Recording method and recording apparatus

Abstract

Provided is a recording method and a recording apparatus capable of obtaining excellent image quality, filling, and scratch resistance. The recording method performs recording by performing multiple scans and includes the following steps: a step of causing a treatment liquid containing a coagulant to adhere to a recording medium; a step of causing a colored ink composition containing a color material to be ejected from an inkjet head and adhere to the recording medium; and a step of causing a clear ink composition containing a resin to be ejected from the inkjet head and adhere to the recording medium, the colored ink composition being caused to adhere by performing two or more scans on the same scan area, in the final scan of the two or more scans, the clear ink composition being caused to adhere to the scan area to which the colored ink composition adheres by the same scan, and the amount of the clear ink composition adhered in the final scan in the area to which the colored ink composition and the clear ink composition adhere being 80% by mass or more of the total amount of the clear ink composition in the area.

Description

Technical Field

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

[0002] Inkjet recording methods have made rapid progress in various aspects, enabling the recording of high-resolution images with relatively simple devices. Among these advancements, attempts have been made to achieve superior image quality by using a processing solution that allows ink droplets to fix quickly on the recording medium (e.g., Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document 1: Japanese Patent Application Publication No. 2018-165029.

[0006] However, poor image filling occurs when areas are not fully colored by ink or when tiny, ink-free areas such as pinholes appear in the image. Furthermore, the recorded image exhibits poor abrasion resistance. Therefore, excellent image quality, excellent filling, and excellent abrasion resistance are required. Summary of the Invention

[0007] One embodiment of the recording method involved in this invention is as follows:

[0008] A recording method, wherein recording is performed on a recording medium, wherein,

[0009] The recording method involves performing multiple scans, during which the relative position of the inkjet head and the recording medium is moved while ink is ejected from the inkjet head and adhered to the recording medium.

[0010] The recording method includes the following steps:

[0011] The process of applying a treatment liquid containing a coagulant to the recording medium;

[0012] The process of ejecting a coloring ink composition containing a colorant from the inkjet head and adhering it to the recording medium; and

[0013] The process of ejecting a resin-containing transparent ink composition from the inkjet head and adhering it to the recording medium.

[0014] The coloring ink composition is adhered by performing the scan on the same scanning area more than twice.

[0015] In the final scan of two or more scans, the transparent ink composition is applied to the scanned area of ​​the recording medium where the colored ink composition is applied, using the same scan.

[0016] The amount of the transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached is more than 80% by mass of the total amount of the transparent ink composition attached in that area.

[0017] One embodiment of the recording device involved in this invention is as follows:

[0018] A recording device that uses the recording method of one of the above-described schemes to record, wherein,

[0019] It comprises the colored ink composition, the transparent ink composition, and the inkjet head. Attached Figure Description

[0020] Figure 1 This is a schematic cross-sectional view of a serial inkjet recording device.

[0021] Figure 2 This is a perspective view showing an example of the structure around the carriage of a serial inkjet recording device.

[0022] Figure 3 This is a schematic side view of an inkjet recording device that records using a lateral scanning method.

[0023] Figure 4 This is a schematic top-down view of an inkjet recording device that records using a horizontal scanning method.

[0024] Symbol Explanation

[0025] 1. Serial inkjet recording device; 2. Inkjet head; 3. IR heater; 4. Press plate heater; 5. Heating heater; 6. Cooling fan; 7. Preheater; 8. Ventilation fan; 9. Carriage; 11. Press plate; 12. Ink cartridge; 13. Carriage moving mechanism; 14. Transport unit; 300. Transverse scanning inkjet recording device; 310. Carriage moving mechanism; 311. Main scanning axis carriage moving mechanism; 312. Sub-scanning axis carriage moving mechanism; 320. Carriage; 330. Transport roller; CONT: Control unit; MS: Main scanning direction; SS: Sub-scanning direction; M: Recording medium. Detailed Implementation

[0026] The embodiments of the present invention will now be described. The embodiments described below are merely illustrative examples of the present invention. The present invention is not limited to any of the embodiments described below, and includes various modifications implemented without altering the spirit of the invention. Furthermore, not all configurations described below are necessarily essential to the present invention.

[0027] 1. Recording Method

[0028] One embodiment of the present invention relates to a recording method for recording on a recording medium, wherein recording is performed by performing multiple scans, wherein ink is ejected from the inkjet head and adhered to the recording medium while the relative position of the inkjet head and the recording medium are moved during the scans, and the recording method includes the following steps: a step of adhering a treatment liquid containing a coagulant to the recording medium; a step of ejecting a coloring ink composition containing a colorant from the inkjet head and adhering it to the recording medium; and a step of ejecting a transparent ink composition containing a resin from the inkjet head and adhering it to the recording medium, wherein the adhering of the coloring ink composition is performed by performing two or more scans on the same scanning area, and in the final scan of the two or more scans, in the scanning area where the coloring ink composition is adhered to the recording medium by the same scan, the amount of transparent ink composition adhered in the final scan in the area where the coloring ink composition and the transparent ink composition are adhered is 80% or more by mass of the total amount of transparent ink composition adhered in that area.

[0029] Attempts were made to achieve superior image quality by using a processing solution that allows ink droplets to fix quickly on the recording medium. However, poor image filling resulted in areas where the ink was not fully colored or tiny, ink-free areas such as pinholes. This is presumably because the ink droplets' fluidity is reduced due to the reaction with the processing solution, making it difficult for them to spread and wet the recording medium. Furthermore, the abrasion resistance of the recorded material with the image is also poor. This is presumably because the ink components react with the processing solution to form coarse particles, making it difficult to smooth the ink film.

[0030] Therefore, the inventors conducted in-depth research and determined that in multi-pass recording where a colored ink composition (hereinafter also referred to as "colored ink") is recorded in two or more passes in the same area, by simultaneously attaching a predetermined amount or more of a transparent ink composition (hereinafter also referred to as "transparent ink") with the colored ink in the final pass, excellent image quality and excellent caking and abrasion resistance can be obtained.

[0031] It is speculated that, since the processing liquid can also react with the transparent ink, when both colored and transparent inks are applied simultaneously, the reaction between the colored ink and the processing liquid is suppressed due to the presence of the transparent ink, thus improving the wetting and spreading of the colored ink droplets on the recording medium and improving the burial effect. Furthermore, it is speculated that by applying a predetermined amount or more of transparent ink simultaneously with the colored ink during the final stroke, the components of the transparent ink can adequately protect the colored ink coating, thereby improving abrasion resistance.

[0032] The following describes the various steps included in the recording method according to this embodiment.

[0033] 1.1 Recording Method

[0034] 1.1.1 Inkjet method

[0035] The recording method described in this embodiment is a recording method that records on a recording medium, wherein recording is performed by performing multiple scans, wherein ink is ejected from the inkjet head and adhered to the recording medium while the relative position of the inkjet head and the recording medium are moved during the scan.

[0036] Recording media

[0037] There are no particular limitations on the recording medium used in the recording method according to this embodiment. Examples include absorbent recording media such as paper, film, and cloth; low-absorbency recording media such as printing paper; and non-absorbent recording media such as metal, glass, and polymer.

[0038] Here, low-absorbency or non-absorbent recording media refers to recording media that have the property of being completely non-absorbent or almost non-absorbent of liquids. Quantitatively, non-absorbent or low-absorbency recording media refers to media that, 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 it is also used by the Japan Pulp and Paper Technology Association (JAPANTAPPI). Details of the test method are described in Standard No. 51 "Paper and Board - Liquid Absorption Test Method - Bristol Method" of "JAPAN TAPPI Pulp and Paper Test Methods 2000 Edition". In contrast, absorbent recording media refers to recording media that do not meet the criteria for non-absorbent and low-absorbent properties.

[0039] As an absorbent recording medium, there are no particular limitations; examples include ordinary paper, thick paper, and coated paper. Coated paper can be made from kraft pulp, waste paper, etc.

[0040] Examples of low-absorbency recording media include recording media with a low-absorbency coating layer on the surface, which are called coated paper recording media. For example, as recording media with paper as the substrate, examples include printing paper such as art paper, coated paper, and matte paper. When the substrate is a plastic film, examples include recording media with 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.

[0041] Examples of non-absorbent recording media include recording media in which a plastic coating is applied to a paper substrate, recording media in which a plastic film is bonded to a paper substrate, and plastic films that do not have an absorbent layer (acceptor layer). Examples of such plastics include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, and polypropylene.

[0042] In addition, the recording medium can also be colorless and transparent, translucent, colored and transparent, colored and opaque, or colorless and opaque. Furthermore, the recording medium can also be inherently colored, or translucent or transparent.

[0043] The recording medium used in the recording method according to this embodiment is preferably a low-absorbency recording medium or a non-absorbency recording medium among the aforementioned recording media. Low-absorbency or non-absorbency recording media have poor liquid absorption and poor liquid wetting and spreading, thus making them more prone to image quality and caking problems. Furthermore, they tend to have poor abrasion resistance. In contrast, the recording method according to this embodiment achieves excellent image quality, excellent caking resistance, and excellent abrasion resistance even when recording on such a medium, making it preferable.

[0044] Scanning methods

[0045] The recording method described in this embodiment records by performing multiple scans (main scans), in which the relative position of the inkjet head and the recording medium is moved while ink is ejected from the inkjet head and adhered to the recording medium.

[0046] "Moving the relative position of the inkjet head and the recording medium" can be achieved by moving the inkjet head relative to the recording medium, or by moving the recording medium relative to the inkjet head. Alternatively, it can be achieved by moving both the inkjet head and the recording medium, thereby changing their relative positional relationship.

[0047] Therefore, this scan (main scan) is, for example, in Figure 1 and Figure 2 In the serial inkjet recording apparatus 1 shown (described later), recording is performed while the carriage 9 with the inkjet head 2 moves in a direction perpendicular to the transport direction (sub-scanning direction SS) of the recording medium M (main scan direction MS). In this case, it is preferable to perform sub-scans between scans. Sub-scans are performed by moving the relative position of the inkjet head and the recording medium in a direction intersecting with the direction of the scan (main scan). Furthermore, in sub-scans, ink is not ejected from the inkjet head and adhered to the recording medium; therefore, sub-scans differ from the scan (main scan).

[0048] Additionally, this scan (main scan) is, for example, in Figure 3 and Figure 4 In the inkjet recording apparatus 300 (described later) with a horizontal scanning method as shown, recording is performed by scanning (main scan) by ejecting ink from the inkjet head while moving the carriage 320 with the inkjet head 2 (not shown) in the main scanning direction MS.

[0049] In this case, a sub-scan can also be performed between scans, with the carriage 320 moving in the sub-scanning direction SS.

[0050] exist Figure 3 and Figure 4 In this process, the length of the sub-scanning direction of the inkjet head 2 is shorter than the length of the sub-scanning direction of the recording medium M. Therefore, by performing sub-scanning, extensive recording can be performed in the sub-scanning direction of the recording medium M.

[0051] In this case, it is preferable to perform the sub-scan in such a way that the scanning areas (the areas where the inkjet head intersects with the recording medium M in a single main scan) at least partially overlap with each other in the scans before and after the sub-scan. Thus, by performing two or more scans, ink can adhere to the same areas of the recording medium.

[0052] After recording on the recording medium M is completed through multiple scans, the recording medium M is transported along the main scanning direction MS, thereby transporting a new portion of the recording medium to a position between the two transport rollers 330 for the next recording.

[0053] Alternatively, the length of the sub-scanning direction of the inkjet head 2 can be set to a length greater than or equal to the length of the sub-scanning direction of the recording medium M. In this case, even without sub-scanning, extensive recording can be performed in the sub-scanning direction of the recording medium M. Furthermore, by performing two or more scans, ink can be applied to the same area of ​​the recording medium through two or more scans. Moreover, in this case, sub-scanning can be performed between scans. This improves the recording resolution of the image in the sub-scanning direction of the recording medium M.

[0054] When ink is applied to the same area of ​​the recording medium by performing two or more scans, at least a portion of the positions of the first and second scans, when the inkjet head is projected in the main scanning direction during the scan, overlaps.

[0055] When ink is applied to the same area of ​​the recording medium through two or more scans, it is possible to separate the ink that is applied to the same area through two or more scans.

[0056] Scanning and sub-scanning can also be performed by moving the recording medium M relative to the inkjet head 2. In other words, it can be performed simply by moving the relative position of the recording medium M and the inkjet head 2.

[0057] The number of scans (also known as the number of passes) that allow ink to adhere to the same area of ​​the recording medium can be adjusted based on the distance of the sub-scan. Alternatively, the number of scans can be freely adjusted without sub-scans between scans.

[0058] 1.1.2 Ink Adhesion Method

[0059] The recording method described in this embodiment attaches a coloring ink composition by performing two or more scans (main scans) on the same scanning area. In the final scan of the two or more scans, a transparent ink composition is attached to the scanning area on the recording medium by the same scan. The amount of transparent ink composition attached to the area where the coloring ink composition and transparent ink composition are attached in the final scan is 80% or more by mass of the total amount of transparent ink composition attached to that area.

[0060] In the case where "the coloring ink composition is attached by performing the same scan (main scan) on the same scan area twice or more, and the transparent ink composition is attached to the scan area on the recording medium where the coloring ink composition is attached by the same scan in the final scan of the two or more scans," in the final main scan, the coloring ink composition and the transparent ink composition are attached to the same area on the recording medium almost simultaneously (simultaneously). It is inferred that, due to the presence of the transparent ink, the reaction between the colored ink and the processing liquid is suppressed, the wetting and spreading of the colored ink droplets on the recording medium is improved, and the burial is improved.

[0061] Such simultaneous adhesion can be performed as follows: for example, the nozzle surface of the inkjet head has a plurality of nozzle columns along the main scanning direction MS, with a plurality of nozzles arranged in the sub-scanning direction SS, the plurality of nozzle columns being configured to at least partially overlap in the sub-scanning direction SS when projected along the main scanning direction MS, and each nozzle column ejects a colored ink composition and a transparent ink composition.

[0062] Regarding this configuration of overlapping nozzles in the inkjet head, for example in Figure 1 and Figure 2In the serial inkjet recording apparatus 1 shown, the nozzle arrays (not shown) for ejecting the colored ink composition and the nozzle arrays (not shown) for ejecting the transparent ink composition can overlap 100% in the sub-scanning direction SS. However, in the final scan, the nozzle arrays for ejecting the transparent ink composition and the nozzle arrays for ejecting the colored ink composition can be configured to overlap at least partially in the sub-scanning direction SS. With such a configuration, the colored ink composition and the transparent ink composition can be applied simultaneously, at least in the final main scan.

[0063] For example, in Figure 2 In the example, if the distance of a single sub-scan is set to half the length of the sub-scanning direction of the inkjet head 2, then the same area of ​​the recording medium is scanned by two scans. Here, the inkjet head 2 has a nozzle array with multiple nozzles arranged in the sub-scanning direction, and the length of the sub-scanning direction of the inkjet head 2 means the length of the sub-scanning direction of the nozzle array.

[0064] In the case where a nozzle array for ejecting a colored ink composition has a position in the sub-scanning direction that overlaps with half of the downstream side of the sub-scanning direction, the colored ink composition is adhered to the same area of ​​the recording medium by two scans, and the transparent ink composition is adhered to the same area as the colored ink composition by the same scan as the second scan of the two scans.

[0065] By adjusting the distance of a single sub-scan, the number of scans required to ensure that the coloring ink composition adheres to the same area of ​​the recording medium can be adjusted.

[0066] By adjusting the length of the portion of the nozzle array that ejects the transparent ink composition in the nozzle array that ejects the colored ink composition that overlaps with the sub-scanning direction, it is possible to adjust which scan in multiple scans that cause the colored ink composition to adhere to the same area of ​​the recording medium, using the same scan to attach the transparent ink composition to the same area as the colored ink composition.

[0067] Additionally, for example, in Figure 3 and Figure 4 In the inkjet recording device 300 with the horizontal scanning method shown, it is also similar to... Figure 1 , 2 Similarly, there are scans that allow control over the number of scans and enable the coloring ink composition and the transparent ink composition to adhere to the same area of ​​the recording medium through the same scan.

[0068] Alternatively, the nozzle arrays (not shown) that eject the colored ink composition and the nozzle arrays (not shown) that eject the transparent ink composition can be 100% overlapped in the sub-scanning direction SS. In this case, it is possible to perform a scan with simultaneous adhesion by ejecting both the colored ink composition and the transparent ink composition from the nozzles, or to perform a scan with non-simultaneous adhesion by ejecting only the colored ink composition or the transparent ink composition from the nozzles.

[0069] It is also possible to perform two or more scans without performing sub-scans between scans. In this case, it is also possible to perform scans that allow only the coloring ink composition to adhere, and scans that allow both the coloring ink composition and the transparent ink composition to adhere simultaneously, as described above.

[0070] In doing so, it is also possible to control the number of scans and to scan the same area of ​​the recording medium by means of the same scan to make the coloring ink composition and the transparent ink composition adhere to the same area.

[0071] In cases where "the application of the coloring ink composition is performed on the same scanning area more than twice," the scan (main scan) that applies the coloring ink composition passes through the same area of ​​the recording medium more than twice. The more scans are performed, the more often the coloring ink composition can be applied to the desired area, and there is a tendency for the image quality of the resulting record to be further improved.

[0072] The recording method described in this embodiment preferably involves performing the above-described scanning (main scan) on the same scanning area no more than 5 times to adhere the coloring ink composition described later, and more preferably no more than 3 times. The more main scans performed, the better the image quality and caking tend to be; however, according to the recording method described in this embodiment, even with the above-described number of scans, excellent image quality, caking, and abrasion resistance can be obtained, which is preferred.

[0073] By ensuring that "the amount of transparent ink composition adhered to in the area where the colored ink composition and transparent ink composition are attached, and that the amount of transparent ink composition adhered in the final scan is 80% or more of the total amount of transparent ink composition adhered in that area," the components of the transparent ink can adequately protect the colored ink film, resulting in excellent abrasion resistance. Furthermore, in addition to the final scan, the colored ink composition can be fully reacted with the processing liquid, leading to excellent image quality.

[0074] From the same perspective, there is a tendency to obtain even better results. Therefore, the amount of transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached is preferably 90% or more by mass of the total amount of transparent ink composition adhered to in that area, more preferably 95% or more by mass, further preferably 98% or more by mass, and particularly preferably 100% by mass. Furthermore, this 100% by mass of total adhered amount refers to the scanning area where the colored ink composition is adhered, where the transparent ink composition is adhered to the recording medium by the same scan in the scan preceding the final scan in the two or more scans mentioned above.

[0075] 1.2 Processing liquid adhesion procedure

[0076] The recording method according to this embodiment includes a step of attaching a treatment liquid containing a coagulant to the recording medium (treatment liquid attachment step).

[0077] As a method for attaching the processing liquid to the recording medium, any one or a combination of non-contact and contact methods can be used, such as inkjet printing, coating with rollers or rods, coating the processing liquid onto the recording medium using various jets, coating by immersing the recording medium in the processing liquid, or coating the recording medium with the processing liquid using a brush. Among these, inkjet printing is preferred.

[0078] The processing liquid adhesion process is preferably performed simultaneously with or before the coloring ink adhesion process described later. When the processing liquid adhesion process is performed simultaneously with the coloring ink adhesion process, for example, when the processing liquid is ejected from the inkjet head and adhered to the recording medium, the processing liquid and the coloring ink composition can be adhered (simultaneously adhered) to the same scanning area by the same scan. Such simultaneous adhesion can be performed, for example, by having a plurality of nozzle rows on the nozzle surface of the inkjet head along the main scanning direction MS, wherein a plurality of nozzles are arranged in the sub-scanning direction SS, the plurality of nozzle rows being configured such that when projected along the main scanning direction MS, at least a portion overlaps in the sub-scanning direction SS, and each nozzle row ejects the coloring ink composition and the processing liquid.

[0079] The amount of treatment fluid adhering to the recording medium is preferably 0.1–3.0 mg / inch per unit area. 2 More preferably 0.2–2.0 mg / inch 2 Further preferred dosage is 0.2–1.5 mg / inch. 2 A preferred dosage is 0.3–1.0 mg / inch. 2 A more preferred dosage is 0.3–0.8 mg / inch. 2When the amount of treatment fluid applied is within the above-mentioned range, there is a tendency to obtain superior image quality and better caking and abrasion resistance. Furthermore, the maximum amount of treatment fluid applied in the treatment fluid application process can also be set within the above-mentioned range.

[0080] In the region where the amount of the coloring ink composition is most abundant among the areas where the processing liquid and the coloring ink composition are adhered, the total amount of processing liquid adhered relative to the total amount of the coloring ink composition is preferably 1% or more and 35% or less by mass, more preferably 2% or more and 30% or less by mass, further preferably 2% or more and 10% or less by mass, and particularly preferably 2% or more and 8% or less by mass. This tends to result in superior image quality and superior caking and abrasion resistance. Furthermore, the total amount of processing liquid adhered can be the amount of adhesion extending from the region where the amount of the coloring ink composition is most abundant to a region covering 40% by mass of the amount of adhesion in that region, the amount of adhesion extending to 60% by mass of the amount of adhesion in that region, the amount of adhesion extending to 80% by mass of the amount of adhesion in that region, or the amount of adhesion extending to 90% by mass of the amount of adhesion in that region.

[0081] Treatment fluid

[0082] The components contained in the processing liquid used in the recording method according to this embodiment will be described below. Furthermore, the processing liquid is not a coloring ink composition for coloring the recording medium, but rather an auxiliary liquid used in conjunction with the coloring ink composition. Additionally, the processing liquid may contain pigments or other colorants, but the content relative to the total mass of the processing liquid is preferably 0.2% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and the lower limit is 0% by mass. The processing liquid preferably does not contain any colorants.

[0083] coagulant

[0084] The processing liquid used in the recording method according to this embodiment contains a coagulant that causes the components of the ink (colored ink composition and transparent ink composition) to coagulate. The coagulant has the function of causing the colorant and resin to coagulate by reacting with components such as colorants and resins. Through such coagulation, for example, the color development of the colorant can be improved, the fixing properties of the resin can be improved, and / or the viscosity of the ink can be increased. However, the degree of coagulation of the colorant and resin caused by the coagulant varies depending on the type of coagulant, colorant, and resin, and can be adjusted.

[0085] The coagulant is not particularly limited and can include metal salts, inorganic acids, organic acids, cationic compounds, etc. As a cationic compound, cationic resins (cationic polymers), cationic surfactants, etc., can be used. Among these, polyvalent metal salts are preferred as metal salts, and cationic resins are preferred as cationic compounds. Therefore, as a coagulant, cationic resins, organic acids, and polyvalent metal salts are preferred in terms of particularly superior image quality, abrasion resistance, and gloss.

[0086] As a metal salt, a polyvalent metal salt is preferred, but metal salts other than polyvalent metal salts can also be used. Among these coagulants, at least one selected from metal salts and organic acids is preferred due to its excellent reactivity with the components contained in the ink. Furthermore, among cationic compounds, cationic resins are preferred due to their easy solubility in the processing liquid. In addition, multiple coagulants can be used simultaneously.

[0087] Polyvalent metal salts are compounds composed of divalent or higher metal ions and anions. Examples of divalent or higher metal ions include ions of calcium, magnesium, copper, nickel, zinc, barium, aluminum, titanium, strontium, chromium, cobalt, and iron. Among these metal ions constituting polyvalent metal salts, calcium ions and magnesium ions are preferred for their excellent cohesiveness in ink composition.

[0088] The anions constituting polyvalent metal salts are either inorganic or organic ions. That is, the polyvalent metal salts in this invention refer to salts composed of inorganic or organic ions and polyvalent metals. 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.

[0089] Furthermore, the polyvalent metal compound is preferably an ionic polyvalent metal salt, especially when the polyvalent metal salt is a magnesium salt or a calcium salt, the stability of the treatment solution is better. Additionally, the counter ion of the polyvalent metal can be any of inorganic acid anions or organic acid anions.

[0090] Specific examples of the aforementioned polyvalent metal salts include calcium carbonate, calcium nitrate, calcium chloride, calcium sulfate, magnesium sulfate, calcium hydroxide, magnesium chloride, magnesium carbonate, barium sulfate, barium chloride, zinc carbonate, zinc sulfide, aluminum silicate, calcium silicate, magnesium silicate, copper nitrate, calcium formate, calcium acetate, magnesium acetate, and aluminum acetate. These polyvalent metal salts can be used individually or in combination. Among them, calcium formate, magnesium sulfate, calcium nitrate, and calcium chloride are preferred because they ensure sufficient solubility in water and reduce residue in the treatment solution (leaving little residue). Calcium formate and calcium nitrate are more preferred. Furthermore, these metal salts may also contain hydrated water in their raw material form.

[0091] As metal salts other than polyvalent metal salts, examples include monovalent metal salts such as sodium salts and potassium salts, such as sodium sulfate and potassium sulfate.

[0092] Examples of preferred organic acids include: poly(meth)acrylic acid, acetic acid, glycolic acid, malonic acid, malic acid, maleic acid, ascorbic acid, succinic acid, glutaric acid, fumaric acid, citric acid, tartaric acid, lactic acid, sulfonic acid, phosphoric acid, pyrrolidone carboxylic acid, pyranone carboxylic acid, pyrrolic carboxylic acid, furan carboxylic acid, pyridine carboxylic acid, coumaric acid, thiophene carboxylic acid, nicotinic acid, or derivatives of these compounds, or their salts. One organic acid may be used alone, or two or more may be used simultaneously. Among the salts of organic acids, metal salts are included in the aforementioned metal salts.

[0093] Examples of inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid. Inorganic acids can be used alone or in combination with two or more.

[0094] Examples of cationic resins (cationic polymers) include: cationic urethane resins, cationic olefin resins, cationic amine resins, and cationic surfactants. Water-soluble cationic polymers are preferred.

[0095] As cationic polyurethane resins, commercially available products can be used, such as Hydron CP-7010, CP-7020, CP-7030, CP-7040, CP-7050, CP-7060, CP-7610 (trade name, manufactured by Dai Nippon Ink Chemical Industry Co., Ltd.), Superflex 600, 610, 620, 630, 640, 650 (trade name, manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.), and polyurethane emulsions WBR-2120C and WBR-2122C (trade name, manufactured by Taisei Fine Chemical Co., Ltd.).

[0096] Cationic olefin resins are resins containing olefins such as ethylene and propylene in their structural backbone, and well-known olefin resins can be appropriately selected for use. Furthermore, cationic olefin resins can also be in an emulsion state dispersed in a solvent containing water, organic solvents, etc. Commercially available products can be used as cationic olefin resins, such as ArrowBase CB-1200 and CD-1200 (trade name, manufactured by Unitika Co., Ltd.).

[0097] As cationic amine resins (cationic polymers), any resin containing an amino group in its structure can be used, and well-known amine resins can be appropriately selected. Examples include polyamine resins, polyamide resins, and polyallylamine resins. Polyamine resins are resins containing amino groups in their main structure. Polyamide resins are resins containing amide groups in their main structure. Polyallylamine resins are resins with a structure derived from allyl groups in their main structure.

[0098] In addition, examples of cationic polyamine resins include Unisense KHE103L (hexamethylenediamine / epoxychloropropane resin, a 1% aqueous solution with a pH of approximately 5.0, a viscosity of 20–50 mPa·s, and a solids concentration of 50% by mass) and Unisense KHE 104L (dimethylamine / epoxychloropropane resin, a 1% aqueous solution with a pH of approximately 7.0, a viscosity of 1–10 mPa·s, and a solids concentration of 20% by mass) manufactured by Senka Corporation. Furthermore, specific examples of commercially available cationic polyamine resins include: FL-14 (manufactured by SNF Corporation), Arafix 100, 251S, 255, 255LOX (manufactured by Arakawa Chemical Co., Ltd.), DK-6810, 6853, 6885; WS-4010, 4011, 4020, 4024, 4027, 4030 (manufactured by Starlight PMC Co., Ltd.), Papiogen P-105 (manufactured by Senka Co., Ltd.), Sumirez Resin 650(30), 675A, 6615, SLX-1 (manufactured by Taoka Chemical Co., Ltd.), CatioMaster (registered trademark) PD-1, 7, 30, A, PDT-2, PE-10, PE-30, DT-EH, EPA-SK01, TMHMDA-E (manufactured by Yokkaichi Synthetic Co., Ltd.), JetFix 36N, 38A, 5052 (manufactured by Satoda Chemical Company).

[0099] Examples of polyamine resins include polyallylamine resins. Examples of polyallylamine resins include: polyallylamine hydrochloride, polyallylamine amide sulfate, allylamine hydrochloride-diallylamine hydrochloride copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine acetate-diallylamine acetate copolymer, allylamine hydrochloride-dimethylallylamine hydrochloride copolymer, allylamine-dimethylallylamine copolymer, polydiallylamine hydrochloride, polymethyldiallylamine hydrochloride, polymethyldiallylamine amide sulfate, polymethyldiallylamine acetate, polydiallyldimethylammonium chloride, diallylamine acetate-sulfur dioxide copolymer, diallylmethylethylammonium ethyl sulfate-sulfur dioxide copolymer, methyldiallylamine hydrochloride-sulfur dioxide copolymer, diallyldimethylammonium chloride-sulfur dioxide copolymer, diallyldimethylammonium chloride-acrylamide copolymer, etc.

[0100] Examples of cationic surfactants include: primary amines, secondary amines and tertiary amine salts, alkyl amine salts, dialkyl amine salts, aliphatic amine salts, benzyl alkyl ammonium salts, quaternary ammonium salts, alkyl quaternary ammonium salts, alkylpyridinium salts, sulfonium salts, onium salts, imidazoline onium salts, etc.

[0101] A variety of these coagulants can be used. In addition, if at least one of polyvalent metal salts, organic acids, and cationic resins is selected among these coagulants, the coagulation effect is better, thus enabling the formation of images with higher image quality (especially those with good color rendering).

[0102] The total content of coagulant in the processing solution is preferably 1% by mass or more and 20% by mass or less relative to the total mass of the processing solution, more preferably 1% by mass or more and 15% by mass or less, and even more preferably 2% by mass or more and 10% by mass or less. Furthermore, when the coagulant is used in both the solution and / or the dispersion, the content as a solid component is also preferably within the above range. If the coagulant content is 1% by mass or more, there is a tendency for the coagulant to sufficiently acquire the ability to coagulate the components contained in the ink. Additionally, by keeping the coagulant content at 20% by mass or less, the solubility and dispersibility of the coagulant in the processing solution become better, and there is a tendency to improve the storage stability of the processing solution, etc.

[0103] Based on the fact that the coagulant has good solubility in the treatment solution even when the organic solvent contained in the treatment solution is highly hydrophobic, it is preferable to use a coagulant with a solubility of 1g or more relative to 100g of water at 25°C, and more preferably a coagulant with a solubility of 3g or more and 80g or less.

[0104] surfactants

[0105] The processing liquid used in the recording method according to this embodiment may contain a surfactant. The surfactant has the function of adjusting the surface tension of the processing liquid and adjusting, for example, its wettability with the recording medium. Among surfactants, acetylenic diol-based surfactants, organosilicon-based surfactants, and fluorinated surfactants are preferred.

[0106] As an alkynyl diol 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, DF110D (all trade names, manufactured by Air Products & Chemicals); Olfine B, Y, P, A, STG, SPC, E1004, E1010, PD-001, PD-002W, PD-003, PD-004, EXP.4001, EXP.4036, EXP.4051, AF-103, AF-104, AK-02, SK-14, AE-3 (all trade names, manufactured by Nissin Chemical Industries, Ltd.); Acetylenol E00, E00P, E40, E100 (all trade names, manufactured by Kawaken Fine Chemicals Co., Ltd.).

[0107] There are no particular limitations on the organosilicon surfactant, but polysiloxane compounds are preferred. There are no particular limitations on the polysiloxane compound; for example, polyether-modified organosilicon compounds can be cited. Commercially available examples of this polyether-modified organosiloxane include: 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.

[0108] As a fluorinated surfactant, fluorinated modified polymers are preferred. Specific examples include BYK-3440 (manufactured by BYK Chemie Japan), Surflon S-241, S-242, S-243 (trade names, manufactured by AGC Seimi Chemical), and Ftergent 215M (manufactured by neos).

[0109] When the treatment solution contains surfactants, it may contain a variety of surfactants. The content of surfactants in the treatment solution relative to the total mass of the treatment solution is preferably 0.1% by mass or more and 2% by mass or less, more preferably 0.4% by mass or more and 1.5% by mass or less, and even more preferably 0.5% by mass or more and 1.0% by mass or less.

[0110] organic solvents

[0111] The processing liquid used in the recording method according to this embodiment may contain an organic solvent. The organic solvent is preferably water-soluble. One function of the organic solvent is to improve the wettability of the processing liquid to the recording medium and to improve the moisture retention of the processing liquid. In addition, the organic solvent can also function as a penetrant.

[0112] Examples of organic solvents include esters, alkylene glycol ethers, cyclic esters, nitrogen-containing solvents, and polyhydroxy alcohols. Examples of nitrogen-containing solvents include cyclic amides and non-cyclic amides. Examples of non-cyclic amides include alkoxyalkylamides.

[0113] Examples of esters include glycol monomethyl ether acetate, glycol monoethyl ether acetate, glycol monobutyl ether acetate, and other glycol monoacetates, as well as glycol diacetates, diethylene glycol diacetate, propylene glycol diacetate, and other glycol diacetates.

[0114] As alkylene glycol ethers, any mono- or di-ether of an alkylene glycol is acceptable, with alkyl ethers being preferred. Specific examples include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, and other alkylene glycol monoalkyl ethers; and ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and other alkylene glycol dialkyl ethers.

[0115] Examples of cyclic esters include cyclic esters (lactones) such as β-propiolactone, γ-butyrolactone, δ-valerolactone, ε-caprolactone, and β-butyrolactone, as well as compounds in which the hydrogen atom of the methylene group adjacent to their carbonyl group is replaced by an alkyl group having 1 to 4 carbon atoms.

[0116] Examples of cyclic amides include lactams, such as 2-pyrrolidone, 1-methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1-propyl-2-pyrrolidone, 1-butyl-2-pyrrolidone, and other pyrrolidone derivatives. These are preferred in terms of promoting the solubility of the coagulant and the film formation of the resin, as described later. 2-pyrrolidone is particularly preferred.

[0117] Examples of alkoxyalkylamides include 3-methoxy-N,N-dimethylpropionamide, 3-methoxy-N,N-diethylpropionamide, 3-methoxy-N,N-methylethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-diethylpropionamide, 3-ethoxy-N,N-methylethylpropionamide, 3-n-butoxy-N,N-dimethylpropionamide, 3-n-butoxy-N,N-diethylpropionamide, and 3-n-butoxy-N,N-methylethylpropionamide.

[0118] In addition, as an alkoxyalkylamide, a compound represented by the following general formula (1) is preferred.

[0119] R 1 -O-CH2CH2-(C=O)-NR 2 R 3 ……(1)

[0120] In equation (1) above, R 1 R represents an alkyl group having 1 or more but less than 4 carbon atoms. 2 and R 3 Each can be represented independently as methyl or ethyl. "Alkyl group having 1 or more carbon atoms and 4 or fewer" can be a straight-chain or branched alkyl group, for example, it can be methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl. The compound represented by the above formula (1) can be used alone or in combination of two or more.

[0121] In addition, as a function of nitrogen-containing solvents, for example, they can improve the surface drying and fixing properties of processing liquids adhering to low-absorbency recording media.

[0122] The content of nitrogen-containing solvent relative to the total mass of the processing solution is not particularly limited, but is preferably 5% by mass or more and 30% by mass or less, more preferably 10% by mass or more and 20% by mass or less. By keeping the content within the above range, it is sometimes possible to further improve the fixing and surface drying properties of the image (especially the surface drying properties when recording in high temperature and high humidity environments).

[0123] Examples of polyhydroxy alcohols include: 1,2-alkanediols (e.g., ethylene glycol, propylene glycol (also known as propane-1,2-diol), 1,2-butanediol, 1,2-pentanediol, 1,2-hexanediol, 1,2-heptanediol, 1,2-octanediol, etc.), and polyhydroxy alcohols (polyols) other than 1,2-alkanediols (e.g., diethylene glycol, dipropylene glycol, 1,3-propanediol, 1,3-butanediol (also known as 1,3-butylenediol)). (e.g., 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 2-ethyl-2-methyl-1,3-propanediol, 2-methyl-2-propyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol, 3-methyl-1,3-butanediol, 2-ethyl-1,3-hexanediol, 3-methyl-1,5-pentanediol, 2-methylpentane-2,4-diol, trimethylolpropane, glycerol, etc.)

[0124] Examples of polyhydroxy alcohols include alkyldiols and polyols. Alkyldiols are preferably diols of alkanes having 5 or more carbon atoms. The alkanes preferably have 5 to 15 carbon atoms, more preferably 6 to 10, and even more preferably 6 to 8. 1,2-Alkyldiols are preferred.

[0125] The polyols are preferably polyols of alkanes having 4 or fewer carbon atoms, or intermolecular condensations of the hydroxyl groups of polyols of alkanes having 4 or fewer carbon atoms. The alkanes preferably have 2 to 3 carbon atoms. The polyol molecule has 2 or more hydroxyl groups, preferably 5 or less, more preferably 3 or less. When the polyol is an intermolecular condensation as described above, the number of intermolecular condensations is 2 or more, preferably 4 or less, more preferably 3 or less. The polyols can be used alone or in mixtures of two or more.

[0126] Alkanediols and polyols can primarily function as penetrating solvents and / or moisturizing solvents. However, alkanediols tend to be stronger penetrating solvents, while polyols tend to be stronger moisturizing solvents.

[0127] The content of polyhydroxy alcohols, preferably alkyldiols, relative to the total mass of the treatment solution is not particularly limited, but is preferably 5% by mass or more and 30% by mass or less, more preferably 10% by mass or more and 20% by mass or less. By keeping the content within the above range, the balance between wetting spread and drying properties is further improved, and in some cases, image quality can be further improved.

[0128] When the processing solution contains organic solvents, one organic solvent can be used alone, or two or more can be used simultaneously. Furthermore, the total content of organic solvents relative to the total mass of the processing solution is preferably 5% by mass or more and 50% by mass or less, more preferably 10% by mass or more and 45% by mass or less, even more preferably 15% by mass or more and 40% by mass or less, and particularly preferably 20% by mass or more and 40% by mass or less. By keeping the content of organic solvents within the above range, a better balance between wetting spread and drying properties is achieved, making it easier to form high-quality images.

[0129] Furthermore, the processing solution more preferably contains an organic solvent among the organic solvents exemplified above, with a standard boiling point of 150.0°C or higher and 280.0°C or lower. This allows for faster drying and fixing of the formed image.

[0130] Furthermore, the treatment solution preferably does not contain more than 1.0% by mass of polyols with a standard boiling point exceeding 280.0°C. The content of polyols with a standard boiling point exceeding 280°C in the treatment solution relative to the total mass of the treatment solution is preferably 5% by mass or less, more preferably 3% by mass or less, further preferably 1% by mass or less, particularly preferably 0.5% by mass or less, and even more particularly preferably 0.1% by mass or less. The lower limit of the content of polyols with a standard boiling point exceeding 280°C can also be 0% by mass.

[0131] This results in better image drying, faster recording, and improved adhesion to the recording medium. Furthermore, the processing solution is preferably an organic solvent (not limited to polyols) with a standard boiling point exceeding 280.0°C within the aforementioned range. Examples of organic solvents with a standard boiling point exceeding 280°C include glycerol and polyethylene glycol monomethyl ether.

[0132] water

[0133] The processing liquid used in the recording method according to this embodiment may also contain water. The processing liquid is preferably an aqueous composition. An aqueous composition means that water is one of the main solvent components. This allows for recording with reduced environmental impact and less odor.

[0134] Water is contained as the main solvent component of the treatment solution and is a component that evaporates and dissipates through drying. The water is preferably pure or ultrapure water, such as ion-exchange water, ultrafiltration water, reverse osmosis water, or distilled water, which has been thoroughly purified to remove ionic impurities. Furthermore, water sterilized by ultraviolet irradiation or the addition of hydrogen peroxide is preferred as it inhibits the growth of mold and bacteria during long-term storage of the treatment solution. The water content relative to the total amount of the treatment solution is preferably 45% by mass or more, more preferably 50% by mass or more and 98% by mass or less, and even more preferably 55% by mass or more and 95% by mass or less.

[0135] Other ingredients

[0136] The processing liquid used in the recording method according to this embodiment may contain urea, amines, sugars, etc. as additives. Examples of urea include urea, ethylidene urea, tetramethylurea, thiourea, 1,3-dimethyl-2-imidazolinone, etc.; and betaine compounds (trimethylglycine, triethylglycine, tripropylglycine, triisopropylglycine, N,N,N-trimethylalanine, N,N,N-triethylalanine, N,N,N-triisopropylalanine, N,N,N-trimethylmethylalanine, carnitine, acetylcarnitine, etc.).

[0137] Examples of amines include diethanolamine, triethanolamine, and triisopropanolamine. Ureas and amines can also function as pH adjusters.

[0138] Examples of sugars include glucose, mannose, fructose, ribose, xylose, arabinose, galactose, aldonic acid, glucosyl alcohol (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, and maltotriose.

[0139] The processing liquid used in the recording method described in this embodiment may also contain various additives such as preservatives / mildew inhibitors, rust inhibitors, chelating agents, viscosity modifiers, antioxidants, and mildew inhibitors, as needed.

[0140] physical properties

[0141] From the viewpoint of ensuring appropriate wetting and spreading properties to the recording medium, the processing liquid used in the recording method of this embodiment has a surface tension of 40 mN / m or less at 25°C, preferably 38 mN / m or less, more preferably 35 mN / m or less, and even more preferably 30 mN / m or less. Furthermore, the surface tension can be measured using an automatic surface tension meter CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.) and by confirming the surface tension when the composition wets a platinum plate at 25°C.

[0142] The processing fluid is more preferably adhered to the recording medium by inkjet printing. In this case, the viscosity at 20°C is preferably 1.5 mPa·s or more and 15 mPa·s or less, more preferably 1.5 mPa·s or more and 7 mPa·s or less, and even more preferably 1.5 mPa·s or more and 5.5 mPa·s or less. When the processing fluid is adhered to the recording medium by inkjet printing, a predetermined processing fluid adhesion area can be easily and efficiently formed on the recording medium.

[0143] 1.3 Coloring Ink Adhesion Process

[0144] The recording method according to this embodiment includes a step of ejecting a coloring ink composition containing a colorant from an inkjet head and attaching it to a recording medium (coloring ink attachment step).

[0145] The preferred amount of the coloring ink composition adhering to the recording medium is 1.0 mg / inch. 2 The above, more preferably 2.0 mg / inch 2 The above is further preferred to be 4.0 mg / inch. 2 The above is further preferred to be 6.0 mg / inch. 2 The above, especially preferred, is 8.0 mg / inch. 2 The above, and more particularly preferred, is 10.0 mg / inch. 2 That's all. Additionally, the preferred upper limit is 25.0 mg / inch. 2 The following is more preferably 20.0 mg / inch 2 The following is a further preferred dosage: 15.0 mg / inch 2 The following applies. When the amount of the coloring ink composition adhered is within the above-mentioned range, there is a tendency to obtain superior image quality and superior filling and abrasion resistance. Furthermore, the maximum amount of the coloring ink composition adhered during the coloring ink adhesion process can also be set within the above-mentioned range.

[0146] The surface temperature of the recording medium in the process of adhering the coloring ink composition is preferably 45°C or lower, more preferably 40°C or lower, even more preferably 35°C or lower, even more preferably 30°C or lower, particularly preferably 28°C or lower, and even more preferably the same as the printing ambient temperature. When the surface temperature of the recording medium in the process of adhering the coloring ink composition is within the above range, there is a tendency for better filling performance. In addition, the lower limit is preferably 20°C or higher, more preferably 25°C or higher.

[0147] Furthermore, this temperature is the surface temperature of the portion of the recording surface of the recording medium that receives the liquid during the coloring ink adhesion process, and it is the highest temperature in the recording area. It is also preferable to set the above-mentioned surface temperature during the processing liquid adhesion process and the transparent ink adhesion process.

[0148] Coloring ink composition

[0149] Hereinafter, the components contained in the coloring ink composition used in the recording method according to this embodiment will be described.

[0150] color material

[0151] The coloring ink composition used in the recording method according to this embodiment contains a colorant. Examples of colorants include dyes and pigments. Preferably, the colorant is a colored colorant such as cyan, yellow, magenta, or black.

[0152] The colorant can be either a dye or a pigment, or a mixture thereof. However, among dyes and pigments, it is more preferable to include a pigment. Pigments exhibit excellent storage stability in terms of lightfastness, weather resistance, and gas resistance; from this perspective, organic pigments are preferred.

[0153] Specifically, the pigments can include insoluble azo pigments, condensed azo pigments, azo lakes, chelated azo pigments, phthalocyanine pigments, perylene and pyrene pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindolinone pigments, isoindolinone pigments, quinophthalone pigments, and other polycyclic pigments, dye chelates, dyeing lakes, nitro pigments, nitroso pigments, aniline black, daylight fluorescent pigments, carbon black, etc. One of these pigments can be used alone, or two or more can be used simultaneously. Furthermore, glossy pigments can also be used as colorants.

[0154] There are no particular limitations on the specific examples of pigments; for example, the following pigments can be cited.

[0155] Examples of white pigments include metal oxides, barium sulfate, and calcium carbonate. Examples of metal oxides include titanium dioxide, zinc oxide, silicon dioxide, aluminum oxide, and magnesium oxide. Additionally, white pigments can also be made from hollow particles; well-known types of hollow particles can be used.

[0156] Examples of black pigments include: No. 2300, No. 900, MCF88, No. 33, No. 40, No. 45, No. 52, MA7, MA8, MA100, and No. 2200B (all manufactured by Mitsubishi Chemical Corporation); Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, and Raven 700 (manufactured by Carbon Columbia); Rega1 400R, Rega1 330R, Rega1 660R, Mogul L, Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, and Monarch 1400 (Cabote Corporation, Japan). KK) made); Pigment FW1, Pigment FW2, Pigment FW2V, Pigment FW18, Pigment FW200, Pigment S150, Pigment S160, Pigment S170, Printex 35, Printex U, Printex V, Printex 140U, Special Black 6, Special Black 5, Special Black 4A, Special Black 4 (all made by Degussa).

[0157] Examples of yellow pigments include: CI Pigment Yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 37, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 153, 154, 167, 172, 180.

[0158] Examples of magenta pigments include: CI Pigment Red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48(Ca), 48(Mn), 57(Ca), 57:1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168, 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245, or CI Pigment Violet 19, 23, 32, 33, 36, 38, 43, 50.

[0159] Examples of cyan pigments include: CI Pigment Blue 1, 2, 3, 15, 15:1, 15:2, 15:3, 15:34, 15:4, 16, 18, 22, 25, 60, 65, 66; CI Vat Blue 4, 60.

[0160] In addition, there are no special restrictions on pigments other than magenta, cyan, and yellow. For example, CI pigments green 7 and 10; CI pigments brown 3, 5, 25, and 26; CI pigments orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, and 63.

[0161] As for pearlescent pigments, there are no particular limitations. Examples include titanium dioxide-coated mica, fish scale foil, and bismuth oxychloride, which are pigments with pearlescent or interference luster.

[0162] As a metallic pigment, there are no particular limitations; examples include particles composed of elements or alloys such as aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, and copper.

[0163] In addition, as dyes, various dyes commonly used in inkjet recording can be used, such as direct dyes, acid dyes, food dyes, basic dyes, reactive dyes, disperse dyes, vat dyes, soluble vat dyes, and reactive disperse dyes.

[0164] The content of the colorant relative to the total mass of the coloring ink composition is preferably 0.3% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 15% by mass or less. Further, it is preferably 1% by mass or more and 10% by mass or less, more preferably 2% by mass or more and 7% by mass or less.

[0165] When pigments are used in color materials, the volume average particle size of the pigment particles is preferably 10 nm or more and 300 nm or less, more preferably 30 nm or more and 250 nm or less, even more preferably 50 nm or more and 250 nm or less, and particularly preferably 70 nm or more and 200 nm or less. Further, it is preferably 80 nm or more and 150 nm or less. When the volume average particle size is within the above range, it is preferable in that the desired color material is easily obtained, and the properties of the color material are easily improved.

[0166] Furthermore, the volume average particle size of the colorant can be measured, for example, by a particle size distribution measuring device. Examples of such devices include particle size analyzers based on the dynamic light scattering method (e.g., the "Nanotrac series" manufactured by MicrotracBEL). The volume average particle size is set as the D50 value.

[0167] The pigment material is preferably able to be stably dispersed in the dispersion medium, so a dispersant can also be used to disperse it. Examples of dispersants include resin dispersants. In addition, the pigment material can be used to modify the surface of the pigment particles by oxidizing or sulfonating the pigment surface with substances such as ozone, hypochlorous acid, or fuming sulfuric acid, thereby using it as a self-dispersing pigment.

[0168] Examples of resin dispersants (dispersant resins) include: 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, and other (meth)acrylic acid resins and their salts; 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, styrene-maleic acid copolymer, styrene-maleic anhydride copolymer, and other styrene-based resins and their salts; polyurethane resins and their salts, which are polymeric compounds (resins) containing urethane bonds formed by the reaction of isocyanate groups and hydroxyl groups, and can be linear and / or branched, regardless of whether they have a cross-linked structure; polyvinyl alcohols; vinylnaphthalene-maleic acid copolymers and their salts; vinyl acetate-maleic acid copolymers and their salts; and vinyl acetate-crotonic acid copolymers and their salts, etc., which are water-soluble resins. Preferably, copolymers of monomers having hydrophobic functional groups and monomers having hydrophilic functional groups, or polymers composed of monomers having both hydrophobic and hydrophilic functional groups, are used. As the form of copolymer, any of the following can be used: random copolymer, block copolymer, alternating copolymer, or graft copolymer.

[0169] Commercially available dispersants for styrene-based resins include: X-200, X-1, X-205, X-220, X-228 (manufactured by Starlight PMC); Nopcosperse (registered trademark) 6100, 6110 (manufactured by SanNopco Co., Ltd.); 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.

[0170] In addition, commercially available dispersants for acrylic resins include: BYK-187, BYK-190, BYK-191, BYK-194N, BYK-199 (manufactured by BYK Chemie Co., Ltd.); Aron A-210, A6114, AS-1100, AS-1800, A-30SL, A-7250, CL-2 (manufactured by Toa Synthetic Co., Ltd.), etc.

[0171] Furthermore, commercially available dispersants for polyurethane resins include: BYK-182, BYK-183, BYK-184, BYK-185 (manufactured by BYK Chemie Co., Ltd.), TEGO Disperse 710 (manufactured by Evonic Tego Chemi Co., Ltd.), and Borchi (registered trademark) Gen1350 (manufactured by OMG Borschers Co., Ltd.).

[0172] The dispersant can be used alone or in combination with two or more. The total content of the dispersant relative to 100 parts by weight of the pigment is preferably 10 parts by weight or more and 90 parts by weight or less, more preferably 30 parts by weight or more and 80 parts by weight or less, and even more preferably 50 parts by weight or more and 70 parts by weight or less. When the content of the dispersant relative to 100 parts by weight of the pigment is within the above range, the reactivity with the processing liquid becomes better, tending to result in superior image quality and better adhesion and abrasion resistance.

[0173] In the dispersants exemplified above, at least one selected from anionic dispersant resins is more preferred. Furthermore, in this case, the weight-average molecular weight of the dispersant is more preferably 500 or more. Further, it is preferably 5000 or more and 100000 or less, more preferably 10000 or more and 50000 or less.

[0174] By using such a resin dispersant as a dispersant, the dispersion and aggregation of pigments are improved, resulting in better dispersion stability and higher image quality. Furthermore, it is preferable that the viscosity increase ratio (described later) of the coloring ink composition is easily achieved to a predetermined level (e.g., 5 times or more, preferably 10 times or more).

[0175] Anionic dispersant resins are resins that possess anionic functional groups and exhibit anionic properties. Examples of anionic functional groups include carboxyl groups, sulfonyl groups, and phosphate groups. Among these groups, carboxyl groups are more preferred.

[0176] The dispersant resin preferably has an acid value of 5 mg KOH / g or higher, more preferably 10 to 150 mg KOH / g, and even more preferably 15 to 100 mg KOH / g. Furthermore, an acid value of 20 to 80 mg KOH / g is preferred, and more preferably 25 to 50 mg KOH / g. In this case, it is preferable that the viscosity increase ratio (described later) of the coloring ink composition is at least a predetermined value (e.g., 5 times or more, preferably 10 times or more).

[0177] The acid value can be determined by neutralization potential difference titration according to JIS K0070. For example, the "AT610" manufactured by Kyoto Electronics Industry Co., Ltd. can be used as the titration apparatus.

[0178] resin

[0179] The coloring ink composition used in the recording method according to this embodiment may also contain resin particles, wax, or other resins. The type and content of the resin may be the same as those in the transparent ink composition described later.

[0180] surfactants

[0181] The coloring ink composition used in the recording method according to this embodiment may also contain a surfactant. The type and content of the surfactant can be the same as those of the processing liquid described above.

[0182] organic solvents

[0183] The coloring ink composition used in the recording method according to this embodiment may also contain organic solvents. The type and content of the organic solvents can be the same as those of the processing liquid described above.

[0184] water

[0185] The coloring ink composition used in the recording method according to this embodiment may also contain water. The type and content of water can be the same as those of the processing liquid described above.

[0186] Other ingredients

[0187] The coloring ink composition used in the recording method according to this embodiment may also contain various additives such as urea, amines, sugars, preservatives / mildew inhibitors, rust inhibitors, chelating agents, viscosity modifiers, and antioxidants.

[0188] physical properties

[0189] The surface tension and viscosity of the coloring ink composition used in the recording method described in this embodiment can be the same as those of the processing liquid described above.

[0190] Viscosity ratio

[0191] When the coloring ink composition is mixed with the above-mentioned treatment liquid at a mass ratio of 10:1, the viscosity increase ratio is preferably 5 times or more, more preferably 7 times or more, even more preferably 9 times or more, and particularly preferably 10 times or more. The upper limit of this viscosity increase ratio is preferably less than 20 times, more preferably less than 15 times, and even more preferably less than 13 times. When the viscosity increase ratio is within the above range, there is a tendency to obtain superior image quality and superior filling and abrasion resistance.

[0192] Here, the "viscosity increase ratio" in the coloring ink composition is defined as follows: Using the coloring ink composition and processing liquid used in the recording method, the coloring ink composition and processing liquid are mixed and stirred at a mass ratio of 10:1. The viscosity of the mixed liquid is the ratio (multiple) to the viscosity of the coloring ink composition before mixing. Viscosity is measured at 20°C. Therefore, the viscosity increase ratio is the ratio of the viscosity after mixing to the viscosity before mixing. Furthermore, depending on the composition of the processing liquid and ink, there may be cases where the viscosity increase rate is less than 1.0 times, resulting in a decrease in viscosity, but this is still referred to as the viscosity increase ratio. Viscosity can be measured using a rheometer.

[0193] The viscosity-increasing ratio in the coloring ink composition can be adjusted by modifying the type and content of the colorant (including resin dispersant), resin, etc. In particular, adjustments made by modifying the type and content of the colorant (including resin dispersant) are easy to make and are therefore preferred.

[0194] 1.4 Transparent Ink Adhesion Process

[0195] The recording method according to this embodiment includes a step of ejecting a transparent ink composition containing resin from an inkjet head and adhering it to a recording medium (transparent ink adhering step).

[0196] The preferred amount of the transparent ink composition is 0.5 mg / inch per unit area of ​​the recording medium. 2 More preferably 0.6 mg / inch 2 The above is further optimized to 0.7 mg / inch. 2The above is further optimized to 0.8 mg / inch. 2 The above is particularly preferred at 0.9 mg / inch. 2 The above is a preferred dosage of 1.0 mg / inch. 2 That's all. Additionally, the preferred upper limit is 5.0 mg / inch. 2 Below, 3.0 mg / inch is preferred. 2 Below, 2.0 mg / inch is further preferred. 2 The following is a preferred dosage: 1.5 mg / inch 2 The following applies. When the amount of the transparent ink composition applied is within the above-mentioned range, there is a tendency to obtain superior image quality and superior filling and abrasion resistance. Furthermore, the maximum amount of the transparent ink composition applied in the transparent ink application process can also be set within the above-mentioned range.

[0197] In the region where the aforementioned colored ink composition and transparent ink composition are adhered, and in the region where the amount of the colored ink composition is the highest, the total amount of the transparent ink composition adhered relative to the total amount of the colored ink composition is preferably 5% by mass or more and 70% by mass or less, more preferably 5% by mass or more and 60% by mass or less, further preferably 5% by mass or more and 50% by mass or less, even more preferably 5% by mass or more and 40% by mass or less, particularly preferably 5% by mass or more and 30% by mass or less, even more preferably 5% by mass or more and 20% by mass or less, and even more preferably 5% by mass or more and 15% by mass or less. This tends to result in superior image quality and superior embedding and abrasion resistance. In addition, the total amount of adhesion of the transparent ink composition may be the amount of adhesion from the area with the highest amount of adhesion of the colored ink composition to the area with the highest amount of adhesion of the transparent ink composition and the colored ink composition, or the amount of adhesion from the area with the highest amount of adhesion of the colored ink composition to the area with the highest amount of adhesion of the colored ink composition, or the amount of adhesion from the area with the highest amount of adhesion of the colored ink composition, or the amount of adhesion from the area with the highest amount of adhesion of the colored ink composition, or the amount of adhesion from the area with the highest amount of adhesion of the colored ink composition.

[0198] Transparent ink composition

[0199] The components contained in the transparent ink composition used in the recording method according to this embodiment will be described below. Furthermore, the transparent ink composition is not a coloring ink composition used to color the recording medium, but rather a coating liquid used in conjunction with a coloring ink composition. Additionally, the transparent ink composition may contain pigments or other coloring materials, but the content relative to the total mass of the transparent ink composition is preferably 0.2% by mass or less, more preferably 0.1% by mass or less, even more preferably 0.05% by mass or less, and the lower limit is 0% by mass. The transparent ink composition preferably does not contain any coloring materials.

[0200] resin

[0201] The transparent ink composition used in the recording method according to this embodiment contains a resin. Examples of resins include resin particles that improve the adhesion and abrasion resistance of the ink components and function as a so-called fixing resin, and waxes that can improve abrasion resistance by imparting lubrication to the formed image.

[0202] resin particles

[0203] Examples of resin particles include those composed of, for example, polyurethane-based resins, acrylic resins (including styrene-acrylic resins), fluorene-based resins, polyolefin-based resins, rosin-modified resins, terpene-based resins, polyester-based resins, polyamide-based resins, epoxy resins, vinyl chloride-based resins, vinyl chloride-vinyl acetate copolymers, and ethylene-vinyl acetate-based resins. Polyurethane-based resins, acrylic resins, polyolefin resins, and polyester resins are preferred. These resin particles are mostly processed in emulsion form, but can also be in powder form. Furthermore, resin particles can be used alone or in combination of two or more.

[0204] Polyurethane resins refer to a general term for resins containing urethane bonds. Polyurethane resins can include polyether-type polyurethane resins (whose main chain contains ether bonds in addition to urethane bonds), polyester-type polyurethane resins (whose main chain contains ester bonds in addition to urethane bonds), and polycarbonate-type polyurethane resins (whose main chain contains carbonate bonds in addition to urethane bonds), etc. In addition, commercially available products can be used as polyurethane resins, such as SUPERFLEX460, 460s, 840, E-4000 (trade name, manufactured by Daiichi Kogyo Pharmaceutical Co., Ltd.), Resamine D-1060, D-2020, D-4080, D-4200, D-6300, D-6455 (trade name, manufactured by Daiichi Seika Kogyo Co., Ltd.), TakelacWS-6021, W-512-A-6 (trade name, manufactured by Mitsui Chemicals Polyurethane Co., Ltd.), SunCure2710 (trade name, manufactured by LUBRIZOL Co., Ltd.), and PermarinUA-150 (trade name, manufactured by Sanyo Chemical Co., Ltd.).

[0205] 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 obtained from acrylic monomers, or copolymers of acrylic monomers with monomers other than those monomers. For example, acrylic-vinyl resins, which are copolymers of acrylic monomers and vinyl monomers, are examples. Additionally, styrene is an example of a vinyl monomer.

[0206] Acrylamide and acrylonitrile can also be used as acrylic monomers. For 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.), Mowinyl 952B, 718A (trade name, manufactured by Nippon Synthetic Chemical Co., Ltd.), Nipol LX 852, and LX 874 (trade name, manufactured by Nippon Zeon Co., Ltd.).

[0207] Furthermore, in this specification, the acrylic resin may also be the styrene-acrylic resin described later. Additionally, in this specification, the expression "(meth)propenyl" means propenyl or methpropenyl.

[0208] Styrene-acrylic resins are copolymers obtained from styrene monomers and (meth)acrylic monomers, such as 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. For styrene-acrylic resins, commercially available products can be used, such as Joncryl 62J, 7100, 390, 711, 511, 7001, 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 name, manufactured by BASF), Mowinyl 966A, 975N (trade name, manufactured by Nippon Synthetic Chemicals Co., Ltd.), Vinyblan2586 (manufactured by Nissin Chemical Co., Ltd.), etc.

[0209] Polyolefin resins are resins that contain olefins such as ethylene, propylene, and butene in their structural backbone. Well-known polyolefin resins can be appropriately selected for use. As olefin resins, commercially available products can be used, such as ArrowBaseCB-1200 and CD-1200 (trade name, manufactured by Unitika Co., Ltd.).

[0210] In addition, resin particles can be supplied in the form of an emulsion. Examples of commercially available resin emulsions include the following: Microgel E-1002, E-5002 (trade name of PAINT Corporation, Japan, styrene-acrylic resin emulsion); Voncoat4001 (trade name of DIC Corporation, acrylic resin emulsion); Voncoat5454 (trade name of DIC Corporation, styrene-acrylic resin emulsion); Polysol AM-710, AM-920, AM-2300, AP-4735, AT-860, PSASE-4210E (acrylic resin emulsion); Polysol AP-7020 (styrene-acrylic resin emulsion); Polysol SH-502 (vinyl acetate resin emulsion); Polysol AD-13, AD-2, AD-10, AD-96, AD-17, AD-70 (ethylene-vinyl acetate resin emulsion); Polysol PSASE-6010 (Ethylene-Vinyl Acetate Resin Emulsion) (trade name manufactured by Showa Denko Corporation); Polysol SAE1014 (trade name, styrene-acrylic resin emulsion, manufactured by Zeon Corporation of Japan), Saivinol SK-200 (trade name, acrylic resin emulsion, manufactured by Saiden Chemical Co., Ltd.), AE-120A (trade name manufactured by JSR Corporation, acrylic resin emulsion), AE373D (trade name manufactured by E-TEC Corporation, carboxyl-modified styrene-acrylic resin emulsion), Seikadyne1900W (trade name manufactured by Daihisei Chemical Industry Co., Ltd., ethylene-vinyl acetate resin emulsion), Vinyblan2682 (acrylic resin emulsion), Vinyblan2886 (vinyl acetate-acrylic resin emulsion), Vinyblan5202 (acrylic acetate-acrylic resin emulsion) (trade name manufactured by Nissin Chemical Industry Co., Ltd.); Elitel KA-5071S, KT-8803, KT-9204, KT-8701, KT-8904, KT-0507 (Unitika, trade name, polyester resin emulsion); HYTEC SN-2002 (Toho Chemical, trade name, polyester resin emulsion); Takelac W-6020, W-635, W-6061, W-605, W-635, W-6021 (Mitsui Chemicals Polyurethane, trade name, polyurethane resin emulsion); Superflex 870, 800, 150, 420, 460, 470, 610, 700 (Daiichi Kogyo Pharmaceutical, trade name, polyurethane resin emulsion); Permarin UA-150 (Sanyo Chemicals, Ltd., polyurethane resin emulsion); Sancure 2710 (Lubrizol, Japan, polyurethane resin emulsion).NeoRez R-9660, R-9637, R-940 (manufactured by Kusumoto Chemical Co., Ltd., polyurethane resin emulsions); Adeka BonTighter HUX-380, 290K (manufactured by ADEKA Co., Ltd., polyurethane resin emulsions); Movinyl 966A, Mowinyl 7320 (manufactured by Nippon Synthetic Chemicals Co., Ltd.); Joncryl 7100, 390, 711, 511, 7001, 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 (all manufactured by BASF); NKBinder R-5HN (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.); Hydran WLS-210 (non-crosslinked polyurethane: manufactured by DIC Corporation); Joncryl 7610 (manufactured by BASF), etc.

[0211] 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, 50°C or higher and 80°C or lower is particularly preferred. By keeping the glass transition temperature (Tg) of the resin particles within the above range, they tend to exhibit superior abrasion resistance. The glass transition temperature is measured, for example, using a differential scanning calorimeter "DSC7000" manufactured by Hitachi High-Tech Science Co., Ltd., according to JIS K7121 (Method for Determination of Transition Temperature of Plastics).

[0212] 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.

[0213] The acid value of the resin in the resin particles is preferably 70 mg KOH / g or less, more preferably 60 mg KOH / g or less, even more preferably 50 mg KOH / g or less, and particularly preferably 30 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, it is preferable to easily achieve a viscosity increase ratio (described later) of at least a predetermined value (e.g., 5 times or more, preferably 10 times or more, more preferably 15 times or more). The acid value can be determined by the method described above.

[0214] When the transparent ink composition contains resin particles, the content of these particles relative to the total mass of the transparent ink composition, calculated as solids, is 1% or more and 20% or less, preferably 3% or more and 15% or less, and more preferably 5% or more and 10% or less.

[0215] wax

[0216] As components of waxes, various types can be used alone or in combination, such as plant / animal waxes like carnauba wax, candelilla wax, beeswax, rice bran wax, and lanolin; petroleum-based waxes like paraffin wax, microcrystalline wax, polyethylene wax, oxidized polyethylene wax, and petrolatum; mineral-based waxes like lignite wax and ceresin wax; synthetic waxes like carbon wax, Hoechst wax, polyolefin wax, and stearamide; and natural / synthetic wax emulsions or composite waxes like α-olefin-maleic anhydride copolymers. From the viewpoint of superior abrasion resistance, polyolefin waxes (especially polyethylene wax and polypropylene wax) and paraffin wax are preferred.

[0217] As a wax, commercially available products can also be used directly, such as NopcotePEM-17 (trade name, manufactured by SanNopco Co., Ltd.), ChemipearlW4005 (trade name, manufactured by Mitsui Chemicals Co., Ltd.), AQUACER515, 539, 593 (all of the above are trade names, manufactured by BYK Chemie Japan Co., Ltd.), etc.

[0218] Furthermore, when the recording method includes a heating process, from the viewpoint of preventing the wax from melting excessively and reducing its performance, it is preferable to use a wax with a melting point of 50°C or higher and 200°C or lower, more preferably a melting point of 70°C or higher and 180°C or lower, and even more preferably a melting point of 90°C or higher and 150°C or lower.

[0219] The wax can also be supplied in the form of an emulsion or suspension. The wax content, calculated as solids relative to the total mass of the transparent ink composition, is 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 5% by mass or less, and even more preferably 0.5% by mass or more and 2% by mass or less. When the wax content is within the above range, it tends to effectively perform the functions of the wax.

[0220] surfactants

[0221] The transparent ink composition used in the recording method according to this embodiment may contain a surfactant. The type and content of the surfactant may be the same as those of the treatment liquid described above.

[0222] organic solvents

[0223] The transparent ink composition used in the recording method according to this embodiment may contain an organic solvent. The type and content of the organic solvent may be the same as those of the processing liquid described above.

[0224] water

[0225] The transparent ink composition used in the recording method according to this embodiment may contain water. The type and content of water may be the same as those of the processing liquid described above.

[0226] Other ingredients

[0227] The transparent ink composition used in the recording method described in this embodiment may also contain various additives such as urea, amines, sugars, preservatives / mildew inhibitors, rust inhibitors, chelating agents, viscosity modifiers, and antioxidants.

[0228] physical properties

[0229] The surface tension and viscosity of the coloring ink composition used in the recording method described in this embodiment can be the same as those of the processing liquid described above.

[0230] Viscosity ratio

[0231] The viscosity increase ratio of the transparent ink composition when mixed with the processing liquid at a mass ratio of 10:1 is preferably higher than that of the colored ink composition when mixed with the processing liquid at a mass ratio of 10:1, more preferably 1.2 times or more, even more preferably 1.3 times or more, and particularly preferably 1.5 times or more. This results in better suppression of the reaction between the colored ink composition and the processing liquid, and better image filling. Furthermore, the upper limit is preferably 3 times or less, more preferably 2.5 times or less, and even more preferably 2.0 times or less. This allows the colored ink composition to react sufficiently with the processing liquid and suppresses coarse particle formation of the ink components, thus resulting in better image quality and abrasion resistance.

[0232] The viscosity increase ratio of the transparent ink composition when mixed with the aforementioned processing liquid at a mass ratio of 10:1 is preferably 5 times or more, more preferably more than 5 times, more preferably more than 7 times, further preferably more than 10 times, particularly preferably more than 12 times, and even more particularly preferably more than 15 times. This results in better suppression of the reaction between the colored ink composition and the processing liquid, and better image filling. Furthermore, the upper limit of this viscosity increase ratio is preferably 25 times or less, more preferably 20 times or less, and even more preferably 15 times or less. This allows the colored ink composition to react sufficiently with the processing liquid and suppresses the coarse particle formation of the ink components, thus resulting in better image quality and abrasion resistance.

[0233] Furthermore, the "viscosity ratio" in the transparent ink composition is defined in the same way as that in the colored ink composition described above.

[0234] The viscosity-increasing ratio in the transparent ink composition can be adjusted by changing the type and content of the resin, etc. In particular, adjustments made by changing the type and content of the resin particle emulsion are easy to make and are therefore preferred.

[0235] 1.5 Single Drying Process

[0236] The recording method according to this embodiment may include a primary drying step for drying the recording medium before or simultaneously with the aforementioned processing liquid adhesion step, color ink adhesion step, and transparent ink adhesion step. The primary drying step can be performed not only by stopping recording and placing the medium, but also by using a drying mechanism. Examples of methods for drying using a drying mechanism include methods that supply air at room temperature or warm air to the recording medium (air-flow type), methods that irradiate the recording medium with radiation (infrared rays, etc.) to generate heat (radiation type), methods that transfer heat to the recording medium through contact (conduction type), and combinations of two or more of these methods. In the case of a drying step, the air-flow type is more preferred.

[0237] The use of a drying mechanism that heats the recording medium as a drying unit in a primary drying process is specifically referred to as a heating process (primary heating process). For example, a drying process using room temperature air supply in the aforementioned drying mechanism does not constitute a heating process.

[0238] The surface temperature of the recording medium in the primary drying step is preferably set to the surface temperature of the recording medium in the aforementioned color ink adhesion step. This offers advantages for landfill applications. Furthermore, the primary drying step preferably does not involve a primary heating step.

[0239] 1.6 Secondary drying process

[0240] The recording method described in this embodiment includes a secondary drying step that further heats the recording medium after the aforementioned processing liquid adhesion step, color ink adhesion step, and transparent ink adhesion step. The secondary drying step can be performed using, for example, a suitable heating method. The secondary drying step is performed using, for example, a post-heater (in the example of the inkjet recording apparatus described later, equivalent to heating heater 5). Furthermore, the heating method is not limited to the heating method provided by the inkjet recording apparatus; other drying methods can also be used. This allows the obtained image to dry more thoroughly, thus enabling the recorded material to be used sooner.

[0241] In this case, the temperature of the recording medium is not particularly limited, and can be set based on factors such as the Tg of the resin particles and wax. In this case, it can be set to be 5.0°C or more higher than the Tg of the resin components constituting the resin particles and wax, and preferably 10.0°C or more higher.

[0242] The surface temperature of the recording medium reached by the heating in the secondary drying process is 30.0°C or higher and 120.0°C or lower, preferably 40.0°C or higher and 100.0°C or lower, more preferably 50.0°C or higher and 90°C or lower, and even more preferably 60°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 achieve the following: the resin particles and wax contained in the recording can be film-formed and planarized, and the resulting image can be dried more thoroughly and fixed.

[0243] 2. Recording device

[0244] One embodiment of the present invention relates to a recording apparatus that records using the above-described recording method, and includes the above-described coloring ink composition, transparent ink composition, and inkjet head.

[0245] According to the recording apparatus of this embodiment, since recording is performed by the above-described recording method, excellent image quality, as well as excellent caking and abrasion resistance, can be obtained.

[0246] Hereinafter, an example of the recording device according to this embodiment will be described with reference to the accompanying drawings.

[0247] 2.1 Serial inkjet recording device

[0248] Figure 1 This is a schematic cross-sectional view of the inkjet recording device 1. Figure 2 It is shown Figure 1 A perspective view of an example of the structure surrounding the carriage of the inkjet recording device 1. Figure 1 , 2 As shown, the inkjet recording device 1 includes an inkjet head 2, an IR heater 3, a pressure plate heater 4, a heating heater 5, a cooling fan 6, a preheater 7, a ventilation fan 8, a carriage 9, a pressure plate 11, a carriage moving mechanism 13, a transport unit 14, and a control unit CONT. The inkjet recording device 1... Figure 2 The control unit CONT shown controls the overall operation of the inkjet recording device 1.

[0249] The inkjet head 2 is a structure that records the recording medium M by ejecting a coloring ink composition and a transparent ink composition (hereinafter also referred to as "ink, etc.") from the nozzle of the inkjet head 2 and allowing them to adhere. Alternatively, it can be configured to eject a processing liquid from the nozzle of the inkjet head 2 and allow it to adhere to the recording medium M. In this embodiment, the inkjet head 2 is a serial inkjet head that performs multiple scans relative to the recording medium M in the main scanning direction to allow the ink to adhere to the recording medium M. The inkjet head 2 is mounted on... Figure 2 The carriage 9 is shown. The inkjet head 2 performs multiple scans relative to the recording medium M in the main scanning direction by means of the carriage moving mechanism 13, which moves the carriage 9 in the media width direction of the recording medium M. The media width direction refers to the main scanning direction of the inkjet head 2. Scanning in the main scanning direction is also called main scanning.

[0250] Furthermore, here, the main scanning direction is the direction of movement of the carriage 9, which carries the inkjet head 2. Figure 1 In the middle, it is the direction that intersects with the sub-scanning direction, which is the transport direction of the recording medium M, as indicated by arrow SS. Figure 2 In this process, the width direction of the recording medium M, i.e., the direction represented by S1-S2, is the main scanning direction MS, and the direction represented by T1→T2 is the secondary scanning direction SS. Furthermore, in a single scan, scanning is performed in the main scanning direction, i.e., in either direction of arrow S1 or arrow S2. Recording of the recording medium M is achieved by repeatedly performing the main scan of the inkjet head 2 and the secondary scans that transport the recording medium M. That is, the color ink application process, the transparent ink application process, and the required processing liquid application process are performed through multiple main scans in which the inkjet head 2 moves in the main scanning direction and multiple secondary scans in which the recording medium M moves in the secondary scanning direction intersecting the main scanning direction.

[0251] The ink cartridge 12, which supplies inks or processing liquids to the inkjet head 2, comprises multiple independent cartridges. The ink cartridge 12 is detachably mounted on the carriage 9 on which the inkjet head 2 is mounted. Different types of inks or processing liquids can be filled into each of the multiple cartridges, and inks or processing liquids are supplied from the ink cartridge 12 to each nozzle. Furthermore, in this embodiment, an example of the ink cartridge 12 being mounted on the carriage 9 is shown, but this is not a limitation; it may also be located outside the carriage 9 and supplied to each nozzle via a supply pipe (not shown).

[0252] The ejection from the inkjet head 2 can be performed using conventionally known methods. In this embodiment, a method of ejecting droplets by utilizing the vibration of a piezoelectric element, that is, an ejection method that forms ink droplets by the mechanical deformation of an electrostrictive element, is used.

[0253] The inkjet recording apparatus 1 includes a ventilation fan 8, an IR heater 3, and a pressure plate heater 4 for drying ink ejected from the inkjet head 2 and adhering to the recording medium M. A single drying process can be performed by appropriately combining these ventilation fan 8, IR heater 3, and pressure plate heater 4. In this single drying process, it is not necessary to heat the recording medium M; the ventilation fan 8 can also be used alone to provide airflow at room temperature.

[0254] Furthermore, if an IR heater 3 is used, the recording medium M can be radially heated from the inkjet head 2 side by infrared radiation. Thus, the inkjet head 2 can also be easily heated simultaneously, but compared to heating from the back of the recording medium M, such as from the pressure plate heater 4, the temperature rise is unaffected by the thickness of the recording medium M. Additionally, various fans (e.g., ventilation fan 8) can be provided to blow warm air or air at the same temperature as the ambient environment onto the recording medium M to dry the ink and other substances on the recording medium M.

[0255] The pressure plate heater 4 heats the recording medium M via the pressure plate 11 at a position opposite to the inkjet head 2, so that the ink ejected from the inkjet head 2 can dry as early as possible from the moment it adheres to the recording medium M. The pressure plate heater 4 can heat the recording medium M by conduction, allowing ink to adhere to the heated recording medium M.

[0256] Furthermore, the upper limit of the surface temperature of the recording medium M, heated by the IR heater 3 and the pressure plate heater 4, is preferably 50°C or less, more preferably 45°C or less. Further, it is preferably 40°C or less, more preferably 35°C or less, even more preferably 30°C or less, and particularly preferably 28°C or less. Additionally, the lower limit of the surface temperature of the recording medium M is preferably 25°C or more.

[0257] The heating heater 5 is used to dry and cure the ink or other substances adhered to the recording medium M, that is, for secondary heating or secondary drying. The heating heater 5 can be used in the secondary drying process. The heating heater 5 heats the recording medium M on which the image is recorded, thereby causing the moisture and other substances contained in the ink or other substances to evaporate more rapidly, and forming an ink film by the resin contained in the transparent ink composition. In this way, the ink film is firmly fixed or adhered to the recording medium M, resulting in excellent film-forming properties and enabling the acquisition of excellent high-quality images in a short time.

[0258] The upper limit of the surface temperature of the recording medium M, which is heated by the heating heater 5, 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 the above range, there is a tendency to obtain high-quality images in a short time.

[0259] The inkjet recording device 1 may include a cooling fan 6. After the ink or the like recorded on the recording medium M is dried, the cooling fan 6 cools the ink or the like on the recording medium M, thereby enabling the formation of an ink coating film with good adhesion on the recording medium M.

[0260] Additionally, the inkjet recording apparatus 1 may also include a preheater 7 that preheats the recording medium M before the ink or the like adheres to it. Furthermore, the inkjet recording apparatus 1 may also include a ventilation fan 8 to dry the ink or the like adhering to the recording medium M more efficiently.

[0261] Below the carriage 9 are: a pressure plate 11 supporting the recording medium M, a carriage moving mechanism 13 for moving the carriage 9 relative to the recording medium M, and a roller, i.e., a transport unit 14, for transporting the recording medium M in the sub-scanning direction. The operation of the carriage moving mechanism 13 and the transport unit 14 is controlled by the control unit CONT.

[0262] 2.2 Inkjet recording device with lateral scanning method

[0263] Figure 3 This is a schematic side view of an inkjet recording device 300 that records by means of lateral scanning. Figure 4 This is a schematic top-view view of an inkjet recording apparatus 300 that records using a transverse scanning method. The inkjet recording apparatus 300 includes: a carriage moving mechanism 310, including a sub-scanning axis carriage moving mechanism 312 and a main scanning axis carriage moving mechanism 311; a carriage 320, including an inkjet head 2 (not shown) that can be configured with the same structure as the inkjet recording apparatus 1 described above; and a transport roller 330 for transporting the recording medium M. Alternatively, a transport roller (not shown) may be included to move the recording medium M in the sub-scanning direction SS.

[0264] The carriage moving mechanism 310 allows the carriage 320, which includes the inkjet head 2 (not shown), to move freely in the main scanning direction MS, which corresponds to the transport direction of the recording medium M, and the sub-scanning direction SS, which corresponds to the direction orthogonal to the transport direction of the recording medium M. The carriage moving mechanism 310 consists of a main scanning axis carriage moving mechanism 311 that moves the carriage 320 in the main scanning direction MS, a sub-scanning axis carriage moving mechanism 312 that moves the main scanning axis carriage moving mechanism 311 in the sub-scanning direction SS, and a motor (not shown) that moves them.

[0265] The carriage 320 is mounted on the main scanning axis carriage moving mechanism 311. When the main scanning axis carriage moving mechanism 311 moves in the main scanning direction MS, the carriage 320 also moves in the main scanning direction MS. Similarly, when the sub-scanning axis carriage moving mechanism 312 moves in the sub-scanning direction SS, the carriage 320 also moves in the sub-scanning direction SS. Furthermore, by moving the carriage 320 in both the main scanning direction MS and the sub-scanning direction SS, the carriage 320 can move in a direction inclined relative to the main scanning direction MS.

[0266] In this way, a main scan can be performed multiple times, moving the carriage 320 containing the inkjet head 2 or the recording medium M in the main scanning direction MS, and printing an image on the recording medium M in the printing area. Afterwards, a sub-scan can be performed, moving the recording medium M or the carriage 320 in the sub-scanning direction SS, which intersects the main scanning direction. Furthermore, by alternately repeating the action of printing an image on the recording medium M supplied to the printing area (image forming action) and the action of partially supplying a new recording medium M to the printing area via the transport roller 330 in the transport direction (transport action), multiple images can be printed on the recording medium M.

[0267] Although not shown, the inkjet recording device 300 may also include an IR heater 3, a pressure plate heater 4, a heating heater 5, a cooling fan 6, a preheater 7, a ventilation fan 8, a pressure plate 11, and a control unit CONT, and can be configured with the same structure as the inkjet recording device 1 described above.

[0268] 3. Example

[0269] The present invention will be described in more detail below through examples, but the present invention is not limited to these examples. Unless otherwise specified, all percentages (%) are mass measurements.

[0270] 3.1 Preparation of the treatment liquid, the coloring ink composition, and the transparent ink composition

[0271] The components were placed in a container as shown in Table 1, and mixed and stirred with a magnetic stirrer for 2 hours. The mixture was then further dispersed using a bead mill filled with 0.3 mm diameter zirconia beads to ensure thorough mixing. After stirring for 1 hour, the mixture was filtered using a 5.0 μm PTFE membrane filter to obtain the treatment liquid (R1), transparent ink compositions (CL1–CL3), and colored ink compositions (Col1). The values ​​related to each component in Table 1 represent mass percent. Pure water was used and added at 100% by mass of the total mass of each composition. For the colorant and dispersion resin, a colorant dispersion was prepared as follows and used.

[0272] First, 12 parts by mass of anionic acrylic-acrylate copolymer (weight average molecular weight: 25,000, acid value: 35) were added to 155 parts by mass of ion-exchanged water after dissolving 0.1 parts by mass of a 30% ammonia solution (neutralizing agent) as a resin dispersant (resin C) and dissolved. Then, 18 parts by mass of carbon black as a black pigment were added, and the mixture was dispersed for 10 hours using a zirconia bead-based ball mill. Next, the mixture was centrifuged and filtered to remove coarse particles and impurities, and the carbon black concentration was adjusted to 20% by mass to obtain a pigment dispersion. The black pigment had an average particle size of 60 nm.

[0273] Table 1

[0274]

[0275] Supplementary explanations are provided for the information recorded in Table 1.

[0276] • Dispersion resin, Resin C (anionic): Acrylic acid-acrylate copolymer (weight average molecular weight: 25,000, acid value: 35)

[0277] • Carbon black: No. 33 (manufactured by Mitsubishi Chemical Corporation)

[0278] • Resin particles: Styrene-acrylic A: Refer to the following (highly cohesive resin particles)

[0279] • Resin particles: Styrene-acrylic B: Refer to the following (resin particles with low cohesion)

[0280] • Resin particles: Styrene-acrylic C: Refer to the following (resin particles with higher cohesiveness)

[0281] • Wax: Polyethylene type: "NopcoatPEM-17" (trade name, manufactured by SanNopco Co., Ltd.)

[0282] Surfactant: Organosilicon surfactant "BYK348" manufactured by BYK Corporation

[0283] (Resin particles: Preparation of styrene-acrylic B-based resin)

[0284] Resin emulsion B (acid value 7 mg KOH / g) was obtained by emulsion copolymerization of 75 parts by mass of styrene, 0.8 parts by mass of acrylic acid, 14.2 parts by mass of methyl methacrylate, and 10 parts by mass of cyclohexyl methacrylate. Furthermore, Newcol NT-30 (manufactured by Nippon Emulsifier Co., Ltd.) was used as a surfactant for emulsion polymerization, and its amount was set to 2 parts by mass relative to 100 parts by mass of the total monomers.

[0285] Resin Particles: Preparation of Styrene-Acrylic A

[0286] Except for changing the monomer composition, the same procedure was performed as described above to obtain resin emulsion A (acid value 30 mg KOH / g). The surfactant used in emulsion polymerization was defined as 1 part by mass relative to 100 parts by mass of the total monomer.

[0287] Resin Particles: Preparation of Styrene-Acrylic C

[0288] Except for changing the monomer composition, the same procedure was performed as described above to obtain resin emulsion C (acid value 50 mg KOH / g). The surfactant used in emulsion polymerization was defined as 1 part by mass relative to 100 parts by mass of the total monomer.

[0289] The "viscosity increase ratio when mixed with the test solution under the same conditions as R1" listed in Table 1 is calculated by mixing each transparent ink composition (CL1~CL3) or colored ink composition (Col1) with the test solution under the same conditions as the treatment solution (R1) at a mass ratio of 10:1 and stirring for 1 minute. The mixture is then tested using a rheometer (MCR302 / Anton Paar) at 25°C and a shear rate of 200 s. -1 The viscosity ratio of the mixed liquid to the original ink viscosity was determined under the specified conditions.

[0290] 3.2 Record the experiment

[0291] Fill the modified SC-R5050 inkjet printer (manufactured by Seiko Epson Corporation) with various color ink compositions, various transparent ink compositions and various processing solutions.

[0292] Records were made according to the conditions described in Tables 2-3, and the records involved in each embodiment and comparative example were obtained.

[0293] In Examples 1-6, the processing liquid and coloring ink composition were simultaneously applied in the first stroke at the amounts shown in Table 2, and in the second stroke, the processing liquid, coloring ink composition, and transparent ink composition were simultaneously applied at the amounts shown in Table 2. In Example 7, the processing liquid and coloring ink composition were simultaneously applied in the first and second strokes at the amounts shown in Table 2, and in the third stroke, the processing liquid, coloring ink composition, and transparent ink composition were simultaneously applied at the amounts shown in Table 2. In Example 8, the processing liquid and coloring ink composition were simultaneously applied in the first stroke at the amounts shown in Table 2, and in the second stroke, the coloring ink composition and transparent ink composition were simultaneously applied at the amounts shown in Table 2. In Example 9, the processing liquid, coloring ink composition, and transparent ink composition were simultaneously applied in the first and second strokes at the amounts shown in Table 2.

[0294] In Comparative Example 1, the processing liquid and the coloring ink composition were simultaneously applied in the first and second strokes at the amounts shown in Table 3, while only the transparent ink composition was applied in the second stroke at the amounts shown in Table 3. In Comparative Examples 2-4, the processing liquid, the coloring ink composition, and the transparent ink composition were simultaneously applied in the first and second strokes at the amounts shown in Table 3. In Comparative Examples 5 and 6, only the coloring ink composition was applied in the first stroke at the amounts shown in Table 3, while both the coloring ink composition and the transparent ink composition were applied simultaneously in the second stroke at the amounts shown in Table 3. In Comparative Example 7, the processing liquid, the coloring ink composition, and the transparent ink composition were simultaneously applied in the first stroke at the amounts shown in Table 3, and this was recorded. In Comparative Example 8, the processing liquid and the coloring ink composition were simultaneously applied in the first and second strokes at the amounts shown in Table 3.

[0295] The recording resolution was based on 1200×1200 dpi, and the number of droplets per pixel was adjusted to achieve the adhesion amounts shown in Tables 2 and 3. The weight of the processed droplets was 3.2 ng / dot, the weight of the colored ink droplets was 4.6 ng / dot, and the weight of the transparent ink droplets was 4.6 ng / dot. Secondary heating was performed using a secondary heater downstream of the recording medium in the transport direction to heat the medium to 70°C. The recording medium used was PET50A (manufactured by Lintec).

[0296] 3.3 Evaluation Methods

[0297] 3.3.1 Abrasion resistance

[0298] Using the recording media obtained above, abrasion resistance was evaluated according to the following criteria. The recording medium used was GIY43R5 (transparent vinyl chloride manufactured by Lintec Sign System), and the secondary drying was performed at 70°C for 10 minutes.

[0299] benchmark

[0300] AA: No peeling occurred after 10 rubs with a load of 500g in the vibration and abrasion resistance test.

[0301] A: Peeling occurred after 10 rubs with a 500g load in the vibration abrasion resistance test, but it was less than 10% of the evaluated area.

[0302] B: In the vibration and abrasion resistance test, after 10 rubs with a 500g load, the peeling occurred at a rate of more than 10% but less than 20% relative to the evaluation area.

[0303] C: In the vibration and abrasion resistance test, after 10 rubs with a load of 500g, the peeling occurred by more than 20% relative to the evaluation area.

[0304] 3.3.2 Landfill

[0305] The full-page image area of ​​the above-obtained record was visually observed under fluorescent light and evaluated according to the following criteria.

[0306] benchmark

[0307] A: There are no unfilled areas or pinholes.

[0308] B: You can see some unfilled areas and pinholes.

[0309] C: The unfilled areas and pinholes are clearly visible.

[0310] 3.3.3 Image Quality

[0311] The full-page image area of ​​the recorded material obtained above was visually observed under fluorescent light and evaluated according to the following criteria. Furthermore, the image quality referred to here refers to image quality involving so-called uneven agglomeration or uneven bleeding. Ink droplets aggregate on the medium to form spots, and are affected by the agglomeration of the ink droplets. This depends on the degree of reaction and drying.

[0312] benchmark

[0313] A: There was no cohesion.

[0314] B: Some cohesion is evident.

[0315] C: Visible condensation

[0316] 3.3.4 Ejection Stability

[0317] Under the conditions described in the above recording test, image recording was performed continuously for 1 hour, and the nozzles of the nozzle assembly of the colored ink composition after recording were inspected. The total number of non-ejecting nozzles was divided by the total number of nozzles, and the results were evaluated according to the following criteria.

[0318] benchmark

[0319] A: The percentage of nozzles that do not spray is less than 1.0%.

[0320] B: No more than 1.0% of the nozzle does not spray and is below 2.0%.

[0321] C: No more than 2.0% of the nozzle does not spray out and is below 5.0%.

[0322]

[0323]

[0324] 3.4 Evaluation Results

[0325] The evaluation results are shown in Tables 2 and 3.

[0326] According to the various embodiments, excellent image quality, as well as excellent embedding and abrasion resistance, are obtained. These embodiments are recording methods for recording on a recording medium, wherein recording is performed by multiple scans. During the scans, ink is ejected from the inkjet head and adhered to the recording medium while the relative position of the inkjet head and the recording medium are moved. The recording method includes the following steps: a step of adhering a treatment liquid containing a coagulant to the recording medium; a step of ejecting a coloring ink composition containing a colorant from the inkjet head and adhering it to the recording medium; and a step of ejecting a transparent ink composition containing a resin from the inkjet head and adhering it to the recording medium. The adhering of the coloring ink composition is performed by scanning the same scanning area twice or more. In the final scan of the two or more scans, the amount of transparent ink composition adhering to the recording medium in the scanning area where the coloring ink composition is adhering is applied by the same scan is 80% or more by mass of the total amount of transparent ink composition adhering to the area in the final scan.

[0327] In contrast, in the comparative examples that are not like this, at least one of the following is worse: image quality, fill power, and abrasion resistance.

[0328] The following content is derived from the above implementation method.

[0329] One approach to recording methods is as follows:

[0330] A recording method, wherein recording is performed on a recording medium, wherein,

[0331] Recording is performed by multiple scans, during which the relative position of the inkjet head and the recording medium is moved while ink is ejected from the inkjet head and adhered to the recording medium.

[0332] The recording method includes the following steps:

[0333] The process of applying a treatment liquid containing a coagulant to the recording medium;

[0334] The process of ejecting a coloring ink composition containing a colorant from the inkjet head and adhering it to the recording medium; and

[0335] The process of ejecting a resin-containing transparent ink composition from the inkjet head and adhering it to the recording medium.

[0336] The coloring ink composition is adhered by performing the scan on the same scanning area more than twice.

[0337] In the final scan of the two or more scans, the transparent ink composition is applied to the scanned area of ​​the recording medium where the colored ink composition is applied, using the same scan.

[0338] The amount of the transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached is more than 80% by mass of the total amount of the transparent ink composition attached in that area.

[0339] In one embodiment of the above recording method, the viscosity increase ratio of the transparent ink composition when the transparent ink composition and the treatment liquid are mixed at a mass ratio of 10:1 may be higher than that of the colored ink composition when the colored ink composition and the treatment liquid are mixed at a mass ratio of 10:1.

[0340] In any of the above-described recording methods, in the region where the colored ink composition and the transparent ink composition are attached, the region with the highest amount of the colored ink composition attached, the total amount of the transparent ink composition attached is 5% by mass or more and 70% by mass or less relative to the total amount of the colored ink composition attached.

[0341] In any of the above recording methods, the surface temperature of the recording medium in the process of adhering the coloring ink composition can be below 45°C.

[0342] In any of the above recording methods, the amount of the transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached can be more than 90% by mass of the total amount of the transparent ink composition adhered in that area.

[0343] In any of the above recording methods, the viscosity increase ratio of the transparent ink composition when the transparent ink composition is mixed with the treatment liquid at a mass ratio of 10:1 can be more than 5 times.

[0344] In any of the above recording methods, the coloring ink composition can be adhered by performing the scan on the same scanning area no more than 5 times.

[0345] In any of the above recording methods, the recording medium may be a low-absorption recording medium or a non-absorption recording medium.

[0346] One embodiment of the recording device is a recording device that records using any of the above-described recording methods, comprising the colored ink composition, the transparent ink composition, and the inkjet head.

[0347] This invention is not limited to the embodiments described above and can be modified in various ways. For example, this invention includes configurations that are substantially the same as those described in the embodiments, such as configurations with the same function, method, and result, or configurations with the same purpose and effect. Additionally, this invention includes configurations that replace non-essential parts of the configurations described in the embodiments. Furthermore, this invention includes configurations that achieve the same function and effect as those described in the embodiments, or configurations that can achieve the same purpose. Additionally, this invention includes configurations that incorporate known techniques into the configurations described in the embodiments.

Claims

1. A recording method, characterized in that, Recording is performed on a recording medium. The recording method involves performing multiple scans, during which the relative position of the inkjet head and the recording medium is moved while ink is ejected from the inkjet head and adhered to the recording medium. The recording method includes the following steps: The process of applying a treatment liquid containing a coagulant to the recording medium; The process of ejecting a coloring ink composition containing colorant from the inkjet head and adhering it to the recording medium; as well as The process of ejecting a resin-containing transparent ink composition from the inkjet head and adhering it to the recording medium. The coloring ink composition is adhered by performing the scan on the same scanning area more than twice. In the final scan of two or more scans, the transparent ink composition is adhered to the scanned area of ​​the recording medium where the colored ink composition is adhered, using the same scan; that is, in the final scan, the colored ink composition and the transparent ink composition are simultaneously adhered to the same area of ​​the recording medium. The amount of the transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached is 80% or more of the total amount of transparent ink composition adhered to in that area. Here, 100% of the total amount of adhered means that the transparent ink composition is adhered to the colored ink composition of the recording medium in the same scan, not in the scan preceding the final scan in the two or more scans mentioned above. The resin contains fixing resin particles. The coagulant comprises one or more selected from cationic resins, organic acids, and polyvalent metal salts.

2. The recording method according to claim 1, characterized in that, The viscosity increase ratio of the transparent ink composition is higher than that of the colored ink composition. The viscosity increase ratio of the transparent ink composition refers to the ratio of the viscosity of the mixture after mixing the transparent ink composition and the treatment liquid at a mass ratio of 10:1 to the viscosity of the transparent ink composition before mixing. The viscosity increase ratio of the colored ink composition refers to the ratio of the viscosity of the mixture after mixing the colored ink composition and the treatment liquid at a mass ratio of 10:1 to the viscosity of the colored ink composition before mixing.

3. The recording method according to claim 1, characterized in that, In the region where the colored ink composition and the transparent ink composition are attached, the region with the highest amount of the colored ink composition attached has a total amount of the transparent ink composition attached relative to the total amount of the colored ink composition attached, which is 5% by mass or more and 70% by mass or less.

4. The recording method according to claim 1, characterized in that, The surface temperature of the recording medium during the process of attaching the coloring ink composition is below 45°C.

5. The recording method according to claim 1, characterized in that, The amount of the transparent ink composition adhered to in the final scan in the area where the colored ink composition and the transparent ink composition are attached is more than 90% by mass of the total amount of the transparent ink composition adhered in that area.

6. The recording method according to claim 1, characterized in that, The viscosity-increasing ratio of the transparent ink composition is more than 5 times. The viscosity-increasing ratio of the transparent ink composition refers to the ratio of the viscosity of the mixture after mixing the transparent ink composition and the treatment liquid at a mass ratio of 10:1 to the viscosity of the transparent ink composition before mixing.

7. The recording method according to claim 1, characterized in that, The coloring ink composition is adhered by performing the scan on the same scanning area no more than 5 times.

8. The recording method according to claim 1, characterized in that, The recording medium is a low-absorption recording medium or a non-absorption recording medium.

9. A recording device, characterized in that, It is a recording apparatus that records using the recording method according to any one of claims 1 to 8. The recording device includes the colored ink composition, the transparent ink composition, and the inkjet head.

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