Aqueous dispersion and film-forming method

Abstract

Provided are an aqueous dispersion and a film formation method. The aqueous dispersion contains water and particles that include a resin and a photoradical generator and have a polymerizable group. The polymerizable group includes an ethylenic double bond. The ratio of the number of moles of the photoradical generator relative to the number of moles of the ethylenic double bond in the particles is at least 4 mol%. The ratio of the number of moles of photoradical generator present as a solid relative the total number of moles of the photoradical generator is no more than 5 mol%.

Description

[Technical Field]

[0001] The present disclosure relates to aqueous dispersions and methods for forming films. [Background technology]

[0002] BACKGROUND ART Conventionally, an aqueous dispersion of microcapsules, in which microcapsules each including a core and a shell are dispersed in an aqueous medium (a medium containing water), has been known. For example, Japanese Patent No. 6584677 describes an aqueous dispersion containing water and particles that include a chain polymer containing the structural unit (1), the structural unit (2), and a hydrophilic group and that include a polymerizable group. Japanese Patent Application Laid-Open No. 2013-202928 describes an emulsion of a solvent-philic linear urethane (meth)acrylate containing a photopolymerization initiator and a polymerizable compound. WO 2021 / 059933 describes an aqueous dispersion containing particles including a polymer P containing a bond U, which is at least one selected from the group consisting of a urethane bond and a urea bond, and a hydrophilic group, a polymerizable monomer, and a structure A, which is at least one selected from the group consisting of a polysiloxane bond and a fluorohydrocarbon group, and water. Summary of the Invention [Problem to be solved by the invention]

[0003] In a film formed by applying an aqueous dispersion onto a substrate and curing the applied dispersion, it is sometimes required to prevent components contained in the aqueous dispersion from eluting (i.e., migrating) from the film.

[0004] According to one aspect of the present disclosure, there are provided an aqueous dispersion and a film-forming method in which migration is suppressed. [Means for solving the problem]

[0005] The present disclosure includes the following aspects. <1> An aqueous dispersion comprising water and particles containing a resin and a photoradical generator and having a polymerizable group, wherein the polymerizable group contains an ethylenic double bond, and the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles is 4 mol% or more, and the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator is 5 mol% or less. <2> the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bond is 5 mol % to 40 mol %; <1> The aqueous dispersion according to claim 1. <3> The HSP distance between the resin and the photoradical generator is 5.5 MPa. 1 / 2 Below is the <1> or <2> The aqueous dispersion according to claim 1. <4> The particles further have an amino group A having a hydrogen atom at the α-position carbon atom, <1> ~ <3> 1. The aqueous dispersion according to any one of the preceding items. <5> the ratio of the number of moles of the amino group A having a hydrogen atom on the carbon atom at the α-position to the total number of moles of the photoradical generator is 5 mol % to 100 mol %; <4> The aqueous dispersion according to claim 1. <6> The particles further comprise a compound having an amino group A having a hydrogen atom at the α-position carbon atom, <4> or <5> The aqueous dispersion according to claim 1. <7> In the particles, the ratio of the number of moles of the compound having an amino group A present as a solid to the total number of moles of the compound having an amino group A is 5 mol % or less. <6> The aqueous dispersion according to claim 1. <8> The HSP distance between the photoradical generator and the compound having an amino group A with a hydrogen atom on the α-position carbon atom is 6 MPa. 1 / 2 Below is the <6> or <7> The aqueous dispersion according to claim 1. <9> The resin has a glass transition temperature of 90°C or less. <1> ~ <8> 1. The aqueous dispersion according to any one of the preceding items. <10> The photoradical generator contains a hydrogen abstraction initiator having a number average molecular weight of 1000 or more. <1> ~ <9> 1. The aqueous dispersion according to any one of the preceding items. <11> the particle comprises a polymerizable monomer, and the polymerizable group comprises a polymerizable group of the polymerizable monomer; <1> ~ <10> 1. The aqueous dispersion according to any one of the preceding items. <12> It is an inkjet ink, <11> The aqueous dispersion according to claim 1. <13> On the substrate, <1> ~ <12> and curing the aqueous dispersion applied onto a substrate. [Effects of the Invention]

[0006] According to one aspect of the present disclosure, there are provided an aqueous dispersion and a film-forming method in which migration is suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0007] In the present disclosure, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the present disclosure, when a plurality of substances corresponding to each component are present in the composition, the amount of each component in the composition means the total amount of the plurality of substances present in the composition, unless otherwise specified. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in a certain numerical range may be replaced by the upper or lower limit value of another numerical range described in stages, or may be replaced by a value shown in an example. In the present disclosure, the term "process" includes not only an independent process but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved. In the present disclosure, "*" in a chemical formula indicates a bond position.

[0008] In the present disclosure, the concept of "image" includes not only pattern images (for example, characters, symbols, or graphics) but also solid images. In the present disclosure, the term "light" is a concept that encompasses active energy rays such as gamma rays, beta rays, electron beams, ultraviolet rays, and visible light. In this disclosure, ultraviolet light may be referred to as "UV (Ultra Violet) light." In this disclosure, light generated from an LED (Light Emitting Diode) light source may be referred to as "LED light." In the present disclosure, "(meth)acrylic acid" is a concept that encompasses both acrylic acid and methacrylic acid, "(meth)acrylate" is a concept that encompasses both acrylate and methacrylate, and "(meth)acryloyl group" is a concept that encompasses both acryloyl group and methacryloyl group.

[0009] [Aqueous dispersion] The aqueous dispersion of the present disclosure contains water and particles (hereinafter also referred to as "specific particles") that contain a resin and a photoradical generator and have a polymerizable group, wherein the polymerizable group contains an ethylenic double bond, and the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles is 4 mol% or more, and the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator is 5 mol% or less.

[0010] The aqueous dispersion of the present disclosure suppresses migration. The reason why the above effect is achieved is presumed to be as follows. The formation of a film using the aqueous dispersion can be carried out, for example, by applying an aqueous dispersion containing specific particles onto a substrate and irradiating the specific particles applied to the substrate with light. This operation causes a polymerization reaction to proceed due to the polymerizable groups of the specific particles applied to the substrate, and a film (i.e., a cured film) is formed. In the aqueous dispersion of the present disclosure, the ratio of the number of moles of photoradical generator to the number of moles of ethylenic double bonds is 4 mol% or more, which promotes the polymerization reaction and improves the crosslink density. As a result, it is believed that migration is suppressed. Furthermore, in the aqueous dispersion of the present disclosure, the ratio of the number of moles of photoradical generator present as a solid to the total number of moles of photoradical generator is 5 mol% or less, which improves the mobility of radicals generated from the photoradical generator and polymerizable groups, thereby improving the crosslink density. As a result, it is believed that migration is suppressed.

[0011] On the other hand, Japanese Patent No. 6584677 and International Publication No. 2021 / 059933 disclose an embodiment in which the ratio of the number of moles of photoradical generator to the number of moles of ethylenic double bonds is less than 4 mol%. Furthermore, Japanese Patent Laid-Open Publication No. 2013-202928 discloses an embodiment in which the ratio of the number of moles of photoradical generator present as a solid to the total number of moles of photoradical generator is greater than 5 mol%. Japanese Patent No. 6584677, Japanese Patent Laid-Open Publication No. 2013-202928, and International Publication No. 2021 / 059933 do not pay attention to the content of photoradical generator relative to the C=C valence of the particle, or the proportion of photoradical generator present as a solid within the particle.

[0012] Each component that can be contained in the aqueous dispersion will be described below.

[0013] [Specific particles] The aqueous dispersion of the present disclosure contains specific particles. As described above, the specific particles contain a resin and a photoradical generator and have a polymerizable group.

[0014] (polymerizable group) Examples of the specific particles having a polymerizable group include the following. Aspect 1: Aspect in which the resin contained in the specific particles has a polymerizable group Aspect 2: Aspect in which the specific particles further contain a polymerizable monomer in addition to the resin and the photoradical generator Aspect 3: Aspect in which the resin contained in the specific particles has a polymerizable group, and the specific particles further contain a polymerizable monomer

[0015] In particular, from the viewpoint of further improving the scratch resistance of the formed film, it is preferable that the specific particles contain a polymerizable monomer, and that the polymerizable group of the specific particles contains the polymerizable group of the polymerizable monomer. That is, the embodiment in which the specific particles have a polymerizable group is preferably the above-mentioned embodiment 2 or embodiment 3.

[0016] Since polymerizable monomers have high mobility during polymerization, it is believed that when the specific particles contain polymerizable monomers, the crosslink density increases, and the abrasion resistance of the film formed improves.

[0017] The resin having a polymerizable group and the polymerizable monomer will be described in detail below.

[0018] (Amino group A) The specific particles preferably further have an amino group A having a hydrogen atom on the carbon atom at the α-position (hereinafter also simply referred to as "amino group A").

[0019] Examples of the specific particles having the amino group A include the following. Aspect 1: Aspect in which the resin contained in the specific particles has an amino group A Aspect 2: Aspect in which the specific particles further contain a compound having an amino group A in addition to the resin and the photoradical generator Aspect 3: Aspect in which the resin contained in the specific particles has an amino group A, and the specific particles further contain a compound having an amino group A

[0020] In particular, from the viewpoint of further suppressing migration and further improving the scratch resistance of the film to be formed, it is preferable that the specific particles further contain a compound having an amino group A. That is, the embodiment in which the specific particles have an amino group A is preferably the above-mentioned embodiment 2 or embodiment 3.

[0021] When the specific particles have an amino group A, polymerization inhibition by oxygen is suppressed and polymerization of the particles having a polymerizable group proceeds efficiently, thereby suppressing migration and providing the formed film with excellent scratch resistance.

[0022] The resin having an amino group A and the compound having an amino group A will be described in detail later.

[0023] (Number of moles of amino group A relative to the total number of moles of photoradical generator) In the aqueous dispersion of the present disclosure, when the specific particles have an amino group A, the ratio of the number of moles of the amino group A to the total number of moles of the photoradical generator is preferably 5 mol% to 100 mol%, and more preferably 10 mol% to 80 mol%. When the ratio is 5 mol% or more, polymerization inhibition by oxygen is suppressed, and polymerization of the particles having polymerizable groups proceeds efficiently, thereby suppressing migration and providing excellent abrasion resistance to the formed film. On the other hand, when the ratio is 100 mol% or less, there are fewer unreacted amino groups in the reaction between the photoradical generator and the amino group, thereby suppressing migration. Furthermore, hydrolysis of other components by the amine in the ink is suppressed, resulting in excellent storage stability.

[0024] The number of moles of amino groups is measured by the following method.

[0025] Components other than the specific particles and water are removed from the aqueous dispersion to be measured to prepare an aqueous dispersion containing the specific particles. 50 g of the prepared aqueous dispersion is centrifuged at a rotation speed of 80,000 rpm (abbreviation of revolutions per minute) for 40 minutes. The supernatant liquid produced by centrifugation is removed, and the precipitate (specific particles) is collected. Approximately 0.5 g of the collected specific particles is weighed into container 1, and the weighed value W1 (g) is recorded. Next, 60 mL of acetic acid is added to dilute the weighed specific particles, thereby obtaining sample 1 for measuring the degree of neutralization. The obtained neutralization degree measurement sample 1 is titrated using a 0.1N (=0.1 mol / L) perchloric acid acetic acid solution as the titrant, and the volume of titrant required to reach the equivalence point is recorded as F1 (mL). Further, the titration is continued, and the volume of titrant required to reach the second equivalence point is recorded as F2 (mL). Here, "F1 (mL)" corresponds to the number of moles of acid groups neutralized with a strong base, and "(F2-F1) (mL)" corresponds to the number of moles of amino groups, which are weak bases.

[0026] (C=C valence) The polymerizable group of the specific particles preferably contains an ethylenic double bond, from the viewpoint of further improving the scratch resistance of the film to be formed. When the number of millimoles of ethylenic double bonds in 1 g of the specific particle is defined as the C=C value of the specific particle, the C=C value of the specific particle is preferably 0.30 mmol / g or more, more preferably 1.0 mmol / g or more, and even more preferably 2.0 mmol / g or more, from the viewpoint of further improving the abrasion resistance of the formed film. On the other hand, from the viewpoint of dispersion stability, the C═C value of the specific particles is preferably 6.0 mmol / g or less, more preferably 5.0 mmol / g or less, and even more preferably 4.0 mmol / g or less.

[0027] In the aqueous dispersion of the present disclosure, the total solid content of the specific particles is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, particularly preferably 80% by mass or more, and most preferably 85% by mass or more, relative to the total solid content of the aqueous dispersion. This further improves the scratch resistance of the film that is formed.

[0028] In the aqueous dispersion of the present disclosure, the total solid content of the specific particles is preferably 1% by mass to 50% by mass, more preferably 3% by mass to 40% by mass, and even more preferably 5% by mass to 30% by mass, relative to the total amount of the aqueous dispersion. When the total solid content of the specific particles is 1% by mass or more relative to the total amount of the aqueous dispersion, the scratch resistance of the formed film is further improved. Furthermore, when the total solid content of the specific particles is 50% by mass or less based on the total amount of the aqueous dispersion, the dispersion stability of the specific particles is further improved.

[0029] In the present disclosure, the total solid content of the specific particles means the total amount of the specific particles excluding the solvent (i.e., water and organic solvent). When the specific particles do not contain a solvent, the total solid content of the specific particles is the same as the total amount of the specific particles.

[0030] The volume average dispersed particle size of the specific particles in the aqueous dispersion is not particularly limited, but from the viewpoint of dispersion stability, it is preferably 0.01 μm to 10 μm, more preferably 0.01 μm to 5 μm, even more preferably 0.05 μm to 1 μm, particularly preferably 0.05 μm to 0.5 μm, and most preferably 0.05 μm to 0.3 μm.

[0031] In the present disclosure, the "volume average dispersed particle diameter" refers to a value measured by a light scattering method. The volume average dispersed particle diameter of specific particles is measured by a light scattering method using, for example, an LA-960 (Horiba, Ltd.).

[0032] <Resin> The specific particles contained in the aqueous dispersion contain at least one type of resin.

[0033] Examples of the resin include urethane polymer, urethane urea polymer, urea polymer, acrylic polymer, polyester, polyolefin, polystyrene, polycarbonate, and polyamide.

[0034] Here, the term "urethane polymer" refers to a polymer that contains a urethane bond but does not contain a urea bond, the term "urea polymer" refers to a polymer that contains a urea bond but does not contain a urethane bond, and the term "urethane-urea polymer" refers to a polymer that contains a urethane bond and a urea bond.

[0035] Further, the acrylic polymer refers to a polymer (homopolymer or copolymer) of raw material monomers containing at least one selected from the group consisting of acrylic acid, derivatives of acrylic acid (e.g., acrylic acid esters), methacrylic acid, and derivatives of methacrylic acid (e.g., methacrylic acid esters).

[0036] The resin preferably contains at least one of a urethane bond and a urea bond, U. In other words, the resin is preferably a urethane polymer, a urethane-urea polymer, or a urea polymer.

[0037] When the resin contains bonds U, the specific particles tend to interact with each other in the aqueous dispersion that has landed on the substrate due to interactions (e.g., hydrogen bonds) between the bonds U. This makes it easier for curing to proceed between the specific particles, further improving the scratch resistance of the film that is formed.

[0038] The bond U preferably contains a urethane bond. In other words, it is preferable that the resin contains a urethane bond and no urea bond, or contains a urethane bond and a urea bond.

[0039] (polymerizable group) The specific particles contained in the aqueous dispersion of the present disclosure have a polymerizable group. The polymerizable group of the specific particles may be a polymerizable group of a resin having a polymerizable group. That is, the resin contained in the specific particles may have a polymerizable group. As will be described later, when the specific particles contain a polymerizable monomer, the resin does not necessarily have to have a polymerizable group. Therefore, the resin does not necessarily have to have a polymerizable group. However, from the viewpoint of improving the scratch resistance of the film to be formed, the resin preferably has a polymerizable group.

[0040] The resin may contain only one type of polymerizable group, or may contain two or more types of polymerizable groups.

[0041] Whether the resin contains a polymerizable group can be confirmed, for example, by Fourier transform infrared spectroscopy (FT-IR) analysis.

[0042] The polymerizable group that can be contained in the resin is preferably a photopolymerizable group, and more preferably a photoradical polymerizable group.

[0043] The photoradical polymerizable group is preferably a (meth)acryloyl group, an allyl group, a styryl group, or a vinyl group, and from the viewpoint of radical polymerization reactivity and the hardness of the film formed, a (meth)acryloyl group is more preferable.

[0044] Among these, the polymerizable group that can be contained in the resin preferably contains an ethylenic double bond.

[0045] When the number of millimoles of ethylenic double bonds in 1 g of resin is defined as the C=C value of the resin, the C=C value of the resin is preferably 0.05 mmol or more, more preferably 0.10 mmol / g or more, even more preferably 0.30 mmol / g or more, and particularly preferably 0.50 mmol / g or more, from the viewpoint of further improving the hardness of the film to be formed.

[0046] On the other hand, from the viewpoint of dispersion stability, the C═C value of the resin is preferably 3.00 mmol / g or less, more preferably 2.50 mmol / g or less, even more preferably 2.00 mmol / g or less, and particularly preferably 1.50 mmol / g or less.

[0047] The resin may be a linear polymer or a cross-linked polymer. In the present disclosure, a linear polymer refers to a polymer that does not have a cross-linked structure, and a cross-linked polymer refers to a polymer that has a cross-linked structure. The chain polymer may have a cyclic structure or a branched structure. For specific particles containing chain polymers, see, for example, Japanese Patent No. 6584677.

[0048] A preferred embodiment of the specific particle when the resin is a crosslinked polymer is a microcapsule comprising a shell made of polymer P, which is a crosslinked polymer, and a core containing a polymerizable monomer. For specific particles containing crosslinked polymers, see, for example, Japanese Patent No. 6510681.

[0049] From the viewpoint of ejection properties, the resin is preferably a chain polymer that does not have a cross-linked structure.

[0050] In particular, the resin preferably contains a structural unit derived from an isocyanate compound and a structural unit derived from a compound containing an active hydrogen group. The resin of the above preferred embodiment contains a bond U formed by the reaction of an isocyanate group of an isocyanate compound with an active hydrogen group of a compound containing an active hydrogen group.

[0051] The active hydrogen group is preferably a hydroxy group, a primary amino group, or a secondary amino group. For example, the reaction of an isocyanate group with a hydroxy group forms a urethane group. Furthermore, a urea group is formed by the reaction of an isocyanate group with a primary amino group or a secondary amino group.

[0052] The isocyanate compound and the compound containing an active hydrogen group, which are raw materials for the resin having the above-described preferred structure, may be referred to as raw material compounds hereinafter. The isocyanate compound as the raw material compound may be one kind or two or more kinds. The compound containing an active hydrogen group as the raw material compound may be one kind or two or more kinds.

[0053] At least one of the isocyanate compounds used as raw material compounds is preferably a di- or higher functional isocyanate compound. As at least one of the compounds containing an active hydrogen group as the raw material compound, a compound containing two or more active hydrogen groups is preferred.

[0054] Among the raw material compounds, at least one of the isocyanate compound and the compound containing an active hydrogen group preferably contains an anionic group. This facilitates the production of a resin containing an anionic group. In this case, at least some of the anionic groups in the final resin may be groups obtained by neutralizing the anionic groups in the raw material compounds. In a more preferred embodiment, at least one of the compounds containing an active hydrogen group among the raw material compounds is a compound containing an active hydrogen group and an anionic group.

[0055] When the resin contains a polymerizable group, it is preferable that at least one of the isocyanate compound and the compound containing an active hydrogen group among the raw material compounds contains a polymerizable group, which makes it easy to produce the resin containing the polymerizable group. In a more preferred embodiment, at least one of the compounds containing an active hydrogen group among the raw material compounds is a compound containing an active hydrogen group and a polymerizable group.

[0056] When the resin is a chain polymer, the resin can be produced, for example, by reacting a difunctional isocyanate compound with a compound containing two active hydrogen groups. When the resin is a crosslinked polymer, the resin can be produced, for example, by reacting a tri- or higher functional isocyanate compound with a compound containing two or more active hydrogen groups. When the resin is a crosslinked polymer, the resin can also be produced, for example, by reacting a difunctional isocyanate compound with a compound containing three or more active hydrogen groups.

[0057] Preferred raw material compounds will be described below.

[0058] The isocyanate compound is preferably a difunctional or higher isocyanate compound, more preferably a difunctional to hexafunctional isocyanate compound.

[0059] When a bifunctional isocyanate compound is used as the raw material compound, the resin preferably contains the following structural unit (P1), which is a structural unit derived from the bifunctional isocyanate compound.

[0060] [ka]

[0061] In structural unit (P1), L 1 represents a divalent organic group having 1 to 20 carbon atoms, and * represents the bonding position.

[0062] L 1Specific examples of the above include residues obtained by removing two isocyanate groups (NCO groups) from the bifunctional isocyanate compounds according to the following specific examples.

[0063] Specific examples of the bifunctional isocyanate compound are as follows: However, the bifunctional isocyanate compound is not limited to the following specific examples.

[0064] [ka]

[0065] In addition, the bifunctional isocyanate compound may be a bifunctional isocyanate compound derived from the above specific examples, such as Duranate (registered trademark) D101, D201, and A101 (manufactured by Asahi Kasei Corporation).

[0066] In addition, the tri- or higher functional isocyanate compound is preferably a reaction product of at least one selected from the group consisting of bifunctional isocyanate compounds and at least one selected from the group consisting of compounds containing three or more active hydrogen groups (for example, tri- or higher functional polyol compounds, tri- or higher functional polyamine compounds, and tri- or higher functional polythiol compounds). The number of moles (number of molecules) of the bifunctional isocyanate compound to be reacted with the compound containing three or more active hydrogen groups is preferably 0.6 times or more, more preferably 0.6 to 5 times, even more preferably 0.6 to 3 times, and even more preferably 0.8 to 2 times the number of moles of the active hydrogen groups (number of equivalents of active hydrogen groups) in the compound containing three or more active hydrogen groups.

[0067] Examples of the bifunctional isocyanate compound for forming a trifunctional or higher isocyanate compound include the bifunctional isocyanate compounds according to the specific examples described above.

[0068] Examples of compounds containing three or more active hydrogen groups for forming a tri- or higher functional isocyanate compound include the compounds described in paragraphs 0057 to 0058 of WO 2016 / 052053.

[0069] Examples of the tri- or higher functional isocyanate compound include adduct-type tri- or higher functional isocyanate compounds, isocyanurate-type tri- or higher functional isocyanate compounds, and biuret-type tri- or higher functional isocyanate compounds. Commercially available adduct-type tri- or higher functional isocyanate compounds include Takenate (registered trademark) D-102, D-103, D-103H, D-103M2, P49-75S, D-110N, D-120N, D-140N, and D-160N (all manufactured by Mitsui Chemicals, Inc.), Desmodur (registered trademark) L75 and UL57SP (manufactured by Sumika Bayer Urethane Co., Ltd.), Coronate (registered trademark) HL, HX, and L (manufactured by Nippon Urethane Polymer Co., Ltd.), and P301-75E (manufactured by Asahi Kasei Corporation). Commercially available isocyanurate-type tri- or higher functional isocyanate compounds include Takenate (registered trademark) D-127N, D-170N, D-170HN, D-172N, and D-177N (all manufactured by Mitsui Chemicals, Inc.), Sumidur N3300, Desmodur (registered trademark) N3600, N3900, and Z4470BA (manufactured by Sumika Bayer Urethane Co., Ltd.), Coronate (registered trademark) HX and HK (manufactured by Nippon Urethane Polymer Co., Ltd.), and Duranate (registered trademark) TPA-100, TKA-100, TSA-100, TSS-100, TLA-100, and TSE-100 (manufactured by Asahi Kasei Corporation). Commercially available biuret-type tri- or higher functional isocyanate compounds include Takenate (registered trademark) D-165N and NP1100 (both manufactured by Mitsui Chemicals, Inc.), Desmodur (registered trademark) N3200 (manufactured by Sumika Bayer Urethane Co., Ltd.), and Duranate (registered trademark) 24A-100 (manufactured by Asahi Kasei Corporation).

[0070] At least one of the isocyanate compounds used as raw material compounds may be an isocyanate compound containing an anionic group. For details about isocyanate compounds containing an anionic group, see paragraphs

[0112] to

[0118] and

[0252] to

[0254] of WO 2016 / 052053. At least one of the isocyanate compounds used as raw material compounds may be an isocyanate compound containing a polymerizable group. For details about isocyanate compounds containing a polymerizable group, see paragraphs 0084 to 0089, 0203, and 0205 of WO 2016 / 052053.

[0071] The compound containing an active hydrogen group is preferably a compound containing two or more active hydrogen groups. The compound containing two or more active hydrogen groups is more preferably a polyol compound (that is, a compound having two or more hydroxy groups) or a polyamine compound (that is, a compound having two or more amino groups).

[0072] When a compound containing an active hydrogen group and an anionic group is used as the raw material compound, the polymer P preferably contains at least one of the following structural units (P0).

[0073] [ka]

[0074] In the structural unit (P0), L 0 represents a divalent organic group, * indicates the bond position, Y 1 and Y 2 each independently represents an oxygen atom, a sulfur atom, or -NR 1 represents a - group, R 1 represents a hydrogen atom or a hydrocarbon group having 1 to 10 carbon atoms, * indicates the bond position.

[0075] In structural unit (P0), L 0The divalent organic group represented by the formula (I) may be a group consisting of carbon atoms and hydrogen atoms, or may be a group containing carbon atoms and hydrogen atoms and also containing a heteroatom (for example, an oxygen atom, a nitrogen atom, a sulfur atom, etc.). L 0 Specific examples of the compound include residues obtained by removing two active hydrogen groups from the specific examples of compounds containing two or more active hydrogen groups described below.

[0076] R 1 is preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms. Y 1 and Y 2 each independently represents an oxygen atom or -NR 1 A - group is preferred, and an oxygen atom is more preferred.

[0077] Specific examples of diol compounds as compounds containing active hydrogen groups are shown below, but the compounds containing active hydrogen groups are not limited to the following specific examples.

[0078] [ka]

[0079] In compounds (12) to (15), nC7H 15 , nC9H 19 , nC 11 H 23 , and nC 17 H 35 represent a normal heptyl group, a normal nonyl group, a normal undecyl group, and a normal heptadecyl group, respectively. Compound (16) PPG is polypropylene glycol, and n is the repeating number. Compound (16-2) PEG is polyethylene glycol, and n is the number of repeating units. Compound (17) PEs is a polyester diol, n is the number of repeating units, and Ra and two Rb's are each independently a divalent hydrocarbon group having 2 to 25 carbon atoms. The n Ra's in compound (17) PEs may be the same or different. The (n+1) Rb's in compound (17) PEs may be the same or different. Compound (18) PCD is a polycarbonate diol, n is the number of repeating units, and (n+1) Rc's are each independently an alkylene group having 2 to 12 carbon atoms (preferably 3 to 8, more preferably 3 to 6). The (n+1) Rc's in compound (18) PC may be the same or different. Compound (19) PCL is polycaprolactone diol, where n and m each represent the number of repeats, and Rd represents an alkylene group having 2 to 25 carbon atoms.

[0080] Among these, the compounds containing an active hydrogen group are preferably the compounds (11) to (19) from the viewpoint of lowering the glass transition temperature of the resin.

[0081] When the resin has a polymerizable group, the compound containing an active hydrogen group also includes a compound containing an active hydrogen group and a polymerizable group. A compound containing an active hydrogen group and a polymerizable group is suitable as a compound for introducing a polymerizable group into a resin.

[0082] Specific examples of diol compounds as compounds containing an active hydrogen group and a polymerizable group are shown below, but the compounds containing an active hydrogen group and a polymerizable group are not limited to the following specific examples.

[0083] [ka]

[0084] For the compound containing an active hydrogen group and a polymerizable group, the description in paragraphs 0075 to 0089 of WO 2016 / 052053 may be referred to as appropriate.

[0085] The compound containing an active hydrogen group also includes a compound containing an active hydrogen group and an anionic group. A compound containing an active hydrogen group and an anionic group is suitable as a compound for introducing an anionic group into a resin.

[0086] When a compound containing an active hydrogen group and an anionic group is used as the raw material compound, the resin preferably contains the following structural unit (P2).

[0087] [ka]

[0088] In the structural unit (P2), L 21 represents a trivalent organic group having 1 to 20 carbon atoms, L 22 represents a single bond or a divalent organic group having 1 to 20 carbon atoms, A 1 represents a carboxy group, a salt of a carboxy group, a sulfo group, or a salt of a sulfo group, * indicates the bond position.

[0089] L 21 The trivalent organic group having 1 to 20 carbon atoms, represented by the following formula, preferably has 2 to 20 carbon atoms, more preferably has 3 to 20 carbon atoms, and further preferably has 4 to 20 carbon atoms. L 21 The trivalent organic group represented by the formula (I) is preferably a trivalent hydrocarbon group or a group in which at least one carbon atom in a trivalent hydrocarbon group has been replaced with a heteroatom (preferably an oxygen atom, a sulfur atom, or a nitrogen atom).

[0090] L 22 The divalent organic group having 1 to 20 carbon atoms, represented by the following formula, preferably has 1 to 10 carbon atoms, and more preferably has 1 to 6 carbon atoms. L 22The divalent organic group represented by the formula (I) is preferably a divalent hydrocarbon group (preferably an alkylene group) or a group in which at least one carbon atom in a divalent hydrocarbon group (preferably an alkylene group) has been substituted with an oxygen atom or a sulfur atom (preferably an oxygen atom). L 22 may be a single bond.

[0091] Specific examples of compounds containing an active hydrogen group and an anionic group are shown below, but the compounds containing an active hydrogen group and an anionic group are not limited to these examples. The carboxyl group and sulfo group in the following specific examples may be neutralized (i.e., may be a salt of the carboxyl group and a salt of the sulfo group), respectively.

[0092] [ka]

[0093] For compounds containing an active hydrogen group and an anionic group, the descriptions in paragraphs 0112 to 0118 and 0252 to 0254 of WO 2016 / 052053 can be referred to as appropriate.

[0094] (Amino group A) The resin contained in the specific particles may have an amino group A having a hydrogen atom on the carbon atom at the α-position. When the resin has an amino group A, inhibition of polymerization by oxygen is suppressed, and polymerization of the particles having a polymerizable group proceeds efficiently, which is thought to suppress migration and provide the formed film with excellent scratch resistance.

[0095] From the viewpoint of dispersion stability of the aqueous dispersion (i.e., dispersion stability of the specific particles), the resin preferably has a weight average molecular weight (Mw) of 5000 or more, more preferably 7000 or more, and even more preferably 8000 or more. The upper limit of Mw is not particularly limited, but examples thereof include 150,000, 100,000, 70,000, and 50,000.

[0096] In this disclosure, the number-average molecular weight and weight-average molecular weight are measured using gel permeation chromatography (GPC). For example, an HLC-8220GPC (manufactured by Tosoh Corporation) is used as the GPC, three TSKgel Super Multipore HZ-H columns (manufactured by Tosoh Corporation, 4.6 mm ID x 15 cm) are used as the columns, and THF (tetrahydrofuran) is used as the eluent. The conditions are a sample concentration of 0.45% by mass, a flow rate of 0.35 mL / min, a sample injection volume of 10 μL, a measurement temperature of 40°C, and detection using a refractive index (RI) detector. A calibration curve is prepared using eight standard samples of "TSK Standard Polystyrene" (manufactured by Tosoh Corporation) with product names "F-40," "F-20," "F-4," "F-1," "A-5000," "A-2500," "A-1000," and "n-propylbenzene."

[0097] The resin preferably has a glass transition temperature of 90° C. or lower, more preferably 70° C. or lower. The lower limit of the glass transition temperature is not particularly limited, and is, for example, −50° C.

[0098] When the glass transition temperature of the resin is 90°C or lower, the mobility of the resin is improved, thereby improving the reaction rate of the polymerization reaction. Furthermore, when the specific particles contain a polymerizable monomer, when the glass transition temperature of the resin is 90°C or lower, the mobility of the polymerizable monomer is improved, thereby improving the reaction rate of the polymerization reaction. As a result, migration is suppressed.

[0099] The glass transition temperature (Tg) of a resin means a value measured using differential scanning calorimetry (DSC). The glass transition temperature is specifically measured according to the method described in JIS K 7121 (1987) or JIS K 6240 (2011). The glass transition temperature in this disclosure is the extrapolated glass transition onset temperature (Tig). The glass transition temperature is measured by the following method. When determining the glass transition temperature, the temperature is maintained at approximately 50°C lower than the expected glass transition temperature of the resin until the apparatus stabilizes, and then the temperature is heated at a heating rate of 20°C / min to a temperature approximately 30°C higher than the temperature at which the glass transition ends, and a differential thermal analysis (DTA) curve or DSC curve is prepared. The extrapolated glass transition onset temperature (Tig) is determined as the temperature at the intersection of a straight line drawn by extending the low-temperature baseline of a DTA or DSC curve toward the high-temperature side and a tangent drawn at the point where the gradient of the curve in the step-like change portion of the glass transition is maximum. When the aqueous dispersion contains two or more resins, the glass transition temperature (Tg) of the resin means the weighted average value of the glass transition temperatures of the individual resins.

[0100] From the viewpoint of dispersion stability, the resin content is preferably 20% by mass to 95% by mass, more preferably 30% by mass to 90% by mass, and even more preferably 40% by mass to 85% by mass, based on the total solid content of the specific particles.

[0101] <Photoradical generator> The specific particles contained in the aqueous dispersion contain at least one type of photoradical generator.

[0102] A photoradical generator is a compound that generates radicals when irradiated with light.

[0103] Examples of the photoradical generator include an intramolecular cleavage-type photopolymerization initiator that causes intramolecular cleavage (sometimes simply referred to as a "cleavage-type photopolymerization initiator"), and an intramolecular hydrogen abstraction-type photopolymerization initiator that abstracts hydrogen from within the molecule (sometimes simply referred to as a "hydrogen abstraction-type photopolymerization initiator").

[0104] Examples of the intramolecular cleavage type photopolymerization initiator include alkylphenone-based photopolymerization initiators, acylphosphine oxide-based photopolymerization initiators, and oxime ester-based photopolymerization initiators. Among these, the intramolecular cleavage type photopolymerization initiator is preferably an acylphosphine oxide-based photopolymerization initiator.

[0105] Examples of the acylphosphine oxide compound include monoacylphosphine oxide compounds and bisacylphosphine oxide compounds, with bisacylphosphine oxide compounds being preferred.

[0106] Examples of the monoacylphosphine oxide compound include isobutyryldiphenylphosphine oxide, 2-ethylhexanoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide, o-toluyldiphenylphosphine oxide, pt-butylbenzoyldiphenylphosphine oxide, 3-pyridylcarbonyldiphenylphosphine oxide, acryloyldiphenylphosphine oxide, benzoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid vinyl ester, acryloyldiphenylphosphine oxide, benzo ... Examples of the diphenylphosphine oxide include dipoylbisdiphenylphosphine oxide, pivaloyldiphenylphosphine oxide, p-toluyldiphenylphosphine oxide, 4-(t-butyl)benzoyldiphenylphosphine oxide, terephthaloylbisdiphenylphosphine oxide, 2-methylbenzoyldiphenylphosphine oxide, versatoyldiphenylphosphine oxide, 2-methyl-2-ethylhexanoyldiphenylphosphine oxide, 1-methyl-cyclohexanoyldiphenylphosphine oxide, pivaloylphenylphosphinic acid methyl ester, and pivaloylphenylphosphinic acid isopropyl ester.

[0107] Examples of the bisacylphosphine oxide compound include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-ethoxyphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2-naphthylphosphine oxide, and bis(2,6-dichlorobenzoyl). Bis(2,6-dichlorobenzoyl)-4-chlorophenylphosphine oxide, Bis(2,6-dichlorobenzoyl)-2,4-dimethoxyphenylphosphine oxide, Bis(2,6-dichlorobenzoyl)decylphosphine oxide, Bis(2,6-dichlorobenzoyl)-4-octylphenylphosphine oxide, Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, Bis(2,4,6-trimethylbenzoyl)-2, 5-Dimethylphenylphosphine oxide, bis(2,6-dichloro-3,4,5-trimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichloro-3,4,5-trimethoxybenzoyl)-4-ethoxyphenylphosphine oxide, bis(2-methyl-1-naphthoyl)-2,5-dimethylphenylphosphine oxide, bis(2-methyl-1-naphthoyl)-4-ethoxyphenylphosphine oxide, bis(2-methyl-1-naphthoyl)-2- naphthylphosphine oxide, bis(2-methyl-1-naphthoyl)-4-propylphenylphosphine oxide, bis(2-methyl-1-naphthoyl)-2,5-dimethylphenylphosphine oxide, bis(2-methoxy-1-naphthoyl)-4-ethoxyphenylphosphine oxide, bis(2-chloro-1-naphthoyl)-2,5-dimethylphenylphosphine oxide and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0108] Among these, the acylphosphine oxide compound is preferably bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (product name "Omnirad 819", manufactured by IGM Resins BV), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (product name "Omnirad TPO H", manufactured by IGM Resins BV), or (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide (product name "Omnirad TPO-L", manufactured by IGM Resins BV).

[0109] Examples of the intramolecular abstraction type photopolymerization initiator include thioxanthone compounds.

[0110] Thioxanthone compounds include thioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dichlorothioxanthone, 2-dodecylthioxanthone, 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 1-methoxycarbonylthioxanthone, 2-ethoxycarbonylthioxanthone, 3-(2-methoxyethoxycarbonyl)thioxanthone, 4-butoxycarbonyl ...butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanthone, 4-butoxycarbonylthioxanth thioxanthone, 3-butoxycarbonyl-7-methylthioxanthone, 1-cyano-3-chlorothioxanthone, 1-ethoxycarbonyl-3-chlorothioxanthone, 1-ethoxycarbonyl-3-ethoxythioxanthone, 1-ethoxycarbonyl-3-aminothioxanthone, 1-ethoxycarbonyl-3-phenylsulfurylthioxanthone, 3,4-di[2-(2-methoxyethoxy)ethoxycarbonyl]thioxanthone, 1-ethoxycarbonyl-3-phenylsulfurylthioxanthone, thioxanthone, 2-methyl-6-dimethoxymethylthioxanthone, 2-methyl-6-(1,1-dimethoxybenzyl)thioxanthone, 2-morpholinomethylthioxanthone, 2-methyl-6-morpholinomethylthioxanthone, n-allylthioxanthone-3,4-dicarboximide, n-octylthioxanthone-3,4-dicarboximide, N-(1,1,3,3-tetramethylthioxanthone), methylbutyl)thioxanthone-3,4-dicarboximide, 1-phenoxythioxanthone, 6-ethoxycarbonyl-2-methoxythioxanthone, 6-ethoxycarbonyl-2-methylthioxanthone, thioxanthone-2-polyethylene glycol ester, and 2-hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthone-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride.

[0111] The thioxanthone compound may be a commercially available product, such as the SPEEDCURE series manufactured by Lambson (e.g., SPEEDCURE 7010, SPEEDCURE CPTX, SPEEDCURE ITX, etc.).

[0112] The intramolecular hydrogen abstraction photopolymerization initiator preferably has a number average molecular weight of 1000 or more. The upper limit of the number average molecular weight is not particularly limited, and is, for example, 3000. When the number average molecular weight is 1000 or more, the initiator is less likely to exude from the formed film, and migration is suppressed.

[0113] From the viewpoint of suppressing migration, the photoradical generator preferably contains both an intramolecular cleavage-type photopolymerization initiator and an intramolecular hydrogen abstraction-type photopolymerization initiator. In the photoradical generator, the mass ratio of the intramolecular cleavage-type photopolymerization initiator to the intramolecular hydrogen abstraction-type photopolymerization initiator (intramolecular cleavage-type photopolymerization initiator:intramolecular hydrogen abstraction-type photopolymerization initiator) is preferably 50:50 to 95:5, more preferably 70:30 to 90:10.

[0114] In the aqueous dispersion of the present disclosure, the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles is 4 mol% or more. When the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds is 4 mol% or more, the amount of radicals generated is large and the crosslinking density is improved, thereby suppressing migration and providing excellent scratch resistance to the formed film.

[0115] From the viewpoint of further suppressing migration and further improving the scratch resistance of the film formed, the ratio of the number of moles of photoradical generator to the number of moles of ethylenic double bonds is preferably 5 mol% to 40 mol%, more preferably 7 mol% to 30 mol%. When the ratio of the number of moles of photoradical generator to the number of moles of ethylenic double bonds is 40 mol% or less, the degree of polymerization is high and the crosslinking density is improved, thereby suppressing migration and providing the film formed with excellent scratch resistance.

[0116] In the aqueous dispersion of the present disclosure, the ratio of the number of moles of photoradical generator present as a solid to the total number of moles of photoradical generator in the particles is 5 mol% or less. A ratio of the number of moles of photoradical generator present as a solid to the total number of moles of photoradical generator of 5 mol% or less means that the proportion of solid-state photoradical generator in the particles is low. There is no particular restriction on the lower limit of this ratio, and it is preferable that the ratio is 0 mol%. In other words, it is preferable that the photoradical generator is present entirely as a liquid in the particles.

[0117] "The photoradical generator exists as a solid in the particles" means that the photoradical generator is not dissolved in the liquid contained in the particles. Therefore, in order to reduce the proportion of the photoradical generator existing as a solid in the particles, it is preferable to select a liquid that easily dissolves the radical generator as the liquid contained in the particles. Furthermore, it is preferable to select a photoradical generator that is liquid at 25°C as the photoradical generator.

[0118] The ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator can be calculated by the following method.

[0119] The amount of photoradical generator and the amount of liquid contained in the specific particles are measured, and the mass ratio of the photoradical generator to the liquid is calculated. The photoradical generator and the liquid are mixed at the calculated mass ratio under conditions of 25°C and stirred. The amount of photoradical generator that does not dissolve in the liquid is measured. The ratio of the number of moles of photoradical generator that does not dissolve in the liquid to the total number of moles of photoradical generator mixed with the liquid is calculated.

[0120] From the viewpoint of dispersion stability, the content of the photoradical generator is preferably 4% by mass to 30% by mass, more preferably 5% by mass to 25% by mass, and even more preferably 6% by mass to 20% by mass, relative to the total solid content of the specific particles.

[0121] -HSP distance between resin and photoradical generator- In the aqueous dispersion of the present disclosure, the HSP distance between the resin and the photoradical generator is 5.5 MPa. 1 / 2 Preferably, it is 4.5 MPa or less. 1 / 2 The lower limit of the HSP distance is not particularly limited, and is, for example, 0.1 MPa. 1 / 2 is.

[0122] The above HSP distance is 5.5MPa 1 / 2 When the content is equal to or less than this, the compatibility between the resin and the photoradical generator is high, and the storage stability is excellent.

[0123] Specifically, the HSP distance is a value calculated by the following formula (X1).

[0124] HSP distance = Σ(ΔHSP(R k -P i )×m k ×m i ) … Formula (X1)

[0125] In formula (X1), k and i each independently represent an integer of 1 or more, m k represents the mass fraction of the kth photoradical generator relative to the total amount of photoradical generators contained in the aqueous dispersion (i.e., a value greater than 0 and less than 1), m i represents the mass fraction of the i-th resin relative to the total amount of resins contained in the aqueous dispersion (i.e., a value greater than 0 and less than 1), ΔHSP(R k -P i ) represents the HSP distance between the kth photoradical generator and the ith resin.

[0126] The HSP distance is a value that correlates with the compatibility of two substances to be compared (hereinafter referred to as substance 1 and substance 2). The smaller the HSP distance, the higher the compatibility between substance 1 and substance 2.

[0127] The HSP distance is calculated by applying δD (dispersion term) (hereinafter referred to as δD1 and δD2), δP (polarization term) (hereinafter referred to as δP1 and δP2), and δH (hydrogen bond term) (hereinafter referred to as δH1 and δH2) of each of substance 1 and substance 2 to the following formula (A).

[0128] Here, δD (dispersion term), δP (polarization term), and δH (hydrogen bonding term) are the three parameters that make up the HSP (i.e., Hansen Solubility Parameter).

[0129] For example, ΔHSP(R k -P i ) is calculated by substituting the dispersion term of the kth photoradical generator as δD1, the polarization term of the kth photoradical generator as δP1, the hydrogen bond term of the kth photoradical generator as δH1, the dispersion term of the ith resin as δD2, the polarization term of the ith resin as δP2, and the hydrogen bond term of the ith resin as δH2 into the following formula (A):

[0130]

number

[0131] The dispersion term (hereinafter referred to as "δD(resin i)"), polarization term (hereinafter referred to as "δP(resin i)"), and hydrogen bond term (hereinafter referred to as "δH(resin i)") for the i-th resin are determined based on the method of KWSUH and JMCORBETT described in Journal of Applied Polymer Science, 12, p. 2359 (1968).

[0132] Specifically, ΔD(resin i), ΔP(resin i), and ΔH(resin i) are determined by the following method. 500 mg of a sample (i.e., resin i) is completely dissolved in 10 mL of tetrahydrofuran (THF), and deionized water is added dropwise to the resulting solution until the solution becomes cloudy. The volume fraction [deionized water / (deionized water + THF)] at which the solution becomes cloudy is defined as Vw. 500 mg of a sample (i.e., resin i) is completely dissolved in 10 mL of tetrahydrofuran (THF), and hexane is added dropwise to the resulting solution until the solution becomes cloudy. The volume fraction [hexane / (hexane + THF)] at which the solution becomes cloudy is defined as Vh. Using the obtained Vw and Vh, ΔD(resin i), ΔP(resin i), and ΔH(resin i) are determined by the following formulas (D1), (P1), and (H1), respectively.

[0133] δD (resin i) = [Vw 1 / 2 ×δD(W / T)+Vh 1 / 2 ×δD(H / T)) / 〔Vw 1 / 2 +Vh 1 / 2 〕… Formula (D1) δP(resin i) = [Vw 1 / 2 ×δP(W / T)+Vh 1 / 2 ×δP(H / T) / [Vw 1 / 2 +Vh 1 / 2 )... Formula (P1) δH (resin i) = [Vw 1 / 2 ×δH(W / T)+Vh 1 / 2 ×δH(H / T)) / 〔Vw 1 / 2 +Vh 1 / 2 )... Formula (H1)

[0134] In the formula (D1), the following parameters are values ​​calculated by the following formulas: δD(W / T) =δD(THF)×(1-Vw)+δD(water)×Vw δD(H / T) =δD(THF)×(1-Vh)+δD(hexane)×Vh δP(W / T) =δP(THF)×(1-Vw)+δP(water)×Vw δP(H / T) =δP(THF)×(1-Vh)+δP(hexane)×Vh δH(W / T) =δH(THF)×(1-Vw)+δH(water)×Vw δH(H / T) =δH(THF)×(1-Vh)+δH(hexane)×Vh

[0135] In the above formula, the following numerical values ​​are used as the following parameters: δD(THF) = 16.8 δD(water) = 15.5 δD(hexane)=14.9 δP(THF) = 5.7 δP(water) = 16 δP(hexane)=0 δH(THF) = 8 δH(water) = 42.3 δH(hexane)=0

[0136] The dispersion term, polarization term, and hydrogen bonding term in the radical generator are calculated in the same manner as the dispersion term, polarization term, and hydrogen bonding term in the resin.

[0137] The specific particles contained in the aqueous dispersion may contain components other than the resin and the photoradical generator.

[0138] <Polymerizable monomer> The specific particles preferably contain at least one type of polymerizable monomer. In the present disclosure, the term "polymerizable monomer" refers to a monomer having a polymerizable group but not having an amino group A, and is distinguished from a compound having an amino group A.

[0139] The polymerizable monomer bonds specific particles together when the aqueous dispersion applied to the substrate is cured, thereby contributing to improving the scratch resistance of the film formed.

[0140] As the polymerizable monomer contained in the specific particles, the compounds described in paragraphs 0097 to 0105 of WO 2016 / 052053 may be used.

[0141] The polymerizable monomer that can be contained in the specific particles is preferably a photopolymerizable monomer, and more preferably a photoradical polymerizable monomer. A photopolymerizable monomer is a compound that has the property of being polymerized when irradiated with light.

[0142] The molecular weight of the polymerizable monomer is preferably 100 to 4,000, more preferably 100 to 2,000, even more preferably 100 to 1,000, even more preferably 100 to 900, still more preferably 100 to 800, and particularly preferably 150 to 750.

[0143] The molecular weight of the polymerizable monomer can be calculated based on the type and number of elements constituting the polymerizable monomer.

[0144] The preferred embodiments of the polymerizable group contained in the polymerizable monomer are the same as the preferred embodiments of the polymerizable group that can be contained in the resin.

[0145] The photopolymerizable monomer is preferably a compound containing an ethylenic double bond.

[0146] Photopolymerizable monomers include acrylate compounds, methacrylate compounds, styrene compounds, vinyl naphthalene compounds, N-vinyl heterocyclic compounds, unsaturated polyesters, unsaturated polyethers, unsaturated polyamides, and unsaturated urethanes.

[0147] Examples of acrylate compounds include 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, tridecyl acrylate, 2-phenoxyethyl acrylate (PEA), bis(4-acryloxypolyethoxyphenyl)propane, oligoester acrylate, epoxy acrylate, isobornyl acrylate (IBOA), dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentanyl acrylate, cyclic trimethylolpropane formal acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, 2-(2-vinyloxyethoxy)ethyl acrylate, octyl acrylate, decyl acrylate, isodecyl acrylate, lauryl acrylate, and 3,3,5-trimethylcyclohexyl acrylate. monofunctional acrylate compounds such as acrylate, 4-t-butylcyclohexyl acrylate, isoamyl acrylate, stearyl acrylate, isostearyl acrylate, 2-ethylhexyl diglycol acrylate, 2-hydroxybutyl acrylate, 2-acryloyloxyethyl hydrophthalic acid, ethoxydiethylene glycol acrylate, methoxydiethylene glycol acrylate, methoxypolyethylene glycol acrylate, methoxypropylene glycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, vinyl ether acrylate, 2-acryloyloxyethyl succinic acid, 2-acryloyloxyphthalic acid, 2-acryloxyethyl-2-hydroxyethyl phthalic acid, lactone-modified acrylate, acryloylmorpholine, acrylamide, and substituted acrylamides (e.g., N-methylolacrylamide and diacetone acrylamide);

[0148] Polyethylene glycol diacrylate, polypropylene glycol diacrylate, polytetramethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate (HDDA), 1,9-nonanediol diacrylate (NDDA), 1,10-decanediol diacrylate (DDDA), 3-methylpentanediol diacrylate (3MPDDA), neopentyl glycol diacrylate, tricyclodecane dimethanol diacrylate, bisphenol A ethylene oxide (EO) adduct diacrylate, bisphenol A propylene oxide (PO) adduct diacrylate, ethoxylated bisphenol A diacrylate, hydrochloric acid, bifunctional acrylate compounds such as xyneopentyl glycol diacrylate, propoxylated neopentyl glycol diacrylate, alkoxylated dimethyloltricyclodecane diacrylate, polytetramethylene glycol diacrylate, alkoxylated cyclohexanone dimethanol diacrylate, alkoxylated hexanediol diacrylate, dioxane glycol diacrylate, cyclohexanone dimethanol diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, tetraethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate (TPGDA), and neopentyl glycol propylene oxide adduct diacrylate;

[0149] Trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol tetraacrylate, ethoxylated isocyanuric acid triacrylate, ε-caprolactone-modified tris-(2-acryloxyethyl) isocyanurate, ditrimethylolpropane tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, caprolactone Examples of the acrylate compound include tri- or higher functional acrylate compounds such as caprolactam-modified trimethylolpropane triacrylate, pentaerythritol tetraacrylate, pentaerythritol ethoxy tetraacrylate, glycerin propoxy triacrylate, ethoxylated dipentaerythritol hexaacrylate, caprolactam-modified dipentaerythritol hexaacrylate, propoxylated glycerin triacrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate.

[0150] Examples of the methacrylate compound include monofunctional methacrylate compounds such as methyl methacrylate, n-butyl methacrylate, allyl methacrylate, glycidyl methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, methoxypolyethylene glycol methacrylate, methoxytriethylene glycol methacrylate, hydroxyethyl methacrylate, phenoxyethyl methacrylate, and cyclohexyl methacrylate;

[0151] Examples include bifunctional methacrylate compounds such as polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2-bis(4-methacryloxypolyethoxyphenyl)propane, and tetraethylene glycol dimethacrylate.

[0152] Examples of the styrene compound include styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, and p-methoxy-β-methylstyrene.

[0153] Examples of the vinylnaphthalene compound include 1-vinylnaphthalene, methyl-1-vinylnaphthalene, β-methyl-1-vinylnaphthalene, 4-methyl-1-vinylnaphthalene, and 4-methoxy-1-vinylnaphthalene.

[0154] Examples of N-vinyl heterocyclic compounds include N-vinylcarbazole, N-vinylpyrrolidone, N-vinylethylacetamide, N-vinylpyrrole, N-vinylphenothiazine, N-vinylacetanilide, N-vinylethylacetamide, N-vinylsuccinimide, N-vinylphthalimide, N-vinylcaprolactam, and N-vinylimidazole.

[0155] Other polymerizable monomers include allyl glycidyl ether, diallyl phthalate, triallyl trimellitate, and N-vinylamides such as N-vinylformamide.

[0156] In particular, from the viewpoint of further improving the adhesion between the film and the substrate, the polymerizable monomer that can be contained in the specific particles preferably contains a polymerizable monomer having a cyclic structure.

[0157] Examples of monofunctional polymerizable monomers having a cyclic structure include 2-phenoxyethyl acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, isobornyl acrylate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentanyl acrylate, ethoxylated isocyanuric acid triacrylate, and ε-caprolactone-modified tris-(2-acryloxyethyl)isocyanurate.

[0158] Furthermore, examples of bifunctional polymerizable monomers having a cyclic structure include tricyclodecane dimethanol di(meth)acrylate, bisphenol A ethylene oxide (EO) adduct di(meth)acrylate, bisphenol A propylene oxide (PO) adduct di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, alkoxylated dimethylol tricyclodecane di(meth)acrylate, alkoxylated cyclohexanone dimethanol di(meth)acrylate, and cyclohexanone dimethanol di(meth)acrylate.

[0159] In addition to the polymerizable monomers listed above, commercially available products described in Yamashita Shinzo (ed.), "Crosslinking Agent Handbook" (Taiseisha, 1981); Kato Kiyomi (ed.), "UV / EB Curing Handbook (Raw Materials Edition)" (Kobunshi Kankokai, 1985); RadTech Research Group (ed.), "Applications and Markets of UV / EB Curing Technology," p. 79 (CMC, 1989); Takiyama Eiichiro (ed.), "Polyester Resin Handbook" (Nikkan Kogyo Shimbun, 1988), and the like, as well as radical polymerizable monomers known in the industry, can be used.

[0160] Furthermore, as the photopolymerizable monomer, photocurable polymerizable monomers used in the photopolymerizable compositions described in JP-A-7-159983, JP-B-7-31399, JP-A-8-224982, JP-A-10-863, JP-A-9-134011, JP-T-2004-514014, and the like are known, and these can also be used as the polymerizable monomer that can be contained in the specific particles.

[0161] As the photopolymerizable monomer, a commercially available product may be used. Examples of commercially available photopolymerizable monomers include AH-600 (bifunctional), AT-600 (bifunctional), UA-306H (hexafunctional), UA-306T (hexafunctional), UA-306I (hexafunctional), UA-510H (decafunctional), UF-8001G (bifunctional), DAUA-167 (bifunctional), Light Acrylate NPA (bifunctional), Light Acrylate 3EG-A (bifunctional) (all from Kyoeisha Chemical Co., Ltd.), and SR33 9A (PEA, monofunctional), SR506 (IBOA, monofunctional), CD262 (bifunctional), SR238 (HDDA, bifunctional), SR341 (3MPDDA, bifunctional), SR508 (bifunctional), SR306H (bifunctional), CD560 (bifunctional), SR833S (bifunctional), SR444 (trifunctional), SR454 (trifunctional), SR492 (trifunctional), SR499 (trifunctional), CD501 (trifunctional), SR502 ( Trifunctional), SR9020 (trifunctional), CD9021 (trifunctional), SR9035 (trifunctional), SR494 (tetrafunctional), SR399E (pentafunctional) (all from Sartomer), A-NOD-N (NDDA, bifunctional), A-DOD-N (DDDA, bifunctional), A-200 (bifunctional), APG-400 (bifunctional), A-BPE-10 (bifunctional), A-BPE-20 (bifunctional), A-9300 (trifunctional), A-9300-1CL (trifunctional), A-TMPT (trifunctional), A-TMM-3L (trifunctional), A-TMMT (tetrafunctional), AD-TMP (tetrafunctional) (all from Shin-Nakamura Chemical Co., Ltd.), UV-7510B (trifunctional) (Nippon Synthetic Chemical Industry Co., Ltd.), KAYARAD DPCA-30 (hexafunctional), KAYARAD DPEA-12 (hexafunctional) (both manufactured by Nippon Kayaku Co., Ltd.), and the like. Other commercially available polymerizable monomers that can be suitably used include NPGPODA (neopentyl glycol propylene oxide adduct diacrylate), SR531, SR285, and SR256 (all manufactured by Sartomer Corporation), A-DHP (dipentaerythritol hexaacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd.), Aronix (registered trademark) M-156 (manufactured by Toagosei Co., Ltd.), V-CAP (manufactured by BASF), and Viscoat #192 (manufactured by Osaka Organic Chemical Industry Co., Ltd.).

[0162] The content of the polymerizable monomer is preferably 5% by mass to 75% by mass, more preferably 10% by mass to 65% by mass, even more preferably 15% by mass to 55% by mass, and particularly preferably 20% by mass to 50% by mass, based on the total solid content of the specific particles.

[0163] <Compounds containing amino group A> The specific particles preferably contain at least one compound having an amino group A having a hydrogen atom on the carbon atom at the α-position.

[0164] The compound having an amino group A has a molecular weight of 1000 or less and is distinguished from the resin having an amino group A described above.

[0165] When the specific particles contain a compound having an amino group A, polymerization inhibition by oxygen is suppressed and polymerization of the particles having a polymerizable group proceeds efficiently, thereby suppressing migration and providing the formed film with excellent scratch resistance.

[0166] In the particles, the ratio of the number of moles of the compound having an amino group present as a solid to the total number of moles of the compound having an amino group A is preferably 5 mol% or less. There is no particular restriction on the lower limit of this ratio, and the ratio is preferably 0 mol%. In other words, it is preferable that the compound having an amino group A is present entirely as a liquid within the particles.

[0167] "The compound having an amino group A exists as a solid in the particles" means that the compound having an amino group A is not dissolved in the liquid contained in the particles. Therefore, in order to reduce the proportion of the compound having an amino group A existing as a solid in the particles, it is preferable to select a liquid that easily dissolves the compound having an amino group A as the liquid contained in the particles. Furthermore, it is preferable to select a compound that is liquid at 25°C as the compound having an amino group A.

[0168] The ratio of the number of moles of the compound having an amino group present as a solid to the total number of moles of the compound having an amino group A can be calculated in the same manner as the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator.

[0169] In the compound having the amino group A, the number of amino groups A is preferably 1 to 6, more preferably 1 to 3, and even more preferably 1 or 2.

[0170] From the viewpoint of further suppressing migration, the compound having the amino group A preferably further has a polymerizable group, and more preferably has a (meth)acryloyl group.

[0171] The compound having an amino group A may be a commercially available product. Commercially available products include: LA-52, LA-63P, LA-72 (all manufactured by ADEKA); CN371 (both manufactured by Sartomer); and Exacure A198, Omnirad 907, Omnirad 369, Omnirad379, Omnipol ASA, Omnipol 910 (manufactured by IGM Resins BV) Examples include:

[0172] The content of the compound having an amino group A is preferably 0.1% by mass to 12% by mass, more preferably 0.5% by mass to 10% by mass, based on the total solid content of the specific particles.

[0173] -HSP distance between photoradical generator and compound containing amino group A- In the aqueous dispersion of the present disclosure, the HSP distance between the photoradical generator and the compound having an amino group A is 6 MPa. 1 / 2 Preferably, it is 5 MPa or less. 1 / 2 The lower limit of the HSP distance is not particularly limited, and is, for example, 0.1 MPa. 1 / 2 is.

[0174] The above HSP distance is 6MPa 1 / 2 When the content is equal to or less than this, the reactivity between the photoradical generator and the compound having the amino group A is improved, and therefore migration is further suppressed.

[0175] The HSP distance between the photoradical generator and the compound having the amino group A is calculated in the same manner as the calculation method for the HSP distance between the resin and the photoradical generator.

[0176] <Other ingredients> The specific particles may contain other components in addition to the above components, such as an organic solvent.

[0177] The specific particles preferably contain a component that is liquid at 25°C (hereinafter also referred to as "liquid component"). The liquid component may be a photoradical generator or a polymerizable monomer. From the viewpoint of promoting a polymerization reaction within the particles, the content of the liquid component is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, relative to the total solid content of the specific particles. From the viewpoint of suppressing elution of the liquid component outside the particles and improving storage stability, the content of the liquid component is preferably 75% by mass or less, more preferably 65% ​​by mass or less, and even more preferably 55% by mass or less, relative to the total solid content of the specific particles.

[0178] Furthermore, from the viewpoint of suppressing the elution of the liquid component outside the particles and improving storage stability, the ClogP value of the liquid component is preferably 1.5 or more, more preferably 2.0 or more, and even more preferably 3.0 or more.

[0179] In the present disclosure, the ClogP value is calculated using the fragment method, and ChemDraw Professional 16 is used as the calculation software using the fragment method.

[0180] [water] The aqueous dispersion of the present disclosure contains water. Water is a dispersion medium for specific particles (dispersoids). The water content is not particularly limited, but is preferably 10% by mass or more, more preferably 20% by mass or more, even more preferably 30% by mass or more, and particularly preferably 50% by mass or more, based on the total amount of the aqueous dispersion. The water content is preferably 99% by mass or less, more preferably 95% by mass or less, and even more preferably 90% by mass or less, based on the total amount of the aqueous dispersion.

[0181] [Other ingredients] The aqueous dispersion of the present disclosure may contain other components in addition to the specific particles and water. Examples of the other components include a colorant and a water-soluble organic solvent. The aqueous dispersion of the present disclosure may also contain other components such as surfactants, polymerization inhibitors, and ultraviolet absorbers, which are additives commonly added to inks. The other components may or may not be contained in the specific particles.

[0182] Furthermore, the aqueous dispersion of the present disclosure may contain, outside the specific particles, a water-soluble polymerizable monomer, a water-soluble photoradical generator, a water-soluble resin, etc. For details about these components, see, for example, paragraphs 0134 to 0157 of WO 2016 / 052053.

[0183] When the aqueous dispersion of the present disclosure contains a colorant, it is preferable that the aqueous dispersion of the present disclosure contains the colorant outside the specific particles (that is, the specific particles do not contain the colorant). The coloring material is not particularly limited, and can be arbitrarily selected from known coloring materials such as pigments, water-soluble dyes, disperse dyes, etc. Among these, it is more preferable to include a pigment in view of excellent weather resistance and excellent color reproducibility.

[0184] The pigment is not particularly limited and can be appropriately selected depending on the purpose. Examples include known organic pigments and inorganic pigments, as well as resin particles dyed with a dye, commercially available pigment dispersions, and surface-treated pigments (for example, pigments dispersed in water, a liquid compound, an insoluble resin, or the like as a dispersion medium, and pigments whose surfaces have been treated with a resin, a pigment derivative, or the like). Examples of organic pigments and inorganic pigments include yellow pigments, red pigments, magenta pigments, blue pigments, cyan pigments, green pigments, orange pigments, purple pigments, brown pigments, black pigments, and white pigments.

[0185] When a pigment is used as the coloring material, a pigment dispersant may be used as necessary. When a pigment is used as the coloring material, a self-dispersing pigment having a hydrophilic group on the surface of the pigment particle may be used. For colorants and pigment dispersants, reference can be made as appropriate to paragraphs 0180 to 0200 of JP-A No. 2014-040529 and paragraphs 0122 to 0129 of WO 2016 / 052053.

[0186] When the aqueous dispersion of the present disclosure contains a colorant, the content of the colorant is preferably 0.1% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, and particularly preferably 0.5% by mass to 5% by mass, relative to the total amount of the aqueous dispersion.

[0187] The aqueous dispersion of the present disclosure can be suitably used as an inkjet ink.

[0188] A preferred embodiment of the present disclosure is an inkjet ink containing water and particles that contain a resin and a photoradical generator and have a polymerizable group, wherein the polymerizable group contains an ethylenic double bond, and the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles is 4 mol % or more, and the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator is 5 mol % or less.

[0189] When the aqueous dispersion of the present disclosure is used as an inkjet ink, from the viewpoint of improving ejection properties, the aqueous dispersion of the present disclosure preferably contains a water-soluble organic solvent outside the specific particles.

[0190] Here, "water-soluble" refers to the property of dissolving more than 1 g in 100 g of distilled water at 25°C.

[0191] When the aqueous dispersion of the present disclosure contains a water-soluble organic solvent, the content of the water-soluble organic solvent is preferably 0.1% by mass to 30% by mass, and more preferably 1.0% by mass to 20% by mass, relative to the total amount of the aqueous dispersion.

[0192] Specific examples of the water-soluble organic solvent are as follows: Alcohols (e.g., methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol, etc.) Polyhydric alcohols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, 2-methylpropanediol, etc.) Polyhydric alcohol ethers (e.g., ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, tripropylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, ethylene glycol monophenyl ether, propylene glycol monophenyl ether, etc.) Amines (e.g., ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenediamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine, pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.) Amides (e.g., formamide, N,N-dimethylformamide, N,N-dimethylacetamide, etc.) Heterocyclic compounds (e.g., 2-pyrrolidone, N-methyl-2-pyrrolidone, cyclohexylpyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-imidazolidinone, γ-butyrolactone, etc.) Sulfoxide compounds (e.g., dimethyl sulfoxide, etc.) Sulfones (e.g., sulfolane, etc.) Others (urea, acetonitrile, acetone, etc.)

[0193] [Application] The aqueous dispersion of the present disclosure can be used in a variety of applications. The aqueous dispersion of the present disclosure can be used, for example, as an ink such as an inkjet ink or a composition for forming a coating film. In particular, the aqueous dispersion of the present disclosure is suitably used as an inkjet ink.

[0194] [Method for producing aqueous dispersion] The method for producing the aqueous dispersion of the present disclosure is not particularly limited.

[0195] The method for producing the aqueous dispersion includes, for example, a step of mixing an oil phase component containing an organic solvent, a resin, and a photoradical generator with an aqueous phase component containing water, and emulsifying the mixture to obtain an aqueous dispersion of specific particles.

[0196] In the step of obtaining an aqueous dispersion of specific particles, the oil phase component and the aqueous phase component are mixed and the resulting mixture is emulsified to form specific particles. The formed specific particles function as dispersoids in the produced aqueous dispersion. The water in the aqueous phase component functions as a dispersion medium in the aqueous dispersion to be produced.

[0197] Examples of organic solvents contained in the oil phase component include ethyl acetate and methyl ethyl ketone. It is preferable that at least a part of the organic solvent is removed during the process of forming the specific particles and after the formation of the specific particles.

[0198] The oil phase component may contain, in addition to the above components, for example, a polymerizable monomer and a compound having an amino group A.

[0199] The aqueous phase component is not particularly limited except that it contains water. The aqueous phase component may contain a neutralizing agent for neutralizing at least a portion of the hydrophilic groups of the resin. Neutralizing agents include alkali metal hydroxides (eg, sodium hydroxide, potassium hydroxide, etc.) and organic amines (eg, triethylamine, etc.). The aqueous phase components may contain components other than water and a neutralizing agent.

[0200] In the production process for the aqueous dispersion, the total amount of the oil phase component and the aqueous phase component excluding the organic solvent and water corresponds to the total solid content of the specific particles in the produced aqueous dispersion. For preferred ranges of the amount of each component that can be used in the method for producing the aqueous dispersion, see the above-mentioned section "Specific particles." In this reference, the terms "content" and "total solid content of specific particles" in the above-mentioned section "Specific particles" are to be read as "amount used" and "total amount of oil phase components and aqueous phase components excluding organic solvents and water," respectively.

[0201] In the step of obtaining an aqueous dispersion of specific particles, the method for mixing the oil phase component and the aqueous phase component is not particularly limited, but may be, for example, mixing by stirring.

[0202] In the step of obtaining an aqueous dispersion of specific particles, the emulsification method is not particularly limited, but examples thereof include emulsification using an emulsifying device such as a homogenizer (for example, a disperser). The rotation speed of the disperser during emulsification is, for example, 5,000 rpm to 20,000 rpm, and preferably 10,000 rpm to 15,000 rpm. The rotation time for emulsification is, for example, 1 minute to 120 minutes, preferably 3 minutes to 60 minutes, more preferably 3 minutes to 30 minutes, and even more preferably 5 minutes to 15 minutes.

[0203] The emulsification in the step of obtaining the aqueous dispersion of the specific particles may be carried out under heating. By carrying out the emulsification under heating, the specific particles can be formed more efficiently. Furthermore, by carrying out the emulsification under heating, at least a portion of the organic solvent in the oil phase component can be easily removed from the mixture. When emulsification is carried out under heating, the heating temperature is preferably 35°C to 70°C, and more preferably 40°C to 60°C.

[0204] Furthermore, the process of obtaining an aqueous dispersion of specific particles may include an emulsification process of emulsifying the mixture (for example, at a temperature below 35°C) and a heating process of heating the emulsion obtained by the emulsification process (for example, at a temperature of 35°C or higher). In an embodiment in which the step of obtaining an aqueous dispersion of specific particles includes an emulsification step and a heating step, the specific particles can be formed more efficiently, particularly in the heating step. Furthermore, in an embodiment in which the step of obtaining an aqueous dispersion of specific particles includes an emulsification step and a heating step, at least a portion of the organic solvent in the oil phase component is easily removed from the mixture, particularly in the heating step. The heating temperature in the heating step is preferably 35°C to 70°C, more preferably 40°C to 60°C. The heating time in the heating step is preferably 6 to 50 hours, more preferably 12 to 40 hours, and even more preferably 15 to 35 hours.

[0205] Furthermore, the method for producing the aqueous dispersion may include other steps in addition to the step of obtaining the aqueous dispersion of the specific particles, as necessary. Other steps include a step of adding other components (coloring materials, etc.) after the step of obtaining an aqueous dispersion of specific particles.

[0206] [Membrane formation method] A preferred embodiment of the film formation method using the aqueous dispersion of the present disclosure described above (hereinafter also referred to as "film formation method X") is as follows. The film forming method X includes a step of applying the aqueous dispersion of the present disclosure onto a substrate (hereinafter also referred to as an "application step"); a step of curing the aqueous dispersion applied to the substrate (hereinafter also referred to as a "curing step"); Includes. The film forming method X may include other steps as necessary. According to the film forming method X, a film having excellent abrasion resistance and excellent adhesion to the substrate is formed.

[0207] <Base material> The substrate used in the film-forming method X is not particularly limited, and may be either a non-permeable substrate or a permeable substrate, but is preferably a non-permeable substrate. Specifically, when a film is formed on a non-permeable substrate using an aqueous composition, there is a strong demand for improved abrasion resistance and adhesion of the film, and therefore, when a non-permeable substrate is used as the substrate in the film-forming method X, such demands can be satisfied. Here, the impermeable substrate is a substrate that has a water absorption rate (unit: mass) according to ASTM D570, an ASTM test method. This refers to a substrate with a % content (measurement time: 24 hours) of less than 10. The water absorption rate of the impermeable substrate is preferably 5 or less.

[0208] Examples of impermeable substrates include: Examples of the material include paper laminated with plastic (e.g., polyethylene, polypropylene, polystyrene, etc.), metal plates (e.g., plates of metals such as aluminum, zinc, copper, etc.), plastic films (e.g., films of polyvinyl chloride (PVC) resin, cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate (PET), polyethylene (PE), polystyrene (PS), polypropylene (PP), polycarbonate (PC), polyvinyl acetal, acrylic resin, etc.), paper laminated with or vapor-deposited with the above-mentioned metals, plastic films laminated with or vapor-deposited with the above-mentioned metals, and leather.

[0209] Examples of leather include natural leather (also called "genuine leather"), synthetic leather (for example, PVC (polyvinyl chloride) leather, PU (polyurethane) leather), etc. For more information on leather, see, for example, paragraphs 0163 to 0165 of JP 2009-058750 A. For example, when a film is formed on an impermeable substrate such as leather (e.g., vehicle seats, bags, shoes, wallets, etc.) or plastic film, the film to be formed is required to have excellent abrasion resistance and adhesion. Furthermore, when forming a film on a substrate other than leather or a plastic film, the film to be formed may also be required to have excellent abrasion resistance. The film forming method of the present disclosure can satisfy such requirements.

[0210] The substrate may be surface-treated in order to improve the surface energy. Examples of surface treatments include, but are not limited to, corona treatment, plasma treatment, flame treatment, heat treatment, abrasion treatment, light irradiation treatment (UV treatment), and flame treatment.

[0211] <Application process> The application step is a step of applying the aqueous dispersion of the present disclosure onto a substrate.

[0212] The method for applying the aqueous dispersion is not particularly limited, and examples thereof include known methods such as a coating method, an ink-jet recording method, and a dipping method.

[0213] The application of the aqueous dispersion by inkjet recording can be carried out by ejecting the aqueous dispersion from an inkjet head of a known inkjet recording device.

[0214] The inkjet head is preferably a piezoelectric type inkjet head. The resolution of the inkjet head is preferably 300 dpi or more, more preferably 600 dpi or more, and even more preferably 800 dpi or more. Here, dpi (dots per inch) represents the number of dots per 2.54 cm (1 inch).

[0215] The droplet volume of the aqueous dispersion ejected from the inkjet head (the appropriate volume per dot) is preferably 1 pL (picoliter) to 100 pL, more preferably 3 pL to 80 pL, and even more preferably 3 pL to 50 pL.

[0216] In the application step, the aqueous dispersion may be applied to a heated substrate. In this case, it is preferable to satisfy at least one of the following: a step of heating the substrate before the application step; and heating the substrate and applying the ink in the application step.

[0217] In this case, the temperature of the surface of the substrate on which the aqueous dispersion lands is preferably 30°C or higher, more preferably 30°C to 100°C, and even more preferably 30°C to 70°C. The heating means for heating the substrate is not particularly limited, and examples thereof include a heat drum, hot air, an infrared lamp, an infrared LED, an infrared heater, a heat oven, a hot plate, an infrared laser, and an infrared dryer.

[0218] <Curing process> The curing step in the film-forming method X is a step of curing the aqueous dispersion applied onto the substrate. This curing step allows a polymerization reaction to proceed due to the particles having polymerizable groups in the aqueous dispersion applied to the substrate, thereby obtaining a film with excellent scratch resistance.

[0219] The curing step is preferably a step of irradiating the aqueous dispersion applied to the substrate with active energy rays.

[0220] Examples of active energy rays include ultraviolet light (UV light), visible light, electron beams, etc. Among these, UV light is preferred as the active energy ray.

[0221] The irradiation of the aqueous dispersion applied to the substrate with active energy rays may be carried out in a state where the substrate and the aqueous dispersion applied to the substrate are heated.

[0222] The irradiation energy of the active energy ray (i.e., the exposure dose) was 20 mJ / cm 2 ~5J / cm 2 and preferably 100 mJ / cm 2 ~1,500mJ / cm 2 It is more preferable that: The irradiation time of the active energy rays is preferably 0.01 seconds to 120 seconds, more preferably 0.1 seconds to 90 seconds. The irradiation conditions and basic irradiation method of the active energy rays can be those disclosed in JP-A-60-132767.

[0223] Examples of light sources for irradiating active energy rays include mercury lamps, metal halide lamps, high-pressure mercury lamps, medium-pressure mercury lamps, low-pressure mercury lamps, ultraviolet fluorescent lamps, gas lasers, solid-state lasers, LEDs (light-emitting diodes), and LDs (laser diodes). Among these, the light source for irradiating active energy rays is preferably a light source for irradiating ultraviolet rays, such as a metal halide lamp, a high-pressure mercury lamp, a medium-pressure mercury lamp, a low-pressure mercury lamp, or an ultraviolet LED (hereinafter also referred to as UV-LED).

[0224] The peak wavelength of the ultraviolet light is, for example, preferably 200 nm to 405 nm, more preferably 220 nm to 400 nm, and even more preferably 340 nm to 400 nm.

[0225] The peak wavelength of the light from the LED light source (LED light) is preferably 200 nm to 600 nm, more preferably 300 nm to 450 nm, even more preferably 320 nm to 420 nm, and even more preferably 340 nm to 400 nm. An example of a UV-LED is a UV-LED manufactured by Nichia Corporation, whose main emission spectrum has a wavelength between 365 nm and 420 nm. Also included are UV-LEDs capable of emitting actinic radiation centered between 300 nm and 370 nm, as described in US Pat. No. 6,084,250. In addition, by combining several UV-LEDs, it is possible to irradiate ultraviolet light in different wavelength ranges.

[0226] A particularly preferred active energy ray is LED light, and particularly preferred is LED light having a peak wavelength in the wavelength range of 340 nm to 405 nm. For example, LED light having a peak wavelength of 355 nm, 365 nm, 385 nm, 395 nm, or 405 nm is more preferred, and LED light having a peak wavelength of 355 nm, 365 nm, 385 nm, 395 nm, or 405 nm is particularly preferred.

[0227] The maximum irradiance of the LED on the substrate is 10mW / cm 2 ~2,000mW / cm 2 is preferred, and 20 mW / cm 2 ~1,000mW / cm 2 is more preferable, and 50 mW / cm 2 ~800mW / cm 2 is more preferable.

[0228]

[0023] As described above, the aqueous dispersion of the present disclosure is preferably an inkjet ink. A preferred embodiment of the present disclosure is an image recording method including the steps of applying the inkjet ink onto a substrate and curing the inkjet ink applied onto the substrate. Details of each step in the image recording method are the same as those of the film forming method. [Example]

[0229] The present disclosure will be specifically described below using examples, but the present disclosure is not limited to the following examples.

[0230] <Resin synthesis> (Polymer PU1) Dimethylolpropionic acid (DMPA) (8.1 g), isophorone diisocyanate (IPDI) (30.4 g), Duranol T5652 (Asahi Kasei Corporation, polycarbonate diol) (21.4 g), bisphenol A epoxy diacrylate (28.8 g), and methyl ethyl ketone (57.1 g) were charged into a three-neck flask and heated to 70° C. 0.1 g of Neostan U-600 (Nitto Kasei Corporation, inorganic bismuth catalyst; hereinafter also referred to as "U-600") was added thereto, and the mixture was stirred at 70° C. for 7 hours. Next, isopropanol (IPA) (62.1 g) as an end-capping agent and ethyl acetate (87.7 g) were added, and the mixture was stirred at 70°C for 3 hours. After stirring for 3 hours, the mixture was allowed to cool to room temperature (25°C; the same applies below). The concentration was adjusted using ethyl acetate, yielding a 30% by mass solution of polymer PU1 (solvent: a mixed solvent of IPA, ethyl acetate, and methyl ethyl ketone). The polymer PU1 had a weight average molecular weight (Mw) of 11000 and an acid value of 0.7 mmol / g. The polymer PU1 has an acryloyl group as a photopolymerizable group.

[0231] (Polymer PU2) Dimethylolpropionic acid (DMPA) (9.6 g), dicyclohexylmethane-4,4-diisocyanate (HMDI) (55.0 g), tricyclodecane dimethanol (14.7 g), bisphenol A epoxy diacrylate (25.9 g), and ethyl acetate (66.1 g) were charged into a three-neck flask and heated to 70° C. U-600 (0.1 g) was added thereto, and the mixture was stirred at 70° C. for 7 hours. Thereafter, a 30% by mass solution of polymer PU2 was obtained in the same manner as for polymer PU1. The weight average molecular weight (Mw) of polymer PU2 was 11000, and the acid value was 0.7 mmol / g. Polymer PU2 has an acryloyl group as a photopolymerizable group.

[0232] (Polymer PU3) Dimethylolpropionic acid (DMPA) (8.0 g), dicyclohexylmethane-4,4-diisocyanate (HMDI) (45.0 g), tricyclodecane dimethanol (16.5 g), bisphenol A epoxy diacrylate (6.8 g), T5652 (11.4 g), and methyl ethyl ketone (48.8 g) were charged into a three-neck flask and heated to 70° C. U-600 (0.1 g) was added thereto, and the mixture was stirred at 70° C. for 7 hours. Thereafter, a 30% by mass solution of polymer PU3 was obtained in the same manner as for polymer PU1. The weight average molecular weight (Mw) of the polymer PU3 was 11000, and the acid value was 0.7 mmol / g. The polymer PU3 has an acryloyl group as a photopolymerizable group.

[0233] (Polymer PU4) Dimethylolpropionic acid (DMPA) (8.5 g), hexamethylene diisocyanate (HDI) (39.4 g), tricyclodecane dimethanol (22.1 g), bisphenol A epoxy diacrylate (23.0 g), and methyl ethyl ketone (60.0 g) were charged into a three-neck flask and heated to 70°C. U-600 (0.1 g) was added thereto, and the mixture was stirred at 70°C for 7 hours. Thereafter, a 30% by mass solution of polymer PU4 was obtained in the same manner as for polymer PU1. The weight average molecular weight (Mw) of the polymer PU4 was 11000, and the acid value was 0.7 mmol / g. The polymer PU4 has an acryloyl group as a photopolymerizable group.

[0234] (Polymer PU5) Dimethylolpropionic acid (DMPA) (10.7 g), isophorone diisocyanate (IPDI) (37.3 g), polyethylene glycol 2000 (Fujifilm Wako Pure Chemical Industries, Ltd.) (40.4 g), bisphenol A epoxy diacrylate (29.0 g), and methyl ethyl ketone (76.3 g) were charged into a three-neck flask and heated to 70°C. U-600 (0.1 g) was added thereto, and the mixture was stirred at 70°C for 7 hours. Thereafter, a 30% by mass solution of polymer PU5 was obtained in the same manner as for polymer PU1. The weight average molecular weight (Mw) of the polymer PU5 was 11000, and the acid value was 0.7 mmol / g. The polymer PU5 has an acryloyl group as a photopolymerizable group.

[0235] (Polymer AC1) Ethyl acetate (101.0 g) and isopropanol (43.3 g) were weighed into a 1000 ml three-neck flask equipped with a condenser and heated and stirred at 65°C under a nitrogen stream. Separately, a mixed solution prepared by mixing ethyl acetate (89.0 g), isopropanol (41.3 g), n-butyl acrylate (5.7 g), methyl methacrylate (107.1 g), methacrylic acid (7.2 g), and 2,2'-azobis(2,4-dimethylvaleronitrile) (V-65, Fujifilm Wako Pure Chemical Industries, Ltd.) (3.7 g) was added dropwise to the above flask over 3 hours. After the addition was completed, the mixture was heated at 65°C for 1 hour, after which V-65 (1.24 g) was added and the mixture was stirred at 70°C for an additional 3 hours. The mixture was then allowed to cool to room temperature. Next, the concentration was adjusted using ethyl acetate to obtain a 30% by mass solution of polymer AC1 (solvent: mixed solvent of IPA and ethyl acetate). The weight average molecular weight (Mw) of polymer AC1 was 11,000, and the acid value was 0.7 mmol / g.

[0236] [Example 1] -Preparation of oil phase components- Ethyl acetate (56.0 g), a 30% by mass solution of polymer PU1 (93.5 g), phenoxyethyl acrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) (12.9 g), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (product name "Omnirad 819", manufactured by IGM Resins BV) (2.4 g), and isopropylthioxanthone (0.4 g) were mixed and stirred for 30 minutes to obtain an oil phase component.

[0237] -Preparation of aqueous phase components- Distilled water (162.4 g) and sodium hydroxide as a neutralizing agent were mixed and stirred for 15 minutes to obtain an aqueous phase component. The amount of sodium hydroxide was adjusted so that the anion value of the particles was 0.33 mmol / g.

[0238] The oil phase component and the aqueous phase component were mixed. The resulting mixture was emulsified at room temperature using a homogenizer at 7000 rpm for 30 minutes to obtain an emulsion. Distilled water (57.6 g) was added to the resulting emulsion, and the resulting liquid was heated to 50°C and stirred at 50°C for 4 hours to obtain a granular emulsion. Ethyl acetate was distilled off from the liquid. The liquid from which ethyl acetate had been distilled off was diluted with distilled water so that the solid content was 25% by mass, thereby obtaining Water Dispersion 1.

[0239] -Ink preparation- The obtained aqueous dispersion 1 was placed in a container, sealed, and left to stand at room temperature for 2 weeks. Using aqueous dispersion 1 after 2 weeks had passed since its preparation, the components were mixed according to the following composition to prepare an ink. The resulting ink is also an embodiment of the aqueous dispersion. ·Aqueous dispersion 1...50% by mass Pigment dispersion (product name "Pro-jet Cyan APD1000", manufactured by FUJIFILM Imaging Colorants), pigment concentration 14% by mass... 15% by mass Fluorosurfactant (product name "Capstone FS-31", manufactured by DuPont, solid content 25% by mass) ... 0.3% by mass Propylene glycol: 15% by mass Water: The remaining amount to make the total ink 100% by mass

[0240] [Examples 2 to 22, Comparative Examples 1 and 2] An aqueous dispersion was prepared in the same manner as in Example 1, except that the types and contents of the resin, photoradical generator, compound having an amino group A, and polymerizable monomer were changed to those shown in Table 1, and an ink was prepared in the same manner as in Example 1. The compound having an amino group A was contained in the oil phase component.

[0241] Details of the photoradical generator, the compound having an amino group A, and the polymerizable monomer are as follows.

[0242] -Photoradical generator (intramolecular cleavage-type photopolymerization initiator)- 819: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (product name "Omnirad 819", molecular weight 418.5 TPO-L: (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide (product name: Omnirad TPO-L, manufactured by IGM Resins BV), molecular weight: 316.3

[0243] -Photoradical generator (intramolecular hydrogen abstraction type photopolymerization initiator)- ITX: Isopropylthioxanthone (product name: "Speedcure ITX", manufactured by Lambson), molecular weight: 254.4 7010: 1,3-di({α-[1-chloro-9-oxo-9H-thioxanthen-4-yl)oxy]acetylpoly[oxy(1-methylethylene)]}oxy)-2,2-bis({α-[1-methylethylene)]}oxymethyl)propane (product name: "Speedcure 7010", manufactured by Lambson), molecular weight: 1200

[0244] -Compound having an amino group A- CN371: Amine-modified acrylate (product name "CN371", manufactured by Sartomer), molecular weight 459.0 N-Gly: N,N-dimethylglycine (Tokyo Chemical Industry Co., Ltd.), molecular weight 103.1 ASA: Poly(ethylene glycol) bis(p-dimethylaminobenzoate) (product name "Omnipol ASA", IGM Resins BV, molecular weight 510.0)

[0245] -Polymerizable monomer- PEA: Phenoxyethyl acrylate (Tokyo Chemical Industry Co., Ltd.), molecular weight 192.2 TCDDMDA: Tricyclodecane dimethanol diacrylate (product name SR833NS, Sartomer Corporation), molecular weight 304.4 GPTA: Glycerin propoxytriacrylate (product name "OTA480", manufactured by Daicel Allnex Co., Ltd.), molecular weight 480.0

[0246] (HSP distance) 500 mg of sample was completely dissolved in 10 mL of tetrahydrofuran (THF), and deionized water was added dropwise to the resulting solution until the solution became cloudy. The volume fraction [deionized water / (deionized water + THF)] at the time the solution became cloudy was defined as Vw.

[0247] 500 mg of sample was completely dissolved in 10 mL of tetrahydrofuran (THF), and hexane was added dropwise to the resulting solution until the solution became cloudy. The volume fraction [hexane / (hexane + THF)] at which the solution became cloudy was defined as Vh.

[0248] The HSP distance between the resin and the photoradical generator, and the HSP distance between the photoradical generator and the compound having an amino group A were calculated using δD, δP, and δH of the resin, photoradical generator, and compound having an amino group A, which were calculated using the above-mentioned formulas.

[0249] When calculating Vh, for Omnirad819, which does not show a cloudy point using the above method, 500 mg of the sample was added to 20 mL of hexane, and THF was added dropwise to estimate the volume fraction based on the amount of THF added just before dissolution. In addition, Vh was set to 1 for Omnirad TPO-L and Speedcure ITX, which are completely soluble in hexane. Dimethylglycine, which is insoluble in THF and hexane but is soluble only in water, was set to the same δD, δP, and δH as water.

[0250] Tables 1 and 2 show δD, δP, and δH calculated by the above-mentioned method for the resin, photoradical generator, and compound having amino group A. When there are two types of photoradical generators, the mass ratio is shown in parentheses.

[0251] [Table 1]

[0252] [Table 2]

[0253] <Membrane formation method> The ink was filled into an ink cartridge attached to an inkjet recording device (product name "DMP-2850", manufactured by Fujifilm Corporation), and the ink was ejected onto a PVC film under conditions of 900 dpi and a droplet volume of 10 pL. After discharging, a 395 nm LED lamp (product name "PEL UV CURE UNIT", manufactured by PRINTED ELECTRONICS) was used to cure the ink at approximately 250 mW / cm 2 The ink film was then exposed to light 10 times at 1000 kJ / cm².

[0254] The prepared ink and the resulting ink film were evaluated for migration, abrasion resistance, ejection properties, and storage stability.

[0255] <Migration> In the above film formation method, ink film A was prepared by applying ink to a substrate, and ink film B was prepared by applying ink to a substrate and then exposing it to light. Each ink film was immersed in a solution of tetrahydrofuran / methanol (mass ratio 1:1). The total amount (extracted amount) of ink components contained in the solution after immersion was measured using HPLC. The amount extracted from ink film A was defined as extraction amount A, and the amount extracted from ink film B was defined as extraction amount B. The extraction rate was calculated based on the following formula. Migration was evaluated based on the extraction rate. The evaluation criteria were as follows: Extraction rate (mass%) = (extraction amount B / extraction amount A) x 100 A: The extraction rate is 1% by mass or less. B: The extraction rate is more than 1% by mass and 3% by mass or less. C: The extraction rate is more than 3% by mass and 5% by mass or less. D: The extraction rate is more than 5% by mass and 10% by mass or less. E: The extraction rate is more than 10% by mass.

[0256] <Abrasion resistance> Using the above-described film formation method, a 3 cm x 10 cm ink film was formed on a substrate at a printing rate of 100%. The substrate on which the ink film was formed was left for 24 hours in an environment of 25°C and 50% relative humidity. After 24 hours, the surface of the ink film was rubbed 100 times with a cotton cloth (Kanakin No. 3) under a load of 200 g using a Gakushin abrasion tester. The surface of the ink film was then visually observed, and the abrasion resistance was evaluated based on the surface condition of the ink film. The evaluation criteria were as follows: A: There were no scratches on the ink film. B: There were slight scratches on the ink film. C: Scratches were found on the ink film, and the substrate was visible over less than 5% of the total area of ​​the ink film. D: Scratches were found on the ink film, and the substrate was visible over 5% or more and less than 50% of the total area of ​​the ink film. E: Almost no ink film remained, and the substrate was visible over 50% or more of the total area of ​​the ink film.

[0257] <Dischargeability> Using the above-described film formation method, the ink was ejected once onto the substrate at a printing rate of 100%. After that, the inkjet recording apparatus was stopped for 30 minutes under conditions of 25°C and a relative humidity of 50%, and the inkjet head was exposed to the atmosphere. After 30 minutes, a nozzle check pattern was selected and ink was ejected once. The recorded nozzle check pattern was visually observed, and the ejection performance was evaluated based on the number of non-ejecting nozzles. The evaluation criteria were as follows: [Evaluation criteria] A: There are no non-ejecting nozzles. B: There are one or two non-ejecting nozzles. C: There are 3 to 4 non-ejecting nozzles. D: There are five or more non-ejecting nozzles. E: Discharge was not possible.

[0258] <Storage stability> After preparation, the ink was stored at room temperature for less than one day, then placed in a container, sealed, and left to stand at 60°C for two weeks. The ink two weeks after preparation (ink four weeks after preparation of the aqueous dispersion) was ejected once onto a substrate at a printing rate of 100% using the film formation method described above. The inkjet recording device was then stopped for 30 minutes under conditions of 25°C and 50% relative humidity, and the inkjet head was exposed to the atmosphere. After 30 minutes, a nozzle check pattern was selected and ink was ejected once. The recorded nozzle check pattern was visually observed, and storage stability was evaluated based on the number of non-ejecting nozzles. The evaluation criteria were as follows: [Evaluation criteria] A: There are no non-ejecting nozzles. B: There are one or two non-ejecting nozzles. C: There are 3 to 4 non-ejecting nozzles. D: There are five or more non-ejecting nozzles. E: Discharge was not possible.

[0259] Table 3 shows the evaluation results.

[0260] The type, C=C value, glass transition temperature (Tg, unit: °C), and content (unit: mass%) of the resin relative to the total amount of the specific particles are listed in Table 3. The C=C value of the resin means the number of millimoles of ethylenic double bonds in 1 g of the resin (unit: mmol / g). For the photoradical generator, the types of intramolecular cleavage-type photopolymerization initiator and intramolecular hydrogen abstraction-type photopolymerization initiator, their ratios to the photoradical generator (unit: mass%), and their content relative to the total amount of specific particles (unit: mass%) are listed. The number-average molecular weight (Mn) of the intramolecular hydrogen abstraction-type photopolymerization initiator is also listed. The "solid ratio" in the photoradical generator column refers to the ratio (unit: mol%) of the moles of photoradical generator present as a solid to the total moles of photoradical generator. The type of compound having an amino group A and the content (unit: mass%) relative to the total amount of the specific particle are shown in Table 3. The "solid ratio" in the column for the compound having an amino group A means the ratio (unit: mol%) of the number of moles of the compound present as a solid to the total number of moles of the compound having an amino group A. Table 3 shows the types of compounds having an amino group A and the content (unit: mass %) relative to the total amount of the specific particles. Table 3 shows the types of polymerizable monomers and their contents (unit: mass %) relative to the total amount of specific particles. In Table 3, "ΔHSP(RP)" means the HSP distance between the resin and the photoradical generator. "ΔHSP(RN)" means the HSP distance between the photoradical generator and the compound having an amino group A. In Table 3, "amino group / photoradical generator" means the ratio (unit: mol %) of the number of moles of amino group A to the total number of moles of the photoradical generator. In Table 3, "photoradical generator in particle" means the number of millimoles of photoradical generator in 1 g of particle (unit: mmol / g). In Table 3, "C=C value of particle" means the number of millimoles of ethylenic double bonds in 1 g of particle (unit: mmol / g). In Table 3, "photoradical generator / C=C" means the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bond (unit: mol %).

[0261] [Table 3]

[0262] As shown in Table 3, Examples 1 to 22 contain water, particles containing a resin and a photoradical generator and having a polymerizable group, the polymerizable group containing an ethylenic double bond, the ratio of the number of moles of photoradical generator to the number of moles of ethylenic double bonds in the particles is 4 mol% or more, and the ratio of the number of moles of photoradical generator present as a solid to the total number of moles of photoradical generator is 5 mol% or less, and therefore it was found that migration was suppressed.

[0263] On the other hand, in Comparative Example 1, the content of the photoradical generator was such that the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles was less than 4 mol %, and therefore migration was observed.

[0264] In Comparative Example 2, the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator in the particles was more than 5 mol%, so migration was observed and the ejection properties and storage stability were poor.

[0265] In Example 4, the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles was 5 mol % or more, and therefore it was found that migration was suppressed compared to Example 3. In Example 6, the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds in the particles was 40 mol % or less, and it was found that the abrasion resistance was superior to that of Example 7.

[0266] In Example 13, the HSP distance between the resin and the photoradical generator was 5.5 MPa. 1 / 2 Since the values ​​are as follows, it was found that the ejection properties and storage stability were superior to those of Example 14.

[0267] In Example 8, the particles further had amino group A having a hydrogen atom on the carbon atom at the α-position, and therefore, it was found that migration was suppressed and abrasion resistance was excellent compared to Example 4.

[0268] In Example 10, the ratio of the number of moles of amino group A having a hydrogen atom on the carbon atom at the α-position to the total number of moles of the photoradical generator was 5 mol% or more, and therefore it was found that migration was suppressed compared to Example 9. In Example 11, the ratio of the number of moles of amino group A having a hydrogen atom on the carbon atom at the α-position to the total number of moles of the photoradical generator was 100 mol% or less, and therefore, compared to Example 12, it was found that migration was suppressed and the ejection properties and storage stability were excellent.

[0269] In Example 9, the ratio of the number of moles of the compound present as a solid to the total number of moles of the compound having an amino group A with a hydrogen atom on the carbon atom at the α-position in the particles was 5 mol% or less, and therefore it was found that the ejection and storage stability were superior compared to Example 17.

[0270] In Example 18, the HSP distance between the photoradical generator and the compound having an amino group A with a hydrogen atom on the α-position carbon atom is 6 MPa. 1 / 2 Since the results are as follows, it was found that migration was suppressed compared to Example 17.

[0271] In Example 15, the glass transition temperature of the resin was 90° C. or lower, and therefore, it was found that migration was suppressed compared to Example 16.

[0272] In Example 6, it was found that migration was suppressed compared to Example 5 because the photoradical generator contained a hydrogen abstraction initiator having a number average molecular weight of 1000 or more.

[0273] In Example 8, the particles contain a polymerizable monomer, and therefore, compared with Example 21, the particles have improved abrasion resistance. I found it to be excellent.

[0274] The disclosure of Japanese Patent Application No. 2021-161314, filed on September 30, 2021, is incorporated herein by reference in its entirety. In addition, all documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. Water and particles containing a resin and a photoradical generator and having a polymerizable group, the polymerizable group contains an ethylenic double bond, In the particles, the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds is 4 mol % or more, and the ratio of the number of moles of the photoradical generator present as a solid to the total number of moles of the photoradical generator under the condition of 25°C is 5 mol% or less, An inkjet ink, a water dispersion.

2. 2. The aqueous dispersion according to claim 1, wherein the ratio of the number of moles of the photoradical generator to the number of moles of the ethylenic double bonds is 5 mol % to 40 mol %.

3. The HSP distance between the resin and the photoradical generator is 5.5 MPa. １／２ The aqueous dispersion according to claim 1 or claim 2, wherein:

4. The aqueous dispersion according to claim 1 or 2, wherein the particles further have an amino group A having a hydrogen atom on the α-position carbon atom.

5. 5. The aqueous dispersion according to claim 4, wherein the ratio of the number of moles of the amino group A having a hydrogen atom on the carbon atom at the α-position to the total number of moles of the photoradical generator is 5 mol % to 100 mol %.

6. The aqueous dispersion according to claim 4 , wherein the particles further contain a compound having an amino group A having a hydrogen atom on the carbon atom at the α-position.

7. The aqueous dispersion according to claim 4 , wherein the particles further contain a compound having an amino group A having a hydrogen atom on the carbon atom at the α-position.

8. The HSP distance between the photoradical generator and the compound having an amino group A having a hydrogen atom on the carbon atom at the α-position is 6 MPa. １／２ The aqueous dispersion according to claim 6, wherein:

9. The aqueous dispersion according to claim 1 or 2, wherein the resin has a glass transition temperature of 90°C or lower.

10. The aqueous dispersion according to claim 1 or 2, wherein the photoradical generator comprises a hydrogen abstraction initiator having a number average molecular weight of 1,000 or more.

11. the particles include a polymerizable monomer; The aqueous dispersion according to claim 1 or 2, wherein the polymerizable group comprises a polymerizable group of the polymerizable monomer.

12. A step of applying the aqueous dispersion according to claim 1 or claim 2 onto a substrate; curing the aqueous dispersion applied to the substrate; A film forming method comprising the steps of:

Images