阅读说明：本技术 用于牙科用三维造型物的制作的牙科用光造型式三维印刷材料 (Dental stereolithography three-dimensional printing material for producing dental three-dimensional molded object ) 是由 丹羽菜实起 藤村英史 于 2020-03-26 设计创作，主要内容包括：本发明涉及牙科用光造型式三维印刷材料以及牙科用三维造型物的制造方法。本发明提供一种牙科用光造型式三维印刷材料,从使用3D打印机进行造型至最终固化为止的所需的制作时间短且作业效率性优异,并且牙科用三维造型物的经时收缩变形得到抑制且尺寸精度优异。牙科用光造型式三维印刷材料包含：至少一种以上的具有芳香环的单官能丙烯酸酯单体(a)；以及光聚合引发剂(b),在构成具有芳香环的单官能丙烯酸酯单体(a)的全部原子中,以共价键相邻的原子间的电负性差小于1.0。(The present invention relates to a dental stereolithography material and a method for producing a dental three-dimensional molded object. The invention provides a dental optical three-dimensional printing material, which has short production time required from modeling to final curing by using a 3D printer, excellent operation efficiency, suppressed time-lapse shrinkage deformation of a dental three-dimensional modeling object and excellent dimensional accuracy. The dental stereolithography material comprises: at least one or more monofunctional acrylate monomers (a) having an aromatic ring; and a photopolymerization initiator (b) in which the difference in electronegativity between atoms adjacent to each other by covalent bonds among all atoms constituting the monofunctional acrylate monomer (a) having an aromatic ring is less than 1.0.)

1. A dental light-modeling three-dimensional printing material is characterized in that,

comprises the following steps: at least one or more monofunctional acrylate monomers (a) having an aromatic ring; and a photopolymerization initiator (b),

the difference in electronegativity between atoms adjacent in a covalent bond among all atoms constituting the monofunctional acrylate monomer having an aromatic ring (a) is less than 1.0.

2. The dental phototype three-dimensional printing material of claim 1,

contains 0.1 to 5 wt% of the photopolymerization initiator (b).

3. The dental phototype three-dimensional printing material of claim 1,

further comprising a polyfunctional methacrylate monomer (c) having an electronegativity difference between atoms adjacent to each other by covalent bonds among all the constituent atoms of less than 1.0 and satisfying the following formula (I),

molecular weight/molecular length when both ends of a monomer molecule are methacrylate groups < 20.0 … formula (I)

The unit of the molecular length is angstroms.

4. The dental prosthetic-type three-dimensional printing material according to claim 3,

the composition comprises 10-70 wt% of the monofunctional acrylate monomer having an aromatic ring (a), 0.1-5 wt% of the photopolymerization initiator (b) and 25-89.9 wt% of the multifunctional methacrylate monomer (c) relative to the total weight of the monofunctional acrylate monomer having an aromatic ring (a), the photopolymerization initiator (b) and the multifunctional methacrylate monomer (c).

5. The dental optically patterned three-dimensional printing material according to any one of claims 1 to 4,

comprises the following steps: one or more of a non-dendrimer, an inorganic filler and a coloring material, which do not contain an inorganic atom in the structure.

6. The dental optically patterned three-dimensional printing material according to any one of claims 1 to 5,

a viscosity at 23 ℃ of 1 or more and less than 3000 in mPas.

7. A method for manufacturing a dental three-dimensional shaped object,

a dental three-dimensional shaped object which is shaped by a stereolithography printer using the dental stereolithography material according to any one of claims 1 to 6, does not require final curing by an optical and/or heat type post-curing device.

Technical Field

The present invention relates to a dental stereolithography material and a method for producing a dental three-dimensional molded object using the same.

Background

In recent years, with the rapid spread of three-dimensional CAD, a print modeling technique using a 3D printer has been adopted in many industrial fields. In the print modeling technique using a 3D printer, the photo-modeling method is a method of producing a three-dimensional modeled object by laminating and curing a photo-curable resin (hereinafter, also referred to as a photo-modeling three-dimensional printed material or a three-dimensional printed material) by ultraviolet rays and/or visible light based on three-dimensional CAD data. By the spread of such a printing and modeling technique, products can be produced in a simple, rapid, and mass manner.

In the aforementioned printing and molding technology of the stereolithography system, many proposals have been made regarding stereolithography-type three-dimensional printed materials aimed at further improving the work efficiency, molding accuracy, and mechanical properties. For example, jp 2018-76455 a discloses a printing material that contains a specific cationically polymerizable compound and a specific radically polymerizable compound, and that can produce a molded article having a small warpage change rate and excellent heat resistance and strength in a short molding time.

In the dental field, the availability of print modeling techniques is also high. Conventionally, an impression material is used to take an impression of the oral cavity shape of a patient, and the cured model is managed as real data for reproducing the oral cavity shape. However, in recent years, an intraoral optical scanner has been widely used, and the intraoral shape of a patient is read by the scanner, so that the intraoral shape can be digitally managed as three-dimensional CAD data.

Under such circumstances, proposals have been recently made in the field of dental materials as well as in the field of stereolithography.

For example, Japanese patent application laid-open No. 2016 & 525150 discloses a liquid resin composition that enables a dental bed and an artificial tooth to be easily and simply produced by using a 3D printer of a stereolithography system.

Disclosure of Invention

The dental patch device manufactured by using the printing and molding technique of the optical molding method is generally manufactured in the order of "molding by a 3D printer → washing of a three-dimensional shaped object → final curing of the three-dimensional shaped object by an optical and/or thermal post-curing device".

In the conventional stereolithographic three-dimensional printing material, since the polymerization degree in the modeling step by the 3D printer is low, the polymerization shrinkage at the time of final curing by the post-curing device is large, and thus, there is a problem that deformation occurs, and it is difficult to match the final cured product with desired data.

In particular, since the dental prosthetic device requires precise accuracy for matching with each patient, it is necessary that the dental prosthetic device is not deformed and must conform to desired data in the oral cavity of the patient.

An object of the present invention is to provide a dental stereolithography-type three-dimensional printed material which has a short total production time for a dental three-dimensional shaped object produced by a 3D printer, achieves a high degree of polymerization in a shaping step, suppresses deformation of the dental three-dimensional shaped object with time, and has excellent dimensional accuracy.

The present invention provides a dental optical three-dimensional printing material, comprising: at least one or more monofunctional acrylate monomers (a) having an aromatic ring; and a photopolymerization initiator (b) having an electronegativity difference of less than 1.0 between atoms adjacent to each other by covalent bonds among all atoms constituting the monofunctional acrylate monomer (a) having an aromatic ring.

In the present invention, it is preferable that the photopolymerization initiator (b) is contained in an amount of 0.1 to 5 wt% based on the total weight of the monofunctional acrylate monomer (a) having an aromatic ring and the photopolymerization initiator (b).

In the present invention, it is preferable that the multifunctional methacrylate monomer (c) further contains a polyfunctional methacrylate monomer having an electronegativity difference between atoms adjacent to each other by covalent bonds of less than 1.0 among all the atoms constituting the multifunctional methacrylate monomer (c) and satisfying the following formula (I).

Molecular weight/molecular length (Angstrom) when both ends of a monomer molecule are methacrylate groups < 20.0 … formula (I)

In this case, it is preferable that the monofunctional acrylate monomer (a) having an aromatic ring, the photopolymerization initiator (b) and the polyfunctional methacrylate monomer (c) are contained in an amount of 10 to 70 wt%, 0.1 to 5 wt% and 25 to 89.9 wt%, based on the total weight of the monofunctional acrylate monomer (a), the photopolymerization initiator (b) and the polyfunctional methacrylate monomer (c).

In the present invention, the dental light-induced pattern three-dimensional printed material preferably further comprises: one or more of a non-dendrimer, an inorganic filler and a coloring material, which do not contain an inorganic atom in the structure.

In the present invention, the dental optical three-dimensional printing material preferably has a viscosity (mPa · s) at 23 ℃ of 1 or more and less than 3000.

The invention provides a method for manufacturing a dental three-dimensional object, which uses the dental light-producing three-dimensional printing material and performs modeling by using the recommended conditions of any light-producing three-dimensional printer without final curing by light and/or a heating type post-curing device.

The present invention can provide a dental stereolithography-type three-dimensional printing material which requires a short production time from the time of molding by a 3D printer to the time of final curing, has excellent work efficiency, is less likely to cause deformation of a dental three-dimensional molded object with time, and has excellent dimensional accuracy.

Detailed Description

The numerical range indicated by "-" in the present specification means a range including the numerical values described before and after "-" as the lower limit value and the upper limit value.

The "dental stereolithography-type three-dimensional printing material" of the present invention is a material for producing a three-dimensional shaped object for dental use (hereinafter, also referred to as "dental three-dimensional shaped object") by a stereolithography-type printing mechanism.

The "three-dimensional shaped object used in dentistry" refers to devices, equipments, or appliances used inside and outside the oral cavity in dentistry, and specifically includes a patch device, an orthotic device, a model, a splint (spline), a molar guard (mouthguard), a night guard (night guard), a surgical guide (surgical guide), and a molded object for casting. The "prosthetic device" is an artificial structure that replaces natural teeth, and specifically includes inlays, onlays, crowns, bridges, dentures, and the like.

Among these, the dental stereolithography-type three-dimensional printing material of the present invention is preferably used for producing a model, a splint, a tooth protector, a night guard, a surgical guide, and a mold.

The "printing mechanism of the stereolithography type" is a three-dimensional modeling method using a 3D printer using ultraviolet rays and/or visible Light as a Light source, and specifically includes an sla (stereo Lithography) system, a DLP (Digital Light Processing) system, an inkjet system, and the like.

The "SLA method" is a method of obtaining a three-dimensional shaped object by irradiating a three-dimensional printed material with a spot laser beam.

When a dental three-dimensional object is produced by the SLA method, for example, the three-dimensional printed material of the present invention is stored in a tank, and a spot-shaped laser beam is selectively irradiated onto the liquid surface of the three-dimensional printed material to cure the three-dimensional printed material, thereby forming a cured layer having a desired thickness on a modeling table so as to obtain a desired shape. Next, the modeling table is lowered, and one layer of uncured three-dimensional printing material is supplied onto the cured layer and cured in the same manner to obtain a continuous cured layer, and the laminating operation is repeated. Thereby, a dental three-dimensional shaped object can be produced.

The "DLP system" is a system in which a three-dimensional object is obtained by irradiating planar light to a three-dimensional printed material.

When a dental three-dimensional object is produced by the DLP method, for example, the three-dimensional printed material of the present invention is stored in a tank, and a planar light is selectively irradiated from the bottom surface of the tank to cure the three-dimensional printed material, so that a cured layer having a desired thickness is formed on a modeling table to obtain a desired shape. Next, the modeling table is lifted, and one layer of uncured three-dimensional printing material is supplied under the cured layer, and similarly cured to obtain a continuous cured layer, and the stacking operation is repeated. Thereby, a dental three-dimensional shaped object can be produced.

The "ink jet system" is a system in which droplets of a three-dimensional printed material are continuously ejected from an ink jet nozzle toward a base material, and the droplets adhering to the base material are irradiated with light to obtain a three-dimensional object.

In the case of producing a dental three-dimensional object by an ink jet method, for example, while scanning a head including an ink jet nozzle and a light source in a plane, a three-dimensional printing material is ejected from the ink jet nozzle toward a base material, and the ejected three-dimensional printing material is irradiated with light to form a cured layer. These operations are repeated, and the cured layers are sequentially laminated. Thereby, a dental three-dimensional shaped object can be produced.

The dental-use three-dimensional printing material of the present invention preferably has a viscosity of 1(mPa · s) or more and less than 3000(mPa · s) at 23 ℃.

The "monofunctional acrylate monomer (a) having an aromatic ring" of the present invention is a monomer containing only one acrylate group, and has an aromatic ring within the structure of the monomer.

The "aromatic ring" is preferably a benzene ring. The aromatic ring may be located at any part of the structure, preferably having a benzene ring at the end.

In particular, in the "monofunctional acrylate monomer (a) having an aromatic ring" of the present invention, the difference in electronegativity between atoms adjacent to each other by covalent bonds among all atoms constituting the monofunctional acrylate monomer (a) having an aromatic ring is less than 1.0.

The "covalent bond" in the present invention is a chemical bond formed with a pair of electrons shared between atoms, and does not include intermolecular forces such as hydrogen bond, coulomb force, dipole interaction, and van der waals force.

The "electronegativity" of the present invention is a scale that relatively represents the intensity with which an atom within a molecule attracts electrons. The electronegativity of the present invention is according to the electronegativity of the state transition process (poling).

When the electronegativity difference between atoms adjacent to each other by covalent bonds is 1.0 or more, molding failure is likely to occur when photo-molding is performed under the same conditions as in the case of less than 1.0, and as a result, it is necessary to extend the molding time or heat the material, which leads to a decrease in molding efficiency.

The "molding failure" means insufficient curing of the three-dimensional printing material, and specifically includes: the molder is not made; the object is not formed into the desired shape; the line of lamination on the surface of the shaped object is unclear.

Specific examples of the "monofunctional acrylate monomer (a) having an aromatic ring" of the present invention include ethoxylated o-phenylphenol acrylate (A-PP-EO), phenoxy diethylene glycol acrylate (A-P2EG), phenoxy polyethylene glycol acrylate, 3-phenoxy benzyl acrylate (A-PB), phenoxy ethyl acrylate (A-PE), and neopentyl glycol-acrylic acid-benzoate.

The three-dimensional printing material of the present invention may contain only one "monofunctional acrylate monomer (a) having an aromatic ring", or may contain two or more "monofunctional acrylate monomers (a) having an aromatic ring".

The content (total content in the case of two or more types) of the "monofunctional acrylate monomer (a)" having an aromatic ring in the three-dimensional printing material of the present invention is preferably from 1 to 99.9% by weight based on the total weight of the "monofunctional acrylate monomer (a) having an aromatic ring and the photopolymerization initiator (b), or from 1 to 99.9% by weight based on the total weight of the" monofunctional acrylate monomer (a) having an aromatic ring ", the photopolymerization initiator (b) and the polyfunctional methacrylate monomer (c) when the" polyfunctional methacrylate monomer (c) "described later is contained, from 10 to 70% by weight from the viewpoint of the strength of the molded article for dental use produced by the present invention.

The "photopolymerization initiator (b)" of the present invention refers to a polymerization initiator that absorbs light of a wavelength generally used in a photo-modeling 3D printer and generates radicals. Specifically, it is a polymerization initiator having an absorption band in the wavelength region of 350-450 nm.

Examples of the "photopolymerization initiator (b)" in the present invention include an alkylphenone-based compound, an acylphosphine oxide-based compound, a titanocene (titanocene) -based compound, an oxime ester-based compound, a benzoin-based compound, an acetophenone-based compound, a benzophenone-based compound, a thioxanthone-based compound, a benzyl-based compound, a diphenylsulfide-based compound, and an anthraquinone-based compound.

Among these, acylphosphine oxide compounds are preferable from the viewpoint of reactivity and the like. Examples of the acylphosphine oxide-based compound include bis (2, 4, 6-trimethylbenzoyl) -phenylphosphine oxide, 2, 4, 6-trimethylbenzoyl-diphenyl-phosphine oxide (MAPO), and the like.

The three-dimensional printing material of the present invention may contain only one kind of photopolymerization initiator (b), or may contain two or more kinds of photopolymerization initiators (b).

The content (total content in the case of two or more types) of the photopolymerization initiator (b) in the three-dimensional printing material of the present invention is preferably 0.1 to 5 wt% based on the total weight of the "monofunctional acrylate monomer (a) having an aromatic ring" and the photopolymerization initiator (b), or when the "polyfunctional methacrylate monomer (c)" described later is included, preferably 0.1 to 5 wt% based on the total weight of the "monofunctional acrylate monomer (a) having an aromatic ring", the photopolymerization initiator (b), and the polyfunctional methacrylate monomer (c). When the content of the photopolymerization initiator (b) is less than 0.1 wt%, molding defects (e.g., a decrease in dimensional accuracy of a molded article, a decrease in adsorbability between the molded article and a molding table) due to insufficient curing may occur even if the exposure time per layer is set to the upper limit. When the content of the photopolymerization initiator (b) exceeds 5 wt%, there may be a case where molding defects (such as a decrease in dimensional accuracy of a molded article and a decrease in mold releasability between a molded article and a groove) or color tone defects are caused by excessive curing even if the exposure time per layer is set to the upper limit.

The three-dimensional printing material of the present invention may contain a polyfunctional methacrylate monomer (c) having an electronegativity difference between atoms adjacent to each other by covalent bonds of less than 1.0 among all atoms constituting the monomer and conforming to formula (I).

Molecular weight/molecular length (Angstrom) when both ends of a monomer molecule are methacrylate groups < 20.0 … formula (I)

The "multifunctional methacrylate monomer (c)" of the present invention is a monomer containing two or more methacrylate groups. By including the "multifunctional methacrylate monomer (c)", a suitable strength can be obtained as a dental three-dimensional molded article.

The "molecular length (angstrom) when both ends of a monomer molecule are methacrylate groups" in the present invention is calculated from the average bonding distance between atoms covalently bonded in the molecule.

If the formula (I) is 20.0 or more, molding failure is likely to occur when the photo-molding is performed under the same conditions as in the case of less than 20.0, and as a result, it is necessary to extend the molding time or heat the material, which leads to a decrease in molding efficiency.

Specific examples of the "multifunctional methacrylate monomer (c)" in the present invention include bisphenol a dimethacrylate, Urethane Dimethacrylate (UDMA), ethoxylated bisphenol a dimethacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate (2M-3EG), tetraethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, hexanediol dimethacrylate, neopentyl glycol dimethacrylate, polypropylene glycol dimethacrylate, and ethoxylated polypropylene glycol dimethacrylate.

The three-dimensional printing material of the present invention may contain only one kind of polyfunctional methacrylate monomer (c), or may contain two or more kinds of polyfunctional methacrylate monomers (c).

The content (total content in the case of two or more types) of the polyfunctional methacrylate monomer (c) in the three-dimensional printing material of the present invention is preferably from 0 to 89.9% by weight based on the total weight of the monofunctional acrylate monomer (a) having an aromatic ring, the photopolymerization initiator (b), and the polyfunctional methacrylate monomer (c), and from the viewpoint of the strength of the molded article for dental use produced by the present invention, the content is preferably from 25 to 89.9% by weight.

The three-dimensional printed material of the present invention may contain, as necessary: the structure of the polymer contains no inorganic atoms, inorganic filler and coloring material.

The "non-dendrimer having no inorganic atom in the structure" in the present invention means an organic polymer having no inorganic atom in the structure and not participating in polymerization.

Examples thereof include polymethyl methacrylate, styrene-butadiene copolymer, acrylonitrile-styrene-butadiene copolymer, polyether ether ketone, polybutadiene, polyethylene terephthalate, polyvinyl chloride, poly (bisphenol a carbonate), polyethylene glycol, methoxypolyethylene glycol amine, poly (ethylene glycol) methyl ether, poly (ethylene glycol) dimethyl ether, poly (ethylene glycol) bis (carboxymethyl) ether, poly (ethylene glycol) bis (amine), poly (ethylene glycol) divinyl ether, O- (2-aminoethyl) polyethylene glycol, polypropylene glycol, polylactic acid-glycolic acid copolymer, polyglycolic acid, polylactic acid, polydioxanone, and poly (1, 4-phenylene sulfide).

The three-dimensional printing material of the present invention may contain only one kind of non-dendrimer having no inorganic atom in the structure, or may contain two or more kinds of non-dendrimers having no inorganic atom in the structure.

Examples of the "inorganic filler" of the present invention include transition metals of groups I, II, III and IV of the periodic Table, oxides thereof, silicic acid, and mixtures thereof.

Specific examples thereof include glass powders such as silicon dioxide (silica) powder, alumina powder (alumina powder), zirconia powder, lanthanum glass powder, barium glass powder, and strontium glass powder, quartz powder, titanium oxide powder, glass beads, glass fibers, barium fluoride powder, silica gel powder, colloidal silica, and zirconium oxide powder.

The average particle diameter of the inorganic filler is required to be smaller than the stacking height of each layer in the molding, and is preferably 0.001 to 50 μm, more preferably 0.001 to 5 μm.

The inorganic filler is preferably surface-treated with a silane coupling agent from the viewpoint of improving dispersibility in the three-dimensional printing material.

The silane coupling agent includes an acryl silyl group, a methacryl silyl group, an epoxy silyl group, a methyl silyl group, a dimethyl silyl group, a trimethyl silyl group, a methoxy silyl group, a dimethoxy silyl group, a trimethoxy silyl group, an ethoxy silyl group, a diethoxy silyl group, a triethoxy silyl group, an alkyl silyl group, a diphenyl silyl group, a vinyl silyl group, a styryl silyl group, an organic silyl group, a dimethyl polysiloxane group, a hexamethyldisilazane group, an amino alkylsilyl group, and one or more of these groups can be used.

The three-dimensional printing material of the present invention may contain only one kind of inorganic filler, or may contain two or more kinds of inorganic fillers.

The "coloring material" of the present invention is not limited as long as it does not interfere with the molding by the photo-molding 3D printer and is hard to change color, and examples thereof include inorganic pigments, oil-soluble dyes, and pigments.

The three-dimensional printed material of the present invention may contain only one kind of coloring material, or may contain two or more kinds of coloring materials.

In the three-dimensional printing material of the present invention, when the total weight of the "monofunctional acrylate monomer having an aromatic ring (a)" and the photopolymerization initiator (b) is 100 parts by weight or when the "multifunctional methacrylate monomer (c)" is contained, the total weight of the "monofunctional acrylate monomer having an aromatic ring (a)", the photopolymerization initiator (b), and the "multifunctional methacrylate monomer (c)" is 100 parts by weight, the total weight of the non-dendrimer, the inorganic filler, and the coloring material, which do not contain an inorganic atom in the structure, is 50 parts by weight or less, preferably 20 parts by weight or less. If the amount exceeds 50 parts by weight, molding defects may occur due to thickening.

The present invention may include other monomers than the "monofunctional acrylate monomer (a) having an aromatic ring" and the "multifunctional methacrylate monomer (c)". In this case, the content of the other monomer is preferably less than that of the "monofunctional acrylate monomer (a) having an aromatic ring", and in the case of including the "multifunctional methacrylate monomer (c)", it is preferably less than that of the "multifunctional methacrylate monomer (c)". Specifically, the amount of the other monomer is 30 parts by weight or less, preferably 20 parts by weight or less, and more preferably 10 parts by weight or less. In addition, it is preferable that the present invention does not contain monomers other than the "monofunctional acrylate monomer (a) having an aromatic ring" and the "multifunctional methacrylate monomer (c)".

In the method for producing a dental three-dimensional shaped object according to the present invention, the dental three-dimensional shaped object can be produced by using the dental stereolithography-type three-dimensional printing material according to the present invention and performing the shaping based on the recommended conditions of an arbitrary stereolithography-type three-dimensional printer, and therefore, final curing by a light and/or heat type post-curing device can be omitted.

The "optical and/or thermal post-curing apparatus" of the present invention refers to an apparatus or an apparatus for post-polymerizing a dental three-dimensional object molded by an arbitrary optical three-dimensional printer by ultraviolet rays and/or visible light and/or heat.