TW202336048A - Photocurable resin composition, cured object, three-dimensional shaped object, and method for producing casting mold - Google Patents

Abstract

The present invention provides a photocurable resin composition characterized by comprising a photopolymerization initiator (A) and a polyfunctional (meth)acrylate (B), wherein the amount of the photopolymerization initiator (A) is in the range of 10-30 parts by mass, excluding 10 parts by mass, per 100 parts by mass of the polyfunctional (meth)acrylate (B). The photopolymerization initiator (A) may at least comprise a first photopolymerization initiator (A-1), which has at least one maximal-absorption wavelength in a wavelength range of 350 nm and longer, and a second photopolymerization initiator (A-2), which has no maximal-absorption wavelength in the wavelength range of 350 nm and longer and has a maximal-absorption wavelength in a wavelength range below 350 nm. A three-dimensional shaped object comprising a cured object obtained by curing the photocurable resin composition has a high hardness and is excellent in terms of eliminability by high-temperature heating, shaping accuracy, and casting property.

Description

Photocurable resin composition, cured product, three-dimensional molded object, manufacturing method of casting mold, and method of manufacturing metal casting

The present invention relates to a method of manufacturing a photocurable resin composition, a cured product, a three-dimensional molded object, and a casting mold.

When manufacturing formed products of metal materials, methods such as machining or casting are usually used. Among them, the casting method can produce metal parts or metal products with complex shapes. As the casting method, a dewaxing method is known. In the dewaxing method, a prototype model of a cast object is made with wax or resin and embedded in an investment material. After the investment material hardens, the prototype model is The investment material is heated, whereby the prototype model is melted, decomposed or incinerated to remove, thereby forming a void in the investment material, and the void is used as a mold to inject molten metal and cast. The lost wax method is used in the fields of jewelry and dental technology.

In recent years, it has been proposed to use a three-dimensional (3D) printer to form a prototype model using a dewaxing method using a photocurable resin composition (Patent Document 1). [Prior art documents] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2018-048312

[Problem to be solved by the invention] However, conventional photocurable resin compositions have problems such as slow curing speed when irradiated with light, making molding difficult, or too fast curing speed, so even a small amount of light exposure causes curing, making handling difficult, and molding accuracy decreases. Furthermore, prototype models formed from this composition have problems such as the inability to maintain shape due to low hardness, insufficient disappearing properties when heated at high temperatures, residues such as dust remaining in the investment material, surface deterioration of the cast product, or problems due to The difference in expansion coefficient between the prototype model and the investment material causes cracks or ruptures in the investment material.

An object of the present invention is to provide a photocurable resin composition with excellent molding accuracy, and a molded article with high hardness, excellent disappearing properties when heated at high temperatures, and excellent castability.

In this specification, "excellent castability" refers to a state in which, when the molded object of the present invention is used as a prototype model to produce a mold, there are no cracks or cracks on the outside and inside of the mold, and there is no three-dimensional molding inside the mold. Residues and dust of the object are removed, and the transferability of the three-dimensional molded object to the mold is good. [Means to solve the problem]

In response to these problems, the present inventors discovered that a photocurable resin composition has a moderately fast curing speed and excellent molding accuracy, and that a molded object obtained by curing the resin composition has high hardness and has good disappearing properties when heated at high temperatures. and excellent castability, the present invention was completed. The photocurable resin composition is characterized by containing a photopolymerization initiator (A) and a polyfunctional (meth)acrylate (B). 100 parts by mass of methacrylate (B) and the content of the photopolymerization initiator (A) are in the range of more than 10 parts by mass to 30 parts by mass.

That is, the present invention includes the following aspects. (1) A photocurable resin composition characterized by containing a photopolymerization initiator (A) and a polyfunctional (meth)acrylate (B), with respect to the polyfunctional (meth)acrylate (B) 100 parts by mass, the content of the photopolymerization initiator (A) is in the range of more than 10 parts by mass to 30 parts by mass. (2) The photocurable resin composition according to (1), wherein the photopolymerization initiator (A) contains at least a first photopolymerizable compound having at least one maximum absorption wavelength in a wavelength range of 350 nm or more. An initiator (A-1), and a second photopolymerization initiator (A-2) that does not have a maximum absorption wavelength in a wavelength range of 350 nm or more and has a maximum absorption wavelength in a wavelength range of less than 350 nm. (3) The photocurable resin composition as described in (2), wherein the first photopolymerization initiator (A-1) is selected from the group consisting of free hydroxyl phosphine oxide, bis hydroxyl phosphine oxide, and titanium oxide. At least one of the group consisting of compounds, O-acyl oxime compounds and thioxanthone compounds. (4) The photocurable resin composition according to (2) or (3), wherein the second photopolymerization initiator (A-2) is selected from the group consisting of phenylalkyl ketone compounds and α-diketones. At least one from the group consisting of compounds and iodonium salts. (5) The photocurable resin composition according to any one of (2) to (4), wherein the second photopolymerization initiator (A-2) is smaller than the first photopolymerization initiator (A-2). The compounding ratio of the starting agent (A-1) [(A-1)/(A-2)] is in the range of 1/100 to 8/10. (6) The photocurable resin composition according to any one of (1) to (5), wherein the polyfunctional (meth)acrylate (B) contains at least one polyfunctional (meth)acrylate having a poly(meth)acrylate in the molecule and a structure. Oxyalkyl compounds. (7) The photocurable resin composition according to (6), wherein the polyfunctional (meth)acrylate (B) contains at least a compound having a polyoxyalkylene group and a bisphenol structure in the molecule ( B-1), the compound (B-1) is modified bisphenol A di(meth)acrylate, which has the following formula (I): [Chemical 1] represents, and R ¹ represents a hydrogen atom or a methyl group, multiple R ¹ in the same molecule may be the same or different, m and n each independently represent an integer of 1 or more, and m+n is 2 to 40. (8) The photocurable resin composition according to (6) or (7), wherein the polyfunctional (meth)acrylate (B) further contains one or more (meth)acrylates in the molecule acyl compound (B-2). (9) The photocurable resin composition according to (8), wherein the compound (B-1) is added in an amount of 40 parts per 100 parts by mass of the polyfunctional (meth)acrylate (B). Parts by mass ~ 90 parts by mass. (10) The photocurable resin composition according to any one of (1) to (9), further containing a non-metallic organic pigment (C). (11) The photocurable resin composition according to any one of (1) to (10) is used for stereolithography. (12) A cured product obtained by photocuring the photocurable resin composition according to any one of (1) to (11). (13) A three-dimensional shaped object including the hardened object according to (12). (14) A method of manufacturing a casting mold, characterized by comprising: step (1), using an embedding material to embed part or all of the three-dimensional shaped object as described in (13); step (2), embed the three-dimensional shaped object Hardening or solidifying the material; and step (3), removing the three-dimensional shaped object by melting, decomposing and/or incineration. (15) A method of manufacturing a metal casting, characterized by including the step (4) of flowing the metal material into the casting mold obtained by the manufacturing method as described in (14) and causing the metal material to flow into the mold. The metal material solidifies. [Effects of the invention]

According to the present invention, it is possible to provide a photocurable resin composition with excellent molding accuracy, and a molded article with high hardness, evaporability when heated at high temperatures, and excellent castability. Therefore, when making the casting mold, it is easy to shape the prototype model, the shape of the prototype model can be maintained, and residues when the prototype model is heated can be reduced, thereby preventing the casting mold from cracking or breaking.

Several embodiments of the present invention are described in detail below. However, the present invention is not limited to the following embodiments. In addition, the mass % in this specification from now on means the ratio when the whole photocurable resin composition is 100 mass %. In the present invention, the so-called "(meth)acrylate" refers to one or both of acrylate and methacrylate, and the so-called "(meth)acrylyl" refers to acrylate and methacrylate. One or both of the acyl groups.

[(A) Ingredient] The photopolymerization initiator (A) used in the present invention (also referred to as component (A) in this specification) is any chemical that generates free radicals, cations, or anions by irradiation with ultraviolet rays, electron beams, etc. It suffices to use one or a mixture thereof, and there is no particular limitation within the range in which the effects of the present invention can be obtained.

Furthermore, the content of the photopolymerization initiator (A) in the present invention is preferably in the range of 3 to 50 parts by mass, and more preferably 5 parts by mass relative to 100 parts by mass of the polyfunctional (meth)acrylate (B). The range of parts by mass to 40 parts by mass is preferably more than 10 parts by mass and 30 parts by mass or less. By setting these ranges, the molding accuracy can be improved by suitably accelerating the hardening speed, and the disappearing properties can be improved while suppressing expansion during high-temperature heating. Therefore, three-dimensional molding is easy, cracks or breaks during mold formation are prevented, dust residues are reduced, and castability is excellent.

In the present invention, the photopolymerization initiator (A) preferably contains the first photopolymerization initiator (A-1) having at least one maximum absorption wavelength in the wavelength range above 350 nm. Thereby, it has excellent reactivity with (meth)acrylate compounds when irradiated with ultraviolet rays (especially light with wavelengths around 350 nm to 450 nm), the curing speed is accelerated, and the molding accuracy becomes good. Therefore, three-dimensional modeling is easy.

As the first photopolymerization initiator (A-1), it is preferably selected from the group consisting of hydroxyl phosphine oxide, bis hydroxyl phosphine oxide, titanocene compound, O-hydroxyl oxime compound and thioxanthone compound. At least one of the groups, specifically, examples include: 2,4,6-trimethylbenzyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzyldiphenyl) Phenylphosphine oxide, bis(2,4-cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrrolyl)phenyl]titanium(IV), 1-[4-(phenylsulfide) Base) phenyl]octane-1,2-dione=2-(O-benzyl oxime), 2,4-diethylthioxanthone, etc. Among these, they are excellent in reactivity with (meth)acrylate compounds and can reduce dust residue during baking compared to compounds with large molecular weights and complex structures or compounds containing metal atoms in the molecule. In other words, a phosphorus compound is preferred. Specifically, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyldiphenylphosphine oxide) are preferred. Phenylphosphine oxide. In addition, these compounds may be used individually or in combination of 2 or more types.

The photopolymerization initiator (A) preferably further contains a second photopolymerization initiator (A- 2). The second photopolymerization initiator (A-2) also remains in an unreacted state after being irradiated with ultraviolet rays (especially light with wavelengths around 350 nm to 450 nm) and remains in the molded object in large amounts. Therefore, it is considered that radicals, cations, or anions are generated when the molded article is heated and react with the unreacted (meth)acrylate compound to partially harden the molded article. Therefore, by blending the second photopolymerization initiator (A-2), expansion during high-temperature heating can be suppressed, and cracks or breaks in the mold can be prevented when the mold is produced. That is, the castability is excellent.

The second photopolymerization initiator (A-2) is preferably at least one selected from the group consisting of phenylalkyl ketone compounds, α-diketone compounds, and ion salts. Specifically, it can be Examples: 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy -2-Methyl-1-propan-1-one, 2,2-dimethoxy-2-phenylacetophenone, 2-hydroxy-1-(4-(4-(2-hydroxy-2- Methylpropynyl)benzyl)phenyl)-2-methylpropan-1-one, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropane-1 -Ketone, 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)-1-butanone, 2-dimethylamino-2-(4-methylbenzyl) )-1-(4-morpholin-4-yl-phenyl)-butan-1-one, methyl benzylcarboxylate, bis(2-phenyl-2-oxoacetic acid)oxybis Ethylene and commercially available ion salt (for example, trade name "Omnicat 250", manufactured by IGM). Among these, 1-hydroxycyclohexylphenyl ketone and 2-methyl-1-[4-(methylthio)phenyl are more preferred from the viewpoint of ease of acquisition and improvement in disappearing property when heated at high temperatures. ]-2-morpholinylpropan-1-one, 2,2-dimethoxy-2-phenylacetophenone. In addition, these compounds may be used individually or in combination of 2 or more types.

From the above, the addition of the first photopolymerization initiator (A-1) can accelerate the hardening speed, and the addition of the second photopolymerization initiator (A-2) can suppress expansion of the molded article during high-temperature heating. Furthermore, the first photopolymerization initiator (A-1) and the second photopolymerization initiator (A-2) also contribute to improving the disappearing property during high-temperature heating. On the other hand, when the blending amount of the first photopolymerization initiator (A-1) is too high, problems such as a decrease in molding accuracy due to excessive curing speed may occur. Therefore, it is preferable that the second photopolymerization initiator (A-2) has a relative ratio of The blending ratio [(A-1)/(A-2)] of the first photopolymerization initiator (A-1) is preferably in the range of 1/100 to 1/1, more preferably 1/100 to 9 /10 range, particularly preferably in the range of 1/100 to 8/10.

[(B)Component] The composition of the present invention further contains polyfunctional (meth)acrylate (B) (also referred to as component (B) in this specification). From the viewpoint of easily obtaining high reaction speed and molding accuracy, and easily performing three-dimensional photomolding, the component (B) preferably has an acryl group. On the other hand, the methacrylyl group has greater steric hindrance at the α-position of the carbon-carbon double bond than the acrylyl group, easily causes depolymerization of the polymer, and has high disappearing properties when heated at high temperatures. , (B) component preferably has a methacryl group.

As the component (B), specifically, hydroxypivalate neopentyl glycol di(meth)acrylate, glycerin propylene oxide modified tri(meth)acrylate, 2-hydroxy-3- Acryloxypropyl (meth)acrylate, tris(hydroxyethyl)isocyanurate di(meth)acrylate, 3,9-bis[1,1-dimethyl-2-(methyl) )Acryloxyethyl]-2,4,8,10-tetrafluorospiro[5.5]undecane, dioxanediol di(meth)acrylate, (ethylene oxide, EO)) or (propylene oxide (PO)) modified bisphenol A di(meth)acrylate, (EO) or (PO) modified bisphenol E di(meth)acrylate, (EO ) or (PO) modified bisphenol F di(meth)acrylate, (EO) or (PO) modified bisphenol S di(meth)acrylate, (EO) or (PO) modified 4,4 '-Oxydibisphenol di(meth)acrylate and other difunctional (meth)acrylates;

EO modified glycerol tri(meth)acrylate, PO modified glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, EO modified phosphate tri(meth)acrylate, tris(meth)acrylate Hydroxymethylpropane tri(meth)acrylate, caprolactone modified trimethylolpropane tri(meth)acrylate, hydroxypropyl acrylate (HPA) modified trimethylolpropane tri(meth)acrylate base) acrylate, (EO) or (PO) modified trimethylolpropane tri(meth)acrylate, alkyl modified dipentaerythritol tri(meth)acrylate, tris(acryloxyethyl) Trifunctional (meth)acrylates such as isocyanurate;

Tetrafunctional (meth)acrylates such as di-trimethylolpropane tetra(meth)acrylate, pentaerythritol ethoxy tetra(meth)acrylate, and pentaerythritol tetra(meth)acrylate;

Pentafunctional (meth)acrylates such as dipentaerythritol hydroxypenta(meth)acrylate and alkyl-modified dipentaerythritol penta(meth)acrylate;

Hexafunctional (meth)acrylates such as dipentaerythritol hexa(meth)acrylate. These may be used individually or may be mixed and used appropriately in order to adjust hardening property, viscosity, etc.

The component (B) preferably contains a compound containing a plurality of oxygen atoms in the molecule in that the formed three-dimensional shaped object is easily decomposed when heated to high temperature and can produce water or carbon dioxide to reduce dust residue. Among these, compounds containing a polyoxyalkylene group in the structure are preferred.

Particularly preferred component (B) is a compound (B-1) having a polyoxyalkylene group and a bisphenol structure in the molecule. By having a bisphenol structure, the hardening speed is accelerated, the molding accuracy is improved, and three-dimensional molding is easy to perform.

The compound (B-1) used in the present invention is specifically represented by the following formula (I): [Chemical 1] represents, and R ¹ represents a hydrogen atom or a methyl group, multiple R ¹ in the same molecule may be the same or different, m and n each independently represent an integer of 1 or more.

In the compound (B-1), if m+n (mass modified) in the formula (I) is 2 or more, dust residue during calcination can be reduced. From the same viewpoint, m+n may be 4 or more or 6 or more. Furthermore, m+n only needs to be 40 or less, preferably 30 or less. Thereby, compared with the case where m+n exceeds 40, the toughness and strength of the formed three-dimensional shaped object are improved. In addition, when the multifunctional (meth)acrylate (B) contains a plurality of modified bisphenol A di(meth)acrylates of the formula (I) with different m+n, the average of these only needs to be 2 to 40 is enough.

When the compound (B-1) represented by the formula (I) has a methacryloyl group in the molecule, compared with the case where the compound (B-1) has an acrylyl group, dust residue during baking can be reduced. On the other hand, when priority is given to improving the hardening speed and molding accuracy rather than reducing dust residue, the compound (B-1) having an acryl group may be used.

As the compound (B-1) used in the present invention, for example, commercially available products such as MIRAMER M240, MIRAMER M241, MIRAMER M244, and MIRAMER can be used. ) M249, MIRAMER M2100, MIRAMER M2101, MIRAMER M2200, MIRAMER M2300, MIRAMER M2301 (all are product names. Mihara Special UV-curable resin sold under names such as Miwon Specialty Chemical Co., Ltd.

The polyfunctional (meth)acrylate (B) may contain a photopolymerizable component other than the compound (B-1) within the range in which the effects of the present invention are obtained. For example, the compound (B-2) having one or more (meth)acrylyl groups in the molecule may be further contained.

In order to reduce the residue during calcination, the compound (B-2) used in the present invention is preferably a compound containing only hydrogen atoms, carbon atoms, and oxygen atoms, and is particularly preferably a compound containing alcohol and (meth)acrylic acid. (Meth)acrylate compound obtained by dehydration condensation. As the compound (B-2), polyethylene glycol, polypropylene glycol, polytetramethylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, 1,3-propanediol, 1,2- Propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol Diol, 1,9-nonanediol, 1,10-decanediol, 2,2,4-trimethyl-1,3-pentanediol, 3-methyl-1,5-pentanediol, The reaction product of alcohols such as cyclohexane dimethylol, 1,4-cyclohexanediol, and tricyclodecane dimethylol and (meth)acrylic acid. These compounds may be used individually or in combination of 2 or more types. Among them, neopentyl glycol di(meth)acrylate or polypropylene glycol di(meth)acrylate is preferable from the viewpoint of increasing the hardness of the three-dimensional molded object, and from the viewpoint of reducing dust residue during firing Specifically, neopentyl glycol dimethacrylate or polypropylene glycol dimethacrylate is more preferred.

As the compound (B-2) used in the present invention, for example, commercially available products such as MIRAMER M213, MIRAMER M220, MIRAMER M221, and MIRAMER can be used. ) M222, MIRAMER M231, MIRAMER M232, MIRAMER M233, MIRAMER M235, MIRAMER M270, MIRAMER M280 , MIRAMER M281, MIRAMER M282, MIRAMER M283, MIRAMER M284, MIRAMER M286, MIRAMER M2040, m MIRAMER M2053 (all are product names. Manufactured by Miwon Specialty Chemical Co., Ltd.), NK ester A-200, NK ester A-400, NK ester A-600, NK ester A-1000, NK ester APG-100, NK ester APG-200, NK ester APG-400, NK ester APG-700, NK ester APMG-65, NK ester 2G, NK ester 3G, NK ester 4G, NK ester 9G, NK ester 14G, NK ester Compounds sold under the names 23G, NK ester 3PG, and NK ester 9PG (all are product names. Manufactured by Shin-Nakamura Chemical Industry Co., Ltd.).

When the polyfunctional (meth)acrylate (B) in the present invention contains both the compound (B-1) and the compound (B-2), relative to the polyfunctional (meth)acrylate (B) 100 parts by mass, the compounding amount of compound (B-1) is preferably in the range of 10 parts by mass or more and 99 parts by mass or less, more preferably in the range of 25 parts by mass or more and 95 parts by mass or less, particularly preferably 40 parts by mass or more And the range is less than 90 parts by mass. By setting it within these ranges, the hardening speed is appropriately accelerated, thereby improving the molding accuracy and reducing the residue during firing. The compounding amount of the compound (B-2) is preferably in the range of 5 to 80 parts by mass relative to 100 parts by mass of the polyfunctional (meth)acrylate (B), more preferably 8 to 65 parts by mass. The range is not more than 10 parts by mass and not more than 50 parts by mass. By setting it within these ranges, the hardness of the hardened material will be increased.

There is no particular limitation on the method for producing the photocurable resin composition, and it can be produced by any method.

The photocurable resin composition of the present invention may also contain photosensitizers, ultraviolet absorbers, antioxidants, polymerization inhibitors, silicon additives, fluorine additives, silane coupling agents, phosphate compounds, organic fillers, inorganic fillers, etc. Fillers, rheology control agents, defoaming agents, colorants and other additives.

Examples of the photosensitizer include amine compounds such as aliphatic amines and aromatic amines, urea compounds such as o-tolylthiourea, sodium diethyldithiophosphate, s-benzylisothiouronium- Sulfur compounds such as p-toluenesulfonate, etc.

Examples of the ultraviolet absorber include: 2-[4-{(2-hydroxy-3-dodecyloxypropyl)oxy}-2-hydroxyphenyl]-4,6-bis( 2,4-Dimethylphenyl)-1,3,5-triazine, 2-[4-{(2-hydroxy-3-tridecyloxypropyl)oxy}-2-hydroxybenzene methyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine and other triazine derivatives; 2-(2'-xanthenecarboxy-5'-methylbenzene benzotriazole, 2-(2'-o-nitrobenzyloxy-5'-methylphenyl)benzotriazole, 2-xanthenecarboxy-4-dodecyloxybenzophenone , 2-O-nitrobenzyloxy-4-dodecyloxybenzophenone, etc. These ultraviolet absorbers may be used alone or in combination of two or more types.

Examples of the antioxidant include hindered phenol antioxidants, hindered amine antioxidants, organic sulfur antioxidants, phosphate ester antioxidants, and the like. These antioxidants may be used alone or in combination of two or more types.

Examples of the polymerization inhibitor include hydroquinone, methoquinone, di-tert-butylhydroquinone, p-methoxyphenol, butylhydroxytoluene, and nitrosamine salts.

Examples of the silicone additive include: dimethyl polysiloxane, methylphenyl polysiloxane, cyclic dimethyl polysiloxane, methyl hydrogen polysiloxane, and modified polyether. Dimethyl polysiloxane copolymer, polyester modified dimethyl polysiloxane copolymer, fluorine modified dimethyl polysiloxane copolymer, amine modified dimethyl polysiloxane copolymer Polyorganosiloxanes with alkyl or phenyl groups, polyether-modified polydimethylsiloxane with acrylic groups, polyester-modified polydimethylsiloxanes with acrylic groups, etc. These silicon-based additives may be used alone or in combination of two or more types.

Examples of the fluorine-based additive include the "Megaface" series manufactured by DIC Co., Ltd. These fluorine-based additives may be used alone or in combination of two or more types.

Examples of the silane coupling agent include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane. , 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane Silane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethyl Oxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyl Methyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxy silane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylene)propyl amine, N-phenyl-3-aminopropyltrimethoxysilane, hydrochloride of N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane, Special aminosilane, 3-ureidopropyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, Bis(triethoxysilylpropyl)tetrasulfide, 3-isocyanatepropyltriethoxysilane, allyltrichlorosilane, allyltriethoxysilane, allyltrimethoxysilane, Vinyl-based silane coupling agents such as diethoxymethylvinylsilane and vinyltris(2-methoxyethoxy)silane;

Diethoxy(glycidyloxypropyl)methylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidyloxypropyltrimethoxysilane, 3 -Epoxy silane coupling agents such as glycidoxypropylmethyldiethoxysilane and 3-glycidoxypropyltriethoxysilane;

Styrenic silane coupling agents such as p-styrenetrimethoxysilane;

3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methyl (Meth)acryloxy-based silane coupling agents such as acryloxypropylmethyldiethoxysilane and 3-methacryloxypropyltriethoxysilane;

N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-( 2-Aminoethyl)-3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilane Amino-based silane coupling agents such as -N-(1,3-dimethyl-butylene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane;

Urea silane coupling agents such as 3-ureidopropyltriethoxysilane;

Chloropropyl silane coupling agents such as 3-chloropropyltrimethoxysilane;

Thiol-based silane coupling agents such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane;

Thioether silane coupling agents such as bis(triethoxysilylpropyl)tetrasulfide;

Isocyanate-based silane coupling agents such as 3-isocyanatepropyltriethoxysilane, etc. These silane coupling agents may be used alone or in combination of two or more.

Examples of the phosphate ester compound include compounds having a (meth)acrylyl group in the molecular structure. Examples of commercially available products include: "Kayamer PM-" manufactured by Nippon Kayaku Co., Ltd. 2", "Kayamer PM-21", "Light Ester (Light Ester) P-1M", "Light Ester (Light Ester) P-2M", "Light Ester (Light Ester) P-2M" manufactured by Kyeisha Chemical Co., Ltd. Acrylate (Light Acrylate) P-1A (N)", "SIPOMER PAM 100", "SIPOMER PAM 200", "SIPOMER ( SIPOMER PAM 300", "SIPOMER PAM 4000", "Viscoat #3PA", "Viscoat #3PMA" manufactured by Osaka Organic Chemical Industries, Ltd., Daiichi Industrial Pharmaceuticals "New Frontier S-23A" manufactured by the company; "SIPOMER PAM 5000" manufactured by the SOLVAY Company, which is a phosphate ester compound having an allyl ether group in the molecular structure, etc. .

Examples of the organic filler include solvent-insoluble substances derived from plants such as cellulose, lignin, and cellulose nanofibers, polymethylmethacrylate beads, polycarbonate beads, and polystyrene beads. , polyacrylic styrene beads, silicone beads, glass beads, acrylic beads, benzoguanamine resin beads, melamine resin beads, polyolefin resin beads, polyester resin beads, Organic beads such as polyamide resin beads, polyimide-based resin beads, polyvinyl fluoride resin beads, polyethylene resin beads, etc. These organic fillers may be used alone or in combination of two or more types.

Examples of the inorganic filler include inorganic fine particles such as silica, alumina, zirconium oxide, titanium dioxide, barium titanate, and antimony trioxide. These inorganic fillers may be used alone or in combination of two or more types. In addition, the average particle diameter of the inorganic fine particles is preferably in the range of 95 nm to 250 nm, and particularly preferably in the range of 100 nm to 180 nm.

When the inorganic fine particles are contained, a dispersion aid may be used. Examples of the dispersion aid include phosphate compounds such as isopropyl acid phosphate, triisodecyl phosphite, and ethylene oxide-modified phosphoric acid dimethacrylate. These dispersion aids may be used alone or in combination of two or more types. Examples of commercially available dispersion aids include "Kayamer PM-21" and "Kayamer PM-2" manufactured by Nippon Kayaku Co., Ltd. "Light Ester P-2M" manufactured by Eishe Chemical Co., Ltd., etc.

Examples of the rheology control agent include amide waxes such as "Disparlon 6900" manufactured by Kusumoto Chemical Co., Ltd.; "BYK410" manufactured by BYK-Chemie, etc. Urea-based rheology control agents; polyethylene waxes such as "Disparlon 4200" manufactured by Kusumoto Chemical Co., Ltd.; "CAB-381-2" manufactured by Eastman Chemical Products Co., Ltd. , "CAB 32101" and other cellulose acetate butyrate, etc.

Examples of the defoaming agent include oligomers containing fluorine or silicon atoms, or oligomers such as higher fatty acids and acrylic polymers.

Examples of the colorant include pigments, dyes, and the like.

As the pigment, well-known and commonly used inorganic pigments or organic pigments can be used.

Examples of the inorganic pigment include titanium oxide, antimony red, titanium oxide, cadmium red, cadmium yellow, cobalt blue, Prussian blue, ultramarine blue, carbon black, graphite, and the like.

Examples of the organic pigments include quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthraquinone pigments, indanthrene pigments, and flavans. Ketone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, azo pigments, etc. These pigments may be used individually or in combination of 2 or more types.

Examples of the dye include azo dyes such as monoazo and disazo, metal erium salt dyes, naphthol dyes, anthraquinone dyes, indigo dyes, carbonium dyes, and quinoneimine dyes. ) dyes, cyanine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, naphthalenedimine dyes, iconone dyes, phthalocyanine dyes, triallylmethane Department of dyes, etc. These dyes may be used individually or in combination of 2 or more types.

Among the colorants, from the viewpoint of reducing residue during baking, the non-metallic organic pigment (C) (hereinafter, also referred to as (C) component) is more preferred. Specifically, quinacridone pigments, quinacridonequinone pigments, dioxazine pigments, azo pigments, and the like are particularly preferred.

The content of the colorant in the composition of the present invention is preferably in the range of 0.001 to 5 parts by mass relative to 100 parts by mass of component (B), more preferably in the range of 0.001 to 1 part by mass, and particularly preferably The range is 0.001 parts by mass to 0.5 parts by mass. By setting it within these ranges, it is possible to suppress the generation of residue when the molded article is fired while improving visibility.

The cured product of the present invention is obtained by curing the photocurable resin composition.

The cured product of the present invention can be obtained by irradiating the photocurable resin composition with ultraviolet rays. In order to efficiently carry out the curing reaction using ultraviolet rays, it can be irradiated in an inert gas environment such as nitrogen or in an air environment. .

As a source of ultraviolet rays, ultraviolet lamps are generally used in terms of practicality and economy. Specifically, examples include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, xenon lamps, gallium lamps, metal halide lamps, sunlight, light emitting diodes (light emitting diodes, LEDs), and the like. Among these, in terms of obtaining stable illumination for a long time, it is preferable to use LED as the light source.

The wavelength of the ultraviolet ray is not particularly limited as long as it can cure the photocurable resin composition of the present invention, and can be appropriately selected in the range of 1 nm to 450 nm.

Furthermore, the ultraviolet irradiation can be performed in one stage, or can be divided into two or more stages.

The three-dimensional shaped object of the present invention can be produced by a known optical three-dimensional shaping method.

Examples of the optical three-dimensional modeling method include stereolithography (Stereo Lithography apparatus, SLA) method, digital light processing (DLP) method, liquid crystal display (LCD) method, and inkjet method. .

The so-called stereolithography (SLA) method is a method in which ultraviolet rays are irradiated in spots of a liquid photocurable resin composition tank, and the molding table is moved to solidify it layer by layer to perform three-dimensional molding.

The so-called digital light processing (DLP) method and the liquid crystal display (LCD) method perform three-dimensional modeling by irradiating ultraviolet rays on a surface of a groove of a liquid photocurable resin composition and hardening it layer by layer while moving the modeling table. Way.

The inkjet photolithography method is a method in which minute droplets of a photocurable resin composition are ejected from a nozzle to draw a predetermined shape pattern, and then ultraviolet rays are irradiated to form a cured film.

Among these optical three-dimensional modeling methods, the DLP method is preferred in terms of enabling high-speed surface-based modeling.

The DLP three-dimensional modeling method is not particularly limited as long as it uses a DLP light modeling system. As a forming condition, light modeling is required in order to improve the molding accuracy of the three-dimensional shaped object. The lamination spacing is in the range of 0.01 mm ~ 0.2 mm, the irradiation wavelength is in the range of 350 nm ~ 410 nm, the light intensity is in the range of 0.5 mW/cm ² ~ 50 mW/cm ² , and the cumulative light amount of each layer is 1 mJ/cm In the range of ² to 100 mJ/cm ² , in order to further improve the molding accuracy of the three-dimensional molded object, it is preferable that the lamination pitch of the photo-molding is in the range of 0.02 mm to 0.1 mm, and the irradiation wavelength is 380 nm to 410 nm, the light intensity is in the range of 5 mW/cm ² to 15 mW/cm ² , and the cumulative light amount of each layer is in the range of 5 mJ/cm ² to 80 mJ/cm ² .

Regarding the three-dimensional shaped object of the present invention, in terms of having excellent castability, the residual rate of the three-dimensional shaped object during firing is preferably 62% or less, more preferably, under the conditions of 400° C. in a nitrogen atmosphere. The best value is below 57%, and the best value is below 50%. Furthermore, in the present invention, the residual rate during calcination is [(weight at 400°C)/ (Initial weight at 25°C)] calculated value.

The three-dimensional shaped object of the present invention can be used for, for example, dental materials, automobile parts, aerospace-related parts, electrical and electronic parts, building materials, interior decoration, jewelry, medical materials, and the like.

Examples of the medical material include surgical guides for dental treatment, dental hard resin materials such as dentures, dental bridges, and orthodontic appliances.

In addition, since the three-dimensional molded object of the present invention has excellent hardness and castability, it is also suitable for the production of a casting mold using the three-dimensional molded object.

Examples of methods for manufacturing the casting mold include a method including the step (1) of embedding part or all of the three-dimensional molded object of the present invention with an embedding material, and hardening or solidifying the embedding material. Step (2), step (3) of melting, decomposing and/or incineration removing the three-dimensional shaped object.

Examples of the investment material include gypsum-based investment materials, phosphate-based investment materials, and the like. Examples of the gypsum-based investment materials include silica investment materials, quartz investment materials, and square investment materials. Silica investment materials, etc.

The step (1) is a step of embedding part or all of the three-dimensional sculpture of the present invention with an embedding material. At this time, it is preferable to knead the embedding material with an appropriate amount of water. If the water mixing ratio is too high, the hardening time will become longer. If the water mixing ratio is too small, the fluidity will become poor and the inflow of investment materials will become difficult. In addition, it is preferable to apply a surfactant to the three-dimensional shaped object because the embedding material is well wetted and fused, so that the surface of the cast object is less likely to become rough. Furthermore, when embedding the three-dimensional shaped object, it is preferable to embed it so that air bubbles do not adhere to the surface of the cast object.

The step (2) is a step of hardening or solidifying the investment material. When a gypsum-based investment material is used as the investment material, the temperature at which the investment material is cured is preferably in the range of 200°C to 400°C, and it is preferred that the three-dimensional sculpture be left to stand for 10 minutes after it is embedded. Let it cure in about 60 minutes.

The step (3) is a step of removing the three-dimensional shaped object by melting, decomposing and/or incineration. When the three-dimensional shaped object is removed by incineration, the calcination temperature is preferably in the range of 400°C to 1000°C, more preferably in the range of 600°C to 800°C.

In addition, the metal material can be poured into the casting mold obtained through the steps (1) to (3), and the metal material can be solidified (step (4)) to obtain a metal cast product. Thereby, a metal casting corresponding to the prototype of the three-dimensional shaped object can be produced. [Example]

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these Examples. (Hereinafter, "parts" described regarding the amounts of each component refer to "parts by mass")

(Example 1) In a container including a mixer, prepare 80 parts by mass of bisphenol A ethylene oxide modified (10 mol addition) dimethacrylate, 20 parts by mass of neopentyl glycol dimethacrylate, 2,4, 2 parts by mass of 6-trimethylbenzoyldiphenylphosphine oxide (trade name "Omnirad 819" manufactured by IGM), 1-hydroxycyclohexylphenyl ketone (trade name manufactured by IGM) Named "Omnirad (Omnirad) 184") 10 parts by mass, while controlling the liquid temperature to 60°C, stir and mix for 1 hour to uniformly dissolve, thereby obtaining a photocurable resin composition (1).

(Example 2 to Example 14, Comparative Example 1 to Comparative Example 5) Photocurable resin compositions (2) to (14) and photocurable resin composition (R1) were obtained in the same manner as in Example 1 except that the compositions shown in Tables 1 to 3 were changed. ~Photocurable resin composition (R5).

The photocurable resin composition (1) to photocurable resin composition (14) and photocurable resin composition (R1) to photocurable resin composition (R5) prepared as described above are made three-dimensional by the following steps. Samples of shaped objects and conduct various tests.

(Preparation of sample) Surface exposure method was used for each of the photocurable resin composition (1) to photocurable resin composition (14) and the photocurable resin composition (R1) to photocurable resin composition (R5). (DLP)'s light shaping system ("MAX" manufactured by ASIGA) formed a three-dimensional shaped object of a prescribed shape in each evaluation. The layer spacing of the photoforming was set to 0.05 mm to 0.1 mm, the irradiation wavelength was set to 400 nm to 410 nm, the illumination intensity was set to 8 mW/cm ² , and the light irradiation time was set to 0.5 seconds to 7 seconds per layer. The three-dimensional shaped objects formed under each of the above conditions were ultrasonically cleaned in ethanol. Next, a high-pressure mercury lamp is used to irradiate the surface and back of the three-dimensional molded object with light so that the cumulative light intensity becomes 1000 mJ/cm ² to 2000 mJ/cm ² , and the three-dimensional molded object is post-hardened to prepare a sample.

[Evaluation method of hardness (Shore-D hardness)] The hardness of the sample (D type Hardness tester, GS-720R). Using the sample obtained as described above (a rectangular parallelepiped with a shape of 5 mm × 5 mm × 3 mm), two samples of the same shape were stacked in the thickness direction of 3 mm, and the thickness was measured to be about 6 mm. However, do not use test pieces containing foreign matter, air bubbles, or scratches. Evaluation was performed based on the following standards, and ○ was considered as pass. (Evaluation criteria) ○ (Shore-D hardness is 60 or above) × (Shore-D hardness less than 60)

[Measurement method for the residual rate of three-dimensional shaped objects during firing] The prepared sample (rectangular parallelepiped with a shape of 5 mm × 5 mm × 3 mm) was crushed into pieces of 5 mg to 6 mg and used as test pieces. A differential thermogravimetric simultaneous measurement device (TG-DTA: Mei TGA/DSC1) manufactured by Mettler Toledo, measured in a nitrogen environment at a temperature of 10°C/min from 25°C to 600°C, based on [(weight at 400°C)/(25 Initial weight at ℃)] Calculate the residual rate at 400℃. The smaller this value is, the more excellent the disappearing properties during high-temperature heating are. The evaluation is based on the following criteria, and A or B is regarded as passing. (Evaluation criteria) A: (Survival rate is less than 57%) B: (The survival rate exceeds 57% and is below 62%) C: (The survival rate exceeds 62%)

[Measurement method of molding accuracy] For the photocurable resin composition (1) to photocurable resin composition (14), the photocurable resin composition (R1) to the photocurable resin composition (R5), each surface was used. A photolithography system (DLP) ("MAX" manufactured by ASIGA) is used to form a three-dimensional molded object into a sheet shape of 5 mm in length, 5 mm in width, and 1.5 mm in thickness. . The layer spacing of the photoforming was set to 0.05 mm, the irradiation wavelength was set to 400 nm to 410 nm, the illumination intensity was set to 8 mW/cm ² , and the light irradiation time was set to 6 seconds per layer. The formed three-dimensional shaped object was ultrasonically cleaned in ethanol. Next, a high-pressure mercury lamp is used to irradiate the surface and back of the three-dimensional molded object with light so that the cumulative light intensity becomes 1000 mJ/cm ² to 2000 mJ/cm ² , and the three-dimensional molded object is post-hardened to prepare a sample for molding accuracy measurement. The thickness of the obtained sample for molding accuracy measurement was measured using a micrometer. The closer the thickness is to 1.5 mm, the better the molding accuracy is. The evaluation is based on the following standards, and A or B is regarded as passing. (Evaluation criteria) A (The dimensional error of the thickness (1.5 mm) is less than 0.1 mm) B (The dimensional error of the thickness (1.5 mm) is 0.1 mm or more and less than 0.15 mm) C (The dimensional error of the thickness (1.5 mm) is 0.15 mm above)

[Evaluation method of castability] The sample obtained as described above was embedded using an investment material composed of silica investment material (Yoshino Gypsum Sales Co., Ltd., SAKURA Quick 30) and water mixed at a mass ratio of 100:33 (the shape is shown in the figure) 1: Use a cylinder with a diameter of 5 mm to connect a hemisphere with a diameter of 15 mm, a ball with a diameter of 15 mm, and a ring with a diameter of 15 mm. The total length is 42.5 mm). Let it stand for 30 minutes at 25°C to allow embedding. Material solidifies. Then, the sample was incinerated by heating in an electric furnace heated to 700° C. for 1 hour, and a casting mold was produced. The castability at this time was evaluated visually based on the following criteria. Furthermore, cut the mold inside the mold and visually determine whether there are cracks and cracks, whether there are residues and dust of the three-dimensional molded object, and whether the transferability of the three-dimensional molded object to the mold is good/poor, and ○ is set as passed. . (Evaluation criteria) ○: There are no cracks or cracks on the outside or inside of the mold. There is no residue or dust from the three-dimensional molded object inside the mold. The transferability of the three-dimensional molded object to the mold is good. ×: At least one of cracks and cracks on the outside of the mold, residues and dust of the three-dimensional molded object inside the mold, and poor transfer of the three-dimensional molded object to the mold have occurred, and the mold cannot be used as a mold.

The evaluation results of each test are described in Tables 1 to 3.

[Table 1] Example Composition (1) (2) (3) (4) (5) (6) (A) Ingredients (A-1) Omnirad 819 2 2 2 2 5 1 Omnirad TPO (A-2) Omnirad 184 10 10 15 20 7 20 Omnirad 907 Omnirad 651 (B) Ingredients (B-1) Compound 1 80 80 80 80 80 80 Compound 2 Compound 3 (B-2) Compound 4 20 20 20 20 20 20 Compound 5 (C) Ingredients PR122 0.01 Shore-D hardness ○ ○ ○ ○ ○ ○ Survival rate (400℃) A A A A B A Forming accuracy A A A A A A castability ○ ○ ○ ○ ○ ○

[Table 2] Example Composition (7) (8) (9) (10) (11) (12) (A) Ingredients (A-1) Omnirad 819 2 2 2 Omnirad TPO 12 2 2 (A-2) Omnirad 184 10 10 Omnirad 907 10 10 Omnirad 651 10 (B) Ingredients (B-1) Compound 1 80 80 80 80 80 90 Compound 2 Compound 3 (B-2) Compound 4 20 20 20 20 20 10 Compound 5 (C) Ingredients PR122 Shore-D hardness ○ ○ ○ ○ ○ ○ Survival rate (400℃) B A A A A A Forming accuracy B A A A A A castability ○ ○ ○ ○ ○ ○

[table 3] Example Comparative example Composition (13) (14) (R1) (R2) (R3) (R4) (R5) (A) Ingredients (A-1) Omnirad 819 2 2 2 5 7 2 2 Omnirad TPO (A-2) Omnirad 184 10 10 8 30 Omnirad 907 Omnirad 651 (B) Ingredients (B-1) Compound 1 60 80 80 80 80 80 Compound 2 50 Compound 3 20 (B-2) Compound 4 20 20 20 20 20 20 Compound 5 50 (C) Ingredients PR122 Shore-D hardness ○ ○ ○ ○ ○ ○ × Survival rate (400℃) A A C C C B A Forming accuracy A A A A B A A castability ○ ○ × × × × ×

The abbreviations in Tables 1 to 3 are as follows. Omnirad 819: Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, manufactured by IGM Company, trade name "Omnirad 819", maximum absorption wavelength : 237 nm, 380 nm Omnirad TPO: 2,4,6-Trimethylbenzyldiphenylphosphine oxide, manufactured by IGM Company, trade name "Omnirad TPO", maximum absorption wavelength: 275 nm, 379 nm Omnirad 184: 1-hydroxycyclohexyl phenyl ketone, manufactured by IGM, trade name "Omnirad 184", maximum absorption wavelength: 243 nm, 331 nm Omnirad 907: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylpropan-1-one, manufactured by IGM, trade name "Omnirad" (Omnirad) 907", maximum absorption wavelength: 230 nm, 303 nm Omnirad 651: 2,2-dimethoxy-2-phenylacetophenone, manufactured by IGM, trade name "Omnirad 651", maximum absorption wavelength: 252 nm, 325nm Compound 1: Bisphenol A ethylene oxide modified (10 mol addition) dimethacrylate, manufactured by Miwon Specialty Chemical Co., Ltd., trade name "Miramer M2101" Compound 2: Bisphenol A ethylene oxide modified (4 mol addition) dimethacrylate, manufactured by Miwon Specialty Chemical Co., Ltd., trade name "Miramer M241" Compound 3: Bisphenol A ethylene oxide modified (30 mol addition) dimethacrylate, manufactured by Miwon Specialty Chemical Company, trade name "Miramer M2301" Compound 4: Neopentyl glycol dimethacrylate, manufactured by Miwon Specialty Chemical Co., Ltd., trade name "Miramer M213" Compound 5: Polypropylene glycol dimethacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., trade name "NK ester 9PG" P.R.122: Pigment Red 122, manufactured by DIC Company, trade name "FASTOGEN (registered trademark) Super Magenta R"

As shown in Tables 1 to 3, it was confirmed that the photocurable resin compositions of Examples 1 to 14 showed good molding accuracy, and the three-dimensional molded objects showed high hardness and excellent disappearing properties when heated at high temperatures. And the castability becomes good. On the other hand, in the three-dimensional shaped objects formed from Comparative Examples 1 to 4 containing the photopolymerization initiator (A) in a proportion of 10 parts by mass or less with respect to 100 parts by mass of the component (B), high temperatures were confirmed It has poor disappearing properties and castability when heated. Furthermore, it was found that the three-dimensional molded article of Comparative Example 5 containing the photopolymerization initiator (A) in a ratio of 30 parts by weight or more relative to 100 parts by mass of the component (B) had a reduced hardness and deteriorated castability.

without

Fig. 1 is a photograph of a sample in the method for evaluating castability.

Claims (15)

A photocurable resin composition characterized by containing a photopolymerization initiator (A) and a multifunctional (meth)acrylate (B), The content of the photopolymerization initiator (A) is in the range of more than 10 parts by mass to 30 parts by mass relative to 100 parts by mass of the polyfunctional (meth)acrylate (B). The photocurable resin composition according to claim 1, wherein the photopolymerization initiator (A) contains at least a first photopolymerization initiator having at least one maximum absorption wavelength in a wavelength range above 350 nm. (A-1), and a second photopolymerization initiator (A-2) that does not have a maximum absorption wavelength in a wavelength range of 350 nm or more and has a maximum absorption wavelength in a wavelength range of less than 350 nm. The photocurable resin composition according to claim 2, wherein the first photopolymerization initiator (A-1) is selected from the group consisting of hydroxyl phosphine oxide, bisyl phosphine oxide, titanocene compound, O - At least one member from the group consisting of a acyl oxime compound and a thioxanthone compound. The photocurable resin composition according to claim 2, wherein the second photopolymerization initiator (A-2) is selected from the group consisting of phenylalkyl ketone compounds, α-diketone compounds and iodonium salts. At least one of the groups. The photocurable resin composition according to claim 2, wherein the blending ratio of the second photopolymerization initiator (A-2) to the first photopolymerization initiator (A-1) is [ (A-1)/(A-2)] is in the range of 1/100 to 8/10. The photocurable resin composition according to claim 1, wherein the polyfunctional (meth)acrylate (B) contains at least a compound having a polyoxyalkylene group in the molecule and the structure. The photocurable resin composition according to claim 6, wherein the polyfunctional (meth)acrylate (B) contains at least a compound (B-1) having a polyoxyalkylene group and a bisphenol structure in the molecule ), the compound (B-1) is modified bisphenol A di(meth)acrylate, which has the following formula (I): represents, and R ¹ represents a hydrogen atom or a methyl group, multiple R ¹ in the same molecule may be the same or different, m and n each independently represent an integer of 1 or more, and m+n is 2 to 40. The photocurable resin composition according to claim 6, wherein the polyfunctional (meth)acrylate (B) further contains a compound (B-) having one or more (meth)acrylyl groups in the molecule 2). The photocurable resin composition according to claim 8, wherein the compounding amount of the compound (B-1) in 100 parts by mass of the polyfunctional (meth)acrylate (B) is 40 parts by mass to 90 parts by mass. The photocurable resin composition according to claim 1 further contains a non-metallic organic pigment (C). The photocurable resin composition according to any one of claims 1 to 10 is used for stereolithography. A cured product obtained by photocuring the photocurable resin composition according to any one of claims 1 to 10. A three-dimensional shaped object including the hardened object according to claim 12. A method for manufacturing a casting mold, which is characterized by including: Step (1), using an embedding material to embed part or all of the three-dimensional sculpture as described in claim 13; Step (2), hardening or solidifying the investment material; and In step (3), the three-dimensional shaped object is removed by melting, decomposing and/or incineration. A method of manufacturing a metal casting, characterized by comprising step (4) of flowing a metal material into a casting mold obtained by the manufacturing method as described in claim 14 and causing the metal material to solidify.