Dental composition, method for manufacturing same, and dental surface-treated filler

Abstract

The present invention provides: a dental composition that has excellent storage stability even under extreme conditions and in which a cured product thereof has sufficient mechanical strength; a method for manufacturing said dental composition; and a dental surface-treated filler. The present invention pertains to a dental composition containing a polymerizable monomer (A), a polymerization initiator (B), and a filler (C). The filler (C) contains a dental surface-treated filler (C-1) surface-treated by an end capping agent (b) and a silane coupling agent (a) having a polymerizable group. The metal component elution amount in an acid resistance test of the dental surface-treated filler (C-1) is below 100 ppm.

Description

Dental composition, method for producing same, and dental surface treatment filler

[0001] The present invention relates to a dental composition. More specifically, the present invention relates to a dental composition that has excellent storage stability even under severe conditions and a cured product thereof that has sufficient mechanical strength, a method for producing the same, and a dental surface-treating filler.

[0002] In the treatment of dental caries and associated defects, restorative treatment using dental bonding materials and dental composite resins has traditionally been commonly performed. This restorative treatment involves the following steps: First, a cavity is formed by removing the carious area, and then a dental adhesive is applied to the cavity. If necessary, the solvent is removed using an air blower or other method. Visible light is then irradiated onto the applied area to harden the dental bonding material. Next, dental composite resin is applied onto the hardened dental bonding material layer, and finally, the applied dental composite resin is irradiated with visible light to harden it.

[0003] In the restorative treatment described above, two materials are used: a dental bonding material and a dental composite resin. However, recently, a self-adhesive dental composite resin, which is a dental composite resin with adhesive properties, has been developed and is beginning to be put into practical use as a material that eliminates the need for a dental bonding material and reduces the number of operational steps in restorative treatment.

[0004] Self-adhesive dental composite resins contain, in addition to the components also contained in conventional dental composite resins, such as polyfunctional polymerizable monomers, fillers, and polymerization initiators, polymerizable monomers having acidic groups such as phosphate groups or carboxy groups, which are used in dental bonding materials, etc., for the purpose of imparting and improving self-adhesion to tooth structures, etc. (See, for example, Patent Document 1, etc.).

[0005] On the other hand, when an oxide, carbonate, or hydroxide of an alkaline earth metal such as barium or strontium, or an acid-reactive fluoroaluminosilicate glass, which are commonly used as fillers in dental composite resins, is blended into a self-adhesive dental composite resin such as that described in Patent Document 1, an acid-base reaction, neutralization, salt formation, or chelate reaction occurs between the filler and a polymerizable monomer having an acidic group. As a result, the polymerizable monomer having an acidic group is consumed, and the self-adhesiveness itself is impaired. This is a known issue between the specific filler and the polymerizable monomer having an acidic group.

[0006] Furthermore, this problem generally occurs in dental hardenable compositions containing the above-mentioned specific filler and a polymerizable monomer having an acidic group. Therefore, various dental hardenable compositions have been proposed to address this problem (see, for example, Patent Documents 2 to 4). Patent Document 2 discloses a one-component self-adhesive dental composition containing a filler that has low reactivity with acidic components, such as a silica filler treated with a silane coupling agent.

[0007] In addition, Patent Document 3 discloses a dental composition that has excellent storage stability even when it contains inorganic particles containing a polymerizable monomer having an acidic group and a polyvalent metal, by subjecting inorganic particles containing a polyvalent metal to an acid treatment process to reduce the amount of polyvalent metal on the inorganic particle surface.In addition, Patent Document 4 discloses a self-adhesive dental composite resin that maintains mechanical strength and exhibits excellent storage stability by blending inorganic particles that have been surface-treated with a silane coupling agent of a specific structure and an organosilazane of a specific structure, and that exhibits little change in paste transparency and properties during long-term storage and has a low risk of solidification.

[0008] JP 2008-260752 A JP 2015-507610 A JP 2011-178778 A WO 2018 / 074594

[0009] However, after investigations by the present inventors, it was found that the one-component self-adhesive dental composition disclosed in Patent Document 2, which contains silica filler and the like surface-treated with a general silane coupling agent, does not provide sufficient storage stability.

[0010] Furthermore, although the acid treatment disclosed in Patent Document 3 has a certain effect on storage stability, there is room for further improvement under more severe conditions (for example, 60° C. for 4 weeks).

[0011] Furthermore, with regard to the specific surface treatment disclosed in Patent Document 4, when a silica filler was treated, relatively excellent effects were obtained in terms of paste properties such as paste transparency with respect to the storage stability of a self-adhesive dental composite resin containing the surface-treated silica filler, but no disclosure was made regarding adhesiveness after long-term storage. The inventors of the present invention conducted a study and found that when a similar treatment was performed on a radiopaque filler used to impart radiopacity, a property required for dental composite resins, dental cements, etc., there was room for further improvement in storage stability.

[0012] Therefore, an object of the present invention is to provide a dental composition that has excellent storage stability even under severe conditions and whose cured product has sufficient mechanical strength, a method for producing the same, and a dental surface-treated filler.

[0013] That is, the present invention includes the following: [1] A dental composition comprising a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), wherein the filler (C) comprises a surface-treated dental filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and wherein the amount of elution of metal components from the surface-treated dental filler (C-1) in an acid resistance test is less than 100 ppm. [2] The dental composition according to [1], wherein the end-capping agent (b) is a compound having a structure represented by the following formula (1) or (2) and having a boiling point of 180°C or lower: [In the formula, R １ ~R ６each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. x represents an integer of 3 to 10, and y represents an integer of 1 to 100.] [3] The dental composition according to [1] or [2], wherein the dental surface-treated filler (C-1) is surface-treated with the silane coupling agent (a) having a polymerizable group and then surface-treated with the end-capping agent (b). [4] The dental composition according to any one of [1] to [3], wherein the dental surface-treated filler (C-1) is surface-treated with the silane coupling agent (a) having a polymerizable group and then hydrolyzed. [5] The dental composition according to any one of [1] to [4], wherein the dental surface-treated filler (C-1) contains a radiopaque filler. [6] The dental composition according to [5], wherein the radiopaque filler is acid-treated. [7] The dental composition according to any one of [1] to [6], wherein the silane coupling agent (a) having a polymerizable group includes 3-methacryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, or a hydrolyzate thereof. [8] The dental composition according to any one of [1] to [7], wherein the end-capping agent (b) is hexamethylcyclotrisiloxane. [9] The dental composition according to any one of [1] to [8], wherein the amount of the end-capping agent (b) used in the surface treatment to obtain the dental surface-treated filler (C-1) is 0.01 to 20 parts by mass per 100 parts by mass of the filler before surface treatment.

[10] The dental composition according to any one of [1] to [9], wherein the polymerizable monomer (A) comprises a polymerizable monomer (A-1) having an acidic group and a polymerizable monomer (A-2) not having an acidic group.

[11] The dental composition according to

[10] , wherein the content of the polymerizable monomer (A-1) having an acidic group is 1 to 40 parts by mass per 100 parts by mass of the polymerizable monomer (A).

[12] A self-adhesive dental composite resin comprising the dental composition according to any one of [1] to

[11] .

[13] A dental bonding material comprising the dental composition according to any one of [1] to

[11] .

[14] A dental cement comprising the dental composition according to any one of [1] to

[11] .

[15] A dental composite resin comprising the dental composition according to any one of [1] to

[11] .

[16] A dental core material comprising the dental composition according to any one of [1] to

[11] .

[17] A method for producing the dental composition according to any one of [1] to

[11] , comprising a step of obtaining the dental surface-treated filler (C-1), the step comprising a step of surface-treating the filler with a silane coupling agent (a) having a polymerizable group, and a step of surface-treating the filler with an end-capping agent (b).

[18] A dental surface-treated filler (C-1), wherein the filler is surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and the end-capping agent (b) is a compound having a structure represented by the following formula (1) or (2) and having a boiling point of 180°C or lower: [In the formula, R １ ~R ６ each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. x represents an integer of 3 to 10, and y represents an integer of 1 to 100.]

[19] The dental surface-treated filler (C-1) according to

[18] , wherein the filler comprises an inorganic filler.

[20] The dental surface-treated filler (C-1) according to

[19] , wherein the inorganic filler comprises an aggregated filler.

[21] The dental surface-treated filler (C-1) according to any one of

[18] to

[20] , which has been surface-treated with the silane coupling agent (a) having a polymerizable group and then surface-treated with the end-capping agent (b).

[22] The dental surface-treated filler (C-1) according to any one of

[18] to

[21] , which has been surface-treated with the silane coupling agent (a) having a polymerizable group and then hydrolyzed.

[0014] According to the present invention, a dental composition that has excellent storage stability even under severe conditions and a cured product thereof that has sufficient mechanical strength, a method for producing the same, and a dental surface-treated filler can be provided. Furthermore, because the dental composition of the present invention has such excellent properties, it is suitable for use in self-adhesive dental composite resins, dental bonding materials, dental cements, dental composite resins, dental core construction materials, etc.

[0015] 1 shows the surface of a surface-treated filler used in a dental composition according to Comparative Example 1-1. 2 shows the surface of a surface-treated filler used in a dental composition according to Example 1-1.

[0016] The dental composition of the present invention comprises a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), wherein the filler (C) comprises a surface-treated filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and the amount of metal components eluted from the surface-treated filler (C-1) in an acid resistance test is less than 100 ppm. The end-capping agent (b) is preferably a compound having a specific structure described below and a boiling point of 180°C or lower.

[0017] In this specification, "(meth)acrylic" is a general term for methacrylic and acrylic, and the same applies to similar expressions (such as "(meth)acrylic acid" and "(meth)acrylonitrile"). In this specification, the upper and lower limits of numerical ranges (such as the content of each component, values ​​calculated from each component, and physical properties) can be combined as appropriate.

[0018] The reasons why the dental composition of the present invention has excellent storage stability even under harsh conditions (e.g., 60°C for 4 weeks, etc.) and the cured product thereof has sufficient mechanical strength are unclear, but are presumed to be as follows. First, by reacting the endcapping agent (b) having a specific structure and a boiling point of 180°C or less with the filler in the gas phase, the reaction rate can be increased compared to other surface treatment agents and reactions in the liquid phase. Furthermore, by using the endcapping agent (b) having a boiling point of 180°C or less, it is possible to carry out the reaction with the filler surface at a temperature at which the polymerizable group is not deactivated. As a result, it is presumed that the surface-treated filler (C-1) treated with the silane coupling agent (a) having a polymerizable group and the endcapping agent (b) having a specific structure and a boiling point of 180°C or less has a filler surface that is more densely covered with organic molecules than surface-treated fillers that have sufficient polymerizable groups on their surface to ensure mechanical strength and that have been surface-treated by conventional methods. Therefore, it is believed that good storage stability is maintained for a long period of time because interactions between the surface-treated filler (C-1) and other constituents are prevented.

[0019] Each component used in the dental composition of the present invention will be described below.

[0020] <Polymerizable Monomer (A)> A radically polymerizable monomer is preferably used as the polymerizable monomer (A) used in the dental composition of the present invention. Specific examples of the radically polymerizable monomer in the polymerizable monomer (A) include (meth)acrylate-based polymerizable monomers, (meth)acrylamide-based polymerizable monomers, esters of α-cyanoacrylic acid, (meth)acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, itaconic acid, and the like, vinyl esters, vinyl ethers, mono-N-vinyl derivatives, and styrene derivatives. Among these, (meth)acrylate-based polymerizable monomers and (meth)acrylamide-based polymerizable monomers are preferred from the viewpoint of curability. Furthermore, from the viewpoints of adhesion to tooth structure and elastic modulus, in the dental composition of the present invention, the polymerizable monomer (A) preferably contains a polymerizable monomer (A-1) having an acidic group and a polymerizable monomer (A-2) not having an acidic group.

[0021] Polymerizable Monomer (A-1) Having an Acidic Group In order to impart adhesiveness to tooth structure, a polymerizable monomer (A-1) having an acidic group is preferred. Examples of the polymerizable monomer (A-1) having an acidic group used in the present invention include polymerizable monomers having at least one acidic group such as a phosphate group, a pyrophosphate group, a thiophosphate group, a phosphonate group, a carboxylic acid group, or a sulfonic acid group. The polymerizable monomer (A-1) having an acidic group can be used alone or in appropriate combination of two or more types. Specific examples of the polymerizable monomer (A-1) having an acidic group are described below.

[0022] Examples of the polymerizable monomer having a phosphoric acid group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyhexyl dihydrogen phosphate, 9-(meth)acryloyloxyheptyl dihydrogen phosphate, 10-(meth)acryloyloxyhexyl dihydrogen phosphate, 11-(meth)acryloyloxyhexyl dihydrogen phosphate, 12-(meth)acryloyloxyhexyl dihydrogen phosphate, 13-(meth)acryloyloxyheptyl dihydrogen phosphate, 14-(meth)acryloyloxyhexyl dihydrogen phosphate, 15-(meth)acryloyloxyhexyl dihydrogen phosphate, 16-(meth)acryloyloxyhexyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxyhexyl dihydrogen phosphate, 19-(meth)acryloyloxyhexyl dihydrogen phosphate, 20-(meth)acryloyloxyhexyl dihydrogen phosphate, 21-(meth)acryloyloxyhexyl dihydrogen phosphate, 22-(meth)acryloyloxyhexyl dihydrogen phosphate, 23-(meth)acryloyloxyhexyl dihydrogen phosphate, 24-(meth)acryloyloxyhexyl dihydrogen phosphate, 25-(meth)acryloyloxyhexyl dihydrogen phosphate, 26-(meth)acryloyloxyhexyl dihydrogen phosphate, 27-( Acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate phosphate, bis[2-(meth)acryloyloxyethyl]hydrogenphosphate, bis[4-(meth)acryloyloxybutyl]hydrogenphosphate, bis[6-(meth)acryloyloxyhexyl]hydrogenphosphate, bis[8-(meth)acryloyloxyoctyl]hydrogenphosphate, bis[9-(meth)acryloyloxynonyl]hydrogenphosphate, bis[10-(meth)acryloyloxydecyl]hydrogenphosphate, 1,3-di Examples include (meth)acryloyloxypropyl-2-dihydrogen phosphate, 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogen phosphate, 2-methacryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, 2-methacryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0023] Examples of the polymerizable monomer having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl] pyrophosphate, bis[4-(meth)acryloyloxybutyl] pyrophosphate, bis[6-(meth)acryloyloxyhexyl] pyrophosphate, bis[8-(meth)acryloyloxyoctyl] pyrophosphate, bis[10-(meth)acryloyloxydecyl] pyrophosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0024] 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, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0025] Examples of the polymerizable monomer having a phosphonic acid group include 2-(meth)acryloyloxyethyl phenylphosphonate, 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonoacetate, 10-(meth)acryloyloxydecyl-3-phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0026] Examples of the polymerizable monomer having a carboxylic acid group include a monofunctional (meth)acrylic acid ester having one carboxyl group or an acid anhydride group thereof in the molecule, and a monofunctional (meth)acrylic acid ester having multiple carboxyl groups or acid anhydride groups thereof in the molecule.

[0027] Examples of monofunctional polymerizable monomers having one carboxyl group or an acid anhydride group thereof in the molecule include (meth)acrylic acid, N-(meth)acryloylglycine, N-(meth)acryloylaspartic acid, 2-(meth)acryloyloxyethyl hydrogen succinate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen maleate, O-(meth)acryloyltyrosine, N-(meth)acryloylthio Examples of the acryloyloxybenzoic acid include acryloylphenylalanine, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-o-aminobenzoic acid, 2-(meth)acryloyloxybenzoic acid, 3-(meth)acryloyloxybenzoic acid, 4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, and N-(meth)acryloyl-4-aminosalicylic acid, as well as compounds in which the carboxyl group of these compounds is converted to an acid anhydride group.

[0028] Examples of monofunctional polymerizable monomers having a plurality of carboxyl groups or acid anhydride groups thereof in the molecule include 6-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 9-(meth)acryloyloxynonane-1,1-dicarboxylic acid, 10-(meth)acryloyloxydecane-1,1-dicarboxylic acid, 11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid, 12-(meth)acryloyloxydodecane-1,1-dicarboxylic acid, 13-(meth)acryloyloxytridecane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyethyl trimellitate, 4-(meth)acryloyloxyethyl trimellitate anhydride ... butyl acryloyloxy trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethyl naphthalene-1,2,6-tricarboxylic acid anhydride, 6-(meth)acryloyloxyethyl naphthalene-2,3,6-tricarboxylic acid anhydride, 4-(meth)acryloyloxyethyl carbonylpropionoyl-1,8-naphthalic acid anhydride, 4-(meth)acryloyloxyethyl naphthalene-1,8-tricarboxylic acid anhydride, and the like.

[0029] Examples of the polymerizable monomer having a sulfonic acid group include 2-sulfoethyl (meth)acrylate.

[0030] Among the above-mentioned polymerizable monomers (A-1) having an acidic group, from the viewpoint of achieving good adhesive strength when used as a dental composition, it is preferable to include a polymerizable monomer having a phosphoric acid group or a polymerizable monomer having a carboxylic acid group, and examples thereof include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyethyl dihydrogen phosphate, 9-(meth)acryloyloxypropyl dihydrogen phosphate, 10-(meth)acryloyloxybutyl dihydrogen phosphate, 11-(meth)acryloyloxybutyl dihydrogen phosphate, 12-(meth)acryloyloxybutyl dihydrogen phosphate, 13-(meth)acryloyloxybutyl dihydrogen phosphate, 14-(meth)acryloyloxybutyl dihydrogen phosphate, 15-(meth)acryloyloxypentyl dihydrogen phosphate, 16-(meth)acryloyloxyhexyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxybutyl dihydrogen phosphate, 19-(meth)acryloyloxybutyl dihydrogen phosphate, 20-(meth)acryloyloxyethyl dihydrogen phosphate, 21-(meth)acryloyloxypropyl dihydrogen phosphate, 22-(meth)acryloyloxypropyl dihydrogen phosphate, 23-(meth)acryloyloxypropyl dihydrogen phosphate, 24-(meth)acryloyloxybutyl dihydrogen phosphate, 25-(meth)ac octyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 11-(meth)acryloyloxyundecane-1,1-Dicarboxylic acid and a mixture of 2-methacryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, and 20-(meth)acryloyloxyicosyl dihydrogen phosphate are even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being the most preferred from the viewpoint of a balance of curability.

[0031] From the viewpoint of adhesion to tooth structure, the content of the polymerizable monomer (A-1) having an acidic group in the dental composition of the present invention is preferably 1 to 40 parts by mass, more preferably 2.5 to 35 parts by mass, and even more preferably 5 to 30 parts by mass, per 100 parts by mass of the polymerizable monomer (A).

[0032] Polymerizable Monomer (A-2) Having No Acidic Group Examples of the polymerizable monomer (A-2) having no acidic group in the present invention include a hydrophobic polymerizable monomer (A-2a) having no acidic group and having a solubility of less than 10% by mass in water at 25° C., and a hydrophilic polymerizable monomer (A-2b) having no acidic group and having a solubility of 10% by mass or more in water at 25° C. One type of polymerizable monomer (A-2) having no acidic group may be used alone, or two or more types may be used in combination.

[0033] Hydrophobic Polymerizable Monomer (A-2a) Having No Acidic Group The hydrophobic polymerizable monomer (A-2a) having no acidic group (hereinafter sometimes simply referred to as "hydrophobic polymerizable monomer (A-2a)") improves the handleability of the dental composition and the mechanical strength of the cured product. As the hydrophobic polymerizable monomer (A-2a), a radical polymerizable monomer having no acidic group but a polymerizable group is preferred, and from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophobic polymerizable monomer (A-2a) refers to a polymerizable monomer having no acidic group and a solubility in water at 25°C of less than 10% by mass. Examples of the hydrophobic polymerizable monomer (A-2a) include, in addition to hydrophobic monofunctional polymerizable monomers, crosslinkable polymerizable monomers such as aromatic compound-based bifunctional polymerizable monomers, aliphatic compound-based bifunctional polymerizable monomers, and trifunctional or higher functional polymerizable monomers.

[0034] Examples of hydrophobic monofunctional polymerizable monomers include methyl methacrylate, ethyl methacrylate, butyl methacrylate, benzyl methacrylate, tetrahydrofurfuryl methacrylate, and isobornyl methacrylate, p-cumyl-phenoxyethylene glycol methacrylate (CMP-1E), 2-phenoxybenzyl methacrylate, stearyl methacrylate, dicyclopentanyl methacrylate, butoxydiethylene glycol methacrylate, methoxypolyethylene glycol methacrylate, and mixtures thereof. Of these, benzyl methacrylate, tetrahydrofurfuryl methacrylate, isobornyl methacrylate, CMP-1E, and mixtures thereof are preferred.

[0035] Examples of aromatic compound-based bifunctional polymerizable monomers include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(2-hydroxy-3-(meth)acryloyloxypropoxy)phenyl]propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane. 2-(4-(meth)acryloyloxydipropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, and the like. Among these, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6, commonly known as "D-2.6E"), 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane are preferred.

[0036] Examples of the aliphatic compound-based bifunctional polymerizable monomer include glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)di(meth)acrylate, N-methacryloyloxyethyl acrylamide, and N-methacryloyloxypropylamide. Among these, triethylene glycol diacrylate, triethylene glycol dimethacrylate (commonly known as "3G"), neopentyl glycol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate (commonly known as "UDMA"), 1,10-decanediol dimethacrylate (commonly known as "DD"), and N-methacryloyloxyethyl acrylamide (commonly known as "MAEA") are preferred.

[0037] Examples of trifunctional or higher functional polymerizable monomers include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetra(meth)acrylate, and 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane. Of these, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate is preferred.

[0038] Among the above hydrophobic polymerizable monomers (A-2a), aromatic bifunctional polymerizable monomers and aliphatic bifunctional polymerizable monomers are preferably used from the viewpoints of mechanical strength and handleability. Bis-GMA and D-2.6E are preferred as aromatic bifunctional polymerizable monomers. Glycerol di(meth)acrylate, 3G, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, DD, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, UDMA, and MAEA are preferred as aliphatic bifunctional polymerizable monomers.

[0039] Among the above-mentioned hydrophobic polymerizable monomers (A-2a), from the viewpoint of good adhesion to tooth structure when used in a dental composition, Bis-GMA, D-2.6E, 3G, UDMA, DD, and MAEA are more preferred, and Bis-GMA, D-2.6E, 3G, and MAEA are even more preferred.

[0040] The hydrophobic polymerizable monomer (A-2a) may be blended singly or in combination of two or more types. The content of the hydrophobic polymerizable monomer (A-2a) in the dental composition of the present invention is preferably 20 to 99 parts by mass, more preferably 40 to 95 parts by mass, and even more preferably 60 to 95 parts by mass, per 100 parts by mass of the polymerizable monomer (A). When the content of the hydrophobic polymerizable monomer (A-2a) is within the above range, the dental composition has excellent wettability to tooth structure, desired adhesion, and the cured product has desired mechanical strength.

[0041] Hydrophilic Polymerizable Monomer (A-2b) Having No Acidic Group: In the dental composition of the present invention, the polymerizable monomer (A) preferably contains a hydrophilic polymerizable monomer (A-2b) having no acidic group (hereinafter, sometimes simply referred to as "hydrophilic polymerizable monomer (A-2b)"). The hydrophilic polymerizable monomer (A-2b) improves the wettability of the dental composition to tooth structure. The hydrophilic polymerizable monomer (A-2b) is preferably a radically polymerizable monomer having no acidic group but a polymerizable group. From the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophilic polymerizable monomer (A-2b) refers to a monomer having no acidic group and a solubility in water at 25°C of 10% by mass or more, preferably a monomer having a solubility of 30% by mass or more, and more preferably a monomer that is soluble in water at any ratio at 25°C. The hydrophilic polymerizable monomer is preferably one having a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxypropylene group, an amide group, etc. Examples of the hydrophilic polymerizable monomer (A-2b) include hydrophilic monofunctional (meth)acrylate polymerizable monomers such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,3-dihydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 2-((meth)acryloyloxy)ethyltrimethylammonium chloride, and polyethylene glycol di(meth)acrylate (number of oxyethylene groups: 9 or more); Examples thereof include hydrophilic monofunctional (meth)acrylamide polymerizable monomers such as methylol(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N,N-bis(2-hydroxyethyl)(meth)acrylamide, N-methoxymethyl(meth)acrylamide, N-ethoxymethyl(meth)acrylamide, diacetone(meth)acrylamide, 4-(meth)acryloylmorpholine, N-trihydroxymethyl-N-methyl(meth)acrylamide, N,N-dimethylacrylamide, and N,N-diethylacrylamide.

[0042] Among these hydrophilic polymerizable monomers (A-2b), from the viewpoint of adhesion to tooth structure, 2-hydroxyethyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and hydrophilic monofunctional (meth)acrylamide polymerizable monomers are preferred, and 2-hydroxyethyl (meth)acrylate, N,N-dimethylacrylamide, and N,N-diethylacrylamide are more preferred. One type of hydrophilic polymerizable monomer (A-2b) may be blended alone, or two or more types may be blended in combination.

[0043] The content of the hydrophilic polymerizable monomer (A-2b) in the dental composition of the present invention is preferably in the range of 0 to 50 parts by mass, more preferably 0 to 40 parts by mass, and even more preferably 0 to 30 parts by mass, per 100 parts by mass of the polymerizable monomer (A). The content of the hydrophilic polymerizable monomer (A-2b) may be 0 parts by mass per 100 parts by mass of the polymerizable monomer (A). When the content of the hydrophilic polymerizable monomer (A-2b) is within the above range, an improved effect on adhesion is obtained, and the cured product has the desired mechanical strength.

[0044] The content of the polymerizable monomer (A-2) having no acidic group is preferably 50 to 99 parts by mass, more preferably 60 to 97 parts by mass, and even more preferably 70 to 95 parts by mass, per 100 parts by mass of the polymerizable monomer (A).

[0045] <Polymerization initiator (B)> The polymerization initiator (B) is classified into a water-soluble photopolymerization initiator (B-1), a water-insoluble photopolymerization initiator (B-2), and a chemical polymerization initiator (B-3). As the polymerization initiator (B), only the water-soluble photopolymerization initiator (B-1) may be used, only the water-insoluble photopolymerization initiator (B-2) may be used, or only the chemical polymerization initiator (B-3) may be used, or the water-soluble photopolymerization initiator (B-1), the water-insoluble photopolymerization initiator (B-2), and the chemical polymerization initiator (B-3) may be used in combination.

[0046] Water-soluble photopolymerization initiator (B-1) improves polymerization curing at the hydrophilic tooth surface interface, enabling high adhesive strength to be achieved. The water-soluble photopolymerization initiator (B-1) has a solubility in water at 25°C of 10 g / L or more, preferably 15 g / L or more, more preferably 20 g / L or more, and even more preferably 25 g / L or more. A solubility of 10 g / L or more allows the water-soluble photopolymerization initiator (B-1) to dissolve sufficiently in the water in the tooth substance at the adhesive interface, making it easier to achieve a polymerization-promoting effect.

[0047] Examples of the water-soluble photopolymerization initiator (B-1) include water-soluble acylphosphine oxides; water-soluble thioxanthones; 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one in which a (poly)ethylene glycol chain is introduced to the hydroxyl group, 1-hydroxycyclohexyl phenyl ketone in which a (poly)ethylene glycol chain is introduced to the hydroxyl group and / or phenyl group, and 1-hydroxycyclohexyl phenyl ketone in which a -OCH ２ COO － Na ＋ a compound in which a (poly)ethylene glycol chain is introduced into the hydroxyl group and / or phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one; a compound in which —OCH ２ COO － Na ＋ and α-aminoalkylphenones in which the amino group of an α-aminoalkylphenone such as 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one or 2-benzyl-2-(dimethylamino)-1-[(4-morpholino)phenyl]-1-butanone has been converted into a quaternary ammonium salt.

[0048] Examples of the water-soluble thioxanthones include 2-hydroxy-3-(9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1-methyl-9-oxo-9H-thioxanthen-4-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2- Hydroxy-3-(3,4-dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(3,4-dimethyl-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, 2-hydroxy-3-(1,3,4-trimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1-propanaminium chloride, and the like can be used.

[0049] Examples of the water-soluble acylphosphine oxides include acylphosphine oxides represented by the following general formula (4) or (5).

[0050]

[0051]

[0052] In the formula, A １ , A ２ , A ３ , A ４ , A ５ , and A ６ are independent of each other, C １ ~C ４ and M is a hydrogen ion, an alkali metal ion, an alkaline earth metal ion, a magnesium ion, a pyridinium ion (the pyridine ring may have a substituent), or HN ＋ A ８ A ９ A １０ (In the formula, A ８ , A ９ , and A １０are each independently an organic group or a hydrogen atom), n is 1 or 2, and Z is C １ ~C ４ A is a linear or branched alkylene group represented by the formula: ７ Ha -CH (CH ３ ) COO (C ２ H ４ O) ｐ CH ３ where p is an integer of 1 to 1000.

[0053] A １ , A ２ , A ３ , A ４ , A ５ , and A ６ The alkyl group of １ ~C ４ There are no particular limitations on the alkyl group as long as it is a straight-chain or branched-chain alkyl group, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a 2-methylpropyl group, and a tert-butyl group. １ , A ２ , A ３ , A ４ , A ５ , and A ６ The alkyl group of １ ~C ３ The alkylene group represented by Z is preferably a linear alkyl group represented by the formula (I), more preferably a methyl group or an ethyl group, and even more preferably a methyl group. Examples of the alkylene group represented by Z include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, and an n-butylene group. Examples of the alkylene group represented by Z include a C １ ~C ３ A straight-chain alkylene group such as those shown above is preferred, a methylene group or an ethylene group is more preferred, and a methylene group is even more preferred.

[0054] When M is a pyridinium ion, the substituent on the pyridine ring may be a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a carboxyl group, ２ ~C ６ a linear or branched acyl group of １ ~C ６ a linear or branched alkyl group of C１ ~C ６ Examples of M include an alkali metal ion, an alkaline earth metal ion, a magnesium ion, a pyridinium ion (the pyridine ring may have a substituent), or HN ＋ A ８ A ９ A １０ (wherein the symbols have the same meanings as above) is preferred. Examples of alkali metal ions include lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion. Examples of alkaline earth metal ions include calcium ion, strontium ion, barium ion, and radium ion. A ８ , A ９ , and A １０ Examples of the organic group include the same groups as the substituents on the pyridine ring (excluding halogen atoms).

[0055] Among these, A １ , A ２ , A ３ , A ４ , A ５ , and A ６ A compound in which all of M are methyl groups is particularly preferred from the viewpoint of storage stability and color stability in the composition. ｎ＋ Examples of ＋ , Na ＋ , K. ＋ , Ca ２＋ , Mg ２＋ and ammonium ions derived from various amines, and examples of amines include ammonia, trimethylamine, diethylamine, dimethylaniline, ethylenediamine, triethanolamine, N,N-dimethylamino methacrylate, 4-(N,N-dimethylamino)benzoic acid and its alkyl esters, 4-(N,N-diethylamino)benzoic acid and its alkyl esters, and N,N-bis(2-hydroxyethyl)-p-toluidine. ７In the formula, from the viewpoint of adhesiveness, p is 1 or more, preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more; and is 1,000 or less, preferably 100 or less, more preferably 75 or less, and even more preferably 50 or less.

[0056] Among these water-soluble acylphosphine oxides, M ｎ＋ Li ＋ A compound represented by general formula (4) ７ In these compounds, a compound synthesized from polyethylene glycol methyl ether methacrylate in which the part corresponding to the group represented by the formula (4) has a molecular weight of 950 is particularly preferred. １ , A ２ , and A ３ and A in general formula (5) １ , A ２ , A ３ , A ４ , A ５ , and A ６ is as described above.

[0057] Water-soluble acylphosphine oxides having such a structure can be synthesized according to known methods, and some are also commercially available. For example, they can be synthesized by the methods disclosed in JP-A-57-197289 and WO 2014 / 095724. The water-soluble photopolymerization initiator (B-1) may be used alone or in combination of two or more.

[0058] The water-soluble photopolymerization initiator (B-1) may be dissolved in the dental composition or dispersed in the composition in the form of a powder.

[0059] When the water-soluble photopolymerization initiator (B-1) is dispersed in the composition in the form of a powder, if the average particle size is too large, it tends to settle, so it is preferably 500 μm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. On the other hand, if the average particle size is too small, the specific surface area of ​​the powder becomes too large, reducing the amount dispersible in the composition, so it is preferably 0.01 μm or more. That is, the average particle size of the water-soluble photopolymerization initiator (B-1) is preferably in the range of 0.01 to 500 μm, more preferably 0.01 to 100 μm, and even more preferably 0.01 to 50 μm.

[0060] The average particle size of the powder of each water-soluble photopolymerization initiator (B-1) can be calculated as a volume average particle size after performing image analysis using image analysis particle size distribution measurement software (Mac-View; manufactured by Mountech Co., Ltd.) based on an electron microscope photograph of 100 or more particles.

[0061] When the water-soluble photopolymerization initiator (B-1) is dispersed in the composition in the form of a powder, the shape of the initiator is not particularly limited, and various shapes such as spherical, needle-like, plate-like, crushed, etc. can be mentioned. The water-soluble photopolymerization initiator (B-1) can be prepared by a conventionally known method such as a pulverization method, a freeze-drying method, or a reprecipitation method. From the viewpoint of the average particle size of the obtained powder, the freeze-drying method and the reprecipitation method are preferred, and the freeze-drying method is more preferred.

[0062] The content of the water-soluble photopolymerization initiator (B-1) is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the polymerizable monomer (A) in the dental composition of the present invention from the viewpoint of the curability of the resulting dental composition, and more preferably 0.05 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, from the viewpoint of adhesion to tooth structure. When the content of the water-soluble photopolymerization initiator (B-1) is 0.01 part by mass or more, polymerization at the adhesive interface proceeds sufficiently, and the desired adhesiveness is obtained. On the other hand, when the content of the water-soluble photopolymerization initiator (B-1) is 20 parts by mass or less, sufficient adhesiveness is obtained.

[0063] Water-insoluble photopolymerization initiator (B-2) From the viewpoint of curability, the dental composition of the present invention preferably contains, in addition to the water-soluble photopolymerization initiator (B-1), a water-insoluble photopolymerization initiator (B-2) having a solubility in water at 25°C of less than 10 g / L (hereinafter, may be referred to as water-insoluble photopolymerization initiator (B-2)). The water-insoluble photopolymerization initiator (B-2) used in the present invention can be a known photopolymerization initiator. The water-insoluble photopolymerization initiator (B-2) may be used alone or in combination of two or more.

[0064] Examples of the water-insoluble photopolymerization initiator (B-2) include (bis)acylphosphine oxides, thioxanthones, ketals, α-diketones, coumarins, anthraquinones, benzoin alkyl ether compounds, and α-aminoketone compounds other than the water-soluble photopolymerization initiator (B-1).

[0065] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, and benzoyldi(2,6-dimethylphenyl)phosphonate. Examples of bisacylphosphine oxides include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide.

[0066] Examples of the thioxanthones include thioxanthone and 2-chlorothioxanthen-9-one.

[0067] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0068] Examples of the α-diketones include diacetyl, benzil, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzil, acenaphthenequinone, etc. Among these, dl-camphorquinone is particularly preferred from the viewpoint of having a maximum absorption wavelength in the visible light region.

[0069] Examples of the coumarins include 3,3'-carbonylbis(7-diethylaminocoumarin), 3-(4-methoxybenzoyl)coumarin, 3-thienoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin, 3-benzoylcoumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin), 3-benzoyl-6-bromo Coumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin, 3-carboxycoumarin, 3-carboxy-7-methoxycoumarin, 3-ethoxycarbonyl-6-methoxycoumarin, 3-ethoxycarbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin, 3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-methoxybenzoyl) ) coumarin, 7-diethylamino-3-(4-diethylamino)coumarin, 7-methoxy-3-(4-methoxybenzoyl)coumarin, 3-(4-nitrobenzoyl)benzo[f]coumarin, 3-(4-ethoxycinnamoyl)-7-methoxycoumarin, 3-(4-dimethylaminocinnamoyl)coumarin, 3-(4-diphenylaminocinnamoyl)coumarin, 3-[(3-dimethylbenzothiazol-2-ylidene)acetyl]coumarin, 3-[(1-methylnaphtho[1,2-d]thiazol-2-ylidene)acetyl]coumarin, 3,3'-carbo Nylbis(6-methoxycoumarin), 3,3'-carbonylbis(7-acetoxycoumarin), 3,3'-carbonylbis(7-dimethylaminocoumarin), 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dibutylamino)coumarin, 3-(2-benzimidazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dioctylamino)coumarin, 3-acetyl-7-(dimethylamino)coumarin, 3,3'-carbonylbis(7-dibutylaminocoumarin), 3,Examples of compounds include those described in JP-A-9-3109 and JP-A-10-245525, such as 3'-carbonyl-7-diethylaminocoumarin-7'-bis(butoxyethyl)aminocoumarin, 10-[3-[4-(dimethylamino)phenyl]-1-oxo-2-propenyl]-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one, and 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one.

[0070] Among the above-mentioned coumarins, 3,3'-carbonylbis(7-diethylaminocoumarin) and 3,3'-carbonylbis(7-dibutylaminocoumarin) are particularly preferred.

[0071] Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benzanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-hydroxyanthraquinone.

[0072] Examples of the benzoin alkyl ether compounds include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

[0073] Examples of the α-aminoketone compounds include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.

[0074] Among these water-insoluble photopolymerization initiators (B-2), it is preferable to use at least one selected from the group consisting of (bis)acylphosphine oxides, α-diketones, and coumarins, which allows for the production of a dental composition that has excellent photocurability in the visible and near-ultraviolet regions and exhibits sufficient photocurability using any of a halogen lamp, a light-emitting diode (LED), and a xenon lamp as a light source.

[0075] The content of the water-insoluble photopolymerization initiator (B-2) is not particularly limited, but from the viewpoint of the curability of the resulting dental composition, it is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the polymerizable monomer (A) in the dental composition of the present invention. Note that, when the content of the water-insoluble photopolymerization initiator (B-2) is 10 parts by mass or less, sufficient adhesiveness can be obtained.

[0076] When the water-soluble photopolymerization initiator (B-1) and the water-insoluble photopolymerization initiator (B-2) are used in combination, the mass ratio of the water-soluble photopolymerization initiator (B-1) to the water-insoluble photopolymerization initiator (B-2) [(B-1):(B-2)] in the present invention is preferably 10:1 to 1:10, more preferably 7:1 to 1:7, even more preferably 5:1 to 1:5, and most preferably 3:1 to 1:3. If the water-soluble photopolymerization initiator (B-1) is contained in a mass ratio of more than 10:1, the curability of the dental composition itself may be reduced, making it difficult to achieve high adhesive strength. On the other hand, if the water-insoluble photopolymerization initiator (B-2) is contained in a mass ratio of more than 1:10, although the curability of the dental composition itself is enhanced, the promotion of polymerization at the adhesive interface may be insufficient, making it difficult to achieve high adhesive strength.

[0077] Chemical Polymerization Initiator (B-3) The dental composition of the present invention can contain a chemical polymerization initiator (B-3), and an organic peroxide is preferably used. The organic peroxide used as the chemical polymerization initiator is not particularly limited, and known organic peroxides can be used. Representative organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, and peroxydicarbonates. Specific examples of these organic peroxides include those described in WO 2008 / 087977. The chemical polymerization initiator (B-3) may be used alone or in combination of two or more.

[0078] <Filler (C)> The dental composition of the present invention contains a filler (C) to adjust handleability and to increase the mechanical strength of the cured product. Examples of the filler (C) include the dental surface-treated filler (C-1) described below; and fillers other than the dental surface-treated filler (C-1), such as inorganic fillers, organic fillers, and organic-inorganic composite fillers. The filler (C) may be blended singly or in combination of two or more. An example of a dental composition includes a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), wherein the filler (C) includes a dental surface-treated filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and a filler other than the dental surface-treated filler (C-1), and the dental surface-treated filler (C-1) exhibits an elution amount of metal components of less than 100 ppm in an acid resistance test. First, fillers other than the dental surface-treated filler (C-1) will be described.

[0079] Examples of organic filler materials include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, cross-linked polymethyl methacrylate, cross-linked polyethyl methacrylate, polyamide, polyvinyl chloride, polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, and acrylonitrile-styrene-butadiene copolymer. These may be used alone or in combination of two or more. The shape of the organic filler is not particularly limited, and the particle size of the filler can be appropriately selected. From the viewpoints of the handleability and mechanical strength of the resulting dental composition, the average particle size of the organic filler is preferably 0.001 to 50 μm, and more preferably 0.001 to 10 μm.

[0080] The inorganic filler material may be various glasses (mainly composed of silica, and optionally containing oxides of heavy metals, boron, aluminum, etc.). For example, glass powders of general compositions such as fused silica, quartz, soda lime silica glass, E glass, C glass, and borosilicate glass (Pyrex (registered trademark) glass); dental glass powders such as barium glass (GM27884, 8235, manufactured by SCHOTT, E-2000, E-3000, manufactured by ESSTECH), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by SCHOTT), and fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by SCHOTT), various ceramics, composite oxides such as silica-titania and silica-zirconia, silica-zirconia oxide agglomerated fillers, diatomaceous earth, kaolin, and clay minerals (montmorillonite, etc.). , activated clay, synthetic zeolite, mica, calcium fluoride, ytterbium fluoride, yttrium fluoride, calcium fluoride having a core-shell structure whose surface is coated with silica, ytterbium fluoride having a core-shell structure whose surface is coated with silica, yttrium fluoride having a core-shell structure whose surface is coated with silica, calcium phosphate, barium sulfate, zirconium dioxide, titanium dioxide, hydroxyapatite, calcium phosphate having a core-shell structure whose surface is coated with silica, barium sulfate having a core-shell structure whose surface is coated with silica, zirconium dioxide having a core-shell structure whose surface is coated with silica, titanium dioxide having a core-shell structure whose surface is coated with silica, and hydroxyapatite having a core-shell structure whose surface is coated with silica.Among these, from the viewpoint of strength, etc., various glasses, composite oxides such as silica-titania and silica-zirconia, silica-zirconia oxide agglomerated fillers, calcium fluoride having a core-shell structure coated with silica, ytterbium fluoride having a core-shell structure coated with silica, yttrium fluoride having a core-shell structure coated with silica, calcium phosphate having a core-shell structure coated with silica, barium sulfate having a core-shell structure coated with silica, zirconium dioxide having a core-shell structure coated with silica, titanium dioxide having a core-shell structure coated with silica, and hydroxyapatite having a core-shell structure coated with silica are preferred. These may be used alone or in combination of two or more. In the present invention, when the filler is surface-treated, the average particle size of the filler means the average particle size before the surface treatment.

[0081] Examples of the shape of the inorganic filler include amorphous fillers and spherical fillers. From the viewpoint of improving the mechanical strength of the cured dental composition, it is preferable to use a spherical filler as the inorganic filler. The spherical filler used in the present invention is a filler in which, when photographed with an electron microscope, the particles observed within a unit field of view are rounded and have an average uniformity of 0.6 or more, calculated by dividing the particle diameter in a direction perpendicular to the maximum diameter by the maximum diameter. The average particle diameter of the filler is preferably 0.05 to 50 μm, more preferably 0.1 to 30 μm, and even more preferably 0.5 μm to 30 μm. If the average particle diameter is less than 0.05 μm, the filling rate of the filler in the dental composition may decrease, resulting in reduced mechanical strength. On the other hand, if the average particle diameter exceeds 50 μm, the surface area of ​​the filler may decrease, preventing the formation of a cured dental composition with high mechanical strength.

[0082] In some embodiments, it is preferable to include an agglomerated filler as the inorganic filler. Agglomerated fillers are fillers that form secondary particles formed by agglomeration of primary particles, and are characterized by exhibiting high mechanical strength and excellent polishability (the property of easily achieving a desired smoothness with short polishing times). A single type of agglomerated filler may be used, or two or more types may be used in combination. The agglomerated filler is preferably an agglomerated metal oxide primary particle. The metal oxide may be a composite oxide. Examples of composite oxides include silica-zirconia and silica-titania. From the viewpoint of the polishability of the resulting dental composition, silica-zirconia oxide is preferred as the metal oxide. From the viewpoint of the handleability and mechanical strength of the resulting dental composition, the average particle size of the secondary particles of the agglomerated filler is 1 to 20 μm, preferably 1.5 to 15 μm, more preferably 2 to 12.5 μm, and even more preferably 3 to 10 μm. Furthermore, from the viewpoint of ease of polishing the resulting dental composition, the average particle size of the primary particles of the agglomerated filler is preferably 30 to 500 nm, more preferably 40 to 400 nm, even more preferably 50 to 300 nm, and particularly preferably 60 to 200 nm. Commercially available agglomerated fillers may be used. Examples of commercially available products include silica-zirconia oxide agglomerated fillers "SG-SZ200G151CMP8," "SG-SZ50G151CMP8," and "SG-SZ200G154CMP8" (manufactured by Sukgyung AT).

[0083] The organic-inorganic composite filler that may be used in the present invention is obtained by adding a polymerizable monomer to the inorganic filler described above in advance, forming a paste, polymerizing it, and pulverizing it. Examples of the organic-inorganic composite filler that can be used include TMPT filler (trimethylolpropane methacrylate and silica filler mixed, polymerized, and then pulverized). The shape of the organic-inorganic composite filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoints of the handleability and mechanical strength of the resulting composition, the average particle size of the organic-inorganic composite filler is preferably 0.001 to 50 μm, and more preferably 0.001 to 10 μm.

[0084] In this specification, the average particle size of the filler can be determined by a laser diffraction scattering method or by observing the particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, and electron microscope observation is convenient for measuring the particle size of ultrafine particles less than 0.1 μm. The value of 0.1 μm is a value measured by the laser diffraction scattering method.

[0085] Specifically, the laser diffraction scattering method can be performed by using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation) on a volume basis using a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium.

[0086] Specifically, electron microscope observation can be performed by taking a photograph of the particles using an electron microscope (S-4000 model, manufactured by Hitachi, Ltd.) and measuring the particle diameters of particles (200 or more) observed within a unit field of view of the photograph using image analysis particle size distribution measurement software (Mac-View (manufactured by Mountec Co., Ltd.)). In this case, the particle diameter 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.

[0087] The dental composition of the present invention preferably uses a mixture or combination of two or more fillers with different materials, particle size distributions, and morphologies. Combining two or more fillers allows the fillers to be densely packed and increases the number of interaction points between the filler and the polymerizable monomer, or between the fillers themselves. Furthermore, the type of filler can control the fluidity of the paste depending on whether or not shear force is applied. Fillers of each particle size may contain different types of fillers. Furthermore, particles other than fillers may be unintentionally contained as impurities within a range that does not impair the effects of the present invention.

[0088] In order to adjust the fluidity of the dental composition, the filler may be surface-treated in advance with a known surface treatment agent such as a silane coupling agent, if necessary. Examples of such surface treatment agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, 3-methacryloyloxypropyltrimethoxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, and 3-aminopropyltriethoxysilane.

[0089] Dental surface-treated filler (C-1) surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b). The dental composition of the present invention contains, as filler (C), a silane coupling agent (a) having a polymerizable group (hereinafter sometimes simply referred to as "silane coupling agent (a)") and a dental surface-treated filler (C-1) surface-treated with an end-capping agent (b) (hereinafter sometimes simply referred to as "dental surface-treated filler (C-1)"). By including the dental surface-treated filler (C-1) in the dental composition, a dental composition can be obtained that has excellent storage stability even under harsh conditions (e.g., 60°C for 4 weeks, etc.), and the cured product thereof has sufficient mechanical strength. The amount of metal components eluted from the dental surface-treated filler (C-1) in an acid resistance test is less than 100 ppm. The amount of elution of the metal components is preferably 95 ppm or less, more preferably 90 ppm or less, even more preferably 70 ppm or less, and particularly preferably 50 ppm or less. The method for measuring the amount of elution of metal components in the acid resistance test is as described in the Examples below. The dental surface-treated filler (C-1) preferably has a structure derived from the silane coupling agent (a) and a structure derived from the end-capping agent (b) on the surface of the filler. Furthermore, the dental surface-treated filler (C-1) preferably has a structure derived from the silane coupling agent (a) chemically bonded to the surface of the filler. Furthermore, the dental surface-treated filler (C-1) preferably has a structure derived from the end-capping agent (b) chemically bonded to the surface of the filler. Furthermore, the dental surface-treated filler (C-1) preferably has a structure derived from the silane coupling agent (a) and a structure derived from the end-capping agent (b) chemically bonded to the surface of the filler. Furthermore, the dental surface-treated filler (C-1) preferably has a structure in which the structure derived from the silane coupling agent (a) and the structure derived from the end-capping agent (b) are chemically bonded to each other.

[0090] Silane coupling agent (a) having a polymerizable group The surface-treated dental filler (C-1) is also surface-treated with a silane coupling agent (a) having a polymerizable group. There are no particular limitations on the silane coupling agent (a), and any known silane coupling agent can be used, but a silane coupling agent represented by the general formula (6) is preferably used. Y-SiR ｐX （３－ｐ） (6) (In the formula, Y represents a polymerizable group or a monovalent organic group having a polymerizable group, R represents a group selected from the group consisting of an alkyl group, an aryl group, and an aralkyl group, X represents a hydroxyl group or a hydrolyzable group, and p represents an integer of 0, 1, or 2. However, multiple Rs may be the same or different, and multiple Xs may be the same or different.)

[0091] The type of polymerizable group that Y has is not particularly limited, and examples thereof include a (meth)acryloyl group, a vinyl group, a mercapto group, a (meth)allyl group, and an epoxy group. Among these, from the viewpoint of mechanical strength, etc., a (meth)acryloyl group is preferred, and a methacryloyl group is more preferred. The polymerizable group may be directly bonded to a monovalent organic group, or may be bonded to a monovalent organic group via a divalent group containing a heteroatom such as an oxygen atom or a nitrogen atom. For example, the (meth)acryloyl group may form a (meth)acryloyloxy group or a (meth)acrylamide group.

[0092] The number of polymerizable groups that Y has is not particularly limited, but is preferably 1 to 4, more preferably 1 or 2, and even more preferably 1. When Y has a plurality of polymerizable groups, they may be the same or different from one another.

[0093] Y may be formed solely from the polymerizable group, or may be a bond between the functional group and an organic group, either directly or indirectly via a divalent group containing a heteroatom such as an oxygen atom or a nitrogen atom. The organic group is not particularly limited, and examples thereof include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 18 carbon atoms, and an aralkyl group having 7 to 26 carbon atoms. Among these, an alkyl group having 1 to 20 carbon atoms is preferred, an alkyl group having 1 to 12 carbon atoms is more preferred, and an alkyl group having 3 to 11 carbon atoms is even more preferred, as they provide improved adhesion to both dental restorative materials and tooth structure. Examples of alkyl groups having 3 to 11 carbon atoms include an n-propyl group, an isopropyl group, an n-butyl group, an n-pentyl group, an n-octyl group, and an n-undecyl group. An n-propyl group, an n-pentyl group, an n-octyl group, and an n-undecyl group are preferred, with an n-propyl group, an n-octyl group, and an n-undecyl group being more preferred.

[0094] Specific examples of Y include a (meth)acryloyloxymethyl group, a 3-(meth)acryloyloxypropyl group, a 3-(meth)acrylamidopropyl group, a vinyl group, a (meth)allyl group, and a 3-glycidoxypropyl group. Of these, a (meth)acryloyloxymethyl group, a 3-(meth)acryloyloxypropyl group, a 3-(meth)acryloyloxyoctyl group, and a 3-(meth)acryloyloxyundecyl group are preferred, and a 3-(meth)acryloyloxypropyl group, an 8-(meth)acryloyloxyoctyl group, and an 11-(meth)acryloyloxyundecyl group are more preferred.

[0095] The type of alkyl group represented by R is not particularly limited, and examples thereof include alkyl groups having 1 to 5 carbon atoms, more specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and an n-pentyl group.

[0096] There is no particular limitation on the type of aryl group represented by R, and examples thereof include aryl groups having 6 to 10 carbon atoms, more specifically, examples thereof include phenyl groups and naphthyl groups.

[0097] The type of aralkyl group represented by R is not particularly limited, and examples thereof include aralkyl groups having 7 to 12 carbon atoms, and more specifically, examples thereof include benzyl groups.

[0098] Among these, from the viewpoint of mechanical strength and the like, R is preferably an alkyl group, more preferably an alkyl group having 1 to 5 carbon atoms, and even more preferably a methyl group.

[0099] The hydrolyzable group represented by X can be a group that can form a silanol group together with the silicon atom to which it is bonded by hydrolysis, and examples thereof include an alkoxy group, an acyloxy group, a siloxy group, and a halogen atom.

[0100] The type of the alkoxy group is not particularly limited, and examples thereof include alkoxy groups having 1 to 5 carbon atoms, more specific examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, and an n-pentyloxy group.

[0101] The type of the acyloxy group is not particularly limited, and examples thereof include acyloxy groups having 1 to 5 carbon atoms, and more specific examples thereof include a formyloxy group, an acetoxy group, an n-propionyloxy group, an isopropionyloxy group, an n-butanoyloxy group, and an n-pentanoyloxy group.

[0102] There are no particular limitations on the type of the siloxy group, and examples thereof include a trimethylsiloxy group.

[0103] The type of the halogen atom is not particularly limited, and examples thereof include a chlorine atom and a bromine atom.

[0104] Among these, X is preferably an alkoxy group, more preferably an alkoxy group having 1 to 5 carbon atoms, and even more preferably a methoxy group or an ethoxy group.

[0105] p represents an integer of 0, 1, or 2, and from the viewpoint of the mechanical strength of the cured product, p is preferably 0 or 1. When p is 0 or 1, multiple Xs may be the same or different from each other, and when p is 2, multiple Rs may be the same or different from each other.

[0106] Specific examples of the silane coupling agent (a) include (meth)acryloyloxymethyltrimethoxysilane, 2-(meth)acryloyloxyethyltrimethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 4-(meth)acryloyloxybutyltrimethoxysilane, 5-(meth)acryloyloxypentyltrimethoxysilane, 6-(meth)acryloyloxyhexyltrimethoxysilane, 7-(meth)acryloyloxyheptyltrimethoxysilane, and 8-(meth)acryloyloxyoctyltrimethoxysilane. Silane, 9-(meth)acryloyloxynonyltrimethoxysilane, 10-(meth)acryloyloxydecyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, 11-(meth)acryloyloxyundecyldichloromethylsilane, 11-(meth)acryloyloxyundecyltrichlorosilane, 11-(meth)acryloyloxyundecyldimethoxymethylsilane, 12-(meth)acryloyloxydodecyltrimethoxysilane, 13-(meth)acryloyloxytridecyltrimethoxysilane, 3- (meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, 3-(meth)acryloyloxypropylmethyldiisopropoxysilane, 3-(meth)acryloyloxypropylmethyldimethylsiloxysilane, 3-(meth)acryloyloxypropylmethyldihexyloxysilane, (meth)acryloyloxy-2-(2-vinyloxyethoxy)ethylmethyldimethoxysilane, 6-(meth)acryloyloxyhexylmethyldimethoxysilane, (meth)acryloyloxy -p-phenylethylmethyldimethoxysilane, 6-(meth)acryloyloxyhexylmethyldiethoxysilane, 10-(meth)acryloyloxydecylmethyldimethoxysilane, 11-(meth)acryloyloxyundecylmethyldimethoxysilane, 11-(meth)acryloyloxyundecylmethyldiethoxysilane, 11-(meth)acryloyloxyundecylmethyldihexyloxysilane, 20-(meth)acryloyloxyeicosylmethyldimethoxysilane, 3-(meth)acryloyloxypropylphenyldimethoxysilane,3-(meth)acryloyloxypropylmethyldichlorosilane, 11-(meth)acryloyloxyundecylmethyldichlorosilane, 11-(meth)acryloyloxyundecylethyldichlorosilane, 3-(meth)acryloyloxypropyldimethylmonomethoxysilane, 3-(meth)acryloyloxypropyldimethylmonoethoxysilane, 3-(meth)acryloyloxypropyldimethylmonoisopropoxysilane, 3-(meth)acryloyloxypropyldimethylmonotrimethylsiloxysilane, 3-(meth)acryloyloxypropyldimethylmonotrimethylsiloxysilane Dipropyldimethylmonohexyloxysilane, (meth)acryloyloxy-2-(2-vinyloxyethoxy)ethyldimethylmonomethoxysilane, 6-(meth)acryloyloxyhexyldimethylmonomethoxysilane, (meth)acryloyloxy-p-phenylethyldimethylmonomethoxysilane, 6-(meth)acryloyloxyhexyldimethylmonoethoxysilane, 10-(meth)acryloyloxydecyldimethylmonomethoxysilane, 11-(meth)acryloyloxyundecyldimethylmonomethoxysilane, 11-(meth)acryloyloxydecyldimethylmonomethoxysilane, (meth)acryloyl group-containing silanes such as 11-(meth)acryloyloxyundecyldimethylmonoethoxysilane, 11-(meth)acryloyloxyundecyldimethylmonohexyloxysilane, 20-(meth)acryloyloxyeicosyldimethylmonomethoxysilane, 3-(meth)acryloyloxypropyldiphenylmonomethoxysilane, 3-(meth)acryloyloxypropyldimethylmonochlorosilane, 11-(meth)acryloyloxyundecyldimethylmonochlorosilane, and 11-(meth)acryloyloxyundecyldiethylmonochlorosilane. coupling agents: vinyl group-containing silane coupling agents such as vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldichlorosilane, vinylmethyldiacetoxysilane, vinylmethyldi(2-methoxyethoxy)silane, vinyldimethylmonomethoxysilane, vinyldimethylmonoethoxysilane, vinyldimethylmonochlorosilane, vinyldimethylmonoacetoxysilane, and vinyldimethylmono(2-methoxyethoxy)silane; 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane,Examples of suitable silane coupling agents include epoxy group-containing silane coupling agents such as 3-glycidoxypropyldimethylmonomethoxysilane and 3-glycidoxypropyldimethylmonoethoxysilane; and allyl group-containing silane coupling agents such as allylmethyldiethoxysilane and allyldimethylmonoethoxysilane. The silane coupling agent (a) may also be a hydrolyzed and / or condensed version of these. The silane coupling agent (a) may be used alone or in combination of two or more. Among these, from the viewpoint of mechanical strength and the like, 3-methacryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, and hydrolyzates thereof are preferred.

[0107] End-capping agent (b) The surface-treated dental filler (C-1) is surface-treated with an end-capping agent (b) in addition to the silane coupling agent (a). The end-capping agent (b) is preferably a compound having a structure represented by the following general formula (1) or (2) and having a boiling point of 180°C or lower: [In the formula, R １ ~R ６ each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; x represents an integer of 3 to 10, and y represents an integer of 1 to 100.

[0108] In order for the silane coupling agent (a) having a polymerizable group to react without being deactivated, the reaction temperature must be 180° C. or lower, and therefore the boiling point of the end-capping agent (b) must be 180° C. or lower, preferably 170° C. or lower, more preferably 160° C. or lower, even more preferably 155° C. or lower, and most preferably 150° C. or lower. From the viewpoint of handleability, the boiling point of the end-capping agent (b) is preferably 50° C. or higher, more preferably 60° C. or higher, even more preferably 70° C. or higher, and most preferably 80° C. or higher.

[0109] The surface-treated dental filler (C-1) is surface-treated with the end-capping agent (b), which prevents the deactivation of the polymerizable group of the silane coupling agent (a), provides excellent acid resistance, and prevents reaction with a polymerizable monomer having an acidic group. Therefore, even when a dental composition containing a polymerizable monomer having an acidic group contains a radiopaque filler, it has excellent storage stability even under harsh conditions (e.g., 60°C for 4 weeks). This is advantageous in that the type of filler (C) is not limited. Furthermore, the surface treatment using the end-capping agent (b) can prevent the deactivation of the polymerizable group of the silane coupling agent (a), and there is no circumstance in which other components to be blended interfere with the effect of the end-capping agent (b). Therefore, even when used as a dental cement, a dental bonding material (e.g., an orthodontic bonding material, etc.), a dental composite resin (e.g., a self-adhesive dental composite resin, etc.), a pit and fissure sealant, a loose tooth fixation material, a dental abutment construction material, etc., the dental composition of the present invention can achieve the effect of having excellent storage stability under harsh conditions and the cured product having sufficient mechanical strength.

[0110] R in terms of reactivity and boiling point １ ~R ６ The number of carbon atoms in the alkyl group is preferably 1 to 5, more preferably 1 to 4, even more preferably 1 or 2, and most preferably 1. x is preferably 3 to 6, more preferably 3 to 5, even more preferably 3 or 4, and most preferably 3. y is preferably 1 to 10, more preferably 1 to 4, even more preferably 1 or 2, and most preferably 1. m is preferably 1 to 5, more preferably 1 to 4, even more preferably 1 or 2, and most preferably 1.

[0111] R １ ~R ６ The alkyl group having 1 to 9 carbon atoms may be linear or branched, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a neopentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, and an n-nonyl group.

[0112] A preferred embodiment of the dental composition includes an end-capping agent (b) that has a cyclic siloxane structure represented by general formula (1) and has a boiling point of 180°C or lower.

[0113] Another preferred embodiment includes a dental composition in which the end-capping agent (b) is a compound having a structure represented by general formula (2) and a boiling point of 180° C. or lower.

[0114] In one embodiment, in the structure represented by general formula (2), R １ ~R ６ are each independently preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, still more preferably a hydrogen atom, a methyl group, or an ethyl group, and most preferably a hydrogen atom or a methyl group.

[0115] In another embodiment, in the structure represented by general formula (2), R １ ~R ６ When R is an alkyl group having 1 to 9 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, the number of SiH groups is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, and most preferably 5 or more. １ ~R ６ When contains an alkoxy group, it is preferred that there are two or more alkoxy groups directly bonded to the silicon atom.

[0116] In still other embodiments, R １ ~R ６ is preferably an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, still more preferably an alkyl group having 1 to 2 carbon atoms or an alkoxy group having 1 to 2 carbon atoms, and most preferably an alkoxy group having 1 carbon atom or an alkyl group having 1 carbon atom. In the structure represented by general formula (2), R １ ~R ６When at least one of the groups is an alkoxy group, the number of alkoxy groups is preferably 3 or more, more preferably 4 or more, even more preferably 5 or more, and most preferably 6 or more.

[0117] Specific examples of the endcapping agent (b) include hexamethylcyclotrisiloxane (boiling point: 134°C), octamethylcyclotetrasiloxane (boiling point: 175°C), 1,1,3,3-tetramethyldisiloxane (boiling point: 71°C), 1,1,3,3,5,5-hexamethyltrisiloxane (boiling point: 128°C), and 1,3-dimethoxytetramethyldisiloxane. The endcapping agent (b) may be used alone or in combination of two or more. Among these, hexamethylcyclotrisiloxane is preferred from the viewpoint of reactivity, etc.

[0118] The filler (filler before surface treatment) used in the dental surface-treated filler (C-1) is not particularly limited, but examples thereof include the inorganic fillers and organic-inorganic composite fillers described above as the filler (C), among which inorganic fillers are preferred. Specific examples of preferred inorganic filler materials include various glasses (mainly composed of silica, and optionally containing oxides of heavy metals, boron, aluminum, etc.). For example, glass powders of general compositions such as fused silica, quartz, soda lime silica glass, E glass, C glass, borosilicate glass (Pyrex (registered trademark) glass), etc., dental glass powders such as barium glass (GM27884, 8235, manufactured by SCHOTT, E-2000, E-3000, manufactured by ESSTECH), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by SCHOTT), fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by SCHOTT), composite oxides such as silica-titania and silica-zirconia, silica-zirconia oxide aggregate filler, ytterbium fluoride, ytterbium fluoride with a core-shell structure surface-coated with silica, ytterbium fluoride with a core-shell structure surface-coated with silica, Examples of suitable fillers include barium fluoride having a core-shell structure coated with silica, barium sulfate, zirconium dioxide, barium sulfate having a core-shell structure coated with silica, and zirconium dioxide having a core-shell structure coated with silica. Among these, from the viewpoint of radiopacity, preferred are radiopaque fillers such as barium glass, lanthanum glass ceramics, fluoroaluminosilicate glass, composite oxides such as silica-titania and silica-zirconia, ytterbium fluoride, ytterbium fluoride having a core-shell structure coated with silica, yttrium fluoride having a core-shell structure coated with silica, barium sulfate, zirconium dioxide, barium sulfate having a core-shell structure coated with silica, and zirconium dioxide having a core-shell structure coated with silica. Note that "radiopacity" refers to the property of a substance that allows X-rays to not pass through, and radiopaque areas appear white in an X-ray photograph.As used herein, "radiopacity" refers to the ability to distinguish between natural tooth tissue and a hardened dental composition using a standard dental X-ray device in a conventional manner. When a dental composition contains a radiopaque filler, the dental composition exhibits radiopacity and is therefore more suitable for use when diagnosing dental conditions using X-rays than a dental composition that does not contain a radiopaque filler. Furthermore, from the standpoint of mechanical strength, barium glass, strontium borosilicate glass, lanthanum glass ceramics, fluoroaluminosilicate glass, composite oxides such as silica-zirconia, ytterbium fluoride having a core-shell structure coated with silica, and silica-zirconia oxide agglomerated fillers are preferred, with barium glass, strontium borosilicate glass, lanthanum glass ceramics, fluoroaluminosilicate glass, ytterbium fluoride having a core-shell structure coated with silica, and silica-zirconia oxide agglomerated fillers being more preferred. These fillers may be used alone or in combination of two or more.

[0119] The surface-treated dental filler (C-1) is obtained by reacting (dehydration condensation) a silane coupling agent (a) having a polymerizable group and an end-capping agent (b) with hydroxyl groups on the filler surface. Carrying out this reaction is referred to as "surface treatment." The process of performing the surface treatment is also referred to as the "surface treatment process."

[0120] By treating the surface with the end-capping agent (b), the end-capping agent (b) reacts with hydroxyl groups (unreacted hydroxyl groups) that are present on the surface of the filler and that have not been completely reacted with the silane coupling agent (a).

[0121] The order of surface treatments for obtaining the dental surface-treated filler (C-1) is not particularly limited. For example, the filler may be surface-treated by adding the silane coupling agent (a) and the end-capping agent (b) in that order, or by adding them simultaneously. The order of surface treatments may be, for example, to first react the filler with the silane coupling agent (a), followed by reaction with a specific end-capping agent (b). Alternatively, the filler may be first reacted with the end-capping agent (b), followed by reaction with the silane coupling agent (a). From the viewpoint of further increasing the surface coverage by the silane coupling agent (a) and the end-capping agent (b), a method of first reacting the filler with the silane coupling agent (a), followed by reaction with the end-capping agent (b) is preferred. In one embodiment, a dental surface-treated filler (C-1) may be surface-treated with a silane coupling agent (a) having a polymerizable group, followed by surface treatment with the end-capping agent (b).

[0122] The surface treatment method for obtaining the dental surface-treated filler (C-1) is not particularly limited, as long as it is a method in which a silane coupling agent (a) is bonded to the surface of the filler by a dehydration polycondensation reaction, or a method in which an end-capping agent (b) is bonded to the surface of the filler. Examples of reactions using the silane coupling agent (a) include a method in which, while stirring the filler in a mixing tank, a solution of a surface treatment agent containing the silane coupling agent (a) (preferably only the silane coupling agent (a)) diluted with a solvent is sprayed, and the mixture is heated and dried in the tank for a certain period of time while continuing to stir; a method in which the filler and a surface treatment agent containing the silane coupling agent (a) (preferably only the silane coupling agent (a)) are stirred and mixed in a solvent, and then heated and dried. The solvent is not particularly limited, but examples include alcoholic solvents such as methanol, ethanol, and isopropanol; water; or a mixture thereof. Furthermore, in the surface treatment with the silane coupling agent (a), it is preferable to use a solvent containing an acid (e.g., acetic acid, etc.) (e.g., an aqueous acetic acid solution) because the reaction (hydrolysis reaction and dehydration condensation reaction) proceeds quickly in an acidic environment. The heating temperature is not particularly limited, but may be about 30 to 90°C. Examples of the reaction with the endcapping agent (b) include a method in which a surface treatment agent containing the endcapping agent (b) (preferably only the endcapping agent (b)) is vaporized and subjected to a gas-phase reaction with the filler. The reaction temperature is not particularly limited and can be changed appropriately depending on the boiling point of the endcapping agent (b), but a temperature of 130 to 180°C is preferred.

[0123] In the production of the surface-treated dental filler (C-1), it is preferable to carry out an acid treatment step (hereinafter sometimes simply referred to as an "acid treatment step") before the surface treatment from the viewpoints of increasing the number of reactive sites, removing polyvalent metals, and improving storage stability. The polyvalent metals on the filler surface are removed by the acid, making it possible to suppress adsorption of the polymerizable monomer (A-1) having an acidic group.

[0124] The acid used in the acid treatment step is not particularly limited and may be an organic acid or an inorganic acid. Examples of inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, and sulfonic acid. Examples of organic acids include formic acid, acetic acid, propionic acid, oxalic acid, citric acid, and tartaric acid. Among these, inorganic acids are preferred, and hydrochloric acid is more preferred, because they are easy to remove after treatment.

[0125] The method of the acid treatment is not particularly limited as long as it is a method that brings the filler into contact with the acid, but for example, a method in which the filler is stirred in an acidic aqueous solution is preferred.

[0126] The concentration of the acidic aqueous solution used in the acid treatment step is preferably 1 to 20% by mass, more preferably 1 to 10% by mass, and the amount of the acidic aqueous solution having the above concentration is preferably 100 to 1,000 parts by mass per 100 parts by mass of the filler.

[0127] The acid treatment temperature in the acid treatment step is not particularly limited, but is preferably 10 to 60° C. The treatment time can be appropriately set depending on the acid treatment temperature and the type and amount of acid used. The acid treatment step may be repeated.

[0128] The filler that has been subjected to an acid treatment (hereinafter sometimes simply referred to as "acid-treated product") may be subjected to a step of washing the acid-treated product and / or a step of adjusting the pH of the acid-treated product or a solution containing the acid-treated product to near neutral. The washing step (hereinafter sometimes simply referred to as "washing step") is a step of washing the acid remaining on the surface of the acid-treated product with water. The washing step can be repeated until the remaining acid is removed. If a large amount of acid remains, the surface treatment may not be performed properly in the surface treatment step. Examples of steps of adjusting the pH of the acid-treated product or a solution containing the acid-treated product to near neutral include a method of adding a pH adjuster (such as sodium bicarbonate) and a method of approaching neutrality by repeatedly washing with water and filtering.

[0129] In the surface treatment step for producing a dental surface-treated filler (C-1), a silane coupling agent (a) is first reacted with a filler, and then an end-capping agent (b) is reacted. Since it is estimated that unreacted reactive groups (hydroxyl groups or hydrolyzable groups) remain on the filler even after the reaction of the silane coupling agent (a), it is preferable to subject the filler surface-treated with the silane coupling agent (a) to a hydrolysis treatment step from the viewpoint of increasing the reactivity of the end-capping agent (b). Examples of the hydrolysis treatment step include a method in which a filler surface-treated with the silane coupling agent (a) is diluted with an acetic acid solution (aqueous acetic acid or a mixture of water and an organic solvent in which acetic acid is dissolved) and then subjected to a hydrolysis reaction. Another embodiment includes a dental surface-treated filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and then hydrolyzed.

[0130] A filler that has been surface-treated with the silane coupling agent (a) (preferably a filler that has been surface-treated with the silane coupling agent (a) and hydrolyzed) can be subjected to a surface treatment step with the end-capping agent (b).

[0131] By surface-treating the dental surface-treated filler (C-1) with a specific end-capping agent (b), it is possible to reduce unreacted hydrolyzable groups (e.g., unreacted hydroxyl groups) after the reaction with the silane coupling agent (a), thereby reducing the reactivity between the filler and polymerizable monomers (particularly polymerizable monomers having acidic groups) in the dental composition. As a result, a dental composition with excellent storage stability can be obtained, even under harsh conditions (e.g., 4 weeks at 60°C). Furthermore, the dental surface-treated filler (C-1) has sufficient polymerizable groups on its surface derived from the silane coupling agent (a) to ensure mechanical strength, and therefore the cured product has sufficient mechanical strength. As long as unreacted hydrolyzable groups (e.g., unreacted hydroxyl groups) can be reduced, the effects of the present invention can be achieved in compositions containing a filler and a polymerizable monomer (particularly a polymerizable monomer having an acidic group), regardless of the specific dental application.

[0132] After the surface treatment of the filler, the silane coupling agent (a) and end-capping agent (b) are present on the surface of the filler, but are not chemically bonded to the surface of the filler. From the viewpoint of storage stability, it is preferable to include a step of washing the physically adsorbed components. As a method for washing the physically adsorbed silane coupling agent (a) and end-capping agent (b), a method of dissolving the physically adsorbed material in a solvent and then removing the solvent using a hollow fiber membrane or filter paper, etc., can be mentioned. The washing solvent is not particularly limited, but examples thereof include alcoholic solvents such as methanol, ethanol, and isopropanol; acetonitrile; water; or a mixture thereof.

[0133] The amount of the silane coupling agent (a) used to treat the filler in the surface treatment step to obtain the surface-treated dental filler (C-1) is preferably 0.5 to 40 parts by mass, more preferably 1 to 20 parts by mass, and even more preferably 2 to 10 parts by mass, per 100 parts by mass of the filler before surface treatment. If the amount is less than 0.5 parts by mass, it may be impossible to impart sufficient polymerizable groups to the surface of the filler, resulting in a decrease in mechanical strength. If the amount is more than 40 parts by mass, the excess silane coupling agent (a) may reduce the mechanical strength of the cured product.

[0134] The amount of the end-capping agent (b) used to treat the filler in the surface treatment step to obtain the surface-treated dental filler (C-1) is preferably 0.01 to 20 parts by mass, more preferably 0.05 to 15 parts by mass, and even more preferably 0.1 to 10 parts by mass, relative to 100 parts by mass of the filler before surface treatment. If the amount is less than 0.01 part by mass, a sufficient amount of surface treatment cannot be performed on the surface of the filler, and storage stability may not be ensured. If the amount is more than 20 parts by mass, the excess end-capping agent (b) may reduce the mechanical strength of the cured product.

[0135] In the surface treatment, a polymerization inhibitor may be added to suppress polymerization of the silane coupling agent (a). Known polymerization inhibitors such as 3,5-dibutyl-4-hydroxytoluene (BHT) and p-methoxyphenol (methoquinone) can be used.

[0136] The surface treatment agent used in the surface treatment to obtain the surface-treated dental filler (C-1) preferably contains only a silane coupling agent (a) and an end-capping agent (b). Surface treatment agents other than the silane coupling agent (a) and the end-capping agent (b) may be used in combination, provided that the effects of the present invention are not impaired. Examples of such surface treatment agents include organosilazanes such as 1,1,1,3,3,3-hexamethyldisilazane.

[0137] Drying to obtain the surface-treated dental filler (C-1) can be carried out by a conventional method, such as heating or leaving it under reduced pressure (vacuum). There are no particular limitations on the heating device or pressure reducing device, and known devices can be used.

[0138] A preferred embodiment of the dental composition includes a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), in which the filler (C) includes a surface-treated dental filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and the end-capping agent (b) is a compound having a structure represented by the above formula (1) or (2) and having a boiling point of 180°C or lower.

[0139] One embodiment of the present invention includes a surface-treated dental filler (C-1) in which the filler is surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and the end-capping agent (b) is a compound having a structure represented by formula (1) or (2) and having a boiling point of 180° C. or lower. Another preferred embodiment includes a surface-treated dental filler (C-1) in which the filler includes an inorganic filler.

[0140] The dental composition of the present invention may contain only the dental surface-treated filler (C-1) as the filler (C). Alternatively, the dental composition may contain two or more types of dental surface-treated fillers (C-1). In the dental composition of the present invention, the content of the dental surface-treated filler (C-1) is 50 to 2,000 parts by mass, preferably 100 to 1,000 parts by mass, more preferably 125 to 750 parts by mass, and even more preferably 150 to 500 parts by mass, per 100 parts by mass of the monomer component. In another embodiment, the filler (C) may contain the dental surface-treated filler (C-1) and a filler other than the dental surface-treated filler (C-1). The filler other than the dental surface-treated filler (C-1) may be used alone or in combination of two or more types. In the above embodiment, the mass ratio of the dental surface-treated filler (C-1) to the filler other than the dental surface-treated filler (C-1) is preferably 10:1 to 1:10, more preferably 8:1 to 1:8, and even more preferably 1:5 to 5:1. The content of the filler (C) is not particularly limited, but the preferred content varies depending on the application of the dental composition, as described below.

[0141] The method for producing the dental composition of the present invention is not particularly limited as long as it is a dental composition containing a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), and containing a surface-treated dental filler (C-1) in which the filler (C) has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and the dental composition can be easily produced by a method known to those skilled in the art (e.g., mixing, kneading, etc.). Examples of the method for producing the dental composition of the present invention include a method comprising a step of obtaining the surface-treated dental filler (C-1), the step including a step of surface-treating the filler with a silane coupling agent (a) having a polymerizable group and a step of surface-treating the filler with an end-capping agent (b).

[0142] <Polymerization Accelerator (D)> The dental composition of the present invention can use a polymerization accelerator (D) together with the polymerization initiator (B). Examples of the polymerization accelerator (D) used in the present invention include amines, sulfinic acid and its salts, borate compounds, barbituric acid compounds, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds.

[0143] Amines used as the polymerization accelerator (D) are divided into aliphatic amines and aromatic amines. Examples of aliphatic amines include primary aliphatic amines such as n-butylamine, n-hexylamine, and n-octylamine; secondary aliphatic amines such as diisopropylamine, dibutylamine, and N-methylethanolamine; and tertiary aliphatic amines such as N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, tertiary aliphatic amines are preferred from the viewpoints of the curability and storage stability of the dental composition, and N-methyldiethanolamine and triethanolamine are more preferably used.

[0144] Examples of aromatic amines include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis(2-hydroxyethyl)-4-ethylaniline, N,N-bis(2-hydroxyethyl)-4-isopropylaniline, N,N-bis(2-hydroxyethyl)-4-t-butylaniline, N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, and N,N-diethyl-p -toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, N,N-dimethyl-3,5-di-t-butylaniline, 4-(N,N-dimethylamino)ethyl benzoate, 4-(N,N-dimethylamino)methyl benzoate, 4-(N,N-dimethylamino)propyl benzoate, 4-(N,N-dimethylamino)n-butoxyethyl benzoate, 4-(N,N-dimethylamino)2-(methacryloyloxy)ethyl benzoate, 4-(N,N-dimethylamino)benzophenone, and 4-(N,N-dimethylamino)butyl benzoate. Among these, at least one selected from the group consisting of N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone is preferably used from the viewpoint of being able to impart excellent curability to the dental composition.

[0145] Specific examples of sulfinic acids and salts thereof, borate compounds, barbituric acid compounds, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds include those described in WO 2008 / 087977.

[0146] The polymerization accelerator (D) may be contained alone or in combination of two or more. The content of the polymerization accelerator (D) used in the present invention is not particularly limited. However, from the viewpoint of the curability of the resulting dental composition, the content is preferably 0.001 to 30 parts by mass, more preferably 0.01 to 10 parts by mass, even more preferably 0.05 to 20 parts by mass, and particularly preferably 0.1 to 5 parts by mass, per 100 parts by mass of the polymerizable monomer (A) in the dental composition. When the content of the polymerization accelerator (D) is 0.001 part by mass or more, polymerization proceeds sufficiently and the desired adhesiveness is obtained, and a content of 0.05 part by mass or more is more preferred. On the other hand, when the content of the polymerization accelerator (D) is 30 parts by mass or less, sufficient adhesiveness is obtained, and therefore a content of 20 parts by mass or less is more preferred.

[0147] <Fluoride ion-releasing substance> The dental composition of the present invention may further contain a fluoride ion-releasing substance. By containing a fluoride ion-releasing substance, a dental composition capable of imparting acid resistance to tooth structure can be obtained. Examples of such fluoride ion-releasing substances include metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride. The above fluoride ion-releasing substances may be contained alone or in combination of two or more.

[0148] The dental composition of the present invention may contain known additives within the range that does not impair the performance. Such additives include polymerization inhibitors, antioxidants, pigments, dyes, ultraviolet absorbers, organic solvents, thickeners, etc. One type of additive may be used alone, or two or more types may be used in combination.

[0149] 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, 3,5-di-t-butyl-4-hydroxytoluene, etc. The content of the polymerization inhibitor is preferably 0.001 to 1.0 part by mass per 100 parts by mass of the polymerizable monomer (A) in the dental composition.

[0150] <Solvent> In an embodiment, the dental composition of the present invention may contain a solvent. Examples of the solvent include water and an organic solvent. The solvent is preferably used in the form of a mixed solvent of water and an organic solvent. In some embodiments, the inclusion of the organic solvent may not be necessary.

[0151] The dental composition of the present invention contains water, which promotes the decalcifying action of the polymerizable monomer (A-1) having an acidic group on tooth structure. The water used must be substantially free of impurities that adversely affect adhesiveness, and distilled water or ion-exchanged water is preferred. If the water content is too low, the decalcifying action promotion effect may not be sufficiently achieved, while if the water content is too high, adhesiveness may decrease. The content of water in the solvent is preferably 1 to 500 parts by mass, more preferably 5 to 300 parts by mass, and even more preferably 10 to 200 parts by mass, per 100 parts by mass of the polymerizable monomer (A) in the dental composition.

[0152] When the dental composition of the present invention contains an organic solvent, the adhesiveness, coatability, and penetration into tooth tissue can be further improved, and separation of the components of the composition can be further prevented. The organic solvent usually has a boiling point of 150°C or less under normal pressure and a solubility in water at 25°C of 5% by mass or more, preferably 30% by mass or more, and more preferably is soluble in water in any proportion.

[0153] Examples of organic solvents include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-2-propanol, acetone, methyl ethyl ketone, tetrahydrofuran, diethyl ether, diisopropyl ether, hexane, toluene, chloroform, ethyl acetate, butyl acetate, etc. Among these, when taking into consideration both safety to living organisms and ease of removal based on volatility, it is preferable that the organic solvent is a water-soluble organic solvent, and specifically, ethanol, 2-propanol, 2-methyl-2-propanol, acetone, and tetrahydrofuran are preferred, and ethanol, 2-propanol, 2-methyl-2-propanol, and tetrahydrofuran are more preferred.

[0154] In one embodiment, the total content of the solvent is preferably 1 to 2,000 parts by mass, more preferably 2 to 1,000 parts by mass, and even more preferably 3 to 500 parts by mass, per 100 parts by mass of the polymerizable monomer (A) in the dental composition.

[0155] In one embodiment, the dental composition of the present invention preferably contains the components so that the pH of the liquid (composition) is in the range of 1.5 to 4.0, more preferably 1.8 to 3.5, and even more preferably 2.0 to 3.0. If the pH of the composition is less than 1.5, excessive demineralization may occur during total etching, in which the composition is applied to the tooth surface after phosphoric acid etching, potentially resulting in reduced adhesion. On the other hand, if the pH of the composition exceeds 4.0, the reduced demineralization effect may result in reduced adhesion during self-etching.

[0156] The dental composition of the present invention can be used in dental treatments such as dental cements, dental bonding materials (e.g., orthodontic bonding materials), dental composite resins (e.g., self-adhesive dental composite resins), pit and fissure sealants, materials for fixing loose teeth, and dental core buildup materials. Among these, the dental composition is particularly suitable for use as a self-adhesive dental composite resin, dental cement, dental composite resin (excluding self-adhesive dental composite resins), dental core buildup materials, or dental bonding materials. Even in these applications, the dental surface treatment filler (C-1) provides excellent acid resistance and prevents reaction with polymerizable monomers (particularly polymerizable monomers having acidic groups). Furthermore, there is no circumstance in which the effects of the dental surface treatment filler (C-1) are impaired by other components that are blended. Therefore, the dental composition has excellent storage stability even under harsh conditions (e.g., 60°C for 4 weeks). Furthermore, by including the dental surface-treated filler (C-1), the dental composition has a surface with polymerizable groups derived from the silane coupling agent (a) that are sufficient to ensure mechanical strength, and therefore the cured product has sufficient mechanical strength in the above-mentioned applications. In these applications, the dental composition of the present invention may be used in a one-bottle or one-paste form in which the components are combined into one, or in a two-bottle or two-paste form in which the components are separated into two. Specific embodiments of the dental composition when used are described below.

[0157] <Self-Adhesive Dental Composite Resin> One preferred embodiment of the dental composition of the present invention is a self-adhesive dental composite resin. When the dental composition of the present invention is used as a self-adhesive dental composite resin, it contains a polymerizable monomer (A), a polymerization initiator (B), a dental surface treatment filler (C-1), and a polymerization accelerator (D), and preferably the polymerizable monomer (A) contains a polymerizable monomer (A-1) having an acidic group, a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and a hydrophilic polymerizable monomer (A-2b) not having an acidic group. Furthermore, the polymerization initiator (B) preferably contains a photopolymerization initiator, and more preferably the polymerization initiator (B) contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2). When the dental composition of the present invention is used as a self-adhesive dental composite resin, a pretreatment material may be used; however, due to the self-adhesive properties, a pretreatment material is not essential and may not be used. A self-adhesive dental composite resin can be produced which does not contain a pretreatment material and is composed solely of the dental composition of the present invention.

[0158] The content of each component in the self-adhesive dental composite resin is preferably 1 to 50 parts by mass of a polymerizable monomer (A-1) having an acidic group, 20 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 0 to 50 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group, per 100 parts by mass of the polymerizable monomer (A) in the dental composition. parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 0 to 40 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group, and more preferably, 1 to 30 parts by mass of a polymerizable monomer (A-1) having an acidic group, 60 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 0 to 30 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group. Furthermore, the dental composition preferably contains 0.001 to 30 parts by mass of a polymerization initiator (B), 50 to 2,000 parts by mass of a dental surface-treated filler (C-1), and 0.001 to 20 parts by mass of a polymerization accelerator (D) relative to 100 parts by mass of the polymerizable monomer (A), and more preferably contains 0.05 to 10 parts by mass of the polymerization initiator (B), 100 to 1,000 parts by mass of a dental surface-treated filler (C-1), and 0.05 to 10 parts by mass of a polymerization accelerator (D). The dental composition used as a self-adhesive dental composite resin does not need to contain the hydrophilic polymerizable monomer (A-2b).

[0159] <Dental Cement> Another preferred embodiment of the dental composition of the present invention is a dental cement. Suitable examples of dental cements include resin cement, glass ionomer cement, and resin-reinforced glass ionomer cement. When using dental cement, a self-etching primer or the like may be used first as a pretreatment agent. When the dental composition of the present invention is used as a dental cement, it contains a polymerizable monomer (A), a polymerization initiator (B), a dental surface treatment filler (C-1), and a polymerization accelerator (D), and it is preferred that the polymerizable monomer (A) contains a polymerizable monomer (A-1) having an acidic group, a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and a hydrophilic polymerizable monomer (A-2b) not having an acidic group. Furthermore, it is preferred that the polymerization initiator (B) contains a chemical polymerization initiator, and it is more preferred that a chemical polymerization initiator and a photopolymerization initiator are used in combination. It is preferred that a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2) are used in combination as photopolymerization initiators.

[0160] The content of each component in the dental cement is preferably 0 to 50 parts by mass of a polymerizable monomer (A-1) having an acidic group, 50 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and 0 to 50 parts by mass of a hydrophilic polymerizable monomer (A-2b) not having an acidic group, per 100 parts by mass of the polymerizable monomer (A) in the dental composition. It is more preferable that the composition contains 60 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group and 0 to 40 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group, and it is even more preferable that the composition contains 0 to 30 parts by mass of a polymerizable monomer (A-1) having an acidic group, 70 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 0 to 30 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group. Furthermore, the composition preferably contains 0.001 to 30 parts by mass of a polymerization initiator (B), 50 to 2,000 parts by mass of a dental surface-treating filler (C-1), and 0.001 to 20 parts by mass of a polymerization accelerator (D) relative to 100 parts by mass of the polymerizable monomer (A), and more preferably contains 0.05 to 10 parts by mass of a polymerization initiator (B), 100 to 1,500 parts by mass of a dental surface-treating filler (C-1), and 0.05 to 10 parts by mass of a polymerization accelerator (D). The composition may not contain a hydrophilic polymerizable monomer (A-2b), and in the case of a type that uses a pretreatment material, the composition may not contain a polymerizable monomer (A-1) having an acidic group.

[0161] <Dental Bonding Material> One preferred embodiment of the dental composition of the present invention is a dental bonding material. This dental bonding material allows the decalcification process, penetration process, and curing process to be performed in a single step. Examples of dental bonding materials include a two-bottle type in which two separate parts, Part A and Part B, are mixed immediately before use, and a one-bottle type in which one part can be used as is. Among these, the one-bottle type offers greater advantages in terms of simplifying the process. The dental bonding material may also use a self-etching primer or the like as a pretreatment material. The dental composition used in this dental bonding material preferably contains a polymerizable monomer (A), a polymerization initiator (B), a dental surface treatment filler (C-1), and a polymerization accelerator (D), and the polymerizable monomer (A) preferably contains a polymerizable monomer (A-1) having an acidic group, a hydrophobic polymerizable monomer (A-2a) having no acidic group, a hydrophilic polymerizable monomer (A-2b) having no acidic group, and a solvent. The polymerization initiator (B) preferably contains a photopolymerization initiator, and more preferably contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2).

[0162] The content of each component in the dental bonding material is preferably 1 to 90 parts by mass of a polymerizable monomer (A-1) having an acidic group, 40 to 96 parts by mass of a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and 3 to 50 parts by mass of a hydrophilic polymerizable monomer (A-2b) not having an acidic group, relative to 100 parts by mass of the polymerizable monomer (A) in the dental composition, and 1 to 40 parts by mass of the polymerizable monomer (A-1) having an acidic group, It is more preferable that the composition contains 50 to 90 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group and 5 to 40 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group, and it is even more preferable that the composition contains 5 to 30 parts by mass of a polymerizable monomer (A-1) having an acidic group, 60 to 80 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 15 to 35 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group. Furthermore, it is preferable that the composition contains 0.001 to 30 parts by mass of a water-soluble photopolymerization initiator (B-1), 0.001 to 30 parts by mass of a water-insoluble photopolymerization initiator (B-2), 0.001 to 20 parts by mass of a polymerization accelerator (D), 1 to 100 parts by mass of a dental surface-treated filler (C-1), and 1 to 2,000 parts by mass of a solvent, relative to 100 parts by mass of the polymerizable monomer (A). It is more preferable that the composition contains 0.05 to 10 parts by mass of a water-soluble photopolymerization initiator (B-1), 0.05 to 10 parts by mass of a water-insoluble photopolymerization initiator (B-2), 0.05 to 10 parts by mass of a polymerization accelerator (D), 3 to 75 parts by mass of a dental surface-treated filler (C-1), and 2 to 1,000 parts by mass of a solvent.

[0163] <Dental Composite Resin> One preferred embodiment of the dental composition of the present invention is a dental composite resin (excluding self-adhesive dental composite resins). When the dental composition of the present invention is used as a dental composite resin, it contains a polymerizable monomer (A), a polymerization initiator (B), a dental surface treatment filler (C-1), and a polymerization accelerator (D). Furthermore, the polymerization initiator (B) preferably contains a photopolymerization initiator, and it is more preferable that the polymerization initiator (B) contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2).

[0164] The content of each component in the dental composite resin is preferably 20 to 100 parts by mass of the hydrophobic polymerizable monomer (A-2a) not having an acidic group and 0 to 80 parts by mass of the hydrophilic polymerizable monomer (A-2b) not having an acidic group, more preferably 40 to 100 parts by mass of the hydrophobic polymerizable monomer (A-2a) not having an acidic group and 0 to 40 parts by mass of the hydrophilic polymerizable monomer (A-2b) not having an acidic group, and even more preferably 60 to 100 parts by mass of the hydrophobic polymerizable monomer (A-2a) not having an acidic group and 0 to 30 parts by mass of the hydrophilic polymerizable monomer (A-2b) not having an acidic group, per 100 parts by mass of the polymerizable monomer (A) in the dental composition. Furthermore, the dental composition preferably contains 0.001 to 30 parts by mass of a polymerization initiator (B), 50 to 2,000 parts by mass of a dental surface-treated filler (C-1), and 0.001 to 20 parts by mass of a polymerization accelerator (D), relative to 100 parts by mass of the polymerizable monomer (A), and more preferably contains 0.05 to 10 parts by mass of the polymerization initiator (B), 100 to 1,500 parts by mass of a dental surface-treated filler (C-1), and 0.05 to 10 parts by mass of a polymerization accelerator (D). The dental composition used as a dental composite resin does not need to contain the hydrophilic polymerizable monomer (A-2b).

[0165] <Dental Core Construction Material> Another preferred embodiment of the dental composition of the present invention is a dental core construction material. Resin cement is a suitable example of a dental core construction material. A self-etching primer or the like may be used as a pretreatment agent for the dental core construction material. When the dental composition of the present invention is used as a dental core construction material, it contains a polymerizable monomer (A), a polymerization initiator (B), a dental surface treatment filler (C-1), and a polymerization accelerator (D). The polymerizable monomer (A) preferably contains a polymerizable monomer (A-1) having an acidic group, a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and a hydrophilic polymerizable monomer (A-2b) not having an acidic group. The polymerization initiator (B) preferably contains a chemical polymerization initiator, and more preferably a combination of a chemical polymerization initiator and a photopolymerization initiator. The photopolymerization initiator preferably contains a water-soluble photopolymerization initiator (B-1) and a water-insoluble photopolymerization initiator (B-2).

[0166] The content of each component in the dental core material is preferably 0 to 50 parts by mass of a polymerizable monomer (A-1) having an acidic group, 50 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) not having an acidic group, and 0 to 50 parts by mass of a hydrophilic polymerizable monomer (A-2b) not having an acidic group, relative to 100 parts by mass of the polymerizable monomer (A) in the dental composition, and 0 to 40 parts by mass of a polymerizable monomer (A-1) having an acidic group, It is more preferable that the composition contains 60 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group and 0 to 40 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group, and it is even more preferable that the composition contains 0 to 30 parts by mass of a polymerizable monomer (A-1) having an acidic group, 70 to 99 parts by mass of a hydrophobic polymerizable monomer (A-2a) having no acidic group, and 0 to 30 parts by mass of a hydrophilic polymerizable monomer (A-2b) having no acidic group. Furthermore, the composition preferably contains 0.001 to 30 parts by mass of a polymerization initiator (B), 50 to 2,000 parts by mass of a dental surface-treating filler (C-1), and 0.001 to 20 parts by mass of a polymerization accelerator (D) relative to 100 parts by mass of the polymerizable monomer (A), and more preferably contains 0.05 to 10 parts by mass of the polymerization initiator (B), 100 to 1,500 parts by mass of a dental surface-treating filler (C-1), and 0.05 to 10 parts by mass of a polymerization accelerator (D). The composition may not contain the hydrophilic polymerizable monomer (A-2b), and in the case of a type that uses a pretreatment material, the composition may not contain the polymerizable monomer (A-1) having an acidic group.

[0167] In any of the preferred embodiments of the above-mentioned self-adhesive dental composite resin, dental cement, dental composite resin, dental abutment construction material, and dental bonding material, the content of each component can be changed as appropriate based on the explanations in the above specification, and any component can be added, deleted, or otherwise modified.

[0168] 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.

[0169] 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. In the examples, parts are by mass unless otherwise specified.

[0170] Next, the components of the dental compositions of the Examples and Comparative Examples are listed below together with their abbreviations.

[0171] [Polymerizable Monomer (A-1) Having an Acidic Group] MDP: 10-methacryloyloxydecyl dihydrogen phosphate

[0172] [Polymerizable monomer (A-2) having no acidic group] D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6) 3G: triethylene glycol dimethacrylate MAEA: N-methacryloyloxyethyl acrylamide

[0173] [Polymerization initiator (B)] Water-soluble photopolymerization initiator (B-1) Li-TPO: lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate Water-insoluble photopolymerization initiator (B-2) CQ: camphorquinone

[0174] [Dental Surface-Treated Filler (C-1)] Production Example 1: Production of Filler 1 Hydrochloric Acid Treatment Step 100 g of 8235 UF0.7 grade (barium glass manufactured by SCHOTT, average particle size: 0.7 μm) and 500 mL of a 5% by weight aqueous hydrochloric acid solution were added to a beaker, stirred at room temperature for 30 minutes, and the aqueous hydrochloric acid solution was removed by vacuum filtration. Next, 500 mL of distilled water and the filler (acid-treated product) were added again to the beaker, stirred at room temperature for 30 minutes, and the aqueous solution was removed by vacuum filtration. This washing step was repeated three times, followed by vacuum drying. Surface Treatment Step with Silane Coupling Agent (a) 100 g of the hydrochloric acid-treated filler, 10 g of 3-methacryloyloxypropyltrimethoxysilane, and 200 mL of a 0.3% by weight aqueous acetic acid solution were placed in a three-neck flask and stirred at room temperature for 2 hours. After removing the water by freeze-drying, the mixture was heat-treated at 80°C for 5 hours. Next, 500 mL of ethanol and 100 g of filler (filler that has been surface-treated with the silane coupling agent (a)) were added to a beaker, stirred at room temperature for 30 minutes, and a washing process of removing the solution by vacuum filtration was repeated three times, followed by vacuum drying. - Hydrolysis Treatment Step: 100 g of the filler that has been surface-treated with the silane coupling agent (a) and a 5% by mass acetic acid solution (5 g of acetic acid, 100 mL of a water / ethanol mixed solution (50:50 (v / v))) were added to a beaker, stirred at room temperature for 30 minutes, and then the solvent was removed by vacuum filtration. Next, 500 mL of a separately prepared water / ethanol mixed solution (50:50 (v / v)) and the filler (filler that has undergone hydrolysis treatment) were added to a beaker, stirred at room temperature for 30 minutes, and a washing process of removing the solvent by vacuum filtration was repeated three times, followed by vacuum drying. Surface Treatment Step with Endcapping Agent (b) 100 g of the filler that had been subjected to the hydrolysis treatment and 1 g of hexamethylcyclotrisiloxane were placed in a pressure vessel and reacted for 24 hours at 140° C. Next, 500 mL of ethanol and 100 g of the filler that had been subjected to the surface treatment step with endcapping agent (b), hexamethylcyclotrisiloxane, were placed in a beaker and stirred at room temperature for 30 minutes. This washing step of removing the solvent by filtration under reduced pressure was repeated three times, followed by vacuum drying, to obtain Filler 1.Production Example 2: Production of Filler 2 Filler 2 was produced in the same manner as in Production Example 1, except that the raw material was changed from 8235 UF0.7 grade to GM27884 NF180 grade (barium glass manufactured by SCHOTT, average particle size: 0.18 μm). Production Example 3: Production of Filler 3 Barium glass (manufactured by ESSTECH, 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 on a volume basis using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, model "SALD-2300") and was found to be 2.4 μm. Filler 3 was produced in the same manner as in Production Example 1, except that this filler was used as the raw material instead of 8235 UF0.7 grade. Production Example 4: Production of Filler 4 Silica powder (manufactured by Nichitsu Corporation, quartz, product name: Hi-Silica) was pulverized in a ball mill to obtain pulverized silica powder. The average particle size of the obtained pulverized silica powder was measured on a volume basis using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, model "SALD-2300") and was found to be 2.2 μm. Filler 4 was produced in the same manner as in Production Example 1, except that this filler was used as a raw material instead of 8235 UF0.7 grade. Production Example 5: Production of Filler 5 Filler 5 was produced using the same raw materials and method as in Production Example 1, except that the hydrolysis treatment step was omitted. Production Example 6: Production of Filler 6 Filler 6 was produced using the same raw materials and method as in Production Example 1, except that the hydrochloric acid treatment step was omitted. Production Example 7: Production of Filler 7 After the hydrochloric acid treatment step, filler 7 was produced using 8235 UF0.7 grade, following the surface treatment step with the end capping agent (b) and the surface treatment step with the silane coupling agent (a) in this order in Production Example 1. Production Example 8: Production of Filler 8 Surface-treated silica-zirconia oxide agglomerated filler (product name "SG-SZ200G151CMP8", average particle size of primary particles: 200 nm, average particle size of secondary particles: 5.2 μm, refractive index: 1.51, constituent component: SiO. ２ , ZrO ２ , manufactured by Sukgyung AT Co., Ltd.) was subjected to a hydrolysis treatment step and a surface treatment step with an end-capping agent (b) in the same manner as in Production Example 1 to produce Filler 8.

[0175] [Fillers (C) other than dental surface-treated filler (C-1)] Production Example 9: Production of filler 9 Filler 9 was produced using the same raw materials and method as in Production Example 1, except that the surface treatment step with the silane coupling agent (a) and the hydrolysis treatment step were omitted. Production Example 10: Production of filler 10 Filler 10 was produced by treating 8235 UF0.7 grade only with the surface treatment step with the silane coupling agent (a) of Production Example 1. Production Example 11: Production of filler 11 Filler 11 was produced by treating 8235 UF0.7 grade only with the hydrochloric acid treatment step of Production Example 1 and the surface treatment step with the silane coupling agent (a). Production Example 12: Production of filler 12 Filler 12 was produced by treating GM27884 NF180 grade only with the hydrochloric acid treatment step of Production Example 1 and the surface treatment step with the silane coupling agent (a). Production Example 13: Production of Filler 13 8235 UF0.7 grade was subjected to the hydrochloric acid treatment step, surface treatment step with silane coupling agent (a), and hydrolysis treatment step of Production Example 1, and then treated in the following steps to produce Filler 13. - Surface Treatment Step with Dimethyldimethoxysilane 100 g of the filler obtained in the above step, 5 g of dimethyldimethoxysilane, and 200 mL of a 0.3 mass% acetic acid ethanol solution were placed in a three-necked flask and stirred for 2 hours at room temperature. After removing the solvent by distillation under reduced pressure, the mixture was vacuum dried and heat-treated at 80 °C for 5 hours. Next, 500 mL of ethanol and 100 g of filler (filler surface-treated with dimethyldimethoxysilane) were added to a beaker and stirred at room temperature for 30 minutes. This washing step of removing the solution by vacuum filtration was repeated three times, and then vacuum dried. Production Example 14: Production of Filler 14 8235 UF0.7 grade was subjected to the hydrochloric acid treatment step, surface treatment step with silane coupling agent (a), and hydrolysis treatment step of Production Example 1, and then treated in the following steps to produce Filler 14. Surface treatment step with 1,1,1,3,3,3-hexamethyldisilazane 100 g of the filler obtained in the above step, 200 mL of isopropanol, and 4 g of 1,1,1,3,3,3-hexamethyldisilazane were added to a three-neck flask and reacted at 40°C for 72 hours.5 g of 35% aqueous hydrochloric acid was added to the total mixture obtained after the surface treatment, and a filler (filler surface-treated with 1,1,1,3,3,3-hexamethyldisilazane) was precipitated. The precipitate was filtered through filter paper. Next, 500 mL of distilled water and the precipitate were added back into the beaker, stirred at room temperature for 30 minutes, and the washing process of removing the aqueous solution by vacuum filtration was repeated three times, followed by vacuum drying at 100°C to produce Filler 14. Production Example 15: Production of Filler 15 100 g of OX50 (Nippon Aerosil Co., Ltd., ultrafine silica particle "Aerosil (registered trademark) OX50", average particle size: 0.04 μm), 7 g of 3-methacryloyloxypropyltrimethoxysilane, and 200 mL of 0.3% by mass aqueous acetic acid solution were placed in a three-neck flask and stirred at room temperature for 2 hours. After removing the water by freeze-drying, the mixture was heated at 80°C for 5 hours to produce Filler 15 (silane-treated silica).

[0176] [Polymerization accelerator (D)] DABE: ethyl 4-(N,N-dimethylamino)benzoate

[0177] [Polymerization inhibitor] BHT: 3,5-di-t-butyl-4-hydroxytoluene

[0178] Examples 1-1 to 1-11 and Comparative Examples 1-1 to 1-6 (Preparation of Dental Compositions) Paste-like dental compositions (dental composite resins) were prepared by mixing and kneading the raw materials shown in Tables 1 and 2 in a dark place at room temperature (23°C), and the properties were examined according to the methods of Test Examples 1 and 2 below. In addition, the properties of the fillers prepared according to each Production Example were examined according to the method of Test Example 3. The results are shown in Tables 1 and 2. The surface structure of the surface-treated filler (Filler 9) obtained in Production Example 9 is shown in Figure 1. The surface structure of the surface-treated dental filler (C-1) (Filler 1) obtained in Production Example 1 is shown in Figure 2.

[0179] Test Example 1: Bending Strength Bending strength was evaluated by a bending test in accordance with ISO 4049:2009. Specifically, the procedure is as follows. The prepared paste (dental composition) was filled into a stainless steel mold (2 mm long x 25 mm wide x 2 mm thick), and the top and bottom of the paste (2 mm x 25 mm surfaces) were pressed against glass slides. Next, the paste was cured by irradiating the front and back of the paste through the glass slide with light for 10 seconds at five locations on each side using a dental visible light irradiator "PenCure 2000" (manufactured by Morita Corporation). The resulting cured product was subjected to a bending test using a universal testing machine (Autograph AG-I 100kN, manufactured by Shimadzu Corporation) at a support distance of 20 mm and a crosshead speed of 1 mm / min. The three-point bending strength was measured (n=5), and the average value was calculated.

[0180] Test Example 2: Shear Adhesion Test to Bovine Dentin The labial surface of a bovine mandibular anterior tooth was polished under running water with #80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) to obtain a bovine mandibular anterior tooth with a flat dentin surface exposed. Tape was applied to the bottom of a 15-hole mold (15-hole mold, manufactured by Ultradent, φ35 mm x height 25 mm), and the prepared tooth was fixed onto the tape. Plaster was filled into the mold and left to harden for approximately 30 minutes, obtaining a composite of the bovine mandibular anterior tooth and plaster. The composite was removed from the mold as a sample. The sample was prepared so that the bovine mandibular anterior tooth was exposed on the upper surface of the plaster. The exposed upper surface of a bovine mandibular anterior tooth was polished under running water with #600 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) to a size sufficient to ensure adhesion (φ2.38 mm or more), and then ultrasonically washed with water for 5 minutes.

[0181] A 2.38 mm diameter CR filling mold (Bonding Mold Insert, Ultradent) was attached to a dedicated tool (Bonding Clamp, Ultradent), and the mold was lowered to make close contact with the surface of the sample. The dental composition immediately after preparation in each Example and Comparative Example was thinly filled into the mold hole to a thickness of 1 mm or less, and immediately filled into the mold (up to about 2 / 3 of the mold, approximately 2 mm thick). After leaving for 10 seconds, the dental composition was cured by irradiating with light for 10 seconds using a dental LED light irradiator (Ultradent, product name "VALO") . The sample was removed from the mold and used as a test sample for the adhesion test. The test sample for the adhesion test was then immersed in distilled water in a sample container and left in an incubator set at 37°C for 24 hours, after which it was removed and the adhesive strength was measured. The adhesive strength (shear adhesive strength) was measured by attaching the adhesive test sample to a dedicated holder (Test Base Clamp, Ultradent Corporation), and using a dedicated jig (Crosshead Assembly, Ultradent Corporation) and a universal testing machine (Shimadzu Corporation) at a crosshead speed of 1 mm / min (n = 10), and the average value was calculated. Furthermore, a shear adhesive test on bovine dentin was performed in the same manner as above, except that the dental compositions prepared in each Example and Comparative Example and stored at 60°C for 4 weeks were used instead of the dental compositions prepared immediately after preparation. In Tables 1 and 2, the adhesive test sample prepared immediately after preparation of the paste-like dental composition and the shear adhesive strength measured were designated "initial product," and the adhesive test sample prepared after preparation of the paste-like dental composition and storage at 60°C for 4 weeks and the shear adhesive strength measured were designated "60°C 4-week product."

[0182] Test Example 3 Acid Resistance Test For each of Fillers 1 to 14, 0.5 g of filler was added to a 5% aqueous acetic acid solution, and the mixture was subjected to ultrasonic dispersion for 5 minutes (Branson tabletop ultrasonic cleaner Bransonic (registered trademark) M2800-J, 110W, manufactured by Yamato Scientific Co., Ltd.), and then allowed to stand at room temperature for 6 hours. Next, to remove the filler, the filler was sedimented using a centrifuge (20,000 rpm, 30 minutes, himac CR21GII, manufactured by Eppendorf Himac Technologies Co., Ltd.), and the supernatant was quickly recovered without any time gap. The supernatant was filtered through a membrane filter (pore size: 0.45 μm) to remove impurities, and then elemental analysis was performed using an ICP atomic emission spectrometer (RF power: 1150 W, auxiliary gas flow rate: 0.5 L / min, nebulizer gas flow rate: 0.7 L / min, analytical pump flow rate: 50 rpm, plasma view: axial, low wavelength range: 15 sec, high wavelength range: 10 sec, Thermo Fisher Scientific iCAP6500Duo, manufactured by Thermo Fisher Scientific Inc.) (n = 3), and the average amount of measured metal elements was calculated (unit: mass ppm). The results are shown in Tables 1 and 2. Note that filler 15 was not evaluated for acid resistance, and therefore the acid resistance test results for fillers (C) other than dental surface-treated filler (C-1) in Table 2 represent the results of the acid resistance tests for fillers 9 to 14. It is believed that the lower the amount of metal elements detected in this acid resistance test, the more inhibited the interaction between the acidic component and the filler is, suggesting that the surface of the filler is more densely covered with organic molecules.

[0183]

[0184]

[0185] The results in Table 1 indicate that the dental compositions of the Examples have excellent mechanical strength, with a flexural strength of 94 MPa or more after curing. Furthermore, even after storage at 60°C for four weeks, the dental compositions have excellent storage stability, with a shear bond strength to bovine dentin of 5 MPa or more. On the other hand, as shown in Table 2, among the dental compositions of the Comparative Examples 1-1 to 1-6, which do not contain the dental surface-treated filler (C-1), Comparative Example 1-1 has an insufficient flexural strength of 60 MPa, and Comparative Examples 1-2 to 1-6 have bond strengths to bovine dentin of 1 MPa or less after four weeks of storage at 60°C, confirming poor storage stability under harsh conditions. Filler 11 used in Comparative Example 1-3 and Filler 12 used in Comparative Example 1-4 were treated with hydrochloric acid and surface-treated with a silane coupling agent (a), corresponding to Patent Document 3 (JP 2011-178778 A). Furthermore, the filler 14 used in Comparative Examples 1-6 corresponds to Patent Document 4 (WO 2018 / 074594). Furthermore, in an acid resistance test, the dental surface-treated filler (C-1) of the example had excellent acid resistance of less than 93 ppm, whereas the fillers other than the dental surface-treated filler (C-1) of Comparative Examples 1-2 to 1-6 had elution amounts of metal components of 300 ppm or more. Since there is a correlation between the results of this acid resistance test and the shear adhesion test to bovine dentin, it is believed that the surface of the dental surface-treated filler (C-1) of the present invention is more densely covered with organic molecules, which inhibits the interaction between the polymerizable monomer having an acidic group and the filler, thereby resulting in a dental composition with excellent storage stability even under harsh conditions.

[0186] The dental composition according to the present invention is suitably used in the field of dental treatment as a dental cement, a dental bonding material, a dental composite resin (e.g., a self-adhesive dental composite resin), a dental core construction material, etc.

Claims

1. A composition comprising a polymerizable monomer (A), a polymerization initiator (B), and a filler (C), The filler (C) comprises a surface-treated dental filler (C-1) that has been surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and A dental composition, wherein the amount of metal components eluted from the dental surface-treated filler (C-1) in an acid resistance test is less than 100 ppm.

2. 2. The dental composition according to claim 1, wherein the end-capping agent (b) is a compound having a structure represented by the following formula (1) or (2) and having a boiling point of 180°C or lower: 【Chemistry 1】 【Chemistry 2】 [In the formula, R 1 ~R 6 each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, x represents an integer of 3 to 10, and y represents an integer of 1 to 100.

3. The dental composition according to claim 1, wherein the dental surface-treated filler (C-1) is surface-treated with the silane coupling agent (a) having the polymerizable group and then surface-treated with the end-capping agent (b).

4. 2. The dental composition according to claim 1, wherein the dental surface-treated filler (C-1) is hydrolyzed after being surface-treated with the silane coupling agent (a) having a polymerizable group.

5. 2. The dental composition according to claim 1, wherein the dental surface treatment filler (C-1) comprises a radiopaque filler.

6. The dental composition according to claim 5 , wherein the radiopaque filler is acid-treated.

7. 2. The dental composition according to claim 1, wherein the silane coupling agent (a) having a polymerizable group includes 3-methacryloyloxypropyltrimethoxysilane, 8-(meth)acryloyloxyoctyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, or hydrolysates thereof.

8. The dental composition of claim 1 , wherein the endcapping agent (b) is hexamethylcyclotrisiloxane.

9. The dental composition according to claim 1, wherein the amount of the end-capping agent (b) to be treated on the filler in the surface treatment to obtain the dental surface-treated filler (C-1) is 0.01 to 20 parts by mass per 100 parts by mass of the filler before the surface treatment.

10. 2. The dental composition according to claim 1, wherein the polymerizable monomer (A) comprises a polymerizable monomer (A-1) having an acidic group and a polymerizable monomer (A-2) not having an acidic group.

11. 11. The dental composition according to claim 10, wherein the content of the polymerizable monomer (A-1) having an acidic group is 1 to 40 parts by mass per 100 parts by mass of the polymerizable monomer (A).

12. A self-adhesive dental composite resin comprising the dental composition according to any one of claims 1 to 11.

13. A dental bonding material comprising the dental composition according to any one of claims 1 to 11.

14. A dental cement comprising the dental composition according to any one of claims 1 to 11.

15. A dental composite resin comprising the dental composition according to any one of claims 1 to 11.

16. A dental core construction material comprising the dental composition according to any one of claims 1 to 11.

17. a step of obtaining the dental surface-treated filler (C-1), The method for producing a dental composition according to any one of claims 1 to 11, wherein the steps include a step of surface-treating the filler with a silane coupling agent (a) having a polymerizable group, and a step of surface-treating the filler with an end-capping agent (b).

18. The filler is surface-treated with a silane coupling agent (a) having a polymerizable group and an end-capping agent (b), and A surface-treated dental filler (C-1), wherein the end-capping agent (b) is a compound having a structure represented by the following formula (1) or (2) and having a boiling point of 180°C or lower: 【Transformation 3】 【Chemistry 4】 [In the formula, R 1 ~R 6 each independently represents a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 9 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, x represents an integer of 3 to 10, and y represents an integer of 1 to 100.

19. The dental surface-treating filler (C-1) according to claim 18, wherein the filler comprises an inorganic filler.

20. The dental surface-treated filler (C-1) according to claim 19, wherein the inorganic filler comprises an agglomerated filler.

21. The dental surface-treated filler (C-1) according to any one of claims 18 to 20, which is surface-treated with the silane coupling agent (a) having the polymerizable group and then surface-treated with the end-capping agent (b).

22. The dental surface-treated filler (C-1) according to any one of claims 18 to 20, which is obtained by surface-treating with the silane coupling agent (a) having a polymerizable group and then hydrolyzing the surface-treated filler (C-1).

Images