink can adhere to the recording medium supported by the platen during recording, and is, for example, the range of the length in the Y direction of the nozzle row of the inkjet head.

[0177] Then, the sheet S is intermittently transported in the X-axis direction in units of a distance (intermittent transport distance) corresponding to the length of this printing area in the X-axis direction, and one frame is printed on the sheet S that stops on the top surface of the platen 30 during the intermittent transport.

[0178] In other words, when printing of one frame is completed on the sheet S stopped on the platen 30, the sheet S is transported in the X-axis direction by the intermittent transport distance, and the unprinted side of the sheet S stops on the platen 30. Next, printing of one new frame is performed on this unprinted side, and when this is completed, the sheet S is again transported in the X-axis direction by the intermittent transport distance. This series of operations is then executed repeatedly.

[0179] Recording one frame on a stopped recording medium may be performed in one pass as described above, or in two or more passes. When performing recording in two or more passes, the inkjet head may be moved in the Y direction between passes. This is preferable because it allows for increased recording resolution in the Y direction. 10 passes or less is preferable, and 6 passes or less is more preferable. The fewer the number of passes, the faster the recording speed, which is preferable.

[0180] When printing in one pass or two or more passes, the distance of one transport may be shorter than length A. For example, the distance of one transport may be length A / number of passes, and scanning and transport may be performed alternately.

[0181] In order to keep the sheet S stopped on the upper surface of the platen 30 flat during intermittent conveyance, the platen 30 may be provided with a mechanism for sucking the sheet S stopped on its upper surface. Specifically, the upper surface of the platen 30 has a large number of suction holes (not shown), and a suction unit 38 is attached to the lower surface of the platen 30. When the suction unit 38 operates, negative pressure is generated in the suction holes on the upper surface of the platen 30, and the sheet S is sucked to the upper surface of the platen 30. The suction unit 38 has, for example, a fan (not shown), and generates negative pressure in the suction holes.

[0182] While the sheet S is stopped on the platen 30 for printing, the suction unit 38 sucks the sheet S to keep it flat. On the other hand, when printing is completed, the suction unit 38 stops sucking the sheet S, allowing the sheet S to be transported smoothly.

[0183] In this embodiment, the platen 30 does not have a heat source such as a heater. In other words, the platen 30 does not have a device for conductively heating the recording medium supported by the platen 30. This simplifies the recording apparatus and saves space. It also makes it easier to install other mechanisms, such as the suction unit 38, below the platen 30.

[0184] In the recording apparatus according to this embodiment, a fan that blows air onto the recording medium from above may be provided in a location where the ink composition adheres, such as on the platen 30. This may promote drying of the image and result in better image quality. Examples of fans include a carriage fan located near the head and a ceiling fan that blows air from above. However, even with these configurations, the surface temperature of the recording medium when the ink adheres should be between 27°C and 38°C.

[0185] In this way, the sheet S that has received one frame of printing moves from the platen 30 to the drying unit 4 as the sheet S is intermittently transported. This drying unit 4 is capable of carrying out a post-heating step in which the treatment liquid and ink composition that have landed on the sheet S are completely dried using air heated for drying. The drying unit 4 may be configured as a conduction type, a convection type (air blowing), or a radiation type (such as an IR heater).

[0186] In the drying section 4, it is preferable to heat the sheet S so that the surface temperature it reaches is 30.0°C or higher and 120.0°C or lower, preferably 40.0°C or higher and 100.0°C or lower, more preferably 50.0°C or higher and 95°C or lower, and even more preferably 70°C or higher and 90°C or lower.

[0187] The sheet S that has been subjected to the drying process then reaches the winding section 5 as the sheet S is intermittently transported, and is wound up into a roll R2.

[0188] Here, the drying section 4 corresponds to the heating mechanism, and the platen 30 corresponds to the recording medium support section. Each roller is responsible for the transport process. Furthermore, the recording unit 31 includes an inkjet head. The platen 30 (recording medium support section) does not have a device for conductively heating the recording medium (sheet S) supported by the platen 30.

[0189] The drying section 4 (heating mechanism) is located in a space extending in the direction opposite the inkjet head (recording unit 31) from an attachment area A (printing area) on the recording medium (sheet S) supported by the platen 30 (recording medium support section) where the ink composition can be attached. In other words, the drying section 4 has a portion located in the space extending in the direction opposite the inkjet head from the attachment area A on the recording medium supported by the platen 30 where the ink composition can be attached. In other words, at least a portion of the drying section 4 is located within this space. This makes it possible to heat the recording medium in the attachment area A by using residual heat generated by the drying section 4.

[0190] It is preferable to have the drying section 4 located in more than half of the range (length A) in the recording medium transport direction of the space extending vertically from the adhesion area A in order to ensure more sufficient heating, and it is even more preferable to have the drying section 4 located in more than 70%.

[0191] The length of the drying unit 4 in the recording medium transport direction (the length in the X direction in Figure 1) is preferably equal to or greater than the length of one recording medium transport pass during recording. Furthermore, the length is preferably equal to or greater than half the length A of the adhesion area A in the recording medium transport direction, and more preferably equal to or greater than the length A of the adhesion area A in the recording medium transport direction. The length of the drying unit 4 is the length of the portion where the recording medium is heated in the drying unit 4.

[0192] It should be understood that even if the heating section 4 is positioned offset in the Y direction in the figure relative to the adhesion area A, it can be positioned so that it has a portion located in the space extending in the vertical direction on the opposite side of the adhesion area A from the inkjet head (recording unit 31).

[0193] The residual heat generated from the drying unit 4 may be transferred to the recording medium support unit through the air between the drying unit 4 and the recording medium support unit. Alternatively, a member may be provided between the drying unit and the recording medium support unit to secure them together, and the residual heat may be transferred to the recording medium support unit through this member.

[0194] In this embodiment, the recording medium support unit does not include a device other than the drying unit 4 for conductively heating the recording medium supported by the recording medium support unit.

[0195] The drying unit 4 is a unit where the recording medium is conveyed after the attachment process and heated, and is not originally a device for heating the recording medium supported by the recording medium support unit.

[0196] By using residual heat from the drying section 4 to heat the recording medium supported by the recording medium support section, the residual heat from the drying section 4 can be effectively utilized, which is excellent in terms of energy saving and image quality.

[0197] The time for which the recording medium is heated in the drying section is preferably 5 seconds or more, more preferably 8 seconds or more, and even more preferably 10 seconds or more. 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 preferable in terms of superior abrasion resistance and reduced thermal damage to the recording medium.

[0198] Fig. 3 is a front view showing a schematic diagram of another example of a serial recording device. In Fig. 3, components having the same functions as those in the recording device 100 described in Fig. 1 are given the same reference numerals, and detailed descriptions thereof will be omitted. Also, Fig. 3 shows only the configuration for explaining the arrangement of components, etc.

[0199] 3, in the recording apparatus 101, the platen 30 (recording medium support section) also does not have a device for conductively heating the recording medium (sheet S) supported by the platen 30. The drying section 4 (heating mechanism) has a portion outside the space extending in the direction opposite the inkjet head (recording unit 31) from an adhesion area A of the recording medium (sheet S) supported by the platen 30 (recording medium support section) where the ink composition can be adhered, and a portion inside the space, but also has a portion located in the space.

[0200] Fig. 4 is a front view showing a schematic diagram of another example of a serial recording device. In Fig. 4, components having the same functions as those in the recording device 100 described in Fig. 1 are given the same reference numerals, and detailed descriptions thereof will be omitted. Also, in Fig. 3, only the configuration for explaining the arrangement of components is shown.

[0201] As shown in FIG. 4, in the recording apparatus 102, the sheet S is dried in a drying unit 4 (heating mechanism). The sheet S is transported and passes through two transport paths within the drying unit 4. After passing through the drying unit 4 twice, the sheet S is transported between the platen 30 (recording medium support unit) and the drying unit 4 (heating mechanism), passes through transport path SB, and is taken up as a roll R2. Note that transport path SB is not the transport path in the transport step that transports the recording medium that has been subjected to the treatment liquid application step and the ink application step to the heating mechanism, but a transport path in the transport step may be provided between the platen 30 (recording medium support unit) and the drying unit 4 (heating mechanism) (not shown).

[0202] If a transport path for transporting the recording medium is provided between the recording medium support unit and the heating mechanism, as in the recording device 102 of Fig. 4, the heat generated by the heating mechanism can be used more effectively and the space within the device can be used more effectively. Also, if the heating mechanism is in two stages as in the recording device 102 of Fig. 4, secondary heating can be performed more sufficiently and the length of the recording device in the lateral direction (X direction) can be made more compact. Also, two or more stages of heating mechanisms may be located in the space on the opposite side of the inkjet head from the recording medium support unit, relative to the area of ​​the recording medium supported by the recording medium support unit where the ink deposition process is performed.

[0203] 4, the platen 30 (recording medium support section) also does not have a device for conductively heating the recording medium (sheet S) supported by the platen 30. The drying section 4 (heating mechanism) has a portion within a space extending in the direction opposite to the inkjet head (recording unit 31) from an adhesion area A on the recording medium (sheet S) supported by the platen 30 (recording medium support section) where the ink composition can be adhered.

[0204] In this way, by locating a heating mechanism below the platen and eliminating the need for a device for conductive heating of the platen, and instead using residual heat from the heating mechanism to warm the platen and perform heating at the platen, it is possible to obtain images of excellent quality. Although the temperature of the recording medium at the platen is relatively low, excellent image quality can be obtained when used in combination with the processing liquid, and by eliminating the need for a heat source in the platen, costs can be reduced. This is also effective in terms of saving space and energy, and because the temperature of the recording medium at the platen is relatively low, it is possible to reduce head clogging and the occurrence of condensation.

[0205] 1, 3, and 4 show the shortest distance D between the recording medium located in the recording medium support unit where ink is applied, and the recording medium where the heating process is performed in the heating mechanism. Distance D indicates the shortest distance in the vertical direction (Z direction) between the recording medium in the application 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 application area A between the recording medium in the application area A and the recording medium in the heating mechanism. If there are multiple drying units as in Figure 4, this is the distance closest to the recording medium support unit.

[0206] The shortest distance D between the recording medium located in the recording medium support section on which ink is applied and the recording medium on which the heating process is performed by the heating mechanism is preferably 100 mm to 1000 mm, more preferably 150 mm to 800 mm, even more preferably 200 mm to 700 mm, still more 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.

[0207] This arrangement provides a more appropriate spatial distance between the recording medium support unit and the heating mechanism, which helps reduce clogging of the head nozzles. It is also preferable because it makes it easier to keep the recording medium surface temperature in the attachment area A within a specified range.

[0208] As described above, the recording devices 100, 101, and 102 are supported by the recording medium support unit, and the ink deposition process is performed on the recording medium in a stationary state. In the case of a serial type, the head scans the recording medium stopped on the platen, and ink is deposited on the recording medium. This is preferable because the recording medium can be easily heated on the platen even at a relatively low temperature. In this case, the number of passes in the ink deposition process performed on the stationary recording medium is preferably 6 or less, more preferably 2 or less, and even more preferably 1.

[0209] The recording apparatus that can be used in the recording method of this embodiment may be a line-type recording apparatus. In the examples of the recording apparatus 100, recording apparatus 101, and recording apparatus 102 described above, the recording unit 31 scans the stationary recording medium to perform the ink deposition process. In contrast, in the case of a line-type recording apparatus, the recording medium is transported without stopping on the platen 30, and the fixed recording unit 31 ejects the treatment liquid, ink composition, etc., during the transport, to perform the ink deposition process.

[0210] Even in such a line-type recording apparatus, the drying unit 4 (heating mechanism) can be positioned within a space extending in the direction perpendicular to the inkjet head (recording unit 31) from the deposition area A, where the ink composition can be deposited, of the recording medium (sheet S) supported by the platen 30 (recording medium support unit). In the case of a line-type recording apparatus, the deposition area A is determined by the positions of the nozzles located upstream and downstream in the recording medium transport direction. For example, in FIG. 1, the recording unit 31 is fixed in the position shown in the figure, and ink is deposited on the recording medium while it is transported in the X direction relative to the fixed recording unit. In this case, the deposition 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.

[0211] Even in the line type, the recording medium can be heated as it passes over the platen.

[0212] Figure 5 is a perspective view schematically showing the periphery of an inkjet head and a recording medium support unit of yet another example of a serial recording device. In Figure 5, some components are omitted, such as components having the same functions as those of the recording device 100 described in Figure 1. In addition, in Figure 5, the drying unit, recording medium transport mechanism, etc. are also partially omitted.

[0213] The recording apparatus 1 includes an inkjet head 2, a carriage housing 9, a carriage main body 12, a platen 11, a carriage movement mechanism 13, a transport means 14, and a control unit CONT. The overall operation of the recording apparatus 1 is controlled by the control unit CONT.

[0214] The inkjet head 2 moves in the Y direction while scanning to eject ink from the nozzles of the inkjet head 2. In addition, a transport means 14 transports the recording medium M in the X direction. The inkjet head 2 is attached to the underside of a carriage. This is a recording device in which the scanning direction intersects with the transport direction.

[0215] In the example of the recording device in Figure 5, recording progresses by alternating scanning and transport. The deposition area A is an area of ​​the recording medium M supported by the platen 11 to which ink can be deposited during recording, and is an area that faces the inkjet head 2 when the inkjet head 2 scans. The inkjet head 2 may be the same as that shown in Figure 2, and is arranged such that the X direction in Figure 2 is the Y direction in Figure 5.

[0216] To be opposed to the inkjet head 2 means, strictly speaking, to be opposed to the nozzle row of the inkjet head 2 .

[0217] A drying unit (not shown) is located in a space extending downward in the Z direction from the plane of the adhesion area A. After the recording medium M is transported downstream in the X direction from the platen, it is transferred to a roller (not shown). The conveying direction is then changed downward in the Y direction, below the platen in the Y direction, and then the conveying direction is changed again to the upper right in the X direction as shown in the figure, and reaches the drying section. This is the same as in Figure 1.

[0218] In the recording apparatus example of FIG. 5, the length of the adhesion area A in the X direction is relatively short compared to the example of FIG. 1, but this example also has excellent image quality and clogging resistance.

[0219] According to the recording apparatus of the present embodiment, the recording medium support unit does not have a device for conductively heating the recording medium supported by the recording medium support unit, so the inkjet head is less likely to heat up, nozzle clogging can be reduced, and the recording method described above can be easily implemented. Furthermore, according to this recording apparatus, the use of a treatment liquid allows the ink to be fixed quickly, and it is possible to form images of good quality with good filling and little unevenness in density.

[0220] 1.8. Effects, etc. According to the recording method of this embodiment, the recording medium support unit does not have a device for conductively heating the recording medium supported by the recording medium support unit, so the inkjet head is less likely to heat up and nozzle clogging can be reduced. Furthermore, according to this recording method, because a treatment liquid is used, ink can be quickly fixed, and good filling and image quality with little unevenness in density can be formed.

[0221] In the recording method of this embodiment, by using a treatment liquid, it is possible to obtain image quality without relying too much on primary drying. If the temperature of the primary drying is high, there is a concern that the nozzles of the head may become clogged or that condensation may form on the nozzle surface of the head. However, in the recording method of this embodiment, it is possible to avoid the primary drying temperature being too high. In other words, in order to obtain excellent image quality, the recording method of this embodiment not only uses a treatment liquid, but also uses primary drying at a moderate temperature.

[0222] 2. Examples and Comparative Examples The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Hereinafter, "parts" and "%" are based on mass unless otherwise specified. The evaluations were carried out in an environment of a temperature of 25.0°C and a relative humidity of 40.0%, unless otherwise specified.

[0223] 2.1. Preparation of treatment liquid and ink composition The components were placed in a container so as to obtain the composition shown in Table 1, and mixed and stirred for 2 hours using a magnetic stirrer. The mixture was then filtered through a membrane filter with a pore size of 5 μm to obtain treatment liquids, non-white inks, and white inks according to the examples and comparative examples. The pigment used was the pigment dispersion prepared as follows:

[0224] The substances other than those listed by compound name in Table 1 are as follows:

[0225] Cationic polymer: "Catiomaster PD-7, polyamine resin (epichlorohydrin-amine derivative resin)" manufactured by Yokkaichi Synthetic Co., Ltd. Carbon black: No. 33 (Mitsubishi Chemical) Dispersant resin, Resin C (anionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 90) Dispersant resin, Resin A (anionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 40) Dispersant resin, resin B (nonionic): acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 0) Resin particles, styrene acrylic A: See below (high cohesiveness) Resin particles, styrene acrylic B: See below (low cohesion) Wax, polyethylene: Nopcoat PEM-17 (product name, manufactured by San Nopco Ltd.) Surfactant: Silicone surfactant "BYK348" manufactured by BYK 1,2-HD: 1,2-hexanediol

[0226] (Resin particles: Preparation of styrene acrylic resin B) 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. The surfactant used for emulsion polymerization was Newcol NT-30 (manufactured by Nippon Nyukazai Co., Ltd.), and the amount used was 2 parts by mass, based on 100 parts by mass of the total amount of monomers.

[0227] (Resin particles: Preparation of styrene acrylic A) Resin emulsion A (acid value 30 mgKOH / g) was obtained in the same manner as above except for changing the monomer composition. The surfactant for emulsion polymerization was 1 part by mass per 100 parts by mass of the total amount of monomers.

[0228] (Preparation of pigment dispersion) <White pigment dispersion using resin A> First, 12 parts by weight of Resin A was added as a resin dispersant to 155 parts by weight of ion-exchanged water containing 0.1 parts by weight of 30% aqueous ammonia solution (neutralizer). 40 parts by weight of titanium dioxide (CI Pigment White 6), a white pigment, was added and dispersed in a ball mill with zirconia beads for 10 hours. Subsequently, the mixture was centrifuged to remove impurities such as coarse particles and dust, and the concentration of the white pigment was adjusted to 20% by weight, yielding a white colorant dispersion. The average particle size of the white pigment was 350 nm.

[0229] <White pigment dispersion using resin B> A white colorant dispersion was obtained in the same manner as above, except that Resin B was used as the resin dispersant. The particle size of the white pigment was 350 nm on average.

[0230] <Non-white pigment dispersion using Resin C> 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 resin dispersant added was such that the mass ratio of resin dispersant to pigment was the mass ratio shown in Table 1. The average particle diameter of the pigment was 60 nm.

[0231] 2.2.Evaluation Method 2.2.1. Thickening rate The "viscosity increase [times] when mixed at a mass ratio of 10:1 (ink: 7% by mass calcium formate aqueous solution)" in Table 1 is the viscosity increase when each ink is mixed with a 7% by mass calcium formate aqueous solution at a mass ratio of 10:1, stirred for 1 minute, and then measured using a rheometer (MCR302 / Anton Paar) at 25°C and a shear rate of 200 s -1 When the viscosity of the mixed liquid was measured under the conditions of 1. to 3., the viscosity of the mixed liquid after mixing was multiplied by the viscosity of the ink before mixing. When measuring the viscosity of the mixed liquid, a sample was taken from the mixed liquid that had been thoroughly stirred.

[0232] 2.2.2. Recording test A modified SurePress L-4733A digital label printer was filled with ink and processing liquid, and each component was arranged as shown in Figure 1. A serial recording device was used. 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.

[0233] The nozzle density of the recording head was 1200 dpi, and the recording resolution was based on 1200 x 1200 dpi. The number of droplets per pixel was adjusted so that the deposition amount would be the value in each test below. The mass of the treatment liquid droplet was 3 ng, and the mass of the ink droplet was 7 ng. Air was blown from above the platen toward the recording medium using a blower mechanism. The air temperature was 25°C and the air speed was as shown in the table.

[0234] The time (residence time) that a certain portion of the recording medium was heated in the drying section is shown in the table.

[0235] In the table, examples in which the heater is located below the platen include a portion of the drying unit located within the space extending vertically downward from the adhesion area A. In examples in which the heater is not located, the drying unit is located completely to the right in the X direction from the space extending vertically downward from the adhesion area A.

[0236] The distance in the Y direction between the recording medium in the adhesion area A and the recording medium in the drying area is shown in the table. In some cases, this distance was changed.

[0237] The examples in which the platen does not have a heater are examples in which there is no device for conductively heating the recording medium supported by the platen, and are indicated as "none" in the table.

[0238] The number of printing passes is also listed in the table. In all examples, the transport distance for one pass was the length A in the X direction. In the two-pass example, the recording medium was not transported during the second pass, and was transported after the second pass. The amount of ink, etc., deposited was the same as in the one-pass example, with half of the amount deposited being deposited in each of the two passes. The same applies to examples with two or more passes.

[0239] The number of passes is the number of passes per ink, and when the ink was passed, the treatment liquid was also applied in the same pass. Also, in the example using white ink, the white ink was applied first using the number of passes shown in the table, and then the white ink was applied in the same pass as shown in the table. Half of the treatment liquid was applied in the same pass as the white ink, and the remaining amount was applied in the same pass as the non-white ink. The recording medium was not transported during this time.

[0240] 2.2.3. Image Filling and Pinhole Evaluation In the example of treatment liquid + non-white ink, the following ejection amounts were used. Processing liquid 1.5mg / inch 2 Non-white ink 7.0mg / inch 2 In the example of treatment liquid + white ink + non-white ink, the following amounts were applied. Processing liquid 1.5mg / inch 2 White ink 7.0mg / inch 2 Non-white ink 3.0mg / inch 2 The solid image area of ​​the obtained recorded matter was visually observed under a fluorescent lamp and evaluated according to the following criteria. The results are shown in Tables 2 to 4. A: There are no unfilled areas or pinholes. B: There are some unfilled areas and pinholes visible. C: Unfilled areas and pinholes are clearly visible.

[0241] 2.2.4. Evaluation of image shading unevenness In the example of treatment liquid + non-white ink, the following ejection amounts were used. Processing liquid 1.5mg / inch 2 Non-white ink 9.0mg / inch 2 In the example of treatment liquid + white ink + non-white ink, the following amounts were applied. Processing liquid 1.5mg / inch 2 White ink 9.0mg / inch 2 Non-white ink 5.0mg / inch 2 The solid image area of ​​the obtained recorded matter was visually observed under a fluorescent lamp and evaluated according to the following criteria. The results are shown in Tables 2 to 4. A: There is no unevenness in the shade. B: Some unevenness in shade is visible. C: Significant unevenness in shading is visible. D: The unevenness in shading is obvious, and the ink has smeared around the outline of the pattern, making it non-linear.

[0242] 2.2.5. Evaluation of clogging After printing continuously for one hour under the recording test conditions, suction cleaning was performed to restore non-ejecting nozzles and then a nozzle inspection was performed. Each cleaning was performed by discharging 1 cc of ink from the nozzle row. The results were evaluated according to the following criteria and are shown in Tables 2 to 4. A: All nozzles recovered within one cleaning B: All nozzles recovered within three cleanings C: Some nozzles do not recover after 4 cleanings

[0243] 2.2.6. Evaluation of Condensation on the Nozzle Surface For each ink nozzle row, image recording was performed continuously for one hour under the conditions shown in the table, and this was repeated three times (for a total of 3 hours). After recording was completed, the nozzles of the ejection nozzle group were inspected and the nozzle surface was observed. If there was no ejection or the ink flight deflection occurred for more than half the distance between adjacent nozzles, it was deemed to be an ejection defect. An evaluation was made as to whether or not ink flight deflection occurred due to contact with condensation. The evaluation was based on the following criteria, and the results are shown in Tables 2 to 4. A: No condensation on the nozzle surface. No nozzles with ejection problems. B: A small amount of condensation occurs on the nozzle surface. The number of nozzles with ejection problems is 3% or less. C: Condensation was observed on the nozzle surface. The number of nozzles with ejection problems exceeded 3%.

[0244] 2.2.7. Evaluation of abrasion resistance Recorded materials were used under the same conditions as those used to evaluate unevenness in density. The recorded area was rubbed 50 times with a plain woven cloth moistened with water using a Gakushin-type abrasion resistance tester (load 500 g), and the degree of ink peeling was visually observed. Evaluation was based on the following criteria, and the results are shown in Tables 2 to 4. A: Peeling is less than 10% of the evaluation area B: Peeling is more than 10% of the evaluation area

[0245] 2.3.Evaluation Results Looking at Tables 2 to 4, it can be seen that the results for each example, in which the ink composition was a water-based ink composition containing a colorant, the ink deposition process was carried out on a recording medium supported by a recording medium support unit, the recording medium support unit did not have a device for conductively heating the recording medium, the heating mechanism had a portion located in a space extending in the linear direction on the opposite side of the inkjet head from the area of ​​the recording medium supported by the recording medium support unit where the ink composition could be deposited, and the surface temperature of the recording medium supported by the recording medium support unit and subjected to the ink deposition process was 27°C or higher and 38°C or lower, showed good image quality (filling, pinholes, uneven shading) and little clogging.

[0246] Although not shown in the table, when the recording device in Figure 1 was modified into a line-type recording device as described above and recording was performed in the same manner as in the examples, similarly excellent evaluation results were obtained. Furthermore, when the recording device in Figure 1 was modified into a recording device that was heated twice in the drying section as shown in Figure 4, the abrasion resistance tended to be even better.

[0247] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations that replace non-essential parts of the configurations described in the embodiments. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations that add publicly known technology to the configurations described in the embodiments.

[0248] The following can be derived from the above-described embodiment and modifications.

[0249] The recording method is a treatment liquid applying step of applying a treatment liquid containing a flocculant to a recording medium; an ink deposition step of ejecting the ink composition from an inkjet head and depositing it on a recording medium; a conveying step of conveying the recording medium, which has been subjected to the treatment liquid applying step and the ink applying step, to a heating mechanism; a heating step of heating the recording medium conveyed by the conveying step with the heating mechanism; and the ink composition is a water-based ink composition containing a colorant, the ink deposition step is performed on a recording medium supported by a recording medium support unit, the recording medium support does not include a device for conductively heating a recording medium supported by the recording medium support; the heating mechanism has a portion located in a space extending in a direction perpendicular to the ink jet head from a region of the recording medium supported by the recording medium support unit to which the ink composition can be attached, and on a side opposite to the ink jet head; The surface temperature of the recording medium supported by the recording medium support unit and subjected to the ink deposition step is 27°C or higher and 38°C or lower.

[0250] According to this recording method, the recording medium support unit does not have a device for conductively heating the recording medium supported by the recording medium support unit, so the inkjet head is less likely to heat up and nozzle clogging can be reduced. Furthermore, according to this recording method, the use of a treatment liquid allows the ink to be fixed quickly, and it is possible to form images of good quality with good filling and little unevenness in density.

[0251] In the above recording method, The shortest distance between the recording medium positioned in the recording medium support section and on which ink is applied and the recording medium on which the heating step is performed by the heating mechanism may be 200 mm or more and 700 mm or less.

[0252] According to this recording method, the spatial distance between the recording medium support unit and the heating mechanism is more appropriate, which makes it easier to reduce nozzle clogging.

[0253] In the above recording method, The ink application step may include a step of blowing air.

[0254] According to this recording method, the ink can be fixed more quickly, and an image of better quality can be formed.

[0255] In the above recording method, The air velocity in the air blowing step may be 2 m / s or more and 15 m / s or less.

[0256] According to this recording method, the ink can be fixed more quickly, and an image of better quality can be formed.

[0257] In the above recording method, The ink deposition step may be performed on the recording medium that is supported by the recording medium support section and is in a stationary state.

[0258] In the above recording method, The number of passes in the ink application step may be six or less.

[0259] In the above recording method, The flocculant may be selected from polyvalent metal salts.

[0260] According to this recording method, it is possible to form images of better quality.

[0261] In the above recording method, The ink composition may have a viscosity increase ratio of 5 times or more when mixed with an aqueous calcium formate solution in a mass ratio (ink composition:aqueous solution) of 10:1.

[0262] According to this recording method, it is possible to form images of better quality.

[0263] In the above recording method, The ink composition may include a non-white ink containing a non-white colorant and a white ink containing a white colorant.

[0264] In the above recording method, The time period during which the recording medium is heated by the heating mechanism may be 3 seconds or more and 25 seconds or less.

[0265] According to this recording method, a sufficiently dried image can be formed at high speed.

[0266] In the above recording method, A transport path for transporting the recording medium may be provided between the recording medium support unit and the heating mechanism.

[0267] According to this recording method, the heat generated by the heating mechanism can be used more effectively.

[0268] In the above recording method, The ink composition may contain an organic solvent in an amount of 10% by mass or more and 35% by mass or less.

[0269] The recording device A recording device that performs any one of the above recording methods, the treatment liquid; the ink composition; a treatment liquid applying mechanism that performs the treatment liquid applying step; the inkjet head; a conveying mechanism that performs the conveying step; the heating mechanism; The recording medium support portion.

[0270] With this recording device, the recording medium support unit does not have a device for conductively heating the recording medium supported by the recording medium support unit, so the inkjet head is less likely to heat up and nozzle clogging can be reduced.In addition, with this recording device, the use of a treatment liquid allows the ink to be fixed quickly, and it is possible to form images of good quality with good filling and little unevenness in density. [Explanation of symbols]

[0271] 1...main body case, 2...feeding section, 9...carriage housing, 12...carriage main body, 13...carriage movement mechanism, 14...transport means, 21...feeding shaft, 3...printing chamber, 30, 11...platen, 31...recording unit, 32...carriage, 33...support plate, 34...treatment liquid inkjet head, 35...ink inkjet head, 37...X-axis guide rail, 38...suction section, 39...heater, 4...drying section, 5...winding section, 51...winding shaft, 6...base, 71-77...rollers, 8...cartridge mounting section, 81...treatment liquid cartridge, 82...ink cartridge, 100, 101, 102...recording device, 200...host device, 210...printer driver, 230...communication control section, 240...monitor, 300...printer section, 400...printer control section, R1, R2...roll, S...sheet, A...adhesion area, D...distance

Claims

1. a treatment liquid applying step of applying a treatment liquid containing a flocculant to a recording medium; an ink deposition step of ejecting the ink composition from an inkjet head and depositing it on a recording medium; a conveying step of conveying the recording medium, which has been subjected to the treatment liquid applying step and the ink applying step, to a heating mechanism; a heating step of heating the recording medium conveyed by the conveying step with the heating mechanism; and the ink composition is a water-based ink composition containing a colorant, the ink deposition step is performed on a recording medium supported by a recording medium support unit, the recording medium support does not include a device for conductively heating a recording medium supported by the recording medium support; the heating mechanism has a portion located in a space extending in a direction perpendicular to the ink jet head from a region of the recording medium supported by the recording medium support unit to which the ink composition can be attached, and on a side opposite to the ink jet head; A recording method in which the surface temperature of the recording medium supported by the recording medium support section and subjected to the ink deposition step is 27°C or higher and 38°C or lower.

2. In claim 1, A recording method, wherein the shortest distance between the recording medium positioned in the recording medium support section and subjected to ink deposition and the recording medium subjected to the heating step by the heating mechanism is 200 mm or more and 700 mm or less.

3. In claim 1, A recording method, wherein an air blowing step is carried out in the ink applying step.

4. In claim 2, The recording method, wherein the air velocity in the air blowing step is 2 m / s or more and 15 m / s or less.

5. In claim 1, The recording method, wherein the ink deposition step is performed on the recording medium that is supported by the recording medium support section and is in a stationary state.

6. In claim 1, The number of passes in the ink application step is 6 or less.

7. In claim 1, A recording method wherein the aggregating agent is selected from polyvalent metal salts.

8. In claim 1, The ink composition has a viscosity increase ratio of 5 times or more when mixed with an aqueous calcium formate solution in a mass ratio (ink composition:aqueous solution) of 10:

1.

9. In claim 1, The recording method, wherein the ink composition comprises a non-white ink containing a non-white coloring material and a white ink containing a white coloring material.

10. In claim 1, The time for which the recording medium is heated by the heating mechanism is 3 seconds or more and 25 seconds or less. Recording method.

11. In claim 1, A recording method, wherein a transport path for transporting the recording medium is provided between the recording medium support unit and the heating mechanism.

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

13. A recording apparatus for performing the recording method according to any one of claims 1 to 12, the treatment liquid; the ink composition; a treatment liquid applying mechanism that performs the treatment liquid applying step; the inkjet head; a conveying mechanism that performs the conveying step; the heating mechanism; a recording device having the recording medium support section.

Images