Polymerizable monomer and polymerizable dental composition including the same

Abstract

To provide a polymerizable monomer that is capable of achieving both the required mechanical strength for dental repair materials and the reduction of polymerization shrinkage stress during curing processes, and a polymerizable dental composition including the same.SOLUTION: The present invention provides a polymerizable monomer with a skeleton represented by general formula (1) and a polymerizable dental composition including the same (where the meanings of the symbols are omitted).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a polymerizable monomer and a dental polymerizable composition using the same. More specifically, the present invention relates to a dental polymerizable composition that can achieve both the mechanical strength required for a dental restorative material and a reduction in polymerization shrinkage stress during hardening, and is highly safe for living organisms. [Background technology]

[0002] In the past, filling materials such as amalgam, inlays and cement have been widely used in the restoration of carious teeth, but in recent years the use of composite resins has been spreading because of their ease of use and superior color tone compared to these filling materials.

[0003] Such composite resin mainly contains a polyfunctional aliphatic acrylic monomer, a bisphenol aromatic compound, an inorganic filler, and a curing catalyst, and is, for example, made of one type of paste. This one type of paste contains a photopolymerization initiator, and is adjusted so that when it is irradiated with a dedicated dental irradiator during dental treatment, the photopolymerization initiator acts to harden it after irradiation.

[0004] The composite resin described above uses a bisphenol-based aromatic compound as an essential component. This bisphenol-based aromatic compound is used as a component to achieve the hardness, abrasion resistance, marginal sealing, etc. required for dental filling materials, but since it is a toxic substance that has recently been recognized as a so-called environmental hormone, it may cause harm to living organisms in the future. In addition, the hardened product of this composite resin has a lower strength than filling materials such as amalgam, and some people question its basic suitability as a dental filling material.

[0005] Composite resins containing fluorene-based polymerizable monomers have been proposed as an alternative to bisphenol-based aromatic compounds (Patent Documents 1 to 3).

[0006] For example, composite resins containing specific fluorene-based polymerizable monomers that can produce cured products with excellent mechanical strength and transparency due to the excellent properties (high heat resistance, high refractive index, etc.) of the fluorene skeleton have been disclosed (Patent Documents 1 and 2). Also, a composite resin containing a specific fluorene-based polymerizable monomer has been disclosed (Patent Document 3) in order to reduce polymerization shrinkage, which is a characteristic of composite resins. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2000-212016 A [Patent Document 2] JP 2008-24637 A [Patent Document 3] International Publication No. 2022 / 112886 Summary of the Invention [Problem to be solved by the invention]

[0008] However, when the present inventors used the composition according to Patent Document 3, it was found that there was room for improvement in achieving both the mechanical strength required for a dental restorative material and the reduction of polymerization shrinkage stress during hardening.

[0009] Therefore, an object of the present invention is to provide a polymerizable monomer that can achieve both the mechanical strength required for a dental restorative material and a reduction in polymerization shrinkage stress during hardening, and a dental polymerizable composition using the same. [Means for solving the problem]

[0010] As a result of extensive investigations, the present inventors have found that a polymerizable composition containing a specific fluorene-based polymerizable monomer can solve the above problems, and have completed the present invention through further investigations.

[0011] That is, the present invention includes the following inventions. [1] A polymerizable monomer having a skeleton represented by the following general formula (1): [ka] (In the formula, * represents a bond, R 1 ~R 6 each independently represents a substituent, R 7 , and R 8 each independently represents a hydrogen atom or an organic group; X 1 , and X 2 each independently represents an oxygen atom, a sulfur atom, or NR 9 (R 9 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 each independently represents an aromatic hydrocarbon ring; k and m each independently represent an integer of 0 to 4; n, p, q, and r each independently represent an integer of 0 or 1 or more. [2] The polymerizable monomer according to [1], wherein at least one of the two * in the general formula (1) is a polymerizable monomer bonded at the * site of a functional group represented by the following general formula (2): [ka] (In the formula, R 10 represents a hydrogen atom or a methyl group, R 11 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a carbamoyl group, a (meth)acryloyloxy group, a (meth)acryloylpoly(oxyethylene) group, or a (meth)acryloylpoly(oxyethylene)carbamoyl group; X 3 is an oxygen atom, a sulfur atom, or NR 12 (R 12 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; s is an integer of 1 to 15, t is 0 or 1, and w is an integer of 0 to 6. [3] Ring Z 1, ring Z 2 , ring Z 3 , and ring Z 4 is a benzene ring or a naphthalene ring. [4]X 1 , and X 2 is an oxygen atom. [5] R 1 ~R 6 are each independently an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms. [6]X 3 is an oxygen atom. [7] A composition comprising a radical polymerizable monomer (A) and a polymerization initiator (B), A dental polymerizable composition, wherein the radical polymerizable monomer (A) comprises a radical polymerizable monomer (a-1) which is the polymerizable monomer according to any one of [1] to [6]. [8] The dental polymerizable composition according to [7], further comprising a polymerization accelerator (C). [9] The dental polymerizable composition according to [7] or [8], further comprising a filler (D).

[10] The dental polymerizable composition according to any one of [7] to [9], wherein the content of the radical polymerizable monomer (a-1) is 0.1 to 10 mass% in a total of 100 mass% of the dental polymerizable composition.

[11] The dental polymerizable composition according to any one of [7] to

[10] , wherein the radical polymerizable monomer (A) further contains a radical polymerizable monomer (a-2) other than the radical polymerizable monomer (a-1).

[12] The dental polymerizable composition according to

[11] , wherein the content of the radical polymerizable monomer (a-2) is 10 to 30 mass % in a total of 100 mass % of the dental polymerizable composition.

[13] The dental polymerizable composition according to any one of [7] to

[12] , wherein the content of the polymerization initiator (B) is 0.001 to 10 parts by mass per 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[14] The dental polymerizable composition according to any one of [7] to

[13] , wherein the content of the polymerization accelerator (C) is 0.001 to 10 parts by mass per 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[15] A dental composite resin comprising the dental polymerizable composition according to any one of [7] to

[14] .

[16] A self-adhesive composite resin comprising the dental polymerizable composition according to any one of [7] to

[14] .

[17] A dental adhesive comprising the dental polymerizable composition according to any one of [7] to

[14] .

[18] A dental cement comprising the dental polymerizable composition according to any one of [7] to

[14] . Effect of the Invention

[0012] According to the present invention, it is possible to provide a polymerizable monomer that can achieve both the mechanical strength required for a dental restorative material and a reduction in polymerization shrinkage stress during hardening, and a dental polymerizable composition using the same. Furthermore, according to the present invention, the dental polymerizable composition does not contain a bisphenol-based aromatic compound, and therefore is highly safe for living organisms. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] The polymerizable monomer of the present invention is a polymerizable monomer having a skeleton represented by general formula (1). Hereinafter, the polymerizable monomer having a skeleton represented by general formula (1) can be referred to as a radically polymerizable monomer (a-1).

[0014] In this specification, "(meth)acrylic" is a general term for methacrylic and acrylic, and the same applies to similar expressions (such as "(meth)acrylic acid" and "(meth)acrylonitrile"). In this specification, the upper and lower limit values ​​of the numerical ranges (contents of each component, values ​​calculated from each component, and each physical property, etc.) can be appropriately combined. In addition, in this specification, each embodiment can be modified by appropriately combining a part or all of them.

[0015] The reason why the dental polymerizable composition containing the polymerizable monomer having a skeleton represented by the general formula (1) of the present invention can achieve both the mechanical strength required for a dental restorative material and the reduction in polymerization shrinkage stress during hardening is not clear, but is presumed to be as follows. The polymerizable monomer having a skeleton represented by the general formula (1) of the present invention has a three-dimensional structure, and therefore the molecular space occupying volume is large. In addition, compared with the fluorene-based monomers of the prior art (Patent Documents 1 to 3), the polymerizable monomer has a bulkier structure due to the inclusion of more aromatic rings in the side chains, and is therefore considered to be able to more effectively suppress shrinkage during polymerization. In addition, it is presumed that the polymerizable monomer has a strong skeleton containing a fluorene skeleton and a large number of aromatic rings, which is why the cured product was able to maintain high mechanical strength.

[0016] An example of an embodiment is a dental polymerizable composition comprising a radical polymerizable monomer (A) and a polymerization initiator (B), wherein the radical polymerizable monomer (A) comprises a radical polymerizable monomer (a-1). Each component used in the dental polymerizable composition of the present invention will be described below.

[0017] <Radically polymerizable monomer (a-1)> By blending the radically polymerizable monomer (a-1) in the dental polymerizable composition, it is possible to achieve both the mechanical strength required for a dental restorative material and a reduction in polymerization shrinkage stress during hardening. As described above, the radical polymerizable monomer (a-1) has a three-dimensional structure, and therefore the molecular space occupied volume is large. In addition, since the side chain contains more aromatic rings than those of the conventional technology, the structure is even bulkier. Therefore, the shrinkage during polymerization of dental restorative materials can be more effectively suppressed, and the radical polymerizable monomer (a-1) has an excellent polymerization shrinkage suppressing effect in dental applications.

[0018] The radical polymerizable monomer (a-1) used in the present invention includes a polymerizable monomer having a skeleton represented by the following general formula (1). [ka] (In the formula, * represents a bond, R 1 ~R 6 each independently represents a substituent, R 7 , and R 8 each independently represents a hydrogen atom or an organic group; X 1 , and X 2 each independently represents an oxygen atom, a sulfur atom, or NR 9 (R 9 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 each independently represents an aromatic hydrocarbon ring; k and m each independently represent an integer of 0 to 4; n, p, q, and r each independently represent an integer of 0 or 1 or more.

[0019] Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 The aromatic hydrocarbon ring preferably has 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, further preferably 6 to 18 carbon atoms, and particularly preferably 6 to 14 carbon atoms.

[0020] Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 Examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, an anthracene ring, and a pyrene ring. A benzene ring, a naphthalene ring, or an anthracene ring is preferable, a benzene ring or a naphthalene ring is more preferable, and a benzene ring is even more preferable.

[0021] X 1 , and X 2 each independently represents an oxygen atom or NR 9(R 9 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.) is preferable, and from the viewpoints of being superior in mechanical strength and the effect of reducing polymerization shrinkage stress, it is more preferable that it is an oxygen atom.

[0022] R 1 ~R 6 Examples of the substituent include a hydrocarbon group, an alkoxy group, a halogen atom (a fluorine atom, a chlorine atom, a bromine atom, an iodine atom), a hydroxyl group, a mercapto group, and the like, with a hydrocarbon group being preferred.

[0023] R 1 ~R 6 Examples of the hydrocarbon group include an alkyl group, an aryl group, an aralkyl group, and an alkenyl group. The alkyl group may be linear, branched, or cyclic, with linear and branched groups being preferred. The alkyl group preferably has 1 to 20 carbon atoms, more preferably 1 to 12 carbon atoms, further preferably 1 to 8 carbon atoms, and particularly preferably 1 to 6 carbon atoms. Examples of the alkyl group 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, an n-dodecyl group, an n-tridecyl group, an n-tetradecyl group, an n-pentadecyl group, an n-hexadecyl group, an n-heptadecyl group, an n-octadecyl group, an n-octadecyl group, an n-nonadecyl group, and an n-icosyl group. The aryl group preferably has 6 to 30 carbon atoms, more preferably 6 to 20 carbon atoms, further preferably 6 to 18 carbon atoms, and particularly preferably 6 to 14 carbon atoms. R 1 ~R 6Examples of the aryl group include a phenyl group, a biphenyl group, an indenyl group, a naphthyl group, an anthryl group, a phenanthryl group, a fluorenyl group, a pyrenyl group, a tolyl group, a xylyl group, a trimethylphenyl group, an ethylphenyl group, an isopropylphenyl group, and a tetramethylphenyl group. A phenyl group or a naphthyl group is preferable, and a phenyl group is more preferable. The aralkyl group preferably has 7 to 30 carbon atoms, more preferably 7 to 20 carbon atoms, further preferably 7 to 18 carbon atoms, and particularly preferably 7 to 13 carbon atoms. Examples of the aralkyl group include a benzyl group, a methylbenzyl group, a phenethyl group, a phenylpropyl group, a naphthylmethyl group, an indenylmethyl group, and a biphenylmethyl group. The alkenyl group may be either linear or branched. The alkenyl group preferably has 2 to 15 carbon atoms, more preferably 2 to 12 carbon atoms, further preferably 2 to 8 carbon atoms, and particularly preferably 2 to 6 carbon atoms. Examples of alkenyl groups include vinyl groups, 1-propenyl groups, 2-propenyl groups, isopropenyl groups, 3-butenyl groups, 2-butenyl groups, 1-butenyl groups, 1-methyl-2-propenyl groups, 1-methyl-1-propenyl groups, 1-ethyl-1-ethenyl groups, 2-methyl-2-propenyl groups, 2-methyl-1-propenyl groups, 3-methyl-2-butenyl groups, and 4-pentenyl groups. The alkoxy group may be either linear or branched. The alkoxy group preferably has 1 to 15 carbon atoms, more preferably 1 to 12 carbon atoms, further preferably 1 to 8 carbon atoms, and particularly preferably 1 to 6 carbon atoms. Examples of alkoxy groups include a methoxy group, an ethoxy group, an n-propoxy group, an isopropoxy group, an n-butoxy group, an n-pentyloxy group, an n-hexyloxy group, an n-heptyloxy group, an n-octyloxy group, a methoxymethoxy group, a 1-ethoxyethoxy group, a 2-trimethylsilylethoxy group, and a 2-trimethylsilylethoxymethoxy group.

[0024] In some embodiments, R 1 ~R 6 is preferably each independently an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms.

[0025] k and m are each independently preferably an integer of 0 to 3, more preferably an integer of 0 to 2, further preferably 0 or 1, and particularly preferably 0. In other words, the benzene ring contained in the fluorene skeleton may have a substituent or may be unsubstituted.

[0026] Each of n, p, q and r is preferably an integer of 0 to 4, more preferably an integer of 0 to 2, further preferably 0 or 1, and particularly preferably 0. In other words, ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 may have a substituent or may be unsubstituted.

[0027] In another embodiment, k, m, n, p, q and r are preferably 0 from the viewpoint of superior mechanical strength and effect of reducing polymerization shrinkage stress.

[0028] R 7 , and R 8Examples of the organic group include a linear or branched acyl group having 1 to 8 carbon atoms, a linear or branched alkyl group having 1 to 8 carbon atoms, a linear or branched alkoxy group having 1 to 8 carbon atoms, a cycloalkyl group having 2 to 20 carbon atoms, an aralkyl group having 7 to 30 carbon atoms, and a functional group represented by general formula (2). The acyl group preferably has 1 to 7 carbon atoms, more preferably 1 to 6 carbon atoms, further preferably 1 to 4 carbon atoms, and particularly preferably 1 to 3 carbon atoms. Examples of the acyl group include aliphatic acyl groups such as a formyl group, an acetyl group, a propionyl group, a 2-methylpropionyl group, a 2,2-dimethylpropionyl group, and a 2-ethylhexanoyl group. The alkyl group preferably has 1 to 8 carbon atoms, more preferably 1 to 7 carbon atoms, further preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms. The alkyl group is R 1 ~R 6 Examples of the alkyl group include those having 1 to 8 carbon atoms, which are similar to those exemplified above as the alkyl group. The alkoxy group preferably has 1 to 8 carbon atoms, more preferably 1 to 7 carbon atoms, further preferably 1 to 6 carbon atoms, and particularly preferably 1 to 4 carbon atoms. The alkoxy group is R 1 ~R 6 The alkoxy groups are the same as those exemplified above and have 1 to 8 carbon atoms. The cycloalkyl group preferably has 3 to 18 carbon atoms, more preferably 4 to 12 carbon atoms, further preferably 5 to 10 carbon atoms, and particularly preferably 6 to 8 carbon atoms. Examples of the cycloalkyl group include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a cyclooctyl group. The aralkyl group is R 1 ~R 6 Examples of the aralkyl group include the same as those exemplified above for the aralkyl group. The functional group represented by general formula (2) is as described later.

[0029] R 7 , and R 8 are each independently preferably a hydrogen atom or a linear or branched alkyl group having 1 to 8 carbon atoms, and more preferably a hydrogen atom.

[0030] In the present invention, it is preferable that at least one of the two * in the general formula (1) is a polymerizable monomer bonded at the * site of a functional group represented by the following general formula (2), and it is more preferable that both of the two * are polymerizable monomers bonded at the * site of a functional group represented by the following general formula (2). In the case of a polymerizable monomer in which two * in the above general formula (1) are bonded at the * sites of functional groups represented by the following general formula (2), the functional groups represented by general formula (2) may be the same or different. When only one of the two * in the general formula (1) is a polymerizable monomer bonded at the * site of the functional group represented by general formula (2), the other * may be bonded to a hydrogen atom or a (meth)acryloyl group. [ka] (In the formula, R 10 represents a hydrogen atom or a methyl group, R 11 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a carbamoyl group, a (meth)acryloyloxy group, a (meth)acryloylpoly(oxyethylene) group, or a (meth)acryloylpoly(oxyethylene)carbamoyl group; X 3 is an oxygen atom, a sulfur atom, or NR 12 (R 12 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; s is an integer of 1 to 15, t is 0 or 1, and w is an integer of 0 to 6.

[0031] In some embodiments, t is preferably 1.

[0032] s is preferably 1 to 10, more preferably 1 to 5, further preferably 1 to 3, and particularly preferably 1 or 2, from the viewpoint of being superior in mechanical strength and the effect of reducing polymerization shrinkage stress.

[0033] w is preferably 0 to 4, more preferably 0 to 3, further preferably 1 or 3, and particularly preferably 1 or 2.

[0034] In some embodiments, R 10 More preferably, is a methyl group.

[0035] In the general formula (2), R 11 is preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a (meth)acryloylpoly(oxyethylene) group, or a (meth)acryloylpoly(oxyethylene)carbamoyl group, and more preferably a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a (meth)acryloylpoly(oxyethylene)carbamoyl group.

[0036] R 11 As the alkyl group having 1 to 8 carbon atoms, R 1 ~R 6 Examples of the alkyl group include those having 1 to 8 carbon atoms, which are similar to those exemplified above as the alkyl group. The number of repeating units of the oxyethylene group in the (meth)acryloylpoly(oxyethylene) group is preferably 2 or more, and more preferably 3 or more. The number of repeating units of the oxyethylene group in the (meth)acryloylpoly(oxyethylene)carbamoyl group is preferably 2 or more, and more preferably 3 or more.

[0037] In the general formula (2), X 3 is an oxygen atom or NR 12 (R 12 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms.) is preferable, and an oxygen atom is more preferable. R 12 As the alkyl group having 1 to 8 carbon atoms, R 1 ~R 6Examples of the alkyl group include those having 1 to 8 carbon atoms, which are similar to those exemplified above as the alkyl group.

[0038] In a preferred embodiment, in the general formula (2), R 11 represents a hydrogen atom, and X 3 is an oxygen atom, t is 1, s is 1 to 5, and w is 1 to 3.

[0039] In another preferred embodiment, the polymerizable monomer has a skeleton represented by general formula (1), in which t is 0 and w is 0 in general formula (2).

[0040] In a preferred embodiment, in the general formula (2), X 3 is an oxygen atom, t is 0, s is 1 to 5, and w is 1 to 3.

[0041] Examples of the functional group represented by general formula (2) include those shown below. [ka]

[0042] The polymerizable monomer (a-1) can be synthesized in accordance with a known method. Examples of methods for producing the polymerizable monomer (a-1) include those described in International Publication No. WO 2022 / 112886 and Dental materials 34 (2018) 1003-1013. The polymerizable monomer (a-1) can be produced, for example, by reacting a compound having a fluorene skeleton (e.g., 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene) with a (meth)acrylic compound having an isocyanate group or acryloyl chloride. Compounds having a fluorene skeleton can be synthesized according to known methods. For example, bis(hydroxyphenyl)fluorenes obtained by a method of reacting fluorenones with phenols in the presence of hydrogen chloride gas and mercaptocarboxylic acid (J. Appl. Polym. Sci., 27(9), 3289,1982) can be further reacted with p-chloronitrobenzene by the method described in Journal of Materials Science volume 54, 10560-10569 (2019), and then the nitro group can be reduced. In addition, a commercially available product can also be used as the compound having a fluorene skeleton.

[0043] Specific examples of the polymerizable monomer (a-1) are not particularly limited, but suitable examples include the following.

[0044] [ka]

[0045] [ka]

[0046] [ka]

[0047] [ka]

[0048] [ka]

[0049] [ka]

[0050]

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[0051]

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[0061] [ka]

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[0065] [ka]

[0066] [ka]

[0067] [ka]

[0068] [ka]

[0069] The content of the radical polymerizable monomer (a-1) in the dental polymerizable composition is preferably 0.1 to 10 mass%, more preferably 1 to 8 mass%, based on 100 mass% of the total dental polymerizable composition from the viewpoints of mechanical strength and polymerization shrinkage stress, and further preferably 2 to 5 mass% from the viewpoint of superior polymerization shrinkage stress. In a preferred embodiment, the content of the radical polymerizable monomer (a-1) in the dental polymerizable composition is preferably 1 to 40 mass%, more preferably 2 to 35 mass%, and further preferably 5 to 30 mass% in terms of superior polymerization shrinkage stress, relative to 100 mass% of the total of the polymerizable monomers contained in the dental polymerizable composition, from the viewpoints of mechanical strength and polymerization shrinkage stress.

[0070] <Radical polymerizable monomer (a-2)> A preferred embodiment of the present invention is a dental polymerizable composition in which the radical polymerizable monomer (A) further contains a radical polymerizable monomer (a-2) other than the radical polymerizable monomer (a-1) (hereinafter, simply referred to as "radical polymerizable monomer (a-2)"). The radical polymerizable monomer (a-2) in the present invention includes a hydrophobic monomer (a-2-1) having no acidic group and having a solubility in water at 25°C of less than 10% by mass (hereinafter, sometimes simply referred to as "hydrophobic monomer (a-2-1)"); a hydrophilic monomer (a-2-2) having no acidic group and having a solubility in water at 25°C of 10% by mass or more (hereinafter, sometimes simply referred to as "hydrophilic monomer (a-2-2)"); and a monomer (a-2-3) having an acidic group (hereinafter, sometimes simply referred to as "hydrophilic monomer (a-2-3)"). The radical polymerizable monomer (a-2) may be used alone or in combination of two or more kinds.

[0071] Hydrophobic monomers without acidic groups (a-2-1) As the hydrophobic monomer (a-2-1), a radical polymerizable monomer having no acidic group and a polymerizable group is preferred, and from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophobic monomer (a-2-1) means a monomer that does not have an acidic group and has a solubility of less than 10 mass % in water at 25° C. The hydrophobic monomer is further divided into a monofunctional hydrophobic monomer (a-2-1a) that is monofunctional, and a polyfunctional hydrophobic monomer (a-2-1b). Examples of the monofunctional hydrophobic monomer (a-2-1a) include monofunctional monomers of aromatic compounds and monofunctional monomers of aliphatic compounds. Examples of the polyfunctional hydrophobic monomer (a-2-1b) include crosslinkable monomers such as aromatic bifunctional monomers, aliphatic bifunctional monomers, and trifunctional or higher monomers. The hydrophobic monomer (a-2-1) may be used alone or in combination of two or more kinds.

[0072] Monofunctional hydrophobic monomer (a-2-1a) Examples of the monofunctional hydrophobic monomer (a-2-1a) include (meth)acrylate monomers, (meth)acrylamide monomers, etc. The monofunctional hydrophobic monomer (a-2-1a) may be used alone or in combination of two or more kinds.

[0073] Examples of the monofunctional hydrophobic monomer (a-2-1a) include aliphatic compound-based monofunctional (meth)acrylate monomers such as n-stearyl methacrylate; aliphatic compound-based monofunctional (meth)acrylate monomers containing ether bonds such as butoxydiethylene glycol methacrylate and methoxypolyethylene glycol methacrylate (average number of moles of oxyethylene groups added: 9); alicyclic compound-based monofunctional (meth)acrylate monomers such as cyclohexyl methacrylate, isobornyl methacrylate and dicyclopentanyl methacrylate; monofunctional (meth)acrylate monomers having an aromatic ring group such as benzyl (meth)acrylate, phenoxybenzyl (meth)acrylate and 2-phenoxyethyl (meth)acrylate; and (meth)acrylate monomers containing a heterocyclic group (e.g., a cyclic ether group) such as tetrahydrofurfuryl (meth)acrylate. As the monofunctional (meth)acrylate monomer having an aromatic ring group, one having one or two phenyl groups is preferred. As the (meth)acrylate monomer containing a heterocyclic group, one having one or two heterocyclic groups (for example, a cyclic ether group, etc.) is preferable. Among these, from the viewpoints of mechanical strength and the effect of reducing polymerization shrinkage stress, tetrahydrofurfuryl methacrylate (commonly known as THF-MA), benzyl methacrylate (commonly known as BEMA), phenoxybenzyl methacrylate (commonly known as POB-MA), and 2-phenoxyethyl methacrylate (commonly known as PEMA) are preferred.

[0074] · Multifunctional hydrophobic monomer (a-2-1b) Examples of the polyfunctional hydrophobic monomer (a-2-1b) include bifunctional hydrophobic monomers of aromatic compounds, bifunctional hydrophobic monomers of aliphatic compounds, and trifunctional or higher hydrophobic monomers. The polyfunctional hydrophobic monomer (a-2-1b) may be used alone or in combination of two or more kinds.

[0075] Examples of the aromatic bifunctional hydrophobic monomer include 2,2-bis((meth)acryloyloxyphenyl)propane, 2,2-bis[4-(2-hydroxy-3-(meth)acryloyloxypropoxy)phenyl]propane, 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypolyethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane, and the like. 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 the like. Among these, from the viewpoints of mechanical strength, refractive index adjustment, and handling properties, 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)phenyl]propane (commonly known as "Bis-GMA"), 2,2-bis(4-(meth)acryloyloxyethoxyphenyl)propane, 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles added of ethoxy groups: 2.6, commonly known as "D-2.6E"), 2,2-bis(4-(meth)acryloyloxydiethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytriethoxyphenyl)propane, 2,2-bis(4-(meth)acryloyloxytetraethoxyphenyl)propane, and 2,2-bis(4-(meth)acryloyloxypentaethoxyphenyl)propane are preferred.

[0076] Examples of the aliphatic compound-based bifunctional hydrophobic monomer include glycerol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, and the like. Examples of such compounds include ol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl) di(meth)acrylate, N-methacryloyloxyethyl acrylamide (commonly known as "MAEA"), N-methacryloyloxypropyl acrylamide, N-methacryloyloxybutyl acrylamide, N-(1-ethyl-(2-methacryloyloxy)ethyl)acrylamide, and N-(2-(2-methacryloyloxyethoxy)ethyl)acrylamide. Among these, triethylene glycol diacrylate, triethylene glycol dimethacrylate (commonly known as "3G"), neopentyl glycol di(meth)acrylate, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl)dimethacrylate (commonly known as "UDMA"), 1,10-decanediol dimethacrylate (commonly known as "DD"), and 2,2,4-trimethylhexamethylene bis(2-carbamoyloxyethyl)dimethacrylate are preferred from the viewpoint of mechanical strength. From the viewpoint of polymerization shrinkage stress, 1,2-bis(3-methacryloyloxy-2-hydroxypropoxy)ethane, UDMA, and DD are preferred. From the viewpoint of adhesion to tooth structure, particularly dentin, MAEA and N-methacryloyloxypropylacrylamide are preferred.

[0077] Examples of the trifunctional or higher hydrophobic monomer include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolmethane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetra(meth)acrylate, 1,7-diacryloyloxy-2,2,6,6-tetra(meth)acryloyloxymethyl-4-oxaheptane, etc. Among these, N,N-(2,2,4-trimethylhexamethylene)bis[2-(aminocarboxy)propane-1,3-diol]tetramethacrylate is preferred from the viewpoint of mechanical strength.

[0078] Among the above hydrophobic monomers (a-2-1), from the viewpoint of mechanical strength, bifunctional hydrophobic monomers of aromatic compounds, and bifunctional hydrophobic monomers and monofunctional hydrophobic monomers of aliphatic compounds are preferred. As the aromatic compound-based bifunctional monomer, Bis-GMA and D-2.6E are preferred. As the aliphatic compound-based bifunctional monomer, 3G, neopentyl glycol di(meth)acrylate, UDMA, DD, and MAEA are preferred, and as the monofunctional hydrophobic monomer, THF-MA, BEMA, POB-MA, and PEMA are preferred.

[0079] Among the above hydrophobic monomers (a-2-1), when used as a dental polymerizable composition, from the viewpoint of mechanical strength, hydrophobic monomers having no hydroxyl groups (monofunctional hydrophobic monomers having no hydroxyl groups, bifunctional hydrophobic monomers of aromatic compounds having no hydroxyl groups, and bifunctional hydrophobic monomers of aliphatic compounds having no hydroxyl groups) are preferred, D-2.6E, DD, UDMA, MAEA, THF-MA, BEMA, POB-MA, and PEMA are more preferred, and D-2.6E, DD, MAEA, and THF-MA are even more preferred.

[0080] The hydrophobic monomer (a-2-1) may be used alone or in combination of two or more kinds. The content of the hydrophobic monomer (a-2-1) in the dental polymerizable composition is preferably 5 to 98 mass%, more preferably 10 to 50 mass%, and even more preferably 10 to 30 mass%, based on 100 mass% of the total dental polymerizable composition. By controlling the content of the hydrophobic monomer (a-2-1) to be equal to or less than the upper limit value described below, it is easy to prevent the wettability of the dental polymerizable composition to tooth substance from decreasing, resulting in a decrease in adhesive strength, and by controlling the content to be equal to or more than the lower limit value described above, it is easy to obtain the desired mechanical strength of the cured product. In a preferred embodiment, the content of the hydrophobic monomer (a-2-1) in the dental polymerizable composition is preferably 50 to 98 mass%, more preferably 55 to 95 mass%, based on 100 mass% of the total polymerizable monomers contained in the dental polymerizable composition from the viewpoint of mechanical strength, and even more preferably 60 to 92 mass% from the viewpoint of superior polymerization shrinkage stress.

[0081] Hydrophilic monomers without acidic groups (a-2-2) In one embodiment, the hydrophilic monomer (a-2-2) can improve the wettability of the dental polymerizable composition to tooth structure and the permeability into tooth structure (enamel and / or dentin), thereby improving the adhesive strength to tooth structure. As the hydrophilic monomer (a-2-2), a radical polymerizable monomer having no acidic group and a polymerizable group is preferred, and from the viewpoint of ease of radical polymerization, the polymerizable group is preferably a (meth)acryloyloxy group and / or a (meth)acrylamide group. The hydrophilic monomer (a-2-2) means a monomer which does not have an acidic group and has a solubility in water at 25°C of 10% by mass or more, preferably a monomer which has a solubility of 30% by mass or more, and more preferably a monomer which can be dissolved in water at any ratio at 25°C. The hydrophilic monomer is preferably one having a hydrophilic group such as a hydroxyl group, an oxymethylene group, an oxyethylene group, an oxypropylene group, or an amide group.

[0082] Examples of the hydrophilic monomer (a-2-2) include hydrophilic monofunctional (meth)acrylate monomers such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 1,3-dihydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, 2-((meth)acryloyloxy)ethyltrimethylammonium chloride, and polyethylene glycol di(meth)acrylate (average number of moles of oxyethylene groups added: 9 or more); Examples of the hydrophilic monofunctional (meth)acrylamide monomers include N-methylol (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N,N-bis(2-hydroxyethyl) (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-ethoxymethyl (meth)acrylamide, diacetone (meth)acrylamide, 4-(meth)acryloylmorpholine, N-trihydroxymethyl-N-methyl (meth)acrylamide, N,N-dimethylacrylamide, and N,N-diethylacrylamide.

[0083] Among these hydrophilic monomers (a-2-2), from the viewpoint of adhesion to tooth structure, 2-hydroxyethyl (meth)acrylate, 2,3-dihydroxypropyl (meth)acrylate, and hydrophilic monofunctional (meth)acrylamide monomers are preferred, and 2-hydroxyethyl (meth)acrylate, N,N-dimethylacrylamide, and N,N-diethylacrylamide are more preferred. The hydrophilic monomer (a-2-2) may be used alone or in combination of two or more kinds.

[0084] The content of the hydrophilic monomer (a-2-2) in the dental polymerizable composition is preferably 0 to 98 mass%, more preferably 0 to 50 mass%, and even more preferably 0 to 30 mass% in the total 100 mass% of the dental polymerizable composition. The content of the hydrophilic monomer (a-2-2) may be 0 mass% in the total 100 mass% of the dental polymerizable composition. When the content of the hydrophilic monomer (a-2-2) in the dental polymerizable composition is equal to or more than the lower limit, a sufficient improvement in adhesive strength is easily obtained, and when the content is equal to or less than the upper limit, the desired mechanical strength of the cured product is easily obtained.

[0085] From the viewpoint of the properties of the dental polymerizable composition, the content of the radical polymerizable monomer (a-2) in the dental polymerizable composition is preferably 5 to 98 mass%, more preferably 10 to 50 mass%, and even more preferably 10 to 30 mass%, based on 100 mass% of the total of the dental polymerizable composition. From the viewpoints of adhesion to tooth substance and water absorption and solubility of the cured product, the mass ratio of the hydrophobic monomer (a-2-1) to the hydrophilic monomer (a-2-2) is preferably hydrophobic monomer (a-2-1):hydrophilic monomer (a-2-2) = 1:0 to 1:2, more preferably 1:0 to 1:1, and even more preferably 1:0 to 2:1.

[0086] <Monomer having an acidic group (a-2-3)> In one embodiment, when the dental polymerizable composition is applied to a self-adhesive composite resin or a dental adhesive, it is preferable that the dental polymerizable composition contains a monomer (a-2-3) having an acidic group from the viewpoint of adhesion to tooth structure. In addition, by blending the monomer (a-2-3) having an acidic group, excellent sealing properties for cavities can be imparted. A radically polymerizable monomer is preferably used in the dental polymerizable composition. Specific examples of the radically polymerizable monomer in the monomer (a-2-3) having an acidic group include (meth)acrylate-based monomers, (meth)acrylamide-based monomers, α-cyanoacrylic acid, (meth)acrylic acid, α-halogenated acrylic acid, crotonic acid, cinnamic acid, sorbic acid, maleic acid, itaconic acid, and other esters, vinyl esters, vinyl ethers, mono-N-vinyl derivatives, and styrene derivatives. Among these, (meth)acrylate-based monomers and (meth)acrylamide-based monomers are preferred from the viewpoint of curability.

[0087] The monomer (a-2-3) having an acidic group used in the present invention may be, for example, a monomer having at least one acidic group such as a phosphoric acid group, a pyrophosphoric acid group, a thiophosphoric acid group, a phosphonic acid group, a carboxylic acid group, or a sulfonic acid group. The monomer (a-2-3) having an acidic group may be used alone or in combination of two or more. Specific examples of the monomer (a-2-3) having an acidic group are shown below.

[0088] Examples of monomers having a phosphate group include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, and 8-(meth)acryloyloxyoctyl. Dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, bis[2-(meth)acryloyloxy] acryloyloxyethyl]hydrogen phosphate, bis[4-(meth)acryloyloxybutyl]hydrogen phosphate, bis[6-(meth)acryloyloxyhexyl]hydrogen phosphate, bis[8-(meth)acryloyloxyoctyl]hydrogen phosphate, bis[9-(meth)acryloyloxynonyl]hydrogen phosphate, bis[10-(meth)acryloyloxydecyl]hydrogen phosphate, 1,3-di(meth)acryloyloxypropyl dihydrogen Examples of suitable phosphates include 2-(meth)acryloyloxyethylphenyl hydrogen phosphate, 2-(meth)acryloyloxyethyl-(2-bromoethyl)hydrogen phosphate, 2-methacryloyloxyethyl-(4-methoxyphenyl)hydrogen phosphate, 2-methacryloyloxypropyl-(4-methoxyphenyl)hydrogen phosphate, and acid chlorides, alkali metal salts, and amine salts thereof, and a monomer having a divalent phosphoric acid group having an alkylene group having 6 to 12 carbon atoms is preferred.One preferred embodiment is a dental polymerizable composition in which the monomer (a-2-3) having an acidic group includes a monomer having a divalent phosphate group having an alkylene group having 6 to 12 carbon atoms.

[0089] Examples of monomers having a pyrophosphate group include bis[2-(meth)acryloyloxyethyl]pyrophosphate, bis[4-(meth)acryloyloxybutyl]pyrophosphate, bis[6-(meth)acryloyloxyhexyl]pyrophosphate, bis[8-(meth)acryloyloxyoctyl]pyrophosphate, bis[10-(meth)acryloyloxydecyl]pyrophosphate, and acid chlorides, alkali metal salts, and amine salts thereof.

[0090] Examples of monomers having a thiophosphate group include 2-(meth)acryloyloxyethyl dihydrogen thiophosphate, 3-(meth)acryloyloxypropyl dihydrogen thiophosphate, 4-(meth)acryloyloxybutyl dihydrogen thiophosphate, 5-(meth)acryloyloxypentyl dihydrogen thiophosphate, 6-(meth)acryloyloxyhexyl dihydrogen thiophosphate, 7-(meth)acryloyloxyheptyl dihydrogen thiophosphate, and 8-(meth)acryloyloxyoctyl dihydrogen thiophosphate. Examples of suitable acryloyloxyalkyl groups include acryloyloxyalkyl groups, 9-(meth)acryloyloxynonyl dihydrogen thiophosphate, 10-(meth)acryloyloxydecyl dihydrogen thiophosphate, 11-(meth)acryloyloxyundecyl dihydrogen thiophosphate, 12-(meth)acryloyloxydodecyl dihydrogen thiophosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen thiophosphate, 20-(meth)acryloyloxyicosyl dihydrogen thiophosphate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0091] Examples of monomers having a phosphonic acid group include 2-(meth)acryloyloxyethyl phenyl phosphonate, 5-(meth)acryloyloxypentyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl-3-phosphonopropionate, 10-(meth)acryloyloxydecyl-3-phosphonopropionate, 6-(meth)acryloyloxyhexyl phosphonoacetate, 10-(meth)acryloyloxydecyl phosphonoacetate, and acid chlorides, alkali metal salts, and ammonium salts thereof.

[0092] Examples of the monomer having a carboxylic acid group include a monofunctional (meth)acrylic acid ester having one carboxyl group or an acid anhydride group thereof in one molecule, and a monofunctional (meth)acrylic acid ester having multiple carboxyl groups or acid anhydride groups thereof in one molecule.

[0093] Examples of monofunctional monomers having one carboxyl group or an acid anhydride group thereof in one molecule include (meth)acrylic acid, N-(meth)acryloylglycine, N-(meth)acryloylaspartic acid, 2-(meth)acryloyloxyethyl hydrogen succinate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxyethyl hydrogen maleate, O-(meth)acryloyltyrosine, N-(meth)acryloyltyrosine, N-(meth)acryloyloxyethyl hydrogen phthalate, N-(meth)acryloyloxyethyl hydrogen maleate ... Examples of such compounds include acryloylphenylalanine, N-(meth)acryloyl-p-aminobenzoic acid, N-(meth)acryloyl-o-aminobenzoic acid, 2-(meth)acryloyloxybenzoic acid, 3-(meth)acryloyloxybenzoic acid, 4-(meth)acryloyloxybenzoic acid, N-(meth)acryloyl-5-aminosalicylic acid, and N-(meth)acryloyl-4-aminosalicylic acid, as well as compounds in which the carboxyl group of these compounds has been converted to an acid anhydride group.

[0094] Examples of monofunctional monomers having a plurality of carboxyl groups or acid anhydride groups thereof in one molecule include, for example, 6-(meth)acryloyloxyhexane-1,1-dicarboxylic acid, 9-(meth)acryloyloxynonane-1,1-dicarboxylic acid, 10-(meth)acryloyloxydecane-1,1-dicarboxylic acid, 11-(meth)acryloyloxyundecane-1,1-dicarboxylic acid, 12-(meth)acryloyloxydodecane-1,1-dicarboxylic acid, 13-(meth)acryloyloxytridecane-1,1-dicarboxylic acid, 4-(meth)acryloyloxyethyl trimellitate, 4-(meth)acryloyloxyethyl trimellitate anhydride ... Examples of the acryloyloxyethyl ester include oxybutyl trimellitate, 4-(meth)acryloyloxyhexyl trimellitate, 4-(meth)acryloyloxydecyl trimellitate, 2-(meth)acryloyloxyethyl-3'-(meth)acryloyloxy-2'-(3,4-dicarboxybenzoyloxy)propyl succinate, 6-(meth)acryloyloxyethyl naphthalene-1,2,6-tricarboxylic anhydride, 6-(meth)acryloyloxyethyl naphthalene-2,3,6-tricarboxylic anhydride, 4-(meth)acryloyloxyethyl carbonylpropionoyl-1,8-naphthalic anhydride, and 4-(meth)acryloyloxyethyl naphthalene-1,8-tricarboxylic anhydride.

[0095] An example of the monomer having a sulfonic acid group is 2-sulfoethyl (meth)acrylate.

[0096] Furthermore, among the above-mentioned monomers (a-2-3) having an acidic group, from the viewpoint of good adhesive strength when used as a dental polymerizable composition, it is preferable to contain a monomer having a phosphoric acid group or a monomer having a carboxylic acid group, and examples of such monomers include 2-(meth)acryloyloxyethyl dihydrogen phosphate, 3-(meth)acryloyloxypropyl dihydrogen phosphate, 4-(meth)acryloyloxybutyl dihydrogen phosphate, 5-(meth)acryloyloxypentyl dihydrogen phosphate, 6-(meth)acryloyloxyhexyl dihydrogen phosphate, 7-(meth)acryloyloxyheptyl dihydrogen phosphate, 8-(meth)acryloyloxyethyl dihydrogen phosphate, 9-(meth)acryloyloxypropyl dihydrogen phosphate, 10-(meth)acryloyloxybutyl dihydrogen phosphate, 11-(meth)acryloyloxybutyl dihydrogen phosphate, 12-(meth)acryloyloxybutyl dihydrogen phosphate, 13-(meth)acryloyloxypentyl dihydrogen phosphate, 14-(meth)acryloyloxyhexyl dihydrogen phosphate, 15-(meth)acryloyloxyhexyl dihydrogen phosphate, 16-(meth)acryloyloxyhexyl dihydrogen phosphate, 17-(meth)acryloyloxyheptyl dihydrogen phosphate, 18-(meth)acryloyloxyhexyl dihydrogen phosphate, 19-(meth)acryloyloxyhexyl dihydrogen phosphate, 20-(meth)acryloyloxyethyl dihydrogen phosphate, 21-(meth)acryloyloxypropyl dihydrogen phosphate, 22-(meth)acryloyloxypropyl dihydrogen phosphate, 23-(meth)acryloyloxypropyl dihydrogen phosphate, 24-(meth)acryloyloxybutyl dihydrogen phosphate, 2 Cyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, 20-(meth)acryloyloxyicosyl dihydrogen phosphate, 4-(meth)acryloyloxyethyl trimellitate anhydride, 4-(meth)acryloyloxyethyl trimellitate, 11-(meth)acryloyloxyundecane-1,1-Dicarboxylic acid and a mixture of 2-methacryloyloxyethyl dihydrogen phosphate and bis(2-methacryloyloxyethyl)hydrogen phosphate are more preferred, and 8-(meth)acryloyloxyoctyl dihydrogen phosphate, 9-(meth)acryloyloxynonyl dihydrogen phosphate, 10-(meth)acryloyloxydecyl dihydrogen phosphate, 11-(meth)acryloyloxyundecyl dihydrogen phosphate, 12-(meth)acryloyloxydodecyl dihydrogen phosphate, 16-(meth)acryloyloxyhexadecyl dihydrogen phosphate, and 20-(meth)acryloyloxyicosyl dihydrogen phosphate are even more preferred, with 10-(meth)acryloyloxydecyl dihydrogen phosphate being particularly preferred from the viewpoint of a balance with curability.

[0097] In one embodiment, the content of the monomer (a-2-3) having an acidic group in the dental polymerizable composition is, from the viewpoint of adhesion to tooth structure, preferably 0 to 40 mass%, more preferably 2 to 35 mass%, even more preferably 3 to 30 mass%, and particularly preferably 5 to 25 mass%, based on a total of 100 mass% of the dental polymerizable composition.

[0098] One preferred embodiment is a dental polymerizable composition that is substantially free of bisphenol-based aromatic compounds, because it is safer for living organisms. "Substantially free of bisphenol-based aromatic compounds" means that, out of a total of 100% by mass of the dental polymerizable composition, the content of bisphenol-based aromatic compounds is less than 3% by mass, preferably less than 1% by mass, more preferably less than 0.1% by mass, even more preferably less than 0.01% by mass, and particularly preferably 0% by mass.

[0099] <Polymerization initiator (B)> The dental polymerizable composition contains a polymerization initiator (B) for hardening the monomer. As the polymerization initiator (B), a photopolymerization initiator (B-1) or a chemical polymerization initiator (B-2) can be used. These may be used alone or in combination of two or more.

[0100] Examples of the photopolymerization initiator (B-1) include (bis)acylphosphine oxides, thioxanthones, ketals, α-diketones, coumarins, anthraquinones, benzoin alkyl ether compounds, and α-aminoketone compounds.

[0101] Among the (bis)acylphosphine oxides, examples of the acylphosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylphosphine oxide, 2,6-dimethoxybenzoyldiphenylphosphine oxide, 2,6-dichlorobenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylmethoxyphenylphosphine oxide, 2,4,6-trimethylbenzoylethoxyphenylphosphine oxide, 2,3,5,6-tetramethylbenzoyldiphenylphosphine oxide, benzoyldi(2,6-dimethylphenyl)phosphonate, and salts thereof. Examples of bisacylphosphine oxides include bis(2,6-dichlorobenzoyl)phenylphosphine oxide, bis(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,5-dimethylphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,5,6-trimethylbenzoyl)-2,4,4-trimethylpentylphosphine oxide, and sodium bis(2,4,6-trimethylbenzoyl)phosphinate.

[0102] Examples of the thioxanthones include thioxanthone, 2-chlorothioxanthen-9-one, and the like.

[0103] Examples of the ketals include benzyl dimethyl ketal and benzyl diethyl ketal.

[0104] Examples of the α-diketones include diacetyl, benzil, dl-camphorquinone, 2,3-pentadione, 2,3-octadione, 9,10-phenanthrenequinone, 4,4′-oxybenzil, acenaphthenequinone, etc. Among these, dl-camphorquinone is particularly preferred from the viewpoint of having a maximum absorption wavelength in the visible light region.

[0105] Examples of the coumarins include 3,3'-carbonylbis(7-diethylaminocoumarin), 3-(4-methoxybenzoyl)coumarin, 3-thienoylcoumarin, 3-benzoyl-5,7-dimethoxycoumarin, 3-benzoyl-7-methoxycoumarin, 3-benzoyl-6-methoxycoumarin, 3-benzoyl-8-methoxycoumarin, 3-benzoylcoumarin, 7-methoxy-3-(p-nitrobenzoyl)coumarin, 3-(p-nitrobenzoyl)coumarin, 3,5-carbonylbis(7-methoxycoumarin), 3-benzoyl-6-bromo Coumarin, 3,3'-carbonylbiscoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3-benzoylbenzo[f]coumarin, 3-carboxycoumarin, 3-carboxy-7-methoxycoumarin, 3-ethoxycarbonyl-6-methoxycoumarin, 3-ethoxycarbonyl-8-methoxycoumarin, 3-acetylbenzo[f]coumarin, 3-benzoyl-6-nitrocoumarin, 3-benzoyl-7-diethylaminocoumarin, 7-dimethylamino-3-(4-methoxybenzoyl)coumarin, 7-diethylamino-3-(4-methoxybenzoyl)coumarin )coumarin, 7-diethylamino-3-(4-diethylamino)coumarin, 7-methoxy-3-(4-methoxybenzoyl)coumarin, 3-(4-nitrobenzoyl)benzo[f]coumarin, 3-(4-ethoxycinnamoyl)-7-methoxycoumarin, 3-(4-dimethylaminocinnamoyl)coumarin, 3-(4-diphenylaminocinnamoyl)coumarin, 3-[(3-dimethylbenzothiazol-2-ylidene)acetyl]coumarin, 3-[(1-methylnaphtho[1,2-d]thiazol-2-ylidene)acetyl]coumarin, 3,3'-carbo nylbis(6-methoxycoumarin), 3,3'-carbonylbis(7-acetoxycoumarin), 3,3'-carbonylbis(7-dimethylaminocoumarin), 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dibutylamino)coumarin, 3-(2-benzimidazolyl)-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(dioctylamino)coumarin, 3-acetyl-7-(dimethylamino)coumarin, 3,3'-carbonylbis(7-dibutylamino)coumarin, 3,Examples of the compounds include those described in JP-A-9-3109 and JP-A-10-245525, such as 3'-carbonyl-7-diethylaminocoumarin-7'-bis(butoxyethyl)aminocoumarin, 10-[3-[4-(dimethylamino)phenyl]-1-oxo-2-propenyl]-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one, and 10-(2-benzothiazolyl)-2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H,5H,11H-[1]benzopyrano[6,7,8-ij]quinolizin-11-one.

[0106] Among the above-mentioned coumarins, 3,3'-carbonylbis(7-diethylaminocoumarin) and 3,3'-carbonylbis(7-dibutylaminocoumarin) are particularly preferred.

[0107] Examples of the anthraquinones include anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1-bromoanthraquinone, 1,2-benzanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-hydroxyanthraquinone.

[0108] Examples of the benzoin alkyl ether compound include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

[0109] Examples of the α-aminoketone compounds include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one.

[0110] Among these photopolymerization initiators (B-1), it is preferable to use at least one selected from the group consisting of (bis)acylphosphine oxides, α-diketones, and coumarins, which provides a dental polymerizable composition that is excellent in photocurability in the visible and near-ultraviolet regions and exhibits sufficient photocurability using any of the light sources, such as a halogen lamp, a light-emitting diode (LED), and a xenon lamp.

[0111] The content of the photopolymerization initiator (B-1) is not particularly limited, but from the viewpoint of the curability of the obtained dental polymerizable composition, the content is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[0112] Chemical polymerization initiator (B-2) In one embodiment, the dental polymerizable composition can further contain a chemical polymerization initiator (B-2) in order to enable chemical polymerization and improve sealing properties for cavities where light does not reach. As the chemical polymerization initiator (B-2), an organic peroxide is preferably used. The organic peroxide used in the above-mentioned chemical polymerization initiator (B-2) is not particularly limited, and known organic peroxides can be used. Representative organic peroxides include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, peroxyesters, and peroxydicarbonates. Specific examples of these organic peroxides include those described in International Publication No. 2008 / 087977. The chemical polymerization initiator (B-2) may be used alone or in combination of two or more.

[0113] The content of the chemical polymerization initiator (B-2) is not particularly limited, but from the viewpoint of the curability of the obtained dental polymerizable composition, the content is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the radical polymerizable monomer (A) contained in the dental polymerizable composition.

[0114] The content of the polymerization initiator (B) is not particularly limited, but from the viewpoint of the curability of the obtained dental polymerizable composition, the content is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 7 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[0115] <Polymerization accelerator (C)> From the viewpoint of the mechanical strength of the cured product, it is preferable that the dental polymerizable composition further contains a polymerization accelerator (C) in addition to the polymerization initiator (B) (the photopolymerization initiator (B-1) and / or the chemical polymerization initiator (B-2)).

[0116] Examples of the polymerization accelerator (C) used in the present invention include amines, sulfinic acid and its salts, borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds.

[0117] The amines used as the polymerization accelerator (C) are divided into aliphatic amines and aromatic amines. Examples of the aliphatic amine include primary aliphatic amines such as n-butylamine, n-hexylamine, and n-octylamine; secondary aliphatic amines such as diisopropylamine, dibutylamine, and N-methylethanolamine; and tertiary aliphatic amines such as N-methyldiethanolamine, N-ethyldiethanolamine, Nn-butyldiethanolamine, N-lauryldiethanolamine, 2-(dimethylamino)ethyl methacrylate, N-methyldiethanolamine dimethacrylate, N-ethyldiethanolamine dimethacrylate, triethanolamine monomethacrylate, triethanolamine dimethacrylate, triethanolamine trimethacrylate, triethanolamine, trimethylamine, triethylamine, and tributylamine. Among these, from the viewpoint of the curability and storage stability of the dental polymerizable composition, tertiary aliphatic amines are preferred, and among them, N-methyldiethanolamine and triethanolamine are more preferably used.

[0118] Examples of aromatic amines include N,N-bis(2-hydroxyethyl)-3,5-dimethylaniline, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N-bis(2-hydroxyethyl)-3,4-dimethylaniline, N,N-bis(2-hydroxyethyl)-4-ethylaniline, N,N-bis(2-hydroxyethyl)-4-isopropylaniline, N,N-bis(2-hydroxyethyl)-4-t-butylaniline, N,N-bis(2-hydroxyethyl)-3,5-diisopropylaniline, N,N-bis(2-hydroxyethyl)-3,5-di-t-butylaniline, N,N-dimethylaniline, N,N-dimethyl-p-toluidine, N,N-dimethyl-m-toluidine, and N,N-diethyl-p -toluidine, N,N-dimethyl-3,5-dimethylaniline, N,N-dimethyl-3,4-dimethylaniline, N,N-dimethyl-4-ethylaniline, N,N-dimethyl-4-isopropylaniline, N,N-dimethyl-4-t-butylaniline, N,N-dimethyl-3,5-di-t-butylaniline, 4-(N,N-dimethylamino)ethyl benzoate, 4-(N,N-dimethylamino)methyl benzoate, 4-(N,N-dimethylamino)propyl benzoate, 4-(N,N-dimethylamino)n-butoxyethyl benzoate, 4-(N,N-dimethylamino)2-(methacryloyloxy)ethyl benzoate, 4-(N,N-dimethylamino)benzophenone, and 4-(N,N-dimethylamino)butyl benzoate. Among these, from the viewpoint of imparting excellent hardening properties to the dental polymerizable composition, at least one selected from the group consisting of N,N-bis(2-hydroxyethyl)-p-toluidine, ethyl 4-(N,N-dimethylamino)benzoate, n-butoxyethyl 4-(N,N-dimethylamino)benzoate, and 4-(N,N-dimethylamino)benzophenone is preferably used.

[0119] Specific examples of sulfinic acid and its salts, borate compounds, barbituric acid derivatives, triazine compounds, copper compounds, tin compounds, vanadium compounds, halogen compounds, aldehydes, thiol compounds, sulfites, hydrogen sulfites, and thiourea compounds include those described in WO 2008 / 087977.

[0120] The polymerization accelerator (C) may be contained alone or in combination of two or more kinds. The content of the polymerization accelerator (C) used in the present invention is not particularly limited, but from the viewpoint of the curability of the obtained dental polymerizable composition, it is preferably 0.001 to 10 parts by mass, more preferably 0.01 to 8 parts by mass, and even more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the total radical polymerizable monomer (A) contained in the dental polymerizable composition. When the content of the polymerization accelerator (C) is equal to or more than the lower limit, polymerization proceeds sufficiently and sufficient adhesive strength is easily obtained. On the other hand, when the content of the polymerization accelerator (C) is equal to or less than the upper limit, sufficient adhesiveness is easily obtained, and further, precipitation of the polymerization accelerator (C) itself from the dental polymerizable composition can be suppressed.

[0121] <Filler (D)> The dental polymerizable composition preferably further contains a filler (D) in order to increase the mechanical strength (bending strength, etc.) of the cured product. Examples of the filler (D) include inorganic fillers, organic-inorganic composite fillers, and organic fillers. The filler (D) may be used alone or in combination of two or more kinds.

[0122] As the material for the inorganic filler, it is preferable to use various glasses (containing silica as the main component (containing 5% or more by mass of silica, preferably 10% or more by mass of silica), and, as necessary, oxides of heavy metals, boron, aluminum, etc.). Examples of inorganic fillers include glass powders of general compositions such as fused silica, quartz, soda lime silica glass, E glass, C glass, and borosilicate glass (Pyrex (registered trademark) glass); barium glass, strontium borosilicate glass, lanthanum glass ceramics, fluoroaluminosilicate glass, various ceramics, alumina, silica-titania, silica-zirconia, ytterbium oxide, silica-coated ytterbium fluoride, aluminosilicate glass, barium boroaluminosilicate glass, calcium fluoroaluminosilicate glass, and the like. Examples of the inorganic fillers include composite oxides such as luminosilicate glass, strontium fluoroaluminosilicate glass, barium fluoroaluminosilicate glass, and strontium calcium fluoroaluminosilicate glass, diatomaceous earth, kaolin, clay minerals (such as montmorillonite), activated clay, synthetic zeolite, mica, calcium fluoride, ytterbium fluoride, yttrium fluoride, calcium phosphate, barium sulfate, zirconium oxide, titanium oxide, and hydroxyapatite. These may be used alone or in combination of two or more. Among these, inorganic fillers containing metal elements such as aluminum, strontium, zirconium, barium, lanthanum, ytterbium, titanium and bismuth as constituent elements having high X-ray contrast properties (for example, barium glass, alumina, silica-titania, silica-zirconia, silica-coated ytterbium fluoride) are preferred. The inorganic fillers can be used as inorganic fillers having a relatively high refractive index. These can also be used alone or in combination of two or more. Among these, quartz, silica, silica-titania, silica-zirconia, barium glass, ytterbium oxide, and silica-coated ytterbium fluoride are preferred, and quartz, silica, silica-titania, silica-zirconia, barium glass, and silica-coated ytterbium fluoride are more preferred, in that the resulting cured product of the dental polymerizable composition will have excellent mechanical strength and transparency. From the viewpoint of X-ray opacity of the dental polymerizable composition, silica-zirconia, barium glass, and silica-coated ytterbium fluoride are preferred, and from the viewpoint of storage stability, silica-coated ytterbium fluoride is particularly preferred.

[0123] From the viewpoint of the handling property and mechanical strength of the obtained dental polymerizable composition, the average particle size of the inorganic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 20 μm, and further preferably 0.005 to 10 μm. 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. A preferred embodiment includes a dental polymerizable composition in which the filler (D) is an inorganic filler.

[0124] The inorganic filler may be a commercially available product. Examples of commercially available products include silica such as Aerosil (registered trademark) 90, Aerosil (registered trademark) 130, Aerosil (registered trademark) 150, Aerosil (registered trademark) 200, Aerosil (registered trademark) 255, Aerosil (registered trademark) 300, Aerosil (registered trademark) 380, Aerosil (registered trademark) OX50, and Aerosil (registered trademark) R972 (all manufactured by Nippon Aerosil Co., Ltd.), barium glass such as GM27884 and 8235 (all manufactured by SCHOTT), product code "E-3000" (manufactured by Estech), strontium borosilicate glass (E-4000, manufactured by ESSTECH), lanthanum glass ceramics (GM31684, manufactured by Schott), and fluoroaluminosilicate glass (GM35429, G018-091, G018-117, manufactured by Schott).

[0125] The inorganic filler may be amorphous, crystalline, or a mixture of both, but preferably contains at least an amorphous portion.

[0126] The shape of the inorganic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used, for example, irregular filler (crushed filler) and spherical filler. From the viewpoint of improving the mechanical strength of the cured product of the dental polymerizable composition, it is preferable to use an irregular filler as the inorganic filler, and from the viewpoint of handling, it is preferable to use a spherical filler. A spherical filler is a filler in which the particles observed within a unit field of view of a photograph of the filler taken with an electron microscope are rounded, and the average uniformity obtained by dividing the particle diameter in the direction perpendicular to the maximum diameter by the maximum diameter is 0.6 or more.

[0127] In order to adjust the mechanical strength and fluidity of the cured product of the dental polymerizable composition, the inorganic filler is preferably surface-treated in advance with a known surface treatment agent such as a silane coupling agent. For example, the hydroxyl groups present on the surface of the inorganic filler can be surface-treated with the surface treatment agent to obtain an inorganic filler with the hydroxyl groups surface-treated.

[0128] Examples of the surface treatment agent include silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloyloxypropyltrimethoxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltriethoxysilane. Of these, vinyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, 8-methacryloyloxyoctyltrimethoxysilane, 11-methacryloyloxyundecyltrimethoxysilane, and γ-aminopropyltriethoxysilane are preferred.

[0129] The surface treatment method can be any known method without any particular limitation, for example, a method of spraying the above-mentioned surface treatment agent while vigorously stirring the inorganic filler, a method of dispersing or dissolving the inorganic filler and the above-mentioned surface treatment agent in a suitable solvent and then removing the solvent, or a method of hydrolyzing the alkoxy group of the above-mentioned surface treatment agent in an aqueous solution with an acid catalyst to convert it to a silanol group, attaching it to the inorganic filler surface in the aqueous solution, and then removing the water, etc. In any of these methods, the reaction between the inorganic filler surface and the above-mentioned surface treatment agent can be completed by heating in the range of 50 to 150 ° C., and the surface treatment can be performed. The amount of surface treatment is not particularly limited, and for example, 0.1 to 40 parts by mass of the surface treatment agent can be used for 100 parts by mass of the inorganic filler before treatment.

[0130] The organic-inorganic composite filler is obtained by adding a monomer to the inorganic filler described above in advance, forming a paste, polymerizing, and pulverizing the mixture. The organic-inorganic composite filler refers to a filler containing an inorganic filler and a polymer of a monomer. For example, the organic-inorganic composite filler may be a mixture of Bis-GMA, 3G, and a surface-treated silica filler, polymerized, and then pulverized. The shape of the organic-inorganic composite filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. The organic-inorganic composite filler may also be used alone or in combination of two or more types, and it is preferable that the organic-inorganic composite filler is also surface-treated from the viewpoint of mechanical strength. Examples and preferred types of surface treatment agents are the same as those of the inorganic filler. From the viewpoint of the handleability and mechanical strength of the resulting dental polymerizable composition, the average particle size of the organic-inorganic composite filler is preferably 0.001 to 50 μm, more preferably 0.001 to 20 μm, and even more preferably 0.005 to 15 μm.

[0131] Examples of the organic filler material include polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, crosslinked polymethyl methacrylate, crosslinked polyethyl methacrylate, polyamide, polyvinyl chloride, polystyrene, chloroprene rubber, nitrile rubber, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer, etc., which may be used alone or as a mixture of two or more. The shape of the organic filler is not particularly limited, and the particle size of the filler can be appropriately selected and used. From the viewpoint of the handleability and mechanical strength of the obtained dental polymerizable composition, the average particle size of the organic filler is preferably 0.001 to 50 μm, more preferably 0.001 to 20 μm, and even more preferably 0.005 to 15 μm.

[0132] In this specification, the average particle size of the filler can be determined by a laser diffraction scattering method or by observing the particles with an electron microscope. Specifically, the laser diffraction scattering method is convenient for measuring particle sizes of 0.1 μm or more, while electron microscope observation is convenient for measuring the particle size of ultrafine particles less than 0.1 μm. 0.1 μm is the measurement value obtained by the laser diffraction scattering method. In the case of particles formed by agglomeration of primary particles such as aggregated particles, there are an average particle size of the primary particles and an average particle size of the secondary particles, but the average particle size of the filler is the average particle size of the secondary particles with a larger particle size.

[0133] Specifically, the laser diffraction scattering method can be performed by, for example, using a laser diffraction particle size distribution analyzer (SALD-2300, manufactured by Shimadzu Corporation) and measuring on a volume basis using a 0.2% aqueous solution of sodium hexametaphosphate as a dispersion medium.

[0134] Specifically, electron microscope observation can be performed by taking a photograph of the particles with an electron microscope (S-4000 model, manufactured by Hitachi, Ltd.) and measuring the particle diameters of the particles (200 or more) observed within a unit field of view of the photograph using image analysis type particle size distribution measurement software (Mac-View (manufactured by Mountec Co., Ltd.)). At this time, the particle diameter is determined as the arithmetic mean value of the longest and shortest lengths of the particles, and the average particle diameter is calculated from the number of particles and their particle diameters.

[0135] The content of the filler (D) is not particularly limited, but from the viewpoints of handleability and mechanical strength of the cured product, it is preferably 0 to 90 mass %, more preferably 55 to 85 mass %, and even more preferably 60 to 80 mass %, per 100 parts by mass of the dental polymerizable composition.

[0136] <Fluoride ion releasing substances> In some embodiments, the dental polymerizable composition may further contain a fluoride ion releasing substance. By containing a fluoride ion releasing substance, a dental polymerizable 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; and metal fluorides such as sodium fluoride, potassium fluoride, sodium monofluorophosphate, lithium fluoride, and ytterbium fluoride. The above fluoride ion releasing substances may be contained alone or in combination of two or more kinds.

[0137] In addition, the dental polymerizable composition may contain known additives within the range that does not deteriorate the performance. Such additives include polymerization inhibitors, antioxidants, colorants (pigments, dyes), ultraviolet absorbers, fluorescent agents, solvents such as organic solvents, thickeners, etc. The additives may be used alone or in combination of two or more. In one embodiment, the content of the solvent (e.g., water, organic solvent) in the dental polymerizable composition is preferably less than 1 mass %, more preferably less than 0.1 mass %, and even more preferably less than 0.01 mass %, based on the total mass of the dental polymerizable composition.

[0138] In another embodiment, it is preferable to contain a solvent. Examples of the solvent include water, an organic solvent, and a mixture thereof.

[0139] The water used must be substantially free of impurities that adversely affect adhesion, and distilled water or ion-exchanged water is preferred. If the water content is too low, the demineralization promotion effect may not be sufficiently obtained, and if the water content is too high, adhesion may decrease. Therefore, the water content is preferably in the range of 1 to 50 mass %, more preferably in the range of 5 to 30 mass %, and even more preferably in the range of 10 to 20 mass %, based on 100 mass % of the total dental polymerizable composition.

[0140] When the dental polymerizable composition of the present invention contains an organic solvent, the adhesiveness, coatability, and permeability into tooth structure can be further improved, and separation of the components of the composition can be further prevented. As the organic solvent, an organic solvent that has a boiling point of 150°C or lower under normal pressure and a solubility in water at 25°C of 5% by mass or more, more preferably 30% by mass or more, and even more preferably is soluble in water in any proportion, is usually used.

[0141] Examples of the organic solvent include alcohol solvents such as methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, and 2-methyl-2-propanol; ketone solvents such as acetone and methyl ethyl ketone; ether solvents such as tetrahydrofuran, diethyl ether, and diisopropyl ether; hydrocarbon solvents such as hexane and toluene; halogenated hydrocarbon solvents such as chloroform; and ester solvents such as ethyl acetate and butyl acetate. Among these, when considering both safety to the living body and ease of removal based on volatility, it is preferable that the organic solvent is a water-soluble organic solvent. Specifically, ethanol, 2-propanol, 2-methyl-2-propanol, acetone, and tetrahydrofuran are preferred, and ethanol, 2-propanol, 2-methyl-2-propanol, and tetrahydrofuran are more preferred. The content of the organic solvent is not particularly limited, and in some embodiments, the incorporation of the organic solvent is not required. In the embodiment in which the organic solvent is used, the content of the organic solvent is preferably in the range of 1 to 70 mass %, more preferably in the range of 5 to 50 mass %, and even more preferably in the range of 10 to 30 mass %, relative to 100 mass % of the total dental polymerizable composition.

[0142] The dental polymerizable composition of the present invention preferably contains a polymerization inhibitor from the viewpoint of storage stability and adjustment of hardening property. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, dibutyl hydroquinone, dibutyl hydroquinone monomethyl ether, t-butyl catechol, 2-t-butyl-4,6-dimethylphenol, 2,6-di-t-butylphenol, 3,5-di-t-butyl-4-hydroxytoluene, etc. These may be used alone or in combination of two or more. The content of the polymerization inhibitor is preferably 0.001 to 1.0 part by mass relative to 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[0143] The dental polymerizable composition of the present invention preferably contains an ultraviolet absorber from the viewpoint of photostability against environmental light such as fluorescent lamps and LEDs, and from the viewpoint of suppressing discoloration of the cured product. Examples of ultraviolet absorbents include benzotriazole compounds such as 2-(2-hydroxyphenyl)benzotriazole, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-ethylphenyl)benzotriazole, 2-(2-hydroxy-5-propylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, and 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chloro-2H-benzotriazole (Tinuvin 326), and benzimidazole compounds, with Tinuvin 326 being preferred. These may be used alone or in combination of two or more.

[0144] The dental polymerizable composition of the present invention preferably contains a fluorescent agent from the viewpoint of aesthetics in order to reproduce a color tone close to that of tooth tissue. As the fluorescent agent, any known fluorescent agent can be used without any restrictions, but a phthalate ester-based fluorescent agent is preferred.

[0145] Specific examples of phthalate ester fluorescent agents include dimethyl 2,5-dihydroxyterephthalate, diethyl 2,5-dihydroxyterephthalate, dimethylaminoterephthalate, diethylaminoterephthalate, etc., and more preferred are phthalate ester fluorescent agents substituted with a hydroxyl group such as diethyl 2,5-dihydroxyterephthalate. The fluorescent agents may be used alone or in combination of two or more.

[0146] The content of the fluorescent agent is not particularly limited, but a certain amount is necessary to ensure fluorescence, and conversely, if the content is too high, it tends to be difficult to ensure light stability. In order to achieve a good balance between light stability and fluorescence, the content is preferably 0.005 to 0.5 parts by mass, more preferably 0.01 to 0.1 parts by mass, relative to 100 parts by mass of the total of the radical polymerizable monomers (A) contained in the dental polymerizable composition.

[0147] The dental polymerizable composition of the present invention preferably contains a colorant to reproduce a color tone close to that of tooth structure. The type of the colorant is not particularly limited, and any of inorganic pigments and / or organic pigments can be used without limitation depending on the color tone of the dental polymerizable composition to be targeted. The colorant may be used alone or in combination of two or more kinds.

[0148] The coloring agent is a component that is added in a small amount to the dental polymerizable composition. The content of one type of coloring agent is less than 1.0 mass% in the total 100 mass% of the dental polymerizable composition.

[0149] The shape of the colorant is not particularly limited, and any particle shape such as spherical, needle-like, plate-like, crushed, or scaly may be used without any restrictions.

[0150] Examples of inorganic pigments include chromates such as yellow lead, zinc yellow, and barium yellow; ferrocyanides such as iron blue; sulfides such as vermilion, cadmium yellow, zinc sulfide, and cadmium red; sulfates such as barium sulfate, zinc sulfate, and strontium sulfate; oxides such as zinc white, antimony white, titanium white, red iron oxide, iron black, and chromium oxide; hydroxides such as aluminum hydroxide; silicates such as calcium silicate and ultramarine; and carbons such as carbon black and graphite.

[0151] Examples of organic pigments include nitroso pigments such as naphthol green B and naphthol green Y; nitro pigments such as naphthol yellow S and xylene fast yellow 2G; insoluble azo pigments such as toluidine red 4R, brilliant fast scarlet, hansa yellow, and pigment yellow; poorly soluble azo pigments such as lithol red, lake red C, and lake red D; soluble azo pigments such as brilliant carmine 6B, toluidine red F5R, pigment scarlet 3B, and bordeaux 10B; phthalocyanine pigments such as phthalocyanine blue, phthalocyanine green, and sky blue; basic dye pigments such as rhodamine lake, malachite green lake, and methyl violet lake; and acidic dye pigments such as peacock blue lake, eosine lake, quinoline yellow lake, and aluminum lake.

[0152] Among these colorants, inorganic pigments such as titanium white, red iron oxide, iron oxide yellow, and the like, which are superior in heat resistance and light resistance to organic pigments, are more preferable.

[0153] The content of the colorant in the dental polymerizable composition of the present invention is not limited as long as it is within the range in which the effects of the present invention can be obtained, but from the viewpoint of aesthetics, it is preferably 0.0005 parts by mass or more, more preferably 0.002 parts by mass or more, even more preferably 0.004 parts by mass or more, and particularly preferably 0.006 parts by mass or more, relative to a total of 100 parts by mass of the radical polymerizable monomer (A) contained in the dental polymerizable composition. By being equal to or more than the lower limit, it is possible to effectively prevent the filling part formed by filling the dental polymerizable composition into the cavity from having a dark and sunken impression. The content of the colorant is preferably 2.0 parts by mass or less, more preferably 1.0 parts by mass or less, even more preferably 0.5 parts by mass or less, and particularly preferably 0.3 parts by mass or less, based on 100 parts by mass of the total radical polymerizable monomer (A) contained in the dental polymerizable composition. By being equal to or less than the upper limit, the color tone of the natural tooth at the cavity bottom can be effectively reflected in the filling part. The content of the colorant is preferably 0.00001% by mass or more, more preferably 0.0001% by mass or more, even more preferably 0.0005% by mass or more, and particularly preferably 0.001% by mass or more, based on the total 100% by mass of the dental polymerizable composition. The content of the colorant is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, even more preferably 0.1% by mass or less, and particularly preferably 0.07% by mass or less.

[0154] The dental polymerizable composition of the present invention can achieve both excellent mechanical strength and reduced polymerization shrinkage stress during hardening, and can be suitably used for dental treatment applications such as dental composite resins (particularly preferably self-adhesive composite resins), dental adhesives, and dental cements.

[0155] An example of a composition ratio suitable for a dental composite resin is shown below. The content of each component in the dental composite resin is preferably 0.1 to 10 mass% of the radical polymerizable monomer (a-1), 5 to 98 mass% of the hydrophobic monomer (a-2-1) having no acidic group, 0 to 98 mass% of the hydrophilic monomer (a-2-2) having no acidic group, and 0 to 90 mass% of the filler (D) in the total 100 mass% of the dental polymerizable composition. It is more preferable that the composition contains 10 to 50 mass% of monomer (a-2-1), 0 to 50 mass% of hydrophilic monomer (a-2-2) having no acidic group, and 55 to 85 mass% of filler (D), and it is even more preferable that the composition contains 2 to 5 mass% of radical polymerizable monomer (a-1), 10 to 30 mass% of hydrophobic monomer (a-2-1) having no acidic group, 0 to 30 mass% of hydrophilic monomer (a-2-2) having no acidic group, and 60 to 80 mass% of filler (D). In addition, the photopolymerization initiator (B-1) is preferably 0.001 to 10 parts by mass, and the polymerization accelerator (C) is preferably 0.001 to 10 parts by mass, the photopolymerization initiator (B-1) is preferably 0.01 to 7 parts by mass, and the polymerization accelerator (C) is preferably 0.01 to 8 parts by mass, and the photopolymerization initiator (B-1) is preferably 0.1 to 5 parts by mass, and the polymerization accelerator (C) is preferably 0.1 to 5 parts by mass, relative to a total of 100 parts by mass of the radical polymerizable monomer (A) contained in the dental polymerizable composition. The dental polymerizable composition used as a dental composite resin does not need to contain the hydrophilic monomer (a-2-2).

[0156] An example of a suitable composition ratio for a dental self-adhesive dental composite resin is shown below. In a total of 100% by mass of the dental polymerizable composition, it is preferable that the composition contains 0.1 to 10% by mass of a radical polymerizable monomer (a-1), 5 to 98% by mass of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 98% by mass of a hydrophilic monomer (a-2-2) having no acidic group, 0 to 40% by mass of a monomer (a-2-3) having an acidic group, and 0 to 90% by mass of a filler (D). It is more preferable that the monomer (a-2-1) contains 0 to 50 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 2 to 35 mass% of a monomer (a-2-3) having an acidic group, and 55 to 85 mass% of a filler (D), and it is further preferable that the monomer (a-2-1) contains 2 to 5 mass% of a radically polymerizable monomer (a-1), 10 to 30 mass% of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 30 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 5 to 25 mass% of a monomer (a-2-3) having an acidic group, and 60 to 80 mass% of a filler (D). Furthermore, relative to a total of 100 parts by mass of the radically polymerizable monomer (A) contained in the dental polymerizable composition, the amount of the photopolymerization initiator (B-1) is preferably 0.001 to 10 parts by mass and the amount of the polymerization accelerator (C) is preferably 0.001 to 10 parts by mass, the amount of the photopolymerization initiator (B-1) is more preferably 0.01 to 7 parts by mass and the amount of the polymerization accelerator (C) is 0.01 to 8 parts by mass, and the amount of the photopolymerization initiator (B-1) is even more preferably 0.1 to 5 parts by mass and the amount of the polymerization accelerator (C) is even more preferably 0.1 to 5 parts by mass. The dental polymerizable composition used as a self-adhesive dental composite resin may not contain the hydrophilic monomer (a-2-2).

[0157] An example of a composition ratio suitable for a dental adhesive is shown below. In a total of 100% by mass of the dental polymerizable composition, it is preferable that the composition contains 0.1 to 10% by mass of a radical polymerizable monomer (a-1), 5 to 98% by mass of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 98% by mass of a hydrophilic monomer (a-2-2) having no acidic group, 1 to 40% by mass of a monomer (a-2-3) having an acidic group, and 0 to 90% by mass of a filler (D). It is more preferable that the copolymer contains 0 to 50 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 2 to 35 mass% of a monomer (a-2-3) having an acidic group, and 0 to 85 mass% of a filler (D), and it is further preferable that the copolymer contains 2 to 5 mass% of a radically polymerizable monomer (a-1), 10 to 30 mass% of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 30 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 5 to 25 mass% of a monomer (a-2-3) having an acidic group, and 1 to 50 mass% of a filler (D). Furthermore, relative to a total of 100 parts by mass of the radically polymerizable monomer (A) contained in the dental polymerizable composition, the amount of the photopolymerization initiator (B-1) is preferably 0.001 to 10 parts by mass and the amount of the polymerization accelerator (C) is preferably 0.001 to 10 parts by mass, the amount of the photopolymerization initiator (B-1) is more preferably 0.01 to 7 parts by mass and the amount of the polymerization accelerator (C) is 0.01 to 8 parts by mass, and the amount of the photopolymerization initiator (B-1) is even more preferably 0.1 to 5 parts by mass and the amount of the polymerization accelerator (C) is even more preferably 0.1 to 5 parts by mass.

[0158] An example of a composition ratio suitable for dental cement is shown below. In a total of 100% by mass of the dental polymerizable composition, it is preferable that the composition contains 0.1 to 10% by mass of a radical polymerizable monomer (a-1), 5 to 98% by mass of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 98% by mass of a hydrophilic monomer (a-2-2) having no acidic group, 0 to 40% by mass of a monomer (a-2-3) having an acidic group, and 0 to 90% by mass of a filler (D). It is more preferable that the monomer (a-2-1) contains 0 to 50 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 2 to 35 mass% of a monomer (a-2-3) having an acidic group, and 55 to 85 mass% of a filler (D), and it is further preferable that the monomer (a-2-1) contains 2 to 5 mass% of a radically polymerizable monomer (a-1), 10 to 30 mass% of a hydrophobic monomer (a-2-1) having no acidic group, 0 to 30 mass% of a hydrophilic monomer (a-2-2) having no acidic group, 5 to 25 mass% of a monomer (a-2-3) having an acidic group, and 60 to 80 mass% of a filler (D). Furthermore, relative to a total of 100 parts by mass of the radically polymerizable monomer (A) contained in the dental polymerizable composition, the amount of the photopolymerization initiator (B-1) is preferably 0.001 to 10 parts by mass and the amount of the polymerization accelerator (C) is preferably 0.001 to 10 parts by mass, the amount of the photopolymerization initiator (B-1) is more preferably 0.01 to 7 parts by mass and the amount of the polymerization accelerator (C) is 0.01 to 8 parts by mass, and the amount of the photopolymerization initiator (B-1) is even more preferably 0.1 to 5 parts by mass and the amount of the polymerization accelerator (C) is even more preferably 0.1 to 5 parts by mass. The dental composition used as a dental cement may not contain the hydrophilic monomer (a-2-2). When used as a dental cement of the type that uses a pretreatment material, the dental composition may not contain the monomer (a-2-3) having an acidic group.

[0159] The dental polymerizable composition can be easily produced by a method known to those skilled in the art by mixing the radical polymerizable monomer (a-1), and optionally the radical polymerizable monomer (a-2), the polymerization initiator (B), and the filler (D), and further mixing other components as necessary. EXAMPLES

[0160] The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to the examples. In the examples, the parts are by weight unless otherwise specified.

[0161] Next, the components of the dental polymerizable compositions of the Examples and Comparative Examples are shown below together with their abbreviations.

[0162] [Radically polymerizable monomer (a-1)] [Production Example 1: Production of radically polymerizable monomer (a-1-1)] In an air atmosphere, 9,9-bis[4-(aminophenoxy)phenyl]fluorene (BPF-AN, manufactured by JFE Chemical Co., Ltd.) 3.0g (5.6mmol), 2-(2-methacryloyloxyethyloxy)ethyl isocyanate ("KarenzMOI-EG" manufactured by Showa Denko K.K.) 2.2mL (11.2mmol), dibutylhydroxytoluene 0.7mg (0.003mmol), dibutyltin dilaurate 7.5μL (0.01mmol), and toluene 70mL were mixed and reacted at 80°C for 8 hours. The solvent was removed for 1 hour at 50°C under reduced pressure in an evaporator in the presence of air, and the obtained crude product was subjected to silica gel column chromatography (hexane / ethyl acetate / methanol = 5 / 3 / 1 → 4 / 4 / 1) to obtain 4.7g of white solid (a-1-1) (yield: 89%, LC purity: 99.1%). 1 H-NMR confirmed that a compound represented by the following chemical formula (a-1-1) was obtained. [ka]

[0163] [Production Example 2: Production of radically polymerizable monomer (a-1-2)] A white solid (a-1-2) was obtained in the same manner as in Production Example 1, except that 2-(2-methacryloyloxyethyloxy)ethyl isocyanate (manufactured by Showa Denko K.K., "Karenz MOI-EG") was used instead of 2-methacryloyloxyethyl isocyanate (manufactured by Showa Denko K.K., "Karenz MOI") (yield: 76.0%, LC purity: 97.7%). 1H-NMR confirmed that a compound represented by the following chemical formula (a-1-2) was obtained. [ka]

[0164] [Production Example 3: Production of radically polymerizable monomer (a-1-3)] Under an air atmosphere, 5.3 g (10 mmol) of 9,9-bis[4-(aminophenoxy)phenyl]fluorene (BPF-AN, manufactured by JFE Chemical Corporation) and 200 mL of tetrahydrofuran were mixed, to which 3.0 g (3 mmol) of triethylamine was added and cooled to 0°C. Then, 2.2 g (24 mmol) of acryloyl chloride was added dropwise over 15 minutes, and the mixture was warmed to room temperature and stirred overnight. After the reaction was completed, water was added, and the mixture was extracted with chloroform, washed with water and saturated saline, dried over sodium sulfate, filtered, and concentrated. The obtained crude product was subjected to silica gel column chromatography (chloroform / methanol=50 / 1) to obtain 5.9 g of a white solid (a-1-3) (yield: 92.1%, LC purity: 98.9%). 1 H-NMR confirmed that a compound represented by the following chemical formula (a-1-3) was obtained. [ka]

[0165] [Radically polymerizable monomer (a-2)] D-2.6E: 2,2-bis(4-methacryloyloxypolyethoxyphenyl)propane (average number of moles of ethoxy groups added: 2.6) BPEF-MA: 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene methacrylate (compound below) [ka] 3G: Triethylene glycol dimethacrylate UDMA: [2,2,4-trimethylhexamethylenebis(2-carbamoyloxyethyl)]dimethacrylate

[0166] [Polymerization initiator (B)] TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide CQ: Camphorquinone

[0167] [Polymerization accelerator (C)] PDE: Ethyl p-dimethylaminobenzoate

[0168] Filler Filler 1: 100 parts by mass of NF180 (barium glass (average primary particle size 0.18 μm, manufactured by Schott)) was dispersed in 300 parts by mass of ethanol, and 2.5 parts by mass of surface treatment agent 11-MUS (11-methacryloyloxyundecyltrimethoxysilane), 0.15 parts by mass of acetic acid, and 5 parts by mass of water were added and stirred at room temperature for 2 hours. The solvent was distilled off under reduced pressure, and the mixture was further surface-treated by drying at 90°C for 3 hours to obtain Filler 1. Filler 2: Spherical silica surface-treated with γ-methacryloyloxypropyltrimethoxysilane (average particle size: 1.5 μm, product name "Silica Microbead P-500", manufactured by JGC Catalysts and Chemicals Co., Ltd.)

[0169] [others] BHT: 3,5-di-t-butyl-4-hydroxytoluene (polymerization inhibitor)

[0170] [Preparation of dental composite resin] The raw materials shown in Table 1 were mixed and kneaded in a dark place at room temperature (23° C.) to make a homogenous mixture, which was then vacuum degassed to prepare a paste-like dental composite resin.

[0171] Test Example 1 Polymerization shrinkage stress A dental ceramic adhesive (product name "Clearfil (registered trademark) Ceramic Primer Plus", manufactured by Kuraray Noritake Dental Co., Ltd.) was applied as a pretreatment material to a 5.0 mm thick glass plate that had been sandblasted with 50 μm alumina powder, and then dried with an air blower. A dental adhesive (product name "Clearfil (registered trademark) Megabond (registered trademark) 2", manufactured by Kuraray Noritake Dental Co., Ltd.) was applied to one side of a stainless steel washer (inner diameter 5.3 mm × thickness 0.8 mm) that had been coated with a release agent prepared separately, so that no excess was left. The surface of the washer on which the dental adhesive had been applied was then closely attached to the glass plate, and the washer and glass plate were fixed by irradiating the surface of the glass plate not in contact with the washer with light using a dental visible light irradiator (Pencure 2000, manufactured by Morita Corporation) in standard mode for 10 seconds. Next, in order to fix the glass plate and the dental composite resin of the Examples and Comparative Examples, about 8 mg of the dental adhesive was applied to the inside of the washer (the surface of the glass plate and the side surface of the inner diameter of the washer) and irradiated with light for 10 seconds in standard mode using a dental visible light irradiator (Pencure 2000, manufactured by Morita Corporation). After that, the dental composite resin paste was filled into the washer. A sandblasted stainless steel jig (φ5 ​​mm) was prepared separately, the dental adhesive was applied, and the side to which the adhesive was applied was irradiated with light in standard mode for 10 seconds using a dental visible light irradiator (Pencure 2000, manufactured by Morita Corporation). After the light irradiation, the dental composite resin paste in the washer was sandwiched between the stainless steel jig and the glass plate, and excess paste was removed.

[0172] The dental composite resin was hardened by irradiating the glass plate side of the paste filled in the washer with light in standard mode for 10 seconds using a dental polymerization LED light irradiator (manufactured by Morita Corporation, product name "Pencure 2000"), and the stress applied 3 minutes after the start of light irradiation was taken as the polymerization shrinkage stress. This was measured (n=3) using a universal testing machine (Autograph AG-I 100kN, manufactured by Shimadzu Corporation) and the average value was calculated.

[0173] The polymerization shrinkage stress is preferably less than 10.0 MPa, more preferably less than 8.0 MPa, and even more preferably less than 6.0 MPa.

[0174] Test Example 2 Compressive strength The dental composite resin was cured using a dental LED light irradiator (manufactured by Morita Corporation, product name "Pencure 2000") and test pieces (4mmφ x 4mm) were prepared. The test pieces were immersed in 70°C water for one week, removed from the water, and measured for compressive strength (n=5) using a universal testing machine (product name: Autograph AG-X 100kN, manufactured by Shimadzu Corporation) at a crosshead speed of 2mm / min, and the average value was calculated.

[0175] The compressive strength of the cured product is preferably 400 MPa or more, more preferably 430 MPa or more, and even more preferably 450 MPa or more.

[0176] [Table 1]

[0177] As can be seen from the results in Table 1, the dental composite resins of the examples had a polymerization shrinkage stress of less than 8.0 MPa and a compressive strength of the cured product of 430 MPa or more.

[0178] On the other hand, in Comparative Example 1, the polymerization shrinkage stress could not be reduced to less than 10.0 MPa. In Comparative Example 2, the compressive strength could not be increased to 400 MPa or more. In Comparative Example 1, it is presumed that the use of only a general bisphenol-based aromatic compound resulted in an insufficient molecular volume occupied by the compound, and therefore the effect of reducing the polymerization shrinkage stress was insufficient. In Comparative Example 2, when the polymerizable monomer is compared with the radical polymerizable monomer (a-1) of the Examples, it is presumed that the polymerizable monomer in Comparative Example 2 does not exhibit sufficient mechanical strength because it has fewer aromatic rings in the side chain. [Industrial Applicability]

[0179] The polymerizable monomer of the present invention can be suitably used in a dental polymerizable composition.

Claims

1. A polymerizable monomer having a skeleton represented by the following general formula (1): 【Chemistry 1】 (wherein * represents a bond, R 1 ~R 6 each independently represents a substituent, R 7 , and R 8 each independently represents a hydrogen atom or an organic group, X 1 , and X 2 are each independently an oxygen atom, a sulfur atom, or NR 9 (R 9 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 each independently represents an aromatic hydrocarbon ring; k and m each independently represent an integer of 0 to 4; n, p, q, and r each independently represent an integer of 0 or 1 or more.

2. The polymerizable monomer according to claim 1, wherein at least one of the two * in general formula (1) is a polymerizable monomer bonded at the * site of a functional group represented by the following general formula (2): 【Chemistry 2】 (In the formula, R 10 represents a hydrogen atom or a methyl group, R 11 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, a carbamoyl group, a (meth)acryloyloxy group, a (meth)acryloylpoly(oxyethylene) group, or a (meth)acryloylpoly(oxyethylene)carbamoyl group; X 3 is an oxygen atom, a sulfur atom, or NR 12 (R 12 represents a hydrogen atom or an alkyl group having 1 to 8 carbon atoms; s represents an integer of 1 to 15, t is 0 or 1, and w is an integer of 0 to 6.

3. Ring Z 1 , ring Z 2 , ring Z 3 , and ring Z 4 The polymerizable monomer according to claim 1 or 2, wherein is a benzene ring or a naphthalene ring.

4. X 1 , and X 2 The polymerizable monomer according to claim 1 or 2, wherein is an oxygen atom.

5. R 1 ~R 6 and each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 30 carbon atoms.

6. X 3 The polymerizable monomer according to claim 2 , wherein is an oxygen atom.

7. containing a radical polymerizable monomer (A) and a polymerization initiator (B), A dental polymerizable composition, wherein the radical polymerizable monomer (A) comprises a radical polymerizable monomer (a-1) which is the polymerizable monomer according to claim 1 or 2.

8. The dental polymerizable composition according to claim 7 , further comprising a polymerization accelerator (C).

9. The dental polymerizable composition according to claim 7 , further comprising a filler (D).

10. 8. The dental polymerizable composition according to claim 7, wherein the content of the radical polymerizable monomer (a-1) is 0.1 to 10 mass % in a total of 100 mass % of the dental polymerizable composition.

11. 8. The dental polymerizable composition according to claim 7, wherein the radical polymerizable monomer (A) further comprises a radical polymerizable monomer (a-2) other than the radical polymerizable monomer (a-1).

12. 12. The dental polymerizable composition according to claim 11, wherein the content of the radical polymerizable monomer (a-2) is 10 to 30 mass% in a total of 100 mass% of the dental polymerizable composition.

13. 8. The dental polymerizable composition according to claim 7, wherein a content of the polymerization initiator (B) is 0.001 to 10 parts by mass relative to 100 parts by mass of the total of the radical-polymerizable monomers (A) contained in the dental polymerizable composition.

14. 8. The dental polymerizable composition according to claim 7, wherein a content of the polymerization accelerator (C) is 0.001 to 10 parts by mass per 100 parts by mass of the total of the radical-polymerizable monomers (A) contained in the dental polymerizable composition.

15. A dental composite resin comprising the dental polymerizable composition according to claim 7.

16. A self-adhesive composite resin comprising the dental polymerizable composition according to claim 7.

17. A dental adhesive comprising the dental polymerizable composition according to claim 7.

18. A dental cement comprising the dental polymerizable composition according to claim 7.

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