Two-component dental composition

Abstract

The present invention provides a two-component dental composition showing minimal color change and having excellent long-term color stability. The present invention relates to a two-component dental composition comprising an ultraviolet absorbent (A), a polymerizable monomer (B), a chemical polymerization initiator (C), and a chemical polymerization promoter (D). The ultraviolet absorbent (A) is a triazine-based ultraviolet absorbent having a maximum absorption wavelength in the wavelength range from 310 nm to 400 nm. The ultraviolet absorbent (A) is preferably a triazine-based ultraviolet absorbent represented by general formula (1).

Description

Two-component dental composition

[0001] The present invention relates to a two-component dental composition, and more particularly to a two-component dental composition that exhibits minimal color change and long-term color stability.

[0002] Adhesive materials are used for the repair and treatment of wet bodies, such as biological hard tissues such as teeth and bones. Resin-based dental curable compositions comprising radical polymerizable monomers, polymerization initiators, etc. are commonly used as adhesive materials for wet bodies.

[0003] Teeth that have lost their function due to caries or accidents are repaired by, for example, fixing metal or ceramic dental crown restorative materials called inlays or crowns to the teeth, and adhesives called dental cements are used to fix dental crown restorative materials to the teeth.

[0004] Furthermore, when repairing tooth tissue that has been damaged by caries or other causes, if the damage is small, the mainstream method is to fill the damaged area with a paste of a repair material, generally called a filling composite resin, whose main components are a (meth)acrylate-based radically polymerizable monomer and an inorganic filler such as a metal oxide, and then give it the shape of a tooth, followed by polymerization and hardening.

[0005] Polymerization methods in the dental field are broadly divided into photopolymerization and chemical polymerization. Photopolymerization-type restorative materials, which use radically polymerizable monomers and photopolymerization initiators, undergo little polymerization reaction if kept in the dark. Therefore, all components can be manufactured and stored in the form of a single paste. This eliminates the need for the mixing and kneading process required for chemically polymerized restorative materials, and offers advantages such as a long usable life. For this reason, photopolymerization-type dental restorative materials have become mainstream in recent years. Hereinafter, such photopolymerization-type restorative materials will be referred to as dental photopolymerizable compositions.

[0006] When restoring tooth structure using the dental photopolymerizable composition, it is important that the color tone after restoration is the same as that of the surrounding tooth structure to achieve good aesthetics. However, when the polymerized and cured product of the dental photopolymerizable composition is exposed to ultraviolet light contained in sunlight, etc., it undergoes significant discoloration in a relatively short period of time. If the polymerized and cured product discolors, the color tone adjusted to the same color tone as the surrounding tooth structure during restoration is lost, resulting in a loss of the initial aesthetics and failure to satisfy the requirements for dental treatment. For example, JIS T 6514:2015 requires that the discoloration of the cured product be not easily detectable with the naked eye even after 10 hours of exposure to sunlight.

[0007] In order to prevent the cured product from discoloring due to ultraviolet rays contained in sunlight, etc., an ultraviolet absorber is blended into the dental photopolymerizable composition. Known examples of the ultraviolet absorber blended into the dental photopolymerizable composition include benzophenone-based ultraviolet absorbers, benzotriazole-based ultraviolet absorbers, and triazine-based ultraviolet absorbers, and among them, benzotriazole-based ultraviolet absorbers are known to have excellent sunlight stability (see, for example, Patent Documents 1 and 2).

[0008] JP 2004-231913 A JP 2006-117543 A JP 2016-166138 A

[0009] However, the ultraviolet absorbers of Patent Documents 1 to 3 have been found to have problems such as forming a quinoid structure or a complex with components such as a chemical polymerization initiator or a chemical polymerization accelerator contained in a dental curable composition during long-term storage, thereby causing coloration, or reacting with these components and affecting curability.

[0010] An object of the present invention is to provide a two-component dental composition that exhibits minimal color change and excellent color stability over the long term.

[0011] As a result of extensive research, the present inventors have found that the above-mentioned problems can be solved by a specific two-component dental composition comprising an ultraviolet absorber (A), a polymerizable monomer (B), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber having a maximum absorption wavelength in the wavelength band of 310 nm or more and 400 nm or less, and have thus completed the present invention.

[0012] That is, the present invention includes the following inventions: [1] A two-component dental composition comprising an ultraviolet absorber (A), a polymerizable monomer (B), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber having a maximum absorption wavelength in the wavelength band of 310 nm or more and 400 nm or less. [2] The two-component dental composition according to [1], wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber represented by the following general formula (1): (R 1 represents an alkyl group or an alkoxy group, and R 2 and R 3 are the same or different and each represents a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, or a halogen atom; R 4 , R 5 , and R 6 are the same or different and represent a hydrogen atom or an alkyl group; R 7 , and R 8 are the same or different and each represents a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, or a halogen atom; R 1 ~R 8 The alkyl group and alkoxy group of the formula (I) may have a substituent. [3] The two-component dental composition according to the above item [1] or [2], wherein the ultraviolet absorber (A) is present in an amount of 85 parts by mass or more per 100 parts by mass of the total of the ultraviolet absorbers. [4] The R of the ultraviolet absorber (A) 1 [5] The two-component dental composition according to [2] or [3], wherein R of the ultraviolet absorber (A) is an alkyl group or an alkoxy group having 1 to 15 carbon atoms. 1 [6] The two-component dental composition according to [4], wherein R is a branched alkyl group or an alkoxy group having 3 to 15 carbon atoms.1 is a 2-ethylhexyloxy group. [7] The two-component dental composition according to any one of [1] to [6], wherein the ultraviolet absorber (A) is bisethylhexyloxyphenol methoxyphenyl triazine and / or 2-[4,6-bis(biphenyl-4-yl)-1,3,5-triazin-2-yl]-5-[(2-ethylhexyl)oxy]phenol. [8] The two-component dental composition according to any one of [1] to [7], wherein the chemical polymerization initiator (C) is a peroxide. [9] The two-component dental composition according to any one of [1] to [8], wherein the chemical polymerization accelerator (D) is at least one selected from the group consisting of aromatic sulfinic acids and salts thereof, sulfur-containing reducing inorganic compounds, thiourea compounds, ascorbic acid compounds, benzotriazole compounds, benzimidazole compounds, and transition metal compounds.

[10] The two-component dental composition according to any one of [1] to [9], further comprising a photopolymerization initiator (E).

[11] The two-component dental composition according to any one of [1] to

[10] , further comprising a filler (F).

[0013] The two-component dental composition of the present invention exhibits minimal color change and excellent long-term color stability. Furthermore, because dental materials may be exposed to high temperatures during transportation and because there has been a recent demand for products that do not require refrigeration, the two-component dental composition of the present invention also exhibits excellent color stability at high temperatures. Furthermore, the two-component dental composition of the present invention produces little unpolymerized layer upon curing.

[0014] The two-component dental composition of the present invention comprises an ultraviolet absorber (A), a polymerizable monomer (B), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber having a maximum absorption wavelength in the wavelength band of 310 nm or more and 400 nm or less.

[0015] In this specification, the term "(meth)acrylic" is a general term for methacrylic and acrylic. Furthermore, in this specification, with regard to the content of each component, "100 parts by mass in total" means the total mass of the corresponding component contained in the two parts.

[0016] [Ultraviolet absorber (A)] The ultraviolet absorber (A) used in the two-component dental composition of the present invention is a triazine-based ultraviolet absorber having a maximum absorption wavelength in the wavelength range of 310 nm to 400 nm. The method for measuring the maximum absorption wavelength is as described in the Examples below.

[0017] The reason why the two-component dental composition of the present invention has excellent long-term color stability is presumed to be as follows: The triazine-based UV absorber (A) used in the present invention is less likely to form a quinoid structure or complex than conventional UV absorbers, even when a chemical polymerization initiator, a chemical polymerization accelerator, or the like is coexisting in the two-component dental composition, due to the structure of the compound, such as the phenyl group acting as a steric hindrance. Furthermore, the triazine-based UV absorber (A) itself has a maximum absorption wavelength in the wavelength range of 310 nm to 400 nm, so the peak wavelength does not shift significantly toward the long wavelength side of the light absorption spectrum, thereby suppressing color change. Furthermore, when the triazine-based UV absorber (A) coordinates as a ligand to a catalyst metal during long-term storage, the peak wavelength does not shift significantly toward the long wavelength side of the light absorption spectrum, thereby suppressing color change. Therefore, discoloration and effects on curability are suppressed over the long term compared to when other UV absorbers are used. In addition, the triazine-based ultraviolet absorber (A) used in the present invention is very stable against heat, and is therefore considered to have excellent color stability over the long term.

[0018] The ultraviolet absorber (A) is preferably a triazine ultraviolet absorber represented by the following general formula (1), in view of its superior long-term color stability. (R 1 represents an alkyl group or an alkoxy group, and R 2 , and R 3 are the same or different and each represents a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, or a halogen atom; R 4 , R 5 , and R 6 are the same or different and represent a hydrogen atom or an alkyl group; R 7 , and R 8are the same or different and each represents a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, or a halogen atom; R 1 ~R 8 The alkyl group and alkoxy group may have a substituent.

[0019] R 1 ~R 8 The alkyl group represented by the formula (I) may be linear, branched, or cyclic. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a cyclopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclobutyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, an n-hexyl group, an isohexyl group, a cyclohexyl group, an n-heptyl group, a cycloheptanyl group, an n-octyl group, a 2-ethylhexyl group, a cyclooctyl group, an n-nonyl group, a cyclononyl group, and an n-decyl group. The number of carbon atoms in the alkyl group is preferably 1 to 15, more preferably 1 to 12, even more preferably 1 to 10, and particularly preferably 1 to 8. The branched and cyclic alkyl groups preferably have 3 to 15 carbon atoms, more preferably 3 to 12 carbon atoms, even more preferably 3 to 10 carbon atoms, and particularly preferably 3 to 8 carbon atoms.

[0020] R 1 Regarding (a), in terms of superior long-term color stability, it is preferably an alkyl group or alkoxy group having 1 to 15 carbon atoms, more preferably a branched alkyl group or alkoxy group having 3 to 15 carbon atoms, and even more preferably a 2-ethylhexyloxy group.

[0021] R 1 ~R 3 , and R 7 ~R 8 The alkoxy group represented by the formula (I) may be linear, branched, or cyclic. 1 ~R 3 , and R 7 ~R 8The alkoxy group represented by the formula (I) is preferably branched. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a tert-butoxy group, an n-hexyloxy group, a cyclohexyloxy group, an n-octyloxy group, and a 2-ethylhexyloxy group. The number of carbon atoms in the alkoxy group is preferably 1 to 15, more preferably 1 to 12, even more preferably 1 to 10, and particularly preferably 1 to 8. The number of carbon atoms in the branched and cyclic alkoxy groups is preferably 3 to 15, more preferably 3 to 12, even more preferably 3 to 10, and particularly preferably 3 to 8.

[0022] R 7 , and R 8 Examples of the aryl group represented by the formula (I) include a phenyl group, a naphthyl group, an anthryl group, etc. The number of carbon atoms in the aryl group is preferably 6 to 14, and more preferably 6 to 10.

[0023] R 2 ~R 3 , and R 7 ~R 8 Examples of the halogen atom represented by the formula (I) include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0024] R 1 ~R 8 The alkyl group and alkoxy group in R may have a substituent. Examples of the substituent include a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, a dialkylamino group having an alkyl group having 1 to 6 carbon atoms, an amino group, etc. 1 ~R 8 The alkyl group and alkoxy group may be unsubstituted.

[0025] As the ultraviolet absorber (A), from the viewpoints of curability, initial color stability, and long-term color stability, it is preferable to use a triazine ultraviolet absorber represented by the above general formula (1) that has a maximum absorption wavelength in the wavelength region of 310 nm or more and 400 nm or less.

[0026] Furthermore, the range of the wavelength band in which the ultraviolet absorber (A) has a maximum absorption wavelength is preferably 390 nm or less, more preferably 385 nm or less, even more preferably 380 nm or less, and particularly preferably 375 nm or less, from the viewpoint that when the ultraviolet absorber (A) is coordinated as a ligand to a catalyst metal during long-term storage, the peak wavelength does not shift significantly to the long-wavelength side of the light absorption spectrum and change in color tone can be more easily suppressed.

[0027] Specific examples of the ultraviolet absorber (A) include 2,4,6-tris[4-(hexyloxy)-2-hydroxy-3-methylphenyl]-1,3,5-triazine, 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine, 2,4,6-tris(2,4-dihydroxyphenyl)-1,3,5-triazine, bisethylhexyloxyphenol methoxyphenyl triazine, 2-[4,6-bis(biphenyl-4-yl)-1,3,5-triazin-2-yl]-5-[(2-ethylhexyl)oxy]phenol, and the like, and bisethylhexyloxyphenol methoxyphenyl triazine and / or 2-[4,6-bis(biphenyl-4-yl)-1,3,5-triazin-2-yl]-5-[(2-ethylhexyl)oxy]phenol are preferred. The ultraviolet absorber (A) may be used alone or in combination of two or more kinds.

[0028] In view of the structural characteristics of the triazine-based ultraviolet absorber (A) (e.g., steric hindrance due to the phenyl group) and the fact that the triazine-based ultraviolet absorber (A) compound itself has an absorption maximum wavelength in the wavelength range of 310 nm to 400 nm, which enhances the effect of long-term color stability, the content of the ultraviolet absorber (A) is preferably 85 parts by mass or more, more preferably 90 parts by mass or more, even more preferably 95 parts by mass or more, even more preferably 98 parts by mass or more, and particularly preferably 100 parts by mass, per 100 parts by mass of the ultraviolet absorbers contained in the two-component dental composition of the present invention. When calculating the total 100 parts by mass of the ultraviolet absorbers contained in the two-component dental composition, the benzotriazole compound represented by general formula (2) and the benzimidazole compound represented by general formula (3) described below are not counted as ultraviolet absorbers.

[0029] From the viewpoints of curability, initial color stability, and long-term color stability, the content of the ultraviolet absorber (A) is preferably 0.0001% by mass or more, more preferably 0.001% by mass or more, even more preferably 0.005% by mass or more, and particularly preferably 0.01% by mass or more, relative to the total mass (100% by mass) of the two-component dental composition of the present invention. Also, from the viewpoints of curability, initial color stability, and long-term color stability, the content of the ultraviolet absorber (A) is preferably 1% by mass or less, more preferably 0.8% by mass or less, even more preferably 0.5% by mass or less, and particularly preferably 0.2% by mass or less, relative to the total mass (100% by mass) of the two-component dental composition of the present invention.

[0030] From the viewpoints of curability, initial color stability, and long-term color stability, the content of the ultraviolet absorber (A) is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass or more, even more preferably 0.05 parts by mass or more, and particularly preferably 0.1 parts by mass or more, relative to 100 parts by mass of the total of the polymerizable monomers (B). Also, from the viewpoints of curability, initial color stability, and long-term color stability, the content of the ultraviolet absorber (A) is preferably 5 parts by mass or less, more preferably 1 part by mass or less, even more preferably 0.8 parts by mass or less, and particularly preferably 0.5 parts by mass or less, relative to 100 parts by mass of the total of the polymerizable monomers (B).

[0031] [Polymerizable Monomer (B)] A radically polymerizable monomer is preferably used as the polymerizable monomer (B) used in the two-part dental composition of the present invention. Examples of the radically polymerizable monomer in the polymerizable monomer (B) include (meth)acrylate-based polymerizable monomers, (meth)acrylamide-based polymerizable 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 polymerizable monomers and (meth)acrylamide-based polymerizable monomers are preferred from the viewpoint of curability.

[0032] The polymerizable monomer (B) is roughly classified into a polymerizable monomer (B-1) having an acidic group and a polymerizable monomer (B-2) not having an acidic group. The polymerizable monomer (B) may be used alone or in combination of two or more kinds.

[0033] <Polymerizable Monomer (B-1) Having an Acidic Group> The two-component dental composition of the present invention may contain a polymerizable monomer (B-1) having an acidic group. The polymerizable monomer (B-1) having an acidic group used in the present invention is preferably a radically polymerizable monomer having at least one acidic group and a polymerizable group. From the viewpoint of adhesiveness, the acidic group is preferably a phosphate group, a pyrophosphate group, a thiophosphate group, a phosphonate group, a carboxylic acid group, a sulfonic acid group, or the like. Furthermore, from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The polymerizable monomer (B-1) having an acidic group may be blended alone or in combination of two or more types.

[0034] Examples of the polymerizable monomer having a phosphoric acid 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)acryloyloxyethyl dihydrogen phosphate, 9-(meth)acryloyloxypropyl dihydrogen phosphate, 10-(meth)acryloyloxybutyl dihydrogen phosphate, 11-(meth)acryloyloxybutyl dihydrogen phosphate, 12-(meth)acryloyloxybutyl dihydrogen phosphate, 13-(meth)acryloyloxybutyl 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)acryloyloxybutyl dihydrogen phosphate, 21-(meth)acryloyloxybutyl dihydrogen phosphate, 22-(meth)acryloyloxybutyl dihydrogen phosphate, 23-(meth)acryloyloxybutyl dihydrogen phosphate, 24-(meth)acryloyloxybutyl dihydrogen phosphate, 25-(meth)acryloyloxybutyl dihydrogen phosphate, 26-(meth)acryloyloxyhexyl dihydrogen phosphate, 27-(meth)acryloyloxyhexyl dihydrogen phosphate, 2 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 ester, bis[2-(meth)acryloyloxyethyl]hydrogenphosphate, bis[4-(meth)acryloyloxybutyl]hydrogenphosphate, bis[6-(meth)acryloyloxyhexyl]hydrogenphosphate, bis[8-(meth)acryloyloxyoctyl]hydrogenphosphate, bis[9-(meth)acryloyloxynonyl]hydrogenphosphate, bis[10-(meth)acryloyloxydecyl]hydrogenphosphate, 1,3-di(meth)acryloyloxyethyl]hydrogenphosphate, Examples include acryloyloxypropyl dihydrogen phosphate, 2-(meth)acryloyloxyethyl phenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogen phosphate, 2-(meth)acryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, 2-(meth)acryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, and acid chlorides, alkali metal salts and amine salts thereof.

[0035] Examples of the polymerizable 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.

[0036] Examples of the polymerizable 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, and 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate. 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.

[0037] Examples of the polymerizable 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 phosphonoacetate, 10-(meth)acryloyloxydecyl-3-phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0038] Examples of the polymerizable monomer having a carboxylic acid group include monofunctional (meth)acrylic acid esters having one carboxyl group or an acid anhydride group thereof in the molecule, monofunctional (meth)acrylic acid esters having multiple carboxyl groups or acid anhydride groups thereof in the molecule, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0039] Examples of the monofunctional polymerizable monomer having one carboxyl group or an acid anhydride group thereof in the 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, N-(meth)acryloyltyrosine, Examples of the acryloyloxybenzoic acid include 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, and N-(meth)acryloyl-4-aminosalicylic acid, as well as compounds in which the carboxyl group of these compounds has been converted to an acid anhydride group.

[0040] Examples of monofunctional polymerizable monomers having a plurality of carboxyl groups or acid anhydride groups thereof in the 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 ... butyl trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethylnaphthalene-1,2,6-tricarboxylic anhydride, 6-(meth)acryloyloxyethylnaphthalene-2,3,6-tricarboxylic anhydride, 4-(meth)acryloyloxyethylcarbonylpropionoyl-1,8-naphthalic anhydride, 4-(meth)acryloyloxyethylnaphthalene-1,8-tricarboxylic anhydride, and the like.

[0041] Examples of the polymerizable monomer having a sulfonic acid group include 2-sulfoethyl (meth)acrylate and its acid chlorides, alkali metal salts, and ammonium salts.

[0042] Among these polymerizable monomers (B-1) having an acidic group, from the viewpoint of good adhesive strength when used in a two-component dental composition, polymerizable monomers having a phosphate group or polymerizable monomers having a carboxylic acid group are preferred, 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)acryloyloxy thioctyl 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-(meth)acryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, with 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 being even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being the most preferred from the viewpoint of a balance of curability.

[0043] Furthermore, from the viewpoint of adhesion to tooth structure, the content of the polymerizable monomer (B-1) having an acidic group in the two-component dental composition of the present invention is preferably 0 to 30 parts by mass, more preferably 0 to 20 parts by mass, and even more preferably 0 to 15 parts by mass, per 100 parts by mass of the total polymerizable monomer (B).

[0044] <Polymerizable Monomer (B-2) Not Having an Acidic Group> The polymerizable monomer (B-2) not having an acidic group in the present invention can be divided into hydrophilic polymerizable monomers (B-2a) not having an acidic group, which have a solubility of 4.5 g / L or more in water at 25° C., and hydrophobic polymerizable monomers (B-2b) not having an acidic group, which have a solubility of less than 4.5 g / L in water at 25° C. The polymerizable monomer (B-2) not having an acidic group may be used alone or in combination of two or more.

[0045] Hydrophilic Polymerizable Monomer (B-2a) Having No Acidic Group In the two-component dental composition of the present invention, the content of the hydrophilic polymerizable monomer (B-2a) having no acidic group (hereinafter, sometimes simply referred to as "hydrophilic polymerizable monomer (B-2a)") is preferably less than 15 parts by mass per 100 parts by mass of the total polymerizable monomer (B). The hydrophilic polymerizable monomer (B-2a) refers to a monomer that does not have an acidic group and has a solubility in water at 25°C of 4.5 g / L or more. In the two-component dental composition of the present invention, in order to achieve both paste fluidity and formability, the content of the monomer defined by the solubility in water is preferably less than 15 parts by mass per 100 parts by mass of the total polymerizable monomer (B). One type of hydrophilic polymerizable monomer (B-2a) may be used alone, or two or more types may be used in combination.

[0046] If the content of the hydrophilic polymerizable monomer (B-2a) in the two-component dental composition of the present invention is 15 parts by mass or more per 100 parts by mass of the total polymerizable monomers (B), the fluidity of the paste will decrease and it will no longer be possible to achieve both formability and durability. Therefore, the content of the hydrophilic polymerizable monomer (B-2a) in the two-component dental composition of the present invention is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, per 100 parts by mass of the total polymerizable monomers (B). Furthermore, the content of the hydrophilic polymerizable monomer (B-2a) may be 0 parts by mass per 100 parts by mass of the total polymerizable monomers (B).

[0047] The hydrophilic polymerizable monomer (B-2a) improves the wettability of the two-component dental composition to tooth structure. As the hydrophilic polymerizable monomer (B-2a), a radical polymerizable monomer having no acidic group but a polymerizable group is preferred, and from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. Examples of the hydrophilic polymerizable monomer (B-2a) include hydrophilic (meth)acrylate-based monofunctional polymerizable monomers such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,3-dihydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 2-((meth)acryloyloxy)ethyltrimethylammonium chloride, and tetrahydrofurfuryl (meth)acrylate; triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, nonaethylene glycol di(meth)acrylate, 1,3-bis(methacryloyloxy)-2-propanol, 1,2 and hydrophilic (meth)acrylate-based polyfunctional polymerizable monomers such as N-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane; and hydrophilic (meth)acrylamide-based polymerizable monomers such as N-methylol(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N,N-bis(2-hydroxyethyl)(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-ethoxymethyl(meth)acrylamide, diacetone(meth)acrylamide, 4-(meth)acryloylmorpholine, N-trihydroxymethyl-N-methyl(meth)acrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, and N-methacryloyloxyethylacrylamide.

[0048] Among these hydrophilic polymerizable monomers (B-2a), it is preferable to use a (meth)acrylate-based polyfunctional polymerizable monomer from the viewpoint of curability. Among them, triethylene glycol dimethacrylate (commonly known as "3G"), 1,3-bis(methacryloyloxy)-2-propanol, and 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane (commonly known as "#801") are more preferable, and 3G and #801 are even more preferable.

[0049] Hydrophobic Polymerizable Monomer (B-2b) Having No Acidic Group In the two-component dental composition of the present invention, the polymerizable monomer (B) includes a hydrophobic polymerizable monomer (B-2b) having no acidic group (hereinafter, sometimes simply referred to as "hydrophobic polymerizable monomer (B-2b)"). Here, the hydrophobic polymerizable monomer (B-2b) refers to a monomer that does not have an acidic group and has a solubility in water at 25°C of less than 4.5 g / L. The use of the hydrophobic polymerizable monomer (B-2b) weakens the hydrophilic interaction between the polymerizable monomer and the filler (F) when combined with the filler (F), thereby improving the fluidity of the paste. Furthermore, the hydrophobic polymerizable monomer (B-2b) can suppress the stringiness (ease of stringing) of the two-component dental composition and improve the mechanical strength of the cured product. The hydrophobic polymerizable monomer (B-2b) may be used alone or in combination of two or more.

[0050] The hydrophobic polymerizable monomer (B-2b) is preferably a radically polymerizable monomer having a polymerizable group but no acidic group, and from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. Examples of the hydrophobic polymerizable monomer (B-2b) include, in addition to hydrophobic monofunctional polymerizable monomers, crosslinkable polymerizable monomers such as hydrophobic aromatic compound-based bifunctional polymerizable monomers, hydrophobic aliphatic compound-based bifunctional polymerizable monomers, and hydrophobic trifunctional or higher functional polymerizable monomers.

[0051] Examples of hydrophobic monofunctional polymerizable monomers include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, benzyl (meth)acrylate, isobornyl (meth)acrylate, p-cumyl-phenoxyethylene glycol (meth)acrylate, m-phenoxybenzyl (meth)acrylate, stearyl (meth)acrylate, dicyclopentanyl (meth)acrylate, butoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, etc. Among these, benzyl methacrylate, isobornyl methacrylate, and p-cumyl-phenoxyethylene glycol methacrylate are preferred.

[0052] Examples of hydrophobic aromatic compound-based bifunctional polymerizable monomers include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(2-hydroxy-3-(meth)acryloyloxypropoxy)phenyl]propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane. 2-(4-(meth)acryloyloxydipropoxyphenyl)propane, 2,2-bis(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, and the like. Among these, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-methacryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6, commonly known as "D-2.6E"), 2,2-bis(4-methacryloyloxydiethoxyphenyl)propane, 2,2-bis(4-methacryloyloxytriethoxyphenyl)propane, 2,2-bis(4-methacryloyloxytetraethoxyphenyl)propane, and 2,2-bis(4-methacryloyloxypentaethoxyphenyl)propane are preferred, and Bis-GMA and D-2.6E are more preferred.

[0053] Examples of the aliphatic compound-based bifunctional polymerizable monomer include monoethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, and 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)di(meth)acrylate. Among these, neopentyl glycol dimethacrylate (commonly known as "NPG"), 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (commonly known as "UDMA"), 1,10-decanediol dimethacrylate (commonly known as "DD"), and 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate are preferred, with NPG, UDMA, and DD being more preferred.

[0054] Examples of trifunctional or higher functional polymerizable monomers include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetra(meth)acrylate, and 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane. Of these, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate is preferred.

[0055] Among these hydrophobic polymerizable monomers (B-2b), aromatic compound-based bifunctional polymerizable monomers and aliphatic compound-based bifunctional polymerizable monomers are preferred from the viewpoints of handling properties and mechanical strength of the cured product.

[0056] Furthermore, if the content of the hydrophobic polymerizable monomer (B-2b) in the two-component dental composition of the present invention is excessive, the wettability of the two-component dental composition to tooth tissue may decrease, resulting in decreased adhesion, whereas if the content is too low, the hydrophilic interaction between the polymerizable monomer and the filler may be strong, resulting in insufficient paste fluidity and insufficient mechanical strength of the cured product. Therefore, the content of the hydrophobic polymerizable monomer (B-2b) in the two-component dental composition of the present invention is preferably 55 parts by mass or more, more preferably 65 parts by mass or more, even more preferably 70 parts by mass or more, even more preferably 85 parts by mass or more, particularly preferably 90 parts by mass or more, and may even be 100 parts by mass, per 100 parts by mass of the total polymerizable monomer (B).

[0057] [Chemical Polymerization Initiator (C)] The two-component dental composition of the present invention contains a chemical polymerization initiator (C).

[0058] Examples of the chemical polymerization initiator (C) include peroxides (organic peroxides and inorganic peroxides). These are not particularly limited and known peroxides can be used. The chemical polymerization initiator (C) may be used alone or in combination of two or more.

[0059] Representative organic peroxides include hydroperoxides, peroxyesters, ketone peroxides, peroxyketals, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, etc. Among these, hydroperoxides and peroxyesters are particularly preferred, and peroxyesters are most preferred because they show little change in the operable time even when the two-component dental composition of the present invention is stored for a long period of time.

[0060] More specifically, examples of the hydroperoxide include cumene hydroperoxide, t-butyl hydroperoxide, t-hexyl hydroperoxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide (hereinafter sometimes abbreviated as "THP").

[0061] Any known peroxyester can be used without any restrictions as long as it has an acyl group on one side of a peroxy group (-OO- group) and a hydrocarbon group (or a group similar thereto) on the other side. Specific examples include α,α-bis(neodecanoylperoxy)diisopropylbenzene, cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxy neodecanoate, t-hexyl peroxy neodecanoate, t-butyl peroxy neodecanoate, t-hexyl peroxy pivalate, t-butyl peroxy pivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, t- Examples of peroxybenzoates include butyl peroxyisobutyrate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxylaurate, 2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, t-hexylperoxybenzoate, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butylperoxyacetate, t-butylperoxy-m-toluoylbenzoate, t-butylperoxybenzoate (hereinafter sometimes abbreviated as "BPB"), and bis(t-butylperoxy)isophthalate. Among these, from the viewpoints of storage stability and reactivity, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, and t-butylperoxyacetate are preferred, and t-butylperoxybenzoate is more preferred.

[0062] Examples of ketone peroxides include methyl ethyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, methylacetoacetate peroxide, and acetylacetone peroxide.

[0063] Examples of peroxyketals include 1,1-bis(t-hexylperoxy)3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexanone, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)cyclodecane, 2,2-bis(t-butylperoxy)butane, n-butyl 4,4-bis(t-butylperoxy)valerate, and 2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane.

[0064] Examples of dialkyl peroxides include α,α-bis(t-butylperoxy)diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-bis(t-butylperoxy)3-hexyne.

[0065] Examples of diacyl peroxides include isobutyryl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearyl peroxide, succinic acid peroxide, m-toluoylbenzoyl peroxide, and benzoyl peroxide.

[0066] Examples of peroxydicarbonates include di-n-propyl peroxydicarbonate, diisopropyl peroxydicarbonate, bis(4-t-butylcyclohexyl)peroxydicarbonate, di(2-ethoxyethyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, di(2-methoxybutyl)peroxydicarbonate, and di(3-methyl-3-methoxybutyl)peroxydicarbonate.

[0067] Examples of inorganic peroxides include peroxodisulfates and peroxodiphosphates, and among these, peroxodisulfates are preferred in terms of curability. Specific examples of peroxodisulfates include sodium peroxodisulfate, potassium peroxodisulfate (hereinafter sometimes abbreviated as "KPS"), aluminum peroxodisulfate, and ammonium peroxodisulfate.

[0068] From the viewpoint of curability, the content of the organic peroxide and the inorganic peroxide is preferably 0.01 to 5 parts by mass, and more preferably 0.05 to 2 parts by mass, per 100 parts by mass of the total of the polymerizable monomer (B) in the two-component dental composition of the present invention.

[0069] [Chemical Polymerization Accelerator (D)] The chemical polymerization accelerator (D) used in the two-component dental composition of the present invention includes aliphatic amines, aromatic amines having no electron-withdrawing group on the aromatic ring, transition metal compounds (fourth-period transition metal compounds, transition metal compounds other than the fourth-period transition metal compounds), thiourea compounds, tin compounds, aromatic sulfinic acids and their salts, benzotriazole compounds, benzimidazole compounds, bromides, borate compounds, barbituric acid compounds, ascorbic acid compounds, and sulfur-containing reducing inorganic compounds. Preferably, the chemical polymerization accelerator (D) is at least one selected from the group consisting of aromatic sulfinic acids and their salts, sulfur-containing reducing inorganic compounds, thiourea compounds, ascorbic acid compounds, benzotriazole compounds, benzimidazole compounds, and transition metal compounds. One type of chemical polymerization accelerator (D) may be used alone, or two or more types may be used in combination.

[0070] In one embodiment, when the polymerizable monomer (B) does not contain a polymerizable monomer (B-1) having an acidic group, the chemical polymerization accelerator (D) is preferably at least one selected from the group consisting of aromatic amines having no electron-withdrawing group on the aromatic ring, fourth-period transition metal compounds, transition metal compounds other than the fourth-period transition metal compounds, and thiourea compounds. In the above embodiment, the content of the chemical polymerization accelerator (D) is preferably 0.001 to 20 parts by mass, more preferably 0.005 to 10 parts by mass, and even more preferably 0.025 to 5 parts by mass, per 100 parts by mass of the total polymerizable monomers (B), from the viewpoints of curability and storage stability. In another embodiment, when the polymerizable monomer (B) contains a polymerizable monomer (B-1) having an acidic group, the chemical polymerization accelerator (D) is preferably at least one selected from the group consisting of copper compounds, aromatic sulfinic acids and salts thereof, benzotriazole compounds, benzimidazole compounds, bromides, ascorbic acid compounds, and sulfur-containing reducing inorganic compounds. In the above embodiment, the content of the chemical polymerization accelerator (D) is preferably 0.001 to 40 parts by mass, more preferably 0.005 to 20 parts by mass, and even more preferably 0.025 to 10 parts by mass, relative to 100 parts by mass of the total of the polymerizable monomers (B), from the viewpoints of curability and storage stability.

[0071] Examples of aliphatic amines include primary aliphatic amines such as n-butylamine, n-hexylamine, and n-octylamine; secondary aliphatic amines such as diisopropylamine, dibutylamine, and N-methylethanolamine; and tertiary aliphatic amines such as N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl(meth)acrylate, N-methyldiethanolamine di(meth)acrylate, N-ethyldiethanolamine di(meth)acrylate, triethanolamine tri(meth)acrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, tertiary aliphatic amines are preferred in terms of redox reactivity, and N-methyldiethanolamine, triethanolamine, and 2-(dimethylamino)ethyl methacrylate are particularly preferred.

[0072] Examples of aromatic amines that do not have an electron-withdrawing group in the aromatic ring include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine (hereinafter sometimes abbreviated as "DEPT"), 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, and N,N-bis(2-hydroxyethyl)-3,5-di- Examples of aromatic tertiary amines include isopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, 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, and N,N-dimethyl-3,5-di-t-butylaniline. Aromatic amines that do not have an electron-withdrawing group on the aromatic ring are used as reducing agents for redox polymerization initiators. Among these, N,N-bis(2-hydroxyethyl)-p-toluidine is preferred in terms of redox reactivity.

[0073] The fourth period transition metal compound may be any of a vanadium compound, a copper compound, and a fourth period transition metal compound other than vanadium and copper (hereinafter, simply referred to as "other fourth period transition metal compounds"). In an embodiment, the chemical polymerization accelerator (D) preferably contains a vanadium compound and a copper compound from the viewpoint of the polymerization acceleration effect.

[0074] Examples of vanadium compounds include vanadyl acetylacetonate(IV), vanadyl stearate, vanadium naphthenate, vanadium benzoylacetonate, vanadyl oxalate, bis(maltolate)oxovanadium(IV), oxobis(1-phenyl-1,3-butanedionato)vanadium(IV), vanadium(V) oxytriisopropoxide, ammonium metavanadate(V), sodium metavanadate(V), vanadium pentoxide, divanadium(IV) tetroxide, and vanadyl(IV) sulfate. Among these, vanadyl acetylacetonate(IV) and bis(maltolate)oxovanadium(IV) are preferred, with vanadyl acetylacetonate(IV) being more preferred, from the viewpoint of solubility in solvents.

[0075] From the viewpoint of hardening property, the content of the vanadium compound is preferably 0.005 to 1 part by mass per 100 parts by mass of the total of the polymerizable monomers (B) in the two-component dental composition of the present invention.

[0076] Examples of copper compounds are preferably compounds soluble in radically polymerizable monomers. Examples of copper compounds include copper carboxylate, copper β-diketone, copper β-ketoester, copper alkoxide, copper dithiocarbamate, and salts of copper and inorganic acids. Examples of copper carboxylates include copper acetate, copper isobutyrate, copper gluconate, copper citrate, copper phthalate, copper tartrate, copper oleate, copper octylate, copper octenoate, copper naphthenate, copper methacrylate, and copper 4-cyclohexylbutyrate. Examples of copper β-diketones include copper acetylacetone, copper trifluoroacetylacetone, copper hexafluoroacetylacetone, copper 2,2,6,6-tetramethyl-3,5-heptanedionato, and copper benzoylacetone. Examples of copper β-ketoesters include copper acetoacetate. Examples of copper alkoxides include copper methoxide, copper ethoxide, copper isopropoxide, copper 2-(2-butoxyethoxy)ethoxide, and copper 2-(2-methoxyethoxy)ethoxide. Examples of copper dithiocarbamates include copper dimethyldithiocarbamate. Examples of salts of copper with inorganic acids include copper nitrate and copper chloride. Among these, from the viewpoints of solubility and reactivity with the polymerizable monomer (B), copper carboxylate, β-diketone copper, and β-ketoester copper are preferred, and copper acetate and copper acetylacetonate are more preferred.

[0077] From the viewpoint of hardening property, the content of the copper compound is preferably 0.000005 to 1 part by mass, more preferably 0.00001 to 0.5 parts by mass, and even more preferably 0.0001 to 0.1 parts by mass, per 100 parts by mass of the total of the polymerizable monomers (B) in the two-component dental composition of the present invention.

[0078] Other examples of fourth-row transition metal compounds include scandium isopropoxide, iron (III) ethoxide, titanium methoxide, titanium ethoxide, titanium isopropoxide, titanium butoxide, titanium hydroxide, and titanium fluoride.

[0079] Among the above-mentioned fourth period transition metal compounds, vanadyl acetylacetonate(IV) and bis(maltolato)oxovanadium(IV) are preferred, with vanadyl acetylacetonate(IV) being more preferred, from the viewpoint of their high polymerization-promoting effect.

[0080] Examples of transition metal compounds other than those of the fourth period include strontium carbonate, strontium hydroxide, strontium ethoxide, tin (II) methoxide, indium ethoxide, actinium ethoxide, yttrium isopropoxide, lanthanum methoxide, lanthanum ethoxide, lanthanum isopropoxide, lanthanum butoxide, lanthanum hydroxide, lanthanum carbonate, lanthanum fluoride, cerium isopropoxide, praseodymium isopropoxide, promethium isopropoxide, neodymium isopropoxide, and sulfur dioxide. Examples of the isopropoxide include marium isopropoxide, europium isopropoxide, gadolinium isopropoxide, terbium ethoxide, terbium methoxide, dysprosium isopropoxide, holmium isopropoxide, erbium isopropoxide, thulium isopropoxide, ytterbium isopropoxide, zirconium ethoxide, zirconium isopropoxide, zirconium butoxide, tungsten(IV) methoxide, tungsten(IV) isopropoxide, and tungsten(IV) butoxide.

[0081] Examples of the thiourea compound include thiourea, methylthiourea, ethylthiourea, ethylenethiourea, 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, tetracyclohexylthiourea, 1-(2-pyridyl)-2-thiourea, (6-methyl-pyridin-2-yl)thiourea, 4,4-dimethylethylenethiourea, etc. Among these, 1-(2-pyridyl)-2-thiourea, (6-methyl-pyridin-2-yl)thiourea, and 4,4-dimethylethylenethiourea are preferred from the viewpoints of solubility in solvents and storage stability.

[0082] Examples of tin compounds include di-n-butyltin dimaleate, di-n-octyltin dimaleate, di-n-octyltin dilaurate, di-n-butyltin dilaurate, etc. Particularly suitable tin compounds are di-n-octyltin dilaurate and di-n-butyltin dilaurate.

[0083] Examples of aromatic sulfinic acids and salts thereof include benzenesulfinic acid, p-toluenesulfinic acid, o-toluenesulfinic acid, ethylbenzenesulfinic acid, decylbenzenesulfinic acid, dodecylbenzenesulfinic acid, 2,4,6-trimethylbenzenesulfinic acid, 2,4,6-triisopropylbenzenesulfinic acid, chlorobenzenesulfinic acid, naphthalenesulfinic acid, and their lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, iron, zinc, ammonium, tetramethylammonium, and tetraethylammonium salts. Among these, from the viewpoint of the polymerizability and storage stability of the composition, the lithium, sodium, potassium, magnesium, and calcium salts of 2,4,6-trimethylbenzenesulfinic acid and 2,4,6-triisopropylbenzenesulfinic acid are preferred, and the lithium, sodium, potassium, magnesium, and calcium salts of 2,4,6-triisopropylbenzenesulfinic acid are more preferred.

[0084] Preferably, the aromatic sulfinic acid and its salt are at least partially dispersed in the composition in powder form. Dispersing the aromatic sulfinic acid and its salt in powder form allows the two-component dental composition of the present invention to ensure a longer operating time. Furthermore, when applied to a wet body such as a tooth, the aromatic sulfinic acid and its salt dissolve in water on the wet body surface, further enhancing polymerization at the adhesive interface and within the resin-impregnated layer. When the aromatic sulfinic acid and its salt are dispersed in powder form, the aromatic sulfinic acid and its salt preferably have a solubility in water at room temperature (25°C) of 1 mg / 100 mL or more. Having such a solubility of 1 mg / 100 mL or more facilitates sufficient dissolution of the aromatic sulfinic acid and its salt in water at the adhesive interface when the two-component dental composition of the present invention is applied to a wet body, thereby enhancing the effect of dispersion in powder form. Furthermore, since aromatic sulfinic acids and their salts are less likely to settle, the average particle size is preferably 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. Furthermore, from the viewpoint of preventing the specific surface area of ​​the powder from becoming excessively large and ensuring good handleability of the two-component dental composition, the average particle size is preferably 0.01 μm or more. That is, when dispersed as a powder, the average particle size is preferably in the range of 0.01 to 500 μm, more preferably 0.01 to 100 μm. The average particle size can be measured in the same manner as the average particle size of the filler (F) described below.

[0085] When aromatic sulfinic acid and its salts are dispersed in powder form, the shape thereof may be, but is not particularly limited to, various shapes such as spherical, needle-like, plate-like, crushed, etc. Aromatic sulfinic acid salts can be prepared into fine powder by conventionally known methods such as pulverization and freeze-drying.

[0086] From the viewpoints of working time and adhesiveness, the content of aromatic sulfinic acid and its salt is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 4 parts by mass, and even more preferably 0.5 to 3 parts by mass, relative to 100 parts by mass of the total of the polymerizable monomers (B) in the adhesive composition of the present invention. If the content is less than 0.1 part by mass, adhesiveness may decrease, and if it exceeds 5 parts by mass, working time may become shorter.

[0087] Examples of the benzotriazole compound and / or benzimidazole compound include compounds represented by the following general formula (2) and compounds represented by the following general formula (3). The benzotriazole compound and benzimidazole compound may be used alone or in combination of two or more. Benzotriazole compounds and benzimidazole compounds that do not have a substituent at the 2-position, such as the compounds represented by the following general formula (2) and the compounds represented by the following general formula (3), have an absorption peak at a position away from the visible light region (for example, 300 nm or less). Therefore, unlike benzotriazole compounds having a substituent at the 2-position (e.g., 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole (also referred to as "TN326")), these compounds have a small conjugation extent and do not significantly shift the peak wavelength to the long wavelength side of the light absorption spectrum. Furthermore, even when a catalytic metal (e.g., a copper compound) is present in the system, when these compounds coordinate to the catalytic metal as a ligand, even if a shift in the peak wavelength to the long wavelength side of the light absorption spectrum occurs due to charge transfer between the metal and the ligand, the shift is not significant, and the effect on discoloration can be suppressed. Therefore, when compound represented by the following general formula (2) and compound represented by the general formula (3) are blended as a chemical polymerization accelerator (D), they can promote chemical polymerization without impairing the effect of the ultraviolet absorber (A).

[0088]

[0089]

[0090] In the above general formulas (2) and (3), A1 to A8 each independently represent a hydrogen atom, a hydroxyl group, an alkyl group, an aryl group, an alkoxy group, an alkenyl group, an aralkyl group, or a halogen atom.

[0091] The alkyl groups represented by A1 to A8 may be linear, branched, or cyclic, and preferably have 1 to 10 carbon atoms (branched and cyclic alkyl groups have 3 to 10 carbon atoms). Specific examples of the alkyl group include methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, cyclobutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, n-hexyl, isohexyl, cyclohexyl, n-heptyl, cycloheptanyl, n-octyl, 2-ethylhexyl, cyclooctyl, n-nonyl, cyclononyl, and n-decyl. Of these, methyl and ethyl groups are particularly preferred.

[0092] The aryl groups represented by A1 to A8 preferably have 6 to 14 carbon atoms, and examples thereof include a phenyl group, a naphthyl group, and an anthryl group.

[0093] The alkoxy groups represented by A1 to A8 may be linear, branched, or cyclic, and preferably have a carbon number of 1 to 8. Specific examples include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a tert-butoxy group, an n-hexyloxy group, a cyclohexyloxy group, an n-octyloxy group, and a 2-ethylhexyloxy group.

[0094] The alkenyl groups represented by A1 to A8 may be linear, branched, or cyclic, and preferably have a carbon number of 1 to 6. Specific examples include a vinyl group, an allyl group, a methylvinyl group, a propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a cyclopropenyl group, a cyclobutenyl group, a cyclopentenyl group, and a cyclohexenyl group.

[0095] Examples of the aralkyl group represented by A1 to A8 include an alkyl group (particularly, an alkyl group having 1 to 10 carbon atoms) substituted with an aryl group (particularly, an aryl group having 6 to 10 carbon atoms), and specific examples include a benzyl group.

[0096] Examples of the halogen atom represented by A1 to A8 include a chlorine atom, a bromine atom, and an iodine atom.

[0097] A1 to A8 are preferably a hydrogen atom or a methyl group.

[0098] Specific examples of benzotriazole compounds and benzimidazole compounds include 1H-benzotriazole (hereinafter sometimes abbreviated as "BTA"), 5-methyl-1H-benzotriazole, 5,6-dimethyl-1H-benzotriazole, benzimidazole, 5-methylbenzimidazole, 5,6-dimethylbenzimidazole, etc. Among these, 1H-benzotriazole and 5-methyl-1H-benzotriazole are preferred in that they have a small conjugated system, can further suppress color change in the composition, do not change color even during long-term storage, and are particularly excellent in long-term color stability.

[0099] Examples of bromides include zinc bromide, potassium bromide, sodium bromide, calcium bromide, indium bromide, ammonium bromide, tetrabutylammonium bromide, etc. Among these, zinc bromide, ammonium bromide, and tetrabutylammonium bromide are particularly preferred.

[0100] Examples of borate compounds include arylborate compounds having 1 to 4 aryl groups in one molecule (e.g., tetraphenylboron, tetrakis(p-chlorophenyl)boron, etc.) and salts thereof. Examples of barbituric acid compounds include barbituric acid, 5-butylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and salts thereof.

[0101] Examples of ascorbic acid compounds include salts, esters, and ethers of ascorbic acid. Among these, salts and esters of ascorbic acid are preferred.

[0102] Examples of salts of ascorbic acid include sodium L-ascorbate, calcium L-ascorbate, potassium ascorbate, and stereoisomers thereof (e.g., sodium isoascorbate, etc.), etc. Among these, sodium L-ascorbate is preferred.

[0103] Esters of ascorbic acid include those formed by reacting one or more hydroxy groups of ascorbic acid with a carboxylic acid. Suitable examples of the carboxylic acid include fatty acids such as saturated or unsaturated fatty acids having 6 to 30 carbon atoms, such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linoleelaidic acid, α-linolenic acid, arachidonic acid, eicosapentaenoic acid, erucic acid, and docosahexaenoic acid. The number of carbon atoms in the fatty acid is preferably 10 to 28, more preferably 12 to 26, and even more preferably 14 to 24. Among these, esters of stearic acid and ascorbic acid, and esters of palmitic acid and ascorbic acid (ascorbyl palmitate) are particularly preferred.

[0104] Examples of the ethers of ascorbic acid include ethyl ascorbate and cetyl ascorbate.

[0105] Examples of reducing inorganic compounds containing sulfur include sulfites, bisulfites, pyrosulfites, thiosulfates, thionates, and dithionites, and among these, sulfites and bisulfites are preferred.Specific examples of reducing inorganic compounds containing sulfur include sodium sulfite, potassium sulfite, calcium sulfite, ammonium sulfite, sodium hydrogen sulfite, and potassium hydrogen sulfite.

[0106] Preferably, at least a portion of the sulfur-containing reducing inorganic compound is dispersed in the composition in powder form. Dispersing the sulfur-containing reducing inorganic compound in powder form allows the two-component dental composition of the present invention to have a longer operating time. Furthermore, when applied to a tooth, the sulfur-containing reducing inorganic compound dissolves in water on the tooth surface, further enhancing polymerization at the adhesive interface and within the resin-impregnated layer. When the sulfur-containing reducing inorganic compound is dispersed in powder form, the sulfur-containing reducing inorganic compound preferably has a solubility in water at room temperature (25°C) of 1 mg / 100 mL or more. Having a solubility of 1 mg / 100 mL or more allows the sulfur-containing reducing inorganic compound to dissolve sufficiently in water at the adhesive interface when the two-component dental composition of the present invention is applied to a tooth, thereby facilitating the powder dispersion effect. Furthermore, the sulfur-containing reducing inorganic compound preferably has an average particle size of 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less, in order to reduce sedimentation. Furthermore, from the viewpoint of preventing the specific surface area of ​​the powder from becoming too large and facilitating the easy handling of the two-component dental composition, the average particle size is preferably 0.01 μm or more. That is, when dispersed as a powder, the average particle size is preferably in the range of 0.01 to 500 μm, more preferably in the range of 0.01 to 100 μm. The average particle size can be measured in the same manner as the average particle size of the filler (F) described below.

[0107] When the sulfur-containing reducing inorganic compound is dispersed in the form of a powder, the shape of the powder may be, but is not particularly limited to, various shapes such as spherical, needle-like, plate-like, crushed, etc. The sulfur-containing reducing inorganic compound can be prepared into a fine powder by a conventionally known method such as a pulverization method or a freeze-drying method.

[0108] [Photopolymerization initiator (E)] In order to make the two-component dental composition of the present invention a dual-cure type in which polymerization is also initiated by light irradiation, a conventionally known photopolymerization initiator (E) may be further contained in addition to the chemical polymerization initiator (C). A preferred embodiment includes a two-component dental composition further comprising a photopolymerization initiator (E) in at least one of the first and second components. Another preferred embodiment includes a two-component dental composition further comprising a photopolymerization initiator (E) in both the first and second components. The photopolymerization initiator (E) may be blended in the same component as the ultraviolet absorber (A), or may be blended separately from the ultraviolet absorber (A).

[0109] There are no particular limitations on the type of photopolymerization initiator (E), and conventionally known photopolymerization initiators can be used without any limitations. Examples of conventionally known photopolymerization initiators include α-diketones, ketals, thioxanthones, (bis)acylphosphine oxides, α-aminoacetophenones, and amines. One type of photopolymerization initiator (E) may be used alone, or two or more types may be used in combination.

[0110] Examples of α-diketones include dl-camphorquinone (commonly known as "CQ"), benzil, and 2,3-pentanedione.

[0111] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0112] The thioxanthones include 2-chlorothioxanthone and 2,4-diethylthioxanthone.

[0113] Examples of the (bis)acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, dibenzoylphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, tris(2,4-dimethylbenzoyl)phosphine oxide, tris(2-methoxybenzoyl)phosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, benzoyl-bis(2,6-dimethylphenyl)phosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, and the water-soluble acylphosphine oxide compounds disclosed in JP-B-3-57916.

[0114] Examples of α-aminoacetophenones include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-butanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-propanone, 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-pentanone, and 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-pentanone.

[0115] Examples of amines include aromatic amines. Examples of aromatic amines include aromatic amines other than the aromatic amines used as the chemical polymerization accelerator (D) that do not have an electron-withdrawing group on the aromatic ring. Examples of such aromatic amines include tertiary aromatic amines having an electron-withdrawing group on the aromatic ring, such as n-butoxyethyl 4-(N,N-dimethylamino)benzoate, (2-methacryloyloxy)ethyl 4-(N,N-dimethylamino)benzoate, ethyl 4-(N,N-dimethylamino)benzoate, butyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone. Among these, at least one selected from the group consisting of ethyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone is preferred from the viewpoint of imparting excellent curability to the two-part dental composition.

[0116] Among these, from the viewpoint of curability and the like, the photopolymerization initiator (E) is preferably an α-diketone or an acylphosphine oxide, more preferably an α-diketone, and even more preferably dl-camphorquinone.

[0117] From the viewpoints of curability and storage stability, the content of the photopolymerization initiator (E) is preferably 0.005 to 10 parts by mass, more preferably 0.01 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the total of the polymerizable monomers (B).

[0118] [Filler (F)] The two-component dental composition of the present invention preferably further contains a filler (F).

[0119] As the filler (F), any filler can be used as long as it does not impair the effects of the present invention, and examples thereof include inorganic fillers, organic fillers, and composite fillers of inorganic fillers and organic fillers. The filler (F) may be used alone or in combination of two or more types.

[0120] The inorganic filler may be any of various glasses (mainly composed of silica, and optionally containing oxides of heavy metals, boron, aluminum, etc.). For example, glass powders of general compositions such as fused silica, quartz, soda lime silica glass, E glass, C glass, and borosilicate glass (Pyrex (registered trademark) glass); dental glass powders such as barium glass (manufactured by Schott, such as "GM27884" and "8235"; and "E-2000" and "E-3000" by Esstech), strontium borosilicate glass (manufactured by Esstech, such as "E-4000"), lanthanum glass ceramics (manufactured by Schott, such as "GM31684"), and fluoroaluminosilicate glass (manufactured by Schott, such as "GM35429", "G018-091", and "G018-117"); various ceramics; composite oxides such as silica-titania and silica-zirconia; diatomaceous earth, kaolin, clay minerals (montmorillonite, etc.); fluoride, etc.), activated clay, synthetic zeolite, mica, calcium fluoride, ytterbium fluoride, yttrium fluoride, calcium fluoride having a core-shell structure whose surface is coated with silica, ytterbium fluoride having a core-shell structure whose surface is coated with silica, yttrium fluoride having a core-shell structure whose surface is coated with silica, calcium phosphate, barium sulfate, zirconium dioxide, titanium dioxide, hydroxyapatite, calcium phosphate having a core-shell structure whose surface is coated with silica, barium sulfate having a core-shell structure whose surface is coated with silica, zirconium dioxide having a core-shell structure whose surface is coated with silica, titanium dioxide having a core-shell structure whose surface is coated with silica, and hydroxyapatite having a core-shell structure whose surface is coated with silica.Among these, from the viewpoint of strength, etc., various glasses, composite oxides such as silica-titania and silica-zirconia, calcium fluoride having a core-shell structure whose surface is coated with silica, ytterbium fluoride having a core-shell structure whose surface is coated with silica, yttrium fluoride having a core-shell structure whose surface is coated with silica, calcium phosphate having a core-shell structure whose surface is coated with silica, barium sulfate having a core-shell structure whose surface is coated with silica, zirconium dioxide having a core-shell structure whose surface is coated with silica, titanium dioxide having a core-shell structure whose surface is coated with silica, and hydroxyapatite having a core-shell structure whose surface is coated with silica are preferred. From the viewpoint of adhesiveness and handleability, fine particle silica having an average primary particle size of 0.001 to 10 μm is preferably used. Commercially available products include "Aerosil (registered trademark) OX50," "Aerosil (registered trademark) 50," "Aerosil (registered trademark) 200," "Aerosil (registered trademark) 380," "Aerosil (registered trademark) R972," and "Aerosil (registered trademark) 130" (all of which are trade names manufactured by Nippon Aerosil Co., Ltd.). In the present invention, when the inorganic filler is surface-treated as described below, the average particle size of the inorganic filler means the average particle size before the surface treatment.

[0121] Examples of organic fillers include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, crosslinked polymethyl methacrylate, crosslinked polyethyl methacrylate, polyamide, polyvinyl chloride, polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, and acrylonitrile-styrene-butadiene copolymer.

[0122] 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.

[0123] In this specification, the average particle size of the filler (F) can be determined by a laser diffraction scattering method or by observing the particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, and electron microscope observation is convenient for measuring the particle size of ultrafine particles less than 0.1 μm. 0.1 μm means the value measured by the laser diffraction scattering method.

[0124] Specifically, the laser diffraction scattering method can be performed by using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation) and measuring on a volume basis using a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium.

[0125] Specifically, electron microscope observation can be performed by taking a photograph of the filler particles with a scanning electron microscope (S-4000 model, manufactured by Hitachi, Ltd.) and measuring the particle diameters of particles (200 or more) observed within a unit field of view of the photograph using image analysis particle size distribution measurement software (Mac-View (manufactured by Mountec Co., Ltd.)). In this case, the particle diameter of the particles is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average particle diameter is calculated from the number of particles and their particle diameters.

[0126] In order to improve curability, mechanical strength, and handleability, the filler (F) may be surface-treated in advance with a known surface treatment agent such as a silane coupling agent. Examples of the surface treatment agent include silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

[0127] The two-component dental composition of the present invention may contain a separate silane coupling agent in addition to the silane coupling agent used as a surface treatment agent for the filler (F).

[0128] The silane coupling agent may be used alone or in combination of two or more. Any known silane coupling agent can be used without limitation. Specific examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, 5-(meth)acryloyloxypentyltrimethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, and 7-(meth)acryloyloxyheptyltrimethoxysilane. Examples thereof include acryloyloxyoctyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 9-(meth)acryloyloxynonyltrimethoxysilane, 10-(meth)acryloyloxydecyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, 8-(meth)acryloyloxyoctylmethyldimethoxysilane, 10-(meth)acryloyloxydecylmethyldimethoxysilane, 11-(meth)acryloyloxyundecylmethyldimethoxysilane, and (meth)acryloyloxymethylphenethyltrimethoxysilane.

[0129] From the viewpoint of adhesiveness, the content of the silane coupling agent is preferably 0.1 to 10.0 mass%, more preferably 0.5 to 9.0 mass%, even more preferably 1.0 to 8.0 mass%, and particularly preferably 1.2 to 7.0 mass%, based on the total mass (100 mass%) of the two-component dental composition of the present invention.

[0130] To enhance photocuring properties, the photopolymerization initiator (E) may be used in combination with a polymerization accelerator such as an aldehyde, a thiol compound, or a triazine compound substituted with a trihalomethyl group. A preferred embodiment of the present invention is a two-component dental composition that does not contain a triazine compound (e.g., a triazine compound substituted with a trihalomethyl group) other than the ultraviolet absorber (A). Examples of aldehydes include terephthalaldehyde and benzaldehyde derivatives. Examples of benzaldehyde derivatives include dimethylaminobenzaldehyde, p-methoxybenzaldehyde, p-ethoxybenzaldehyde, and p-n-octyloxybenzaldehyde. Examples of thiol compounds include 3-mercaptopropyltrimethoxysilane, 2-mercaptobenzoxazole, decanethiol, and thiobenzoic acid. The polymerization accelerators may be used alone or in combination.

[0131] Furthermore, the two-component dental composition of the present invention may contain a fluoride ion-releasing substance for the purpose of imparting acid resistance to tooth structure. The fluoride ion-releasing substance may be used alone or in combination of two or more. Examples of the fluoride ion-releasing substance include fluoride ion-releasing polymers such as copolymers of methyl methacrylate and methacrylic acid fluoride; fluoride ion-releasing substances such as cetylamine hydrofluoride; and inorganic fillers such as fluoroaluminosilicate glass, sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride.

[0132] The two-part dental composition of the present invention may contain additives such as a crosslinker, a silanol condensation catalyst, a stabilizer (polymerization inhibitor), a colorant (dye, pigment), and a fluorescent agent. The additives may be used alone or in combination. Examples of crosslinkers and silanol condensation catalysts that can be used include those described in International Publication No. 2019 / 004391. 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-butyl-4-methylphenol, and 2,6-di-t-butylphenol. In addition, antibacterial substances such as cetylpyridinium chloride, benzalkonium chloride, (meth)acryloyloxydodecylpyridinium bromide, (meth)acryloyloxyhexadecylpyridinium chloride, (meth)acryloyloxydecylammonium chloride, triclosan, etc. may be blended in. One type of antibacterial substance may be used alone, or two or more types may be used in combination.

[0133] In a preferred embodiment, the two-part dental composition of the present invention is composed of a first part and a second part, and the first part preferably contains an ultraviolet absorber (A), a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) having no acidic group), and a chemical polymerization accelerator (D), and more preferably contains an ultraviolet absorber (A), a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) having no acidic group), a chemical polymerization accelerator (D), and a filler (F). In the case of dual-cure polymerization, the first part preferably further contains a photopolymerization initiator (E). The second agent preferably contains a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group) and a chemical polymerization initiator (C), more preferably a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), and even more preferably a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group), a chemical polymerization initiator (C), a chemical polymerization accelerator (D), and a filler (F). When enhancing the adhesiveness of the two-part dental composition of the present invention, the polymerizable monomer (B) of the second agent is particularly preferably a polymerizable monomer (B-1) having an acidic group and a polymerizable monomer (B-2) not having an acidic group.

[0134] In another preferred embodiment, the two-part dental composition of the present invention is composed of a first part and a second part. The first part preferably contains a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) having no acidic group) and a chemical polymerization accelerator (D), and more preferably contains a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) having no acidic group), a chemical polymerization accelerator (D), and a filler (F). The second agent preferably contains an ultraviolet absorber (A), a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group), and a chemical polymerization initiator (C), more preferably contains an ultraviolet absorber (A), a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), and more preferably contains an ultraviolet absorber (A), a polymerizable monomer (B) (e.g., a polymerizable monomer (B-2) not having an acidic group), a chemical polymerization initiator (C), a chemical polymerization accelerator (D), and a filler (F). In the case of dual-cure polymerization, the second agent preferably further contains a photopolymerization initiator (E). In the case of enhancing the adhesiveness of the two-part dental composition of the present invention, the polymerizable monomer (B) of the second agent more preferably contains a polymerizable monomer (B-1) having an acidic group and a polymerizable monomer (B-2) not having an acidic group.

[0135] The two-component dental composition of the present invention preferably does not contain a solvent (water, organic solvent). In a preferred embodiment, the content of the solvent (water, organic solvent) in the two-component dental composition of the present invention is preferably less than 5.0% by mass, more preferably less than 1.0% by mass, even more preferably less than 0.5% by mass, particularly preferably less than 0.1% by mass, and most preferably less than 0.01% by mass.

[0136] The two-component dental composition of the present invention can be produced, for example, by mixing all ingredients other than the powdery ingredients (such as the filler (F)) to obtain a solution, and then adding the powdery ingredients.

[0137] The present invention includes embodiments in which all or part of the above configurations are combined in various ways within the scope of the technical concept of the present invention, as long as the effects of the present invention are achieved.

[0138] The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples, and many modifications can be made by those skilled in the art within the scope of the technical concept of the present invention. The abbreviations and symbols used below are as follows:

[0139] [Ultraviolet absorber (A)] T1: bisethylhexyloxyphenol methoxyphenyl triazine T2: 2-[4,6-bis(biphenyl-4-yl)-1,3,5-triazin-2-yl]-5-[(2-ethylhexyl)oxy]phenol T3: 2,4,6-tris[4-(hexyloxy)-2-hydroxy-3-methylphenyl]-1,3,5-triazine T4: 2,4-bis(2,4-dimethylphenyl)-6-(2-hydroxy-4-n-octyloxyphenyl)-1,3,5-triazine

[0140] [Ultraviolet absorbers other than ultraviolet absorber (A)] B1: 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole B2: 2-(2H-benzotriazol-2-yl)-4-methyl-6-dodecylphenol O2: 2-ethylhexyl 4-methoxycinnamate

[0141] [Polymerizable Monomer (B-1) Having an Acidic Group] MDP: 10-methacryloyloxydecyl dihydrogen phosphate

[0142] [Polymerizable monomer (B-2) having no acidic group] UDMA: 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate HEMA: 2-hydroxyethyl methacrylate Bis-GMA: 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane 3G: triethylene glycol dimethacrylate NPG: neopentyl glycol dimethacrylate D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6) #801: 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane POBMA: m-phenoxybenzyl methacrylate

[0143] [Chemical polymerization initiator (C)] BPB: t-butyl peroxybenzoate KPS: potassium peroxodisulfate BPO: benzoyl peroxide THP: 1,1,3,3-tetramethylbutyl hydroperoxide

[0144] [Chemical polymerization accelerator (D)] TPSS: sodium 2,4,6-triisopropylbenzenesulfinate DEPT: N,N-bis(2-hydroxyethyl)-p-toluidine BTA: 1H-benzotriazole NAA: sodium sulfite CuA: copper(II) acetate PyTU: 1-(2-pyridyl)-2-thiourea VOAA: vanadyl acetylacetonate(IV) NMDEA: N-methyldiethanolamine

[0145] [Photopolymerization initiator (E)] CQ: dl-camphorquinone, DABE: ethyl 4-(N,N-dimethylamino)benzoate, TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide

[0146] [Filler (F)] Ba1: Silane-treated barium glass powder: Barium glass (trade name "Raysorb E-3000", manufactured by Estec Co., Ltd.) was pulverized in a ball mill to obtain a barium glass powder having an average particle size of approximately 2.4 μm. 100 parts by mass of this barium glass powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane in a conventional manner to obtain a silane-treated barium glass powder. Ba2: Silane-treated barium glass powder: Barium glass (trade name "Raysorb E-3000", manufactured by Estec Co., Ltd.) was pulverized in a ball mill to obtain a barium glass powder having an average particle size of approximately 2.4 μm. 100 parts by mass of this barium glass powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane in a conventional manner to obtain a silane-treated barium glass powder. Al2O3: Trade name "AEROXIDE (registered trademark) Alu C", average particle size: 13 nm, manufactured by Nippon Aerosil Co., Ltd. SiO2: Fine particle silica "Aerosil (registered trademark) R972", average particle size: 16 nm, manufactured by Nippon Aerosil Co., Ltd. Ba3: 100 g of barium glass (8235 K4 average particle size: 7 μm, manufactured by SCHOTT), 6 g of γ-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3 mass% acetic acid aqueous solution were placed in a three-necked flask and stirred for 2 hours at room temperature. After removing water by freeze-drying, the mixture was heat-treated at 80 ° C for 5 hours to obtain silane-treated barium glass. Ba4: 100 g of barium glass (8235 UF0.7 grade, average particle size: 0.7 μm, manufactured by SCHOTT), 6 g of γ-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3% by mass acetic acid aqueous solution were placed in a three-neck flask and stirred for 2 hours at room temperature. After removing water by freeze-drying, the mixture was heat-treated at 80°C for 5 hours to obtain silane-treated barium glass. G018-090UF2.0: 100 g of fluoroaluminosilicate glass (trade name "G018-090", grade: UF2.0, average particle size: 2.0 μm, manufactured by SCHOTT), 6 g of γ-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3% by mass acetic acid aqueous solution were placed in a three-neck flask and stirred for 2 hours at room temperature.After removing water by freeze-drying, the glass was heat-treated at 80° C. for 5 hours to obtain silane-treated fluoroaluminosilicate glass. Ar380: Hydrophilic fumed silica "Aerosil (registered trademark) 380", average primary particle size: 0.007 μm, manufactured by Nippon Aerosil Co., Ltd.

[0147] [Others] γMPS: γ-methacryloyloxypropyltrimethoxysilane (silane coupling agent) BHT: 2,6-di-t-butyl-4-methylphenol (polymerization inhibitor) TCT: 2,4,6-tris(trichloromethyl)-s-triazine

[0148] Examples 1-1 to 1-8, 2-1 to 2-4, 3-1 to 3-2, 4-1 to 4-2, and Comparative Examples 1-1 to 1-7, 2-1 to 2-5, 3-1 to 3-3, 4-1 to 4-3 First and second agents were prepared with the compositions shown in Tables 2 to 6. The first agent was prepared by blending all components except the powdered components (filler, TPSS, and NAA), stirring the mixture to form a uniform solution, and then kneading and degassing the powdered components. The powdered components in the first agent were dispersed in a powdery state. The second agent was prepared by blending all components except the powdered components (filler and KPS), stirring the mixture to form a uniform solution, and then kneading and degassing the powdered components. The powdered components in the second agent were dispersed in a powdery state. The two agents were each filled into a double syringe (5 mL double syringe manufactured by Mixpac), and the plungers were set. A mixing tip (Mixpac) was attached to the tip of a double syringe, and the two components were automatically mixed at a volume ratio of 1:1. The mixture was used for evaluation as a two-component dental composition. Tests were conducted using the methods described below. The results are shown in Tables 2 to 6. Table 1 also shows the properties of the ultraviolet absorber (A) and ultraviolet absorbers other than ultraviolet absorber (A) used.

[0149] [Measurement of maximum absorption wavelength] Ethyl acetate was used as a solvent, and the concentration was 3×10 -5 A solution of 100 mol / L was prepared, and the maximum absorption wavelength was measured in the wavelength range of 250 nm to 500 nm using a spectrophotometer (product name "UH5200", manufactured by Hitachi High-Technologies Corporation) using a quartz cell with an optical path length of 10 mm (arithmetic mean value of n = 2).

[0150] [Evaluation of Color Tone Stability] The first and second parts of each two-component dental composition according to the Examples and Comparative Examples were thoroughly mixed at a volume ratio of 1:1 for 10 seconds to prepare a paste (two-component dental composition). A 1 mm-thick mold with a 15 mm diameter through-hole was placed on a glass slide, and the paste was quickly filled after preparation. A PET sheet and a glass slide were then placed on top and pressed together. Next, using a dental polymerization light irradiator (trade name "PenCure 2000", manufactured by Morita Corporation), the paste was irradiated for 10 seconds at five locations on each side so that the entire paste was exposed to light, yielding a cured product as a test specimen. The cured product was then placed in a desiccator and stored in a dark place at 37°C for 24 hours. The color was measured using a spectrophotometer (trade name "SE6000", manufactured by Nippon Denshoku Industries Co., Ltd.) to determine the chromaticity before irradiation. The cured product was then subjected to a xenon accelerated weathering test using a Solarbox 1500e (trade name, manufactured by Bunkoukeiki Co., Ltd.) in water at 37°C with an irradiation illuminance of 500 to 550 W / m 2 After irradiation, the cured product was measured for color using a spectrophotometer, and the measured color was taken as the chromaticity after irradiation. The amount of color change ΔE from the chromaticity before and after irradiation was calculated. * The color tone change ΔE* can be calculated using the following formula, and the smaller the value, the smaller the color tone change and the higher the color tone stability against sunlight. ΔE * = {(ΔL * ) 2 + (Δa * ) 2 + (Δb * ) 2} 1 / 2 ; ΔL * = L1 * -L2 * ; Δa * = a1 * -a2 * ; Δb * = b1 * -b2 * : In addition, L1 * indicates the brightness index before irradiation, and a1 * and b1 * indicates the color quality index before irradiation, and L2 * indicates the brightness index after irradiation, and a2* and b2 * indicates the color quality index after irradiation. Evaluations were carried out on a cured product of a composition prepared by mixing the first and second parts immediately after preparation, and on a cured product of a composition prepared by mixing the first and second parts after storing them in the double syringe described above at 60°C for two weeks to simulate the condition of long-term storage. In Tables 2 to 6, the evaluation of the former is shown as "ΔE * (initial)" and the latter evaluation is "ΔE * (after temperature acceleration)

[0151] [Unpolymerized Thickness (Photo-Cured)] A polyester film was placed on a glass slide, and a 1 mm thick Teflon (registered trademark) mold with a 5 mm diameter hole was placed on top of it. The two-component dental composition prepared above was filled, and the mass was measured (X) [g]. Light was irradiated from above for 10 seconds using a dental polymerization light irradiator (trade name "PenCure 2000", manufactured by Morita Corporation). Thereafter, the uncured portion was wiped off with a JK Wiper (registered trademark) (manufactured by Nippon Paper Crecia Co., Ltd.), and the mass was measured (Y) [g]. The unpolymerized thickness was calculated using the following formula (arithmetic mean value for n = 5): Unpolymerized Thickness (μm) = ((X) - (Y)) / Specific Gravity [g / mm 3 ]÷Area [mm 2 ]×1000

[0152] [Unpolymerized Thickness (Chemical Curing)] A polyester film was placed on a glass slide, and a 1 mm thick Teflon (registered trademark) mold with a 5 mm diameter hole was placed on top of it. The two-component dental composition prepared above was filled, and the mass was measured (X) [g]. The composition was then cured at a constant temperature of 37°C for 10 minutes, and the uncured portion was wiped off with a JK Wiper (registered trademark) (manufactured by Nippon Paper Crecia Co., Ltd.), and the mass was measured (Y) [g]. The unpolymerized thickness was calculated using the following formula (arithmetic mean value for n = 5): Unpolymerized Thickness (μm) = ((X) - (Y)) / Specific Gravity [g / mm 3 ]÷Area [mm 2 ]×1000

[0153]

[0154]

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[0158]

[0159] As shown in Tables 2 to 6, the two-component dental compositions of the present invention, regardless of which example they were prepared in, showed little change in color immediately after preparation and excellent color stability. Furthermore, the two-component dental compositions of the present invention, regardless of which example they were prepared in, showed little change in color even when continuously exposed to heat and also showed excellent long-term color stability. Furthermore, as shown in Examples 1-1 to 1-8, it was confirmed that the two-component dental compositions of the present invention can reduce the thickness of the unpolymerized layer.

[0160] On the other hand, the two-component dental compositions prepared in Comparative Examples 1-1, 1-3, 1-5, 2-1, 3-1, and 4-1 showed significant color change and lacked color stability. Furthermore, the two-component dental compositions prepared in each Comparative Example showed significant color change when continuously exposed to heat, confirming poor long-term color stability. This is thought to be due to the UV absorber adopting a quinoid structure and extending the conjugation, resulting in a significant shift in the peak wavelength to the longer wavelength side of the light absorption spectrum, or due to coordination with the metal catalyst in the system, resulting in the generation of a new light absorption peak on the longer wavelength side due to charge transfer between the metal and the ligand. Furthermore, the two-component dental composition of Comparative Example 1-7, which did not contain the chemical polymerization accelerator (D), did not harden, and the cured product could not be evaluated.

[0161] The two-component dental composition of the present invention can be suitably used for dental restorative treatment. The two-component dental composition of the present invention can also be suitably used as a dental cement, particularly as a self-adhesive cement.

Claims

1. A two-component dental composition comprising an ultraviolet absorber (A), a polymerizable monomer (B), a chemical polymerization initiator (C), and a chemical polymerization accelerator (D), wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber having a maximum absorption wavelength in a wavelength band of 310 nm or more and 400 nm or less.

2. The two-component dental composition according to claim 1, wherein the ultraviolet absorber (A) is a triazine-based ultraviolet absorber represented by the following general formula (1). (R 1 represents an alkyl group or an alkoxy group, and R 2 and R 3 each independently represent a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, or a halogen atom, and R 4 , R 5 , and R 6 each independently represent a hydrogen atom or an alkyl group, and R 7 , and R 8 each independently represent a hydrogen atom, a hydroxy group, an alkyl group, an alkoxy group, an aryl group, or a halogen atom, and the alkyl groups and alkoxy groups of R 1 to R 8 may have substituents.) 3. The two-component dental composition according to claim 1 or 2, wherein the ultraviolet absorber (A) is 85 parts by mass or more based on 100 parts by mass in total of the ultraviolet absorbers.

4. The R of the ultraviolet absorber (A) 1 The two-component dental composition according to claim 2, wherein is an alkyl group or an alkoxy group having 1 to 15 carbon atoms.

5. The R of the ultraviolet absorber (A) 1 The two-component dental composition according to claim 4, wherein is a branched alkyl group or alkoxy group having 3 to 15 carbon atoms.

6. The R of the ultraviolet absorber (A) 1 is a 2-ethylhexyloxy group, and the two-component dental composition according to claim 5.

7. The two-component dental composition according to claim 6, wherein the ultraviolet absorber (A) is bis(ethylhexyl)oxyphenol methoxyphenyltriazine and / or 2-[4,6-bis(biphenyl-4-yl)-1,3,5-triazin-2-yl]-5-[(2-ethylhexyl)oxy]phenol.

8. The two-component dental composition according to claim 1 or 2, wherein the chemical polymerization initiator (C) is a peroxide.

9. The two-component dental composition according to claim 1 or 2, wherein the chemical polymerization accelerator (D) is at least one selected from the group consisting of aromatic sulfinic acids and their salts, sulfur-containing reducing inorganic compounds, thiourea compounds, ascorbic acid compounds, benzotriazole compounds, benzimidazole compounds, and transition metal compounds.

10. The two-component dental composition according to claim 1 or 2, further comprising a photoinitiator (E).

11. The two-component dental composition according to claim 1 or 2, further comprising a filler (F).

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