JP2002097388A - Inorganic filler for dental surface improving - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filler and a method of preparing the same having an excellent abrasive property and optical characteristics such as surface lubricative property or the like required for a dental composition and capable of concurrently imparting an excellent abrasion resistance, durability, mechanical strength or the like. SOLUTION: This inorganic filler is obtained by coating polyorganosiloxane to the surface of fine inorganic particles having average particle size of 0.01-5 μm. The method of preparing the inorganic filler includes (1) a wet grinding process fine grinding raw material inorganic particles into fine inorganic particles having average particle size of 0.01-5 μm or a wet dispersing process cracking agglomerates of inorganic particles comprising primary particles having average particle size of 0.01-5 μm into the primary particles and (2) a process forming a film of polyorganosiloxane on the surface of the obtained inorganic fine particles. The invention includes a dental composition including the inorganic filler.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a composition using an organic polymer material as a resin matrix, particularly an inorganic filler suitable for use as a filler in a dental composition, and a method for producing the same.

[0002]

2. Description of the Related Art The following properties are required of composite restorations which are frequently used in the dental field in recent years. Mechanical strength that can withstand high occlusal pressure during mastication, durability under severe conditions, coefficient of thermal expansion similar to tooth, low polymerization shrinkage to prevent peeling from tooth during polymerization hardening, etc. Mechanical properties, color and transparency compatible with natural teeth, optical properties such as surface lubricity and glossiness observed during polishing, and biocompatibility such as non-toxicity, non-solubility and low water absorption. No. In recent years, in particular, there has been a demand for a sustained release of fluorine, which enhances the tooth quality and suppresses secondary caries, and an X-ray contrast property, which can confirm the recurrence of dental caries after treatment and can be distinguished from enamel of the tooth. ing.

[0003] Conventionally, it is composed of a polymerizable monomer, a polymerization initiator and a filler such as an inorganic substance, an organic substance or an organic-inorganic composite compound, which are polymerizable for restoration, prosthesis, artificial tooth root, and other uses of a tooth defect. Composite restorations are used. Among these components, there have been many reports on fillers. This is because it is considered that the characteristics of the filler affect the characteristics of the composite restoration material since the proportion of the filler in the composite restoration material is large.

[0004] The filler used in the initial composite restoration material is α-quartz or various glasses having an average particle size of several μm to several hundred μm. It was mainstream. When these fillers are used, various properties such as moderate viscosity and operability, mechanical strength, low polymerization shrinkage, and thermal expansion coefficient close to that of teeth can be imparted to the composite restoration material. However, due to the large average particle size,
Polishing properties are not good, and there are drawbacks such as poor surface smoothness and surface gloss after polishing. In order to solve this problem, attempts have been made to make the average particle size as small as possible, but it is still insufficient. In order to overcome this drawback, ultrafine particles having an average particle diameter of 0.01 to 0.1 μm synthesized by a pyrolysis method or a gas phase reaction method, for example, spray pyrolysis silica or fumed silica were used as a filler. Composite restorations have been proposed and have been widely used under the general abbreviation MFR. This composite restoration material has good abrasiveness and excellent surface smoothness and surface gloss. However, when these ultrafine particles are dispersed in a polymerizable monomer,
Due to the large specific surface area, the consistency of the paste obtained is very high, so that the filling must be kept very low. For this reason, the mechanical properties of the composite restoration material, particularly the bending strength, are inferior. In addition, there are also problems such as a relatively large polymerization shrinkage when the paste is cured, and a very large thermal expansion coefficient of the cured product.
Sols starting from organometallic compounds as other fillers
Examples thereof include silica or silica composite oxides having a narrow particle size distribution, a spherical shape, and an average particle size of 0.1 μm to several μm synthesized from a solution reaction such as a gel method. These fillers are disclosed in JP-A-59-101409 and the like. Since this filler causes coagulation in the drying step, the surface treatment of the filler cannot be performed uniformly, and there is a problem in mechanical strength and durability such as material deterioration due to water absorption.

Recently, several fillers have been proposed that focus on optical properties such as abrasiveness and surface slipperiness.
For example, there are those commonly referred to as organic-inorganic composite fillers or composite fillers. These are obtained by mixing inorganic particles in advance with a polymerizable monomer, polymerizing once, and then pulverizing the polymer to obtain a composite filler. These fillers are disclosed in JP-A-54-107187, Japanese Patent Publication No. 3-1204.
No. 3 and JP-A-8-143747. Although these fillers have excellent optical properties such as surface lubrication and gloss after finish polishing, the effect of surface treatment is insufficient due to the presence of many organic components on the filler surface, and polymerizability The wettability with the monomer deteriorated, and there was a serious problem in mechanical properties. In addition, a hybrid composite restoration material combining ultrafine silica particles and a relatively large inorganic filler material has been proposed based on the idea of giving each filler an advantage. For example, JP-A-57-82303 and JP-T-57-50015
No. 0, JP-A-61-148109 and the like. However, although these hybrid types can sufficiently improve the mechanical properties, there are problems such as the paste being sticky and the operability being poor, and the smoothness after finish polishing being insufficient compared with the MFR. Therefore, in order to satisfy various properties required for the composite restoration material, many attempts have been made to fill the particles at a high density by a technique of finer and agglomerated particles or a surface treatment technique. For example, JP-A-7-196428 discloses a method of obtaining an aggregate from a solution state of a metal compound and silica sol for the purpose of improving the polishing property, and JP-A-7-196431 discloses an average particle diameter of 0.05 μm or more. A method for aggregating metal oxides of 1 μm or less is described. Although the polishing properties are improved, a surface treatment agent such as a silane coupling agent does not act on the agglomerated portion, and the durability is reduced due to water absorption.

According to the results of the study by the present inventors, in order to obtain sufficient mechanical properties such as sufficient abrasiveness, durability and mechanical strength, selection of a material for an inorganic filler, formation of fine particles and surface treatment. Is an important factor, but has been found to cause various problems. As a conventional method of forming fine particles, there is a dry pulverization method using a mechanical method such as a vibration mill, a ball mill, and a jet mill. In this method, it is difficult to obtain particles having an average particle diameter of 3 μm or less, and complicated steps such as classification are required due to the wide particle size distribution. In addition, in wet pulverization using such equipment, pulverization is possible up to an average particle diameter of 1 μm or less,
Agglomeration of the particles occurs during the drying process. Even if this aggregate was crushed using an appropriate crusher, it was impossible to crush it into primary particles. As another method of micronization,
Although there is production of fine particles from a solution state using a sol-gel method, an agglomerate is generated also in this method since a drying step is required. It has also been found that these aggregates cannot be uniformly subjected to surface treatment, and thus have a problem in durability when used in a composite restoration material as a filler. Conventionally, silica has been mainly used as a material of the inorganic filler, but has a high hardness, and has problems such as abrasiveness and abrasion of opposing teeth. Therefore, the materials have been diversified due to the necessity of imparting many properties to the inorganic filler. However, on the other hand, it was also found that the effect of the silane coupling agent, which is a commonly used surface treatment agent, was poor, and had an effect on mechanical strength and the like. In addition, although the polishing property and the surface lubricity can be improved by making the particles fine, it is considered that high filling in the composite restoration material becomes difficult due to the increase in the specific surface area, which may affect the mechanical strength. From the above, in order to satisfy the required characteristics of the composite restoration material, it is important to control the particle size and to ensure uniform monodispersion without agglomerates, and the surface needs to be uniformly treated with a surface treatment agent or the like. There is.

Generally, in the dental field, a silane coupling agent is known as a known surface treatment agent. However, this treating agent does not effectively act on any of the inorganic fillers, and is effective for inorganic fillers having a large number of OH groups on the surface such as silica. The effect decreases as the amount of is reduced. In Japanese Patent Publication No. 5-67656, a polymerizable aromatic carboxylic acid compound is used for surface treatment of alumina.
No. 5479 describes a dicarboxylic acid compound as a surface treating agent for an inorganic filler, and Japanese Patent No. 2925155 describes an organic phosphorus compound as a surface treating agent for an inorganic filler. As described above, since the amount of OH groups on the surface varies depending on the type of inorganic filler used, various surface treatment agents have to be used depending on the type of inorganic filler to be treated. Therefore, depending on the type of the surface treatment agent used for the surface treatment, the wettability with the resin is different, and not only the properties of the obtained composite restoration material but also the properties or the operability of the paste before curing are changed, and various properties are obtained. There is a risk of adverse effects. Further, Japanese Patent Publication No. 6-99136 describes a long-chain and short-chain silane coupling agent, and Japanese Patent Publication No. 2690364 describes a surface treatment using a silane coupling agent having a large hydrophobic group. All are aimed at increasing the surface treatment efficiency. However, there has been no inorganic filler having sufficient abrasion and durability and no agglomerates satisfying other properties, and a monodispersed and uniformly surface-treated inorganic filler has not been obtained.

[0008]

An object of the present invention is to provide a filler which can be used in dental compositions used in the dental field, such as crown materials, filling materials, prosthetic materials, adhesive materials and the like. In addition, while maintaining optical characteristics such as excellent abrasiveness and surface lubrication required especially as a filling material,
An object of the present invention is to provide a filler capable of imparting both mechanical strength, abrasion resistance and coloring resistance, and a method for producing the same.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, the average particle diameter was 0.01.
This problem has been solved by providing an inorganic filler in which the surface of inorganic fine particles of about 5 μm is coated with a polyorganosiloxane. That is, the present inventors provide the following inventions in the present application. In the present invention, the surface of inorganic fine particles having an average particle diameter of 0.01 to 5 μm is coated with a polyorganosiloxane, and the polyorganosiloxane has the general formula (I):

Embedded image (Where Z is RO— or OCN—, X is halogen, Y is OH—, R is an organic group having 8 or less carbon atoms, n, m, and L
Is an integer of 0 to 4 and n + m + L = 4) and a low condensate of the silane compound and a general formula (II):

Embedded image (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH—, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group, p is an integer of 1 to 3, a, b, and c are all 0 to
An integer of 3 and a + b + c + p = 4) an inorganic filler which is a co-condensate hydrolyzed or partially hydrolyzed in the presence of an organosilane compound and / or a low-condensate of the organosilane compound I will provide a.
Further, the polyorganosiloxane is a silane compound represented by the general formula (I) and / or a low condensate of the silane compound and an organosilane compound represented by the general formula (II) and / or a low condensate of the organosilane compound. And an inorganic filler which is a cocondensate hydrolyzed or partially hydrolyzed in the presence of a metal compound. In the present invention, (1) the raw material inorganic particles have an average particle diameter of 0.01 to 5 μm.
A wet pulverizing step of finely pulverizing the inorganic fine particles into inorganic fine particles, or a wet dispersing step of pulverizing the aggregated inorganic fine particles into primary particles, wherein the primary particles have an average particle diameter of 0.01 to 5 μm, and (2) obtained. Forming a polyorganosiloxane film on the surface of the inorganic fine particles. More specifically, in the present invention, the step of forming a polyorganosiloxane film,
(2-1) In the presence of the inorganic fine particles dispersed in an aqueous medium, a compound represented by the general formula (I):

Embedded image (Where Z is RO— or OCN—, X is halogen, Y is OH—, R is an organic group having 8 or less carbon atoms, n, m, and L
Is an integer of 0 to 4 and n + m + L = 4) and a low condensate of the silane compound and a general formula (II):

Embedded image (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH—, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group, p is an integer of 1 to 3, a, b, and c are all 0 to
An integer of 3 and a + b + c + p = 4) is hydrolyzed or partially hydrolyzed in the presence of an organosilane compound and / or a low condensate of the organosilane compound, and then the obtained silanol compound Or a silane compound represented by the general formula (I) and / or a low-condensate of the silane compound and the general formula (I)
Hydrolyzing or partially hydrolyzing the organosilane compound and / or a low-condensate of the organosilane compound represented by I) in the presence of a metal compound, and then co-condensing the obtained silanol compound, (2) -2) a step of heat-treating the obtained aqueous dispersion, and (2-3) a step of pulverizing the heat-treated solidified product to an average particle size of 0.01 to 5 µm. A manufacturing method is provided. Further, the present invention provides a dental composition comprising (a) the above-mentioned inorganic filler, (b) a polymerizable monomer, and (c) a polymerization initiator.

[0010] The present invention has the following effects: By forming a polyorganosiloxane film on the surface of inorganic fine particles that have been made finer by a finer or dispersing technique, 0.01 can be obtained without secondary aggregation. The inorganic filler can be obtained in the state of fine particles of up to 5 μm. The resulting fine and uniform inorganic filler can be dispersed in the dental composition in the form of primary particles without secondary aggregation, such as excellent abrasive properties and surface lubricity, which are characteristics of the fine particle filler. Optical properties are retained. Further, this polyorganosiloxane film only modifies the surface of the inorganic fine particles, and the characteristics inherent to the inorganic fine particles are maintained. Since the inorganic filler is coated with the polyorganosiloxane, the conventionally used organosilane compound such as a silane coupling agent can effectively act regardless of the type of the inorganic fine particles, and wets with the resin matrix. Properties can be further improved. Such inorganic fillers are more evenly dispersed in the dental composition,
In addition to the effect of forming the polyorganosiloxane film, the mechanical strength and abrasion resistance of the composition can be improved despite the fact that the composition is a fine particle filler.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The inorganic filler of the present invention is an inorganic fine particle having an average particle size of 0.01 to 5 μm, and the surface of which is coated with a polyorganosiloxane. As described above, since the average particle diameter is small and the monodisperse fine particles having a narrow particle size distribution, the dental composition containing the inorganic filler of the present invention has excellent gloss on the polished surface when polished after curing. It has surface lubricity that can be expressed. When such a fine particle filler is contained, the inorganic filler of the present invention is uniformly dispersed without agglomeration in the composition, although the abrasion resistance and durability are poor due to poor dispersibility. In addition, it has excellent abrasion resistance and durability in combination with the effect of forming the polyorganosiloxane film.

The average particle size used in the present invention is 0.01.
The inorganic fine particles having a size of from 5 μm to 5 μm are not particularly limited. For example, quartz, amorphous silica, aluminum silicate, aluminum oxide, titanium oxide, zirconium oxide, various glasses (glass by a melting method, synthetic glass by a sol-gel method, gas phase reaction) Calcium carbonate, talc, kaolin, clay, mica, aluminum sulfate, calcium sulfate, barium sulfate, calcium phosphate, hydroxyapatite, silicon nitride, aluminum nitride, titanium nitride, silicon carbide, boron carbide, water Examples include calcium oxide, strontium hydroxide, and zeolite. Preferred are glasses such as aluminosilicate glass, borosilicate, aluminoborate, and boroaluminosilicate glass containing a heavy metal such as strontium, barium, and lanthanum and / or fluorine. However, the average particle diameter used in the present invention is 0.01 to 5 μm.
Since the inorganic fine particles of m are obtained by a wet pulverizing step or a wet dispersing step in an aqueous medium, water-soluble inorganic fine particles such as sodium fluoride, calcium fluoride, and metal fluorides such as strontium fluoride are not preferred. .

The inorganic fine particles having an average particle diameter of 0.01 to 5 μm can be obtained by wet-pulverizing commercially available raw inorganic particles usually used as a filler or the like. The wet milling does not require a special method, and can be performed by using a method generally used in the art.
For example, the raw inorganic particles may be refined in the presence of an aqueous medium using a container driving medium mill such as a ball mill or a vibration mill, or a pulverizing medium stirring mill such as an attritor, a sand grinder, an aniler mill, or a tower mill. As the aqueous medium, water alone or one obtained by substituting a part or all of water with an aqueous solvent such as an alcohol, a ketone such as acetone, or an ether as necessary may be used. When these aqueous solvents are used, the cohesive force of the solidified product after the heat treatment is weakened, so that it can be easily crushed. The wet pulverization conditions vary depending on the size and hardness of the raw material inorganic particles, the amount charged, the amount of the aqueous solvent added, or the type of the pulverizer, but also include the pulverization conditions depending on the average particle size of the required inorganic fine particles, as appropriate. You can choose. Another method for producing inorganic fine particles having an average particle diameter of 0.01 to 5 μm can be obtained by wet-dispersing an inorganic fine particle aggregate having primary particles of 0.01 to 5 μm in the presence of an aqueous medium. The wet dispersion does not require a special method, and can be performed by a method generally used in the art. For example, the aggregated inorganic fine particles may be dispersed in the presence of an aqueous medium using a wet disperser such as a dissolver or a homogenizer. Dispersion conditions are the size and hardness of the aggregated inorganic fine particles, the charged amount,
Although it depends on the amount of the aqueous solvent added, the type of the pulverizer, and the like, the dispersion conditions such as the dispersion time, the stirrer, and the rotation speed can be appropriately selected according to the required average particle size of the inorganic fine particles.

The resulting inorganic fine particles form a polyorganosiloxane film on the surface thereof as follows. When pulverized or dispersed to a desired average particle diameter, the resulting aqueous dispersion containing the inorganic fine particles has the general formula (I):

Embedded image (Where Z is RO— or OCN—, X is halogen, Y is OH—, R is an organic group having 8 or less carbon atoms, n, m, and L
Is an integer of 0 to 4 and n + m + L = 4) and a low condensate of the silane compound and a general condensate (II):

Embedded image (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH—, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group, p is an integer of 1 to 3, a, b, and c are each an integer of 0 to 3, and a + b + c + p = 4) and co-exist with an organosilane compound and / or a low-condensation product of the organosilane compound, hydrolyze or partially hydrolyze in this system, co-condensate via a silanol compound, and form a film. . Alternatively, a silane compound represented by the general formula (I) and / or a low condensate of the silane compound and an organosilane compound represented by the general formula (II) and / or a low condensate of the organosilane compound coexist with a metal compound. It hydrolyzes or partially hydrolyzes under a silanol compound and co-condenses to form a film. As a result, the system is in a state in which inorganic fine particles having an average particle diameter of 0.01 to 5 μm are finely dispersed without association in an aqueous dispersion in which the condensed organosilane compound, that is, the polyorganosiloxane is dispersed. The form of the compound added to the aqueous dispersion in the formation of the polyorganosiloxane film is not particularly limited, and may be a monomer or a low (co) condensate obtained by partially hydrolyzing and low (co) condensing the monomer ( Oligomers) and mixtures thereof.
There is no particular limitation on the method of addition into the aqueous dispersion,
The compounds to be added can be added separately or in advance, and can be added all at once or intermittently. However, in order to enhance the uniformity of the addition, a method of diluting the compound to be added with an organic solvent compatible with the aqueous dispersion and adding the compound intermittently is preferable. When a low co-condensate (oligomer) is used for forming the polyorganosiloxane film, the shape is not particularly limited, but a linear shape is preferable to a three-dimensional shape. In addition, if the degree of polymerization is too large, the cocondensation reactivity on the surface of the inorganic fine particles is poor,
The formation state of the polyorganosiloxane film may be deteriorated. Further, as another method for forming the polyorganosiloxane film, a solution containing the precursor of the above-mentioned polyorganosiloxane film is prepared in advance, and the obtained aqueous dispersion containing the inorganic fine particles is mixed with the solution, and the solution is uniformly mixed. There is no limitation on the method of forming a film in a state where the film is dispersed.

Z in the general formulas (I) and (II)
Is an RO group capable of forming a silanol group by hydrolysis, R
¹ O group or OCN group, X represents halogen, Y represents OH group. R and R ¹ are organic groups having 8 or less carbon atoms, and specific examples include methyl, ethyl, 2-chloroethyl, allyl, aminoethyl, propyl, isopentyl,
Examples include an alkyl group or an alkyl derivative group such as hexyl, 2-methoxyethyl, phenyl, m-nitrophenyl, and 2,4-dichlorophenyl. From the viewpoint of hydrolysis rate and discoloration due to carbon residue in the polyorganosiloxane film, methyl and ethyl are preferred. The halogen includes chlorine and bromine, and is preferably chlorine. R ² in the general formula (II) is not particularly limited as long as it is an organic group, but those having a short main chain of the organic group are preferable in that the structural strength of the polyorganosiloxane film can be maintained. Specific examples of the silane compound represented by the general formula (I) include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraallyloxysilane, tetrabutoxysilane, tetrakis (2-
Ethylhexyloxy) silane, trimethoxychlorosilane, triethoxychlorosilane, triisopropoxychlorosilane, trimethoxyhydroxysilane, diethoxydichlorosilane, tetraphenoxysilane, tetrachlorosilane, silicon hydroxide (silicon oxide hydrate), tetraisocyanate silane And ethoxysilane triisocyanate. Among these, tetramethoxysilane or tetraethoxysilane is more preferred. Further, a low-condensation product of the silane compound represented by the general formula (I) is more preferable, and specifically, a low-condensation silane compound obtained by partially hydrolyzing and condensing tetramethoxysilane or tetraethoxysilane. . These silane compounds can be used alone or in combination of two or more. Specific examples of the organosilane compound represented by the general formula (II) include methyltrimethoxysilane, ethyltrimethoxysilane, methoxytripropylsilane, propyltriethoxysilane, hexyltrimethoxysilane, vinyltrimethoxysilane, and vinyl. Triethoxysilane, vinyltri (β-methoxyethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, 3-aminopropyltriethoxysilane, methyltrichlorosilane, phenyltrichlorosilane, trimethylsilyl isocyanate, vinylsilyltriisocyanate, phenylsilyltriisocyanate and the like. In addition, low condensates of these organosilane compounds can also be used.
Among these organosilane compounds, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, vinyl (β-methoxyethoxy) silane,
γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-
Mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane and the like are preferred, and γ-methacryloyloxypropyltrimethoxysilane is more preferred. These organosilane compounds can be used alone or
More than one species can be used in combination.

As the metal compound, a metal compound which is hydrolyzed or partially hydrolyzed and condensed to form a skeleton of a polyorganosiloxane film, or in the presence of another compound which forms a skeleton of a polyorganosiloxane film, is used. Any of those which modify and contribute to the skeleton can be used without particular limitation. Specific examples of such metal compounds include metal halides, metal nitrates, metal sulfates, metal ammonium salts, organometallic compounds, alkoxymetal compounds, and derivatives of these metal compounds. The metal compounds can be used alone or in combination of two or more. Examples of the metal element constituting these metal compounds include elements of Groups I to V of the periodic table. Also, among these metal compounds, it is possible to form a three-dimensional skeleton by hydrolysis and condensation alone.
Metal compounds composed of Group I to Group V metal elements are preferred. More preferably, it is a metal compound composed of Zr or Ti. When the inorganic filler of the present invention in which a polyorganosiloxane is formed by coexisting a metal compound composed of these two kinds of metal elements is used as a filler for a dental composition, the composition is supplemented with X-rays. Contrast properties can be imparted. Specific examples of the metal compound composed of Zr or Ti include titanium tetrachloride, titanyl sulfate,
Methyltrichlorotitanium, dimethyldichlorotitanium, tetramethoxytitanium, tetraethoxytitanium, tetraisopropoxytetane, tetraisobutoxytitanium, tetra (2-ethylhexyloxy) titanium, diethoxydibutoxytitanium, isopropoxytitanium trioctarate, Examples include isopropoxytitanium diacrylate, tributoxytitanium stearate, zirconium tetrachloride, zirconium oxychloride, zirconium acetate, zirconium lactate, tetramethoxyzirconium, tetraethoxyzirconium, tetraisopropoxyzirconium, tetrabutoxyzirconium and the like. In addition, derivatives of the above metal compounds can also be used. As the derivative of the metal compound, for example, halogen, N
A part of a hydrolyzing group such as O ₃ , SO ₄ , an alkoxy group, an acyloxy group is converted to a dicarboxylic acid group, an oxycarboxylic acid group,
Diketone group, β-ketoester group, β-diester group,
A metal compound substituted with a group capable of forming a chelate compound such as an alkanolamine group is exemplified. In addition, a low-condensation metal compound (oligomer or polymer) obtained by partially hydrolyzing and low-condensing a metal compound can also be used.

The hydrolysis or partial hydrolysis of the compound added to the aqueous dispersion is carried out under a relatively low speed stirring condition. The stirring temperature is in the range of 10 ° C. to 100 ° C., and more preferably in the range of 25 ° C. to 50 ° C. There is no limitation as long as the temperature is lower than the boiling point of the aqueous medium. The stirring time is usually in the range of several minutes to several tens of hours, more preferably in the range of 30 minutes to 4 hours, and the type and amount of the compound to be added, the type of inorganic fine particles, the average particle size and the proportion of the aqueous dispersion, It can be adjusted by the type of the aqueous medium and the proportion of the aqueous medium in the aqueous dispersion. Stirring does not require a special method, and can be carried out by using equipment commonly used in the art. For example, stirring may be performed using a stirrer capable of stirring a slurry-like material such as a universal mixing stirrer or a planetary mixer. For the purpose of accelerating the rate of hydrolysis or partial hydrolysis and co-condensation, addition of a sol-gel catalyst such as an acid and an alkali, an organometallic compound, a metal alkoxide, or a metal chelate compound is a preferred embodiment. Specific catalysts include:
For example, hydrochloric acid, acetic acid, nitric acid, formic acid, sulfuric acid, inorganic acids such as phosphoric acid, p-toluenesulfonic acid, benzoic acid, phthalic acid,
Examples thereof include organic acids such as maleic acid, and alkali catalysts such as potassium hydroxide, sodium hydroxide, and ammonia. As the aqueous solvent used in the step of forming the polyorganosiloxane film, any water and / or organic solvent that is compatible with water can be used without any limitation. Particularly preferably, it can be appropriately selected from alcohols, ketones and ethers. These solvents not only improve the compatibility of various compounds used in the polyorganosiloxane forming step, but also reduce the cohesiveness of the particles in the heat treatment step and have a great effect of further improving the crushability. Specific examples of these solvents include alcohols such as ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, t-butyl alcohol and isobutyl alcohol, ethers such as tetrahydrofuran and dioxane, and ketones such as acetone. Is mentioned. These solvents can be used alone or
More than one species may be used. Preferably, ethyl alcohol, n-propyl alcohol, and isopropyl alcohol are suitably used.

The addition amount of the silane compound and the organosilane compound is not particularly limited, and can be appropriately selected depending on the method of forming the film, the type of the inorganic fine particles, the average particle diameter, and the like. ₂ conversion amount (total amount of silane compound and organosilane compound)
In the range of 0.1 to 20 parts by weight. Preferably 0.1 to
It is in the range of 10 parts by weight, more preferably in the range of 0.1 to 5 parts by weight. Further, the coexistence ratio of the silane compound and the organosilane compound in the polyorganosiloxane film is 99: 1 to 20:80, preferably 99: 1 to 30:70, and more preferably 99: 1 by weight in terms of SiO _2.
1 to 40:60. When a polyorganosiloxane film is formed in the coexistence of a metal compound, all SiO
Metal oxides in terms of the metal compound to a ₂ equivalent amount 100 parts by weight can refer coexist in the range of 0.1 to 500 parts by weight, more preferably from 0.1 to 200 parts by weight.

Next, the system in such a state is subjected to a heat treatment to remove and solidify the aqueous medium. The heat treatment consists of two stages, maturation and baking, the former aiming at growth of the polyorganosiloxane film and removal of the aqueous medium, and the latter aiming at structural strengthening. In the former case, it is necessary to perform the former in a stationary state because the film structure is not distorted and the aqueous medium is removed, and equipment such as a box-type hot air dryer is preferable. The aging temperature is in the range of room temperature to 100 ° C, more preferably 40 to 80 ° C. When the temperature is lower than this range, the removal of the aqueous medium is insufficient, and when the temperature is higher than this range, there is a possibility that the polyorganosiloxane film may be defective or may be peeled off from the surface of the inorganic fine particles. is there. The aging time depends on the capacity of the dryer and the like, and there is no limitation as long as the aqueous medium can be sufficiently removed. On the other hand, the firing step is divided into temperature raising and mooring. In the former case, it is better to gradually raise the temperature to the target temperature over a long period of time, and a rapid temperature increase is not preferable because distortion occurs in the polyorganosiloxane film. The latter is firing at a constant temperature, and the time is 10 hours to 10 hours.
0 hours, more preferably 10 hours to 50 hours. The firing temperature is in the range of 100 to 350C, more preferably 100 to 200C. This temperature must be appropriately selected so as not to affect the material of the inorganic fine particles and not to render the porous polyorganosiloxane film nonporous. As described above, the aqueous medium is removed by the heat treatment, and a contracted solid is obtained. Although the solidified product is in an aggregated state of inorganic fine particles, it is not a mere aggregate of inorganic fine particles, and a polyorganosiloxane film formed by co-condensation is interposed at the interface between individual fine particles. Therefore,
In the next step, when the solidified product is crushed into inorganic fine particles equivalent to those before the formation of the polyorganosiloxane film, individual inorganic fine particles whose surface is coated with the polyorganosiloxane,
That is, the inorganic filler of the present invention is obtained. Here, "disintegrate into inorganic fine particles before forming the polyorganosiloxane film" means to disintegrate into inorganic fine particles, and the difference from the original inorganic fine particles is that individual inorganic fine particles are coated with polyorganosiloxane. That is being done. However, secondary aggregates may be included as long as there is no problem. Crushing of the solidified material can be easily performed by applying a shearing force or an impact force, and the crushing method can be performed using, for example, a Henschel mixer, a cross rotary mixer, a super mixer, or the like.

The thus obtained inorganic filler of the present invention has an average particle diameter of 0.01 to 5 μm, and its surface is coated with a polyorganosiloxane. The average particle size and particle size distribution of the inorganic filler having a surface coated with polyorganosiloxane can be confirmed by a laser diffraction type particle size analyzer. As a result, the inorganic filler of the present invention is powdered in a uniformly dispersed state because the average particle diameter and the monodisperse particle size distribution in the state where the inorganic fine particles are uniformly dispersed in the aqueous dispersion are the same. Is admitted. On the other hand, the average particle diameter of the inorganic fine particles not coated with the polyorganosiloxane was shifted to the larger side, and showed a polydisperse particle size distribution due to the presence of aggregates.
The state of dispersion can be confirmed by observation with an electron microscope. In addition, the surface area of the inorganic filler of the present invention can be measured by the BET method, and it is recognized that the specific surface area of the inorganic filler is increased by the formation of the polyorganosiloxane film. In addition, despite the presence of many OH groups on the film surface, the fluidity or dispersibility of the filler is good because the contact between the fine particles is point contact due to the unevenness of the film surface. Conceivable.
The thickness of the polyorganosiloxane film also affects the amount of the silane compound and the organosilane compound added.
It is 0 nm or less, more preferably 100 nm or less. Also, when this inorganic filler is used in a dental composition, a resin component penetrates into irregularities on the surface of the polyorganosiloxane film,
It was recognized that the mechanical effect was improved by the fitting effect. At the same time, it was confirmed that the polishing property was also improved.
In addition, in order to highly fill the inorganic filler, a general formula (II):

Embedded image (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH-, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group having 6 or less carbon atoms, p is an integer of 1 or 2, and a, b and c are each an integer of 0 to 3. A, b + c + p
= 4). It is effective to further treat the polyorganosiloxane film with an organosilane compound represented by the following formula: As a result, high filling is possible, and various characteristics required as a dental composition can be satisfied.

Among the above organosilane compounds, silane coupling agents known in the dental field are effective, and specific examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltrichlorosilane, and vinyl (β-methoxysilane). Ethoxy) silane, γ-methacryloyloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane and the like. More preferred is γ-methacryloyloxypropyltrimethoxysilane. These organosilane compounds can be used alone or in combination of two or more. The reason that the affinity with the resin component is enhanced by these organosilane compounds is that the organosilane compound is efficiently and uniformly surface-treated by reacting with a large number of OH groups present on the polyorganosiloxane film. It is because.

Another embodiment of the present invention is a dental composition comprising the above-mentioned inorganic filler of the present invention. In particular, (a)
A dental composition comprising the inorganic filler of the present invention, (b) a polymerizable monomer, and (c) a polymerization initiator. In the composition, the inorganic filler of the present invention can be uniformly dispersed in a non-aggregated state due to the presence of the polyorganosiloxane film on the surface of the matrix containing the organic polymer material as a main component, and the organic filler and the organic matrix can be dispersed. The cured product of the composition is characterized by exhibiting excellent physical properties due to its high affinity. Furthermore, the cured product of the dental composition containing the inorganic filler of the present invention as a filler has excellent fineness after polishing due to the fineness of the filler. Despite being a fine filler, it has excellent wear resistance. This excellent wear resistance is due to the action of the polyorganosiloxane film present on the surface of the inorganic filler and the organosilane compound added when dispersed in the matrix.
It is considered that this is because the filler has an interaction with the matrix with a strong affinity, and the mating effect of the matrix penetrating the polyorganosiloxane film is brought about.

The polymerizable monomers that can be used in the dental composition together with the inorganic filler of the present invention include known monofunctional and polyfunctional polymerizable monomers generally used as dental compositions. It can be used from monomers. A typical example that is generally preferably used is a polymerizable monomer having an acryloyl group and / or a methacryloyl group. In the present invention, both the acryloyl group-containing polymerizable monomer and the methacryloyl group-containing polymerizable monomer are represented by (meth) acrylate or (meth) acryloyl. A specific example is as follows. Monofunctional monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate,
Hexyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, glycidyl (meth) acrylate,
Lauryl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, allyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, glycerol (meth) acrylate, isobonyl (meth) ) Acrylate compounds such as acrylates, silane compounds such as γ- (meth) acryloyloxypropyltrimethoxysilane, γ- (meth) acryloyloxypropyltriethoxysilane, 2- (N, N-dimethylamino) ) Ethyl (meth) acrylate, N-methylol (meth) acrylamide,
Nitrogen-containing compounds such as diacetone (meth) acrylamide, aromatic bifunctional monomer: 2,2-bis (4- (meth)
Acryloyloxyphenyl) propane, 2,2-bis (4- (3- (meth) acryloyloxy-2-hydroxypropoxy) phenyl) propane, 2,2-bis (4- (meth) acryloyloxyethoxyphenyl)
Propane, 2,2-bis (4- (meth) acryloyloxydiethoxyphenyl) propane, 2,2-bis (4
-(Meth) acryloyloxytetraethoxyphenyl) propane, 2,2-bis (4- (meth) acryloyloxypentaethoxyphenyl) propane, 2,2-
Bis (4- (meth) acryloyloxydipropoxyphenyl) propane, 2 (4- (meth) acryloyloxyethoxyphenyl) -2 (4- (meth) acryloyloxydiethoxyphenyl) propane, 2 (4- (meth) Acryloyloxydiethoxyphenyl) -2 (4
-(Meth) acryloyloxytriethoxyphenyl)
Propane, 2 (4- (meth) acryloyloxydipropoxyphenyl) -2 (4- (meth) acryloyloxytriethoxyphenyl) propane, 2,2-bis (4
-(Meth) acryloyloxydipropoxyphenyl)
Aliphatic difunctional monomers such as propane and 2,2-bis (4- (meth) acryloyloxyisopropoxyphenyl) propane: 2-hydroxy-3-acryloyloxypropyl methacrylate, neopentyl glycol dihydroxypivalate (Meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, neopentyl glycol di ( (Meth) acrylate, propylene glycol di (meth) acrylate, 1,3-butanediol di (meth)
Acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, glycerin di (meth) acrylate, etc. Trifunctional monomer: trimethylolpropane tri (meth)
Acrylate, trimethylolethane tri (meth) acrylate, trimethylol methane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, etc. Tetrafunctional monomer: pentaerythritol tetra (meth)
Acrylate, ditrimethylolpropanetetra (meth) acrylate and the like can be mentioned. Specific examples of the urethane-based polymerizable monomer include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Hydroxypropyl (meth) acrylate; a polymerizable monomer having a hydroxyl group such as 3-chloro-2-hydroxypropyl (meth) acrylate, methylcyclohexane diisocyanate, methylenebis (4-cyclohexyl isocyanate), hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate And di (meth) acrylates having a bifunctional or trifunctional or higher urethane bond derived from an adduct with a diisocyanate compound such as isophorone diisocyanate, diisocyanate methylmethylbenzene, and 4,4-diphenylmethane diisocyanate. . In addition to the (meth) acrylate-based polymerizable monomer, other polymerizable monomers depending on the purpose of the dental composition, for example, a monomer, oligomer or oligomer having at least one polymerizable group in the molecule. There is no limitation even if a polymer is used. In addition, there is no problem even if a substituent such as an acidic group or a fluoro group is present in the same molecule. In the present invention, the polymerizable monomer includes not only a single component but also a mixture of a plurality of polymerizable monomers. When the viscosity of the polymerizable monomer is extremely high at room temperature or when the polymerizable monomer is a solid, it is preferable to use the polymerizable monomer in combination with a polymerizable monomer having a low viscosity. This combination is not limited to two types, and may be three or more types. Further, since a polymer composed of only a monofunctional polymerizable monomer does not have a crosslinked structure, the mechanical strength of the polymer generally tends to be inferior. for that reason,
When a polymerizable monomer is used, it is preferably used together with a polyfunctional polymerizable monomer. The most preferred combination of polymerizable monomers is a method in which an aromatic compound of a bifunctional polymerizable monomer is used as a main component and an aliphatic compound of a bifunctional polymerizable monomer is used. Specifically, 2,2-bis (4- (3-methacryloyloxy-2-hydroxypropoxy) phenyl) propane (Bis-GMA) and triethylene glycol dimethacrylate (TEGDM)
A). When imparting tooth or base metal adhesion to the dental composition containing the inorganic filler of the present invention,
It is effective to use, as a part or all of the polymerizable monomer, a polymerizable monomer containing an acid group such as a phosphoric acid group, a carboxylic acid group, or a sulfonic acid group in a molecule. In order to improve the noble metal adhesion, it is also effective for the present invention to use a polymerizable monomer containing a sulfur atom in the molecule.
Specific examples of these polymerizable monomers having an adhesive ability are as follows. Carboxylic acid group-containing polymerizable monomer: (meth) acrylic acid,
1,4-di (meth) acryloyloxyethyl pyromellitic acid, 6- (meth) acryloyloxynaphthalene-
1,2,6-tricarboxylic acid, N- (meth) acryloyl-p-aminobenzoic acid, N- (meth) acryloyl-5
-Aminosalicylic acid, 4- (meth) acryloyloxyethyl trimellitic acid and its anhydride, 4- (meth)
Acryloyloxybutyl trimellitic acid and its anhydride, 2- (meth) acryloyloxybenzoic acid, β-
(Meth) acryloyloxyethyl hydrogen succinate, β- (meth) acryloyloxyethyl hydrogen maleate, 11- (meth) acryloyloxy-1,1-undecanedicarboxylic acid, p-vinylbenzoic acid and the like. Phosphoric acid group-containing monomer: 2- (meth) acryloyloxyethyl dihydrogen phosphate, 3- (meth)
Acryloyloxypropyl dihydrogen phosphate, 10- (meth) acryloyloxydecyl dihydrogen phosphate, bis (2- (meth) acryloyloxyethyl) hydrogen phosphate, 2- (meth) acryloyloxyethyl phenyl hydrogen Phosphate and the like. Sulfonic acid group-containing monomer: 2- (meth) acrylamide-2-methylpropanesulfonic acid, 4- (meth) acryloyloxybenzenesulfonic acid, 3- (meth) acryloyloxypropanesulfonic acid and the like. Polymerizable monomer containing a sulfur atom: (meth) acrylate having a triazine thiol group, (meth) acrylate having a mercapto group, (meth) acrylate having a polysulfide group, (meth) having a thiophosphate group
Examples include acrylate, (meth) acrylate having a disulfide cyclic group, (meth) acrylate having a mercaptodithiazole group, (meth) acrylate having a thiouracil group, and (meth) acrylate having a thiirane group. There is no problem even if these polymerizable monomers are used alone or in combination of two or more.

The polymerization initiator that can be used in the dental composition together with the inorganic filler of the present invention is not particularly limited, and a known radical generator can be used without any limitation.
Polymerization initiators are generally those that initiate polymerization by mixing immediately before use (chemical polymerization initiator), those that initiate polymerization by heating or heating (thermal polymerization initiators), those that initiate polymerization by light irradiation ( Photopolymerization initiator). Examples of the chemical polymerization initiator include a redox-type polymerization initiation system composed of an organic peroxide / amine compound or an organic peroxide / amine compound / sulfinate, an organic peroxide / amine compound / borate compound, and oxygen and water. Examples thereof include organometallic polymerization initiator systems which initiate polymerization by reacting. Further, sulfinic acid salts and borate compounds can be initiated by reaction with a polymerizable monomer having an acidic group. Specific examples of the organic peroxide include benzoyl peroxide, parachlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, acetyl peroxide, lauroyl peroxide, tertiary butyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane, 2,
5-dihydroperoxide, methyl ethyl ketone peroxide, tertiary butyl peroxybenzoate, and the like. The amine compound is preferably a secondary or tertiary amine in which an amine group is bonded to an aryl group, and specific examples include p-N, N'-dimethyl-toluidine, N, N'-dimethylaniline, '-
β-hydroxyethyl-aniline, N, N′-di (β-
Hydroxyethyl) -aniline, pN, N'-di (β
-Hydroxyethyl) -toluidine, N-methyl-aniline, p-N-methyl-toluidine and the like. Specific examples of the sulfinates include sodium benzenesulfinate, lithium benzenesulfinate, and sodium p-toluenesulfinate. Examples of the borate compound include trialkylphenylboron, trialkyl (p-fluorophenyl) boron (the alkyl group is an n-butyl group, an n-octyl group,
-Dodecyl group, etc.) sodium salt, lithium salt, potassium salt, magnesium salt, tetrabutylammonium salt,
And tetramethylammonium salts. Also,
Examples of the organometallic polymerization initiator include organic boron compounds such as triphenylborane, tributylborane, and tributylborane partial oxide. As the thermal polymerization initiator by heating or heating, azo compounds such as azobisisobutyronitrile, methyl azobisisobutyrate and azobiscyanovaleric acid are preferably used in addition to the above-mentioned organic peroxides. On the other hand, examples of the photopolymerization initiator include those composed of a photosensitizer, and a photosensitizer / photopolymerization accelerator. Specific examples of the photosensitizer include benzyl, camphorquinone, α-naphthyl, acetonaphthene, p,
α such as p′-dimethoxybenzyl, p, p′-dichlorobenzylacetyl, pentanedione, 1,2-phenanthrenequinone, 1,4-phenanthrenequinone, 3,4-phenanthrenequinone, 9,10-phenanthrenequinone and naphthoquinone -Diketones, benzoin, benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether, thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2-isopropylthioxanthone, 2-methoxythioxanthone, 2-hydroxythioxanthone, 2,4 Thioxanthones such as diethylthioxanthone, 2,4-diisopropylthioxanthone, benzophenones such as benzophenone, p-chlorobenzophenone and p-methoxybenzophenone, 2,4,6- Acylphosphine oxides such as trimethylbenzoyldiphenylphosphine oxide and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide; 2-benzyl-dimethylamino-1- (4-morpholine); Α-aminoacetophenones such as (linophenyl) -butanone-1, 2-benzyl-diethylamino-1- (4-morpholinophenyl) -propanone-1, benzyldimethylketal, benzyldiethylketal, and benzyl (2-methoxyethylketal) ) And other ketals,
Bis (cyclopentadienyl) -bis [2,6-difluoro-3- (1-pyrrolyl) phenyl] -titanium, bis (cyclopentadienyl) -bis (pentanefluorophenyl) -titanium, bis (cyclopentadi And titanocenes such as (enyl) -bis (2,3,5,6-tetrafluoro-4-disiloxyphenyl) -titanium.
Specific examples of the photopolymerization accelerator include N, N-
Dimethylaniline, N, N-diethylaniline, N, N-
Di-n-butylaniline, N, N-dibenzylaniline, pN, N-dimethyl-toluidine, mN, N-dimethyl-toluidine, pN, N-diethyl-toluidine, p-bromo-N , N-dimethylaniline, m-chloro-N, N-dimethylaniline, p-dimethylaminobenzaldehyde, p-dimethylaminoacetophenone,
p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid amino ester,
N, N-dimethylanthranilic acid methyl ester, N, N-dihydroxyethylaniline, p-N, N
-Dihydroxyethyl-toluidine, p-dimethylaminophenyl alcohol, p-dimethylaminostyrene,
N, N-dimethyl-3,5-xylidine, 4-dimethylaminopyridine, N, N-dimethyl-α-naphthylamine, N, N-dimethyl-β-naphthylamine, tributylamine, tripropylamine, triethylamine, N
-Methyldiethanolamine, N-ethyldiethanolamine, N, N-dimethylhexylamine, N, N-dimethyldodecylamine, N, N-dimethylstearylamine, N, N-dimethylaminoethyl methacrylate, N,
N-diethylaminoethyl methacrylate, 2,2'-
Tertiary amines such as (n-butylimino) diethanol, secondary amines such as N-phenylglycine, barbituric acids such as 5-butylbarbituric acid and 1-benzyl-5-phenylbarbituric acid, dibutyltin Diacetate, dibutyltin dilaurate, dioctyltin dilaurate, dioctyltin diversate, dioctyltin bis (isooctyl mercaptoacetate)
Salts, tin compounds such as tetramethyl-1,3-diacetoxydistannoxane, aldehyde compounds such as lauryl aldehyde and terephthalaldehyde, dodecyl mercaptan, 2-mercaptobenzoxazole, 1-decanethiol, thiosalicylic acid and the like. And sulfur compounds. Further, in order to improve the photopolymerization accelerating ability, in addition to the photopolymerization accelerator, citric acid, malic acid, tartaric acid, glycolic acid, gluconic acid, α-oxyisobutyric acid, 2-hydroxypropanoic acid, 3-hydroxypropane Acid, 3-
The addition of oxycarboxylic acids such as hydroxybutanoic acid, 4-hydroxybutanoic acid and dimethylolpropionic acid is effective. These polymerization initiators can be used alone or in combination of two or more. Further, they can be used in combination regardless of the polymerization form or the type of polymerization initiator. The amount of the polymerization initiator to be added may be appropriately selected according to the intended use. Generally, 0.1 to the polymerizable monomer.
It may be selected from the range of 10 to 10 parts by weight. Among the polymerization initiators described above, it is a preferred embodiment to use a photopolymerization initiator that generates a radical by light irradiation, and is most preferable in that the dental composition can be polymerized in a state where air is little mixed. It is preferably used. Further, among the photopolymerization initiators, a combination of α-diketone and tertiary amine is more preferable, and an aromatic amine in which an amino group such as camphorquinone and ethyl pN, N-dimethylaminobenzoate is directly bonded to a benzene ring is preferable. Alternatively, a combination of an aliphatic amine having a double bond in a molecule such as N, N-dimethylaminoethyl methacrylate is most preferable. In addition, depending on the intended use, coumarin-based, cyanine-based, thiazine-based sensitizing dyes, halomethyl group-substituted -s-triazine derivative, diphenyliodonium salt compound or the like by irradiation of Brönsted acid or Lewis acid. The resulting photoacid generator, quaternary ammonium halides, transition metal compounds and the like can also be used as appropriate. As the dental composition, a second filler can be compounded in addition to the inorganic filler of the present invention. As the second filler, those known as dental fillers, for example, quartz, amorphous silica, clay aluminum oxide, talc, mica, kaolin, glass, barium sulfate, zirconium oxide, titanium oxide, silicon nitride, aluminum nitride, Inorganic substances such as titanium nitride, silicon carbide, boron carbide, calcium carbide, hydroxyapatite, and calcium phosphate; polymethyl methacrylate;
Organic substances such as polymers or oligomers such as polyethyl methacrylate, polyvinyl chloride, polystyrene, polyester, and nylon; and organic-inorganic composites can be preferably used. There is no problem even if the second filler is used alone or in combination of two or more. In addition, it is preferable to use the second filler which has been surface-treated with a conventionally known titanate coupling agent, aluminate coupling agent or silane coupling agent. The mixing ratio of the second filler can be appropriately selected as needed, and may be selected, for example, from a range of 1 to 90 parts by weight.
Further, in the dental composition, polymerization inhibition of an ultraviolet absorber such as 2-hydroxy-4-methylbenzophenone, hydroquinone, hydroquinone monomethyl ether, 2,5-di-tert-butyl-4-methylphenol and the like is prohibited. Components such as an agent, a discoloration inhibitor, an antibacterial material, a coloring pigment, and other conventionally known additives can be optionally added as necessary. The packaging form of the dental composition of the present invention is not particularly limited, and may be any of a one-pack packaging form and a two-pack packaging form, or other forms, depending on the type of polymerization initiator or purpose of use, It can be appropriately selected according to the application.

[0025]

EXAMPLES Hereinafter, the present invention will be described in more detail and specifically with reference to examples, but the present invention is not limited thereto. The performance evaluation method of the dental composition employed in the following examples is as follows. (1) Toothbrush abrasion test evaluation purpose: To evaluate the abrasion resistance of a dental composition specimen. Evaluation method: After filling the prepared dental composition into four stainless steel molds for a toothbrush abrasion test, placing a cover glass on both sides and pressing against a glass kneading plate, a photopolymerization irradiator (Griplight II: Light irradiation was performed for 30 seconds at each of six locations using Shofu Co., Ltd.) to cure. After curing, the cured product (15 × 15 × 2.6 mm and 25 × 1
A 5 × 2.6 mm rectangular mold was taken out and polished using sandpaper # 600 and # 1200 in order to adjust the thickness to 2.5 mm.
X2.5mm and 25x15x2.5mm rectangular mold)
And Next, the surface of the specimen was mirror-finished by buffing, and then the weight of the specimen was measured. Thereafter, the specimen was attached to a toothbrush abrasion tester, and a toothbrush (Perio H:
A toothbrush abrasion test was conducted using 20,000 cycles (about 3 hours) using a paste (Sunstar) and a paste (White: Sunstar). The amount of abrasion (wt%) is the weight loss of the specimen due to abrasion / the weight of the specimen before the test x 10
Calculated from 0. In addition, the test was performed with four test pieces and evaluated by the average value.

(2) Abrasiveness test evaluation purpose: To evaluate the surface lubricity of a dental composition specimen. Evaluation method: After filling the prepared dental composition into a stainless steel mold, placing a cover glass on both sides and pressing the glass with a glass plate, using a photopolymerization irradiator (Griplight II: manufactured by Matsukaze Co., Ltd.) Light irradiation (one side: 30 seconds) was performed from both sides to cure. After curing, the cured product was taken out of the mold and used as a test specimen (4φ × 6 mm: cylindrical type). The test body was polished in order using a silicon point (manufactured by Matsukaze) and One Gloss Super Buff (manufactured by Matsukaze), and the condition of the polished surface was visually evaluated. The test was performed on one specimen.
The evaluation was performed with 0 pieces, and a comprehensive evaluation was performed.

(3) Color resistance test evaluation purpose: To evaluate the color resistance of the dental composition test specimen. Evaluation method: After filling the prepared dental composition into a stainless steel mold, placing a cover glass on both sides and pressing the glass with a glass plate, using a photopolymerization irradiator (Griplight II: manufactured by Matsukaze Co., Ltd.) Light irradiation was performed at six locations for 30 seconds each to cure. After curing, after removing the cured product from the mold, both sides are lightly polished with sandpaper using # 1200,
The specimen from which the resin layer had been removed was used as a test specimen (15 φ × 1 mm: disk type). Thereafter, the test specimen was placed in a spectrophotometer (CM
-2002, manufactured by Minolta Co., Ltd.) and then placed in a 5.0% aqueous solution of instant coffee (Nescafe).
C. for 24 hours. After immersion for 24 hours, the test specimen was taken out, washed with water, and measured again. The color difference (ΔE * ab) was calculated using the colorimetric values before and after the immersion. The test was conducted for 5 specimens.
The test was performed individually and evaluated by the average value.

(4) Bending test evaluation purpose: To evaluate the bending strength of the dental composition test specimen. Evaluation method: After filling the prepared dental composition into a stainless steel mold, placing a cover glass on both sides and pressing the glass with a glass plate, using a photopolymerization irradiator (Griplight II: manufactured by Matsukaze Co., Ltd.) Light irradiation was performed at five locations for 30 seconds each to cure. After curing, the cured product was taken out of the mold, and the back surface was similarly irradiated with light again.
2 mm: rectangular parallelepiped). The specimen was heated at 37 ° C for 24 hours.
After immersion in water for hours, a bending test was performed. The bending test was performed using an Instron universal testing machine (Instron 5567, manufactured by Instron) at a distance between supporting points of 20 mm and a crosshead speed of 1 mm / min. In addition, the test was performed with 10 test pieces, and the average value was evaluated.

[Production of Raw Inorganic Particles] 43 parts by weight of silica, 20 parts by weight of aluminum oxide, 5 parts by weight of sodium fluoride
Parts by weight, 10 parts by weight of calcium fluoride, 5 parts by weight of calcium phosphate, and 17 parts by weight of strontium carbonate, the respective raw materials were sufficiently mixed, put into a high-temperature elema furnace at 1400 ° C. and moored for 5 hours to melt the raw materials. I let it. After melting, the mixture was cooled to produce glass as a filler material. The produced glass was pulverized with a ball mill for 12 hours, and passed through a 200-mesh sieve to obtain raw inorganic glass particles for wet pulverization. The average particle diameter of the raw inorganic glass particles was about 10 microns.

Example 1: Polyorganosiloxane coating
Preparation of inorganic filler "silane-treated POS filler 1" (wet pulverization) 4k diameter alumina cobblestone 4k in an alumina pot (internal volume 3.6 liters) of a quadruple vibration mill
g, 540 parts by weight of the raw material inorganic glass particles obtained above and 1,000 parts by weight of ion-exchanged water were added, and wet pulverization was performed for 40 hours. After pulverization, the average particle diameter and particle size distribution of the inorganic fine particles contained in the pulverized slurry were measured using a laser diffraction particle size analyzer (“Microtrack SP”).
A "(manufactured by Nikkiso Co., Ltd.). As a result, the particles had an average particle size of 1.2 μm and a monodispersed particle size distribution. After the pulverization, the alumina cobblestone and the pulverized slurry in the alumina pot were separated to obtain “pulverized slurry 1” as an aqueous dispersion.

(Formation of Polyorganosiloxane Film: P
OS processing) K. After charging 1500 parts by weight of the “pulverized slurry 1” into a combimix container and maintaining the mixture at 50 ° C., a low-condensation product of a silane compound “MS51SG1” (Si
O ₂ content of 16%, degree of polymerization of 2 to 6;
4.1 parts by weight and 8.7 parts by weight of 3-methacryloyloxypropylmethoxysilane were added, and the mixture was stirred and mixed for about 90 minutes. After mixing, the resulting treated slurry was aged in a hot air drier at 50 ° C. for 40 hours, heated to 120 ° C. and moored for 6 hours, and then cooled to obtain a heat-treated solid. The obtained heat-treated solid was placed in a Henschel mixer and crushed at 1800 rpm for 5 minutes to obtain a POS filler 1 whose surface was coated with polyorganosiloxane. The fluidity of the POS filler 1 at the time of this crushing was evaluated, and the average particle size and the particle size distribution were measured using a laser diffraction type particle size analyzer “Microtrack SPA”. As a result, the fluidity of the filler was good, the average particle diameter was 1.2 μm, and a monodispersed particle size distribution was exhibited. PO coated with the obtained polyorganosiloxane
S filler 1 was further subjected to 9 parts by weight of silane treatment using 3-methacryloyloxypropylmethoxysilane, which is an organosilane compound, to obtain "silane-treated POS filler 1".

Examples 2 and 3 The amount of 3-methacryloyloxypropylmethoxysilane used for the POS treatment in Example 1 was 17.4 parts by weight or 2 parts by weight.
Silane-treated POS fillers 2 and 3 were obtained in the same manner as in Example 1 except that the amount was changed to 6.1 parts by weight. Example 4 A silane-treated POS filler 4 was prepared in the same manner as in Example 1 except that 14.3 parts by weight of methyltriethoxysilane was used instead of 3-methacryloyloxypropylmethoxysilane used in the POS treatment in Example 1. Obtained.

Example 5: Polyorganosiloxane coating
Preparation of Inorganic Filler “Silane-Processed POS Filler 5” The procedure of Example 1 was repeated except that the pulverizing time was changed to 8 hours, to obtain “pulverized slurry 2” as an aqueous dispersion. The average particle size and particle size distribution of the inorganic fine particles contained in the pulverized slurry 2 were measured using a laser diffraction type particle size analyzer (“Microtrack SPA”; manufactured by Nikkiso Co., Ltd.). As a result, the average particle size was 3.2 μm. And a monodispersed particle size distribution.

(Formation of Polyorganosiloxane Film: P
OS processing) K. 1500 parts by weight of “Pulverized Slurry 2” is put into a container of Combimix, and 54.1 weight of a low condensate of a silane compound “MS51SG1” (SiO ₂ content 16%, polymerization degree 2 to 6; manufactured by Mitsubishi Chemical Corporation) is added. And 8.7 parts by weight of 3-methacryloyloxypropylmethoxysilane, respectively, and stirred and mixed for about 90 minutes. After mixing, the obtained treated slurry was aged in a hot air drier at 50 ° C. for 40 hours, heated to 150 ° C. and moored for 6 hours, and then cooled to obtain a heat-treated solid. The heat-treated solid obtained was placed in a Henschel mixer and the mixture was heated at 1800 rpm for 5 minutes.
The mixture was crushed for 1 minute to obtain a POS filler 5 whose surface was covered with polyorganosiloxane. P at the time of this crushing
The fluidity of the OS filler 5 was evaluated, and the average particle size and the particle size distribution were measured using a laser diffraction type particle size analyzer “Microtrack SPA”. As a result, the fluidity of the filler was good, the average particle diameter was 3.3 μm, and a monodispersed particle size distribution was exhibited. The obtained POS-treated filler 5 was further subjected to 6 parts by weight of silane treatment using 3-methacryloyloxypropylmethoxysilane, which is an organosilane compound, to obtain a silane-treated POS filler 5.

Comparative Examples 1 and 2 Each of the crushed slurries 1 and 2 obtained by wet pulverization in Examples 1 and 5 was aged at 50 ° C. for 40 hours in a hot-air dryer without polyorganosiloxane treatment. Then, the temperature was raised to 120 ° C. and moored for 6 hours, followed by cooling to obtain a heat-treated solid. The heat-treated solid thus obtained was placed in a Henschel mixer, and crushed at 1800 rpm for 5 minutes to obtain POS untreated fillers 1 and 2. The fluidity of the POS untreated fillers 1 and 2 at the time of this crushing was evaluated, and the average particle size and the particle size distribution were measured using a laser diffraction type particle sizer “Microtrack SPA”. The results are shown in Table 1. 9 parts by weight or 6 parts by weight of each of the obtained POS untreated fillers was treated with 3-methacryloyloxypropylmethoxysilane, which is an organosilane compound, to obtain silane-treated POS untreated fillers 6 and 7. .

[0036]

[Table 1]

Examples 6 to 10 and Comparative Examples 3 to 4 Resin compositions were prepared in the following composition ratios. [Resin composition] ・ 2,2-bis (4- (3-methacryloyloxy-2-hydroxypropoxy) phenyl) propane (Bis-GMA) 60 parts by weight ・ Triethylene glycol methacrylate (TEGDMA) 40 parts by weight ・ Camphorquinone 1 part by weight-1 part by weight of ethyl pN, N-dimethylaminobenzoate-18 parts by weight of ultrafine powdered silica (resin component thickener) 18 parts by weight For 100 parts by weight of the resin composition, obtained in Examples 1 to 4. Each of the silane-treated POS fillers 1 to 4 and the silane-treated POS untreated filler 6 obtained in Comparative Example 1 was 29
Dental compositions A-1 to A-4 (Examples 6 to 9) and Dental composition A-5 (Comparative Example 3) were prepared by mixing 6 parts by weight. In addition, the silane treatment P obtained in Example 5
OS filler 5 and silane-treated P obtained in Comparative Example 2
372 parts by weight of OS-untreated filler 7 was added to 100 parts by weight of the resin composition to prepare a dental composition A-6 (Example 10) and a dental composition A-7 (Comparative Example 4). Using these dental compositions, a toothbrush abrasion test, an abrasion test, a coloring resistance test, and a bending test were performed, and the results are shown in Table 2.

Example 11 A dental composition A-8 was prepared in the same manner as in Examples 6 to 9 except that the POS filler (without silane treatment) obtained in Example 1 was used. Various tests were performed. The results are shown in Table 2.

[0039]

[Table 2]

[0040]

According to the dental composition, by adding the inorganic filler of the present invention as a filler, excellent mechanical properties such as excellent polishing properties and surface lubricity are maintained while maintaining mechanical strength and resistance. Abrasion and coloring resistance can be improved.

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 4C089 AA06 BA04 BA11 BA13 BA16 CA06 4J002 BG041 DE096 DE146 DF016 DJ006 DJ016 DJ046 FB096 FD016 GB01 4J011 PA13 PA14 PA15 PA16 PB16 PB19 PB22 PC02 4J037 AAAAAAAAAA21 CA05 CA18 CA20 CB05 CB23 CB26 CC28 DD05 EE03 EE25 EE29 EE43 FF09 FF17 FF18 FF26

Claims (8)

[Claims] 1. The surface of inorganic fine particles having an average particle diameter of 0.01 to 5 μm is coated with a polyorganosiloxane, and the polyorganosiloxane has the general formula (I): (Where Z is RO— or OCN—, X is halogen, Y is OH—, R is an organic group having 8 or less carbon atoms, n, m, and L
Is an integer of 0 to 4 and n + m + L = 4) and a low condensate of the silane compound and a general formula (II): (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH—, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group, p is an integer of 1 to 3, a, b, and c are all 0 to
An integer of 3 and a + b + c + p = 4), a cocondensate hydrolyzed or partially hydrolyzed in the presence of an organosilane compound and / or a low condensate of an organosilane compound, or (2 ) The above general formula (I)
Or a low condensate of the silane compound and / or the organosilane compound and / or the low condensate of the organosilane compound represented by the general formula (II) in the presence of a metal compound. An inorganic filler that is a partially hydrolyzed cocondensate. 2. The polyorganosiloxane comprises: (1) a silane compound represented by the general formula (I) and / or a low condensate of the silane compound and the general formula (II)
The inorganic filler according to claim 1, wherein the inorganic filler is a cocondensate that has been hydrolyzed or partially hydrolyzed in the presence of an organosilane compound and / or a low condensate of the organosilane compound represented by the formula: 3. The polyorganosiloxane comprises: (2) a silane compound represented by the general formula (I) and / or a low condensate of the silane compound and the general formula (II)
The inorganic filler according to claim 1 or 2, wherein the inorganic filler is a cocondensate obtained by hydrolyzing or partially hydrolyzing an organosilane compound and / or a low condensate of the organosilane compound represented by the formula (1) in the presence of a metal compound. 4. The method according to claim 1, wherein the raw material inorganic particles have an average particle diameter of 0.0
A wet pulverization step of finely pulverizing into inorganic fine particles of 1 to 5 μm, or a wet dispersion step of pulverizing the aggregated inorganic fine particles into primary particles in which the primary particles have an average particle diameter of 0.01 to 5 μm, and (2) 2. The method for producing an inorganic filler according to claim 1, further comprising the step of :) forming a polyorganosiloxane film on the surface of the obtained inorganic fine particles. 5. The step of forming a polyorganosiloxane film comprises the step of: (2-1) in the presence of the above-mentioned inorganic fine particles dispersed in an aqueous medium, the general formula (I): (Where Z is RO— or OCN—, X is halogen, Y is OH—, R is an organic group having 8 or less carbon atoms, n, m, and L
Is an integer of 0 to 4 and n + m + L = 4) and a low condensate of the silane compound and a general condensate of the general formula (II): (Where Z is R ¹ O— or OCN—, X is halogen, Y
Is OH—, R ¹ is an organic group having 8 or less carbon atoms, R ² is an organic group, p is an integer of 1 to 3, a, b, and c are all 0 to
An integer of 3 and a + b + c + p = 4) is hydrolyzed or partially hydrolyzed in the presence of an organosilane compound and / or a low condensate of the organosilane compound, and then the obtained silanol compound And (2-3) heat treating the obtained aqueous dispersion, and (2-3) pulverizing the heat-treated solidified product into primary particles. The method according to claim 4 for producing the inorganic filler according to (2). 6. The step of forming a polyorganosiloxane comprises: (2-1) ′ a silane compound represented by the general formula (I) and / or a low condensate of the silane compound and a general formula (I)
Hydrolyzing or partially hydrolyzing the organosilane compound and / or a low-condensate of the organosilane compound represented by I) in the presence of a metal compound, and then co-condensing the obtained silanol compound, (2) The inorganic filler according to claim 1 or 3, comprising: -2) a step of heat-treating the obtained aqueous dispersion, and (2-3) 'a step of pulverizing the heat-treated solidified product into primary particles. The production method according to claim 4, for producing a. 7. (a) one of the inorganic fillers according to claims 1 to 3 and the inorganic filler obtained by the production method according to claims 4 to 6, (b) a polymerizable monomer, And (c) a polymerization initiator. 8. The dental composition according to claim 7, wherein the inorganic filler is dispersed and contained in a non-aggregated state.