Dental curable composition

Abstract

To provide a dental curable composition that exhibits superior paste properties and yields a cured product with excellent mechanical strength and polishing properties, and an inorganic aggregate filler for use therein.SOLUTION: A dental curable composition includes a polymerizable monomer (A), a polymerization initiator (B), and an inorganic aggregate filler (C). The inorganic aggregate filler (C) satisfies all of the following conditions (c1), (c2) and (c3): (c1) primary particles constituting the inorganic aggregate filler have an irregular shape (excluding spherical shapes); (c2) the primary particles constituting the inorganic aggregate filler have an average particle size of 650 nm or less; and (c3) the inorganic aggregate filler has a micro-compression hardness of 10-300 MPa.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a dental hardenable composition. More specifically, the present invention relates to a dental hardenable composition that has good paste properties and produces a hardened product having excellent mechanical strength and polishability. [Background technology]

[0002] Dental hardenable compositions consisting of polymerizable monomers, inorganic fillers and polymerization initiators are called composite resins, and are the most widely used dental materials today as filling and restoring materials for missing teeth and cavities. Such dental hardenable compositions are required to have the following properties: The hardened product after polymerization and hardening must have sufficient mechanical strength, hardness, abrasion resistance against biting in the oral cavity, surface smoothness, color compatibility with natural teeth, transparency, etc. to be able to replace natural teeth. Furthermore, in the paste state before polymerization and hardening, it is desired that the material has appropriate fluidity and formability, does not adhere to dental instruments, is not sticky, and is easy for clinicians to handle (high operability).

[0003] The properties of such dental hardenable compositions are affected by the material, shape, particle size, and content of the inorganic filler used therein. For example, when a large inorganic filler having an average particle size of 1 μm or more is used, the filling rate in the polymerizable monomer can be easily increased, and sufficient mechanical strength of the cured product and high paste workability can be obtained, but there is a problem that it is difficult to obtain sufficient gloss even after finish polishing. On the other hand, when inorganic ultrafine particle filler having an average particle size of less than 1 μm is used, the polishing smoothness of the cured product is improved, but when the inorganic ultrafine particle filler is kneaded into a polymerizable monomer, the viscosity of the paste increases significantly, making it difficult to increase the filler content, resulting in problems such as a decrease in the mechanical strength of the cured product and a sticky paste composition before polymerization, resulting in poor operability.

[0004] For these reasons, it is difficult to achieve a good balance between improving the mechanical strength of the cured product, the smoothness when polished, and the workability of the paste.

[0005] In recent years, in the development of dental composite resins, methods have been investigated that ensure polishing lubricity by using inorganic ultrafine particles as the main component, while improving the conventional problems of paste stickiness and / or insufficient mechanical strength (e.g., Patent Documents 1 and 2). Patent Document 1 describes a dental composite resin that uses an organic-inorganic composite filler with an average particle size of 1 to 30 μm, which is obtained by mixing ultrafine silica particles with an average particle size of 0.01 to 0.05 μm with a polymerizable monomer, polymerizing and hardening the mixture, and then pulverizing the mixture. Patent Document 2 describes a filler for a dental composite restorative material and a filled composite material which are obtained by agglomerating metal oxide particles having an average particle size of 0.05 μm or more and 1 μm or less and heat treating the particles. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 63-88110 [Patent Document 2] Japanese Patent Application Publication No. 7-196431 Summary of the Invention [Problem to be solved by the invention]

[0007] In the dental composite resin described in Patent Document 1, which contains ultrafine silica particles as an organic-inorganic composite filler, the particle diameter of the organic-inorganic composite filler itself is large, which significantly improves the viscosity increase and stickiness of the paste and also improves the mechanical strength of the cured product. However, in Patent Document 1, the actual inorganic filler content could not be increased sufficiently, and furthermore, the surface of the organic-inorganic composite filler and the polymerizable monomer used in combination therewith could not be integrated through a substantial chemical bond, so that the bonding strength between the filler and the polymerizable monomer interface was weak, and there was room for improvement in the mechanical strength of the cured product of the composite resin.

[0008] Similarly, in the filled composite material containing the filler for dental composite restorative materials described in Patent Document 2, the actual inorganic filler content could not be increased sufficiently, and there was room for improvement in the mechanical strength of the cured product.

[0009] An object of the present invention is to provide a dental curable composition which has good paste properties and produces a cured product having excellent mechanical strength and polishing properties, and an inorganic aggregate filler for use therein. [Means for solving the problem]

[0010] As a result of extensive research to solve the above problems, the inventors have found that the above problems can be solved by using an inorganic agglomerated filler in which the average particle size of the primary particles is within a specific range, the shape of the primary particles is irregular, and the filler has a specific microcompression hardness. Based on this finding, the inventors have conducted further research and have completed the present invention.

[0011] The present invention includes the following inventions. [1] A composition comprising a polymerizable monomer (A), a polymerization initiator (B), and an inorganic aggregate filler (C), The inorganic aggregate filler (C) is selected from the following (c1), (c2) and (c3): (c1) The primary particles constituting the inorganic aggregate filler have an irregular shape (except for a spherical shape); (c2) the average particle size of the primary particles constituting the inorganic aggregate filler is 650 nm or less; (c3) the microcompression hardness of the inorganic aggregate filler is 10 to 300 MPa; A dental hardenable composition which simultaneously satisfies the above requirements. [2] The dental hardenable composition according to [1], wherein the inorganic aggregate filler (C) has a spherical shape. [3] The dental curable composition according to [1] or [2], wherein the content of the inorganic aggregate filler (C) is 5 to 50 mass %. [4] The specific surface area of ​​the inorganic aggregate filler (C) is 80 m 2 / g or less. [5] The dental curable composition according to any one of [1] to [4], further comprising a non-aggregated filler (D) having an average primary particle size of 500 nm or less. [6] The dental curable composition according to [5], wherein the content of the non-aggregating filler (D) is 5 to 45 mass %. [7] Paragraphs (c1), (c2) and (c3) below: (c1) The primary particles constituting the inorganic aggregate filler have an irregular shape (except for a spherical shape); (c2) the average particle size of the primary particles constituting the inorganic aggregate filler is 650 nm or less; (c3) The inorganic aggregate filler has a microcompression hardness of 10 to 300 MPa. Dental inorganic aggregate filler (C) that simultaneously satisfies the above requirements. [8] A method for producing an inorganic agglomerated filler, comprising: a mixing step of mixing a dispersion obtained by dispersing inorganic particles having an average primary particle size of 650 nm or less in a solvent with a binder containing at least one metal oxide selected from the group consisting of silicon, barium, aluminum, and transition metal elements of Groups 3 to 11 to obtain a mixed solution; a drying step of drying the mixed solution to obtain a dried body; and a firing step of firing the dried body. [9] The method for producing an inorganic aggregate filler according to [8], wherein in the mixing step, the amount of the binder added is 1 to 35 parts by mass per 100 parts by mass of the inorganic particles.

[10] The binder is represented by the following general formula (1): R 1 n SiY 4-n (1) (In the formula, R 1represents a substituted or unsubstituted hydrocarbon group having 1 to 25 carbon atoms, Y represents an alkoxy group having 1 to 4 carbon atoms, an acyloxy group having 1 to 5 carbon atoms, a hydroxy group, a halogen atom, or a hydrogen atom, and n is an integer of 0 to 3, with the proviso that R 1 When there are multiple X's, they may be the same or different. The method for producing an inorganic aggregate filler according to [8] or [9], wherein the silane coupling agent is represented by the formula:

[11] The method for producing an inorganic aggregate filler according to any one of [8] to

[10] , wherein the drying step is spray drying.

[12] The method for producing an inorganic aggregate filler according to any one of [8] to

[11] , wherein the firing temperature in the firing step is 30 to 80% of the melting temperature of the primary particles or the melting point temperature of the main component forming the primary particles.

[13] The method for producing an inorganic aggregate filler according to any one of [8] to

[12] , wherein the firing temperature in the firing step is 600 to 800° C. Effect of the Invention

[0012] The present invention can provide a dental curable composition which has good paste properties and produces a cured product having excellent mechanical strength and polishability, and an inorganic aggregate filler used therein. [Brief description of the drawings]

[0013] [Figure 1] FIG. 2 is an explanatory diagram of the measurement principle of the microcompression hardness of the inorganic aggregate filler of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, each embodiment of the present invention will be described. In this specification, "(meth)acrylic" is a general term for methacrylic and acrylic, and the same applies to similar expressions (such as "(meth)acrylic acid" and "(meth)acrylonitrile"). In addition, in this specification, the upper and lower limits of numerical ranges (contents of each component, values ​​calculated from each component, and each physical property, etc.) can be combined as appropriate.

[0015] One embodiment of the present invention includes a composition comprising a polymerizable monomer (A), a polymerization initiator (B), and a dental inorganic aggregate filler (C), The dental inorganic aggregate filler (C) is selected from the group consisting of the following (c1), (c2) and (c3): (c1) The primary particles constituting the inorganic aggregate filler have an irregular shape (excluding spherical particles); (c2) the average particle size of the primary particles constituting the inorganic aggregate filler is 650 nm or less; (c3) The inorganic aggregate filler has a microcompression hardness of 10 Pa to 300 MPa. The dental hardenable composition satisfies the above requirements at the same time.

[0016] The reasons why the dental hardenable composition of the present invention has good paste properties and the cured product has excellent mechanical strength and polishability are believed to be as follows. The dental inorganic agglomerated filler (C) (hereinafter also referred to as "cluster filler") has an irregular primary particle shape, and therefore when it is kneaded with a resin component such as a polymerizable monomer to form a dental hardenable composition, the resin component adheres strongly to the dental inorganic agglomerated filler (C), resulting in excellent mechanical strength of the hardened product. In addition, the dental inorganic agglomerated filler (C) has a small average particle size of the primary particles, and therefore has excellent abrasive properties. Furthermore, since the dental inorganic aggregate filler (C) has a microcompression hardness of a predetermined value or more, in the manufacturing process in which the inorganic aggregate filler and a polymerizable monomer are kneaded to obtain a paste-like dental hardenable composition, excessive disintegration of the aggregated particles due to shear pressure during kneading can be suppressed, and the primary particles constituting the aggregated particles do not crumble, and the particle size of the inorganic aggregate filler can be suppressed from becoming small. As a result, when the dental hardenable composition is obtained, good paste properties can be obtained. Furthermore, if the specified microcompression hardness is too high, the aggregated particles are hardly disintegrated even by the shear pressure during the kneading, and the particle size of the inorganic aggregated filler remains large. As a result, even when the dental hardenable composition is hardened, a part of the primary particles does not crumble from the hardened product, and the polishing properties are poor. In contrast, when the microcompression hardness is equal to or less than a predetermined value, the aggregated particles are hardly disintegrated even by shear pressure during the kneading, and the particle size of the inorganic aggregated filler remains large. Therefore, after the dental curable composition is produced, when the dental curable composition is polymerized and cured and then the cured product is polished, part of the primary particles can be broken down from the aggregated particles by polishing, resulting in excellent polishing properties. In the present invention, it is believed that the above-mentioned excellent effects can be achieved by focusing particularly on the hardness of the inorganic aggregate filler, which is a secondary particle, and further by setting the microcompression hardness within a specific range.

[0017] In this specification, the term "microcompression hardness" refers to the crushing strength of a single granule measured by a microcompression tester in accordance with JIS R 1639-5: 2007. Examples of the microcompression tester include microcompression testers (MCT-510, MCT-511, MCT-210, MCT-211) (MCT series) manufactured by Shimadzu Corporation. As shown in FIG. 1, the microcompressive hardness is a value evaluated by applying a load of a predetermined test force 3 (load: 9.8 to 50 mN) via an indenter 2 to each inorganic particle 1 to be measured, and automatically measuring the amount of deformation as the compression displacement 4, and is derived from the particle diameter (mm) and the crushing test force (N).

[0018] Each component used in the dental hardenable composition of the present invention will be described below.

[0019] <Polymerizable monomer (A)> As the polymerizable monomer (A) used in the dental curable composition of the present invention, a radically polymerizable monomer is suitably used. Specific examples of the radical polymerizable monomer in the polymerizable monomer (A) include (meth)acrylate-based polymerizable monomers, (meth)acrylamide-based polymerizable monomers, esters such as α-cyanoacrylic acid, (meth)acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, and itaconic acid, 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. The polymerizable monomer (A) is classified into a polymerizable monomer (A-1) having an acidic group and a polymerizable monomer (A-2) not having an acidic group.

[0020] Polymerizable monomer having an acidic group (A-1) In order to impart adhesion to tooth structure, the polymerizable monomer (A-1) having an acidic group is preferred. Examples of the polymerizable monomer (A-1) having an acidic group used in the present invention include polymerizable monomers having at least one acidic group such as a phosphoric acid group, a pyrophosphoric acid group, a thiophosphoric acid group, a phosphonic acid group, a carboxylic acid group, or a sulfonic acid group. The polymerizable monomer (A-1) having an acidic group may be used alone or in combination of two or more kinds. Specific examples of the polymerizable monomer (A-1) having an acidic group are given below.

[0021] 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)acryloyloxypentyl dihydrogen phosphate, 14-(meth)acryloyloxyhexyl dihydrogen phosphate, 15-(meth)acryloyloxyhexyl dihydrogen phosphate, 16-(meth)acryloyloxyhexyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxyhexyl dihydrogen phosphate, 19-(meth)acryloyloxyhexyl dihydrogen phosphate, 20-(meth)acryloyloxyhexyl dihydrogen phosphate, 21-(meth)acryloyloxyhexyl dihydrogen phosphate, 22-(meth)acryloyloxyhexyl dihydrogen phosphate, 23-(meth)acryloyloxyhexyl dihydrogen phosphate, 24-(meth)acryloyloxyhexyl dihydrogen phosphate, 25-(meth)acryloyloxyhexyl dihydrogen phosphate, 26-(meth)acryloyloxyhexyl dihydrogen phosphate, 27-(meth)acryloyloxy 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 phosphate, bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxydecyl]hydrogen phosphate, 1,3-di Examples of suitable acryloyloxypropyl-2-dihydrogen phosphate include (meth)acryloyloxyethyl phenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogen phosphate, 2-methacryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, 2-methacryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0022] Examples of polymerizable monomers 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.

[0023] Examples of polymerizable monomers 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. Examples of suitable acryloyloxyalkyl thiophosphates include acryloyloxyalkyl 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.

[0024] Examples of the polymerizable monomer having a phosphonic acid group include 2-(meth)acryloyloxyethyl phenyl phosphonate, 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonoacetate, 10-(meth)acryloyloxydecyl-3-phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0025] Examples of the polymerizable monomer having a carboxylic acid group include a monofunctional (meth)acrylic acid ester having one carboxyl group or an acid anhydride group thereof in the molecule, and a monofunctional (meth)acrylic acid ester having multiple carboxyl groups or acid anhydride groups thereof in the molecule.

[0026] Examples of monofunctional polymerizable monomers 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)acryloylthio 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, N-(meth)acryloyl-4-aminosalicylic acid, and compounds in which the carboxyl group of these compounds is converted to an acid anhydride group.

[0027] 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 ... Examples of the acryloyloxyethyl ester include butyl acryloyloxy trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethyl naphthalene-1,2,6-tricarboxylic acid anhydride, 6-(meth)acryloyloxyethyl naphthalene-2,3,6-tricarboxylic acid anhydride, 4-(meth)acryloyloxyethyl carbonylpropionoyl-1,8-naphthalic acid anhydride, and 4-(meth)acryloyloxyethyl naphthalene-1,8-tricarboxylic acid anhydride.

[0028] An example of the polymerizable monomer having a sulfonic acid group is 2-sulfoethyl (meth)acrylate.

[0029] Among the above-mentioned polymerizable monomers (A-1) having an acidic group, from the viewpoint of good adhesive strength when used as a dental hardenable composition, it is preferable to contain a polymerizable monomer having a phosphoric acid group or a polymerizable monomer having a carboxylic acid group, and examples of the polymerizable monomers (A-1) having an acidic 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)acryloyl Oxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 11-(meth)acryloyloxyundecane-1,1-Dicarboxylic acid and a mixture of 2-methacryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, and 20-(meth)acryloyloxyicosyl dihydrogen phosphate are even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being the most preferred from the viewpoint of balance with curability.

[0030] When the dental curable composition of the present invention contains a polymerizable monomer (A-1) having an acidic group, the content of the polymerizable monomer (A-1) having an acidic group is, from the viewpoint of adhesion to tooth structure, preferably 1 to 40 parts by mass, more preferably 2.5 to 35 parts by mass, and even more preferably 5 to 30 parts by mass, per 100 parts by mass of the polymerizable monomer (A).

[0031] Polymerizable monomers without acidic groups (A-2) The polymerizable monomer (A-2) having no acidic group in the present invention includes a hydrophobic polymerizable monomer (A-2a) having no acidic group and having a solubility of less than 10% by mass in water at 25° C., and a hydrophilic polymerizable monomer (A-2b) having no acidic group and having a solubility of 10% by mass or more in water at 25° C. The polymerizable monomer (A-2) having no acidic group may be used alone or in combination of two or more kinds.

[0032] Hydrophobic polymerizable monomers without acidic groups (A-2a) The hydrophobic polymerizable monomer (A-2a) having no acidic group (hereinafter, sometimes simply referred to as "hydrophobic polymerizable monomer (A-2a)") improves the handleability of the dental hardenable composition and the mechanical strength of the hardened product. As the hydrophobic polymerizable monomer (A-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. The hydrophobic polymerizable monomer (A-2a) means a polymerizable monomer which does not have an acidic group and has a solubility in water at 25° C. of less than 10% by mass. The hydrophobic polymerizable monomer (A-2a) may be used alone or in combination of two or more kinds. Examples of the hydrophobic polymerizable monomer (A-2a) include, in addition to hydrophobic monofunctional polymerizable monomers, crosslinkable polymerizable monomers such as aromatic compound-based bifunctional polymerizable monomers, aliphatic compound-based bifunctional polymerizable monomers, and trifunctional or higher polymerizable monomers.

[0033] Examples of hydrophobic monofunctional polymerizable monomers include methyl methacrylate, ethyl methacrylate, butyl methacrylate, benzyl methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, p-cumyl-phenoxyethylene glycol methacrylate (CMP-1E), m-phenoxybenzyl methacrylate (commonly known as "POBMA"), stearyl methacrylate, dicyclopentanyl methacrylate, butoxydiethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, and mixtures thereof. Among these, benzyl methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, CMP-1E, POBMA, and mixtures thereof are preferred.

[0034] Examples of aromatic 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 the like. 2-(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, and the like. Among these, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles added of ethoxy groups: 2.6, commonly known as "D-2.6E"), 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane are preferred.

[0035] Examples of the aliphatic compound-based bifunctional polymerizable monomer include glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)di(meth)acrylate, N-methacryloyloxyethylacrylamide, and N-methacryloyloxypropylamide. Among these, triethylene glycol diacrylate, triethylene glycol dimethacrylate (commonly known as "3G"), neopentyl glycol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl) dimethacrylate (commonly known as "UDMA"), 1,10-decanediol dimethacrylate (commonly known as "DD"), 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl) dimethacrylate, and N-methacryloyloxyethyl acrylamide (commonly known as "MAEA") are preferred.

[0036] Examples of trifunctional or higher 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, 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane, etc. Among these, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate is preferred.

[0037] Among the above hydrophobic polymerizable monomers (A-2a), from the viewpoint of mechanical strength and operability of the cured product, bifunctional polymerizable monomers based on aromatic compounds and bifunctional polymerizable monomers based on aliphatic compounds are preferably used. As the aromatic compound-based bifunctional polymerizable monomer, Bis-GMA and D-2.6E are preferred. As the aliphatic compound-based bifunctional polymerizable monomer, glycerol di(meth)acrylate, 3G, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, DD, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, UDMA, and MAEA are preferred.

[0038] Among the above hydrophobic polymerizable monomers (A-2a), from the viewpoint of good adhesion to tooth structure when used as a dental hardenable composition, Bis-GMA, D-2.6E, 3G, UDMA, DD, and MAEA are more preferred, and Bis-GMA, D-2.6E, 3G, UDMA, and MAEA are even more preferred.

[0039] When the dental curable composition of the present invention contains a polymerizable monomer (A-1) having an acidic group, the content of the hydrophobic polymerizable monomer (A-2a) in the dental curable composition of the present invention is preferably 20 to 99 parts by mass, more preferably 40 to 95 parts by mass, and even more preferably 60 to 95 parts by mass, in 100 parts by mass of the polymerizable monomer (A). When the content of the hydrophobic polymerizable monomer (A-2a) is within the above range, the dental curable composition has excellent wettability to tooth structure, and the combination with the polymerizable monomer (A-1) having an acidic group provides the desired adhesiveness, and the cured product has the desired mechanical strength. In an embodiment in which the dental curable composition of the present invention does not contain a polymerizable monomer (A-1) having an acidic group, the content of the hydrophobic polymerizable monomer (A-2a) in the dental curable composition is preferably 50 to 100 parts by mass, more preferably 60 to 100 parts by mass, and even more preferably 70 to 100 parts by mass, per 100 parts by mass of the polymerizable monomer (A). In addition, in an embodiment in which the dental curable composition of the present invention does not contain a polymerizable monomer (A-1) having an acidic group, the content of the hydrophobic polymerizable monomer (A-2a) in the dental curable composition is, from the viewpoint of the mechanical strength and operability of the cured product, preferably 45 mass % or less, more preferably 40 mass % or less, even more preferably 35 mass % or less, and particularly preferably 30 mass % or less, based on the total amount (100 mass %) of the dental curable composition.

[0040] Hydrophilic polymerizable monomers without acidic groups (A-2b) In the dental curable composition of the present invention, the polymerizable monomer (A) preferably contains a hydrophilic polymerizable monomer (A-2b) having no acidic group (hereinafter, sometimes simply referred to as "hydrophilic polymerizable monomer (A-2b)"). The hydrophilic polymerizable monomer (A-2b) improves the wettability of the dental curable composition to tooth structure. As the hydrophilic polymerizable monomer (A-2b), a radical polymerizable monomer having no acidic group and a polymerizable group is preferred, and from the viewpoint of easy radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophilic polymerizable monomer (A-2b) means a monomer having no acidic group and a solubility in water at 25°C of 10% by mass or more, preferably a monomer having a solubility of 30% by mass or more, and more preferably a monomer that can be dissolved in water at any ratio at 25°C. As the hydrophilic polymerizable monomer, a monomer having a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxypropylene group, or an amide group is preferred. Examples of the hydrophilic polymerizable monomer (A-2b) include hydrophilic monofunctional (meth)acrylate 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 polyethylene glycol di(meth)acrylate (number of oxyethylene groups: 9 or more); Examples of the hydrophilic monofunctional (meth)acrylamide polymerizable monomers include 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, and N,N-diethylacrylamide.

[0041] Among these hydrophilic polymerizable monomers (A-2b), from the viewpoint of adhesion to tooth structure, 2-hydroxyethyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and hydrophilic monofunctional (meth)acrylamide-based polymerizable monomers are preferred, and 2-hydroxyethyl (meth)acrylate, N,N-dimethylacrylamide, and N,N-diethylacrylamide are more preferred. The hydrophilic polymerizable monomer (A-2b) may be used alone or in combination of two or more kinds.

[0042] The content of the hydrophilic polymerizable monomer (A-2b) in the dental curable composition of the present invention is preferably in the range of 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, and even more preferably 0 to 30 parts by mass, in 100 parts by mass of the polymerizable monomer (A). The content of the hydrophilic polymerizable monomer (A-2b) may be 0 parts by mass in 100 parts by mass of the polymerizable monomer (A). When the content of the hydrophilic polymerizable monomer (A-2b) is within the above range, an effect of improving adhesion is obtained, and the cured product has a desired mechanical strength.

[0043] The content of the polymerizable monomer (A-2) having no acidic group is preferably 50 to 99 parts by mass, more preferably 60 to 97 parts by mass, and further preferably 70 to 95 parts by mass, in 100 parts by mass of the polymerizable monomer (A). In addition, in an embodiment in which the dental curable composition of the present invention does not contain a polymerizable monomer (A-1) having an acidic group, the content of the polymerizable monomer (A-2) not having an acidic group in the dental curable composition is, from the viewpoint of the mechanical strength and operability of the cured product, preferably 45 mass % or less, more preferably 40 mass % or less, even more preferably 35 mass % or less, and particularly preferably 30 mass % or less, based on the total amount (100 mass %) of the dental curable composition.

[0044] <Polymerization initiator (B)> The polymerization initiator (B) is classified into a water-soluble photopolymerization initiator (B-1), a water-insoluble photopolymerization initiator (B-2), and a chemical polymerization initiator (B-3). As the polymerization initiator (B), only the water-soluble photopolymerization initiator (B-1) may be used, only the water-insoluble photopolymerization initiator (B-2) may be used, or only the chemical polymerization initiator (B-3) may be used, or the water-soluble photopolymerization initiator (B-1), the water-insoluble photopolymerization initiator (B-2), and the chemical polymerization initiator (B-3) may be used in combination.

[0045] Water-soluble photopolymerization initiator (B-1) The water-soluble photopolymerization initiator (B-1) improves the polymerization curing property at the hydrophilic tooth surface interface, and can realize high adhesive strength. The water-soluble photopolymerization initiator (B-1) has a solubility in water at 25° C. of 10 g / L or more, preferably 15 g / L or more, more preferably 20 g / L or more, and even more preferably 25 g / L or more. When the solubility is 10 g / L or more, the water-soluble photopolymerization initiator (B-1) is sufficiently dissolved in the water in the tooth substance at the adhesive interface, and the polymerization promotion effect is easily exhibited.

[0046] Examples of the water-soluble photopolymerization initiator (B-1) include water-soluble acylphosphine oxides; water-soluble thioxanthones; 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one having a (poly)ethylene glycol chain introduced to the hydroxyl group, 1-hydroxycyclohexyl phenyl ketone having a (poly)ethylene glycol chain introduced to the hydroxyl group and / or phenyl group, and 1-hydroxycyclohexyl phenyl ketone having a -OCHCOO - Na + a (poly)ethylene glycol chain is introduced to the hydroxyl group and / or phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one; a -OCH2COO is introduced to the phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one - Na + and α-hydroxyalkylacetophenones such as those into which the above-mentioned formula has been introduced; and α-aminoalkylphenones such as 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one and 2-benzyl-2-(dimethylamino)-1-[(4-morpholino)phenyl]-1-butanone have been converted into quaternary ammonium salts.

[0047] Examples of the water-soluble thioxanthones include 2-hydroxy-3-(9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1-methyl-9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2- Hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(3,4-dimethyl-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1,3,4-trimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, and the like can be used.

[0048] Examples of the water-soluble acylphosphine oxides include acylphosphine oxides represented by the following general formula (2) or (3).

[0049] [ka]

[0050] [ka]

[0051] In the formula, A 1 , A 2 , A 3 , A 4 , A 5 , and A 6 are each independently a C1 to C4 linear or branched alkyl group or a halogen atom, and M is a hydrogen ion, an alkali metal ion, an alkaline earth metal ion, a magnesium ion, a pyridinium ion (the pyridine ring may have a substituent), or HN+ A 8 A 9 A 10 (In the formula, A 8 , A 9 , and A 10 are each independently an organic group or a hydrogen atom), n is 1 or 2, Z is a C1-C4 linear or branched alkylene group, and A 7 -CH(CH3)COO(C2H4O) p It is represented by CH3, and p represents an integer of 1 to 1000.

[0052] A 1 , A 2 , A 3 , A 4 , A 5 , and A 6 The alkyl group is not particularly limited as long as it is a C1 to C4 linear or branched alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a 2-methylpropyl group, and a tert-butyl group. A 1 , A 2 , A 3 , A 4 , A 5 , and A 6 The alkyl group is preferably a C1 to C3 linear alkyl group, more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkylene group represented by Z include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, and an n-butylene group. The alkylene group of Z is preferably a C1 to C3 linear alkylene group, more preferably a methylene group or an ethylene group, and further preferably a methylene group.

[0053] When M is a pyridinium ion, examples of the substituent on the pyridine ring include a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a carboxyl group, a C2 to C6 linear or branched acyl group, a C1 to C6 linear or branched alkyl group, and a C1 to C6 linear or branched alkoxy group. M is an alkali metal ion, an alkaline earth metal ion, a magnesium ion, a pyridinium ion (the pyridine ring may have a substituent), or HN + A 8 A 9 A 10 Preferred is an ammonium ion represented by the formula: (wherein the symbols have the same meanings as above). Examples of the alkali metal ion include a lithium ion, a sodium ion, a potassium ion, a rubidium ion, and a cesium ion. Examples of the alkaline earth metal ions include calcium ions, strontium ions, barium ions, and radium ions. A 8 , A 9 , and A 10 Examples of the organic group include the same as the substituents on the pyridine ring (excluding halogen atoms).

[0054] Among these, A 1 , A 2 , A 3 , A 4 , A 5 , and A 6 A compound in which all of are methyl groups is particularly preferred from the standpoint of storage stability and color stability in the composition. On the other hand, M n+ An example of this is Li + , Na + , K + , Ca 2+ , Mg 2+ and ammonium ions derived from various amines. Examples of the amines include ammonia, trimethylamine, diethylamine, dimethylaniline, ethylenediamine, triethanolamine, N,N-dimethylamino methacrylate, 4-(N,N-dimethylamino)benzoic acid and its alkyl esters, 4-(N,N-diethylamino)benzoic acid and its alkyl esters, and N,N-bis(2-hydroxyethyl)-p-toluidine. A 7In the above formula, from the viewpoint of adhesiveness, p is 1 or more, preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more. 7 In view of adhesion, p is 1000 or less, preferably 100 or less, more preferably 75 or less, and even more preferably 50 or less.

[0055] Among these water-soluble acylphosphine oxides, M n+ Li + A compound represented by general formula (2), 7 In particular, a compound synthesized from polyethylene glycol methyl ether methacrylate having a molecular weight of 950 corresponding to the group represented by the formula (2) is preferred. 1 , A 2 , and A 3 and A in general formula (3) 1 , A 2 , A 3 , A 4 , A 5 , and A 6 is as described above.

[0056] The water-soluble acylphosphine oxides having such a structure can be synthesized according to known methods, and some of them are also available as commercial products. For example, they can be synthesized by the methods disclosed in JP-A-57-197289 and WO 2014 / 095724. The water-soluble photopolymerization initiator (B-1) may be used alone or in combination of two or more.

[0057] The water-soluble photopolymerization initiator (B-1) may be dissolved in the dental hardenable composition or may be dispersed in the composition in the form of a powder.

[0058] When the water-soluble photopolymerization initiator (B-1) is dispersed in the composition in the form of a powder, if the average particle size is too large, it is likely to settle, so it is preferably 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. On the other hand, if the average particle size is too small, the specific surface area of ​​the powder becomes too large, and the amount dispersible in the composition decreases, so it is preferably 0.01 μm or more. That is, the average particle size of the water-soluble photopolymerization initiator (B-1) is preferably in the range of 0.01 to 500 μm, more preferably in the range of 0.01 to 100 μm, and even more preferably in the range of 0.01 to 50 μm.

[0059] The average particle size of each water-soluble photopolymerization initiator (B-1) powder can be calculated as the volume average particle size after performing image analysis using image analysis type particle size distribution measurement software (Mac-View; manufactured by Mountec Co., Ltd.) based on electron microscope photographs of 100 or more particles.

[0060] When the water-soluble photopolymerization initiator (B-1) is dispersed in the composition in the form of powder, the shape of the initiator may be, but is not particularly limited to, various shapes such as spherical, needle-like, plate-like, crushed, etc. The water-soluble photopolymerization initiator (B-1) can be prepared by a conventionally known method such as a pulverization method, a freeze-drying method, or a reprecipitation method, and from the viewpoint of the average particle size of the obtained powder, the freeze-drying method and the reprecipitation method are preferred, and the freeze-drying method is more preferred.

[0061] The content of the water-soluble photopolymerization initiator (B-1) is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the polymerizable monomer (A) in the dental curable composition of the present invention from the viewpoint of the curability of the dental curable composition obtained, and more preferably 0.05 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass from the viewpoint of adhesion to tooth structure. When the content of the water-soluble photopolymerization initiator (B-1) is 0.01 parts by mass or more, polymerization at the adhesive interface proceeds sufficiently, and the desired adhesiveness is obtained. On the other hand, when the content of the water-soluble photopolymerization initiator (B-1) is 20 parts by mass or less, sufficient adhesiveness is obtained.

[0062] · Non-water-soluble photopolymerization initiator (B-2) From the viewpoint of curability, the dental curable composition of the present invention preferably contains, in addition to the water-soluble photopolymerization initiator (B-1), a water-insoluble photopolymerization initiator (B-2) having a solubility in water at 25°C of less than 10 g / L (hereinafter, sometimes referred to as the water-insoluble photopolymerization initiator (B-2)). As the water-insoluble photopolymerization initiator (B-2) used in the present invention, a known photopolymerization initiator can be used. The water-insoluble photopolymerization initiator (B-2) may be used alone or in combination of two or more kinds.

[0063] Examples of the non-water-soluble photopolymerization initiator (B-2) include (bis)acylphosphine oxides, thioxanthones, ketals, α-diketones, coumarins, anthraquinones, benzoin alkyl ether compounds, and α-aminoketone compounds other than the water-soluble photopolymerization initiator (B-1).

[0064] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, and benzoyldi(2,6-dimethylphenyl)phosphonate. Examples of the bisacylphosphine oxides include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0065] Examples of the thioxanthones include thioxanthone, 2-chlorothioxanthen-9-one, and the like.

[0066] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0067] Examples of the α-diketones include diacetyl, benzil, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzil, acenaphthenequinone, etc. Among these, dl-camphorquinone is particularly preferred from the viewpoint of having a maximum absorption wavelength in the visible light region.

[0068] Examples of the coumarins include 3,3'-carbonylbis(7-diethylaminocoumarin), 3-(4-methoxybenzoyl)coumarin, 3-thienoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin, 3-benzoylcoumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin), 3-benzoyl-6-bromo Coumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin, 3-carboxycoumarin, 3-carboxy-7-methoxycoumarin, 3-ethoxycarbonyl-6-methoxycoumarin, 3-ethoxycarbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin, 3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-methoxybenzoyl)coumarin )coumarin, 7-diethylamino-3-(4-diethylamino)coumarin, 7-methoxy-3-(4-methoxybenzoyl)coumarin, 3-(4-nitrobenzoyl)benzo[f]coumarin, 3-(4-ethoxycinnamoyl)-7-methoxycoumarin, 3-(4-dimethylaminocinnamoyl)coumarin, 3-(4-diphenylaminocinnamoyl)coumarin, 3-[(3-dimethylbenzothiazol-2-ylidene)acetyl]coumarin, 3-[(1-methylnaphtho[1,2-d]thiazol-2-ylidene)acetyl]coumarin, 3,3'-carbo nylbis(6-methoxycoumarin), 3,3'-carbonylbis(7-acetoxycoumarin), 3,3'-carbonylbis(7-dimethylaminocoumarin), 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dibutylamino)coumarin, 3-(2-benzimidazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dioctylamino)coumarin, 3-acetyl-7-(dimethylamino)coumarin, 3,3'-carbonylbis(7-dibutylamino)coumarin, 3,Examples of the compounds include those described in JP-A-9-3109 and JP-A-10-245525, such as 3'-carbonyl-7-diethylaminocoumarin-7'-bis(butoxyethyl)aminocoumarin, 10-[3-[4-(dimethylamino)phenyl]-1-oxo-2-propenyl]-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one, and 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one.

[0069] Among the above-mentioned coumarins, 3,3'-carbonylbis(7-diethylaminocoumarin) and 3,3'-carbonylbis(7-dibutylaminocoumarin) are particularly preferred.

[0070] Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benzanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-hydroxyanthraquinone.

[0071] Examples of the benzoin alkyl ether compound include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

[0072] Examples of the α-aminoketone compounds include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.

[0073] Among these water-insoluble photopolymerization initiators (B-2), it is preferable to use at least one selected from the group consisting of (bis)acylphosphine oxides, α-diketones, and coumarins, which provides a dental curable composition that is excellent in photocurability in the visible and near-ultraviolet regions and exhibits sufficient photocurability using any of the light sources, such as a halogen lamp, a light-emitting diode (LED), and a xenon lamp.

[0074] The content of the water-insoluble photopolymerization initiator (B-2) is not particularly limited, but from the viewpoint of the curability of the obtained dental curable composition, it is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the polymerizable monomer (A) in the dental curable composition of the present invention. When the content of the water-insoluble photopolymerization initiator (B-2) is 10 parts by mass or less, the curability is good, the polishability is excellent, and sufficient mechanical strength is obtained.

[0075] When the water-soluble photopolymerization initiator (B-1) and the water-insoluble photopolymerization initiator (B-2) are used in combination, the mass ratio of the water-soluble photopolymerization initiator (B-1) to the water-insoluble photopolymerization initiator (B-2) in the present invention [(B-1):(B-2)] is preferably 10:1 to 1:10, more preferably 7:1 to 1:7, even more preferably 5:1 to 1:5, and most preferably 3:1 to 1:3. If the water-soluble photopolymerization initiator (B-1) is contained in a mass ratio of more than 10:1, the hardening property of the dental hardening composition itself decreases, and the polishing property also decreases, so that it may be difficult to develop high mechanical strength. On the other hand, if the water-insoluble photopolymerization initiator (B-2) is contained in a mass ratio of more than 1:10, the hardening property of the dental hardening composition itself is enhanced, but the polymerization promotion at the adhesive interface becomes insufficient, so that it may be difficult to develop high mechanical strength and polishing property.

[0076] Chemical polymerization initiator (B-3) The dental curable composition of the present invention can contain a chemical polymerization initiator (B-3), and an organic peroxide is preferably used. The organic peroxide used in the above-mentioned chemical polymerization initiator is not particularly limited, and known organic peroxides can be used. Representative organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, peroxydicarbonates, etc. Specific examples of these organic peroxides include those described in WO 2008 / 087977.

[0077] Examples of the ketone peroxide include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, methylcyclohexanone peroxide, and cyclohexanone peroxide.

[0078] Examples of the hydroperoxide include 2,5-dimethylhexane-2,5-dihydroperoxide, diisopropylbenzene hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide.

[0079] Examples of the diacyl peroxide include acetyl peroxide, isobutyryl peroxide, benzoyl peroxide, decanoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, 2,4-dichlorobenzoyl peroxide, and lauroyl peroxide.

[0080] Examples of the dialkyl peroxide include di-t-butyl peroxide, dicumyl peroxide, t-butylcumyl peroxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 1,3-bis(t-butylperoxyisopropyl)benzene, and 2,5-dimethyl-2,5-di(t-butylperoxy)-3-hexyne.

[0081] Examples of the peroxyketals include 1,1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, and 4,4-bis(t-butylperoxy)valeric acid-n-butyl ester.

[0082] Examples of the peroxy ester include α-cumyl peroxy neodecanoate, t-butyl peroxy neodecanoate, t-butyl peroxy pivalate, 2,2,4-trimethylpentyl peroxy-2-ethylhexanoate, t-amyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, di-t-butyl peroxy isophthalate, di-t-butyl peroxy hexahydroterephthalate, t-butyl peroxy-3,3,5-trimethylhexanoate, t-butyl peroxy acetate, t-butyl peroxy benzoate, and t-butyl peroxy maleic acid.

[0083] Examples of the peroxydicarbonate include di(3-methoxybutyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, bis(4-t-butylcyclohexyl)peroxydicarbonate, diisopropylperoxydicarbonate, di-n-propylperoxydicarbonate, di(2-ethoxyethyl)peroxydicarbonate, and diallylperoxydicarbonate.

[0084] Among these organic peroxides, diacyl peroxides are preferably used from the viewpoint of the overall balance of safety, storage stability, and radical generating ability, and among them, benzoyl peroxide is more preferably used.

[0085] The chemical polymerization initiator (B-3) may be used alone or in combination of two or more kinds. The dental curable composition of the present invention may be a dual-cure type dental curable composition using a water-soluble photopolymerization initiator (B-1) and / or a water-insoluble photopolymerization initiator (B-2) in combination with a chemical polymerization initiator (B-3).

[0086] <Dental inorganic aggregate filler (C)> The dental inorganic aggregate filler (C) simultaneously satisfies the following (c1), (c2), and (c3): (c1) The primary particles constituting the inorganic agglomerated filler have an irregular shape (except for a spherical shape). (c2) The average particle size of the primary particles constituting the inorganic aggregate filler is 650 nm or less. (c3) The inorganic aggregate filler has a microcompression hardness of 10 to 300 MPa.

[0087] Regarding (c1), the primary particles constituting the inorganic aggregate filler (C) have an irregular shape (except for a spherical shape). The crushed shape obtained by pulverization provides the cured product with excellent mechanical strength. As used herein, "irregular" means that the particle has a shape that is irregular and has many corners and faces. "Irregular" particles do not include spherical particles. In this specification, a filler being "spherical" means that when a photograph of the filler is taken with a scanning electron microscope (hereinafter abbreviated as "SEM"), the particles observed within a unit field of view are rounded, and the average uniformity obtained by dividing the particle diameter in a direction perpendicular to the maximum diameter by the maximum diameter is 0.6 or more. The primary particles constituting the inorganic agglomerated filler (C) are usually in a crushed form obtained by a crushing or grinding process. If the primary particles constituting the inorganic agglomerated filler (C) are spherical, the desired mechanical strength of the cured product cannot be obtained.

[0088] Regarding (c2), the average particle size of the primary particles constituting the inorganic aggregate filler (C) is 650 nm or less, preferably 600 nm or less, and from the viewpoint of superior polishing properties and better paste properties, more preferably 500 nm or less, even more preferably 450 nm or less, and particularly preferably 400 nm or less. In addition, the average particle size of the primary particles constituting the inorganic aggregate filler (C) is preferably 1 nm or more, and from the viewpoint of superior polishability, is more preferably 5 nm or more, even more preferably 10 nm or more, and particularly preferably 30 nm or more.

[0089] In this specification, the average particle size of primary particles (hereinafter also referred to as "average primary particle size") can be determined by a laser diffraction scattering method or by observing particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, while electron microscope observation is convenient for measuring the particle sizes of ultrafine particles less than 0.1 μm. 0.1 μm is a value measured by the laser diffraction scattering method. In the laser diffraction scattering method, for example, a 0.2% aqueous solution of sodium hexametaphosphate can be used as a dispersion medium and the measurement can be performed on a volume basis with a laser diffraction particle size distribution measuring device (SALD-2300, manufactured by Shimadzu Corporation). For electron microscope observation, a scanning electron microscope (SU3900, Hitachi High-Technologies Corporation, etc.) can be used. Electron microscope observation can be performed by taking an electron microscope photograph of the particles and measuring the particle size of the particles (200 or more) observed within a unit field of view of the photograph using image analysis particle size distribution measurement software (Mac-View, Mountec Corporation). In this case, the particle size is calculated as the arithmetic mean value of the longest and shortest lengths of the particles, and the average primary particle size is calculated from the number of particles and their particle size.

[0090] Regarding (c3), the microcompression hardness of the inorganic aggregate filler (C) is 10 to 300 MPa, and from the viewpoint of superior polishability and better paste properties, it is preferably 200 MPa or less, more preferably 150 MPa or less, even more preferably 90 MPa or less, particularly preferably 80 MPa or less, and most preferably 75 MPa or less. The microcompression hardness of the inorganic aggregate filler (C) is preferably 12 MPa or more, more preferably 15 MPa or more, even more preferably 18 MPa or more, and particularly preferably 20 MPa or more, in terms of better paste properties.

[0091] The inorganic agglomerated filler (C) is preferably surface-treated with a binder to have a desired range of microcompression hardness. A method for producing the inorganic agglomerated filler (C) is described below.

[0092] <Method for producing inorganic aggregate filler (C)> Examples of a method for producing the inorganic agglomerated filler (C) include a method for producing an inorganic agglomerated filler, which includes a mixing step of mixing a dispersion obtained by dispersing inorganic particles having an average primary particle size of 650 nm or less in a solvent with a binder containing at least one metal oxide selected from the group consisting of silicon, barium, aluminum and transition metal elements of Groups 3 to 11 to obtain a mixed liquid, a drying step of drying the mixed liquid to obtain a dried body, and a firing step of firing the dried body.

[0093] ·Mixing process In the mixing step, a dispersion liquid obtained by dispersing inorganic particles in a solvent and a binder containing a metal oxide are mixed to obtain a mixed liquid.

[0094] Examples of the inorganic particle material of the primary particles constituting the inorganic aggregate filler (C) include quartz, silica, alumina, composite oxides (e.g., silica-titania-barium oxide, silica-zirconia, silica-titania, silica-alumina, silica-alumina-zirconia), various glasses (containing silica as the main component and, as necessary, oxides of heavy metals, boron, zirconium, titanium, aluminum, etc.; e.g., fused silica, lanthanum glass, borosilicate glass, soda glass, strontium glass, glass ceramics, etc.). glass, aluminosilicate glass, strontium boroaluminosilicate glass, fluoroaluminosilicate glass, calcium fluoroaluminosilicate glass, strontium fluoroaluminosilicate glass, strontium calcium fluoroaluminosilicate glass, barium glass (barium silicate glass, barium boroaluminosilicate glass, barium fluoroaluminosilicate glass, etc.), ytterbium oxide, and silica-coated ytterbium fluoride. Among these, in terms of excellent mechanical strength and transparency of the cured product, quartz, silica, silica-zirconia composite oxide, barium glass, ytterbium oxide, and silica-coated ytterbium fluoride are preferred, and quartz, silica, silica-zirconia composite oxide, barium glass, and silica-coated ytterbium fluoride are more preferred.

[0095] As the inorganic primary particles, commercially available products may be used. Examples of commercially available products include silica such as Aerosil (registered trademark) 90, Aerosil (registered trademark) 130, Aerosil (registered trademark) 150, Aerosil (registered trademark) 200, Aerosil (registered trademark) 255, Aerosil (registered trademark) 300, Aerosil (registered trademark) 380, Aerosil (registered trademark) OX50, and Aerosil (registered trademark) R972 (all manufactured by Nippon Aerosil Co., Ltd.), GM27884, 8235 (all manufactured by SCHOTT), barium glass such as product code "E-3000" (manufactured by Estech), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by Schott), and fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by Schott).

[0096] The solvent includes water and organic solvents. Examples of organic solvents include alcohol solvents such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-methyl-2-propanol; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran, diethyl ether, and diisopropyl ether; non-aromatic hydrocarbon solvents such as hexane and cyclohexane; aromatic hydrocarbon solvents such as toluene; chlorine-based solvents such as chloroform; and ester solvents such as ethyl acetate and butyl acetate. The solvent may be used alone or in combination of two or more kinds.

[0097] The inorganic particles are dispersed in a solvent to obtain a dispersion liquid. The method of dispersion is not particularly limited, and known methods can be used. For example, stirring of the inorganic particles in a solvent, ultrasonic dispersion treatment, nano dispersion treatment, etc. can be mentioned. For ultrasonic dispersion treatment, nano-dispersion treatment, and the like, a known dispersion treatment device can be used. In order to thoroughly disperse the primary particles, ultrasonic dispersion treatment and nano-dispersion treatment may be combined. Although thorough dispersion is preferable in order to enhance the effect of the surface treatment with a binder in the subsequent step, the method of dispersion treatment is not limited as long as thorough dispersion can be achieved by, for example, extending the ultrasonic dispersion treatment time. The inorganic particles to be dispersed in the solvent may be subjected to a pulverization process and / or a classification process, if necessary, to adjust the average particle size to fall within a predetermined range. The form of the dispersion is not particularly limited, and may be a slurry depending on the proportion of inorganic particles, etc.

[0098] The dispersion liquid is mixed with a binder containing a metal oxide to obtain a mixed liquid. The metal oxide may be at least one metal oxide selected from the group consisting of silicon, barium, aluminum, and transition metal elements of Groups 3 to 11. Silicon, aluminum, and zirconium are preferred because they can firmly bond primary particles together via metal atoms contained in the metal oxide and the inorganic aggregate filler (C) can be easily adjusted to have a desired microcompression hardness. The metal oxides may be used alone or in combination of two or more.

[0099] The binder containing the metal oxide may be a binder represented by the following general formula (1): R 1 n SiY 4-n (1) (In the formula, R 1 represents a substituted or unsubstituted hydrocarbon group having 1 to 25 carbon atoms, Y represents an alkoxy group having 1 to 4 carbon atoms, an acyloxy group having 1 to 5 carbon atoms, a hydroxy group, a halogen atom, or a hydrogen atom, and n is an integer of 0 to 3, with the proviso that R 1 When there are multiple X's, they may be the same or different. A silane coupling agent represented by the following formula is preferred.

[0100] R 1The hydrocarbon group has 1 to 25 carbon atoms, preferably 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and further preferably 1 to 12 carbon atoms.

[0101] R 1 The hydrocarbon group may be either linear or branched. R 1 The hydrocarbon group is preferably a polymerizable group or a monovalent organic group having a polymerizable group. The type of the polymerizable group is not particularly limited, and examples thereof include a (meth)acryloyl group, a vinyl group, a mercapto group, a (meth)allyl group, an epoxy group, etc. Among these, from the viewpoint of mechanical strength, etc., a (meth)acryloyl group is preferred, and a methacryloyl group is more preferred.

[0102] R 1 When the hydrocarbon group is a monovalent organic group having a polymerizable group, the polymerizable group may be directly bonded to the monovalent organic group, or may be bonded via a divalent group containing a heteroatom such as an oxygen atom or a nitrogen atom. That is, the (meth)acryloyl group may form a (meth)acryloyloxy group or a (meth)acrylamide group.

[0103] R 1 The number of polymerizable groups that R has is not particularly limited, but is preferably 1 to 4, more preferably 1 or 2, and even more preferably 1. 1 When has multiple polymerizable groups, they may be the same or different.

[0104] R 1 may be formed only from the polymerizable group, or may be formed by bonding the functional group and the organic group directly or indirectly via a divalent group containing a heteroatom such as an oxygen atom or a nitrogen atom. The organic group is not particularly limited, and examples thereof include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 18 carbon atoms, and an aralkyl group having 7 to 26 carbon atoms. Among these, alkyl groups having 1 to 20 carbon atoms are preferred, alkyl groups having 1 to 12 carbon atoms are more preferred, and alkyl groups having 3 to 11 carbon atoms are even more preferred, from the viewpoint of being able to firmly bond the primary particles together so that the inorganic aggregate filler (C) has the desired microcompression hardness after dehydration condensation by firing. Examples of the alkyl group having 3 to 11 carbon atoms include an n-propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, an n-octyl group, and an n-undecyl group. An n-propyl group, an n-pentyl group, an n-octyl group, and an n-undecyl group are preferred, and an n-propyl group, an n-octyl group, and an n-undecyl group are more preferred.

[0105] R 1 Specific examples of the aryl group include a (meth)acryloyloxymethyl group, a 3-(meth)acryloyloxypropyl group, a 3-(meth)acrylamidopropyl group, a vinyl group, a (meth)allyl group, and a 3-glycidoxypropyl group. Of these, a (meth)acryloyloxymethyl group, a 3-(meth)acryloyloxypropyl group, a 3-(meth)acryloyloxyoctyl group, and a 3-(meth)acryloyloxyundecyl group are preferred, and a 3-(meth)acryloyloxypropyl group, an 8-(meth)acryloyloxyoctyl group, and an 11-(meth)acryloyloxyundecyl group are more preferred.

[0106] The alkoxy group having 1 to 4 carbon atoms represented by Y may be either linear or branched. Examples of the alkoxy group having 1 to 4 carbon atoms for Y include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, and an n-butoxy group.

[0107] The acyloxy group having 1 to 5 carbon atoms represented by Y may be either linear or branched. Examples of the acyloxy group having 1 to 5 carbon atoms for Y include a formyloxy group, an acetoxy group, an n-propionyloxy group, an isopropionyloxy group, an n-butanoyloxy group, and an n-pentanoyloxy group.

[0108] Examples of the halogen atom represented by Y include a chlorine atom, a bromine atom, and a fluorine atom.

[0109] Among these, Y is preferably an alkoxy group, more preferably an alkoxy group having 1 to 5 carbon atoms, and further preferably a methoxy group or an ethoxy group.

[0110] n is an integer of 0 to 3, and is preferably an integer of 0, 1 or 2, and more preferably 0 or 1, from the viewpoint of the mechanical strength of the cured product. In addition, when n is 0 or 1, the multiple Y's may be the same or different. When n is 2, the multiple R 1 may be the same or different from each other.

[0111] Specific examples of the silane coupling agent include (meth)acryloyloxymethyltrimethoxysilane, 2-(meth)acryloyloxyethyltrimethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 4-(meth)acryloyloxybutyltrimethoxysilane, 5-(meth)acryloyloxypentyltrimethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, 7-(meth)acryloyloxyheptyltrimethoxysilane, and 8-(meth)acryloyloxyoctyltrimethoxysilane. , 9-(meth)acryloyloxynonyltrimethoxysilane, 10-(meth)acryloyloxydecyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, 11-(meth)acryloyloxyundecyldichloromethylsilane, 11-(meth)acryloyloxyundecyltrichlorosilane, 11-(meth)acryloyloxyundecyldimethoxymethylsilane, 12-(meth)acryloyloxydodecyltrimethoxysilane, 13-(meth)acryloyloxytridecyltrimethoxysilane, 3-(meth)acryloyloxytridecyltrimethoxysilane, Meth)acryloyloxypropyl methyldimethoxysilane, 3-(meth)acryloyloxypropyl methyldiethoxysilane, 3-(meth)acryloyloxypropyl methyldiisopropoxysilane, 3-(meth)acryloyloxypropyl methyldimethylsiloxysilane, 3-(meth)acryloyloxypropyl methyldihexyloxysilane, (meth)acryloyloxy-2-(2-vinyloxyethoxy)ethylmethyldimethoxysilane, 6-(meth)acryloyloxyhexylmethyldimethoxysilane, (meth)acryloyloxy- p-phenylethylmethyldimethoxysilane, 6-(meth)acryloyloxyhexylmethyldiethoxysilane, 10-(meth)acryloyloxydecylmethyldimethoxysilane, 11-(meth)acryloyloxyundecylmethyldimethoxysilane, 11-(meth)acryloyloxyundecylmethyldiethoxysilane, 11-(meth)acryloyloxyundecylmethyldihexyloxysilane, 20-(meth)acryloyloxyeicosylmethyldimethoxysilane, 3-(meth)acryloyloxypropylphenyldimethoxysilane,3-(meth)acryloyloxypropylmethyldichlorosilane, 11-(meth)acryloyloxyundecylmethyldichlorosilane, 11-(meth)acryloyloxyundecylethyldichlorosilane, 3-(meth)acryloyloxypropyldimethylmonomethoxysilane, 3-(meth)acryloyloxypropyldimethylmonoethoxysilane, 3-(meth)acryloyloxypropyldimethylmonoisopropoxysilane, 3-(meth)acryloyloxypropyldimethylmonotrimethylsiloxysilane, 3-(meth)acryloyloxypropyldimethylmonotrimethylsiloxysilane Dipropyl dimethyl monohexyloxy silane, (meth)acryloyloxy-2-(2-vinyloxyethoxy)ethyl dimethyl monomethoxy silane, 6-(meth)acryloyloxyhexyl dimethyl monomethoxy silane, (meth)acryloyloxy-p-phenylethyl dimethyl monomethoxy silane, 6-(meth)acryloyloxyhexyl dimethyl monoethoxy silane, 10-(meth)acryloyloxydecyl dimethyl monomethoxy silane, 11-(meth)acryloyloxyundecyl dimethyl monomethoxy silane, 11-(meth)acryloyloxydecyl dimethyl monomethoxy silane, (meth)acryloyl group-containing silanes such as 11-(meth)acryloyloxyundecyldimethylmonoethoxysilane, 11-(meth)acryloyloxyundecyldimethylmonohexyloxysilane, 20-(meth)acryloyloxyeicosyldimethylmonomethoxysilane, 3-(meth)acryloyloxypropyldiphenylmonomethoxysilane, 3-(meth)acryloyloxypropyldimethylmonochlorosilane, 11-(meth)acryloyloxyundecyldimethylmonochlorosilane, and 11-(meth)acryloyloxyundecyldiethylmonochlorosilane. coupling agents; vinyl group-containing silane coupling agents such as vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldichlorosilane, vinylmethyldiacetoxysilane, vinylmethyldi(2-methoxyethoxy)silane, vinyldimethylmonomethoxysilane, vinyldimethylmonoethoxysilane, vinyldimethylmonochlorosilane, vinyldimethylmonoacetoxysilane, and vinyldimethylmono(2-methoxyethoxy)silane; 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane,Examples of the silane coupling agents include epoxy group-containing silane coupling agents such as 3-glycidoxypropyldimethylmonomethoxysilane and 3-glycidoxypropyldimethylmonoethoxysilane; and allyl group-containing silane coupling agents such as allylmethyldiethoxysilane and allyldimethylmonoethoxysilane. The silane coupling agent may be a product obtained by hydrolysis and / or condensation of these. The binder may be used alone or in combination of two or more kinds. Among these, from the viewpoints of the ability to firmly bond primary particles together so that the inorganic aggregate filler (C) has the desired microcompression hardness after dehydration condensation by firing, and mechanical strength, etc., 3-methacryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, and hydrolysates thereof are preferred.

[0112] In the mixing step, the amount of binder added relative to 100 parts by mass of inorganic particles is preferably 1 to 35 parts by mass, more preferably 1 to 28 parts by mass, and even more preferably 1 to 25 parts by mass, from the viewpoints that the binder can firmly bind the primary particles together so that the inorganic agglomerated filler (C) has a desired microcompression hardness after dehydration and condensation by firing, and that it is easier to control the secondary particle diameter.

[0113] In the mixing step, from the viewpoints of increasing reactive sites, removing polyvalent metals, and enhancing storage stability, a treatment with an acid (hereinafter sometimes simply referred to as "acid treatment") may be carried out before the surface treatment. The acid treatment may be carried out after the mixing step, or may be carried out simultaneously with mixing with the binder.

[0114] The acid used in the acid treatment is not particularly limited, and may be either an organic acid or an inorganic acid. Inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, sulfonic acid, etc. Organic acids include formic acid, acetic acid, propionic acid, oxalic acid, citric acid, tartaric acid, etc. The method of the acid treatment is not particularly limited as long as it is a method that brings the filler into contact with the acid. For example, a method in which the filler is stirred in an acidic aqueous solution is preferred.

[0115] The concentration of the acidic aqueous solution used in the acid treatment is preferably from 0.1 to 20% by mass, more preferably from 1 to 10% by mass. The amount of the acidic aqueous solution having the above concentration to be used is preferably 10 to 1000 parts by mass with respect to 100 parts by mass of the filler.

[0116] ·Drying process In the drying step, the mixture obtained in the mixing step is dried to obtain a dry product. There is no particular limitation on the drying method, and for example, spray drying, supercritical drying, freeze drying, hot air drying, reduced pressure drying, etc. can be used. Among these, any of spray drying, supercritical drying, and freeze drying is preferred, any of spray drying and supercritical drying is more preferred, and spray drying is even more preferred, in terms of ease of uniformly controlling the particle size of the secondary particles during drying and ease of condensing the binder by heating.

[0117] · Firing process In the firing step, the dried body obtained in the drying step is fired. The firing temperature is preferably 600 to 800°C, more preferably 620 to 780°C, and even more preferably 650 to 750°C, from the viewpoints that the primary particles can be firmly bonded to each other via the metal atoms contained in the metal oxide and the inorganic aggregate filler (C) can be adjusted to have a desired microcompression hardness. The firing time is preferably 0.5 to 6 hours, more preferably 1 to 5 hours, and even more preferably 1.5 to 4.5 hours, from the viewpoints that the primary particles can be firmly bonded to each other via the metal atoms contained in the metal oxide and that the inorganic aggregate filler (C) can be adjusted to have the desired microcompression hardness.

[0118] In the firing step, the firing temperature is preferably 30 to 80% of the melting temperature of the primary particles or the melting point of the main component (the component having the largest mixing ratio) that forms the primary particles. For example, when the main component forming the primary particles is SiO2, the temperature is preferably within a range of 30 to 80% of the melting point temperature of SiO2, more preferably within a range of 35 to 75% of the melting point temperature, and even more preferably within a range of 40 to 70% of the melting point temperature.

[0119] The average particle size (average particle size of secondary particles) of the dental inorganic agglomerated filler (C) is preferably 2 to 20 μm, more preferably 4 to 18 μm, and even more preferably 5 to 15 μm, from the viewpoint of improving the properties of the paste and the mechanical strength of the cured product.

[0120] As an embodiment of the present invention, there are provided the following (c1), (c2) and (c3): (c1) The primary particles constituting the inorganic aggregate filler have an irregular shape (except for a spherical shape); (c2) the average particle size of the primary particles constituting the inorganic aggregate filler is 650 nm or less; (c3) The inorganic aggregate filler has a microcompression hardness of 10 to 300 MPa. and a dental inorganic aggregate filler (C) that satisfies the above requirements at the same time.

[0121] When used in a dental hardenable composition, the dental inorganic aggregate filler (C) can impart good paste properties and excellent mechanical strength and polishability to the hardened product.

[0122] The primary particles of the dental inorganic aggregate filler (C) are not spherical in shape, but the secondary particles are preferably spherical because the scattering of light caused by the surface irregularities is likely to be small when the particles fall off during polishing. However, the shape of the secondary particles may not be spherical depending on the drying method in the drying step. Even if the shape of the secondary particles is not spherical, the effect of the present invention can be achieved by the primary particles falling off within a desired range during polishing.

[0123] The dental inorganic aggregate filler (C) is preferably 5 to 50 mass %, more preferably 10 to 48 mass %, and even more preferably 15 to 45 mass %, of the total amount (100 mass %) of the dental hardenable composition, in order to provide excellent mechanical strength of the hardened product.

[0124] The specific surface area of ​​the inorganic aggregate filler (C) is set to 80m2 because it provides excellent mechanical strength of the hardened product and better paste properties. 2 / g or less, and 2 / g or less is more preferable, and 70m 2 It is more preferable that the molecular weight is not more than 1 / g. In addition, the specific surface area of ​​the inorganic aggregate filler (C) is set to 10 m because it has better paste properties. 2 / g or more, and 2 / g or more is more preferable, and 14m 2 The specific surface area of ​​the inorganic aggregate filler (C) is preferably 15 m / g or more for the purpose of adjusting the operability of the paste. 2 / g or more, 20m 2 / g or more.

[0125] The BET specific surface area of ​​the inorganic aggregate filler (C) can be determined by a specific surface area / pore distribution measuring device based on the gas adsorption method, and can be measured in accordance with the BET method described in JIS Z 8830:2013 or ISO 9277:2010. Specifically, after vacuum degassing at 100°C for 2 hours using a specific surface area measuring device (product name: BELSORP-mini-II, constant volume gas adsorption method (nitrogen adsorption / desorption measurement), manufactured by Microtrack-Bel Corporation), the surface area can be measured based on the BET method under the following conditions: adsorbed gas: nitrogen, measurement temperature: 77K.

[0126] <Non-agglomerated filler (D)> The dental hardenable composition of the present invention preferably contains a non-agglomerating filler (D) in addition to the inorganic agglomerating filler (C) in order to adjust the workability of the paste and to increase the mechanical strength of the hardened product. In addition, it is preferable that the dental hardenable composition of the present invention does not contain any agglomerated filler other than the agglomerated filler (C) in terms of paste properties, mechanical strength and polishability of the uncured product. The non-agglomerated filler (D) includes inorganic fillers, organic fillers, and organic-inorganic composite fillers. The non-aggregating filler (D) may be blended either alone or in combination of two or more kinds. The non-agglomerated filler (D) will be described below.

[0127] Examples of the organic filler material include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, cross-linked polymethyl methacrylate, cross-linked polyethyl methacrylate, polyamide, polyvinyl chloride, polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer, etc., which may be used alone or as a mixture of two or more. The shape of the organic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoints of the ease of handling and mechanical strength of the resulting dental curable composition, the average particle size of the organic filler is preferably from 0.001 to 50 μm, and more preferably from 0.001 to 10 μm.

[0128] The inorganic filler material may be various glasses (mainly composed of silica, and may contain oxides of heavy metals, boron, aluminum, etc., as required). 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 (GM27884, 8235, manufactured by SCHOTT, E-2000, E-3000, manufactured by ESSTECH), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by SCHOTT), and fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by SCHOTT), various ceramics, composite oxides such as silica-titania and silica-zirconia, diatomaceous earth, kaolin, clay minerals (montmorillonite, etc.), activated clay, synthetic zeolite, etc. Examples of the fluoride include light, 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 and having a surface coated with silica, ytterbium fluoride having a core-shell structure and having a surface coated with silica, yttrium fluoride having a core-shell structure and having a surface coated with silica, calcium phosphate having a core-shell structure and having a surface coated with silica, barium sulfate having a core-shell structure and having a surface coated with silica, zirconium dioxide having a core-shell structure and having a surface coated with silica, titanium dioxide having a core-shell structure and having a surface coated with silica, and hydroxyapatite having a core-shell structure and having a surface coated with silica are preferred. These may be used alone or in combination of two or more. In this specification, when the non-agglomerated filler (D) is subjected to a surface treatment, the average particle size of the non-agglomerated filler (D) means the average particle size before the surface treatment.

[0129] The shape of the inorganic filler includes irregular fillers and spherical fillers. From the viewpoint of improving the mechanical strength of the cured product of the dental curable composition, it is preferable to use a spherical filler as the inorganic filler. "Spherical" is as defined above. The average particle size of the inorganic filler is preferably 1 nm to 2000 nm, more preferably 5 nm to 1000 nm, and even more preferably 10 nm to 800 nm, from the viewpoints of the handling property, mechanical strength, and polishability of the dental curable composition when combined with the inorganic aggregate filler (C).

[0130] The organic-inorganic composite filler that may be used in the present invention is obtained by adding a polymerizable monomer to the inorganic filler described above in advance, forming a paste, polymerizing it, and pulverizing it. As the organic-inorganic composite filler, for example, TMPT filler (trimethylolpropane methacrylate and silica filler are mixed, polymerized, and then pulverized) can be used. The shape of the organic-inorganic composite filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoints of the ease of handling and mechanical strength of the resulting composition, the average particle size of the organic-inorganic composite filler is preferably from 0.001 to 50 μm, and more preferably from 0.001 to 10 μm. The average particle size of the inorganic filler constituting the organic-inorganic composite filler is preferably 650 nm or less, more preferably 600 nm or less, and from the viewpoint of superior polishing properties and better paste properties, is even more preferably 500 nm or less, particularly preferably 450 nm or less, and most preferably 400 nm or less.

[0131] In this specification, the average particle size of the non-aggregated filler (D) can be measured in the same manner as the average particle size of the primary particles constituting the inorganic aggregated filler (C).

[0132] In the dental hardenable composition of the present invention, it is preferable to use a combination of two or more types of fillers having different properties, average particle sizes, and / or shapes. By combining two or more types of fillers, the fillers are packed densely and the number of interaction points between the fillers and the polymerizable monomers or between the fillers themselves increases. In addition, the fluidity of the paste can be controlled by the presence or absence of shear force depending on the type of filler. The fillers of each particle size may contain different types of fillers. Furthermore, particles other than the filler may be unintentionally contained as impurities within a range that does not impair the effects of the present invention.

[0133] The non-aggregating filler (D) may be used after being surface-treated in advance with a known surface treatment agent such as a silane coupling agent, if necessary, in order to adjust the flowability of the dental hardenable composition. The silane coupling agent may be the silane coupling agent represented by the general formula (1) above.

[0134] From the viewpoint of excellent polishing properties, the content of the non-aggregating filler (D) is preferably from 5 to 45 mass %, more preferably from 10 to 40 mass %, and even more preferably from 15 to 40 mass %.

[0135] Polymerization accelerator In the dental curable composition of the present invention, a polymerization accelerator can be used together with the polymerization initiator (B). Examples of the polymerization accelerator used in the present invention include amines, sulfinic acid and its salts, borate compounds, barbituric acid compounds, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds. The polymerization accelerator may be used alone or in combination of two or more kinds.

[0136] The amines used as polymerization accelerators are divided into aliphatic amines and aromatic amines. Examples of the aliphatic amine 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, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, from the viewpoint of the hardening property and storage stability of the dental hardenable composition, tertiary aliphatic amines are preferred, and among them, N-methyldiethanolamine and triethanolamine are more preferably used.

[0137] Examples of aromatic amines include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis(2-hydroxyethyl)-4-ethylaniline, N,N-bis(2-hydroxyethyl)-4-isopropylaniline, N,N-bis(2-hydroxyethyl)-4-t-butylaniline, N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, and N,N-diethyl-p -toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, N,N-dimethyl-3,5-di-t-butylaniline, 4-(N,N-dimethylamino)ethyl benzoate, 4-(N,N-dimethylamino)methyl benzoate, 4-(N,N-dimethylamino)propyl benzoate, 4-(N,N-dimethylamino)n-butoxyethyl benzoate, 4-(N,N-dimethylamino)2-(methacryloyloxy)ethyl benzoate, 4-(N,N-dimethylamino)benzophenone, and 4-(N,N-dimethylamino)butyl benzoate. Among these, from the viewpoint of imparting excellent hardenability to the dental hardenable composition, at least one selected from the group consisting of N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone is preferably used.

[0138] Specific examples of sulfinic acids and salts thereof, borate compounds, barbituric acid compounds, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds include those described in WO 2008 / 087977.

[0139] The content of the polymerization accelerator used in the present invention is not particularly limited, but from the viewpoint of the curability of the obtained dental curable composition, the content is preferably 0.001 to 30 parts by mass, more preferably 0.01 to 10 parts by mass, even more preferably 0.05 to 20 parts by mass, and particularly preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the polymerizable monomer (A) in the dental curable composition. When the content of the polymerization accelerator is 0.001 part by mass or more, the polymerization proceeds sufficiently and the desired curability is obtained. On the other hand, when the content of the polymerization accelerator is 30 parts by mass or less, sufficient curability is obtained.

[0140] <Fluoride ion releasing substances> The dental hardenable composition of the present invention may further contain a fluoride ion-releasing substance. By containing the fluoride ion-releasing substance, a dental hardenable composition capable of imparting acid resistance to tooth structure can be obtained. Examples of the fluoride ion releasing substance include metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, ytterbium fluoride, etc. The above fluoride ion releasing substances may be used alone or in combination of two or more.

[0141] The dental hardenable composition of the present invention may contain known additives within limits that do not impair the properties of the composition. Examples of the additives include polymerization inhibitors, antioxidants, pigments, dyes, ultraviolet absorbers, solvents such as organic solvents, and thickeners. The additives may be used alone or in combination of two or more kinds. In one embodiment, the content of a solvent (e.g., water, organic solvent) in the dental hardenable composition is preferably less than 1 mass %, more preferably less than 0.1 mass %, and even more preferably less than 0.01 mass %, based on the total mass of the dental hardenable composition. In another embodiment, the dental curable composition is preferably substantially free of water from the viewpoint of achieving the effects of the present invention. The dental curable composition being substantially free of water means that the water content is preferably 1% by mass or less, more preferably 0.1% by mass or less, and even more preferably 0.01% by mass or less, relative to the total amount of the dental curable composition, and may be 0% by mass.

[0142] Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, dibutylhydroquinone, dibutylhydroquinone monomethyl ether, t-butylcatechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, and 3,5-di-t-butyl-4-hydroxytoluene. The content of the polymerization inhibitor is preferably 0.001 to 1.0 mass % relative to 100 mass % of the total amount of monomers in the dental curable composition.

[0143] Furthermore, the dental hardenable composition of the present invention is suitably used as a dental composite resin or a dental cement in the field of dentistry.

[0144] The present invention includes embodiments in which 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. EXAMPLES

[0145] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. Test methods, materials, etc. used in the examples are summarized below.

[0146] <Test Method> (Measurement of the average particle size of inorganic aggregate filler) The inorganic aggregated fillers obtained in each of the following production examples were measured for their volumetric average particle diameter using water as a dispersion medium and a laser diffraction particle size distribution analyzer (product name "SALD-2300", manufactured by Shimadzu Corporation).

[0147] (Evaluation of the shape of inorganic aggregate fillers (secondary particles) and primary particles) The shapes of the inorganic agglomerated fillers and the primary particles constituting the fillers obtained in each of the following production examples were determined by observation under a microscope. The microscope used was a scanning electron microscope (product name "SU3900", manufactured by Hitachi High-Technologies Corporation).

[0148] (Measurement of Microcompressive Hardness of Inorganic Agglomerated Fillers) The inorganic aggregate fillers obtained in the following respective manufacturing examples were subjected to measurement of microcompression hardness in accordance with JIS R 1639-5:2007 using a microcompression tester (product name "MCT-510") manufactured by Shimadzu Corporation. Specifically, the measurements are as follows. A particle mass of size equivalent to d50 of the inorganic agglomerated filler obtained in each of the manufacturing examples below was pressed under the conditions of load: 5 mN, speed: 0.05 mN / sec, and flat indenter: Φ20 μm, and the crushing strength Cs (MPa) of a single granule was calculated from the breaking test force P (N) and particle diameter d (mm). The formula is Cs=2.48P / πd 2 The crushing strength Cs (MPa) of a single granule is the microcompression hardness. Five tests were performed for each inorganic aggregate filler, and the average value was used as the result. Further, only for X-3 in Table 1 below, the measurement conditions were changed to load: 50 mN, speed: 0.5 mN / sec, and flat indenter: Φ20 μm in order to shorten the experimental operation time. The measurement results after changing the conditions can be compared with the conditions before the change, and the change in conditions does not change the measurement results.

[0149] (Measurement of bending strength of cured product) After vacuum degassing, the dental curable composition obtained in each Example and Comparative Example was filled into a stainless steel mold (dimensions 2 mm x 2 mm x 25 mm), pressed against the top and bottom with slide glass, and cured by irradiating light to both sides of the slide glass for 10 seconds at each point, 5 points on each side, to obtain a test piece of the cured product. For each Example and Comparative Example, 5 cured products were prepared, and the cured products were removed from the mold and stored in distilled water at 37 ° C. for 24 hours. For each test piece, the bending strength was measured by a three-point bending test using a precision universal testing machine (manufactured by Shimadzu Corporation, product name "Autograph AG-I 100kN") in accordance with JIS T 6514: 2015 and ISO 4049: 2019 under conditions of a support distance of 20 mm and a crosshead speed of 1 mm / min. The average value (n = 5) of the measured values ​​of each test piece was calculated and used as the bending strength. The bending strength is preferably 140 MPa or more, more preferably 145 MPa or more, and even more preferably 150 MPa or more. There is no particular upper limit to the bending strength, and it may be, for example, 200 MPa or more.

[0150] (Evaluation of abrasiveness of cured product) The dental curable compositions obtained in each of the Examples and Comparative Examples were filled into a polytetrafluoroethylene mold (inner diameter 10 mm × thickness 2.0 mm) and irradiated with light for 10 seconds using a dental polymerization LED light irradiator (product name "PenCure 2000", manufactured by Morita Co., Ltd.). The cured product was removed from the mold, and the clean, smooth upper surface was polished with #600 abrasive paper under dry conditions. Furthermore, using a dental laboratory engine (product name "Volvere i7", manufactured by NSK Ltd.), the specimen was polished for 5 seconds at a rotation speed of approximately 10,000 rpm using a dental rubber abrasive (product name "Compomaster", manufactured by Matsukaze Corporation) under moist conditions to create a polished surface. The gloss of the polished surface was then measured using a gloss meter (product name "VG8000", measurement angle: 60°, manufactured by Nippon Denshoku Industries Co., Ltd.) to determine the ratio (glossiness) to the mirror being 100%, and this was used as an index of the polishability of the cured product. The gloss level is preferably 50% or more, more preferably 55% or more, even more preferably 60% or more, and most preferably 65% ​​or more.

[0151] (Evaluation of operability) For the dental curable compositions obtained in each of the Examples and Comparative Examples, the following operations were carried out based on the following criteria to evaluate operability from the viewpoint of ease of filling operation. A certain amount (about 50 mg) of the dental hardenable composition was spread on a mixing paper using a dental excavator (manufactured by Feed Co., Ltd.) After that, the paste was pressed and spread on the mixing paper several times with the same tool. Those that were not sticky or dry and were easy to fill were rated "○", and among these, those that were particularly excellent in terms of filling operability were rated "◎". On the other hand, those that were sticky or dry and difficult to fill were rated as "X." Each rating was given if four or more of the five preparations met the criteria.

[0152] (Measurement of specific surface area) The specific surface area was measured by the BET multipoint method. The specific surface area was measured by the gas adsorption method using a gas adsorption tester (product name "BELSORP-miniII") and the attached pretreatment device (product name "BELPREP-vacII") (manufactured by Microtrack-Bell Corporation). Approximately 200 mg of the powder to be measured was placed in a measurement sample tube, and vacuum dried for 3 hours while heating to 90°C using a pretreatment device. After that, nitrogen gas molecules with a known adsorption area were adsorbed onto the powder surface using a gas adsorption tester, and the specific surface area of ​​the sample was measured from the amount of adsorption. In addition, the measurement results were analyzed by the BET multipoint method using five points on the adsorption side isotherm where the ratio (P / P0) of the adsorption equilibrium pressure P (kPa) to the saturated vapor pressure P0 (kPa) was in the range of 0.05 to 0.3.

[0153] <Material> (Polymerizable monomer (A)) D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethyleneoxy groups added: 2.6) UDMA: 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate POBMA: m-phenoxybenzyl methacrylate (Kyoeisha Chemical Co., Ltd.)

[0154] (Polymerization initiator (B)) BPO: Benzoyl peroxide CQ: dl-camphorquinone TMDPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide

[0155] (Polymerization accelerator) PDE: Ethyl 4-(N,N-dimethylamino)benzoate

[0156] (Polymerization inhibitor) BHT: 3,5-di-t-butyl-4-hydroxytoluene

[0157] (UV absorber) TN326: "Tinuvin 326" (BASF Japan Ltd.)

[0158] (Inorganic aggregate filler (C)) As the inorganic aggregate filler (C), the one obtained in the following Production Example was used.

[0159] [Filler Production Example 1] Production of inorganic agglomerated filler (C-1) Commercially available barium glass (product name "GM27884 NanoFine180", average particle size: 180 nm, manufactured by Schott) was sieved with a #150 (mesh size: 108 μm) sieve, and then sieved more finely with a #255 (mesh size: 57 μm) sieve to remove coarse particles and impurities. After that, glass powder was added to water to a concentration of 20% to prepare a slurry, and while stirring with a mechanical stirrer, ultrasonic waves were irradiated for about 1 to 3 hours to disperse the aggregated particles. Furthermore, a slurry in which even finer particles were dispersed was produced using an ultra-high pressure wet type atomizer (product name "Nanovata (registered trademark) L-AS", manufactured by Yoshida Kikai Kogyo Co., Ltd.). Next, a solution prepared by stirring 11 parts by mass of 3-methacryloyloxypropyltrimethoxysilane (KBM-503), 50 parts by mass of distilled water, and 0.1 parts by mass of acetic acid in a round-bottom flask for 1 hour, with the barium glass contained in the obtained slurry being taken as 100 parts by mass, was added to the slurry and stirred for 1 hour. After the 3-methacryloyloxypropyltrimethoxysilane was sufficiently reacted with the surface of the filler by the stirring, the mixture was spray-dried and granulated using a spray dryer (manufactured by Nippon Buchi Co., Ltd.) The spray drying was performed under the conditions of a drying temperature of 170° C. and a flow rate of 5 g / min. The obtained filler was transferred to a heat-resistant ceramic dish and fired at 700° C. for 2 hours using an electric furnace (manufactured by Yamato Scientific Co., Ltd.). The filler obtained after firing was added to 2-propanol at an arbitrary concentration to prepare a slurry. The slurry was stirred for 1 hour. 3-Methacryloyloxypropyltrimethoxysilane, 2-propanol, and acetic acid were mixed in a round-bottom flask in a ratio of 11 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, 50 parts by mass of 2-propanol, and 0.1 parts by mass of acetic acid per 100 parts by mass of filler in the slurry. The mixture was stirred for 1 hour in a round-bottom flask, and the resulting solution was added to the slurry and stirred at room temperature for an additional 1 hour. After 2-propanol was distilled off under reduced pressure, the residue was vacuum dried at 40° C. for 16 hours and then heated at 90° C. for 3 hours to obtain a surface-treated inorganic aggregate filler (C-1).

[0160] [Filler Production Example 2] Production of inorganic agglomerated filler (C-2) Inorganic agglomerated filler (C-2) was produced in the same manner as inorganic agglomerated filler (C-1), except that commercially available barium glass (product name "GM27884 NanoFine180") was changed to barium glass (product name "GM27884 UF0.4", average particle size: 400 nm, manufactured by Schott Corporation).

[0161] [Filler Production Example 3] Production of inorganic agglomerated filler (C-3) Inorganic agglomerated filler (C-3) was produced in the same manner as inorganic agglomerated filler (C-1), except that 11 parts by mass of 3-methacryloyloxypropyltrimethoxysilane was changed to 22 parts by mass of 3-methacryloyloxypropyltrimethoxysilane.

[0162] [Filler Production Example 4] Production of inorganic agglomerated filler (C-4) Inorganic agglomerated filler (C-4) was produced in the same manner as inorganic agglomerated filler (C-1), except that the firing at 700°C for 2 hours was changed to firing at 700°C for 4 hours.

[0163] (Non-agglomerated filler (D)) As the non-agglomerated filler (D), the one obtained in the following Production Example was used. [Filler Production Example 5] Production of non-agglomerated filler (D-1) 100 parts by mass of commercially available barium glass (product name "GM27884 NanoFine180", average particle size: 180 nm, manufactured by Schott Co.), 7 parts by mass of 3-methacryloyloxypropyltrimethoxysilane, and 173 parts by mass of toluene were placed in a three-neck flask and stirred at room temperature for 2 hours. After the toluene was distilled off under reduced pressure, the mixture was vacuum dried at 40°C for 16 hours and further heated at 90°C for 3 hours to obtain an inorganic filler provided with a surface treatment layer. The obtained inorganic filler (non-agglomerated filler (D-1)) had an average particle size of 0.2 μm and a specific surface area of ​​35 m 2 / g.

[0164] [Filler Production Example 6] Production of non-agglomerated filler (D-2) 100 parts by mass of roughly spherical ultrafine silica particles (product name "Aerosil (registered trademark) 130", manufactured by Nippon Aerosil Co., Ltd.) having an average particle diameter of 20 nm were surface-treated with 40 parts by mass of 3-methacryloyloxypropyltrimethoxysilane to obtain a non-aggregated filler (D-2).

[0165] (Inorganic agglomerated fillers other than inorganic agglomerated filler (C)) As inorganic agglomerated fillers other than the inorganic agglomerated filler (C), those obtained in the following Production Examples were used.

[0166] [Filler Production Example 7] Production of inorganic agglomerated filler (X-1) Inorganic agglomerated filler (X-1) was produced in the same manner as inorganic agglomerated filler (C-1), except that commercially available barium glass (product name "GM27884 NanoFine180") was changed to barium glass (product name "GM27884 UF0.7", average particle size: 700 nm, manufactured by Schott Corporation).

[0167] [Filler Production Example 8] Production of inorganic agglomerated filler (X-2) Inorganic agglomerated filler (X-2) was produced in the same manner as inorganic agglomerated filler (C-1), except that commercially available barium glass (product name "GM27884 NanoFine180") was changed to non-agglomerated filler (D-2).

[0168] [Filler Production Example 9] Production of inorganic agglomerated filler (X-3) Inorganic agglomerated filler (X-3) was produced in the same manner as inorganic agglomerated filler (C-1), except that the firing temperature was changed from 700°C to 900°C.

[0169] [Filler Production Example 10] Production of inorganic agglomerated filler (X-4) Inorganic agglomerated filler (X-4) was produced in the same manner as inorganic agglomerated filler (C-1), except that 11 parts by mass of 3-methacryloyloxypropyltrimethoxysilane was replaced with 11 parts by mass of polyvinyl alcohol (product name "PVA-117", manufactured by Kuraray Co., Ltd.).

[0170] [Filler Production Example 11] Production of inorganic agglomerated filler (X-5) The cluster particle filler was produced by the sol-gel method described in WO01 / 030304. Specifically, the procedure is as follows. A 5.0 kg portion of silica nanosized sol (Nalco 1042 sol) was weighed out and the pH of the sol was adjusted to 2.5 using dilute nitric acid. The pH adjusted sol was slowly added to 2.95 kg of zirconium acetate and stirred for 1 hour. The mixture was spray-dried and granulated using a spray dryer (manufactured by Nippon Buchi Co., Ltd.). The spray drying was carried out under conditions of a drying temperature of 170°C and a flow rate of 5 g / min. The obtained filler was fired at 550°C for 4 hours. The fired filler was then pulverized in a ball mill for 160 hours to produce an inorganic agglomerated filler (X-5).

[0171] Table 1 shows the production conditions and physical properties of the fillers obtained in each production example.

[0172] [Table 1]

[0173] [Production Example 1 of Polymerizable Monomer-Containing Composition] Production of Polymerizable Monomer-Containing Composition (M-1) A polymerizable monomer-containing composition (M-1) was prepared by dissolving 0.5 parts by mass of BPO as a chemical polymerization initiator, 0.4 parts by mass of CQ as a photopolymerization initiator, 0.5 parts by mass of TMDPO, 0.4 parts by mass of PDE as a polymerization accelerator, 0.01 parts by mass of BHT as a polymerization inhibitor, and 0.5 parts by mass of TN326 as an ultraviolet absorber in 20 parts by mass of D-2.6E, 50 parts by mass of UDMA, and 30 parts by mass of POBMA.

[0174] [Examples 1 to 5 and Comparative Examples 1 to 5] The polymerizable monomer-containing composition (M-1) obtained in the above-mentioned manufacturing example, the inorganic agglomerated fillers (C-1) to (C-4), the inorganic agglomerated fillers (X-1) to (X-5) other than the inorganic agglomerated filler (C), and the non-agglomerated fillers (D-1) to (D-2) were kneaded in the composition ratios shown in Table 2 below to make a homogenous mixture, which was then vacuum-defoamed to prepare paste-like dental curable compositions of Examples 1 to 5 and Comparative Examples 1 to 5. The properties of the dental hardenable compositions thus prepared were evaluated by the methods described above, and the results are shown in Table 2 below.

[0175] [Table 2]

[0176] From the above results, it was confirmed that the dental hardenable composition of the present invention has good paste properties when used, is excellent in operability, and has excellent mechanical strength and polishability of the hardened product.

[0177] In Comparative Example 1, the average particle size of the primary particles constituting the inorganic aggregate filler was too large, and the polishing properties were poor. In Comparative Example 2, the primary particles constituting the inorganic aggregated filler were spherical in shape, the microcompression hardness was out of range, and the mechanical strength of the cured product was insufficient. In Comparative Example 3, the microcompression hardness was outside the range, the paste properties were poor, and the polishing properties of the cured product were poor. In Comparative Example 4, the average particle size of the primary particles constituting the inorganic agglomerated filler was too large, the microcompression hardness was outside the range, the paste properties were poor, the abrasiveness of the cured product was poor, and the mechanical strength of the cured product was also insufficient. In Comparative Example 5, the primary particles constituting the inorganic aggregated filler were spherical in shape, the microcompression hardness was out of range, and the mechanical strength of the cured product was insufficient. [Industrial Applicability]

[0178] The dental curable composition of the present invention is suitably used as a dental composite resin or a dental cement in the field of dentistry. [Explanation of symbols]

[0179] 1. Inorganic particles to be measured 2 Indenter 3 Test force 4. Compression Displacement

Claims

1. A dental curable composition comprising a polymerizable monomer (A), a polymerization initiator (B), and an inorganic aggregated filler (C), wherein the inorganic aggregated filler (C) satisfies the following (c1), (c2), and (c3): (c1) The shape of the primary particles constituting the inorganic aggregated filler is amorphous (excluding spherical); (c2) The average particle diameter of the primary particles constituting the inorganic aggregated filler is 650 nm or less; (c3) The micro-compressive hardness of the inorganic aggregated filler is 10 to 300 MPa; and simultaneously satisfies the above conditions.

2. The dental curable composition according to claim 1, wherein the shape of the inorganic aggregated filler (C) is spherical.

3. The dental curable composition according to claim 1 or 2, wherein the content of the inorganic aggregated filler (C) is 5 to 50% by mass.

4. The specific surface area of the inorganic aggregate filler (C) is 80 m 2 / g or less. The dental curable composition according to claim 1 or 2.

5. The dental curable composition according to claim 1 or 2, further comprising a non-aggregated filler (D) having an average particle diameter of the primary particles of 500 nm or less.

6. The dental curable composition according to claim 5, wherein the content of the non-aggregated filler (D) is 5 to 45% by mass.

7. The following (c1), (c2), and (c3): (c1) The shape of the primary particles constituting the inorganic aggregated filler is amorphous (excluding spherical); (c2) The average particle diameter of the primary particles constituting the inorganic aggregated filler is 650 nm or less; (c3) The micro-compressive hardness of the inorganic aggregated filler is 10 to 300 MPa. and simultaneously satisfies the above conditions. A dental inorganic aggregated filler (C).

8. A method for producing an inorganic aggregated filler, comprising a mixing step of mixing a dispersion liquid obtained by dispersing inorganic particles having an average particle diameter of 650 nm or less of primary particles in a solvent with a binder containing at least one metal oxide selected from the group consisting of silicon, barium, aluminum, or transition metal elements of Groups 3 to 11 to obtain a mixed liquid, a drying step of drying the mixed liquid to obtain a dried body, and a firing step of firing the dried body.

9. The method for producing an inorganic aggregated filler according to claim 8, wherein in the mixing step, the addition amount of the binder with respect to 100 parts by mass of the inorganic particles is 1 to 35 parts by mass.

10. The method for producing an inorganic aggregated filler according to claim 8 or 9, wherein the binder is a silane coupling agent represented by the following general formula (1) R 1 n SiY 4-n (1) (In the formula, R 1 is a substituted or unsubstituted hydrocarbon group having 1 to 25 carbon atoms, Y represents an alkoxy group having 1 to 4 carbon atoms, an acyloxy group having 1 to 5 carbon atoms, a hydroxy group, a halogen atom or a hydrogen atom, n is an integer of 0 to 3, provided that when there are a plurality of R 1 and Y, they may be the same or different from each other.) The method for producing an inorganic aggregated filler according to claim 8 or 9, wherein the binder is a silane coupling agent represented by the following general formula (1)

11. The method for producing an inorganic aggregated filler according to claim 8 or 9, wherein the drying step is spray drying.

12. The method for producing an inorganic aggregated filler according to claim 8 or 9, wherein in the firing step, the firing temperature is 30 to 80% of the melting temperature of the primary particles or the melting point temperature of the main component forming the primary particles.

13. The method for producing an inorganic aggregated filler according to claim 8 or 9, wherein in the firing step, the firing temperature is 600 to 800°C.

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