JP2008260720A - Curable composition for dentistry - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a curable composition for dentistry, providing a cured article having high mechanical strength, and having good abrasivity and excellent operability. <P>SOLUTION: The curable composition for the dentistry comprises (A) a polymerizable monomer, (B) a mixed filler of silica-based metal oxide particles obtained by mixing (b1) surface-treated silica-based metal oxide particles I having large diameters and spherical or nearly spherical shapes, (b2) surface-treated silica-based metal oxide particles II having small diameters and spherical or nearly spherical shapes, and (b3) silica-based metal oxide fine particles III such as fumed silica, and (C) a polymerization initiator. The composition is preferably used as a composite restorative material for the dentistry. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a curable composition suitable as a dental composite restorative material. More specifically, the present invention provides a curable composition that gives a cured product having high mechanical strength, has good surface lubricity, and is excellent in operability over a wide temperature range.

  A dental composite restorative material is a composite material mainly composed of a polymerizable monomer, a polymerization initiator, and a filler, and can provide a color tone equivalent to a natural tooth color and is easy to operate. In recent years, it has been widely used as a material for repairing the skin.

  Specific uses of the dental composite restorative material include a filling composite resin that directly fills the cavity of a tooth by caries and the like, and a hard resin for a crown that can replace a part or the whole of a natural tooth crown. In these applications, it is required to have excellent mechanical properties and polishing properties after restoration. It is known that the filler plays a very important role for these physical properties. Various fillers have been studied so far, and some of them have been proposed which have both mechanical properties and polishing properties.

  For example, from 40 to 99% by mass of substantially spherical inorganic particles having an average particle diameter of more than 0.1 microns and 1 micron or less, and from 60 to 1% by mass of inorganic fine particles having an average particle diameter of 0.1 microns or less. A photocurable dental composite restorative material containing a filler and a polymerizable monomer is proposed (Patent Document 1). The restorative material is characterized by excellent bending strength, surface lubricity, and anti-abrasion resistance.

  Moreover, as a mixed filler of inorganic particles, (A) amorphous inorganic particles having an average particle diameter of 0.1 to 1 μm, (B) spherical inorganic particles having an average primary particle diameter of 0.1 to 5 μm, and (C) an average primary {MA / (mB + mC)} is 0.2 to 3, {mB / (mB + mC) when the fine inorganic particles having a particle diameter of 0.1 μm or less are set to mA, mB, and mC, respectively. } Is 0.5 to 0.99 and {mC / (mB + mC)} is blended so that it becomes 0.01 to 0.5. Reference 2). The restoration material has good operability, high fracture toughness when cured, and good surface lubricity.

JP 2000-26226 A International Publication No. 02/005752 Pamphlet

  However, the operability of these dental composite restorative materials has not always been satisfactory. That is, the restoration materials shown in Patent Documents 1 and 2 are materials that achieve both mechanical strength and abrasiveness by controlling the particle size distribution of fine particles of 1 micron or less. Because of the large amount, the paste became sticky, and stickiness was likely to appear when handled with a dental filling instrument (instrument). Although this problem could be alleviated to some extent by adjusting the filling rate, particularly when used in a high-temperature environment such as summer, the stickiness increased and the separation from the instrument was sometimes deteriorated.

  Therefore, the present invention has an object to provide a dental curable composition having both high mechanical strength and good surface smoothness, and having less stickiness of paste even in an environment with higher temperature and excellent operability. And

  The inventors of the present invention have made extensive studies to solve the above problems. As a result, a dental curable composition having good operability by using ultrafine particles having a primary particle size of several to several tens of nanometers in combination with a silica-based metal oxide composition having a specific particle size distribution and shape. The present invention was completed by finding out that a paste of 2 was obtained.

That is, the present invention comprises (A) 100 parts by mass of a polymerizable monomer,
(B) Silica-based metal oxide particle mixed filler having the following composition
200 to 700 parts by mass,
b1) Spherical or substantially spherical silica-based metal oxide particles I having an average primary particle size of 0.3 to 0.6 μm and surface-treated with an organosilicon compound 40 to 80% by mass
b2) Spherical or substantially spherical silica having an average primary particle diameter of b1) 1/8 to 1/4 of the average primary particle diameter of silica-based metal oxide particles I and surface-treated with an organosilicon compound -Based metal oxide particles II
15-55% by mass
b3) Silica-based metal oxide fine particles III having an average primary particle diameter of 5 to 30 nm 0.5 to 5% by mass
(C) Polymerization initiator A dental curable composition comprising 0.01 to 5 parts by mass.

  The dental curable composition of the present invention is not only characterized by the high mechanical strength and excellent surface lubricity of the cured product that the conventional dental restorative material had, but under various temperature environments, It has the characteristics of good operability with less stickiness of the paste. In particular, such an adverse phenomenon can be satisfactorily suppressed even at a temperature of 28 to 40 ° C. where the stickiness becomes severe and the operability with a dental filling instrument is lowered, which is extremely useful.

  The dental curable composition of the present invention is composed at least of components of (A) a polymerizable monomer, (B) a silica-based metal oxide particle mixed filler having a specific composition, and (C) a polymerization initiator. Is done.

In the present invention, any known polymerizable monomer (A) can be used without limitation. Examples of the polymerizable monomer that can be suitably used include a radical polymerizable monomer having an acryloyl group and / or a methacryloyl group. Specific examples of such a polymerizable monomer include the following [I-1 ] To [I-4].
[I-1] Monofunctional vinyl monomer: Methacrylate such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hydroxyethyl methacrylate, tetrahydrofurfuryl methacrylate, glycidyl methacrylate, and acrylates corresponding to these methacrylates; or acrylic acid, methacrylic acid, p-methacryloyloxybenzoic acid, N-2-hydroxy-3-methacryloyloxypropyl-N-phenylglycine, 4-methacryloyloxyethyl trimellitic acid and its anhydride, 6-methacryloyloxyhexamethylenemalonic acid, 10-methacryloyl Oxydecamethylenemalonic acid, 2-methacryloyloxyethyl dihydrogen phosphate, 10-methacryloyloxydecame Chilene hydrogen phosphate, 2-hydroxyethyl hydrogen phenyl phosphonate, etc.
[I-2] Bifunctional vinyl monomer (i) Aromatic compound-based 2,2-bis (methacryloyloxyphenyl) propane, 2,2-bis (4-methacryloyloxyethoxyphenyl) propane (hereinafter referred to as bis-) MEPP), 2,2-bis [4- (3-methacryloyloxy) -2-hydroxypropoxyphenyl] propane (hereinafter abbreviated as bis-GMA), 2,2-bis (4-methacryloyloxyphenyl) ) Propane, 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane (hereinafter abbreviated as bis-MPEPP), 2,2-bis (4-methacryloyloxydiethoxyphenyl) propane), 2,2- Bis (4-methacryloyloxytetraethoxyphenyl) propane, 2,2-bis (4-methacrylic) (Royloxypentaethoxyphenyl) propane, 2,2-bis (4-methacryloyloxydipropoxyphenyl) propane, 2 (4-methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxydiethoxyphenyl) propane, 2 (4 -Methacryloyloxydiethoxyphenyl) -2 (4-methacryloyloxyditriethoxyphenyl) 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; Methacrylates such as acrylate, 2-hydroxypropyl methacrylate, 3-chloro-2-hydroxypropyl methacrylate, etc., or vinyl monomers having —OH groups such as acrylates corresponding to these methacrylates, diisocyanate methylbenzene, 4,4′- Diaducts obtained from addition with a diisocyanate compound having an aromatic group such as diphenylmethane diisocyanate.
(Ii) Aliphatic compounds of ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate (hereinafter abbreviated as TEGDMA), butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, propylene glycol dimethacrylate, 1, 3-butanediol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate (hereinafter abbreviated as HDDM), and acrylates corresponding to these methacrylates; 2-hydroxyethyl methacrylate, 2- Methacrylates such as hydroxypropyl methacrylate and 3-chloro-2-hydroxypropyl methacrylate, or polymers corresponding to these methacrylates A diadduct obtained from the addition of a vinyl monomer having an -OH group such as relate and a diisocyanate compound such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diisocyanate methylcyclohexane, isophorone diisocyanate, methylenebis (4-cyclohexylisocyanate), For example, 1,6-bis (methacrylethyloxycarbonylamino) -2,2-4-trimethylhexane (hereinafter abbreviated as UDMA); acrylic acid anhydride, methacrylic acid anhydride, 1,2-bis (3-methacryloyloxy- 2-hydroxypropoxy) ethyl, di (2-methacryloyloxypropyl) phosphate and the like.
[I-3] Trifunctional vinyl monomers such as trimethylolpropane trimethacrylate, trimethylolethane trimethacrylate, pentaerythritol trimethacrylate, trimethylolmethane trimethacrylate (hereinafter abbreviated as TMPT), and methacrylates thereof. Corresponding acrylate etc.
[I-4] Tetrafunctional vinyl monomers pentaerythritol tetramethacrylate, pentaerythritol tetraacrylate and diisocyanate methylbenzene, diisocyanate methylcyclohexane, isophorone diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, methylenebis (4-cyclohexyl isocyanate), 4 Diadducts obtained from the addition of diisocyanate compounds such as 1,4-diphenylmethane diisocyanate and tolylene-2,4-diisocyanate and glycidol dimethacrylate.

  The above polymerizable monomers may be used alone or in combination of two or more. In particular, it is preferable to use a mixture of two or more types in order to adjust the mechanical strength, refractive index, and viscosity. Examples of polymerizable monomers suitable for obtaining good operability include polymerizable monomer compositions mainly composed of bis-MEPP, bis-MPEPP, TEGDMA, HDDM, or TMPT.

In the present invention, (B) the silica-based metal oxide particle mixed filler is a mixed filler having a specific blending ratio of the following three types of silica-based metal oxide particles.
b1) Spherical or substantially spherical silica-based metal oxide particles having an average primary particle size of 0.3 to 0.6 μm, more preferably 0.45 to 0.58 μm, and surface treatment with an organosilicon compound I
40-80% by mass
b2) Organosilicon compound having an average primary particle diameter of b1) 1/8 to 1/4 of the average primary particle diameter of silica-based metal oxide particles I, more preferably 1 / 5.5 to 1 / 4.5 Spherical or substantially spherical silica-based metal oxide particles II surface-treated with
15-55% by mass
b3) Silica-based metal oxide fine particles III having an average primary particle diameter of 5 to 30 nm 0.5 to 5% by mass
Here, in this invention, the primary particle diameter of each silica type complex oxide particle which consists of b1) -b3) is a circle equivalent diameter (the same as the area of an object particle | grain) from the picked-up image of a scanning type or a transmission type electron microscope. The diameter of a circle having an area is measured by image analysis. As an electron microscope image used for measurement, an image that is clear and bright and capable of discriminating the outline of the particle is used. As an image analysis method, an image that can measure at least the area of the particle, the maximum length of the particle, and the minimum width is used. Use analysis software. Further, the average particle diameter, coefficient of variation, and average uniformity of these primary particles are calculated from the primary particle diameter measured as described above by the following formula.

Here, the number of particles (n), the maximum length of the particles is the major axis (Li), and the diameter perpendicular to the major axis is the minimum width (Bi).

  When calculating these values, it is necessary to measure at least 40 or more particles in order to maintain measurement accuracy, and it is desirable to measure 100 or more particles.

  In this silica-based metal oxide particle mixed filler, by using a combination of b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II, the filler filling rate can be greatly increased. . That is, b1) silica-based composite oxide particles I having a relatively large particle size with an average primary particle size of 0.3 to 0.6 μm, and b2) having a size of 1/8 to 1/4 of the average primary particle size. By using together the silica-based composite oxide particles II, the gap between the former large particles is filled with the latter small particles, and as a result approaches the closest packing, the filling rate can be remarkably increased. . As a result, the obtained dental curable composition has greatly improved mechanical strength of the cured product, and has excellent basic physical properties as a dental curable composition such as low water absorption solubility, small thermal expansion coefficient and polymerization shrinkage ratio. Will have. Moreover, b1) By using the silica-based composite oxide particles I within the above particle diameter range, the cured product has excellent surface lubricity and can be easily polished in a short time with good polishing. It can be made with the nature.

  Further, b3) Fine (average primary particle diameter 5 to 30 nm) silica-based metal oxide fine particles in a mixed filler in which b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II are used in combination. By blending III, the stickiness when the dental curable composition paste is handled with a dental filling instrument can be greatly improved.

  Here, in the b1) silica-based metal oxide particles I, when the average primary particle diameter exceeds 0.6 μm, the surface smoothness of the cured product of the dental curable composition is inferior, and this average primary When the particle diameter is less than 0.3 μm, sufficient mechanical strength cannot be obtained. The variation in primary particles of the b1) silica-based metal oxide particles I is preferably as small as possible, and those having a primary particle diameter variation coefficient of 30% or less are usually used. Furthermore, the coefficient of variation of the primary particle diameter is preferably 20% or less, and most preferably 10% or less.

  The b1) silica-based metal oxide particles I in the present invention are silica or a metal oxide containing silica as a main component, and crystalline ones can be used, but amorphous ones are preferred. Specific examples include silica, silica-titania, silica-zirconia, silica-barium oxide, silica-alumina, silica-calcia, silica-strontium oxide, silica-magnesia, silica-titania-sodium oxide, silica-titania-potassium oxide. Silica-zirconia-sodium oxide, silica-zirconia-potassium oxide, silica-alumina-sodium oxide, silica-alumina-potassium oxide, and the like.

  The shape of the b1) silica-based metal oxide particles I is spherical or substantially spherical. In addition, the substantially spherical shape here means that the average degree of homogeneity obtained in the image analysis of the captured image of the scanning or transmission electron microscope is 0.6 or more. The average uniformity is more preferably 0.7 or more, and further preferably 0.8 or more.

  The production method of the silica-based metal oxide particles having the properties used as b1) is not particularly limited, and any method of liquid phase reaction and gas phase reaction is possible, but the variation coefficient of the primary particle diameter is small and spherical. Since it is easy to obtain particles of at least one selected from the group consisting of a hydrolyzable organosilicon compound, or a group consisting of metals of Groups I, II, III, and IV of the periodic table A mixed solution containing a hydrolyzable organic compound containing a seed metal is added to an alkaline solvent that dissolves these raw materials but does not substantially dissolve the reaction product, and performs hydrolysis to precipitate the reaction product. The so-called sol-gel method is preferably employed.

  The silica-based metal oxide particles produced by such a method are preferably baked at a temperature of 500 to 1000 ° C. after drying in order to maintain the surface stability. Further, since the particles are aggregated during firing, it is preferable to use the particles after the aggregated particles are unwound using a jet mill, a vibration ball mill or the like to adjust the particle size. Even if such an operation is performed, it is difficult to completely bring the aggregated particles into a state before aggregation. When the heat treatment as described above is performed, the primary particles of the silica-based composite oxide, the aggregates thereof, However, unlike the case of adding independent particles with a large particle size, even if some agglomerates are included, the lubricity and wear resistance after polymerization and curing are substantially reduced. If there is no adverse effect, it does not matter.

  In the present invention, the above-mentioned b1) silica-based metal oxide particles I are organic from the viewpoint of improving the familiarity with (A) the polymerizable monomer and improving the mechanical strength of the cured product and the operability of the paste. It is used after being surface-treated with a silicon compound. As this surface treatment, a known surface treatment agent composed of an organosilicon compound and a known surface treatment method using them can be suitably employed. Examples of suitable surface treatment agents include alkoxysilane-based silane coupling agents such as methyltrimethoxysilane and γ-methacryloyloxypropyltrimethoxysilane, hydrolysates thereof, monofunctional silane compounds such as trimethylsilanol, hexa Examples thereof include silazane such as methyldisilazane, silicone oil and the like. The treatment amount of these surface treatment agents may be an amount necessary for coating the particle surface. Generally, a surface treating agent is used in the range of 0.1-30 mass parts with respect to 100 mass parts of the silica type metal oxide I.

  (B) In the silica-based metal oxide particle mixed filler, b2) silica-based metal oxide particle II is 1/8 to 1/4 of the average primary particle diameter of b1) silica-based metal oxide particle I described above. It is. When the average primary particle size is smaller or larger than the above value, the filling rate of the filler is lowered, so that the basic physical properties of the cured product of the dental curable composition of the present invention are lowered to those which cannot be sufficiently satisfied. .

  Also in b2) silica-based metal oxide particles II, the coefficient of variation of the primary particle diameter is usually 30% or less, more preferably 20% or less, and most preferably 10% or less. The shape is also spherical or substantially spherical as in the case of b1) silica-based metal oxide particles I, and the average uniformity in the case of the substantially spherical shape is 0.6 or more and 0.7 or more. More preferably, it is 0.8 or more.

  The kind of the metal oxide is also the same as that described for b1) silica-based metal oxide particles I, and silica or a metal oxide containing silica as a main component as exemplified therein can be used without limitation. At this time, the same material as b1) silica-based metal oxide particles I or a different material may be used.

  Furthermore, the production method of b2) silica-based metal oxide particles II can be adopted without limitation the same method as described in b1) silica-based metal oxide particles I. What is necessary is just to manufacture suitably as a thing of 1/8-1/4 of an average primary particle diameter.

  This b2) silica-based metal oxide particle II is also surface-treated with an organosilicon compound from the viewpoint of improving compatibility with (A) the polymerizable monomer and improving the mechanical strength of the cured product and the operability of the paste. The surface treatment agent and the surface treatment method are the same as those in the case of b1) silica-based metal oxide particles I described above.

  (B) Silica-based metal oxide fine particle III having an average primary particle size of 5 to 30 nm, which is blended in the silica-based metal oxide particle mixed filler, is an extremely important component for suppressing stickiness of the paste. is there. If the average primary particle size is outside the above fine range, the paste of the dental curable composition becomes sticky, and the handleability with a dental filling device is greatly reduced. A more preferable range of the average primary particle diameter of this b3) silica-based metal oxide fine particle III is in the range of 10 to 28 nm. Note that these particles may be formed by agglomerating primary particles to form sub-micron secondary agglomerated particles.

  In the present invention, the b3) silica-based metal oxide fine particles III may be appropriately selected from the materials exemplified for the b1) silica-based metal oxide particles I. In this case, the material may be the same as or different from b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II. Silica group metal oxide obtained by gas phase reaction because the number of silanol groups on the particle surface is small and dispersibility is good, transparency is high, and the effect of suppressing stickiness of the paste is also particularly good. Of these, fumed silica is most preferable. The shape and production method of the silica-based metal oxide (C) are not particularly limited.

  These b3) silica-based metal oxide fine particles III may be used as they are, but they are surface-treated with an organosilicon compound in the same manner as b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II. Is preferably used from the viewpoint of improving the compatibility with the polymerizable monomer (A) and improving the dispersibility so as to exhibit the above-described blending effect more favorably. The surface treatment agent and the surface treatment method used in this case may be carried out in the same manner as the surface treatment with b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II.

  In this invention, the compounding quantity of the silica type metal oxide particle mixed filler which consists of said each composition is 200-700 mass parts with respect to 100 mass parts (A) polymeric monomer. Further, a more preferable blending ratio is 300 to 600 parts by mass. When the compounding amount of the silica-based metal oxide particle mixed filler is less than 200 parts by mass, the mechanical properties of the cured body of the dental curable composition are inferior, and the effect of suppressing stickiness of the paste is not sufficient. On the other hand, when the compounding quantity of a silica type metal oxide particle mixing filler exceeds 700 mass parts, uniform mixing with (A) a polymerizable monomer will become difficult, and it will become difficult to make a paste state.

  In the dental curable composition of the present invention, any known polymerization initiator (C) can be used without limitation. The polymerization method of the curable composition includes a reaction by light energy such as ultraviolet light and visible light (hereinafter referred to as photopolymerization), a chemical reaction between a peroxide and an accelerator, and a heating method. Various polymerization initiators shown below may be appropriately selected and used according to the polymerization method.

  For example, examples of the photopolymerization initiator include benzoin alkyl ethers such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, benzyl ketals such as benzyldimethyl ketal and benzyl diethyl ketal, benzophenone, 4,4′-dimethylbenzophenone, Benzophenones such as 4-methacryloxybenzophenone, diacetyl, 2,3-pentadionebenzyl, camphorquinone, 9,10-phenanthraquinone, α-diketones such as 9,10-anthraquinone, 2,4-diethoxy Thioxane compounds such as thioxanthone, 2-chlorothioxanthone, methylthioxanthone, bis- (2,6-dichlorobenzoyl) phenylphosphine oxide, bis- (2,6-dichlorobenzoy ) -2,5-dimethylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -4-propylphenylphosphine oxide, bis- (2,6-dichlorobenzoyl) -1-naphthylphosphine oxide, 2,4 Acylphosphine oxides such as 1,6-trimethylbenzoyldiphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide can be used.

  Incidentally, a reducing agent is often added to the photopolymerization initiator. Examples thereof include tertiary amines such as 2- (dimethylamino) ethyl methacrylate, ethyl 4-dimethylaminobenzoate, and N-methyldiethanolamine. , Aldehydes such as lauryl aldehyde, dimethylaminobenzaldehyde, terephthalaldehyde, and sulfur-containing compounds such as 2-mercaptobenzoxazole, 1-decanethiol, thiosalicylic acid, and thiobenzoic acid.

  Examples of the thermal polymerization initiator include benzoyl peroxide, p-chlorobenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl peroxydicarbonate, and diisopropyl peroxydicarbonate. Peroxides, azo compounds such as azobisisobutyronitrile, tributylborane, tributylborane partial oxide, sodium tetraphenylborate, sodium tetrakis (p-fluorophenyl) borate, triethanolamine tetraphenylborate And boron compounds such as 5-butyl barbituric acid, 1-benzyl-5-phenyl barbituric acid and the like, and sulfinates such as sodium benzenesulfinate and sodium p-toluenesulfinate. .

  Among these polymerization initiators, the use of a photopolymerization initiator is preferable from the viewpoint of easy operation during use, and camphorquinone, bis (2,4,6-trimethylbenzoyl) -phenyl is particularly preferable. Examples include phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylphenylphosphine oxide.

  These (C) polymerization initiators may be used alone or in admixture of two or more. (C) The compounding quantity of a polymerization initiator is 0.01-5 mass parts with respect to 100 mass parts of (A) polymeric monomer. When the blending amount of the (C) polymerization initiator is less than 0.01 parts by mass, curing is insufficient, and when it is more than 5 parts by mass, the stability against environmental light is lowered, which is not preferable. (A) The more preferable compounding quantity of a polymerizable monomer is 0.1-3 mass parts with respect to 100 mass parts of (A) polymerizable monomers.

  In addition to the (B) silica-based metal oxide particle mixed filler, other filler components may be blended in the dental curable composition of the present invention as long as the effects of the present invention are not significantly impaired. Examples of such other fillers include inorganic fillers such as alumina, titania and zirconia, organic fillers such as polymethyl methacrylate, and organic-inorganic composite fillers. These have an average primary particle size of 0.1 to 5 μm. Are generally used. Further, silica-based metal oxide particles other than those specified by b1) to b3) can be used as long as the conditions of the average primary particle diameter and particle shape are not significantly impaired. . In particular, (D) by adding silica-based metal oxide particles IV, which are amorphous particles, having an average primary particle size of 0.5 to 2 microns, mechanical strength, particularly toughness, can be further increased, It is preferable because the sticking suppression effect is further improved.

  The (D) silica-based metal oxide particles IV are indefinite from the viewpoint of improving the mechanical strength. Here, the irregular shape in the present invention means that the shape of the primary particles observed by SEM or the like has a large number of irregular corners and surfaces, and particles usually obtained by crushing or grinding. Point to. Further, the material may be appropriately selected from those exemplified for the b1) silica-based metal oxide particles I and used. At this time, the material may be the same as or different from each silica-based metal oxide particle constituting the (B) silica-based metal oxide particle mixed filler.

  The method for producing such (D) silica-based metal oxide particles IV is also not particularly limited, but is preferably obtained by pulverizing a bulk body because amorphous particles are easily obtained. The silica-based metal oxide particles IV are also preferably surface-treated with an organosilicon compound, and the surface treatment conditions may be appropriately selected from the methods described above.

  (D) The suitable compounding amount of the silica-based metal oxide particles IV is 10 to 65 parts by mass, and more preferably 20 when the silica-based composite oxide particle mixed filler is 100 parts by mass. -45 parts by mass.

  The dental curable composition of the present invention may be added with known additives such as a polymerization inhibitor, an antioxidant, a pigment, an ultraviolet absorber, a fluorescent agent and the like as long as the effects of the present invention are not impaired. Can be appropriately blended.

  Next, in the dental curable composition of the present invention, the method of mixing the above-described components into a paste is not particularly limited, and may be appropriately performed by a known mixing method. The (B) silica-based metal oxide particle mixed filler may be added to and mixed with all of the components b1) to b3) with respect to the (A) polymerizable monomer. Prior to mixing with the polymerizable monomer, it is preferable to premix at least two of them. This premixing is generally carried out by a method in which desired silica-based metal oxide particles are blended in an appropriate dispersion medium, processed in a disperser and then dried. At this time, it is efficient to simultaneously perform a surface treatment step on the silica-based metal oxide particles to be premixed by adding a surface treatment agent.

  Preferable examples of the dispersion medium include polar solvents such as water, methanol, ethanol, propanol, butanol, acetone, and mixed solvents thereof. As the disperser, generally known emulsifying dispersers, wet crushers, wet crushers and the like are used. Specific examples include a homogenizer, a ball mill, a bead mill, and an ultra-high pressure impact type emulsifying dispersion device. The dispersion does not need to be performed at a particularly limited temperature, and is generally performed at around room temperature, for example, in the range of 10 to 60 ° C. The mixing ratio of the silica-based metal oxide particles and the dispersion medium may be in a range that makes a slurry, and the dispersion medium is generally used in the range of 200 to 1000 parts by mass with respect to 100 parts by mass of the particles. The dispersion is preferably performed until the silica-based metal oxide particles do not settle upon standing for 1 hour. The dispersion is generally dried with a spray dryer.

  (A) A polymerizable monomer, (B) a silica-based metal oxide particle mixed filler, (C) a polymerization initiator, and a method of mixing each optional component to form a dental curable composition, these components May be sufficiently uniformly kneaded using a mixer or a likai machine. In this case, (B) silica-based metal oxide particle mixture for a polymerized monomer mixed with a polymerization initiator and various additives (hereinafter also referred to as a polymerizable monomer composition). Although the method of gradually adding the filler may be performed, since the finer particles are more likely to aggregate, first, the b3) silica-based metal oxide fine particles III, which are fine particles, are mixed with the polymerizable monomer (A). Mix well with a mixer or a lycra machine over a period of about 2 to 30 minutes, and gradually add a premixed mixture of b1) silica-based metal oxide particles I and b2) silica-based metal oxide particles II by the above method. It is suitable to perform a method of mixing. The obtained paste of the dental curable composition is preferably further degassed under reduced pressure.

  Although the use of the dental curable composition of the present invention is not particularly limited, a dental composite restorative material is preferable. As a specific example, it can be used effectively for a crown restorative material, etc., but it is used for a dental filling composite resin. It is particularly preferable to do this. As a general method of using a dental filling composite resin, the dental cavity to be restored is treated with an appropriate pretreatment agent or adhesive, and then directly filled with the dental filling composite resin. And a method of polymerizing and curing by irradiating strong light.

EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not restrict | limited to these Examples. The polymerizable monomers, polymerization initiators, and silica-based metal oxide particles used in the examples and comparative examples are as follows.
● Silica-based composite oxide particles:
B1-1: Silica particles average particle size 0.38 μm, spherical shape (average uniformity 0.9), coefficient of variation of primary particle size 4%
B1-2: Silica titania particle average particle diameter 0.42 μm, spherical shape (average uniformity 0.9), coefficient of variation of primary particle diameter 8%
B1-3: Silica zirconia particles average particle size 0.57 μm, spherical shape (average uniformity 0.7), coefficient of variation of primary particle size 23%
B1-4: Silica zirconia particle average particle size 0.42 μm, spherical shape (average uniformity 0.8), coefficient of variation of primary particle size 13%
B2-1: Silica titania particle average particle size 0.08 μm, spherical shape (average uniformity 0.9), coefficient of variation of primary particle size 8%
B2-2: Silica zirconia particle average particle size 0.07 μm, spherical shape (average uniformity 0.9), coefficient of variation of primary particle size 18%
B3-1: fumed silica ("Leoro Seal QS-102"; manufactured by Tokuyama Corporation)
Average primary particle size 12nm
B3-2: fumed silica (“Leosil MT-10”; manufactured by Tokuyama Corporation)
Hydrophobic grade having an average primary particle size of 12 nm and surface-treated with an organosilicon compound. B3-3: Surface treatment of fumed silica (“Leolosil QS-30”; manufactured by Tokuyama) with γ-methacryloyloxypropyltrimethoxysilane. Average primary particle size 7nm
B3-4: Fumed silica (“Aerosil R972”; manufactured by Nippon Aerosil Co., Ltd.)
Average primary particle size 27 nanometers D-1: Finely pulverized barium glass ("GM27884"; manufactured by SCHOTT)
Average particle size 0.7 μm, irregular shape, D-2: finely pulverized silica zirconia Average particle size 0.95 μm, irregular shape ● Polymerizable monomer:
UDMA: 1,6-bis (methacrylethyloxycarbonylamino) -2,2-4-trimethylhexane TEGDMA: triethylene glycol dimethacrylate bis-MPEPP: 2,2-bis (4-methacryloyloxypolyethoxyphenyl) propane Polymerization initiator:
CQ: camphorquinone DMBE: dimethylaminobenzoic acid ethyl ester DMPT: dimethyl paratoluidine TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide (1) Average particle size, coefficient of variation Scanning electron microscope (hereinafter referred to as SEM) From the photographed image obtained using the image, processing was performed with image analysis software (IP-1000PC manufactured by Asahi Kasei Engineering Co., Ltd.), and the equivalent circle diameter and the number of particles of the primary particles in the unit field of view were obtained. The number of particles was 100 or more. The average volume diameter of the primary particles was determined by the following formula and was defined as the average particle diameter. In addition, the coefficient of variation of the primary particle size was calculated.

(2) Average homogeneity From a photographed image obtained using a scanning electron microscope (hereinafter referred to as SEM), the image is processed by image analysis software (IP-1000PC manufactured by Asahi Kasei Engineering Co., Ltd.), and each primary in the unit field of view. The maximum length, minimum width, and number of particles were determined. The number of particles was 100 or more. The number of primary particles observed in the unit visual field (n), the maximum length of the primary particles as the major axis (Li), and the diameter perpendicular to the major axis as the minimum width (Bi), find n, Li, Bi, It was calculated by the following formula.

(3) Adhesiveness (Evaluation of stickiness of paste)
A mold having a diameter of 8 mm and a height of 10 mm was filled with the curable composition paste and kept at 30 ° C. in the dark. A cylindrical stainless steel rod having a diameter of 5 mm was infiltrated into the paste by 2 mm from the state in contact with the paste surface, and then the rod was pulled out. When the initial paste surface coordinates were 0, the paste adhered to the stainless steel and rose, and the distance to the distant coordinates was defined as adhesion [mm].
(4) Bending strength A prismatic sample piece of 2 × 2 × 25 mm was bent with a tester (manufactured by Shimadzu Corp., Autograph AG-5000D) at a distance between fulcrums of 20 mm and a crosshead speed of 1 mm / min. The strength was measured.
(5) Surface smoothness A prismatic mold having a width of 2 × height of 4 × length of 20 mm is filled with a curable paste, sufficiently cured by photopolymerization, taken out from the mold, and 37 ° C. water. For 24 hours. The surface of the sample piece was polished with water-resistant polishing paper No. 1500, and then polished with Soflex-Superfine (manufactured by 3M) for 1 minute, and the glossiness of the surface was visually determined. A case where the lubricity was excellent was evaluated as “good”, and a case where the lubricity was inferior was evaluated as “x”.
(6) Preparation of polymerizable monomer composition M-1: Uniform polymerizable monomer composition by adding and mixing 0.5 mass% CQ and 0.5 mass% DMPT to 70 g of UDMA and 30 g of TEGDMA A product was prepared and this was designated as matrix M-1.

  M-2: To 70 g of bis-MPEPP and 30 g of TEGDMA, 0.5% by mass of CQ and 0.5% by mass of DMBE were added and mixed to prepare a uniform polymerizable monomer composition. -2.

  M-3: Bis-MPEPP 70 g, TEGDMA 15 g, and UDMA 15 g were mixed with 0.5% by mass of TPO to prepare a uniform polymerizable monomer composition, which was designated as matrix M-3.

Moreover, the silica type metal oxide particle mixed filler was adjusted by the method shown below.
Production Example 1
440 g of b1-1 and 540 g of b2-1 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-1 was obtained.
Production Example 2
590 g of b1-2 and 390 g of b2-2 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-2 was obtained.
Production Example 3
690 g of b1-2 and 290 g of b2-2 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-3 was obtained.
Production Example 4
61-2 g of b1-2, 290 g of b2-2, and 25 g of b3-1 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-4 was obtained.
Production Example 5
590 g of b1-3, 390 g of b2-1, and 20 g of b3-4 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-5 was obtained.
Production Example 6
590 g of b1-2 and 390 g of b2-1 were mixed in 4 L of pure water and dispersed using a large-circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-6 was obtained.
Production Example 7
600 g of b1-2 and 400 g of b3-1 were mixed in 4 L of pure water and dispersed using a mass circulation bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-7 was obtained.
Production Example 8
600 g of b2-2 and 400 g of b3-1 were mixed in 4 L of pure water and dispersed using a mass circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-8 was obtained.
Production Example 9
290 g of b1-2 and 690 g of b2-2 were mixed in 4 L of pure water and dispersed using a mass circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-9 was obtained.
Production Example 10
290 g of b1-1 and 690 g of b1-2 were mixed in 4 L of pure water and dispersed using a mass circulation type bead mill. Add γ-methacryloxypropyltrimethoxysilane hydrolyzed in acetic acid aqueous solution to the dispersion, stir, then spray dry with spray dryer, and further heat drying under reduced pressure to mix silica metal oxide particles Filler F-10 was obtained.
Example 1
100 g of the polymerizable monomer composition M-1 and 7 g of b3-2 were charged into a mixer kept at 55 ° C. and mixed in advance for 1 hour. Next, the silica-based metal oxide particle mixed filler F-1 was mixed little by little, and finally 350 g was added to form a paste. Furthermore, this paste was degassed under reduced pressure to obtain a curable composition.

About the obtained paste of the curable composition, adhesiveness, bending strength of the cured body, and surface smoothness were measured. The results are shown in Table 1.
Examples 2-10
Each curable composition was obtained in the same manner as in Example 1 except that the polymerizable monomer composition and the silica-based oxide particle mixed filler to be blended were changed as shown in Table 1. About the obtained paste of the curable composition, adhesiveness, bending strength of the cured body, and surface smoothness were measured. The results are shown in Table 1.
Comparative Example 1
To 100 g of the polymerizable monomer composition M-2, the silica-based metal oxide particle mixed filler F-2 was mixed little by little, and finally 420 g was added to form a paste. Furthermore, this paste was degassed under reduced pressure to obtain a curable composition. About the obtained paste of the curable composition, adhesiveness, bending strength of the cured body, and surface smoothness were measured. The results are shown in Table 1.
Comparative Examples 2-7
Each curable composition was obtained in the same manner as in Example 1 except that the polymerizable monomer composition and the silica-based oxide particle mixed filler to be blended were changed as shown in Table 1. About the obtained paste of the curable composition, adhesiveness, bending strength of the cured body, and surface smoothness were measured. The results are shown in Table 1.

Claims (4)

(A) polymerizable monomer 100 parts by mass,
(B) Silica-based metal oxide particle mixed filler having the following composition
200 to 700 parts by mass,
b1) Spherical or substantially spherical silica-based metal oxide particles I having an average primary particle size of 0.3 to 0.6 μm and surface-treated with an organosilicon compound 40 to 80% by mass
b2) Spherical or substantially spherical silica having an average primary particle diameter of b1) 1/8 to 1/4 of the average primary particle diameter of silica-based metal oxide particles I and surface-treated with an organosilicon compound -Based metal oxide particles II
15-55% by mass
b3) Silica-based metal oxide fine particles III having an average primary particle diameter of 5 to 30 nm 0.5 to 5% by mass
(C) Polymerization initiator Dental curable composition comprising 0.01 to 5 parts by mass.   The dental curable composition according to claim 1, wherein b3) the silica-based metal oxide fine particles III are fumed silica.   Further, (D) silica-based metal oxide particles IV, which are amorphous particles having an average primary particle diameter of 0.5 to 2 μm, are added to 10 parts by mass of (B) 100 parts by mass of silica-based oxide particle mixed filler. The dental curable composition according to claim 1 or 2, comprising ~ 65 parts by mass.   It is a dental composite restorative material, The dental curable composition as described in any one of Claims 1-3.