JP4268482B2 - Photopolymerization initiator - Google Patents

Description

  The present invention relates to a novel photopolymerization initiator useful for a photoresist material, a printing plate making material, a hologram material, particularly a dental material, and a one-paste photopolymerization dental composite resin containing the same. More specifically, it is stable to ambient light (light with low intensity) compared to conventional photopolymerization initiators, but it can be remarkably shortened by intense light irradiation using an illuminator such as a halogen lamp or a xenon lamp. The present invention provides a photopolymerization initiator that can quickly complete polymerization, obtain higher cured product properties, and whose activity does not decrease even when stored for a long period of time, as well as a one-paste photopolymerizable dental composite resin. is there.

  Various proposals have been made regarding photopolymerization initiators that generate radicals or ionic species by light irradiation and polymerize polymerizable unsaturated compounds or cyclic compounds. In general, a compound that absorbs light and decomposes itself to generate a polymerization active species, and a system in which an appropriate sensitizer is combined are widely studied and used.

  Examples of the former include acylphosphine oxide compounds and α-diketone compounds, and examples of the latter include well-known combinations of α-diketone compounds and tertiary amine compounds. It is useful in the field.

For example, in the field of dental materials, the photopolymerization initiator is added to a paste-like composition composed mainly of a (meth) acrylate monomer called a composite resin and an inorganic filler (filler), and the composite Used to make the resin photopolymerizable. The composite resin is used after being filled and molded with a tooth in a paste state and then cured by irradiating light with a dental light irradiator or the like (hereinafter referred to as "irradiating light to be polymerized and cured" In general, such irradiation is performed using a light source having an output power of about 100 to 1500 mW / cm ² in a wavelength range of about 360 to 500 nm which is a main absorption range of the α-diketone compound. From a certain distance). Specifically, after filling the above-mentioned paste-like composition into the cavity of the tooth to be repaired in the dental clinic and forming it into a tooth shape, it is polymerized and cured by irradiating irradiation light using a dedicated light irradiator. In the dental laboratory, the above composition is built in the shape of a tooth to be restored on a plaster model, and this is polymerized and cured by light irradiation to obtain a cured product. Teeth are repaired by a method such as adhering to a tooth using a dental adhesive (for example, Non-Patent Document 1).

  However, when the above α-diketone compound and a tertiary amine compound are used in combination as a photopolymerization initiator, the viscosity of the paste increases during operations such as filling and building up, There was a problem that operation became difficult.

That is, operations such as filling and building up are performed by human beings while confirming the shape, and since the color tone of the cured product finally obtained by polymerization is also important, it is usually a dental light or fluorescent light that illuminates the oral cavity. It is necessary to perform under white light such as a room light such as a lamp (hereinafter, these lights used for human visual recognition are referred to as “ambient light”. The light intensity at 360 to 500 nm, which is the main absorption region of the α-diketone compound, is 1 mW / cm ² or less, depending on the light source. Less than a few percent of light). On the other hand, in recent years, as a dental photopolymerization initiator, those having a polymerization initiating ability with light in the visible range having little influence on the human body are used (for example, α-diketones typical for dental use). Camphorquinone is a yellow compound having a maximum absorption wavelength at 468 nm). The polymerization initiator in which a tertiary amine compound is combined with the α-diketone compound has a good polymerization activity with respect to light in the visible range. In response to this, it begins to harden sensitively. Therefore, when working under ambient light, which is indispensable for operations such as filling and building up, this high polymerization activity works adversely, and the curing proceeds gradually, resulting in the problems described above. Is.

  The phenomenon of an increase in the viscosity of the paste during operations such as filling and building up can be avoided by reducing the amount of photopolymerization initiator used or adding a large amount of polymerization inhibitor. However, when such a method is applied, sufficient curing does not occur even when the irradiation light is irradiated for the same amount of time as before, and the strength of the resulting cured body is reduced. Problems such as a large amount of unpolymerized monomer remaining often occur. For this reason, in order to fully advance polymerization hardening, it is necessary to lengthen the irradiation time of irradiation light. However, the composite resin is often used in the oral cavity of a patient, and taking a long irradiation time not only takes time for operation, but also has a problem of imposing a great burden on the patient.

Further, even if the environmental light stability is improved by reducing the addition amount of the photopolymerization initiator, the curing time can be shortened and the strength of the cured product can be improved by increasing the light intensity of the irradiation light. However, in order to obtain a high light intensity, a large amount of energy is required. Even if it is visible light, too strong light may cause damage to the human body, especially the eyes. Furthermore, since a light source with high light intensity generally tends to generate heat, there is a concern about damage to the living body due to the heat. Therefore, in recent years, the energy of the irradiation light source has been reduced, and a light irradiator of about ²⁰ to 100 mW / cm ² using a laser diode or the like has started to spread. Accordingly, it is practically difficult to solve the above problem by simply reducing the amount of photopolymerization initiator added.

  That is, in the past composition using the conventional photopolymerization initiator, it is difficult to balance the stability against ambient light and the reaction activity against irradiation light, that is, curing does not occur in light as weak as ambient light, On the other hand, when a strong light irradiation is performed by a dental light irradiator or the like, it was not possible to obtain a material that hardens rapidly. Furthermore, in order to reduce the burden on the patient, it is simultaneously required to obtain sufficient curability in a shorter time than before.

  In order to solve such problems, various photopolymerization initiators other than the combination of an α-diketone compound and a tertiary amine compound have been studied. For example, (meth) acrylate polymerizable monomer, acylphosphine A photocurable dental material comprising an oxide polymerization initiator and an amine compound is known (for example, Patent Document 1). Although this dental material has sufficient ambient light stability and high cured material properties, the light irradiation time required for curing is comparable to conventional photocurable dental materials, and there is a need for further shortening of the time. It did not meet. It is also known to use an allyl iodonium salt, a sensitizer, and an electron donor as a polymerization initiator component (for example, Patent Document 2). In the composition using this photopolymerization initiator, the irradiation light irradiation time required for polymerization and curing is shorter than that of the prior art. However, in order to shorten the time required for the dental treatment, curing in a further short time is desired. Moreover, when the said photoinitiator is used, the big improvement is not seen by environmental light stability.

  On the other hand, an s-triazine compound substituted with a trihalomethyl group is a compound that generates an acid upon irradiation with light, and has been conventionally used as a polymerization initiator for photocationic polymerization, but in recent years, it has been combined with other components. It has begun to be used as an initiator for radical polymerization. For example, radical polymerization initiators composed of photoacid generators such as aryl borate compounds and s-triazine compounds substituted with a trihalomethyl group and dyes that absorb visible light have been proposed (for example, Patent Documents 3 and 4). ).

  In these photopolymerization initiators, the photoacid generator decomposes to generate an acid, and this acid decomposes the aryl borate compound to generate active radical species, thereby causing polymerization. The active radical species generated by the decomposition of the aryl borate compound have extremely high polymerization activity, and are less susceptible to polymerization inhibition by oxygen than conventional radical polymerization initiators. Also, the curing time is short, and even against weak light. It has the advantage of having sufficient activity and is extremely useful as a dental adhesive.

  However, having sufficient activity even for weak light means that the stability to ambient light is low, and such a photopolymerization initiator is used as a photopolymerization initiator for dental composite resins. It is not very desirable to use as.

Edited by Hiroyasu Hosoda, “Basics and Clinical Studies of Photopolymerization Composite Resin”, Nippon Dental Press, February 10, 1986, p. 9-20 JP 2000-16910 A JP-A-63-273602 JP-A-1-138204 JP-A-9-3109

The present inventors have solved the above-mentioned problems, have high stability with respect to light as weak as ambient light (less than 1 mW / cm ^{2 at} 360 to 500 nm), and also halogen lamps, xenon lamps, or laser diodes. Novel photopolymerization initiator useful for dental composite resins that can be polymerized in a very short time and have good cured properties by intense light irradiation (about 20 mW / cm ² or more) by an irradiator such as As a photopolymerization initiator comprising an α-diketone compound, an s-triazine compound substituted with a trihalomethyl group, and an amine compound, the inventors have already proposed (Japanese Patent Application No. 2003-68737). In this photopolymerization initiator, by using an aromatic amine compound and an aliphatic amine compound in combination as an amine compound, the cured product is converted to ultraviolet light such as sunlight, compared to the case of using only the aromatic amine compound. Coloring when exposed is small, and the curing rate can be made faster than when only an aliphatic amine compound is used.

  However, according to further studies by the present inventors, N, N-dimethylaminoethyl methacrylate is used as an aliphatic amine in a photopolymerizable composition in which the above-mentioned photopolymerization initiator is blended with a (meth) acrylate monomer. When an aliphatic amine compound such as N, N-diethylaminoethyl methacrylate is blended, it has been found that there is a problem that the polymerization activity decreases with time during storage at a relatively high temperature of about 50 ° C. .

  The dental material is often transported by a private car or the like when transporting to a dental clinic or the like, but it is not uncommon for the temperature in the car to exceed 50 ° C. in the summer. In addition, even at a temperature lower than 50 ° C., it is predicted that a decrease in polymerization activity will similarly occur during long-term storage.

Therefore, the present invention has high stability with respect to ambient light of less than 1 mW / cm ² , and the polymerization can be completed in a very short time if intense light irradiation of 20 mW / cm ² or more is performed by an irradiator. An object of the present invention is to provide a novel photopolymerization initiator useful for a dental composite resin capable of obtaining good cured product properties and having excellent storage stability.

  The present inventors have intensively studied to solve the above problems. As a result, in the photopolymerization catalyst comprising the α-diketone compound, the s-triazine compound substituted with a trihalomethyl group, and an amine compound, when a specific triazin-2-one compound is adopted instead of the s-triazine compound. The present inventors have found that the storage stability is improved and completed the present invention.

  That is, the present invention provides (A) the following general formula (1)

（式中、Ｒ ^２ 及びＲ ^３ は各々独立に、置換基を有していてもよいアルキル基であり、Ｒ ^４ は水素原子、置換基を有していてもよいアルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいアルケニル基、置換基を有していてもよいアルコキシ基、又は置換基を有していても良いアルキルオキシカルボニル基である。）で示される芳香族アミン化合物からなる光重合開始剤である。 (Wherein, R ¹ is a hydrogen atom, a hydroxyl group or an organic group having 1 to 15 carbon atoms, and X is a halogen atom), 3,3,5-triazin-2 (1H) -one compound, (B) α-diketone compound, (C) the following general formula (2)

(In the formula, R ² and R ³ are each independently an alkyl group which may have a substituent, and R ⁴ has a hydrogen atom, an alkyl group which may have a substituent, or a substituent. An aryl group which may be substituted, an alkenyl group which may have a substituent, an alkoxy group which may have a substituent, or an alkyloxycarbonyl group which may have a substituent. It is a photoinitiator which consists of an aromatic amine compound shown by these .

  The photopolymerization initiator of the present invention has higher stability against ambient light (weak light) as long as it has the same curing rate with respect to strong irradiation light as compared with conventionally known photopolymerization initiators. If the light stability is equivalent, the polymerization and curing can be completed much faster. And by using a substituted triazin-2 (1H) -one compound, good storage stability can be obtained, and the polymerization activity hardly decreases even when stored at a high temperature for a long time. Furthermore, the obtained cured product has high mechanical strength, and can be particularly suitably used as a photopolymerizable composite resin that is a dental filler.

  The (3) component 1,3,5-triazin-2 (1H) -one compound used in the photopolymerization initiator of the present invention is characterized by being substituted with at least one trihalomethyl group.

  In the general formula (1), the halogen atom represented by X is preferably a chlorine, bromine, or iodine halogen atom, but a compound having a trichloromethyl group substituted by a chlorine atom is preferably used.

In the general formula (1), R ¹ is an organic group having 1 to 15 carbon atoms. Specific examples of the organic group include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an n-hexyl group, and an i-hexyl group. An unsubstituted alkyl group having ˜15; an alkyl group substituted with a halogen having 1 to 15 carbon atoms such as a trichloromethyl group, tribromomethyl group, α, α, β-trichloroethyl group; phenyl group, p-methoxyphenyl Group, p-methylthiophenyl group, p-chlorophenyl group, 4-biphenylyl group, naphthyl group, 4-methoxy-1-naphthyl group and other aryl group which may have a substituent having 6 to 15 carbon atoms; vinyl group , An alkenyl group which may have a substituent having 2 to 15 carbon atoms such as an allyl group and a 2-phenylethenyl group; and a substituent having 7 to 15 carbon atoms such as a benzyl group and a phenethyl group. Aral Le group; methoxy group, an ethoxy group, etc. alkoxy group which may have a substituent having 1 to 15 carbon atoms such as butoxy group.

Among the compounds represented by the general formula (1), it is more preferable to use a compound in which R ¹ is an alkyl group which may have a substituent in terms of excellent polymerization activity, and a trihalogen-substituted methyl group. (Trihalomethyl group) is particularly preferred.

  Specific examples of the substituted triazin-2 (1H) -one compound represented by the general formula (1) include 4,6-bis (trichloromethyl) -1,3,5-triazin-2 (1H) -one. 4,6-bis (tribromomethyl) -1,3,5-triazin-2 (1H) -one, 4-phenyl-6-trichloromethyl-1,3,5-triazin-2 (1H) -one 4-phenyl-6-tribromomethyl-1,3,5-triazin-2 (1H) -one, 4- (p-chlorophenyl) -6-trichloromethyl-1,3,5-triazine-2 (1H ) -One, 4- (m-methoxyphenyl) -6-trichloromethyl-1,3,5-triazin-2 (1H) -one, 4- (p-methoxyphenyl) -6-trichloromethyl-1,3 , 5-Triazin-2 (1H) -one, 4-pheni Ethenyl-6-trichloromethyl-1,3,5-triazin-2 (1H) -one, 4-phenylethenyl-6-tribromomethyl-1,3,5-triazin-2 (1H) -one, 4 -(4-biphenylyl) -6-trichloromethyl-1,3,5-triazin-2 (1H) -one, 4-methoxy-6-trichloromethyl-1,3,5-triazin-2 (1H) -one Etc. can be mentioned.

  The triazin-2 (1H) -one compound may be used alone or in combination of two or more. Moreover, the general addition amount is about 0.005-10 weight part with respect to 100 weight part of polymerizable monomers, More preferably, it is about 0.03-5 weight part.

  The second component in the photopolymerization initiator of the present invention is (B) an α-diketone compound. As the α-diketone compound, known compounds can be used without any limitation. Specific examples of the α-diketone compounds include camphorquinones such as camphorquinone, camphorquinonecarboxylic acid, camphorquinonesulfonic acid; diacetyl, acetylbenzoyl, 2,3-pentadione, 2,3-octadione, 9,10 -Phenanthrene quinone, acenaphthene quinone, etc. can be mentioned.

  The α-diketone compound to be used may be appropriately selected and used depending on the wavelength and intensity of light used for the polymerization, the time of light irradiation, or the type and amount of other components to be combined, alone or in combination of two or more. It can also be used. Among these, considering use in dental use, a compound having a maximum absorption wavelength in the visible light range is preferable, and camphorquinones are generally preferably used, and camphorquinone is particularly preferable. Further, although the addition amount varies depending on the other components to be combined and the kind of the polymerizable monomer, it is usually 0.01 to 10 parts by weight, more preferably 0.03 to 5 parts by weight based on 100 parts by weight of the polymerizable monomer. The range is parts by weight. The larger the amount, the shorter the curing time by irradiation light, while the smaller the amount, the better the ambient light stability.

（式中、Ｒ ^２ 及びＲ ^３ は各々独立に、置換基を有していてもよいアルキル基であり、Ｒ ^４ は水素原子、置換基を有していてもよいアルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいアルケニル基、置換基を有していてもよいアルコキシ基、又は置換基を有していても良いアルキルオキシカルボニル基である。）で示される芳香族アミン化合物である。当該芳香族アミン化合物は、窒素原子に結合した有機基のうちの一つが芳香族基であるアミン化合物である。本発明の効果である速い硬化速度は、このような芳香族アミン化合物を用いた場合にはじめて発現する。同じアミン化合物であっても、芳香族アミン化合物に替えて、窒素原子に結合した有機基として芳香族基を有しない（水素原子又は脂肪族基だけが結合している）脂肪族アミン化合物を用いると、ほとんど硬化は進行しない。 The third component in the photopolymerization initiator of the present invention is (C) the following general formula (2)

(In the formula, R ² and R ³ are each independently an alkyl group which may have a substituent, and R ⁴ has a hydrogen atom, an alkyl group which may have a substituent, or a substituent. An aryl group which may be substituted, an alkenyl group which may have a substituent, an alkoxy group which may have a substituent, or an alkyloxycarbonyl group which may have a substituent. It is an aromatic amine compound shown by these . The aromatic amine compound is an amine compound in which one of organic groups bonded to a nitrogen atom is an aromatic group. The fast curing speed that is the effect of the present invention is manifested only when such an aromatic amine compound is used. Even if the same amine compound is used, an aliphatic amine compound that does not have an aromatic group (only a hydrogen atom or an aliphatic group is bonded) as an organic group bonded to a nitrogen atom is used instead of the aromatic amine compound. Hardening hardly progresses.

The aromatic amine compound is an amine compound in which one aromatic group and two aliphatic groups are bonded to a tertiary nitrogen atom (hereinafter also referred to as a tertiary aromatic amine compound), and is a known one. There can use without limitation, high Polymerization activity and less odor due to its low volatility, more availability is easy.

As the alkyl group which may have a top Symbol substituent, a methyl group, an ethyl group, n- propyl group, i- propyl, n- butyl group, an unsubstituted alkyl group such as n- hexyl group; chloro Examples thereof include alkyl groups substituted with halogen such as methyl group and 2-chloroethyl group; those having 1 to 6 carbon atoms such as alkyl group substituted with hydroxyl group such as 2-hydroxyethyl group. Examples of the aryl group that may have a substituent include those having 6 to 12 carbon atoms such as a phenyl group, p-methoxyphenyl, p-methylthiophenyl group, p-chlorophenyl group, 4-biphenylyl group, Examples of the alkenyl group which may have a substituent include those having 2 to 12 carbon atoms such as vinyl group, allyl group and 2-phenylethenyl group, which may have a substituent. , A methoxy group, an ethoxy group, a butoxy group and the like having 1 to 10 carbon atoms are exemplified, and the alkyloxycarbonyl group which may have a substituent includes a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group And those having 1 to 10 carbon atoms in the alkyloxy group such as amyloxycarbonyl group and isoamyloxycarbonyl group.

As the R ² and R ^3, preferably an alkyl group having 1 to 6 carbon atoms, more preferably an unsubstituted alkyl group having 1 to 3 carbon atoms. Specific examples of such an alkyl group again include a methyl group, an ethyl group, and an n-propyl group.

In addition, R ⁴ is more preferably a para bond, and further preferably an alkyloxycarbonyl group.

Specific examples of such aromatic amine compounds in which R ⁴ is an alkyloxycarbonyl group bonded to the para-position include methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, and p-dimethylaminobenzoic acid. Examples include propyl, amyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, propyl p-diethylaminobenzoate, and the like.

  Specific examples of the other aromatic amine compounds represented by the general formula (2) include N, N-dimethylaniline, N, N-dibenzylaniline, N, N-dimethyl-p-toluidine, N, N-diethyl-p-toluidine, N, N-di (β-hydroxyethyl) -p-toluidine and the like can be mentioned.

  These aromatic amine compounds may be used alone or in combination of two or more. Moreover, the general compounding quantity is 0.01-5 weight part with respect to 100 weight part of polymerizable monomers, More preferably, it is 0.02-3 weight part.

  In addition, if an aromatic amine compound is blended, an aliphatic amine compound may be added in addition thereto, but in that case, the polymerization activity tends to decrease as the addition amount increases, so the addition amount can be as much as possible. Less is preferable. Specifically, the aliphatic amine compound is 0.5 mol or less, preferably 0.1 mol or less, particularly preferably, per 1 mol of the 1,3,5-triazin-2 (1H) -one compound to be blended. Is not included at all.

  The photopolymerization initiator of the present invention is used for polymerizing a polymerizable monomer, and may be used as a polymerization initiator for any known photopolymerizable composition without particular limitation. There is a strong demand for both excellent ambient light stability and curing speed, and since the amount used per time is small, it is a photopolymerization type dental composite that is often stored for a long time after production. It is preferably used as a polymerization initiator for a resin.

  The photopolymerizable dental composite resin is a material used to repair a tooth that has been lost due to caries or the like, and is generally composed of a (meth) acrylate polymerizable monomer and an inorganic filler. As a component, a photopolymerization initiator is blended in order to polymerize and cure by irradiation with visible light. Moreover, in order to make operability favorable, there are many materials that are made of a one-paste type material that does not need to be mixed at the time of use.

  The photopolymerization dental composite resin, which is a typical example of a photopolymerizable composition using the photopolymerization initiator of the present invention, will be described in more detail below.

  The polymerizable monomer contained in the photopolymerizable dental composite resin includes a (meth) acrylate polymerizable monomer having no acidic group (sulfonic acid group, carboxyl group, phosphoric acid residue, etc.) The body is preferably used from the viewpoints of curing speed, mechanical properties of the cured body, water resistance, color resistance, etc., and in particular, a polyfunctional (meth) acrylate-based polymerizable monomer having a plurality of polymerizable functional groups. A monomer is preferred. As the polyfunctional (meth) acrylate polymerizable monomer, known ones can be used without particular limitation. Examples of those generally used preferably include those shown in the following (I) to (III).

(I) Bifunctional polymerizable monomer (i) Aromatic compound type 2,2-bis (methacryloyloxyphenyl) propane, 2,2-bis [4- (3-methacryloyloxy) -2-hydroxypropoxy Phenyl] propane (hereinafter abbreviated as bis-GMA), 2,2-bis (4-methacryloyloxyphenyl) propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (hereinafter referred to as D-2. 6E), 2,2-bis (4-methacryloyloxydiethoxyphenyl) propane, 2,2-bis (4-methacryloyloxytetraethoxyphenyl) propane, 2,2-bis (4-methacryloyloxypentaethoxy) Phenyl) propane, 2,2-bis (4-methacryloyloxydipropoxyphenyl) propyl Pan, 2 (4-methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxytriethoxyphenyl) propane, 2 (4-methacryloyloxydipropoxyphenyl) -2- (4-methacryloyloxytriethoxyphenyl) propane, 2 , 2-bis (4-methacryloyloxypropoxyphenyl) propane, 2,2-bis (4-methacryloyloxyisopropoxyphenyl) propane and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, Methacrylates such as 3-chloro-2-hydroxypropyl methacrylate or vinyl monomers having —OH groups such as acrylates corresponding to these methacrylates, and diisocyanates Diaducts obtained from addition with a diisocyanate compound having an aromatic group such as methylbenzene and 4,4′-diphenylmethane diisocyanate.

(Ii) Aliphatic compound-based ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate (hereinafter abbreviated as 3G), tetraethylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,3-butanediol Dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate Such as methacrylates or vinyl monomers having —OH groups such as acrylates corresponding to these methacrylates, and hexamethylene Diadducts obtained from adducts with diisocyanate compounds such as isocyanate, trimethylhexamethylene diisocyanate, diisocyanate methylcyclohexane, isophorone diisocyanate, methylenebis (4-cyclohexylisocyanate); 1,2-bis (3-methacryloyloxy-2-hydroxy Propoxy) ethyl and the like.

(II) Trifunctional polymerizable monomer Methacrylates such as trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate, and acrylates corresponding to these methacrylates.

(III) Tetrafunctional polymerizable monomer Pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate and diisocyanate methylbenzene, diisocyanate methylcyclohexane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, methylenebis (4-cyclohexylisocyanate), 4 Diadduct obtained from an adduct of a diisocyanate compound such as 1,4-diphenylmethane diisocyanate and tolylene-2,4-diisocyanate and glycidol dimethacrylate.

  These polyfunctional (meth) acrylate polymerizable monomers may be used in combination of a plurality of types as required.

  Further, if necessary, monofunctional (meth) acrylate-based monomethacrylates such as methacrylates such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, glycidyl methacrylate, and acrylates corresponding to these methacrylates. A polymerizable monomer other than the above-mentioned (meth) acrylate monomer may be used.

  In addition, since the aromatic amine compound which is an essential component of the photopolymerization initiator of the present invention tends to react with an acid to form a salt and lose polymerization activity, (meth) acrylic acid, p- (meth) acryloyl Polymerizable monomers having an acidic group such as oxybenzoic acid, 10-methacryloyloxydecamethylenemalonic acid, 2-hydroxyethyl hydrogenphenyl phosphate are inevitable as impurities such as (meth) acrylate monomers. It is preferable not to mix as much as possible, except in the case of mixing in. When the amount of impurities is about a general amount, the polymerization activity can be maintained by using a large amount of the amine compound. Moreover, you may mix | blend an aliphatic amine compound for the purpose of neutralization of such an acidic compound. However, in this case, the preferred compounding amount of the above-described amine compound is an amount excluding the amount neutralized with such an acid to form a salt.

  Further, as the inorganic filler, known inorganic fillers can be used without limitation as fillers for dental composite resins, but typical inorganic fillers are exemplified by quartz, silica, alumina, silica titania, Examples thereof include metal oxides such as silica zirconia, lanthanum glass, barium glass, and strontium glass. If necessary, a known cation-eluting inorganic filler such as silicate glass and fluoroaluminosilicate glass may be blended as a dental inorganic filler. These may be used alone or in combination of two or more.

  Moreover, you may use the granular organic-inorganic composite filler obtained by adding a polymerizable monomer to these inorganic fillers beforehand, making it paste-form, polymerizing, and grind | pulverizing.

  The particle size of these fillers is not particularly limited, and fillers having an average particle size of 0.01 μm to 100 μm (particularly preferably 0.01 to 5 μm) generally used as dental materials are used depending on the purpose. It can be used as appropriate. Further, the refractive index of the filler is not particularly limited, and those in the range of 1.4 to 1.7 which a general dental inorganic filler has can be used without limitation, and can be appropriately set according to the purpose. Good. A plurality of inorganic fillers having different particle size ranges and different refractive indexes may be used in combination.

  Furthermore, when a spherical inorganic filler is used among the above fillers, the surface smoothness of the resulting cured product is increased, and an excellent dental composite resin can be obtained.

  It is desirable to treat the inorganic filler with a surface treating agent typified by a silane coupling agent in order to improve the compatibility with the polymerizable monomer and improve the mechanical strength and water resistance. The surface treatment method may be performed by a known method. Examples of the silane coupling agent include methyltrimethoxysilane, methyltriethoxysilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, vinyltrichlorosilane, vinyltriethoxysilane, Vinyltris (β-methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, hexamethyldisilazane and the like are preferably used.

  The proportion of these fillers may be appropriately determined in consideration of the viscosity (operability) when mixed with the polymerizable monomer and the mechanical properties of the cured body, depending on the purpose of use. Is used in an amount of 50 to 1500 parts by weight, preferably 70 to 1000 parts by weight, based on 100 parts by weight of the polymerizable monomer.

  In addition, pigments, fluorescent pigments, dyes, ultraviolet absorbers may be added to prevent discoloration to ultraviolet rays in order to match the color tone of the teeth, and other additives known as components of dental composite resins may be added. You may mix | blend in the range which does not affect the effect of invention.

  The method for producing such a photopolymerizable composite resin is not particularly limited, and any known photopolymerizable composite resin production method may be followed. In general, a predetermined amount of each component to be blended may be weighed out under light shielding and kneaded until uniform.

  The preferred blending amount when blending the photopolymerization initiator of the present invention into the dental composite resin is that the components (A) to (C) constituting the photopolymerization initiator are within the above range, and the total amount thereof. However, it is 0.01-20 weight part with respect to 100 weight part of polymerizable monomers, Furthermore, 0.05-10 weight part, Especially preferably, it is the range of 0.1-3 weight part.

  The photopolymerization initiator of the present invention is particularly preferably used in the one-paste photopolymerization dental composite resin as described above. However, as a photopolymerizable composition mixed with a polymerizable monomer, other uses are possible. Can also be used. Although it does not specifically limit as the use, For example, a dental adhesive agent and denture base material, Furthermore, a photoresist material, printing plate-making material, a hologram material etc. are mentioned. In these general applications, in addition to the (meth) acrylate polymerizable monomer, the (meth) acrylate polymer is often used for ease of polymerization, viscosity adjustment, or other physical property adjustment. It is also possible to polymerize by mixing other polymerizable monomers other than the polymerizable monomer. Examples of these other polymerizable monomers include fumaric acid esters such as monomethyl fumarate, diethyl fumarate, diphenyl fumarate; styrene such as styrene, divinylbenzene, α-methylstyrene, α-methylstyrene dimer, or α -Methyl styrene derivatives; allyl compounds such as diallyl terephthalate, diallyl phthalate, diallyl diglycol carbonate, and the like. These polymerizable monomers can be used alone or in combination of two or more.

  Furthermore, you may mix | blend another well-known polymerization initiator with the photopolymerizable composition which mix | blended the photoinitiator of this invention in the range which does not impair the effect of this invention. Other polymerization initiator components include organic peroxides such as benzoyl peroxide and cumene hydroperoxide; + IV value or + V such as vanadium (IV) acetylacetonate, bis (maltolate) oxovanadium (IV), etc. Valent vanadium compounds; tetraphenyl boron sodium, tetraphenyl boron triethanolamine salt, tetraphenyl boron dimethyl-p-toluidine salt, tetrakis (p-fluorophenyl) boron sodium, butyltri (p-fluorophenyl) boron sodium, etc. Aryl borate compounds; coumarin dyes such as 3,3′-carbonylbis (7-diethylamino) coumarin, 7-hydroxy-4-methyl-coumarin; bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide , Bi Acylphosphine oxides such as (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide; benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin propyl ether; 2,4- Examples include thioxanthone derivatives such as diethoxythioxanthone, 2-chlorothioxanthone, and methylthioxanthone; benzophenone derivatives such as benzophenone, p, p′-dimethylaminobenzophenone, and p, p′-methoxybenzophenone. However, in order to obtain high ambient light stability, it is preferable that the aryl borate compounds and the organic peroxide be as small as possible. In addition, when a pigment such as a coumarin-based pigment is added in an amount that acts as a polymerization initiator, it has a great effect on the color tone of the photopolymerizable composition, and in dental composite resins that require high aesthetics. Tend to have a different color tone than the teeth.

  Moreover, it is also possible to add water, an organic solvent, a thickener, etc. to the photopolymerizable composition which mix | blended the photoinitiator of this invention in the range which does not reduce the performance according to the objective. Examples of the organic solvent include hexane, heptane, octane, toluene, dichloromethane, methanol, ethanol, and ethyl acetate. As the thickener, polymer compounds such as polyvinyl pyrrolidone, carboxymethyl cellulose, and polyvinyl alcohol, and highly disperse silica are used. Illustrated.

  When curing the photopolymerizable composition containing the photopolymerization initiator of the present invention, the same known light source as used to cure the α-diketone photopolymerization initiator may be used, In order to take advantage of the characteristics of the photopolymerization initiator of the present invention, which is relatively stable to low-intensity light irradiation and rapidly cures by high-intensity light irradiation above a certain level, a carbon arc, a xenon lamp, A visible light source such as a metal halide lamp, a tungsten lamp, an LED, a halogen lamp, a helium cadmium laser, and an argon laser is used without any limitation. Since the irradiation time varies depending on the wavelength and intensity of the light source and the shape and material of the cured body, it may be determined in advance through preliminary experiments.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, the abbreviations (in parentheses) of the compounds used in the following Examples and Comparative Examples are shown below.

(1) Abbreviations / abbreviations (A) 1,3,5-triazin-2 (1H) -one compound substituted with a trihalomethyl group, 4,6-bis (trichloromethyl) -1,3,5-triazine- 2 (1H) -On (BTTO)
4-phenyl-6-trichloromethyl-1,3,5-triazin-2 (1H) -one (PTTO)
(B) α-diketone camphorquinone (CQ)
(C) Aromatic amine compound / ethyl N, N-dimethyl p-benzoate (DMBE)
・ N, N-Dimethyl p-isoamyl benzoate (DMBI)
・ N, N-dimethyl p-toluidine (DMPT)
(D) Polymerizable monomer 2,2-bis [(3-methacryloyloxy-2-hydroxypropyloxy) phenyl] propane (bis-GMA)
2,2-bis (4- (methacryloyloxypolyethoxyphenyl) propane (D2.6E)
・ Triethylene glycol dimethacrylate (3G)
1,6-bis (methacrylethyloxycarbonylamino) trimethyloxane (UDMA)
(E) Inorganic filler, spherical silica-zirconia, γ-methacryloyloxytrimethoxysilane surface-treated product; average particle size; 0.5 μm (E-1)
Spherical silica-titania, γ-methacryloyloxytrimethoxysilane surface-treated product; average particle size: 0.08 μm (E-2)
(F) Other components 2,4,6-Tris (trichloromethyl) -s-triazine (TCT)
・ Triethanolamine (TEOA)
・ Hydroquinone monomethyl ether (HQME)
Moreover, the following methods were used for the measurement of the preparation method of photocurable composite resin, curing characteristics (environmental light stability, curing time), and mechanical strength of the cured product.

(1) Preparation method of photocurable composite resin A predetermined amount of a photopolymerization initiator and an inorganic filler were added to a polymerizable monomer, and the mixture was uniformly stirred and degassed under red light.

(2) Brightness of irradiated light The light intensity (mW / cm ² ) on the irradiated surface was a value obtained by measuring at a wavelength of 360 to 500 nm using UIT-101 manufactured by USHIO INC.

(3) Curing speed by irradiation light A polytetrafluoroethylene mold having a hole of 6 mmφ × 1.0 mm is filled with the prepared composite resin paste and pressed with a polypropylene film. Power Light, Tokuyama Dental Co., Ltd .; light output density 700 mW / cm ² ) was adhered to the polypropylene film and irradiated at intervals of 5 seconds, 10 seconds, 15 seconds and 5 seconds, and the hardness of the cured body at each irradiation time was determined. It touched with the hand and evaluated by the following references | standards. The light intensity on the irradiated surface at this time was 640 to 650 mW / cm ² .

  ○: Hardened sufficiently.

  (Triangle | delta): Although it hardens a little, it is a soft gel form.

  X: Not cured at all.

(4) Hardness of the cured body (Vickers hardness)
A mold made of polytetrafluoroethylene having a hole of 6 mmφ × 1.0 mm is filled with a paste and pressed with a polypropylene film, and a dental light irradiator (LUX · O · MAX, Akeda Dental Co .; light output density: 137 mW / cm ² ) Was adhered to a polypropylene film and irradiated for 10 seconds to prepare a cured product. The obtained cured product was obtained from the diagonal length of the indentation formed in the test piece with a load of 100 gf and a load holding time of 30 seconds using a Vickers indenter with a micro hardness tester (MHT-1 type manufactured by Matsuzawa Seiki Co., Ltd.). The light intensity on the irradiated surface at this time was 640 to 650 mW / cm ² .

(5) Evaluation of storage stability The prepared photocurable composite resin was stored in a light-shielded incubator set at 50 ° C., and Vickers hardness was measured by the same method as in (3) at regular intervals. The storage stability was evaluated from the change with time of the Vickers hardness value.

(6) Ambient light stability test The distance between the light source and the sample was set so that the surface of the paste-like curable composition sample was 10,000 lux. The illuminance measured with a illuminance meter (Digital Lux Meter FLX-1330, manufactured by Tokyo Glass Instrument Co., Ltd., having sensitivity at 400 to 700 nm) using a 15 W fluorescent lamp (manufactured by Matsushita Electric Co., Ltd., Palook) as the light source. The distance between the sample and the fluorescent lamp was set so that the illuminance was achieved. The light intensity on this irradiated surface was 0.4 mW / cm ² . 0.03 g of the prepared photocurable composite resin paste was weighed onto a polypropylene film, irradiated with the light from the fluorescent lamp for a predetermined time, and then the sample was crushed to measure the time when the inside of the sample started to harden. The irradiation time was 5 seconds. The longer this time is, the better the ambient light stability is, and a good operation margin time can be obtained.

(7) Bending strength Tosso Powerlite is filled with a curable composition in a stainless steel formwork and pressed with polypropylene, changing the place so that the entire surface is exposed to light for 10 seconds x 3 times. And was irradiated with light in close contact with polypropylene. Subsequently, it was made to adhere to polypropylene from the opposite side in the same manner and irradiated with light for 10 seconds × 3 times to obtain a cured product. Using # 800 water-resistant abrasive paper, the cured body was adjusted to a 2 × 2 × 25 mm prism shape, and this sample piece was mounted on a testing machine (manufactured by Shimadzu Corp., Autograph AG5000D). The 3-point bending fracture strength was measured at 1 mm / min.

Examples 1-5
BisGMA (60 parts by weight), 3G (40 parts by weight) polymerizable monomer 100 parts by weight, inorganic filler E-1 140 parts by weight, E-2 60 parts by weight, HQME 0 as a polymerization inhibitor A paste-like composition was prepared by stirring and mixing a photocurable composite resin composed of .15 parts by weight and a photopolymerization initiator shown in Table 1 in the dark using an agate mortar. The ambient light stability and curing speed of the above paste, the Vickers hardness and bending strength of the cured product were measured. The storage stability was also evaluated. The results are shown in Table 1.

Comparative Examples 1-5
As in Examples 1 to 5, a paste-like photocurable composite resin having the composition shown in Table 1 was prepared, and environmental light stability, curing speed, bending strength, and storage stability due to Vickers hardness were evaluated. In addition, the measurement of Vickers hardness was performed with the hardened | cured material obtained by making predetermined time of light irradiation into 10 second.

  As understood from Examples 1 to 5 and Comparative Examples 1 to 5, a photopolymerizable composition containing a photopolymerization initiator composed of a triazin-2-one compound, an α-diketone compound, and an aromatic amine compound is It had high ambient light stability, good curing speed, high bending strength, and even after storage at 50 ° C. for 14 days, the Vickers hardness was equivalent to the initial (0 day). Although not shown in the table, the composite resin of Example 1 had a Vickers hardness of 14 and a high ratio of about 2/3 of the initial value even after storage at 50 ° C. for 96 days.

  Comparative Example 1 is a case where the triazin-2-one compound, which is an essential component of the present invention, is not added. As understood from the comparison between Comparative Example 1 and Examples 1 to 4, when the triazin-2-one compound is not blended, the curing rate is slow, and the bending strength and Vickers hardness are low.

  In Comparative Example 2, a triazine compound was added instead of the triazin-2-one compound. From the comparison between Comparative Example 2 and Example 4, when the triazine compound is added, the initial curability is high and the curing speed is fast, but after storage at 50 ° C. for 14 days, the Vickers hardness is reduced to about half of the initial value. .

  Comparative Example 3 is a case where an aromatic amine which is an essential component of the present invention is not added. In this case, the curing rate was very slow and the curing hardly proceeded.

  Comparative Example 4 is an example in which triethanolamine which is an aliphatic amine compound is used instead of the aromatic amine compound. Even in this case, the curing hardly proceeded, and only a result equivalent to the case where no amine compound was blended was obtained.

Comparative Example 5 shows the result when no α-diketone was added, and the curing hardly progressed.

Claims (3)

(A) The following general formula (1)

(Wherein, R ¹ is a hydrogen atom, a hydroxyl group or an organic group having 1 to 15 carbon atoms, and X is a halogen atom), 3,3,5-triazin-2 (1H) -one compound, (B) α-diketone compound, (C) the following general formula (2)

(In the formula, R ² and R ³ are each independently an alkyl group which may have a substituent, and R ⁴ has a hydrogen atom, an alkyl group which may have a substituent, or a substituent. An aryl group which may be substituted, an alkenyl group which may have a substituent, an alkoxy group which may have a substituent, or an alkyloxycarbonyl group which may have a substituent. The photoinitiator which consists of an aromatic amine compound shown by these . A dental photopolymerizable composition containing the photopolymerization initiator according to claim 1. A one-paste photopolymerizable dental composite resin comprising the photopolymerization initiator according to claim 1, (D) a radical polymerizable monomer having no acidic group, and (E) an inorganic filler.