Dental curable composition

Abstract

To provide a dental curable composition that ensures superior mechanical strength of a cured product during chemical hardening, while exhibiting superior durability of adhesion to enamel.SOLUTION: A dental curable composition includes a polymerizable monomer (a) with an acidic group, a peroxide (b), and a polymerization accelerator (c). The polymerization accelerator (c) includes a copper compound (c-1) and a bromide salt (c-2) (excluding copper bromide). A copper atomic concentration is 0.2 μg / g or more as determined by ICP mass spectrometry (ICP-MS), and a bromine atomic concentration is 20 μg / g or more as determined by combustion ion chromatography (CIC).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a dental hardenable composition comprising a polymerizable monomer having an acidic group, a peroxide, and a polymerization accelerator, and more particularly to a dental hardenable composition which provides a hardened product having excellent mechanical strength upon chemical hardening and excellent adhesion durability to enamel. [Background technology]

[0002] For dental hardenable compositions used as dental cements, dental adhesives, composite resins, self-adhesive composite resins, sealants, dental self-polymerizing resins, etc., hardenable compositions containing a polymerizable monomer and a radical polymerization initiator are widely used.

[0003] Radical polymerization initiators are broadly classified into photopolymerization initiators and chemical polymerization initiators, and in recent years, dual cure products that contain both have been widely used in clinical practice. Among radical polymerization initiators, chemical polymerization initiators are generally a combination of an oxidizing agent and a reducing agent. By mixing these, a so-called redox reaction occurs to generate radicals, which then initiates a polymerization reaction and progresses curing. A dental composition containing a redox polymerization initiator is usually stored divided into a composition containing an oxidizing agent and a composition containing a reducing agent, and the two compositions are mixed together immediately before use.

[0004] When dental curable compositions are used for applications requiring adhesion to an adherend, such as dental cements, dental adhesives, self-adhesive composite resins, and sealants, compositions containing an acidic component are generally used. In recent years, radical polymerization initiators containing metal salts have been proposed as redox-based polymerization initiators for use in such compositions containing an acidic component (e.g., Patent Documents 1 and 2).

[0005] Patent Document 1 proposes a redox-based polymerization initiator containing a barbituric acid derivative and / or malonylsulfamide, a metal salt compound, and a halide, which achieves storage stability and a sufficiently short curing time.

[0006] Furthermore, Patent Document 2 discloses a redox polymerization initiator containing a benzotriazole compound and / or a benzimidazole compound, an α-diketone compound, an aromatic sulfinate, and a copper compound. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Special Publication No. 2013-538837 [Patent Document 2] International Publication No. 2012 / 086189 Summary of the Invention [Problem to be solved by the invention]

[0008] However, according to the present inventors' investigations, although the dental curable compositions described in Patent Documents 1 and 2 have excellent mechanical strength, there is room for further improvement in terms of adhesion durability to enamel.

[0009] Therefore, an object of the present invention is to provide a dental hardenable composition which has excellent mechanical strength of the cured product when chemically cured and has excellent adhesion durability to enamel. [Means for solving the problem]

[0010] The present inventors have continued their intensive research to solve the above problems, and as a result, have found that a dental hardenable composition containing a polymerizable monomer having an acidic group, a polymerization initiator, and a polymerization accelerator (c), the polymerization accelerator (c) containing a copper compound (c-1) and a bromide salt (c-2) (excluding copper bromide), a copper atom concentration determined by inductively coupled plasma mass spectrometry (ICP-MS) (hereinafter sometimes abbreviated as "ICP-MS") within a specific range, and a bromine atom concentration determined by combustion ion chromatography (CIC) measurement method (hereinafter sometimes abbreviated as "CIC measurement method") within a specific range, has excellent mechanical strength of the hardened product when chemically hardened, and excellent adhesion durability to enamel. Based on these findings, the present inventors have further studied and completed the present invention.

[0011] That is, the present invention includes the following inventions. [1] A polymerizable monomer (a) having an acidic group, a peroxide (b), and a polymerization accelerator (c), The polymerization accelerator (c) contains a copper compound (c-1) and a bromide salt (c-2) (excluding copper bromide), The atomic copper concentration as determined by inductively coupled plasma mass spectrometry (ICP-MS) is 0.2 μg / g or more, and A dental hardenable composition having a bromine atom concentration of 20 μg / g or more as determined by combustion ion chromatography (CIC) measurement. [2] The dental hardenable composition according to [1], wherein the polymerization accelerator (c) further contains an aromatic sulfinic acid compound (c-3). [3] The dental hardenable composition according to [1] or [2], wherein the polymerizable monomer (a) having an acidic group includes at least one selected from the group consisting of a polymerizable monomer having a phosphoric acid group, a polymerizable monomer having a carboxylic acid group, and a polymerizable monomer having a sulfonic acid group. [4] The dental curable composition according to any one of [1] to [3], wherein the peroxide (b) contains an organic peroxide (b-1). [5] The dental hardenable composition according to any one of [1] to [4], wherein the polymerization accelerator (c) further contains an amine reducing agent (c-4). [6] The dental hardenable composition according to any one of [1] to [5], wherein the polymerization accelerator (c) further contains a sulfur-containing reducing inorganic compound (c-5). [7] The dental curable composition according to any one of [1] to [6], further comprising a polymerizable monomer having no acidic group. [8] The dental hardenable composition according to any one of [1] to [7], further comprising a filler (d). [9] The dental curable composition according to any one of [1] to [8], further comprising a silane coupling agent (e).

[10] A composition comprising a first agent and a second agent, the first agent contains the polymerizable monomer (a) having an acidic group, the peroxide (b), and the copper compound (c-1), The dental hardenable composition according to any one of [1] to [9], wherein the second agent contains the bromide salt (c-2). Effect of the Invention

[0012] According to the present invention, there is provided a dental hardenable composition which exhibits excellent mechanical strength of the cured product upon chemical hardening and excellent adhesion durability to enamel. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The present invention will be described in detail below. The dental hardenable composition of the present invention comprises a polymerizable monomer (a) having an acidic group, a peroxide (b), and a polymerization accelerator (c), the polymerization accelerator (c) comprising a copper compound (c-1) and a bromide salt (c-2); The atomic copper concentration as determined by inductively coupled plasma mass spectrometry (ICP-MS) is 0.2 μg / g or more, and The bromine atom concentration determined by combustion ion chromatography (CIC) is 20μg / g or more. This provides a dental hardenable composition that exhibits excellent mechanical strength of the cured product upon chemical hardening and excellent adhesion durability to enamel.

[0014] The reason why the configuration of the present invention provides the above-mentioned excellent effects is not entirely clear, but is presumed to be as follows. First, the copper compound (c-1) and the bromide salt (c-2) undergo coordination substitution in the reaction system, which further improves the catalytic activity of the copper compound. More specifically, bromide ions are generated from the bromide salt (c-2), and the bromide ions are coordinated as ligands to the copper atoms contained in the copper compound (c-1). It is presumed that the reactivity of the copper atoms coordinated with the bromide ions is improved by the electron attraction of the bromide ions. This improved reactivity facilitates the interaction between the copper compound having the copper atoms coordinated and substituted with the bromide ions and the polymerization initiator, peroxide (b). This allows the chemical polymerization to proceed more efficiently, improving the mechanical strength of the cured product obtained by chemical curing. On the other hand, this selective reactivity improvement effect obtained by copper compounds having copper atoms in a coordinated substitution state with bromide ions is not seen in halide ions other than bromide ions, and almost no interaction with peroxide (b) is obtained. In addition, the adhesion durability to enamel is estimated as follows. The dental hardenable composition has excellent adhesion to enamel due to the polymerizable monomer (a) having an acidic group, and furthermore, the peroxide (b) and polymerization accelerator (c) contained in the dental hardenable composition are consumed more efficiently in the polymerization reaction, and the polymerization reaction also proceeds sufficiently at the interface between the hardened product of the dental hardenable composition and the tooth structure, resulting in less brittle hardened product at the interface. As a result, the occurrence of a difference in hardness between the enamel and the hardened product is suppressed, and these components of the dental hardenable composition act together, which is considered to result in a product with excellent adhesion durability to enamel.

[0015] [Polymerizable monomer (a) having an acidic group] The dental curable composition of the present invention contains a polymerizable monomer (a) having an acidic group. Examples of the polymerizable monomer (a) having an acidic group 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 sulfonic acid group, or a carboxylic acid group, and having at least one polymerizable group such as an acryloyl group, a methacryloyl group, a vinyl group, or a styrene group. The polymerizable monomer (a) having an acidic group has affinity with the adherend (such as an abutment tooth), has a demineralizing effect on the tooth substance, and is excellent in adhesiveness to the tooth substance. Specific examples of the polymerizable monomer (a) having an acidic group are described below. In the following, the term (meth)acrylic is a general term for methacrylic and acrylic.

[0016] 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, and 7-(meth)acryloyloxyheptyl dihydrogen phosphate. acrylate, 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, 20-(meth)acryloyloxyoctyl dihydrogen phosphate, Acryloyloxyeicosyl dihydrogen phosphate, bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxyethyl]hydrogen phosphate, Examples of suitable hydrogen phosphate compounds include 2-(meth)acryloyloxyethyl-2-bromoethyl hydrogen phosphate, bis[2-(meth)acryloyloxydecyl]hydrogen phosphate, 1,3-di(meth)acryloyloxypropyl dihydrogen phosphate, 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-2-bromoethyl hydrogen phosphate, bis[2-(meth)acryloyloxy-(1-hydroxymethyl)ethyl]hydrogen phosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0017] Examples of the polymerizable monomer having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl]pyrophosphate, bis[4-(meth)acryloyloxybutyl]pyrophosphate, bis[6-(meth)acryloyloxyhexyl]pyrophosphate, bis[8-(meth)acryloyloxyoctyl]pyrophosphate, bis[10-(meth)acryloyloxydecyl]pyrophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0018] Examples of the polymerizable monomer having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate, and the like. Examples of suitable alkyl acrylates include acryloyloxyethyl acrylate, 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)acryloyloxyeicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0019] 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 phosphonoacetate, 10-(meth)acryloyloxydecyl phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0020] Examples of the polymerizable monomer having a sulfonic acid group include 2-(meth)acrylamide-2-methylpropanesulfonic acid, styrenesulfonic acid, and 2-sulfoethyl(meth)acrylate.

[0021] Examples of the polymerizable monomer having a carboxylic acid group include a polymerizable monomer having one carboxyl group in the molecule and a polymerizable monomer having a plurality of carboxyl groups in the molecule.

[0022] Examples of polymerizable monomers having one carboxyl group in the molecule include (meth)acrylic acid, N-(meth)acryloylglycine, N-(meth)acryloylaspartic acid, O-(meth)acryloyltyrosine, N-(meth)acryloyltyrosine, N-(meth)acryloylphenylalanine, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-o-aminobenzoic acid, p-vinylbenzoic acid, 2-(meth)acryloyloxy Examples of the acid halides include benzoic acid, 3-(meth)acryloyloxybenzoic acid, 4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, N-(meth)acryloyl-4-aminosalicylic acid, 2-(meth)acryloyloxyethyl hydrogen succinate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen maleate, and acid halides thereof.

[0023] Examples of polymerizable monomers having multiple carboxyl groups 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 ...4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 4-(meth)acrylo Examples of the acid anhydride include acryloyloxyethyl trimellitate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxybutyl trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, and acid anhydrides or acid halides thereof.

[0024] The above-mentioned polymerizable monomer (a) having an acidic group may be used alone or in combination of two or more. Among these polymerizable monomers having an acidic group, in terms of excellent adhesion to tooth structure (particularly initial adhesion to enamel and adhesion durability), one or more selected from the group consisting of polymerizable monomers having a phosphoric acid group, polymerizable monomers having a carboxylic acid group, and polymerizable monomers having a sulfonic acid group are preferred, and one or more selected from the group consisting of polymerizable monomers having a phosphoric acid group with two or more hydroxyl groups bonded to a phosphorus atom, polymerizable monomers having multiple carboxyl groups in the molecule, and polymerizable monomers having a sulfonic acid group are more preferred, and 10-(meth)arylamine is more preferred. More preferred is one or more selected from the group consisting of acryloyloxydecyl dihydrogen phosphate, 1,3-di(meth)acryloyloxypropyl dihydrogen phosphate, 2-(meth)acryloyloxyethyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 2-(meth)acrylamido-2-methylpropanesulfonic acid, and 11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid.

[0025] The content of the polymerizable monomer (a) having an acidic group is preferably 1 to 50 parts by mass, more preferably 2 to 30 parts by mass, and even more preferably 5 to 20 parts by mass, in 100 parts by mass of the total amount of the polymerizable monomer components in the dental curable composition of the present invention. When the content of the polymerizable monomer (a) having an acidic group is 1 part by mass or more, it is easy to obtain high adhesion to teeth and various dental adherends. In addition, when the content of the polymerizable monomer (a) having an acidic group is 50 parts by mass or less, it is easy to maintain a balance between the polymerizability and the adhesiveness. In this specification, the "total amount of polymerizable monomer components" means the total amount of the polymerizable monomer (a) having an acidic group and the polymerizable monomer not having an acidic group.

[0026] The dental hardenable composition of the present invention may further contain a polymerizable monomer that does not have an acidic group. In the present invention, the polymerizable monomer having no acidic group is a polymerizable monomer having no acidic group and being polymerized by a radical polymerization reaction proceeding in the presence of a polymerization initiator system. The polymerizable monomer having no acidic group in the present invention may be used alone or in combination of two or more. Suitable examples of the polymerizable monomer having no acidic group include the following water-soluble polymerizable monomers and hydrophobic polymerizable monomers.

[0027] The water-soluble polymerizable monomer means a polymerizable monomer having a solubility in water of 10% by mass or more at 25° C. A monomer having a solubility of 30% by mass or more is preferable, and a monomer that can be dissolved in water at any ratio at 25° C. is more preferable. The water-soluble polymerizable monomer promotes the penetration of the components of the dental hardenable composition into the tooth structure, and also penetrates into the tooth structure itself to adhere to the organic components (collagen) in the tooth structure.

[0028] Examples of the water-soluble polymerizable monomer include monofunctional (meth)acrylic acid ester polymerizable monomers such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate (hereinafter sometimes abbreviated as "HEMA"), 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,3-dihydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and 2-((meth)acryloyloxy)ethyl trimethylammonium chloride; and bifunctional (meth)acrylic acid ester polymerizable monomers such as polyethylene glycol di(meth)acrylate (average number of moles of oxyethylene groups added: 9 or more), with 2-hydroxyethyl (meth)acrylate being preferred. In this specification, "(meth)acrylic" means acrylic and methacrylic, and the same applies to expressions such as "(meth)acryloyl" and "(meth)acrylate".

[0029] The hydrophobic polymerizable monomer means a polymerizable monomer having a solubility in water at 25°C of less than 10% by mass. Examples of the hydrophobic polymerizable monomer include monofunctional and bifunctional polymerizable monomers of aromatic compounds, monofunctional and bifunctional polymerizable monomers of aliphatic compounds, trifunctional or higher functional polymerizable monomers, etc. The hydrophobic polymerizable monomer improves the mechanical strength of the cured product of the dental curable composition, the handleability of the dental curable composition, etc.

[0030] Examples of aromatic compound-based monofunctional polymerizable monomers include benzyl (meth)acrylate, p-cumyl-phenoxyethylene glycol (meth)acrylate, 2-phenoxybenzyl (meth)acrylate, etc. Among these, benzyl methacrylate and p-cumyl-phenoxyethylene glycol methacrylate are preferred.

[0031] Examples of the aromatic compound-based bifunctional polymerizable monomer include aromatic di(meth)acrylates. Specific examples of aromatic bifunctional polymerizable monomers include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(3-acryloyloxy-2-hydroxypropoxy)phenyl]propane, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (hereinafter sometimes abbreviated as "Bis-GMA"), 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)acryloyloxytetra ... p) acryloyloxypentaethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, 1,4-bis(2-(meth)acryloyloxyethyl)pyromellitate, and the like. Among these, 2,2-bis[4-(3-methacryloyloxy-2-hydroxypropoxy)phenyl]propane and 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles added of ethoxy groups: 2.6) (hereinafter sometimes abbreviated as "D-2.6E") are preferred.

[0032] Examples of the aliphatic compound-based monofunctional polymerizable monomer include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobornyl (meth)acrylate, stearyl (meth)acrylate, dicyclopentanyl (meth)acrylate, butoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, etc. Among these, isobornyl methacrylate is preferred.

[0033] Examples of the aliphatic compound-based bifunctional polymerizable monomer include erythritol di(meth)acrylate, sorbitol di(meth)acrylate, mannitol di(meth)acrylate, pentaerythritol di(meth)acrylate, dipentaerythritol di(meth)acrylate, glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol diacrylate, triethylene glycol dimethacrylate (hereinafter sometimes abbreviated as "TEGDMA"), propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, and the like. Examples of the polymerizable monomer include bifunctional (meth)acrylic acid ester polymerizable monomers such as acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate, and 1,2-bis(3-methacryloyloxy-2-hydroxypropyloxy)ethane; and (meth)acrylamide polymerizable monomers such as N-methacryloyloxyethylacrylamide, N-methacryloyloxypropylacrylamide, N-methacryloyloxybutylacrylamide, N-(1-ethyl-(2-methacryloyloxy)ethyl)acrylamide, and N-(2-(2-methacryloyloxyethoxy)ethyl)acrylamide. Among these, glycerol dimethacrylate, triethylene glycol di(meth)acrylate, neopentyl glycol dimethacrylate, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate, and 1,2-bis(3-methacryloyloxy-2-hydroxypropyloxy)ethane are preferred.

[0034] 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 tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate, 1,7-diacryloyloxy-2,2,6,6-tetraacryloyloxymethyl-4-oxaheptane, and the like.

[0035] Among the polymerizable monomers not having an acidic group, HEMA, Bis-GMA, D-2.6E and TEGDMA are more preferred from the viewpoints of the adhesive strength and polymerization curability of the dental hardenable composition of the present invention.

[0036] The above-mentioned polymerizable monomers not having an acidic group (water-soluble polymerizable monomers and hydrophobic polymerizable monomers) may each be contained alone or in combination of two or more kinds. The content of the polymerizable monomer not containing an acidic group is not particularly limited as long as the effects of the present invention are achieved. However, in terms of the high permeability of the composition into tooth structure and excellent adhesion, and the cured product having sufficient mechanical strength, the content is preferably in the range of 50 to 99 parts by mass, more preferably in the range of 60 to 98 parts by mass, and even more preferably in the range of 70 to 95 parts by mass, per 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention.

[0037] Next, the polymerization initiator system will be described. The dental hardenable composition of the present invention contains a peroxide (b) and a polymerization accelerator (c) as a polymerization initiator system, and the polymerization accelerator (c) contains a copper compound (c-1) and a bromide salt (c-2). That is, the dental hardenable composition of the present invention contains a peroxide (b), a copper compound (c-1), and a bromide salt (c-2).

[0038] [Peroxide (b)] The peroxide (b) of the present invention includes organic peroxide (b-1) and inorganic peroxide (b-2). These are not particularly limited and known chemical polymerization initiators can be used. The organic peroxide (b-1) and inorganic peroxide (b-2) may be used alone or in combination of two or more. As described above, since the peroxide (b) interacts with a copper compound having a copper atom in a state of being coordinated and substituted with a bromide ion, any peroxide having a peroxy group (-OO- group) can be used, and the effects of the present invention can be achieved. As described above, the peroxide (b) interacts with the copper compound having a copper atom in a coordinated substitution state with a bromide ion having improved reactivity, and chemical polymerization proceeds more efficiently, resulting in improved mechanical strength of the resulting cured product. In addition, the peroxide (b) and the bromide salt (c-2) as a polymerization accelerator are consumed more efficiently in the polymerization reaction, and the polymerization reaction proceeds sufficiently at the interface between the hardened product of the dental hardenable composition and the tooth structure, resulting in less brittle hardened product at the interface. As a result, this acts in conjunction with the excellent adhesion to enamel provided by the polymerizable monomer (a) having an acidic group, resulting in excellent adhesion durability to enamel.

[0039] Examples of the organic peroxide (b-1) include diacyl peroxides, peroxy esters, dialkyl peroxides, peroxy ketals, ketone peroxides, and hydroperoxides.

[0040] Specific examples of diacyl peroxides include isobutyryl peroxide, 2,4-dichlorobenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide, octanoyl peroxide, lauroyl peroxide, stearyl peroxide, succinic acid peroxide, m-toluoylbenzoyl peroxide, and benzoyl peroxide.

[0041] Any known peroxyesters can be used without any limitations as long as they have an acyl group on one side of a peroxy group (--OO-- group) and a hydrocarbon group (or a group similar thereto) on the other side. Specific examples include α,α-bis(neodecanoylperoxy)diisopropylbenzene, cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxy neodecanoate, t-hexyl peroxy neodecanoate, t-butyl peroxy neodecanoate, t-hexyl peroxy pivalate, t-butyl peroxy pivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, t- Examples of the peroxyalkylene oxide include butyl peroxyisobutyrate, t-hexyl peroxyisopropyl monocarbonate, t-butyl peroxymaleic acid, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxylaurate, 2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butyl peroxyacetate, t-butyl peroxy-m-toluoyl benzoate, t-butyl peroxybenzoate (hereinafter sometimes abbreviated as "BPB"), and bis(t-butylperoxy)isophthalate. Among these, from the viewpoints of storage stability and reactivity, t-butyl peroxymaleic acid, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxybenzoate, t-butyl peroxyisopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, and t-butyl peroxyacetate are preferred, with t-butyl peroxybenzoate being more preferred.

[0042] Specific examples of dialkyl peroxides include α,α-bis(t-butylperoxy)diisopropylbenzene, dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, t-butylcumyl peroxide, di-t-butyl peroxide, and 2,5-dimethyl-2,5-bis(t-butylperoxy)3-hexyne.

[0043] Specific examples of peroxyketals include 1,1-bis(t-hexylperoxy)3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexanone, 1,1-bis(t-butylperoxy)cyclohexane, 1,1-bis(t-butylperoxy)cyclodecane, 2,2-bis(t-butylperoxy)butane, n-butyl-4,4-bis(t-butylperoxy)valerate, and 2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane.

[0044] Specific examples of ketone peroxides include methyl ethyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, methylacetoacetate peroxide, and acetylacetone peroxide.

[0045] Specific examples of hydroperoxides include cumene hydroperoxide, t-butyl hydroperoxide, t-hexyl hydroperoxide, p-menthane hydroperoxide, diisopropylbenzene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide (hereinafter sometimes abbreviated as "THP").

[0046] The inorganic peroxide (b-2) may include peroxodisulfate and peroxodiphosphate. Among these, peroxodisulfate is preferred from the viewpoint of curability. Specific examples of peroxodisulfate include sodium peroxodisulfate, potassium peroxodisulfate (hereinafter sometimes abbreviated as KPS), aluminum peroxodisulfate, and ammonium peroxodisulfate.

[0047] Among the peroxides (b), hydroperoxides and peroxyesters are particularly preferred. Among the hydroperoxides, t-butyl hydroperoxide, cumene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide are preferably used. Among the peroxyesters, t-butyl peroxybenzoate is preferably used.

[0048] The peroxide (b) may be used alone or in combination of two or more kinds. From the viewpoints of hardening, mechanical strength, and adhesion to tooth structure (particularly adhesion durability to enamel), the content of peroxide (b) is preferably in the range of 0.01 to 10 parts by mass per 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention.

[0049] [Polymerization accelerator (c)] The dental hardenable composition of the present invention contains a copper compound (c-1) as a polymerization accelerator (c). As mentioned above, by including copper compound (c-1), when combined with bromide salt (c-2), the reactivity of copper atom is improved by electron attraction by bromide ion, and the interaction between copper compound having copper atom in a state of coordinate substitution with bromide ion and peroxide (b) which is a polymerization initiator is easily generated. As a result, chemical polymerization proceeds more efficiently, and the mechanical strength of the resulting cured product is improved. In addition, the peroxide (b) and the copper compound (c-1) as a polymerization accelerator are consumed more efficiently in the polymerization reaction, and the polymerization reaction proceeds sufficiently at the interface between the dental hardenable composition hardened product and tooth structure, resulting in less brittle hardened product at the interface. As a result, this acts in conjunction with the excellent adhesion to enamel provided by the polymerizable monomer (a) having an acidic group, resulting in excellent adhesion durability to enamel.

[0050] Examples of the copper compound (c-1) include copper(II) carboxylate, copper(II) β-diketone, copper(II) β-ketoester, copper alkoxide, copper dithiocarbamate, and salts of copper and inorganic acids. Examples of copper(II) carboxylates include copper(II) citrate, copper(II) acetate, copper(II) phthalate, copper(II) tartrate, copper(II) oleate, copper(II) octoate, copper(II) octenoate, copper(II) naphthenate, copper(II) methacrylate, and copper(II) 4-cyclohexylbutyrate. Examples of β-diketone copper(II) include acetylacetonate copper(II), trifluoroacetylacetonate copper(II), hexafluoroacetylacetonate copper(II), 2,2,6,6-tetramethyl-3,5-heptanedionato copper(II), and benzoylacetonate copper(II). Examples of the β-ketoester copper(II) include ethyl acetoacetate copper(II). Examples of copper alkoxides include copper(II) methoxide, copper(II) ethoxide, copper(II) isopropoxide, copper(II) 2-(2-butoxyethoxy)ethoxide, and copper(II) 2-(2-methoxyethoxy)ethoxide. Examples of copper dithiocarbamate include copper(II) dimethyldithiocarbamate. Examples of salts of copper and inorganic acids include copper(II) nitrate, copper(II) bromide, and copper(II) chloride. These may be used alone or in combination of two or more. Among these, from the viewpoints of solubility and reactivity in polymerizable monomers and adhesion to tooth structure (especially adhesion durability to enamel), copper(II) carboxylate, β-diketone copper(II), β-ketoester copper(II), and salts of copper and inorganic acids are preferred, and copper(II) acetate, copper(II) acetylacetonate, and copper(II) bromide are particularly preferred.

[0051] The content of the copper compound (c-1) is preferably in the range of 0.0001 to 1 part by mass, more preferably in the range of 0.0002 to 0.5 parts by mass, and even more preferably in the range of 0.0003 to 0.2 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention, from the viewpoints of hardenability, mechanical strength of the hardened product obtained by chemical hardening, and adhesion to tooth structure (particularly adhesion durability to enamel).

[0052] The dental hardenable composition of the present invention has a copper atom concentration of 0.2 μg / g or more as determined by inductively coupled plasma mass spectrometry (ICP-MS). The copper atom concentration is 0.2 μg / g or more, and thus the catalytic activity is improved when coordinated with bromide salt (c-2), and the mechanical strength of the cured product is excellent. The copper atom concentration is preferably 0.23 μg / g or more, and more preferably 0.24 μg / g or more. The upper limit of the copper atom concentration is not particularly limited, but can be, for example, 30 μg / g or less. The copper atom concentration in the dental hardenable composition of the present invention is measured by ICP mass spectrometry using the measurement conditions described in the Examples below. In addition, in an embodiment in which the dental hardenable composition is packaged in a first agent and a second agent, when the first agent and the second agent are mixed, a hardening reaction proceeds, making it difficult to measure the copper atomic concentration in the composition. In such a case, the copper atomic concentration in each of the first agent and the second agent may be measured, and the sum of the copper atomic concentrations in each of the first agent and the second agent may be calculated as the copper atomic concentration in the dental hardenable composition.

[0053] The dental hardenable composition of the present invention contains a bromide salt (c-2) as a polymerization accelerator (c). However, in the present invention, copper bromide is defined as one of the copper compounds (c-1), and is therefore not included in the bromide salt (c-2). As mentioned above, by including bromide salt (c-2), when combined with copper compound (c-1), the reactivity of copper atom is improved by electron attraction by bromide ion, and the interaction between the copper compound having copper atom in a state of being coordinated and substituted by bromide ion and the polymerization initiator peroxide (b) is easily generated. As a result, chemical polymerization proceeds more efficiently, and the mechanical strength of the resulting cured product is improved. In addition, the peroxide (b) and the bromide salt (c-2) as a polymerization accelerator are consumed more efficiently in the polymerization reaction, and the polymerization reaction proceeds sufficiently at the interface between the hardened product of the dental hardenable composition and the tooth structure, resulting in less brittle hardened product at the interface. As a result, this acts in conjunction with the excellent adhesion to enamel provided by the polymerizable monomer (a) having an acidic group, resulting in excellent adhesion durability to enamel.

[0054] The bromide salt (c-2) may be an inorganic bromide or an organic bromide.

[0055] Examples of inorganic bromides include zinc bromide (ZnBr2), potassium bromide, sodium bromide, lithium bromide, calcium bromide, barium bromide, indium bromide, cobalt bromide, and bismuth bromide.

[0056] Examples of the organic bromides include bromides of quaternary ammonium ions and quaternary phosphonium ions. Specific examples of organic bromides include benzyltriethylammonium bromide, cetylpyridine bromide, cetyltriethylammonium bromide, mono- to tetraallylalkylammonium bromide, tetra-n-butyl-ammonium bromide (hereinafter sometimes abbreviated as "TBAB"), tetradecyltriethyl-ammonium bromide, tetraethylammonium bromide, dilauryldimethylammonium bromide, and benzyltriethylammonium bromide. As the bromide salt (c-2), zinc bromide, ammonium bromide, and tetra-n-butyl-ammonium bromide are particularly preferred, since they have improved catalytic activity upon coordination substitution and provide a cured product with superior mechanical strength obtained by chemical curing.

[0057] The content of the bromide salt (c-2) is preferably in the range of 0.005 to 2 parts by mass, more preferably in the range of 0.008 to 1.5 parts by mass, and even more preferably in the range of 0.01 to 1 part by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention, from the viewpoints of hardenability, mechanical strength of the hardened product obtained by chemical hardening, and adhesion to tooth structure (particularly adhesion durability to enamel).

[0058] The dental hardenable composition of the present invention has a bromine atom concentration of 20 μg / g or more as determined by the CIC measurement method. The bromine atom concentration is 20 μg / g or more, so that the coordination substitution with the copper compound proceeds more efficiently, resulting in excellent mechanical strength of the cured product. The bromine atom concentration is preferably 25 μg / g or more, more preferably 30 μg / g or more, and even more preferably 100 μg / g or more. The upper limit of the bromine atom concentration is not particularly limited, but can be, for example, 1500 μg / g or less. The bromine atom concentration in the dental hardenable composition of the present invention is measured by a CIC measurement method using the measurement conditions described in the Examples below. In addition, in embodiments in which the dental hardenable composition is divided into a first agent and a second agent, if it is difficult to measure the bromine atom concentration in the composition due to the hardening reaction that occurs when the first agent and the second agent are mixed, the bromine atom concentration may be calculated by measuring the first agent or the second agent and converting it into the total composition parts by mass of the first agent and the second agent combined.

[0059] In the dental hardenable composition of the present invention, the bromine atom concentration is higher than the copper atom concentration, so that bromide ions can be sufficiently coordinated to copper atoms as ligands, and interaction with peroxide (b) occurs easily. Therefore, the copper atom concentration determined by ICP mass spectrometry (ICP-MS) is 0.2 μg / g or more, and the bromine atom concentration determined by combustion ion chromatography (CIC) measurement method is 20 μg / g or more. Within the ranges of the copper atom concentration and the bromine atom concentration, the concentration ratio of the bromine atom concentration measured by the above-mentioned measuring method to the copper atom concentration (Br / Cu) is preferably at least 4. When the concentration ratio is at least 4, the coordination substitution between the copper compound and the bromide salt proceeds more efficiently, and as a result, the mechanical strength of the cured product obtained by chemical curing is excellent. From the viewpoint of adhesion to tooth structure (particularly adhesion durability to enamel), the concentration ratio (Br / Cu) is preferably 8 or more, more preferably 10 or more, and even more preferably 100 or more. The upper limit of the concentration ratio (Br / Cu) is not particularly limited, but can be set to, for example, 3000 or less.

[0060] The dental curable composition of the present invention may contain a polymerization accelerator other than the copper compound (c-1) and the bromide salt (c-2) having the function of the polymerization accelerator (c). The polymerization accelerator (c) may be used alone or in combination of two or more kinds.

[0061] Examples of the polymerization accelerator (c) include aromatic sulfinic acid compounds (c-3), amine reducing agents (c-4), and reducing inorganic compounds having sulfur (c-5). Specific examples thereof include the following:

[0062] In one preferred embodiment, the polymerization accelerator (c) further contains an aromatic sulfinic acid compound (c-3) from the viewpoints of mechanical strength of the cured product upon chemical curing of the hardenable composition and adhesion to tooth structure.

[0063] Examples of the aromatic sulfinic acid compound (c-3) include p-toluenesulfinic acid, sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic acid, sodium benzenesulfinate, potassium benzenesulfinate, lithium benzenesulfinate, calcium benzenesulfinate, 2,4,6-trimethylbenzenesulfinic acid, sodium 2,4,6-trimethylbenzenesulfinate, potassium 2,4,6-trimethylbenzenesulfinate, lithium 2,4,6-trimethylbenzenesulfinate, and 2,4,6-trimethylbenzenesulfinate. Examples of the sulfinic acid include calcium benzenesulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate, potassium 2,4,6-triethylbenzenesulfinate, lithium 2,4,6-triethylbenzenesulfinate, calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, calcium 2,4,6-triisopropylbenzenesulfinate, etc. Among these, sodium benzenesulfinate, sodium p-toluenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, and sodium 2,4,6-triisopropylbenzenesulfinate are particularly preferred.

[0064] It is preferable that at least a part of the aromatic sulfinic acid compound (c-3) is dispersed in the composition in a powder form. By dispersing in a powder form, the dental hardenable composition of the present invention can ensure a longer operation time, and when applied to a wet body such as a tooth, the aromatic sulfinic acid compound (c-3) dissolves in water on the surface of the wet body, so that the polymerizability at the adhesive interface and inside the resin-impregnated layer can be further increased. When the aromatic sulfinic acid compound (c-3) is dispersed in a powder form, it is preferable that the aromatic sulfinic acid compound (c-3) has a solubility in water at room temperature (25°C) of 1 mg / 100 mL or more. If the solubility is less than 1 mg / 100 mL, when the dental hardenable composition of the present invention is applied to a wet body, the aromatic sulfinic acid compound (c-3) does not dissolve sufficiently in the water of the wet body at the adhesive interface, and as a result, the effect of dispersing in powder is difficult to be expressed. In addition, if the aromatic sulfinic acid compound (c-3) has an excessively large particle size, it tends to settle, so the average particle size 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 may become excessively large, which may reduce the handleability of the dental curable composition, so the average particle size is preferably 0.01 μm or more. When dispersed in powder form, the average particle size is preferably in the range of 0.01 to 500 μm, more preferably in the range of 0.01 to 100 μm. In the present invention, the average particle size of the aromatic sulfinic acid compound (c-3) refers to the volume average particle size, and the volume average particle size can be calculated, for example, by performing image analysis using image analysis software (e.g., Mac-View; manufactured by Mountech Co., Ltd.) based on an electron microscope photograph of 100 or more particles.

[0065] The shape of the aromatic sulfinic acid compound (c-3) when dispersed in a powder state may be, but is not limited to, various shapes such as spherical, needle-like, plate-like, crushed, etc. The aromatic sulfinic acid compound (c-3) can be prepared into a fine powder by a conventionally known method such as a pulverization method or a freeze-drying method.

[0066] The content of the aromatic sulfinic acid compound (c-3) is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 4 parts by mass, and even more preferably 0.5 to 3 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the curable composition of the present invention. When the content is 0.1 parts by mass or more and 5 parts by mass or less, the mechanical strength and adhesion to tooth structure of the cured product obtained when the hardenable composition is chemically cured are superior.

[0067] One preferred embodiment is a dental hardenable composition in which the polymerization accelerator (c) further contains an amine reducing agent (c-4) from the viewpoint of adhesion to tooth structure. The amine reducing agent (c-4) is roughly classified into aromatic amines and aliphatic amines, and either aromatic amines or aliphatic amines may be used in the present invention. The amine reducing agent (c-4) may be used alone or in combination of two or more kinds.

[0068] As the aromatic amine, known aromatic secondary amines, aromatic tertiary amines, etc. may be used. Examples of the aromatic secondary amines or aromatic tertiary amines include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-di(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, and N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline. phosphorus, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, N,N-diethyl-p-toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, and N,N-dimethyl-3,5-di-t-butylaniline. Among these, N,N-di(2-hydroxyethyl)-p-toluidine is preferred in terms of redox reactivity.

[0069] Examples of aliphatic amines include aliphatic primary amines such as n-butylamine, n-hexylamine, and n-octylamine; aliphatic secondary amines such as diisopropylamine, dibutylamine, and N-methylethanolamine; and aliphatic tertiary amines such as N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl(meth)acrylate, N-methyldiethanolamine di(meth)acrylate, N-ethyldiethanolamine di(meth)acrylate, triethanolamine tri(meth)acrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, aliphatic tertiary amines are preferred from the viewpoint of redox reactivity, and among them, N-methyldiethanolamine, triethanolamine, and 2-(dimethylamino)ethyl methacrylate are particularly preferred.

[0070] From the viewpoint of adhesion to tooth structure, the content of the amine reducing agent (c-4) is preferably 0.01 to 10 parts by mass, more preferably 0.02 to 5 parts by mass, and even more preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention. When the content is 0.01 parts by mass or more, the adhesiveness of the resulting dental hardenable composition to tooth structure is superior, whereas when the content is 10 parts by mass or less, the color stability of the resulting dental hardenable composition is superior.

[0071] A preferred embodiment of the present invention is a dental hardenable composition, in which the polymerization accelerator (c) further contains a sulfur-containing reducing inorganic compound (c-5) from the viewpoints of the mechanical strength of the hardened product upon chemical hardening of the hardenable composition and adhesion to tooth structure.

[0072] Examples of the sulfur-containing reducing inorganic compound (c-5) include sulfites, bisulfites, pyrosulfites, thiosulfates, thionates, and dithionites, and among these, sulfites and bisulfites are preferred. Specific examples of the sulfur-containing reducing inorganic compound (c-5) include sodium sulfite, potassium sulfite, calcium sulfite, ammonium sulfite, sodium hydrogen sulfite, and potassium hydrogen sulfite. The sulfur-containing reducing inorganic compound (c-5) may be used alone or in combination of two or more kinds.

[0073] The reducing inorganic compound (c-5) having sulfur is preferably at least partially dispersed in the composition in powder form.By dispersing in powder form, the dental hardenable composition of the present invention can secure a longer operation time, and when applied to tooth substance, the reducing inorganic compound (c-5) having sulfur dissolves in the water on the tooth substance surface, so that the polymerizability at the adhesive interface and inside the resin-impregnated layer can be further increased. When the reducing inorganic compound (c-5) having sulfur is dispersed in a powder state, the reducing inorganic compound (c-5) having sulfur preferably has a solubility in water of 1 mg / 100 mL or more at room temperature (25° C.). If the solubility is less than 1 mg / 100 mL, when the dental hardenable composition of the present invention is applied to a tooth, the reducing inorganic compound (c-5) having sulfur does not dissolve sufficiently in the water of the tooth at the adhesive interface, and as a result, the effect of dispersing in powder is difficult to be exhibited. Furthermore, since the sulfur-containing reducing inorganic compound (c-5) is prone to settling if its particle size is too large, the average particle size 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, which may reduce the handleability of the dental curable composition, so the average particle size is preferably 0.01 μm or more. When dispersed in a powder state, the average particle size is preferably in the range of 0.01 to 500 μm, more preferably in the range of 0.01 to 100 μm. The average particle size of the sulfur-containing reducing inorganic compound (c-5) can be measured in the same manner as the average particle size of the aromatic sulfinic acid compound (c-3).

[0074] The shape of the sulfur-containing reducing inorganic compound (c-5) when dispersed in a powder state may be, but is not limited to, various shapes such as spherical, needle-like, plate-like, crushed, etc. The sulfur-containing reducing inorganic compound (c-5) can be prepared into a fine powder by a conventionally known method such as a pulverization method or a freeze-drying method.

[0075] The content of the sulfur-containing reducing inorganic compound (c-5) is preferably 0.01 to 15 parts by mass, more preferably 0.05 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental curable composition of the present invention. When the content is 0.01 parts by mass or more, the adhesiveness of the resulting dental hardenable composition to tooth structure is superior, whereas when the content is 15 parts by mass or less, the mechanical strength of the cured product obtained by chemical hardening of the dental hardenable composition is superior.

[0076] The dental hardenable composition of the present invention may further contain a filler (d) in order to obtain sufficient workability of the composition and sufficient radiopacity and mechanical strength of the cured product.

[0077] As the filler (d), any filler can be used as long as it does not impair the effects of the present invention, and examples of such fillers include inorganic fillers, organic fillers, and composite fillers of inorganic fillers and organic fillers. The filler (d) may be used alone or in combination of two or more kinds. The average particle size of the filler (d) is preferably 0.001 to 10 μm, and more preferably 0.001 to 5 μm.

[0078] Inorganic fillers include silica; silica-based minerals such as kaolin, clay, mica, and mica; and silica-based ceramics and glasses containing Al2O3, B2O3, TiO2, ZrO2, BaO, La2O3, SrO, ZnO, CaO, P2O5, Li2O, Na2O, etc. Examples of glasses include lithium borosilicate glass, borosilicate glass, bioglass, lanthanum glass, barium glass, strontium glass, soda glass, zinc glass, and fluoroaluminosilicate glass. As the inorganic filler, crystalline quartz, hydroxyapatite, alumina, titanium oxide, yttrium oxide, zirconia, barium sulfate, aluminum hydroxide, sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, ytterbium fluoride, and the like can also be suitably used. From the standpoint of adhesiveness and ease of handling, it is preferable that the adhesive contains finely divided silica having an average particle size of 0.001 to 1 μm.

[0079] As the inorganic filler, commercially available products may be used. Commercially available products include "Aerosil (registered trademark) OX50", "Aerosil (registered trademark) 50", "Aerosil (registered trademark) 200", "Aerosil (registered trademark) 380", "Aerosil (registered trademark) R972", "Aerosil (registered trademark) 130", and "AEROXIDE (registered trademark) Alu C" (all of which are product names manufactured by Nippon Aerosil Co., Ltd.). In the present invention, when the inorganic filler is surface-treated as described below, the average particle size of the inorganic filler means the average particle size before the surface treatment.

[0080] Examples of the organic filler include polymethyl methacrylate, polyethyl methacrylate, polyfunctional methacrylate polymers, polyamide, polystyrene, polyvinyl chloride, chloroprene rubber, nitrile rubber, and styrene-butadiene rubber.

[0081] Examples of composite fillers of inorganic and organic fillers include those in which inorganic fillers are dispersed in organic fillers, and inorganic-organic composite fillers in which inorganic fillers are coated with various polymers.

[0082] In order to improve the curability, mechanical strength and handling of the cured product, the filler (d) may be surface-treated with a known surface treatment agent such as a silane coupling agent before use. For example, the silane coupling agent (e) described below may be used as the surface treatment agent. Examples of the surface treatment agent include silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-(meth)acryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. When the filler (d) is surface-treated, the average particle size of the filler (d) represents the average particle size of the particles before the surface treatment.

[0083] The average particle size (average primary particle size) of the filler (d) can be determined by the laser diffraction scattering method or by observing the particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, while the electron microscope observation is convenient for measuring the particle size 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 is used as a dispersion medium and the measurement can be performed on a volume basis using a laser diffraction particle size distribution measuring device (SALD-2300, manufactured by Shimadzu Corporation). For electron microscope observation, a scanning electron microscope (SU3800, S-4000, etc., manufactured by Hitachi High-Technologies Corporation) can be used. For electron microscope observation, an electron microscope photograph of the particles is taken, and the particle diameters of the particles (200 or more) observed within a unit field of view of the photograph can be determined by using image analysis type particle size distribution measurement software (Mac-View, manufactured by Mountec Co., Ltd.). In this case, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average primary particle diameter is calculated from the number of particles and their particle diameters.

[0084] The content of the filler (d) is not particularly limited as long as the effects of the present invention are exhibited, but is preferably in the range of 30 to 800 parts by mass, more preferably in the range of 50 to 300 parts by mass, and even more preferably in the range of 100 to 250 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components of the dental curable composition of the present invention. Within these ranges, sufficient X-ray opacity or sufficient mechanical strength of the cured product can be obtained, and sufficient paste operability can be obtained.

[0085] The dental curable composition of the present invention may further contain a silane coupling agent (e). The silane coupling agent (e) may be contained alone or in combination of two or more kinds. As the silane coupling agent (e), for example, any known silane coupling agent satisfying the following general formula (5) can be used without limitation.

[0086] [ka] (In the formula, Y 1 represents an organic group having 1 to 20 carbon atoms and having at least one functional group selected from the group consisting of a (meth)acryloyloxy group, a vinyl group, and an epoxy group, or a functional group selected from the group consisting of an acryloyloxy group, a vinyl group, and an epoxy group; Y 2 represents a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, or an alkoxy group having 1 to 5 carbon atoms; Y 3 , Y 4 each represents a hydroxyl group or an alkoxy group having 1 to 5 carbon atoms; Y 2 ~Y 4 At least one of the groups is an alkoxy group having 1 to 5 carbon atoms.)

[0087] Y 1 The organic group of Y is not particularly limited, and examples thereof include saturated or unsaturated aliphatic, cycloaliphatic, or aromatic hydrocarbon groups. 1 As the organic group of Y, among these, an alkylene group having 3 to 15 carbon atoms is particularly preferable, an alkylene group having 5 to 15 carbon atoms is more preferable, and an alkylene group having 6 to 14 carbon atoms is further preferable. 1The organic group functions as a spacer moiety with a long carbon chain length, resulting in superior hydrophobicity and superior adhesion durability to enamel. Also, Y 1 The organic group of Y may have a substituent that does not contain a carbon atom, such as a halogen atom, a hydroxyl group, an amino group, a mercapto group, a cyano group, or a nitro group. 1 The organic group may contain, in its structure, bonds other than carbon-carbon bonds, such as ether bonds, ester bonds, amide bonds, sulfonyl bonds, urethane bonds, and thioether bonds.

[0088] Y 2 The alkyl group may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a cyclopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclobutyl group, and an n-pentyl group. Y 2 , Y 3 , and Y 4 The alkoxy group may be linear, branched, or cyclic, and examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, and a tert-butoxy group.

[0089] Specific examples of the silane coupling agent (e) include vinyl group-containing silane coupling agents such as vinyltriethoxysilane, vinyltris(β-methoxyethoxy)silane, vinyltripoxysilane, and vinyltributoxysilane; and (meth)acryloyloxy group-containing silane coupling agents such as γ-(meth)acryloyloxypropyltriethoxysilane, γ-(meth)acryloyloxypropyltris(β-methoxyethoxy)silane, 6-(meth)acryloyloxyhexyltriethoxysilane, κ-methacryloyloxydecyltriethoxysilane, 11-(meth)acryloyloxyundecyltriethoxysilane, and 11-(meth)acryloyloxyundecyltrimethoxysilane.

[0090] From the viewpoint of handleability, the content of the silane coupling agent (e) is preferably from 0.1 to 15.0 mass %, and more preferably from 0.5 to 10.0 mass %, based on the total mass of the dental curable composition.

[0091] The dental hardenable composition of the present invention contains a redox type polymerization initiator, but in order to make it a dual cure type composition that also initiates polymerization by light irradiation, or to make it a kit with a dental adhesive that initiates polymerization by light irradiation, the dental hardenable composition may further contain a conventionally known photopolymerization initiator as a component separate from the above-mentioned polymerization initiator system.

[0092] Examples of the photopolymerization initiator include α-diketones, ketals, thioxanthones, (bis)acylphosphine oxides, and α-aminoacetophenones.

[0093] Examples of α-diketones include dl-camphorquinone (hereinafter sometimes abbreviated as "CQ"), benzil, and 2,3-pentanedione.

[0094] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0095] Examples of thioxanthones include 2-chlorothioxanthone and 2,4-diethylthioxanthone.

[0096] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, benzoylbis(2,6-dimethylphenyl)phosphine oxide, water-soluble acylphosphine oxide compounds disclosed in JP-B-3-57916, and salts thereof (for example, sodium salts, potassium salts, ammonium salts), and the like. Examples of bisacylphosphine oxides include bis(2,4,6-trimethylbenzoyl)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, dibenzoylphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, tris(2,4-dimethylbenzoyl)phosphine oxide, tris(2-methoxybenzoyl)phosphine oxide, and salts thereof (e.g., sodium salts, potassium salts, ammonium salts), and the like. Among these (bis)acylphosphine oxides, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide and 2,4,6-trimethylbenzoylphenylphosphine oxide sodium salt are preferred.

[0097] Examples of α-aminoacetophenones include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-butanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-propanone, 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-1-pentanone, and 2-benzyl-2-diethylamino-1-(4-morpholinophenyl)-1-pentanone.

[0098] In order to enhance the photocurability, a photopolymerization initiator and a polymerization accelerator for the photopolymerization initiator may be used in combination with the peroxide (b). Examples of the polymerization accelerator used together with the photopolymerization initiator include aldehydes, thiol compounds, triazine compounds substituted with a trihalomethyl group, benzotriazole compounds, benzimidazole compounds, borate compounds, and barbituric acid compounds. The polymerization accelerator for the photopolymerization initiator may be used alone or in combination of two or more kinds.

[0099] Certain embodiments include dental hardenable compositions that are free of barbiturates. Certain other embodiments include dental hardenable compositions that are free of benzotriazole and benzimidazole compounds.

[0100] Examples of the aldehydes include terephthalaldehyde and benzaldehyde derivatives. Examples of the benzaldehyde derivatives include dimethylaminobenzaldehyde, p-methoxybenzaldehyde, p-ethoxybenzaldehyde, and pn-octyloxybenzaldehyde. Examples of the thiol compound include 3-mercaptopropyltrimethoxysilane, 2-mercaptobenzoxazole, 2-mercaptobenzimidazole, decanethiol, and thiobenzoic acid. As the trihalomethyl-substituted triazine compound, any known s-triazine compound having at least one trihalomethyl group such as a trichloromethyl group or a tribromomethyl group can be used without any limitation.

[0101] Examples of the benzotriazole compound include 1H-benzotriazole (hereinafter sometimes abbreviated as "BTA"), 5-methyl-1H-benzotriazole, and 5,6-dimethyl-1H-benzotriazole. Examples of the benzimidazole compound include benzimidazole, 5-methylbenzimidazole, and 5,6-dimethylbenzimidazole. Examples of the borate compound include aryl borate compounds and their salts, etc. Examples of the aryl borate compound include aryl borate compounds having 1 to 4 aryl groups in one molecule (e.g., tetraphenyl boron, tetrakis(p-chlorophenyl) boron, etc.) and their salts, etc. Examples of barbituric acid and its derivatives include barbituric acid, 5-butylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and salts thereof.

[0102] The dental hardenable composition of the present invention may further contain a fluoride ion releasing substance. By blending the fluoride ion releasing substance, a dental cement capable of imparting acid resistance to tooth structure can be obtained. Examples of the fluoride ion releasing substance include fluoride ion releasing polymers such as copolymers of methyl methacrylate and methacrylic acid fluoride; hydrofluorides of aliphatic or alicyclic primary, secondary or tertiary amines such as cetylamine hydrofluoride, cyclohexylamine hydrofluoride, diisobutylamine hydrofluoride, and triethylamine trihydrofluoride; and metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride. The fluoride ion releasing substance may be used alone or in combination of two or more.

[0103] In addition, the dental curable composition of the present invention may contain a polymerization inhibitor, a pH adjuster, an ultraviolet absorber, an organic solvent, a solvent such as water, a thickener, a colorant, an antibacterial agent, a fragrance, etc., within the range that does not impair the effects of the present invention. Each of these may be used alone or in combination of two or more.

[0104] 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 2,6-di-t-butyl-4-methylphenol.

[0105] The content of the polymerization inhibitor is preferably 0.001 to 1.0 part by mass relative to 100 parts by mass of the total amount of the polymerizable monomers in the dental curable composition.

[0106] 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 hardenable composition is preferably substantially free of water from the viewpoint of achieving the effects of the present invention. The dental hardenable composition being "substantially free of water" means that the water content is preferably less than 1 mass%, more preferably 0.1 mass% or less, and even more preferably 0.01 mass% or less, based on the total mass of the dental hardenable composition, and may be 0 mass%.

[0107] The dental curable composition of the present invention may be prepared according to a conventional method depending on the components contained therein. The dental curable composition of the present invention is preferably used in a packaged form (preferably a two-part form), and can be implemented by appropriately selecting from a powder and liquid form, a paste and liquid form, a two-paste form, etc. From the viewpoint of operability, in a more preferred embodiment, the filler is used in the form of a two-paste type. It is preferable to store each paste in a state where the pastes are isolated from each other, and to knead the two pastes immediately before use and allow chemical polymerization to proceed and harden them. The paste is usually prepared by kneading a liquid component prepared by mixing components other than the filler (d) with the filler (d) (powder).

[0108] As described above, in the dental hardenable composition of the present invention, the polymerizable monomer (a) having an acidic group, the peroxide (b), the copper compound (c-1), and the bromide salt (c-2) interact with each other, and the hardened product upon chemical hardening has excellent mechanical strength and excellent adhesion durability to enamel. When the dental hardenable composition of the present invention is in the form of a separate package (preferably a two-part type), the blending of each component is not limited as long as the components do not interfere with each other's effects and can react upon use. If the three components, peroxide (b), copper compound (c-1), and bromide salt (c-2), are all contained in either the first or second agent, a reaction will begin, so it is preferable to package these components separately. A preferred embodiment (X-1) includes a first agent and a second agent, The dental hardenable composition includes a first agent containing a peroxide (b) and a copper compound (c-1), and a second agent containing a bromide salt (c-2). Another preferred embodiment (X-2) includes a first agent and a second agent, The dental hardenable composition includes a first agent containing a peroxide (b) and a bromide salt (c-2), and a second agent containing a copper compound (c-1). Another preferred embodiment (X-3) includes a first agent and a second agent, The dental hardenable composition includes a dental hardenable composition in which the first agent contains a copper compound (c-1) and the second agent contains a peroxide (b) and a bromide salt (c-2). Another preferred embodiment (X-4) includes a first agent and a second agent, The dental hardenable composition includes a dental hardenable composition in which the first agent contains a peroxide (b), and the second agent contains a copper compound (c-1) and a bromide salt (c-2). In the above-mentioned preferred embodiments (X-1) to (X-4), the copper atom concentration and the bromine atom concentration can be appropriately changed within the ranges described in this specification. In the above-mentioned preferred embodiments (X-1) to (X-4), the polymerizable monomer (a) having an acidic group may be blended in either the first agent or the second agent, or may be blended in the first agent. In particular, from the viewpoint of excellent storage stability of the dental curable composition, in the above-mentioned preferred embodiments (X-1) to (X-4), it is preferable that the polymerizable monomer (a) having an acidic group and the copper compound (c-1) are contained in the same agent. For example, in the embodiment (X-1), when the polymerizable monomer (a) having an acidic group is contained, The composition includes a first agent and a second agent, the first agent contains a polymerizable monomer (a) having an acidic group, a peroxide (b), and a copper compound (c-1); The dental hardenable composition may include a dental hardenable composition in which the second agent contains a bromide salt (c-2). Furthermore, optional components such as an aromatic sulfinic acid compound (c-3), an amine-based reducing agent (c-4), a sulfur-containing reducing inorganic compound (c-5), a filler (d), a silane coupling agent (e), and a polymerization inhibitor may be blended into either the first agent and / or the second agent as necessary. For example, in the above-mentioned preferred embodiments (X-1) to (X-4), when the first agent contains the polymerizable monomer (a) having an acidic group, it is preferable that the aromatic sulfinic acid compound (c-3), the amine reducing agent (c-4), and / or the sulfur-containing reducing inorganic compound (c-5) are blended in the second agent in order to provide a dental curable composition with excellent storage stability. In another embodiment, the peroxide (b), the copper compound (c-1), and the bromide salt (c-2) may be packaged separately as a three-dose formulation.

[0109] The dental curable composition of the present invention is used for bonding dental prostheses such as crowns, inlays and bridges to tooth structures at defective areas of affected teeth, and for constructing abutments. The dental curable composition of the present invention can be used, for example, as a dental cement (dental resin cement, etc.), a dental adhesive, a dental composite resin (self-adhesive composite resin, etc.), a sealant, a dental self-polymerizing resin, etc. In particular, it is preferably used as a dental resin cement.

[0110] The present invention includes embodiments in which the above-described 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

[0111] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. The abbreviations and symbols used below are as follows. The compounds and fillers used in the following examples and comparative examples were commercially available products, except when the production method was specifically described.

[0112] [Polymerizable monomer (a) having an acidic group] MDP: 10-methacryloyloxydecyl dihydrogen phosphate

[0113] [Polymerizable monomer having no acidic group] HEMA: 2-hydroxyethyl methacrylate Bis-GMA: 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6) TEGDMA: Triethylene glycol dimethacrylate NPG: Neopentyl glycol dimethacrylate

[0114] [Organic peroxide (b-1)] BPB: t-Butyl peroxybenzoate

[0115] [Inorganic peroxide (b-2)] KPS: Potassium peroxodisulfate

[0116] [Copper compound (c-1)] CA: Copper(II) acetate CuBr2: Copper(II) bromide

[0117] [Bromide salt (c-2)] TBAB: Tetra-n-butyl-ammonium bromide ZnBr2: Zinc bromide NH4Br: Ammonium bromide

[0118] [Aromatic sulfinic acid compounds (c-3)] TPBSS: Sodium 2,4,6-triisopropylbenzenesulfinate

[0119] [Amine reducing agents (c-4)] DEPT: N,N-di(2-hydroxyethyl)-p-toluidine

[0120] [Sulfur-containing reducing inorganic compounds (c-5)] Na2SO3: Sodium sulfite was pulverized in a vibration ball mill to adjust the average particle size to 6.1 μm. The average particle size was calculated as the volume average particle size after image analysis using image analysis software (Mac-View; manufactured by Mountec Co., Ltd.) based on electron micrographs of 100 or more particles.

[0121] [Filler (d)] Surface treatment Ba glass: Barium glass (manufactured by Estec Co., Ltd., product code "E-3000") was pulverized in a ball mill to obtain barium glass powder. The average particle size of the obtained barium glass powder was measured using a laser diffraction type particle size distribution measuring device (manufactured by Shimadzu Corporation, model "SALD-2300") and found to be 2.4 μm. 100 parts by mass of this barium glass powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method to obtain a surface-treated Ba glass powder. silica: Fumed silica (manufactured by Nippon Aerosil Co., Ltd., product name "Aerosil (registered trademark) 130", average particle size: 16 nm) was subjected to a surface treatment to prepare the powder. Specifically, 100 parts by mass of the fumed silica was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane in a conventional manner to obtain silane-treated fumed silica. R972: Fine particle silica manufactured by Nippon Aerosil Co., Ltd., product name "Aerosil (registered trademark) R972", average particle size: 16 nm Alumina: Aluminum oxide, manufactured by Nippon Aerosil Co., Ltd., trade name "AEROXIDE (registered trademark) Alu C", average particle size: 13 nm

[0122] [Silane coupling agent (e)] 11-MUS: 11-methacryloyloxyundecyltrimethoxysilane

[0123] [Polymerization inhibitor] BHT: 2,6-di-t-butyl-4-methylphenol

[0124] 〔others〕 CQ: Camphorquinone TMDPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide BTA: 1H-benzotriazole PDE: Ethyl 4-(N,N-dimethylamino)benzoate (polymerization accelerator for photopolymerization initiator) TBAI: Tetrabutylammonium iodide BZC: Benzalkonium chloride

[0125] [Quantification of copper atomic concentration using inductively coupled plasma mass spectrometry (ICP-MS)] The copper atom concentration in the dental hardenable composition of each of the Examples and Comparative Examples was quantified by the following method. 20 mg of the dental hardenable composition was weighed into a Teflon (registered trademark) decomposition container, high-purity nitric acid was added, and the container was sealed. Microwaves were irradiated using a microwave sample decomposition device (manufactured by Milestone General, product name "UltraWAVE") to perform pressure decomposition at a maximum temperature of 250°C and a maximum pressure of 70 to 80 bar. Thereafter, ultrapure water purified using an ultrapure water apparatus manufactured by Merck Ltd. was added to the sample to make up a total volume of 20 mL, which was used as a test liquid. The copper atom concentration in the dental hardenable composition was quantified using argon plasma with an inductively coupled plasma mass spectrometer (triple quadrupole ICP-MS, product name "Agilent 8800 ICP QQQ") manufactured by Agilent Technologies (USA) under the following conditions.

[0126] <Measurement conditions> Scan mode: MS / MS mode Cell Mode:Reaction Mode Reaction gas: He Cell reaction gas flow rate: 9.0mL / min Octopole bias: -100V Octopole RF:200V Cell output: -150V Deflection lens: -80.0V Plate bias: -150V KED:5.0V Plasma conditions: Set "low matrix" using the preset plasma conditions of ICP-MS Mass Hunter (hot plasma conditions (CeO + / Ce + Ratio: Less than 1% Plasma treatment carrier gas: 700mL / min Plasma treatment make-up gas: 500mL / min

[0127] [Quantification of bromine atom concentration using CIC] The bromine atom concentration in each of the dental hardenable compositions of the Examples and Comparative Examples was quantified by the following method. 10 mg of dental hardenable composition was collected on a ceramic board and weighed, then a combustion improver was added to obtain a sample. Next, the sample was burned using an automatic sample combustion device (pretreatment device for ion chromatoglobulin, Nitto Seiko Analytech Co., Ltd., product name "AQF-2100H", gas used: Ar, oxygen with a purity of 99.7% or more, 0.3±0.1 MPa), and the gas generated by combustion was collected in 10 ml of absorption liquid. The absorption liquid was ultrapure water with a reducing agent added.

[0128] The gas was collected by an absorption liquid, and the absorption liquid was then adjusted to 15 mL with pure water, and the bromine atom concentration of the liquid was quantified under the following conditions using an IC (manufactured by Thermo Fisher Scientific Inc. (US), product name "Dionex (registered trademark) ICS-5000 HPIC system"). <Measurement conditions> Anion analysis column: IonPac AS12A Guard column: IonPac AG12A Column temperature: 45℃ Dilution ratio: 15 times Sample injection volume: 10 μL Detector: Electrical conductivity detector (with suppressor)

[0129] [Examples 1 to 10 and Comparative Examples 1 to 7] Using a dental hardenable composition packaged in a first part and a second part containing the components shown in Table 1 below, each evaluation was carried out by each of the following methods.

[0130] [Flexural strength of cured product after chemical curing] For each of the dental hardenable compositions of the Examples and Comparative Examples, the bending strength of the cured product after chemical hardening was evaluated by the following method. A polyester film was laid on a slide glass plate, and a stainless steel mold frame measuring 2 mm in length, 25 mm in width, and 2 mm in depth was placed on top of the polyester film. Next, the mold was filled with a composition obtained by kneading the first and second parts shown in Table 1 below at a mass ratio of 1:1. The top and bottom surfaces of the composition in the mold were pressed against two slide glasses via polyester film, and the two slide glasses were fixed using a double clip with a width of 25 mm to obtain a sample. The sample fixed with the double clips was left to stand in an incubator at 37° C. for 1 hour to polymerize and harden the composition, and then the sample was removed from the incubator and the hardened composition was removed from the mold. The cured product was immersed in distilled water at 37°C for 24 hours and then used as a test piece to measure bending strength. The bending strength was measured in a three-point bending test using a universal testing machine (Shimadzu Corporation, product name "Autograph AG-I") with a span (distance between supports) of 20 mm and a crosshead speed of 1 mm / min. The average value of the bending strengths for the five test pieces was regarded as the bending strength of the cured product after chemical curing for that test piece. The flexural strength of the cured product after chemical curing is preferably 105 MPa or more, more preferably 108 MPa or more, and even more preferably 110 MPa or more.

[0131] [Adhesion to enamel (initial adhesion, adhesion durability)] The labial surface of a bovine mandibular anterior tooth was polished with silicon carbide paper under running water to expose the flat surface of the dentin. The exposed flat surface was further polished with #1000 silicon carbide paper under running water. After polishing, the water on the surface was dried by air blowing. After drying, an adhesive tape with a thickness of approximately 150 μm and a circular hole with a diameter of 3 mm was attached to the smooth surface to determine the adhesive area. The first and second parts of the dental hardenable composition were mixed in a mass ratio of 1:1 to prepare a composition. The composition was piled up on one end face (circular cross section) of a stainless steel cylindrical rod (diameter 7 mm, length 2.5 cm). Next, the end face on which the composition was piled up was placed on the smooth surface (adhering surface) in the circular hole so that the center of the circular hole and the center of the cylindrical rod were approximately aligned, and the stainless steel cylindrical rod was pressed perpendicularly against the smooth surface to adhere to the smooth surface, thereby preparing a test sample. Ten test samples were prepared. After removing the excess composition that had protruded from the stainless steel cylindrical rod when pressed, the samples were left to stand at room temperature for 30 minutes and then immersed in distilled water. The samples were left to stand for 24 hours immersed in distilled water in an incubator maintained at 37°C to prepare samples for evaluating initial adhesion. For five out of ten samples for evaluating initial adhesion, the tensile adhesive strength to enamel was measured as the initial adhesion. In addition, the remaining five out of the ten samples for evaluating initial adhesion were subjected to a thermal cycle (TC) load by alternately immersing them in a 4°C water bath and a 60°C water bath for one minute each 4,000 times to prepare samples for evaluating adhesion durability. The tensile adhesive strength to enamel was measured as an indication of adhesion durability. The tensile bond strength was measured using a universal testing machine (Shimadzu Corporation, product name "Autograph AG-I") with a crosshead speed set to 2 mm / min, and the average value of the measured values ​​for five samples was calculated. In the table, "initial adhesion" represents the tensile adhesion strength as the initial adhesion to the enamel, and "adhesion durability" represents the tensile adhesion strength to the enamel after 4,000 thermal cycles (TC). The tensile bond strength to enamel as an indication of adhesion durability is preferably 10 MPa or more, more preferably 11 MPa or more, and even more preferably 12 MPa or more.

[0132] [Table 1]

[0133] As shown in Table 1, the dental hardenable compositions of the present invention (Examples 1 to 10) had adhesion durability to enamel of 11 MPa or more, and the cured products upon chemical hardening had bending strengths of 105 MPa or more.

[0134] In contrast, in Comparative Examples 1 to 3, the flexural strength of the cured products after chemical curing was less than 105 MPa. In Comparative Example 4, the bending strength of the cured product after chemical curing was 116 MPa, but the adhesion durability to enamel was only 2.2 MPa. In Comparative Example 5, the bending strength of the cured product after chemical curing was 78 MPa, and the adhesion durability to enamel was 5.8 MPa. In Comparative Examples 6 and 7, the bending strength of the cured product after chemical curing was 70 MPa or less, and the adhesion durability to enamel was 4.4 MPa or less. From the results of Comparative Examples 6 and 7, it was confirmed that when a halide other than the bromide salt (c-2) was used, it was not possible to achieve both the effect of improving the catalytic activity of the copper compound by coordination to the copper atom and the occurrence of interaction with the peroxide (b), and in addition, the mechanical strength of the cured product upon chemical curing was inferior. In addition, due to insufficient interaction with the peroxide (b), the polymerization reaction did not proceed sufficiently at the interface between the cured product of the dental hardenable composition and the tooth structure, and the adhesion durability was reduced by 50% or more from the initial adhesion value. [Industrial Applicability]

[0135] The dental curable composition of the present invention can be particularly suitably used in dental treatment for bonding dental prostheses such as crowns, inlays and bridges to tooth structures, and for constructing abutments.

Claims

1. A dental curable composition comprising a polymerizable monomer (a) having an acidic group, a peroxide (b), and a polymerization accelerator (c), wherein the polymerization accelerator (c) contains a copper compound (c-1) and a bromide salt (c-2) (excluding copper bromide), the copper atom concentration quantified by ICP mass spectrometry (ICP-MS) is 0.2 μg / g or more, and the bromine atom concentration quantified by combustion ion chromatography (CIC) measurement is 20 μg / g or more.

2. The dental curable composition according to claim 1, wherein the polymerization accelerator (c) further contains an aromatic sulfinic acid compound (c-3).

3. The dental curable composition according to claim 1 or 2, wherein the polymerizable monomer (a) having an acidic group contains at least one selected from the group consisting of a polymerizable monomer having a phosphate group, a polymerizable monomer having a carboxylic acid group, and a polymerizable monomer having a sulfonic acid group.

4. The dental curable composition according to claim 1 or 2, wherein the peroxide (b) contains an organic peroxide (b-1).

5. The dental curable composition according to claim 1 or 2, wherein the polymerization accelerator (c) further contains an amine-based reducing agent (c-4).

6. The dental curable composition according to claim 1 or 2, wherein the polymerization accelerator (c) further contains a reducing inorganic compound (c-5) having sulfur.

7. The dental curable composition according to claim 1 or 2, further comprising a polymerizable monomer having no acidic group.

8. The dental curable composition according to claim 1 or 2, further comprising a filler (d).

9. The dental curable composition according to claim 1 or 2, further comprising a silane coupling agent (e).

10. comprising a first agent and a second agent, wherein the first agent contains a polymerizable monomer (a) having the acidic group, the peroxide (b), and the copper compound (c-1), The dental curable composition according to claim 1 or 2, wherein the second agent contains the bromide salt (c-2).