Recording method and recording device

Abstract

This invention provides a recording method and apparatus that offer excellent nozzle clogging recovery, image quality, and whitening reduction in printed materials. The recording method includes a processing liquid adhesion step and an ink adhesion step. The processing liquid adhesion step and the ink adhesion step are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. The same scan is used to adhere the processing liquid and ink composition to the same scanned area. The coagulant is a calcium salt with a content of 0.35 mol / kg or less relative to the total mass of the processing liquid. In the processing liquid adhesion step, the maximum value of calcium salt adhesion in the area of ​​the recording medium where the processing liquid and ink composition are adhered is within the range of 0.6 μmol / inch. 2 The following describes an air supply process for supplying air to the recording medium in the liquid coating process and the ink coating process.

Description

Technical Field

[0001] This invention relates to a recording method and a recording apparatus. Background Technology

[0002] Inkjet recording methods have achieved rapid development in various aspects, enabling the recording of high-resolution images with relatively simple devices. Among these developments, research is underway on recording methods that utilize processing solutions to reduce and fix the ink's fluidity as early as possible, thereby achieving superior image quality. Particularly for low-absorbency or non-absorbent recording media, where ink droplets are difficult to absorb, they sometimes mix and cause uneven bleeding, necessitating further investigation into the use of processing solutions.

[0003] In addition, in the case of using processing fluid for recording in serial or landscape printers, from the viewpoint of improving recording speed and miniaturizing the device, a recording method has been studied in which the ink-ejecting printhead and the processing fluid-ejecting printhead are arranged laterally in the scanning direction, so that the ink and processing fluid are simultaneously ejected in the same scanning area.

[0004] For example, Patent Document 1 discloses a recording method in which ink and processing liquid are simultaneously sprayed onto the same scanning area using the same scan.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-32600 Summary of the Invention

[0008] The technical problem that the invention aims to solve

[0009] However, in recording methods that use the same scan to attach ink and processing liquid to the same scan area, there is still a lack of excellence in terms of nozzle clogging recovery, image quality, and whitening reduction of printed matter.

[0010] Technical solutions for solving technical problems

[0011] One embodiment of the recording method involved in this invention is a recording method comprising:

[0012] The processing liquid adhesion process involves ejecting a processing liquid containing a coagulant from an inkjet head, causing it to adhere to the recording medium; and

[0013] The ink adhesion process involves ejecting a water-based ink composition containing coloring materials from an inkjet head, allowing it to adhere to the recording medium.

[0014] The processing liquid adhesion process and the ink adhesion process are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium.

[0015] Using the same scan, the processing liquid and the ink composition are adhered to the same scan area.

[0016] The coagulant is a calcium salt.

[0017] The content of the calcium salt relative to the total mass of the treatment solution is less than 0.35 mol / kg.

[0018] In the processing liquid adhesion step, the maximum value of the calcium salt adhesion amount in the region of the recording medium where the processing liquid and the ink composition are adhered is in the range of 0.6 μmol / inch. 2 the following,

[0019] The processing liquid adhesion process and the ink adhesion process include an air supply process for supplying air to the recording medium.

[0020] One aspect of the recording device involved in this invention is that,

[0021] A recording device that records on the recording medium using one of the recording methods described above.

[0022] It comprises the processing liquid, the ink composition, the inkjet head for the processing liquid, and the inkjet head for the ink. Attached Figure Description

[0023] Figure 1 It is a schematic schematic cross-sectional view of a serial inkjet recording device.

[0024] Figure 2 This is a perspective view showing an example of the structure around the carriage of a serial inkjet recording device.

[0025] Figure 3 This is a schematic diagram showing an example of an inkjet head configuration.

[0026] Figure 4 This is a schematic diagram showing an example of an inkjet head configuration.

[0027] Figure 5 This is a schematic diagram showing an example of an inkjet head configuration.

[0028] Figure 6 This is a front view schematically illustrating an example of a horizontal recording device.

[0029] Figure 7 It is a bottom view that partially shows the structure of the recording unit of a horizontal recording device.

[0030] Figure 8 This is a diagram (Table 1) showing an example of the composition of the treatment solution.

[0031] Figure 9 This is a diagram (Table 2) showing an example of the composition of an ink composition.

[0032] Figure 10 This is a graph (Table 3) showing examples of recording methods and evaluation results.

[0033] Figure 11 This is a graph showing examples of recording methods and evaluation results (Table 4).

[0034] Explanation of reference numerals in the attached figures

[0035] 19: Inkjet recording device; 29: Inkjet head (29a: inkjet head for processing liquid; 29b: inkjet head for ink); 391: IR heater; 49: Impression plate heater; 59: Heater; 69: Cooling fan; 79: Preheater; 89: Ventilation fan; 99: Carriage; 119: Impression plate; 129: Cartridge; 139: Carriage moving mechanism; 149: Transport unit; CONT: Control unit; MS: Main scanning direction; SS: Sub-scanning direction; M: Recording medium; 100: Recording device; 200: Main unit; 210: Printer driver; 230: Communication control unit; 240: Monitor; 300: Printer section; 400: Printer control section; 1: Main housing; 2: Feeding section; 9: Carriage frame; 12: Carriage main body; 13: Carriage moving mechanism; 14: Transport unit; 21: Feeding shaft; 3: Printing chamber; 30, 11: Impression plate; 31: Recording unit; 32: Carriage; 33: Support plate; 34: Inkjet head for processing fluid; 35: Inkjet head for ink; 37: X-axis guide rail; 38: Suction section; 39: Heater; 4: Drying section; 5: Take-up section; 51: Take-up shaft; 6: Base; 71-77: Rollers; 8: Cartridge mounting section; 81: Processing fluid cartridge; 82: Ink cartridge; R1, R2: Rollers; S: Sheet. Detailed Implementation

[0036] The embodiments of the present invention will now be described. The embodiments described below illustrate examples of the present invention. The present invention is not limited to the following embodiments, and includes various modifications implemented without changing the spirit of the invention. It should be noted that all structures described below are not necessarily essential structures of the present invention.

[0037] In this specification, the numerical range indicated by “~” refers to the range encompassed by the values ​​recorded before and after “~” as the lower and upper limits.

[0038] 1. Recording Method

[0039] One embodiment of the present invention relates to a recording method comprising: a processing liquid adhesion step, wherein a processing liquid containing a coagulant is ejected from a processing liquid inkjet head and adhered to a recording medium; and an ink adhesion step, wherein an aqueous ink composition containing a coloring material is ejected from an ink inkjet head and adhered to the recording medium. The processing liquid adhesion step and the ink adhesion step are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. Using the same scan, the processing liquid and the ink composition are adhered to the same scanned area. The coagulant is a calcium salt, and the content of the calcium salt relative to the total mass of the processing liquid is 0.35 mol / kg or less. In the processing liquid adhesion step, the maximum value of the amount of calcium salt adhered in the area of ​​the recording medium where the processing liquid and the ink composition are adhered is in the range of 0.6 μmol / inch. 2 The following describes an air supply process for supplying air to the recording medium in the liquid coating process and the ink coating process.

[0040] Research is underway on recording methods that use processing solutions to reduce and fix the ink's fluidity as early as possible, thereby achieving excellent image quality. This is particularly relevant for low-absorbency or non-absorbent recording media, where ink droplets are difficult to absorb, sometimes mixing and causing uneven bleeding.

[0041] Furthermore, in serial or landscape printers using a processing fluid, if the processing fluid is applied to the recording medium first, followed by the ink (processing fluid ejected first), there is a technical problem of slower recording speed. Additionally, the above method can be achieved in a serial printer by arranging an inkjet head that ejects the processing fluid upstream of the direction intersecting the main scanning direction (main scanning direction) of the printhead and an inkjet head that ejects the ink downstream. However, in this case, the overall length of the printhead in the sub-scanning direction increases, resulting in a larger device.

[0042] Therefore, from the perspective of improving recording speed and miniaturizing the device, a recording method was studied in which the inkjet head that ejects ink and the inkjet head that ejects processing liquid are arranged laterally in the scanning direction, so that the ink and processing liquid are ejected simultaneously in the same scanning area.

[0043] However, simultaneous ejection of the processing liquid tends to result in poorer image quality compared to ejecting the processing liquid first. This is presumably because ink droplets on the recording medium cannot come into contact with the processing liquid droplets and therefore do not undergo a coagulation reaction. As mentioned above, the deterioration in image quality is due to the aggregation and mixing of ink droplets, leading to image quality disorder. This is also known as bleed unevenness. To obtain excellent image quality, it is necessary to suppress bleed unevenness.

[0044] Therefore, by using highly reactive polyvalent metal salts, particularly calcium salts, as coagulants in the processing solution, excellent image quality can be achieved (by suppressing uneven bleeding). This is presumably because these salts effectively prevent ink droplets from contacting the processing solution on the recording medium from flowing freely. However, when using polyvalent metal salts as coagulants, depending on their concentration, they sometimes crystallize near the surface of the recorded material, resulting in whitening, which appears as white spots on the printed surface.

[0045] On the other hand, simultaneous jetting presents a technical problem of poor nozzle clogging recovery. During the main scan of the inkjet head, the mist of the processing liquid easily flies into the nozzles that eject ink. If the ink reacts with the mist of the processing liquid in the nozzle and becomes foreign matter, the clogging is difficult to recover even after cleaning. In addition, the clogging recovery is significantly worsened when calcium salts are used as coagulants.

[0046] Therefore, excellent clogging recovery can be obtained when the concentration of calcium salts in the processing solution is below a specified level. This is presumably because a lower concentration of calcium salts in the processing solution suppresses reactivity and reduces the amount of foreign matter generated by the reaction between ink and processing solution in the nozzle. However, in this case, due to the low reactivity of the processing solution, the image quality of the recorded image deteriorates (due to suppression of uneven bleeding).

[0047] In this way, it is very difficult to achieve excellent nozzle clogging recovery, image quality (suppressing uneven bleeding), and whitening reduction of printed materials when spraying simultaneously, which was previously very difficult.

[0048] Recent findings indicate that in the ink adhesion process, an air-blowing step that promotes drying by supplying air to the ink-adhered area of ​​the recording medium can significantly improve nozzle clogging recovery, image quality (suppressing uneven bleeding), and reduction of whitening in printed materials during simultaneous ink ejection. This air-blowing step promotes the evaporation of water contained in the ink or processing liquid adhering to the recording medium, increasing the concentration of calcium ions. It is speculated that calcium ions tend to exhibit particularly increased reactivity with increasing concentration, thus achieving excellent image quality (reduced uneven bleeding) even with accelerated water evaporation via the air-blowing step. Furthermore, since the coagulant concentration of the processing liquid is low before accelerated evaporation on the recording medium, it also reduces the likelihood of ink reacting with the processing liquid in the nozzle and becoming foreign matter, further enhancing clogging recovery.

[0049] The following describes each step of the recording method described in this embodiment.

[0050] 1.1 Processing liquid adhesion procedure

[0051] The recording method according to this embodiment includes a processing liquid adhesion step of ejecting a processing liquid containing a coagulant from a processing liquid inkjet head and attaching it to a recording medium.

[0052] 1.1.1 Attachment method

[0053] The recording method described in this embodiment performs a processing liquid adhesion step and an ink adhesion step (described later) by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. The processing liquid and the ink composition (described later) are adhered to the same scanning area using the same scan. In the processing liquid adhesion step, the maximum value of the calcium salt adhesion amount in the area where the processing liquid and ink composition of the recording medium are adhered is within the range of 0.6 μmol / inch. 2 the following.

[0054] In the case where the above-described attachment method involves a nozzle array on the nozzle surface of both a liquid inkjet printhead and an ink printhead, which consists of multiple nozzles arranged in a direction intersecting the direction in which the printhead moves (hereinafter also referred to as the "nozzle array direction"), when the nozzle array of the liquid inkjet printhead is projected along the head movement direction, it can be configured in a manner that at least partially overlaps with the nozzle array of the ink inkjet printhead in the nozzle array direction (forward ejection), and preferably in a manner that completely overlaps (completely simultaneous ejection). Examples of such printhead configurations will be described later.

[0055] In the processing liquid adhesion process, the maximum range of calcium salt adhesion in the area where the processing liquid of the recording medium and the ink composition adhere is 0.6 μmol / inch. 2 The preferred value is 0.5 μmol / inch. 2 The following is more preferably 0.4 μmol / inch. 2 The following is further preferred: 0.3 μmol / inch 2 The following is particularly preferred: 0.2 μmol / inch 2 The following is a lower limit; no particular limitation is specified, but 0.05 μmol / inch is preferred. 2 The above, more preferably 0.1 μmol / inch 2 above.

[0056] On the other hand, the maximum range of calcium salt adhesion is 0.6 μmol / inch. 2 The preferred value is 0.55 μmol / inch. 2 The following is more preferably 0.50 μmol / inch. 2The lower limit is not specifically limited, but is preferably 0.1 μmol / inch. 2 The above, more preferably 0.2 μmol / inch 2 The above is further preferably 0.3 μmol / inch. 2 The above, particularly preferred, is 0.4 μmol / inch. 2 above.

[0057] If the maximum range of calcium salt adhesion is 0.6 μmol / inch 2 The following methods can effectively reduce whitening of printed materials and also provide good abrasion resistance. The maximum range of calcium salt adhesion is particularly high, around 0.05 μmol / inch. 2 The above conditions tend to result in excellent image quality (even with uneven ink bleeding). It should be noted that the above-mentioned adhesion range represents the maximum adhesion amount; areas on the recording medium may also have adhesion amounts smaller than this maximum. On the recording medium, the amount of calcium salts adhering to lighter areas of the image can be reduced based on the ink adhesion amount, or the adhesion amount can be kept constant.

[0058] It should be noted that the amount of calcium salt adhering [μmol / inch] 2 The amount of treatment liquid adhering to the surface [mg / inch] can be determined. 2 The product of the calcium salt concentration [mol / kg] and the calcium salt adhesion amount [μmol / inch] is calculated. 2 The preferred amount of calcium ions attached is [μmol / inch]. 2 That is, the preferred molar number of the calcium salt is the number of molars of calcium contained in the calcium salt.

[0059] The preferred amount of treatment fluid adhering to the recording medium is 0.1–5 mg / inch. 2 More preferably 0.1–4 mg / inch 2 More preferably 0.1–3 mg / inch 2 The preferred concentration is 0.3–2.5 mg / inch. 2 More particularly preferred is 0.3–2 mg / inch. 2 .

[0060] On the other hand, the preferred amount of treatment fluid adhering to the recording medium is 1 to 10 mg / inch per unit area. 2 More preferably 1–7 mg / inch 2 More preferably 1–5 mg / inch 2 The preferred concentration is 1.5–4 mg / inch. 2 More preferably, the concentration is 1.5–3.5 mg / inch.2 .

[0061] With a higher concentration of treatment solution adhering to the surface, the number of droplets sprayed per pass also increases, making mist formation more likely and resulting in slightly poorer clogging recovery. Furthermore, it has recently been found that the amount of calcium salt adhering to the surface [μmol / inch] has a particularly significant impact on clogging recovery. 2 Instead of the amount of treatment fluid adhering [mg / inch] 2 If the amount of treatment liquid adhering to the surface is within the range described above, it tends to have better nozzle clogging recovery, image quality (uneven bleeding), and whitening reduction properties of the printed material. It should be noted that it is also preferable to set the maximum amount of treatment liquid adhering to the range described above.

[0062] The maximum weight range of each droplet of the treatment solution is preferably 0.1 to 30 ng. More preferably, it is 0.5 to 5 ng, more preferably 1 to 5 ng, even more preferably 2 to 4 ng, and particularly preferably 2.5 to 3.5 ng.

[0063] On the other hand, the maximum weight range of each droplet of the treatment liquid is preferably 5 to 30 ng, more preferably 5 to 25 ng, even more preferably 7 to 20 ng, and particularly preferably 9 to 15 ng.

[0064] This increases the contact opportunities between the processing liquid and the ink on the recording medium, resulting in better image quality (uneven bleeding) and a tendency to achieve better nozzle clogging recovery.

[0065] 1.1.2 Recording Media

[0066] In the recording method according to this embodiment, the surface temperature of the recording medium to which the coating is applied is preferably 45°C or lower in the processing liquid coating step and the ink coating step described later. More preferably, it is 40°C or lower, more preferably 35°C or lower, more preferably 30°C or lower, and even more preferably 25°C or lower. Furthermore, room temperature without heating is particularly preferred.

[0067] The lower limit of the aforementioned surface temperature is not particularly limited, but it is preferably 10°C or higher, more preferably 15°C or higher. Further preferably, it is 20°C or higher. More preferably, it is 30°C or higher, more preferably 35°C or higher, and even more preferably 38°C or higher.

[0068] As a method to promote the evaporation of moisture from the ink or reaction solution adhering to the recording medium, methods such as heating the recording medium with hot air or an impression plate heater are also considered. However, with such heating methods, the ink near the nozzle is also accelerated to dry due to the heat, making clogging recovery particularly prone to deterioration. Furthermore, if foreign matter generated near the nozzle solidifies due to heating, clogging recovery is particularly poor. Therefore, temperatures below the aforementioned surface temperature range tend to have better clogging recovery and are thus preferred. On the other hand, temperatures above the aforementioned surface temperature range tend to have better image quality and are therefore preferred.

[0069] The recording medium used to form an image using the recording method according to this embodiment may have a recording surface that absorbs liquids such as ink compositions, or it may not have a recording surface that absorbs liquids. Therefore, there are no particular limitations on the recording medium; examples include liquid-absorbing recording media such as paper and cloth, liquid-low-absorbency recording media such as printing paper, and liquid-non-absorbency recording media such as metals, glass, films, and polymers. However, the superior effect of the recording method according to this embodiment is more significant when recording images using low-absorbency or non-absorbency recording media. That is, according to the recording method according to this embodiment, excellent image quality can be obtained even with low-absorbency or non-absorbency recording media that are more prone to uneven bleeding.

[0070] Recording media with low or no liquid absorption properties refer to recording media that have the property of being completely non-absorbent or almost non-absorbent of liquids. Quantitatively, recording media with low or no liquid absorption properties refer to those used in the Bristol process from the start of contact to 30 msec. 1 / 2 The water absorption rate up to this point is 10 mL / m 2 The following is a description of the recording media. The Bristol method is the most widely used method for determining liquid absorption over a short period of time and is also adopted by the Japan Pulp Technology Association (JAPAN TAPPI). Details of the test method are described in Standard No. 51 "Paper and Board - Liquid Absorption Test Method - Bristol Method" of the "JAPAN TAPPI Pulp Test Methods 2000 Edition". In contrast, recording media with liquid absorption refers to recording media that are not liquid-absorbent or have low liquid absorption. It should be noted that in this specification, low liquid absorption and non-absorbent liquid absorption are sometimes simply referred to as low absorption and non-absorbent.

[0071] Examples of non-absorbent liquid recording media include films or sheets made of plastics such as polyvinyl chloride, polyethylene, polypropylene, and polyethylene terephthalate (PET); metal plates such as iron, silver, copper, and aluminum; metal plates or plastic films manufactured by vapor deposition of these various metals; and plates made of alloys such as stainless steel or cast iron. Additionally, examples include recording media with plastic coated on a paper substrate, recording media with a plastic film bonded to a paper substrate, and plastic films without an absorbent layer (acceptor layer). Examples of plastics mentioned here include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0072] In addition, as a recording medium with low liquid absorption, examples include recording media with a low-absorption coating layer on the surface. For example, as a recording medium with paper as the substrate, examples include printing paper such as coated paper, coated paper, and cast paper. As a recording medium with plastic film as the substrate, examples include recording media with hydrophilic polymers coated on the surface of polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene, etc., and recording media with particles such as silica and titanium coated together with an adhesive.

[0073] There are no particular limitations on liquid-absorbent recording media. Examples include ordinary paper such as electrophotographic paper with high liquid permeability, and inkjet paper (inkjet-specific paper with an ink-absorbing layer composed of silica or alumina particles, or an ink-absorbing layer composed of hydrophilic polymers such as polyvinyl alcohol (PVA) or polyvinylpyrrolidone (PVP)). Furthermore, cloth and non-woven fabrics can also be examples of liquid-absorbent recording media.

[0074] It should be noted that the recording medium can also be colorless and transparent, translucent, colored and transparent, colored and opaque, or colorless and opaque. Furthermore, the recording medium itself can be colored, translucent, or transparent.

[0075] In the examples described above, the recording medium is more preferably a low-absorbency recording medium or a non-absorbent recording medium. This further allows for the enjoyment of the effects of the present invention. That is, such recording media are particularly prone to uneven bleed-out because the ink composition is more difficult to wet and spread; however, according to the recording method of this embodiment, even with such recording media, excellent reduction of bleed-out unevenness is possible.

[0076] 1.1.3 Treatment fluid

[0077] The following describes the components of the processing liquid used in the processing liquid adhesion process. It should be noted that the processing liquid is not an ink composition used to color the recording medium, but rather an auxiliary liquid used in conjunction with an ink composition used for coloring. Furthermore, the processing liquid may contain coloring materials such as pigments, preferably 0.2% by mass or less, more preferably 0.1% by mass or less, and even more preferably 0.05% by mass or less, with a lower limit of 0% by mass, relative to the total mass of the processing liquid. The processing liquid preferably does not contain coloring materials.

[0078] [Flocculant]

[0079] The processing solution used in the recording method of this embodiment contains a calcium salt coagulant, and the content of calcium salt relative to the total mass of the processing solution is 0.35 mol / kg or less.

[0080] Calcium salts can cause the coloring materials or resin particles contained in the ink to aggregate by reacting with them. This aggregation can, for example, improve the color rendering of the coloring materials, enhance the fixing properties of the resin particles, and / or increase the viscosity of the ink.

[0081] It should be noted that coagulants other than calcium salts have lower reactivity compared to calcium salts, thus failing to achieve adequate image quality. Furthermore, when using cationic polymers as coagulants, the clogging recovery during simultaneous spraying is particularly poor, presumably due to the formation of exceptionally large foreign matter during the reaction with the ink. Additionally, when using coagulants other than calcium salts, even with increased concentration due to water evaporation caused by airflow, reactivity is difficult to improve.

[0082] Calcium salts are compounds composed of calcium ions and anions. The anions that constitute calcium salts can be inorganic or organic ions. Examples of such inorganic ions include chloride ions, bromide ions, iodide ions, nitrate ions, sulfate ions, and hydroxide ions. Examples of such organic ions include organic acid ions, such as carboxylic acid ions and formic acid ions.

[0083] The calcium salt is preferably a calcium salt of an organic acid. Compared with calcium salts composed of inorganic ions, calcium salts of organic acids tend to have better abrasion resistance.

[0084] Specific examples of calcium salts include heavy calcium carbonate and light calcium carbonate, calcium nitrate, calcium chloride, calcium sulfate, calcium hydroxide, calcium formate (molecular weight 130.1), calcium propionate (molecular weight 186.2), calcium acetate, and calcium lactate. These calcium salts can be used alone or in combination with two or more. It should be noted that these calcium salts can also contain hydrated water in their raw material form; for example, calcium nitrate tetrahydrate (molecular weight 236.2), calcium chloride dihydrate (molecular weight 236.2), calcium acetate monohydrate (molecular weight 176.2), and calcium lactate pentahydrate (molecular weight 308.3) are examples.

[0085] The calcium salt content relative to the total mass of the treatment solution is 0.35 mol / kg or less, preferably 0.32 mol / kg or less, more preferably 0.30 mol / kg or less. The lower limit is not particularly limited, but is preferably 0.01 mol / kg or more, more preferably 0.05 mol / kg or more, further preferably 0.10 mol / kg or more, and particularly preferably 0.20 mol / kg or more.

[0086] In addition, the calcium salt content relative to the total mass of the treatment solution is preferably 10.0% by mass or less, more preferably 0.1% to 6% by mass, even more preferably 1.0% to 5% by mass, and particularly preferably 1.5% to 4% by mass.

[0087] [Water-soluble low-molecular-weight organic compounds]

[0088] The processing liquid used in the recording method according to this embodiment may contain a water-soluble low-molecular-weight organic compound. The water-soluble low-molecular-weight organic compound may be an organic solvent whose monomer is liquid at room temperature, or a compound whose monomer is solid at room temperature. An organic solvent is preferred.

[0089] Here, in the context of water-soluble low-molecular-weight organic compounds, "water-soluble" refers to a solubility exceeding 10g in 100g of water at 20°C. The method for determining the solubility of water-soluble low-molecular-weight organic compounds is as follows: First, at 20°C, a specified amount of the compound is mixed in 100g of water and stirred for 30 minutes. After stirring, for compounds that are liquid at room temperature, if no phase separation or island-like structures are formed, they are considered dissolved. Furthermore, for compounds that are solid at room temperature, if no dissolved residue remains, they are considered dissolved.

[0090] Thus, when a specified amount of a compound is mixed in 100g of water, the highest specified amount among the specified amounts that are considered to be dissolved is taken as the solubility. Low-molecular-weight organic compounds with a solubility exceeding 10g are considered water-soluble low-molecular-weight organic compounds.

[0091] It should be noted that water-soluble low-molecular-weight organic compounds can be compounds that are completely mixed with water or compounds that are mixed with water.

[0092] In this specification, "completely mixable with water" means that the organic compound and water are mutually soluble, that is, the solubility of the organic compound in 100g of water at 20°C is infinite. Conversely, "mixable with water" means that the organic compound and water have finite solubility, that is, the solubility of the organic compound in at least 10g of water at 20°C exceeds 10g.

[0093] The solubility of water-soluble low-molecular-weight organic compounds exceeds 10g, but there is no upper limit; it can be infinite. Preferably, the solubility is 11g or more, more preferably 50g or more.

[0094] Furthermore, in water-soluble low-molecular-weight organic compounds, "low-molecular-weight" refers to a molecular weight of 500 or less. The molecular weight is preferably 400 or less, more preferably 300 or less, and even more preferably 50 to 200.

[0095] The water-soluble low-molecular-weight organic compound preferably contains a compound with a standard boiling point of 150–350°C. A standard boiling point of 150–300°C is more preferred. Furthermore, the water-soluble low-molecular-weight organic compound preferably contains a compound with a melting point of 90°C or less. Even more preferably, it contains a compound with a melting point of 80°C or less. Additionally, the melting point is preferably -70°C or higher.

[0096] Examples of water-soluble low-molecular-weight organic compounds include resin-soluble substances, polyols, glycol ethers, and alkanolamines. Resin-soluble substances are preferably selected from amides, sulfur-containing solvents, and cyclic ethers.

[0097] Among them, resin-soluble substances, polyols, and glycol ethers are preferred.

[0098] Further preferred options include any resin-soluble substance from the categories of amides, sulfur-containing solvents, and cyclic ethers with a standard boiling point of 150–300 °C; and any compound from the categories of polyols and glycol ethers with a standard boiling point of 150–250 °C. Other water-soluble low-molecular-weight organic compounds may also be included as needed.

[0099] The water-soluble low-molecular-weight organic compound preferably contains 50% by mass or less relative to the total mass of the treatment liquid. Furthermore, it preferably contains 1% by mass or more relative to the total mass of the treatment liquid. More preferably, it contains 10 to 40% by mass, more preferably 15 to 35% by mass, and particularly preferably 20 to 30% by mass.

[0100] <Resin Dissolved Substances>

[0101] Examples of resin-dissolving substances include amides, sulfur-containing solvents, and cyclic ethers. Preferably, any one of these amides, sulfur-containing solvents, or cyclic ethers has a standard boiling point of 150–300°C. It should be noted that resin-dissolving substances refer to organic compounds that have the function of dissolving resin and improving abrasion resistance, but are not limited to this function.

[0102] Examples of the aforementioned amides include cyclic amides (lactams) such as 2-pyrrolidone (2P), 2-piperidinone, ε-caprolactam (CPL), N-methyl-ε-caprolactam, N-cyclohexyl-2-pyrrolidone, N-methylpyrrolidone, N-ethylpyrrolidone, N-butylpyrrolidone, 5-methyl-2-pyrrolidone, β-propiolactam, and ω-heptyllactam, as well as N,N-dimethylacetoacetamide, N,N-diethylacetoacetamide, N-methylacetoacetamide, and N,N-dimethylacetoacetamide. Isobutyric acid amide, N,N-dimethylformamide, N,N-diethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylpropionamide, 3-methoxy-N,N-dimethylpropionamide (DMPA), 3-n-butoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, 3-methoxy-N,N-methylethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-diethylpropionamide, etc., are all chain amides. Among them, any one of 2-pyrrolidone (2P), ε-caprolactam (CPL), and 3-methoxy-N,N-dimethylpropionamide (DMPA) is more preferred, as they tend to improve the storage stability of the treatment solution.

[0103] Examples of sulfur-containing solvents include 3-methylcyclobutane sulfone, sulfolane, ethyl isopropyl sulfone, ethyl methyl sulfone, dimethyl sulfone, dimethyl sulfoxide (DMSO), diethyl sulfoxide, tetramethylene sulfoxide, and methyl phenyl sulfoxide. Among these, dimethyl sulfoxide (DMSO) is more preferred, as it tends to improve the storage stability of the treated solution.

[0104] Examples of the aforementioned cyclic ethers include isosorbide dimethyl ether, 3-methyl-3-oxetane methanol, 3-ethyl-3-oxetane methanol (DMHD), 2-hydroxymethyloxetane, tetrahydrofurfuryl alcohol, sorbitol, glyceryl formaldehyde, 1,4-dioxane-2,3-diol, and dihydro-L-glucanone. Among these, 3-ethyl-3-oxetane methanol (DMHD) is more preferred, as it tends to provide superior storage stability of the treated solution.

[0105] <Polyols and glycol ethers>

[0106] Other than the resin dissolving substances mentioned above, water-soluble low-molecular-weight organic compounds can include, for example, polyols and glycol ethers. Among them, any one of the polyols or glycol ethers with a standard boiling point of 150 to 250°C is preferred.

[0107] (Polyols)

[0108] Polyols are preferably diols, or compounds formed by the intermolecular condensation of diols between hydroxyl groups. In this case, it is a compound having two hydroxyl groups.

[0109] Additionally, as polyols, examples include diols or compounds formed by the intermolecular condensation of diols between hydroxyl groups, where the hydrogen atoms are replaced by hydroxyl groups. In this case, the compound has three or more hydroxyl groups.

[0110] The diol unit in a polyol, or a compound formed by the intermolecular condensation of diols between hydroxyl groups, preferably has 2 to 10 carbon atoms, more preferably 3 to 8. Furthermore, the polyol molecule preferably has 2 to 15 carbon atoms, more preferably 3 to 10. The standard boiling point of the polyol is preferably 150 to 250°C.

[0111] Examples of polyols with standard boiling points of 150–250°C include ethylene glycol (standard boiling point 198°C, miscible with water), diethylene glycol (standard boiling point 244°C, completely miscible with water), 1,2-propanediol (propylene glycol: PG) (standard boiling point 188°C, completely miscible with water), dipropylene glycol (standard boiling point 227°C, completely miscible with water), 1,2-butanediol (standard boiling point 193°C, miscible with water), 1,2-pentanediol (standard boiling point 210°C, miscible with water), 1,2-hexanediol (1,2HD) (standard boiling point 223°C, completely miscible with water), 1,3-propanediol (standard boiling point 214°C, completely miscible with water), 1,4-butanediol (standard boiling point 228°C, completely miscible with water), and 2,3-butanediol (standard boiling point 177°C, miscible with water). 1,3-Butanediol (standard boiling point 207℃, completely miscible with water), 3-methyl-1,3-butanediol (standard boiling point 203℃, completely miscible with water), 2-methyl-1,3-propanediol (standard boiling point 214℃, completely miscible with water), 2,2-dimethyl-1,3-propanediol (standard boiling point 208℃, solubility 83 g / 100 g water) and 2-methylpentane-2,4- Polyols such as 2,5-dimethyl-2,5-hexanediol (standard boiling point 197°C, completely miscible with water), 2,5-dimethyl-2,5-hexanediol (standard boiling point 218°C, solubility 14 g / 100 g water), 1,5-pentanediol (standard boiling point 242°C, miscible with water), 3-methyl-1,5-pentanediol (standard boiling point 250°C, completely miscible with water), and 1,6-hexanediol (standard boiling point 250°C, miscible with water) are preferred. Polyols with 10 or fewer carbon atoms are more preferred as polyols.

[0112] Among polyols, alkanediols with a standard boiling point of 150–250 °C and fewer than 10 carbon atoms are more preferred, and alkanediols with a standard boiling point of 150–250 °C and fewer than 6 carbon atoms are even more preferred. Examples of alkanediols include ethylene glycol, propylene glycol, 1,2-propanediol, 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,3-propanediol, and 1,3-butanediol, among others, which are 1,2-alkanediols.

[0113] (Diol ethers)

[0114] Diol ethers are compounds formed by the etherification of one or more hydroxyl groups of a diol. Here, diols also include diols formed by the condensation of two or more molecules of a diol between intermolecular hydroxyl groups.

[0115] As the aforementioned glycol ethers, mono- or di-ethers of alkylene glycols are preferred. As the ethers formed by the etherification process, alkyl ethers are preferred. The alkylene group of the alkylene glycol constituting the glycol ether and the alkyl group of the alkyl ether preferably have 1 to 5 carbon atoms, more preferably 2 to 4. Glycol ethers with a standard boiling point of 150 to 250°C are preferred.

[0116] Examples of glycol ethers include ethylene glycol monomethyl ether (completely miscible with water), ethylene glycol monoethyl ether (miscible with water), ethylene glycol monoisopropyl ether (solubility 100 g / 100 g water), ethylene glycol monopropyl ether (miscible with water), ethylene glycol monoisobutyl ether (solubility 75.5 g / 100 g water), ethylene glycol mono-tert-butyl ether (miscible with water), and ethylene glycol monobutyl ether (solubility 100 g / 100 g water). Dialkylene glycol dialkyl ethers (glycol dimethyl ether), including diethylene glycol monomethyl ether (completely mixable with water), diethylene glycol monoethyl ether (completely mixable with water), diethylene glycol monoisopropyl ether (completely mixable with water), diethylene glycol monoisobutyl ether (completely mixable with water), diethylene glycol monobutyl ether (completely mixable with water), triethylene glycol monomethyl ether (completely mixable with water), triethylene glycol monoethyl ether (completely mixable with water), and triethylene glycol diol monobutyl ether (completely mixable with water), are alkylene glycol dialkyl ethers.

[0117] Furthermore, regarding the aforementioned glycol ethers, compared to monoethers, diethers tend to more readily dissolve or swell the resin in the ink, and thus tend to improve the abrasion resistance of the formed image; therefore, they are more preferred. On the other hand, from the viewpoint of excellent preservation stability of the processing solution, monoethers are preferred.

[0118] In the recording method according to this embodiment, the processing liquid preferably contains at least 40% by mass, more preferably at least 30% by mass, of any one of polyols or glycol ethers as a water-soluble low-molecular-weight organic compound relative to the total mass of the processing liquid. Furthermore, as a lower limit, it contains at least 0% by mass, preferably at least 10% by mass, and more preferably at least 15% by mass, relative to the total mass of the ink composition.

[0119] Furthermore, it is more preferable to set the above content range to include any one of polyols and glycol ethers with a standard boiling point of 150 to 250°C, and even more preferably to include alkanediols with a standard boiling point of 150 to 250°C and fewer than 10 carbon atoms, and particularly preferably to include alkanediols with a standard boiling point of 150 to 250°C and fewer than 6 carbon atoms.

[0120] <Other Compounds>

[0121] The processing liquid used in the recording method described in this embodiment may, as needed, contain other water-soluble low-molecular-weight organic compounds.

[0122] (Alkanolamines)

[0123] The treatment solution may contain alkanolamines as water-soluble low-molecular-weight organic compounds. Alkanolamines refer to compounds having hydroxyl and amino groups on an alkane skeleton. The alkanolamine molecule has 1 or more hydroxyl groups, preferably 1 to 5, more preferably 2 to 3. The alkanolamine molecule preferably has 1 to 20 carbon atoms, more preferably 2 to 10, and even more preferably 6 to 9. Each alkane skeleton preferably has 1 to 6 carbon atoms, more preferably 2 to 4. The alkanolamine molecule has 1 or more amino groups, preferably 1 to 5, more preferably 1 to 2.

[0124] As an alkanolamine, there are no particular limitations. Examples include ethanolamine (mixable with water), N-methylethanolamine (solubility 100g / 100g water), N,N-dimethylethanolamine (completely mixable with water), N-ethylethanolamine (mixable with water), N-butylethanolamine (mixable with water), N,N-diethylethanolamine (mixable with water), diethanolamine (solubility 100g / 100g water), N-methyldiethanolamine (solubility 100g / 100g water), N-ethyldiethanolamine (mixable with water), N-butyldiethanolamine (mixable with water), N-tert-butyldiethanolamine (completely mixable with water), triethanolamine (completely mixable with water), isopropanolamine (mixable with water), N,N-dimethylisopropanolamine (completely mixable with water), N,N The following are listed: diethylisopropanolamine (mixable with water), diisopropanolamine (solubility 87 g / 100 g water), triisopropanolamine (solubility 83 g / 100 g water), diethanolisopropanolamine (mixable with water), ethanol diisopropanolamine (mixable with water), N,N-dimethylpropanolamine (mixable with water), 2-amino-1-propanol (completely mixable with water), 2-amino-2-methyl-1-propanol (completely mixable with water), 5-amino-1-pentanol (mixable with water), 2-amino-2-methyl-1,3-propanediol (mixable with water), 2-amino-2-hydroxymethyl-1,3-propanediol (mixable with water), 3-amino-1,2-propanediol (mixable with water), 3-methylamino-1,2-propanediol (completely mixable with water), tripropanolamine, and tributanolamine. Triethanolamine and triisopropanolamine are preferred, and triisopropanolamine is more preferred. Alkylamines can be used alone or in combination with two or more.

[0125] When alkanolamines are present, their content relative to the total mass of the treatment solution is preferably 1% by mass or less, more preferably 0.05 to 0.5% by mass.

[0126] (Polyols with a standard boiling point exceeding 280°C)

[0127] The treatment solution preferably does not contain more than 3% by mass of water-soluble low-molecular-weight organic compounds with a standard boiling point exceeding 280°C. More preferably, it does not contain more than 1% by mass, and even more preferably, it does not contain more than 0.5% by mass. Even more preferably, it does not contain more than 0.1% by mass.

[0128] In this case, the processing solution may or may not contain polyols with a standard boiling point exceeding 280°C, and even if it does contain them, the content should be below the aforementioned level. If the content of polyols with a standard boiling point exceeding 280°C is within the aforementioned range, a significant decrease in the drying properties of the processing solution can be prevented. As a result, even when recording on low-absorbency or non-absorbent recording media, there is a tendency to prevent a decrease in image fixing properties. Furthermore, even if the temperature of the recording medium during heat drying is relatively low, there is a tendency to achieve sufficient drying. Examples of such polyols with a standard boiling point exceeding 280°C include glycerol (standard boiling point of 290°C), and alkylolamines such as triisopropanolamine are not included.

[0129] 〔water〕

[0130] The processing liquid used in the recording method according to this embodiment may contain water, and is preferably an aqueous processing liquid. A composition that contains at least water as the main solvent component (liquid medium component) of the composition is called an aqueous composition.

[0131] Examples of water types include pure water such as ion-exchanged water, ultrafiltration water, reverse osmosis water, and distilled water, as well as ultrapure water, which reduces ionic impurities. Furthermore, if water that has been sterilized through ultraviolet irradiation or the addition of hydrogen peroxide is used, the growth of bacteria or fungi can be inhibited during long-term storage of the treated solution.

[0132] The water content in the liquid medium is preferably 30% by mass or more, more preferably 30-99% by mass. Further, it is preferably 30-95% by mass, more preferably 40-90% by mass, and even more preferably 50-80% by mass. It should be noted that the liquid medium refers to solvent components such as water or organic solvents.

[0133] Furthermore, the water content relative to the total mass of the treatment liquid is preferably 30% by mass or more, more preferably 40% by mass or more, more preferably 45% by mass or more, and particularly preferably 50% by mass or more. There is no particular upper limit to the water content; for example, relative to the total mass of the treatment liquid, it is preferably 99% by mass or less, more preferably 90% by mass or less, and more preferably 80% by mass or less.

[0134] [surfactants]

[0135] The processing liquid used in the recording method according to this embodiment may also contain a surfactant. The surfactant has the function of adjusting the surface tension of the processing liquid, such as adjusting its wettability with the recording medium. Among the surfactants, acetylene glycol-based surfactants, silicone-based surfactants, and fluorinated surfactants are preferred, with silicone-based surfactants being more preferred.

[0136] As an acetylene glycol surfactant, there are no particular limitations. Examples 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 are trade names). Products & Chemicals, OLFINEB, Y, P, A, STG, SPC, E1004, E1010, PD-001, PD-002W, PD-003, PD-004, EXP.4001, EXP.4036, EXP.4051, AF-103, AF-104, AK-02, SK-14, AE-3 (all trade names, manufactured by Nissin Chemical Industry Co., Ltd.), ACETYLENOLE 00, E00P, E40, E100 (all trade names, manufactured by Kawaken Fine Chemicals Co., Ltd.).

[0137] There are no particular limitations on the silicone-based surfactants, but polysiloxane compounds are preferred. There are no particular limitations on the polysiloxane compounds used; for example, polyether-modified organosiloxanes can be listed. Commercially available products of this polyether-modified organosiloxane include, for example, BYK-306, BYK-307, BYK-333, BYK-341, BYK-345, BYK-346, BYK-348 (trade names, manufactured by BYK-Chemie Japan), 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, KF-6017 (trade names, manufactured by Shin-Etsu Chemical Industry Co., Ltd.), SILFACE. SAG002, 005, 503A, 008 (the above are trade names, manufactured by Nisshin Chemical Industry Co., Ltd.), etc.

[0138] As a fluorinated surfactant, fluorinated modified polymers are preferred. Specific examples include BYK-3440 (manufactured by BYK-Chemie Japan), SURFLON S-241, S-242, and S-243 (trade names, manufactured by AGC Seimei Chemical Co., Ltd.), and FTERGENT 215M (manufactured by NEOS).

[0139] When the treatment solution contains surfactants, it may contain multiple surfactants. The content of surfactants in the treatment solution relative to the total mass of the treatment solution can be 0.1% by mass or more and 2% by mass or less, preferably 0.2% by mass or more and 1.5% by mass or less, more preferably 0.3% by mass or more and 1.0% by mass or less.

[0140] [Other ingredients]

[0141] The processing liquid used in the recording method described in this embodiment may contain additives, resin dispersants, preservatives / mildew inhibitors, rust inhibitors, chelating agents, viscosity modifiers, antioxidants, etc., in addition to the components mentioned above, as long as it does not impair the function.

[0142] Examples of additives include ureas, amines, and sugars.

[0143] Examples of urea derivatives include urea, ethylidene urea, tetramethylurea, thiourea, 1,3-dimethyl-2-imidazolinone, and betaine derivatives (trimethylglycine, triethylglycine, tripropylglycine, triisopropylglycine, N,N,N-trimethylalanine, N,N,N-triethylalanine, N,N,N-triisopropylalanine, N,N,N-trimethylmethylalanine, carnitine, acetylcarnitine, etc.).

[0144] Examples of amines include diethanolamine, triethanolamine, and triisopropanolamine. Ureas and amines can also function as pH adjusters.

[0145] As sugars, examples include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, aldonic acid, glucosyl alcohol (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, and maltotriose.

[0146] 1.2 Ink Adhesion Process

[0147] An ink adhesion process is provided, in which a water-based ink composition containing coloring material is ejected from an inkjet head and adhered to a recording medium.

[0148] 1.2.1 Attachment method

[0149] The recording method according to this embodiment performs the aforementioned processing liquid adhesion process and ink adhesion process by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. The processing liquid and ink composition are adhered to the same scanned area using the same scan. This adhesion method can be achieved using the inkjet head configuration described above or later.

[0150] Thus, by using the same scan, the processing liquid and ink composition overlap and adhere in the same scan area.

[0151] The preferred adhesion amount of the ink composition is 0.5–40 mg / inch per unit area of ​​the recording medium. 2 .

[0152] Furthermore, a concentration of 0.5–20 mg / inch is preferred. 2 More preferably 1–17 mg / inch 2 More preferably 2–15 mg / inch 2 The preferred concentration is 3–12 mg / inch. 2 More preferably 4–10 mg / inch 2 .

[0153] On the other hand, the preferred adhesion amount of the ink composition is 1 to 40 mg / inch per unit area of ​​the recording medium. 2 More preferably 2–34 mg / inch 2 More preferably 4–30 mg / inch 2 The preferred concentration is 6–24 mg / inch. 2 More preferably 8-20 mg / inch 2 .

[0154] The amount of ink composition adhered to can be the range of the maximum amount of ink composition adhered to per unit area of ​​the recording medium.

[0155] In the recording method of this embodiment, the number of scans in which the ink composition adheres to the same scanning area is preferably 10 times or less, more preferably 8 times or less. The lower limit is preferably 2 times or more, more preferably 4 times or more, and even more preferably 6 times or more.

[0156] On the other hand, the number of scans to adhere the ink composition to the same scanning area is preferably 10 times or less, more preferably 5 times or less, even more preferably 3 times or less, particularly preferably 2 times or less. It is even more preferably 1 time or less. It should be noted that the number of scans is more than 1 time.

[0157] Fewer scans result in faster recording speeds, which is preferable. However, as the number of droplets processed per scan increases, clogging recovery tends to deteriorate. Furthermore, the increased number of ink droplets per scan leads to ink leakage and deterioration of image quality. Additionally, ink droplet aggregation can worsen the filling of the ink on the recording medium. Within the range of scan counts, there is a tendency to achieve good recording speed while maintaining excellent clogging recovery and image quality (uneven leakage).

[0158] It should be noted that the number of scans mentioned above, even when using multiple ink compositions, refers to the number of scans performed on a single ink composition. Furthermore, in the case of completely simultaneous spraying, the number of scans in which the ink composition adheres to the same scanning area is the same as the number of scans in which the processing liquid adheres to the same scanning area.

[0159] When recording any area, the number of times the inkjet head passes through that area is also called a "pass". For example, when performing a main scan to adhere ink to the same area four times, that number of passes is called 4 passes, etc.

[0160] For example, in Figure 3 In this case, when the length of one sub-scan in the sub-scanning direction (SS direction) is one-quarter of the length of the nozzle array in the sub-scanning direction (SS direction), four scans are performed on a rectangular scanning area that is one sub-scan length in the sub-scanning direction (SS direction) and extends in the main scanning direction (MS direction). This is the number of scans during observation.

[0161] When main scans and sub-scans are performed alternately, the scan area is a rectangular region that has the length of one sub-scan in the sub-scan direction and extends in the main scan direction.

[0162] Or, for example, in Figure 3 In this case, without performing a sub-scan, it is possible to perform four main scans on the same area of ​​the stopped recording medium to allow ink to adhere, thus achieving a total of four scans. Then, a sub-scan can be performed after the four main scans.

[0163] When a recording medium with a fixed position is subjected to one or more main scans without sub-scanning, the scanning area is a rectangular area that is the length of the inkjet head in the sub-scanning direction and extends in the main scan direction.

[0164] The number of scans is also called the number of scans or passes.

[0165] 1.2.2 Ink Composition

[0166] The following describes the components contained in the ink composition used in the ink application process. The ink composition is an aqueous composition containing coloring materials.

[0167] In addition to coagulants that do not contain calcium salts or other calcium salts, and those that contain coloring materials as an essential component, the composition can also be the same as that of the treatment solution.

[0168] [Coloring materials]

[0169] The ink composition used in the recording method according to this embodiment contains a coloring material. Examples of coloring agents include pigments and dyes.

[0170] (pigment)

[0171] As pigments, for example, carbon black, inorganic pigments containing titanium dioxide, and organic pigments can be used.

[0172] As an inorganic pigment, it can use carbon black (CI Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black, as well as iron oxide, titanium oxide, zinc oxide, and silicon dioxide.

[0173] Examples of carbon blacks include No. 2300, 900, MCF88, No. 20B, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, and No. 2200B manufactured by Mitsubishi Chemical Corporation. Examples of carbon blacks include Color Black FW1, FW2, FW2V, FW18, FW200, S150, S160, S170, Pretex35, U, V, 140U, SpecialBlack6, 5, 4A, 4, and 250 manufactured by Degussa. Examples of carbon blacks include Conductex SC, Raben 1255, 5750, 5250, 5000, 3500, 1255, and 700 manufactured by Columbia Carbon. Examples include Cabot's Regal 400R, 330R, 660R, MogulL, Monarch 700, 800, 880, 900, 1000, 1100, 1300, 1400, and Elftex 12.

[0174] Examples of organic pigments include quinacridone pigments, quinacridone quinone pigments, dioxazine pigments, phthalocyanine pigments, anthraquinone pigments, anthraquinone pigments, indanone pigments, flavanone pigments, perylene pigments, diketopyrrolopyrrole pigments, violet ketone pigments, quinacridone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, isoindolinone pigments, azomethyl alkaloid pigments, or azo pigments.

[0175] The following pigments can be listed as specific examples of organic pigments used in ink compositions.

[0176] Examples of cyan pigments include CI Pigment Blue 1, 2, 3, 15:3, 15:4, 15:34, 16, 22, 60, etc.; CI Vat Blue 4, 60, etc.; preferably, examples include one or more mixtures selected from the group consisting of CI Pigment Blue 15:3, 15:4 and 60.

[0177] Examples of magenta pigments include CI Pigment Red 5, 7, 12, 48(Ca), 48(Mn), 57(Ca), 57:1, 112, 122, 123, 168, 184, 202, and CI Pigment Violet 19. Preferably, examples include one or more mixtures selected from the group consisting of CI Pigment Red 122, 202, 209, and CI Pigment Violet 19. Solid solutions of the above pigments may also be used.

[0178] Examples of yellow pigments include CI pigment yellow, 1, 2, 3, 12, 13, 14C, 16, 17, 73, 74, 75, 83, 93, 95, 97, 98, 119, 110, 114, 128, 129, 138, 150, 151, 154, 155, 180, 185, etc., and preferably, one or more mixtures selected from the group consisting of CI pigment yellow 74, 109, 110, 128, 138, 155 and 180 can be used as examples.

[0179] Examples of orange pigments include CI pigments Orange 36 or 43, or mixtures thereof. Examples of green pigments include CI pigments Green 7 or 36, or mixtures thereof.

[0180] Alternatively, glossy pigments can be used, as long as they exhibit a glossy appearance when adhered to a medium; there are no particular limitations. Examples include metallic particles selected from one or more alloys (also called metallic pigments) of aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, and copper, and pearlescent pigments with a pearlescent luster. Representative examples of pearlescent pigments include titanium dioxide coated with mica, fish scale foil, and bismuth oxychloride, which possess a pearly or interference luster. Furthermore, glossy pigments can also be used to perform surface treatments to inhibit reactions with water.

[0181] Alternatively, white pigments can be used, such as metal oxides, barium sulfate, calcium carbonate, and other metal compounds. Examples of metal oxides include titanium dioxide, zinc oxide, silicon dioxide, aluminum oxide, and magnesium oxide. Furthermore, white pigments can also be made from particles with a hollow structure.

[0182] The aforementioned pigments can be used alone or in combination with two or more. From the viewpoint of preservation stability, such as lightfastness, weather resistance, and gas resistance, organic pigments are preferred.

[0183] Regarding the volume average particle size (D50) of the pigment, the volume average particle size (D50) measured by dynamic light scattering method is 20 nm or more and 300 nm or less, more preferably 30 nm or more and 200 nm or less, and even more preferably 40 nm or more and 100 nm or less.

[0184] Volume average particle size can be measured, for example, using the Nanotrac series particle distribution measuring device manufactured by Microtrac Bell. Furthermore, methods for adjusting the volume average particle size include, for example, adjusting the degree of pigment grinding before dispersion, adjusting the stirring conditions during dispersion (e.g., stirring speed, stirring temperature), and adjusting by using a filter after dispersion.

[0185] Pigments can be dispersed using pigment dispersants. Alternatively, pigments can be dispersed as self-dispersing pigments by oxidizing or sulfonating their surfaces with ozone, hypochlorous acid, fuming sulfuric acid, etc.

[0186] Pigment dispersants function to disperse pigments in ink compositions. Pigment dispersants can be water-soluble, but preferably not completely water-soluble. They are thought to disperse pigments by partially or completely binding to or adsorbing onto the pigment, thereby increasing the hydrophilicity of the pigment surface. Pigment dispersants are preferably polymeric compounds, more preferably resins. It should be noted that pigments dispersed by pigment dispersants that are resins are also specifically referred to as resin-dispersed pigments.

[0187] Resins used as pigment dispersants include, for example, poly(meth)acrylic acid, (meth)acrylic acid-acrylonitrile copolymer, (meth)acrylic acid-(meth)acrylate copolymer, vinyl acetate-(meth)acrylate copolymer, vinyl acetate-(meth)acrylic acid copolymer, vinylnaphthalene-(meth)acrylic acid copolymer, styrene-(meth)acrylic acid copolymer, styrene-(meth)acrylic acid-(meth)acrylate copolymer, styrene-α-methylstyrene-(meth)acrylic acid copolymer, styrene-α-methylstyrene-(meth)acrylic acid-(meth)acrylate copolymer, and other acrylic resins and their salts. It should be noted that, in this specification, polymers having a backbone derived from (meth)acrylic acid but not from maleic acid or similar compounds are referred to as acrylic resins. It should also be noted that, in this specification, "(meth)acrylic acid" refers to acrylic acid or methacrylic acid.

[0188] In addition, resins used as pigment dispersants include maleic acid resins and their salts such as styrene-maleic acid copolymers, styrene-maleic anhydride copolymers, vinyl naphthalene-maleic acid copolymers, and vinyl acetate-maleic ester copolymers; urethane resins and their salts, regardless of whether they have cross-linked structures; polyvinyl alcohols; and vinyl acetate-crotonic acid copolymers and their salts.

[0189] It should be noted that acrylic resins, in addition to polymers of acrylic monomers as described above, can also be copolymers of acrylic monomers with other monomers. For example, vinyl acrylate resins, which are copolymers of other monomers with vinyl monomers, are also called acrylic resins. Furthermore, for example, in the styrene resins described above, resins that are copolymers of styrene monomers and acrylic monomers are also included in the category of acrylic resins. Moreover, when referred to as acrylic resins, their salts or esters are also included.

[0190] Commercially available pigment dispersants include, for example, X-200, X-1, X-205, X-220, X-228 (manufactured by Starlight PMC), Nopcos Perth (registered trademark) 6100, 6110 (manufactured by SAN NOPCO), Joncryl 67, 586, 611, 678, 680, 682, 819 (manufactured by BASF), DISPERBYK-190 (manufactured by BYK-Chemie JAPAN Co., Ltd.), N-EA137, N-EA157, N-EA167, N-EA177, N-EA197D, N-EA207D, E-EN10 (manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.), etc.

[0191] Commercially available acrylic pigment dispersants include BYK-187, BYK-190, BYK-191, BYK-194N, BYK-199 (manufactured by BYK-Chemie Co., Ltd.), AronA-210, A6114, AS-1100, AS-1800, A-30SL, A-7250, and CL-2 (manufactured by Toa Synthetic Co., Ltd.).

[0192] Commercially available carbamate pigment dispersants include BYK-182, BYK-183, BYK-184, BYK-185 (manufactured by BYKChemie Co., Ltd.), TEGO Disperse 710 (manufactured by Evonic Tego Chemi Co., Ltd.), and Borchi (registered trademark) Gen1350 (manufactured by OMG Borschers Co., Ltd.).

[0193] Pigment dispersants can be used alone or in combination with two or more. The total content of pigment dispersants relative to 100% by mass of the ink is 0.1% by mass or more and 30% by mass or less, preferably 5% by mass or more and 25% by mass or less, more preferably 10% by mass or more and 20% by mass or less. By ensuring that the content of pigment dispersants is 0.1% by mass or more, the dispersion stability of the pigment can be ensured. In addition, if the content of pigment dispersants is 30% by mass or less, the viscosity of the ink composition can be kept relatively low.

[0194] Furthermore, the weight-average molecular weight of the pigment dispersant is preferably 500 or higher. Using such a pigment dispersant reduces odor and improves the dispersion stability of the pigment.

[0195] When pigments are dispersed by a pigment dispersant, the ratio of pigment to pigment dispersant is preferably 10:1 to 1:10, more preferably 4:1 to 1:3.

[0196] Self-dispersible pigments are pigments whose surfaces are modified by directly or indirectly binding one or more functional groups selected from the group consisting of carbonyl, carboxyl, acetaldehyde, hydroxyl, sulfone, ammonium, and their salts.

[0197] Examples of self-dispersing pigments include organic pigments such as carbon black, azo lakes, insoluble azo pigments, condensed azo pigments, chelated azo pigments, phthalocyanine pigments, perylene pigments, violet ketone pigments, quinacridone pigments, thioindolinone pigments, quinoline ketone pigments, dioxazine pigments, anthraquinone pigments, nitro pigments, nitroso pigments, and aniline black; and inorganic pigments such as titanium dioxide, zinc oxide, lead white, carbon black, iron oxide red, cinnabar, cadmium red, chrome yellow, ultramarine, cobalt blue, cobalt violet, and zinc chromate.

[0198] From the perspective of being able to print black with high concentration and having better spraying reliability, carbon black is preferred as a self-dispersing pigment.

[0199] As self-dispersible pigments, formulations prepared by known methods or commercially available products can be used. Examples of commercially available products include "Microjet CW1" and "Microjet CW2" manufactured by Orient Chemical Industries, Ltd., and "CAB-O-JET 200" and "CAB-O-JET 300" manufactured by Cabot Corporation.

[0200] (dye)

[0201] Dyes can be used as coloring materials in ink compositions. There are no particular limitations on the type of dye used; acid dyes, direct dyes, reactive dyes, basic dyes, and disperse dyes can all be used.

[0202] The dyes mentioned above can be used alone or in combination with two or more.

[0203] The coloring material is preferably any one of resin-dispersed pigments, self-dispersed pigments, or dyes. Such coloring materials tend to exhibit improved color development and ejection stability because they can disperse well in aqueous inks.

[0204] There is no particular limitation on the lower limit of the content of the coloring material, but it is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, further preferably 1.0% by mass or more, and even more preferably 1.5% by mass or more, relative to the total amount of the ink composition. If the content of the coloring material is within the above range, it tends to have better color development.

[0205] There is no particular upper limit to the content of the coloring material, but it is preferably 20% by mass or less relative to the total amount of the ink composition, more preferably 15% by mass or less, even more preferably 10% by mass or less, even more preferably 7% by mass or less, and particularly preferably 5% by mass or less. If the content of the coloring material is within the above range, it tends to have better spraying stability.

[0206] 〔water〕

[0207] The ink composition used in the recording method according to this embodiment is an aqueous ink composition. "Aqueous" means that it contains at least water as a solvent component, and may also contain water as the main solvent component. The type or content of water is the same as that of the processing liquid described above, and the description is provided by replacing "processing liquid" with "ink composition".

[0208] [Water-soluble low-molecular-weight organic compounds]

[0209] The ink composition used in the recording method according to this embodiment may also contain water-soluble low-molecular-weight organic compounds. The types or contents of the water-soluble low-molecular-weight organic compounds are the same as those of the processing liquid described above, and the description will be conducted by replacing "processing liquid" with "ink composition".

[0210] The water-soluble low-molecular-weight organic compound in the ink composition preferably contains 40% by mass or less relative to the total mass of the treatment liquid. Furthermore, it preferably contains 1% by mass or more relative to the total mass of the treatment liquid. More preferably, it contains 5 to 30% by mass, more preferably 5 to 25% by mass, and particularly preferably 10 to 25% by mass.

[0211] [surfactants]

[0212] The ink composition used in the recording method according to this embodiment may also contain a surfactant. The type or content of the surfactant is the same as that of the processing liquid described above; the description will be conducted by replacing "processing liquid" with "ink composition".

[0213] [Resin particles]

[0214] The ink composition used in the recording method according to this embodiment may also contain resin particles. Resin particles can further improve the adhesion of the image formed by the ink composition adhering to the recording medium. Examples of resin particles include those composed of urethane resins, acrylic resins (including styrene-acrylic resins), fluorene resins, polyolefin resins, rosin-modified resins, terpene resins, polyester resins, polyamide resins, epoxy resins, vinyl chloride resins, vinyl chloride-vinyl acetate copolymers, and ethylene vinyl acetate resins. Among these, urethane resins, acrylic resins, polyolefin resins, and polyester resins are preferred. These resin particles are mostly processed in emulsion form, but they can also be in powder form. Furthermore, one type of resin particle or a combination of two or more can be used alone.

[0215] Carbamate resins are a general term for resins containing carbamate bonds. In addition to carbamate bonds, carbamate resins can also include polyether-type carbamate resins with ether bonds in the main chain, polyester-type carbamate resins with ester bonds in the main chain, and polycarbonate-type carbamate resins with carbonate bonds in the main chain. In addition, commercially available products can also be used as urethane resins, such as SUPER FLEX460, 460s, 840, E-4000 (trade name, manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.), REZAMINE D-1060, D-2020, D-4080, D-4200, D-6300, D-6455 (trade name, manufactured by Daiichi Seika Kogyo Co., Ltd.), TAKELAC WS-6021, W-512-A-6 (trade name, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.), SANCURE 2710 (trade name, manufactured by LUBRIZOL Co., Ltd.), PERMARIN UA-150 (trade name, manufactured by Sanyo Chemical Co., Ltd.), etc.

[0216] Acrylic resins are a general term for polymers obtained by polymerizing at least one acrylic monomer, such as (meth)acrylic acid or (meth)acrylate, as a component. Examples include resins derived from acrylic monomers and copolymers of acrylic monomers with other monomers. For example, acrylic-vinyl resins, which are copolymers of acrylic monomers and vinyl monomers, are examples. Furthermore, styrene, for example, is an example of a vinyl monomer.

[0217] Acrylamide and acrylonitrile can also be used as acrylic monomers. In resin emulsions made from acrylic resins, commercially available products can be used, such as FK-854 (trade name, manufactured by Chuo Riko Kogyo Co., Ltd.), MOWINY L952B and 718A (trade name, manufactured by Nippon Synthetic Chemical Co., Ltd.), Nipol LX852 and LX874 (trade name, manufactured by ZEON Corporation of Japan).

[0218] It should be noted that, in this specification, acrylic resin can also refer to the styrene-acrylic resin described later. Furthermore, in this specification, the term (meth)acrylic acid refers to acrylic acid or methacrylic acid.

[0219] Styrene-acrylic resins are copolymers obtained from styrene monomers and (meth)acrylic monomers. Examples include styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-acrylate copolymers, styrene-α-methylstyrene-acrylic acid copolymers, and styrene-α-methylstyrene-acrylic acid-acrylate copolymers. Styrene-acrylic resins can be commercially available, such as Joncryl 62J, 7100, 390, 711, 511, 7001, 631, 632, 741, 450, 840, 74J, HRC-1645J, 734, 852, 7600, 775, 537J, 1535, PDX-7630A, 352J, 352D, PDX-7145, 538J, 7640, 7641, 631, 790, 780, 7610 (trade names, manufactured by BASF), MOWINYL 966A, 975N (trade names, manufactured by Nippon Synthetic Chemicals Co., Ltd.), VINYBLAN 2586 (manufactured by Nissin Chemical Co., Ltd.), etc.

[0220] Polyolefin resins contain olefins such as ethylene, propylene, and butene in their structural backbone, and well-known olefins can be appropriately selected. Commercially available products can also be used as olefin resins, such as Arrow Base CB-1200 and CD-1200 (trade name, manufactured by Unitika Co., Ltd.).

[0221] 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. Furthermore, it is particularly preferred to be 50°C or higher and 80°C or lower. By keeping the glass transition temperature (Tg) of the resin particles within the above range, there is a tendency for superior durability and clogging resistance. The glass transition temperature is measured, for example, using a differential scanning calorimeter "DSC7000" manufactured by HITACHI HI-TECH SCIENCE Co., Ltd., according to JIS K7121 (Method for Determination of Transition Temperature of Plastics).

[0222] The volume average particle size 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 size can be determined by the method described above.

[0223] The acid value of the resin particles is preferably 50 mg KOH / g or less, more preferably 30 mg KOH / g or less, even more preferably 20 mg KOH / g or less, and particularly preferably 10 mg KOH / g or less. Furthermore, the lower limit of the acid value is 0 mg KOH / g or more, preferably 5 mg KOH / g or more, and more preferably 10 mg KOH / g or more. In this case, image quality is excellent, and therefore preferred. The acid value can be determined by the method described above.

[0224] When the ink composition contains resin particles, the content relative to the total mass of the ink composition, is 0.1% by mass or more and 10% by mass or less in terms of solids, preferably 0.5% by mass or more and 5% by mass or less, more preferably 1% by mass or more and 5% by mass or less.

[0225] [Other ingredients]

[0226] The ink composition used in the recording method according to this embodiment may also contain other components. These other components are the same as those in the processing liquid described above; the explanation will be conducted by replacing "processing liquid" with "ink composition".

[0227] 1.3 Air supply process

[0228] The recording method described in this embodiment includes an air supply step for supplying air to the recording medium in the above-mentioned processing liquid adhesion step and ink adhesion step.

[0229] In the liquid coating process and the ink coating process, the so-called air supply process that supplies air to the recording medium simply means that the recording medium supported by the recording medium support part such as the printing plate is subjected to the air supply process at the same time as the liquid coating process and the ink coating process, and the transport process is performed near the recording medium supported by the recording medium support part.

[0230] The air supply process applies air to the recording medium on the impression plate located opposite the inkjet head. This process simply involves supplying air to the recording medium located where the processing liquid and ink adhesion processes are performed, thereby promoting the drying of the processing liquid and ink adhered to the recording medium. More specifically, it simply involves supplying air to remove the solvent components of the processing liquid or ink evaporating from the recording medium, thus promoting evaporation.

[0231] For example, air can be supplied not only to the vicinity of the surface of the recording medium, but also to a location far from the surface of the recording medium.

[0232] The air supply process can be performed simultaneously with, before, or after the time point at which the processing liquid and ink composition are applied to the recording medium, preferably after the application time point.

[0233] In the air supply process, the preferred air velocity is 0.5 m / s or higher. More preferably, it is 1.0 m / s or higher, more preferably 1.5 m / s or higher, even more preferably 2.0 m / s or higher, and still more preferably 2.5 m / s or higher. If the air velocity is within the above range, the drying performance is further improved, and the image quality (uneven bleeding) tends to be superior. Furthermore, it can sometimes diffuse the vapor of ink components, reducing condensation on the nozzle surface. It should be noted that the upper limit of the air velocity is not particularly limited, but it is preferably 20 m / s or lower, more preferably 15 m / s or lower, even more preferably 10 m / s, and particularly preferably 5 m / s or lower.

[0234] The wind speed is the maximum wind speed measured within the range of the recording medium located at the position supported by the printing plate, from the surface of the recording medium to the height of the carriage on which the inkjet head is mounted.

[0235] The air temperature supplied in the air supply process is preferably below 80°C. More preferably, it is below 45°C, even more preferably below 40°C, more preferably below 35°C, even more preferably below 30°C, and still more preferably below 25°C. Unheated air is preferred, and particularly room temperature air is preferred. The lower limit of the above air temperature is not particularly limited, but it is preferably above 10°C, even more preferably above 15°C. Furthermore, it is preferably above 20°C.

[0236] It should be noted that the air supplied in the air supply process is preferably at room temperature, but hot air can also be used. The temperature of the hot air is preferably below 80°C, more preferably 80–35°C, and even more preferably 60–35°C. The air temperature is measured at the location where the wind speed is measured, under conditions unaffected by heat other than the temperature of the wind itself.

[0237] The air supply process can be performed using an air supply mechanism that supplies air to the vicinity of the recording surface of the recording medium supported by the impression plate. For example, a fan can be used.

[0238] 1.4 Secondary drying process

[0239] The recording method described in this embodiment may further include a secondary drying process of heating the recording medium after the aforementioned processing liquid adhesion process and ink adhesion process. The secondary drying process can be performed, for example, using a suitable heating mechanism. The secondary drying process is performed, for example, by a post-heater (equivalent to heater 59 in the example of the serial inkjet recording device described later), preferably after passing through the impression plate. Furthermore, the heating mechanism is not limited to the heating mechanism provided with inkjet recording devices, and other drying mechanisms can also be used. Since the resulting image can be dried more thoroughly and fixed more completely, the recorded material can be made usable as soon as possible.

[0240] The surface temperature of the recording medium reached by the heating in the secondary drying process is preferably 50°C or higher. More preferably, it is 60.0°C or higher and 120.0°C or lower, more preferably 70.0°C or higher and 100.0°C or lower, more preferably 70.0°C or higher and 90°C or lower, and even more preferably 70°C or higher and 80°C or lower. The surface temperature of the recording medium reached by the heating in the secondary drying process is particularly preferably 70°C or higher. If the temperature of the recording medium is within this range, it tends to enable the film formation and planarization of resin particles, and to allow the obtained image to dry more thoroughly and be fixed more completely.

[0241] 1.5 Other processes

[0242] The recording method of this embodiment may also include a single drying step. The single drying step includes the air supply step described above, but may also include a single drying step other than the air supply step described above.

[0243] A primary drying process is a process that dries the recording medium during the aforementioned treatment liquid adhesion process and ink adhesion process.

[0244] A drying process other than the air supply process can be performed by using a drying mechanism, in addition to the method of stopping recording and placing the recording medium. As a method of drying using a drying mechanism, methods such as irradiating the recording medium with heat-generating radiation (infrared rays, etc.) (radiative type), using a component that contacts the recording medium and transfers heat to the recording medium (conductive type), and combinations of two or more of these methods can be listed.

[0245] In a single drying process, the use of a drying mechanism that heats the recording medium is specifically referred to as a single heating process. For example, in the drying mechanism described above, this corresponds to a conductive or radial drying mechanism.

[0246] Even when a single drying process is performed, as described above, the surface temperature of the recording medium to which the material is attached is preferably below 35°C.

[0247] Furthermore, the aforementioned treatment liquid adhesion step and ink adhesion step may not be accompanied by a heating step. That is, the recording method of this embodiment preferably does not utilize a heating mechanism for heating the recording medium provided in the component supporting the recording medium, nor does it utilize a heating mechanism for heating the recording medium from above, at the location where the ink composition and treatment liquid are adhered. In this case, the surface temperature of the recording medium in the treatment liquid adhesion step and ink adhesion step tends to be low, below a predetermined temperature, resulting in better clogging recovery.

[0248] 1.6 Continuous printing time

[0249] The recording method described in this embodiment preferably involves continuous recording for 0.5 hours or more, more preferably for 1 hour or more, more preferably for 1.5 hours or more, and even more preferably for 2 hours or more. There is no particular upper limit, but continuous recording for 10 hours or less is preferred, more preferably for 7 hours or less, and particularly preferably for 5 hours or less.

[0250] When the continuous recording time is long, the clogging recovery performance tends to deteriorate. However, if it is the recording method involved in this embodiment, even with the above-mentioned continuous recording time, there is a tendency to obtain good clogging recovery performance, so it is preferred.

[0251] Continuous printing time is the time it takes to repeatedly scan and transport the recording media (sub-scanning, etc.) and continuously record multiple images. In continuous printing, lengthy maintenance tasks such as drawing ink from the inkjet head are not required. Maintenance tasks such as rinsing can be performed quickly.

[0252] 2. Recording device

[0253] One embodiment of the present invention relates to a recording apparatus that records on a recording medium using the above-described recording method, and includes the above-described processing liquid, ink composition, inkjet head for processing liquid, and inkjet head for ink.

[0254] According to the recording apparatus of this embodiment, by recording using the above-described recording method, the nozzle clogging recovery, image quality (uneven bleeding), and whitening reduction of the printed matter are excellent.

[0255] The processing liquid and ink composition of the recording device according to this embodiment are as described above, and therefore, the description is omitted. Hereinafter, an example of the recording device according to this embodiment will be described with reference to the accompanying drawings.

[0256] 2.1 Serial recording device

[0257] Figure 1 This is a schematic cross-sectional view of a serial inkjet recording device 19. Figure 2 It means Figure 1 A perspective view of an example of the structure surrounding the carriage of the inkjet recording device 19. (See diagram below.) Figure 1 , 2 As shown, the inkjet recording device 19 includes an inkjet head 29, an IR heater 391, an impression plate heater 49, a heater 59, a cooling fan 69, a preheater 79, a ventilation fan 89, a carriage 99, an impression plate 119, a carriage moving mechanism 139, a transport unit 149, and a control unit CONT. The inkjet recording device 19... Figure 2The control unit CONT shown controls the overall operation of the inkjet recording device 19.

[0258] The inkjet head 29 includes a processing liquid inkjet head 29a for ejecting processing liquid and an ink inkjet head 29b for ejecting ink composition. By ejecting the processing liquid and ink composition from the nozzles of each inkjet head and allowing them to adhere, recording can be performed on the recording medium M.

[0259] In this embodiment, the inkjet head 29 is a serial inkjet head that performs multiple scans relative to the recording medium M in the main scanning direction, causing the ink composition and processing liquid (hereinafter also referred to as "ink, etc.") to adhere to the recording medium M. The inkjet head 29 is mounted on... Figure 2 The inkjet head 29 is mounted on the carriage 99 shown. Through the action of the carriage moving mechanism 139, which moves the carriage 99 in the media width direction of the recording medium M, the inkjet head 29 performs multiple scans relative to the recording medium M in the main scanning direction. The media width direction refers to the main scanning direction of the inkjet head 29. Scanning in the main scanning direction is also called the main scan.

[0260] Figure 3 This indicates that the inkjet head 29a for ejecting the processing liquid is arranged laterally relative to the transport direction (T2 direction) of the recording medium M at the same position as the ink inkjet head 29b for ejecting the ink composition. In this case, when the nozzle array of the processing liquid of the inkjet head 29a is projected along the head movement direction (MS), it is configured to completely overlap with the nozzle array of the ink of the ink inkjet head 29b in the nozzle array direction (SS).

[0261] If arranged in this way, the processing liquid adhesion step and the ink adhesion step in the above-described recording method can be performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium, and by using the same scan to adhere the processing liquid and ink composition to the same scan area (completely simultaneous jetting). It should be noted that... Figure 3 The nozzle array shown is the array of nozzles that eject ink, etc., from each inkjet head.

[0262] Figure 4 This indicates an arrangement in which the inkjet head 29a for ejecting the processing liquid and the inkjet head 29b for ejecting the ink composition relative to the transport direction (T2 direction) of the recording medium M are arranged laterally at the same position in the upstream 1 / 4 of the transport direction of the recording medium M. In this case, when the nozzle array of the processing liquid of the inkjet head 29a is projected along the head movement direction (MS), the ink nozzle array of the inkjet head 29b is configured such that the nozzle array of the ink overlaps with the upstream 1 / 4 of the transport direction of the recording medium M in the nozzle array direction (SS).

[0263] If arranged in this way, the processing liquid adhesion step and the ink adhesion step in the above-mentioned recording method can be performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium, and the processing liquid and ink composition are adhered to the same scanning area by the same scanning (forward spraying). It should be noted that Figure 4 The nozzle array shown is the array of nozzles that eject ink and other substances from each inkjet head.

[0264] Figure 5 This indicates that the inkjet head 29a for ejecting the processing liquid has a portion that is not laterally arranged at the same position as the ink inkjet head 29b for ejecting the ink composition, relative to the transport direction (T2 direction) of the recording medium M. In this case, when the nozzle array of the processing liquid in the inkjet head 29a is projected along the head movement direction (MS), there is no overlap in the nozzle array direction (SS) with the nozzle array of the ink in the ink inkjet head 29b.

[0265] If arranged in this way, the processing liquid adhesion process and the ink adhesion process are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium, thus preventing the processing liquid and ink composition from adhering to the same scanning area using the same scan. This is not the recording method of this embodiment.

[0266] The main scanning direction is the direction in which the carriage 99, on which the inkjet head 29 is mounted, moves. Figure 1 In the diagram, the arrow SS indicates the direction in which the recording medium M is transported, i.e., the direction in which the sub-scanning directions intersect. Figure 2 In this diagram, the width direction of the recording medium M, denoted by S1-S2, is the main scanning direction MS, and the direction denoted by T1→T2 is the sub-scanning direction SS. It should be noted that a single scan is performed in either the main scanning direction (arrow S1 or arrow S2). Then, the recording medium M is recorded by repeatedly performing the main scan of the inkjet head 29 and the sub-scans that transport the recording medium M. In other words, the processing liquid adhesion process and the ink adhesion process are performed through multiple main scans by the inkjet head 29 moving in the main scanning direction and multiple sub-scans by the recording medium M moving in the sub-scanning direction intersecting with the main scanning direction.

[0267] The cartridge 129, which supplies ink or the like to the inkjet head 29, comprises multiple independent cartridges. The cartridge 129 is detachably mounted to the carriage 99 on which the inkjet head 29 is mounted. Each of the multiple cartridges can be filled with different types of ink or the like, and ink or the like is supplied from the cartridge 129 to each nozzle. It should be noted that in this embodiment, an example of the cartridge 129 being mounted on the carriage 99 is shown, but this is not a limitation; it may also be located outside the carriage 99, and the ink or the like may be supplied to each nozzle via a supply pipe (not shown).

[0268] The inkjet head 29 can eject ink droplets using conventionally known methods. In this embodiment, a method of ejecting droplets using the vibration of a piezoelectric element is used, that is, an ejection method that uses the mechanical deformation of an electrostrictive element to form ink droplets.

[0269] The inkjet recording apparatus 19 includes a ventilation fan 89, an IR heater 391, and an impression plate heater 49 for drying ink ejected from the inkjet head 29 and adhering to the recording medium M. By appropriately combining these ventilation fan 89, IR heater 391, and impression plate heater 49, a single drying process can be performed. In a single drying process, it is not necessary to heat the recording medium M; the ventilation fan 89 can be used alone as a method of providing airflow at room temperature.

[0270] It should be noted that if an IR heater 391 is used, the recording medium M can be radially heated from the inkjet head 29 side via infrared radiation. Therefore, the inkjet head 29 can also be easily heated simultaneously, but compared to heating from the back of the recording medium M, such as from the impression plate heater 49, the temperature rise is unaffected by the thickness of the recording medium M. Furthermore, various fans (e.g., ventilation fan 89) are provided, which blow hot air or air at the same temperature as the ambient temperature onto the recording medium M to dry the ink and other substances on the recording medium M.

[0271] The impression plate heater 49 can heat the recording medium M via the impression plate 119 at a position opposite to the inkjet head 29, so that the ink or the like ejected from the inkjet head 29 can be dried as early as possible from the point when it adheres to the recording medium M. The impression plate heater 49 can heat the recording medium M by conduction, thereby allowing the ink or the like to adhere to the heated recording medium M.

[0272] It should be noted that, whether or not heating is performed using the IR heater 391 and the imprint plate heater 49, the upper limit of the surface temperature of the recording medium M is preferably 45°C or less, more preferably 40°C or less, even more preferably 35°C or less, and even more preferably 30°C or less. Furthermore, it is preferably 25°C or less. The lower limit is preferably 20°C or more, more preferably 30°C or more, and even more preferably 35°C or more.

[0273] In the recording apparatus of this embodiment, from the viewpoint of improving clogging recovery, it is preferable that drying accompanied by heating is not performed in the attachment process, and it is preferable that the IR heater 391 or the imprint plate heater 49 is not included.

[0274] Heater 59 is used to dry and cure ink or other substances adhering to the recording medium M; that is, it is a heater for secondary heating or secondary drying. Heater 59 can be used in a secondary drying process. By heating the recording medium M on which the image is recorded using heater 59, the moisture and other substances contained in the ink evaporate and disperse more rapidly. In this way, the ink film on the recording medium M is firmly fixed or adhered, exhibiting excellent film-forming properties, and high-quality images can be obtained in a short time.

[0275] The upper limit of the surface temperature of the recording medium M heated by the heater 59 is preferably 120°C or less, more preferably 100°C or less, and even more preferably 80°C or less. Furthermore, the lower limit of the surface temperature of the recording medium M is preferably 50°C or more, more preferably 60°C or more, and even more preferably 70°C or more. By keeping the temperature within this range, there is a tendency to obtain high-quality images in a short time.

[0276] The inkjet recording device 19 may also include a cooling fan 69. After the ink or the like recorded on the recording medium M is dried, the ink or the like on the recording medium M is cooled by the cooling fan 69, thereby enabling the formation of an ink coating film with good adhesion on the recording medium M.

[0277] Additionally, the inkjet recording apparatus 19 may also include a preheater 79 for preheating the recording medium M before applying ink or the like to it. Furthermore, the inkjet recording apparatus 19 may also include a ventilation fan 89 to more effectively dry the ink or the like adhering to the recording medium M.

[0278] Below the carriage 99 are: an impression plate 119 supporting the recording medium M; a carriage moving mechanism 139 for moving the carriage 99 relative to the recording medium M; and a transport unit 149, which is a roller for transporting the recording medium M in the sub-scanning direction. The operation of the carriage moving mechanism 139 and the transport unit 149 is controlled by the control unit CONT.

[0279] 2.2 Horizontal Recording Device

[0280] Figure 6 This is a schematic front view illustrating an example of a landscape recording device. It should be noted that... Figure 6 as well as Figure 7To clarify the configuration of the various parts of the device, the XYZ orthogonal coordinates with the Z-axis as the vertical axis are also recorded. Furthermore, in the following explanation, the direction in which each coordinate axis (arrow) points is appropriately treated as positive, and its opposite direction is appropriately treated as negative. It should be noted that... Figure 6 The recording device shown is designed such that the recording medium is transported in the direction along the axis of the scanning direction, and is therefore also specifically called a horizontal recording device.

[0281] The recording device 100 includes: a host device 200 that generates printing data based on image data (bitmap data) received from an external device such as a personal computer; and a printer unit 300 that prints images based on the printing data received from the host device 200. The printer unit 300 prints images on the surface of a long sheet S using an inkjet method while simultaneously conveying the sheet S in a roll-to-roll manner.

[0282] like Figure 6 As shown, the printer unit 300 includes a main body housing 1 with a generally rectangular parallelepiped shape. Inside the main body housing 1 are arranged: a feeding unit 2, which feeds the sheet S from a roller R1 on which the sheet S is wound; a printing chamber 3, which sprays ink onto the surface of the fed sheet S for printing; a drying unit 4, which dries the sheet S with ink adhering to it; and a winding unit 5, which winds the dried sheet S onto a roller R2.

[0283] More specifically, the main housing 1 is divided vertically along the Z-axis by a flat plate-shaped base 6 arranged parallel to the XY plane (i.e., horizontally), with the upper side of the base 6 forming the printing chamber 3. Approximately in the center of the printing chamber 3, an impression plate 30 is fixed to the upper surface of the base 6. The impression plate 30 is rectangular and supports the sheet S from below via its upper surface, which is parallel to the XY plane. Then, the recording unit 31 prints onto the surface of the sheet S supported on the impression plate 30.

[0284] On the other hand, a feed section 2, a drying section 4, and a winding section 5 are arranged on the lower side of the base 6. The feed section 2 is positioned on the lower side of the negative X-axis relative to the imprint plate 30. Figure 6 (Located diagonally to the left and below), it has a rotatable feed shaft 21. The sheet S is wound around this feed shaft 21, thereby supporting the roller R1. On the other hand, the take-up section 5 is positioned below the impression plate 30 in the positive X-axis direction ( ). Figure 1 The section located diagonally to the right of the printing plate 30 has a rotatable take-up shaft 51. Sheet S is wound onto this take-up shaft 51, and roller R2 is supported. The drying section 4 is positioned directly below the printing plate 30, between the feed section 2 and the take-up section 5 in the X-axis direction.

[0285] Furthermore, the sheet S fed from the feed shaft 21 of the feed section 2 is guided by rollers 71-77 as it passes sequentially through the printing chamber 3 and the drying section 4, and is then wound by the winding shaft 51 of the winding section 5. It should be noted that rollers 72 and 73 are arranged vertically (i.e., horizontally) in the X-axis direction, clamping the impression plate 30, and their positions are adjusted so that their tops are at the same height as the upper surface of the impression plate 30 (the surface supporting the sheet S). Therefore, the sheet S wound on roller 72 moves horizontally (in the X-axis direction) while sliding in contact with the upper surface of the impression plate 30 before reaching roller 73.

[0286] In printing chamber 3, printing processing of sheet S is performed by recording unit 31 disposed on the upper side of impression plate 30. Recording unit 31 prints an image on the surface of sheet S by spraying a processing liquid and ink composition onto the surface of sheet S. Here, at the end in the negative X-axis direction within printing chamber 3 ( Figure 6 The left end of the sheet S is provided with a cartridge mounting part 8, on which a processing liquid cartridge 81 for storing the processing liquid and a plurality of ink cartridges 82 for storing the ink composition are detachably mounted. In addition, the recording unit 31 can spray the processing liquid supplied from the processing liquid cartridge 81 and the ink composition supplied from the ink cartridges 82 onto the surface of the sheet S by inkjet.

[0287] Figure 7 This is a bottom view that partially represents the structure of the recording unit. Here, we use... Figure 6 as well as Figure 7 The recording unit 31 is described in detail below. This recording unit 31 includes a carriage 32, a flat support plate 33 mounted on the lower surface of the carriage 32, and inkjet heads 34 and 35 for processing liquid mounted on the lower surface of the support plate 33. On the lower surface of the support plate 33, four inkjet heads 35 and one processing liquidjet head 34 are arranged at equal intervals along the X-axis. In each of the inkjet heads 34 and 35, multiple nozzles N (nozzle arrays) are arranged parallel along the Y-axis. Then, the processing liquidjet head 34 ejects processing liquid from the nozzle N, and the four inkjet heads 35 eject inks of different colors from the nozzle N, i.e., ink compositions.

[0288] The length of the nozzle array in the Y-axis direction of the inkjet head 34 for the processing liquid and the inkjet head 35 for the ink is preferably greater than or equal to the length in the Y-axis direction of the sheet S (recording medium). With an inkjet head of such length, recording can be performed in a single pass with excellent recording speed, but due to the increased ink adhesion, uneven bleeding is more likely to occur. In contrast, the recording apparatus according to this embodiment, using the above-described recording method, tends to achieve excellent image quality (even with single-pass recording) even when recording in a single pass.

[0289] exist Figure 7 In the process of projecting the nozzle array of the processing liquid of the inkjet head 34 along the head movement direction (X-axis direction), it is configured to completely overlap with the nozzle array of the ink of the inkjet head 35 in the nozzle array direction (Y-axis direction).

[0290] If arranged in this way, the processing liquid attachment step and the ink attachment step in the above recording method can be performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium, and the processing liquid and ink composition can be attached to the same scanning area by using the same scan (completely simultaneous spraying).

[0291] return Figure 6 Continuing the explanation. The carriage 32 of the recording unit 31, configured as described above, can move integrally with the support plate 33, the inkjet head 34 for the processing liquid, and the inkjet head 35 for the ink. That is, an X-axis guide rail 37 extending parallel to the X-axis direction is provided inside the printing chamber 3, and the carriage 32 moves along the X-axis guide rail 37 in the X-axis direction when driven by the X-axis motor.

[0292] Then, while the recording unit 31 moves the carriage 32 in the X-axis direction (main scanning direction) above the impression plate 30 (scanning), it ejects processing liquid from the processing liquid inkjet head 34 and ink from the ink inkjet head 35. Using the same scan, the processing liquid and ink composition adhere to the same scanning area, thereby printing an image on the surface of the sheet S, which is stopped on the upper surface of the impression plate 30. Thus, a two-dimensional image of one frame length, scanned in the X-axis direction, is printed on the surface of the sheet S along the length of the nozzle array in the Y direction. Furthermore, the coloring material of the ink constituting the two-dimensional image is agglomerated by the action of the processing liquid and fixed onto the surface of the sheet S.

[0293] While intermittently moving the sheet S along the X-axis, the process of printing one frame as described above is repeatedly performed. Specifically, a defined area encompassing approximately the entire upper surface of the impression plate 30 becomes the printing area. Then, the sheet S is intermittently fed along the X-axis in units of a distance (intermittent transport distance) corresponding to the length of this printing area along the X-axis, and one frame of printing is performed on the sheet S that stops on the upper surface of the impression plate 30 during intermittent transport. In other words, once the printing of one frame of the sheet S that stops on the impression plate 30 is completed, the sheet S is transported intermittently along the X-axis for a distance, and the unprinted side of the sheet S stops on the impression plate 30. Next, one frame of printing is performed again on this unprinted side, and when this printing is completed, the sheet S is again transported intermittently along the X-axis for a distance. This series of actions is then repeated.

[0294] One frame can also be printed in a single scan. In this case, the number of scans is one. Alternatively, one frame can be printed in two or more scans. In this case, the recording medium is not transported during the two or more scans for printing one frame. The recording medium is transported after the printing of one frame.

[0295] It should be noted that, in order to keep the sheet S, which stops on the upper surface of the impression plate 30 during intermittent transport, flat, the impression plate 30 may also be equipped with a mechanism for sucking up the sheet S that stops on its upper surface. Specifically, a plurality of suction holes (not shown) are provided on the upper surface of the impression plate 30, and a suction part 38 is installed on the lower surface of the impression plate 30. Furthermore, by operating the suction part 38, a negative pressure is generated in the suction holes on the upper surface of the impression plate 30, and the sheet S is sucked onto the upper surface of the impression plate 30. In addition, during the period when the sheet S is stopped on the impression plate 30 for printing, the sheet S is kept flat by sucking it up by the suction part 38. On the other hand, when printing is finished, the suction part 38 stops sucking up the sheet S, thereby enabling smooth transport of the sheet S.

[0296] It should be noted that a heater 39 may also be installed on the lower surface of the printing plate 30. This heater 39 can heat the printing plate 30 to a specified temperature (e.g., 30°C) as needed. Thus, the sheet S can be configured such that while undergoing printing processing by the inkjet head 34 for processing liquid and the inkjet head 35 for ink, it is dried once by the heat of the printing plate 30.

[0297] Alternatively, in the recording apparatus according to this embodiment, the recording medium can also be heated at a location where the ink composition adheres, such as on the impression plate 30, using a heating mechanism (e.g., heater 39) for heating the recording medium, or a heating mechanism (not shown) for heating the recording medium from above, provided in the component supporting the recording medium. Examples of heating mechanisms for heating the recording medium from above include, for instance, a blower or an IR heater.

[0298] Furthermore, even under conditions where ink adheres, the surface temperature of the recording medium can be related to... Figure 1 The recording device is the same as that used in the example.

[0299] Therefore, the surface temperature of the recording medium when ink adheres is easily kept below 35°C, which tends to result in better clogging recovery.

[0300] Thus, the sheet S, having received one frame of printing, moves from the printing plate 30 to the drying section 4 as the sheet S is intermittently conveyed. The drying section 4 utilizes air heated for drying to perform a post-heating process that completely dries the processing liquid or ink composition that falls on the sheet S.

[0301] In the drying section 4, the surface temperature reached by the sheet S is equal to... Figure 1 The recording device can be the same as the example, preferably heated to 30.0°C or higher and 120.0°C or lower, more 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.

[0302] Then, the dried sheet S arrives at the winding section 5 as the sheet S is intermittently conveyed, and is wound up as roller R2.

[0303] 3. Example

[0304] The present invention will be described in more detail below by way of examples, but the invention is not limited to these examples. Unless otherwise specified, "%" refers to a mass standard.

[0305] 3.1 Preparation of the processing solution and ink composition

[0306] The processing liquids and ink compositions used in each embodiment or comparative example are described in Table 1 (for the processing liquids). Figure 8 The composition is obtained by mixing the various components. For ink compositions, see Table 2 ( Figure 9 The composition is obtained by mixing the various components. It should be noted that the composition in Tables 1 and 2 is expressed as mass % . Additionally, the coloring material (pigment) and resin particles in the tables represent solid components (active ingredients). Pure water is added to make the total mass of the treatment solution or ink 100% by mass.

[0307] It should be noted that in the ink composition, the aqueous pigment dispersion is prepared in advance as follows and used for ink preparation.

[0308] In a reaction vessel equipped with a reflux pipe, gas introduction device, thermometer, and stirrer, 198.2 parts of diethylene glycol monobutyl ether, 1.0 part of iodine, 3.7 parts of 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile), and 66.1 parts of tricyclodecyl methacrylate were added, followed by 0.17 parts of diphenylmethane as a catalyst. Polymerization was carried out at 45°C for 5 hours while nitrogen was purging, yielding a solution of polymer block A.

[0309] Next, the polymerization temperature was lowered to 40°C, and 44.0 parts of tricyclodecyl methacrylate, 17.2 parts of methacrylic acid, and 1.2 parts of 2,2'-azobis(4-methoxy-2,4-dimethylpentanonitrile) were added to the solution of the A polymer block obtained above. Polymerization was then carried out for 4 hours, followed by heating to 70°C and polymerization for 1 hour to form the B polymer block, resulting in a solution of the AB block polymer.

[0310] After cooling the solution of the AB block polymer obtained above, 66.1 parts of diethylene glycol monobutyl ether were added, and the mixture was dried at 150°C for 1 hour to obtain a polymer with a solid content of 33.0%.

[0311] 341 parts of the above polymer, 163.6 parts of butylcarbitol, and 450 parts of CI Pigment Blue 15:3 (as a cyan pigment) or CI Pigment Black 7 (as a black pigment) were mixed and stirred using a disperser. Next, the pigments were thoroughly dispersed using a horizontal media disperser to obtain an oily pigment dispersion. Then, while stirring 700 parts of the obtained oily pigment dispersion using a disperser, a mixture of 4.0 parts of potassium hydroxide and 341 parts of water was slowly added to neutralize and induce a phase inversion. Finally, the pigments were again thoroughly dispersed using a horizontal media disperser to obtain an aqueous pigment dispersion.

[0312] Regarding Tables 1 and 2 ( Figure 8 The following is a supplementary explanation of the record of ,9).

[0313] <Water-soluble low-molecular-weight organic compounds>

[0314] PG (Propylene glycol, standard boiling point 188℃, liquid at 25℃)

[0315] ·1,2HD (1,2-hexanediol, standard boiling point 223℃, liquid at 25℃)

[0316] <surfactants>

[0317] • BYK-348 (trade name manufactured by BYK-Chemie JAPAN Co., Ltd., a silicone-based surfactant)

[0318] <Flocculant>

[0319] ·CATIO MASTER PD-7 (trade name manufactured by Yokkaichi Synthetic Co., Ltd., amine-epoxychloropropane copolymer cationic resin)

[0320] <Resin Particles>

[0321] Joncryl 631 (trade name manufactured by BASF JAPAN Co., Ltd., a styrene-acrylic resin emulsion)

[0322] 3.2 Recording Conditions

[0323] The records in the evaluation experiment are subject to the following conditions.

[0324] Printing press: to be discussed later

[0325] Resolution: 1200×1200dpi

[0326] Printed design: Solid design (cyan or black)

[0327] Number of scans: Tables 3 and 4 Figure 10 , Figure 11 Recorded in

[0328] Paper surface temperature: Tables 3 and 4 Figure 10 , Figure 11 Recorded in

[0329] Secondary drying temperature: 70℃

[0330] Recording media: Tables 3 and 4 Figure 10 , Figure 11 This is recorded in [the relevant document]. The types of recording media will be described later.

[0331] Continuous printing time: Tables 3 and 4 Figure 10 , Figure 11 As recorded in [the document]. The duration of continuous recording, which is achieved through scanning and the transport of the recording medium.

[0332] It should be noted that "paper temperature" refers to the surface temperature of the recording medium located opposite the inkjet head. Additionally, "secondary drying temperature" refers to the surface temperature of the recording medium after it has undergone a secondary drying process following the impression plate.

[0333] It should be noted that Tables 3 and 4 ( Figure 10 , Figure 11 In the nozzle arrangement, the various arrangements are as follows.

[0334] "Arrangement 1": As a printing press (recording device), a modified L-4533AW (manufactured by Seiko Epson Corporation) was prepared. It adopted... Figure 6 The image shows a horizontal recording device. The inkjet head is... Figure 7 The inkjet head arrangement described herein is such that the processing liquid adhesion process and the ink adhesion process are performed in the same scan, so that the processing liquid and ink composition are adhered to the same scan area (completely simultaneous spraying).

[0335] "Arrangement 2": In Arrangement 1, one frame is printed by performing a scan with only the processing liquid adhering to it, followed by a scan with only the ink adhering to it. After printing one frame, the recording medium is transported, and the next frame is printed in the same way. The processing liquid adhering process and the ink adhering process are performed by using the same scan to prevent the processing liquid and ink composition from adhering to the same scan area.

[0336] "Arrangement 3": In Arrangement 1, the recording device is further modified by fixing the inkjet head near the center of the impression plate, creating a line printhead. It is a line printer that has a line printhead with a width exceeding the recording width of the recording medium. The recording method involves ejecting ink from the line printhead onto the recording medium while the recording medium is moved relative to the line printhead in a scanning direction intersecting the width direction. It should be noted that in this line printer, the printhead remains stationary and recording is performed in a single pass. During recording, the inkjet head (line printhead) does not move.

[0337] "Arrangement 4": In Arrangement 5, it is... Figure 4 The inkjet head arrangement described herein is such that the processing liquid adhesion process and the ink adhesion process are performed in the same scan, so that the processing liquid and ink composition are adhered to the same scan area (forward spraying).

[0338] "Arrangement 5": As a printing press (recording device), a modified SC-R5050 (manufactured by Seiko Epson Corporation) was prepared. It adopted... Figure 1 Such a serial recording device. The inkjet head is... Figure 3 The inkjet head arrangement described herein is such that the processing liquid adhesion process and the ink adhesion process are performed in the same scan, so that the processing liquid and ink composition are adhered to the same scan area (completely simultaneous spraying).

[0339] "Arrangement 6": In Arrangement 1, make the inkjet head... Figure 5 The inkjet head arrangement is described in the text. For the same scanning area of ​​the recording medium, a scan to adhere the processing liquid is performed first, followed by a scan to adhere the ink, and then printing is performed. The processing liquid adhesion process and the ink adhesion process are performed by using the same scan to prevent the processing liquid and ink composition from adhering to the same scanning area.

[0340] In addition, Tables 3 and 4 ( Figure 10 , Figure 11 In this context, "M1" represents PET50A (trade name manufactured by Lintec Corporation, PET film). "M2" represents Orajet 3165G-010 (trade name manufactured by ORAFOL JAPAN Corporation, vinyl chloride film). "M3" represents BR9708 (trade name manufactured by Ahlstrom Corporation, wool wallpaper, absorbent recording media).

[0341] 3.3 Evaluation Test

[0342] 3.3.1 Image quality (uneven bleeding)

[0343] The aforementioned processing liquid and ink composition (cyan ink) were filled into a recording device, and a solid cyan pattern was printed on a recording medium (adhesion amount shown in Tables 3 and 4). The printed matter was visually evaluated based on the following criteria.

[0344] (Judgment Criteria)

[0345] AA: Uneven exudation is not visible at a distance of 20cm.

[0346] A: Uneven exudation can be seen at a distance of 20cm, but not at a distance of 50cm.

[0347] B: Uneven exudation can be seen at a distance of 50cm, but not at a distance of 80cm.

[0348] C: Uneven exudation can be observed even at a distance of 80cm (NG)

[0349] 3.3.2 Image Quality (Fill Rate)

[0350] The aforementioned processing liquid and ink composition (black ink) were filled into a recording device, and black 3pt text was printed on a recording medium (adhesion amount shown in Tables 3 and 4). The printed material was visually evaluated based on the following criteria.

[0351] (Judgment Criteria)

[0352] AA: No white patches are visible at a distance of 20cm.

[0353] A: The white patches can be seen at a distance of 20cm, but not at a distance of 50cm.

[0354] B: White spots can be seen at a distance of 50cm, but not at a distance of 80cm.

[0355] C: White patches can be seen even at a distance of 80cm (NG)

[0356] 3.3.3 Recovery of Mixture Blockage

[0357] The processing liquid and ink composition obtained above were filled into the recording device, and printing was performed under the printing conditions shown in Tables 3 and 4. At this time, the printhead voltage was set to 30V, and the mist generation rate was set to high. After recording, three cleaning cycles were performed, and the final number of ink droplets from the nozzles was determined based on the following criteria. It should be noted that one cleaning cycle involves discharging 1g of ink from the nozzle array.

[0358] (Judgment Criteria)

[0359] AA: All nozzles are restored only through the pre-ejection action.

[0360] A: Clean all nozzles once to restore their function.

[0361] B: Restore all nozzles by cleaning 3 times.

[0362] C: No nozzles remain unrepaired after 3 cleaning cycles (NG)

[0363] 3.3.4 Whitening of printed materials

[0364] The above-obtained processing liquid and ink composition (black ink) were filled into the recording device, and a solid black pattern was printed on the recording medium (adhesion amount is shown in Tables 3 and 4). The printed matter was visually evaluated based on the following judgment criteria.

[0365] (Judgment Criteria)

[0366] A: The whitening of the printed material is not visible.

[0367] B: Slight whitening has occurred in the printed matter, but it is not obvious.

[0368] C: The printed material is noticeably whitened (NG)

[0369] 3.3.5 Abrasion resistance

[0370] The above-obtained treatment liquid and ink composition were filled into the recording device, and a solid pattern was printed on the recording medium (adhesion amount is shown in Tables 3 and 4). After being left at room temperature for 30 minutes, the ink-adhesive portion was cut into a rectangle of 25×150mm, and the degree of ink peeling was visually evaluated based on the following judgment criteria when rubbed 100 times with a water-wetted plain cloth and a vibration abrasion tester (load 500g).

[0371] (Judgment Criteria)

[0372] AA: No peeling

[0373] A: Less than 20% of the area was stripped away relative to the evaluation area.

[0374] B: Stripping of more than 20% but less than 50% of the evaluated area.

[0375] C: More than 50% of the area was stripped away relative to the evaluation area.

[0376] 3.4 Evaluation Results

[0377] The evaluation results are shown in Tables 3 and 4. Figure 10 , Figure 11 As shown in the figure.

[0378] From Tables 3 and 4 ( Figure 10 , Figure 11According to the results described in [the document], a recording method includes: a processing liquid adhesion step, in which a processing liquid containing a coagulant is ejected from a processing liquid inkjet head and adhered to a recording medium; and an ink adhesion step, in which an aqueous ink composition containing a coloring material is ejected from an ink inkjet head and adhered to the recording medium. The processing liquid adhesion step and the ink adhesion step are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. Using the same scan, the processing liquid and the ink composition are adhered to the same scanned area. The coagulant is a calcium salt, and the content of the calcium salt relative to the total mass of the processing liquid is less than 0.35 mol / kg. In the processing liquid adhesion step, the maximum value range of the amount of calcium salt adhered in the area of ​​the recording medium where the processing liquid and the ink composition are adhered is 0.6 μmol / inch. 2 In the following embodiments, the processing liquid adhesion process and the ink adhesion process include an air supply process for supplying air to the recording medium. In each embodiment employing the above-described recording method, the nozzle clogging recovery, image quality (suppressing uneven bleeding), and whitening reduction of the printed material are all excellent.

[0379] In contrast, in the comparative examples that do not meet the above structure, at least one of the following is poor: nozzle clogging recovery, image quality (uneven bleeding), and whitening reduction of printed matter.

[0380] It should be noted that in Reference Examples 1, 3, and 4, the processing liquid adheres before the ink composition, and the same scan is used to prevent the processing liquid and ink composition from adhering to the same scanning area. In Reference Examples 1 and 4, although the content of calcium salt relative to the total mass of the processing liquid exceeds a certain level, the nozzle clogging recovery is not poor. However, since the same scan is used to prevent the processing liquid and ink composition from adhering to the same scanning area, the time spent on recording is wasted.

[0381] Furthermore, in Reference Example 2, which uses a line printer, although the calcium salt content relative to the total mass of the processing liquid is excessive, the nozzle clogging recovery is not poor. However, during recording, the line head does not move to a position not opposite to the recording medium, which is useless.

[0382] The following can be derived from the above implementation methods.

[0383] One way to record data is as follows: A recording method has the following characteristics:

[0384] The processing liquid adhesion process involves ejecting a processing liquid containing a coagulant from an inkjet head, causing it to adhere to the recording medium; and

[0385] The ink adhesion process involves ejecting a water-based ink composition containing coloring materials from an inkjet head, allowing it to adhere to the recording medium.

[0386] The processing liquid adhesion process and the ink adhesion process are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium.

[0387] Using the same scan, the processing liquid and the ink composition are adhered to the same scan area.

[0388] The coagulant is a calcium salt.

[0389] The content of the calcium salt relative to the total mass of the treatment solution is less than 0.35 mol / kg.

[0390] In the processing liquid adhesion step, the maximum value of the calcium salt adhesion amount in the region of the recording medium where the processing liquid and the ink composition are adhered is in the range of 0.6 μmol / inch. 2 the following,

[0391] The processing liquid adhesion process and the ink adhesion process include an air supply process for supplying air to the recording medium.

[0392] Alternatively, in one of the above recording methods,

[0393] The air velocity in the air supply process is above 1.5 m / s.

[0394] Alternatively, it can be any of the above recording methods.

[0395] Recording is performed continuously for more than one hour using the recording method described above.

[0396] Alternatively, it can be any of the above recording methods.

[0397] The number of scans in which the ink composition is applied to the same scanning area is 10 or less.

[0398] Alternatively, it can be any of the above recording methods.

[0399] In the processing liquid adhesion process and the ink adhesion process, the surface temperature of the recording medium to which the ink is adhered is below 35°C.

[0400] Alternatively, it can be any of the above recording methods.

[0401] The air temperature in the air supply process is below 35°C.

[0402] Alternatively, it can be any of the above recording methods.

[0403] The calcium salt is a calcium salt of an organic acid.

[0404] One method of recording device is,

[0405] A recording device that records on the recording medium using any of the recording methods described above.

[0406] It comprises the processing liquid, the ink composition, the inkjet head for the processing liquid, and the inkjet head for the ink.

[0407] This invention is not limited to the embodiments described above and can be modified in various ways. For example, this invention includes structures that are substantially the same as those described in the embodiments, such as structures with the same function, method, and result, or structures with the same purpose and effect. Additionally, this invention includes structures that replace non-essential parts of the structures described in the embodiments. Furthermore, this invention includes structures that achieve the same effect as those described in the embodiments or structures that can achieve the same purpose. Additionally, this invention includes structures incorporating known techniques into the structures described in the embodiments.

Claims

1. A recording method, characterized in that, have: The processing liquid adhesion process involves spraying a processing liquid containing a coagulant from a processing liquid inkjet head, causing it to adhere to the recording medium. as well as The ink adhesion process involves ejecting a water-based ink composition containing coloring materials from an inkjet head, allowing it to adhere to the recording medium. The processing liquid adhesion process and the ink adhesion process are performed by scanning while moving the processing liquid inkjet head and the ink inkjet head relative to the recording medium. Using the same scan, the processing liquid and the ink composition are adhered to the same scan area. The coagulant is a calcium salt. The calcium salt content relative to the total mass of the treatment solution is less than 0.35 mol / kg, and during the treatment solution adhesion process, the maximum value of the calcium salt adhering to the area of ​​the recording medium where the treatment solution and the ink composition are adhered is within the range of 0.6 μmol / inch. 2 the following, The processing liquid adhesion process and the ink adhesion process include an air supply process for supplying air to the recording medium.

2. The recording method according to claim 1, wherein, The air velocity in the air supply process is above 1.5 m / s.

3. The recording method according to claim 1 or 2, wherein, Recording is performed continuously for more than one hour using the recording method described above.

4. The recording method according to claim 1 or 2, wherein, The number of scans in which the ink composition is applied to the same scanning area is 10 or less.

5. The recording method according to claim 1 or 2, wherein, In the processing liquid adhesion process and the ink adhesion process, the surface temperature of the recording medium to which the ink is adhered is below 35°C.

6. The recording method according to claim 1 or 2, wherein, The air temperature in the air supply process is below 35°C.

7. The recording method according to claim 1 or 2, wherein, The calcium salt is a calcium salt of an organic acid.

8. A recording device, characterized in that, Recording is performed on the recording medium using the recording method described in claim 1. It comprises the processing liquid, the ink composition, the inkjet head for the processing liquid, and the inkjet head for the ink.

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