Dental composition

Abstract

Provided is a dental composition from which there can be obtained a cured product having a large photocurable depth, high mechanical strength, low polymerization shrinkage stress, and high surface hardness. The dental composition comprises a monomer (A), a polymerization initiator (B), and a filler (C). The monomer (A) comprises a monomer (A-1) represented by formula (1) and a monomer (A-2) which is other than the monomer (A-1). The filler (C) is included at 50-90 mass% in 100 mass% of the dental composition. [The symbols in formula (1) are as defined in the description of the present application.]

Description

Dental Composition

[0001] The present invention relates to a dental composition.

[0002] Known dental compositions include dental filling and restorative materials, such as dental composite resins, self-adhesive dental composite resins, and dental cements, which are used to fill or repair cavities formed in teeth, as well as dental core buildup materials, which are used to plug or cover large missing non-vital teeth and restore them to the shape of an abutment tooth. Conventionally, dental compositions containing polymerizable monomers having a bisphenol A skeleton, such as 2,2-bis[4-(meth)acryloyloxypolyethoxyphenyl]propane, have been widely used to ensure that the cured products of these dental compositions have sufficient strength. It is also known to add fillers to dental compositions for purposes such as adjusting paste properties, imparting X-ray contrast to the cured products, and improving the mechanical strength of the cured products.

[0003] However, conventional polymerizable monomers having a bisphenol A skeleton do not have a sufficiently high refractive index, and therefore, dental compositions containing conventional polymerizable monomers having a bisphenol A skeleton have a large refractive index difference from the filler, which tends to cause light scattering and therefore tends to have a small photocuring depth. A small photocuring depth makes it difficult to sufficiently cure the dental composition, resulting in problems such as difficulty in improving the mechanical strength of the cured product. Therefore, there is a demand for dental compositions that have a larger photocuring depth and can produce cured products with high mechanical strength.

[0004] Meanwhile, dental materials containing polymerizable monomers that do not contain a bisphenol A skeleton have also been proposed (see, for example, Patent Documents 1 to 8). Patent Document 9, while not related to dental filling and restorative materials or dental core construction materials, describes a stereolithography resin composition for use in dental occlusal splints and the like, which contains an α,β-unsaturated double bond group-containing compound having a nitrogen-containing cyclic structure (a), a (meth)acrylic acid ester compound having a predetermined boiling point at atmospheric pressure, a carbocyclic group, and no nitrogen-containing heterocyclic group, and a photopolymerization initiator. However, the invention described in Patent Document 9 addresses technical issues such as odor, moldability, toughness, and water resistance, and does not consider light scattering when a filler is contained in the resin composition. Patent Document 9 does not describe or suggest how to ensure a sufficiently large photocuring depth while containing a high proportion of filler in the resin composition.

[0005] Japanese Patent Publication No. 2013-60373, Japanese Patent No. 5008852, International Publication No. 2019 / 107322, Japanese Patent No. 5819415, Japanese Patent Publication No. 2010-506931, Japanese Patent No. 6458034, International Publication No. 2020 / 218446, International Publication No. 2021 / 132463, International Publication No. 2020 / 129736

[0006] However, conventional dental compositions still have room for improvement, and it is difficult to obtain a cured product that has a large photocuring depth and is good in all aspects of mechanical strength, polymerization shrinkage stress, and surface hardness. Therefore, there is still a need for novel and useful dental compositions that differ from conventional ones. Therefore, an object of the present invention is to provide a dental composition that can provide a cured product that has high mechanical strength, low polymerization shrinkage, a large photocuring depth, and high surface hardness.

[0007] As a result of extensive investigations, the present inventors have found that the above-mentioned problems can be solved by preparing a dental composition containing a monomer having a specific structure and a predetermined amount of filler, and have arrived at the present invention. That is, the present invention encompasses the following inventions.

[0008] [1] A dental composition comprising a monomer (A), a polymerization initiator (B), and a filler (C), wherein the monomer (A) comprises a monomer (A-1) represented by the following formula (1) and a monomer (A-2) other than the monomer (A-1), and the dental composition contains 50 to 90% by mass of the filler (C) relative to 100% by mass of the total of the dental composition: [In the above formula (1), R １ represents a hydrogen atom or a methyl group, and R ２ represents a divalent hydrocarbon group, and R ３ represents an oxygen atom or a sulfur atom. ４ and R ５ are each independently a halogen atom, an alkyl group, or an alkoxy group. m is 0 or 1, n is 0 or 1, p is 0 to 3, and q is 0 to 4. However, when m is 0, n is 0. When p is 2 or more, multiple R ４ are the same atom or group, or are different atoms or groups. When q is 2 or more, there are multiple R ５ are the same atom or group, or are different atoms or groups.] [2] The dental composition according to the above item [1], which contains 1 to 80 parts by mass of the monomer (A-1) based on 100 parts by mass of the total mass of the monomer (A-1) and the monomer (A-2). [3] The dental composition according to the above item [1] or [2], wherein the monomer (A-1) is a monomer (A-1a) represented by the following formula (2): [In the above formula (2), R １ , R ２ , R ３, m, and n are as defined in formula (1).] [4] The dental composition according to any one of the above [1] to [3], wherein the monomer (A-1) is 1-naphthylmethyl (meth)acrylate. [5] The dental composition according to any one of the above [1] to [4], wherein the monomer (A-2) includes a monomer having a urethane bond. [6] The dental composition according to any one of the above [1] to [5], wherein the monomer (A-2) includes a monomer having a (meth)acryloyl group. [7] The dental composition according to any one of the above [1] to [6], wherein the content of a monomer having a bisphenol A skeleton is more than 0% by mass and not more than 30% by mass, or wherein the dental composition does not include a monomer having a bisphenol A skeleton. [8] The dental composition according to any one of the above [1] to [7], wherein the dental composition is a dental composite resin. [9] The dental composition according to any one of [1] to [7] above, wherein the dental composition is a dental cement.

[10] The dental composition according to any one of [1] to [7] above, wherein the dental composition is a self-adhesive dental composite resin.

[11] The dental composition according to any one of [1] to [7] above, wherein the dental composition is a dental core build-up material.

[0009] The present invention provides a dental composition that can give a cured product having a large photocuring depth, high mechanical strength, low polymerization shrinkage stress, and high surface hardness.

[0010] The present invention will be described in detail below using embodiments. In this specification, the upper and lower limits of numerical ranges (such as the content of each component, values ​​calculated from each component, and physical properties) can be combined as appropriate. Furthermore, in this specification, the numerical values ​​of each symbol in a formula can also be combined as appropriate. That is, in this specification, the lower and upper limits described in stages for a numerical range can be independently combined. For example, a description of the same item, "preferably 10 to 90, more preferably 30 to 60," can be combined with a "preferable lower limit (10)" and a "more preferable upper limit (60)" to form "10 to 60." Furthermore, for a numerical range, for example, based on a description of "preferably 10 to 90, more preferably 30 to 60," the upper limit can be specified as "10 or more" or "30 or more" without specifying a specific upper limit. Similarly, the upper limit can be specified as "90 or less" or "60 or less" without specifying a specific lower limit. Unless otherwise specified, when a numerical range is simply stated as "10 to 90," it represents a range of 10 or more and 90 or less. As above, for example, from the description of "preferably 10 or more, more preferably 30 or more" and the description of "preferably 90 or less, more preferably 60 or less" for the same item, the "preferable lower limit (10)" and the "more preferable upper limit (60)" can be combined to form "10 or more and 60 or less." Furthermore, as above, only the lower limit can be specified as "10 or more" or "30 or more," and similarly, only the lower limit can be specified as "90 or less" or "60 or less."

[0011] In this specification, the term "(meth)acrylic" is used to encompass both "methacrylic" and "acrylic." The same applies to similar terms such as "(meth)acrylate," "(meth)acrylic acid ester," "(meth)acrylamide," and "(meth)acryloyloxy." In this specification, the term "(meth)acrylic monomer" or "(meth)acrylic compound" is used to encompass both "(meth)acrylic acid ester compound" and "(meth)acrylamide and its derivatives."

[0012] [Dental Composition] A dental composition according to an embodiment of the present invention is a dental composition comprising a monomer (A), a polymerization initiator (B), and a filler (C), wherein the monomer (A) comprises a monomer (A-1) represented by the following formula (1) and a monomer (A-2) other than the monomer (A-1), and the dental composition contains 50 to 90% by mass of the filler (C) relative to 100% by mass of the total dental composition:

[0013] The dental composition has a high photocuring depth and its cured product has high mechanical strength, low polymerization shrinkage stress, and high surface hardness. The following factors are presumed to be contributing factors, but are not limited to these. First, the structure of the compound represented by formula (1) (hereinafter also referred to as "compound (1)") has a relatively rigid skeleton. This, combined with the presence of a high proportion of filler, is thought to contribute to the high mechanical strength and high surface curing properties of the cured dental composition. Furthermore, because compound (1) is monofunctional, it is presumed that polymerization shrinkage stress is reduced when the dental composition is cured. Furthermore, compound (1) has a naphthalene skeleton with two linked aromatic rings, which generally gives it a high refractive index, thereby reducing the refractive index difference between the monomer component and the filler. This is thought to reduce scattering due to the refractive index difference between the monomer component and the filler, ultimately resulting in a dental composition with a high photocuring depth. The meanings of each symbol in formula (1) will be described later.

[0014] <Monomer (A)> The monomer (A) includes a monomer (A-1) represented by the above formula (1) and a monomer (A-2) other than the monomer (A-1). Hereinafter, the monomer (A-1) represented by the above formula (1) may be simply referred to as "monomer (A-1)," and the monomer (A-2) other than the monomer (A-1) may be simply referred to as "monomer (A-2)."

[0015] (Monomer (A-1)) The monomer (A-1) is at least one compound represented by the above formula (1). The monomer (A-1) may be a single compound represented by the above formula (1), or may be a mixture of multiple types of compounds represented by the above formula (1).

[0016] In the above formula (1), R １ represents a hydrogen atom or a methyl group, and is preferably a methyl group.

[0017] In the above formula (1), R ２ represents a divalent hydrocarbon group, preferably a methylene group.

[0018] In the above formula (1), R ３ represents an oxygen atom or a sulfur atom, and is preferably an oxygen atom.

[0019] In the above formula (1), R ４ and R ５ each independently represents a halogen atom, an alkyl group, or an alkoxy group, and is preferably a halogen atom or an alkyl group.

[0020] In the above formula (1), m represents 0 or 1, and n represents 0 or 1. However, when m is 0, n represents 0. When m is 1 and n is 0, R ２ One bond of the oxygen atom bonded to the carbonyl group in formula (1) is bonded to a carbon atom on the naphthalene skeleton in formula (1). When m and n are 0, the other bond of the oxygen atom bonded to the carbonyl group in formula (1) is bonded to a carbon atom on the naphthalene skeleton in formula (1). In the above formula (1), it is preferable that m is 1 and n is 0.

[0021] In the above formula (1), p represents 0 to 3, and q represents 0 to 4. When p is 2 or more, a plurality of R ４ are the same atom or group, or are different atoms or groups. When q is 2 or more, a plurality of R ５ are the same atom or group, or are different atoms or groups. In the above formula (1), it is preferable that p is 0 and q is 0.

[0022] From the viewpoint of facilitating an increase in mechanical strength and surface hardness, the monomer (A-1) is preferably a monomer (A-1a) represented by the following formula (2):

[0023] In the above formula (2), R １ , R ２ , R ３, m, and n have the same meanings as defined in the above formula (1), and the preferred values ​​are also the same as those described above.

[0024] From the viewpoint of preventing a decrease in the photocuring depth and further reducing the polymerization shrinkage stress, the monomer (A-1) is more preferably a monomer (A-1b) represented by the following formula (3):

[0025] In the above formula (3), R １ , R ２ , R ３ , m, and n are defined as in formula (1) above.

[0026] From the viewpoint of preventing a decrease in the photocuring depth and further facilitating a reduction in the polymerization shrinkage stress, the monomer (A-1) is more preferably a monomer (A-1c) represented by the following formula (4):

[0027] In the above formula (4), R １ , R ２ , and m are defined as in the above formula (1).

[0028] The monomer (A-1) is more preferably 1-naphthylmethyl(meth)acrylate or 2-naphthylmethyl(meth)acrylate from the viewpoint of easily increasing the mechanical strength and surface hardness, and is even more preferably 1-naphthylmethyl(meth)acrylate, and particularly preferably 1-naphthylmethyl methacrylate from the viewpoint of easily reducing the polymerization shrinkage stress while preventing a decrease in the photocuring depth.

[0029] (Monomer (A-2)) Monomer (A-2) is a compound different from monomer (A-1), that is, a polymerizable monomer having a structure different from compound (1). From the viewpoint of the mechanical strength of the cured product, monomer (A-2) preferably contains a monomer having a urethane bond, and more preferably a polyfunctional polymerizable monomer containing a urethane bond. Furthermore, from the viewpoint of curability, monomer (A-2) preferably contains a monomer having a (meth)acryloyl group, and from the viewpoint of further enhancing curability, it is more preferable to contain a monomer having a plurality of (meth)acryloyl groups.

[0030] The monomer (A-2) will be described in detail below. Examples of the monomer (A-2) include a monofunctional polymerizable monomer having one polymerizable group and a polyfunctional polymerizable monomer having multiple polymerizable groups. From the viewpoint of obtaining good curability, it is preferable that the monomer (A-2) contains a polyfunctional polymerizable monomer.

[0031] Examples of the monofunctional polymerizable monomer include a monofunctional (meth)acrylate polymerizable monomer and a monofunctional (meth)acrylamide polymerizable monomer.

[0032] Examples of the monofunctional (meth)acrylate polymerizable monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, propylene glycol mono(meth)acrylate, glycerol mono(meth)acrylate, erythritol mono(meth)acrylate, methyl (meth)acrylate, and ethyl (meth)acrylate. acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate ester, o-phenylphenol (meth)acrylate, m-phenylphenol (meth)acrylate, p-phenylphenol (meth)acrylate, pentabromobenzyl (meth)acrylate, pentachlorophenyl (meth)acrylate, anthracenyl (meth)acrylate, anthracenemethyl (meth)acrylate, o-phenylphenoxymethyl (meth)acrylate, m-phenylphenoxymethyl (meth)acrylate, p-phenylphenoxymethyl (meth)acrylate, o-phenylphenoxyethyl (meth)acrylate , m-phenylphenoxyethyl (meth)acrylate, p-phenylphenoxyethyl (meth)acrylate, o-phenylphenoxypropyl (meth)acrylate, m-phenylphenoxypropyl (meth)acrylate, p-phenylphenoxypropyl (meth)acrylate, o-phenylphenoxybutyl (meth)acrylate, m-phenylphenoxybutyl (meth)acrylate, p-phenylphenoxybutyl (meth)acrylate, o-phenoxybenzyl (meth)acrylate, m-phenoxybenzyl (meth)acrylate,p-phenoxybenzyl (meth)acrylate, 2-(o-phenoxyphenyl)ethyl (meth)acrylate, 2-(m-phenoxyphenyl)ethyl (meth)acrylate, 2-(p-phenoxyphenyl)ethyl (meth)acrylate, 3-(o-phenoxyphenyl)propyl (meth)acrylate, 3-(m-phenoxyphenyl)propyl (meth)acrylate, 3-(p-phenoxyphenyl)propyl (meth)acrylate, 4-(o-phenoxyphenyl)butyl (meth)acrylate, 4-(m-phenoxyphenyl)butyl (meth)acrylate, 4-(p-phenoxyphenyl)butyl (meth)acrylate, 5-(o-phenoxyphenyl)pentyl (meth)acrylate, 5-(m-phenoxyphenyl)pentyl ( Examples of the acrylate include 5-(p-phenoxyphenyl)pentyl (meth)acrylate, 6-(o-phenoxyphenyl)hexyl (meth)acrylate, 6-(m-phenoxyphenyl)hexyl (meth)acrylate, 6-(p-phenoxyphenyl)hexyl (meth)acrylate, piperidinyl (meth)acrylate, tetramethylpiperidinyl (meth)acrylate, pentamethylpiperidinyl (meth)acrylate, (meth)acrylic acid, potassium (meth)acrylate, magnesium (meth)acrylate, zinc (meth)acrylate, 2,3-dibromopropyl (meth)acrylate, 3-(meth)acryloyloxypropyltrimethoxysilane, and 11-(meth)acryloyloxyundecyltrimethoxysilane. These may be used alone or in combination of two or more.

[0033] Examples of the monofunctional (meth)acrylamide polymerizable monomer include (meth)acrylamide, N-(meth)acryloylmorpholine, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-di-n-propyl(meth)acrylamide, N,N-di-n-butyl(meth)acrylamide, N,N-di-n-hexyl(meth)acrylamide, N,N-di-n-octyl(meth)acrylamide, and N,N-di-2-ethylhexyl(meth)acrylamide. amide, N-hydroxyethyl(meth)acrylamide, N,N-bis(2-hydroxyethyl)acrylamide, N-(meth)acryloylcarbazole, N-methyl-N-phenyl(meth)acrylamide, N-(meth)acryloylmorpholine, N-piperidinyl acrylamide, N-tetramethylpiperidinyl acrylamide, N-2-methylpiperidinyl acrylamide, N-3-methylpiperidinyl acrylamide, and N-4-methylpiperidinyl acrylamide. These may be used alone or in combination of two or more.

[0034] The structure of the polyfunctional polymerizable monomer is not particularly limited, but a polyfunctional polymerizable monomer containing a urethane bond is preferred in terms of excellent curability. In addition, examples of the polyfunctional polymerizable monomer include an aromatic compound-based polyfunctional polymerizable monomer and an aliphatic compound-based polyfunctional polymerizable monomer, but an aromatic compound-based polyfunctional polymerizable monomer is preferred in terms of easily obtaining good curability.

[0035] The polyfunctional polymerizable monomer containing a urethane bond may be any compound in which a urethane bond is introduced adjacent to a (meth)acrylate group, and examples thereof include urethane-modified (meth)acrylate polymerizable monomers having at least one structure selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene in one molecule (hereinafter, these may be referred to as "polymer skeleton"), and urethane-modified (meth)acrylate polymerizable monomers having no polymer skeleton. Among these, urethane-modified (meth)acrylate polymerizable monomers having a polymer skeleton are preferred in terms of excellent flexibility, and those having an aromatic ring in the repeating unit constituting the polymer skeleton are more preferred.

[0036] A urethane-modified (meth)acrylate-based polyfunctional polymerizable monomer having a polymer skeleton can be easily synthesized, for example, by subjecting a polyol containing the polymer skeleton, a compound having an isocyanate group (—NCO), and a (meth)acrylate compound having a hydroxyl group (—OH). Alternatively, a urethane-modified (meth)acrylate-based polyfunctional polymerizable monomer having a polymer skeleton can be easily synthesized by subjecting a (meth)acrylate compound having a hydroxyl group to a ring-opening addition reaction with a lactone or an alkylene oxide, and then subjecting the resulting compound having a hydroxyl group at one end to an addition reaction with a compound having an isocyanate group.

[0037] The polyol containing the polymer skeleton is not particularly limited as long as it has the above structure. For example, polyesters include polymers of phthalic acid and alkylene diols having 2 to 12 carbon atoms, polymers of adipic acid and alkylene glycols having 2 to 12 carbon atoms, polymers of maleic acid and alkylene diols having 2 to 12 carbon atoms, polymers of β-propiolactone, polymers of γ-butyrolactone, polymers of δ-valerolactone, polymers of ε-caprolactone, and copolymers thereof. Examples of polycarbonates include polycarbonates derived from aliphatic diols having 2 to 12 carbon atoms, polycarbonates derived from bisphenol A, and polycarbonates derived from aliphatic diols having 2 to 12 carbon atoms and bisphenol A. Examples of polyurethanes include polymers of aliphatic diols having 2 to 12 carbon atoms and diisocyanates having 1 to 12 carbon atoms. Examples of polyethers include polyethylene glycol, polypropylene glycol, polybutylene glycol, and poly(1-methylbutylene glycol). The polyconjugated dienes and hydrogenated polyconjugated dienes include 1,4-polybutadiene, 1,2-polybutadiene, polyisoprene, poly(butadiene-isoprene), poly(butadiene-styrene), poly(isoprene-styrene), polyfarnesene, and hydrogenated versions thereof.

[0038] Examples of compounds having an isocyanate group include hexamethylene diisocyanate (HDI), tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), trimethylhexamethylene diisocyanate (TMHMDI), tricyclodecane diisocyanate (TCDDI), and adamantane diisocyanate (ADI).

[0039] Examples of the (meth)acrylate compound having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycerin mono(meth)acrylate, and N-hydroxyethyl (meth)acrylamide. hydroxy(meth)acrylate compounds such as dipentaerythritol tri(meth)acrylate, N,N-bis(2-hydroxyethyl)(meth)acrylamide, 2-hydroxy-3-acryloyloxypropyl(meth)acrylate, 2,2-bis[4-[3-(meth)acryloyloxy-2-hydroxypropoxy]phenyl]propane, 1,2-bis[3-(meth)acryloyloxy-2-hydroxypropoxy]ethane, pentaerythritol tri(meth)acrylate, and dipentaerythritol tri- or tetra(meth)acrylate.

[0040] The addition reaction between a compound having an isocyanate group and a (meth)acrylate compound having a hydroxyl group can be carried out according to a known method, and is not particularly limited.

[0041] Examples of the urethane-modified (meth)acrylate-based polyfunctional polymerizable monomer having a polymer skeleton obtained by the above-mentioned method include reaction products of any combination of the above-mentioned polyol having at least one structure selected from the group consisting of polyester, polycarbonate, polyurethane, polyether, polyconjugated diene, and hydrogenated polyconjugated diene, a compound having an isocyanate group, and a (meth)acrylate compound having a hydroxyl group. Commercially available products can also be used as the urethane-modified (meth)acrylate-based polyfunctional polymerizable monomer having a polymer skeleton. Examples of commercially available products include "UFC-01" (manufactured by Kyoeisha Chemical Co., Ltd.) and "EBECRYL8465" (manufactured by Daicel-Allnex Corporation), which are urethane acrylates.

[0042] The weight average molecular weight (Mw) of the urethane-type (meth)acrylate polyfunctional polymerizable monomer having a polymer skeleton is, from the viewpoints of viscosity and strength, preferably from 500 to 50,000, more preferably from 750 to 30,000, and even more preferably from 1,000 to 15,000. Note that the weight average molecular weight (Mw) in the present invention means the weight average molecular weight in terms of polystyrene determined by gel permeation chromatography (GPC).

[0043] Examples of urethanized (meth)acrylate polyfunctional polymerizable monomers that do not have a polymer skeleton include 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (commonly known as "UDMA"), N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetra(meth)acrylate, phenyl glycidyl ether acrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, pentaerythritol triacrylate isophorone diisocyanate urethane prepolymer, and dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer.

[0044] Examples of aromatic compound-based polyfunctional polymerizable monomers include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(3-acryloyloxy)-2-hydroxypropoxyphenyl]propane, 2,2-bis[4-(3-methacryloyloxy)-2-hydroxypropoxyphenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane. phenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl) ) propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (one having an average number of moles of ethoxy groups added of 2.6, commonly known as "D-2.6E"), and 1,4-bis(2-(meth)acryloyloxyethyl)pyromellitate. These may be used alone or in combination of two or more.

[0045] However, from the viewpoint of easily preventing a decrease in the photocuring depth, the dental composition preferably contains more than 0% by mass and not more than 30% by mass of a monomer having a bisphenol A skeleton, or does not contain a monomer having a bisphenol A skeleton. When the dental composition contains a monomer having a bisphenol A skeleton, the content is more preferably more than 0% by mass and not more than 25% by mass, and even more preferably more than 0% by mass and not more than 20% by mass.

[0046] Therefore, among the above-mentioned monomers, it is preferable that the content of monomers containing a bisphenol A skeleton (i.e., compounds excluding 1,4-bis(2-(meth)acryloyloxyethyl)pyromellitate from the compounds exemplified as aromatic compound-based polyfunctional polymerizable monomers) is more than 0 mass % and 30 mass % or less relative to the total mass of the dental composition, or that they are not contained in the dental composition.

[0047] Examples of the aliphatic compound-based polyfunctional polymerizable monomers include bifunctional polymerizable monomers such as glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, pentaethylene glycol di(meth)acrylate, hexaethylene glycol di(meth)acrylate, heptaethylene glycol di(meth)acrylate, octaethylene glycol di(meth)acrylate, nonaethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, pentapropylene glycol di(meth)acrylate, di(meth)acrylate, hexapropylene glycol di(meth)acrylate, heptapropylene glycol di(meth)acrylate, octapropylene glycol di(meth)acrylate, nonapropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 2-ethyl-1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, and tricyclodecane dimethanol di(meth)acrylate.Furthermore, examples of the aliphatic compound-based polyfunctional polymerizable monomer include tri- or higher functional polymerizable monomers, such as trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane. These may be used alone or in combination of two or more.

[0048] When the monomer (A-2) contains at least one of a urethane-type (meth)acrylate-based polyfunctional polymerizable monomer, an aliphatic compound-based polyfunctional (meth)acrylate-based polymerizable monomer, and an aromatic compound-based polyfunctional (meth)acrylate-based polymerizable monomer, the content of the polyfunctional (meth)acrylate-based polymerizable monomer in 100 parts by mass of the total amount of the monomer (A-2) is preferably 20 to 90 parts by mass, more preferably 30 to 80 parts by mass, and even more preferably 40 to 70 parts by mass. When the monomer (A-2) contains a monofunctional (meth)acrylate polymerizable monomer or a monofunctional (meth)acrylamide polymerizable monomer, the content of the monofunctional (meth)acrylate polymerizable monomer or the monofunctional (meth)acrylamide polymerizable monomer is preferably 0 to 60 parts by mass, more preferably 5 to 55 parts by mass, and even more preferably 10 to 50 parts by mass, per 100 parts by mass of the total amount of the monomer (A-2).

[0049] It is preferable that the monomer (A-2) does not contain an α,β-unsaturated double bond group-containing compound having a cyclic structure containing a nitrogen atom, or that the content of such a compound is more than 0% by mass and 10% by mass or less. Examples of the α,β-unsaturated double bond group-containing compound having a cyclic structure containing a nitrogen atom include compounds having a cyclic structure containing one or more nitrogen atoms as heteroatoms within the structure and containing an α,β-unsaturated double bond group. Examples of the cyclic structure containing one or more nitrogen atoms include a cyclic structure containing only one or more nitrogen atoms as heteroatoms on the cyclic structure, a cyclic structure containing both nitrogen and oxygen atoms as heteroatoms on the cyclic structure, and a cyclic structure containing both nitrogen and sulfur atoms as heteroatoms on the cyclic structure. Examples of the α,β-unsaturated double bond group include a (meth)acryloyl group, a vinyl group, an N-vinyl group, a vinyl ester group, a vinylsilyl group, a vinyl ether group, an allyl group, and a methallyl group.

[0050] Examples of the α,β-unsaturated double bond group-containing compound containing only one nitrogen atom as a heteroatom on the cyclic structure include pentamethylpiperidinyl(meth)acrylate (also known as 1,2,2,6,6-pentamethyl-4-piperidyl(meth)acrylate), tetramethylpiperidinyl(meth)acrylate (also known as 2,2,6,6-tetramethyl-4-piperidyl(meth)acrylate), piperidinyl(meth)acrylate (also known as 4-piperidyl(meth)acrylate), 4-(pyrimidin-2-yl)piperazin-1-yl(meth)acrylate, (meth)acrylic acid esters having a nitrogen atom-containing monocyclic ring structure such as N-(meth)acryloylpyrrolidine, N-(meth)acryloylpiperidine, piperidyl(meth)acrylamide (also known as N-(piperidin-4-yl)(meth)acrylamide), N-(meth)acryloyl-2-methylpiperidine, N-(meth)acryloyl-2,2,6,6-tetramethylpiperidine, etc.; (meth)acrylamides having a nitrogen atom-containing monocyclic ring structure such as 1-vinylpyrrole, 2-vinylpyrrole, 2-methyl-5-vinyl-1H-pyrrole, 1-vinyl vinyl group-containing compounds having a five-membered ring containing a nitrogen atom, such as 1-vinyl-2-imidazoline, 2-vinyl-2-imidazoline, 1-vinyl-2-methyl-2-imidazoline, 4,5-dihydro-2-vinyl-1H-imidazole, 1-vinylimidazole, 2-vinyl-1H-imidazole, 1-vinyl-1H-pyrazole, 1-vinyl-3,5-dimethyl-1H-pyrazole, and 3-methyl-5-phenyl-1-vinylpyrazole; 2-vinylpiperazine, 4-vinylpiperazine, 1-benzyl-2-vinylpiperazine, and 1-benzyl-3-vinylpiperazine; vinyl group-containing compounds having a six-membered ring containing a nitrogen atom, such as 1,4-dimethyl-3-vinylpiperazine, 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 6-methyl-2-vinylpyridine, 2-vinylpyrazine, 2-methyl-5-vinylpyrazine, 2-methyl-6-vinylpyrazine, 2,5-dimethyl-3-vinylpyrazine, 2-vinylpyrimidine, 2-vinylpyridazine, 2-vinyl-4,6-diamino-1,3,5-triazine, 6-vinyl-1,3,5-dimethyl-2,4-diamine, and 3-vinyl-1,2,4,5-tetrazine;vinyl group-containing compounds having an acyl group and a nitrogen atom-containing six-membered ring, such as vinyl nicotinoyl acetate, vinyl nicotinoyl propionate, vinyl nicotinoyl butyrate, vinyl nicotinoyl valerate, vinyl nicotinoyl hexanoate, vinyl nicotinoyl decanoate, vinyl nicotinoyl dodecanoate, vinyl isonicotinoyl acetate, vinyl isonicotinoyl propionate, vinyl isonicotinoyl butyrate, vinyl isonicotinoyl valerate, vinyl isonicotinoyl hexanoate, vinyl isonicotinoyl decanoate, and vinyl isonicotinoyl dodecanoate; 1-vinyl indole, 1-vinyl-2-methyl-1H-indole, 1-vinylisoindole, 1-vinyl-1H-benzimidazole, 2-vinyl-1 vinyl group-containing compounds having a nitrogen atom-containing polycyclic structure such as 1H-benzimidazole, 2-vinyl-5,6-dimethyl-1H-benzimidazole, 1-vinylindazole, 2-vinylquinoline, 4-vinylquinoline, 2-vinylisoquinoline, 2-vinylisoxaline, 2-vinylquinoxaline, 2-vinylquinazoline, 2-vinylcinnoline, 1-vinylcarbazole, and N-vinylcarbazole; nitrogen atom-containing monocyclic structure and two or more vinyl group-containing compounds such as 1-methyl-4,5-divinyl-1H-imidazole, 1,1'-divinyl-2,2'-bi(1H-imidazole), 2,3-divinylpyridine, 2,4-divinylpyridine, 2,5-divinylpyridine, and 2,6-divinylpyridine;1-(meth)allyl-1H-imidazole (1-allyl-1H-imidazole and 1-methallyl-1H-imidazole are collectively referred to as "1-(meth)allyl-1H-imidazole". The same applies hereinafter). ), 1-(meth)allyl-2-methyl-1H-imidazole, 1-(meth)allyl-3-methyl-1H-imidazol-3-ium, 1-(meth)allyl-3-ethyl-1H-imidazol-3-ium, 4-(meth)allyl-3,5-dimethyl-1H-pyrazole, 5-bromo-1-1-(meth)allyl-1H-pyrazole, 1-(meth)allylpiperazine, 5-(1-methylpropyl)-5-(meth)allylpyrimidine, 5-(meth)allyl-5-isopropylpyrimidine, 1-(meth)allyl-5,5-diethylpyrimidine, 2-(meth)allylpyridine, 4-(meth)allylpyridine, 3,6-dihydro-3-(meth)allylpyridine, and the like nitrogen atoms. (meth)allyl group-containing compounds having a cyclic structure containing an allyl group; (meth)allyl group-containing compounds having a polycyclic structure containing a nitrogen atom, such as 2-(meth)allyl-1H-indole, 3-(meth)allyl-1H-indole, 1-(meth)allyl-1H-benzimidazole, 2-(meth)allylindazole, 1-(meth)allyl-3-methyl-1H-indazole, 1-(meth)allyl-4-methyl-1H-indazole, N-(meth)allylquinolin-4-amine, di(meth)allylquinoline, 3-phenyl-4-(meth)allylisoquinoline, 1,2-di(meth)allyl-1,2-dihydroisoquinoline, and 9-(meth)allyl-9H-carbazole;

[0051] Examples of the α,β-unsaturated double bond group-containing compound containing two or more nitrogen atoms as heteroatoms on the cyclic structure include 2-(2'-hydroxy-5'-(meth)acryloyloxyethylphenyl)-2H-benzotriazole, 2-(2'-hydroxy-5'-(meth)acryloyloxyethylphenyl)-5-chloro-2H-benzotriazole, 2-(2'-hydroxy-5'-(meth)acryloyloxypropylphenyl)-2H-benzotriazole, 2-(2'-hydroxy-5'-(meth)acryloyloxypropylphenyl)-2H-benzotriazole, 2-(2'-hydroxy-5'-(meth)acryloyloxypropylphenyl)-2H-benzotriazole, (meth)acrylic acid esters having a nitrogen atom-containing polycyclic structure, such as 2-(2'-hydroxy-3'-tert-butyl-5'-(meth)acryloyloxyethylphenyl)-5-chloro-2H-benzotriazole, 2-(2'-hydroxy-3'-tert-butyl-5'-(meth)acryloyloxyethylphenyl)-5-chloro-2H-benzotriazole; 2,4-diphenyl-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazole; 2,4-bis(2-methylphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, 2,4-bis(2-methoxyphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, 2,4-bis(2-ethylphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, 2,4-bis(2-ethoxyphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy} ]-S-triazine, 2,4-bis(2,4-dimethylphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, 2,4-bis(2,4-diethoxylphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, 2,4-bis(2,4-diethylphenyl)-6-[2-hydroxy-4-{2-(meth)acryloyloxyethoxy}]-S-triazine, and other (meth)acrylic acid esters having a six-membered ring containing a nitrogen atom.

[0052] Examples of the α,β-unsaturated double bond group-containing compound containing both a nitrogen atom and an oxygen atom as hetero atoms on the cyclic structure include (meth)acrylic acid esters having a cyclic structure containing an oxygen atom in addition to a nitrogen atom, such as imido(meth)acrylate, 2-(4-oxazolin-3-yl)ethyl(meth)acrylate, tri(meth)acrylic acid ethoxylated isocyanuric acid, and ε-caprolactone-modified tris-(2-acryloyloxyethyl)isocyanurate; (meth)acrylamides having a cyclic structure such as 4-acryloylmorpholine; N-vinyl group-containing compounds having a cyclic structure containing both a nitrogen atom and an oxygen atom, such as N-vinyl-2-pyrrolidone and N-vinyl-ε-caprolactam; maleimide, methylmaleimide, ethylmaleimide, maleimide derivatives having both a nitrogen atom and an oxygen atom, such as 2-vinyloxazole, 2-phenyl-4-vinyloxazole, 2-phenyl-5-vinyloxazole, 5-ethoxy-2-vinyloxazole, 3-vinyl-5-nitrosooxazole, 2-vinyl-4,5-diphenyloxazole, 2-vinyl-2-oxazoline, 4,4-dimethyl-2-vinyl-2-oxazolin-5-one, 2-vinylbenzoxazole, and 1-vinylpyridin-2(1H)-one; and ethenyl group-containing compounds having a cyclic structure containing an oxygen atom in addition to a nitrogen atom, such as 2-vinyloxazole, 2-phenyl-4-vinyloxazole, 2-phenyl-5-vinyloxazole, 5-ethoxy-2-vinyloxazole, 3-vinyl-5-nitrosooxazole, 2-vinyl-4,5-diphenyloxazole, 2-vinyl-2-oxazoline, 4,4-dimethyl-2-vinyl-2-oxazolin-5-one, 2-vinylbenzoxazole, and 1-vinylpyridin-2(1H)-one.

[0053] Examples of the α,β-unsaturated double bond group-containing compound having both a nitrogen atom and a sulfur atom as hetero atoms on the cyclic structure include vinyl group-containing compounds having a cyclic structure containing a sulfur atom in addition to a nitrogen atom, and specific examples thereof include 2-vinylthiazole, 4-methyl-5-vinylthiazole, 2-vinylbenzothiazole, 2-[2-(1-naphthyl)vinyl]benzothiazole, 2-[2-(dimethylamino)vinyl]benzothiazole, and 1-vinyl-2(1H)-pyridinethione.

[0054] In order to impart excellent adhesion to tooth structure to the dental composition, in certain embodiments (e.g., dental self-adhesive composite resins, dental cements), the dental composition preferably contains a monomer having an acidic group. By including a monomer having an acidic group in the dental composition, the adhesive strength to tooth structure can be increased. A radically polymerizable monomer is preferably used as the monomer having an acidic group. Specific examples of radically polymerizable monomers as the monomer having an acidic group include (meth)acrylate-based monomers, (meth)acrylamide-based monomers, esters of α-cyanoacrylic acid, (meth)acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, itaconic acid, etc., vinyl esters, vinyl ethers, mono-N-vinyl derivatives, and styrene derivatives. Among these, (meth)acrylate-based monomers and (meth)acrylamide-based monomers are preferred from the viewpoint of curability.

[0055] The monomer having an acidic group may be, for example, a monomer having at least one acidic group, specifically a phosphate group, a pyrophosphate group, a thiophosphate group, a phosphonate group, a carboxylic acid group, or a sulfonic acid group. The monomer having an acidic group may be used alone or in appropriate combination of two or more. Specific examples of the monomer having an acidic group are listed below.

[0056] Examples of the monomer having a phosphate group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, and 11-(meth)acryloyloxyundecyl dihydrogen phosphate. phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxydecyl]hydrogen phosphate, 1,3-di(meth)acryloyloxypropyl Examples of suitable phosphate groups include 2-(4-methoxyphenyl)-2-dihydrogenphosphate, 2-(meth)acryloyloxyethylphenylhydrogenphosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogenphosphate, 2-methacryloyloxyethyl-(4-methoxyphenyl)hydrogenphosphate, and acid chlorides, alkali metal salts, and amine salts thereof, and preferred are monomers having a divalent phosphoric acid group and an alkylene group having 6 to 12 carbon atoms.A preferred embodiment of the dental composition of the present invention is a self-adhesive dental composite resin, in which the monomer having an acidic group includes a monomer having a divalent phosphate group and an alkylene group having 6 to 12 carbon atoms.

[0057] Examples of the monomer having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl] pyrophosphate, bis[4-(meth)acryloyloxybutyl] pyrophosphate, bis[6-(meth)acryloyloxyhexyl] pyrophosphate, bis[8-(meth)acryloyloxyoctyl] pyrophosphate, bis[10-(meth)acryloyloxydecyl] pyrophosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0058] Examples of the monomer having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0059] Examples of the monomer having a phosphonic acid group include 2-(meth)acryloyloxyethyl phenylphosphonate, 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonoacetate, 10-(meth)acryloyloxydecyl-3-phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0060] Examples of the monomer having a carboxylic acid group include a (meth)acrylic acid ester having one carboxyl group or an acid anhydride group thereof in one molecule, and a (meth)acrylic acid ester having multiple carboxyl groups or acid anhydride groups thereof in one molecule.

[0061] Examples of monomers having one carboxyl group or an acid anhydride group thereof in one molecule include (meth)acrylic acid, N-(meth)acryloylglycine, N-(meth)acryloylaspartic acid, 2-(meth)acryloyloxyethyl hydrogen succinate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen maleate, O-(meth)acryloyltyrosine, and N-(meth)acryloyltyrosine. , N-(meth)acryloylphenylalanine, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-o-aminobenzoic acid, 2-(meth)acryloyloxybenzoic acid, 3-(meth)acryloyloxybenzoic acid, 4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, N-(meth)acryloyl-4-aminosalicylic acid, and compounds in which the carboxyl group of these compounds is converted to an acid anhydride group.

[0062] Examples of monomers having a plurality of carboxyl groups or acid anhydride groups thereof in one molecule include 6-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 9-(meth)acryloyloxynonane-1,1-dicarboxylic acid, 10-(meth)acryloyloxydecane-1,1-dicarboxylic acid, 11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid, 12-(meth)acryloyloxydodecane-1,1-dicarboxylic acid, 13-(meth)acryloyloxytridecane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyethyl trimellitate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxybutyl ether ... ethyl trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethyl naphthalene-1,2,6-tricarboxylic acid anhydride, 6-(meth)acryloyloxyethyl naphthalene-2,3,6-tricarboxylic acid anhydride, 4-(meth)acryloyloxyethyl carbonylpropionoyl-1,8-naphthalic acid anhydride, 4-(meth)acryloyloxyethyl naphthalene-1,8-tricarboxylic acid anhydride.

[0063] An example of a monomer having a sulfonic acid group is 2-sulfoethyl (meth)acrylate.

[0064] Furthermore, among the above-mentioned monomers having an acidic group, from the viewpoint of achieving good adhesive strength when used as a self-adhesive dental composite resin or a dental cement, it is preferable that the dental composition contains a monomer having a phosphate group or a monomer having a carboxylic acid group, and examples thereof include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyethyl dihydrogen phosphate, 9-(meth)acryloyloxypropyl dihydrogen phosphate, 10-(meth)acryloyloxybutyl dihydrogen phosphate, 11-(meth)acryloyloxypentyl dihydrogen phosphate, 12-(meth)acryloyloxyhexyl dihydrogen phosphate, 13-(meth)acryloyloxyheptyl dihydrogen phosphate, 14-(meth)acryloyloxybutyl dihydrogen phosphate, 15-(meth)acryloyloxypentyl dihydrogen phosphate, 16-(meth)acryloyloxyhexyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxybutyl dihydrogen phosphate, 19-(meth)acryloyloxybutyl dihydrogen phosphate, 20-(meth)acryloyloxyethyl dihydrogen phosphate, 21-(meth)acryloyloxypropyl dihydrogen phosphate, 22-(meth)acryloyloxybutyl dihydrogen phosphate, 23-(meth)acryloyloxybutyl dihydrogen phosphate, 24-(meth)acryloyloxybutyl dihydrogen phosphate, Acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 11-(meth)acryloyloxyundecane-1,1-Dicarboxylic acid and a mixture of 2-methacryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, and 20-(meth)acryloyloxyicosyl dihydrogen phosphate are even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being particularly preferred from the viewpoint of a balance of curability.

[0065] In one embodiment, the content of the monomer having an acidic group in the dental composition is, from the viewpoint of adhesion to tooth structure, preferably 0.1% by mass or more, more preferably 0.2% by mass or more, even more preferably 0.5% by mass or more, and particularly preferably 1% by mass or more, based on the total amount (100% by mass) of the dental composition. Furthermore, from the viewpoint of adhesion to tooth structure, the content is preferably 25% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 10% by mass or less, based on the total amount (100% by mass) of the dental composition.

[0066] (Content of Monomers (A), (A-1), and (A-2)) The total mass of the monomer (A-1) and the monomer (A-2) in the dental composition (in other words, the mass of the monomer (A)) is preferably 10 mass% or more and less than 50 mass%, more preferably 15 to 45 mass%, more preferably 20 to 42 mass%, and even more preferably 25 to 40 mass%, based on 100 mass% of the total dental composition.

[0067] The dental composition preferably contains 1 to 80 parts by mass of monomer (A-1), more preferably 5 to 75 parts by mass, even more preferably 10 to 70 parts by mass, even more preferably 15 to 65 parts by mass, even more preferably 18 to 60 parts by mass, even more preferably 18 to 53 parts by mass, even more preferably 18 to 51 parts by mass, even more preferably 18 to 50 parts by mass, and particularly preferably 20 to 50 parts by mass, based on 100 parts by mass of the total mass of monomer (A-1) and monomer (A-2). When the content of monomer (A-1) in the dental composition is within the above range, the dental composition is likely to have a high photocuring depth, and the cured product thereof is likely to have high mechanical strength, low polymerization shrinkage stress, and high surface hardness.

[0068] The dental composition preferably contains 20 to 99 parts by mass of monomer (A-2) per 100 parts by mass of the total mass of monomer (A-1) and monomer (A-2), more preferably 25 to 95 parts by mass, even more preferably 30 to 90 parts by mass, even more preferably 35 to 85 parts by mass, even more preferably 40 to 82 parts by mass, even more preferably 47 to 82 parts by mass, even more preferably 49 to 82 parts by mass, even more preferably 50 to 82 parts by mass, and particularly preferably 50 to 80 parts by mass. When the content of monomer (A-2) in the dental composition is within the above range, the dental composition is likely to have a high photocuring depth, and the cured product thereof is likely to have high mechanical strength.

[0069] In the dental composition, the ratio of the mass M1 of the monomer (A-1) to the mass M2 of the monomer (A-2) is, from the above-mentioned viewpoints, preferably 5:95 to 75:25, more preferably 10:90 to 70:30, even more preferably 15:85 to 65:35, still more preferably 18:82 to 60:40, still more preferably 18:82 to 53:47, still more preferably 18:82 to 51:49, still more preferably 18:82 to 50:50, and particularly preferably 20:80 to 50:50.

[0070] <Polymerization initiator (B)> The polymerization initiator (B) can be selected from polymerization initiators used in general industry, and among them, polymerization initiators used for dental purposes are preferably used. Among them, photopolymerization initiators are particularly preferred. The polymerization initiator (B) may be used alone or in combination of two or more.

[0071] Preferred photopolymerization initiators include, for example, (bis)acylphosphine oxides, ketals, α-diketones, and coumarin compounds.

[0072] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, and benzoyldi(2,6-dimethylphenyl)phosphonate and salts thereof (for example, sodium salt, potassium salt, ammonium salt). Examples of bisacylphosphine oxides include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide. phenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide and salts thereof (for example, sodium salts, potassium salts, and ammonium salts), sodium phenyl(2,4,6-trimethylbenzoyl)phosphinate, lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate, sodium bis(2,4,6-trimethylbenzoyl)phosphinate, and lithium bis(2,4,6-trimethylbenzoyl)phosphinate.

[0073] Among these (bis)acylphosphine oxides, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and the sodium salt of 2,4,6-trimethylbenzoylphenylphosphine oxide are particularly preferred. In some embodiments (dental self-adhesive composite resins, dental cements), sodium bis(2,4,6-trimethylbenzoyl)phosphinate and lithium bis(2,4,6-trimethylbenzoyl)phosphinate are preferred from the viewpoint of adhesion to tooth structure.

[0074] Examples of ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0075] Examples of α-diketones include diacetyl, benzyl, camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzyl, and acenaphthenequinone. Among these, camphorquinone is particularly preferred because it has a maximum absorption wavelength in the visible light region.

[0076] Examples of the coumarin compound include compounds described in JP-A-9-3109 and JP-A-10-245525, and specific examples thereof include 3,3'-carbonylbis(7-diethylaminocoumarin), 3-(4-methoxybenzoyl)coumarin, 3-thienylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin, and 3-benzoyl-1,2'-dimethoxycoumarin. coumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin), 3-benzoyl-6-bromocoumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin, 3-carboxycoumarin, 3-carboxy-7-methoxycoumarin, 3-ethoxycarbonyl-6-methoxycoumarin, 3-ethoxy Carbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin, 3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-diethylamino)coumarin, 7-methoxy-3-(4-methoxybenzoyl)coumarin, 3-(4-nitrobenzoyl)benzo[f]coumarin Phosphorus, 3-(4-ethoxycinnamoyl)-7-methoxycoumarin, 3-(4-dimethylaminocinnamoyl)coumarin, 3-(4-diphenylaminocinnamoyl)coumarin, 3-[(3-dimethylbenzothiazol-2-ylidene)acetyl]coumarin, 3-[(1-methylnaphtho[1,2-d]thiazol-2-ylidene)acetyl]coumarin, 3,3'-carbonylbis(6-methoxycoumarin), 3,3'-carbonylbis(7-acetoxycoumarin), 3,3'-carbonylbis(7-dimethylaminocoumarin), 3-(2-benzothiazoyl)-7-(diethylamino)coumarin, 3-(2-benzothiazoyl)-7-(dibutylamino)coumarin, 3-(2-benzimidazoyl)-7-(diethylamino)coumarin, 3-(2-benzothiazoyl)-7-(dioctylamino)coumarin, 3-acetyl-7-(dimethylamino)coumarin, 3,3'-carbonylbis(7-dibutylaminocoumarin), 3,3'-carbonyl-7-diethylaminocoumarin 10-[3-[4-(dimethylamino)phenyl]-1-oxo-2-propenyl]-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one, and 10-(2-benzothiazoyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one.

[0077] Among the above coumarin compounds, 3,3'-carbonylbis(7-diethylaminocoumarin) and 3,3'-carbonylbis(7-dibutylaminocoumarin) are particularly preferred.

[0078] Among the above photopolymerization initiators, (bis)acylphosphine oxides, α-diketones, and coumarin compounds have excellent photopolymerization initiation ability in the visible and near-ultraviolet regions, and therefore, polymerization can be initiated using a light source (for example, a halogen lamp, a light-emitting diode (LED), or a xenon lamp).

[0079] In some embodiments (particularly dental cements and dental core buildup materials), the dental composition may further contain a chemical polymerization initiator to enable chemical polymerization, and organic peroxides are preferably used. The organic peroxide used as the chemical polymerization initiator is not particularly limited, and known organic peroxides can be used. Representative organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, and peroxydicarbonates. Specific examples of these organic peroxides include those described in International Publication No. 2008 / 087977. A single chemical polymerization initiator may be used, or two or more may be used in combination. These chemical polymerization initiators undergo redox polymerization and harden when combined with a polymerization accelerator for chemical polymerization. The polymerization accelerator to be combined is not particularly limited, but examples include amines, sulfinic acids and their salts, benzotriazole compounds, benzimidazole compounds, sulfur-containing reducing inorganic compounds, and thiourea compounds. The polymerization accelerator may be used alone or in combination of two or more. From the viewpoint of inducing chemical polymerization, the chemical polymerization initiator and the polymerization accelerator for chemical polymerization are preferably packaged separately, and for example, a two-component paste is preferred.

[0080] The amount of the polymerization initiator (B) used is not particularly limited, but from the viewpoint of facilitating good curing of the dental composition, it is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 15 parts by mass, and even more preferably 0.3 to 10 parts by mass relative to 100 parts by mass of the total amount of the monomer (A) in the dental composition.

[0081] <Filler (C)> As the filler (C), any filler can be used as long as it does not impair the effects of the present invention, including inorganic fillers, organic fillers, and composite fillers of inorganic and organic fillers. The filler (C) may be blended singly or in combination of two or more types. The average particle size of the filler (C) is preferably 0.001 to 10 μm, more preferably 0.002 to 5 μm, even more preferably 0.003 to 3 μm, even more preferably 0.004 to 1 μm, and even more preferably 0.005 to 0.8 μm. The average particle size of the filler (C) refers to the average primary particle size determined by laser diffraction scattering or electron microscope observation of the particles, as described below.

[0082] Examples of inorganic fillers include amorphous inorganic particles and inorganic ultrafine particles. Examples of amorphous inorganic particles include various glasses (mainly composed of silica and optionally containing oxides of heavy metals, boron, aluminum, etc., such as dental glass powders such as E-glass, barium glass (manufactured by Schott, trade names "GM27884" and "GM8235"), and ESSTECH, trade names "E2000" and "E3000"), and lanthanum glass ceramics (manufactured by Schott, trade name "GM31684")), various ceramics, composite oxides such as silica-titania and silica-zirconia, kaolin, clay minerals (such as montmorillonite), mica, ytterbium fluoride, silica-coated ytterbium fluoride (manufactured by Sukgyung AT, trade name "SG-YBF100WSCMP10"), and yttrium fluoride. Examples of inorganic ultrafine particles include inorganic oxide particles such as silica, alumina, titania, zirconia, etc., or composite oxide particles made of these, as well as particles of calcium phosphate, hydroxyapatite, yttrium fluoride, ytterbium fluoride, barium titanate, potassium titanate, etc. Preferred are particles of silica, alumina, titania, silica / alumina composite oxide, and silica / zirconia composite oxide produced by flame pyrolysis, such as those available under the trade names "Aerosil (registered trademark) 50," "Aerosil (registered trademark) 130," "Aerosil (registered trademark) 380," "Aerosil (registered trademark) OX50," "Aeroxide (registered trademark) AluC," and "Aeroxide (registered trademark) TiO," all of which are manufactured by Nippon Aerosil Co., Ltd. ２ P25," "VP Zirconium Oxide 3-YSZ," and "VP Zirconium Oxide 3-YSZPH." In this specification, when the inorganic filler is surface-treated as described below, the average particle size of the inorganic filler refers to the average particle size before the surface treatment.

[0083] The inorganic ultrafine particles can also be used in the form of aggregated particles formed by the aggregation of inorganic ultrafine particles. Usually, commercially available inorganic ultrafine particles exist as aggregates, but when 10 mg of inorganic ultrafine particle powder is added to 300 mL of water or water (dispersion medium) containing 5 mass % or less of a surfactant such as sodium hexametaphosphate, and dispersed for 30 minutes with an ultrasonic intensity of 40 W and a frequency of 39 kHz, the aggregated particles have such a weak cohesion that they are dispersed to the particle size indicated by the manufacturer. However, the aggregated particles that can be used as the filler (C) may be those that are strongly aggregated together and hardly dispersible even under such conditions.

[0084] A suitable method for producing strongly agglomerated particles from commercially available inorganic ultrafine particles is to heat the inorganic ultrafine particles to a temperature close to just before they melt, so that the inorganic ultrafine particles in contact with each other are slightly fused together, in order to further increase the agglomeration force. In this case, the agglomerated form may be formed before heating in order to control the shape of the agglomerated particles. For example, the inorganic ultrafine particles may be placed in a suitable container and pressurized, or dispersed in a solvent and then the solvent removed by a method such as spray drying.

[0085] Furthermore, another suitable method for producing aggregates of inorganic ultrafine particles is to use silica sol, alumina sol, titania sol, zirconia sol, etc. produced by a wet method, and dry the sol by methods such as freeze drying or spray drying, followed by heat treatment as necessary, to easily obtain aggregated particles in which the particles are firmly aggregated together. Specific examples of sols include "Seahoster" (manufactured by Nippon Shokubai Co., Ltd.), "OSCAL" and "QUEEN TITANIC" (manufactured by JGC Catalysts and Chemicals Co., Ltd.), and "Snowtex," "Alumina Sol," "Celnax," and "Nanouse" (manufactured by Nissan Chemical Industries, Ltd.). The shape of the inorganic ultrafine particles is not particularly limited, and can be appropriately selected and used. Alternatively, commercially available aggregates of inorganic ultrafine particles can be used as they are. Examples include "Silica Microbead P-500" and "Silica Microbead P-1500" (manufactured by JGC Catalysts and Chemicals Co., Ltd.), and silica-zirconia (manufactured by Sukgyung AT Co., Ltd., product name "SG-SZ200G151CMP8").

[0086] Examples of organic fillers include polymethyl methacrylate, polyethyl methacrylate, polyfunctional methacrylate polymers, polyamide, polystyrene, polyvinyl chloride, chloroprene rubber, nitrile rubber, and styrene-butadiene rubber.

[0087] Examples of composite fillers of inorganic and organic fillers include those in which inorganic fillers are dispersed in organic fillers, and inorganic / organic composite fillers in which inorganic fillers are coated with various polymers.

[0088] In order to improve the curability, mechanical strength, and handleability, the filler may be surface-treated in advance with a known surface treatment agent (for example, a silane coupling agent) before use. Examples of surface treatment agents include methacryloyloxymethyltrimethoxysilane, 2-methacryloyloxyethyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 4-methacryloyloxybutyltrimethoxysilane, 5-methacryloyloxypentyltrimethoxysilane, 6-methacryloyloxyhexyltrimethoxysilane, methacryloyloxyoctyltrimethoxysilane, 9-methacryloyloxynonyltrimethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, 11-methacryloyloxyundecyldichloromethylsilane, 11-methacryloyloxyundecyltrichlorosilane, 11-methacryloyloxyundecyldimethoxymethylsilane, 12-methacryloyloxydodecyltrimethoxysilane, and 13-methacryloyloxytridecyltrimethoxysilane.

[0089] The average particle size (average primary particle size) can be determined by laser diffraction scattering or electron microscope observation of the particles. Specifically, laser diffraction scattering is convenient for measuring the particle size of particles with an average particle size of 0.1 μm or more, while electron microscope observation is convenient for measuring the particle size of ultrafine particles with an average particle size of less than 0.1 μm. For laser diffraction scattering, for example, a 0.2% aqueous solution of sodium hexametaphosphate can be used as a dispersion medium and measurements can be made on a volume basis using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation). For electron microscope observation, a scanning electron microscope (e.g., SU3800, S-4000, manufactured by Hitachi High-Technologies Corporation) can be used. For electron microscope observation, an electron microscope photograph of the particles can be taken and the particle sizes of particles (200 or more) observed within a unit field of view of the photograph can be determined using image analysis particle size distribution measurement software (Mac-View (Mountec Co., Ltd.)). In this case, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average primary particle diameter is calculated from the number of particles and their particle diameters.

[0090] As described above, the content of the filler (C) is 50% by mass to 90% by mass relative to 100% by mass of the total dental composition. From the viewpoints of paste workability and the mechanical strength of the cured product, it is preferably 55% by mass to 85% by mass, more preferably 58% by mass to 80% by mass, and even more preferably 60% by mass to 75% by mass. Furthermore, from the viewpoints of paste workability and the mechanical strength of the cured product, the content of the filler (C) is preferably 50% by mass to 1,000 parts by mass, more preferably 100% by mass to 500 parts by mass, and even more preferably 100% by mass to 300 parts by mass relative to 100 parts by mass of the total amount of the monomer (A) in the dental composition. Within these ranges, it is possible to obtain a cured product that is excellent in both mechanical strength and surface hardness.

[0091] <Polymerization Accelerator (D)> The dental composition according to an embodiment of the present invention may contain a polymerization accelerator (D). Examples of the polymerization accelerator (D) include amines, sulfinic acids (including salts), barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds. One type of polymerization accelerator (D) may be used alone, or two or more types may be used in combination.

[0092] The amines are divided into aliphatic amines and aromatic amines. Examples of the aliphatic amines include primary aliphatic amines, secondary aliphatic amines, and tertiary aliphatic amines. Examples of primary aliphatic amines include n-butylamine, n-hexylamine, and n-octylamine. Examples of secondary aliphatic amines include diisopropylamine, dibutylamine, and N-methylethanolamine. Examples of tertiary aliphatic amines include N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, from the viewpoint of the hardenability and storage stability of the dental composition, tertiary aliphatic amines are preferred, and N-methyldiethanolamine and triethanolamine are more preferred.

[0093] Examples of the aromatic amine include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis(2-hydroxyethyl)-4-ethylaniline, N,N-bis(2-hydroxyethyl)-4-isopropylaniline, N,N-bis(2-hydroxyethyl)-4-t-butylaniline, N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, and N,N-dimethyl-m-toluidine. , N,N-diethyl-p-toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, N,N-dimethyl-3,5-di-t-butylaniline, 4-(N,N-dimethylamino)ethyl benzoate, 4-(N,N-dimethylamino)methyl benzoate, 4-(N,N-dimethylamino)benzoic acid 2-butoxyethyl, 4-(N,N-dimethylamino)benzoic acid 2-((meth)acryloyloxy)ethyl, 4-(N,N-dimethylamino)benzophenone, 4-(N,N-dimethylamino)butyl benzoate. Among these, N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, 2-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone are preferred from the viewpoint of imparting excellent curability to the dental composition.

[0094] Examples of the sulfinic acids include p-toluenesulfinic acid, sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic acid, sodium benzenesulfinate, potassium benzenesulfinate, lithium benzenesulfinate, calcium benzenesulfinate, 2,4,6-trimethylbenzenesulfinic acid, sodium 2,4,6-trimethylbenzenesulfinate, potassium 2,4,6-trimethylbenzenesulfinate, lithium 2,4,6-trimethylbenzenesulfinate, and 2,4,6-trimethylbenzenesulfinate. Examples of suitable sulfonylbenzenesulfinates include calcium benzenesulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate, potassium 2,4,6-triethylbenzenesulfinate, lithium 2,4,6-triethylbenzenesulfinate, calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, and calcium 2,4,6-triisopropylbenzenesulfinate. Among these, sodium benzenesulfinate, sodium p-toluenesulfinate, and sodium 2,4,6-triisopropylbenzenesulfinate are particularly preferred.

[0095] Examples of the barbituric acid derivatives include barbituric acid, 1,3-dimethylbarbituric acid, 1,3-diphenylbarbituric acid, 1,5-dimethylbarbituric acid, 5-butylbarbituric acid, 5-ethylbarbituric acid, 5-isopropylbarbituric acid, 5-cyclohexylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-5-n-butylbarbituric acid, 1,3-dimethyl-5-isobutylbarbituric acid, 1,3-dimethyl-5-cyclopentylbarbituric acid, 1,3-dimethyl-5-cyclohexylbarbituric acid, 1,3-dimethyl-5-phenylbarbituric acid, 1 ...phenylbarbituric acid, 1-cyclohexylbarbituric acid, 1,3-dimethyl-5-n-butylbarbituric acid, 1,3-dimethyl-5-isobutylbarbituric acid, 1,3-dimethyl-5-cyclo Examples thereof include 1-cyclohexyl-1-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, 5-methylbarbituric acid, 5-propylbarbituric acid, 1,5-diethylbarbituric acid, 1-ethyl-5-methylbarbituric acid, 1-ethyl-5-isobutylbarbituric acid, 1,3-diethyl-5-butylbarbituric acid, 1-cyclohexyl-5-methylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-cyclohexyl-5-octylbarbituric acid, 1-cyclohexyl-5-hexylbarbituric acid, 5-butyl-1-cyclohexylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, thiobarbituric acids, and salts thereof. Examples of salts of these barbituric acid derivatives include alkali metal salts and alkaline earth metal salts, and more specific examples include sodium 5-butylbarbiturate, sodium 1,3,5-trimethylbarbiturate, and sodium 1-cyclohexyl-5-ethylbarbiturate.

[0096] Particularly preferred barbituric acid derivatives are 5-butylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and sodium salts thereof.

[0097] Examples of the triazine compound include 2,4,6-tris(trichloromethyl)-s-triazine, 2,4,6-tris(tribromomethyl)-s-triazine, 2-methyl-4,6-bis(trichloromethyl)-s-triazine, 2-methyl-4,6-bis(tribromomethyl)-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(p-methylthiophenyl)-4,6-bis(trichloromethyl)-s-triazine. 2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(2,4-dichlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-bromophenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-n-propyl-4,6-bis(trichloromethyl)-s-triazine, 2-(α,α,β-trichloroethyl)-4,6-bis(trichloromethyl)-s-triazine, 2-styryl-4,6- Bis(trichloromethyl)-s-triazine, 2-[2-(p-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(o-methoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(p-butoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(3,4-dimethoxyphenyl)ethenyl]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-(3,4,5-trimethoxyphenyl)ethenyl]-4, 6-bis(trichloromethyl)-s-triazine, 2-(1-naphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-biphenylyl)-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N,N-bis(2-hydroxyethyl)amino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-ethylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-methylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N-hydroxyethyl-N-methylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine, 2-[2-{N,N-diallylamino}ethoxy]-4,6-bis(trichloromethyl)-s-triazine,

[0098] Among these triazine compounds, 2,4,6-tris(trichloromethyl)-s-triazine is preferred in terms of polymerization activity, and 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(p-chlorophenyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(4-biphenylyl)-4,6-bis(trichloromethyl)-s-triazine are preferred in terms of storage stability. The triazine compounds may be used alone or in combination of two or more.

[0099] Examples of the copper compound include copper acetylacetonate, copper (II) acetate, copper oleate, copper (II) chloride, and copper (II) bromide.

[0100] Examples of the tin compound include di-n-butyltin dimaleate, di-n-octyltin dimaleate, di-n-octyltin dilaurate, and di-n-butyltin dilaurate. Among these, di-n-octyltin dilaurate and di-n-butyltin dilaurate are preferred.

[0101] The vanadium compound is preferably a tetravalent or pentavalent vanadium compound, such as divanadium(IV) tetroxide, vanadium oxide acetylacetonate(IV), vanadyl(IV) oxalate, vanadyl(IV) sulfate, oxobis(1-phenyl-1,3-butanedionato)vanadium(IV), bis(maltolate)oxovanadium(IV), vanadium(V) pentoxide, sodium(V) metavanadate, and ammonium(V) metavanadate.

[0102] Examples of the halogen compounds include dilauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltrimethylammonium chloride, tetramethylammonium chloride, benzyldimethylcetylammonium chloride, and dilauryldimethylammonium bromide.

[0103] Examples of the aldehydes include terephthalaldehyde and benzaldehyde derivatives. Examples of the benzaldehyde derivatives include dimethylaminobenzaldehyde, p-methyloxybenzaldehyde, p-ethyloxybenzaldehyde, and p-n-octyloxybenzaldehyde. Among these, p-n-octyloxybenzaldehyde is preferred from the viewpoint of curability.

[0104] Examples of the thiol compound include 3-mercaptopropyltrimethoxysilane, 2-mercaptobenzoxazole, decanethiol, and thiobenzoic acid.

[0105] Examples of the sulfite include sodium sulfite, potassium sulfite, calcium sulfite, and ammonium sulfite.

[0106] Examples of the hydrogen sulfite include sodium hydrogen sulfite and potassium hydrogen sulfite.

[0107] Examples of the thiourea compound include 1-(2-pyridyl)-2-thiourea, thiourea, methylthiourea, ethylthiourea, N,N'-dimethylthiourea, N,N'-diethylthiourea, N,N'-di-n-propylthiourea, N,N'-dicyclohexylthiourea, trimethylthiourea, triethylthiourea, tri-n-propylthiourea, tricyclohexylthiourea, tetramethylthiourea, tetraethylthiourea, tetra-n-propylthiourea, and tetracyclohexylthiourea.

[0108] The content of the polymerization accelerator (D) in the dental composition is not particularly limited, but from the viewpoint of the curability of the resulting dental composition, it is preferably 0.1 to 20 parts by mass, more preferably 0.2 to 15 parts by mass, and even more preferably 0.2 to 10 parts by mass relative to 100 parts by mass of the total amount of the monomer (A) in the dental composition.

[0109] <Other Components> The dental composition according to the embodiment of the present invention may contain known additives within a range that does not result in performance below a practically usable level. Examples of such additives include polymerization inhibitors, antioxidants, colorants (pigments, dyes), UV absorbers, solvents (e.g., water, organic solvents), and thickeners. One type of additive may be used alone, or two or more types may be used in combination. In one embodiment, the content of solvents (e.g., water, organic solvents) in the dental composition is preferably less than 1% by mass, more preferably less than 0.1% by mass, and even more preferably less than 0.01% by mass, based on the total amount of the dental composition.

[0110] Examples of polymerization inhibitors include hydroquinone, hydroquinone monomethyl ether, dibutylhydroquinone, dibutylhydroquinone monomethyl ether, t-butylcatechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, and 3,5-di-t-butyl-4-hydroxytoluene. The content of the polymerization inhibitor is preferably 0.001 to 1.0 part by mass per 100 parts by mass of the total amount of monomers in the dental composition.

[0111] The total mass of the other additives in the dental composition is not particularly limited as long as the effects of the present invention are achieved, but from the viewpoint of more easily achieving the effects of the present invention, the total mass of the other additives in the dental composition is preferably 20% by mass or less, more preferably 15% by mass or less, even more preferably 10% by mass or less, still more preferably 5% by mass or less, and still more preferably 2% by mass or less, relative to 100% by mass of the dental composition. In other words, the mass of the other additives in the dental composition is preferably 0 to 20% by mass, relative to 100% by mass of the dental composition.

[0112] <Total Content of Components (A) to (C)> The total mass of the monomer (A), polymerization initiator (B), and filler (C) in the dental composition is preferably 90% by mass or more, more preferably 95% by mass or more, even more preferably 98% by mass or more, and even more preferably 99% by mass or more, and may be 100% by mass, from the viewpoints of ensuring a desired photocuring depth and enabling the cured product to exhibit a desired polymerization shrinkage stress and mechanical strength. In other words, the total mass of the monomer (A), polymerization initiator (B), and filler (C) in the dental composition is preferably 90 to 100% by mass.

[0113] [Method for Producing Dental Composition] When producing the dental composition, for example, the order of adding the components or the mixing method are not particularly limited, and the dental composition can be produced by a method known to those skilled in the art. A preferred method is to mix the components other than the filler (C) and then add the filler (C) and mix them.

[0114] [Use of Dental Composition] In one embodiment, the dental composition is a dental composite resin. In another embodiment, the dental composition is a dental cement. In yet another embodiment, the dental composition is a self-adhesive dental composite resin. In another embodiment, the dental composition is a dental core build-up material.

[0115] The dental composition may be a one-component type or a two-component type. In the case of a two-component type, for example, specific components may be packaged separately in the first and second components to enhance storage stability.

[0116] <Physical Properties of Dental Composition> (Polymerization Shrinkage Stress) The dental composition preferably has a low polymerization shrinkage stress from the viewpoint of easily obtaining a desired shape. More specifically, the dental composition is filled into a stainless steel washer having an inner diameter of 5.3 mm and a thickness of 0.8 mm, and cured by irradiating light. The polymerization shrinkage stress measured with a universal testing machine is preferably 12.0 MPa or less, more preferably 9.7 MPa or less, even more preferably 9.5 MPa or less, even more preferably 8.5 MPa or less, even more preferably 8.0 MPa or less, and particularly preferably 7.5 MPa or less. There is no particular lower limit, but from the viewpoint of the mechanical strength of the cured product, it is, for example, 3.5 MPa or more. In other words, the polymerization shrinkage stress of the dental composition is preferably 3.5 to 10.0 MPa. The polymerization shrinkage stress is measured in detail by the method described in the Examples section below. The polymerization shrinkage stress is set within the above range by, for example, selecting and adjusting at least one element selected from the group consisting of the type of monomer (A), the amount of monomer (A), the type of polymerization initiator (B), the amount of polymerization initiator (B), the type of filler (C), and the amount of filler (C).

[0117] (Flexural Modulus and Flexural Strength) The cured product of the dental composition preferably has a high flexural modulus and flexural strength so as to be sufficiently durable against the bite of hard foods, etc. The flexural modulus of the dental composition, calculated from the results of a flexural strength test measured in accordance with ISO 4049:2019, is preferably 4.0 GPa or more, more preferably 5.0 GPa or more, even more preferably 7.0 GPa or more, still more preferably 7.5 GPa or more, and even more preferably 8.0 GPa or more. There is no particular upper limit, but from the viewpoint of ease of production, it is, for example, 20 GPa or less. In other words, the flexural modulus of the cured product of the dental composition is preferably 4.0 to 20 GPa. The flexural strength of the dental composition, measured in accordance with ISO 4049:2019, is preferably 100 MPa or more, more preferably 110 MPa or more, even more preferably 120 MPa or more, even more preferably 125 MPa or more, and even more preferably 130 MPa or more. While there is no particular upper limit, from the viewpoint of paste handleability, etc., it is, for example, 200 MPa or less. In other words, the flexural strength of the cured product of the dental composition is preferably 100 to 200 MPa. The flexural modulus and flexural strength are measured in detail by the method described in the Examples section below. The flexural modulus and flexural strength can be set within the above ranges by, for example, selecting and adjusting at least one element selected from the group consisting of the type of monomer (A), the amount of monomer (A), the type of polymerization initiator (B), the amount of polymerization initiator (B), the type of filler (C), and the amount of filler (C).

[0118] (Vickers Hardness) The cured product of the dental composition preferably has a high surface hardness to easily prevent damage due to contact with foreign matter. More specifically, the surface of the cured product obtained by irradiating the dental composition with light is mirror-polished, and the Vickers hardness value measured on the surface using a microhardness tester is preferably 30 Hv or more, more preferably 35 Hv or more, even more preferably 40 Hv or more, and even more preferably 45 Hv or more. There is no particular upper limit, but from the viewpoint of paste handleability, etc., it is, for example, 100 Hv or less. In other words, the Vickers hardness of the dental composition is preferably 30 to 100 Hv. The Vickers hardness is measured in detail by the method described in the Examples below. The Vickers hardness is set within the above range by, for example, selecting and adjusting at least one element selected from the group consisting of the type of monomer (A), the amount of monomer (A), the type of polymerization initiator (B), the amount of polymerization initiator (B), the type of filler (C), and the amount of filler (C).

[0119] (Photocuring Depth) The dental composition preferably has a large photocuring depth from the viewpoint of facilitating curing. More specifically, the value measured in accordance with ISO 4049:2019 is preferably 3.0 mm or more, more preferably 3.5 mm or more, even more preferably 4.0 mm or more, even more preferably 4.5 mm or more, even more preferably 5.0 mm or more, and particularly preferably 5.5 mm or more. There is no particular upper limit, but from the viewpoint of paste handleability, etc., it is, for example, 5.9 mm or less. In other words, the photocuring depth of the dental composition is preferably 3.0 to 5.9 mm. The photocuring depth is measured in detail by the method described in the Examples below. The photocuring depth is set within the above range by, for example, selecting and adjusting at least one element selected from the group consisting of the type of monomer (A), the amount of monomer (A), the type of polymerization initiator (B), the amount of polymerization initiator (B), the type of filler (C), and the amount of filler (C).

[0120] Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to these examples in any way.

[0121] Each component used in the examples and comparative examples will be explained below together with its abbreviation.

[0122] [Monomer (A)] <Monomer (A-1)> "1-NMMA": 1-naphthylmethyl methacrylate "1-NMA": 1-naphthylmethyl acrylate <Monomer (A-2)> "UDMA": 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) "POB-MA": m-phenoxybenzyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd.) "D-2.6E": 2,2-bis[4-(meth)acryloyloxypolyethoxyphenyl]propane "3G": triethylene glycol dimethacrylate "THF-MA": tetrahydrofurfuryl methacrylate "MDP": 10-(meth)acryloyloxydecyl dihydrogen phosphate [Polymerization initiator (B)] "CQ": camphorquinone "TMDPO": 2,4,6-trimethylbenzoyldiphenylphosphine oxide [Filler (C)] "Filler 1": surface-treated SiO prepared by the procedure described below ２ Treated silica "Filler 2": Surface-treated BaO filler prepared by the procedure described below "Filler 3": Commercially available surface-treated SiO ２ -ZrO ２ Agglomerated filler "Filler 4": commercially available surface-treated SiO ２ Coat YbF ３ [Polymerization accelerator (D)] "DABE": ethyl 4-(N,N-dimethylamino)benzoate [Others] "BHT": 3,5-di-t-butyl-4-hydroxytoluene

[0123] [Preparation of filler] <Filler 1> 100 g of Ar130 (hydrophilic fumed silica, ultrafine silica "Aerosil (registered trademark) 130", average particle size: 16 nm, refractive index: 1.46, manufactured by Nippon Aerosil Co., Ltd.), 30 g of 3-methacryloyloxypropyltrimethoxysilane, and 200 mL of a 0.3 mass % aqueous acetic acid solution were placed in a three-necked flask and stirred for 2 hours under ultrasonic dispersion at room temperature. After removing water by freeze-drying, a surface-treated SiO was obtained by heat treatment at 90°C for 3 hours.２ Treated silica was prepared and used as Filler 1.

[0124] <Filler 2> 100 parts by mass of barium glass (product name: GM27884, average primary particle size 0.18 μm, manufactured by Schott), 11 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, and 500 mL of 0.5% aqueous acetic acid solution were placed in a three-neck flask and stirred for 2 hours under ultrasonic dispersion at room temperature. After removing water by freeze-drying, the mixture was heat-treated at 90°C for 3 hours to produce a surface-treated BaO filler. This was used as Filler 2.

[0125] <Filler 3> Commercially available surface-treated SiO ２ -ZrO ２ An aggregated filler (SG-SZ200G151CMP8, average particle size of primary particles: 200 nm, average particle size of secondary particles: 5.2 μm, refractive index: 1.51, manufactured by Sukgyung AT) was used as filler 3.

[0126] <Filler 4> Commercially available surface-treated SiO ２ Coat YbF ３ (SG-YBF100WSCMP10, average particle size of primary particles: 110 nm, average particle size of secondary particles: 1.2 μm, refractive index: 1.53, manufactured by Sukgyung AT) was used as filler 4.

[0127] Examples 1 to 11 and Comparative Examples 1 to 6 The dental compositions of Examples 1 to 11 and Comparative Examples 1 to 5 were prepared by mixing the components listed in the "Filler" column (except for the "Filler" column) at room temperature (25°C) and then adding the components listed in the "Filler" column and further mixing. All of these compositions were paste-like and had fluidity suitable for filling, plugging, or coating teeth. In Comparative Example 6, Filler 2 was added to the dental composition of Example 1 to increase the filler content, thereby attempting to prepare a dental composition with a total filler content of over 90% by mass. However, producing such a dental composition was difficult. The polymerization shrinkage stress, flexural modulus, flexural strength, Vickers hardness, and photocuring depth of the dental compositions of each Example and Comparative Example were measured or evaluated as follows.

[0128] <Polymerization shrinkage stress> A dental ceramic adhesive (trade name "Clearfil (registered trademark) Ceramic Primer Plus", manufactured by Kuraray Noritake Dental Co., Ltd.) was applied as a pretreatment material to a 5.0 mm thick glass plate sandblasted with 50 μm alumina powder, and then dried with an air blower. A dental adhesive (trade name "Clearfil (registered trademark) Megabond (registered trademark) 2 Bond", manufactured by Kuraray Noritake Dental Co., Ltd.) was applied to a separately prepared stainless steel washer (inner diameter 5.3 mm × 0.8 mm thickness) coated with a release agent, without leaving any excess, and the washer was tightly attached to the glass plate. The side of the glass plate not in contact with the washer was irradiated with light using a dental visible light irradiator (Pencure 2000, manufactured by Morita Corporation) in standard mode for 10 seconds to cure the dental adhesive, thereby fixing the washer and the glass plate. Next, to fix the dental composition to the glass plate, a dental adhesive (trade name "Clearfil (registered trademark) Megabond (registered trademark) 2 Bond" manufactured by Kuraray Noritake Dental Co., Ltd.) was applied to the inside of the washer, and the washer was irradiated with light for 10 seconds in standard mode using a dental visible light irradiator (Pencure 2000 manufactured by Morita Corporation). The washer was then filled with the paste-like dental compositions prepared in the Examples and Comparative Examples. A separately sandblasted stainless steel jig (φ5 ​​mm) was prepared, and a dental adhesive (trade name "Clearfil (registered trademark) Megabond (registered trademark) 2 Bond") was applied. The coated side was irradiated with light for 10 seconds in standard mode using a dental visible light irradiator (Pencure 2000 manufactured by Morita Corporation). After the light irradiation, the dental composition in the washer was sandwiched between the stainless steel jig and the glass plate, and excess dental composition was removed. The dental composition filled in the washer was irradiated with light from the glass plate side using a dental LED light irradiator (manufactured by Morita Corporation, product name "PenCure 2000") in standard mode for 10 seconds to cure the dental composition, and the stress applied 3 minutes after the start of light irradiation was measured as polymerization shrinkage stress using a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) (n=3). The arithmetic mean value was then calculated to determine the polymerization shrinkage stress of each dental composition.

[0129] <Flexural Modulus and Flexural Strength> Flexural modulus and flexural strength were evaluated by a bending test in accordance with ISO 4049:2019. Specifically, the procedure is as follows. The paste-like dental compositions prepared in the Examples and Comparative Examples were filled into a SUS mold (2 mm long x 25 mm wide x 2 mm thick), and the top and bottom of the paste (2 mm x 25 mm surfaces) were pressed against a glass slide. Next, in the pressed state, a dental visible light irradiator (PenCure 2000, manufactured by Morita Corporation) was used through the glass slide to irradiate the paste from above and below in standard mode for 10 seconds each at five locations on each side (a total of 50 seconds of light irradiation per side), thereby curing the paste and obtaining a cured product. Five cured products were prepared for each Example and Comparative Example. The cured product was immersed in distilled water in a container and left in an incubator set at 37°C for 24 hours. Thereafter, the three-point bending strength and bending modulus were measured (n=5) using a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) at a support distance of 20 mm and a crosshead speed of 1 mm / min, and the arithmetic mean values ​​were calculated to represent the bending strength and bending modulus of the cured product of each dental composition.

[0130] <Vickers Hardness> The dental composition of each Example and Comparative Example was filled into a syringe, and the paste was filled into a polytetrafluoroethylene mold with a 10 mm diameter x 5 mm hole, and pressed against a polypropylene film. A dental visible light irradiator (Morita Corporation, Pencure 2000) was attached to the polypropylene film and irradiated in normal mode for 10 seconds to produce a cured product (n = 1). The clean, smooth surface of the cured product was polished under dry conditions using #1500 abrasive paper, and finally mirror-polished with diamond paste to obtain a test specimen. The Vickers hardness (Hv) was measured on the surface of this test specimen using a microhardness tester (HM-221, Mitutoyo Corporation) by applying a load of 200 g for 10 seconds. The measurement was performed at five locations, one at the center of the cured product and four locations around it, and the arithmetic mean value of the measured values ​​at these five locations was used as the Vickers hardness of the dental composition of each Example and Comparative Example.

[0131] <Photocure Depth> The photocure depth was evaluated in accordance with ISO 4049:2019. Specifically, the procedure was as follows. The dental compositions prepared in the Examples and Comparative Examples were filled into a stainless steel mold (12 mm thick, 4 mm diameter). The top and bottom surfaces were laminated and pressed together in the order of film and slide glass. The glass plate was removed from one side, and the pressed-together surface of the film was irradiated with light for 10 seconds using a dental visible light irradiator "PenCure 2000" (manufactured by Morita Corporation) to cure the film. After removing the resulting cured product from the mold, the uncured portion was wiped off, and the thickness of the remaining cured product was measured using a micrometer (manufactured by Mitutoyo Corporation). The distance from the light-irradiated surface to the cured product was calculated. Half of this calculated value was used as the photocure depth (n = 5). The arithmetic mean value was then calculated to determine the photocure depth of the dental compositions of the Examples and Comparative Examples.

[0132] The measurement and evaluation results of the dental compositions of the Examples and Comparative Examples, along with their compositions, are shown in the following Table 1. In Table 1, a "-" in the "Composition" column means that the corresponding component was not blended.

[0133]

[0134] As shown in Table 1, the cured products obtained by curing the dental compositions of Examples 1 to 11 had high flexural strength and high Vickers hardness. In particular, the dental compositions of Examples 2, 6, 8, and 9 produced cured products with high flexural strength exceeding 130 MPa. The cured products obtained by curing the dental compositions of Examples 5, 6, and 9 also had high flexural moduli of 8.7 GPa or more. The cured products obtained by curing the dental compositions of Examples 2, 3, and 7 to 9 also had high Vickers hardness exceeding 40 Hv. The cured products obtained by curing the dental compositions of Examples 1 to 4, 7, 10, and 11 also had polymerization shrinkage stresses of less than 8.0 MPa.

[0135] On the other hand, as shown in Table 1, the cured products obtained by curing the dental compositions of Comparative Examples 1 to 4, which did not contain monomer (A-1), were inferior in at least one of the Vickers hardness and polymerization shrinkage stress properties to the cured products of the dental compositions of the Examples. For example, Comparative Example 1 had a lower Vickers hardness than all the Examples, and Comparative Example 4 had a lower polymerization shrinkage stress than all the Examples. Furthermore, because the dental compositions of Comparative Examples 2 and 3 did not contain monomer (A-1), the cured products were more brittle than the dental composition of Example 4, making it difficult to measure the polymerization shrinkage stress. Furthermore, the Vickers hardness of these cured products was significantly inferior. The dental composition of Comparative Example 5 contained less than 50% filler (C), and therefore had lower flexural modulus and Vickers hardness than the dental compositions of the Examples. Furthermore, the cured products were brittle, making it difficult to measure the polymerization shrinkage stress.

[0136] The dental composition of the present invention can be used for any dental restoration. Furthermore, since the dental composition of the present invention has a small refractive index difference with respect to the filler and a high photocuring depth, it is easy to impart high mechanical strength to the cured product. Therefore, the dental composition can be suitably used for dental composite resins, self-adhesive dental composite resins, dental cements, and dental core build-up materials. This application is based on a Japanese patent application (Patent Application No. 2023-209300) filed on December 12, 2023, the entire contents of which are incorporated by reference.

Claims

1. A dental composition comprising a monomer (A), a polymerization initiator (B), and a filler (C), wherein the monomer (A) comprises a monomer (A-1) represented by the following formula (1) and a monomer (A-2) other than the monomer (A-1), and the dental composition comprises 50 to 90% by mass of the filler (C) relative to a total mass of 100% by mass of the dental composition. [In the above formula (1), R １ represents a hydrogen atom or a methyl group, R ２ represents a divalent hydrocarbon group, R ３ represents an oxygen atom or a sulfur atom. ４ and R ５ Each independently represents a halogen atom, an alkyl group, or an alkoxy group. m represents 0 or 1, n represents 0 or 1, p represents 0 to 3, and q represents 0 to 4. However, when m is 0, n represents 0. When p is 2 or more, a plurality of R ４ are the same atom or group, or different atoms or groups. When q is 2 or more, a plurality of R ５ are the same atom or group, or are different atoms or groups.

2. The dental composition according to claim 1, comprising 1 to 80 parts by mass of monomer (A-1) per 100 parts by mass of the total of monomer (A-1) and monomer (A-2).

3. The dental composition according to claim 1 or 2, wherein the monomer (A-1) is a monomer (A-1a) represented by the following formula (2): [In the formula (2), R １ , R ２ , R ３ , m, and n are the same as defined in formula (1).

4. The dental composition according to claim 1 or 2, wherein the monomer (A-1) is 1-naphthylmethyl (meth)acrylate.

5. The dental composition according to claim 1 or 2, wherein the monomer (A-2) includes a monomer having a urethane bond.

6. The dental composition according to claim 1 or 2, wherein the monomer (A-2) includes a monomer having a (meth)acryloyl group.

7. A dental composition according to claim 1 or 2, in which the content of a monomer having a bisphenol A skeleton is more than 0% by mass and not more than 30% by mass, or which does not contain a monomer having a bisphenol A skeleton.

8. The dental composition according to claim 1 or 2, wherein the dental composition is a dental composite resin.

9. The dental composition according to claim 1 or 2, wherein the dental composition is a dental cement.

10. The dental composition of claim 1 or 2, wherein the dental composition is a self-adhesive dental composite resin.

11. The dental composition according to claim 1 or 2, which is a dental core construction material.

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