Dental adhesive composition

Abstract

A dental adhesive composition containing: a polymerizable monomer (A) that has an acidic group; and a photoredox catalyst (B) that has a singlet excited state reduction potential ES1 red of 1.5 V vs. SCE or greater.

Description

Dental adhesive composition

[0001] The present invention relates to a dental adhesive composition.

[0002] Filling and restorative materials such as filling composite resins and crown restorative materials such as metal alloys, ceramics, and resin materials are widely used for restoring missing tooth tissue damaged by caries, fractures, etc. Dental bonding materials are mainly used to bond filling and restorative materials to tooth tissue, and dental cements are mainly used to bond crown restorative materials to tooth tissue. In recent years, dental self-adhesive composite resins, which combine the functions of filling and restorative materials and dental bonding materials, have also been used. Resin-based compositions consisting of polymerizable monomers, polymerization initiators, fillers, etc. are commonly used as dental adhesive compositions such as dental bonding materials, dental cements, and dental self-adhesive composite resins that have adhesive properties to tooth tissue.

[0003] Among dental adhesive compositions, dental bonding materials are generally liquid polymerizable monomer-containing compositions in which polymerizable monomers, polymerization initiators, stabilizers, etc. are dissolved. On the other hand, dental self-adhesive resin cements and dental self-adhesive composite resins are both paste-like compositions, and are generally produced by mixing a liquid polymerizable monomer-containing composition in which polymerizable monomers, polymerization initiators, stabilizers, etc. are dissolved with a powdered filler, etc. Dental adhesive compositions are provided to dentists, who are users, in a container, and are required to maintain a certain level of performance within their expiration date.

[0004] (Meth)acrylates are generally used as polymerizable monomers contained in dental bonding materials, dental self-adhesive resin cements, and dental self-adhesive composite resin materials. As will be explained below, dental bonding materials, dental self-adhesive resin cements, and dental self-adhesive composite resins contain polymerizable monomers having acidic groups such as phosphate groups or carboxyl groups to impart adhesiveness to tooth structures or prostheses.

[0005] Conventionally, adhesive systems using dental bonding materials have been commonly used, such as acid-etching (total-etching) systems, in which the surface of the tooth is etched using an acid etching agent such as a phosphoric acid solution, followed by application of an adhesive bonding agent, and then application of a dental restorative material thereon, thereby bonding the tooth and the dental restorative material. On the other hand, there are also so-called self-etching adhesive systems, which do not use acid etching agents. Conventionally, two-step adhesive systems have been mainstream for this type of adhesive system, in which a self-etching primer containing an acidic monomer, a hydrophilic monomer, and water is applied to the surface of the tooth, and then a bonding agent containing a cross-linking monomer and a polymerization initiator is applied without rinsing with water. However, recently, one-step adhesive systems using one-component dental bonding materials (one-component dental bonding materials) that combine the functions of both a self-etching primer and a bonding agent have become more common. One-component dental bonding materials generally contain acidic monomers, hydrophilic monomers, cross-linking monomers, etc. as monomer components.

[0006] The above-mentioned restorative method uses two materials: a dental bonding material and a dental filling and restorative material (dental filling composite resin). In recent years, however, dental self-adhesive composite resins, which are dental filling composite resins with adhesive properties, have been developed and are beginning to be put into practical use as materials that eliminate the use of dental bonding materials and reduce the number of operational steps in restorative treatment. In addition to the components of conventional dental filling composite resins, such as a polyfunctional polymerizable monomer and filler to impart mechanical strength and a polymerization initiator to improve curing, dental self-adhesive composite resins contain a polymerizable monomer with an acidic group, which has traditionally been used in dental bonding materials, to impart adhesion to tooth structure.

[0007] Traditionally, dental resin cements have typically used a pretreatment agent (primer or bonding agent) and a two-paste dental resin cement. This system is called a pretreatment-combined dental resin cement. With a pretreatment-combined dental resin cement, prior to bonding the crown material to the tooth, a pretreatment agent containing an adhesive monomer is used to simultaneously remove the smear layer from the tooth surface and allow the monomer to penetrate the collagen layer. The dental resin cement is then cured to bond the monomer-permeated tooth and the prosthesis. In recent years, there has been a demand for simplified dental treatment procedures to expedite dental treatment and reduce the burden on patients. Cements that can bond tooth and prosthesis without a pretreatment agent, i.e., dental self-adhesive resin cements that can perform demineralization, penetration, and curing all at once, have become popular.

[0008] In all of the above dental adhesive compositions, it is desired to improve the adhesiveness to tooth tissue, particularly dentin. The functions required for a dental adhesive composition to obtain adhesive strength to dentin include a "decalcification action" in which the dentin surface is dissolved with an acidic component, a "penetration action" in which a monomer component penetrates the collagen layer of dentin, and a "hardening action" in which the penetrated monomer component hardens to form a hybrid layer with collagen (hereinafter referred to as a resin-impregnated layer). Among these factors, enhancing the hardening property of the resin-impregnated layer is extremely important for improving adhesiveness.

[0009] Photopolymerization initiators capable of polymerizing and curing under light such as visible light, and redox-type chemical polymerization initiators consisting of an oxidizing agent and a reducing agent, etc., are sometimes used as polymerization initiators for curing these dental adhesive compositions. Photopolymerization initiators can also be used in one-component and one-material compositions, and after application, the composition can be polymerized and cured by irradiating it with light such as blue light using a dental irradiator, resulting in adhesion. When adhering a dental filling and restorative material using a dental bonding material, light irradiation of the dental bonding material and the dental filling and restorative material enables adhesion to tooth structure. Meanwhile, chemical polymerization initiators, i.e., oxidizing agents and reducing agents, must be packaged separately, for example, as a first agent containing an oxidizing agent and a second agent containing a reducing agent, and are provided to dentists as a dental adhesive composition in a packaged form. The dentist must mix the first and second agents immediately before use, which generates radicals through a redox reaction, allowing the polymerization and curing of the dental adhesive composition to proceed even in areas where light cannot reach, thereby adhering the dental crown restorative material, etc., to tooth structure.

[0010] Patent Document 1 discloses a dental bonding material. Patent Document 2 discloses a dental self-adhesive resin cement. Patent Document 3 discloses polymerization initiator technology for dental self-adhesive composite resins. Patent Document 1 relates to an invention in which the use of a bisacylphosphine oxide-based polymerization initiator in a dental bonding material can improve the polymerization curing properties of a resin-impregnated layer, thereby achieving high adhesive strength. Patent Document 2 discloses a chemical polymerization initiator system effective in improving the adhesive strength of dental self-adhesive resin cements to tooth tissue. Patent Document 3 discloses a dental self-adhesive composite resin having an initiator system consisting of a persulfate, a transition metal, and a photoinitiator.

[0011] International Publication No. WO 2008 / 087981 International Publication No. WO 2010 / 106903 International Publication No. WO 2013 / 082337

[0012] As a result of the inventors' investigations, the polymerization initiator technology disclosed in Patent Document 1 certainly enhances the polymerization and curing properties of dental bonding materials, but there is room for improvement in the bond strength to tooth tissue for one-component dental bonding materials. Furthermore, the chemical polymerization initiator technology for dental adhesive compositions disclosed in Patent Document 2 is effective in improving bond strength to tooth tissue without light exposure, but has not been studied for improving bond strength with light exposure. However, in recent years, the aesthetic value of dental crown materials has increased, and light-transmitting prosthetic appliances have become more common. In response to these changes in the market environment for dental crown materials, there has been an increasing demand for photopolymerization methods in addition to the traditionally mainstream chemical polymerization method for hardening dental resin cements. Therefore, it is necessary to consider ways to improve the bond strength of dental resin cements using photopolymerization. While the technology disclosed in Patent Document 3 demonstrates bond strength to tooth tissue for dental self-adhesive composite resins, the bond strength is not as strong as that achieved when a bonding agent is used in combination, leaving room for further improvement. Furthermore, dental adhesive compositions are required to maintain high adhesion to tooth tissue even after storage in addition to adhesive strength. An object of the present invention is to provide a dental adhesive composition that not only has excellent adhesion to tooth tissue when photocured, but also maintains high adhesion to tooth tissue even after storage.

[0013] The present inventors have conducted extensive research into dental adhesive compositions that have excellent adhesion to tooth tissue when photocured and that exhibit little deterioration in performance during long-term storage. As a result, it has been found that a dental adhesive composition having a singlet excited reduction potential E Ｓ１ ｒｅｄ The present inventors have found that dental adhesive compositions containing a photoredox catalyst that satisfies the above requirements exhibit specifically high adhesive strength to tooth tissue and maintain high adhesion to tooth tissue even after storage, and have completed the present invention after further investigation.

[0014] That is, the present invention includes the following inventions: [1] A polymerizable monomer (A) having an acidic group, and a singlet excited state reduction potential E Ｓ１ ｒｅｄ[2] A dental adhesive composition containing a photoredox catalyst (B) having a singlet excited oxidation potential E of 1.5 V vs. SCE or more. Ｓ１ оｘ [3] The dental adhesive composition according to the above [1] or [2], wherein the photoredox catalyst (B) is at least one selected from the group consisting of compounds represented by the following formulas (1), (2), and (3):

[0015] (In formula (1), R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ and R ９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom; － is BF ４ － , P.F. ６ － , ClO ４ － or HSO ４ － It is.)

[0016] (In formula (2), R １１ , R １３ , R １４ , R １５ , R １６ , and R １８ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R １２ , R １７ , and R １９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms; － is BF ４ － , P.F. ６ － , ClO ４ － or HSO ４ － It is.)

[0017] (In formula (3), R ２１ , R ２２ , R ２３ and R ２４ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a carboxylic acid group or an ester thereof having 1 to 10 carbon atoms, a hydroxyl group, a cyano group, or a halogen atom.

[0018] [4] R in the formula (1) １ , R ２ and R ３ [5] The dental adhesive composition according to the above [3], wherein R in the formula (1) is independently an alkyl group having 1 to 4 carbon atoms. １ , R ２ and R ３are each independently a methyl group, an isopropyl group, or a t-butyl group. [6] The dental adhesive composition according to any one of the above [1] to [5], wherein the absorption spectrum of the photoredox catalyst (B) includes the range of 400 nm to 500 nm. [7] The dental adhesive composition according to any one of the above [1] to [6], further comprising a polymerizable monomer (C) having no acidic group. [8] The dental adhesive composition according to any one of the above [1] to [7], further comprising an organic peroxide (D). [9] The dental adhesive composition according to any one of the above [1] to [8], further comprising a reducing agent (E).

[10] The dental adhesive composition according to any one of the above [1] to [9], further comprising a phosphine compound (F) having an electron-withdrawing group.

[11] The dental adhesive composition according to any one of the above [1] to

[10] , further comprising a photopolymerization initiator (G).

[12] The dental adhesive composition according to any one of the above [1] to

[11] , which is a one-component dental bonding material.

[13] The dental adhesive composition according to any one of the above [1] to

[11] , which is a dental self-adhesive composite resin.

[14] The dental adhesive composition according to any one of the above [1] to

[11] , which is a dental self-adhesive resin cement.

[15] The dental adhesive composition according to any one of the above [1] to

[11] , which is a kit comprising a one-component dental bonding material containing the photoredox catalyst (B) and a two-paste dental composition.

[16] The dental adhesive composition according to any one of the above [1] to

[11] , which is a kit comprising a one-component dental bonding material containing the photoredox catalyst (B) and a one-paste dental composition.

[0019] According to the present invention, it is possible to provide a dental adhesive composition that has excellent adhesiveness to tooth tissue when photocured and that maintains high adhesiveness to tooth tissue even after storage.

[0020] The present invention will be described in detail below using embodiments. In this specification, the upper and lower limits of numerical ranges (such as the content of each component, values ​​calculated from each component, and physical properties) can be combined as appropriate. That is, in this specification, the lower and upper limits described in stages for numerical ranges can be independently combined. For example, a description of the same item, "preferably 10 to 90, more preferably 30 to 60," can be combined with the "preferable lower limit (10)" and the "more preferable upper limit (60)" to form "10 to 60." Furthermore, for a numerical range, for example, based on a description of "preferably 10 to 90, more preferably 30 to 60," the upper limit can be specified as "10 or more" or "30 or more" without specifying a specific upper limit. Similarly, the upper limit can be specified as "90 or less" or "60 or less" without specifying a specific lower limit. Unless otherwise specified, a numerical range simply described as "10 to 90" represents a range of 10 to 90. As described above, for example, from the description of "preferably 10 or more, more preferably 30 or more" and the description of "preferably 90 or less, more preferably 60 or less" for the same item, the "preferable lower limit (10)" and the "more preferable upper limit (60)" can be combined to form "10 or more and 60 or less." Similarly, as described above, the lower limit alone can be specified as "10 or more" or "30 or more," and similarly, the upper limit alone can be specified as "90 or less" or "60 or less." The term "(meth)acryloyl group" refers to both acryloyl and methacryloyl groups. The same applies to similar terms. In this specification, "storage stability" means that high adhesion to tooth tissue is maintained even after storage. Therefore, even if adhesion decreases due to long-term storage, if high adhesion is still maintained, "storage stability" can be said to be high.

[0021] The dental adhesive composition of the present invention comprises a polymerizable monomer (A) having an acidic group and a singlet excited reduction potential E Ｓ１ ｒｅｄ The photoredox catalyst (B) has a voltage difference of 1.5 V vs. SCE or more.

[0022] The mechanism by which the dental adhesive composition of the present invention exhibits the effects of the present invention is not clear, but is presumed to be as follows: Ｓ１ ｒｅｄ A compound represented by the formula (I) is excited by light irradiation and functions as a strong oxidizing agent. When a dental adhesive composition contains this compound, a redox reaction occurs at the interface between the tooth and the dental adhesive composition when the dental adhesive composition is cured by irradiation with light such as visible light, generating a large amount of radicals. This large amount of radicals significantly accelerates the polymerization curing reaction at the adhesive interface, presumably improving tooth adhesion. Furthermore, many cationic photoredox catalysts undergo nucleophilic attack and decompose when coexisting with basic substances, which can reduce storage stability. In the present invention, the coexistence of the photoredox catalyst with an acidic group-containing polymerizable monomer allows high storage stability even for cationic photoredox catalysts. Furthermore, it is known that general oxidizing agents are prone to decomposition under acidic conditions. However, when the singlet excitation reduction potential E exceeds a certain value, Ｓ１ ｒｅｄ Since a "photoredox catalyst" having the formula (I) functions as an oxidizing agent only after being excited by light irradiation, it is possible to incorporate an oxidizing agent, which is normally unstable under acidic conditions, into a dental adhesive composition in the stable form of a "photoredox catalyst." In addition, it is also possible to have an oxidizing agent and a reducing agent, which would normally undergo a redox reaction when mixed together, coexist in the same material in a stable form. For example, high storage stability can be achieved even when a photoredox catalyst and a reducing agent are incorporated into the same material. The effects of the present invention are presumed to be achieved by the above-mentioned estimated mechanism. Each of the components contained in the dental adhesive composition of the present invention will be described below.

[0023] [Polymerizable Monomer (A) Having an Acidic Group] The dental adhesive composition of the present invention contains a polymerizable monomer (A) having an acidic group. The polymerizable monomer (A) having an acidic group is an essential component for the dental adhesive composition of the present invention to exhibit adhesive properties, and has the effect of demineralizing tooth tissue. The polymerizable monomer (A) having an acidic group is a polymerizable monomer having at least one acidic group such as a phosphate group, phosphonate group, pyrophosphate group, thiophosphate group, carboxylic acid group, or sulfonic acid group, and at least one polymerizable group such as an acryloyl group, methacryloyl group, acrylamide group, or methacrylamide group. From the viewpoint of adhesiveness to tooth tissue, the polymerizable monomer (A) having an acidic group is preferably monofunctional, having any one of an acryloyl group, methacryloyl group, acrylamide group, or methacrylamide group as the polymerizable group. Specific examples include the following.

[0024] Examples of the polymerizable monomer having a phosphoric acid group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, and 11-(meth)acryloyloxyundecyl dihydrogen phosphate. monofunctional (meth)acrylate compounds having a phosphoric acid group such as 2-(meth)acryloyloxyethylphenylhydrogenphosphate, 12-(meth)acryloyloxydodecyldihydrogenphosphate, 16-(meth)acryloyloxyhexadecyldihydrogenphosphate, 20-(meth)acryloyloxyeicosyldihydrogenphosphate, 2-(meth)acryloyloxyethylphenylhydrogenphosphate, 2-(meth)acryloyloxyethyl-2-bromoethylhydrogenphosphate, 2-(meth)acryloyloxyethyl-(4-methoxyphenyl)hydrogenphosphate, and 2-(meth)acryloyloxypropyl-(4-methoxyphenyl)hydrogenphosphate, as well as acid chlorides, alkali metal salts, ammonium salts, and amine salts thereof;Examples of suitable difunctional (meth)acrylate compounds having a phosphate group include bis[2-(meth)acryloyloxyethyl]hydrogenphosphate, bis[4-(meth)acryloyloxybutyl]hydrogenphosphate, bis[6-(meth)acryloyloxyhexyl]hydrogenphosphate, bis[8-(meth)acryloyloxyoctyl]hydrogenphosphate, bis[9-(meth)acryloyloxynonyl]hydrogenphosphate, bis[10-(meth)acryloyloxydecyl]hydrogenphosphate, and 1,3-di(meth)acryloyloxypropyl dihydrogenphosphate, as well as their acid chlorides, alkali metal salts, ammonium salts, and amine salts. Among these, 10-(meth)acryloyloxydecyl dihydrogenphosphate and 1,3-di(meth)acryloyloxypropyl dihydrogenphosphate are preferred.

[0025] 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, ammonium salts, and amine salts thereof.

[0026] Examples of the polymerizable monomer having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl] pyrophosphate, bis[4-(meth)acryloyloxybutyl] pyrophosphate, bis[6-(meth)acryloyloxyhexyl] pyrophosphate, bis[8-(meth)acryloyloxyoctyl] pyrophosphate, bis[10-(meth)acryloyloxydecyl] pyrophosphate, and acid chlorides, alkali metal salts, ammonium salts, and amine salts thereof.

[0027] Examples of the polymerizable monomer having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyeicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0028] Examples of the polymerizable monomer 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 Examples of suitable carboxylic acids include acryloylphthalic acid and its 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, and their acid chlorides, alkali metal salts, ammonium salts, and amine salts.

[0029] 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.

[0030] Among the polymerizable monomers (A) having an acidic group, polymerizable monomers having a phosphate group, polymerizable monomers having a pyrophosphate group, and polymerizable monomers having a carboxylic acid group are preferred because they exhibit superior adhesiveness to tooth structure, and polymerizable monomers having a phosphate group and polymerizable monomers having a carboxylic acid group are particularly preferred. Among them, (meth)acrylate-based monofunctional polymerizable monomers having a C6-20 alkyl group or a C6-20 alkylene group as the main chain in the molecule and a phosphate group, or (meth)acrylate-based monofunctional polymerizable monomers having a C6-20 alkyl group or a C6-20 alkylene group as the main chain in the molecule and a carboxylic acid group are more preferred, and (meth)acrylate-based monofunctional polymerizable monomers having a phosphate group and an C8-12 alkylene group as the main chain in the molecule are even more preferred. Also preferred are 10-methacryloyloxydecyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitic acid and 4-(meth)acryloyloxyethyl trimellitic anhydride, with 10-methacryloyloxydecyl dihydrogen phosphate being most preferred.

[0031] The polymerizable monomer (A) having an acidic group may be blended alone or in combination of two or more. The content of the polymerizable monomer (A) having an acidic group is not particularly limited as long as the effects of the present invention are achieved. However, from the viewpoint of superior adhesiveness, the content is preferably in the range of 1 to 50 parts by mass, more preferably 2 to 30 parts by mass, and even more preferably 3 to 25 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention. In this specification, "100 parts by mass of the total amount of polymerizable monomers" means, in the case of a bonding material or a pretreatment material, when the total amount of polymerizable monomers excluding the solvent is 100 parts by mass; in the case of a dental cement, when the total amount of polymerizable monomers contained in the first agent and the second agent is 100 parts by mass; and in the case of a dental self-adhesive composite resin, when the total amount of polymerizable monomers is 100 parts by mass.

[0032] [Photoredox catalyst (B)] The dental adhesive composition of the present invention has a singlet excited reduction potential E Ｓ１ ｒｅｄ The dental adhesive composition of the present invention contains a photoredox catalyst (B) having a singlet excited reduction potential E of 1.5 V vs. SCE or more. Since the dental adhesive composition of the present invention uses the photoredox catalyst (B) as the redox catalyst, the dental adhesive composition has excellent storage stability in the absence of light irradiation, and the singlet excited reduction potential E of the photoredox catalyst (B) is Ｓ１ ｒｅｄ Since the singlet excited reduction potential E is 1.5 V vs. SCE or more, the adhesiveness to tooth tissue is excellent when photocured, and the high adhesiveness to tooth tissue is maintained even after storage. Ｓ１ ｒｅｄ is preferably 1.6 V vs. SCE or more, more preferably 1.7 V vs. SCE or more, even more preferably 1.8 V vs. SCE or more, even more preferably 1.9 V vs. SCE or more, even more preferably 2.0 V vs. SCE or more, even more preferably 2.2 V vs. SCE or more, and even more preferably 2.5 V vs. SCE or more. Ｓ１ ｒｅｄ Although there is no particular limitation on the upper limit of the singlet excited reduction potential E, from the viewpoint of availability, etc., it is preferably 3.0 V vs. SCE or less.Ｓ１ ｒｅｄ is preferably 1.6 to 3.0 V vs. SCE, more preferably 1.7 to 3.0 V vs. SCE, even more preferably 1.8 to 3.0 V vs. SCE, even more preferably 1.9 to 3.0 V vs. SCE, even more preferably 2.0 to 3.0 V vs. SCE, even more preferably 2.2 to 3.0 V vs. SCE, and more preferably 2.5 to 3.0 V vs. SCE.

[0033] Singlet excited oxidation potential E of the photoredox catalyst (B) Ｓ１ оｘ is preferably negative. This allows the compound to be excited by light irradiation and function as a strong reducing agent, which is thought to significantly accelerate the polymerization and curing reaction at the adhesive interface and improve adhesion to tooth substrate. Ｓ１ оｘ is preferably −0.1 V vs. SCE or less, more preferably −0.5 V vs. SCE or less, even more preferably −0.8 V vs. SCE or less, even more preferably −0.9 V vs. SCE or less, and still more preferably −1.0 V vs. SCE or less. Ｓ１ оｘ Although there is no particular limitation on the lower limit of the singlet excited oxidation potential E, from the viewpoint of availability, it is preferably −3.0 V vs. SCE or more. Ｓ１ оｘ is preferably −3.0 to −0.1 V vs. SCE, more preferably −3.0 to −0.5 V vs. SCE, even more preferably −3.0 to −0.8 V vs. SCE, still more preferably −3.0 to −0.9 V vs. SCE, and more preferably −3.0 to −1.0 V vs. SCE.

[0034] The photoredox catalyst (B) is preferably a visible light redox catalyst (B). Here, the term "visible light redox catalyst (B)" refers to a photoredox catalyst (B) having an absorption spectrum that includes part or all of the wavelength range from 400 nm to 800 nm. This allows the dental adhesive composition according to the present invention to be photocured by irradiation with visible light. The photoredox catalyst (B) preferably has an absorption spectrum that includes a range of 400 nm to 500 nm. This is because the absorption spectrum of the photoredox catalyst (B) includes the wavelength of a blue LED, which is the light source used in dental irradiators, thereby enabling the photoredox catalyst (B) to be excited with high efficiency and achieve high reactivity. Here, "an absorption spectrum that includes a range of 400 nm to 500 nm" means that the molar extinction coefficient at any wavelength between 400 and 500 nm is 10 or greater. The molar absorption coefficient at any wavelength in the range of 400 to 500 nm is preferably 50 or more, more preferably 80 or more, even more preferably 100 or more, still more preferably 1,000 or more, still more preferably 4,000 or more, and still more preferably 6,000 or more. In addition, taking into consideration availability and the effect on the color of the composition, it is preferably 1,000,000 or less.

[0035] The photoredox catalyst (B) is not particularly limited, but at least one selected from the group consisting of compounds represented by the following formulas (1), (2), and (3) is preferably used.

[0036]

[0037] In formula (1), R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ and R ９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom; － is BF ４ － , P.F. ６ － , ClO４ － or HSO ４ － R in formula (1) １ , R ２ and R ３ are each independently more preferably an alkyl group having 1 to 4 carbon atoms, and even more preferably a methyl group, an isopropyl group, or a t-butyl group.

[0038] The compound represented by the formula (1) is more preferably a compound represented by the formula (1A). １ , R ２ , R ３ , R ５ and R ９ are the same as the same symbols in formula (1).

[0039]

[0040]

[0041] In formula (2), R １１ , R １３ , R １４ , R １５ , R １６ , and R １８ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R １２ , R １７ , and R １９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms; － is BF ４ － , P.F. ６ － , ClO ４ － or HSO ４ － Preferably, R １１ , R １３ , R １４ , R １５ , R １６ , and R １８ is a hydrogen atom, and R １２ and R １７ is a hydrogen atom, and R １９is an alkyl group having 1 to 4 carbon atoms.

[0042]

[0043] In formula (3), R ２１ , R ２２ , R ２３ and R ２４ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a carboxylic acid group or an ester thereof having 1 to 10 carbon atoms, a hydroxyl group, a cyano group, or a halogen atom. ２１ ~R ２４ Among them, R ２１ , R ２２ , R ２３ is a hydrogen atom, and R ２４ is preferably a cyano group or a carboxylic acid ester group.

[0044] Specific examples of the compound represented by formula (1) include 2,4,6-triphenylpyrylium tetrafluoroborate, 2,4,6-triphenylpyrylium hydrogen sulfate, 2,4,6-tri-p-tolyl-pyrylium tetrafluoroborate, 2,4,6-tris(4-methoxyphenyl)pyrylium tetrafluoroborate, 2,4,6-tris(4-fluorophenyl)pyrylium tetrafluoroborate, 4-mesityl-2,6-diphenylpyrylium tetrafluoroborate, 4-mesityl-2,6-di-p-tolylpyrylium tetrafluoroborate, 4-(4-butoxyphenyl)-2, Examples of suitable pyrylium tetrafluoroborate include 6-bis(4-methoxyphenyl)pyrylium tetrafluoroborate, 4-(4-butoxyphenyl)-2,6-diphenylpyrylium tetrafluoroborate, 2,6-bis(4-methoxyphenyl)-4-phenylpyrylium tetrafluoroborate, 4-(4-butoxyphenyl)-2,6-diphenylpyrylium tetrafluoroantimonate, 2,4,6-tri(4-methoxyphenyl)pyrylium perchlorate, 4-(3,4-diethoxyphenyl)-2,6-bis(4-methoxyphenyl)pyrylium tetrafluoroborate, 4-(4-dimethylaminophenyl)-2,6-diphenylpyrylium perchlorate, 2-(4-nitrophenyl)-4,6-bis(4-butylphenyl)pyrylium tetrafluoroborate, and 2-(3,4-dichlorophenyl)-4-(4-methoxyphenyl)-6-phenylpyrylium tetrafluoroborate. Of these, 2,4,6-triphenylpyrylium tetrafluoroborate, 2,4,6-tri-p-tolyl-pyrylium tetrafluoroborate, 2,4,6-tris(4-methoxyphenyl)pyrylium tetrafluoroborate, 2,4,6-tris(4-fluorophenyl)pyrylium tetrafluoroborate, 4-mesityl-2,6-diphenylpyrylium tetrafluoroborate, and 4-mesityl-2,6-di-p-tolylpyrylium tetrafluoroborate are preferred.

[0045] Examples of the compound represented by formula (2) include 9-mesityl-10-methylacridinium perchlorate, 9-mesityl-10-methylacridinium tetrafluoroborate, 9-mesityl-10-phenylacridinium perchlorate, 9-mesityl-10-phenylacridinium tetrafluoroborate, 9-mesityl-3,6-di-t-butyl-10-phenylacridinium tetrafluoroborate, 9-mesityl-1,3,6,8-tetramethoxy-10-phenylacridinium tetrafluoroborate, and 2,7,10-trimethyl-9-mesitylacridinium perchlorate. Of these, 9-mesityl-10-methylacridinium perchlorate and 9-mesityl-10-methylacridinium tetrafluoroborate are preferred.

[0046] Examples of the compound represented by formula (3) include 9,10-dicyanoanthracene, 9-cyanoanthracene, 9-cyanoanthracene-10-carboxylic acid methyl ester, 2,4,9,10-tetracyanoanthracene, and 2,6,9,10-tetracyanoanthracene.

[0047] The photoredox catalyst (B) may be blended alone or in combination of two or more. The content of the photoredox catalyst (B) is not particularly limited as long as the effects of the present invention are achieved. However, from the viewpoint of superior adhesion, the content is preferably 0.001 parts by mass or more relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention. From the viewpoint of suppressing coloration and suppressing light shielding so that light is sufficiently irradiated onto the photocatalyst (B), the content is preferably 3 parts by mass or less. From these viewpoints, the content of the photoredox catalyst (B) is preferably in the range of 0.001 to 5 parts by mass, more preferably 0.005 to 3 parts by mass, even more preferably 0.01 to 2 parts by mass, even more preferably 0.01 to 1.5 parts by mass, even more preferably 0.01 to 1 part by mass, and even more preferably 0.01 to 0.8 parts by mass relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0048] [Polymerizable Monomer (C) Not Having an Acidic Group] The dental adhesive composition of the present invention may or may not contain a polymerizable monomer (C) not having an acidic group, but it is preferable that it contains one. The polymerizable monomer (C) not having 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 (C) not having an acidic group may be used alone or in combination of two or more types. Suitable examples of the polymerizable monomer (C) not having an acidic group include the following hydrophilic polymerizable monomer (C-1) and hydrophobic polymerizable monomer (C-2).

[0049] The hydrophilic polymerizable monomer (C-1) refers to a polymerizable monomer having a solubility in water of 10% by mass or more at 25° C. Preferably, the solubility is 30% by mass or more, and more preferably, the polymerizable monomer is soluble in water at any ratio at 25° C. The hydrophilic polymerizable monomer (C-1) promotes the penetration of the components of the dental adhesive 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 (C-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)ethyltrimethylammonium 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."

[0050] The hydrophobic polymerizable monomer (C-2) refers to a polymerizable monomer having a solubility in water of less than 10% by mass at 25° C. Examples of the hydrophobic polymerizable monomer (C-2) include aromatic compound-based monofunctional polymerizable monomers, bifunctional polymerizable monomers, aliphatic compound-based monofunctional polymerizable monomers, bifunctional polymerizable monomers, and trifunctional or higher functional polymerizable monomers. The hydrophobic polymerizable monomer (C-2) improves the mechanical strength, handleability, etc. of the dental adhesive composition.

[0051] Examples of aromatic compound-based monofunctional polymerizable monomers include benzyl (meth)acrylate, p-cumyl-phenoxyethylene glycol (meth)acrylate, 2-phenoxybenzyl (meth)acrylate, etc. Among these, benzyl methacrylate, 2-phenoxybenzyl (meth)acrylate, and p-cumyl-phenoxyethylene glycol methacrylate are preferred.

[0052] Examples of aromatic compound-based bifunctional polymerizable monomers include aromatic di(meth)acrylates. Specific examples of aromatic compound-based 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)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytri ...triethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2 1,4-bis(2-(meth)acryloyloxyethyl)pyromellitate, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxyethoxyphenyl)propane, 2-(4-(meth)acryloyloxydiethoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2-(4-(meth)acryloyloxydipropoxyphenyl)-2-(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypropoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxyisopropoxyphenyl)propane, and 1,4-bis(2-(meth)acryloyloxyethyl)pyromellitate. 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.

[0053] Examples of the aliphatic compound-based monofunctional polymerizable monomer include methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobornyl (meth)acrylate, stearyl (meth)acrylate, dicyclopentanyl (meth)acrylate, butoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, tetrahydrofurfuryl methacrylate, etc. Among these, isobornyl methacrylate and tetrahydrofurfuryl methacrylate (hereinafter sometimes abbreviated as "THF-MA") are preferred.

[0054] Examples of the aliphatic compound-based bifunctional polymerizable monomer include erythritol di(meth)acrylate, sorbitol di(meth)acrylate, mannitol di(meth)acrylate, pentaerythritol di(meth)acrylate, dipentaerythritol di(meth)acrylate, glycerol di(meth)acrylate (hereinafter sometimes abbreviated as "GDMA"), 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, bifunctional (meth)acrylic acid ester polymerizable monomers such as N-methacryloyloxyethyl acrylamide, N-methacryloyloxypropyl acrylamide, N-methacryloyloxybutyl acrylamide, N-(1-ethyl-(2-methacryloyloxy)ethyl)acrylamide, and N-(2-(2-methacryloyloxyethoxy)ethyl)acrylamide. Of these, glycerol dimethacrylate, triethylene glycol di(meth)acrylate, neopentyl glycol dimethacrylate, 2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)dimethacrylate, and 1,2-bis(3-methacryloyloxy-2-hydroxypropyloxy)ethane are preferred.

[0055] 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, and 1,7-diacryloyloxy-2,2,6,6-tetraacryloyloxymethyl-4-oxaheptane.

[0056] Among the polymerizable monomers (C) not having an acidic group, HEMA, GDMA, Bis-GMA, D-2.6E, TEGDMA, and THF-MA are more preferred from the viewpoint of the adhesive strength and polymerization curability of the dental adhesive composition of the present invention.

[0057] The above-mentioned polymerizable monomer (C) not having an acidic group (hydrophilic polymerizable monomer (C-1) and hydrophobic polymerizable monomer (C-2)) may each be contained alone or in combination of two or more. The content of the polymerizable monomer (C) not having an acidic group is not particularly limited as long as the effects of the present invention are exhibited. However, from the viewpoints of high penetration into tooth structure and excellent adhesion of the composition, and of the cured product having sufficient mechanical strength, the content is preferably in the range of 20 to 99 parts by mass, more preferably 30 to 98 parts by mass, even more preferably 40 to 95 parts by mass, even more preferably 60 to 95 parts by mass, even more preferably 70 to 95 parts by mass, and even more preferably 80 to 95 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention. The content of the hydrophilic polymerizable monomer (C-1) in the total amount of the hydrophilic polymerizable monomer (C-1) and the hydrophobic polymerizable monomer (C-2) is more preferably in the range of 1.0 to 95 mass%, more preferably in the range of 5.0 to 70 mass%, and even more preferably in the range of 0.5 to 60 mass%.

[0058] Next, the polymerization initiator system will be described. The dental adhesive composition of the present invention may further contain an organic peroxide (D) and a reducing agent (E) as a polymerization initiator system. By combining such polymerization initiator systems and using them together with other components, it is possible to set the curing rate within an appropriate range, and the adhesiveness to tooth substrate and storage stability are excellent, and high adhesiveness to tooth substrate is maintained even after storage.

[0059] [Organic Peroxide (D)] The dental adhesive composition of the present invention may or may not contain an organic peroxide (D). Since the dental adhesive composition of the present invention contains a polymerizable monomer (A) having an acidic group and a photoredox catalyst (B), the photoredox catalyst (B) itself can function as an oxidizing agent when excited, even without containing the organic peroxide (D), resulting in improved adhesion to tooth tissue and high storage stability. Examples of the organic peroxide (D) include diacyl peroxides, peroxy esters, dialkyl peroxides, peroxy ketals, ketone peroxides, and hydroperoxides. Specific examples of diacyl peroxides include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, and m-toluoyl peroxide. Specific examples of peroxyesters include t-butylperoxybenzoate, bis(t-butylperoxy)isophthalate, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane, t-butylperoxy-2-ethylhexanoate, and t-butylperoxyisopropyl carbonate. Specific examples of dialkyl peroxides include dicumyl peroxide, di-t-butyl peroxide, and lauroyl peroxide. Specific examples of peroxyketals include 1,1-bis(t-butylperoxy)3,3,5-trimethylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, and 1,1-bis(t-hexylperoxy)cyclohexane. Specific examples of ketone peroxides include methyl ethyl ketone peroxide, cyclohexanone peroxide, and methyl acetoacetate peroxide. Specific examples of hydroperoxides include t-butyl hydroperoxide, cumene hydroperoxide, p-diisopropylbenzene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide.

[0060] Among the organic peroxides (D), hydroperoxides and peroxyesters are particularly preferred. Among the hydroperoxides, t-butyl hydroperoxide, cumene hydroperoxide, and 1,1,3,3-tetramethylbutyl hydroperoxide are preferred. Furthermore, among the peroxyesters, t-butyl peroxybenzoate is preferred.

[0061] The organic peroxide (D) may be blended alone or in combination of two or more. When the dental adhesive composition of the present invention contains an organic peroxide (D), the content of the organic peroxide (D) is preferably in the range of 0.01 to 10 parts by mass, more preferably in the range of 0.1 to 5 parts by mass, and even more preferably in the range of 0.5 to 3 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention, from the viewpoints of curability, mechanical strength of the cured product, adhesion to tooth substrate, and storage stability.

[0062] [Reducing Agent (E)] The dental adhesive composition of the present invention may or may not contain a reducing agent (E). Since the dental adhesive composition of the present invention contains a polymerizable monomer (A) having an acidic group and a photoredox catalyst (B), when the photoredox catalyst (B) is excited, it can itself function as a reducing agent, thereby improving adhesion to tooth tissue and providing high storage stability. Examples of the reducing agent (E) include thiourea compounds, sulfinic acids and their salts, sulfites, hydrogen sulfites, borate compounds, barbituric acid and its derivatives, and ascorbic acid derivatives.

[0063] Examples of the thiourea compound include thiourea, methylthiourea, ethylthiourea, ethylenethiourea, N,N'-dimethylthiourea, N,N'-diethylthiourea, N,N'-di-n-propylthiourea, N,N'-dicyclohexylthiourea, trimethylthiourea, triethylthiourea, tri-n-propylthiourea, tricyclohexylthiourea, tetramethylthiourea, tetraethylthiourea, tetra-n-propylthiourea, tetracyclohexylthiourea, 1-(2-pyridyl)-2-thiourea, 4,4-dimethylethylenethiourea, etc. One type of the thiourea compound may be used alone, or two or more types may be used in combination.

[0064] Examples of the sulfinic acid and its salts 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 sulfinic acids and their salts include calcium benzenesulfinate, 2,4,6-triethylbenzenesulfinic acid, sodium 2,4,6-triethylbenzenesulfinate, potassium 2,4,6-triethylbenzenesulfinate, lithium 2,4,6-triethylbenzenesulfinate, calcium 2,4,6-triethylbenzenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, sodium 2,4,6-triisopropylbenzenesulfinate, potassium 2,4,6-triisopropylbenzenesulfinate, lithium 2,4,6-triisopropylbenzenesulfinate, and calcium 2,4,6-triisopropylbenzenesulfinate. Among these, sodium benzenesulfinate, sodium p-toluenesulfinate, 2,4,6-triisopropylbenzenesulfinic acid, and sodium 2,4,6-triisopropylbenzenesulfinate are preferred. The sulfinic acids and their salts may be used alone or in combination of two or more.

[0065] Examples of sulfites include sodium sulfite, potassium sulfite, calcium sulfite, and ammonium sulfite. Examples of hydrogen sulfites include sodium hydrogen sulfite and potassium hydrogen sulfite. Examples of borate compounds include arylborate compounds having 1 to 4 aryl groups per molecule (e.g., tetraphenylboron, tetrakis(p-chlorophenyl)boron, etc.) and salts thereof. Examples of barbituric acid and its derivatives include barbituric acid, 5-butylbarbituric acid, 1,3,5-trimethylbarbituric acid, 1-cyclohexyl-5-ethylbarbituric acid, 1-benzyl-5-phenylbarbituric acid, and salts thereof.

[0066] Examples of ascorbic acid derivatives include salts, esters, ethers, etc. of ascorbic acid. Among these, salts and esters of ascorbic acid are preferred.

[0067] Examples of salts of ascorbic acid include sodium L-ascorbate, calcium L-ascorbate, potassium ascorbate, and stereoisomers thereof (e.g., sodium isoascorbate, etc.), etc. Among these, sodium L-ascorbate is preferred.

[0068] Esters of ascorbic acid include those formed by reacting one or more hydroxy groups of ascorbic acid with a carboxylic acid. Suitable examples of the carboxylic acid include fatty acids such as saturated or unsaturated fatty acids having 6 to 30 carbon atoms, such as caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, elaidic acid, vaccenic acid, linoleic acid, linoleelaidic acid, α-linolenic acid, arachidonic acid, eicosapentaenoic acid, erucic acid, and docosahexaenoic acid. The number of carbon atoms in the fatty acid is preferably 10 to 28, more preferably 12 to 26, and even more preferably 14 to 24. Among these, esters of stearic acid and ascorbic acid, and esters of palmitic acid and ascorbic acid (ascorbyl palmitate) are particularly preferred.

[0069] Examples of the ethers of ascorbic acid include ethyl ascorbate and cetyl ascorbate.

[0070] The ascorbic acid compound may be blended singly or in combination of two or more kinds.

[0071] When the dental adhesive composition of the present invention contains a reducing agent (E), the content of the reducing agent (E) is not particularly limited as long as the effects of the present invention are achieved, but in terms of achieving high penetration of the composition into tooth structure and excellent adhesiveness, and also providing a cured product with sufficient mechanical strength, the content of the reducing agent (E) is preferably in the range of 0.01 to 5.0 parts by mass, more preferably in the range of 0.02 to 3.0 parts by mass, and even more preferably in the range of 0.03 to 2.0 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0072] From the viewpoint of preventing the reaction between the organic peroxide (D) and the reducing agent (E) during storage, the dental adhesive composition may be in an embodiment containing the organic peroxide (D) but not the reducing agent (E), or may be in an embodiment not containing the organic peroxide (D) but containing the reducing agent (E). Specifically, when the dental adhesive composition is a one-component type (one-liquid type, one-paste type, etc.), the one-component dental adhesive composition may be in an embodiment containing the organic peroxide (D) but not the reducing agent (E), or may be in an embodiment not containing the organic peroxide (D) but containing the reducing agent (E). Furthermore, when the dental adhesive composition is a two-component type (two-component type, two-paste type, etc.), each component may independently be in an embodiment containing the organic peroxide (D) but not the reducing agent (E), or may be in an embodiment not containing the organic peroxide (D) but containing the reducing agent (E). For example, when the dental adhesive composition is a two-component type, one component may contain an organic peroxide (D) but not a reducing agent (E), and the other component may contain no organic peroxide (D) but not a reducing agent (E). Also, when the dental adhesive composition is a two-component type, one component may contain an organic peroxide (D) but not a reducing agent (E), and the other component may contain no organic peroxide (D) or no reducing agent (E). Also, when the dental adhesive composition is a two-component type, one component may contain no organic peroxide (D) but not a reducing agent (E), and the other component may contain no organic peroxide (D) or no reducing agent (E).

[0073] [Phosphine Compound (F)] The dental adhesive composition of the present invention may or may not further contain a phosphine compound (F) having an electron-withdrawing group. The phosphine compound (F) having an electron-withdrawing group is presumed to play a role in preventing polymerization inhibition by oxygen and promoting polymerization, and to function as a part of a chemical polymerization initiator system.

[0074] Specific examples of the compound (F) include compounds represented by the following formula (4): The compound (F) may be used alone or in combination of two or more.

[0075]

[0076] In formula (4), R ３１ ~R ４５ each independently represents a hydrogen atom, a halogen atom, a polar group, an alkyl group which may or may not have a substituent, or an alkoxy group which may or may not have a substituent; R ３１ , R ３３ , R ３５ , R ３６ , R ３８ , R ４０ , R ４１ , R ４３ and R ４５ at least one of is at least one electron-withdrawing group selected from the group consisting of a halogen atom, a haloalkyl group, a substituted or unsubstituted acyl group, a substituted or unsubstituted ester group, a substituted or unsubstituted amide group, a substituted or unsubstituted sulfonyl group, and a cyano group.

[0077] R ３１ ~R ４５ The alkyl group, which may or may not have a substituent, may be either linear or branched. ３１ ~R ４５ The number of carbon atoms in the alkyl group of R 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. ３１ ~R ４５ Examples of the alkyl group of R include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a 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. ３１ ~R ４５ The alkyl group in R may be unsubstituted. ３１ ~R ４５ Examples of the substituent on the alkyl group include a halogen atom, a hydroxy group, an alkoxy group having 1 to 6 carbon atoms, a dialkylamino group having an alkyl group having 1 to 6 carbon atoms, and an amino group.

[0078] R３１ ~R ４５ Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

[0079] R ３１ ~R ４５ Examples of the polar group 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 carboxylic acid salt group, a sulfonic acid group, a sulfonic acid ester group, a sulfonic acid chloride group, a sulfonic acid amide group, a sulfonic acid salt 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 viewpoint of curability and the mechanical strength of the cured product, the carboxylic acid group, the carboxylic acid ester group, the carboxylic acid chloride group, the carboxylic acid amide group, Carboxylate groups, sulfonic acid groups, sulfonate ester groups, sulfonic acid chloride groups, sulfonate amide groups, sulfonate groups, and aldehyde groups are preferred, with carboxylic acid groups, carboxylic acid ester groups, carboxylic acid chloride groups, carboxylic acid groups, sulfonate groups, sulfonate ester groups, sulfonate acid chloride groups, sulfonate groups, and aldehyde groups being more preferred, and carboxylic acid groups, carboxylic acid ester groups, carboxylic acid chloride groups, carboxylic acid groups, sulfonate groups, sulfonate ester groups, sulfonate acid chloride groups, and sulfonate groups being even more preferred. Salts of carboxylic acid 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. R ３１ ~R ４５ In the case where R is a polar group, the number of polar groups is preferably 1 to 9, more preferably 1 to 5, and even more preferably 1 to 3. ３１ ~R ４５ When is an alkyl group having a substituent, specific examples thereof include a trifluoromethyl group.

[0080] R ３１ ~R ４５ The alkoxy group, which may or may not have a substituent, may be either linear or branched. ３１ ~R ４５The number of carbon atoms in the alkoxy group 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. ３１ ~R ４５ Examples of the alkoxy group of R 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, and a neohexyloxy group. ３１ ~R ４５ The substituent of the alkoxy group in R ３１ ~R ４５ The substituents for the alkyl group are the same as those for the alkyl group.

[0081] R ３１ ~R ４５ may be the same or different. ３１ ~R ４５ may be, for example, partly the same hydrogen atom, alkyl group or alkoxy group.

[0082] Examples of the compound represented by formula (4) above include phosphine compounds such as (2-fluorophenyl)diphenylphosphine, (2-chlorophenyl)diphenylphosphine, (2-bromophenyl)diphenylphosphine, (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.

[0083] When the dental adhesive composition of the present invention contains compound (F), the content of compound (F) is preferably in the range of 0.005 to 10 parts by mass, more preferably in the range of 0.01 to 5 parts by mass, and even more preferably in the range of 0.05 to 3 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention, from the viewpoints of curability, mechanical strength of the cured product, and adhesiveness to tooth structure.

[0084] [Photopolymerization initiator (G)] The dental adhesive composition of the present invention may or may not contain a conventional photopolymerization initiator (G). However, from the viewpoint of strong adhesiveness and storage stability, it is preferable to contain a photopolymerization initiator (G). Examples of the photopolymerization initiator (G) include α-diketones, ketals, thioxanthones, (bis)acylphosphine oxides, and α-aminoacetophenones.

[0085] Examples of α-diketones include dl-camphorquinone (commonly known as "CQ"), benzil, and 2,3-pentanedione.

[0086] Examples of ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0087] Examples of thioxanthones include 2-chlorothioxanthone and 2,4-diethylthioxanthone.

[0088] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, benzoylbis(2,6-dimethylphenyl)phosphine oxide, water-soluble acylphosphine oxide compounds disclosed in JP-B-3-57916, and salts thereof (for example, sodium salts, potassium salts, ammonium salts). 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 (for example, 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.

[0089] 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.

[0090] The photopolymerization initiator (G) may be used alone or in combination of two or more. When the dental adhesive composition of the present invention contains the photopolymerization initiator (G), the content of the photopolymerization initiator (G) is not particularly limited, but from the viewpoint of the curability of the resulting dental adhesive composition, the content is preferably 0.001 to 10 parts by mass, more preferably 0.005 to 5 parts by mass, and even more preferably 0.01 to 3 parts by mass, relative to 100 parts by mass of the total amount of the polymerizable monomers in the dental adhesive composition of the present invention.

[0091] [Polymerization accelerator] In order to enhance photocurability, the photopolymerization initiator may be used in combination with a polymerization accelerator for the photopolymerization initiator, but it is not necessary to use them in combination, but it is preferable to use them in combination. Examples of the polymerization accelerator for the photopolymerization initiator include tertiary amines, aldehydes, thiol compounds, and triazine compounds substituted with a trihalomethyl group.

[0092] 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-di(2-hydroxyethyl)-p-toluidine, N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis(2-hydroxyethyl)-4-ethylaniline, N,N-bis(2-hydroxyethyl)-4-isopropylaniline, N,N-bis(2-hydroxyethyl)-4-t-butylaniline, N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline, Examples of the methyl alcohol include N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, 2-(methacryloyloxy)ethyl 4-(N,N-dimethylamino)benzoate, ethyl 4-(N,N-dimethylamino)benzoate, butyl 4-(N,N-dimethylamino)benzoate, N-methyldiethanolamine, 4-(N,N-dimethylamino)benzophenone, trimethylamine, triethylamine, N-methyldiethanolamine, N-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, such as dimethylaminobenzaldehyde, p-methoxybenzaldehyde, p-ethoxybenzaldehyde, and p-n-octyloxybenzaldehyde.Examples of the thiol compound include 3-mercaptopropyltrimethoxysilane, 2-mercaptobenzoxazole, decanethiol, thiobenzoic acid, etc. As the triazine-based compound substituted with a trihalomethyl group, any known s-triazine compound having at least one trihalomethyl group such as a trichloromethyl group or a tribromomethyl group can be used without any limitation.

[0093] The polymerization accelerator for the photopolymerization initiator may be used alone or in combination of two or more kinds. When the dental adhesive composition of the present invention contains a polymerization accelerator for the photopolymerization initiator, the content of the polymerization accelerator for the photopolymerization initiator is not particularly limited, but from the viewpoint of the curability of the obtained dental adhesive composition, it is preferably 0.001 to 10 parts by mass, more preferably 0.005 to 5 parts by mass, and even more preferably 0.01 to 3 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0094] [Filler (H)] The dental adhesive composition of the present invention may or may not contain a filler (H) in order to obtain sufficient workability of the composition and sufficient mechanical strength of the cured product.

[0095] As the filler (H), any filler can be used as long as it does not impair the effects of the present invention, and examples thereof include inorganic fillers, organic fillers, and composite fillers of inorganic fillers and organic fillers. The filler (H) may be blended singly or in combination of two or more types. The average particle size of the filler (H) is preferably 0.001 to 10 μm, and more preferably 0.001 to 5 μm.

[0096] Inorganic fillers include silica; silica-based minerals such as kaolin, clay, mica, and mica; silica-based Al fillers; ２ O ３ , B ２ O ３ , TiO ２ , ZrO ２ , BaO, La ２ O ３ , SrO, ZnO, CaO, P２ O ５ , Li ２ O, Na ２ Examples of suitable inorganic fillers include ceramics and glasses containing 0 and the like. Examples of suitable glass include lithium borosilicate glass, borosilicate glass, bioglass, lanthanum glass, barium glass, strontium glass, soda glass, zinc glass, and fluoroaluminosilicate glass. Suitable inorganic fillers 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, finely divided silica particles having an average particle size of 0.001 to 0.1 μm are 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.

[0097] Examples of organic fillers include polymethyl methacrylate, polyethyl methacrylate, polyfunctional methacrylate polymers, polyamide, polystyrene, polyvinyl chloride, chloroprene rubber, nitrile rubber, and styrene-butadiene rubber.

[0098] Examples of composite fillers of inorganic and organic fillers include those in which inorganic fillers are dispersed in organic fillers, and inorganic / organic composite fillers in which inorganic fillers are coated with various polymers.

[0099] In order to improve curability, mechanical strength, and handleability, the filler (H) may be surface-treated in advance with a known surface treatment agent such as a silane coupling agent. Examples of the surface treatment agent include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane.

[0100] The average particle size (average primary particle size) can be determined by laser diffraction scattering or electron microscope observation of the particles. Specifically, laser diffraction scattering is convenient for measuring the particle size of particles 0.1 μm or larger, while electron microscope observation is convenient for measuring the particle size of ultrafine particles less than 0.1 μm. 0.1 μm is the value measured by laser diffraction scattering. For laser diffraction scattering, for example, measurements can be made on a volume basis using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation) using a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium. For electron microscope observation, a scanning electron microscope (SU3800, S-4000, etc., manufactured by Hitachi High-Technologies Corporation) can be used. For electron microscope observation, an electron microscope photograph of the particles is taken, and the particle sizes of particles (200 or more) observed within a unit field of view of the photograph are measured using image analysis particle size distribution measurement software (Mac-View (manufactured by Mountec Co., Ltd.)). In this case, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average primary particle diameter is calculated from the number of particles and their particle diameters.

[0101] When the dental adhesive composition of the present invention contains a filler (H), the content of the filler (H) is not particularly limited as long as the effects of the present invention are exhibited, but it is preferably in the range of 1 to 300 parts by mass, more preferably 3 to 250 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention. Within these ranges, sufficient mechanical strength and operability of the cured product can be obtained.

[0102] [Transition Metal Compound] The dental adhesive composition of the present invention may or may not contain a transition metal compound. Examples of the transition metal compound include, but are not limited to, copper compounds and vanadium compounds.

[0103] Examples of copper compounds include copper(II) carboxylates, β-diketone copper(II), β-ketoester copper(II), copper alkoxides, copper dithiocarbamates, and salts of copper with 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) octenoate, copper(II) naphthenate, copper(II) methacrylate, and copper(II) 4-cyclohexylbutyrate. Examples of copper(II) β-diketones include copper(II) acetylacetonate, copper(II) trifluoroacetylacetonate, copper(II) hexafluoroacetylacetonate, copper(II) 2,2,6,6-tetramethyl-3,5-heptanedionatocopper(II), 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 dithiocarbamates 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 combinations of two or more. Among these, from the viewpoints of solubility and reactivity with polymerizable monomers, copper(II) carboxylate, copper(II) β-diketone, and copper(II) β-ketoester are preferred, with copper(II) acetate and copper(II) acetylacetonate being more preferred.

[0104] The vanadium compound is preferably a tetravalent and / or pentavalent vanadium compound. Examples of the tetravalent and / or pentavalent vanadium compound include divanadium(IV) tetroxide, vanadyl acetylacetonate(IV), vanadium(IV) oxide stearate, oxovanadium(IV) oxalate, vanadyl(IV) sulfate, vanadium naphthenate, vanadium benzoylacetonate, bis(maltolate)oxovanadium(IV), oxobis(1-phenyl-1,3-butanedionato)vanadium(IV), vanadium(V) pentoxide, vanadium(V) oxytriisopropoxide, sodium metavanadate(V), and ammonium metavanadate(V). Among these, vanadium acetylacetonate, vanadyl acetylacetonate(IV), and bis(maltolato)oxovanadium(IV) are preferred from the viewpoint of adhesiveness, and vanadyl acetylacetonate(IV) and bis(maltolato)oxovanadium(IV) are more preferred. The vanadium compounds can be used singly or in combination of two or more.

[0105]

[0023] When the dental adhesive composition of the present invention contains the transition metal compound, the content of the transition metal compound 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 0.0008 to 0.2 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention, from the viewpoints of curability, mechanical strength, and adhesion to tooth structure.

[0106] [Fluoride Ion-Releasing Substance] The dental adhesive composition of the present invention may or may not further contain a fluoride ion-releasing substance. By incorporating a fluoride ion-releasing substance, a dental adhesive composition capable of imparting acid resistance to tooth structure can be obtained. Examples of such fluoride ion-releasing substances 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 substances may be used alone or in combination of two or more. When the dental adhesive composition of the present invention contains a fluoride ion-releasing substance, the content of the fluoride ion-releasing substance is preferably in the range of 0.01 to 30 parts by mass, more preferably in the range of 0.02 to 20 parts by mass, and even more preferably in the range of 0.05 to 15 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0107] [pH Adjuster] The dental adhesive composition of the present invention may or may not contain a pH adjuster. The pH adjuster is used for the purpose of adjusting and stabilizing the pH of the dental adhesive composition of the present invention. The pH adjuster is not particularly limited as long as it achieves the effects of the present invention, but tertiary aliphatic amines are preferably used. Examples of tertiary aliphatic amines that can be used in the present invention include N-methyldiethanolamine, N-ethyldiethanolamine, N-n-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl(meth)acrylate, N-methyldiethanolamine di(meth)acrylate, N-ethyldiethanolamine di(meth)acrylate, triethanolamine mono(meth)acrylate, triethanolamine di(meth)acrylate, triethanolamine tri(meth)acrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, N-methyldiethanolamine and triethanolamine are preferred. Triethanolamine and 2-(dimethylamino)ethyl methacrylate are preferably used. The pH adjusters may be used alone or in combination of two or more.

[0108] When the dental adhesive composition of the present invention contains a pH adjuster, the content of the pH adjuster is preferably in the range of 0.1 to 5.0 parts by mass, more preferably in the range of 0.5 to 3.0 parts by mass, and even more preferably in the range of 1.0 to 2.0 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0109] [Solvent] The dental adhesive composition of the present invention may or may not contain a solvent, provided that the effects of the present invention are not impaired. These may be blended singly or in combination of two or more. Examples of the solvent include aqueous solvents such as water and alcohol (e.g., ethanol), and organic solvents. When the dental adhesive composition of the present invention contains a solvent, the content of the solvent is preferably in the range of 10 to 80 parts by mass, more preferably in the range of 20 to 60 parts by mass, and even more preferably in the range of 30 to 50 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0110] [Other Additives] In addition, the dental adhesive composition of the present invention may or may not contain additives such as a polymerization inhibitor, an ultraviolet absorber, a thickener, a colorant, an antibacterial agent, and a fragrance, as long as the effects of the present invention are not impaired. These may be blended alone or in combination of two or more. Examples of polymerization inhibitors include hydroquinone, hydroquinone monomethyl ether, dibutylhydroquinone, dibutylhydroquinone monomethyl ether, t-butylcatechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, and 2,6-di-t-butyl-4-methylphenol.

[0111] When the dental adhesive composition of the present invention contains other additives, the content of the other additives is preferably in the range of 0.01 to 15.0 parts by mass, more preferably in the range of 0.01 to 10.0 parts by mass, even more preferably in the range of 0.01 to 3.0 parts by mass, still more preferably in the range of 0.05 to 2.0 parts by mass, and still more preferably in the range of 0.05 to 0.2 parts by mass, relative to 100 parts by mass of the total amount of polymerizable monomers in the dental adhesive composition of the present invention.

[0112] The content of the polymerizable monomer is preferably in the range of 80 to 99.9 parts by mass, more preferably in the range of 85 to 99.5 parts by mass, and even more preferably in the range of 89 to 99.0 parts by mass, relative to 100 parts by mass of the total amount of the components of the dental adhesive composition of the present invention excluding the solvent and filler.

[0113] [Method for Producing Dental Adhesive Composition] The dental adhesive composition of the present invention may be prepared according to conventional methods, depending on the types and amounts of the components. The dental adhesive composition of the present invention is used in a one-component or two-component form. The one-component form can be selected from liquid and paste forms, such as a one-component dental bonding material and a one-paste dental self-adhesive composite resin. The two-component form can be selected from powder and liquid forms, paste and liquid forms, and two-paste forms, as appropriate. However, from the viewpoint of ease of use, a more preferred embodiment is a two-paste form. In the case of a two-paste form, it is preferable to store the pastes separately from each other and then mix and harden the two pastes immediately before use by chemical polymerization. The paste is typically prepared by mixing a liquid component prepared by mixing components other than the filler (H) with the filler (H) (powder). An example of a two-paste form is a dental self-adhesive resin cement.

[0114] [Kit] The dental adhesive composition of the present invention can also be used as a kit. Examples of the kit include a kit of a one-component dental bonding material containing the photoredox catalyst (B) (dental adhesive composition of the present invention) and a two-paste dental composition, and a kit of a one-component dental bonding material containing the photoredox catalyst (B) (dental adhesive composition of the present invention) and a one-paste dental composition.

[0115] [Uses of Dental Adhesive Composition and Kit] The dental adhesive composition and kit of the present invention can be suitably used as a one-component dental bonding material, a dental self-adhesive composite resin, or a dental self-adhesive resin cement. The dental adhesive composition and kit of the present invention are used to bond dental prostheses such as crown restoration filling materials, crowns, inlays, and bridges to tooth structure in damaged areas of affected teeth.

[0116] The present invention includes embodiments in which the above-described configurations are combined in various ways within the scope of the technical concept of the present invention, as long as the effects of the present invention are achieved.

[0117] 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 used below are as follows. The compounds and fillers used in the following examples and comparative examples were commercially available products, unless the production method was specifically described.

[0118] [Polymerizable monomer (A) having an acidic group] MDP: 10-methacryloyloxydecyl dihydrogen phosphate GPDM: 1,3-dimethacryloyloxypropyl dihydrogen phosphate (glycerol phosphate dimethacrylate) 4-META: 4-methacryloyloxyethyl trimellitic anhydride

[0119] [Photoredox catalyst (B)] TPT: 2,4,6-triphenylpyrylium tetrafluoroborate (Tokyo Chemical Industry Co., Ltd.) MDPT: 4-mesityl-2,6-diphenylpyrylium tetrafluoroborate (synthetic product) Acr ＋ Mes: 9-mesityl-10-methylacridinium tetrafluoroborate (Sigma-Aldrich) DCA: 9,10-dicyanoanthracene (Sigma-Aldrich)

[0120] [Synthesis of MDPT] Under a nitrogen atmosphere, Compound 1 (21.0 g, 84.6 mmol, 1.0 eq) below was mixed with THF (1.68 L), and a 1 M THF solution of 2-mesitylmagnesium bromide (423 ml, 423 mmol, 5.0 eq) was added dropwise, followed by stirring overnight at room temperature (25°C) to obtain a reaction solution. ３ aq. was added and concentrated under reduced pressure. ２ Cl ２ and H ２ The filtrate was allowed to stand and separated into an aqueous layer and an organic layer. ２ Cl ２ The organic layers were combined and washed with NaCl aq. ２ SO ４ The concentrated residue was dried using Et ２ 0 (840 ml), and HBF ４ ・Et２ O (16.5 g, 102 mmol, 1.2 eq) and Et ２ A mixture of 210 ml of MDPT and 1,000 ml of methyl methyl phthalate was added dropwise to the mixture. The mixture was stirred for 1 hour under ice-cooling, and the precipitate was collected by filtration. The filtrate was stirred overnight at room temperature, and the precipitate was collected by filtration again. The collected solids were combined and dried under reduced pressure to obtain a yellow solid, MDPT (19.9 g, yield: 54%).

[0121]

[0122] [Photoredox catalyst (B') other than photoredox catalyst (B)] Eosin Y: 2',4',5',7'-tetrabromofluorescein

[0123] [Maximum absorption wavelength (λ) of the photoredox catalysts (B) and (B')] ｍａｘ ) and molar absorption coefficient (ε) at 400 nm to 500 nm]. For the photoredox catalysts (B) and (B'), the maximum absorption wavelength (λ) of light in the range of 350 to 550 nm was determined. ｍａｘ ) was measured as follows, and the molar extinction coefficient (ε) at 400 nm to 500 nm was calculated as follows. 0.001 mg of the photoredox catalyst (B) or (B') was collected and dissolved in a solvent in a 50 ml measuring flask to prepare a solution. Chloroform was used as the solvent only when the photoredox catalyst was DCA, and methanol was used for other photoredox catalysts. This solution was poured into a quartz glass cell (T-1-UV-10, manufactured by Tosoh Quartz Corporation), and the UV / VIS spectrum was measured using a spectrophotometer U-1900 (manufactured by Hitachi High-Technologies Corporation). Since an accurate spectrum cannot be obtained when the absorbance at the absorption maximum wavelength is 2 or more, when the absorbance at the absorption maximum wavelength is 2 or more, the sample was further diluted and measurement was performed at a concentration such that the absorbance was 2 or less. From the absorption spectrum measured as described above, the maximum absorption wavelength (λ ) in the wavelength range of 350 nm to 550 nm was determined. ｍａｘ) was obtained. In addition, a wavelength near the maximum of light absorption was selected between 400 nm and 500 nm, and the molar absorption coefficient (ε) was calculated from the absorbance (A), the molar concentration c (mol / L) of the sample, and the optical path length l (cm) using the following formula according to the Beer-Lambert law: A (absorbance) = εcl (c: mol / L, l: optical path length = 0.993 cm). The results are shown in Table 1.

[0124] [E of the photoredox catalysts (B) and (B')] Ｓ１ ｒｅｄ and E Ｓ１ ＯＸ For the photoredox catalysts (B) and (B'), the singlet excited state reduction potential E Ｓ１ ｒｅｄ and singlet excited oxidation potential E Ｓ１ ＯＸ was measured as follows. A 0.1 M solution of tetrabutylammonium hexafluorophosphate (TBAPF6, Aldrich) was prepared in anhydrous acetonitrile and added to an electrochemical cell. The solution was degassed by bubbling nitrogen through it for 10 to 15 minutes under ultrasonication. The photoredox catalyst (B) or (B') was added to a concentration of 1 mM to 45 mM. Then, electrochemical measurements were performed using a potentiostat (Bio-Logic, SP-200) and cyclic voltammetry at a sweep rate of 100 mV / s or less, using a working electrode (platinum), a counter electrode (platinum), and a reference electrode (Ag / AgCl, 3M NaCl). The obtained values ​​were converted to SCE by subtracting 0.03 V from the reference electrode (Ag / AgCl, 3M NaCl). The ground-state oxidation potential E ＯＸ １／２ and reduction potential E ｒｅｄ １／２ The above values ​​and the singlet excitation energy (E Ｓ１ ０，０ ) (literature data*) was used to calculate the singlet excited reduction potential (E Ｓ１ ｒｅｄ ) (V vs SCE) and singlet excited oxidation potential (E Ｓ１ ＯＸ ) (V vs SCE) was calculated according to the following formula: Singlet excited state reduction potential: E Ｓ１ ｒｅｄ= E Ｓ１ ０，０ +E ｒｅｄ １／２ Singlet excited oxidation potential: E Ｓ１ ＯＸ = E ＯＸ １／２ -E Ｓ１ ０，０ * Literature data: Chem. Rev. 2016, 116, 10075-10166E Ｓ１ ０，０ The results are shown in Table 1.

[0125]

[0126] [Polymerizable monomer (C) not having an acidic group] [Hydrophilic polymerizable monomer (C-1)] HEMA: 2-hydroxyethyl methacrylate [Hydrophobic polymerizable monomer (C-2)] GDMA: glycerol dimethacrylate 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: 2.6) TEGDMA: triethylene glycol dimethacrylate THF-MA: tetrahydrofurfuryl methacrylate

[0127] [Organic Peroxide (D)] THP: 1,1,3,3-tetramethylbutyl hydroperoxide BPB: t-butyl peroxybenzoate

[0128] [Reducing agent (E)] PyTU: 1-(2-pyridyl)-2-thiourea DMETU: 4,4-dimethylethylenethiourea

[0129] [Phosphine Compound (F)] BPFPP: bis(pentafluorophenyl)phenylphosphine TPFPP: tris(pentafluorophenyl)phosphine TFPP: tris(4-fluorophenyl)phosphine

[0130] [Photopolymerization initiator (G)] CQ: dl-camphorquinone BAPO: bis-(2,4,6-trimethylbenzoyl)phenylphosphine oxide

[0131] [Photopolymerization accelerator] PDE: ethyl 4-(N,N-dimethylamino)benzoate

[0132] [Filler (H)] Surface-treated barium glass: Barium glass (manufactured by Estec Co., Ltd., product code "E-3000") was pulverized in a ball mill to obtain barium glass powder. The average particle size of the obtained barium glass powder was measured using a laser diffraction particle size distribution analyzer (manufactured by Shimadzu Corporation, model "SALD-2300") and was 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 barium glass powder. Silane-treated quartz powder: Quartz (manufactured by MARUWA QUARTZ) was pulverized in a ball mill to obtain a quartz powder with an average particle size of approximately 4.5 μm. 100 parts by mass of this quartz powder was surface-treated with 3 parts by mass of γ-methacryloyloxypropyltrimethoxysilane by a conventional method to obtain a silane-treated quartz 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

[0133] [Transition metal compounds] CuA: copper (II) acetate

[0134] [Polymerization inhibitor] BHT: 2,6-di-t-butyl-4-methylphenol

[0135] [pH adjuster] TTA: triethanolamine

[0136] [Solvent] Purified water Ethanol

[0137] (Examples 1-1 to 1-14, 2-1 to 2-5, Comparative Examples 1-1 to 1-7, 2-1 to 2-3) The components listed in Tables 2 to 4, except for the filler, were mixed at room temperature (25°C) in the blending ratios listed in Tables 2 to 4 to prepare a uniform liquid component. The resulting liquid component was then mixed with the filler to prepare dental adhesive compositions of Example 1 (Examples 1-1 to 1-14), Example 2 (Examples 2-1 to 2-5), Comparative Example 1 (Comparative Examples 1-1 to 1-7), and Comparative Example 2 (Comparative Examples 2-1 to 2-3). These dental adhesive compositions were then evaluated according to the methods described below. The results are shown in Tables 2 to 4. Table 2 shows the evaluation results of bond strength to dentin for Example 1 and Comparative Example 1. Table 3 shows the evaluation results of bond strength to enamel for Example 1 and Comparative Example 1. Table 4 shows the evaluation results of bond strength to dentin for Example 2 and Comparative Example 2.

[0138] [Pretreatment of bovine teeth for bond strength testing] The labial surfaces of bovine mandibular anterior teeth were polished under running water with #80 silicon carbide paper (Nihon Kenshi Co., Ltd.) to expose the flat surface of enamel or dentin. The exposed flat surface was further polished under running water with #1000 silicon carbide paper (Nihon Kenshi Co., Ltd.). After polishing, the surface was dried by air blowing. After drying, a piece of adhesive tape approximately 150 μm thick with a 3 mm diameter circular hole was attached to the smooth surface to determine the adhesive area.

[0139] [Adhesion strength of dental adhesive compositions to bovine teeth immediately after preparation (after 1 day at 37°C)] The dental adhesive compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were applied to the round holes in the adhesive tape of bovine tooth samples that had been pretreated as described above, and after quickly blowing air, light was irradiated for 10 seconds in normal mode using a dental visible light irradiator "Pencure 2000" (manufactured by Morita Seisakusho Co., Ltd.) After that, the round holes were further filled with Clearfil (registered trademark) AP-X (manufactured by Kuraray Noritake Dental Co., Ltd.) as a filling and restorative material (composite resin) in Example 1 and Comparative Example 1, or with Panavia (registered trademark) V5 (manufactured by Kuraray Noritake Dental Co., Ltd.) as a dental resin cement in Example 2 and Comparative Example 2, and the holes were covered with a PP film and pressed together. Subsequently, the material was cured by irradiating light using a PenCure 2000 (manufactured by Morita Seisakusho Co., Ltd.) in normal mode for 20 seconds in the case of Clearfil® AP-X and 10 seconds in the case of Panavia® V5. The surface of the cured filling and restorative material or dental resin cement was sandblasted with 50 μm alumina powder at a pressure of 0.4 MPa. A stainless steel cylindrical rod (7 mm diameter, 2.5 cm length) with dental resin cement "SA Louting® Plus Automix" (manufactured by Kuraray Noritake Dental Co., Ltd.) built up on the surface was placed on the surface so that the center of the circular hole and the center of the stainless steel cylindrical rod were approximately aligned, and the rod was pressed and bonded to prepare test sample A. Five test samples A were prepared. Test sample A was left to stand at 25°C for 30 minutes and then immersed in distilled water. The test sample immersed in distilled water was left to stand in an incubator maintained at 37°C for 24 hours. The tensile bond strength of these test samples to bovine enamel and / or dentin was measured after 24 hours at 37°C. The tensile bond strength was measured using a universal testing machine (Shimadzu Corporation, Autograph "AG-I 100kN") at a crosshead speed of 2 mm / min. The tensile bond strength to bovine enamel and / or dentin shown in the table is the average of the tensile bond strength measurements of five test samples to bovine dentin after 24 hours at 37°C.

[0140] [Adhesion durability of dental adhesive composition to bovine teeth (after TC4000)] Five test samples A prepared according to the same method as above were immersed in distilled water at 37°C for 24 hours, and then subjected to a thermal cycle load of immersion in a water bath at 4°C and a water bath at 60°C for 1 minute each, 4000 times, to prepare adhesion durability test samples (after TC4000). The tensile bond strength of these test samples was measured according to the same method as above. This is the value of adhesion durability (after TC4000). The tensile bond strength values ​​in the table are the average values ​​of the five test samples.

[0141] [Adhesion strength to bovine teeth of dental adhesive compositions subjected to temperature acceleration (after 8 weeks at 50°C) (after 1 day at 37°C)] 5 ml of each of the dental adhesive compositions of Examples 1 and 2 and Comparative Examples 1 and 2 was filled into a product container (light-shielding container) of "Clearfil (registered trademark) Universal Bond Quick ER" (manufactured by Kuraray Noritake Dental Co., Ltd.), and after storing in a dark place at 50°C in a dry atmosphere for 8 weeks, the adhesive strength was measured using this composition in the same manner as in "Adhesion strength to bovine teeth of dental adhesive composition immediately after preparation (after 1 day at 37°C)".

[0142]

[0143] As shown in Tables 2 to 4, the dental adhesive compositions of the Examples exhibited excellent adhesive strength to bovine teeth when used immediately after preparation. Furthermore, when the dental adhesive compositions were used after storage (after 8 weeks at 50°C), the change in adhesive strength to bovine teeth was small compared to when they were used immediately after preparation. Furthermore, the evaluation of adhesive strength after TC4000 in Tables 2 and 3 revealed that the compositions exhibited excellent adhesive durability.

[0144] Comparative Examples 1-1 to 1-6 and 2-1 to 2-3 are dental adhesive compositions that do not contain a photoredox catalyst (B). Comparative Examples 1-1 and 2-1 exhibited lower adhesive strengths than the Examples. Comparative Examples 1-2, 1-3, 1-4, 2-2, and 2-3 are dental adhesive compositions that do not contain a photoredox catalyst (B) and to which an organic peroxide (D) (Comparative Examples 1-2 and 2-2), a reducing agent (E) (Comparative Examples 1-3 and 2-3), or a phosphine compound (F) (Comparative Example 1-4) was added. The dental adhesive compositions of Comparative Examples 1-2 and 2-2 exhibited some effect, but had poor storage stability, and solidification of the compositions was observed after storage (after 8 weeks at 50°C). Therefore, evaluation of adhesive strength was impossible. The dental adhesive compositions of Comparative Examples 1-3, 1-4, and 2-3 did not contain a photoredox catalyst (B), and therefore, the addition of additives did not provide a sufficient adhesion improvement effect. The dental adhesive compositions of Comparative Examples 1-5 and 1-6 had a singlet excited reduction potential E Ｓ１ ｒｅｄ The compositions were those containing a photoredox catalyst (B') that did not satisfy the requirement that the photoredox catalyst (B') had a SCE of 1.5 V or more. These dental adhesive compositions did not exhibit any adhesion-improving effect. Comparative Examples 1-7 did not contain a polymerizable monomer (A) having an acidic group, and were inferior in adhesive strength.

[0145] (Examples 3-1 to 3-2, 4-1 to 4-2, Comparative Examples 3-1 and 4-1) The first and second agents in Table 5 and the components listed in Table 6, except for the filler, were mixed at room temperature (25°C) in the blending ratios listed in Tables 5 and 6 to form a uniform liquid component. The resulting liquid component was then kneaded with the filler to prepare the first and second agents in Table 5 and the dental adhesive compositions listed in Table 6. The dental adhesive compositions (dental self-adhesive resin cements) of Example 3 (Examples 3-1 to 3-2) and Comparative Example 3 (Comparative Example 3-1) consisted of the first and second agents listed in Table 5, which were mixed in equal volumes immediately before use and used in the tests. The dental adhesive compositions (dental adhesive composition composite resins) of Example 4 (Examples 4-1 to 4-2) and Comparative Example 4 (Comparative Example 4-1) were single-component and therefore were used directly in the tests. These dental adhesive compositions were then evaluated according to the methods described below, and the results are shown in Tables 5 and 6.

[0146] [Pretreatment of Bovine Teeth Used in Bond Strength Test] Bovine teeth were pretreated as described above.

[0147] [Adhesion Strength of Immediately Prepared Dental Resin Cement and Dental Self-Adhesive Composite Resin to Bovine Teeth (After 1 Day at 37°C)] The dental adhesive compositions of Examples 3 and 4 and Comparative Examples 3 and 4 were applied to the circular holes in adhesive tape, covered with a PP film, and pressed to define the thickness. The dental adhesive compositions were then irradiated for 10 seconds using a Pencure 2000 (Morita Manufacturing Co., Ltd.) in normal mode. The surface of the cured dental adhesive composition was then sandblasted with 50 μm alumina powder at a pressure of 0.4 MPa. A stainless steel cylindrical rod (7 mm diameter, 2.5 cm length) with dental resin cement "SA Routing® Plus Automix" (Kuraray Noritake Dental Co., Ltd.) built up on the surface was placed on the surface so that the center of the circular hole was approximately aligned with the center of the stainless steel cylindrical rod, and the rod was pressed against the surface to adhere the resin cement. Five test samples B were prepared. Test sample B was left to stand at 25°C for 30 minutes and then immersed in distilled water. The test sample immersed in distilled water was left to stand for 24 hours in an incubator maintained at 37°C. For this test sample, the tensile bond strength to bovine dentin after standing at 37°C for 24 hours was measured. The tensile bond strength to dentin in the table is the average value of the measured tensile bond strengths to bovine dentin for five test samples after standing at 37°C for 24 hours.

[0148] [Adhesion strength to bovine teeth of dental adhesive compositions subjected to temperature acceleration (after 3 weeks at 60°C) (after 1 day at 37°C)] 5 ml of each of the dental adhesive compositions of Examples 3 to 4 and Comparative Examples 3 to 4 was filled into a product container (light-shielding container) of "Clearfil (registered trademark) Universal Bond Quick ER" (manufactured by Kuraray Noritake Dental Co., Ltd.), and after storing in a dark place at 60°C in a dry atmosphere for 3 weeks, the adhesive strength was measured using this composition in the same manner as in "Adhesion strength to bovine teeth of dental adhesive composition immediately after preparation (after 1 day at 37°C)".

[0149]

[0150]

[0151] As shown in Tables 5 and 6, the dental adhesive compositions of the Examples exhibited excellent adhesive strength to bovine teeth when used immediately after preparation. Furthermore, when the dental adhesive compositions were used after storage (after 3 weeks at 60°C), the change in adhesive strength to bovine teeth was small compared to when they were used immediately after preparation.

[0152] Comparative Examples 3-1 and 4-1 are dental adhesive compositions that do not contain the photoredox catalyst (B). These dental adhesive compositions had lower adhesive strength values ​​than the Examples.

[0153] The dental adhesive composition of the present invention can be suitably used in dental treatment for bonding dental prostheses such as dental filling and restorative materials, crowns, inlays, and bridges to tooth structures.

Claims

1. A polymerizable monomer (A) having an acidic group, and a photo-redox catalyst (B) having a singlet excited reduction potential E Ｓ１ ｒｅｄ of 1.5 V vs SCE or more, a dental adhesive composition.

2. The singlet excited oxidation potential E of the photoredox catalyst (B) Ｓ１ оｘ is negative, and the dental adhesive composition according to claim 1.

3. The dental adhesive composition according to claim 1, wherein the photo-redox catalyst (B) is at least one selected from the group consisting of compounds represented by the following formulas (1), (2), and (3). 【Chemical 1】 (In formula (1), R １ , R ２ , R ３ , R ４ , R ５ , R ６ , R ７ , R ８ and R ９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or a halogen atom, and X － is BF ４ － , PF ６ － , ClO ４ － or HSO ４ － .) [Chemical Formula 2] (In formula (2), R １１ , R １３ , R １４ , R １５ , R １６ , and R １８ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R １２ , R １７ , and R １９ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 30 carbon atoms, and X － is BF ４ － , PF ６ － , ClO ４ － or HSO ４ － . ) 【Chemical Formula 3】 (In formula (3), R ２１ , R ２２ , R ２３ and R ２４ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a carboxylic acid group having 1 to 10 carbon atoms and its ester, a hydroxyl group, a cyano group, or a halogen atom.)

4. R in the formula (1) above １ , R ２ and R ３ are each independently an alkyl group having 1 to 4 carbon atoms. The dental adhesive composition according to claim 3

5. R in the above formula (1) １ , R ２ and R ３ are each independently a methyl group, an isopropyl group, or a t-butyl group. The dental adhesive composition according to claim 3.

6. The dental adhesive composition according to claim 1, wherein the absorption spectrum of the photo-redox catalyst (B) includes the range of 400 nm or more and 500 nm or less.

7. The dental adhesive composition according to claim 1, further comprising a polymerizable monomer (C) having no acidic group.

8. The dental adhesive composition according to claim 1, further comprising an organic peroxide (D).

9. The dental adhesive composition according to claim 1, further comprising a reducing agent (E).

10. The dental adhesive composition according to claim 1, further comprising a phosphine compound (F) having an electron-withdrawing group.

11. The dental adhesive composition according to claim 1, further comprising a photoinitiator (G).

12. The dental adhesive composition according to any one of claims 1 to 11, which is a one-component dental bonding material.

13. The dental adhesive composition according to any one of claims 1 to 11, which is a self-adhesive composite resin for dentistry.

14. The dental adhesive composition according to any one of claims 1 to 11, which is a self-adhesive resin cement for dentistry.

15. A kit comprising the dental adhesive composition according to claim 12 and a two-paste dental composition.

16. A kit comprising the dental adhesive composition according to claim 12 and a one-paste dental composition.

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