Image forming apparatus and image forming method

Abstract

To provide an image forming apparatus capable of forming an image excellent in beading quality, abrasion resistance and hardness.SOLUTION: The image forming apparatus includes: first discharge means 50 for discharging a first active energy ray-curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acrylic group and a polymerization initiator (C) to a medium; irradiation means 51 for irradiating the first active energy ray-curable composition (1) discharged to the medium with active energy rays; and second discharge means 52 for discharging an ink (2) containing a coloring material, a water-soluble organic solvent, and water onto the first active energy ray-curable composition (1) irradiated with the active energy rays.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an image forming apparatus and an image forming method. [Background technology]

[0002] 2. Description of the Related Art Image forming apparatuses using the inkjet recording method have become increasingly popular in recent years because they are capable of recording color images on plain paper and have low running costs.

[0003] However, conventional techniques are prone to image defects such as character bleeding (hereinafter referred to as "feathering") depending on the combination of ink and recording medium. In addition, when combined with water-based inks, there is a problem of significant degradation of image quality, such as degradation of beading quality on offset printing paper, which has extremely poor absorbency of water-based inks, and on non-absorbent polyethylene terephthalate (PET) films.

[0004] Furthermore, when recording a color image by the inkjet recording method, different color inks are layered one on top of the other, which can cause the color inks to bleed or mix at the color boundary areas (hereinafter referred to as color bleed), resulting in a significant decrease in image quality.

[0005] In order to solve these problems and improve image quality, image forming methods using treatment liquid and ink have been proposed. For example, in order to apply the treatment liquid uniformly, methods have been considered in which the treatment liquid is ejected from a head, sprayed using air pressure, and applied uniformly by controlling the pressure between an application roller and a counter roller.

[0006] Furthermore, with regard to the processing liquid used in the post-processing of ink printing, there is a process consisting of a pre-processing step, a printing step, and a post-processing step, and in particular, there are methods being considered in which a UV varnish is sprayed in the post-processing step (see Patent Document 1), and in which an overcoat liquid containing a resin is coated on the image forming area after printing to impart image abrasion resistance (see Patent Documents 2 and 3). However, the method of Patent Document 1 mentioned above has problems such as the large size of the device, the high cost, and the safety of the materials.Furthermore, the methods of Patent Documents 2 and 3 have problems such as the need to ensure the ejection stability of the overcoat liquid containing the resin from the head, and the high cost of materials such as the resin, and the abrasion resistance of the printed matter on offset printing paper using water-based ink is still insufficient.

[0007] As for the treatment liquid used in the pre-process of ink printing, Patent Document 4 discloses an image forming apparatus that uses a first liquid and a second liquid containing a coloring material, as an image forming apparatus that can quickly cure and fix ink droplets deposited on a recording medium while preventing landing interference, bleeding, etc. One of the first liquid and the second liquid contains a radiation-curable polymerizable compound, and the other contains a curing initiator, and the second liquid is discharged onto an area onto which the first liquid has been discharged, and radiation is applied from the back side of the recording surface of the recording medium that transmits radiation. The first liquid contains a polymer having an amino group, a polymer having an onium group, a polymer having a nitrogen-containing heterocycle, and a diffusion inhibitor such as a metal compound. However, oil-based ink is disclosed as the second liquid, and the problems that arise when using water-based ink are not taken into consideration.

[0008] Patent Document 5 discloses an ink-media set having an ink containing a specific amount of a colorant and a water-dispersible resin, a recording medium having a coating layer, and a pretreatment liquid containing a specific amount of an ink fixing aid and having a specific viscosity. However, the ink fixing aid contained in the pretreatment liquid is an "ink fixing aid that reduces at least one of the dispersibility and solubility of the ink" and is involved in the fixability, and the improvement in fixability by the pretreatment liquid is considered to be auxiliary. There is no description of active energy ray-curable monomers and oligomers in the pretreatment liquid, and sufficient hardness is not obtained.

[0009] Furthermore, Patent Document 6 discloses a liquid composition that is applied to a recording medium together with an anionic or cationic ink containing a colorant and is used to form a colored part on the recording medium, as a treatment liquid that can be used in a pre-process and / or post-process of ink printing. The liquid composition contains dispersed fine particles whose surfaces are charged with an opposite polarity to that of the ink, and also contains a polymerizable component that is converted into a polymer by the application of energy, and a solvent that dissolves the polymerizable component. However, although the liquid composition contains a polymerizable component that is added to a polymer by the application of energy, the fixability is compensated for by fine particles whose surfaces are charged with an opposite polarity to the ink, and the beading quality on offset printing paper is still insufficient. Summary of the Invention [Problem to be solved by the invention]

[0010] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide an image forming apparatus capable of forming an image having excellent beading quality, abrasion resistance and hardness. [Means for solving the problem]

[0011] In order to solve the above problems, the image forming apparatus of the present invention comprises a first ejection means for ejecting a first active energy ray curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C) onto a medium, an irradiation means for irradiating the first active energy ray curable composition (1) ejected onto the medium with active energy rays, and a second ejection means for ejecting an ink (2) containing a colorant, a water-soluble organic solvent and water onto the first active energy ray curable composition (1) irradiated with the active energy rays. The (meth)acrylamide compound (A) having a (meth)acryl group includes an acrylamide compound (A1) represented by the following general formula (1) or the following general formula (2): It is characterized by: General formula (1) and general formula (2) are shown in the mode for carrying out the invention. Effect of the Invention

[0012] According to the present invention, it is possible to provide an image forming apparatus capable of forming an image having excellent beading quality, abrasion resistance and hardness. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a schematic diagram illustrating an example of an image forming apparatus according to the present invention. [Diagram 2] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. [Diagram 3] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. [Figure 4] FIG. 2 is a schematic diagram showing an example of an irradiation means. [Diagram 5] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. [Figure 6] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. [Figure 7] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. [Figure 8] FIG. 4 is a schematic diagram showing another example of an image forming apparatus according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The image forming apparatus and the image forming method according to the present invention will be described below with reference to the drawings. Note that the present invention is not limited to the following embodiment, and may be modified within the scope of what a person skilled in the art can imagine, such as other embodiments, additions, modifications, deletions, etc., and any aspect is within the scope of the present invention as long as it provides the functions and effects of the present invention.

[0015] (First embodiment) The image forming apparatus of the present embodiment is characterized by having a first ejection means for ejecting a first active energy ray curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C) onto a medium, an irradiation means for irradiating the first active energy ray curable composition (1) ejected onto the medium with active energy rays, and a second ejection means for ejecting an ink (2) containing a colorant, a water-soluble organic solvent, and water onto the first active energy ray curable composition (1) irradiated with the active energy rays.

[0016] The image forming method of the present embodiment is characterized by comprising a first discharge step of discharging a first active energy ray-curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C) onto a medium, an irradiation step of irradiating the first active energy ray-curable composition (1) discharged onto the medium with active energy rays, and a second discharge step of discharging an ink (2) containing a colorant, a water-soluble organic solvent, and water onto the first active energy ray-curable composition (1) irradiated with the active energy rays.

[0017] The image formed by the image forming apparatus or the image forming method of the present embodiment is not particularly limited, and may be, for example, a two-dimensional or three-dimensional image. Hereinafter, the image forming apparatus may be referred to as a two-dimensional or three-dimensional image forming apparatus, and the image forming method may be referred to as a two-dimensional or three-dimensional image forming method.

[0018] The image forming apparatus of this embodiment has a transport means for transporting the medium, and the first ejection means, the irradiation means, and the second ejection means are arranged in this order from upstream to downstream in the transport direction of the medium.

[0019] Conventionally, oil-based inks have been used for non-absorbent media such as offset printing paper and PET film, but in recent years, there have been many restrictions on their use due to resource conservation and safety considerations. In addition, from the perspective of energy conservation, there is a shift to printing using water-based inks, and the market is showing a trend toward on-demand printing using inkjet processes, especially for small-lot printing. Non-absorbent media such as general-purpose offset printing paper and PET film are designed to be compatible with oil-based inks, and when water-based inks are used, the ink does not wet and spread evenly, causing severe bleeding, and in high-speed one-pass printing, there are major problems, particularly in the deterioration of beading quality, and the drying and fixation of images immediately after printing.

[0020] According to the present invention, an image excellent in beading quality, abrasion resistance, and hardness can be formed. Furthermore, when inkjet recording is performed on a medium, when recording on offset printing paper using a water-based ink, and even when performing high-speed one-pass printing with a high-speed inkjet printer, an image excellent in beading quality, abrasion resistance, and hardness can be formed.

[0021] <First Discharge Means and First Discharge Step> The first discharge means discharges the first active energy ray-curable composition (1) onto a medium. As the first discharge means, for example, an inkjet head is used. The first discharging step is a step of discharging the first active energy ray-curable composition (1) onto a medium.

[0022] <<First active energy ray-curable composition (1)>> The first active energy ray-curable composition (1) contains a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C), and may contain a polyfunctional polymerizable compound or polymerizable oligomer (B), a hydrogen donor (D), etc., as necessary, and may further contain other components.

[0023] The first active energy ray-curable composition (1) may be referred to as an active energy ray-curable pretreatment liquid or an active energy ray-curable base coat liquid. Hereinafter, the first active energy ray-curable composition (1) may be simply referred to as composition (1), or may be referred to as a pretreatment liquid or a base coat liquid.

[0024] -(Meth)acrylamide compound (A) having a (meth)acryl group- In this embodiment, the (meth)acrylamide compound (A) having a (meth)acryl group refers to a (meth)acrylamide compound having a function of initiating a polymerization reaction and curing by an initiating species such as a radical generated from a polymerization initiator described later. Hereinafter, the (meth)acrylamide compound (A) having a (meth)acryl group may be simply referred to as the (meth)acrylamide compound (A).

[0025] Examples of the (meth)acrylamide compound (A) include N-acryloylmorpholine, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, diisopropyl(meth)acrylamide, diacetone(meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-(hydroxymethyl)(meth)acrylamide, N-(butoxymethyl)(meth)acrylamide, N-[3-(dimethylamino)propyl](meth)acrylamide, N-(1,1-dimethyl-3-oxobutyl)(meth)acrylamide, and 2-(meth)acrylamide-2-methylpropanesulfonic acid. Commercially available products may also be used.

[0026] The molecular weight of the (meth)acrylamide compound (A) is preferably 150 or more and 250 or less. When the molecular weight is 150 or more, odor caused by volatilization of the compound can be suppressed and the stability of inkjet ejection can be improved, which is preferable. When the molecular weight is 250 or less, the curability of the composition is excellent, the strength of the cured product is improved, and further, the viscosity of the composition is not increased, which is preferable.

[0027] As the (meth)acrylamide compound (A) having a (meth)acryl group, it is preferable to include a compound having an acrylamide group and an ester structure having neutrality and moderate polarity. When the (meth)acrylamide compound (A) contains an ester structure having neutrality and moderate polarity, the effects of the present invention are improved.

[0028] A (meth)acrylamide compound having a (meth)acryl group and an ester structure is also referred to as a (meth)acrylic acid ester. In this specification, the term "(meth)acrylic acid ester" refers to an acrylic acid ester or a methacrylic acid ester. The term "(meth)acrylate" refers to an acrylate or a methacrylate.

[0029] The (meth)acrylamide compound (A) having a (meth)acryl group preferably contains an acrylamide compound (A1) represented by the following general formula (1) or the following general formula (2). In this case, the curability and adhesion can be improved. Hereinafter, the acrylamide compound (A1) represented by the following general formula (1) or the following general formula (2) may be simply referred to as the acrylamide compound (A1).

[0030] [ka]

[0031] (In the above general formula (1), R 1 represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms; R 2 represents a linear or branched alkylene group having 1 to 4 carbon atoms; R 3 represents a linear or branched alkyl group having 1 to 4 carbon atoms. 1 , R 2 and R 3 The total number of carbon atoms is 2 to 6.)

[0032] [ka]

[0033] (In the above general formula (2), ring X represents a ring structure containing a nitrogen atom and having 2 to 5 carbon atoms; R 4 represents a single bond or a linear or branched alkylene group having 1 to 3 carbon atoms; R 5 represents a linear or branched alkyl group having 1 to 3 carbon atoms. 4 and R 5 The total number of carbon atoms is 3 to 6.)

[0034] Suitable examples of the acrylamide compound (A1) include N-acryloyl-N-alkylamino acid alkyl esters (including N-acryloylproline alkyl esters) and N-acryloylpiperidine carboxylic acid alkyl esters.

[0035] The alkyl group referred to here means a straight-chain or branched alkyl group having 1 to 4 carbon atoms, and particularly preferred are alkyl groups having 1 or 2 carbon atoms (that is, a methyl group or an ethyl group).

[0036] The N-acryloyl-N-alkylamino acid alkyl ester is not particularly limited and can be appropriately selected according to the purpose. For example, N-acryloyl-N-methylglycine methyl ester, N-acryloyl-N-methylglycine ethyl ester, N-acryloyl-N-methylglycine propyl ester, N-acryloyl-N-methylglycine butyl ester, N-acryloyl-N-ethylglycine methyl ester, N-acryloyl-N-ethylglycine ethyl ester, N-acryloyl-N-ethylglycine propyl ester, N-acryloyl-N-propylglycine methyl ester, N-acryloyl-N-propylglycine ethyl ester, N-acryloyl-N-butylglycine methyl ester, N-acryloyl-N-methylalanine methyl ester, N-acryloyl-N-methyl Examples of the acryloyl-N-methylalanine ethyl ester include N-acryloyl-N-methylalanine propyl ester, N-acryloyl-N-ethylalanine methyl ester, N-acryloyl-N-ethylalanine ethyl ester, N-acryloyl-N-propylalanine methyl ester, N-acryloyl-N-methyl-β-alanine methyl ester, N-acryloyl-N-methyl-β-alanine ethyl ester, N-acryloyl-N-ethyl-β-alanine methyl ester, N-acryloyl-N-ethyl-β-alanine ethyl ester, N-acryloyl-N-methylvaline methyl ester, N-acryloylproline methyl ester, and N-acryloylproline ethyl ester. These may be used alone or in combination of two or more.

[0037] The above-mentioned N-acryloylpiperidine carboxylate alkyl ester is not particularly limited and can be appropriately selected according to purpose. For example, N-acryloylpiperidine-2-carboxylate methyl, N-acryloylpiperidine-3-carboxylate methyl, N-acryloylpiperidine-4-carboxylate methyl, etc. can be mentioned. These can be used alone or in combination of two or more.

[0038] For application to inkjet recording systems, the (meth)acrylamide compound (A) is preferably a colorless, transparent or pale yellow, transparent liquid with low viscosity (100 mPa·s or less) at room temperature (25°C). For the safety of users, it is also preferable that the compound is not strongly acidic or basic and does not contain harmful formaldehyde as an impurity.

[0039] The content of the (meth)acrylamide compound (A) is preferably from 10% by mass to 80% by mass, more preferably from 20% by mass to 70% by mass, and even more preferably from 30% by mass to 60% by mass, based on the total amount of the composition (1).

[0040] The content of the acrylamide compound (A1) in the (meth)acrylamide compound (A) is preferably 10% by mass or more, and more preferably 20% by mass or more. The (meth)acrylamide compound (A) may entirely consist of the acrylamide compound (A1).

[0041] In the composition (1), the mass ratio of the content of the acrylamide compound (A1) to the content of the polymerization initiator (C) is preferably 5 or more and 25 or less, more preferably 8 or more and 20 or less, and even more preferably 9 or more and 19 or less.

[0042] The viscosity of the (meth)acrylamide compound (A) is not particularly limited and can be appropriately selected depending on the purpose. Assuming that the composition (1) is discharged from an inkjet head, the viscosity is preferably 10 to 300 mPa·s at 23°C, more preferably 10 to 200 mPa·s, and even more preferably 10 to 20 mPa·s. If the viscosity is less than 10 mPa·s, dripping from the discharge means may occur, and if it exceeds 300 mPa·s, transfer to the medium may become non-uniform.

[0043] -Polyfunctional polymerizable compound or polymerizable oligomer (B)- The composition (1) preferably contains a multifunctional polymerizable compound or polymerizable oligomer (B). The multifunctional polymerizable compound or polymerizable oligomer (B) is not particularly limited as long as it can undergo a polymerization reaction by active energy rays (ultraviolet rays, electron beams, etc.), and can be appropriately selected according to the purpose. It can be appropriately selected from the viewpoint of adjusting the reaction rate, ink properties, and cured film properties, and may be used alone or in combination of two or more kinds.

[0044] Examples of the polyfunctional polymerizable compound or polymerizable oligomer (B) include radically polymerizable compounds and polymerizable oligomers. Examples of the radically polymerizable polymerizable compound include (meth)acrylate compounds, urethane acrylates, polyester acrylates, etc. These may be used alone or in combination of two or more. In this specification, (meth)acrylate means at least one of acrylate and methacrylate, and (meth)acrylic means at least one of acrylic and methacrylic.

[0045] Examples of the (meth)acrylate compound include difunctional (meth)acrylates, trifunctional (meth)acrylates, tetrafunctional (meth)acrylates, pentafunctional (meth)acrylates, hexafunctional (meth)acrylates, etc. These may be used alone or in combination of two or more.

[0046] Examples of the bifunctional (meth)acrylate include 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2,4-dimethyl-1,5-pentanediol di(meth)acrylate, butylethylpropanediol (meth)acrylate, ethoxylated cyclohexanemethanol di(meth)acrylate, 2-ethyl-2-butyl-butanediol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, bisphenol F polyethoxy di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 2-ethyl-2-butylpropanediol di(meth)acrylate, 1,9-nonanedi(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, and tricyclodecane di(meth)acrylate. These may be used alone or in combination of two or more.

[0047] Examples of the trifunctional (meth)acrylate include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, alkylene oxide-modified tri(meth)acrylate of trimethylolpropane, pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, trimethylolpropane tri((meth)acryloyloxypropyl)ether, alkylene oxide-modified tri(meth)acrylate of isocyanuric acid, dipentaerythritol propionate tri(meth)acrylate, tri((meth)acryloyloxyethyl)isocyanurate, hydroxypivalaldehyde-modified dimethylolpropane tri(meth)acrylate, sorbitol tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, and ethoxylated glycerin tri(meth)acrylate. These may be used alone or in combination of two or more.

[0048] Examples of the tetrafunctional (meth)acrylate include sorbitol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol propionate tetra(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0049] The pentafunctional (meth)acrylate may, for example, be sorbitol penta(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0050] Examples of the hexafunctional (meth)acrylate include dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, alkylene oxide-modified hexa(meth)acrylate of phosphazene, caprolactone-modified dipentaerythritol hexa(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0051] The polymerizable oligomer preferably has one or more ethylenically unsaturated double bonds. The oligomer means a polymer having 2 to 20 repeating monomer structural units.

[0052] The weight average molecular weight of the polymerizable oligomer is not particularly limited and can be appropriately selected depending on the purpose, and is preferably from 1,000 to 30,000, and more preferably from 5,000 to 20,000, in terms of polystyrene. The weight average molecular weight can be measured, for example, by gel permeation chromatography (GPC).

[0053] Examples of the polymerizable oligomer include urethane acrylate oligomers (e.g., aromatic urethane acrylate oligomers, aliphatic urethane acrylate oligomers, etc.), epoxy acrylate oligomers, polyester acrylate oligomers, and other special oligomers. These may be used alone or in combination of two or more.

[0054] Among these, oligomers having 2 to 5 unsaturated carbon-carbon bonds are preferred, and oligomers having 2 unsaturated carbon-carbon bonds are more preferred. When the number of unsaturated carbon-carbon bonds is 2 to 5, good curability can be obtained.

[0055] The amount of the urethane acrylate oligomer is preferably 5% by weight or less based on the total amount of the composition (1) in order to suppress the viscosity.

[0056] As the polymerizable oligomer, a commercially available product can be used. Examples of the commercially available product include UV-2000B, UV-2750B, UV-3000B, UV-3010B, UV-3200B, UV-3300B, UV-3700B, UV-6640B, UV-8630B, UV-7000B, UV-7610B, UV-1700B, UV-7630B, UV-6300B, UV-6640B, UV-7550B, UV-7600B, UV-7605B, UV-7610B, and UV- 7630B, UV-7640B, UV-7650B, UT-5449, UT-5454; Sartomer's CN902, CN902J75, CN929, CN940, CN944, CN944B85, CN959, CN961E75, CN961H81, CN962, CN963, CN963A80, CN963B80, CN963E75, CN963E80, CN963J85, CN964, CN965, CN965A80, CN966, CN966A80, CN966B85, CN966H90, CN966J 75, CN968, CN969, CN970, CN970A60, CN970E60, CN971, CN971A80, CN971J75, CN972, CN973, CN973A80, CN973H85, CN973J75, CN975, CN977, C N977C70, CN978, CN980, CN981, CN981A75, CN981B88, CN982, CN982A75, CN982B88, CN982E75, CN983, CN984, CN985, CN985B88, CN986, CN989, CN991, CN992, CN994, CN996, CN997, CN999, CN9001, CN9002, CN9004, CN9005, CN9006, CN9007, CN9008, CN9009, CN9010, CN9011, CN9013, CN9 018, CN9019, CN9024, CN9025, CN9026, CN9028, CN9029, CN9030, CN9060, CN9165, CN9167, CN9178, CN9290, CN9782, CN9783, CN9788, CN9893;Examples of such compounds include EBECRYL210, EBECRYL220, EBECRYL230, EBECRYL270, KRM8200, EBECRYL4666, EBECRYL5129, EBECRYL8210, EBECRYL8301, EBECRYL8804, EBECRYL8807, EBECRYL9260, KRM7735, KRM8296, KRM8452, EBECRYL4858, EBECRYL8402, EBECRYL9270, EBECRYL8311, and EBECRYL8701 manufactured by Daicel-Cytec Co., Ltd. These compounds may be used alone or in combination of two or more kinds.

[0057] Moreover, instead of a commercially available product, a synthetic product obtained by synthesis may be used, or a synthetic product and a commercially available product may be used in combination.

[0058] The content of the polyfunctional polymerizable compound or polymerizable oligomer (B) in the composition (1) is preferably from 1% by mass to 70% by mass, and more preferably from 10% by mass to 50% by mass.

[0059] -Polymerization initiator (C)- The polymerization initiator (C) is not particularly limited and can be appropriately selected depending on the purpose. For example, benzophenone, acetophenone, 2-hydroxy-2-phenylacetophenone, 2-ethoxy-2-phenylacetophenone, 2-methoxy-2-phenylacetophenone, 2-isopropoxy-2-phenylacetophenone, 2-isobutoxy-2-phenylacetophenone, 4-methoxyacetophenone, 4-benzyloxyacetophenone, 4-phenylacetophenone, 4-benzoyl-4'-methyldiphenyl sulfide, methyl benzoylformate, ethyl benzoylformate, 2-hydroxy-1-(4-isopropenylphenyl)-2-methylpropan-1-one oligomer [benzene, (1-methylethynyl)-, homopolymer, ar-(2-hydroxy-2-methyl-1-oxopropyl) derivative] (manufactured by IGM, "Esacure ONE"), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (trade name "Irgacure 369"), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (trade name "Irgacure 819"), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (trade name "Irgacure TPO"), polyethylene glycol 200-di(β-4(4-(2-dimethylamino-2-benzyl)butanoylphenyl)piperazine) (manufactured by IGM, "Omnipol 910"), 1,3-di({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]}oxy)-2,2-bis({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]}oxymethyl)propane (manufactured by Lambson, "Speedcure7010"), and the like. These may be used alone or in combination of two or more.

[0060] The content of the polymerization initiator (C) is preferably from 1 to 20% by mass, more preferably from 3 to 15% by mass, and even more preferably from 5 to 10% by mass, based on the total amount of the composition (1).

[0061] -Hydrogen donor (D)- The hydrogen donor (D) is a compound capable of donating hydrogen to the polymerization initiator (C), and examples thereof include compounds capable of donating hydrogen to a radical polymerization initiator such as a compound having a benzophenone skeleton excited by light irradiation.

[0062] The compound having a benzophenone skeleton or the like as the radical polymerization initiator is a substance in which polymerization is initiated by the polymerization initiation mechanism shown below. That is, the compound having a benzophenone skeleton or the like is excited by light irradiation. Then, the excited molecule extracts hydrogen from a nearby compound, and a radical is generated on the compound from which hydrogen has been extracted, which becomes the radical polymerization initiation point. As a result, the compound having a benzophenone skeleton or the like acts as a photoradical polymerization initiator. That is, if a compound that can extract hydrogen exists together with the compound having a benzophenone skeleton or the like, polymerization is initiated by the above polymerization initiation mechanism. Therefore, for example, if hydrogen is extracted from the radical polymerizable compound used in this embodiment, polymerization may be initiated from there.

[0063] The hydrogen donor (D) smoothly transfers hydrogen to a compound molecule having a benzophenone skeleton excited by light irradiation, and can efficiently advance polymerization. Therefore, by adding the hydrogen donor (D) to the polymerization initiator (C), polymerization reactivity can be significantly improved while maintaining low yellowing.

[0064] The hydrogen donor (D) may be, for example, a compound capable of smoothly donating hydrogen to a compound molecule having a benzophenone skeleton excited by irradiation with light. Examples of the hydrogen donor (D) include compounds having an amino group such as diethylamine, diphenylamine, triethylamine, tributylamine, diethanolamine, triethanolamine, N,N-diethylethanolamine, N,N-diethylmethylamine, dipropylamine, N,N-dimethylaniline, ethyl p-diethylaminobenzoate, and ethyl p-dimethylaminobenzoate; compounds having a hydroxyl group such as methanol, ethanol, propanol, isopropyl alcohol, butanol, ethylene glycol, propylene glycol, butanediol, and phenol; tetrahydrofuran, tetrahydropyran, dioxane, trioxane, diethylene glycol, dipropylene glycol, propylene glycol monomethyl ether, and propylene glycol monomethyl ether. Compounds having an ether bond such as glycol monomethyl ether acetate, butanethiol, propanethiol, hexanedithiol, decanedithiol, n-dodecyl mercaptan, dodecyl (4-methylthio)phenyl ether, benzenethiol, 4-dimethylmercaptobenzene, 2-mercaptoethanol, 1-mercapto-2-propanol, 3-mercapto-2-butanol, 3-mercapto-1,2-propanediol, mercaptophenol and other mercapto compounds, or disulfides obtained by oxidizing these compounds, butyl thioglycolate, ethylene glycol bisthioglycolate, ethylene glycol bisthiopropionate, butanediol bis(3-mercaptoisobutyrate), 1,4-butanediol bisthioglycolate, 1,4-butanediol bisthiopropionate, octyl β-mercaptopropionate, methoxybutyl β-mercaptopropionate, trishydroxyethyl tristhiopropionate, trimethylolpropane tris(3-mercaptoisobutyrate), trimethylolpropane tris(3-mercaptobutyrate), trimethylolpropane tris(3-mercaptopropionate), trimethylolpropane tris(β-thiopropionate), trimethylolpropane tristhioglycolate, trimethylolpropane tristhiopropionate, pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakisthioglycolate, pentaerythritol tetrakisthiopropionate, thioglycolic acid, thiosalicylic acid, thiomalic acid, mercaptoacetic acid, 2-mercaptoethanesulfonic acid, 2-Mercaptonicotinic acid, 2-mercaptopropionic acid, 3-mercaptopropanesulfonic acid, 3-mercaptopropionic acid, 3-mercaptobutyric acid, 4-mercaptobutanesulfonic acid, 3-[N-(2-mercaptoethyl)amino]propionic acid, 3-[N-(2-mercaptoethyl)carbamoyl]propionic acid, 2-mercapto-3-pyridinol, 2-mercaptoimidazole, 2-mercaptoethylamine, 2 Examples of the mercapto group-containing compounds include mercaptobenzimidazole, 2-mercaptobenzothiazole, 6-trimercapto-s-triazine, N-(2-mercaptopropionyl)glycine, N-(3-mercaptopropionyl)alanine, diisopropylthioxanthone, diethylthioxanthone, thiophosphites, and trimercaptopropionic acid tris(2-hydroxyethyl)isocyanurate. Other compounds can also be used.

[0065] As the hydrogen donor (D), a compound having an amino group is particularly preferably used in terms of low energy of hydrogen transfer, and among these, methyl 2-(N,N-dimethylamino)benzoate, ethyl 4-(N,N-dimethylamino)benzoate, ethyl 4-(N,N-diethylamino)benzoate, a mixture of 1,3-di({α-4-(dimethylamino)benzoylpoly[oxy(1-methylethylene)]}oxy)-2,2-bis({α-4-(dimethylamino)benzoylpoly[oxy(1-methylethylene)]}oxymethyl)propane and {α-4-(dimethylamino)benzoylpoly(oxyethylene)-poly[oxy(1-methylethylene)]-poly(oxyethylene)}4-(dimethylamino)benzoate (manufactured by Lambson, "Speedcure7040"), and the like are more preferred.

[0066] The content of the hydrogen donor (D) in the composition (1) is preferably 0.1% by mass to 10% by mass, more preferably 5% by mass or less, and more preferably 0.01% by mass to 50% by mass, more preferably 0.1% by mass to 20% by mass, based on the polymerizable compound in the composition (1).

[0067] -Other polymerizable compounds (E)- The composition (1) may contain a polymerizable compound (E) in addition to the (meth)acrylamide compound (A) and the polyfunctional polymerizable compound or polymerizable oligomer (B). The other polymerizable compound (E) is not particularly limited as long as it can undergo a polymerization reaction by active energy rays (ultraviolet rays, electron beams, etc.), and can be appropriately selected according to the purpose. It is appropriately selected from the viewpoint of adjusting the reaction rate, ink properties, and cured film properties, and may be used alone or in combination of two or more types. By using the other polymerizable compound (E) in combination, the curability and viscosity of the composition, and the hardness and adhesion of the cured product can be easily adjusted according to the purpose of use.

[0068] Examples of the other polymerizable compounds (E) include radically polymerizable monofunctional polymerizable compounds. Examples of the radically polymerizable polymerizable compound include monofunctional (meth)acrylate compounds and aromatic vinyl compounds. These may be used alone or in combination of two or more. In this specification, (meth)acrylate means at least one of acrylate and methacrylate, and (meth)acrylic means at least one of acrylic and methacrylic. These may be used alone or in combination of two or more.

[0069] Examples of the monofunctional (meth)acrylate include tetrahydrofurfuryl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, tert-octyl (meth)acrylate, isoamyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, 4-n-butylcyclohexyl (meth)acrylate, bornyl (meth)acrylate, isobornyl (meth)acrylate, and methyl methacrylate. (meth)acrylate, benzyl (meth)acrylate, butoxyethyl (meth)acrylate, 2-chloroethyl (meth)acrylate, 4-bromobutyl (meth)acrylate, cyanoethyl (meth)acrylate, benzyl (meth)acrylate, butoxymethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, alkoxymethyl (meth)acrylate, alkoxyethyl (meth)acrylate, 2-(2-methoxyethoxy)ethyl (meth)acrylate, 2-(2-butoxyethoxy)ethyl (meth)acrylate, 2, 2,2-Tetrafluoroethyl (meth)acrylate, 1H,1H,2H,2H-perfluorodecyl (meth)acrylate, 4-butylphenyl (meth)acrylate, phenyl (meth)acrylate, 2,4,5-tetramethylphenyl (meth)acrylate, 4-chlorophenyl (meth)acrylate, phenoxymethyl (meth)acrylate, phenoxyethyl (meth)acrylate, glycidyl (meth)acrylate, glycidyloxybutyl (meth)acrylate, glycidyloxyethyl (meth)acrylate, glycidyloxypropyl (meth)acrylate, (meth)acrylate, hydroxyalkyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, diethylaminopropyl (meth)acrylate, trimethoxysilylpropyl (meth)acrylate,Trimethylsilylpropyl (meth)acrylate, polyethylene oxide monomethyl ether (meth)acrylate, oligoethylene oxide monomethyl ether (meth)acrylate, polyethylene oxide (meth)acrylate, oligoethylene oxide (meth)acrylate, oligoethylene oxide monoalkyl ether (meth)acrylate, polyethylene oxide monoalkyl ether (meth)acrylate, dipropylene glycol (meth)acrylate, polypropylene oxide monoalkyl ether (meth)acrylate, oligopropylene oxide monoalkyl ether (meth)acrylate, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyhexahydrophthalic acid, 2 -methacryloyloxyethyl-2-hydroxypropyl phthalate, butoxydiethylene glycol (meth)acrylate, trifluoroethyl (meth)acrylate, perfluorooctylethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, ethylene oxide modified phenol (meth)acrylate, ethylene oxide modified cresol (meth)acrylate, ethylene oxide modified nonylphenol (meth)acrylate, propylene oxide modified nonylphenol (meth)acrylate, ethylene oxide modified-2-ethylhexyl (meth)acrylate, 2-(2-vinyloxyethoxy)ethyl acrylate, benzyl acrylate, etc. These may be used alone or in combination of two or more.

[0070] Among these, from the viewpoints of low viscosity, low odor, and high curing property, phenoxyethyl (meth)acrylate, benzyl acrylate, 2-(2-vinyloxyethoxy)ethyl acrylate, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate are preferred, and from the viewpoints of compatibility with photopolymerization initiators and other monomers, phenoxyethyl (meth)acrylate, benzyl acrylate, and 2-(2-vinyloxyethoxy)ethyl acrylate are particularly preferred.

[0071] Among the other polymerizable compounds (E), examples of monofunctional compounds include urethane (meth)acrylate derivatives obtained by reacting a (meth)acrylic acid ester having a hydroxyl group with a compound having an isocyanate group, and epoxy (meth)acrylate derivatives obtained by reacting a compound having an epoxy group with (meth)acrylic acid.

[0072] In addition to derivatives of (meth)acrylic acid, N-vinyl compounds such as N-vinylcaprolactam, N-vinylpyrrolidone, and N-vinylformamide; aromatic vinyl compounds such as styrene and α-methylstyrene; vinyl ethers such as diethylene glycol divinyl ether, triethylene glycol divinyl ether, and cyclohexane dimethanol divinyl ether; and allyl compounds such as allyl glycidyl ether, diallyl phthalate, and triallyl trimellitate can also be used.

[0073] Examples of the aromatic vinyl compounds include styrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, isopropylstyrene, chloromethylstyrene, methoxystyrene, acetoxystyrene, chlorostyrene, dichlorostyrene, bromostyrene, vinyl benzoic acid methyl ester, 3-methylstyrene, 4-methylstyrene, 3-ethylstyrene, 4-ethylstyrene, 3-propylstyrene, 4-propylstyrene, 3-butylstyrene, 4-butylstyrene, 3-hexylstyrene, 4-hexylstyrene, 3-octylstyrene, 4-octylstyrene, 3-(2-ethylhexyl)styrene, 4-(2-ethylhexyl)styrene, allylstyrene, isopropenylstyrene, butenylstyrene, octenylstyrene, 4-t-butoxycarbonylstyrene, 4-methoxystyrene, 4-t-butoxystyrene, etc. These may be used alone or in combination of two or more.

[0074] The other polymerizable compound (E) is contained in the composition (1) in an amount of preferably 1.0% by mass or more and 30% by mass or less, and more preferably 5.0% by mass or more and 20% by mass or less.

[0075] -Further ingredients- Furthermore, in order to exhibit the functionality of the composition (1), various kinds of sensitizers, light stabilizers, surface treatment agents, surfactants, viscosity reducers, antioxidants, age resistors, crosslinking accelerators, polymerization inhibitors, plasticizers, preservatives, pH adjusters, defoamers, moisturizers, dispersants, dyes, etc. may be contained.

[0076] <Irradiation means> The irradiation means irradiates the first active energy ray-curable composition (1) discharged onto the medium with active energy rays.

[0077] The active energy rays are not particularly limited, and may be any rays that can provide the energy required to promote the polymerization reaction of the polymerizable components in the composition, such as ultraviolet rays, electron beams, α rays, β rays, γ rays, and X-rays. In particular, when a high-energy light source is used, the polymerization reaction can be promoted without using a polymerization initiator. In addition, in the case of ultraviolet irradiation, mercury-free irradiation is strongly desired from the viewpoint of environmental protection, and replacement with GaN-based semiconductor ultraviolet light-emitting devices is very useful industrially and environmentally. Furthermore, ultraviolet light-emitting diodes (UV-LEDs) and ultraviolet laser diodes (UV-LDs) are small, have a long life, are highly efficient, and are low cost, making them preferable as ultraviolet light sources.

[0078] The active energy rays are preferably ultraviolet rays having a peak wavelength of 365 nm or more and 405 nm or less. In this case, safety can be improved and energy consumption can be reduced. It is preferable to use UV-LED as a means for irradiating such ultraviolet rays.

[0079] The amount of active energy rays irradiated is 10 mJ / cm 2 More than 500mJ / cm 2 In this case, safety can be improved, energy consumption can be reduced, and the device can be made more compact.

[0080] <Second Discharge Means and Second Discharge Step> The second ejection means ejects the ink (2) onto the first active energy ray curable composition (1) irradiated with active energy rays. As the second ejection means, for example, an inkjet head is used. In particular, it is preferable to use a line head. The ink (2) ejected by the second ejection means may be one type or multiple types. The second ejection step is a step of ejecting the ink (2) onto the first active energy ray-curable composition (1) that has been irradiated with active energy rays.

[0081] <<Ink (2)>> The ink (2) contains a coloring material, a water-soluble organic solvent, and water, and may contain other components as necessary. Since the ink (2) is preferably ejected from an inkjet head, the ink (2) may be referred to as a water-based ink for inkjet recording.

[0082] Since the ink (2) contains the first active energy ray-curable composition (1) and the (meth)acrylamide compound (A) having a highly polar (meth)acryl group, it is resistant to repelling or bleeding regardless of the composition of the aqueous ink, but it is preferable that the sum of the water and the water-soluble organic solvent in the composition is 90% or more and the ratio of water to the water-soluble organic solvent is between 40:60 and 60:40.

[0083] -Coloring materials- The coloring material can be appropriately selected without any particular limitation. For example, a water-insoluble or poorly water-soluble coloring material is used. In this specification, "water-insoluble" or "poorly water-soluble" means that the coloring material does not dissolve in 100 parts by mass of water at 20°C in an amount of 10 parts by mass or more, and "dissolved" means that separation or sedimentation of the coloring material is not observed visually on the surface or underside of the aqueous solution.

[0084] Examples of the coloring material include dyes such as oil-soluble dyes and disperse dyes, pigments, etc. From the viewpoint of good adsorption and encapsulation, oil-soluble dyes and disperse dyes are preferred, but pigments are preferably used from the viewpoint of light resistance of the resulting image.

[0085] Examples of the pigment include organic pigments and inorganic pigments. Examples of black-and-white pigments include carbon blacks (CI Pigment Black 7) such as furnace black, lamp black, acetylene black, and channel black; other pigments include metals such as copper, iron (CI Pigment Black 11), and titanium oxide; and organic pigments such as aniline black (CI Pigment Black 1).

[0086] For color, for example, CI Pigment Yellow 1 (Fast Yellow G), 3, 12 (Disazo Yellow AAA), 13, 14, 17, 24, 34, 35, 37, 42 (Yellow Iron Oxide), 53, 55, 74, 81, 83 (Disazo Yellow HR), 95, 97, 98, 100, 101, 104, 108, 109, 110, 117, 120, 138, 153, CI Pigment Orange 5, 13, 16, 17, 3 6, 43, 51, CI Pigment Red 1, 2, 3, 5, 17, 22 (Brilliant First Scarlet), 23, 31, 38, 48:2 (Permanent Red B (Ba)), 48:2 (Permanent Red 2B (Ca)), 48:3 (Permanent Red 2B (Sr)), 48:4 (Permanent Red 2B (Mn)), 49:1, 52:2, 53:1, 57:1 (Brilliant Carmine 6B), 60:1 , 63:1, 63:2, 64:1, 81 (Rhodamine 6G Lake), 83, 88, 101 (Red oxide), 104, 105, 106, 108 (Cadmium Red), 112, 114, 122 (Quinacridone Magenta), 123, 146, 149, 166, 168, 170, 172, 177, 178, 179, 185, 190, 193, 209, 219, CI Pigment Violet 1 (Rhodamine Lake), 3, 5: 1, 16, 19 (Quinacridone Red), 23, 38, CI Pigment Blue 1, 2, 15 (Phthalocyanine Blue R), 15:1, 15:2, 15:3 (Phthalocyanine Blue G), 15:4, 15:6 (Phthalocyanine Blue E), 16, 17:127 (Prussian Blue), 28 (Cobalt Blue), 29 (Ultraviolet Blue), 56, 60, 63, CI Pigment Green 1, 4, 7, 8, 10, 17, 18, 36, etc. Carboxylic acid modified pigments are preferably used as the pigment.

[0087] The content of the coloring material in the ink (2) is preferably from 1 to 20% by mass, more preferably from 3 to 12% by mass, and particularly preferably from 5 to 10% by mass.

[0088] -Water-soluble organic solvent- The water-soluble organic solvent is not particularly limited, and for example, various materials that are conventionally used in ink jet recording inks can be used.

[0089] Examples of water-soluble organic solvents include hydroxy compounds such as 2-methyl-1,3-propanediol, 3-methyl-1,3-butanediol, 3-methyl-1,5-pentanediol, 2-ethyl-1,3-hexanediol, glycerin, 1,3-butanediol, triethylene glycol, 1,6-hexanediol, propylene glycol, 1,5-pentanediol, diethylene glycol, dipropylene glycol, trimethylolpropane, trimethylolethane, ethylene glycol, 1,3-propanediol, 1,4-butanediol, 2,3-butanediol, tripropylene glycol, tetraethylene glycol, hexylene glycol, polyethylene glycol, polypropylene glycol, 1,2,6-hexanetriol, 1,2,4-butanetriol, 1,2,3-butanetriol, thiodiglycol, and pentaerythritol; and ethylene glycol monoethyl. Examples of the water-soluble organic solvent include polyhydric alcohol alkyl ethers such as ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, tetraethylene glycol monomethyl ether, and propylene glycol monoethyl ether; polyhydric alcohol aryl ethers such as ethylene glycol monophenyl ether and ethylene glycol monobenzyl ether; nitrogen-containing heterocyclic compounds (lactams) such as 2-pyrrolidone, N-methyl-2-pyrrolidone, N-hydroxyethyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, ε-caprolactam, and γ-butyrolactone; amides such as formamide, N-methylformamide, and N,N-dimethylformamide; sulfur-containing compounds such as dimethyl sulfoxide, sulfolane, and thiodiethanol; propylene carbonate, and ethylene carbonate. The water-soluble organic solvent may be used alone or in combination. The water-soluble organic solvent is not limited to these.

[0090] The content of the water-soluble organic solvent in the ink (2) is preferably 10 to 50% by mass.

[0091] -water- The water is not particularly limited and can be appropriately selected, but so-called ion-exchanged water (resistivity of 10.0 MΩ or more) is preferable.

[0092] The water content in ink (2) is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoints of the drying property and ejection reliability of the ink, however, it is preferably from 10% by mass to 90% by mass, and more preferably from 30% by mass to 80% by mass.

[0093] -Other ingredients- Other components include, for example, surfactants. There are no particular limitations on the surfactants, but they can be appropriately selected from surfactants that do not impair dispersion stability depending on the type of colorant and the combination of wetting agents, penetrants, etc., according to the purpose. In particular, when printing on printing paper, surfactants with low surface tension and high leveling are preferred, and at least one selected from silicone-based surfactants and fluorine-based surfactants are suitable. Among these, fluorine-based surfactants are particularly preferred.

[0094] As the fluorine-based surfactant, for example, perfluoroalkyl sulfonic acid compounds, perfluoroalkyl carboxylic acid compounds, perfluoroalkyl phosphate compounds, perfluoroalkyl ethylene oxide adducts, and polyoxyalkylene ether polymer compounds having perfluoroalkyl ether groups on the side chains are particularly preferred because they have little foaming properties.

[0095] Examples of the perfluoroalkylsulfonic acid compound include perfluoroalkylsulfonic acid and perfluoroalkylsulfonate salts. Examples of the perfluoroalkyl carboxylic acid compound include perfluoroalkyl carboxylic acids and perfluoroalkyl carboxylates. Examples of the perfluoroalkyl phosphate compound include perfluoroalkyl phosphate and salts of perfluoroalkyl phosphate. Examples of the polyoxyalkylene ether polymer compound having a perfluoroalkyl ether group on the side chain include sulfate ester salts of polyoxyalkylene ether polymers having a perfluoroalkyl ether group on the side chain, and salts of polyoxyalkylene ether polymers having a perfluoroalkyl ether group on the side chain.

[0096] Examples of counter ions of the salts in these fluorosurfactants include Li, Na, K, NH4, NH3CH2CH2OH, NH2(CH2CH2OH)2, and NH(CH2CH2OH)3.

[0097] The fluorine-based surfactant may be appropriately selected or may be a commercially available product. Examples of the commercially available products include Surflon series (S-111, S-112, S-113, S-121, S-131, S-132, S-141, S-145) manufactured by Asahi Glass Co., Ltd., Fullard series (FC-93, FC-95, FC-98, FC-129, FC-135, FC-170C, FC-430, FC-431) manufactured by Sumitomo 3M Co., Ltd., Megafac series (F-470, F-1405, F-474) manufactured by Dainippon Ink Co., Ltd., Zonyl (F-470, F-4705, F-474) manufactured by Dupont Co., Ltd., and Zonyl (F-470, F-4705, F-474) manufactured by Dupont Co., Ltd. Examples of such inks include TBS, FSP, FSA, FSN-100, FSN, FSO-100, FSO, FS-300, and UR manufactured by Neos Co., Ltd., FT-110, FT-250, FT-252, FT-400S, FT-150, and FT-400SW manufactured by Neos Co., Ltd., and PF-151N manufactured by OmNova Co., Ltd. Among these, FT-110, FT-250, FT-251, FT-400S, FT-150, and FT-400SW manufactured by Neos Co., Ltd., and PF-151N manufactured by OmNova Co., Ltd. are particularly preferred from the viewpoint of achieving good printing quality, particularly improved color development and uniform dyeing on paper.

[0098] Silicone surfactant is not particularly limited and can be appropriately selected according to purpose.Preferably, it is not decomposed even at high pH, ​​for example, side chain modified polydimethylsiloxane, both end modified polydimethylsiloxane, one end modified polydimethylsiloxane, side chain both end modified polydimethylsiloxane, etc. As modified group, it is particularly preferable that it has polyoxyethylene group or polyoxyethylene polyoxypropylene group, because it shows good properties as an aqueous surfactant.

[0099] Such surfactants may be appropriately synthesized or commercially available products, which are readily available from, for example, BYK-Chemie, Shin-Etsu Silicones, and Dow Corning Toray Silicones.

[0100] The polyether-modified silicone surfactant is not particularly limited and can be appropriately selected depending on the purpose. For example, a compound in which a polyalkylene oxide structure is introduced into the Si part side chain of dimethylpolysiloxane can be mentioned. The polyether-modified silicone compound may be a synthetic product or a commercially available product, such as KF-618, KF-642, and KF-643 manufactured by Shin-Etsu Chemical Co., Ltd.

[0101] In addition to the fluorine-based surfactants and silicone-based surfactants, anionic surfactants, nonionic surfactants, amphoteric surfactants, etc. can also be used. Examples of the anionic surfactant include polyoxyethylene alkyl ether acetates, dodecylbenzene sulfonates, succinic acid ester sulfonates, laurates, and polyoxyethylene alkyl ether sulfates. Examples of the nonionic surfactant include acetylene glycol surfactants, polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl esters, and polyoxyethylene sorbitan fatty acid esters.

[0102] Examples of the acetylene glycol surfactant include 2,4,7,9-tetramethyl-5-decyne-4,7-diol, 3,6-dimethyl-4-octyne-3,6-diol, and 3,5-dimethyl-1-hexyne-3-ol. Examples of commercially available acetylene glycol surfactants include the Surfynol series (104, 82, 465, 485, TG) manufactured by Air Products.

[0103] Examples of amphoteric surfactants include laurylaminopropionate, lauryl dimethyl betaine, stearyl dimethyl betaine, lauryl dihydroxyethyl betaine, lauryl dimethylamine oxide, myristyl dimethylamine oxide, stearyl dimethylamine oxide, dihydroethyl lauryl amine oxide, polyoxyethylene coconut oil alkyl dimethylamine oxide, dimethyl alkyl (coconut) betaine, dimethyl lauryl betaine, etc. Commercially available products of such surfactants can be easily obtained from, for example, Nikko Chemicals, Nippon Emulsion, Nippon Shokubai, Toho Kagaku, Kao, Adeka, Lion, Aoki Oil, Sanyo Chemical, etc.

[0104] The surfactant is not limited to these, and may be used alone or in combination. Even if a surfactant does not easily dissolve in the recording ink alone, it can be solubilized by mixing and can exist stably.

[0105] The content of the surfactant in the ink (2) is preferably 0.01% by mass to 3% by mass, and more preferably 0.5% by mass to 2% by mass. However, the total content of liquid components that have a higher boiling point than water and are liquid in the ink at 25°C is 20% by mass or less, and preferably 15% by mass or less. If the content is less than 0.01% by mass, the effect of adding the surfactant may be lost, and if it exceeds 3% by mass, the permeability into the recording medium may be higher than necessary, which may result in a decrease in image density or strike-through.

[0106] Other components include, for example, resin emulsions. Resin emulsions refer to emulsions in which the continuous phase is water and the dispersed phase is a resin component such as the following. Resin emulsions have the property of thickening and agglomeration, suppressing the penetration of coloring components and promoting fixation to recording materials. In addition, some types of resin emulsions form a film on the recording material, improving the abrasion resistance of printed matter.

[0107] Examples of the resin component of the dispersed phase include acrylic resins, vinyl acetate resins, styrene-butadiene resins, vinyl chloride resins, acrylic-styrene resins, butadiene resins, and styrene resins. The resin is preferably a polymer having both a hydrophilic portion and a hydrophobic portion. The particle size of these resin components is not particularly limited as long as they form an emulsion, but is preferably about 150 nm or less, and more preferably about 5 to 100 nm.

[0108] These resin emulsions can be obtained by mixing resin particles, optionally together with a surfactant, in water. For example, an emulsion of an acrylic resin or a styrene-acrylic resin can be obtained by mixing a (meth)acrylic acid ester or styrene, a (meth)acrylic acid ester, optionally a (meth)acrylic acid ester, and a surfactant in water. The mixing ratio of the resin component to the surfactant is usually preferably about 10:1 to 5:1. If the amount of the surfactant used is less than the above range, it is difficult to form an emulsion, and if it exceeds the above range, the water resistance of the ink tends to decrease and the permeability tends to deteriorate, which is not preferable.

[0109] The ratio of the resin and water as the dispersed phase components of the emulsion is suitably in the range of 60 to 400 parts by mass, preferably 100 to 200 parts by mass, per 100 parts by mass of the resin.

[0110] Examples of commercially available resin emulsions include Microgel E-1002, E-5002 (styrene-acrylic resin emulsions, manufactured by Nippon Paint Co., Ltd.), Boncoat 4001 (acrylic resin emulsion, manufactured by Dainippon Ink and Chemicals Co., Ltd.), Boncoat 5454 (styrene-acrylic resin emulsion, manufactured by Dainippon Ink and Chemicals Co., Ltd.), SAE-1014 (styrene-acrylic resin emulsion, manufactured by Zeon Corporation), and Saibinol SK-200 (acrylic resin emulsion, manufactured by Saiden Chemical Co., Ltd.).

[0111] In addition, for example, a pH adjuster may be contained. In the case of kneading and dispersing a colorant in water with a carboxylic acid group as a hydrophilic group in an ink material system, there is a strong tendency for the ink to show acidity. That is, the surface of the pigment particles dispersed in a medium such as water is wrapped with dissociated carboxylic acid groups, and the ink as a whole shows acidity. The dissociation of the carboxylic acid on the particle surface is easily inhibited by a decrease in pH, and when this "inhibition of dissociation of the carboxylic acid" occurs, the dispersed particles aggregate, resulting in poor ejection. In order to prevent this dissociation inhibition, aggregation, and poor ejection, it is preferable to add a pH adjuster to keep the ink alkaline and maintain the stability of the dispersion state and the stability of ejection.

[0112] The pH of ink (2) is preferably 7 or more and less than 11. If the pH is 11 or more, the ink will dissolve a large amount of the material of the inkjet head or ink supply unit, causing problems such as deterioration of the ink, leakage, and ejection defects.

[0113] Ink (2) is preferably prepared by kneading and dispersing the pigment in water together with a suitable surfactant to prepare a kneaded dispersion, and then dispersing the kneaded dispersion in water together with other additives such as a water-soluble organic solvent, a preservative, antifungal agent, and an antirust agent. It is preferable to add the pH adjuster when the pigment is kneaded and dispersed in water together with the surfactant, rather than adding it together with the preservative, antifungal agent, antirust agent, and other additives after the kneading and dispersion. This is because the addition of some pH adjusters may destroy the dispersion.

[0114] Examples of the pH adjuster include alcohol amines, alkali metal hydroxides, ammonium hydroxide, phosphonium hydroxide, and alkali metal carbonates. Examples of the alcohol amines include diethanolamine, triethanolamine, and 2-amino-2-ethyl-1,3-propanediol. Examples of the hydroxides of the alkali metal elements include lithium hydroxide, sodium hydroxide, and potassium hydroxide. Examples of the hydroxide of ammonium include ammonium hydroxide, quaternary ammonium hydroxide, and quaternary phosphonium hydroxide. Examples of the alkali metal carbonate include lithium carbonate, sodium carbonate, and potassium carbonate.

[0115] In addition, the composition may contain, for example, an antiseptic or fungicide, such as sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol, or 1,2-benzoisothiazolin-3-one.

[0116] In addition, the coating may contain, for example, a rust inhibitor, such as acid sulfite, sodium thiosulfate, ammonium thiodiglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, dicyclohexylammonium nitrite, or benzotriazole.

[0117] In addition, for example, a metal ion sequestering agent, a water-soluble ultraviolet absorbing agent, a water-soluble infrared absorbing agent, etc. may be added depending on the purpose.

[0118] -others- From the viewpoint of ejection stability, the viscosity of ink (2) at 23° C. is preferably from 3 to 40 mPa·s, and more preferably from 6 to 20 mPa·s.

[0119] Ink (2) is preferably used in an inkjet recording method having a droplet ejection step, which is inkjet printing using a line head. In an inkjet method using a so-called line head in which the head is fixed, beading can be further suppressed, and abrasion resistance can be improved even in high-speed one-pass printing using a high-speed inkjet printer.

[0120] After the ink (2) is ejected, the ink (2) may be dried by a drying means. Examples of the drying means include hot air heating. When ejecting the second active energy rays by a third ejection means described below, it is preferable to perform drying before ejection by the third ejection means.

[0121] <Third Discharge Means and Third Discharge Step> The image forming apparatus of this embodiment may use a third discharge means for discharging the second active energy ray curable composition (3). When the third discharge means is used, it is preferable to further use an irradiation means for irradiating the second active energy ray curable composition (3) with active energy rays. In order to distinguish it from the irradiation means for irradiating the composition (1) with active energy rays, the irradiation means for irradiating the second active energy ray curable composition (3) with active energy rays is also referred to as a downstream irradiation means.

[0122] The third ejection step is a step of ejecting the second active energy ray curable composition (3) onto the ink (2) after the second ejection step. It is preferable to have an irradiation step of irradiating the second active energy ray curable composition (3) with active energy rays after the third ejection step.

[0123] The abrasion resistance can be improved by using a third ejection means for ejecting the second active energy ray-curable composition (3) and further irradiating the second active energy ray-curable composition (3) with active energy rays to form an image.

[0124] In this embodiment, the third discharge means discharges the second active energy ray curable composition (3) onto the ink (2), and the downstream irradiation means irradiates the discharged second active energy ray curable composition (3) with active energy rays. In addition, in the medium transport direction, the third discharge means is disposed downstream of the second discharge means, and the downstream irradiation means is disposed downstream of the third discharge means. As the third ejection means, for example, an inkjet head is used.

[0125] -Second active energy ray-curable composition (3)- The second active energy ray-curable composition (3) contains a (meth)acrylamide compound (A) having a (meth)acryl group, a polyfunctional polymerizable compound or a polymerizable oligomer (B), and a polymerization initiator (C), and optionally contains other components such as a hydrogen donor (D). The second active energy ray-curable composition (3) may be referred to as an active energy ray-curable post-treatment liquid, an active energy ray-curable topcoat liquid, etc. Hereinafter, the second active energy ray-curable composition (3) may be simply referred to as composition (3), or may be referred to as a post-treatment liquid, etc.

[0126] The (meth)acrylamide compound (A) having a (meth)acryl group, the polyfunctional polymerizable compound or polymerizable oligomer (B), the polymerization initiator (C) and the hydrogen donor (D) used in the composition (3) are not particularly limited and may be appropriately selected, and may be the same as those in the composition (1). The composition (3) may have the same formulation as the composition (1) or may have a different formulation.

[0127] The content of each component in composition (3) can be the same as that in composition (1). Regarding the content, for example, "in composition (1)" in the above description may be read as "in composition (3)", etc.

[0128] As mentioned above, the (meth)acrylamide compound (A) refers to a compound that has the function of initiating a polymerization reaction and curing by an initiating species such as radicals generated from a polymerization initiator. In addition, among the polyfunctional polymerizable compounds and the polymerizable oligomers (B), the polyfunctional polymerizable compounds refer to those having two or more acryloyl groups or methacryloyl groups, and the polymerizable oligomer refers to those having a degree of polymerization of about 2 to 20 and having two or more acryloyl groups or methacryloyl groups among the polymers formed by polymerizing monomers. In addition, the (meth)acrylic acid refers to a term that collectively refers to acrylic acid, methacrylic acid, and mixtures thereof, and the same applies to other similar expressions.

[0129] <medium> The medium (also referred to as recording medium, etc.) is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include plain paper, coated paper, glossy paper, special paper, offset printing paper, coated paper for offset printing, film, OHP sheet, general-purpose printing paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, nail, artificial nail, and composite materials thereof. Offset printing paper means paper having characteristics such as high surface strength, little fuzzing or peeling, high dimensional stability, little waviness, wrinkles, stretching, etc., and good texture. Offset printing coated paper means paper having characteristics such as suitability for blisters (moderate moisture content, breathability, etc.) in addition to the above characteristics.

[0130] Good image formation is possible even when a non-permeable substrate is used as the medium. A non-permeable substrate is a substrate having a surface with low water permeability and low absorbency, and includes materials that have many cavities inside but are not open to the outside. More quantitatively, in the Bristow method, 1 / 2 Water absorption up to 10mL / m 2 The term "substrate" refers to a substrate that is: As the impermeable substrate, for example, a plastic film such as a polyvinyl chloride resin film, a polyethylene terephthalate (PET) film, a polypropylene film, a polyethylene film, or a polycarbonate film can be suitably used.

[0131] Among the above, coated paper for offset printing is preferred. Coated paper for offset printing is advantageous in that it is relatively inexpensive compared to glossy paper and can provide a smooth and glossy image. However, it has a problem that it has very poor absorbency for water-based ink, and image quality is greatly reduced, such as a decrease in beading quality. However, the device of the present embodiment makes it possible to obtain an image with excellent beading quality, abrasion resistance, and hardness.

[0132] <Example of equipment> An example of the configuration of the image forming apparatus of this embodiment will be described below. Fig. 1 is a schematic diagram of the main parts for explaining an example in which a first discharge means 50, an irradiation means 51, a second discharge means 52, and a conveying means are used. A medium 3 is conveyed in the direction of the arrow in the figure on a platen 10 of the conveying means. The conveying means may have a conveying roller (not shown) or the like.

[0133] In this embodiment, the second ejection means 52 includes a yellow inkjet head 52Y, a cyan inkjet head 52C, a magenta inkjet head 52M, and a black inkjet head 52K, but is not limited to these. Any of these heads may be appropriately selected, or a white inkjet head may be used.

[0134] In this example, a first discharge means 50, an irradiation means 51, and a second discharge means 52 are arranged in this order from upstream to downstream in the transport direction of the medium 3. In the image forming apparatus of this example, in this order from the upstream side in the transport direction of the medium 3, the first discharge means 50 discharges a composition (1), the irradiation means 51 irradiates active energy rays, and the second discharge means 52 discharges an ink (2). In this way, an image (also referred to as a laminate, etc.) is formed on the medium 3.

[0135] The composition (1) is discharged by a first discharge means, and an inkjet head is used as the first discharge means. The composition (1) may be applied to a medium using a bar coater, a roll coater, a gravure coater, a flexo coater, a brush, or the like, but in the case of a nail, a non-contact inkjet head or a brush is preferred. The film thickness of the composition (1) is not particularly limited and can be changed as appropriate, but for example, a wet film thickness of 10 to 60 μm is preferred.

[0136] Another example of the image forming apparatus of this embodiment is shown in Fig. 2. In the example shown in Fig. 2, a third discharge means 53 and a downstream irradiation means 54 are used in addition to the example shown in Fig. 1. In this example, the first discharge means 50, irradiation means 51, second discharge means 52, third discharge means 53, and downstream irradiation means 54 are arranged in this order from upstream to downstream in the transport direction of the medium 3.

[0137] In the image forming apparatus of this example, after ink (2) is discharged by second discharge means 52, composition (3) is discharged by third discharge means 53, and active energy rays are irradiated by downstream irradiation means 54. This makes it possible to form an image having a film made of composition (3), and improve abrasion resistance.

[0138] Next, the image forming apparatus of this embodiment will be described with reference to FIG. 3 with respect to the portions other than those described above. FIG. 3 is a diagram in which the first ejection means and the irradiation means are omitted. The example shown in FIG. 3 is an example in which a line head 14 is used as the second ejection means, and is an example in which inkjet printing is performed by a so-called line head in which the head is fixed. It is also a schematic diagram showing the internal structure of an example of a line head printing apparatus capable of high-speed one-pass printing. The image forming apparatus of this example is referred to as an image recording apparatus 100.

[0139] The paper feed tray 1 in the image recording device 100 has a configuration in which a pressure plate 2 and a paper feed rotor 4 that feeds recording paper 3, which is a recording medium, are attached to a base 5. The pressure plate 2 is rotatable about a rotation axis a attached to the base 5, and is urged toward the paper feed rotor 4 by a pressure plate spring 6.

[0140] A separation pad made of a material with a large coefficient of friction, such as artificial leather, is provided at the portion of the pressure plate 2 facing the paper feed rotor 4 to prevent double feeding of the media 3 (recording paper). Also, a release cam is provided to release the contact between the pressure plate 2 and the paper feed rotor 4.

[0141] In the above configuration, in the standby state, the release cam presses down the pressure plate 2 to a predetermined position. This releases the contact between the pressure plate 2 and the paper feed rotor 4. In this state, when the driving force from the transport roller 7 is transmitted to the paper feed rotor 4 and the release cam via gears or the like, the release cam separates from the pressure plate 2, causing the pressure plate 2 to rise and bringing the paper feed rotor 4 into contact with the recording paper 3. As the paper feed rotor 4 rotates, the recording paper 3 is picked up and begins to be fed, and is separated one sheet at a time by the separation claw. The paper feed rotor 4 rotates to feed the recording paper 3 to the platen 10 via transport guides 8 and 9.

[0142] The medium 3 passes between the transport guides 8 and 9, is guided to the transport roller 7, and is transported to the platen 10 by the transport roller 7 and pinch roller 11. After that, the medium 3 is released from contact with the paper feed rotor 4 again, and the standby state is entered, and the driving force from the transport roller 7 is cut off.

[0143] A paper feed rotor 12 for manual paper feed feeds a medium 3 placed on a manual feed tray 13 in accordance with a recording command signal from a computer, and conveys the medium 3 to a conveying roller 7. The medium 3 conveyed to a platen 10 passes under a line head 14. Here, the speed of conveying the recording paper, the timing of ejecting the composition or ink, and the like are controlled by signals from an electrical circuit, and the image recording device forms a desired image.

[0144] In this example, a composition (1) is ejected onto a medium 3 by a first ejection means, not shown here, active energy rays are irradiated by an irradiation means, not shown here, and an ink (2) is ejected by a line head 14.

[0145] Next, another example of the irradiation means will be described with reference to Fig. 4. Fig. 4 is a schematic diagram showing the internal structure of an example of a UV irradiation device that is externally added to, for example, the line head 14 in Fig. 3. In this example, two UV irradiation units are provided to perform a faster fixing process.

[0146] In the example shown in Fig. 4, A indicates a UV irradiation unit, B indicates a UV lamp, and as the UV lamp, for example, a medium pressure mercury lamp (HOK4 / 120 manufactured by Philips) with an output of 400 W is suitably used. C indicates an electrostatic conveyor belt. A medium is conveyed to the electrostatic conveyor belt C, and UV is irradiated onto the medium.

[0147] The UV irradiation device is disposed upstream of the second ejection means in the medium transport direction, for example, upstream of the line head 14 shown in Fig. 3. When irradiating the medium with UV after ejection of the ink (2), the UV irradiation device can be installed at the positions of the paper ejection units 17, 18, and 19 in Fig. 3, for example.

[0148] Second Embodiment Next, an image forming apparatus and an image forming method according to another embodiment of the present invention will be described.

[0149] The image forming apparatus of the present embodiment has a carriage member that scans over a medium, and the first discharge means, the irradiation means and the second discharge means are provided on the carriage member.

[0150] A schematic diagram of an example of the image forming apparatus of this embodiment is shown in Fig. 5. In this example, the medium is a nail 21 of a finger 22, and a modeling device 39 of this example forms an image on the nail 21. The image forming apparatus of this example includes a carriage member 24, which is movable, for example, in the direction AB in the figure, and performs reciprocating scanning.

[0151] The carriage member 24 includes a first discharge means 30, irradiation means 31a, 31b, and a second discharge means 32. The first discharge means 30 uses an inkjet head, and the second discharge means 32 uses a head unit in which inkjet heads of different colors are arranged. In addition, two irradiation means 31a, 31b are used, so that the composition (1) and the ink (2) can be discharged on the forward and return paths.

[0152] The image forming apparatus of this example has a jig 37 for fixing the finger 22. The jig 37 preferably fixes the finger 22 so that the finger 22 does not move significantly, and by fixing the finger 22 by the jig 37 so as not to move, it is possible to suppress deviation of the ejection position of the composition. The finger 22 may be said to be fixed to the jig 37, or may be said to be fixed to the stage 38. The fixing position of the jig 37 may be manually adjusted by a user or the like to match the finger 22, or the fixing position may be automatically adjusted by the image forming apparatus.

[0153] The distance between the claw 21 (medium) and the carriage member 24 may be appropriately changed, for example, the stage 38 may be configured to be able to rise or fall. When the thickness of the image is increased by repeatedly ejecting the composition (1), the ink (2), or the like, the distance between the claw 21 and the carriage member 24 may be appropriately changed.

[0154] The image forming apparatus of the present invention can not only form two-dimensional characters, images, and decorative coatings on various substrates, but also form images on nails and nail-shaped plastic substrates, and can form nail-shaped images (cured products, structures) such as artificial nails. The composition (1) used in the present invention is excellent in removability and nail adhesion, and is particularly suitable for use as a base coat for artificial nail compositions. In addition, as described below, the present embodiment may also use composition (3), and when composition (3) is used, the surface hardness can be improved, and it is suitable for use as a top coat for artificial nail compositions.

[0155] According to the image forming apparatus of the present embodiment, it is possible to form decorations, artificial nails, etc. on a medium. Artificial nails include those that form synthetic resin fake nails on nails (natural nails).

[0156] In this embodiment, the composition (1) and the composition (3) may be used as a nail decoration material. The nail decoration material includes manicure, pedicure, sculpture, gel nail, etc., which are used for decorating or strengthening nails.

[0157] The composition (1) and composition (3) used in this embodiment may be referred to as an artificial nail composition, etc., and the artificial nail composition used in this embodiment is a composition that is applied onto a human or animal nail or onto another artificial nail, and then hardened by exposure to light to form an artificial nail. In addition, the artificial nail formed by this embodiment can also be removed by a removal method using an organic solvent, etc.

[0158] In the present embodiment, the artificial nail refers to a layer formed on a human or animal nail or on another artificial nail for the purpose of beautifying and / or protecting the nail. In addition, for example, the other artificial nail may be a resin base material (false nail) of any shape for the purpose of beautifying and / or protecting the nail. In addition, "human and animal nails, and other artificial nails" may also be simply referred to as "nails".

[0159] The shape of the artificial nail is not particularly limited, and it may be formed into a desired shape. For example, it may be formed so as to cover the surface of the nail, may be formed only on a part of the nail, or may be formed into a shape larger than the nail by using a nail form or the like to extend the nail.

[0160] In this embodiment, the thickness of the artificial nail formed can be appropriately controlled. The thickness of the entire artificial nail is not particularly limited as long as it is within the range that an artificial nail can generally have, but from the viewpoints of durability and removability, it is preferably in the range of 10 μm or more and 2,000 μm or less.

[0161] The artificial nail generally has a layer structure including, in order from the closest to the nail, one or more of the following: a primer layer (a layer between the nail and the base layer to improve adhesion when the base layer alone does not have sufficient adhesion to the nail), a base layer (a layer between the nail and the color layer to improve adhesion and prevent color transfer to the nail), a color layer (a layer containing a coloring material), and a top layer (an outermost layer to improve durability, gloss, and aesthetics). In this embodiment, for example, the primer layer and the base layer are formed by the composition (1), and the color layer is formed by the ink (2). In the example described below, the top layer can be formed by the composition (3).

[0162] Next, another example of the image forming apparatus of this embodiment is shown in FIG. In the image forming apparatus of this example, the carriage member 24 is provided with a third discharge means 33 that discharges the composition (3). The arrangement of the first discharge means 30, the irradiation means 31a, 31b, the second discharge means 32 and the third discharge means 33 in the carriage member 24 is not limited to that shown in the figure and can be changed as appropriate.

[0163] In this example, after the second discharge means 32 discharges the ink (2), the third discharge means 33 discharges the composition (3), and then the irradiation means 31a and 31b irradiate the nail with active energy rays. This allows an image having a film of the composition (3) to be formed on the nail 21.

[0164] When the composition (3) has the same formulation as the composition (1), the first discharge means 30 may also serve as the third discharge means 33.

[0165] Next, another example of the image forming apparatus of this embodiment is shown in FIG. The image forming device of this example has an imaging means 35 capable of detecting the smoothness of the surface of the nail 21 (medium), and a smoothing means 40 that smooths the surface of the medium based on the detection result of the imaging means 35. By smoothing the surface of the medium using the smoothing means 40, it is possible to improve the adhesion between the medium and a film made of the composition (1), and to prevent the image from coming off the nail 21. In addition, by using the imaging means 35, it is possible to prevent the surface of the nail 21 from being unnecessarily smoothed, and for example, it is possible to prevent the nail 21 from being filed down too much.

[0166] In this example, both the imaging means 35 and the smoothing means 40 are used, but the present embodiment is not limited to this. For example, it is also possible to use only the smoothing means 40 and not the imaging means 35. The imaging means 35 is preferably used as a means for detecting the smoothness of the surface of the nail 21, but other means may be used. Furthermore, detecting the smoothness of the surface of the medium may also be expressed as detecting the unevenness of the surface of the medium.

[0167] In this example, the first discharge means 30 preferably discharges the first active energy ray curable composition (1) onto the medium when the surface of the medium has a predetermined smoothness. In addition, in this example, the first discharge means 30 preferably discharges the first active energy ray curable composition (1) onto the medium when the surface of the medium does not have a predetermined smoothness, after the surface of the medium has been smoothed by the smoothing means 40. In this way, the surface of the medium can be smoothed by the smoothing means 40 only when necessary, and for example, it is possible to prevent the nail 21 from being scraped too much.

[0168] The decision as to whether or not the smoothing means 40 should perform the operation of smoothing the surface of the medium (hereinafter also referred to as the smoothing operation) can be changed appropriately depending on the situation and is not limited. For example, it is preferable to perform the smoothing operation when the difference between the most concave and most convex parts of the surface of the nail 21 is 20 μm or more as the above-mentioned predetermined smoothness.

[0169] The smoothing means 40 is not particularly limited and can be changed as appropriate. For example, it is preferable to use a file. By using a file, the surface of the medium can be efficiently smoothed. In addition, the coarseness of the file can be changed as appropriate depending on the situation, which can prevent the surface from being under-scraped or being over-scraped.

[0170] When using a file, the way in which the file is moved can be changed as appropriate, for example, it can be moved back and forth or rotated. Of these, it is preferable to rotate the file, for example, by attaching the file to a rotatable support rod and rotating it. The shape of the file is not particularly limited and can be changed as appropriate, for example, a sheet shape, a rectangular parallelepiped, a cube, a sphere, etc.

[0171] The position of the smoothing means 40 is not limited to that shown in the drawing and can be changed as appropriate. In addition, the smoothing means 40 may be moved to a position corresponding to the nails 21, or, for example, the stage 38 may be moved to a position corresponding to the smoothing means 40.

[0172] As the imaging means 35, for example, a camera is used. The arrangement position of the imaging means 35 is not limited to that shown in the figure and can be changed as appropriate. It may be fixed inside the device, or may be arranged on the carriage member 24, for example. When arranged on the carriage member 24, it may be arranged at a position adjacent to the irradiation means, for example. In addition, the number of imaging means 35 can be changed as appropriate, and may be one or more.

[0173] In addition, when the imaging means 35 is used, it is preferable that the first discharge means 30 and the irradiation means 31a, 31b repeat the discharge of the first active energy ray-curable composition (1) and the irradiation of active energy rays until the surface of the medium has a predetermined smoothness. In this case, for example, unevenness of a nail can be filled in, and the ink (2) can be discharged onto a smooth base.

[0174] Next, another example of the image forming apparatus of this embodiment is shown in FIG. The image forming apparatus of this example has an image acquiring means 41 for acquiring an image of the first active energy ray curable composition (1) after it has been irradiated with active energy rays by the irradiation means 31a, 31b, and a temperature acquiring means 42 for acquiring the temperature in a non-contact manner. Furthermore, the second ejection means 32 in this example controls whether or not to eject the ink (2) based on the information acquired by the image acquiring means 41 and / or the temperature acquiring means 42.

[0175] According to this example, by using the image acquisition means 41 and the temperature acquisition means 42, the degree of hardening of the composition (1) can be acquired, and based on the acquired information, it is possible to control whether or not the second ejection means 32 ejects the ink (2). This makes it possible to control, for example, to not eject the ink (2) when the composition (1) is not sufficiently hardened, thereby preventing the ink (2) from bleeding and making it easier to obtain a clear image.

[0176] The image acquisition means 41 in this example is for acquiring an image of the composition (1) after irradiation with active energy rays, and for example, a camera is used. The imaging means 35 in the above example may be used as the image acquisition means 41 in this example. The position of the image acquisition means 41 is not limited to that shown in the figure, and may be changed as appropriate. It may be fixed within the device, or may be disposed on the carriage member 24, for example.

[0177] The temperature acquisition means 42 acquires the temperature of the composition (1) after irradiation with active energy rays. The location of the temperature acquisition means 42 is not limited to that shown in the drawing and can be changed as appropriate. It may be fixed inside the device, or may be disposed on the carriage member 24, for example.

[0178] The judgment of whether or not to eject the ink (2) can be appropriately changed and is not particularly limited. Although it cannot be generalized because it varies depending on the composition (1) and the active energy rays, for example, when the smoothness in the image acquired by the image acquisition means 41 is a predetermined value or less, for example, the difference between the most concave part and the most convex part is 20 μm or less, and when the temperature of the film surface acquired by the temperature acquisition means 42 is within a predetermined range, for example, 20°C or more and 40°C or less, the ink (2) is ejected. In addition, for example, when the smoothness in the image acquired by the image acquisition means 41 is greater than a predetermined value, for example, when the difference between the most concave part and the most convex part is greater than 20 μm, the ink (2) is not ejected, and when the temperature of the film surface acquired by the temperature acquisition means 42 is less than 20°C, the ink (2) is not ejected. EXAMPLES

[0179] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. In addition, unless otherwise specified, "parts" refers to parts by mass and "%" refers to % by mass.

[0180] (Examples 1 to 26, Comparative Examples 1 to 11) <Components> The abbreviations, compound names, manufacturer names, and product names of the raw materials used in the preparation of each composition are shown in Tables 1 and 2. A1-1 to A1-3, which are acrylamide compounds (A1), were synthesized by the methods shown in Synthesis Examples 1 to 3. The synthesized compounds were identified by nuclear magnetic resonance spectroscopy (apparatus used: "JNM-ECX500" manufactured by JEOL Ltd.), and the purity was measured by gas chromatography (apparatus used: "GCMS-QP2010 Plus" manufactured by Shimadzu Corporation). These chemical analyses were carried out according to established methods.

[0181] <Synthesis Example 1> <<Synthesis of N-acryloyl-N-methylglycine methyl ester (A1-1)>> 0.30 mol of N-methylglycine methyl ester hydrochloride (reagent manufactured by Sigma-Aldrich Japan LLC), 0.45 mol of potassium carbonate (reagent manufactured by Kanto Chemical Co., Inc.), and 400 mL of water were stirred and mixed at 0 to 10 °C, and while maintaining this temperature, 0.33 mol of acryloyl chloride (reagent manufactured by Wako Pure Chemical Industries, Ltd.) was slowly added dropwise. After completion of the dropwise addition, extraction was carried out 3 times with 400 mL of ethyl acetate (reagent manufactured by Kanto Chemical Co., Inc.), and the combined ethyl acetate layers were washed once with 400 mL of water. Ethyl acetate was distilled off under reduced pressure at 40 °C to obtain 0.20 mol of the target N-acryloyl-N-methylglycine methyl ester (A1-1) as a nearly colorless transparent liquid. The purity was 98.3% by mass. The molecular weight of N-acryloyl-N-methylglycine methyl ester (A1-1) is 157.2, and it is a known compound (CAS registration number 72065-23-7).

[0182] <Synthesis Example 2> <<Synthesis of N-acryloyl-N-methylalanine methyl ester (A1-2)>> In Synthesis Example 1, 0.22 mol of the target N-acryloyl-N-methylalanine methyl ester (A1-2) was obtained as a nearly colorless transparent liquid in the same manner as in Synthesis Example 1, except that N-methylglycine methyl ester hydrochloride was changed to N-methylalanine methyl ester hydrochloride (reagent manufactured by Tokyo Chemical Industry Co., Ltd.). The purity was 98.5% by mass. Incidentally, the molecular weight of N-acryloyl-N-methylalanine methyl ester (A1-2) was 171.2.

[0183] <Synthesis Example 3> <<Synthesis of Ethyl N-acryloylpiperidine-4-carboxylate (A1-3)>> In Synthesis Example 1, 0.27 mol of the target ethyl N-acryloylpiperidine-4-carboxylate (A1-3) was obtained as a nearly colorless and transparent liquid in the same manner as in Synthesis Example 1, except that methyl N-methylglycinate hydrochloride was changed to ethyl piperidine-4-carboxylate (manufactured by Tokyo Chemical Industry Co., Ltd., reagent). The purity was 99.2% by mass. Incidentally, the molecular weight of ethyl N-acryloylpiperidine-4-carboxylate (A1-3) is 211.3, and it is a known compound (CAS registration number 845907-79-1).

[0184] <Preparation of the First Active Energy Ray-Curable Composition (1)> According to the formulations shown in Tables 3 to 7, the (meth)acrylamide compound (A), acrylamide compound (A1), other monomers (E), polymerization initiator (C), hydrogen donor (D), etc. were appropriately selected and mixed, and dispersed and stirred with a dissolver (DISPERMAT-FE). This was filtered through a 3-μm filter to obtain the first active energy ray-curable composition (1) (active energy ray-curable base coat liquid). Incidentally, each table also shows the blending ratio (mass%) of each component.

[0185] <Preparation of Ink (2)> According to the formulations shown in Tables 8 to 10, Ink (2) (aqueous ink for inkjet recording) was prepared as follows. The materials (i) to (vii) used are shown below. (i) Pigment (unmodified pigment (surfactant-dispersed pigment)) (ii) Surfactant (iii) Water-soluble organic solvent (iv) Ion-exchanged water (v) pH adjuster (vi) Preservative (vii) Rust inhibitors

[0186] Of the above materials, (iv) ion-exchanged water, (iii) water-soluble organic solvent, (vi) preservative, and (vii) rust inhibitor were added and dispersed and stirred with a dissolver (DISPERMAT-FE) to prepare a dispersion. (i) Pigment and (ii) surfactant were added to this dispersion, and after dispersing and stirring with a bead mill (Ashizawa Labostar), (v) pH adjuster was further added to prepare a pigment dispersion. Ink (2) was obtained by filtering this pigment dispersion with a 3 μm filter. Each table also shows the blending ratio (mass %) of each component.

[0187] The abbreviations shown in each table are as follows. Pigments C=Cyan M=Magenta Y=Yellow B=Black PB15:4=CI Pigment Blue 15:4 (phthalocyanine blue) PR122=CIPigment Red 122(dimethyl quinacridone) PY74=CIPigment Yellow 74(monoazo) Acidic CB = Acidic carbon black Surfactants TEGO Wet270 = Polyether modified siloxane compound (manufactured by Evonik) Water-soluble organic solvents MBD = 3-methyl-1,3-butanediol EHD = 2-ethyl-1,3-hexanediol pH adjuster TEA = Triethanolamine (organic amine) Preservatives BIT = 1,2-Benzisothiazolin-3-one Rust inhibitor BTA = Benzotriazole

[0188] <Preparation of second active energy ray-curable composition (3)> According to the formulations shown in Tables 4 to 7, the (meth)acrylamide compound (A), the acrylamide compound (A1), the polyfunctional polymerizable compound or polymerizable oligomer (B), the polymerization initiator (C), the hydrogen donor (D), and the like were appropriately selected and mixed, and dispersed and stirred with a dissolver (DISPERMAT-FE). This was filtered through a 3 μm filter to obtain a second active energy ray-curable composition (3) (active energy ray-curable topcoat liquid). Each table also shows the blending ratio (mass %) of each component.

[0189] In the table below, "liquid type (1)" indicates the first active energy ray-curable composition (1), "liquid type (2)" indicates the ink (2), and "liquid type (3)" indicates the second active energy ray-curable composition (3).

[0190] [Table 1]

[0191] [Table 2]

[0192] [Table 3]

[0193] [Table 4]

[0194] [Table 5]

[0195] [Table 6]

[0196] [Table 7]

[0197] [Table 8]

[0198] [Table 9]

[0199] [Table 10]

[0200] (evaluation) <Device configuration and image formation> In the following evaluation, an image forming apparatus having the configuration shown in FIG. 1 or FIG. 2 was used. The first active energy ray curable composition (1) and the second active energy ray curable composition (3) were incorporated into an image forming apparatus equipped with an inkjet head (manufactured by Ricoh Company, Ltd., "MH5440") as a discharge means. The image forming apparatus used had a UV-LED (manufactured by Integration Technology Japan, Inc., "LED ZERO", wavelength 395 nm, illuminance at the irradiation surface 1.0 W / cm) as an irradiation means. 2 The image forming apparatus used also includes a controller for controlling the ejection, a composition container, and a supply path from the composition container to the inkjet head.

[0201] The temperature of the inkjet head was appropriately adjusted (30 to 60°C) so that the viscosity of composition (1) was 10 mPa·s to 12 mPa·s, and composition (1) was ejected to a film thickness of 10 μm onto a commercially available PET film (manufactured by Toyobo Co., Ltd., "Cosmoshine A4100", thickness 188 μm), which is a general-purpose film material. Next, ultraviolet light was irradiated using a UV-LED provided in the irradiation means. Next, ink (2) was ejected to form an image. In some examples, the composition (3) was then ejected from the inkjet head and irradiated with ultraviolet light from a UV-LED to form an image. The temperature of the composition (3) was also adjusted (30 to 60°C) so that the viscosity was 10 mPa s to 12 mPa s. Only in Comparative Example 11, after the ink (2) was ejected, the first active energy ray-curable composition (1) was ejected and ultraviolet light was irradiated using the UV-LED of the irradiation means.

[0202] <Curing property evaluation (measurement of accumulated light irradiation amount)> The image obtained above was judged to be cured when it reached a state where it was no longer sticky when touched with a finger, and the cumulative amount of irradiation light required for curing was calculated. 2 The following cases were deemed feasible:

[0203] <Hardness> The pencil hardness of the obtained image was measured in accordance with JIS K5600-5-4 scratch hardness (pencil method) using the following device and equipment. A hardness of HB or higher was deemed to be usable.

[0204] -Apparatus and equipment- Equipment: COTEC scratch pencil hardness TQC WW tester (750g load only) Pencils: Wooden drafting pencil set (manufactured by Mitsubishi Pencil Co., Ltd.) with the following hardness: 6B, 5B, 4B, 3B, 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H Pencil sharpener: A special sharpener that scrapes off only the wood part of the pencil, leaving the cylindrical core intact. In addition, when ink with low curing property is cured with the above-mentioned light amount, it does not harden sufficiently and the hardness is also low.

[0205] <Viscosity measurement> The viscosities of Composition (1) and Composition (3) were measured using a cone-plate type rotational viscometer VISCOMETER TVE-22L manufactured by Toki Sangyo Co., Ltd., with a cone rotor (1°34'×R24), at a rotation speed of 50 rpm and with the temperature of the constant temperature circulating water adjusted to 25° C. A VISCOMATE VM-150III was used to adjust the temperature of the circulating water.

[0206] <Evaluation of beading quality (uneven density)> After the composition (1) was discharged onto the PET film and irradiated with UV light, the ink (2) was discharged onto the PET film to produce solid images in cyan, magenta, yellow, black, and white. The solid images were observed for uneven density (beading) and evaluated according to the following criteria.

[0207] [Evaluation Criteria] ◎: No image unevenness at all ○: There is slight unevenness in the image ×: Image is uneven

[0208] <Abrasion resistance (fixability)> The fixability of the obtained image was evaluated according to "JISL0849-Test method for color fastness to friction". The transfer density to the cotton fabric was evaluated on a 5-point scale according to the following evaluation criteria. The higher the number, the better the result.

[0209] [Evaluation Criteria] 5: Very little metastasis 4: Slightly less metastasis 3: Moderate metastasis 2: Metastasis is somewhat frequent 1: Very high metastasis

[0210] [Table 11]

[0211] [Table 12]

[0212] [Table 13]

[0213] In Tables 11 to 13, the cumulative amount of irradiation light and the viscosity required for curing were measured for Composition (1) and Composition (3), respectively, so each table has a column for the type of liquid. In Table 13, "*1" indicates that the cumulative irradiation dose is 10 J / cm 2 In addition, the pencil hardness "-" in Table 13 means that it could not be measured. [Explanation of symbols]

[0214] 1 Paper feed tray 2 Pressure Plate 3 Medium 4 Paper feed rotor 5. Bass 6. Plate spring 7 Transport roller 8, 9 Transport guide 10 Platen 11 Pinch roller 12 Manual feed paper feed rotor 13 Manual feed tray 14 Line Head 17, 18, 19 Paper ejection section 21 Nails 22 fingers 24 Carriage member 30 First discharge means 31 Irradiation means 32 Second discharge means 33 Third Discharge Means 35 Imaging Method 37 Jig 38 Stages 40 Smoothing means 41 Image Acquisition Method 42 Temperature acquisition means 50 First discharge means 51 Irradiation means 52 Second Discharge Means 53 Third Discharge Means 54 Downstream irradiation means 100 Image recording device A UV irradiation unit B Medium pressure mercury lamp C Electrostatic conveyor belt [Prior art documents] [Patent documents]

[0215] [Patent Document 1] JP 2004-330568 A [Patent Document 2] JP 2010-105187 A [Patent Document 3] JP 2010-115854 A [Patent Document 4] JP 2007-054983 A [Patent Document 5] JP 2007-276387 A [Patent Document 6] JP 2002-332433 A

Claims

1. a first discharge means for discharging a first active energy ray-curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C) onto a medium; an irradiation means for irradiating the first active energy ray-curable composition (1) discharged onto the medium with active energy rays; and a second ejection means for ejecting an ink (2) containing a coloring material, a water-soluble organic solvent, and water onto the first active energy ray-curable composition (1) irradiated with the active energy ray, The (meth)acrylamide compound (A) having a (meth)acryl group comprises an acrylamide compound (A1) represented by the following general formula (1) or (2): 【Chemistry 1】 (In the above general formula (1), R 1 represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, R 2 represents a linear or branched alkylene group having 1 to 4 carbon atoms, and R 3 represents a linear or branched alkyl group having 1 to 4 carbon atoms, with the proviso that the total number of carbon atoms in R 1 , R 2 and R 3 is 2 to 6.) 【Chemistry 2】 (In the above general formula (2), ring X represents a ring structure containing a nitrogen atom and having 2 to 5 carbon atoms, R 4 represents a single bond or a linear or branched alkylene group having 1 to 3 carbon atoms, and R 5 represents a linear or branched alkyl group having 1 to 3 carbon atoms, with the proviso that the total number of carbon atoms in ring X, R 4 and R 5 is 3 to 6.)

2. a third ejection means for ejecting a second active energy ray-curable composition (3) onto the ink (2), the second active energy ray-curable composition (3) including a (meth)acrylamide compound (A) having a (meth)acryl group, a polyfunctional polymerizable compound or a polymerizable oligomer (B), and a polymerization initiator (C); and 2. The image forming apparatus according to claim 1, further comprising: an irradiation means for irradiating the discharged second active energy ray-curable composition (3) with active energy rays.

3. A conveying means for conveying the medium is provided, 2. The image forming apparatus according to claim 1, wherein the first discharge means, the irradiation means, and the second discharge means are disposed in this order from upstream to downstream in a transport direction of the medium.

4. A conveying means for conveying the medium is provided, When the irradiation means for irradiating the second active energy ray-curable composition (3) with active energy rays is a downstream irradiation means, 3. The image forming apparatus according to claim 2, wherein the first ejection means, the irradiation means, the second ejection means, the third ejection means, and the downstream irradiation means are arranged in this order from upstream to downstream in a transport direction of the medium.

5. a carriage member for scanning over the medium; 2. The image forming apparatus according to claim 1, wherein said first ejection means, said irradiation means and said second ejection means are provided on said carriage member.

6. 6. The image forming apparatus according to claim 5, wherein the carriage member is provided with a third ejection means for ejecting a second active energy ray-curable composition (3) containing a (meth)acrylamide compound (A) having a (meth)acryl group, a polyfunctional polymerizable compound or a polymerizable oligomer (B), and a polymerization initiator (C).

7. 7. An image forming apparatus according to claim 5, wherein the medium is a fingernail, and further comprising a jig for fixing the finger.

8. 8. The image forming apparatus according to claim 5, further comprising a smoothing means for smoothing the surface of the medium.

9. 9. The image forming apparatus according to claim 8, wherein the first ejection means ejects the first active energy ray curable composition (1) onto a medium when the surface of the medium has a predetermined smoothness, and when the surface of the medium does not have the predetermined smoothness, the first active energy ray curable composition (1) is ejected after the surface of the medium has been smoothed by the smoothing means.

10. 10. The image forming apparatus according to claim 8, wherein the first ejection means and the irradiation means repeat ejection of the first active energy ray-curable composition (1) and irradiation of the active energy ray until the surface of the medium has a predetermined smoothness.

11. 11. The image forming apparatus according to claim 5, further comprising an imaging means capable of detecting the smoothness of the surface of the medium.

12. an image acquiring means for acquiring an image of the first active energy ray-curable composition (1) after the first active energy ray-cured composition (1) has been irradiated with active energy rays by the irradiation means, and a temperature acquiring means for acquiring a temperature in a non-contact manner; An image forming apparatus according to any one of claims 5 to 11, characterized in that the second ejection means controls whether or not to eject the ink (2) based on information acquired by the image acquisition means and / or the temperature acquisition means.

13. 13. The image forming apparatus according to claim 1, wherein the first active energy ray-curable composition (1) contains a polyfunctional polymerizable compound or a polymerizable oligomer (B).

14. 7. The image forming apparatus according to claim 2, wherein the first active energy ray curable composition (1) and / or the second active energy ray curable composition (3) contains a hydrogen donor (D).

15. 15. The image forming apparatus according to claim 1, wherein the active energy rays are ultraviolet rays having a peak wavelength of 365 nm or more and 405 nm or less.

16. The amount of irradiation of the active energy rays is 10 mJ / cm ２ More than 500mJ / cm ２ 16. The image forming apparatus according to claim 1, wherein:

17. a first discharge step of discharging a first active energy ray-curable composition (1) containing a (meth)acrylamide compound (A) having a (meth)acryl group and a polymerization initiator (C) onto a medium; an irradiation step of irradiating the first active energy ray-curable composition (1) discharged onto the medium with active energy rays; a second ejection step of ejecting an ink (2) containing a coloring material, a water-soluble organic solvent, and water onto the first active energy ray-curable composition (1) irradiated with the active energy ray, The image forming method, wherein the (meth)acrylamide compound (A) having a (meth)acryl group contains an acrylamide compound (A1) represented by the following general formula (1) or (2): 【Chemistry 3】 (In the above general formula (1), R 1 represents a hydrogen atom or a linear or branched alkyl group having 1 to 4 carbon atoms, R 2 represents a linear or branched alkylene group having 1 to 4 carbon atoms, and R 3 represents a linear or branched alkyl group having 1 to 4 carbon atoms, with the proviso that the total number of carbon atoms in R 1 , R 2 and R 3 is 2 to 6.) 【Chemistry 4】 (In the above general formula (2), ring X represents a ring structure containing a nitrogen atom and having 2 to 5 carbon atoms, R 4 represents a single bond or a linear or branched alkylene group having 1 to 3 carbon atoms, and R 5 represents a linear or branched alkyl group having 1 to 3 carbon atoms, with the proviso that the total number of carbon atoms in ring X, R 4 and R 5 is 3 to 6.)

Images