WO2021107152A1 - Dental composition - Google Patents

Abstract

The purpose of the present invention is to provide a self-etching dental composition exhibiting excellent adhesiveness not only to dentin not etched with phosphoric acid but also to phosphoric acid-etched dentin. The present invention pertains to a dental composition containing: a monomer (A) having an acidic group; a monomer (B) having no acidic group; a photopolymerization initiator (C); and water, wherein the photopolymerization initiator (C) is of an intramolecular cleavage-type, and contains a photopolymerization initiator (C-1) having an absorbance at 420 nm of at least 0.007 when dissolved in water at a concentration of 0.01 wt%, and/or a photopolymerization initiator (C-2) represented by general formula (2). [The meaning of symbols in the formula is omitted.]

Description

Dental composition

The present invention relates to a dental composition used in the field of dentistry. Specifically, the hard tissue (dental substance) of the tooth is bonded to a filling restoration material such as a dental composite resin, a dental compomer, or a dental resin cement, and a metal; porcelain; ceramics; a cured composite resin, etc. The present invention relates to a dental adhesive used for adhering a crown restoration material and a filling restoration material.

To repair dentin (enamel, dentin and cementum) damaged by caries, etc., usually, filling restoration materials such as dental composite resins and dental compomers, metals, porcelain, ceramics and composite resin cured products are used. Crown restoration materials such as are used. However, in general, the filling restoration material and the crown restoration material (both may be collectively referred to as "dental restoration materials" in the present specification) themselves do not have adhesiveness to the dentin. For this reason, various adhesive systems using adhesives have been conventionally used for adhering the dentin and the dental restoration material. As a conventional adhesive system, the surface of the dentin is etched with an acid etching material such as an aqueous phosphoric acid solution, and then a bonding material, which is an adhesive, is applied to the dentin and dentistry. There is a so-called acid etching type (total etching type) bonding system that bonds the restoration material.

On the other hand, there is a so-called self-etching type adhesive system as an adhesive system that does not use an acid etching material. Conventionally, this adhesive system applies a self-etching primer containing an acidic monomer, a hydrophilic monomer, and water to the surface of the dentin, and then bonds the crosslinkable monomer and a polymerization initiator without washing with water. A two-step adhesive system for applying a material was the mainstream, but recently, a one-step using a one-component dental adhesive (one-component bonding material) that has both the functions of a self-etching primer and a bonding material. Adhesive system is widely used.

In addition, even with a self-etching type bonding system, when repairing a part that is highly dependent on enamel adhesion, such as the occlusal surface of a molar tooth or a fracture of the incisal edge of an anterior tooth, or when high adhesion to enamel is required. In some cases, for the purpose of improving the adhesiveness to the enamel, a technique of performing a phosphoric acid etching treatment only on the enamel as a pretreatment, that is, so-called selective etching may be performed. In such a case, dentin is also treated at the boundary between enamel and dentin at the same time, but when phosphoric acid etching treatment, which generally has a strong decalcifying effect, is applied to dentin containing organic substances such as collagen, hydroxy It is known that decalcification of apatite exposes collagen fibers and shrinks the exposed dentin collagen during the washing and drying steps, making it difficult for the polymerizable monomer component contained in the dental adhesive to penetrate. Has been done. Therefore, in the self-etching type dental adhesive, it is difficult to obtain high adhesiveness to the dentin subjected to the phosphoric acid etching treatment, and the self having improved adhesiveness to the dentin after the phosphoric acid etching treatment. Etching type materials are also desired.

The one-component bonding material generally contains an acidic monomer, a hydrophilic monomer, a crosslinkable monomer, etc. as a monomer component, and is usually photocured in the above-mentioned adhesive system. ing. Therefore, a photopolymerization initiator is used in such an adhesive system to impart photopolymerizability. As the photopolymerization initiator, a conventionally well-known camphorquinone / tertiary amine system is the most common. On the other hand, an acylphosphine oxide compound is known as a photopolymerization initiator having excellent photocurability and less discoloration. Among them, 2,4,6-trimethylbenzoyldiphenylphosphine oxide is known to impart excellent adhesiveness to dentin to a polymerizable composition and is widely used (see Non-Patent Document 1).

For example, Patent Documents 1 to 3 also propose a two-step and one-step adhesion system containing an acylphosphine oxide compound. However, even if the amount of the photopolymerization initiator is increased to improve the curability of the composition itself with the aim of improving the curability of the adhesive interface in order to further improve the adhesiveness of such a conventional acylphosphine oxide compound, the dentin There is a limit to the improvement of adhesiveness to dentin, and due to its low solubility in water, it is insufficiently dissolved, dispersed, and diffused in dentin, especially decalcified dentin. According to a later study, there was room for improvement.

Patent Document 4 proposes an aqueous photocurable adhesive composition containing a hydrophilic group-containing radical polymerizable (meth) acrylate-based monomer, a water-soluble photopolymerization initiator, and water as essential components. In No. 5, a dental photopolymerizable composition containing a (meth) acrylate-based monomer, water, and a water-soluble acylphosphine oxide compound as a photopolymerization initiator as a main component has been proposed. However, the compositions of Patent Documents 4 and 5 have insufficient curability with respect to blue LED light, and the monomer component permeating into the dentin is not cured, and the dentin is particularly adhered during phosphoric acid etching. The problem of low dentin has been confirmed, and according to the studies conducted by the present inventors later, it was found that there is room for improvement.

Japanese Unexamined Patent Publication No. 2000-16911 Japanese Unexamined Patent Publication No. 2000-212015 International Publication No. 2010/008077 Japanese Unexamined Patent Publication No. 4-154708 Japanese Unexamined Patent Publication No. 2000-159621

As described above, in the prior art, no dental composition showing excellent adhesiveness not only to the dentin not subjected to the phosphoric acid etching treatment but also to the dentin subjected to the phosphoric acid etching treatment has been found. It was.

Therefore, an object of the present invention is to provide a dental composition that exhibits excellent adhesiveness not only to dentin not subjected to phosphoric acid etching treatment but also to dentin subjected to phosphoric acid etching treatment. ..

As a result of diligent studies, the present inventors have found that the above problems can be solved by using a specific photopolymerization initiator, and have completed the present invention through further studies.

That is, the present invention
[1] The photopolymerization initiator (C) containing a monomer (A) having an acidic group, a monomer (B) having no acidic group, a photopolymerization initiator (C), and water is used. A photopolymerization initiator (C-1) that is an intramolecular cleavage type and has an absorbance at 420 nm of 0.007 or more when dissolved in water at a concentration of 0.01 wt%, and / or the general formula (2). A dental composition comprising a photopolymerization initiator (C-2) represented by.

[In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are independent of each other and have a hydrogen atom and a linear or branched chain having 1 to 4 carbon atoms. An alkyl group, a linear or branched-chain alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH or -COOY ¹ , and at least one of ^{R 1} to R ^{8 is -COOY 1} . , Y ¹ represents an organic cation or an inorganic cation. ]
[2] The dental composition according to [1], wherein the monomer (B) having no acidic group contains a hydrophilic monomer (B-1) having no acidic group;
[3] The dental composition according to [1] or [2], wherein the content of the water is 1 to 500 parts by mass with respect to 100 parts by mass of the total amount of the monomer components;
[4] The dental composition according to any one of [1] to [3], wherein the photopolymerization initiator (C-1) is a compound represented by the general formula (1);

[In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are linear or branched chain alkyl groups or halogen atoms having 1 to 4 carbon atoms independently of each other. X is a linear or branched alkylene group having 1 to 4 carbon atoms, R ¹⁵ is represented by -CH (CH ₃ ) COO (C ₂ H ₄ O) _n CH ₃ , and n is 1 to 1000. Represents an integer of. ]
[5] The dental composition according to [4], wherein X is a methylene group;
[6] The photopolymerization initiator (C) contains the photopolymerization initiator (C-2), and further contains a compound (E-1) represented by the general formula (3) as a polymerization accelerator (E). The dental composition according to any one of [1] to [5].

[In the formula, R ¹⁶ and R ¹⁷ are linear or branched alkyl groups having 1 to 4 carbon atoms independently of each other, and R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ and R ²² are mutually independent. Independently, a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH, -COOH or -COOY ² and at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , where Y ² represents an organic cation or an inorganic cation. ]
[7] R ¹⁶ and R ¹⁷ are methyl or ethyl groups, and at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , and the rest of ^{R 18} to R ^22. The dental composition according to [6], wherein at least one group of the group is -OH or a linear alkoxy group having 1 to 3 carbon atoms.
[8] The photopolymerization initiator (C) contains the photopolymerization initiator (C-2), and at least one group among ^{R 1} to R ^{8 is −COOY 1} , and R ¹ to R ⁸ The dental composition according to any one of [1] to [7], wherein the remaining group is a hydrogen atom or a methyl group;
[9] When R ¹ is a hydrogen atom or a methyl group, R ² is a methyl group or -COOY ¹ , R ³ is a methyl group, and (i) R ² is a methyl group, R ⁴ to If any one of ^{R 8 is -COOY 1} , the other four are hydrogen atoms, and (ii) R ² is -COOY ¹ , then R ⁴ to R ⁸ are all hydrogen atoms, [8 ] The dental composition according to
[10] The dental composition according to any one of [1] to [9], wherein the monomer (A) having an acidic group contains a monomer having a phosphoric acid group;
[11] Further containing a water-insoluble photopolymerization initiator (D), which does not correspond to any of the photopolymerization initiator (C-1) and the photopolymerization initiator (C-2), [1] to [10]. ] The dental composition according to any one of;
[12] The dental composition according to [11], wherein the mass ratio of the photopolymerization initiator (C) to the water-insoluble photopolymerization initiator (D) is 10: 1 to 1:10;
[13] A dental bonding material containing the dental composition according to any one of [1] to [12];
[14] A dental primer containing the dental composition according to any one of [1] to [12];
Including.

According to the present invention, a dental composition showing excellent adhesiveness not only to dentin not subjected to phosphoric acid etching treatment but also to dentin subjected to phosphoric acid etching treatment, and the composition are used. Dental bonding materials and dental primers are provided.

The dental composition of the present invention contains a monomer (A) having an acidic group, a monomer (B) having no acidic group, a photopolymerization initiator (C), and water, and the photopolymerization initiation is carried out. A photopolymerization initiator (C-1) in which the agent (C) is an intramolecular cleavage type and has an absorbance at 420 nm of 0.007 or more when dissolved in water at a concentration of 0.01 wt%, and /. Alternatively, the photopolymerization initiator (C-2) represented by the general formula (2) is contained as an essential component. In the present specification, (meth) acrylic is a general term for methacrylic and acrylic, and the same applies to expressions similar thereto. In this specification, the upper limit value and the lower limit value of the numerical range (content of each component, value calculated from each component, each physical property, etc.) can be appropriately combined.

The reason why the dental composition of the present invention exhibits excellent adhesiveness not only to dentin not subjected to phosphoric acid etching treatment but also to dentin subjected to phosphoric acid etching treatment is not clear, but is as follows. Is estimated to be. That is, it is presumed that the inclusion of the photopolymerization initiator (C) in the dental composition is due to the improvement of the polymerization curability inside the decalcified dentin. In decalcified dentin, collagen fibers are contracted, so that it becomes difficult for monomer components and water to penetrate into the collagen fibers. Among them, in order to enhance the adhesiveness to dentin, it is necessary to surely permeate the photopolymerization initiator component into the decalcified dentin and cure it to form a strong resin impregnated layer. In the photopolymerization initiator used in the conventional dental bonding material, the photopolymerization initiator component does not sufficiently penetrate into the decalcified dentin, and the polymerization rate is insufficient and the fragile resin impregnated layer. I could only get it. Therefore, in order to compensate for the drawbacks and form a sufficient resin-impregnated layer, it is necessary to particularly enhance the polymerization curability of the adhesive interface portion and the inside of the resin-impregnated layer. On the other hand, in the dental composition of the present invention, by using the photopolymerization initiator (C), when it is applied to the decalcified dentin, it is sufficiently introduced into the dentin together with water and a monomer component. The photopolymerization initiator (C) becomes high in concentration, and the polymerization curability inside the adhesive interface and the resin impregnated layer can be selectively enhanced. As a result, the dental composition of the present invention is considered to have high adhesiveness.

Hereinafter, each component used in the dental composition of the present invention will be described.

[Monomer having an acidic group (A)]
The monomer (A) having an acidic group has an acid etching effect and a primer treatment effect, and is a component that gives a decalcifying action and a penetrating action. In addition, the monomer (A) having an acidic group can be polymerized and imparts a curing action. By containing the monomer (A) having an acidic group, the adhesiveness to the dentin and the adhesive durability are improved.

The monomer (A) having an acidic group has at least one acidic group such as a phosphoric acid group, a pyrophosphate group, a thiophosphate group, a phosphonic acid group, a sulfonic acid group and a carboxylic acid group, and (meth). ) Examples thereof include a monomer having at least one polymerizable group such as an acryloyl group, a vinyl group and a styrene group. From the viewpoint of dentin adhesion, a phosphoric acid group-containing monomer is preferable. Specific examples of the monomer (A) having an acidic group will be given below.

Examples of the phosphate group-containing monomer include 2- (meth) acryloyloxyethyl dihydrogen phosphate, 3- (meth) acryloyloxypropyl dihydrogen phosphate, 4- (meth) acryloyloxybutyl dihydrogen phosphate, and 5- (meth). ) Acryloyloxypentyl dihydrogen phosphate, 6- (meth) acryloyl oxyhexyl dihydrogen phosphate, 7- (meth) acryloyl oxyheptyl dihydrogen phosphate, 8- (meth) acryloyl oxyoctyl dihydrogen phosphate, 9- (meth) acryloyl Oxynonyldihydrogenphosphate, 10- (meth) acryloyloxydecyldihydrogenphosphate, 11- (meth) acryloyloxyundecyldihydrogenphosphate, 12- (meth) acryloyloxidedecyldihydrogenphosphate, 16- (meth) acryloyloxy Hexadecyldihydrogen phosphate, 20- (meth) acryloyloxyicosildihydrogenphosphate, bis [2- (meth) acryloyloxyethyl] hydrogen phosphate, bis [4- (meth) acryloyloxybutyl] hydrogen phosphate, bis [6- (Meta) acryloyloxyhexyl] hydrogen phosphate, bis [8- (meth) acryloyloxyoctyl] hydrogen phosphate, bis [9- (meth) acryloyloxynonyl] hydrogen phosphate, bis [10- (meth) ) Acryloyloxydecyl] Hydrogenphosphate, 1,3-di (meth) acryloyloxypropyldihydrogenphosphate, 2- (meth) acryloyloxyethylphenylhydrogenphosphate, 2- (meth) acryloyloxyethyl-2-bromoethyl Examples thereof include hydrogen phosphate, bis [2- (meth) acryloyloxy- (1-hydroxymethyl) ethyl] hydrogen phosphate and their acid salts, alkali metal salts, and ammonium salts.

Examples of the pyrophosphate group-containing monomer include bis pyrophosphate [2- (meth) acryloyloxyethyl], bis pyrophosphate [4- (meth) acryloyloxybutyl], and bis pyrophosphate [6- (meth) acryloyloxyhexyl]. ], Bispyrophosphate [8- (meth) acryloyloxyoctyl], bispyrophosphate [10- (meth) acryloyloxydecyl] and their acid salts, alkali metal salts, and ammonium salts.

Examples of the thiophosphate group-containing monomer include 2- (meth) acryloyloxyethyl dihydrogenthiophosphate, 3- (meth) acryloyloxypropyldihydrogenthiophosphate, 4- (meth) acryloyloxybutyldihydrogenthiophosphate, and 5, -(Meta) Acryloyloxypentyl dihydrogenthiophosphate, 6- (Meta) Acryloyloxyhexyl dihydrogenthiophosphate, 7- (Meta) Acryloyloxyheptyl dihydrogenthiophosphate, 8- (Meta) Acryloyloxyoctyl dihydrogenthiophosphate , 9- (meth) acryloyloxynonyl dihydrogenthiophosphate, 10- (meth) acryloyloxydecyldihydrogenthiophosphate, 11- (meth) acryloyloxyundecyldihydrogenthiophosphate, 12- (meth) acryloyloxide decyldihydro Examples thereof include gentiophosphate, 16- (meth) acryloyloxyhexadecyldihydrogenthiophosphate, 20- (meth) acryloyloxyicosyldihydrogenthiophosphate and their acid salts, alkali metal salts and ammonium salts.

Examples of the phosphonic acid group-containing monomer include 2- (meth) acryloyloxyethylphenylphosphonate, 5- (meth) acryloyloxypentyl-3-phosphonopropionate, and 6- (meth) acryloyloxyhexyl-3-phospho. Nopropionate, 10- (meth) acryloyloxydecyl-3-phosphonopropionate, 6- (meth) acryloyloxyhexyl-3-phosphonoacetate, 10- (meth) acryloyloxydecyl-3-phosphono Examples thereof include acetates and their acid salts, alkali metal salts and ammonium salts.

Examples of the sulfonic acid group-containing monomer include 2- (meth) acrylamide-2-methylpropanesulfonic acid, styrenesulfonic acid, and 2-sulfoethyl (meth) acrylate.

Examples of the carboxylic acid group-containing monomer include a monomer having one carboxy group in the molecule and a monomer having a plurality of carboxy groups in the molecule.

Examples of the monomer having one carboxy group in the molecule include (meth) acrylic acid, N- (meth) acryloyl glycine, N- (meth) acryloyl aspartic acid, O- (meth) acryloyl tyrosine, and N- (meth). ) Acryloyl tyrosine, N- (meth) acryloylphenylalanine, N- (meth) acryloyl-p-aminobenzoic acid, N- (meth) acryloyl-o-aminobenzoic acid, p-vinylbenzoic acid, 2- (meth) acryloyl Oxybenzoic acid, 3- (meth) acryloyloxybenzoic acid, 4- (meth) acryloyloxybenzoic acid, N- (meth) acryloyl-5-aminosalicylic acid, N- (meth) acryloyl-4-aminosalicylic acid, 2- Examples thereof include (meth) acryloyloxyethyl hydrogen succinate, 2- (meth) acryloyloxyethyl hydrogenphthalate, 2- (meth) acryloyloxyethyl hydrogenmalate and acid halides thereof.

Examples of the monomer having a plurality of carboxy groups in the molecule include 6- (meth) acryloyloxyhexane-1,1-dicarboxylic acid and 9- (meth) acryloyloxynonan-1,1-dicarboxylic acid, 10- ( Meta) Acryloyloxydecane-1,1-dicarboxylic acid, 11- (meth) acryloyloxyundecane-1,1-dicarboxylic acid, 12- (meth) acryloyloxidedecane-1,1-dicarboxylic acid, 13- (meth) Acryloyloxytridecane-1,1-dicarboxylic acid, 4- (meth) acryloyloxyethyl trimerite, 4- (meth) acryloyloxyethyl trimerite anhydride, 4- (meth) acryloyloxybutyl trimerite, 4- (Meta) acryloyloxyhexyl trimerite, 4- (meth) acryloyloxydecyl trimerite, 2- (meth) acryloyloxyethyl-3'-(meth) acryloyloxy-2'-(3,4-) Dicarboxybenzoyloxy) propyl succinate and acid anhydrides or acid halides thereof.

Among these monomers having an acidic group (A), a phosphoric acid group or a pyrophosphate group-containing (meth) acrylic monomer is preferable because it exhibits better adhesiveness to the dentin. A (meth) acrylic monomer containing a phosphoric acid group is preferable. Among them, divalent phosphorus having an alkyl group or an alkylene group having 6 to 20 carbon atoms as a main chain in the molecule in that it exhibits high decalcification and high adhesiveness in the absence of an organic solvent. Acid group-containing (meth) acrylic monomers are more preferable, and they contain a divalent phosphate group having an alkylene group having 8 to 12 carbon atoms as the main chain in the molecule such as 10-methacryloyloxydecyldihydrogen phosphate (10-methacryloyloxydecyldihydrogen phosphate). Meta) Acrylic monomers are more preferred.

As the monomer (A) having an acidic group, one type may be used alone, or two or more types may be used in combination. Adhesiveness may decrease when the content of the monomer (A) having an acidic group is too high or too low. Therefore, the content of the monomer (A) having an acidic group is preferably in the range of 1 to 70 parts by mass, preferably in the range of 3 to 50 parts by mass, based on 100 parts by mass of the total amount of the monomer components in the dental composition. Is more preferable, and the range of 5 to 25 parts by mass is further preferable.

[Monomer having no acidic group (B)]
The monomer (B) having no acidic group can be classified into a hydrophilic monomer (B-1) having no acidic group and a hydrophobic monomer (B-2) having no acidic group. As the monomer (B) having no acidic group, either a hydrophilic monomer (B-1) having no acidic group or a hydrophobic monomer (B-2) having no acidic group is used. However, both may be used in combination. In one preferred embodiment, it contains a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), and water, and has no acidic group. Examples thereof include dental compositions in which the metric (B) contains a hydrophilic monomer (B-1) having no acidic group and a hydrophobic monomer (B-2) having no acidic group.

-Hydrophilic monomer having no acidic group (B-1)
The dental composition of the present invention further comprises a hydrophilic monomer (B-1) having no acidic group (hereinafter, may be simply referred to as "hydrophilic monomer (B-1)"). Is preferable. The hydrophilic monomer (B-1) promotes the penetration of the components of the dental composition into the dentin, and also permeates the dentin itself and adheres to the organic component (collagen) in the dentin. As the hydrophilic monomer (B-1), a radical monomer having no acidic group and having a polymerizable group is preferable, and the polymerizable group is (meth) acrylamide from the viewpoint of easy radical polymerization. Radicals and / or (meth) acrylamide groups are preferred. The hydrophilic monomer (B-1) in the present invention means a monomer having a solubility in water at 25 ° C. of 10% by mass or more, preferably having a solubility of 30% by mass or more, and is arbitrary at 25 ° C. Those that can be dissolved in water in proportion are more preferable. The hydrophilic monomer (B-1) preferably has a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxyproprene group, or an amide group, and is preferably, for example, 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 ) Hydrophilic monofunctional (meth) acrylate-based monomers such as ethyltrimethylammonium chloride, polyethylene glycol di (meth) acrylate (having 9 or more oxyethylene groups); N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N, N-bis (2-hydroxyethyl) (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, diacetone (meth) acrylamide, 4 -(Meta) acryloylmorpholine, N-trihydroxymethyl-N-methyl (meth) acrylamide, N, N-dimethylacrylamide and monofunctional (meth) acrylamide-based monomers such as N, N-diethylacrylamide are mentioned. Be done.

Among these hydrophilic monomers (B-1), 2-hydroxyethyl (meth) acrylate, 2,3-dihydroxypropyl (meth) acrylate, diacetone (meth) acrylamide and hydrophilic are used from the viewpoint of adhesion to dentin. A monofunctional (meth) acrylamide-based monomer is preferable, and 2-hydroxyethyl (meth) acrylate, N, N-dimethylacrylamide and N, N-diethylacrylamide are more preferable. As the hydrophilic monomer (B-1), one type may be used alone, or two or more types may be used in combination.

If the content of the hydrophilic monomer (B-1) in the present invention is too small, the effect of improving the adhesiveness may not be sufficiently obtained, and if it is too large, the mechanical strength may decrease. is there. Therefore, the content of the hydrophilic monomer (B-1) is preferably in the range of 5 to 70 parts by mass, preferably 7 to 60 parts by mass, based on 100 parts by mass of the total amount of the monomer components in the dental composition. Is more preferable, and the range of 10 to 50 parts by mass is further preferable.

-Hydrophobic monomer having no acidic group (B-2)
The hydrophobic monomer (B-2) having no acidic group (hereinafter, may be simply referred to as “hydrophobic monomer (B-2)”) is the mechanical strength and handling of the dental composition. Improve sex etc. A radical monomer having no acidic group and having a polymerizable group is preferable, and the polymerizable group is preferably a (meth) acryloyloxy group and / or a (meth) acrylamide group from the viewpoint of easy radical polymerization. The hydrophobic monomer (B-2) in the present invention means a monomer having a solubility in water at 25 ° C. of less than 10% by mass, and for example, an aromatic compound-based bifunctional monomer or an aliphatic compound. Examples thereof include crosslinkable monomers such as bifunctional monomers of the system and monomers having trifunctionality or higher.

Examples of the aromatic compound-based bifunctional monomer include 2,2-bis ((meth) acryloyloxyphenyl) propane and 2,2-bis [4- (3- (meth) acryloyloxy-2-). Hydroxypropoxy) phenyl] propane, 2,2-bis (4- (meth) acryloyloxyethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxypolyethoxyphenyl) propane, 2,2-bis ( 4- (Meta) acryloyloxydiethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytetraethoxyphenyl) propane , 2,2-Bis (4- (meth) acryloyloxypentaethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxydipropoxyphenyl) propane, 2- (4- (meth) acryloyloxydi) Ethoxyphenyl) -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- (3-methacryloyloxy-2-hydroxypropoxy) phenyl] propane (commonly known as "Bis-GMA"), 2,2-bis (4- (meth) acryloyloxyethoxyphenyl) ) Propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (with an average additional molar number of ethoxy groups of 2.6, commonly known as "D-2.6E"), 2,2-bis (4) -(Meta) acryloyloxydiethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxytetraethoxyphenyl) propane, 2,2-Bis (4- (meth) acryloyloxypentaethoxyphenyl) propane is preferred.

Examples of the aliphatic compound-based bifunctional monomer include glycerol di (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, and propylene glycol di. (Meta) 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- Hexadiol 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, N-methacryloyloxypropylamide and the like can be mentioned. Among these, triethylene glycol diacrylate, triethylene glycol dimethacrylate (commonly known as "3G"), neopentyl glycol di (meth) acrylate, 1,2-bis (3-methacryloyloxy-2-hydroxypropoxy) ethane, 2 , 2,4-trimethylhexamethylene bis (2-carbamoyloxyethyl) dimethacrylate (commonly known as "UDM"), 1,10-decanediol dimethacrylate (commonly known as "DD"), 2,2,4-trimethylhexamethylene bis (2-Carbomoyloxyethyl) dimethacrylate and N-methacryloyloxyethyl acrylamide (commonly known as "MAEA") are preferable.

Examples of the trifunctional or higher monomer include trimethylolpropane tri (meth) acrylate, trimethylolethanetri (meth) acrylate, trimethylolmethane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol. Tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, N, N- (2,2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propan-1,3-diol] tetra (meth) Acrylate, 1,7-diacryloyloxy-2,2,6,6-tetra (meth) acryloyloxymethyl-4-oxaheptan and the like can be mentioned. Among these, N, N- (2,2,4-trimethylhexamethylene) bis [2- (aminocarboxy) propane-1,3-diol] tetramethacrylate is preferable.

Among the above hydrophobic monomers (B-2), aromatic compound-based bifunctional monomers and aliphatic compound-based bifunctional monomers are selected from the viewpoint of mechanical strength and handleability. It is preferably used. As the aromatic compound-based bifunctional monomer, Bis-GMA and D-2.6E are preferable. Examples of the aliphatic compound-based bifunctional monomer include 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.

Among the above hydrophobic monomers (B-2), Bis-GMA, D-2.6E, 3G, UDMA, DD, MAEA from the viewpoint of initial adhesive strength to tooth substance, adhesive durability, and mechanical strength. Is more preferable, and Bis-GMA, 3G, UDMA, and MAEA are even more preferable.

As the hydrophobic monomer (B-2), one type may be used alone, or two or more types may be used in combination. When the content of the hydrophobic monomer (B-2) is excessive, the permeability of the dental composition to the dentin may decrease and the adhesive strength may decrease, and when the content is too small. May not have a sufficient effect of improving mechanical strength. Therefore, the hydrophobic monomer (B-2) is preferably in the range of 5 to 80 parts by mass, preferably in the range of 10 to 70 parts by mass, based on 100 parts by mass of the total amount of the monomer components in the dental composition. More preferably, the range of 12 to 60 parts by mass is further preferable.

[Photopolymerization Initiator (C)]
The dental composition of the present invention is an intramolecular cleavage type as a photopolymerization initiator (C) and has an absorbance at 420 nm of 0.007 or more when dissolved in water at a concentration of 0.01 wt%. It contains a photopolymerization initiator (C-1) and / or a photopolymerization initiator (C-2) represented by the general formula (2). The dental composition of the present invention can achieve high adhesiveness by containing such a photopolymerization initiator (C) in combination with other monomer components.

First, a photopolymerization initiator (C-1) which is an intramolecular cleavage type and has an absorbance at 420 nm of 0.007 or more when dissolved in water at a concentration of 0.01 wt% (hereinafter, simply "photopolymerization"). Initiator (C-1) ”) will be described.

The photopolymerization initiator (C-1) is an intracellular cleavage type. The intramolecular cleavage type in the present specification is a type in which a photopolymerization initiator absorbs light and then generates radicals by intramolecular cleavage. The type that generates radicals by exchanging hydrogen or electrons within or between two molecules is called a hydrogen extraction type or an electron donation type.

The photopolymerization initiator (C-1) has an absorbance at 420 nm (hereinafter, may be simply referred to as “absorbance at 420 nm”) of 0.007 or more when dissolved in water at a concentration of 0.01 wt%. Yes, 0.010 or more is preferable, 0.012 or more is more preferable, and 0.015 or more is further preferable. The absorbance was measured by a spectrophotometer and passed through a glass or quartz measuring cell containing a solution of a photopolymerization initiator (C-1) dissolved in water at a concentration of 0.01 wt%. It is expressed as the ratio of the light intensity to the intensity of the light passing through the measuring cell filled only with water. If the photopolymerization initiator is insoluble in water at a concentration of 0.01 wt% and a solid content remains, such a photopolymerization initiator is not included in the photopolymerization initiator (C-1). Further, when it can be visually determined that the solution becomes cloudy, the absorbance at 420 nm increases as the absorbance at the baseline other than the absorption wavelength of the photopolymerization initiator increases. Such a photopolymerization initiator Is not included in the photopolymerization initiator (C-1). Since the photopolymerization initiator (C-1) has a high absorbance at 420 nm, it exhibits high curability when the dental composition is polymerized by a blue LED light irradiator. As the photopolymerization initiator (C-1), one type may be used alone, or two or more types may be used in combination.

As the photopolymerization initiator (C-1), a compound represented by the following general formula (1) (hereinafter, may be simply referred to as “compound (C-1a)”) is preferable. By having the structure of the following general formula (1), it not only sufficiently penetrates into the dentin together with water and the monomer component, but also becomes a relatively large conjugated system (structure having a conjugated double bond) in the molecule. It is considered that this causes the absorption peak wavelength to shift, and the polymerization curability inside the bonding interface and the resin impregnated layer can be selectively enhanced while being an intramolecular cleavage type.

[In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are linear or branched chain alkyl groups or halogen atoms having 1 to 4 carbon atoms independently of each other. X is a linear or branched alkylene group having 1 to 4 carbon atoms, R ¹⁵ is represented by -CH (CH ₃ ) COO (C ₂ H ₄ O) _n CH ₃ , and n is 1 to 1000. Represents an integer of. ]

The alkyl groups of R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , and R ¹⁴ are not particularly limited as long as they are linear or branched chains having 1 to 4 carbon atoms, and the methyl group, Ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, 2-methylpropyl group, tert-butyl group and the like can be mentioned. As ^{the alkyl group of R 9} , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , and R ^14, a linear alkyl group having 1 to 3 carbon atoms is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is preferable. Is even more preferable. Examples of the alkylene group of X include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an n-butylene group and the like. As the alkylene group of X, a linear alkylene group having 1 to 3 carbon atoms is preferable, a methylene group or an ethylene group is more preferable, and a methylene group is further preferable. As a preferred embodiment, comprises a photopolymerization initiator (C) is a compound ^(C-1a), n of ^{R 15} can be mentioned dental composition is 3 to 100.

Among these, ^{compounds in which R 9} , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are all methyl groups are particularly preferable from the viewpoint of storage stability and color stability in the dental composition. .. On the other hand, as R ^15, from the viewpoint of adhesiveness increases by water-soluble is increased, n represents preferably 1 or more, more preferably 2 or more, more preferably 3 or more, particularly preferably 4 or more, while the If n is too large, the molecular weight becomes too large and the curability deteriorates. Therefore, 1000 or less is preferable, 100 or less is more preferable, 75 or less is further preferable, and 50 or less is particularly preferable.

The compound (C-1a) having such a structure can be synthesized according to a known method. For example, Chem. Commun. , 2018, 54 (8), 920-923 and the like. Further, the numerical value of n is determined by the molecular weight of polyethylene glycol methyl ether methacrylate, which is a raw material. As an example of the compound, for example, a compound synthesized from polyethylene glycol methyl ether methacrylate of n = 9, polyethylene glycol methyl ether methacrylate of n = 23, etc. Examples thereof include compounds synthesized from, and compounds synthesized from polyethylene glycol methyl ether methacrylate having a molecular weight of 950.

Specific examples of the compound (C-1a) are not particularly limited as long as the effects of the present invention are exhibited, and examples thereof include those shown below.

Next, the photopolymerization initiator (C-2) represented by the general formula (2) may be simply referred to as "compound (C-2a)" or "photopolymerization initiator (C-2)". .) Will be described. In the dental composition of the present invention, in the embodiment in which the photopolymerization initiator (C) contains the compound (C-2a), the polymerization accelerator (E) is represented by the general formula (3) described later. It is preferable to use the compound (E-1) in combination from the viewpoint of exhibiting high initial adhesive strength and adhesive durability to the dentin. As the photopolymerization initiator (C-2), one type may be used alone, or two or more types may be used in combination.

[In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are independent of each other and have a hydrogen atom and a linear or branched chain having 1 to 4 carbon atoms. An alkyl group, a linear or branched-chain alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH or -COOY ¹ , and at least one of ^{R 1} to R ^{8 is -COOY 1} . , Y ¹ represents an organic cation or an inorganic cation. ]

The alkyl group of R ¹ to R ⁸ is not particularly limited as long as it has a linear or branched chain having 1 to 4 carbon atoms, and examples thereof include the same alkyl groups as those of R ⁹ to R ¹⁴ . As ^{the alkyl group of R 1} to R ^8, a linear alkyl group having 1 to 3 carbon atoms is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is further preferable. The alkoxy group of R ¹ to R ⁸ is not particularly limited as long as it has a linear or branched chain having 1 to 4 carbon atoms, and is a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, or n. -Butoxy group, sec-butoxy group, tert-butoxy group and the like can be mentioned. As the alkoxy group, a linear alkoxy group having 1 to 3 carbon atoms is preferable, a methoxy group or an ethoxy group is more preferable, and a methoxy group is further preferable.

As Y ¹ , alkali metal ion, alkaline earth metal ion, magnesium ion, pyridinium ion (the pyridine ring may have a substituent), or HN ⁺ R ²³ R ²⁴ R ²⁵ (in the formula, R ^23). , R ²⁴ , and R ²⁵ independently represent an organic group or a hydrogen atom), preferably ammonium ions.

Examples of the alkali metal ion include lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion. Examples of the alkaline earth metal ion include calcium ion, strontium ion, barium ion, and radium ion. When Y ¹ is a pyridinium ion, the substituent of the pyridine ring includes a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a carboxy group, and a linear or branched chain having 2 to 6 carbon atoms. Examples thereof include an acyl group, a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkoxy group having 1 to 6 carbon atoms. Examples of the ^{ammonium ion represented by HN +} R ²³ R ²⁴ R ²⁵ include those derived from various amines. Examples of the amines include ammonia, trimethylamine, diethylamine, dimethylaniline, ethylenediamine, triethanolamine, N, N-dimethylaminomethacrylate, 4- (N, N-dimethylamino) benzoic acid and its alkyl ester, 4-( N, N-diethylamino) benzoic acid and its alkyl ester, N, N-bis (2-hydroxyethyl) -p-toluidine and the like can be mentioned. Examples of the organic group of R ²³ , R ²⁴ , and R ²⁵ include those similar to the substituent of the pyridine ring (excluding the halogen atom). Among these, as Y ¹ , lithium ion, sodium ion, potassium ion, calcium ion, magnesium ion, ^{ammonium ion represented by HN +} R ²³ R ²⁴ R ²⁵ are preferable, and lithium ion, sodium ion, potassium ion, and so on. Calcium ion and magnesium ion are more preferable, and lithium ion and sodium ion are further preferable. For example, ^{Y 1} is a divalent ion (e.g., calcium ions), the "- COOY ^1" is represented as "-COOCa _1/2". In other words, when Y ¹ is a divalent ion, the compound (C-2a) represented by the general formula (2) forms a dimer.

The compound (C-2a) is preferably a compound in which at least one group of ^{R 1} to R ^{8 is -COOY 1} ; at least one group of ^{R 1} to R ^{8 is -COOY 1} . and ^R 1 compound remaining groups are hydrogen atom or a methyl group ~ ^{R 8} are more ^preferred; a -COOY ¹ is at least one group of R 1 ~ ^{R 8,} and the remaining ^R 1 ~ ^{R 8} A compound in which the group of is a hydrogen atom or a methyl group and the number of methyl groups is 3 or less is more preferable; R ¹ is a hydrogen atom or a methyl group, R ² is a methyl group or -COOY ¹ , and R ^{When 3} is a methyl group and (i) R ² is a methyl group, any one of ^{R 4} to R ^{8 is -COOY 1} , the other four are hydrogen atoms, and (ii) R ² When is −COOY ¹ , a ^{compound in which all of R 4} to R ⁸ are hydrogen atoms is particularly preferable. Among these, R ¹ is a hydrogen atom or a methyl group, R ² and R ³ are methyl groups, R ⁴ , R ⁵ , R ⁶ and R ⁷ are all hydrogen atoms, and R ⁸ is a COOY. ^The compound of 1 is most preferable from the viewpoint of adhesion to the dentin.

The compound (C-2a) having such a structure can be synthesized according to a known method.

Specific examples of the compound (C-2a) are not particularly limited, but the following can be mentioned.

The content of the photopolymerization initiator (C) is 0.01 to 20% by mass with respect to 100 parts by mass of the total amount of the monomer components in the dental composition from the viewpoint of curability of the obtained dental composition. Parts are preferable, and from the viewpoint of exhibiting high adhesiveness, 0.05 to 10 parts by mass is more preferable, and 0.1 to 5 parts by mass is further preferable. When the content of the photopolymerization initiator (C) is less than 0.01 parts by mass, the polymerization at the bonding interface does not proceed sufficiently, which may lead to a decrease in the bonding strength. On the other hand, if the content of the photopolymerization initiator (C) exceeds 20 parts by mass, or if the polymerization performance of the photopolymerization initiator (C) is low, sufficient adhesive strength may not be obtained.

[Water-insoluble photopolymerization initiator (D) that does not fall under either of the photopolymerization initiators (C-1) and (C-2)]
The dental composition of the present invention does not fall under any of the photopolymerization initiators (C-1) and (C-2) from the viewpoint of curability, and is a water-insoluble photopolymerization initiator (D) (hereinafter referred to as). , It may be referred to simply as "water-insoluble photopolymerization initiator (D)"). The water-insoluble photopolymerization initiator (D) used in the present invention is a photopolymerization initiator having a solubility in water at 25 ° C. of less than 10 g / L, and is a known photopolymerization initiator that is water-insoluble. Can be used. The water-insoluble photopolymerization initiator (D) may be used alone or in combination of two or more.

Examples of the water-insoluble photopolymerization initiator (D) include (bis) acylphosphine oxides, thioxanthones, ketals, α-diketones, coumarin compounds, anthraquinones, benzoin alkyl ether compounds, α-aminoketone compounds and the like. Can be mentioned.

Among the (bis) acylphosphine oxides, the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TMDPO), 2,6-dimethoxybenzoyldiphenylphosphine oxide, and 2,6-dichlorobenzoyldiphenyl. Phosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, benzoyldi (2,6- Dimethylphenyl) phosphonate and the like. Examples of bisacylphosphine oxides include bis (2,6-dichlorobenzoyl) phenylphosphine oxide, bis (2,6-dichlorobenzoyl) -2,5-dimethylphenylphosphine oxide, and 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, bis (2,5,6-trimethyl) Benzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned.

Examples of the thioxanthones include thioxanthone and 2-chlorothioxanthene-9-one.

Examples of the ketals include benzyldimethyl ketal and benzyldiethyl ketal.

Examples of the α-diketones include diacetyl, benzyl, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4'-oxybenzyl, acenaphthenquinone and the like. Can be mentioned. Among these, dl-camphorquinone is particularly preferable from the viewpoint of having a maximum absorption wavelength in the visible light region.

Examples of the coumarin compound include 3,3'-carbonylbis (7-diethylamino kumarin), 3- (4-methoxybenzoyl) coumarin, 3-thienoyl coumarin, 3-benzoyl-5,7-dimethoxy kumarin, 3 -Benzoyl-7-methoxykumarin, 3-benzoyl-6-methoxykumarin, 3-benzoyl-8-methoxykumarin, 3-benzoyl kumarin, 7-methoxy-3- (p-nitrobenzoyl) kumarin, 3- (p-) Nitrobenzoyl) coumarin, 3,5-carbonylbis (7-methoxycumarin), 3-benzoyl-6-bromokumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocumarin, 3-benzoylbenzo [F] Kumarin, 3-carboxykumarin, 3-carboxy-7-methoxykumarin, 3-ethoxycarbonyl-6-methoxykumarin, 3-ethoxycarbonyl-8-methoxykumarin, 3-acetylbenzo [f] kumarin, 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-ethoxycinnamoyle) -7-methoxycoumarin , 3- (4-Dimethylaminocinnamoyle) coumarin, 3- (4-diphenylaminocinnamoyle) coumarin, 3-[(3-dimethylbenzothiazole-2-iriden) acetyl] coumarin, 3-[(1-methylnaphthoyl) [1,2-d] thiazole-2-iriden) acetyl] coumarin, 3,3'-carbonylbis (6-methoxycumarin), 3,3'-carbonylbis (7-acetoxycmarin), 3,3'- Carbonylbis (7-dimethylaminocoumarin), 3- (2-benzothiazolyl) -7- (diethylamino) coumarin, 3- (2-benzothiazolyl) -7- (dibutylamino) coumarin, 3- (2-benzoimidazolyl) -7 -(Diethylamino) coumarin, 3- (2-benzothiazolyl) -7- (dioctylamino) coumarin, 3-acetyl-7- (dimethylamino) coumarin, 3,3'-carbonylbis (7-dibutylaminocoumarin), 3 , 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] quinolidine-11-one, 10- (2-benzothiazolyl)- 2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H, 11H- [1] benzopyrano [6,7,8-ij] quinolidine-11-one, etc. Examples thereof include compounds described in Japanese Patent Application Laid-Open No. -3109 and Japanese Patent Application Laid-Open No. 10-245525.

Among the above-mentioned coumarin compounds, 3,3'-carbonylbis (7-diethylaminocoumarin) and 3,3'-carbonylbis (7-dibutylaminocoumarin) are particularly preferable.

Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benz anthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, 1-hydroxyanthraquinone and the like. ..

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

Examples of the α-aminoketone compound include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one.

Among these water-insoluble photopolymerization initiators (D), it is preferable to use at least one selected from the group consisting of (bis) acylphosphine oxides, α-diketones, and coumarin compounds. As a result, a dental composition having excellent photocurability in the visible and near-ultraviolet regions and exhibiting sufficient photocurability using any light source such as a halogen lamp, a light emitting diode (LED), or a xenon lamp can be obtained.

The content of the water-insoluble photopolymerization initiator (D) is not particularly limited, but from the viewpoint of curability of the dental composition and the like, it is 0 with respect to 100 parts by mass of the total amount of the monomers in the dental composition. The range of 0.01 to 10 parts by mass is preferable, the range of 0.05 to 7 parts by mass is more preferable, and the range of 0.1 to 5 parts by mass is further preferable. If the content of the water-insoluble photopolymerization initiator (D) exceeds 10 parts by mass, sufficient adhesive strength may not be obtained if the polymerization performance of the photopolymerization initiator itself is low, and further. May lead to precipitation from the dental composition.

The dental composition of the present invention has a mass ratio of the photopolymerization initiator (C) to the water-insoluble photopolymerization initiator (D) of 10: 1 to 1:10 from the viewpoint of curability and the like. Is preferable, and it is more preferably 7: 1 to 1: 7, and even more preferably 5: 1 to 1: 5.

[Water-soluble photopolymerization initiator (C') that does not fall under either photopolymerization initiator (C-1) or (C-2)]
From the viewpoint of curability, the dental composition of the present invention does not fall under any of the photopolymerization initiators (C-1) and (C-2), and is a water-soluble photopolymerization initiator (hereinafter, simply "water-soluble"). It may be further referred to as "sexual photopolymerization initiator (C')"). The water-soluble photopolymerization initiator (C') used in the present invention is a photopolymerization initiator having a solubility in water at 25 ° C. of 10 g / L or more, and a known water-soluble photopolymerization initiator is used. can do. As the water-soluble photopolymerization initiator (C'), one type may be used alone, or two or more types may be used in combination. In certain preferred embodiments, a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), water, and a water-insoluble photopolymerization initiator ( D) is contained, and the photopolymerization initiator (C) contains a photopolymerization initiator (C-1) and / or a photopolymerization initiator (C-2), and is a water-soluble photopolymerization initiator (C'. ) Is not included in the dental composition. Other preferred embodiments include a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), and water to initiate the photopolymerization. Examples of the agent (C) include a dental composition comprising a photopolymerization initiator (C-1) and / or a photopolymerization initiator (C-2).

Examples of the water-soluble photopolymerization initiator (C') include water-soluble acylphosphine oxides, water-soluble thioxanthones, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-. 1-Propane-1-one with (poly) ethylene glycol chain introduced into the hydroxyl group, 1-hydroxycyclohexylphenyl ketone with (poly) ethylene glycol chain introduced into the hydroxyl group and / or phenyl group, 1-hydroxycyclohexyl _{-OCH 2} COO ^- Na ⁺ introduced into the phenyl group of phenyl ketone, (poly) ethylene glycol chain introduced into the hydroxyl group and / or phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one. Α-Hydroxyalkylacetophenones such as those obtained by introducing _{-OCH 2} COO ^- Na ⁺ into the phenyl group of 2-hydroxy-2-methyl-1-phenylpropan-1-one; 2-methyl-1 [4] -(Methylthio) Phenyl] -2-morpholinopropane-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) Butanone-1 and other α-aminoalkylphenones amino groups are quaternary. Examples include ammonium chloride.

The water-soluble acylphosphine oxides are represented by the following general formula (4).

[In the formula, R ²⁶ , R ²⁷ , and R ²⁸ are linear or branched alkyl groups or halogen atoms having 1 to 4 carbon atoms independently of each other, and M is a hydrogen ion, an alkali metal ion, and the like. Alkaline earth metal ion, magnesium ion, pyridinium ion (the pyridine ring may have a substituent), or HN ⁺ R ²³ R ²⁴ R ²⁵ (in the formula, R ²³ , R ²⁴ , and R ²⁵ are each other. Independently, it is an ammonium ion represented by (organic group or hydrogen atom), and n represents 1 or 2. ]

The alkyl groups of R ²⁶ , R ²⁷ , and R ²⁸ are not particularly limited as long as they are linear or branched chains having 1 to 4 carbon atoms, and are methyl group, ethyl group, n-propyl group, and isopropyl. Examples thereof include a group, an n-butyl group, an isobutyl group, a sec-butyl group, a 2-methylpropyl group, and a tert-butyl group. When M is a pyridinium ion, the substituent of the pyridine ring includes a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a carboxy group, and a linear or branched acyl having 2 to 6 carbon atoms. Examples thereof include a group, a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkoxy group having 1 to 6 carbon atoms. As M, alkali metal ion, alkaline earth metal ion, magnesium ion, pyridinium ion (the pyridine ring may have a substituent), or HN ⁺ R ²³ R ²⁴ R ²⁵ (in the formula, the symbol is the above). Ammonium ion (having the same meaning as) is preferable. Examples of the alkali metal ion include lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion. Examples of the alkaline earth metal ion include calcium ion, strontium ion, barium ion, and radium ion. Examples of the organic group of R ²³ , R ²⁴ , and R ²⁵ include those similar to the substituent of the pyridine ring (excluding the halogen atom).

Among these, ^{compounds in which R 26} , R ²⁷ , and R ²⁸ are methyl groups are preferable from the viewpoint of storage stability and color tone stability in the dental composition. On the other hand, examples of ^{Mn + include Li +} , Na ⁺ , K ⁺ , Ca ²⁺ , Mg ²⁺ , and ammonium ions derived from various amines, and examples of amines include ammonia, trimethylamine, diethylamine, and dimethyl. Aniline, ethylenediamine, triethanolamine, N, N-dimethylaminomethacrylate, N, N-dimethylaminobenzoic acid and its alkyl ester, N, N-diethylaminobenzoic acid and its alkyl ester, N, N-bis (2-hydroxy) Ethyl) -p-toluidine and the like can be mentioned.

Among these water-soluble acylphosphine oxides, phenyl (2,4,6-trimethyl-benzoyl) sodium phosphinate salt and phenyl (2,4,6-trimethyl-benzoyl) phosphinic acid lithium salt are particularly preferable.

Water-soluble acylphosphine oxides having such a structure can be synthesized according to a known method, and some of them are also available as commercial products. For example, it can be synthesized by the method disclosed in Japanese Patent Application Laid-Open No. 57-197289, International Publication No. 2014/095724, and the like.

Examples of the water-soluble thioxanthones include 2-hydroxy-3- (9-oxo-9H-thioxanthene-4-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-. 3- (1-Methyl-9-oxo-9H-thioxanthene-4-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (9-oxo-9H-thio) Xanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthene-2-yloxy) -N , N, N-trimethyl-1-propaneaminium chloride, 2-hydroxy-3- (3,4-dimethyl-9H-thioxanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium Chloride, 2-hydroxy-3- (1,3,4-trimethyl-9-oxo-9H-thioxanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride and the like can be used.

The content of the water-soluble photopolymerization initiator (C') is not particularly limited, but from the viewpoint of curability of the dental composition and the like, it is 0 with respect to 100 parts by mass of the total amount of the monomers in the dental composition. The range of 0.01 to 10 parts by mass is preferable, the range of 0.05 to 7 parts by mass is more preferable, and the range of 0.1 to 5 parts by mass is further preferable. If the content (C') of the water-soluble photopolymerization initiator exceeds 10 parts by mass, sufficient adhesive strength may not be obtained if the polymerization performance of the photopolymerization initiator itself is low, and further. May lead to precipitation from the dental composition.

[Chemical polymerization initiator]
The dental composition of the present invention can further contain a chemical polymerization initiator, and an organic peroxide is preferably used. The organic peroxide used as the chemical polymerization initiator is not particularly limited, and known ones can be used. Typical organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, peroxydicarbonates and the like. Specific examples of these organic peroxides include those described in International Publication No. 2008/08977. As the chemical polymerization initiator, one type may be used alone, or two or more types may be used in combination.

Examples of the ketone peroxide include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, methylcyclohexanone peroxide, cyclohexanone peroxide and the like.

Examples of the hydroperoxide include 2,5-dimethylhexane-2,5-dihydroperoxide, diisopropylbenzenehydroperoxide, cumenehydroperoxide, t-butylhydroperoxide, and 1,1,3,3-tetramethylbutylhydro. Peroxide and the like can be mentioned.

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

Examples of the dialkyl peroxide include di-t-butyl peroxide, dicumyl peroxide, t-butyl cumyl peroxide, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, and 1,3-bis. Examples thereof include (t-butylperoxyisopropyl) benzene and 2,5-dimethyl-2,5-di (t-butylperoxy) -3-hexine.

Examples of the peroxyketal include 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, 1,1-bis (t-butylperoxy) cyclohexane, and 2,2-bis (t-). Butane (butylperoxy) butane, 2,2-bis (t-butylperoxy) octane, 4,4-bis (t-butylperoxy) valeric acid-n-butyl and the like can be mentioned.

Examples of the peroxyester include α-cumylperoxyneodecanoate, t-butylperoxyneodecanoate, t-butylperoxypivalate, and 2,2,4-trimethylpentylperoxy-2-ethylhexanoate. , T-amylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, di-t-butylperoxyisophthalate, di-t-butylperoxyhexahydroterephthalate, t-butylperoxy- Examples thereof include 3,3,5-trimethylhexanoate, t-butylperoxyacetate, t-butylperoxybenzoate, and t-butylperoxyvaleric acid.

Examples of the peroxydicarbonate include di-3-methoxybutyl peroxydicarbonate, di (2-ethylhexyl) peroxydicarbonate, bis (4-t-butylcyclohexyl) peroxydicarbonate, diisopropylperoxydicarbonate, and di-n. -Ppropylperoxydicarbonate, di (2-ethoxyethyl) peroxydicarbonate, diallylperoxydicarbonate and the like can be mentioned.

Among these organic peroxides, diacyl peroxide is preferably used from the viewpoint of overall balance of safety, storage stability and radical generation ability, and among them, benzoyl peroxide is particularly preferably used.

[Polymerization accelerator (E)]
In another embodiment of the dental composition of the present invention, a photopolymerization initiator (C), a water-insoluble photopolymerization initiator (D), a water-soluble photopolymerization initiator (C') and / or a chemical polymerization initiator. A polymerization initiator (E) is used together with this. Examples of the polymerization accelerator (E) used in the present invention include amines, sulfic acid and salts thereof, borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, and aldehydes. , Thiol compounds, sulfites, bisulfites, thiourea compounds and the like. The polymerization accelerator (E) may be used alone or in combination of two or more.

The amines used as the polymerization accelerator (E) are divided into aliphatic amines and aromatic amines. Examples of the aliphatic amine include primary aliphatic amines such as n-butylamine, n-hexylamine and n-octylamine; and secondary aliphatic amines such as diisopropylamine, dibutylamine and N-methylethanolamine. N-Methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2- (dimethylamino) ethylmethacrylate, N-methyldiethanolaminedimethacrylate, N-ethyldiethanolaminedimethacrylate, triethanolamine mono Examples thereof include tertiary aliphatic amines such as methacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, tertiary aliphatic amines are preferable from the viewpoint of curability and storage stability of the dental composition, and among them, N-methyldiethanolamine and triethanolamine are more preferably used.

Examples of the aromatic amine include N, N-bis (2-hydroxyethyl) -3,5-dimethylaniline, N, N-bis (2-hydroxyethyl) -p-toluidine, N, N-. Bis (2-hydroxyethyl) -3,4-dimethylaniline, N, N-bis (2-hydroxyethyl) -4-ethylaniline, N, N-bis (2-hydroxyethyl) -4-isopropylaniline, N , N-bis (2-hydroxyethyl) -4-t-butylaniline, N, N-bis (2-hydroxyethyl) -3,5-diisopropylaniline, N, N-bis (2-hydroxyethyl) -3 , 5-Di-t-butylaniline, N, N-dimethylaniline, N, N-dimethyl-p-toluidine, N, N-dimethyl-m-toluidine, N, N-diethyl-p-toluidine, N, N -Dimethyl-3,5-dimethylaniline, N, N-dimethyl-3,4-dimethylaniline, N, N-dimethyl-4-ethylaniline, N, N-dimethyl-4-isopropylaniline, N, N-dimethyl -4-t-butylaniline, N, N-dimethyl-3,5-di-t-butylaniline, ethyl 4- (N, N-dimethylamino) benzoate, 4- (N, N-dimethylamino) benzoate Methyl acid acid, propyl 4- (N, N-dimethylamino) benzoate, n-butoxyethyl 4- (N, N-dimethylamino) benzoate, 2- (methacryloyl) 4- (N, N-dimethylamino) benzoate Examples thereof include oxy) ethyl, 4- (N, N-dimethylamino) benzophenone, butyl 4- (N, N-dimethylamino) benzoate, and a compound represented by the general formula (3). Among these, N, N-bis (2-hydroxyethyl) -p-toluidine, 4- (N, N-dimethylamino) ethyl benzoate, 4 At least one selected from the group consisting of-(N, N-dimethylamino) n-butoxyethyl benzoate and 4- (N, N-dimethylamino) benzophenone is preferably used.

Examples of the sulfinic acid and salts thereof include p-tolusinulfinic acid, sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic acid, and benzene. Sodium sulfinate, potassium benzenesulfinate, lithium benzenesulfinate, calcium benzenesulfinate, 2,4,6-trimethylbenzenesulfinic acid, sodium 2,4,6-trimethylbenzenesulfinate, 2,4,6-trimethylbenzene Potassium sulfinate, lithium 2,4,6-trimethylbenzenesulfinate, calcium 2,4,6-trimethylbenzenesulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate , Potassium 2,4,6-triethylbenzenesulfinate, Lithium 2,4,6-triethylbenzenesulfinate, Calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, 2, , Sodium 4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, calcium 2,4,6-triisopropylbenzenesulfinate Etc., and sodium benzenesulfinate, sodium p-toluenesulfinate, and sodium 2,4,6-triisopropylbenzenesulfinate are particularly preferable.

As the borate compound, an aryl borate compound is preferable. Specific examples of preferably used arylborate compounds include trialkylphenylboron, trialkyl (p-chlorophenyl) boron, and trialkyl (, for example, trialkylphenylborone, trialkyl (p-chlorophenyl) boron, and trialkyl). p-fluorophenyl) boron, trialkyl [3,5-bis (trifluoromethyl) phenyl] boron, trialkyl [3,5-bis (1,1,1,3,3,3-hexafluoro-2-) Methoxy-2-propyl) phenyl] boron, trialkyl (p-nitrophenyl) boron, trialkyl (m-nitrophenyl) boron, trialkyl (p-butylphenyl) boron, trialkyl (m-butylphenyl) boron, Trialkyl (p-butyloxyphenyl) boron, trialkyl (m-butyloxyphenyl) boron, trialkyl (p-octyloxyphenyl) boron and trialkyl (m-octyloxyphenyl) boron (alkyl group is n-butyl At least one selected from the group consisting of a group, an n-octyl group, an n-dodecyl group, etc.) and salts thereof (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium). Salts, tetraethylammonium salts, methylpyridinium salts, ethylpyridinium salts, butylpyridinium salts, methylquinolinium salts, ethylquinolinium salts, butylquinolinium salts, etc.) can be mentioned.

Examples of the borate compound having two aryl groups in one molecule include dialkyldiphenylboron, dialkyldi (p-chlorophenyl) boron, dialkyldi (p-fluorophenyl) boron, and dialkyldi [3,5-bis (tri). Fluoromethyl) phenyl] boron, dialkyldi [3,5-bis (1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl) phenyl] boron, dialkyldi (p-nitrophenyl) boron , Dialkyldi (m-nitrophenyl) boron, Dialkyldi (p-butylphenyl) boron, Dialkyldi (m-butylphenyl) boron, Dialkyldi (p-butyloxyphenyl) boron, Dialkyldi (m-butyloxyphenyl) boron, Dialkyldi ( p-octyloxyphenyl) boron and dialkyldi (m-octyloxyphenyl) boron (alkyl group is at least one selected from the group consisting of n-butyl group, n-octyl group, n-dodecyl group and the like) and These salts (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium salt, tetraethylammonium salt, methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt, methylquinolinium salt, ethylchi) Norinium salt, butylquinolinium salt, etc.) can be mentioned.

Further, examples of the borate compound having three aryl groups in one molecule include monoalkyltriphenylboron, monoalkyltri (p-chlorophenyl) boron, monoalkyltri (p-fluorophenyl) boron, and monoalkyltri. [3,5-bis (trifluoromethyl) phenyl] boron, monoalkyltri [3,5-bis (1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl) phenyl] Boron, monoalkyltri (p-nitrophenyl) boron, monoalkyltri (m-nitrophenyl) boron, monoalkyltri (p-butylphenyl) boron, monoalkyltri (m-butylphenyl) boron, monoalkyltri ( p-Butyloxyphenyl) boron, monoalkyltri (m-butyloxyphenyl) boron, monoalkyltri (p-octyloxyphenyl) boron and monoalkyltri (m-octyloxyphenyl) boron (alkyl group is n-butyl) A group selected from a group, an n-octyl group, an n-dodecyl group, etc.) and salts thereof (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium salt, tetraethylammonium). Salts, methylpyridinium salts, ethylpyridinium salts, butylpyridinium salts, methylquinolinium salts, ethylquinolinium salts, butylquinolinium salts, etc.) can be mentioned.

Further, examples of the borate compound having four aryl groups in one molecule include tetraphenylboron, tetrakis (p-chlorophenyl) boron, tetrakis (p-fluorophenyl) boron, and tetrakis [3,5-bis (trifluoro). Methyl) phenyl] boron, tetrakis [3,5-bis (1,1,1,3,3,3-hexafluoro-2-methoxy-2-propyl) phenyl] boron, tetrakis (p-nitrophenyl) boron, Tetrakiss (m-nitrophenyl) boron, tetrakis (p-butylphenyl) boron, tetrakis (m-butylphenyl) boron, tetrakis (p-butyloxyphenyl) boron, tetrakis (m-butyloxyphenyl) boron, tetrakis (p) -Octyloxyphenyl) boron, tetrakis (m-octyloxyphenyl) boron, (p-fluorophenyl) triphenylboron, [3,5-bis (trifluoromethyl) phenyl] triphenylboron, (p-nitrophenyl) Triphenylboron, (m-butyloxyphenyl) triphenylboron, (p-butyloxyphenyl) triphenylboron, (m-octyloxyphenyl) triphenylboron and (p-octyloxyphenyl) triphenylboron and their Salts (sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt, tetramethylammonium salt, tetraethylammonium salt, methylpyridinium salt, ethylpyridinium salt, butylpyridinium salt, methylquinolinium salt, ethylquinolinium Salts, butylquinolinium salts, etc.).

Among these aryl borate compounds, it is preferable to use a borate compound having 3 or 4 aryl groups in one molecule from the viewpoint of storage stability. In addition, these aryl borate compounds can be used alone or in admixture of two or more.

Examples of the barbituric acid derivative include barbituric acid, 1,3-dimethylbarbituric acid, 1,3-diphenylbarbituric acid, 1,5-dimethylbarbituric acid, 5-butylbarbituric acid, and 5-. Ethyl barbituric acid, 5-isopropyl barbituric acid, 5-cyclohexyl barbituric acid, 1,3,5-trimethylbarbituric acid, 1,3-dimethyl-5-ethylbarbituric acid, 1,3-dimethyl-5 -N-butyl barbituric acid, 1,3-dimethyl-5-isobutyl barbituric acid, 1,3-dimethyl-5-cyclopentyl barbituric acid, 1,3-dimethyl-5-cyclohexyl barbituric acid, 1,3 -Dimethyl-5-phenylbarbituric acid, 1-cyclohexyl-1-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, 5-methylbarbituric acid, 5-propylbarbituric acid, 1,5- Diethyl barbituric acid, 1-ethyl-5-methylbarbituric acid, 1-ethyl-5-isobutylbarbituric acid, 1,3-diethyl-5-butylbarbituric acid, 1-cyclohexyl-5-methylbarbituric acid , 1-cyclohexyl-5-ethylbarbituric acid, 1-cyclohexyl-5-octylbarbituric acid, 1-cyclohexyl-5-hexylbarbituric acid, 5-butyl-1-cyclohexylbarbituric acid, 1-benzyl-5 -Final barbituric acids and thiobarbituric acids, and salts thereof (particularly alkali metal salts or alkaline earth metal salts are preferred). Examples of salts of these barbituric acid derivatives include sodium 5-butylbarbiturate, sodium 1,3,5-trimethylbarbiturate, sodium 1-cyclohexyl-5-ethylbarbiturate and the like.

Particularly suitable barbituric acid derivatives include 5-butyl barbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethyl barbituric acid, 1-benzyl-5-phenylbarbituric acid, and the like. And sodium salts of these barbituric acid derivatives and the like.

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

Of the triazine compounds exemplified above, particularly preferred are 2,4,6-tris (trichloromethyl) -s-triazine in terms of polymerization activity and 2-phenyl-4 in terms of storage stability. , 6-bis (trichloromethyl) -s-triazine, 2- (p-chlorophenyl) -4,6-bis (trichloromethyl) -s-triazine, and 2- (4-biphenylyl) -4,6-bis ( It is trichloromethyl) -s-triazine. The above triazine compound may be used alone or in combination of two or more.

As the copper compound, for example, acetylacetone copper, cupric acetate, copper oleate, cupric chloride, cupric bromide and the like are preferably used.

Examples of the tin compound include di-n-butyl tin dilaurate, di-n-octyl tin dimalate, di-n-octyl tin dilaurate, di-n-butyl tin dilaurate and the like, and di-n-octyl tin dilaurate. Dilaurate and di-n-butyltin dilaurate are preferred.

The vanadium compound is preferably an IV-valent and / or V-valent vanadium compound. Examples of the IV-valent and / or V-valent vanadium compounds include divanadium tetraoxide (IV), vanadium acetylacetonate (IV) oxide, vanadyl oxalate (IV), vanadyl sulfate (IV), and oxobis (1-phenyl). -1,3-Butandionate) vanadium (IV), bis (maltlate) oxovanadium (IV), vanadium pentoxide (V), sodium metavanadate (V), ammon metavanadate (V), etc. Examples thereof include the compounds described in Japanese Patent Application Laid-Open No. 96122.

As the halogen compound, for example, dilauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride, benzyltrimethylammonium chloride, tetramethylammonium chloride, benzyldimethylcetylammonium chloride, dilauryldimethylammonium bromide and the like are preferably used.

Examples of the aldehydes include terephthalaldehyde, benzaldehyde derivatives and the like. Examples of the benzaldehyde derivative include dimethylaminobenzaldehyde, p-methoxybenzaldehyde, p-ethoxybenzaldehyde, pn-octyloxybenzaldehyde and the like. Among these, pn-octyloxybenzaldehyde is preferably used from the viewpoint of curability.

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

Examples of the sulfite include sodium sulfite, potassium sulfite, calcium sulfite, ammonium sulfite and the like.

Examples of the hydrogen sulfite include sodium bisulfite, potassium bisulfite and the like.

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

When the dental composition of the present invention contains a photopolymerization initiator (C-2) as the photopolymerization initiator (C), the compound represented by the general formula (3) is used as the polymerization accelerator (E). It is preferable to use E-1) from the viewpoint of showing high adhesiveness to dentin. In addition to the photopolymerization initiator (C-2), the compound (E-1) is a water-soluble photopolymerization initiator (C-1), a water-soluble photopolymerization initiator (C'), and a water-insoluble photopolymerization initiator. It may be used in combination with (D).

[In the formula, R ¹⁶ and R ¹⁷ are linear or branched alkyl groups having 1 to 4 carbon atoms independently of each other, and R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ and R ²² are mutually independent. Independently, a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH, -COOH or -COOY ² and at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , where Y ² represents an organic cation or an inorganic cation. ]

The alkyl groups of R ¹⁶ to R ²² are not particularly limited as long as they are linear or branched chains having 1 to 4 carbon atoms, and are methyl group, ethyl group, n-propyl group, isopropyl group, n-. Examples thereof include a butyl group, an isobutyl group, a sec-butyl group, a 2-methylpropyl group, and a tert-butyl group. As the alkyl group, a linear alkyl group having 1 to 3 carbon atoms is preferable, a methyl group or an ethyl group is more preferable, and a methyl group is further preferable. The alkoxy group of R ¹⁸ to R ²² is not particularly limited as long as it has a linear or branched chain having 1 to 4 carbon atoms, and is a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, or n. -Butoxy group, sec-butoxy group, tert-butoxy group and the like can be mentioned. As the alkoxy group, a linear alkoxy group having 1 to 3 carbon atoms is preferable, a methoxy group or an ethoxy group is more preferable, and a methoxy group is further preferable.

As Y ² , alkali metal ion, alkaline earth metal ion, magnesium ion, pyridinium ion (the pyridine ring may have a substituent), or HN ⁺ R ²³ R ²⁴ R ²⁵ (in the formula, R ^23). , R ²⁴ , and R ²⁵ are independent of each other, and ammonium ions represented by an organic group or a hydrogen atom) are preferable.

Examples of the alkali metal ion include lithium ion, sodium ion, potassium ion, rubidium ion, and cesium ion. Examples of the alkaline earth metal ion include calcium ion, strontium ion, barium ion, and radium ion. When Y ² is a pyridinium ion, the substituent of the pyridine ring includes a halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom), a carboxy group, and a linear or branched chain having 2 to 6 carbon atoms. Examples thereof include an acyl group, a linear or branched alkyl group having 1 to 6 carbon atoms, and a linear or branched alkoxy group having 1 to 6 carbon atoms. Examples of the ^{ammonium ion represented by HN +} R ²³ R ²⁴ R ²⁵ include those derived from various amines. Examples of amines are ammonia, trimethylamine, diethylamine, dimethylaniline, ethylenediamine, triethanolamine, N, N-dimethylaminomethacrylate, 4- (N, N-dimethylamino) benzoic acid and its alkyl ester, 4- (N). , N-diethylamino) benzoic acid and its alkyl ester, N, N-bis (2-hydroxyethyl) -p-toluidine and the like. Examples of the organic group of R ²³ , R ²⁴ , and R ²⁵ include those similar to the substituent of the pyridine ring (excluding the halogen atom). Of these, as Y ² , lithium ions, sodium ions, potassium ions, calcium ions, magnesium ions, and ^{ammonium ions represented by HN +} R ²³ R ²⁴ R ²⁵ are preferable, and lithium ions, sodium ions, potassium ions, and the like. Calcium ion and magnesium ion are more preferable, and lithium ion and sodium ion are further preferable. For example, ^{Y 2} is a divalent ions (e.g., calcium ions), the "- COOY ^2" is expressed as "-COOCa _1/2". In other words, when Y ² is a divalent ion, the compound (E-1) represented by the general formula (3) forms a dimer.

As the compound (E-1), a compound in which R ¹⁶ and R ¹⁷ are methyl groups or ethyl groups and at least one group of ^{R 18} to R ^{22 is -COOH or -COOY 2} is preferable; R ¹⁶ and R ¹⁷ are methyl or ethyl groups, at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , and at least one of the rest of ^{R 18} to R ^22. Compounds in which one group is -OH or a linear alkoxy group having 1 to 3 carbon atoms are more preferable; R ¹⁶ and R ¹⁷ are methyl groups, and ^{either R 18} or R ¹⁹ is -COOH or-. A ^{compound which is COOY 2} and in which ^{at least one of the at least one group of R 20} to R ²² is a -OH or methoxy group is more preferable; R ¹⁶ and R ¹⁷ are methyl groups, and R ¹⁸ and R are R. If either one of ^{19 is -COOH or -COOY 2} and (i) R ¹⁸ is -COOH or -COOY ² , then R ¹⁹ , R ²¹ and R ²² are hydrogen atoms and R ²⁰ is. Compounds in which -OH or methoxy group and (ii) R ¹⁹ is -COOH or -COOY ² , where R ¹⁸ , R ²⁰ and R ²² are hydrogen atoms and R ²¹ is -OH or methoxy group. Is particularly preferable. Among these, when R ¹⁶ and R ¹⁷ are methyl groups, R ¹⁸ is -COOH or -COOY ² , R ¹⁹ , R ²¹ and R ²² are hydrogen atoms, and R ²⁰ is a methoxy group. Most preferable from the viewpoint of adhesion to dentin.

The compound (E-1) having such a structure can be synthesized according to a known method, and some of them are also available as commercial products.

Specific examples of the compound (E-1) are not particularly limited, but the following can be mentioned.

Sulfic acid and its salts used in the polymerization accelerator (E), borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites. , And specific examples of the thiourea compound include those described in International Publication No. 2008/08977.

The content of the polymerization accelerator (E) used in the present invention is not particularly limited, but from the viewpoint of curability of the obtained dental composition, the total amount of the monomer components in the dental composition is 100 parts by mass. On the other hand, 0.001 to 30 parts by mass is preferable, 0.01 to 20 parts by mass is more preferable, 0.01 to 10 parts by mass is further preferable, 0.05 to 10 parts by mass is particularly preferable, and 0.1 to 10 parts by mass is preferable. 5 parts by mass is most preferable. If the content of the polymerization accelerator (E) is less than 0.001 part by mass, the polymerization does not proceed sufficiently, which may lead to a decrease in adhesiveness. The content of the polymerization accelerator (E) is more preferably 0.05 parts by mass or more. On the other hand, if the content of the polymerization accelerator (E) exceeds 30 parts by mass, or if the polymerization performance of the polymerization initiator itself is low, sufficient adhesiveness may not be obtained, and further, a dental composition. May cause precipitation from. Therefore, the content of the polymerization accelerator (E) is more preferably 20 parts by mass or less.

The dental composition of the present invention preferably further contains a filler (F) depending on the embodiment. The filler (F) is usually roughly classified into an organic filler, an inorganic filler and an organic-inorganic composite filler.

Examples of the material of the organic filler include polymethyl methacrylate, ethyl polymethacrylate, methyl methacrylate-ethyl methacrylate copolymer, crosslinked polymethylmethacrylate, crosslinked polyethyl methacrylate, polyamide, and polyvinyl chloride. Examples thereof include polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylic nitrile-styrene copolymer, acrylic nitrile-styrene-butadiene copolymer, etc., and these may be used alone or It can be used as a mixture of two or more kinds. The shape of the organic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of handleability and mechanical strength of the dental composition, the average particle size of the organic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm. In the present specification, the average particle size of the filler means the average particle size (average primary particle size) of the primary particles of the filler.

Materials for inorganic fillers include quartz, silica, alumina, silica-titania, silica-titania-barium oxide, silica-zirconia, silica-alumina, lanthanum glass, borosilicate glass, soda glass, barium glass, strontium glass, and glass ceramics. , Aluminosilicate glass, barium boroaluminosilicate glass, strontium boroaluminosilicate glass, fluoroaluminosilicate glass, calcium fluoroaluminosilicate glass, strontium fluoroaluminosilicate glass, barium fluoroaluminosilicate glass, strontium calcium fluoroaluminosilicate glass, itterbium oxide, Examples include silica-coated itterbium fluoride. These can also be used alone or in admixture of two or more. The shape of the inorganic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of handleability and mechanical strength of the dental composition, the average particle size of the inorganic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm.

Examples of the shape of the inorganic filler include an amorphous filler and a spherical filler. From the viewpoint of improving the mechanical strength of the dental composition, it is preferable to use a spherical filler as the inorganic filler. Here, the spherical filler is a particle in a direction orthogonal to the maximum diameter of a rounded particle observed in a unit field of view obtained by taking a picture of the filler with a scanning electron microscope (hereinafter abbreviated as SEM). A filler having an average uniformity of 0.6 or more, which is obtained by dividing the diameter by the maximum diameter. The average particle size of the spherical filler is preferably 0.1 μm or more from the viewpoint that the filling rate of the spherical filler in the dental composition does not decrease and the mechanical strength can be maintained, and the surface area of the spherical filler can be obtained by curing. It is preferably 5 μm or less from the viewpoint that it is sufficient to maintain the mechanical strength of the object.

In order to adjust the fluidity of the dental composition, the inorganic filler may be used after surface treatment with a known surface treatment agent such as a silane coupling agent, if necessary. Examples of the surface treatment agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri (β-methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, and 8-methacryloyloxyoxyltrimethoxysilane. Examples thereof include 11-methacryloyloxyundecyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

The organic-inorganic composite filler used in the present invention is obtained by adding a monomer compound to the above-mentioned inorganic filler in advance, forming a paste, polymerizing the mixture, and pulverizing the mixture. As the organic-inorganic composite filler, for example, a TMPT filler (a mixture of trimethylolpropane methacrylate and a silica filler and then pulverized) can be used. The shape of the organic-inorganic composite filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of handleability and mechanical strength of the dental composition, the average particle size of the organic-inorganic composite filler is preferably 0.001 to 50 μm, more preferably 0.001 to 10 μm. ..

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

The laser diffraction / scattering method is specifically measured by a laser diffraction type particle size distribution measuring device (SALD-2300: manufactured by Shimadzu Corporation) using a 0.2% aqueous sodium hexametaphosphate solution as a dispersion medium on a volume basis. be able to.

Specifically, for electron microscope observation, for example, a scanning electron microscope (manufactured by Hitachi, Ltd., S-4000 type) of particles is taken, and the particles (200 or more) observed within the unit field of view of the photograph. The diameter can be determined by measuring using an image analysis type particle size distribution measurement software (Mac-View (Mount Tech Co., Ltd.)). At this time, the particle size of the particles is obtained as an arithmetic mean value of the longest length and the shortest length of the particles, and the average primary particle size is calculated from the number of particles and the particle size thereof.

In the present invention, two or more kinds of fillers having different materials, particle size distributions, and morphologies may be mixed or used in combination, and the fillers (intentionally, within a range that does not impair the effects of the present invention). Particles other than F) may be contained as impurities. As the filler in the present invention, a commercially available product may be used.

The content of the filler (F) used in the present invention is not particularly limited, and is preferably in the range of 0.1 to 30% by mass, preferably in the range of 0.5 to 20% by mass, based on the total mass of the dental composition. Is more preferable, and the range of 1.0 to 10% by mass is further preferable.

The dental composition of the present invention contains at least water as the solvent (G). Examples of the solvent (G) include organic solvents and the like. The solvent (G) is preferably used in the form of a mixed solvent of water and an organic solvent. Further, depending on the embodiment, the inclusion of the organic solvent may not be required.

When the dental composition of the present invention contains water, the decalcification action of the monomer (A) having an acidic group on the dentin is promoted. As the water, it is necessary to use water that does not substantially contain impurities that adversely affect the adhesiveness, and distilled water or ion-exchanged water is preferable. If the water content is too small, the effect of promoting the decalcification action may not be sufficiently obtained, and if it is too large, the adhesiveness may be lowered. Of the solvent (G), the content of water is preferably 1 to 500 parts by mass, more preferably 5 to 300 parts by mass, and further 10 to 200 parts by mass with respect to 100 parts by mass of the total amount of the monomer components. preferable.

When the dental composition of the present invention contains an organic solvent, the adhesiveness, coatability, and permeability to the dentin can be further improved, and the separation of each component of the composition can be further prevented. The organic solvent usually has a boiling point of 150 ° C. or lower 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 water at an arbitrary ratio. An organic solvent that is soluble in water is used.

Examples of the organic solvent 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 and acetic acid. Ethyl, butyl acetate and the like can be mentioned. Among these, the organic solvent is preferably a water-soluble organic solvent in consideration of both safety to the living body and ease of removal based on volatility, and specifically, ethanol, 2-propanol, 2 -Methyl-2-propanol, acetone, and tetrahydrofuran are preferable, and ethanol, 2-propanol, 2-methyl-2-propanol and tetrahydrofuran are more preferable.

The total content of the solvent (G) is preferably 1 to 2000 parts by mass, more preferably 2 to 1000 parts by mass, still more preferably 3 to 500 parts by mass, based on 100 parts by mass of the total amount of the monomer components. In one embodiment, the total content of the solvent (G) is preferably 0.1% by mass or more, more preferably 1% by mass or more, and 3% by mass, based on the entire dental composition. The above is more preferable, and 5% by mass or more is particularly preferable. Further, in the embodiment, the total content of the solvent (G) is preferably 90% by mass or less, more preferably 70% by mass or less, and 60% by mass or less with respect to the entire dental composition. Is more preferable, and 50% by mass or less is particularly preferable.

[Fluoride ion-releasing substance]
The dental composition of the present invention may further contain a fluoride ion-releasing substance. By blending a fluoride ion-releasing substance, a dental composition capable of imparting acid resistance to the dentin can be obtained. Examples of the fluorine ion-releasing substance include metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and itterbium fluoride. The above-mentioned fluoride ion-releasing substance may be used alone or in combination of two or more.

In addition, additives such as pH adjusters, polymerization inhibitors, thickeners, colorants, fluorescent agents, and fragrances may be added to the dental composition as long as the effects of the present invention are not impaired. As the additive, one type may be used alone, or two or more types may be used in combination. The dental compositions of the present invention include cetylpyridinium chloride, benzalkonium chloride, (meth) acryloyloxidedecylpyridinium bromide, (meth) acryloyloxyhexadecylpyridinium chloride, (meth) acryloyloxydecylammonium chloride, triclosan and the like. May contain antibacterial substances. The dental composition of the present invention may contain known dyes and pigments as colorants. In addition, the dental composition of the present invention may contain a prepolymer (oligomer) having a polymerizable group (for example, a (meth) acrylic group). The prepolymer is not particularly limited, and examples thereof include those having a weight average molecular weight of 5,000 to 50,000.

The dental composition of the present invention comprises a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), and a water-insoluble photopolymerization initiator (D). , 0.1% by mass based on the total mass of the dental composition, with respect to the content of other components other than the polymerization accelerator (E), the filler (F), the solvent (G), the polymerization inhibitor and the colorant. It is preferably less than, more preferably less than 0.01% by mass, and even more preferably less than 0.001% by mass.

The dental composition of the present invention preferably contains each component so that the pH of the liquid (composition) is in the range of 1.5 to 4.0, and the pH is in the range of 1.8 to 3.5. It is more preferable that the pH is in the range of 2.0 to 3.0. If the pH of the composition is less than 1.5, over-decalcification may occur during so-called total etching, which is applied to the tooth surface after the phosphoric acid etching treatment, and the adhesion may be deteriorated. On the other hand, if the pH of the composition exceeds 4.0, the decalcification action may be reduced and the adhesion during self-etching may be reduced.

The dental composition of the present invention is suitably used as, for example, a dental bonding material, a dental primer or a dental coating material. At this time, the components of the dental composition of the present invention may be a one-component type or a one-bottle type, or may be used as a two-component type or a two-bottle type divided into two, but are used as a one-component type or a one-bottle type. Is preferable. Hereinafter, specific embodiments when the dental composition is applied will be shown.

<Dental bonding material>
One of the preferred embodiments of the dental composition of the present invention is a dental bonding material. The dental bonding material can be subjected to a decalcification step, a permeation step, and a hardening step in one step. Examples of the dental bonding material include a two-bottle type in which two liquids divided into liquid A and liquid B are mixed immediately before use, and a one-bottle type in which one liquid can be used as it is. Among them, the one-bottle type has a great advantage in use because the process is simplified. As the dental bonding material, a self-etching primer or the like may be used as a pretreatment material. The dental composition used for this dental bonding material includes a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), and a water-insoluble photopolymerization. It preferably contains an initiator (D), a polymerization accelerator (E), a filler (F), and a solvent (G). Further, as the dental bonding material, it is more preferable to use the photopolymerization initiator (C) and the water-insoluble photopolymerization initiator (D) in combination.

The content of each component in the dental bonding material is 1 to 90 parts by mass of the monomer (A) having an acidic group and 1 to 90 parts by mass of the acidic group with respect to 100 parts by mass of the total amount of the monomer components in the dental composition. It is preferable to contain 1 to 98 parts by mass of the monomer (B) having no acidic group; 5 to 80 parts by mass of the monomer (A) having an acidic group, and 5 to 95 parts by mass of the monomer (B) having no acidic group. It is more preferable to include 5 to 70 parts by mass of the monomer (A) having an acidic group, and 10 to 90 parts by mass of the monomer (B) having no acidic group. Further, with respect to 100 parts by mass of the total amount of the monomer component, 0.001 to 30 parts by mass of the photopolymerization initiator (C), 0.001 to 30 parts by mass of the water-insoluble photopolymerization initiator (D), and polymerization. It preferably contains 0.001 to 20 parts by mass of the accelerator (E), 0 to 100 parts by mass of the filler (F), and 1 to 2000 parts by mass of the solvent (G); 0.05 to 0.05 parts by mass of the photopolymerization initiator (C). 10 parts by mass, 0.05 to 10 parts by mass of the water-insoluble photopolymerization initiator (D), 0.05 to 10 parts by mass of the polymerization accelerator (E), 1 to 75 parts by mass of the filler (F), and the solvent (G). ) More preferably, it contains 2 to 1000 parts by mass.

<Dental primer>
One of the preferred embodiments of the dental composition of the present invention is a dental primer. The dental primer can be subjected to a decalcification step and a permeation step in one step. Examples of the dental primer include a two-bottle type in which two liquids divided into liquid A and liquid B are mixed immediately before use, and a one-bottle type in which one liquid can be used as it is. Among them, the one-bottle type has a great advantage in use because the process is simplified. As the dental primer, a dental bonding material may be used after the primer treatment. The dental composition used for the dental primer of the present invention includes a monomer having an acidic group (A), a monomer having no acidic group (B), a photopolymerization initiator (C), and a water-insoluble light. It preferably contains a polymerization initiator (D), a polymerization accelerator (E), and a solvent (G). Further, it is more preferable to use the photopolymerization initiator (C) and the water-insoluble photopolymerization initiator (D) in combination. Further, the dental bonding material used after the treatment of the dental primer of the present invention may be the dental bonding material of the present invention or a known dental bonding material. The known dental bonding material is not particularly limited, and a commercially available product can be used.

The content of each component in the dental primer has 1 to 90 parts by mass of the monomer (A) having an acidic group and an acidic group with respect to 100 parts by mass of the total amount of the monomer components in the dental composition. Non-monomer (B) preferably contains 1 to 98 parts by mass; 5 to 80 parts by mass of the monomer (A) having an acidic group, and 5 to 95 parts by mass of the monomer (B) having no acidic group. It is more preferable to include 5 to 70 parts by mass of the monomer (A) having an acidic group, and 10 to 90 parts by mass of the monomer (B) having no acidic group. Further, with respect to 100 parts by mass of the total amount of the monomer component, 0.001 to 30 parts by mass of the photopolymerization initiator (C), 0.001 to 30 parts by mass of the water-insoluble photopolymerization initiator (D), and polymerization. It preferably contains 0.001 to 20 parts by mass of the accelerator (E) and 1 to 2000 parts by mass of the solvent (G); 0.05 to 10 parts by mass of the photopolymerization initiator (C), water-insoluble photopolymerization initiation. It is more preferable to contain 0.05 to 10 parts by mass of the agent (D), 0.05 to 10 parts by mass of the polymerization accelerator (E), and 2 to 1000 parts by mass of the solvent (G). The dental primer may contain a filler (F). Certain embodiments include dental compositions that do not contain the filler (F). A dental bonding material may be used as a dental primer.

<Dental coating material>
One of the preferred embodiments of the dental composition of the present invention is a dental coating material. That is, it can be used as a coating material for protecting the surface of various adherends (dental substance, metal, ceramics, resin, etc.). In particular, when used as a coating material on exposed dentin, which has a large effect on the pulp (sometimes called nerves), it not only protects against wear and irritation, but also suppresses hypersensitivity and prevents caries infection. , A dental composition effective for dental treatment such as suppression of the occurrence of postoperative pain can be provided. The types of components preferable for the dental composition used in the present dental coating material and their contents are the same as those in the above-mentioned preferred embodiments for the dental bonding material.

The dental composition according to the present invention exhibits excellent adhesiveness not only to tooth substance but also to crown restoration materials (metals, porcelains, ceramics, composite resin cured products, etc.) that are broken in the oral cavity. To do. When the dental composition according to the present invention is used for adhering a crown restoration material, the dental composition according to the present invention is used as a primer such as a commercially available primer for adhering metal or a primer for adhering porcelain; hypochlorite. It may be used in combination with a tooth surface cleaning agent such as acid salt or hydrogen peroxide solution.

These dental compositions can be prepared and used according to a conventional method.

In any of the preferred embodiments of the dental bonding material, the dental primer, and the dental coating material described above, the content of each component can be appropriately changed based on the description in the above specification, and any component can be used. Can be added, deleted, etc.

The present invention includes embodiments in which the above configurations are variously combined within the scope of the technical idea of the present invention as long as the effects of the present invention are exhibited.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples. Also, not all combinations of features described in the examples are essential to the solution of the present invention. The components used in the following examples and comparative examples, their abbreviations, structures, and test methods are as follows.

[Monomer having an acidic group (A)]
MDP: 10-methacryloyloxydecyldihydrogen phosphate

[Monomer having no acidic group (B)]
-Hydrophilic monomer having no acidic group (B-1)
DEAA: N, N-diethylacrylamide HEMA: 2-hydroxyethyl methacrylate

-Hydrophobic monomer having no acidic group (B-2)
MAEA: N-methacryloyloxyethyl acrylamide Bis-GMA: 2,2-bis [4- (3-methacryloyloxy-2-hydroxypropoxy) phenyl] propane UDMA: 2,2,4-trimethylhexamethylenebis (2-carbamoyl) Oxyethyl) dimethacrylate NPDMA: neopentyl glycol dimethacrylate

[Photopolymerization Initiator (C)]
-Photopolymerization initiator (C-1)
BAPO-PEG950: A compound represented by the following formula (5) using polyethylene glycol methyl ether methacrylate of Mn = 950 Da as a raw material (absorbance at 420 nm: 0.012).
A compound represented by the following formula (5) using BAPO-PEG9: n = 9 polyethylene glycol methyl ether methacrylate as a raw material (absorbance at 420 nm: 0.011).

-Photopolymerization initiator (C-2)
CQ-COONa: Compound represented by the following formula (6) (absorbance at 420 nm: 0.016)

CQ-COOLi: Compound represented by the following formula (7) (absorbance at 420 nm: 0.017)

[Water-insoluble photopolymerization initiator (D) that does not fall under either of the photopolymerization initiators (C-1) and (C-2)]
CQ: dl-camphorquinone TMDPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (absorbance at 420 nm: not measurable because it is insoluble in water)
BAPO: Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (absorbance at 420 nm: cannot be measured because it is insoluble in water)

[Water-soluble photopolymerization initiator (C') that does not fall under either photopolymerization initiator (C-1) or (C-2)]
TPO-Li: Lithium phenyl (2,4,6-trimethylbenzoyl) phosphinate (absorbance at 420 nm: 0.002)
QTX: 2-Hydroxy-3- (3,4-dimethyl-9-oxo-9H-thioxanthene-2-yloxy) -N, N, N-trimethyl-1-propaneaminium chloride

[Polymerization accelerator (E)]
DABE: 4- (N, N-dimethylamino) ethyl benzoate DEPT: N, N-bis (2-hydroxyethyl) -p-toluidine, polymerization accelerator (E-1)
Polymerization accelerator 1: Compound represented by the following formula (8)

Polymerization accelerator 2: Compound represented by the following formula (9)

Polymerization accelerator 3: Compound represented by the following formula (10)

[Filler (F)]
R972: Fine particle silica "Aerosil (registered trademark) R972" manufactured by Nippon Aerosil Co., Ltd., average particle size: 16 nm
Ar380: Fine particle silica "Aerosil (registered trademark) 380" manufactured by Nippon Aerosil Co., Ltd., average particle size: 7 nm

[Other]
BHT: 2,6-di-t-butyl-4-methylphenol (stabilizer (polymerization inhibitor))

[Example 1 and Comparative Example 1 Application of dental composition to dental bonding material]
<Examples 1-1 to 1-16 and Comparative Examples 1-1 to 1-4>
By mixing each component shown in Table 1 at room temperature, the dental bonding materials of Examples 1-1 to 1-16 and the dental bonding materials of Comparative Examples 1-1 to 1-4 were prepared. Then, using these dental bonding materials, the tensile adhesive strength to the dentin was measured according to the method described later. Table 1 shows the test results of the dental bonding materials of each Example and Comparative Example.

[Tension adhesion strength to dentin that has not been subjected to phosphoric acid etching treatment]
The labial surface of the bovine mandibular anterior teeth was polished with # 80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water to obtain a sample in which the flat surface of dentin was exposed. The obtained sample was further polished with # 1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water. After polishing was completed, water on the surface was air-blown to dry and a smooth surface was obtained. An adhesive tape having a diameter of 3 mm and a thickness of about 150 μm was attached to the smooth surface after drying to define the adhesive area.

The dental bonding material prepared in each Example and Comparative Example was applied into the above round hole with a brush, left for 3 seconds, and then the surface was air blown. Subsequently, the applied dental bonding material was cured by irradiating with a dental LED light irradiator (manufactured by Morita Co., Ltd., trade name "Pencure 2000") for 10 seconds.

The surface of the cured product of the obtained dental bonding material is filled with a dental composite resin (manufactured by Clarenoritake Dental Co., Ltd., trade name "Clearfill (registered trademark) AP-X"), and a release film (polyester) is used. Covered. Next, the slide glass was placed on the release film and pressed against the release film to smooth the coated surface of the composite resin. Subsequently, the composite resin was irradiated with light for 20 seconds using the irradiator "Pencure 2000" through the release film to cure the composite resin.

A stainless steel columnar rod (diameter) was used on the surface of the cured product of the obtained dental composite resin using a commercially available dental resin cement (manufactured by Clarenoritake Dental Co., Ltd., trade name "Panavia (registered trademark) 21"). One end face (circular cross section) (7 mm, length 2.5 cm) was bonded. After adhesion, the sample was allowed to stand at room temperature for 30 minutes and then immersed in distilled water to obtain an adhesion test sample. The adhesion test test sample was allowed to stand in an incubator maintained at 37 ° C. for 24 hours, and then the tensile adhesion strength was measured immediately (N = 10).

Adhesion test The tensile adhesive strength of the test sample was measured with a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) at a crosshead speed of 2 mm / min, and the average value was pulled. Adhesive strength.

[Tensile adhesion strength to dentin subjected to phosphoric acid etching treatment]
The labial surface of the bovine mandibular anterior teeth was polished with # 80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water to obtain a sample in which the flat surface of dentin was exposed. The obtained sample was further polished with # 1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water. After polishing was completed, water on the surface was air-blown to dry and a smooth surface was obtained.

A dental phosphoric acid etching material (manufactured by Clarenoritake Dental Co., Ltd., trade name "K Etchant Syringe") is slowly extruded onto the smooth surface after drying, applied to dentin, left for 10 seconds, washed with water and dried. did. An adhesive tape having a diameter of 3 mm and a thickness of about 150 μm was attached to the smooth surface after drying to define the adhesive area.

The dental bonding material prepared in each Example and Comparative Example was applied into the above round hole with a brush, left for 3 seconds, and then the surface was air blown. Subsequently, the applied dental bonding material was cured by irradiating with a dental LED light irradiator (manufactured by Morita Co., Ltd., trade name "Pencure 2000") for 10 seconds.

The surface of the cured product of the obtained dental bonding material is filled with a dental composite resin (manufactured by Clarenoritake Dental Co., Ltd., trade name "Clearfill (registered trademark) AP-X"), and a release film (polyester) is used. Covered. Next, the slide glass was placed on the release film and pressed against the release film to smooth the coated surface of the composite resin. Subsequently, the composite resin was irradiated with light for 20 seconds using the irradiator "Pencure 2000" through the release film to cure the composite resin.

A stainless steel columnar rod (diameter) was used on the surface of the cured product of the obtained dental composite resin using a commercially available dental resin cement (manufactured by Clarenoritake Dental Co., Ltd., trade name "Panavia (registered trademark) 21"). One end face (circular cross section) (7 mm, length 2.5 cm) was bonded. After adhesion, the sample was allowed to stand at room temperature for 30 minutes and then immersed in distilled water to obtain an adhesion test sample. The adhesion test test sample was allowed to stand in an incubator maintained at 37 ° C. for 24 hours, and then the tensile adhesion strength was measured immediately (N = 10).

Adhesion test The tensile adhesive strength of the test sample was measured with a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) at a crosshead speed of 2 mm / min, and the average value was pulled. Adhesive strength.

As shown in Table 1, the dental bonding materials (Examples 1-1 to 1-16) according to the present invention exhibited an adhesive strength of 15 MPa or more with respect to dentin without phosphoric acid etching treatment. It exhibited an adhesive strength of 13 MPa or more with respect to dentin with phosphoric acid etching treatment. On the other hand, in the composition not containing the monomer (A) having an acidic group (Comparative Example 1-1), almost no adhesive strength was exhibited. Further, in the composition (Comparative Example 1-2) containing only the water-insoluble photopolymerization initiator (D) without containing the photopolymerization initiator (C), a high adhesive strength of 16 MPa is exhibited without the phosphoric acid etching treatment. However, since it did not contain the photopolymerization initiator (C), it was 8 MPa with the phosphoric acid etching treatment. Further, in the composition containing only the water-soluble photopolymerization initiator (C') (Comparative Examples 1-3, 1-4), the dentate without the phosphoric acid etching treatment was 6 to 7 MPa with the phosphoric acid etching treatment. It was 3 MPa with respect to the dentin, and it was confirmed that the adhesive strength to the dentin was not sufficient regardless of the presence or absence of the phosphoric acid etching treatment.

[Example 2 and Comparative Example 2 Application of dental composition to dental primer]
<Examples 2-1 to 2-9 and Comparative Examples 2-1 to 2-3>
By mixing each component shown in Table 2 at room temperature, the dental primers of Examples 2-1 to 2-9 and the dental primers of Comparative Examples 2-1 to 2-3 were prepared. In addition, a dental bonding material having the composition shown in Table 3 was prepared. Then, using these dental primers and dental bonding materials, the tensile adhesive strength to dentin was measured according to the method described later. Table 2 shows the test results of the dental primers of each example and comparative example.

[Tension adhesion strength to dentin that has not been subjected to phosphoric acid etching treatment]
The labial surface of the bovine mandibular anterior teeth was polished with # 80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water to obtain a sample in which the flat surface of dentin was exposed. The obtained sample was further polished with # 1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water. After polishing was completed, water on the surface was air-blown to dry and a smooth surface was obtained. An adhesive tape having a diameter of 3 mm and a thickness of about 150 μm was attached to the smooth surface after drying to define the adhesive area.

The dental primers prepared in each Example and Comparative Example were applied into the above round holes with a brush, left for 20 seconds, and then the surface was air blown. Subsequently, the dental bonding material having the composition shown in Table 3 was overcoated on the surface coated with the dental primer and dried. Subsequently, the applied dental bonding material was cured by irradiating with a dental LED light irradiator (manufactured by Morita Co., Ltd., trade name "Pencure 2000") for 10 seconds.

The surface of the cured product of the obtained dental bonding material is filled with a dental composite resin (manufactured by Clarenoritake Dental Co., Ltd., trade name "Clearfill (registered trademark) AP-X"), and a release film (polyester) is used. Covered. Next, the slide glass was placed on the release film and pressed against the release film to smooth the coated surface of the composite resin. Subsequently, the composite resin was irradiated with light for 20 seconds using the irradiator "Pencure 2000" through the release film to cure the composite resin.

A stainless steel columnar rod (diameter) was used on the surface of the cured product of the obtained dental composite resin using a commercially available dental resin cement (manufactured by Clarenoritake Dental Co., Ltd., trade name "Panavia (registered trademark) 21"). One end face (circular cross section) (7 mm, length 2.5 cm) was bonded. After adhesion, the sample was allowed to stand at room temperature for 30 minutes and then immersed in distilled water to obtain an adhesion test sample. The adhesion test test sample was allowed to stand in an incubator maintained at 37 ° C. for 24 hours, and then the tensile adhesion strength was measured immediately (N = 10).

Adhesion test The tensile adhesive strength of the test sample was measured with a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) at a crosshead speed of 2 mm / min, and the average value was pulled. Adhesive strength.

[Tensile adhesion strength to dentin subjected to phosphoric acid etching treatment]
The labial surface of the bovine mandibular anterior teeth was polished with # 80 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water to obtain a sample in which the flat surface of dentin was exposed. The obtained sample was further polished with # 1000 silicon carbide paper (manufactured by Nihon Kenshi Co., Ltd.) under running water. After polishing was completed, water on the surface was air-blown to dry and a smooth surface was obtained.

A dental phosphoric acid etching material (manufactured by Clarenoritake Dental Co., Ltd., trade name "K Etchant Syringe") is slowly extruded onto the smooth surface after drying, applied to dentin, left for 10 seconds, washed with water and dried. did. An adhesive tape having a diameter of 3 mm and a thickness of about 150 μm was attached to the smooth surface after drying to define the adhesive area.

The dental primers prepared in each Example and Comparative Example were applied into the above round holes with a brush, left for 20 seconds, and then the surface was air blown. Subsequently, the dental bonding material having the composition shown in Table 3 was overcoated on the surface coated with the dental primer and dried. Subsequently, the applied dental bonding material was cured by irradiating with a dental LED light irradiator (manufactured by Morita Co., Ltd., trade name "Pencure 2000") for 10 seconds.

The surface of the cured product of the obtained dental primer and dental bonding material is filled with a dental composite resin (manufactured by Clarenoritake Dental Co., Ltd., trade name "Clearfill (registered trademark) AP-X"), and a release film is released. Covered with (polyester). Next, the slide glass was placed on the release film and pressed against the release film to smooth the coated surface of the composite resin. Subsequently, the composite resin was irradiated with light for 20 seconds using the irradiator "Pencure 2000" through the release film to cure the composite resin.

A stainless steel columnar rod (diameter) was used on the surface of the cured product of the obtained dental composite resin using a commercially available dental resin cement (manufactured by Clarenoritake Dental Co., Ltd., trade name "Panavia (registered trademark) 21"). One end face (circular cross section) (7 mm, length 2.5 cm) was bonded. After adhesion, the sample was allowed to stand at room temperature for 30 minutes and then immersed in distilled water to obtain an adhesion test sample. The adhesion test test sample was allowed to stand in an incubator maintained at 37 ° C. for 24 hours, and then the tensile adhesion strength was measured immediately (N = 10).

Adhesion test The tensile adhesive strength of the test sample was measured with a universal testing machine (Autograph AG-I 100 kN, manufactured by Shimadzu Corporation) at a crosshead speed of 2 mm / min, and the average value was pulled. Adhesive strength.

As shown in Table 2, the dental primers (Examples 2-1 to 2-9) according to the present invention exhibited an adhesive strength of 24 MPa or more with respect to dentin without phosphoric acid etching treatment, and phosphorus. It exhibited an adhesive strength of 21 MPa or more with respect to the dentin with the acid etching treatment. On the other hand, in the composition (Comparative Example 2-1) containing only the water-insoluble photopolymerization initiator (D) without containing the photopolymerization initiator (C), a high adhesive strength of 26 MPa is exhibited without the phosphoric acid etching treatment. However, since it did not contain the photopolymerization initiator (C), it was 15 MPa with the phosphoric acid etching treatment. Further, in the composition containing the water-soluble photopolymerization initiator (C') (Comparative Examples 2-2, 2-3), 14 to 16 MPa of the dentin without the phosphoric acid etching treatment, and the ivory with the phosphoric acid etching treatment It was 10 MPa with respect to the quality, and it was confirmed that the adhesive strength to the dentin was not sufficient regardless of the presence or absence of the phosphoric acid etching treatment.

The dental composition according to the present invention is suitably used as a dental bonding material, a dental primer, and a dental coating material in the field of dentistry.

Claims (14)

1. The photopolymerization initiator (C) containing a monomer (A) having an acidic group, a monomer (B) having no acidic group, a photopolymerization initiator (C), and water causes intramolecular cleavage. It is represented by the photopolymerization initiator (C-1) and / or the general formula (2), which is a type and has an absorbance at 420 nm of 0.007 or more when dissolved in water at a concentration of 0.01 wt%. A dental composition comprising a photopolymerization initiator (C-2).
   

   

   [In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ and R ⁸ are independent of each other and have a hydrogen atom and a linear or branched chain having 1 to 4 carbon atoms. An alkyl group, a linear or branched-chain alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH or -COOY ¹ , and at least one of ^{R 1} to R ^{8 is -COOY 1} . , Y ¹ represents an organic cation or an inorganic cation. ]
2. The dental composition according to claim 1, wherein the monomer (B) having no acidic group contains a hydrophilic monomer (B-1) having no acidic group.
3. The dental composition according to claim 1 or 2, wherein the content of the water is 1 to 500 parts by mass with respect to 100 parts by mass of the total amount of the monomer components.
4. The dental composition according to any one of claims 1 to 3, wherein the photopolymerization initiator (C-1) is a compound represented by the general formula (1).
   

   

   [In the formula, R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ and R ¹⁴ are linear or branched chain alkyl groups or halogen atoms having 1 to 4 carbon atoms independently of each other. X is a linear or branched alkylene group having 1 to 4 carbon atoms, R ¹⁵ is represented by -CH (CH ₃ ) COO (C ₂ H ₄ O) _n CH ₃ , and n is 1 to 1000. Represents an integer of. ]
5. The dental composition according to claim 4, wherein X is a methylene group.
6. Claimed that the photopolymerization initiator (C) contains the photopolymerization initiator (C-2) and further contains the compound (E-1) represented by the general formula (3) as the polymerization accelerator (E). Item 2. The dental composition according to any one of Items 1 to 5.
   

   

   [In the formula, R ¹⁶ and R ¹⁷ are linear or branched alkyl groups having 1 to 4 carbon atoms independently of each other, and R ¹⁸ , R ¹⁹ , R ²⁰ , R ²¹ and R ²² are mutually independent. Independently, a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, a linear or branched alkoxy group having 1 to 4 carbon atoms, a halogen atom, -OH, -COOH or -COOY ² and at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , where Y ² represents an organic cation or an inorganic cation. ]
7. R ¹⁶ and R ¹⁷ are methyl or ethyl groups, and at least one of ^{R 18} to R ^{22 is -COOH or -COOY 2} , and at least one of the rest of ^{R 18} to R ^22. The dental composition according to claim 6, wherein the group is —OH or a linear alkoxy group having 1 to 3 carbon atoms.
8. Wherein the photopolymerization initiator (C) is the photopolymerization initiator ^(C-2), at least one group of R 1 ~ ^{R 8} is -COOY ^1, the remaining groups of R 1 ~ ^{R 8} The dental composition according to any one of claims 1 to 7, wherein is a hydrogen atom or a methyl group.
9. If R ¹ is a hydrogen atom or a methyl group, R ² is a methyl group or -COOY ¹ , R ³ is a methyl group, and (i) R ² is a methyl group, then R ⁴ to R ⁸ According to claim 8, when any one is -COOY ¹ , the other four are hydrogen atoms, and (ii) R ² is -COOY ¹ , ^{all R 4} to R ⁸ are hydrogen atoms. Dental composition.
10. The dental composition according to any one of claims 1 to 9, wherein the monomer (A) having an acidic group contains a monomer having a phosphoric acid group.
11. Any one of claims 1 to 10, further comprising a water-insoluble photopolymerization initiator (D) that does not fall under any of the photopolymerization initiator (C-1) and the photopolymerization initiator (C-2). The dental composition according to the section.
12. The dental composition according to claim 11, wherein the mass ratio of the photopolymerization initiator (C) to the water-insoluble photopolymerization initiator (D) is 10: 1 to 1:10.
13. A dental bonding material containing the dental composition according to any one of claims 1 to 12.
14. A dental primer containing the dental composition according to any one of claims 1 to 12.