Active energy ray-curable liquid composition, recording method, and recording device

Abstract

To provide an active energy ray-curable liquid composition which exhibits high aqueous solution characteristics and cured film characteristics when used as an aqueous ink material.SOLUTION: The active energy ray-curable liquid composition contains water and a curable substance and can be cured with an active energy ray. The curable substance contains a monofunctional polymerizable monomer having a structure represented by the following general formula (1). (In the formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group; R2 represents a saturated hydrocarbon group having at least one of a hydroxyl group and an amide bond and optionally containing a heteroatom; R3 represents a hydrogen atom or a methyl group; when R1 is a saturated hydrocarbon group, R1 and R2 may be bonded to form an aliphatic heterocycle together with a substituted nitrogen atom; and the total number of carbon atoms of the saturated hydrocarbon groups represented by R1 and R2 is 5 or more.)SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an active energy ray-curable liquid composition, a recording method using the active energy ray-curable liquid composition as an aqueous ink material, and a recording apparatus.

Background Art

[0002] Conventionally, in an inkjet recording method for image formation, a technique of using an active energy ray-curable liquid composition as an ink is known. When using an active energy ray-curable liquid composition as an ink, it is conceivable to apply a non-aqueous or aqueous curable substance as the curable substance. Examples of inks using a non-aqueous curable substance include so-called oil-based inks in which a pigment is dispersed in an organic solvent, and so-called 100% curable inks (non-solvent inks) that contain a liquid monomer, oligomer, and pigment dispersion without using an organic solvent. However, since the organic solvents or low molecular weight monomers contained in these inks are likely to volatilize into the atmosphere, sufficient consideration for the environment is necessary. In addition, in 100% curable inks, there are also concerns about chemical safety such as skin irritation. Furthermore, since all the ink components applied on the recording medium must be a cured film, unevenness is likely to occur between the recorded and non-recorded portions, and it is difficult to obtain a glossy feeling of the image.

[0003] On the other hand, inks using an aqueous curable substance use an aqueous solvent mainly composed of water as a solvent, so the environmental load due to solvent volatilization is extremely small. It is also possible to suppress the occurrence of unevenness that is a concern when using 100% curable inks. From the above, there is a need to develop a technique of using an active energy ray-curable liquid composition applying an aqueous curable substance to an inkjet recording method, and to develop an aqueous curable substance applicable to the technique. Such aqueous curable substances require various properties such as aqueous solution properties and cured film properties. As means for improving these properties, Patent Document 1 and Patent Document 2 propose using a water-soluble acrylamide-based monomer or its composition.

Prior Art Documents

[0004] [Patent Document 1] Japanese Patent Publication No. 2013-018846 [Patent Document 2] Japanese Patent Publication No. 2012-214561 [Patent Document 3] Japanese Patent Publication No. 2017-160380 [Patent Document 4] Japanese Patent Publication No. 2007-099802 [Overview of the project] [Problems that the invention aims to solve]

[0005] The curable substance disclosed in Patent Document 1 is a water-soluble polyfunctional acrylamide compound having a characteristic structure, achieving both water solubility and photocurability. Furthermore, Patent Document 2 reports an ink composition in which a polyfunctional monomer having the structure described in Patent Document 1 is combined with a monofunctional acrylamide monomer. By combining a monofunctional acrylamide monomer as the curable substance, this composition provides appropriate flexibility to address the problem of the cured film becoming hard and brittle in the structure described in Patent Document 1, resulting in excellent cured film properties. However, since the curable substance is water-soluble before curing, the issue of water resistance remains.

[0006] According to the inventors' research, when using highly water-soluble acrylamide monomers as curable materials, it became clear that there are challenges in achieving both cured film properties and water resistance. Specifically, the curable material described in Patent Document 1 has a tetrafunctional structure, resulting in excessively high crosslinking density and a hard and brittle cured film. To improve this, when a monofunctional monomer described in Patent Document 2 is combined, using a low-molecular-weight, highly hydrophilic, water-soluble monofunctional monomer results in water solubility and good cured film properties. However, it became clear that the crosslinking density decreases, and the high hydrophilicity leads to poor water resistance.

[0007] On the other hand, Patent Document 3 describes an active energy ray curable composition containing an acrylic ester monofunctional monomer having a hydrogen-bonding amide bond in its structure, which exhibits high curing film properties despite being a monofunctional compound due to intramolecular interactions of the amide bond. However, the invention described in Patent Document 3 applies this composition to a non-aqueous ink that does not contain water. When applied to an aqueous ink, as described in Patent Document 4, hydrolysis of the acrylic acid ester causes problems with the stability of the ink.

[0008] The present invention has been made in view of the above problems, and its objective is to provide an active energy ray-curable liquid composition that exhibits high aqueous solution properties and cured film properties when used as an aqueous ink material. Another objective of the present invention is to provide a recording method and recording apparatus that contribute to the formation of high-quality images using the active energy ray-curable liquid composition. [Means for solving the problem]

[0009] According to one aspect of the present invention, an active energy ray-curable liquid composition is provided, which contains water and a curable substance and is curable with active energy rays, wherein the curable substance comprises a monofunctional polymerizable monomer having a structure represented by the following general formula (1);

[0010] [ka]

[0011] (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group which may contain a heteroatom having at least one hydroxyl group and an amide bond, and R3 represents a hydrogen atom or a methyl group. If R1 is a saturated hydrocarbon group, R1 and R2 may bond together with the nitrogen atoms they substitute for to form an aliphatic heterocycle, and the total number of carbon atoms in the saturated hydrocarbon group represented by R1 and R2 is 5 or more.)

[0012] Also, according to one aspect of the present invention, there is provided a recording method having an ink application step of applying an aqueous ink containing an active energy ray-curable liquid composition onto a recording medium, and an active energy ray irradiation step of irradiating the aqueous ink applied onto the recording medium with active energy rays, wherein the active energy ray-curable liquid composition contains water and a curable substance and is curable with active energy rays, and the curable substance contains a monofunctional polymerizable monomer having a structure represented by the above general formula (1).

[0013] Also, according to one aspect of the present invention, there is provided a recording apparatus having an ink application device that applies an aqueous ink containing an active energy ray-curable liquid composition onto a recording medium, and an active energy ray irradiation device that irradiates the aqueous ink applied onto the recording medium with active energy rays, wherein the active energy ray-curable liquid composition contains water and a curable substance and is curable with active energy rays, and the curable substance contains a monofunctional polymerizable monomer having a structure represented by the above general formula (1).

Effects of the Invention

[0014] According to one aspect of the present invention, an active energy ray-curable liquid composition exhibiting high aqueous solution characteristics and cured film characteristics can be obtained when used as an aqueous ink material. Further, according to one aspect of the present invention, a recording method and a recording apparatus contributing to the formation of high-quality images using the active energy ray-curable liquid composition can be obtained.

Brief Description of the Drawings

[0015] [Figure 1] It is a schematic diagram showing the configuration of an inkjet recording apparatus according to an embodiment of the present invention. [Figure 2] It is a schematic diagram showing the configuration of a recording head according to an embodiment of the present invention.

Modes for Carrying Out the Invention

[0016] <Active energy ray-curable liquid composition> Hereinafter, the active energy ray-curable liquid composition according to the present invention (hereinafter also simply referred to as "liquid composition") will be described in detail. The liquid composition according to the present invention contains water and a curable substance containing a monofunctional polymerizable monomer having a structure represented by the following general formula (1), and is a liquid composition curable by active energy rays. The liquid composition may further contain an active energy ray polymerization initiator and other components such as coloring materials.

[0017]

Chemical formula

[0018] (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group which may contain a hetero atom and has at least one of a hydroxyl group and an amide bond, R3 represents a hydrogen atom or a methyl group, and when R1 is a saturated hydrocarbon group, R1 and R2 may be bonded to form an aliphatic heterocyclic ring together with the nitrogen atom to which they are substituted, and the total number of carbon atoms of the saturated hydrocarbon groups represented by R1 and R2 is 5 or more.).

[0019] (1) Curable substance As the curable substance, any substance can be used without particular limitation as long as it contains a monofunctional polymerizable monomer having a structure represented by the above general formula (1). The polymerizable monomer having a structure represented by the above general formula (1) is a (meth)acrylamide-based monofunctional curable substance. In this specification, "(meth)acrylamide" represents "methacrylamide" or "acrylamide". Specifically, the polymerizable group having a structure represented by general formula (1) represents an N-substituted (meth)acrylamide group or an N,N-disubstituted (meth)acrylamide group.

[0020] In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group. Examples of saturated hydrocarbon groups include saturated hydrocarbon groups having 1 to 10 carbon atoms. Specifically, examples include linear or branched alkyl groups having 1 to 10 carbon atoms. When the saturated hydrocarbon group R1 does not bond with R2 to form an aliphatic heterocycle, the saturated hydrocarbon group is preferably a linear or branched alkyl group having 1 to 8 carbon atoms, and more preferably a linear or branched alkyl group having 1 to 4 carbon atoms. Furthermore, when R1 does not bond with R2 to form an aliphatic heterocycle, from the viewpoint of aqueous solution properties (storage stability of aqueous solutions containing polymerizable monomers) and cured film properties, R1 is preferably a hydrogen atom or a methyl group, and particularly preferably a hydrogen atom.

[0021] R2 represents a saturated hydrocarbon group having at least one hydroxyl group and an amide bond, which may contain a heteroatom. Examples of heteroatoms include nitrogen, oxygen, and sulfur atoms. Specific examples of saturated hydrocarbon groups that may contain a heteroatom include saturated hydrocarbon groups containing an ether bond (-O-), a carbonyl bond (-C(=O)-), a sulfone bond (-SO2-), and a sulfonamide bond (-SO2-NH-). The amide bond of R2 may be formed by the carbonyl bond. Examples of saturated hydrocarbon groups include saturated hydrocarbon groups having 1 to 20 carbon atoms. Specifically, examples include linear or branched alkyl groups having 1 to 20 carbon atoms, with linear or branched alkyl groups having 4 to 15 carbon atoms being preferred, and linear or branched alkyl groups having 5 to 10 carbon atoms being more preferred. The saturated hydrocarbon group may also have a cycloalkyl group having 3 to 10 carbon atoms, preferably 5 to 6 carbon atoms. In that case, the total number of carbon atoms in the saturated hydrocarbon group, including the carbon atoms of the cycloalkyl group, is within the range of 1 to 20. Furthermore, one or more carbon atoms constituting the cycloalkyl group may be replaced by a heteroatom to form the amide bond, or a saturated hydrocarbon group (aliphatic heterocycle) which may contain the heteroatom. That is, the saturated hydrocarbon group may have an aliphatic heterocycle. Specifically, the structures of curable materials 9, 10, 14, and 15 shown in Table 1 below fall under this category. These curable materials have a saturated hydrocarbon group having a cyclohexyl group with 6 carbon atoms, in which one or two carbon atoms constituting the cyclohexyl group are replaced by a nitrogen atom or an oxygen atom. The nitrogen atom forms an amide bond with the adjacent carbonyl group, and the oxygen atom forms an ether bond. The aliphatic heterocycle formed by replacing one or more carbon atoms constituting the cycloalkyl group with the heteroatom is preferably a 5-membered ring such as pyrrolidine, imidazolidine, or pyrrolidone, or a 6-membered ring such as piperidine, piperazine, morpholine, or piperidone. Among these, the aliphatic heterocycle is more preferably a 6-membered ring.

[0022] R3 represents either a hydrogen atom or a methyl group. From the viewpoint of reactivity, R3 is preferably a hydrogen atom.

[0023] In general formula (1), if R1 is a saturated hydrocarbon group, R1 and R2 may bond together to form an aliphatic heterocycle with the nitrogen atom they substituted. Examples of aliphatic heterocycles formed by R1 and R2 together with the nitrogen atom of the (meth)acrylamide group include five-membered rings such as pyrrolidine, imidazolidine, and pyrrolidone, or six-membered rings such as piperidine, piperazine, morpholine, and piperidone. Among these, the aliphatic heterocycle is preferably a six-membered ring.

[0024] Furthermore, in the general formula (1) above, the total number of carbon atoms in the saturated hydrocarbon group represented by R1 and the saturated hydrocarbon group represented by R2 is 5 or more. From the viewpoint of water solubility of the monomer, curability, and water resistance of the cured film, the total number of carbon atoms is preferably 5 to 20, and more preferably 5 to 15. Also, for example, in the curable substance 1 below, when R1 is a hydrogen atom and R2 is a linear alkyl group having a hydroxyl group at the terminal, the total number of carbon atoms is preferably 5 to 9. Note that the total number of carbon atoms is the total number of carbon atoms in the saturated hydrocarbon group, so carbon atoms constituting the amide bond in R2 or the carbonyl bond that R2 may contain are not included in the total number of carbon atoms. On the other hand, carbon atoms constituting the cycloalkyl group or aliphatic heterocycle (without unsaturated bonds) that the saturated hydrocarbon group represented by R2 may contain are included in the total number of carbon atoms.

[0025] In general formula (1), if R1 and R2 do not form an aliphatic heterocycle, the total number of carbon atoms of saturated hydrocarbon groups directly bonded to the nitrogen atom of the (meth)acrylamide structure is preferably 5 to 8, from the viewpoint of the water solubility of the monomer, curability, and water resistance of the cured film. More specifically, "the total number of carbon atoms of saturated hydrocarbon groups directly bonded to the nitrogen atom of the (meth)acrylamide structure" means the total number of carbon atoms of saturated hydrocarbon groups represented by R1 and R2 that are "directly" bonded to the (meth)acrylamide structure. That is, for example, in the case of curable substance 5 below, the amide bond of R2 and the carbon atoms of saturated hydrocarbon groups to the right of the amide bond are not included, and the total number of carbon atoms is "5".

[0026] Furthermore, in general formula (1), when R1 and R2 form an aliphatic heterocycle, the total number of carbon atoms of the saturated hydrocarbon group directly bonded to the nitrogen atom of the (meth)acrylamide structure is preferably 4 to 10, from the viewpoint of the water solubility of the monomer, curability, and water resistance of the cured film.

[0027] The amount of monofunctional polymerizable monomer having the structure represented by general formula (1) added is not particularly limited. However, from the viewpoint of ink ejection performance, the amount added is preferably 50% by mass or less of the total amount of the liquid composition. The amount added is more preferably 30% by mass or less, and particularly preferably 20% by mass or less from the viewpoint of gloss uniformity of the image. If the amount of monofunctional polymerizable monomer added is 50% by mass or less, deterioration of gloss uniformity of the obtained image can be suppressed. The amount of monofunctional polymerizable monomer having the structure represented by general formula (1) added can be, for example, 2% by mass or more, preferably 5% by mass or more, of the total amount of the liquid composition.

[0028] The curable substance according to the present invention may contain two or more polymerizable monomers having the structure represented by the general formula (1). Furthermore, it is possible to use a polymerizable monomer having the structure represented by the general formula (1) in combination with other known curable substances as the curable substance. Specific examples of known curable substances include acryloylmorpholine, N-vinylpyrrolidone, acrylamide, hydroxyethylacrylamide, methylenebisacrylamide, monoacrylic acid esters of oligoethylene oxides, and monoacrylic acid esters of dibasic acids. Also, from the viewpoint of cured film properties, it is preferable to use a polyfunctional polymerizable monomer as the curable substance used in combination with a monofunctional polymerizable monomer having the structure represented by the general formula (1). Known commercially available curable substances include polyfunctional polymerizable monomers such as FOM-03008 (water-soluble bifunctional acrylamide), FOM-03007 (water-soluble trifunctional acrylamide), FOM-03006 (water-soluble tetrafunctional acrylamide), and FOM-03009 (water-soluble tetrafunctional acrylamide) (all trade names, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0029] The amount of known curable substances used in combination is not particularly limited. However, if the amount of the known curable substance relative to the polymerizable monomer according to the present invention is too high, the effect of the present invention may decrease. Therefore, when using known curable substances in combination, it is preferable that the ratio of the monofunctional polymerizable monomer having the structure represented by general formula (1) to the total amount of polymerizable monomer (curable substance) contained in the liquid composition is 10% to 90% by mass. It is more preferable that this ratio is 20% to 90% by mass. When combining a polymerizable monomer having the structure represented by general formula (1) and a known curable substance as the curable substance, it is preferable that the total amount of these curable substances be within the range described above, i.e., 50% by mass or less relative to the total amount of the liquid composition. The same applies to more preferable ranges, etc.

[0030] The method for synthesizing polymerizable monomers having the structure represented by general formula (1) of the present invention is not particularly limited. For example, they can be obtained by condensing an amine compound with (meth)acrylate chloride, (meth)acrylic anhydride, etc., using known methods.

[0031] Table 1 below shows specific structures of polymerizable monomers having the structure represented by general formula (1), but the polymerizable monomers are not limited to these structures.

[0032] [Table 1]

[0033] (2) Active energy ray polymerization initiator (hereinafter abbreviated as "polymerization initiator") Polymerization initiators can be used without particular limitations, as long as they can generate active species that initiate polymerization in a curable substance through the exchange of active energy rays. However, since the curing reaction proceeds significantly due to the generation of radicals in the curable substance, polymerization initiators that generate radicals through the exchange of active energy rays are preferred. When the liquid composition according to the present invention is used as an aqueous ink, the polymerization initiator preferably has a water-soluble group in order to maximize its curability. Specific examples of water-soluble groups include hydroxyl groups, carboxylic acid groups, sulfonic acid groups, phosphate groups, carboxylic acid bases, sulfonic acid bases, phosphate bases, ether groups, and amide groups. Furthermore, when used in combination with a colorant having an anionic group, it is necessary to have an organic group other than an ester group in order to suppress hydrolysis. Specific examples of polymerization initiators include the following compounds A to C, but the polymerization initiator is not limited to these.

[0034] [ka]

[0035] Furthermore, in the present invention, the polymerization initiator and sensitizer may be used in combination, or two or more polymerization initiators may be used in combination. By using two or more polymerization initiators in combination, it is possible to expect the generation of further radicals by utilizing active energy rays at wavelengths that cannot be effectively utilized with a single polymerization initiator. Note that the polymerization initiator is not necessarily required when employing an electron beam curing method in which an electron beam is used as the active energy ray to cure the liquid composition.

[0036] The content of the polymerization initiator is preferably in the range of 0.01% to 20% by mass, more preferably in the range of 0.01% to 10% by mass, and even more preferably in the range of 0.01% to 5% by mass, relative to the total amount of the liquid composition. If the content of the polymerization initiator is 20% by mass or less, it is possible to suppress the decrease in the strength of the cured film caused by unreacted polymerization initiator remaining in the cured film.

[0037] (3) Solvent The liquid composition according to the present invention contains at least water as a solvent, and may further contain an organic solvent as needed. The water is not particularly limited, but ion-exchanged water, distilled water, etc., can be used. The water content varies depending on the application and form, so it cannot be stated in general terms, but it is preferably 10% by mass or more of the total amount of the liquid composition. In particular, when the liquid composition is applied as an aqueous ink for use in an inkjet recording system, the water content is preferably 30% by mass or more, and more preferably 50% by mass or more of the total amount of the liquid composition. The water content can be, for example, 90% by mass or less of the total amount of the liquid composition.

[0038] Organic solvents are added to inks for purposes such as imparting non-volatility of water, adjusting the viscosity and surface tension of the ink, and imparting wettability to recording media. When adding organic solvents, the amount of organic solvent added can be 0.1% to 40% by mass relative to the total amount of the liquid composition. The following is a list of organic solvents that can be used in the present invention. Any of these can be added to the liquid composition of the present invention. Glycol ethers such as ethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monomethyl ether, and propylene glycol monomethyl ether; monohydric alcohols such as methanol, ethanol, propanol, butanol, and pentanol; polyhydric alcohols such as glycerin, polyethylene glycol, propylene glycol, polypropylene glycol, butanediol, heptanediol, and hexanediol; and amides such as 2-pyrrolidone.

[0039] Furthermore, in this invention, the curable substance may be used as an emulsion by emulsifying and dispersing it using known dispersion techniques, rather than completely dissolving it in the solvent. Similarly, various encapsulation techniques can be used.

[0040] (4) Other ingredients Furthermore, the liquid composition according to the present invention may contain a colorant. When a colorant is included, the liquid composition according to the present invention can be used as a certain type of ink. When a colorant is included, the colorant content is preferably 0.3% to 15% by mass relative to the total amount of the liquid composition. The composition and colorants used when a colorant is included will be described below. The liquid composition of the present invention can be used as a colored active energy ray-curable ink by applying it to an ink containing a colorant, which hardens upon irradiation with active energy rays. In this case, a pigment dispersion in which pigments are uniformly dispersed in an aqueous medium is preferred as the colorant. As the pigment dispersion, aqueous gravure inks, aqueous pigment dispersions for writing instruments, and conventionally known pigment dispersions used in inkjet inks can all be suitably used. Among these, a pigment dispersion in which pigments are stably dispersed in an aqueous medium by anionic groups is extremely preferred.

[0041] Pigment dispersions in which pigments are stably dispersed in an aqueous medium by anionic groups are disclosed in Japanese Patent Publication No. 8-143802, Japanese Patent Publication No. 8-209048, Japanese Patent Publication No. 10-140065, U.S. Patent No. 5,837,045, and U.S. Patent No. 5,851,280. In the liquid composition of the present invention, various pigment dispersions as described above can be used as colorants.

[0042] Other pigments that can be used include carbon black and organic pigments. Examples of carbon black include furnace black, lamp black, acetylene black, and channel black. Of course, other conventionally known carbon blacks can also be used. In addition, magnetic material fine particles such as magnetite and ferrite, or titanium black may be used as pigments. Examples of organic pigments that can be used include the following: Azo pigments such as toluidine red and Hansa yellow. Phthalocyanine pigments such as phthalocyanine blue and phthalocyanine green. Quinacridone pigments such as quinacridone red and quinacridone magenta. Perylene pigments such as perylene red and perylene scarlet. Isoindolinone pigments such as isoindolinone yellow and isoindolinone orange. Imidazolone pigments such as benzimimidazolone yellow and benzimimidazolone orange. Pyrencelone pigments such as pyrencelone red and pyrencelone orange.

[0043] The following lists the available organic pigments by their Color Index (CI) numbers. CI Pigment Yellow: 12, 13, 14, 17, 20, 24, 55, 74, 83, 86, 93, 97, 98, 109, 110, 117, 120, 125, 128, 137, 138, 139, etc. CI Pigment Yellow: 147, 148, 150, 151, 153, 154, 155, 166, 168, 180, 185, etc. CI Pigment Orange: 16, 36, 43, 51, 55, 59, 61, 71, etc. CI Pigment Red: 9, 48, 49, 52, 53, 57, 97, 122, 123, 149, 168, 175, 176, 177, 180, 192, 202, 209, 215, 216, 217, etc. Also, CI Pigment Red: 220, 223, 224, 226, 227, 228, 238, 240, 254, 255, 272, etc. CI Pigment Violet: 19, 23, 29, 30, 37, 40, 50, etc. CI Pigment Blue: 15, 15:1, 15:3, 15:4, 15:6, 22, 60, 64, etc. CI Pigment Green: 7, 36, etc. CI Pigment Brown: 23, 25, 26, etc. Of course, in addition to these, various conventionally known organic pigments can also be used.

[0044] Furthermore, when using the above-mentioned pigments, a dispersant may be used in combination. The dispersant is not particularly limited as long as it can stably disperse the pigment in an aqueous medium, but for example, block polymers, random polymers, graft polymers, etc., can be used. Examples are listed below. Styrene-acrylic acid copolymer, styrene-maleic acid copolymer, vinylnaphthalene-acrylic acid copolymer, vinylnaphthalene-maleic acid copolymer, or salts thereof, etc. Benzyl methacrylate-methacrylic acid copolymer, or salts thereof, etc. Furthermore, when using the various pigments mentioned above, it is also possible to use so-called self-dispersing pigments, which allow the pigment particles to be dispersed in a medium without the use of a dispersant by bonding ionic groups to the surface of the pigment particles.

[0045] The liquid composition of the present invention can also use various dyes as colorants. The dyes that can be used are shown below by their color index (CI) numbers. CI Acid Yellow 11, 17, 23, 25, 29, 42, 49, 61, 71, etc. CI Direct Yellow 12, 24, 26, 44, 86, 87, 98, 100, 130, 132, 142, etc. CI Acid Red 1, 6, 8, 32, 35, 37, 51, 52, 80, 85, 87, 92, 94, 115, 180, 254, 256, 289, 315, 317, etc. CI Direct Red 1, 4, 13, 17, 23, 28, 31, 62, 79, 81, 83, 89, 227, 240, 242, 243, etc. CI Acid Blue: 9, 22, 40, 59, 93, 102, 104, 113, 117, 120, 167, 229, 234, 254, etc. CI Direct Blue: 6, 22, 25, 71, 78, 86, 90, 106, 199, etc. CI Direct Black: 7, 19, 51, 154, 174, 195, etc.

[0046] The liquid composition of the present invention can also be used in the form of a "transparent ink," so to speak, without containing the aforementioned colorant. In this case, since it does not contain a colorant, a substantially colorless and transparent film can be obtained. Examples of applications for such a "transparent ink" include the following: for example, an undercoat to impart various suitability for image recording to a recording medium, or an overcoat for surface protection of an image formed with ordinary ink, or for decoration or glossing purposes. In this case, the liquid composition of the present invention may also contain dispersed colorless pigments or fine particles that are not intended for coloring, depending on the application, such as oxidation prevention or fading prevention. By adding these, various properties such as image quality, robustness, and workability (handling) of the recorded material can be improved in both undercoats and overcoats.

[0047] Furthermore, the liquid composition according to the present invention may contain surfactants, curing accelerators, crosslinking agents, water-soluble additives, and viscosity modifiers. The surfactants and the like can be appropriately selected from known sources.

[0048] Examples of active energy rays used to cure the liquid composition of the present invention include electron beams, ultraviolet rays, alpha rays, beta rays, gamma rays, and X-rays. Among these, ultraviolet rays are preferred. The cumulative irradiation energy is, for example, 20 mJ / cm². 2 ~20,000 mJ / cm² 2 This can be done. Furthermore, the cumulative irradiation energy can be appropriately adjusted depending on the components contained in the liquid composition, such as the presence and type of colorants.

[0049] <Recording device> The recording device according to the present invention comprises at least an ink dispensing device for dispensing an aqueous ink containing the active energy ray curable liquid composition according to the present invention onto a recording medium, and an active energy ray irradiation device for irradiating the aqueous ink dispensed onto the recording medium with active energy rays. The ink dispensing device may be any recording method capable of dispensing the aqueous ink according to the present invention onto a recording medium. The liquid composition according to the present invention provides particularly excellent effects when applied to an inkjet recording device. That is, it is preferable that the ink dispensing device is equipped with a recording head that ejects ink in an inkjet recording method. Furthermore, the liquid composition according to the present invention is very effective both as a liquid contained in a cartridge having a liquid storage section (liquid cartridge) and as a filling liquid for said liquid cartridge. In addition, the liquid composition according to the present invention has a structure containing flexible amide bonds and saturated hydrocarbon bonds. Therefore, it exhibits excellent adhesion to various recording media such as non-absorbent media such as PET, PC, and PMMA, poorly absorbent media such as glossy paper for offset printing, and absorbent media such as PPC paper.

[0050] An inkjet recording device is equipped with a recording head that ejects ink using an inkjet recording method. A preferred inkjet recording method is one that uses thermal energy to eject ink, as it allows for easy implementation of high-density multi-orifice recording of the recording head and enables high-resolution and high-quality image recording at high speed. As a recording head that ejects ink by applying thermal energy, it is preferable to adopt the basic principles disclosed in, for example, U.S. Patent No. 4,723,129 and U.S. Patent No. 4,740,796. Such a system is applicable to both so-called on-demand and continuous types. In the case of an on-demand type, it is preferable to apply at least one drive signal that corresponds to the recording information and causes a rapid temperature rise exceeding nucleation boiling to an electrothermal converter positioned in accordance with the sheet or liquid channel in which the ink is held. This generates thermal energy in the electrothermal converter, causing film boiling on the thermal surface of the recording head, and as a result, it is effective in forming bubbles in the ink in a one-to-one correspondence with this drive signal. The growth and contraction of bubbles causes ink to be ejected from the nozzle, forming at least one droplet. A pulsed drive signal is preferable because it allows for immediate and appropriate bubble growth and contraction, resulting in particularly responsive ink ejection. Suitable pulsed drive signals include those described in U.S. Patent Nos. 4,463,359 and 4,345,262. Furthermore, it is preferable to adopt the conditions regarding the rate of temperature rise on the thermally acting surface, as described in U.S. Patent No. 4,313,124.

[0051] Suitable recording head configurations include those disclosed in the above-mentioned specifications, which combine a discharge port, a liquid channel, and an electrothermal converter (linear liquid channel or right-angle liquid channel). Other suitable configurations include those disclosed in U.S. Patent No. 4,558,333 and U.S. Patent No. 4,459,600, which involve the thermal working section being located in a bent region. Furthermore, the atmospheric discharge method described in Japanese Patent No. 2962880, Japanese Patent No. 3246949, and Japanese Patent Application Publication No. 11-188870 is also effective. Additionally, configurations where a common discharge port serves as the discharge section for multiple electrothermal converters (e.g., Japanese Patent Application Publication No. 59-123670) are also effective.

[0052] The following can be used as a full-line type recording head having a length corresponding to the maximum width of the recording medium that the inkjet recording device can record on. For example, it may be a configuration that satisfies the length by combining multiple recording heads as disclosed in the above specification, or a configuration as a single recording head formed integrally. Furthermore, interchangeable chip-type recording heads that can be attached to the inkjet recording device to enable electrical connection with the device body and ink supply from the device body, and cartridge-type recording heads that are integrally provided with the recording head are also effective.

[0053] It is also preferable to add means for recovering the recording head or auxiliary means. Specifically, these include means for capping the recording head, cleaning means, pressurizing or suction means, electrothermal converter, heating element, preheating means, and pre-discharge mode.

[0054] Figure 1 is a schematic perspective view showing an example of the configuration of an inkjet recording device. The inkjet recording device shown in Figure 1 employs a shuttle system that uses a short serial head and records while scanning the head in the width direction of the recording medium. The carriage 100 is connected to an endless belt 101 and is movable along the guide shaft 102. The endless belt 101 is stretched between pulleys 103 and 104. The drive shaft of the motor 105 is connected to the pulley 103. Therefore, the carriage 100 reciprocates along the guide shaft 102 in the main scanning direction indicated by arrow A by the rotational drive of the motor 105. The carriage 100 is equipped with a recording head (not shown) having multiple ink ejection nozzles arranged in parallel, and an ink tank IT which serves as a container for storing ink. An active energy ray irradiation unit 20 is provided at least one end of the carriage 100 in the main scanning direction A. Therefore, it is possible to irradiate the recording surface with active energy rays from the active energy ray irradiation unit 20 immediately after ink is applied to the recording medium. Examples of active energy rays include electron beams, ultraviolet rays, alpha rays, beta rays, gamma rays, and X-rays. Among these, ultraviolet rays are preferred. This active energy ray irradiation unit 20 is an active energy ray irradiation device that irradiates the ink applied to the recording medium with active energy rays. In Figure 1, active energy ray irradiation units 20 are provided at both ends of the carriage 100. Irradiation with active energy rays may be performed immediately after ink application, as shown in the figure, or it may be performed at a certain interval after ink application if the recording medium is ink absorbent. Furthermore, the active energy rays are not limited to a single irradiation, but may be irradiated in multiple stages.

[0055] The recording head has multiple ink ejection ports formed on the ejection port surface facing the paper P, which serves as the recording medium, arranged in the direction of transport of the paper P (the sub-scanning direction of arrow B). The recording head is also provided with ink paths that communicate with each of the multiple ink ejection ports. Corresponding to each ink path, an electrothermal converter is provided to generate thermal energy for ejecting the ink. The electrothermal converter generates heat when electrical pulses corresponding to the drive data are applied. This heat causes film boiling in the ink, and as bubbles are generated, ink is ejected from the ink outlet. Each ink path is connected to a common liquid chamber, which is connected to the ink tank IT.

[0056] The inkjet recording device shown in Figure 1 is equipped with a linear encoder 106 for detecting the movement position of the carriage 100. Specifically, a linear scale 107 provided along the direction of movement of the carriage 100 has, for example, 1,200 slits formed at equal intervals over a one-inch period. On the carriage 100 side, for example, a slit detection system 108 having a light-emitting unit and a light-receiving sensor, and a signal processing circuit are provided. Therefore, the linear encoder 106 outputs an ejection timing signal indicating the ink ejection timing, and information on the movement position of the carriage 100, in accordance with the movement of the carriage 100. By ejecting ink each time a slit on the linear scale 107 is detected, an image with a resolution of 1,200 dpi can be recorded in the main scanning direction. The paper P, which serves as the recording medium, is intermittently transported in the sub-scanning direction indicated by arrow B, which is perpendicular to the operating direction of the carriage 100. The paper P is supported by a pair of roller units 109 and 110 on the upstream side of the transport direction and a pair of roller units 111 and 112 on the downstream side of the transport direction. A constant tension is applied, and the paper is transported while ensuring flatness relative to the recording head. The driving force for roller units 111 and 112 is supplied from a paper transport motor (not shown).

[0057] In the inkjet recording device shown in Figure 1, an image can be recorded on the entire sheet of paper P by moving the carriage 100 and alternately repeating the process of recording a width corresponding to the arrangement width of the recording head's ejection ports and feeding the paper P. The carriage 100 stops at the home position as needed at the start of recording or during recording. At this home position, a cap member 113 is provided that caps the ejection surface side of each recording head. A suction recovery means (not shown) is connected to this cap member 113 to forcibly absorb ink from the ejection port and prevent clogging of the ejection port.

[0058] In addition to the shuttle method described above, there is also a line method that uses a line head in which recording elements are arranged to cover the entire area of ​​one side of the recording medium. In the line method, the recording medium is scanned in a direction perpendicular to the direction of the arrangement of recording elements, allowing image recording to be performed across the entire surface of the recording medium. Therefore, a transport system such as a carriage that scans the short head is unnecessary. Furthermore, complex scanning control between the movement of the carriage and the recording medium is unnecessary, and only the recording medium moves, so the recording speed can be increased compared to the shuttle method.

[0059] <Recording Method> The recording method according to the present invention comprises at least an ink application step of applying an aqueous ink containing the active energy ray-curable liquid composition according to the present invention onto a recording medium, and an active energy ray irradiation step of irradiating the aqueous ink applied onto the recording medium with active energy rays. The ink application step may be any recording method capable of applying the aqueous ink according to the present invention to the recording medium, but it is particularly preferable to perform it using an inkjet recording method.

[0060] As described in detail above with reference to preferred embodiments, the present invention provides an active energy ray-curable liquid composition that, when used as an aqueous ink material, has excellent aqueous solution properties and cured film properties. Furthermore, the present invention provides an active energy ray-curable liquid composition that, when applied to an inkjet recording device, exhibits excellent ejection performance regardless of the ejection method, and also exhibits high long-term storage stability. [Examples]

[0061] The present invention will be described in more detail below with reference to more specific examples and comparative examples of the active energy ray curable liquid composition according to the present invention. The curable substances used in the examples of the present invention were selected from the curable substances shown in Table 1 above. In the comparative examples, the curable substances shown in Table 2 below (hereinafter referred to as "comparative compounds") were used. Comparative compound 1 is trade name: DAAM (diacetone acrylamide, manufactured by KJ Chemicals Co., Ltd.), comparative compound 2 is trade name: HEAA (N-hydroxyethyl acrylamide, manufactured by KJ Chemicals Co., Ltd.), and comparative compound 3 is trade name: ACMO (acryloyl morpholine, manufactured by KJ Chemicals Co., Ltd.). Comparative compounds 4 and 5 were synthesized. The synthesis methods for comparative compounds 4 and 5 will be described later.

[0062] [Table 2]

[0063] (1) Synthesis of curable materials [Synthesis Example 1: Synthesis of curable substances 2, 3, and 16, and comparative compounds 4 and 5] Under light-shielding conditions, 87.3 g (1.21 mol) of acrylic acid was added to 484 ml of THF to form a liquid. 1000 ppm of hydroquinone and 25 g (0.242 mol) of 4-amino-3-methyl-1-butanol were added, and the mixture was stirred for 30 minutes. To the resulting liquid, 67 g (0.242 mol) of DMT-MM (4,6-dimethoxy-1,3,5-triazine-2-yl)-4-methylmorpholinium chloride) was added, and the mixture was stirred for 2 hours. The resulting liquid was filtered through Celite filtration, and the obtained filtrate was washed with 400 mL of THF. The washed filtrate was concentrated and purified by silica gel column chromatography. The target product was separated, and the mixture was concentrated with 500 ppm of methoxyphenol, a polymerization inhibitor, to obtain curable substance 2.

[0064] Furthermore, curable substance 3 was obtained using the same synthesis method as curable substance 2, except that 4-amino-3-methyl-1-butanol was replaced with 6-amino-1-hexanol. Furthermore, curable substance 16 was obtained using the same synthesis method as curable substance 2, except that 4-amino-3-methyl-1-butanol was replaced with 8-amino-1-octanol. Furthermore, comparative compound 4 was obtained using the same synthesis method as for curable substance 2, except that 4-amino-3-methyl-1-butanol was replaced with 3-amino-1-propanol. Furthermore, comparative compound 5 was obtained using the same synthesis method as for curable substance 2, except that 4-amino-3-methyl-1-butanol was replaced with 4-amino-1-butanol.

[0065] [Synthesis Example 2: Synthesis of Curable Substance 4] Under light-shielding conditions, 44 g (0.341 mol) of 4-piperidineethanol was added to 440 ml of THF to form a liquid. 1000 ppm of hydroquinone and 35.1 g (0.511 mol) of ice-cold acrylic acid were added, and the mixture was stirred for 30 minutes. To the resulting liquid, 94.4 g (0.341 mol) of DMT-MM was added, and the mixture was stirred for 3 hours to allow the reaction to proceed. The resulting liquid was filtered through Celite filtration, and the obtained filtrate was washed with 400 mL of THF. The washed filtrate was concentrated and purified by silica gel column chromatography. The target product was separated, and the mixture was concentrated with 500 ppm of methoxyphenol, a polymerization inhibitor, to obtain curable substance 4.

[0066] [Synthesis Example 3: Synthesis of curable substances 5, 8, 12, and 13] A compound was obtained in which the OH group of curable substance 1 was replaced with a COOH group by the same synthesis method as for curable substance 2, except that 4-amino-3-methyl-1-butanol was replaced with 6-aminohexanoic acid. 35 g (0.189 mol) of this compound was added to 700 ml of methylene chloride to form a liquid, to which 1000 ppm of hydroquinone was added and the mixture was stirred for 30 minutes. To the resulting liquid, 36.2 g (0.189 mol) of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide (a water-soluble carbodiimide WSC) and 21.1 g (0.282 mol) of 2-methoxyethylamine were sequentially added and the mixture was stirred for 1.5 hours. Methanol was added to the resulting liquid, which was then concentrated and purified by silica gel column chromatography. The target product was then separated and concentrated to obtain curable substance 5.

[0067] Furthermore, curable substance 8 was obtained using the same synthesis method as curable substance 5, except that 2-methoxyethylamine was replaced with N,N'-diethylamine. Furthermore, curable substance 12 was obtained using the same synthesis method as curable substance 5, except that 2-methoxyethylamine was replaced with 2-amino-1-propanol. Furthermore, curable substance 13 was obtained using the same synthesis method as curable substance 5, except that 2-methoxyethylamine was replaced with 4-amino-2-methyl-1-butanol.

[0068] (2) Preparation of ink [Examples 1-8, Comparative Examples 1-5] Using the curable substances shown in Tables 3-1 and 3-2 below, inks 1-8 and C1-C5, consisting of active energy ray curable liquid compositions according to Examples 1-8 and Comparative Examples 1-5, were prepared with the following compositions. Among the components listed below, "Acetylenel E100" is the trade name of a nonionic surfactant (ethylene oxide adduct of acetylene glycol) manufactured by Kawaken Fine Chemicals Co., Ltd. (Ink composition) ·Curing substance: 20% by mass • Active energy ray polymerization initiator (compound A): 2% by mass • Surfactant (Acetylenel E100 (product name, manufactured by Kawaken Fine Chemical Co., Ltd.)): 1% by mass • Ion-exchanged water: 77% by mass

[0069] (3) Evaluation of the water solubility properties of ink (liquid composition) (storage stability of aqueous solutions containing polymerizable monomers) The storage stability of aqueous solutions (water-based inks) containing polymerizable monomers was evaluated by visually observing the presence or absence of undissolved polymerizable monomers in the inks after standing, following the standing period. As a result, it was confirmed that polymerizable monomers were dissolved in the inks in all inks 1-8 and C1-C5, and that the polymerizable monomers were not separated from the inks.

[0070] (4) Formation of a cured film using bar coating The obtained inks 1-8 and C1-C5 were bar-coated onto PET film (product name: Easy-Adhesion White PET, manufactured by Teijin Corporation) at a rate of 10 g / m². 2 The coating was applied to form a film. Subsequently, a UV-LED irradiation device manufactured by Ushio Inc. (product name: L60II, wavelength 395nm) was used to irradiate the area at 1,000 mJ / cm². 2 The coating was irradiated with the accumulated irradiation energy to form a cured film.

[0071] (5) Evaluation of the properties of the cured film (scratch resistance) Three hours after the formation of the hardened film, each formed hardened film was subjected to a pencil hardness test in accordance with JIS K 5600-5-4:1999 (scratch hardness (pencil method)). The degree of scratches and peeling other than indentations was observed visually, and the abrasion resistance was evaluated according to the following evaluation criteria. The evaluation results are shown in Tables 3-1 and 3-2. In the tables, "4B" for pencil hardness means that although it is a D rank, peeling does not occur with a 4B pencil, and "5B or less" means that peeling occurs even with a 4B pencil. A: Even with a 2H pencil hardness, no scratches or peeling were observed. B: No scratches or peeling were observed with pencils of hardness H or lower. C: No scratches or peeling were observed with pencils of HB hardness or lower. D: Even pencils with a hardness of 2B or lower showed signs of scratches or peeling.

[0072] [Table 3-1]

[0073] [Table 3-2]

[0074] [Examples 9-17] (1) Preparation of ink 9 The pigment (CI Pigment Red 122) and the dispersant (a random copolymer of styrene / acrylic acid / ethyl acrylate, weight-average molecular weight = 3,500, acid value = 150 mg KOH / g) were mixed and then dispersed in a bead mill. This yielded a magenta pigment dispersion with a pigment solids content of 10% by mass and a pigment:dispersant (mass ratio) of 3:1. Next, the components listed below were mixed and thoroughly stirred, and the mixture was pressure filtered through a pore size 0.5 μm filter to obtain ink 9 (magenta ink). The pH of the obtained magenta ink was 9. In the components listed below, "FOM-03008" is the trade name of a curable substance (water-soluble bifunctional acrylamide) manufactured by Fujifilm Wako Pure Chemical Industries, Ltd. (Composition of Ink 9) • Magenta pigment dispersion: 40% by mass ·Curable substance 13: 17% by mass • Polymerizable monomer (FAM-03008 (product name, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)): 3% by mass • Active energy ray polymerization initiator (compound A): 3% by mass • Surfactant (Acetylenel E100 (product name, manufactured by Kawaken Fine Chemical Co., Ltd.)): 1% by mass • Ion-exchanged water: 36% by mass

[0075] (2) Formation of a cured film using an inkjet recording device (image recording) Inks 1-8 and the magenta ink 9 prepared in Examples 1-8 were mounted on an on-demand inkjet recording device (product name: Pro-10, manufactured by Canon Corporation) that dispenses ink by applying thermal energy corresponding to the recording signal. A UV-LED irradiation device (product name: M30, manufactured by Ushio Inc., wavelength 395 nm) was mounted adjacent to the recording head of this recording device. Specifically, as shown in Figure 2, the above device was mounted as a UV-LED irradiation device 30 at a location adjacent to the mounting position (10) (GY cartridge mounting position) at the ink cartridge mounting position 50 of the recording head 10. The integrated irradiation energy of the active energy ray under unidirectional 1-pass drawing conditions was 2,000 mJ / cm². 2This was the case. In this inkjet recording device, a recording duty cycle of 100% is defined as an image recorded under the conditions of a resolution of 600 dpi x 600 dpi and applying 8 drops of 3.8 ng of ink to a unit area of ​​1 / 600 inch x 1 / 600 inch. Using this inkjet recording device, images were recorded on PET film (product name: Easy-Adhesion White PET, manufactured by Teijin Corporation) as shown in (3) below, and each characteristic was evaluated.

[0076] (3) Image Characterization [Evaluation of discharge characteristics] (Basic discharge properties) Using inks 1-8 and magenta ink 9, along with the inkjet recording device described above, suction recovery was performed, and after being left for 1 minute, a 1200 dpi, 100% duty solid image was printed in one pass. No UV irradiation was performed after printing. The condition of the printed solid image was visually observed, and the basic ink ejection performance was evaluated based on the following evaluation criteria. The evaluation results are shown in Table 4. A: A uniform solid image was formed, and no image blurring was observed. C: Blurring was observed at the beginning of the image output (not detected).

[0077] (Storage stability) In the evaluation of basic ejection performance, the storage stability of the ink was evaluated using the same methods and evaluation criteria as the basic ejection performance evaluation, except that it was left for 3 days after the aspiration was restored. The evaluation results are shown in Table 4.

[0078] [Evaluation of cured film properties] (Abrasion resistance) Using inks 1-8 and magenta ink 9, and the above-mentioned inkjet recording device, a 100% solid image was formed on a PET film (product name: Easy-Adhesion White PET, manufactured by Teijin). Then, the same irradiation conditions as those used for image recording described in (2) above (cumulative irradiation energy: 2,000 mJ / cm²) were used. 2Ultraviolet light was irradiated in parallel with the recording process to obtain a cured film (image). Three hours after the cured film formed, a pencil hardness test was performed in accordance with JIS K 5600-5-4:1999 (scratch hardness (pencil method)). The degree of scratches and peeling other than indentations was observed visually, and the abrasion resistance of the ink was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 4. A: Even with a 2H pencil hardness, no scratches or peeling were observed. B: No scratches or peeling were observed with pencils of hardness H or lower. C: No scratches or peeling were observed with pencils of HB hardness or lower. D: Pencils with a hardness of 2B or lower showed signs of scratches or peeling.

[0079] (water resistance) Using the prepared inks 1-8 and magenta ink 9, and the inkjet recording device described above, a 100% solid image was formed on a PET film (product name: Easy-Adhesion White PET, manufactured by Teijin). Then, under the same irradiation conditions as those used for image recording described in (2) above, ultraviolet light was irradiated in parallel with the recording to obtain a cured film (image). One day after the formation of the cured film, 0.2 ml of deionized water was dropped onto the image on the recording medium, and after 1 minute, a sheet of Silbon paper was placed on the image, with a density of 40 g / cm² on the recording surface. 2 The lens tissue was pulled while a load was applied. Then, it was visually observed whether the image portion of the recording medium peeled off due to friction. Furthermore, it was visually observed whether staining occurred on the non-recording area (white area) and the lens tissue due to friction of the image portion, and the water resistance of the ink was evaluated according to the following evaluation criteria. The evaluation results are shown in Table 4. A: Peeling of the image due to friction covered less than 3% of the coating area, and areas with no dirt at all covered more than 90% of the surface area of ​​the lens paper. C: The area of ​​the image peeling due to abrasion was 3% or more of the total area of ​​the coating film, or the area where no dirt was observed was less than 90% of the total area of ​​the Silbon paper.

[0080] [Table 4]

[0081] [Examples 18-20] (1) Preparation of ink A yellow pigment dispersion was obtained in the same manner as for magenta ink 9, except that CI Pigment Yellow 13 was used as the pigment instead of CI Pigment Red 122. The obtained yellow pigment dispersion had a pigment solid content of 10% by mass, a pigment:dispersant (mass ratio) of 3:1, and an average particle size of 130 nm. Similarly, a cyan pigment dispersion was obtained in the same manner as for magenta ink 9, except that CI Pigment Blue 15:3 was used as the pigment instead of CI Pigment Red 122. The obtained cyan pigment dispersion had a pigment solid content of 10% by mass, a pigment:dispersant (mass ratio) of 3:1, and an average particle size of 125 nm. Then, ink 10 (yellow ink) and ink 11 (cyan ink) were prepared in the same manner as magenta ink 9, except that yellow pigment dispersion and cyan pigment dispersion were used instead of magenta pigment dispersion, respectively.

[0082] (2) Image Characterization The prepared yellow ink 10, cyan ink 11, and magenta ink 9 were evaluated for their properties in the same manner as in Example 9. However, for the evaluation of "cured film properties," offset recording paper (product name: OK Kinto, manufactured by Mitsubishi Paper Mills Ltd.) was used instead of PET film. The results are shown in Table 5. Furthermore, when magenta ink 9 and cyan ink 11 were combined in a 1:1 ratio to form a two-color ink set, and the same evaluation was performed using this ink set, the same results as those shown in Examples 18 to 20 were obtained.

[0083] [Table 5]

[0084] Furthermore, the disclosure of this embodiment includes the following configurations and methods. (Composition 1) An active energy ray curable liquid composition containing water and a curable substance, which can be cured with active energy rays, characterized in that the curable substance contains a monofunctional polymerizable monomer having a structure represented by the following general formula (1);

[0085] [ka]

[0086] (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group which may contain a heteroatom having at least one hydroxyl group and an amide bond, and R3 represents a hydrogen atom or a methyl group. If R1 is a saturated hydrocarbon group, R1 and R2 may bond together with the nitrogen atoms they substitute for to form an aliphatic heterocycle, and the total number of carbon atoms in the saturated hydrocarbon group represented by R1 and R2 is 5 or more.)

[0087] (Configuration 2) The active energy ray curable liquid composition according to Configuration 1, wherein, in the general formula (1), when R1 and R2 do not form the aliphatic heterocycle, the total number of carbon atoms of the saturated hydrocarbon group directly bonded to the nitrogen atom of the (meth)acrylamide structure is 5 to 8. (Configuration 3) The active energy ray curable liquid composition according to Configuration 1, wherein in the general formula (1), R1 is a saturated hydrocarbon group, and R1 and R2 are bonded to form a five-membered or six-membered aliphatic heterocycle. (Configuration 4) The active energy ray curable liquid composition according to Configuration 3, wherein in the general formula (1), the total number of carbon atoms of the saturated hydrocarbon group directly bonded to the nitrogen atom of the (meth)acrylamide structure is 4 to 10. (Configuration 5) The active energy ray curable liquid composition according to any one of Configurations 1 to 4, wherein in the general formula (1), the total number of carbon atoms in the saturated hydrocarbon groups represented by R1 and R2 is 5 to 20. (Composition 6) An active energy ray curable liquid composition according to any one of Compositions 1 to 5, further comprising a polyfunctional polymerizable monomer. (Configuration 7) The active energy ray curable liquid composition according to any one of Configurations 1 to 6, wherein the water content relative to the total amount of the active energy ray curable liquid composition is 30% by mass or more. (Configuration 8) The active energy ray curable liquid composition according to Configuration 6 or 7, wherein the ratio of the monofunctional polymerizable monomer to the total amount of polymerizable monomers contained in the active energy ray curable liquid composition is 10% by mass to 90% by mass.

[0088] (Method 1) An ink application step of applying an aqueous ink containing an active energy ray curable liquid composition described in any of the configurations 1 to 8 onto a recording medium, An active energy ray irradiation step is performed by irradiating the aqueous ink applied to the recording medium with active energy rays. A recording method having the following characteristics. (Method 2) The recording method according to Method 1, wherein the ink application step is performed by an inkjet recording method.

[0089] (Configuration 9) An ink dispensing device that dispenses an aqueous ink containing the active energy ray curable liquid composition described in any of Configurations 1 to 8 onto a recording medium, An active energy ray irradiation device that irradiates an aqueous ink applied to the recording medium with active energy rays, A recording device having the following features. (Configuration 10) The recording device according to Configuration 9, wherein the ink dispensing device includes a recording head that ejects ink in an inkjet recording manner. [Explanation of Symbols]

[0090] 10 Recording head 20 Active energy ray irradiation section IT Ink Tank

Claims

1. An active energy ray-curable liquid composition which contains water and a curable substance and is curable with active energy rays, the active energy ray-curable liquid composition being characterized in that the curable substance contains a monofunctional polymerizable monomer having a structure represented by the following general formula (1): 【Chemistry 1】 (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group having at least one of a hydroxyl group and an amide bond and which may contain a heteroatom, and R3 represents a hydrogen atom or a methyl group, and when R1 is a saturated hydrocarbon group, R1 and R2 may be bonded to form an aliphatic heterocycle together with the nitrogen atom which they substitute, and the total number of carbon atoms of the saturated hydrocarbon group represented by R1 and R2 is 5 or more.)

2. 2. The active energy ray-curable liquid composition according to claim 1, wherein, in the general formula (1), when R1 and R2 do not form the aliphatic heterocycle, a total number of carbon atoms in the saturated hydrocarbon group directly bonded to a nitrogen atom of the (meth)acrylamide structure is 5 to 8.

3. 2. The active energy ray-curable liquid composition according to claim 1, wherein, in the general formula (1), R1 is a saturated hydrocarbon group, and R1 and R2 are bonded to each other to form a 5-membered or 6-membered aliphatic heterocycle.

4. 4. The active energy ray-curable liquid composition according to claim 3, wherein, in the general formula (1), the total number of carbon atoms in the saturated hydrocarbon group directly bonded to the nitrogen atom of the (meth)acrylamide structure is 4 to 10.

5. 2. The active energy ray-curable liquid composition according to claim 1, wherein, in said general formula (1), the saturated hydrocarbon group represented by R1 and R2 has a total of 5 to 20 carbon atoms.

6. The active energy ray-curable liquid composition according to claim 1, wherein in the general formula (1), the total number of carbon atoms of the saturated hydrocarbon groups represented by R1 and R2 is 7 or more.

7. The active energy ray-curable liquid composition according to claim 1 , further comprising a polyfunctional polymerizable monomer.

8. 2. The active energy ray-curable liquid composition according to claim 1, wherein the content of the water is 30 mass % or more based on the total amount of the active energy ray-curable liquid composition.

9. 8. The active energy ray-curable liquid composition according to claim 7, wherein a ratio of the monofunctional polymerizable monomer to a total amount of the polymerizable monomers contained in the active energy ray-curable liquid composition is 10% by mass to 90% by mass.

10. An active energy ray-curable liquid composition as described in claim 1, further containing an active energy ray polymerization initiator.

11. The active energy ray-curable liquid composition according to any one of claims 1 to 10, which is an aqueous ink.

12. an ink applying step of applying an aqueous ink containing an active energy ray-curable liquid composition onto a recording medium; an active energy ray irradiation step of irradiating the aqueous ink applied onto the recording medium with active energy rays; A recording method comprising: a recording method, characterized in that the active energy ray-curable liquid composition contains water and a curable substance and is curable by active energy rays, and the curable substance contains a monofunctional polymerizable monomer having a structure represented by the following general formula (1): 【Chemistry 2】 (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group having at least one of a hydroxyl group and an amide bond and which may contain a heteroatom, and R3 represents a hydrogen atom or a methyl group, and when R1 is a saturated hydrocarbon group, R1 and R2 may be bonded to form an aliphatic heterocycle together with the nitrogen atom which they substitute, and the total number of carbon atoms of the saturated hydrocarbon group represented by R1 and R2 is 5 or more.)

13. The recording method according to claim 12, wherein the ink applying step is carried out by an inkjet recording method.

14. an ink applying device that applies an aqueous ink containing an active energy ray-curable liquid composition onto a recording medium; an active energy ray irradiation device that irradiates the aqueous ink applied onto the recording medium with active energy rays; A recording device having a recording device, characterized in that the active energy ray-curable liquid composition contains water and a curable substance, is curable by active energy rays, and the curable substance contains a monofunctional polymerizable monomer having a structure represented by the following general formula (1): 【Chemistry 3】 (In general formula (1), R1 represents a hydrogen atom or a saturated hydrocarbon group, R2 represents a saturated hydrocarbon group having at least one of a hydroxyl group and an amide bond and which may contain a heteroatom, and R3 represents a hydrogen atom or a methyl group, and when R1 is a saturated hydrocarbon group, R1 and R2 may be bonded to form an aliphatic heterocycle together with the nitrogen atom which they substitute, and the total number of carbon atoms of the saturated hydrocarbon group represented by R1 and R2 is 5 or more.)

15. 15. The recording apparatus according to claim 14, wherein the ink applying device comprises a recording head that ejects ink by an inkjet recording method.

Images