JP2005187385A - Cation-curable composition for dental use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a cation-curable composition suitably usable as a filling restorative material for dental use, short in both curing time and gelatinizing time, polymerizable and curable in a short time, therefore imposing no heavy burden on relevant patients even if used in the oral cavity. <P>SOLUTION: This cation-curable composition for dental use comprises two cation-polymerizable compounds, i.e. A mol of an oxetane compound having in one molecule (a) oxetane functional groups and B mol of a bicycloorthoester compound having in one molecule (b) bicycloorthoester functional groups, wherein the compounding proportion of both the compounds is adjusted so that the ratio (a×A)/(b×B) falls within the range (99.99:0.01) to (50:50). Thereby, both the curing time and gelatinizing time of this composition becomes shorter than the case when using the oxetane compound or the bicycloorthoester compound singly. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a cationically curable composition suitably used as a dental material, particularly as a dental filling restorative material.

  In the restoration of a tooth damaged by caries, fracture or the like, a photo-curable filling / restoring material generally called a composite resin is widely used because of its easy operation and high aesthetics. Such a composite resin is usually composed of a polymerizable monomer, a filler and a polymerization initiator, and the polymerizable monomer is a (meth) acrylate radical polymerizable single monomer because of its good photopolymerizability. The body is used.

  However, since radically polymerizable monomers are subject to polymerization inhibition by oxygen, when polymerized and cured in the oral cavity, an unpolymerized layer or a layer with a low degree of polymerization remains on the surface. For this reason, there is a problem that coloring and discoloration with time are difficult to obtain sufficient aesthetics. Therefore, the conventional dental composite resin using a radical polymerizable monomer has to be polished and cured in the oral cavity before the surface is sufficiently polished in order to fully exhibit its good aesthetics. Must not.

  Furthermore, ordinary radically polymerizable monomers are of the addition polymerization type and have a problem that the polymerization shrinkage rate is essentially large due to the curing mechanism.

  When filling and curing a filling restorative material such as a composite resin to the cavity of a tooth that requires restoration, it is necessary to irradiate light from the surface of the filled restorative material, that is, from a position far from the tooth. There is. However, due to the shrinkage accompanying polymerization, a stress that tends to rise from the interface with the tooth acts, and this tends to cause a gap between the tooth and the filling restorative material. Various dental adhesives that exhibit extremely strong adhesive strength have been proposed to counter this polymerization shrinkage stress, but the dental condition varies from individual to individual or even to the same person, so such dental Even if the adhesive is used, it is not always possible to obtain perfect adhesion to every tooth. Accordingly, there has also been a demand for a dental composite resin that has as small a polymerization shrinkage as possible and hardly generates a gap due to the polymerization shrinkage even if sufficient adhesive strength cannot be obtained depending on the state of teeth. Furthermore, since such an adhesive requires a complicated technique for obtaining a high adhesive force, and causes an increase in cost, it has been desired to simplify the adhesive.

  In short, as a dental filling and restorative material, there is a demand for the development of a material capable of obtaining a satisfactory restoration state without being inhibited by polymerization by oxygen and having as little polymerization shrinkage as possible.

  As a polymerizable material that is not subjected to polymerization inhibition by oxygen, a cationically polymerizable material is conventionally known. Examples of such cationically polymerizable compounds include vinyl ether compounds, epoxy compounds, oxetane compounds, bicycloorthoester compounds, spiroorthoester compounds, and spiroorthocarbonate compounds (for example, Non-Patent Document 1).

  Among these, the vinyl ether compound is a compound that polymerizes and cures very rapidly. However, since the polymerization type is an addition polymerization type, the above-described problem of polymerization shrinkage cannot be solved.

  On the other hand, an epoxy compound, an oxetane compound, a bicycloorthoester compound, a spiroorthoester compound, and a spiroorthocarbonate compound are ring-opening polymerizable compounds and have an advantage of less polymerization shrinkage. In particular, bicycloorthoester compounds, spiroorthoester compounds, and spiroorthocarbonate compounds are also called non-shrinkable monomers, and are excellent compounds that have little or no shrinkage during polymerization. However, these non-shrinkable monomers alone have extremely low polymerizability, and it requires long-time light irradiation or heating to cure the polymer, which is not suitable for dental applications that are frequently polymerized and cured in the oral cavity. Is appropriate.

  Compared with these non-shrinkable monomers, epoxy compounds and oxetane compounds have relatively good curability, and several proposals have been made for use as a component in dental cationic curable compositions. As such a technique, a system using a combination of a cationically polymerizable epoxy compound and a compound having a hydroxyl group (for example, see Patent Document 1), or a system using an epoxy compound and / or an oxetane compound (for example, Patent Document 2). Have been proposed).

JP-A-11-130945 Japanese National Patent Publication No. 10-508067 Radtech Study Group, “Current Status and Prospects of UV / EV Curing Technology”, CMC Publishing Co., Ltd., December 27, 2002, p. 45-48

  However, even in a dental curable composition containing these epoxy compounds as a main component, there is a problem that sufficient gelation time is not yet obtained. In the polymerization and curing of the curable composition, the time required for the polymerization to be almost completely cured (curing time) and the time for the polymerization to progress to the extent that fluidity is lost (gelation time) are also important. . If the gelation time is long, it is easy to place deformation in the process of polymerization and curing. For example, when it is used as a dental filling restoration material, it does not become a cured body of the desired shape, or it is used as an adhesive In many cases, the position of the adherend is displaced. In particular, the epoxy compound has a long gel time.

  Therefore, the present invention is a cationic polymerization curable composition that is not subject to polymerization inhibition by oxygen, has little polymerization shrinkage, and has a short curing time and gelation time, and is used for dental applications that are often used in the oral cavity. It is an object to provide a cationic curable composition that can be used.

  As a result of diligent research to solve the above-mentioned problems, the present invention significantly reduces both curing time and gelation time by adding a small amount of a bicycloorthoester compound to an oxetane compound, and further polymerizes by blending a bicycloorthoester compound. As a result of finding that shrinkage is reduced and further studying it, the present invention has been completed.

  That is, the present invention relates to a curable composition comprising (I) a cationic polymerization initiator and (II) a cationic polymerizable compound, wherein the (II) cationic polymerizable compound has a number of oxetane functional groups per molecule. A mole of oxetane compound having B, and B mole of bicycloorthoester compound having b bicycloorthoester functional groups per molecule, and (a × A) :( b × B) is 99. It is a cationic curable composition for dental use in the range of 99: 0.01 to 50:50.

  The dental cation-curable composition of the present invention has a much lower level of polymerization shrinkage than dental materials using a conventionally known (meth) acrylate-based radical polymerizable monomer, and therefore has a better restoration state. Easy to get. Further, since there is no polymerization inhibition by oxygen, it is not necessary to polish the surface in order to remove the unpolymerized layer after polymerization / curing. Furthermore, since both the curing time and the gelation time are short, the polymerization and curing can be carried out in a short time, so that even if used in the oral cavity, there is no great burden on the patient.

  The cationic curable composition of the present invention includes (I) a cationic polymerization initiator and (II) a cationic polymerizable compound.

  The (I) cationic polymerization initiator is not particularly limited, and any known cationic polymerization initiator may be used. As such cationic polymerization initiators, Lewis acids or Bronsted acids, or compounds that generate Lewis acids or Bronsted acids by heating or light irradiation are known. It is particularly preferable to employ a so-called photoacid generator that generates a Lewis acid or a Bronsted acid by light irradiation because it can be polymerized quickly in an environment such as the oral cavity.

  Examples of the photoacid generator include diaryl iodonium salt compounds, sulfonium salt compounds, sulfonic acid ester compounds, and halomethyl-substituted S-triazine conductors.

  Among these, diaryliodonium salt compounds and sulfonium salt compounds are excellent in that the polymerization activity is particularly high. Specific examples of diaryliodonium salt compounds include diphenyliodonium, bis (p-chlorophenyl) iodonium, ditolyliodonium, bis (p-tert-butylphenyl) iodonium, p-isopropylphenyl-p-methylphenyliodonium, Bis (m-nitrophenyl) iodonium, p-tert-butylphenylphenyliodonium, p-methoxyphenylphenyliodonium, bis (p-methoxyphenyl) iodonium, p-octyloxyphenylphenyliodonium, p-phenoxyphenylphenyliodonium, etc. Cation and chloride, bromide, p-toluenesulfonate, trifluoromethanesulfonate, tetrafluoroborate, tetrakispentafluorophenyl volley And diaryl iodonium salt compounds comprising anions such as tetrakispentafluorophenyl gallate, hexafluorophosphate, hexafluoroarsenate and hexafluoroantimonate.

  Among these, p-toluene sulfonate, trifluoromethane sulfonate, tetrafluoroborate, tetrakispentafluorophenylborate, tetrakispentafluorophenyl gallate, hexafluorophosphate, hexagonal from the viewpoint of solubility in polymerizable monomers. A compound having fluoroarsenate or hexafluoroantimonate as an anion can be suitably used, and it has low nucleophilicity, and can be stably stored as a mixture with a polymerizable monomer without light irradiation. A compound having fluoroantimonate, tetrakispentafluorophenylborate or tetrakispentafluorophenylgallate as an anion can be preferably used.

  Examples of sulfonium salt compounds include dimethylphenacylsulfonium, dimethylbenzylsulfonium, dimethyl-4-hydroxyphenylsulfonium, dimethyl-4-hydroxynaphthylsulfonium, dimethyl-4,7-dihydroxynaphthylsulfonium, dimethyl-4,8- Cations such as dihydroxynaphthylsulfonium, triphenylsulfonium, p-tolyldiphenylsulfonium, p-tert-butylphenyldiphenylsulfonium, diphenyl-4-phenylthiophenylsulfonium, chloride, bromide, p-toluenesulfonate, trifluoromethanesulfonate , Tetrafluoroborate, tetrakispentafluorophenylborate, tetrakispentafluorophenylgallate, hexaful Examples thereof include sulfonium salt compounds composed of anions such as orophosphate, hexafluoroarsenate and hexafluoroantimonate.

  These photoacid generators may be used singly or in combination as needed. The amount of these photoacid generators used is not particularly limited as long as the polymerization can be initiated by light irradiation, but an appropriate rate of polymerization progress and various physical properties of the resulting cured product (for example, weather resistance) In general, 0.001 to 10 parts by mass, preferably 0.05 to 5 parts by mass is used with respect to 100 parts by mass of the cationic polymerizable monomer. .

  The photoacid generator as described above usually has many compounds that do not absorb in the near ultraviolet to visible range, and a special light source is often required to excite the polymerization reaction. Therefore, it is preferable that a compound having absorption in the near ultraviolet to visible region is further added as a sensitizer in addition to the photoacid generator.

  Examples of the compound used as such a sensitizer include acridine dyes, benzoflavine dyes, condensed polycyclic aromatic compounds such as anthracene and perylene, and phenothiazine.

  Among these sensitizers, a condensed polycyclic aromatic compound is preferable in terms of good polymerization activity, and a structure in which a saturated carbon atom having at least one hydrogen atom is bonded to the condensed polycyclic aromatic ring. Condensed polycyclic aromatic compounds having are preferred.

  Specific examples of such condensed polycyclic aromatic compounds having a structure in which a saturated carbon atom having at least one hydrogen atom is bonded to a condensed polycyclic aromatic ring include 1-methylnaphthalene and 1-ethylnaphthalene. 1,4-dimethylnaphthalene, acenaphthene, 1,2,3,4-tetrahydrophenanthrene, 1,2,3,4-tetrahydroanthracene, benzo [f] phthalane, benzo [g] chroman, benzo [g] isochroman, N-methylbenzo [f] indoline, N-methylbenzo [f] isoindoline, phenalene, 4,5-dimethylphenanthrene, 1,8-dimethylphenanthrene, acephenanthrene, 1-methylanthracene, 9-methylanthracene, 9-ethylanthracene , 9-cyclohexylanthracene, 9,10-dimethyl Luanthracene, 9,10-diethylanthracene, 9,10-dicyclohexylanthracene, 9-methoxymethylanthracene, 9- (1-methoxyethyl) anthracene, 9-hexyloxymethylanthracene, 9,10-dimethoxymethylanthracene, 9- Dimethoxymethylanthracene, 9-phenylmethylanthracene, 9- (1-naphthyl) methylanthracene, 9-hydroxymethylanthracene, 9- (1-hydroxyethyl) anthracene, 9,10-dihydroxymethylanthracene, 9-acetoxymethylanthracene 9- (1-acetoxyethyl) anthracene, 9,10-diacetoxymethylanthracene, 9-benzoyloxymethylanthracene, 9,10-dibenzoyloxymethylanthracene, 9 -Ethylthiomethylanthracene, 9- (1-ethylthioethyl) anthracene, 9,10-bis (ethylthiomethyl) anthracene, 9-mercaptomethylanthracene, 9- (1-mercaptoethyl) anthracene, 9,10-bis (Mercaptomethyl) anthracene, 9-ethylthiomethyl-10-methylanthracene, 9-methyl-10-phenylanthracene, 9-methyl-10-vinylanthracene, 9-allylanthracene, 9,10-diallylanthracene, 9-chloro Methyl anthracene, 9-bromomethylanthracene, 9-iodomethylanthracene, 9- (1-chloroethyl) anthracene, 9- (1-bromoethyl) anthracene, 9- (1-iodoethyl) anthracene, 9,10-dichloromethylanthracene 9,10-dibromomethylanthracene, 9,10-diiodomethylanthracene, 9-chloro-10-methylanthracene, 9-chloro-10-ethylanthracene, 9-bromo-10-methylanthracene, 9-bromo-10 -Ethylanthracene, 9-iodo-10-methylanthracene, 9-iodo-10-ethylanthracene, 9-methyl-10-dimethylaminoanthracene, acanthrene, 7,12-dimethylbenz (a) anthracene, 7,12- Dimethoxymethylbenz (a) anthracene, 5,12-dimethylnaphthacene, collanthrene, 3-methylcholanthrene, 7-methylbenzo (a) pyrene, 3,4,9,10-tetramethylperylene, 3,4,9, 10-tetrakis (hydroxymethyl) perylene, bio Nsuren, Isoviolanthrone Ren, 5,12-dimethyl-naphthacene, 6,13-dimethyl pentacene, 8,13- dimethyl penta Fen, 5,16- dimethyl hexamethylene Sen, 9,14- dimethyl hexa Fen and the like.

  Examples of the condensed polycyclic aromatic compound other than the above include naphthalene, phenanthrene, anthracene, naphthacene, benz [a] anthracene, pyrene, perylene and the like.

  Among these condensed polycyclic aromatic compounds, a compound having absorption in the visible range is preferable and a compound having maximum absorption in the visible range, which can excite polymerization with visible light in consideration of harm to the living body. Is more preferable. Further, these condensed polycyclic aromatic compounds may be used in combination with a plurality of compounds as necessary.

  The addition amount of the condensed polycyclic aromatic compound also varies depending on the other components to be combined and the kind of the polymerizable monomer, but the amount of the condensed polycyclic aromatic compound is usually 0 with respect to 1 mol of the above-mentioned photoacid generator. 0.001 to 20 mol, and preferably 0.005 to 10 mol.

  Furthermore, it is preferable to add an oxidized photoradical generator in addition to the condensed polycyclic aromatic compound because the polymerization activity is further improved. An oxidized photoradical generator is a compound that generates radicals when excited by light irradiation, and is a so-called hydrogen abstraction type radical generator that generates radicals by extracting hydrogen from a hydrogen donor by excitation. Generates radicals by causing self-cleavage (self-cleaving radical generator), and then the radicals withdrawing electrons from the electron donor, and radicals that are excited by light irradiation and withdraw electrons directly from the electron donor. The photoradical generator is a mechanism that generates active radical species by excitation by light irradiation, such as the following. These oxidation type photo radical generators are not particularly limited, and known compounds may be used. However, in terms of higher polymerization activity when irradiated with light compared to other compounds, hydrogen abstraction type light radical generators may be used. A radical generator is preferred, and among them, a diaryl ketone compound, an α-diketone compound or a ketocoumarin compound is particularly preferred.

  Specific examples of the diaryl ketone compound include 4,4-bis (dimethylamino) benzophenone, 9-fluorenone, 3,4-benzo-9-fluorenone, 2-dimethylamino-9-fluorenone, and 2-methoxy-9-fluorenone. 2-chloro-9-fluorenone, 2,7-dichloro-9-fluorenone, 2-bromo-9-fluorenone, 2,7-dibromo-9-fluorenone, 2-nitro-9-fluorenone, 2-acetoxy-9 -Fluorenone, benzanthrone, anthraquinone, 1,2-benzanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 1-dimethylaminoanthraquinone, 2,3-dimethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone 1,5-dichloroanthraquinone, 1,2-dimethoxyanthraquinone, 1,2-diacetoxy-anthraquinone, 5,12-naphthacenequinone, 6,13-pentacenequinone, xanthone, thioxanthone, 2,4-dimethylthioxanthone, 2,4 -Diethylthioxanthone, 2-chlorothioxanthone, 9 (10H) -acridone, 9-methyl-9 (10H) -acridone, dibenzosuberenone and the like can be mentioned.

  Specific examples of α-diketone compounds include camphorquinone, benzyl, diacetyl, acetylbenzoyl, 2,3-pentadione, 2,3-octadione, 4,4′-dimethoxybenzyl, 4,4′-oxybenzyl, 9,10-phenanthrenequinone, acenaphthenequinone, etc. are mentioned.

  Examples of ketocoumarin compounds include 3-benzoylcoumarin, 3- (4-methoxybenzoyl) coumarin, 3-benzoyl-7-methoxycoumarin, 3- (4-methoxybenzoyl) 7-methoxy-3-coumarin, and 3-acetyl- Examples thereof include 7-dimethylaminocoumarin, 3-benzoyl-7-dimethylaminocoumarin, 3,3′-coumarinoketone, 3,3′-bis (7-diethylaminocoumarino) ketone, and the like.

  These oxidized photoradical generators can be used alone or in admixture of two or more. Moreover, although the addition amount varies depending on the other components to be combined and the kind of the polymerizable monomer, the photoradical generator is usually 0.001 to 20 mol relative to 1 mol of the photoacid generator described above. It is preferable that it is 005-10 mol.

  The cationic curable composition of the present invention comprises (II) a cation polymerizable compound, an oxetane compound having an oxetane functional group (hereinafter simply referred to as an oxetane compound), and a bicycloorthoester compound having a bicycloorthoester functional group (hereinafter simply referred to as a cation composition). Bicycloorthoester compound) must be included.

  The oxetane functional group is represented by the following formula (1)

(In the formula, R represents a hydrogen atom or a monovalent group.)
Is a four-membered ether (oxetane ring) functional group represented by the formula (2):

Wherein R ′ and R ″ each independently represent a hydrogen atom or a monovalent group, and R ″ ′, R ″ ″ and R ″ ″ ′ may each independently have a bond or a substituent. Shows good alkylene group.)
The functional group which consists of a bicyclo ortho-ester ring shown by these.

  The oxetane compound used in the present invention is not particularly limited as long as it is a compound capable of cationic polymerization, and a known compound can be used. In the above formula (1), R is the 3-position of the oxetane ring. A compound bonded to is preferred. Specific examples of the oxetane compound include trimethylene oxide, 3-methyl-3-oxetanylmethanol, 3-ethyl-3-oxetanylmethanol, 3-ethyl-3-phenoxymethyloxetane, 3,3-diethyloxetane, 3 Those having one oxetane ring such as ethyl-3- (2-ethylhexyloxy) oxetane, 1,4-bis (3-ethyl-3-oxetanylmethyloxy) benzene, 4,4'-bis (3- Ethyl-3-oxetanylmethyloxy) biphenyl, 4,4′-bis (3-ethyl-3-oxetanylmethyloxymethyl) biphenyl, ethylene glycol bis (3-ethyl-3-oxetanylmethyl) ether, diethylene glycol bis (3- Ethyl-3-oxetanylmethyl) ether, bi (3-ethyl-3-oxetanylmethyl) Jifenoeto, trimethylolpropane tris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, or a compound shown below

And compounds having two or more oxetane rings. These oxetane compounds may be used in combination.

  In particular, those having two or more oxetane functional groups in one molecule are suitably used from the viewpoint of physical properties of the obtained cured product.

  In addition, the bicycloorthoester compound is not particularly limited as long as it is a compound capable of cationic polymerization, and any known compound can be used. In the formula (2), R ″ ′ and R ″ ″ are methylene groups. A compound in which R ″ ″ ′ is a bond or a methylene group is preferable.

  Specific examples of typical bicycloorthoester compounds include 2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-2,6,7-trioxabicyclo [2,2 , 2] octane, 1-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-2,6,7-trioxabicyclo [2,2,2] octane, 4 -Methyl-2,6,7-trioxabicyclo [2,2,2] octane, 4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-ethyl -2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1,4-dimethyl -2,6,7-trioxabicyclo [2,2,2] octane, 1,4-diethi -2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4 -Ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-hydroxymethyl-4 -Methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-hydroxymethyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4- Hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, Ethyl-4-hydroxymethyl-2,6,7- Lioxabicyclo [2,2,2] octane, 1-isopropyl-4-hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-hydroxyethyl) -2, 6,7-trioxabicyclo [2,2,2] octane, 1- (1-hydroxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- ( 1-hydroxyethyl) -4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane 1-methoxymethyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methoxymethyl-4-ethyl-2,6,7-trioxabicyclo [2,2 , 2] octane, 4-methoxymethyl-2,6,7 Trioxabicyclo [2,2,2] octane, 1-methyl-4-methoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-methoxymethyl-2, 6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-methoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-methoxyethyl) ) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-methoxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2,2] octane 1- (1-methoxyethyl) -4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethoxymethyl-2,6,7-trioxabicyclo [2,2 , 2] octane, 1-ethoxymethyl-4-methyl-2 , 7-trioxabicyclo [2,2,2] octane, 1-ethoxymethyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4-ethoxymethyl-2,6 , 7-trioxabicyclo [2,2,2] octane, 1-methyl-4-ethoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-ethoxymethyl -2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-ethoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1 -Ethoxyethyl) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-ethoxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2, 2] Octane, 1- (1-ethoxyethyl) -4-ethyl 2,6,7-trioxabicyclo [2,2,2] octane, 1-benzyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-benzyloxymethyl-4- Methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-benzyloxymethyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4- Benzyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-benzyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-benzyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-benzyloxymethyl-2,6,7-trioxabicyclo [2, 2,2] octane, 1- ( -Benzyloxyethyl) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-benzyloxyethyl) -4-methyl-2,6,7-trioxabicyclo [2, 2,2] octane, 1- (1-benzyloxyethyl) -4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-phenyloxymethyl-2,6,7- Trioxabicyclo [2,2,2] octane, 1-phenyloxymethyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-phenyloxymethyl-4-ethyl- 2,6,7-trioxabicyclo [2,2,2] octane, 4-phenyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-phenyloxy Methyl-2,6,7-trioxa Bicyclo [2,2,2] octane, 1-ethyl-4-phenyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-phenyloxymethyl-2, 6,7-trioxabicyclo [2,2,2] octane, 1- (1-phenyloxyethyl) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-phenyl) Oxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-phenyloxyethyl) -4-ethyl-2,6,7-trioxabicyclo [ 2,2,2] octane, 1-acetoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-acetoxymethyl-4-methyl-2,6,7-trioxabicyclo [ 2,2,2] octane, 1-acetoxy Methyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4-acetoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl -4-acetoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-acetoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane 1-isopropyl-4-acetoxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-acetoxyethyl) -2,6,7-trioxabicyclo [2,2 , 2] octane, 1- (1-acetoxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-acetoxyethyl) -4-ethyl-2 , 6,7-Trioxabicyclo [2,2,2] o Kutan, 1-methacryloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methacryloxymethyl-4-methyl-2,6,7-trioxabicyclo [2,2, 2] Octane, 1-methacryloxymethyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4-methacryloxymethyl-2,6,7-trioxabicyclo [2, 2,2] octane, 1-methyl-4-methacryloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-methacryloxymethyl-2,6,7- Trioxabicyclo [2,2,2] octane, 1-isopropyl-4-methacryloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-methacryloxyethyl)- , 6,7-trioxabicyclo [2,2,2] octane, 1- (1-methacryloxyethyl) -4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, -(1-Methacryloxyethyl) -4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-benzoyloxymethyl-2,6,7-trioxabicyclo [2,2 , 2] octane, 1-benzoyloxymethyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-benzoyloxymethyl-4-ethyl-2,6,7-trio Xabibicyclo [2,2,2] octane, 4-benzoyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-benzoyloxymethyl-2,6,7 -Trioxabicyclo [2,2 , 2] octane, 1-ethyl-4-benzoyloxymethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-benzoyloxymethyl-2,6,7-trio Xabibicyclo [2,2,2] octane, 1- (1-benzoyloxyethyl) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-benzoyloxyethyl) -4 -Methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-benzoyloxyethyl) -4-ethyl-2,6,7-trioxabicyclo [2,2,2 ] Octane, 1-vinyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-vinyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane 1-vinyl-4-ethyl-2,6,7-to Oxabicyclo [2,2,2] octane, 1-chloromethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-chloromethyl-4-methyl-2,6,7-trio Xabicyclo [2,2,2] octane, 1-chloromethyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-bromomethyl-2,6,7-trioxa Bicyclo [2,2,2] octane, 1-bromomethyl-4-methyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-bromomethyl-4-ethyl-2,6,7- Trioxabicyclo [2,2,2] octane, 4-chloromethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-chloromethyl-2,6,7- Trioxabicyclo [2,2,2] octane, 1-ethyl-4 Chloromethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-chloromethyl-2,6,7-trioxabicyclo [2,2,2] octane, 4- Bromomethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-methyl-4-bromomethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl- 4-bromomethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-isopropyl-4-bromomethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-bromoethyl) -2,6,7-trioxabicyclo [2,2,2] octane, 1- (1-bromoethyl) -4-methyl-2,6,7-trioxabicyclo [2,2, 2] Octane, 1- (1-bromoethyl)- Ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 2,6,7-trioxabicyclo [2,2,1] heptane, 1-methyl-2,6,7-trio Xabicyclo [2,2,1] heptane, 1-ethyl-2,6,7-trioxabicyclo [2,2,1] heptane, 1-phenyl-2,6,7-trioxabicyclo [2,2 , 1] heptane, 1-hydroxymethyl-2,6,7-trioxabicyclo [2,2,1] heptane, etc., a compound having one bicycloorthoester functional group,

A compound having two bicycloorthoester functional groups such as

And compounds having three or more bicycloorthoester functional groups in one molecule. A plurality of different types of these bicycloorthoester compounds may be used.

  The greatest feature of the present invention is that the amount of the oxetane compound and the bicycloorthoester compound is adjusted so that the amount of the oxetane functional group and the amount of the bicycloorthoester functional group in the composition are in a specific range. is there. That is, when the oxetane compound has a oxetane functional group per molecule and the bicycloorthoester compound has b bicycloorthoester functional groups per molecule, (a × A) :( b × B) It is necessary to blend A mole of the oxetane compound and B mole of the bicycloorthoester compound so as to be in the range of 99.99: 0.01 to 50:50.

  As described above, in the present invention, a single oxetane compound may be used, or a plurality of different types may be used. When a single oxetane compound is used, or when only an oxetane compound having the same number of oxetane functional groups is used, the number of oxetane functional groups per molecule is the number of oxetane functional groups possessed by the oxetane compound. be equivalent to. When a plurality of compounds having different numbers of oxetane functional groups per molecule is used, the number of oxetane functional groups is an average value obtained from the blending amount (ratio) and the number of functional groups of each compound. It is. For example, when equimolar amounts of an oxetane compound having only one oxetane functional group and an oxetane compound having two oxetane functional groups are used, an oxetane compound having 1.5 oxetane functional groups per molecule is used. Calculate as Similarly, when a 1: 3 molar ratio of an oxetane compound having only one oxetane functional group and an oxetane compound having two oxetane functional groups is used, 1.75 oxetane functional groups per molecule are used. It is calculated as using the oxetane compound having.

  The average number of functional groups per molecule of the bicycloorthoester compound may be calculated in the same manner as described above.

  In the present invention, each of the oxetane compound and the bicycloorthoester compound always has at least one oxetane functional group and bicycloorthoester functional group, so that neither a nor b is less than 1. . Considering the availability of the compound, the operability such as the viscosity of the curable composition of the present invention, the mechanical properties of the cured product after curing, both a and b are in the range of 1 to 5. Is preferable, and it is more preferable that it is in the range of 1.5 to 3.

  As described above, in the present invention, it is essential that (a × A) :( b × B) is in the range of 99.99: 0.01 to 50:50. By setting it in this range, both the gelation time and the curing time can be made much faster than when the cationically polymerizable compound is only an oxetane compound (the above ratio is 100: 0). On the other hand, when the bicycloorthoester compound is blended so that the number of bicycloorthoester functional groups is larger than 50:50 (the ratio is higher), the curing will be slower than when the compound is not blended at all. The bicycloorthoester compound is extremely poor in cationic polymerizability, and usually hardly photocured with the compound alone. In terms of obtaining a better curing rate, (a × A) :( b × B) is preferably in the range of 99.9: 0.1 to 60:40, and from the viewpoint of physical properties of the cured product and the like. More preferably, it is the range of 99: 1 to 70:30.

  On the other hand, as with the bicycloorthoester functional group, a compound having an orthospiroester functional group or an orthospirocarbonate functional group, which is another ring-opening polymerizable functional group having almost no polymerization shrinkage, may be combined with an oxetane compound, Curing time will not be accelerated, and gelation time will not be as fast as when a bicycloorthoester compound is used. In addition, when a compound having an epoxy functional group is combined with a compound having an oxetane functional group, the curing time is fast, but there is a problem that gelation is not so fast. There is a problem that the polymerization shrinkage is larger than that of the ortho ester functional group. Also, compounds having an epoxy functional group tend to be highly toxic, and from this point of view, it is not preferable for dental use.

  In addition, a combination of a bicycloorthoester compound and a compound having an epoxy functional group, an orthospiroester functional group, or an orthospirocarbonate functional group can give only a curable composition that is inferior to the curable composition of the present invention.

  In addition to the oxetane compound and the bicycloorthoester compound, the cationically curable composition of the present invention, in addition to the oxetane compound and the bicycloorthoester compound, as long as the functional group ratio is maintained, A compound having a cationic polymerizable functional group may be blended, but as the proportion of the other cationic polymerizable functional group in the cationic polymerizable functional group in the curable composition increases, the curing rate may become slower. Since the gelation time becomes longer or the polymerization shrinkage rate becomes larger, the proportion of other functional groups when the total of all cationic polymerizable functional groups in the cationic curable composition is 100 mol% Is preferably less than 30 mol%, preferably less than 10 mol%, more preferably less than 5 mol%. Other cationically polymerizable functional group other than oxetane functionality and bicyclo orthoester functional groups is particularly preferably substantially absent.

  Moreover, it is also possible to mix | blend an addition polymerization type radical polymerizable monomer, such as a (meth) acrylate type monomer, as needed. By blending the radically polymerizable monomer, the apparent curing time can be further shortened. On the other hand, the addition polymerization type radical polymerizability has a large polymerization shrinkage. When the radical polymerizable monomer is blended, the blending amount is preferably 30% by mass or less with respect to a total of 100% by mass of the cationic polymerizable monomer and the radical polymerizable monomer. % Or less is preferable.

  Specific examples of such radical polymerizable monomers include methyl (meth) acrylate, glycidyl (meth) acrylate, 2-cyanomethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, and allyl (meth) acrylate. 2-hydroxyethyl mono (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, nonaethylene glycol di (meth) acrylate, propylene glycol di (meth) Acrylate, dipropylene glycol di (meth) acrylate, 2,2-bis [4- (meth) acryloyloxyethoxyphenyl] propane, 2,2-bis [4- (meth) acryloyloxyethoxye Xylphenyl] propane, 2,2-bis {4- [3- (meth) acryloyloxy-2-hydroxypropoxy] phenyl} propane, 1,4-butanediol di (meth) acrylate, 1,3-hexanediol di ( And (meth) acrylate monomers such as (meth) acrylate, urethane di (meth) acrylate, and trimethylolpropane di (meth) acrylate.

  In addition to the polymerization initiator and the polymerizable monomer, the dental cation curable composition of the present invention can be blended with other components known as a compounding component of the dental curable composition.

  Typical other compounding ingredients include (III) filler. By blending a filler with the dental cationic curable composition of the present invention, polymerization shrinkage can be further reduced. In addition, by using a filler, it is possible to improve the operability of the curable composition before curing, or to improve the mechanical properties after curing, especially useful as a filling restoration material for dental use. Will be expensive.

  When a filler is blended with the dental cation-curable composition of the present invention, the type and blending amount of the filler may be appropriately set according to the use of the composition. For example, when the dental cation curable composition of the present invention is used as a filling restorative material, a known filler may be blended as a filler for the dental filling restorative material.

  More specifically, inorganic particles (hereinafter referred to as “inorganic filler”) such as quartz, silica, alumina, silica titania, silica zirconia, lanthanum glass, barium glass, and strontium glass can be used. Furthermore, you may use the granular organic-inorganic composite particle (organic-inorganic composite filler) obtained by mixing these inorganic fillers and a polymerizable monomer in advance, forming a paste, polymerizing, and pulverizing. In addition, X-ray contrast property can also be provided by using what contains heavy metals, such as a zirconia, as an inorganic filler.

  The particle diameter and shape of these fillers are not particularly limited, and spherical or irregular particles having an average particle diameter of 0.01 μm to 100 μm, which are generally used as dental materials, can be appropriately used depending on the purpose. That's fine. Further, the refractive index of these fillers is not particularly limited, and those in the range of 1.4 to 1.7 which the fillers of general dental compositions have can be used without limitation.

  The blending amount when the above filler is blended with the cationic curable composition of the present invention is not particularly limited, but when used as a dental filling restorative material, it is 50 per 100 parts by weight of the polymerizable monomer. To 1500 parts by mass, preferably 70 to 1000 parts by mass. Further, these fillers such as inorganic fillers and organic-inorganic composite fillers may be used alone, or a plurality of fillers having different materials, particle sizes, shapes, etc. may be used in combination. When using as a dental filling / restoring material, it is particularly preferable to mainly use an inorganic filler in terms of excellent mechanical properties after curing.

  If necessary, polymethyl methacrylate, polyethyl methacrylate, methyl methacrylate-ethyl methacrylate copolymer, cross-linked polymethyl methacrylate, cross-linked polyethyl methacrylate, ethylene-vinyl acetate copolymer, styrene-butadiene copolymer, acrylonitrile -It is also possible to mix | blend the particle | grains (organic filler) which consist of organic polymers, such as a styrene copolymer and an acrylonitrile-butadiene-styrene copolymer, as a filler.

  Further, the dental cationic curable composition of the present invention includes a polymerization inhibitor, a polymerization inhibitor, an antioxidant, an ultraviolet absorber, a dye, an antistatic agent, a pigment, a fragrance, and the like within a range not impairing the effects of the present invention. Known additives such as organic solvents and thickeners may be blended.

  The dental cationic polymerizable composition of the present invention is particularly preferably used as the dental filling / restoration material as described above, but is not limited thereto, and other uses such as a dental adhesive and a denture base material. Can also be used.

  The manufacturing method of the dental cation-curable composition of the present invention is not particularly limited, and a known manufacturing method may be adopted as appropriate. Specifically, a predetermined amount of a cationic polymerization initiator, a cationic polymerizable compound, and other blending components blended as necessary, which constitute the dental cationic curable composition of the present invention, are weighed and mixed. That's fine.

  The packaging form of the dental cationic curable composition of the present invention is not particularly limited, and may be appropriately determined in consideration of its purpose and storage stability. For example, when a photocationic polymerization initiator is blended as a cationic polymerization initiator, all the components constituting the dental cation-curable composition of the present invention may be made into one package in a light-shielded state. On the other hand, if a component that can start cationic polymerization at room temperature without light irradiation is used as a polymerization initiator, it can be divided into two or more packages to prevent polymerization and curing during storage. A form in which both are mixed immediately before use is preferred.

  As a means for curing the dental cationic curable composition of the present invention, a known polymerization means may be appropriately employed according to the polymerization initiation mechanism of the used cationic polymerization initiator. Specifically, a carbon arc, a xenon lamp, A metal halide lamp, a tungsten lamp, a fluorescent lamp, light irradiation with a light source such as sunlight, helium cadmium laser, and argon laser, heating using a heating polymerizer, or a combination of these is used without any limitation. In the case of polymerization by light irradiation, the irradiation time varies depending on the wavelength of the light source, the intensity, the shape and material of the cured body, and therefore may be determined in advance by preliminary experiments. It is preferable to adjust the blending ratio of the various components so that the range is about 5 to 60 seconds. Similarly, the heating time and heating temperature may be determined in advance by preliminary experiments.

  Further, as described above, when the cationic curable composition of the present invention is used as a dental filling restorative material, there is substantially no surface unpolymerized layer. It is not necessary to polish and remove the polymerized layer, but polishing or the like may be performed to approximate the shape of the teeth.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to the examples. The names and structures of the compounds used in the text and in the examples are as follows.
1. Oxetane compounds

2. Bicycloorthoester compounds

3. Cationic polymerizable compounds (monomers) other than oxetane compounds or bicycloorthoesters

4). Radical polymerizable monomer

5). Photoacid generator

6). Fused polycyclic aromatic compounds

7). 7. Oxidized photoradical generator CQ: camphorquinone Others DMPT: N, N-dimethyl-p-toluidine Further, the physical property evaluation methods shown in the text and in the examples are as follows.

(1) Curing time A curable composition is built up on a glass plate with a diameter of about 6 mm and a height of 3 mm. Visible light was irradiated. At that time, the hardness of the upper surface and the side surface of the built-up structure was examined so as not to block the irradiation light with a needle having a thickness of about 0.4 mm, and the time when the needle stopped sticking to the entire built-up structure was defined as the curing time.

(2) Gelation time The prepared curable composition was built up on a glass plate in a disk shape having a diameter of 6 mm and a height of 3 mm. Next, the curable composition was irradiated with a dental irradiator (TOKUSO POWER LITE, manufactured by Tokuyama Dental Co., Ltd.) at a distance of about 5 mm from the glass surface direction on which the curable composition was placed. A probe was brought into contact with the built-up curable composition from the opposite side of the glass surface while performing this light irradiation, and the point at which fluidity was not observed in this portion was defined as the gel time.

(3) Polymerization shrinkage ratio A SUS plunger having a diameter of 3 mm and a height of 7 mm was filled with a SUS plunger having a diameter of 3 mm and a height of 4 mm to make the hole height 3 mm. This was filled with a curable composition and pressed from above with a polypropylene film. The film was faced down and placed on a glass table equipped with a dental irradiator, and a short needle capable of measuring the movement of a fine needle was brought into contact with the SUS plunger. Polymerization and curing were performed with a dental irradiator, and the shrinkage (%) 10 minutes after the start of irradiation was calculated from the movement distance of the short needle in the vertical direction.

(4) Flexural strength and flexural modulus The curable composition was filled in a 2 × 2 × 25 mm mold and cured by light irradiation for 1.5 minutes with a light irradiator. After storing the cured product at 37 ° C. overnight, using an autograph (manufactured by Shimadzu Corporation), the distance between the fulcrums is 20 mm and the crosshead speed is 0.5 mm / min. The cured product was measured and the average value was calculated.

Example 1
OXT-121 (manufactured by Toa Gosei Co., Ltd.) and BOE-1 were blended while adjusting the amount such that BOE-1 was 0.1053 mol with respect to 1 mol of OXT-121. In this case, since OXT-121 is a bifunctional oxetane compound, a is 2, and since BOE-1 is a monofunctional bicycloorthoester compound, b is 1, and the functional group ratio is (a × A) :( b × B) = (2 × 1) :( 1 × 0.1053) = 95: 5.

  To 100 parts by mass of the polymerizable compound mixture, 1 part by mass of IMDPI, 0.1 part by mass of DMBAn, and 0.4 parts by mass of CQ were added, and stirred and dissolved in the dark to form matrix A.

  On the other hand, 20 g of a 7: 3 mass ratio mixture of spherical silica-zirconia (average particle size 0.5 μm) and spherical silica-titania (average particle size 0.1 μm) was suspended in 80 ml of hydrochloric acid adjusted to pH 4.0. While stirring, 1.2 g of 3-glycidyloxypropyltrimethoxysilane was added dropwise. After stirring for 1 hour, water was distilled off with an evaporator, and the obtained solid was pulverized with a mortar and then dried at 80 ° C. under reduced pressure for 15 hours. After drying, the obtained powder was designated as inorganic filler a.

  The prepared inorganic filler a and the matrix A were mixed in an agate mortar so that the inorganic filler content was 76% by mass, and the mixture was degassed under vacuum to remove bubbles and obtain a dental filling restorative material. .

  When the physical properties of this dental filling / restoring material were measured, the gelation time was 3 seconds, the curing time was 9 seconds, and the polymerization shrinkage ratio was 1.1%.

Comparative Example 1
A dental filling / restoration material was prepared in the same manner as in Example 1 except that OXT-121 was used in place of the mixture of OXT-121 and BOE-1, and various physical properties were measured. As a result, the gelation time was 7 seconds, the curing time was 33 seconds, and the polymerization shrinkage ratio was 1.1%.

Examples 2-4
Various physical properties were measured by changing the mixing ratio of OXT-121 and BOE-1 at the ratio shown in Table 1. In the table, the numerical value in the column of the oxetane compound is (a × A) when (a × A) + (b × B) is 100, and the numerical value in the column of the bicycloorthoester compound is (b × B). Show. The measured physical properties are shown in Table 1.

Comparative Example 2
In place of the mixture of OXT-121 and BOE-1, except that all BOE-1 was used, the dental filling restorative material was adjusted in the same manner as in Example 1, and various physical properties were measured. It was not cured at all even by light irradiation.

Examples 5-8
Instead of BOE-1, BOE-2 was used, and various physical properties were measured by changing the mixing ratio of this and OXT-121 at a ratio shown in Table 1. In the table, the numerical value in the column of the oxetane compound is (a × A) when (a × A) + (b × B) is 100, and the numerical value in the column of the bicycloorthoester compound is (b × B). Show. The measured physical properties are shown in Table 1.

Comparative Example 3
A dental filling / restoration material was prepared and various physical properties were measured in the same manner as in Example 1 except that OXT-221 was changed to 100% instead of the mixture of OXT-121 and BOE-1. As a result, the gelation time was 6 seconds, the curing time was 30 seconds, and the polymerization shrinkage rate was 1.2%.

Examples 9-12
Instead of OXT-121, OXT-221 was used, and various physical properties were measured by changing the mixing ratio of this to BOE-1 at a ratio shown in Table 1. In the table, the numerical value in the column of the oxetane compound is (a × A) when (a × A) + (b × B) is 100, and the numerical value in the column of the bicycloorthoester compound is (b × B). Show. The measured physical properties are shown in Table 1.

  As understood from the results shown in Table 1 above, by blending the bicycloorthoester compound so that the bicycloorthoester functional group is in a specific range with respect to the oxetane functional group of the oxetane compound, the oxetane compound alone, Alternatively, both the gelation time and the curing time can be made much shorter than in the case of the bicycloorthoester compound alone, so that it can be made extremely excellent as a dental curable composition used in the oral cavity.

Comparative Examples 4-11
Predetermined amounts of various cationically polymerizable compounds were blended so that the functional group ratios shown in Table 2 were obtained, and a photocationic polymerization initiator was added at the same ratio as in Example 1 to obtain a dental filling restorative material. The gelation time, curing time and polymerization shrinkage of these compositions were measured and the results are shown in Table 2. In addition, the numerical value of the column of each compound in a table | surface is a value which shows the ratio of the cation polymerizable functional group derived from each compound when the sum total of all the cation polymerizable functional groups in a composition is set to 100, The calculation method is the same as in the case of the oxetane functional group and the bicycloorthoester functional group.

  As can be understood by comparing these comparative examples and the above-mentioned examples, the effect of speeding up the gelation can be obtained even when a cationically polymerizable compound other than the bicycloorthoester compound is added to the oxetane compound. Much smaller than the compound.

  On the other hand, even if a bicycloorthoester compound is blended with an epoxy compound or a vinyl ether compound, the gelation time is not shortened, but rather the gelation time tends to be long. That is, the effect of the present invention is specific to the combination of an oxetane compound and a bicycloorthoester compound.

  In addition, as shown as Comparative Examples 10 and 11, the vinyl ether compound is a compound having an extremely fast gelation time. However, since it is not a ring-opening polymerization but an addition polymerization type compound, the polymerization shrinkage ratio is large. Therefore, the solution of the problem of polymerization shrinkage that occurs when a (meth) acrylate radically polymerizable monomer is used is hardly solved even when the vinyl ether compound is used.

Comparative Example 12
50 parts by mass of Bis-GMA, which is a radical polymerizable compound, and 50 parts by mass of 3G were mixed, and 1 part by mass of DMPT and 0.4 part by mass of CQ were added to this mixture and stirred and dissolved in the dark.

  On the other hand, 20 g of a 7: 3 weight ratio mixture of spherical silica-zirconia (particle size 0.5 μm) and spherical silica-titania (particle size 0.1 μm) was suspended in 80 ml of hydrochloric acid adjusted to pH 4.0 and stirred. Then, 1.26 g of 3-methacryloxypropyltrimethoxysilane was added dropwise. After stirring for 1 hour, water was distilled off with an evaporator, and the obtained solid was pulverized with a mortar and then dried at 80 ° C. under reduced pressure for 15 hours. After drying, the obtained powder was used as inorganic filler b. This is mixed with the radical polymerizable monomer mixture in an agate mortar so that the inorganic filler content is 76% by mass, and the mixture is degassed under vacuum to remove air bubbles and remove conventional bubbles. Obtained material.

  When various physical properties of this dental filling / restoring material were measured, the polymerization shrinkage was as large as 2.0%, and the portion in contact with air was sticky, and the uncured portion remained.

  Further, the bending strength and the bending elastic modulus of the dental filling / restoration materials used in Example 2 and Comparative Examples 1, 4, 8, and 12 were measured. The results are shown in Table 3.

Claims (4)

  (I) In the curable composition containing a cationic polymerization initiator and (II) a cationic polymerizable compound, the (II) cationic polymerizable compound is an A mole of an oxetane compound having a oxetane functional group per molecule. And B mole of a bicycloorthoester compound having b bicycloorthoester functional groups per molecule, and (a × A) :( b × B) is 99.99: 0.01˜ Dental cationic curable composition characterized by being in the range of 50:50.   (I) The cationic curable composition for dental use according to claim 1, wherein the cationic polymerization initiator is a photocationic polymerization initiator.   The dental cation-curable composition according to claim 1 or 2, further comprising (III) a filler. The dental cation-curable composition according to claim 1, which is a dental filling restorative material.