Opaque dental curable composition for additive manufacturing

Abstract

To provide a laminate molding dental curable composition having certain transparency before molding and increased opacity after the molding and used for optical molding.SOLUTION: The laminate molding dental curable composition includes 0.1-10 pts.wt of a photoinitiator (b), 5-30 pts.wt. of a nonpolymerizable polymer (c), and (d) 1.0-10 pts.wt of a fine particle filler (d), with respect to 100 pts.wt of a radical polymerizable monomer (a). The radical polymerizable monomer (a) has a refractive index of 1.45-1.57, the nonpolymerizable polymer (c) has an average molecular weight of 2,000-5,000 g / mol, and the fine particle filler (d) has an average primary particle diameter of 0.001 μm-1 μm.SELECTED DRAWING: None

Description

Technical Field

[0005]

[0001] The present invention relates to a dental curable composition that can be suitably used when producing a shaped object by a laminating shaping apparatus.

Background Art

[0002] Currently, in the field of dental medicine, curable compositions mainly composed of radically polymerizable monomers are used in many treatment methods. Conventionally, dental restorations using curable compositions have been produced by the manual work of dentists or dental technicians. However, in recent years, digitalization has been rapidly progressing in the field of dental medicine, and laminating shaping technology using a laminating shaping apparatus has begun to spread. Therefore, a dental curable composition for laminating shaping suitable for the dental field is required.

[0003] This laminating shaping method is one of the methods called "optical shaping" in which a photocurable composition is irradiated with light to produce a cured body. In this laminating shaping method, a cured layer is formed by irradiating light of a shape pattern, and this is continuously performed to laminate the cured layers to obtain a desired cured body. The photocurable composition used in this laminating shaping method is required to rapidly cure by the irradiated light and not cure in the portions where light is not irradiated.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Compositions used in stereolithography are required to have a certain degree of transparency because they harden with light energy. If the composition is highly opaque, light energy cannot reach the interior, making stereolithography difficult. On the other hand, dental compositions require opacity depending on their application. The present invention aims to provide a dental curable composition for additive manufacturing used in stereolithography that has a certain degree of transparency before fabrication and becomes more opaque after fabrication. [Means for solving the problem]

[0006] The present invention comprises (a) 100 parts by weight of a radical polymerizable monomer, (b) 0.1 to 10 parts by weight of a photopolymerization initiator, (c) 5 to 30 parts by weight of a nonpolymerizable polymer, and (d) 1.0 to 10 parts by weight of a fine particle filler. (a) The radical polymerizable monomer has a refractive index of 1.45 to 1.57, (c) the non-polymerizable polymer has an average molecular weight of 2000 to 5000 g / mol, and (d) the fine particle filler has an average primary particle diameter of 0.001 to 1 μm, making it a dental curable composition for additive manufacturing. Furthermore, it is preferable that the dental curable composition for additive manufacturing increases the contrast ratio before and after curing. [Effects of the Invention]

[0007] The present invention provides a dental curable composition for additive manufacturing in which a non-polymerizable polymer and fine particle fillers are incorporated, resulting in a composition that is transparent before curing, becomes opaque after curing, and enhances light-shielding and white coloring effects. [Modes for carrying out the invention]

[0008] The dental curable composition for additive manufacturing of the present invention is a material for obtaining dental cured bodies using a 3D printer. The 3D printer used in the present invention is a 3D printer that performs additive manufacturing. Specifically, these are stereolithography (SLA, DLP) 3D printers.

[0009] Dental hardened materials refer to prosthetic devices, equipment, and instruments used inside and outside the oral cavity in dental treatment. Instruments and equipment include models, splints, dental models, splints, mouthguards, night guards, surgical guides, casting resin, trays, and the like. Prosthetic devices include inlays, onlays, crowns, bridges, dentures, and trial dentures. Trial dentures are the most preferred.

[0010] The component (a) radical polymerizable monomer used in the dental curable composition for additive manufacturing of the present invention is preferably one or more monofunctional or polyfunctional (meth)acrylates or a mixture thereof. A monofunctional (meth)acrylate means a compound having one radical polymerizable group, and a polyfunctional (meth)acrylate means a compound having two or more radical polymerizable groups.

[0011] Specific examples of monofunctional (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, propylene glycol mono(meth)acrylate, glycerol mono(meth)acrylate, erythritol mono(meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-bril (meth)acrylate, sec-butyl (meth)acrylate, Examples include t-butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, 2,3-dibromopropyl (meth)acrylate, 3-(meth)acryloyloxypropyltrimethoxysilane, 11-(meth)acryloyloxyundecyltrimethoxysilane, (3-phenoxyphenyl)methyl ester-2-(meth)acrylate ethoxylated o-phenylphenol (meth)acrylate, etc.

[0012] Examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, urethane di(meth)acrylate, 2,2-bis[4-(methacrylatexyethoxy)phenyl]propane, tricyclodecanedimethanol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, Examples include 2-hydroxy-1,3-dimethacryloxypropane, trimethylolpropane tri(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, propoxylated glyceryl tri(meth)acrylate, and propoxylated trimethylolpropane tri(meth)acrylate.

[0013] Monofunctional (meth)acrylates and polyfunctional (meth)acrylates may be used individually or in combination of two or more. These (a) radical polymerizable monomers serve as the base components on a weight basis.

[0014] The following compounds are examples of components (b) used as photopolymerization initiators in the dental curable composition for additive manufacturing of the present invention: acetophenone, 3'-hydroxyacetophenone, anthraquinone, sodium anthraquinone-2-sulfonate monohydrate, anisoin, p-anisyl, benzyl, benzoin, benzophenone, 2-benzoylbenzoic acid, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, benzoin methyl ether, benzoin isopropyl ether, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, Benzoin isobutyl ether, benzoin ethyl ether, methyl benzoyl formate, 4-benzoyl benzoic acid, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2-benzoyl methyl benzoate, 2-(1,3-benzodioxol-5-yl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-benzyl-2-(dimethylamino)-4'-morpholinobtyrophenone, (±) -Camphorquinone, 2-chlorothioxanthone, ferrocene, 4,4'-dihydroxybenzophenone, 4,4'-dichlorobenzophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, dibenzosverenone, 4,4'-dimethylbenzyl, 2,4-diethylthioxanthene-9-one, 4-(dimethylamino)benzophenone, 3,4-dimethylbenzophenone, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 1,4-dibenzoylbenzene, 2-ethylanthrate Quinone, 4'-hydroxyacetophenone, 4-hydroxybenzophenone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone, 3-hydroxybenzophenone, 2-isopropylthioxanthone, lithium phenyl (2,4,6-trimethylbenzoyl)phosphinate, 2-methylbenzophenone, 3-methylbenzophenone, 2-methyl-4'-(methylthio)-2-morpholinopropiophenone, 9,Examples include 10-phenanthrenequinone, 2-isonitrosopropiophenone, 4-phenylbenzophenone, 9,10-phenanthrenequinone, 2-phenyl-2-(p-toluenesulfonyloxy)acetophenone, and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, with diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide being preferred. Furthermore, the amount of component (b) of the present invention, the photopolymerization initiator, is 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight. More preferably 2 to 4 parts by weight.

[0015] The component (c) non-polymerizable polymer used in the dental curable composition for additive manufacturing of the present invention is a polymer that does not have polymerizable groups. The average molecular weight of the (c) non-polymerizable polymer is in the range of 2000 to 5000 g / mol, and is preferably 3000 to 5000 g / mol. (c)Specific examples of non-polymerizable polymers include polyethers. The most preferred (c)non-polymerizable polymer is polypropylene glycol. (a) The amount of (c) nonpolymerizable polymer blended with 100 parts by weight of radical polymerizable monomer is 5 to 30 parts by weight, preferred is 10 to 30 parts by weight, and more preferably 10 to 20 parts by weight. Furthermore, (c) when the non-polymerizable polymer is polypropylene glycol, the average molecular weight is preferably in the range of 2000 to 5000 g / mol, and more preferably in the range of 3000 to 5000 g / mol. The average molecular weight of polypropylene glycol is the value determined by gel permeation chromatography (GPC).

[0016] The component (d) fine particle filler according to the present invention may be any known fine particle filler used in dental materials without limitation. By incorporating the (d) fine particle filler, the composition has the effect of homogenizing and promoting improved transparency before and after curing. Specific examples of (d) fine particle fillers include silica, alumina, zirconia, other metal oxides, composite oxides thereof, and glass compositions. More preferably, silica, alumina, zirconia, and composite oxides thereof. The average primary particle diameter of the fine particle filler is 0.001 to 1 μm. If the primary particle diameter of the fine particle filler is less than 0.001 μm, it becomes difficult to incorporate it into the radical polymerizable monomer due to the increase in specific surface area. If the primary particle diameter of the particle filler exceeds 1 μm, sedimentation occurs in the composition, resulting in a decrease in the smoothness of the cured surface. The amount of component (d) fine particle filler of the present invention is 0.1 to 10 parts by weight, preferably 2.5 to 5 parts by weight. If the amount of (d) fine particle filler is less than 0.1 parts by weight, the improvement in transparency before and after curing will be small. If the amount of (d) fine particle filler exceeds 10 parts by weight, the transparency of the composition before curing will be impaired, the viscosity will increase, and additive manufacturing will become difficult.

[0017] The present invention can use known coloring agents used in dental materials. Either dyes or pigments can be used as coloring agents. Dyes are preferred. (a) The amount of coloring agent added per 100 parts by weight of radical polymerizable monomer is 0.001 to 1 part by weight. Specific examples of dyes include Brilliant Green, Ethyl Violet, Methyl Green, Crystal Violet, Basic Fuchsine, Methyl Violet 2B, Quinaldine Red, Rose Bengal, Methanyl Yellow, Thymol Sulfophthalein, Xylenol Blue, Methyl Orange, Paramethyl Red, Congo Red, Benzopurin 4B, α-Naphthyl Red, Nile Blue 2B, Nile Blue A, Methyl Violet, Malachide Green, Parafuchsine, Victoria Pure Blue BOH [manufactured by Hodogaya Chemical Co., Ltd.], OIL BLACK 803, OIL BLACK 860, OIL BLACK BS, OIL BLACK HBB, OIL BLACK NO5, OIL BLUE 2N, OIL BLUE 613, OIL BROWN BB, OIL GREEN 502, OIL GREEN 530, OIL ORANGE 201, OIL ORANGE PS, OIL PINK 312, OIL RED 330, OIL Examples include RED 5B, OIL RED OG, OIL RED RR, OIL SCARLET 308, OIL SCARLET 318, OIL YELLOW 105, OIL YELLOW 107, OIL YELLOW 129, OIL YELLOW 136, OIL YELLOW 3G, and OIL YELLOW GG-S [manufactured by Orient Chemical Co., Ltd.]. These dyes can be used individually or in combination.

[0018] When using pigments, care must be taken to prevent precipitation. Pigments are broadly classified into inorganic pigments and organic pigments. Examples of inorganic pigments include chromates such as lead yellow, lead zinc, and barium yellow; ferrocyanides such as Prussian blue; sulfides such as vermilion, cadmium yellow, zinc sulfide, antimony white, and cadmium red; sulfates such as barium sulfate, zinc sulfate, and strontium sulfate; oxides such as zinc oxide, titanium white, red iron oxide, iron black, and chromium oxide; hydroxides such as aluminum hydroxide; silicates such as calcium silicate and ultramarine; and carbon such as carbon black and graphite.

[0019] Examples of organic pigments include nitroso pigments such as naphthol green B and naphthol green Y; nitro pigments such as naphthol S and resorcin fast yellow 2G; insoluble azo pigments such as permanent red 4R, brilliant fast scarlet, hansa yellow, and benzidine yellow; poorly soluble azo pigments such as resorcin red, lake red C, and lake red D; soluble azo pigments such as brilliant carmine 6B, permanent red F5R, pigment scarlet 3B, and Bordeaux 10B; phthalocyanine pigments such as phthalocyanine blue, phthalocyanine green, and sky blue; basic dye-based pigments such as rhodamine lake, malachite green lake, and methyl violet lake; acidic dye-based pigments such as peacock blue lake, eosin lake, and quinoline yellow lake, etc. These pigments can be used alone or in combination of multiple.

Example

[0020] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to the following examples. Each component used in the examples or comparative examples will be described below together with abbreviations. Each component used in the examples and its abbreviation are as follows: (a) Radical polymerizable monomer: BPE-100: Ethoxylated bisphenol A dimethacrylate, refractive index 1.532 (Shin-Nakamura Chemical Co., Ltd.) [[ID=^{}14]] 3G: Triethylene glycol dimethacrylate, refractive index 1.459 (Shin-Nakamura Chemical Co., Ltd.) (b) Photoinitiator: TPO: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Tokyo Chemical Industry) (c) Non-polymerizable polymer: PPG400: Polypropylene glycol, average molecular weight 400 (Sigma-Aldrich) PPG2000: Polypropylene glycol, average molecular weight 2000 (Sigma-Aldrich) PPG2700: Polypropylene glycol, average molecular weight 2700 (Sigma-Aldrich) {{END]]PPG4000: Polypropylene glycol, average molecular weight 4000 (Sigma-Aldrich) (d) Particulate filler: SiO2: Aerosil R-972, average primary particle size 16nm (Aerosil Japan) SiO2: Aerosil OX-50, average primary particle size 16-40 nm (Aerosil Japan)

[0021] (Method for measuring the contrast ratio of dental hardening compositions for additive manufacturing) The prepared dental hardening composition for additive manufacturing was filled into a ring mold with a diameter of 15 mm and a thickness of 1 mm, which was placed on a transparent glass plate, and another transparent glass plate was placed on top to sandwich it. The colorimetric Y value was measured using a Konica Minolta CM-5 spectrophotometer under both white and black background conditions. The contrast ratio (contrast ratio = black background Y value / white background Y value) was calculated from the colorimetric Y value. The measurement result is referred to as the "contrast ratio of the composition."

[0022] (Method for measuring the contrast ratio of cured bodies of dental hardening compositions for additive manufacturing) Using an additive manufacturing system (DWP-80S: DGSHAPE), the prepared dental hardening composition for additive manufacturing was fabricated into test specimens with a diameter of 15 mm and a thickness of 1 mm. The colorimetric Y values ​​of these test specimens were measured against a white and black background using a spectrophotometer CM-5 (Konica Minolta). The contrast ratio (contrast ratio = black background Y value / white background Y value) was calculated from the colorimetric Y values. The measurement result is referred to as the "contrast ratio of the hardened material."

[0023] (Method for evaluating the increase in contrast ratio before and after curing) The contrast ratio before and after curing was evaluated using the following formula. (Increase in contrast ratio before and after curing) = (Contrast ratio of cured material) - (Contrast ratio of composition) Evaluation A: The increase in contrast ratio before and after curing is 0.41 or greater. Evaluation B: The increase in contrast ratio before and after curing was 0.31 to 0.40. Rating C: The increase in contrast ratio before and after curing was 0.21 to 0.30. Rating D: The increase in contrast ratio before and after curing was 0.11 to 0.20. Rating E: The increase in contrast ratio before and after curing was 0.06 to 0.10. Rating F: The increase in contrast ratio before and after curing is between 0 and 0.05.

[0024] (Method for measuring the bending strength of a composition) Using an additive manufacturing system (DWP-80S:DGSHAPE), the prepared dental hardening composition for additive manufacturing was fabricated into a 2.0 mm × 2.0 mm × 25 mm test specimen. This specimen was subjected to a three-point bending test using an Instron 5567 universal testing machine (manufactured by Instron) under the conditions of a crosshead speed of 1 mm / mm and a support distance of 20 mm. (Method for evaluating the rate of reduction in bending strength) The rate of reduction in bending strength was evaluated using the following formula. (Method for evaluating the rate of decrease in bending strength) = 1 - (Bending strength of the cured material) / (Bending strength of the cured material consisting only of component (a) and component (b)) Rating A: Bending strength reduction rate is 15% or less. Evaluation B: Bending strength reduction rate is 16% to 30%. Rating C: Bending strength reduction rate from 31% to 45%. Rating D: Bending strength reduction rate from 46% to 60%. Rating E: Bending strength reduction rate from 61% to 75%. Rating F: Bending strength reduction rate is 76% or more.

[0025] (Method for evaluating formability) Five test specimens with a thickness of φ15 × t1.0 mm were fabricated using a DWP-80S additive manufacturing system (DGSHAPE Corporation) with the prepared dental curing composition for additive manufacturing. The test specimens were fabricated under the condition of irradiation time of 10 seconds per layer. "A" indicates that all test pieces were successfully fabricated, "B" indicates that 3 to 4 pieces were successfully fabricated, and "C" indicates that 2 or fewer pieces were fabricated. [Table 1]

[0026] Overall evaluation result: As shown in Table 1, the examples using dental compositions within the following compositional ranges of the dental curable composition for additive manufacturing of the present invention showed an increase in the carbon ratio of the cured body and excellent moldability. The composition range of the dental curable composition for additive manufacturing of the present invention is as follows: (a) 100 parts by weight of radical polymerizable monomer, (b) 0.1 to 10 parts by weight of photopolymerization initiator, (c) 5 to 30 parts by weight of nonpolymerizable polymer, and (d) 1.0 to 10 parts by weight of fine particle filler. The radical polymerizable monomer has a refractive index of 1.45 to 1.57, the nonpolymerizable polymer has an average molecular weight of 2000 to 5000 g / mol, and the fine particle filler has an average primary particle diameter of 0.001 to 1 μm. On the other hand, in Comparative Examples 1 and 2, which were not within the composition range of the dental curable composition for additive manufacturing of the present invention, the amount of photopolymerization initiator was inappropriate, resulting in poor moldability. In Comparative Examples 3, 4, and 5, the average molecular weight or amount of the selected nonpolymerizable polymer was inappropriate, resulting in poor increase in the carbon ratio of the cured product and poor moldability. Comparative Example 6 did not contain a nonpolymerizable polymer, and the carbon ratio of the cured product did not increase. In Comparative Example 7, the viscosity increased, resulting in layering defects. In Comparative Example 8, the carbon ratio of the composition did not increase, and the moldability was also poor. [Industrial applicability]

[0027] It can be used in dental curable compositions for additive manufacturing in additive manufacturing equipment and can be used industrially.

Claims

1. (a) per 100 parts by weight of radical polymerizable monomer (b) 0.1 to 10 parts by weight of photopolymerization initiator, (c) 15 to 30 parts by weight of non-polymerizable polymer (d) Containing 1.0 to 10 parts by weight of particulate filler, (a) Radical polymerizable monomers have a refractive index of 1.45 to 1.57, (c) Non-polymerizable polymers have an average molecular weight of 2000 to 5000 g / mol. (d) The particulate filler has an average primary particle size of 0.001 to 1 μm. (c) The non-polymerizable polymer is a polyether. A dental curable composition for additive manufacturing, characterized by the following features.

2. (a) per 100 parts by weight of radical polymerizable monomer (b) The dental curable composition for additive manufacturing according to claim 1, comprising 1 to 5 parts by weight of a photopolymerization initiator.

3. (a) per 100 parts by weight of radical polymerizable monomer (b) The dental curable composition for additive manufacturing according to claim 1, comprising 2 to 4 parts by weight of a photopolymerization initiator.

4. (c) The nonpolymerizable polymer has an average molecular weight of 3000 to 5000 g / mol, as described in any one of claims 1 to 3, for use in dental additive manufacturing.

5. (a) per 100 parts by weight of radical polymerizable monomer (c) A dental curable composition for additive manufacturing according to any one of claims 1 to 4, comprising 15 to 20 parts by weight of a nonpolymerizable polymer.

6. (a) per 100 parts by weight of radical polymerizable monomer (d) A dental curable composition for additive manufacturing according to any one of claims 1 to 5, comprising 2.5 to 5 parts by weight of fine particle filler.

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