JP7708638B2 - dental curable composition - Google Patents

Description

The present invention relates to a dental hardenable composition used in dental treatment for bonding dental prostheses such as crowns, inlays, and bridges to tooth structure, and for building abutments. More specifically, the present invention relates to a dental hardenable composition that exhibits excellent mechanical strength of the hardened product when the pH is 7 or higher.

Adhesive materials and filling and restorative materials are widely used to repair missing parts of teeth damaged by caries, fractures, etc. Resin-based dental hardenable compositions consisting of polymerizable monomers, polymerization initiators, fillers, etc. are commonly used as adhesive materials and filling and restorative materials used to repair teeth.

In order to polymerize and harden these dental hardenable compositions, a redox-type polymerization initiator system consisting of an oxidizing agent, a reducing agent, etc. may be used. In this case, the oxidizing agent and the reducing agent of the polymerization initiator system are packaged, for example, in a first agent containing an oxidizing agent and a second agent containing a reducing agent, and the dental hardenable composition is provided to the dentist who is the user. Just before the dentist uses the dental hardenable composition, the first agent containing an oxidizing agent and the second agent containing a reducing agent are mixed, whereby radicals are generated by a redox reaction, and the polymerization and hardening of the dental hardenable composition proceeds.

In recent years, polymerization initiator systems using organic peroxides as oxidizing agents have been proposed. For example, Patent Document 1 describes the use of a combination of organic peroxides, aryl borate compounds, and vanadium compounds to obtain high adhesive strength to tooth structure.

Patent Document 2 also describes the use of a combination of an organic peroxide, a sulfinate, a vanadium compound, and an aromatic amine compound, which results in storage stability that does not cause a significant delay in curing time even after long-term storage at room temperature or higher.

JP 2004-043427 A International Publication No. 2019/031488

As a result of the study by the present inventors, it was confirmed that the polymerization initiator system of the dental hardenable composition disclosed in Patent Documents 1 and 2 contains a polymerizable monomer containing an acidic group, and hardening proceeds well when the pH after mixing is less than 7, but there is room for improvement in hardening under conditions of pH 7 or higher. On the other hand, if the dental hardenable composition is to be highly functionalized to impart the effect of remineralizing dentin and promoting the healing of dental pulp tissue, the dental hardenable composition needs to contain a large amount of calcium-containing compounds or fluorides. When a large amount of calcium-containing compounds or fluorides is contained, the pH after mixing becomes 7 or higher, and good hardening properties are required under these conditions. Therefore, it can be said that the polymerization initiator system disclosed in Patent Documents 1 and 2 has room for improvement in the mechanical strength of the hardened product under conditions of a pH after mixing of 7 or higher.

The present invention aims to provide a dental hardenable composition that has excellent mechanical strength of the hardened product even when the pH is 7 or higher.

As a result of intensive research, the inventors discovered that the above problems could be solved by combining a polymerizable monomer that does not have an acidic group, a polymerization initiator, a transition metal compound, and a specific ligand compound, and after further research, they completed the present invention.

That is, the present invention includes the following inventions.
[1] A composition comprising a polymerizable monomer (A) having no acidic group, a polymerization initiator (B), a transition metal compound (C), and a ligand compound (D),
A dental hardenable composition, wherein the ligand compound (D) is at least one compound selected from the group consisting of a ligand containing a phosphorus atom and a ligand containing a nitrogen atom, and the dental hardenable composition has a pH of 7 or more.
[2] The ligand compound (D) is a ligand containing a phosphorus atom,
The dental curable composition according to [1], wherein the ligand containing a phosphorus atom is at least one compound selected from the group consisting of a compound represented by the following general formula (1), a compound represented by the general formula (2), a compound represented by the general formula (3), and a compound represented by the general formula (4).
(R ₁ to R ₁₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent.)
(R ₁₆ to R ₃₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and X ₁ represents a divalent aliphatic group which may have a substituent.)
(Each Ar independently represents a group represented by the following general formula (3-a).)
(Z ₁ to Z ₃ each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and at least one of Z ₁ to Z ₃ is a hydrogen atom.)
P(OY ₁ ) ₃ (4)
(Each _Y1 independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent.)
[3] The dental curable composition according to [2], wherein the ligand containing a phosphorus atom is a compound represented by general formula (1).
[4] The ligand compound (D) is a ligand containing a nitrogen atom,
the nitrogen atom-containing ligand is at least one compound selected from the group consisting of a compound represented by general formula (5), a compound represented by general formula (6), and a multidentate ligand containing a nitrogen-containing heterocycle (7),
The dental curable composition according to [1], wherein the polydentate ligand (7) is a bidentate or higher ligand compound that contains a heterocycle containing a nitrogen atom and has two or more nitrogen atoms in the molecule.
R ₃₆ R ₃₇ N-X ₂ -NR ₃₈ R ₃₉ (5)
(R ₃₆ to R ₃₉ each independently represent an alkyl group which may have a substituent, and X ₂ represents a divalent aliphatic group which may have a substituent.)
(R ₄₀ , R ₄₁ , and R ₄₂ each independently represent an alkyl group which may have a substituent, X ₃ and X ₄ each independently represent a divalent aliphatic group which may have a substituent and which may contain an oxygen atom and/or a nitrogen atom, m and n each independently represent an integer of 1 or more, Y ₂ represents a monoalkylamino group or a dialkylamino group which may have a substituent, and any two or more of R ₄₀ , R ₄₁ , R ₄₂ , and Y ₂ may be taken together to form a ring. When there are a plurality of R ₄₀ , R ₄₁ , X ₃ , and X ₄ , they may be the same or different.)
[5] The dental curable composition according to [4], wherein the ligand containing a nitrogen atom is a compound represented by the above general formula (5).
[6] The dental hardenable composition according to any one of [1] to [5], wherein the transition metal compound (C) is a copper compound and/or a vanadium compound.
[7] The dental curable composition according to any one of [1] to [6], further comprising a polymerizable monomer having an acidic group, the content of the polymerizable monomer having an acidic group being more than 0 parts by mass and not more than 5 parts by mass per 100 parts by mass of the total amount of the polymerizable monomer components, or the dental curable composition does not contain a polymerizable monomer having an acidic group.
[8] The dental curable composition according to any one of [1] to [7], further comprising a filler (E).
[9] The dental curable composition according to any one of [1] to [8], further comprising a calcium-containing compound (F).
[10] The dental curable composition according to any one of [1] to [9], further comprising a thiourea compound (G).
[11] The dental curable composition according to any one of [1] to [10], which is a two-paste type.
[12] A composition comprising a first agent and a second agent, the first agent containing the polymerizable monomer (A) having no acidic group and a polymerization initiator (B),
The first agent and/or the second agent contains the transition metal compound (C) and the ligand compound (D),
The dental curable composition according to any one of [1] to [11], wherein none of the polymerization initiator (B), the transition metal compound (C), and the ligand compound (D) coexists in either the first agent or the second agent.
[13] The dental curable composition according to [12], wherein either the first agent or the second agent further contains a polymerizable monomer having an acidic group, and the content of the polymerizable monomer having an acidic group is more than 0 parts by mass and not more than 5 parts by mass in a total of 100 parts by mass of the polymerizable monomer components, or neither the first agent nor the second agent contains a polymerizable monomer having an acidic group.

According to the present invention, a dental hardenable composition can be provided that has excellent mechanical strength of the hardened product even when the pH is 7 or higher. Furthermore, according to the present invention, even a dental hardenable composition having a pH of 7 or higher that contains a component that imparts the effect of remineralizing dentin and promoting the healing of dental pulp tissue has excellent mechanical strength.

The dental curable composition of the present invention contains a polymerizable monomer (A) having no acidic group, a polymerization initiator (B), a transition metal compound (C), and a ligand compound (D), and the ligand compound (D) is at least one compound selected from the group consisting of a ligand containing a phosphorus atom and a ligand containing a nitrogen atom, and has a pH of 7 or more.

The mechanism by which the dental hardenable composition of the present invention exerts the effects of the present invention is unclear, but it is presumed that the ligand compound (D) coordinates to the transition metal compound (C) under conditions of pH 7 or higher, thereby improving the activity of the transition metal compound (C) and reacting with the polymerization initiator (B), resulting in excellent mechanical strength of the cured product. Each of the components contained in the dental hardenable composition of the present invention will be described below.

The dental curable composition of the present invention contains a polymerizable monomer (A) that does not have an acidic group. The polymerizable monomer (A) that does not have an acidic group is a polymerizable monomer that undergoes a radical polymerization reaction in the presence of a polymerization initiator system to become a polymer. The polymerizable monomer that constitutes the polymerizable monomer (A) that does not have an acidic group in the present invention is not limited to one type, and may be two or more types. Suitable examples of the polymerizable monomer (A) that does not have an acidic group include the following hydrophilic polymerizable monomer (A-1) and hydrophobic polymerizable monomer (A-2).

The hydrophilic polymerizable monomer (A-1) refers to a polymerizable monomer having a solubility in water of 10% by mass or more at 25° C. A polymerizable monomer having a solubility of 30% by mass or more is preferred, and a polymerizable monomer that can be dissolved in water at any ratio at 25° C. is more preferred. The hydrophilic polymerizable monomer (A-1) promotes the penetration of the components of the dental hardenable composition into the tooth structure, and also penetrates into the tooth structure itself to adhere to the organic component (collagen) in the tooth structure. Examples of the hydrophilic polymerizable monomer (A-1) include monofunctional (meth)acrylic acid ester polymerizable monomers such as 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate (hereinafter sometimes abbreviated as "HEMA"), 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,3-dihydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and 2-((meth)acryloyloxy)ethyl trimethylammonium chloride; and bifunctional (meth)acrylic acid ester polymerizable monomers such as polyethylene glycol di(meth)acrylate (having 9 or more oxyethylene groups), with 2-hydroxyethyl (meth)acrylate being preferred. In this specification, "(meth)acrylic" means acrylic and methacrylic, and the same applies to expressions such as "(meth)acryloyl" and "(meth)acrylate".

The hydrophobic polymerizable monomer (A-2) refers to a crosslinkable polymerizable monomer having a solubility in water at 25°C of less than 10% by mass. Examples of the crosslinkable polymerizable monomer (A-2) include monofunctional and bifunctional polymerizable monomers of aromatic compounds, monofunctional and bifunctional polymerizable monomers of aliphatic compounds, and trifunctional or higher polymerizable monomers. The hydrophobic polymerizable monomer (A-2) improves the mechanical strength, handleability, etc. of the dental curable composition.

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

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

Examples of the aliphatic compound-based monofunctional polymerizable monomer include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobornyl (meth)acrylate, 2-phenoxybenzyl (meth)acrylate, stearyl (meth)acrylate, dicyclopentanyl (meth)acrylate, butoxydiethylene glycol (meth)acrylate, and methoxypolyethylene glycol (meth)acrylate.
Of these, isobornyl methacrylate is preferred.

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

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

Among the polymerizable monomers (A) not having an acidic group, HEMA, Bis-GMA, D-2.6E, and TEGDMA are more preferred from the viewpoint of the adhesive strength and polymerization curing properties of the dental curable composition of the present invention.

The above-mentioned polymerizable monomer (A) not having an acidic group (hydrophilic polymerizable monomer (A-1) and hydrophobic polymerizable monomer (A-2)) may be used alone or in combination of two or more. The content of the polymerizable monomer (A) not having an acidic group is not particularly limited as long as the effects of the present invention are achieved. However, in terms of the high permeability of the composition to the tooth structure and excellent adhesion, and the cured product having sufficient mechanical strength, the content is preferably in the range of 50 to 99 parts by mass, more preferably in the range of 60 to 98 parts by mass, and even more preferably in the range of 70 to 95 parts by mass, based on the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention being 100 parts by mass. In this specification, "total amount of the polymerizable monomer components in the dental hardenable composition being 100 parts by mass" means, when the composition is packaged into the first agent and the second agent, the total amount of the polymerizable monomer contained in the first agent and the polymerizable monomer contained in the second agent is converted to 100 parts by mass.

Next, the polymerization initiator system will be described. The dental curable composition of the present invention contains a polymerization initiator (B), a transition metal compound (C), and a ligand compound (D) as the polymerization initiator system. The ligand compound (D) is at least one compound selected from the group consisting of a ligand containing a phosphorus atom and a ligand containing a nitrogen atom.

The polymerization initiator (B) of the present invention includes organic peroxides and inorganic peroxides. There are no particular limitations on these, and any known chemical polymerization initiator can be used. The organic peroxides and inorganic peroxides may each be blended alone or in combination of two or more. By blending the polymerization initiator (B), together with the transition metal compound (C) and the ligand compound (D), the dental hardenable composition has excellent hardenability and mechanical strength of the hardened product.

Typical organic peroxides include diacyl peroxides, peroxy esters, dialkyl peroxides, peroxy ketals, ketone peroxides, and hydroperoxides.

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

As peroxy esters, any known peroxy esters can be used without any restrictions as long as they have an acyl group on one side of a peroxy group (-OO- group) and a hydrocarbon group (or a group similar thereto) on the other side. Specific examples include α,α-bis(neodecanoylperoxy)diisopropylbenzene, cumyl peroxy neodecanoate, 1,1,3,3-tetramethylbutyl peroxy neodecanoate, 1-cyclohexyl-1-methylethyl peroxy neodecanoate, t-hexyl peroxy neodecanoate, t-butyl peroxy neodecanoate, t-hexyl peroxy pivalate, t-butyl peroxy pivalate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, 2,5-dimethyl-2,5-bis(2-ethylhexanoylperoxy)hexane, 1-cyclohexyl-1-methylethyl peroxy-2-ethylhexanoate, t-hexyl peroxy-2-ethylhexanoate, t-butyl peroxy-2-ethylhexanoate, t- Examples of the peroxyalkylene oxide include butyl peroxy isobutyrate, t-hexyl peroxy isopropyl monocarbonate, t-butyl peroxy maleic acid, t-butyl peroxy-3,5,5-trimethylhexanoate, t-butyl peroxy laurate, 2,5-dimethyl-2,5-bis(m-toluoylperoxy)hexane, t-butyl peroxy isopropyl monocarbonate, t-butyl peroxy-2-ethylhexyl monocarbonate, t-hexyl peroxybenzoate, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butyl peroxy acetate, t-butyl peroxy-m-toluoyl benzoate, t-butyl peroxy benzoate (hereinafter sometimes abbreviated as "BPB"), and bis(t-butylperoxy)isophthalate. Among these, from the viewpoints of storage stability and reactivity, t-butylperoxymaleic acid, t-butylperoxy-3,5,5-trimethylhexanoate, t-butylperoxybenzoate, t-butylperoxyisopropyl monocarbonate, t-butylperoxy-2-ethylhexyl monocarbonate, and t-butylperoxyacetate are preferred, with t-butylperoxybenzoate being more preferred.

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

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

Specific examples of ketone peroxides include methyl ethyl ketone peroxide, cyclohexanone peroxide, methylcyclohexanone peroxide, methyl acetoacetate peroxide, and acetylacetone peroxide.

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

Examples of the inorganic peroxide include peroxodisulfates and peroxodiphosphates. Among these, peroxodisulfates are preferred in terms of curability. Specific examples of peroxodisulfates include sodium peroxodisulfate, potassium peroxodisulfate (hereinafter sometimes abbreviated as KPS), aluminum peroxodisulfate, and ammonium peroxodisulfate.

Among the polymerization initiators (B), hydroperoxides and peroxyesters are particularly preferred. Among the hydroperoxides, t-butyl hydroperoxide, cumene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide are preferably used. Also, among the peroxyesters, t-butyl peroxybenzoate is preferably used.

The polymerization initiator (B) may be used alone or in combination of two or more. From the viewpoints of hardening property, mechanical strength, and adhesion to tooth structure, the content of the polymerization initiator (B) is preferably in the range of 0.01 to 10 parts by mass per 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention.

As the transition metal compound (C), a copper compound and/or a vanadium compound is preferably used. By coordinating the ligand compound (D) to the transition metal compound (C), the dental hardenable composition has excellent hardenability and mechanical strength of the hardened product. The transition metal compound (C) may be used alone or in an appropriate combination of two or more kinds.

Examples of copper compounds include copper(II) carboxylates, β-diketone copper(II), β-ketoester copper(II), copper alkoxides, copper dithiocarbamate, and salts of copper and inorganic acids. Examples of copper(II) carboxylates include copper(II) citrate, copper(II) acetate, copper(II) phthalate, copper(II) tartrate, copper(II) oleate, copper(II) octylate, copper(II) octenate, copper(II) naphthenate, copper(II) methacrylate, and copper(II) 4-cyclohexylbutyrate. Examples of copper(II) β-diketones include copper(II) acetylacetone, copper(II) trifluoroacetylacetone, copper(II) hexafluoroacetylacetone, copper(II) 2,2,6,6-tetramethyl-3,5-heptanedionato, and copper(II) benzoylacetone. Examples of copper(II) β-ketoesters include copper(II) ethyl acetoacetate. Examples of copper alkoxides include copper(II) methoxide, copper(II) ethoxide, copper(II) isopropoxide, copper(II) 2-(2-butoxyethoxy)ethoxide, and copper(II) 2-(2-methoxyethoxy)ethoxide. Examples of copper dithiocarbamate include copper(II) dimethyldithiocarbamate. Examples of salts of copper and inorganic acids include copper(II) nitrate, copper(II) bromide, and copper(II) chloride. These may be used alone or in appropriate combination of two or more. Among these, from the viewpoint of solubility and reactivity with respect to polymerizable monomers, copper(II) carboxylate, β-diketone copper(II), and β-ketoester copper(II) are preferred, and copper(II) acetate and copper(II) acetylacetonate are particularly preferred.

The vanadium compound is preferably a tetravalent and/or pentavalent vanadium compound. Examples of the tetravalent and/or pentavalent vanadium compounds include compounds described in JP-A-2003-96122, such as divanadium(IV) tetroxide, vanadyl acetylacetonate(IV), vanadyl oxalate(IV), vanadyl sulfate(IV), oxo-bis(1-phenyl-1,3-butanedionato)vanadium(IV), bis(maltolato)oxo-vanadium(IV), vanadium(V) pentoxide, sodium metavanadate(V), and ammonium metavanadate(V). The vanadium compounds may be used alone or in combination of two or more.

From the viewpoints of hardening, mechanical strength, and adhesion to tooth structure, the content of the transition metal compound (C) is preferably in the range of 0.0001 to 1 part by mass, more preferably in the range of 0.0005 to 0.5 parts by mass, and even more preferably in the range of 0.001 to 0.2 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention.

The dental hardenable composition of the present invention includes a ligand compound (D) capable of coordinating to a metal. The ligand compound (D) is at least one compound selected from the group consisting of a ligand containing a phosphorus atom and a ligand containing a nitrogen atom. The ligand containing a phosphorus atom includes a phosphorus atom as a coordinating atom. The ligand containing a nitrogen atom includes a nitrogen atom as a coordinating atom. One preferred embodiment includes a dental hardenable composition in which the ligand compound (D) includes a ligand containing a nitrogen atom, since the basicity of the paste of the dental hardenable composition obtained is increased and a higher pH is obtained. Another preferred embodiment includes a dental hardenable composition in which the ligand compound (D) includes a ligand containing a phosphorus atom and a ligand containing a nitrogen atom, since the basicity of the paste of the dental hardenable composition obtained is increased and a higher pH is obtained.

Examples of the ligand containing a phosphorus atom include a phosphine ligand and a phosphite ligand. Specific examples of the ligand containing a phosphorus atom include a compound represented by the following general formula (1), a compound represented by general formula (2), a compound represented by general formula (3), and a compound represented by general formula (4). The ligand containing a phosphorus atom may be used alone or in combination of two or more kinds.

(R ₁ to R ₁₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent.)

(R ₁₆ to R ₃₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and X ₁ represents a divalent aliphatic group which may have a substituent.)

(Each Ar independently represents a group represented by the following general formula (3-a).)

(Z ₁ to Z ₃ each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and at least one of Z ₁ to Z ₃ is a hydrogen atom.)

P(OY ₁ ) ₃ (4)
(Each _Y1 independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent.)

The alkyl groups of R ₁ to R ₁₅ , which may have a substituent, may be either linear or branched. The number of carbon atoms of the alkyl groups of R ₁ to R ₁₅ is not particularly limited, and is preferably 1 to 12, more preferably 1 to 6, further preferably 1 to 4, and particularly preferably 1 to 3. Examples of the alkyl groups of _{R 1} to R ₁₅ include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-
Examples of the alkyl group include a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a neopentyl group, an n-hexyl group, an isohexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an n-undecyl group, and an n-dodecyl group. The alkyl groups of R ₁ to R ₁₅ may be unsubstituted. Examples of the substituents of the alkyl groups of R ₁ to R ₁₅ include a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, an amino group, and a monoalkylamino group or a dialkylamino group having a linear or branched alkyl group having 1 to 6 carbon atoms.

Examples of the halogen atom for R ₁ to R ₁₅ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the polar group of R ₁ to R ₁₅ include an acid anhydride group, a carboxylic acid group, a carboxylic acid ester group, a carboxylic acid chloride group, a carboxylic acid amide group, a carboxylate group, a sulfonic acid group, a sulfonic acid ester group, a sulfonic acid chloride group, a sulfonic acid amide group, a sulfonate group, an aldehyde group, an epoxy group, a cyano group, an amino group, a monoalkyl-substituted amino group, a dialkyl-substituted amino group, an imide group, and an oxazoline group. From the viewpoints of curability and the mechanical strength of the cured product, the carboxylic acid group, the carboxylic acid ester group, the carboxylic acid chloride group, and the carboxylic acid amide group are preferable. , carboxylate groups, sulfonic acid groups, sulfonate groups, sulfonic acid chloride groups, sulfonate amide groups, sulfonate groups, and aldehyde groups are preferred, carboxylate groups, carboxylate groups, carboxylate chloride groups, carboxylate groups, sulfonate groups, sulfonate ester groups, sulfonate chloride groups, sulfonate groups, and aldehyde groups are more preferred, and carboxylate groups, carboxylate groups, carboxylate ester groups, carboxylate chloride groups, carboxylate groups, sulfonate groups, sulfonate ester groups, sulfonate chloride groups, and sulfonate groups are even more preferred. Examples of salts of carboxylate groups and sulfonate groups include alkali metal salts such as lithium, sodium, and potassium; and alkaline earth metal salts such as magnesium, calcium, strontium, barium, and radium. In the case of polar groups R ₁ to R ₁₅ , the number of polar groups is preferably 1 to 9, and more preferably 1 to 5.
More preferably, it is 1 to 3. When R ₁ to R ₁₅ are alkyl groups having a substituent, specific examples include a trifluoromethyl group.

The alkoxy groups of R ₁ to R ₁₅ , which may have a substituent, may be either linear or branched. The number of carbon atoms of the alkoxy groups of R ₁ to R ₁₅ is not particularly limited, but is preferably 1 to 12, more preferably 1 to 6, even more preferably 1 to 4, and particularly preferably 1 to ₃ .
Examples of the alkoxy group of R 1 to R ₁₅ include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, a sec-butoxy group, a tert-butoxy group, an n-pentyloxy group, an isopentyloxy group, a sec-pentyloxy group, a tert-pentyloxy group, a neopentyloxy group, an n-hexyloxy group, an isohexyloxy group, a sec-hexyloxy group, a tert-hexyloxy group, a neohexyloxy group, etc. Examples of the substituent of the alkoxy group of R ₁ to R ₁₅ include the same as the substituent of the alkyl group of R ₁ to R ₁₅ .

R ₁ to R ₁₅ may be the same or different, and may be, for example, a portion of R ₁ to R ₁₅ that is the same hydrogen atom, alkyl group, or alkoxy group.

The alkyl groups which may have a substituent of R ₁₆ to R ₃₅ are the same as the alkyl groups which may have a substituent of R ₁ to R _15. The alkoxy groups which may have a substituent of R ₁₆ to R ₃₅ are the same as the alkoxy groups which may have a substituent of R ₁ to R _15. The halogen atoms of R ₁₆ to R ₃₅ are the same as the halogen atoms of R ₁ to R _15. The polar groups of R ₁₆ to R ₃₅ are the same as the polar groups of R ₁ to R ₁₅ .

The divalent aliphatic group of _X1 , which may have a substituent, may be either linear or branched. The number of carbon atoms in the divalent aliphatic group is preferably 1 to 20, more preferably 1 to 16, even more preferably 1 to 12, and particularly preferably 1 to 8. Examples of the divalent aliphatic group include:
Examples of the alkylene group include an alkylene group, an alkenylene group, and an alkynylene group, and an alkylene group is preferred. Examples of the alkylene group include a methylene group, an ethylene group, a propylene group, a butylene group, a methylpropylene group, a dimethylpropylene group, a pentamethylene group, a hexamethylene group, a heptamethylene group, an octamethylene group, a nonamethylene group, a decamethylene group, an undecamethylene group, and a dodecamethylene group. Examples of the substituent of the divalent aliphatic group of X ₁ include the same as the substituent of the alkyl group of R ₁ to R ₁₅ .

In formula (3), multiple Ar may be the same or different. In the group represented by general formula (3-a), Z ₁ to Z ₃ may be the same or different. The alkyl groups which may have a substituent of _{Z 1} to Z ₃ are the same as the alkyl groups which may have a substituent of R ₁ to R _15. At least one of Z ₁ to Z ₃ may be a hydrogen atom, and all of Z ₁ to Z ₃ may be hydrogen atoms. Specific examples of Ar include the following groups.

In one embodiment, one or two of Z ₁ to Z ₃ are hydrogen atoms, and the other one or two of Z ₁ to Z ₃ may be a linear or branched alkyl group having 1 to 6 carbon atoms substituted with a halogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms substituted with a fluorine atom, or a trifluoromethyl group. The alkoxy groups which may have a substituent of Z ₁ to Z ₃ are the same as the alkoxy groups which may have a substituent of R ₁ to R _15. One preferred embodiment is a phosphine compound in which all Ar in the compound represented by the general formula (3) are 3,5-dimethylphenyl groups. Another preferred embodiment is a phosphine compound in which all Ar in the compound represented by the general formula (3) are 4-methylphenyl groups.

In the phosphite ligand represented by the general formula (4), the three Y1 _'s may be the same or different. The alkyl group which may have a substituent of _Y1 is the same as the alkyl group which may have a substituent of _R1 to _R15 . The number of carbon atoms of the aryl group which may have a substituent of _Y1 is preferably 6 to 20, more preferably 6 to 14, and even more preferably 6 to 10. Examples of the substituent of the aryl group of _Y1 include the same as the substituent of the alkyl group of _R1 to _R15 . Examples of the aryl group which may have a substituent of _Y1 include a phenyl group,
Examples of the phenyl groups include a biphenyl group, an indenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a fluorenyl group, a pyrenyl group, and a phenyl group substituted with an alkyl group such as a tolyl group, a xylyl _group , a trimethylphenyl group, an ethylphenyl group, an isopropylphenyl group, or a tetramethylphenyl group.
In another preferred embodiment, the phosphite compound includes a phosphite compound in which three Y _1s are 2,4,-di-tert-butylphenyl groups.

A preferred embodiment is a dental hardenable composition in which the ligand compound (D) is a compound represented by general formula (1).

The monodentate phosphine ligand of the above general formula (1) includes triphenylphosphine (hereinafter sometimes abbreviated as "TPP"), diphenyl(o-tolyl)phosphine, tri(o-
phosphine compounds having an electron-donating group, such as (2-fluorophenyl)diphenylphosphine, (2-chlorophenyl)diphenylphosphine, (2-bromophenyl)diphenylphosphine, (pentafluoro ... Examples of phosphine compounds having an electron-withdrawing group include phosphine compounds having an electron-withdrawing group such as bis(pentafluorophenyl)diphenylphosphine, bis(pentafluorophenyl)phenylphosphine (hereinafter sometimes abbreviated as "BPFPP"), tris(pentafluorophenyl)phosphine (hereinafter sometimes abbreviated as "TPFPP"), tris(4-fluorophenyl)phosphine (hereinafter sometimes abbreviated as "TFPP"), tris(4-chlorophenyl)phosphine, tris(4-bromophenyl)phosphine, tris(4-trifluoromethylphenyl)phosphine, tris(4-carboxyphenyl)phosphine, sodium diphenylphosphinobenzene-3-sulfonate, and trisodium triphenylphosphine-3,3',3"-trisulfonate.

Examples of the bidentate phosphine ligand of the above general formula (2) include phosphine compounds such as bis(diphenylphosphino)methane, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,5-bis(diphenylphosphino)pentane, 1,6-bis(diphenylphosphino)hexane, and 1,2-bis[bis(pentafluorophenyl)-phosphino]ethane.

Examples of the bidentate phosphine ligand of the above general formula (3) include (±)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (hereinafter sometimes abbreviated as "BINAP"), (±)-2,2'-bis(di-p-tolylphosphino)-1,1'-binaphthyl, (±)-2,2'-bis(di-p-fluorophosphino)-1,1'-binaphthyl, (±)-2,2'-bis(di-p-trifluoromethylphosphino)-1,1'-binaphthyl, (±)-2,2'-bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl, and the like.

Examples of the phosphite ligand of the above general formula (4) include trimethyl phosphite, triethyl phosphite, tris(1,1,1,3,3,3-hexafluoro-2-propyl) phosphite, triphenyl phosphite, and tris(2,4-di-t-butylphenyl) phosphite.

Examples of the nitrogen atom-containing ligand include a compound represented by general formula (5), a compound represented by general formula (6), and a multidentate ligand containing a nitrogen-containing heterocycle (7). The nitrogen atom-containing ligand may be used alone or in combination of two or more. One preferred embodiment is a dental curable composition in which the nitrogen atom-containing ligand is a compound represented by general formula (5).

R ₃₆ R ₃₇ N-X ₂ -NR ₃₈ R ₃₉ (5)
(R ₃₆ to R ₃₉ each independently represent an alkyl group which may have a substituent, and X ₂ represents a divalent aliphatic group which may have a substituent.)
(R ₄₀ , R ₄₁ , and R ₄₂ each independently represent an alkyl group which may have a substituent, X ₃ and X ₄ each independently represent a divalent aliphatic group which may have a substituent and which may contain an oxygen atom and/or a nitrogen atom, m and n each independently represent an integer of 1 or more, Y ₂ represents a monoalkylamino group or a dialkylamino group which may have a substituent, and any two or more of R ₄₀ , R ₄₁ , R ₄₂ , and Y ₂ may be taken together to form a ring. When there are a plurality of R ₄₀ , R ₄₁ , X ₃ , and X ₄ , they may be the same or different.)

The alkyl groups R ₃₆ to R ₃₉ which may have a substituent are the same as the alkyl groups R ₁ to R ₁₅ which may have a substituent.

The optionally substituted divalent aliphatic group of _X2 is the same as the optionally substituted divalent aliphatic group of _X1 .

The alkyl groups which may have a substituent of R ₄₀ , R ₄₁ , and R ₄₂ are the same as the alkyl groups which may have a substituent of R ₁ to R _15. The number of carbon atoms of the alkyl group of the monoalkylamino _group (-NHR ^a (R ^a represents an alkyl group)) and dialkylamino group (-NR ^b R ^c (R ^b and R ^c represent an alkyl group)) of Y 2 is not particularly limited, and is preferably 1 to 12, more preferably 1 to 6, still more preferably 1 to 4, and particularly preferably 1 to 3. The alkyl group of the monoalkylamino group and dialkylamino group of Y ₂ includes those which satisfy the above number of carbon atoms among the alkyl groups which may have a substituent of R ₁ to R _15. As the dialkylamino group, each alkyl group may have the above number of carbon atoms. Examples of the monoalkylamino group which may have a substituent of Y ₂ include a methylamino group, an ethylamino group, a propylamino group, an isopropylamino group, a butylamino group, an isobutylamino group, a t-butylamino group, a pentylamino group, and a hexylamino group. The dialkylamino group of _Y2 which may have a substituent includes a dimethylamino group, a diethylamino group, a dipropylamino group, a diisopropylamino group, a dibutylamino group, a diisobutylamino group, a dipentylamino group, a dihexylamino group, and an ethylmethylamino group. The alkyl group of the monoalkylamino group and the dialkylamino group of _Y2 may be substituted with a substituent. Examples of the substituent include the same as the substituent of the alkyl group of _R1 to _R15 . In a preferred embodiment, _Y2 is a dialkylamino group having two alkyl groups having 1 to 6 carbon atoms. In another preferred embodiment, in the compound represented by the general formula (6), R ₄₀ and R ₄₁ are unsubstituted alkyl groups having 1 to 3 carbon atoms, R ₄₂ is an alkyl group having 1 to 3 carbon atoms substituted with a dialkylamino group having two alkyl groups having 1 to 3 carbon atoms, Y ₂ is an alkyl group having 1 to 3 carbon atoms substituted with a dialkylamino group having two alkyl groups having 1 to 3 carbon atoms, m and n are 1, and X ₃ and X ₄ are unsubstituted alkylene groups having 1 to 3 carbon atoms.

The divalent aliphatic groups of _X3 and _X4 are similar to the divalent aliphatic groups of _X1 which may have a substituent, except that they may contain an oxygen atom and/or a nitrogen atom. _X3 and _X4 are
They may be the same or different. The number of oxygen atoms and nitrogen atoms contained in the divalent aliphatic groups of _X3 and _X4 is 1 or more, and may be 2 or more. When the divalent aliphatic groups of _X3 and _X4 contain a nitrogen atom, the divalent aliphatic groups of _X3 and _X4 may contain -NH- or ^-NRd- ( ^Rd represents an alkyl group having 1 to 6 carbon atoms).

m and n each independently represent an integer of 1 or greater, preferably an integer of 1 to 6, more preferably an integer of 1 to 5, even more preferably an integer of 1 to 3, and particularly preferably 1 or 2. m and n may be the same or different.

Any two or more of R ₄₀ , R ₄₁ , R ₄₂ and Y ₂ may be combined together to form a ring. For example, R ₄₀ , R ₄₁ or R ₄₂ may be combined with Y ₂ to form a ring.
In addition, R ₄₀ and Y ₂ , and R ₄₁ and R ₄₂ may each be joined together to form a ring, and the compound may have two rings. Furthermore, the nitrogen atom of the amino group of Y ₂ and R ₄₀ may be joined together to form a ring. The ring may contain an oxygen atom and/or a nitrogen atom. Furthermore, in another embodiment, the compound represented by general formula (6) may be a compound having a bicyclo ring. For example, in an embodiment, the compound represented by general formula (6) may be a compound having a bicyclo ring, which has a ring formed by Y ₂ and R ₄₀ together and a ring formed by R ₄₁ or R ₄₂ and Y ₂ together.

In a preferred embodiment, in the compound represented by general formula (6), R ₄₀ , R ₄₁ and R ₄₂ are linear or branched alkyl groups which may have a substituent having 1 to 6 carbon atoms.

In another preferred embodiment, the ligand compound (D) is a compound represented by the general formula (6), in which R ₄₀ , R ₄₁ and R ₄₂ each represent a linear or branched alkyl group having 1 to 6 carbon atoms which may have a substituent, and X ₃
and the divalent aliphatic group of _X4 represents an alkylene group containing no oxygen atom or nitrogen atom, m
and n each independently represent an integer of 1 or more; _Y2 represents a monoalkylamino group or a dialkylamino group which may have a substituent; and _R40 , _R41 , or _R42 and _Y2 together form a ring.

Another preferred embodiment is a dental curable composition in which the ligand compound (D) is a compound represented by general formula (6), in which R ₄₀ , R ₄₁ , and R ₄₂ each independently represent an alkyl group which may have a substituent, X ₃ and X ₄ each independently represent an alkylene group which does not contain an oxygen atom or a nitrogen atom, Y ₂ represents a monoalkylamino group or a dialkylamino group which may have a substituent, m is 1, n is 2, and the compound as a whole contains four nitrogen atoms.

The multidentate ligand (7) containing a nitrogen-containing heterocycle contains a heterocycle containing a 5- or 6-membered ring containing a nitrogen atom, has two or more nitrogen atoms in the molecule, and represents a bidentate or more ligand compound. The number of nitrogen atoms contained in the molecule of the multidentate ligand (7) is two or more, and may be three or more. The number of heterocycles contained in the multidentate ligand (7) may be one or more. Examples of the nitrogen-containing heterocycle include nitrogen-containing 5-membered rings such as pyrrole ring, pyrazole ring, and imidazole ring; nitrogen-containing 6-membered rings such as pyridine ring, pyrazine ring, pyridazine ring, piperazine ring, pyrimidine ring, and triazine ring. The nitrogen-containing heterocycle may be a condensed ring of the 5- or 6-membered ring containing the nitrogen atom and another ring (e.g., an aromatic ring), or a condensed ring of 5- or 6-membered rings containing nitrogen atoms. The condensed ring of the nitrogen atom-containing 5- or 6-membered ring and aromatic ring includes a quinoline ring, an isoquinoline ring, an indole ring, a benzimidazole ring, a benzotriazole ring, and the like. The multidentate ligand (7) may include a heterocyclic ring containing a nitrogen atom-containing 5- or 6-membered ring, and examples of the multidentate ligand include a ligand compound containing a condensed ring such as an indole ring, a benzimidazole ring, or a benzotriazole ring, and a heterocyclic ring containing a nitrogen atom-containing 5- or 6-membered ring. The multidentate ligand (7) may be bidentate or more, and may be tridentate, tetradentate, or the like.

Examples of the polydentate amine ligand of the above general formula (5) include bidentate polydentate amine compounds such as N,N,N',N'-tetramethylethylenediamine (hereinafter sometimes abbreviated as "TMEDA"), N,N,N',N'-tetramethylpropylenediamine (hereinafter sometimes abbreviated as "TMPDA"), N,N,N',N'-tetramethyl-1,4-diaminobutane, N,N,N',N'-tetraethylethylenediamine (hereinafter sometimes abbreviated as "TEEDA"), and N,N,N',N'-tetrakis(2-hydroxyethyl)ethylenediamine.

Examples of the polydentate amine ligand of the above general formula (6) include compounds having a cyclo ring such as 1,4,8,11-tetramethyl-1,4,8,11-tetraazacyclotetradecane; compounds having a bicyclo ring such as 4,11-dimethyl-1,4,8,11-tetraazabicyclohexadecane; compounds having a bicyclo ring such as 2,5,9,12-tetramethyl-2,5,9,12-tetraazatetradecane, 2,6,9,13-tetramethyl-2,6,9,13-tetraazatetradecane, 2,5,8 Examples of the amine compounds include polydentate amine compounds such as compounds having no ring, such as N,N,N,N',N'',N''-pentamethyldiethylenetriamine (hereinafter sometimes abbreviated as "PMDETA"), hexamethyltris(2-aminoethyl)amine, N,N-bis(2-dimethylaminoethyl)-N,N'-dimethylethylenediamine (hereinafter sometimes abbreviated as "HMTETA"), and tris[2-(dimethylamino)ethyl]amine (hereinafter sometimes abbreviated as "Me ₆ TREN").

The above-mentioned polydentate ligands containing a nitrogen-containing heterocycle (7) include polydentate ligands having one nitrogen-containing heterocycle, such as N-(n-propyl)pyridylmethanimine and N-(n-octyl)pyridylmethanimine; 2,2-bipyridine, 4,4'-di-(5-nonyl)-2,2'-bipyridine, N-propyl-N,N-di(2-pyridylmethyl)amine, N',N''-dimethyl-N',N''-bis((pyridin-2-yl)methyl)ethane-1,2-diamine, 2 Examples of the ligands include polydentate ligands having two or more nitrogen-containing heterocycles, such as N,6-bis(1-pyrazole)-pyridine (hereinafter sometimes abbreviated as "DPP"), 2-(2-pyridyl)benzimidazole, tris[(2-pyridyl)methyl]amine, 3,6-di(2-pyridyl)-1,2,4,5-tetrazine, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine, and 2,4,6-tri(2-pyridyl)-1,3,5-triazine.

Among these, BPFPP, TPFPP, TMEDA, TMPDA, TEEDA, PMDETA, and Me ₆ TREN are preferably used. The ligand compound (D) may be blended alone or in combination of two or more kinds. The ligand compound (D) is used to enhance the catalytic activity of the transition metal compound in the dental hardenable composition of the present invention. From the viewpoints of hardening property, mechanical strength, and adhesion to tooth structure, the content of the ligand compound (D) is preferably in the range of 0.001 to 10 parts by mass, more preferably in the range of 0.01 to 8 parts by mass, and even more preferably in the range of 1 to 6 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition of the present invention,.

When a composition that substantially contains a polymerizable monomer containing an acidic group and has a pH of less than 7 after mixing is mixed with only a pH adjuster, rather than the multidentate ligand (7) containing a nitrogen-containing heterocycle, to make the pH of the composition 7 or higher after mixing, a large amount of an inhibitor that does not contribute to promoting polymerization is added, resulting in a decrease in the mechanical strength of the cured product.

The dental hardenable composition of the present invention may further contain a filler (E) to obtain sufficient workability of the composition and sufficient X-ray opacity and mechanical strength of the cured product.

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

Examples of inorganic fillers include silica; minerals based on silica, such as kaolin, clay, mica, and mica; _{ceramics and glasses} based on silica and containing _Al2O3 , _B2O3 , _TiO2 , _ZrO2 , _{BaO, La2O3 ,} SrO, ZnO, CaO, _P2O5 , _Li2O , and _Na2O . Examples of glasses include lithium borosilicate glass, borosilicate glass, bioglass, lanthanum glass, barium glass, strontium glass, soda glass, zinc glass, and fluoroaluminosilicate glass. Examples of inorganic fillers that can be used include crystalline quartz, hydroxyapatite, alumina, titanium oxide, yttrium oxide, zirconia, barium sulfate, aluminum hydroxide, sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride. In terms of adhesiveness and ease of handling, fine particle silica having an average particle size of 0.001 to 10 μm is preferably used. Commercially available products include "Aerosil (registered trademark) OX50", "Aerosil (registered trademark) 50", "Aerosil (registered trademark) 200", "Aerosil (registered trademark) 380", "Aerosil (registered trademark) R972", "Aerosil (registered trademark) 130", and "AEROXIDE (registered trademark) Alu C" (all of which are trade names manufactured by Nippon Aerosil Co., Ltd.). In the present invention, when the inorganic filler is surface-treated as described below, the average particle size of the inorganic filler means the average particle size before the surface treatment.

Examples of organic fillers include polymethyl methacrylate, polyethyl methacrylate, polyfunctional methacrylate polymers, polyamide, polystyrene, polyvinyl chloride, chloroprene rubber, nitrile rubber, and styrene-butadiene rubber.

Examples of composite fillers made of inorganic and organic fillers include those in which inorganic fillers are dispersed in organic fillers, and inorganic/organic composite fillers in which inorganic fillers are coated with various polymers.

To improve curability, mechanical strength, and ease of handling, the filler (E) may be surface-treated with a known surface treatment agent such as a silane coupling agent before use. Examples of surface treatment agents include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. When surface treatment is performed, the average particle size refers to the average particle size of the particles before surface treatment.

The average particle size (average primary particle size) can be determined by a laser diffraction scattering method or by observing the particles under an electron microscope. 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. In the present invention, 0.1 μm is a value measured by the laser diffraction scattering method. For example, the laser diffraction scattering method can be performed by using a 0.2% sodium hexametaphosphate aqueous solution as a dispersion medium and measuring on a volume basis with a laser diffraction type particle size distribution measuring device (SALD-2300, manufactured by Shimadzu Corporation). For electron microscope observation, a scanning electron microscope (SU3800, S-4000, etc., manufactured by Hitachi High-Technologies Corporation) can be used. The electron microscope observation can be performed by taking an electron microscope photograph of the particles and measuring the particle diameters of the particles (200 or more) observed within a unit field of view of the photograph using image analysis type particle size distribution measurement software (Mac-View (Mountec Co., Ltd.)). At this time, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average primary particle diameter is calculated from the number of particles and their particle diameters.

The content of the filler (E) is not particularly limited as long as the effects of the present invention are achieved, but is preferably in the range of 50 to 300 parts by mass, and more preferably in the range of 100 to 250 parts by mass, per 100 parts by mass of the polymerizable monomer of the dental hardenable composition of the present invention. Within these ranges, the cured product will have sufficient X-ray opacity or sufficient mechanical strength, and will also have sufficient paste operability.

The dental hardenable composition of the present invention may further contain a calcium-containing compound (F). Examples of the calcium-containing compound (F) include calcium silicate and calcium salts. The calcium-containing compound (F) may be used alone or in combination of two or more. Calcium silicate is used to impart calcium ion sustained release and induce the formation of dentin-like hard tissue in exposed dental pulp. Examples of calcium silicate include tricalcium silicate, dicalcium silicate, calcium silicate hydrate, and the like. Among these, tricalcium silicate is more preferably used in terms of calcium ion sustained release. The calcium salt is used to assist the calcium ion sustained release. Examples of calcium salts that are preferably used include calcium oxide, calcium hydroxide, calcium chloride, calcium carbonate, calcium sulfate, calcium sulfite, calcium phosphate, calcium pyrophosphate, and the like. Calcium oxide and calcium hydroxide are particularly preferred because they have the ability to assist and enhance calcium ion sustained release and do not inhibit polymerization hardening.

The dental hardenable composition of the present invention may further contain a thiourea compound (G). Examples of the thiourea compound (G) include thiourea, methylthiourea, ethylthiourea, ethylenethiourea, N,N'-dimethylthiourea, N,N'-diethylthiourea, N,N'-di-n-propylthiourea, N,N'-dicyclohexylthiourea, N-acetylthiourea, N-benzoylthiourea, trimethylthiourea, triethylthiourea, tri-n-propylthiourea, tricyclohexylthiourea, tetramethylthiourea, tetraethylthiourea, tetra-n-propylthiourea, tetracyclohexylthiourea, 1-(2-pyridyl)-2-thiourea, 4,4-dimethylethylenethiourea, diphenylthiourea, N-(6-methyl-2-pyridyl)-thiourea, 1-(2-(6-ethylenethiourea), ... 1-(2-(6-methoxypyridyl))-2-thiourea, 1-(2-(6-chloropyridyl))-2-thiourea, 1-(2-(5-methylpyridyl))-2-thiourea, 1-(2-(5-ethylpyridyl))-2-thiourea, 1-(2-(5-methoxypyridyl))-2-thiourea, 1-(2-(5-chloropyridyl))-2-thiourea, 1-(2-(5-fluoropyridyl))-2-thiourea, 1-(2-(5,6-dimethylpyridyl))-2-thiourea, 4-methyl-2-imidazolidinethione, 4,4-dimethyl-2-imidazolidinethione, 4-ethyl-2-imidazolidinethione, and 4,4-diethyl-2-imidazolidinethione.

The thiourea compound (G) may be used alone or in combination of two or more kinds. From the viewpoint of hardening, the amount of the thiourea compound (G) is preferably in the range of 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the total amount of the polymerizable monomer components in the dental hardenable composition.

The dental curable composition of the present invention may further contain a polymerizable monomer having an acidic group, as long as the pH does not become less than 7. One preferred embodiment includes a dental curable composition further containing a polymerizable monomer having an acidic group, the content of the polymerizable monomer having an acidic group being more than 0 parts by mass and not more than 5 parts by mass, relative to a total amount of 100 parts by mass of the polymerizable monomer components.
Another preferred embodiment is a dental hardenable composition that does not contain a polymerizable monomer having an acidic group because the pH can be easily adjusted to 7 or more. Another preferred embodiment is a dental hardenable composition that does not substantially contain a polymerizable monomer having an acidic group because the pH can be easily adjusted to 7 or more. "Substantially does not contain a polymerizable monomer having an acidic group" means that the content of the polymerizable monomer having an acidic group is less than 1 part by mass, preferably less than 0.5 parts by mass, more preferably less than 0.1 parts by mass, and even more preferably less than 0.01 parts by mass in a total of 100 parts by mass of the polymerizable monomer components in the dental hardenable composition.

A polymerizable monomer having an acidic group is a polymerizable monomer having at least one acidic group and at least one polymerizable group such as an acryloyl group, a methacryloyl group, an acrylamide group, or a methacrylamide group. In the present invention, examples of the acidic group include a phosphate group, a phosphonic acid group, a pyrophosphate group, a thiophosphate group, a carboxylic acid group, and a sulfonic acid group. From the viewpoint of adhesion to tooth structure, it is preferable that the polymerizable monomer having an acidic group is monofunctional, having one of an acryloyl group, a methacryloyl group, an acrylamide group, or a methacrylamide group as a polymerizable group. Specific examples include the following.

Examples of polymerizable monomers having a phosphoric acid group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate. phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyeicosyl dihydrogen phosphate, 2-(meth)acryloyloxyethyl phenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl phenyl hydrogen phosphate, Monofunctional (meth)acrylate compounds having a phosphoric acid group, such as 2-(meth)acryloyloxyethyl-2-bromoethyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, and 2-(meth)acryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, their acid chlorides, alkali metal salts, ammonium salts, and amine salts; bis[2-(meth)acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, and the like. Examples of such difunctional (meth)acrylate compounds having a phosphoric acid group include phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxydecyl]hydrogen phosphate, and 1,3-di(meth)acryloyloxypropyl dihydrogen phosphate, as well as their acid chlorides, alkali metal salts, ammonium salts, and amine salts.

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

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

Examples of polymerizable monomers having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, 8-(meth)acryloyloxyoctyl dihydrogen Thiophosphate, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyeicosyl dihydrogen thiophosphate, and their acid chlorides, alkali metal salts, and ammonium salts.

Examples of polymerizable monomers having a carboxylic acid group include (meth)acrylic acid, 4-[2-[(meth)acryloyloxy]ethoxycarbonyl]phthalic acid, 4-(meth)acryloyloxyethyltrimellitic acid, 4-(meth)acryloyloxybutyloxycarbonylphthalic acid, 4-(meth)acryloyloxyhexyloxycarbonylphthalic acid, 4-(meth)acryloyloxyoctyloxycarbonylphthalic acid, 4-(meth)acryloyloxydecyloxy dicarbonylphthalic acid and their acid anhydrides; 5-(meth)acryloylaminopentylcarboxylic acid, 6-(meth)acryloyloxy-1,1-hexanedicarboxylic acid, 8-(meth)acryloyloxy-1,1-octanedicarboxylic acid, 10-(meth)acryloyloxy-1,1-decanedicarboxylic acid, 11-(meth)acryloyloxy-1,1-undecanedicarboxylic acid, their acid chlorides, alkali metal salts, ammonium salts, and amine salts.

Examples of polymerizable monomers having a sulfonic acid group include 2-(meth)acrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl (meth)acrylate, and acid chlorides, alkali metal salts, ammonium salts, and amine salts thereof.

Among the above-mentioned polymerizable monomers having an acidic group, those having a phosphate group, those having a pyrophosphate group, and those having a carboxylic acid group are preferred because they exhibit superior adhesion to tooth structure, and in particular, those having a phosphate group and those having a carboxylic acid group are preferred _.
More preferred are (meth)acrylate-based monofunctional polymerizable monomers having a phosphoric acid group with a _C20 alkyl group or a _C6 - _C20 alkylene group, or (meth)acrylate-based polymerizable monomers having a carboxylic acid group, and even more preferred are (meth)acrylate-based monofunctional polymerizable monomers having a phosphoric acid group with a _C8 - _C12 alkylene group as the main chain in the molecule. Also preferred are 10-methacryloyloxydecyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitic acid and 4-(meth)acryloyloxyethyl trimellitic anhydride, and most preferred is 10-methacryloyloxydecyl dihydrogen phosphate.

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

Photopolymerization initiator systems include α-diketones, ketals, thioxanthones, (bis)acylphosphine oxides, and α-aminoacetophenones.

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

Examples of ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

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

Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, benzoylbis(2,6-dimethylphenyl)phosphine oxide, water-soluble acylphosphine oxide compounds disclosed in JP-B-3-57916, and salts thereof (e.g., sodium salt, potassium salt, ammonium salt), etc. Examples of bisacylphosphine oxides include bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, dibenzoylphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, tris(2,4-dimethylbenzoyl)phosphine oxide, tris(2-methoxybenzoyl)phosphine oxide, and salts thereof (e.g., sodium salts, potassium salts, ammonium salts), and the like. Among these (bis)acylphosphine oxides, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and 2,4,6-trimethylbenzoylphenylphosphine oxide sodium salt are preferred.

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

In addition, in the dental hardenable composition of the present invention, in order to enhance the photocurability, a photopolymerization initiator and a polymerization accelerator for the photopolymerization initiator may be used in combination. Furthermore, the polymerization initiator (B) may be used in combination with a polymerization accelerator. Examples of the polymerization accelerator used together with the polymerization initiator (B) and/or the photopolymerization initiator include tertiary amines, aldehydes, thiol compounds, triazine compounds substituted with a trihalomethyl group, sulfinic acids, benzotriazole compounds, benzimidazole compounds, sulfites, hydrogen sulfites, borate compounds, barbituric acid compounds, etc. The polymerization accelerator may be used alone or in combination of two or more types.

Examples of tertiary amines include 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, and 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) aromatic tertiary amines such as N-methyldiethanolamine, trimethylamine, triethylamine, N-methyldiethanol ... Examples of such tertiary amines include aliphatic amines such as ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, triethanolamine, 2-(dimethylamino)ethyl(meth)acrylate, N-methyldiethanolamine di(meth)acrylate, N-ethyldiethanolamine di(meth)acrylate, triethanolamine mono(meth)acrylate, triethanolamine di(meth)acrylate, and triethanolamine tri(meth)acrylate.

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

Examples of sulfinic acids include p-toluenesulfinic acid, sodium p-toluenesulfinate, potassium p-toluenesulfinate, lithium p-toluenesulfinate, calcium p-toluenesulfinate, benzenesulfinic acid, sodium benzenesulfinate, potassium benzenesulfinate, lithium benzenesulfinate, calcium benzenesulfinate, 2,4,6-trimethylbenzenesulfinic acid, sodium 2,4,6-trimethylbenzenesulfinate, potassium 2,4,6-trimethylbenzenesulfinate, lithium 2,4,6-trimethylbenzenesulfinate, and 2,4,6-trimethylbenzenesulfinate. Examples of the sulfinate include calcium sulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate, potassium 2,4,6-triethylbenzenesulfinate, lithium 2,4,6-triethylbenzenesulfinate, calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, calcium 2,4,6-triisopropylbenzenesulfinate, etc. Among these, sodium benzenesulfinate, sodium p-toluenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, and sodium 2,4,6-triisopropylbenzenesulfinate are particularly preferred.

Examples of benzotriazole compounds include 1H-benzotriazole (hereinafter sometimes abbreviated as "BTA"), 5-methyl-1H-benzotriazole, 5,6-dimethyl-1H-benzotriazole, etc. Examples of benzimidazole compounds include benzimidazole, 5-methylbenzimidazole, 5,6-dimethylbenzimidazole, etc. Examples of sulfites include sodium sulfite, potassium sulfite, calcium sulfite, ammonium sulfite, etc. Examples of hydrogen sulfites include sodium hydrogen sulfite, potassium hydrogen sulfite, etc. Examples of borate compounds include aryl borate compounds having 1 to 4 aryl groups in one molecule (e.g., tetraphenyl boron, tetrakis (p-chlorophenyl) boron, etc.) and salts thereof. Examples of barbituric acid compounds include barbituric acid, 5-butylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and salts thereof.

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

In addition, the dental curable composition of the present invention may contain a polymerization inhibitor, a pH adjuster, an ultraviolet absorber, an organic solvent, a solvent such as water, a thickener, a colorant, an antibacterial agent, a fragrance, etc., within a range that does not inhibit the effects of the present invention. These may be used alone or in combination of two or more. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, dibutyl hydroquinone, dibutyl hydroquinone monomethyl ether, t-butyl catechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, and 2,6-di-t-butyl-4-methylphenol. The content of the polymerization inhibitor is preferably 0.001 to 1.0 parts by mass relative to 100 parts by mass of the total amount of the polymerizable monomers in the dental curable composition. Examples of the pH adjuster include tertiary amines (e.g., N-methyldiethanolamine, triethanolamine, etc.) exemplified as polymerization promoters for photopolymerization initiators. In some embodiments, the content of the solvent (e.g., water, organic solvent) in the dental hardenable composition is preferably less than 1 mass%, more preferably less than 0.1 mass%, and even more preferably less than 0.01 mass%, based on the total mass of the dental hardenable composition. In other embodiments, the dental hardenable composition is preferably substantially free of water from the viewpoint of achieving the effects of the present invention. The dental hardenable composition being substantially free of water means that the content of water is preferably 1 mass% or less, more preferably 0.1 mass% or less, and even more preferably 0.01 mass% or less, based on the total mass of the dental hardenable composition, and may be 0 mass%.

The dental hardenable composition of the present invention may be prepared according to a conventional method depending on the components. The dental hardenable composition of the present invention is used in a two-part form, which may be appropriately selected from a powder and liquid form, a paste and liquid form, a two-paste form, etc., but in a more preferred embodiment from the viewpoint of operability, it is used in a two-paste form. It is preferable to store each paste in a state where the pastes are isolated from each other, and to knead the two pastes just before use and harden them by promoting chemical polymerization. The paste is usually prepared by kneading a liquid component prepared by mixing components other than the filler (E) with the filler (E) (powder).

The two-paste dental hardenable composition of the present invention is packaged in a first agent and a second agent, and the first agent contains the polymerizable monomer (A) having no acidic group and the polymerization initiator (B), and the first agent and/or the second agent contains a transition metal compound (C) and a ligand compound (D), and it is preferable that the polymerization initiator (B), the transition metal compound (C), and the ligand compound (D) do not coexist in either the first agent or the second agent. As a preferred embodiment, either the first agent or the second agent further contains a polymerizable monomer having an acidic group, and the content of the polymerizable monomer having an acidic group is more than 0 parts by mass and 5 parts by mass or less in a total amount of 100 parts by mass of the polymerizable monomer component, or neither the first agent nor the second agent contains a polymerizable monomer having an acidic group. As another preferred embodiment, the two-paste dental hardenable composition is one in which the first agent and the second agent do not substantially contain a polymerizable monomer having an acidic group.

The dental hardenable composition of the present invention is used for bonding dental prostheses such as crowns, inlays, and bridges to tooth structure in damaged areas of teeth, and for building abutments. It is particularly suitable for use as a dental resin cement.

The present invention includes embodiments that combine the above configurations in various ways within the scope of the technical concept of the present invention, as long as the effects of the present invention are achieved.

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

[Polymerizable monomer having an acidic group]
MDP: 10-methacryloyloxydecyl dihydrogen phosphate

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

[Polymerization initiator (B)]
THP: 1,1,3,3-tetramethylbutyl hydroperoxide BPB: t-butyl peroxybenzoate

[Inorganic peroxide]
KPS: Potassium peroxodisulfate

[Transition metal compound (C)]
CuA: Copper (II) acetate
VOAA: Vanadyl acetylacetonate (IV)

[Ligand compound (D)]
BPFPP: bis(pentafluorophenyl)phenylphosphine TPFPP: tris(pentafluorophenyl)phosphine PPh ₃ : triphenylphosphine TEEDA: tetraethylethylenediamine TMPDA: tetramethylpropylenediamine

[Filler (E)]
Surface-treated Ba glass powder:
Barium glass (manufactured by Estec Co., Ltd., product code "E-3000") was pulverized in a ball mill to obtain barium glass powder. The average particle size of the obtained barium glass powder was measured on a volume basis using a laser diffraction type particle size distribution measuring device (manufactured by Shimadzu Corporation, model "SALD-2300") and found to be 2.4 μm. 100 parts by mass of this barium glass powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method to obtain a surface-treated Ba glass powder.
R972: Fine particle silica manufactured by Nippon Aerosil Co., Ltd., trade name "Aerosil (registered trademark) R972", average particle size: 16 nm
Alumina: Aluminum oxide, manufactured by Nippon Aerosil Co., Ltd., trade name "AEROXIDE (registered trademark) Alu C", average particle size: 20 nm

[Calcium-containing compound (F)]
_Tricalcium silicate: _Ca3SiO5
Calcium oxide: CaO

[Thiourea Compound (G)]
PyTU: 1-(2-pyridyl)-2-thiourea 6MPyTU: N-(6-methyl-2-pyridyl)-thiourea 5FPyTU: 1-(2-(5-fluoropyridyl))-2-thiourea

[pH adjuster]
TTA: Triethanolamine

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

[Polymerization accelerator]
DEPT: N,N-bis(2-hydroxyethyl)-p-toluidine TPSS: 2,4,6-triisopropylbenzenesulfinic acid Sodium sulfite: Na ₂ SO ₃
BTA: 1H-benzotriazole

(Examples 1 to 15 and Comparative Examples 1 to 5)
The dental curable compositions of Examples 1 to 15 and Comparative Examples 1 to 5 were prepared by mixing the components other than the filler among the components shown in Tables 1 and 2 at room temperature to obtain a uniform liquid component, and then kneading the obtained liquid component with the filler. Next, the pH of the paste after kneading, and the bending strength and bending modulus of the cured product were measured using these dental curable compositions according to the methods described below. Tables 1 and 2 show the compounding ratios (parts by mass) and test results of the dental curable compositions.

[pH of paste after mixing]
The first and second parts of the dental hardenable composition of the present invention were mixed and applied to a moistened pH test paper (Universal Indicator Paper pH 1-14), and the pH of the paste after mixing was visually observed. If it is difficult to determine whether the pH is 7 or more, Johnson Test Papers Comparator Paper pH 6.4-8.0 pH Paper may be used for measurement. The average value of the results of three pH measurements of the paste was taken as the pH of the paste after mixing.

[Flexural strength and flexural modulus of the cured product of the dental curable composition upon chemical curing]
A polyester film was laid on a glass slide, and a stainless steel mold of 2 mm length x 25 mm width x 2 mm depth was placed on the polyester film. The mold was then filled with a mixture of the first and second agents of the dental hardenable composition of the present invention, and the surface of the composition in the mold was pressed against the glass slide via the polyester film, and the two glass slides were fixed using a double clip with a width of 25 mm. The sample fixed with the double clip was left to stand in a 37°C incubator for 1 hour to polymerize and harden, and then the sample was removed from the incubator and the polymerized and hardened product of the composition was removed from the mold. The polymerized and hardened product was immersed in distilled water at 37°C for 24 hours and stored, and then a bending test was performed using this as a test piece. The bending strength was measured by a three-point bending test using a universal testing machine (Shimadzu Corporation, Autograph "AG-I 100kN") with a span of 20 mm between supports and a crosshead speed of 1 mm/min. The average bending strength of the five test pieces was taken as the bending strength of the test piece. The average value of the flexural modulus of the five test pieces was regarded as the flexural modulus of the test piece.

As shown in Tables 1 and 2, the dental hardenable compositions of the present invention (Examples 1 to 15) had excellent results, with the bending strength of the hardened product being 80 MPa or more and the bending modulus of elasticity being 5.0 GPa or more when the pH of the paste after mixing was 7 or more. In particular, the dental hardenable composition shown in Example 15, which contains a calcium-containing compound (F) component that imparts the effect of remineralizing dentin and promoting the healing of dental pulp tissue, also had excellent results, with a bending strength of 80 MPa and a bending modulus of elasticity of 5.0 GPa. In Comparative Examples 1 to 3, the paste pH after mixing was 7 or more, but the bending strength was very low or the composition was not hardened. In Comparative Examples 4 and 5, the bending strength was 80 MPa or more, but the pH of the paste after mixing was less than 7, and this was the performance obtained by the polymerization initiator system in the composition functioning. When the pH after mixing of Comparative Examples 4 and 5 was 7 or more, the hardening property decreased, so data similar to that obtained when the pH was less than 7 was not obtained.

The dental hardenable composition of the present invention can be suitably used in dental treatment for bonding dental prostheses such as crowns, inlays, and bridges to tooth structure, and for constructing abutments.

Claims (13)

Contains a polymerizable monomer (A) having no acidic group and a polymerization initiator system,
Does not contain ascorbic acid
The polymerization initiator system contains a polymerization initiator (B), a transition metal compound (C), and a ligand compound (D),
the transition metal compound (C) is a copper compound and/or a vanadium compound,
the ligand compound (D) is at least one compound selected from the group consisting of a ligand containing a phosphorus atom and a ligand containing a nitrogen atom,
the phosphorus atom-containing ligand is at least one compound selected from the group consisting of a compound represented by the following general formula (1), a compound represented by the general formula (2), a compound represented by the general formula (3), and a compound represented by the general formula (4),
(R ₁ to R ₁₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent.)
(R ₁₆ to R ₃₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and X ₁ represents a divalent aliphatic group which may have a substituent.)
(Each Ar independently represents a group represented by the following general formula (3-a).)
(Z ₁ to Z ₃ each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and at least one of Z ₁ to Z ₃ is a hydrogen atom.)
P(OY ₁ ) ₃ (4)
(Each Y1 _{independently} represents an alkyl group which may have a substituent, or an aryl group which may have a substituent.)
the nitrogen atom-containing ligand is at least one compound selected from the group consisting of a compound represented by general formula (5), a compound represented by general formula (6), and a multidentate ligand containing a nitrogen-containing heterocycle (7),
the polydentate ligand (7) is a bidentate or higher ligand compound that contains a nitrogen atom-containing 5- or 6-membered heterocycle and has two or more nitrogen atoms in the molecule;
A dental hardenable composition having a pH of 7 or greater.
R ₃₆ R ₃₇ N-X ₂ -NR ₃₈ R ₃₉ (5)
(R ₃₆ to R ₃₉ each independently represent an alkyl group which may have a substituent, and X ₂ represents a divalent aliphatic group which may have a substituent.)
(R ₄₀ , R ₄₁ , and R ₄₂ each independently represent an alkyl group which may have a substituent, X ₃ and X ₄ each independently represent a divalent aliphatic group which may have a substituent and which may contain an oxygen atom and/or a nitrogen atom, m and n each independently represent an integer of 1 or more, Y ₂ represents a monoalkylamino group or a dialkylamino group which may have a substituent, and any two or more of R ₄₀ , R ₄₁ , R ₄₂ , and Y ₂ may be taken together to form a ring. When there are a plurality of R ₄₀ , R ₄₁ , X ₃ , and X ₄ , they may be the same or different.) The ligand compound (D) is a ligand containing a phosphorus atom,
The dental hardenable composition according to claim 1, wherein the ligand containing a phosphorus atom is at least one compound selected from the group consisting of a compound represented by the following general formula (1), a compound represented by the general formula (2), a compound represented by the general formula (3), and a compound represented by the general formula (4).
(R ₁ to R ₁₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent.)
(R ₁₆ to R ₃₅ each independently represent a hydrogen atom, a halogen atom, a polar group, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and X ₁ represents a divalent aliphatic group which may have a substituent.)
(Each Ar independently represents a group represented by the following general formula (3-a).)
(Z ₁ to Z ₃ each independently represent a hydrogen atom, a halogen atom, an alkyl group which may have a substituent, or an alkoxy group which may have a substituent, and at least one of Z ₁ to Z ₃ is a hydrogen atom.)
P(OY ₁ ) ₃ (4)
(Each _Y1 independently represents an alkyl group which may have a substituent, or an aryl group which may have a substituent.) The dental hardenable composition according to claim 1 , wherein the ligand containing a phosphorus atom is a compound represented by general formula (1): The ligand compound (D) is a ligand containing a nitrogen atom,
the nitrogen atom-containing ligand is at least one compound selected from the group consisting of a compound represented by general formula (5), a compound represented by general formula (6), and a multidentate ligand containing a nitrogen-containing heterocycle (7),
The dental hardenable composition according to claim 1, wherein the polydentate ligand (7) is a bidentate or higher ligand compound that contains a heterocycle containing a nitrogen atom and has two or more nitrogen atoms in the molecule.
R ₃₆ R ₃₇ N-X ₂ -NR ₃₈ R ₃₉ (5)
(R ₃₆ to R ₃₉ each independently represent an alkyl group which may have a substituent, and X ₂ represents a divalent aliphatic group which may have a substituent.)
(R ₄₀ , R ₄₁ , and R ₄₂ each independently represent an alkyl group which may have a substituent, X ₃ and X ₄ each independently represent a divalent aliphatic group which may have a substituent and which may contain an oxygen atom and/or a nitrogen atom, m and n each independently represent an integer of 1 or more, Y ₂ represents a monoalkylamino group or a dialkylamino group which may have a substituent, and any two or more of R ₄₀ , R ₄₁ , R ₄₂ , and Y ₂ may be taken together to form a ring. When there are a plurality of R ₄₀ , R ₄₁ , X ₃ , and X ₄ , they may be the same or different.) 2. The dental hardenable composition according to claim 1 , wherein the ligand containing a nitrogen atom is a compound represented by the above general formula (5). the copper compound is at least one selected from the group consisting of copper(II) carboxylate , copper(II) β-diketone, copper(II) β-ketoester, copper alkoxide, copper dithiocarbamate, and a salt of copper and an inorganic acid;
6. The dental hardenable composition according to claim 1 , wherein the vanadium compound is a IV and/or V vanadium compound . The dental curable composition according to any one of claims 1 to 6, further comprising a polymerizable monomer having an acidic group, the content of the polymerizable monomer having an acidic group being more than 0 parts by mass and not more than 5 parts by mass per 100 parts by mass of the total amount of the polymerizable monomer components, or the dental curable composition does not contain a polymerizable monomer having an acidic group. The dental hardenable composition according to any one of claims 1 to 7, further comprising a filler (E). The dental hardenable composition according to any one of claims 1 to 8, further comprising a calcium-containing compound (F). The dental hardenable composition according to any one of claims 1 to 9, further comprising a thiourea compound (G). The dental hardenable composition according to any one of claims 1 to 10, which is of a two-paste type. The composition is divided into a first agent and a second agent, the first agent containing the polymerizable monomer (A) having no acidic group and a polymerization initiator (B),
The first agent and/or the second agent contains the transition metal compound (C) and the ligand compound (D),
The dental hardenable composition according to any one of claims 1 to 11, wherein none of the polymerization initiator (B), the transition metal compound (C), and the ligand compound (D) coexists in either the first agent or the second agent. The dental curable composition according to claim 12, wherein either the first agent or the second agent further contains a polymerizable monomer having an acidic group, and the content of the polymerizable monomer having an acidic group is more than 0 parts by mass and not more than 5 parts by mass in a total amount of 100 parts by mass of the polymerizable monomer components, or neither the first agent nor the second agent contains a polymerizable monomer having an acidic group.