Photocurable composition for stereolithography, three-dimensional article, and instrument used in oral cavity

Abstract

This photocurable composition for stereolithography comprising: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one group selected from the group consisting of groups (b1) to (b13); and a photopolymerization initiator. * indicates the bonding position. Any one of Rb1A to Rb1G is a divalent group, and the rest are H or a monovalent group. One of Rb2A and Rb2B is a divalent group, the other is H or a monovalent group, and each of Rb2C and Rb2D is H or a monovalent group. Any one of Rb3A to Rb3I is a divalent group, and the rest are H or a monovalent group. In the group (b5), each of Rb5A to Rb5H is H or a monovalent group.

Description

Photocurable composition for stereolithography, three-dimensional object, and instrument for use in the oral cavity

[0001] The present disclosure relates to a photocurable composition for stereolithography, a three-dimensional object, and an appliance for use in the oral cavity.

[0002] In recent years, dental products and other instruments used in the oral cavity have been studied. For example, from the viewpoint of the efficiency of forming these dental products, a method for producing three-dimensional objects such as dental products by stereolithography using a 3D printer is known (see, for example, Patent Document 1).

[0003] Patent Document 1: Patent No. 4160311

[0004] Intraoral appliances (e.g., splints) manufactured by stereolithography require mechanical properties such as tear strength. However, when the tear strength of the appliance is increased, the elongation at break of the appliance tends to decrease.

[0005] The problem to be solved by one embodiment of the present disclosure is to provide a photocurable composition for photopolymerization suitable for obtaining a cured product having excellent tear strength and elongation at break by photopolymerization, a three-dimensionally molded object having excellent tear strength and elongation at break, and an instrument for use in the oral cavity that includes the three-dimensionally molded object.

[0006] Specific means for solving the above problems are as follows: <1> A photocurable composition for stereolithography, comprising: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of the following groups (b1) to (b13); and a photopolymerization initiator:

[0007]

[0008] In group (b1), R ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ any one of R is a divalent hydrocarbon group;ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ The remainder of the groups (b2) are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ２Ａ and R ｂ２Ｂ one of which is a divalent hydrocarbon group, and R ｂ２Ａ and R ｂ２Ｂ the other is a hydrogen atom or a monovalent hydrocarbon group, and R ｂ２Ｃ and R ｂ２Ｄ are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ any one of R is a divalent hydrocarbon group; ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ The remainders of each of the groups are independently a hydrogen atom or a monovalent hydrocarbon group, and the double line consisting of a solid line and a dashed line represents a single bond or a double bond. In the group (b4), * represents the bonding position. In the group (b5), R ｂ５Ａ , R ｂ５Ｂ , and R ｂ５Ｃ are each independently a monovalent hydrocarbon group which may have an oxo group (i.e., a group represented by "=O"; the same applies hereinafter) as a substituent, and R ｂ５Ｄ and R ｂ５Ｅ are each independently a hydrogen atom or a monovalent hydrocarbon group, or R ｂ５Ｄ and R ｂ５Ｅ together form an oxo group, R ｂ５Ｆ is a hydrogen atom or a monovalent hydrocarbon group, R ｂ５Ｇ and R ｂ５Ｈare each independently a hydrogen atom or a monovalent hydrocarbon group which may have an alkoxy group as a substituent, or R ｂ５Ｇ and R ｂ５Ｈ together form an oxo group, and * indicates the bonding position. In groups (b6) to (b13), * indicates the bonding position.

[0009] <2> The photocurable composition for stereolithography according to <1>, wherein the di(meth)acrylic monomer (A) has a molecular weight of 500 to 100,000. <3> The photocurable composition for stereolithography according to <1> or <2>, wherein the mono(meth)acrylic monomer (B) has a molecular weight of 150 to 400. <4> The photocurable composition for stereolithography according to any one of <1> to <3>, wherein the content of the di(meth)acrylic monomer (A) is 5% by mass to 85% by mass, based on the total amount of the photocurable composition for stereolithography. <5> The photocurable composition for stereolithography according to any one of <1> to <4>, wherein the content of the mono(meth)acrylic monomer (B) is 10% by mass to 95% by mass, based on the total amount of the photocurable composition for stereolithography. <6> The photocurable composition for stereolithography according to any one of <1> to <5>, wherein the content of the mono(meth)acrylic monomer (B) is 15% by mass to 49% by mass, based on the total amount of the photocurable composition for stereolithography. <7> The photocurable composition for stereolithography according to any one of <1> to <6>, wherein the total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) is 60% by mass or more, based on the total amount of the photocurable composition for stereolithography. <8> The photocurable composition for stereolithography according to any one of <1> to <6>, wherein the total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) is 60% by mass or more, based on the total amount of the photocurable composition for stereolithography. ２ The cured layers A1 are laminated in the thickness direction to form a 100 μm thick cured layer A1, and a shaped object A1 having a DIE C shape as defined in ASTM D 624 (2020) is formed. The shaped object A1 is then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at a dose of 8252 J / cm at a wavelength of 405 nm. ２A test piece A1 having the DIE C shape was prepared by irradiating the photocurable composition for stereolithography with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm. When the tear strength of the test piece A1 was measured in accordance with ASTM D 624 (2020), the tear strength of the test piece A1 was 10 N / mm to 300 N / mm. ２ The cured layers B1 are laminated in the thickness direction to form a 100 μm-thick hardened layer B1, and a shaped object B1 having a No. 6 dumbbell shape as specified in JIS K 6251:2017 is formed. The hardened layers B1 are then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at an irradiation dose of 8252 J / cm at a wavelength of 405 nm. ２ The photocurable composition for stereolithography according to any one of <1> to <7>, wherein a dumbbell-shaped test piece B1 is prepared by irradiating the composition with an irradiation amount satisfying the following: and when the elongation at break of the test piece B1 is measured in accordance with JIS K 6251:2017, the elongation at break of the test piece B1 is 40% to 1000%. <9> The photocurable composition for stereolithography according to <8>, wherein the tear strength is 100 N / mm to 300 N / mm, and the elongation at break is 40% to 800%. <10> The photocurable composition for stereolithography according to any one of <1> to <9>, which is used in the manufacture of an instrument for intraoral use. <11> A three-dimensional object that is a cured product of the photocurable composition for stereolithography according to any one of <1> to <10>. <12> An instrument for intraoral use, comprising the three-dimensional object according to <11>.

[0010] According to one aspect of the present disclosure, there are provided a photocurable composition for photopolymerization suitable for obtaining a cured product having excellent tear strength and elongation at break by photopolymerization, a three-dimensionally shaped object having excellent tear strength and elongation at break, and an appliance for use in the oral cavity that includes the three-dimensionally shaped object.

[0011] In this disclosure, a numerical range indicated using "to" means a range that includes the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In this disclosure, the term "process" includes not only an independent process, but also a process that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved. In this disclosure, when there are multiple substances corresponding to each component, the amount of each component refers to the total amount of multiple substances unless otherwise specified. In this disclosure, "(meth)acryloyl group" means acryloyl group and methacryloyl group, and "(meth)acrylate" means acrylate and methacrylate. In this disclosure, "*" in a chemical formula indicates a bonding site.

[0012] A first embodiment and a second embodiment of the present disclosure will be described below. There may be an overlap between the first embodiment and the second embodiment. For example, the photocurable composition for stereolithography of the first embodiment may have the characteristics of the photocurable composition for stereolithography of the second embodiment.

[0013] First Embodiment

[0014] <Photocurable composition for stereolithography> The photocurable composition for stereolithography of the first embodiment (hereinafter also simply referred to as "photocurable composition of the first embodiment") comprises: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of the following groups (b1) to (b13); and a photopolymerization initiator. The photocurable composition of the first embodiment may contain other components.

[0015]

[0016] In group (b1), R ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ any one of R is a divalent hydrocarbon group; ｂ１Ａ , R ｂ１Ｂ , Rｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ The remainder of the groups (b2) are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ２Ａ and R ｂ２Ｂ one of which is a divalent hydrocarbon group, and R ｂ２Ａ and R ｂ２Ｂ the other is a hydrogen atom or a monovalent hydrocarbon group, and R ｂ２Ｃ and R ｂ２Ｄ are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ any one of R is a divalent hydrocarbon group; ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ The remainders of each of the groups are independently a hydrogen atom or a monovalent hydrocarbon group, and the double line consisting of a solid line and a dashed line represents a single bond or a double bond. In the group (b4), * represents the bonding position. In the group (b5), R ｂ５Ａ , R ｂ５Ｂ , and R ｂ５Ｃ are each independently a monovalent hydrocarbon group which may have an oxo group as a substituent, and R ｂ５Ｄ and R ｂ５Ｅ are each independently a hydrogen atom or a monovalent hydrocarbon group, or R ｂ５Ｄ and R ｂ５Ｅ together form an oxo group, R ｂ５Ｆ is a hydrogen atom or a monovalent hydrocarbon group, R ｂ５Ｇ and R ｂ５Ｈ are each independently a hydrogen atom or a monovalent hydrocarbon group which may have an alkoxy group as a substituent, or R ｂ５Ｇand R ｂ５Ｈ together form an oxo group, and * indicates the bonding position. In groups (b6) to (b13), * indicates the bonding position.

[0017] The photocurable composition of the first embodiment is suitable for obtaining a cured product (e.g., a three-dimensional object; the same applies below) having excellent tear strength and elongation at break by stereolithography. That is, a cured product obtained by stereolithography using the photocurable composition of the first embodiment has excellent tear strength and elongation at break. The effect of the cured product having excellent tear strength and elongation at break is thought to be an effect obtained by combining the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B).

[0018] <Di(meth)acrylic monomer (A)> The photocurable composition of the first embodiment contains a di(meth)acrylic monomer (A). The di(meth)acrylic monomer (A) is a compound containing two (meth)acryloyloxy groups (i.e., a di(meth)acrylate). The photocurable composition of the first embodiment may contain only one type of di(meth)acrylic monomer (A), or may contain two or more types of di(meth)acrylic monomer (A).

[0019] The di(meth)acrylic monomer (A) may include a compound containing two (meth)acryloyloxy groups and at least one (preferably two or more) urethane bond. For example, the di(meth)acrylate monomer (A) may include a compound represented by the following formula (A-1):

[0020]

[0021] In formula (A-1), X is a divalent organic group, and R １Ａ and R ２Ａ are each independently a divalent hydrocarbon group which may have a substituent, and R ３Ａ and R ４Ａ are each independently a divalent organic group, ５Ａ and R ６Ａ are each independently a methyl group or a hydrogen atom, and n is an integer of 0 to 10.

[0022] In formula (A-1), X is a divalent organic group. The divalent organic group represented by X preferably contains at least one bond selected from the group consisting of a carbonate bond, an ether bond, and an ester bond.

[0023] When the divalent organic group represented by X contains an ether bond, the number of ether bonds is preferably 1 to 100, more preferably 2 to 90, and even more preferably 4 to 80. When the divalent organic group represented by X contains an ester bond, the number of ester bonds is preferably 1 to 100, more preferably 2 to 90, and even more preferably 4 to 80. When the divalent organic group represented by X contains a carbonate bond, the number of carbonate bonds is preferably 1 to 100, more preferably 2 to 90, and even more preferably 4 to 80. The number of carbon atoms in the divalent organic group represented by X is preferably 2 to 500, more preferably 2 to 400, and even more preferably 2 to 300.

[0024] The divalent organic group represented by X is more preferably a group represented by the following formula (X-1).

[0025]

[0026] In formula (X-1), R １Ｘ and R ２Ｘ are each independently a divalent hydrocarbon group, and R ３Ｘ represents a methylene group or an oxygen atom. a and b each independently represent an integer of 1 to 150. c represents an integer of 0 to 100.

[0027] In formula (X-1), R １Ｘ and R ２Ｘ The number of carbon atoms in the divalent hydrocarbon groups represented by R is not particularly limited, and they may be the same or different from each other. From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, １Ｘ and R ２Ｘ The number of carbon atoms in the divalent hydrocarbon group represented by R is preferably 1 or more, and more preferably 2 or more. From the viewpoint of further suppressing the viscosity of the photocurable composition, １Ｘ and R ２ＸThe divalent hydrocarbon group represented by the formula (I) preferably has 10 or less carbon atoms, more preferably 9 or less carbon atoms, and even more preferably 8 or less carbon atoms.

[0028] R １Ｘ and R ２Ｘ Each of the divalent hydrocarbon groups represented by the formula (I) is preferably a linear or branched alkylene group, and more preferably an ethylene group, a propylene group, a hexyl group, an isobutyl group, or a tetramethylene group.

[0029] From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, a and b are each independently preferably equal to or greater than 1, and more preferably equal to or greater than 2. From the viewpoint of further suppressing the viscosity of the photocurable composition, a and b are each independently preferably equal to or less than 100, more preferably equal to or less than 50, and even more preferably equal to or less than 30.

[0030] From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, c is preferably at least 1, more preferably at least 2, and even more preferably at least 3. From the viewpoint of further suppressing the viscosity of the photocurable composition, c is preferably at most 50, more preferably at most 20, and even more preferably at most 10.

[0031] In formula (A-1), R １Ａ and R ２Ａ R are each independently a divalent hydrocarbon group which may have a substituent. １Ａ and R ２Ａ The number of carbon atoms in the divalent hydrocarbon groups represented by R is not particularly limited, and they may be the same or different. １Ａ and R ２Ａ The number of carbon atoms in the divalent hydrocarbon group represented by R may be, for example, 2 to 30. From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, １Ａ and R ２ＡThe number of carbon atoms in the divalent hydrocarbon groups represented by R is preferably 3 or more, more preferably 4 or more, and even more preferably 5 or more. From the viewpoint of further suppressing the viscosity of the photocurable composition, １Ａ and R ２Ａ The number of carbon atoms in the divalent hydrocarbon groups represented by the following formula (I) is preferably 25 or less, more preferably 20 or less, and even more preferably 15 or less.

[0032] R １Ａ and R ２Ａ Examples of the divalent hydrocarbon group represented by the formula (I) include a divalent chain hydrocarbon group and a divalent hydrocarbon group containing a ring structure. The ring structure that can be contained in the hydrocarbon group may be an aromatic structure or an alicyclic structure.

[0033] R １Ａ and R ２Ａ The number of carbon atoms in the divalent chain hydrocarbon group in R is preferably 1 to 25, more preferably 1 to 20, and even more preferably 2 to 15. １Ａ and R ２Ａ The divalent chain hydrocarbon group in R may be linear or branched, and may be saturated or unsaturated. １Ａ and R ２Ａ The divalent chain hydrocarbon group in the formula (I) is preferably a linear or branched alkylene group having 1 to 25 carbon atoms, more preferably a linear or branched alkylene group having 1 to 20 carbon atoms, and even more preferably a linear or branched alkylene group having 2 to 15 carbon atoms.

[0034] R １Ａ and R ２Ａ The divalent hydrocarbon group containing an aromatic structure in R is preferably a divalent hydrocarbon group containing an aromatic structure having 6 to 25 carbon atoms (more preferably 6 to 20 carbon atoms, and even more preferably 6 to 15 carbon atoms) which may have a substituent. Examples of the substituent include a linear or branched alkyl group having 1 to 6 carbon atoms. １Ａ and R ２ＡExamples of the divalent hydrocarbon group containing an aromatic structure in R include an arylene group, an alkylenearylene group, an alkylenearylenealkylene group, and an arylenealkylenearylene group. １Ａ and R ２Ａ The divalent hydrocarbon group containing an aromatic structure in the formula (I) is preferably an alkylenearylene group or an alkylenearylenealkylene group.

[0035] R １Ａ and R ２Ａ The divalent hydrocarbon group containing an alicyclic structure in R is preferably a divalent hydrocarbon group containing an alicyclic structure having 3 to 20 carbon atoms (more preferably 6 to 12 carbon atoms, and even more preferably 6 to 8 carbon atoms) which may have a substituent. Examples of the substituent include a linear or branched alkyl group having 1 to 6 carbon atoms. １Ａ and R ２Ａ Examples of the divalent hydrocarbon group containing an alicyclic structure in the formula (I) include a bicyclohexylene group, a norbornylene group, an isobornylene group, an adamantylene group, and a methylenebiscyclohexylene group.

[0036] R １Ａ and R ２Ａ The divalent hydrocarbon group represented by the formula (I) is preferably any one of the following groups (a-1) to (a-13), and more preferably any one of the following groups (a-4) to (a-13).

[0037]

[0038] In the groups (a-1) to (a-13), * indicates a bonding position.

[0039] In formula (A-1), R ３Ａ and R ４Ａ are each independently a divalent organic group. ３Ａ and R ４Ａ Examples of the divalent organic groups represented by the formula (R) include divalent organic groups each independently containing one or more bonds selected from the group consisting of a divalent hydrocarbon group, an ether bond, and an ester bond. ３Ａ and R ４ＡExamples of the divalent hydrocarbon groups in the divalent organic group represented by the formula (R) include, independently, divalent chain hydrocarbon groups and divalent hydrocarbon groups containing a ring structure (aromatic ring structure, alicyclic structure). ３Ａ and R ４Ａ When the divalent organic group represented by R contains an ether bond, the number of ether bonds is preferably 1 to 30, more preferably 1 to 20, and even more preferably 1 to 15. ３Ａ and R ４Ａ When the divalent organic group represented by R contains an ester bond, the number of ester bonds is preferably 1 to 12, more preferably 1 to 8, and even more preferably 1 to 6. ３Ａ and R ４Ａ The number of carbon atoms in each of R may be, for example, 2 to 60, preferably 2 to 40, and more preferably 2 to 30. ３Ａ and R ４Ａ is preferably a group represented by the following formula (Y-1):

[0040]

[0041] In formula (Y-1), R ７Ａ is a divalent hydrocarbon group which may have a substituent, and R ８Ａ is a methylene group (-CH ２ -) or a carbonyl group (-C(=O)-), and R ９Ａ is a divalent hydrocarbon group, and m is 0 to 10. ８Ａ and R ９Ａ When there are a plurality of such groups, they may be the same or different.

[0042] R ７Ａ Specific examples of the optionally substituted divalent hydrocarbon group represented by the formula (I) include the above-mentioned R １Ａ and R ２Ａ and R １Ｘ and R ２Ｘ Specific examples of the divalent hydrocarbon group represented by the following formula include the same groups as those shown below.

[0043] R ７ＡThe optionally substituted divalent hydrocarbon group represented by the formula (I) is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms, even more preferably an alkylene group having 1 to 4 carbon atoms, and even more preferably an ethylene group. ７Ａ Examples of the substituent that the divalent hydrocarbon group represented by the formula (I) may have include an alkoxy group, an aryloxy group, an alkylaryloxy group, and a combination thereof, and an aryloxy group (such as a phenoxy group) is preferred.

[0044] In formula (Y-1), m is preferably 0 to 6, and more preferably 0.

[0045] In formula (A-1), n ​​is an integer of 0 to 10. n is preferably an integer of 1 to 10, more preferably an integer of 1 to 8, and even more preferably an integer of 1 to 4.

[0046] The molecular weight of the di(meth)acrylic monomer (A) is not particularly limited. From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, the molecular weight of the di(meth)acrylic monomer (A) is preferably 500 or more, more preferably 800 or more, and even more preferably 1,000 or more. From the viewpoint of further suppressing the viscosity of the photocurable composition, the molecular weight of the di(meth)acrylic monomer (A) is preferably 100,000 or less, more preferably 80,000 or less, and even more preferably 60,000 or less. An example of a preferred range for the molecular weight of the di(meth)acrylic monomer (A) is 500 to 100,000.

[0047] In the present disclosure, the molecular weight, number average molecular weight or weight average molecular weight of the di(meth)acrylic monomer (A) is measured by gel permeation chromatography (GPC).

[0048] The number average molecular weight (Mn) of the di(meth)acrylic monomer (A) is not particularly limited. From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, the number average molecular weight of the di(meth)acrylic monomer (A) is preferably 700 or more, more preferably 800 or more, and even more preferably 1000 or more. From the viewpoint of further suppressing the viscosity of the photocurable composition, the number average molecular weight of the di(meth)acrylic monomer (A) is preferably 20,000 or less, more preferably 18,000 or less, more preferably 16,000 or less, more preferably 10,000 or less, and even more preferably 5,000 or less. An example of a preferred range of the number average molecular weight (Mn) of the di(meth)acrylic monomer (A) is 700 to 20,000.

[0049] The weight average molecular weight (Mw) of the di(meth)acrylic monomer (A) is not particularly limited. From the viewpoint of further improving the tear strength and / or elongation at break of the cured product, the weight average molecular weight of the di(meth)acrylic monomer (A) is preferably 1,000 or more, more preferably 2,000 or more, and even more preferably 3,000 or more. From the viewpoint of further suppressing the viscosity of the photocurable composition, the weight average molecular weight of the di(meth)acrylic monomer (A) is preferably 50,000 or less, more preferably 30,000 or less, and even more preferably 20,000 or less. An example of a preferred range for the weight average molecular weight (Mw) of the di(meth)acrylic monomer (A) is 1,000 to 50,000.

[0050] The molecular structure of the di(meth)acrylic monomer (A) may be changed by selecting the type of monomer used to synthesize the di(meth)acrylic monomer (A). For example, a compound having a divalent organic group represented by X in formula (A-1) and two hydroxyl groups (hereinafter also referred to as Monomer 1) and a compound having R in formula (A-1) １Ａ or R ２Ａ and two isocyanate groups (hereinafter also referred to as Monomer 2), and ３Ａ or R４Ａ A di(meth)acrylic monomer (A) represented by formula (A-1) can be synthesized by reacting a compound having a divalent hydrocarbon group represented by the formula (A), one (meth)acryloyl group, and one hydroxyl group (hereinafter also referred to as monomer 3) with the formula (A-1). The synthesis may be carried out in one step or in two separate steps. For example, monomer 1 may be reacted with monomer 2, and then the product obtained by this reaction may be reacted with monomer 3. Monomer 1, monomer 2, and monomer 3 used in the synthesis may each be one type or two or more types.

[0051] Specific examples of Monomer 1 include diols containing one or more carbonate bonds and one or more ether bonds. Commercially available products include polyether polycarbonate diol (PEPCD) manufactured by Mitsubishi Chemical Corporation. ＴＭ ) are listed.

[0052] Specific examples of Monomer 2 include diisocyanates represented by the following structures: In the following structures, "Me" represents a methyl group.

[0053]

[0054] Specific examples of Monomer 3 include hydroxyalkyl(meth)acrylates such as hydroxyethyl(meth)acrylate, hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, and 2-hydroxy-3-phenoxypropyl acrylate. The alkyl moiety of the hydroxyalkyl(meth)acrylate may have an aryloxy group (such as a phenoxy group) as a substituent.

[0055] The content of the di(meth)acrylic monomer (A) is preferably 3% by mass to 85% by mass, more preferably 5% by mass to 85% by mass, even more preferably 5% by mass to 70% by mass, and even more preferably 5% by mass to 60% by mass, relative to the total amount of the photocurable composition for stereolithography. When the content of the di(meth)acrylic monomer (A) relative to the total amount of the photocurable composition for stereolithography is 85% by mass or less, the viscosity of the photocurable composition is further reduced.

[0056] The content of the di(meth)acrylic monomer (A) is preferably 3% by mass to 85% by mass, more preferably 5% by mass to 85% by mass, even more preferably 5% by mass to 70% by mass, and even more preferably 5% by mass to 60% by mass, based on the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography. When the content of the di(meth)acrylic monomer (A) based on the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography is 85% by mass or less, the viscosity of the photocurable composition is further reduced.

[0057] <Mono(meth)acrylic monomer (B)> The photocurable composition of the first embodiment contains a mono(meth)acrylic monomer (B). The mono(meth)acrylic monomer (B) is a compound containing one (meth)acryloyloxy group and at least one selected from the group consisting of the following groups (b1) to (b13). That is, the mono(meth)acrylic monomer (B) is a mono(meth)acrylate containing at least one selected from the group consisting of the following groups (b1) to (b13). It is believed that the at least one selected from the group consisting of the following groups (b1) to (b13) contained in the mono(meth)acrylic monomer (B) contributes to the effects of improving the tear strength and / or elongation at break of the cured product. The photocurable composition of the first embodiment may contain only one type of mono(meth)acrylic monomer (B), or may contain two or more types of mono(meth)acrylic monomer (B).

[0058]

[0059] In group (b1), R ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ any one of R is a divalent hydrocarbon group; ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ The remainder of the groups (b2) are each independently a hydrogen atom or a monovalent hydrocarbon group.ｂ２Ａ and R ｂ２Ｂ one of which is a divalent hydrocarbon group, and R ｂ２Ａ and R ｂ２Ｂ the other is a hydrogen atom or a monovalent hydrocarbon group, and R ｂ２Ｃ and R ｂ２Ｄ are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ any one of R is a divalent hydrocarbon group; ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ The remainders of each of the groups are independently a hydrogen atom or a monovalent hydrocarbon group, and the double line consisting of a solid line and a dashed line represents a single bond or a double bond. In the group (b4), * represents the bonding position. In the group (b5), R ｂ５Ａ , R ｂ５Ｂ , and R ｂ５Ｃ are each independently a monovalent hydrocarbon group which may have an oxo group as a substituent, and R ｂ５Ｄ and R ｂ５Ｅ are each independently a hydrogen atom or a monovalent hydrocarbon group, or R ｂ５Ｄ and R ｂ５Ｅ together form an oxo group, R ｂ５Ｆ is a hydrogen atom or a monovalent hydrocarbon group, R ｂ５Ｇ and R ｂ５Ｈ are each independently a hydrogen atom or a monovalent hydrocarbon group which may have an alkoxy group as a substituent, or R ｂ５Ｇ and R ｂ５Ｈ together form an oxo group, and * indicates the bonding position. In groups (b6) to (b13), * indicates the bonding position.

[0060] As described above, in group (b1), Rｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ any one of R is a divalent hydrocarbon group; ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ The remainder of each independently represent a hydrogen atom or a monovalent hydrocarbon group.

[0061] The group (b1) does not have the symbol "*", but is a monovalent group like the groups (b4) to (b13) that have the symbol "*". In the group (b1), one of the two bonding positions present in the divalent hydrocarbon group corresponds to the bonding position of the group (b1). In the group (b1), the divalent hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. In the group (b1), the monovalent hydrocarbon groups each independently have 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. The following groups (b1-1) to (b1-3) are particularly preferred as the group (b1):

[0062]

[0063] In the group (b1-1), * denotes a bonding position. In the group (b1-2), * denotes a bonding position. In the group (b1-3), * denotes a bonding position.

[0064] As described above, in group (b2), R ｂ２Ａ and R ｂ２Ｂ one of which is a divalent hydrocarbon group, and R ｂ２Ａ and R ｂ２Ｂ the other is a hydrogen atom or a monovalent hydrocarbon group, and R ｂ２Ｃ and R ｂ２Ｄ are each independently a hydrogen atom or a monovalent hydrocarbon group.

[0065] The group (b2) does not have the symbol "*", but is a monovalent group like the groups (b4) to (b7) that have the symbol "*". In the group (b2), one of the two bonding positions present in the divalent hydrocarbon group corresponds to the bonding position of the group (b2). In the group (b2), the divalent hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. In the group (b2), the monovalent hydrocarbon groups each independently have 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. The following groups (b2-1) to (b2-3) are particularly preferred as the group (b2):

[0066]

[0067] In the group (b2-1), * denotes a bonding position. In the group (b2-2), * denotes a bonding position. In the group (b2-3), * denotes a bonding position.

[0068] As described above, in the group (b3), R ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ any one of R is a divalent hydrocarbon group; ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ The remainders are each independently a hydrogen atom or a monovalent hydrocarbon group, and the double line consisting of a solid line and a dashed line represents a single bond or a double bond.

[0069] The group (b3) does not have the symbol "*", but is a monovalent group like the groups (b4) to (b7) that have the symbol "*". In the group (b3), one of the two bonding positions present in the divalent hydrocarbon group corresponds to the bonding position of the group (b2). In the group (b3), the divalent hydrocarbon group preferably has 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. In the group (b3), the monovalent hydrocarbon groups each independently have 1 to 10 carbon atoms, more preferably 1 to 6, and even more preferably 1 to 3 carbon atoms. The following groups (b3-1) to (b3-5) are particularly preferred as the group (b3):

[0070]

[0071] In the group (b3-1), * denotes a bonding position. In the group (b3-2), * denotes a bonding position. In the group (b3-3), * denotes a bonding position. In the group (b3-4), * denotes a bonding position. In the group (b3-5), * denotes a bonding position.

[0072] In the group (b5), R ｂ５Ａ , R ｂ５Ｂ , and R ｂ５Ｃ are each independently a monovalent hydrocarbon group which may have an oxo group as a substituent, and R ｂ５Ｄ and R ｂ５Ｅ are each independently a hydrogen atom or a monovalent hydrocarbon group, or R ｂ５Ｄ and R ｂ５Ｅ together form an oxo group, R ｂ５Ｆ is a hydrogen atom or a monovalent hydrocarbon group, R ｂ５Ｇ and R ｂ５Ｈ are each independently a hydrogen atom or a monovalent hydrocarbon group which may have an alkoxy group as a substituent, or R ｂ５Ｇ and R ｂ５Ｈ together form an oxo group, and * indicates the bonding position.

[0073] R ｂ５Ａ , R ｂ５Ｂ , or R ｂ５ＣThe number of carbon atoms in the monovalent hydrocarbon group represented by the following formula (1), which may have an oxo group as a substituent, is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. ｂ５Ｄ or R ｂ５Ｅ When R are monovalent hydrocarbon groups, each independently has preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 3 carbon atoms. ｂ５Ｆ When R is a monovalent hydrocarbon group, it preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 3 carbon atoms. ｂ５Ｇ or R ｂ５Ｈ However, when it is a monovalent hydrocarbon group which may have an alkoxy group as a substituent, the number of carbon atoms (when it has an alkoxy group, the number of carbon atoms excluding the carbon atoms of the alkoxy group) is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3. The number of carbon atoms of the alkoxy group referred to here is preferably 1 to 10, more preferably 1 to 6, and even more preferably 1 to 3.

[0074] Particularly preferred as the group (b5) are the following groups (b5-1) to (b5-8):

[0075]

[0076] In group (b5-1), * denotes a bonding position. In group (b5-2), * denotes a bonding position. In group (b5-3), * denotes a bonding position. In group (b5-4), * denotes a bonding position. In group (b5-5), * denotes a bonding position. In group (b5-6), * denotes a bonding position. In group (b5-7), * denotes a bonding position. In group (b5-8), * denotes a bonding position.

[0077] The mono(meth)acrylic monomer (B) may be a compound containing one (meth)acryloyloxy group and at least one selected from the group consisting of the following groups (b1) to (b7):

[0078] The molecular weight of the mono(meth)acrylic monomer (B) is preferably 150 to 400.

[0079] The content of the mono(meth)acrylic monomer (B) is preferably 10% by mass to 95% by mass, more preferably 10% by mass to 80% by mass, and even more preferably 15% by mass to 49% by mass, based on the total amount of the photocurable composition for stereolithography. When the content of the mono(meth)acrylic monomer (B) is 10% by mass or more, the viscosity of the photocurable composition is further reduced.

[0080] The content of the mono(meth)acrylic monomer (B) is preferably 10% by mass to 95% by mass, more preferably 10% by mass to 80% by mass, and even more preferably 15% by mass to 49% by mass, based on the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography. When the content of the mono(meth)acrylic monomer (B) is 10% by mass or more, the viscosity of the photocurable composition is further reduced.

[0081] The total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more, based on the total amount of the photocurable composition for stereolithography.

[0082] The total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) is preferably 40% by mass or more, more preferably 50% by mass or more, even more preferably 60% by mass or more, even more preferably 80% by mass or more, and even more preferably 90% by mass or more, based on the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography. The total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) may be 100% by mass, based on the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography.

[0083] <Other (meth)acrylic monomers> The photocurable composition of the first embodiment may contain at least one other (meth)acrylic monomer other than the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B). Examples of the other (meth)acrylic monomer include a mono(meth)acrylic monomer (C) that is a mono(meth)acrylate other than the mono(meth)acrylic monomer (B).

[0084] The mono(meth)acrylic monomer (C) is a compound that contains one (meth)acryloyloxy group and does not contain any of the groups (b1) to (b13). That is, the mono(meth)acrylic monomer (C) is a mono(meth)acrylate that does not contain any of the groups (b1) to (b13). When the photocurable composition of the first embodiment contains the mono(meth)acrylic monomer (C), the photocurable composition of the first embodiment may contain only one type of mono(meth)acrylic monomer (C), or may contain two or more types of mono(meth)acrylic monomer (C).

[0085] The molecular weight of the mono(meth)acrylic monomer (C) is preferably 150 to 1,000, more preferably 150 to 400.

[0086] Specific examples of the mono(meth)acrylic monomer (C) include phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, m-phenoxybenzyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, isobornyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, and 4-tert-butylcyclohexyl (meth)acrylate. , tetrahydrofurfuryl (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, lauryl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-dodecyl-1-hexadecanyl (meth)acrylate, 2-(meth)acryloyloxyethyl succinic acid, 2-[[(butylamino)carbonyl]oxy]ethyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, and the like.

[0087] When the photocurable composition of the first embodiment contains the mono(meth)acrylic monomer (C), the content of the mono(meth)acrylic monomer (C) is preferably 50% by mass or less, more preferably 40% by mass or less, more preferably 30% by mass or less, and more preferably 20% by mass or less, based on the total amount of the photocurable composition for stereolithography. The photocurable composition of the first embodiment does not need to contain the mono(meth)acrylic monomer (C).

[0088] When the photocurable composition of the first embodiment contains the mono(meth)acrylic monomer (C), the content of the mono(meth)acrylic monomer (C) is preferably 50% by mass or less, more preferably 40% by mass or less, more preferably 30% by mass or less, and more preferably 20% by mass or less, relative to the total amount of (meth)acrylic monomers contained in the photocurable composition for stereolithography.

[0089] <Photopolymerization Initiator> The photocurable composition of the first embodiment contains at least one polymerization initiator. Examples of the polymerization initiator include general photopolymerization initiators used in the field of stereolithography. Examples of the photopolymerization initiator include alkylphenone compounds, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin compounds, acetophenone compounds, benzophenone compounds, thioxanthone compounds, α-acyloxime ester compounds, phenylglyoxylate compounds, benzyl compounds, azo compounds, diphenyl sulfide compounds, iron-phthalocyanine compounds, benzoin ether compounds, and anthraquinone compounds.

[0090] The photopolymerization initiator preferably includes at least one selected from the group consisting of alkylphenone compounds and acylphosphine oxide compounds. From the viewpoint of further improving the modeling accuracy of the stereolithography object, the photopolymerization initiator more preferably includes at least one selected from the group consisting of 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 1-hydroxy-cyclohexyl phenyl ketone, phenylglyoxylic acid methyl ester, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 1,2-octanedione, and 1-{4-(phenylthio)-, 2-(O-benzoyloxime)}.

[0091] The amount of the polymerization initiator contained in the photocurable composition is preferably 0.1% by mass to 20% by mass, more preferably 0.25% by mass to 10% by mass, and even more preferably 0.5% by mass to 5% by mass, relative to the total amount of the photocurable composition.

[0092] <Other Components> The photocurable composition of the first embodiment may contain other components in addition to the components described above, as necessary. Examples of other components include colorants, fillers, modifiers, stabilizers, antioxidants, solvents, resins, rubbers, etc.

[0093] From the viewpoint of further improving the modeling accuracy in photo-lithography, it is preferable that the photo-curable composition of the first embodiment does not contain an inorganic filler (e.g., silica, barium borosilicate glass, etc.; the same applies below), or, if it contains an inorganic filler, the content of the inorganic filler relative to the total amount of the photo-curable composition is 10% by mass or less (more preferably 5% by mass or less, even more preferably 2% by mass or less, and even more preferably 1% by mass or less).

[0094] <Preferred Viscosity of Photocurable Composition> From the viewpoint of handleability of the photocurable composition, the photocurable composition of the first embodiment preferably has a viscosity (hereinafter also simply referred to as "viscosity") measured with an E-type viscometer at 25°C and 50 rpm of 5 mPa s to 15,000 mPa s, and more preferably 5 mPa s to 10,000 mPa s. Here, rpm means revolutions per minute.

[0095] <Stereolithography> The photocurable composition of the first embodiment is a photocurable composition for stereolithography. That is, the photocurable composition of the first embodiment is a photocurable composition used for producing a three-dimensional object by stereolithography (hereinafter also referred to as a "stereolithography object").

[0096] Examples of the stereolithography method include a liquid tank method (for example, a DLP method or an SLA method, preferably a DLP method), an inkjet method, and the like.

[0097] In liquid vat-type stereolithography, a portion of a photocurable composition for stereolithography (i.e., an uncured photocurable composition in a liquid state; the same applies hereinafter) contained in a liquid vat is cured by light irradiation to form a cured layer, and this operation is repeated to stack cured layers, thereby obtaining a stereolithography object. Liquid vat-type stereolithography differs from inkjet-type stereolithography, which uses an inkjet nozzle, in that it uses a liquid vat. Liquid vat-type stereolithography is broadly divided into DLP (Digital Light Processing) stereolithography and SLA (Stereolithography) stereolithography. In the DLP method, planar light is irradiated onto the photocurable composition in the liquid vat. In the SLA method, laser light is scanned onto the photocurable composition in the liquid vat.

[0098] An example of DLP-based stereolithography uses a 3D printer (e.g., Kulzer's "Cara Print 4.0 pro," Asiga's "Max UV," etc.) equipped with: a build table movable in the vertical direction; a tray (i.e., a liquid tank) disposed below the build table (on the gravity side; the same applies below) that includes a light-transmitting portion and contains a photocurable composition; and a light source (e.g., an LED light source) disposed below the tray for irradiating the photocurable composition in the tray with planar light through the tray's light-transmitting portion. In this example, first, a gap of one layer is formed between the build table and the tray, and this gap is filled with photocurable composition. Next, planar light is irradiated from below through the tray's light-transmitting portion onto the photocurable composition filled in the gap, curing the irradiated area to form a first cured layer. Next, the gap between the build table and the tray is widened by the next layer, and the resulting space is filled with photocurable composition. Next, the photocurable composition that has filled the space is irradiated with light in the same manner as for curing the first layer to form a second cured layer. By repeating the above operation, cured layers are stacked to produce a three-dimensional object. In this example, the three-dimensional object may be further cured by further irradiating the produced three-dimensional object with light.

[0099] <Tear Strength> As described above, a cured product (e.g., a three-dimensional object) obtained by stereolithography using the photocurable composition of the first embodiment has excellent tear strength. For example, when the photocurable composition of the first embodiment is irradiated with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm, the cured product (e.g., a three-dimensional object) has excellent tear strength. ２ The cured layers A1 are laminated in the thickness direction to form a 100 μm thick cured layer A1, and a molded object A1 having a DIE C shape as defined in ASTM D 624 (2020) is formed. The molded object A1 is then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at an irradiation dose of 8252 J / cm at a wavelength of 405 nm. ２ When the tear strength of the test piece A1 is measured in accordance with ASTM D 624 (2020), the tear strength of the test piece A1 is preferably 10 N / mm to 300 N / mm, more preferably 100 N / mm to 300 N / mm. The tear strength of the test piece A1 may be 10 N / mm to 100 N / mm.

[0100] The tear strength of the above-described test piece A1 can be an indicator of the tear strength of a cured product (for example, a three-dimensional object) obtained by stereolithography using the photocurable composition of the first embodiment.

[0101] Here, the ASTM D 624 DIE C shape corresponds to the tear angle shape in JIS K 6252-1.

[0102] <Elongation at Break> As described above, a cured product (e.g., a three-dimensional object) obtained by stereolithography using the photocurable composition of the first embodiment has excellent elongation at break. For example, when the photocurable composition of the first embodiment is irradiated with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm, the cured product (e.g., a three-dimensional object) has excellent elongation at break. ２ The cured layers B1 are laminated in the thickness direction to form a 100 μm thick hardened layer B1, and a shaped object B1 having a No. 6 dumbbell shape as specified in JIS K 6251:2017 is formed. The hardened layer B1 is then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at an irradiation dose of 8252 J / cm at a wavelength of 405 nm. ２When the elongation at break of the test piece B1 is measured in accordance with JIS K 6251: 2017, the elongation at break of the test piece B1 is preferably 40% to 1000%, more preferably 40% to 800%. Note that the elongation at break of the test piece B1 may be 100% to 800%.

[0103] The elongation at break of the above-described test piece B1 can be an indicator of the elongation at break of a cured product (for example, a three-dimensional object) obtained by stereolithography using the photocurable composition of the first embodiment.

[0104] In measuring the elongation at break of test piece B1, the test piece was shaped like a No. 6 dumbbell, and the elongation at break was measured under test conditions of a test speed of 500±50 mm / min. The maximum measurement value among the values ​​measured under the test conditions was determined to be the elongation at break of test piece B1.

[0105] In the first embodiment, the tear strength of the above-mentioned test piece A1 may be 100 N / mm to 300 N / mm, and the elongation at break of the above-mentioned test piece B1 may be 40% to 800%. The first embodiment that satisfies these conditions is the second embodiment described below. In other words, the second embodiment described below is an embodiment that limits the first embodiment.

[0106] <Uses of Photocurable Composition> There are no particular limitations on the uses of the photocurable composition of the first embodiment. The photocurable composition of the first embodiment is preferably a photocurable composition used in the production of instruments used in the oral cavity, medical device components, denture bases, or surgical components (particularly preferably, the production of instruments used in the oral cavity).

[0107] Intraoral appliances include orthodontic retainers, night guards, sports mouthguards, bridges, implants, crowns, veneers, space maintainers, dental splints, dental inlays / onlays, dental attachments, dental resin bonding, and dental whitening trays. Medical device components include dental models, artificial heart valves, artificial legs, artificial hands, spinal fixation devices, catheters, stents, and osteoconduction implants. Denture bases include complete dentures, partial dentures, immediate dentures, overdentures, implant-supported dentures, and flexible partial dentures. Surgical components include artificial joints, external fixators, surgical guides, suction devices, plates and screws for fracture fixation, artificial joints, drain tubes, balloon catheters, stents, bioadhesives, and intervertebral disc prostheses.

[0108] <Three-dimensionally shaped object, instrument for intraoral use> The three-dimensionally shaped object of the first embodiment includes a cured product of the photocurable composition for stereolithography of the first embodiment. The cured product can be produced by the stereolithography described above. The instrument for intraoral use of the first embodiment includes the three-dimensionally shaped object of the first embodiment. The cured product of the photocurable composition for stereolithography of the first embodiment, the three-dimensionally shaped object of the first embodiment, and the instrument for intraoral use of the first embodiment are all produced using the photocurable composition for stereolithography of the first embodiment, and therefore have the same effects as the photocurable composition for stereolithography of the first embodiment (i.e., excellent in both tear strength and elongation at break).

[0109] Second Embodiment

[0110] <Photocurable Composition for Stereolithography> As described above, the photocurable composition for stereolithography of the second embodiment of the present disclosure is a photocurable composition for stereolithography of the first embodiment, limited to an embodiment in which the tear strength of the test piece A1 is 100 N / mm to 300 N / mm and the elongation at break of the test piece B1 is 40% to 800%. That is, the photocurable composition for stereolithography of the second embodiment of the present disclosure is a photocurable composition for stereolithography comprising: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of the groups (b1) to (b13); and a photopolymerization initiator, wherein the photocurable composition for stereolithography is irradiated with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm. ２ The cured layers A1 are laminated in the thickness direction to form a 100 μm thick cured layer A1, and a shaped object A1 having a DIE C shape as defined in ASTM D 624 (2020) is formed. The shaped object A1 is then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at a dose of 8252 J / cm at a wavelength of 405 nm. ２ A test piece A1 having the DIE C shape was prepared by irradiating the photocurable composition for stereolithography with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm. When the tear strength of the test piece A1 was measured in accordance with ASTM D 624 (2020), the tear strength of the test piece A1 was 100 N / mm to 300 N / mm. ２ The cured layers B1 are laminated in the thickness direction to form a 100 μm-thick hardened layer B1, and a shaped object B1 having a No. 6 dumbbell shape as specified in JIS K 6251:2017 is formed. The hardened layers B1 are then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at an irradiation dose of 8252 J / cm at a wavelength of 405 nm. ２and a dumbbell-shaped test piece B1 is prepared by irradiating the test piece B1 with an irradiation amount of 40% to 800% when the elongation at break of the test piece B1 is measured in accordance with JIS K 6251: 2017. The photocurable composition for stereolithography of the second embodiment may contain other components.

[0111] The photocurable composition for stereolithography of the second embodiment is suitable for obtaining a cured product (e.g., a three-dimensional object; the same applies below) that has excellent tear strength and elongation at break by stereolithography. That is, a cured product obtained by stereolithography using the photocurable composition for stereolithography of the second embodiment has excellent tear strength and elongation at break. The effect of the cured product having excellent tear strength and elongation at break is thought to be an effect obtained by combining the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B).

[0112] The photocurable composition for stereolithography of the second embodiment is the same as the photocurable composition for stereolithography of the first embodiment described above, except that it is limited to an embodiment in which the tear strength of the test piece A1 described above is 100 N / mm to 300 N / mm and the elongation at break of the test piece B1 described above is 40% to 800%, and therefore a duplicated description will be omitted.

[0113] <Three-dimensional object, instrument for use in the oral cavity> The three-dimensional object of the second embodiment is a cured product of the photocurable composition for stereolithography of the second embodiment. The three-dimensional object (cured product) of the second embodiment can be produced by the stereolithography described above in the first embodiment. The instrument for use in the oral cavity of the second embodiment includes the three-dimensional object of the second embodiment. The cured product of the photocurable composition for stereolithography of the second embodiment, the three-dimensional object of the second embodiment, and the instrument for use in the oral cavity of the second embodiment are all produced using the photocurable composition for stereolithography of the second embodiment, and therefore have the same effects as the photocurable composition for stereolithography of the second embodiment (i.e., excellent in both tear strength and elongation at break).

[0114] Examples of the first embodiment of the present disclosure will be described below, but the first embodiment is not limited to the following examples.

[0115] <Conditions for Nuclear Magnetic Resonance Spectroscopy (NMR)> In this example, NMR of (meth)acrylates other than KE1 to KE3 described below was carried out using the following equipment and analysis conditions. The measurement was carried out at 25°C using an AVANCE NEO cryo-500 nuclear magnetic resonance spectrometer manufactured by Bruker Biospin. The chemical shift reference was automatically set by the instrument. Each sample was dissolved in deuterated chloroform, １ H-NMR and １３ C-NMR measurements were carried out. DEPT measurements were carried out for UF-A7-52, UF-X9-83, Genomer 4277, and Ebecryl 8413. TOCSY, HSQC, and HMBC measurements were also carried out for UF-X9-83, Genomer 4277, and Ebecryl 8413. DEPT is 135°. TOCSY is J-bonded. １ HSQC is a two-dimensional measurement method that detects the spin network of H. １ Directly bonded to H １３ HMBC is a two-dimensional measurement method in which a correlation signal is detected between the １ The second or third bond from H １３ This is a two-dimensional measurement method in which a correlation signal is detected between KE1 and C. The NMR equipment and analysis conditions for KE1 to KE3 will be described later.

[0116] <Liquid Chromatography Mass Spectrometry (LC-MS) Conditions> In this example, LC-MS of (meth)acrylate was performed using the following equipment and analysis conditions: LC-MS equipment: ACQUITY UPLC H CLASS (manufactured by Waters Corporation) Column: ACQUITY UPLC BEH C18 1.7 μm 2.1 × 100 mm (manufactured by Waters Corporation) Flow rate: 0.5 ml / min Detection wavelength: 210 nm Mass spectrometry: electrospray spectrometry (ESI) Mobile phase: acetonitrile containing 0.1% by mass formic acid / water containing 0.1% by mass formic acid

[0117] Examples 1 to 24 and Comparative Examples 1 to 4 Preparation of Photocurable Compositions The materials shown in Tables 1 to 4 were mixed to prepare photocurable compositions of Examples 1 to 24 and Comparative Examples 1 to 4, respectively. Details of the materials shown in Tables 1 to 4 are as follows. The numerical values ​​shown in the columns for each component in Tables 1 to 4 indicate the amount (parts by mass) of each component. Blank columns in Tables 1 to 4 indicate that the corresponding component was not contained.

[0118] <Di(meth)acrylic monomer (A)>

[0119] UF-A7-52: (meth)acrylate containing the compound of the following structure as the main monomer (Kyoeisha Chemical Co., Ltd., a, b, and c are average degrees of polymerization (a, b = 3.2, c = 4.2), and n is 1 to 3). Here, "a, b = 3.2" means that the average of a and b is 3.2 (the same applies hereinafter).

[0120]

[0121] １ H-NMR and １３ In C-NMR, １ H-NMR (500MHz, CDCl ３ ): δ=0.90, 0.94, 1.03, 1.08, 1.21, 1.41, 1.56~1.71, 1.71~1.83, 2.94, 3.43, 3.60~3.87, 4.06, 4.15, 4.33, 4.36, 4.44-5.00, 5.88, 6.16, 6.45; １３ C-NMR (125MHz, CDCl ３ ​The spectrum of the main monomer was confirmed as follows: δ = 24.7, 27.1, 27.3-28.3, 29.1, 33.4, 36.6, 37.9, 42.7-49.5, 56.4, 63.6-64.8, 66.0, 69.2, 71.0-72.8, 129.6, 132.9, 156.8, 157.5, 158.0, 158.6, 167.4. TOCSY, HSQC, and HMBC spectra indicated the presence of polytetramethylene ether glycol (PTMG) units. From the correlation signal detected by HMBC, the connections between each unit were observed to be HEA (hydroxyethyl acrylate)-IPDI (isophorone diisocyanate), PTMG-IPDI, and polycarbonate containing PTMG. From these results, it was confirmed that the (meth)acrylate to be measured contains, as the main monomer, a compound in the above structure where a, b = 3.2, c = 4.2, and n = 1.

[0122] UF-X9-83: (meth)acrylate containing a compound having the following structure as the main monomer (Kyoeisha Chemical Co., Ltd., where a, b, and c are average degrees of polymerization (a, b = 3.1, c = 3.0), and n is 1 to 3).

[0123]

[0124] １ H-NMR and １３ In C-NMR, １ H-NMR (500MHz, CDCl ３ ): δ=0.60, 0.85, 1.25, 1.39, 1.49, 1.55, 1.58~1.71, 1.71~1.90, 3.04, 3.43, 4.07, 4.15, 4.31, 4.35, 4.59~5.64, 5.87, 6.16, 6.44; １３ C-NMR (125MHz, CDCl ３ ​The spectrum of the main monomer was confirmed as follows: δ = 22.2, 26.7, 27.1, 27.3-28.2, 30.7, 31.9, 33.3, 34.7, 36.0, 39.4, 46.5, 48.8, 49.5, 64.0, 64.3, 66.1, 69.2, 71.3-72.4, 129.6, 132.8, 156.8, 157.8, 157.9, 158.4, 167.4. From these results, it was confirmed that the (meth)acrylate to be measured contained, as the main monomer, a compound in which a, b = 3.1, c = 3.0, and n = 1 in the above structure.

[0125] EKSP-1: A (meth)acrylate containing a compound having the following structure (a compound produced according to Production Example 1 described later. a, b, and c are average degrees of polymerization, a and b are each independently an integer of 1 to 10, and at least one of a and b is 2 or greater, c is an integer of 1 to 10, and n is an integer of 1 to 10.

[0126]

[0127] Genomer 4277: A (meth)acrylate containing a compound having the following structure as a main monomer (Rahn AG, n and m are average degrees of polymerization, n is each independently an integer of 2 to 10, and m is an integer of 1 to 10).

[0128]

[0129] １ H-NMR and １３ In C-NMR, １ H-NMR (500MHz, CDCl ３ ): δ=0.90, 0.95, 1.04, 1.08, 1.22, 1.25, 1.41, 1.58~1.82, 1.89, 1.97, 2.38, 2.94, 3.70, 3.82, 3.95~4.22, 4.24, 4.34, 4.46-4.95, 5.02, 5.14, 5.61, 6.15; １３ C-NMR (125MHz, CDCl ３ ​The main monomers were identified as follows: δ = 16.1-17.1, 18.3, 23.2, 24.2, 27.6, 31.8, 33.2-34.2, 35.0, 36.4, 41.1-48.6, 54.9, 61.7-70.0, 126.0, 136.0, 154.8-156.0, 156.0-157.0, 167.1, 172.4-173.6. TOCSY, HSQC, and HMBC spectra indicated the presence of diethylene glycol (DEG), propylene glycol (PG), and adipic acid (AA) as units. From the correlation signal detected by HMBC, HEMA-IPDI, PG-IPDI (isophorone diisocyanate), DEG-IPDI, PG-AA, and DEG-AA were observed as connections between the individual units.

[0130] UF-0146: (meth)acrylate containing two (meth)acryloyloxy groups and at least one urethane bond (Kyoeisha Chemical Co., Ltd.)

[0131] UF-754EX-20POB: (meth)acrylate containing two (meth)acryloyloxy groups and at least one urethane bond and carbonate bond, containing 20% ​​by mass of m-phenoxybenzyl acrylate as a diluent monomer (Kyoeisha Chemical Co., Ltd.)

[0132] Ebecryl 8413: (meth)acrylate containing the main monomer of the following structure (Allnex, n is the average degree of polymerization, and m is 1 to 3) (contains isobornyl acrylate as a diluent monomer)

[0133]

[0134] １ H-NMR and １３ In C-NMR, １ H-NMR (500MHz, CDCl ３ ​): δ= 0.88~1.10, 1.33~1.53, 1.63, 1.67, 1.82, 2.33, 2.93, 3.42, 3.61~3.90, 4.07, 4.30, 4.36, 4.48~4.95, 5.88, 6.16, 6.45, 7.55, 8.23, 8.68; １３ C-NMR (125MHz, CDCl ３ The main monomers were identified as follows: δ = 23.2, 24.4, 25.2-26.0, 26.5, 27.6, 28.3-29.1, 31.8, 33.9, 35.0, 36.3, 41.5-47.7, 54.8, 61.9-65.0, 64.3, 65.2, 70.6, 128.1, 128.6, 130.6, 130.8, 131.3, 133.7, 155.2-157.2, 165.8, 165.9, 173.4. In addition, the peaks derived from isobornyl acrylate used as a diluent monomer were １ H-NMR (500MHz, CDCl ３ ): δ=0.86, 0.87, 1.02, 1.08~1.24, 1.53~2.03, 4.76, 5.80, 6.10, 6.35; １３ C-NMR (125MHz, CDCl ３ The peaks were confirmed as follows: δ = 11.4, 19.9, 20.1, 27.0, 33.7, 38.7, 45.0, 46.9, 48.8, 81.1, 129.2, 130.0, 165.7; TOCSY, HSQC, and HMBC spectra revealed the presence of polytetramethylene ether glycol (PTMG) skeletons, 1,6-hexanediol (1,6-HD) skeletons, and adipic acid (AA) skeletons as units. From the correlation signals detected by HMBC, the connections between each unit were observed to be HEA-IPDI (isophorone diisocyanate), PTMG-IPDI, 1,6-HD-IPA (isophthalic acid), and 1,6-HD-AA.

[0135] <Mono(meth)acrylic monomer (B)>

[0136] Viscoat #200: Cyclic trimethylolpropane formal acrylate having the following structure (Osaka Organic Chemicals Co., Ltd., molecular weight 200.2)

[0137]

[0138] Viscoat #200M: Cyclic trimethylolpropane formal methacrylate having the following structure (Osaka Organic Chemical Co., Ltd., molecular weight 214.2)

[0139]

[0140] <Mono(meth)acrylic monomer (C)>

[0141] SR423NS: Isobornyl methacrylate having the following structure (Arkema, molecular weight: 222.3)

[0142]

[0143] IBXA: isobornyl acrylate having the following structure (Osaka Organic Chemicals Co., Ltd., molecular weight 208.3)

[0144]

[0145] CHDMMA: 1,4-cyclohexanedimethanol monoacrylate having the following structure (Mitsubishi Chemical Corporation, molecular weight 198)

[0146]

[0147] POB-A: m-phenoxybenzyl acrylate having the following structure (Kyoeisha Chemical Co., Ltd., molecular weight 254.3)

[0148]

[0149] <Photopolymerization initiator> Omnirad TPO: an acylphosphine oxide compound having the following structure (IGM RESINS)

[0150]

[0151] Omnirad 819: an acylphosphine oxide compound having the following structure (IGM RESINS)

[0152]

[0153] <Production Example 1: Production of EKSP-1> Into a 0.3-liter four-neck flask equipped with a thoroughly dried stirring blade and a thermometer, 50.25 g (0.05 mol) of polyether polycarbonate diol (PEPCD NT1002, constituent monomer PTMG250, molecular weight 1000, manufactured by Mitsubishi Chemical Corporation) and 20.01 g (0.09 mol) of IPDI (isophorone diisocyanate) were charged and stirred at 60 ° C. for 10 minutes. The mixture was then cooled to 30 ° C., and 0.0798 g (1000 ppm) of DBTDL (dibutyltin dilaurate) was added dropwise using a micropipette. After the entire amount was added, it was confirmed that the temperature of the flask was constant, and the mixture was stirred at 80 ° C. for 2 hours. Thereafter, 0.1596 g (2000 ppm) of BHT (dibutylhydroxytoluene) was added, and 9.522 g (0.082 mol) of hydroxyethyl acrylate (HEA) added to a separate dropping funnel was added dropwise over 30 minutes. Since the internal temperature rose due to the heat of reaction during the dropwise addition, the amount added was controlled so that it was 100 ° C or less. After the entire amount was added dropwise, the reaction temperature was maintained at 95 ° C, and the reaction was carried out for 2 hours and 30 minutes. By discharging the product from the reactor, 62.4 g of (meth)acrylate (EKSP-1) was obtained. The viscosity at 80 ° C was 4.63 Pa s. The reaction was carried out while tracking the progress of the reaction by liquid chromatography mass spectrometry (LC-MS), and the end point of the reaction was confirmed. In the LC-MS analysis, the EKSP-1 peak was detected between retention times of 12.5 and 20.9 minutes, and the ratio (X / Y) of the EKSP-1 peak area X to the HEA peak area Y was 12.5. The detected peaks had a molecular weight of 1431 as [M+H] for a, b = 3, c = 2, n = 1, and a molecular weight of 1692 as [M+H] for a, b = 3, c = 3, n = 1.

[0154] <Measurement of Molecular Weight of Di(meth)acrylic Monomer (A)> For each di(meth)acrylic monomer (A) (i.e., UF-A7-52, UF-X9-83, EKSP-1, Genomer 4277, UF-0146, UF-754EX-20POB, and Ebecryl 8413), the weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight (more specifically, the range of molecular weights of the compounds contained in each di(meth)acrylic monomer (A)) were measured by gel permeation chromatography (GPC). The lower and upper limits of the molecular weight range were determined as follows. Within the molecular weight range of the di(meth)acrylic monomer (A) measured by GPC analysis, the upper limit was set to the molecular weight excluding the upper 5% area range, and the lower limit was set to the molecular weight excluding the lower 5% area range, with the total molecular weight area of ​​the di(meth)acrylic monomer (A) being taken as 100%. For UF-754EX-20POB and Ebecryl 8413, the Mw, Mn, and molecular weight ranges are given for the components excluding any diluent monomers present (ie, the major monomers).

[0155] GPC for measuring molecular weight was performed using the following equipment, pretreatment method, and analysis conditions. The results are shown in Tables 1 to 4. Tables 1 to 4 also show the molecular weights of components other than the di(meth)acrylic monomer (A). The molecular weights of components other than the di(meth)acrylic monomer (A) are shown as molecular weights derived from the chemical structure of each component (i.e., each compound).

[0156] (Apparatus) 515 HPLC pump (used with Genomer 4277), KP-22-13S dual pump (used with UF-A7-52, UF-X9-83, EKSP-1, UF-0146, UF-754EX-20POB, and Ebecryl 8413), 717plus automatic injection device (Nihon Waters), RI-101 differential refractive index detector (Shodex)

[0157] (Pretreatment method) A sample was weighed into a 30 mL vial, and 3.0 mL of mobile phase for GPC measurement was added per 3.0 mg of sample. The vial was then sealed and left to stand overnight to dissolve. The solution was filtered through a 0.45 μm hydrophilic PTFE membrane filter cartridge (Millex-LCR 33 mm; Merck), and the filtrate was used for measurement.

[0158] (Analysis conditions) Column / Temperature: 2x PLgel 3 μm MIXED-E, 7.5 x 300 mm (Agilent Technologies) / 40°C Mobile phase: HPLC-grade tetrahydrofuran [stabilizer included] (Fujifilm Wako Pure Chemical Industries) Flow rate: 1.0 mL / min. Injection volume: 100 μL Detection: RI (Refractive Index) Column calibration: Monodisperse PS; EasiVial PS-L polystyrene (Agilent Technologies) Molecular weight calibration: Relative calibration method (PS equivalent)

[0159] <Measurement of Viscosity of Photocurable Composition> The viscosity of the resulting photocurable composition was measured using an E-type viscometer at 25° C. and 50 rpm. The results are shown in Tables 1 to 4.

[0160] <Evaluation of Elongation at Break of Cured Product (Test Piece B1)> Using the obtained photocurable composition, a dumbbell-shaped No. 6 shaped object B1 (layer width (i.e., thickness of cured layer B1) 100 μm) was produced by stereolithography in accordance with JIS K 6251:2017. Stereolithography was performed using a 3D printer (Kulzer, Cara Print 4.0 pro) using visible light with a wavelength of 385 nm at an irradiation dose of 22 mJ / cm. ２ The DLP method was carried out under the conditions of 1. Next, the obtained object B1 was immersed in isopropanol, washed for 5 minutes using an ultrasonic cleaner with an output of 60 W, and dried with an air blower. Thereafter, it was cured for 10 minutes (irradiation dose 8252 J / cm) using a post-curing device (Kulzer, Highlight Power 3D) with a main spectrum of wavelengths from 390 nm to 540 nm. ２ The shaped object B1 was irradiated with light to fully cure the object B1, thereby obtaining a cured product, a test piece B1. The irradiation dose was measured using an ultraviolet integrating actinometer (Ushio Inc., UIT-250) at a light receiving section with a measurement wavelength of 405 nm.

[0161] The elongation at break of the obtained test piece B1 was measured under the following test conditions. - Test conditions - (Apparatus) EZ-SX (manufactured by Shimadzu Corporation) (Test piece B1 shape) Dumbbell-shaped No. 6 (Grip distance) 50 mm (Test speed) 500 ± 50 mm / min (Measurement temperature) 23°C (Method of calculating elongation at break) Distance (mm) elongated until test piece breaks / Grip distance (mm)

[0162] The above measurement was carried out five times, and the maximum value among the measured values ​​was determined as the elongation at break of the test piece. The results are shown in Tables 1 to 4.

[0163] (Evaluation of tear strength of cured product (test piece A1)) Using the obtained photocurable composition, a shaped product A1 (layer width 100 μm) in an ASTM D 624 DIE C shape (i.e., JIS K 6252-1 tear angle shape) was produced by stereolithography. Stereolithography was performed using a 3D printer (Cara Print 4.0 pro) with visible light of 385 nm wavelength at an irradiation dose of 22 mJ / cm. ２ The DLP method was carried out under the conditions of 1. Next, the obtained shaped object A1 was immersed in isopropanol, washed for 5 minutes using an ultrasonic cleaner with an output of 60 W, and dried with an air blower. Thereafter, it was cured for 10 minutes (irradiation dose 8252 J / cm) using a post-curing device (Kulzer, Highlight Power 3D) with a main spectrum of wavelengths from 390 nm to 540 nm. ２ ) light was irradiated to the shaped object A1, and the shaped object A1 was fully cured to obtain a test piece A1 as a cured product. The irradiation dose was measured using an ultraviolet integrating actinometer (Ushio Inc., UIT-250) at a light receiving section with a measurement wavelength of 405 nm. The tear strength of the obtained test piece was measured under the following test conditions: (Apparatus) Universal testing machine (INTESCO Corporation) (Shape of test piece A1) ASTM D 624 DIE C shape (Grip distance) 75 mm (Test speed) 500±50 mm / min (Measurement temperature) 23°C (Method of calculating tear strength) Maximum tear force (N) / Median thickness of test piece (mm) The above measurement was performed five times, and the maximum of the measured values ​​was determined to be the tear strength of the test piece.

[0164]

[0165]

[0166]

[0167]

[0168] As shown in Tables 1 to 4, the cured products (test pieces) of Examples 1 to 24 obtained using photocurable compositions containing: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of groups (b1) to (b13); and a photopolymerization initiator were excellent in both tear strength and elongation at break. In contrast, the cured products of Comparative Examples 1 to 4 obtained using photocurable compositions not containing either the di(meth)acrylic monomer (A) or the mono(meth)acrylic monomer (B) showed decreased at least one of tear strength and elongation at break.

[0169] Example 25 A photocurable composition according to Example 25 was prepared by mixing 20 parts by mass of Ebecryl 8413 as the di(meth)acrylic monomer (A), 62.98 parts by mass of Viscoat #200 as the mono(meth)acrylic monomer (B), and 2 parts by mass of TPO as a photopolymerization initiator. For the photocurable composition according to Example 25, "measurement of the viscosity of the photocurable composition," "evaluation of the elongation at break of the cured product (test piece B1)," and "evaluation of the tear strength of the cured product (test piece A1)" were carried out in the same manner as for the photocurable compositions according to Examples 1 to 24 and Comparative Examples 1 to 4. As a result, for the cured product of the photocurable composition according to Example 25, the elongation at break was in the range of 250 to 350%, the tear strength was 67.8 N / mm, and the viscosity of the photocurable composition was 389 mPa s.

[0170] Example 26 A photocurable composition according to Example 26 was prepared by mixing 20 parts by mass of Ebecryl 8413 as the di(meth)acrylic monomer (A), 20 parts by mass of Viscoat #200 as the mono(meth)acrylic monomer (B), and 2 parts by mass of TPO as a photopolymerization initiator. For the photocurable composition according to Example 26, "measurement of the viscosity of the photocurable composition," "evaluation of the elongation at break of the cured product (test piece B1)," and "evaluation of the tear strength of the cured product (test piece A1)" were carried out in the same manner as for the photocurable compositions according to Examples 1 to 24 and Comparative Examples 1 to 4. As a result, for the cured product of the photocurable composition according to Example 26, the elongation at break was in the range of 300 to 450%, the tear strength was 33.2 N / mm, and the viscosity of the photocurable composition was 5,340 mPa·s.

[0171] Example 27 A photocurable composition according to Example 27 was prepared by mixing 55 parts by mass of Ebecryl 8413 as the di(meth)acrylic monomer (A), 45 parts by mass of Viscoat #200 as the mono(meth)acrylic monomer (B), and 2 parts by mass of TPO as a photopolymerization initiator. For the photocurable composition according to Example 27, "measurement of the viscosity of the photocurable composition," "evaluation of the elongation at break of the cured product (test piece B1)," and "evaluation of the tear strength of the cured product (test piece A1)" were carried out in the same manner as for the photocurable compositions according to Examples 1 to 24 and Comparative Examples 1 to 4. As a result, for the cured product of the photocurable composition according to Example 27, the elongation at break was in the range of 300 to 450%, the tear strength was 35.0 N / mm, and the viscosity of the photocurable composition was 7930 mPa s.

[0172] Example 28 A photocurable composition according to Example 28 was prepared by mixing 20 parts by mass of Ebecryl 8413 as the di(meth)acrylic monomer (A), 50.38 parts by mass of Viscoat #200 as the mono(meth)acrylic monomer (B), 12.47 parts by mass of CHDMMA, and 2 parts by mass of TPO as a photopolymerization initiator. For the photocurable composition according to Example 28, "measurement of the viscosity of the photocurable composition," "evaluation of the elongation at break of the cured product (test piece B1)," and "evaluation of the tear strength of the cured product (test piece A1)" were carried out in the same manner as for the photocurable compositions according to Examples 1 to 24 and Comparative Examples 1 to 4. As a result, for the cured product of the photocurable composition according to Example 28, the elongation at break was in the range of 200 to 300%, the tear strength was 50.8 N / mm, and the viscosity of the photocurable composition was 185 mPa s.

[0173] Examples 29 to 35 Preparation of Photocurable Compositions The materials shown in Table 5 were mixed to prepare the photocurable compositions of Examples 29 to 35. Details of the materials shown in Table 5 are as follows. The numerical value shown in the column for each component in Table 5 indicates the amount (parts by mass) of each component. A blank column in Table 5 means that the corresponding component was not contained.

[0174] <Di(meth)acrylic monomer (A)> Ebecryl 270: a (meth)acrylate containing a compound having the following structure as the main monomer (Allnex Corporation; in the following structure, n is 1 to 3, and m is 1 to 3).

[0175]

[0176] Genomer 4277: See the descriptions in the above Examples 1 to 24. Ebecryl 8413: See the descriptions in the above Examples 1 to 24.

[0177] <Mono(meth)acrylic monomer (B)> Viscoat #200: See the descriptions in the above Examples 1 to 24. KE1: The following compound produced according to Production Example 2 described below. KE2: The following compound produced according to Production Example 3 described below. KE3: The following compound produced according to Production Example 4 described below.

[0178]

[0179] The following for KE1, KE2, and KE3 １ H-NMR measurements were carried out by dissolving each of the samples KE1, KE2, and KE3 in deuterated methanol. １ The H-NMR measurement was performed using a JNM-ECZ400S / L1 nuclear magnetic resonance spectrometer manufactured by JEOL Ltd. Measurements were performed at 25° C. The chemical shift reference was automatically set by the instrument.

[0180] (Production Example 2: Production of KE1) 18.3 g (0.125 mol) of (2,2-dimethyl-1,3-dioxan-5-yl)methanol, 26.9 g (0.31 mol) of methyl acrylate, 6.0 g of n-hexane, and 0.204 g (4000 ppm) of MEHQ (p-methoxyphenol) were charged into a 0.5-liter three-neck flask equipped with a thoroughly dried stirrer and a thermometer, and stirred at room temperature for 5 minutes. The mixture was then cooled to 30°C, and 0.102 g (2000 ppm) of dioctyltin oxide was added dropwise using a micropipette. After the entire amount was added, it was confirmed that the temperature of the flask was constant, and the mixture was stirred at 70-75°C for 8 hours, and then stirred at room temperature for 8 hours. After the reaction, a condenser, a 100 ml recovery flask, and glass tubes connecting the reactor, condenser, and recovery flask were prepared, and a distillation system was prepared. Thereafter, 0.102 g (2000 ppm) of dioctyltin oxide was added dropwise to the reactor using a micropipette, and dry air was blown onto the liquid surface at a pressure adjusted to 0.1 kPa. The mixture was stirred for 8 hours at 75-80°C. The progress of the reaction was monitored using a TLC plate (developing solvent: hexane / ethyl acetate = 4 / 1 (mass ratio)), and the disappearance of the raw materials was taken as the end point of the reaction. The product was discharged from the reactor, concentrated using an evaporator, and subjected to column chromatography using hexane / ethyl acetate = 4 / 1 (mass ratio), yielding 7.01 g of the target product, (2,2-dimethyl-1,3-dioxan-5-yl) methyl acrylate (KE1). １ In H-NMR, １ H-NMR (400MHz, CD ３The spectrum of the major monomer was confirmed as follows: δ = 1.38, 1.42, 2.00-2.04, 3.76, 4.04, 4.25, 5.90, 6.17, 6.39; OD).

[0181] (Production Example 3: Production of KE2) 80.1 g (0.50 mol) of (2,2,5-Trimethyl-1,3-dioxan-5-yl)methanol, 129.1 g (1.50 mol) of methyl acrylate, 24.0 g of n-hexane, and 0.466 g (2000 ppm) of MEHQ (p-methoxyphenol) were charged into a 0.5-liter three-neck flask equipped with a thoroughly dried stirrer and a thermometer, and the mixture was stirred at room temperature for 5 minutes. The mixture was then cooled to 30°C, and 0.466 g (2000 ppm) of dioctyltin oxide was added dropwise using a micropipette. After the entire amount was added, it was confirmed that the temperature of the flask was constant, and the mixture was stirred at 70-75°C for 8 hours, followed by stirring at room temperature for 8 hours. After the reaction, a condenser, a 100 ml recovery flask, and a glass tube connecting the reactor, recovery flask, and recovery flask were prepared to form a distillation system. Then, 0.466 g (2000 ppm) of dioctyltin oxide was added dropwise to the reactor using a micropipette, and dry air was blown onto the liquid surface at a pressure adjusted to 0.1 kPa. The mixture was stirred at 75-80°C for 8 hours. The progress of the reaction was monitored using a TLC plate (developing solvent: hexane / ethyl acetate = 4 / 1 (mass ratio)), and the disappearance of the raw materials was taken as the end point of the reaction. The product was discharged from the reactor, concentrated using an evaporator, and subjected to column chromatography using hexane / ethyl acetate = 4 / 1 (mass ratio). 35.2 g of the target product, (2,2,5-trimethyl-1,3-dioxan-5-yl) methyl acrylate (KE2), was obtained. １ In H-NMR, １ The spectrum of the main monomer was confirmed by H-NMR (400 MHz, CD3OD): δ = 0.88, 1.35, 1.43, 3.64-3.71, 4.23, 5.90, 6.19, 6.40.

[0182] (Production Example 4: Production of KE3) 15.0 g (0.15 mol) of tetrahydro-4-pyranol, 18.0 g (0.18 mol) of triethylamine, and 150 ml of DCM (dichloromethane) were charged into a 0.5-liter three-neck flask equipped with a thoroughly dried stirrer and a thermometer, and stirred at room temperature for 5 minutes. The mixture was then cooled to 0°C, and 18.0 g (0.20 mol) of acryloyl chloride was added dropwise using a dropping funnel over 15 minutes. After the entire amount was added, it was confirmed that the temperature of the flask was constant, and the mixture was stirred at room temperature for 8 hours. The progress of the reaction was monitored using a TLC plate (developing solvent: hexane / ethyl acetate = 3 / 1 (mass ratio)), and the disappearance of the raw materials was taken as the end point of the reaction. After the reaction, saturated NaHCO ３ A quenching treatment was carried out using about 200 ml of aq (aqueous sodium bicarbonate solution). After the quenching treatment, about 300 ml of ethyl acetate was added, and a liquid separation treatment was carried out. The resulting product was concentrated using an evaporator, and then subjected to column chromatography using hexane / ethyl acetate = 3 / 1 (mass ratio) to obtain 20.1 g of the target product, tetrahydro-2H-pyran-4-yl acrylate (KE3). １ In H-NMR, １ The spectrum of the main monomer was confirmed by H-NMR (400 MHz, CD3OD): δ = 1.64-1.73, 1.92-1.98, 3.57, 3.91, 5.01, 5.89, 6.16, 6.39.

[0183] <Mono(meth)acrylic monomer (C)> IBXA: See the descriptions in the above Examples 1 to 24. 2-HBMA: 2-hydroxybutyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) POB-A: See the descriptions in the above Examples 1 to 24.

[0184] <Photopolymerization initiator> Omnirad TPO: See the descriptions in the above Examples 1 to 24. Omnirad 819: See the descriptions in the above Examples 1 to 24.

[0185] <Measurement of Molecular Weight of Di(meth)acrylic Monomer (A)> The descriptions in the explanation of Examples 1 to 24 above can be referred to.

[0186] The explanations in the examples of the first embodiment can also be referred to for the apparatus, pretreatment method, and analysis conditions used in GPC to measure molecular weight. The results are shown in Table 5. Table 5 also shows the molecular weights of components other than the di(meth)acrylic monomer (A). The molecular weights of components other than the di(meth)acrylic monomer (A) are shown as molecular weights derived from the chemical structure of each component (i.e., each compound).

[0187] <Measurement of Viscosity of Photocurable Composition> The viscosity of the obtained photocurable composition was measured using an E-type viscometer at 25° C. and 50 rpm. The results are shown in Table 5.

[0188] <Evaluation of Elongation at Break of Cured Product (Test Piece B1)> Using the obtained photocurable composition, a test piece B1 was prepared as a cured product of this photocurable composition, and the elongation at break of the obtained test piece B1 was evaluated. For the method for producing test piece B1 and the method for evaluating the elongation at break, please refer to the descriptions in the above-mentioned Examples 1 to 24. The results are shown in Table 5.

[0189] <Evaluation of tear strength of cured product (test piece A1)> Using the obtained photocurable composition, a test piece A1 was prepared as a cured product of this photocurable composition, and the tear strength of the obtained test piece A1 was evaluated. For the method of producing test piece A1 and the method of evaluating its tear strength, please refer to the descriptions in the above-mentioned Examples 1 to 24. The results are shown in Table 5.

[0190]

[0191] As shown in Table 5, the cured products (test specimens) of Examples 29 to 35 obtained using the photocurable compositions containing the di(meth)acrylic monomer (A), the mono(meth)acrylic monomer (B), and the photopolymerization initiator were also excellent in both tear strength and elongation at break, similar to the cured products (test specimens) of Examples 1 to 28.

[0192] Next, examples of the second embodiment will be described, but the second embodiment is not limited to the following examples.

[0193] Examples 101 to 117 and Comparative Examples 101 to 103 Preparation of Photocurable Compositions The materials shown in Tables 6 to 8 were mixed to prepare photocurable compositions of Examples 101 to 117 and Comparative Examples 101 to 103, respectively. Details of the materials shown in Tables 6 to 8 are as follows. The numerical values ​​shown in the columns for each component in Tables 6 to 8 indicate the amount (parts by mass) of each component. Blank columns in Tables 6 to 8 indicate that the corresponding component was not contained.

[0194] <Di(meth)acrylic monomer (A)> UF-A7-52: Please refer to the descriptions in the above Examples 1 to 24. UF-X9-83: Please refer to the descriptions in the above Examples 1 to 24. EKSP-1: Please refer to the descriptions in the above Examples 1 to 24. Genomer 4277: Please refer to the descriptions in the above Examples 1 to 24. UF-0146: Please refer to the descriptions in the above Examples 1 to 24.

[0195] <Mono(meth)acrylic monomer (B)> Viscoat #200: See the descriptions in the above Examples 1 to 24. Viscoat #200M: See the descriptions in the above Examples 1 to 24.

[0196] <Mono(meth)acrylic monomer (C)> SR423NS: See the descriptions in the above Examples 1 to 24. IBXA: See the descriptions in the above Examples 1 to 24. POB-A: See the descriptions in the above Examples 1 to 24.

[0197] <Photopolymerization initiator> Omnirad TPO: See the descriptions in the above Examples 1 to 24. Omnirad 819: See the descriptions in the above Examples 1 to 24.

[0198] <Measurement of Molecular Weight of Di(meth)acrylic Monomer (A)> The descriptions in the explanation of Examples 1 to 24 above can be referred to.

[0199] The descriptions in the above Examples 1 to 24 can also be referred to for the apparatus, pretreatment method, and analysis conditions used in GPC to measure molecular weight. The results are shown in Tables 6 to 8. Tables 6 to 8 also show the molecular weights of components other than the di(meth)acrylic monomer (A). The molecular weights of components other than the di(meth)acrylic monomer (A) are molecular weights derived from the chemical structure of each component (i.e., each compound).

[0200] <Measurement of Viscosity of Photocurable Composition> The viscosity of the obtained photocurable composition was measured using an E-type viscometer at 25° C. and 50 rpm. The results are shown in Tables 6 to 8.

[0201] <Evaluation of Elongation at Break of Cured Product (Test Piece B1)> Using the obtained photocurable composition, test pieces B1 were prepared as cured products of the photocurable composition, and the elongation at break of the obtained test pieces B1 was evaluated. For the method for producing test pieces B1 and the method for evaluating the elongation at break, see the descriptions in the above-mentioned Examples 1 to 24. The results are shown in Tables 6 to 8.

[0202] <Evaluation of tear strength of cured product (test piece A1)> Using the obtained photocurable composition, a test piece A1 was prepared as a cured product of this photocurable composition, and the tear strength of the obtained test piece A1 was evaluated. For the method of producing test piece A1 and the method of evaluating its tear strength, please refer to the descriptions in the above-mentioned Examples 1 to 24. The results are shown in Tables 6 to 8.

[0203]

[0204]

[0205]

[0206] As shown in Tables 6 to 8, the cured products (test specimens) of Examples 101 to 117 obtained using photocurable compositions containing: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of groups (b1) to (b13); and a photopolymerization initiator were excellent in both tear strength and elongation at break. Specifically, in Examples 101 to 117, the tear strength of test specimen A1 was 100 N / mm to 300 N / mm, and the elongation at break of test specimen B1 was 40% to 800%. In contrast, the cured products of Comparative Examples 101 to 103 obtained using photocurable compositions that did not contain either the di(meth)acrylic monomer (A) or the mono(meth)acrylic monomer (B) exhibited reduced tear strength and / or elongation at break. Specifically, Comparative Examples 101 to 103 did not satisfy the requirements that the tear strength of test piece A1 be 100 N / mm to 300 N / mm and the elongation at break of test piece B1 be 40% to 800%.

[0207] The disclosures of Japanese Patent Application Nos. 2024-089338, filed on May 31, 2024, and 2024-089339, filed on May 31, 2024, are incorporated herein by reference in their entirety. All documents, patent applications, and technical standards described herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A photocurable composition for stereolithography, comprising: a di(meth)acrylic monomer (A) containing two (meth)acryloyloxy groups; a mono(meth)acrylic monomer (B) containing one (meth)acryloyloxy group and at least one selected from the group consisting of the following groups (b1) to (b13); and a photopolymerization initiator. [In group (b1), R ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ any one of R is a divalent hydrocarbon group; ｂ１Ａ , R ｂ１Ｂ , R ｂ１Ｃ , R ｂ１Ｄ , R ｂ１Ｅ , R ｂ１Ｆ , and R ｂ１Ｇ The remainder of the groups (b2) are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ２Ａ and R ｂ２Ｂ one of which is a divalent hydrocarbon group, and R ｂ２Ａ and R ｂ２Ｂ the other is a hydrogen atom or a monovalent hydrocarbon group, and R ｂ２Ｃ and R ｂ２Ｄ are each independently a hydrogen atom or a monovalent hydrocarbon group. ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ any one of R is a divalent hydrocarbon group; ｂ３Ａ , R ｂ３Ｂ , R ｂ３Ｃ , R ｂ３Ｄ , R ｂ３Ｅ , R ｂ３Ｆ , R ｂ３Ｇ , R ｂ３Ｈ , and R ｂ３Ｉ The remainders of each of the groups are independently a hydrogen atom or a monovalent hydrocarbon group, and the double line consisting of a solid line and a dashed line represents a single bond or a double bond. In the group (b4), * represents the bonding position. In the group (b5), R ｂ５Ａ , R ｂ５Ｂ , and R ｂ５Ｃ are each independently a monovalent hydrocarbon group which may have an oxo group as a substituent, and R ｂ５Ｄ and R ｂ５Ｅ are each independently a hydrogen atom or a monovalent hydrocarbon group, or R ｂ５Ｄ and R ｂ５Ｅ together form an oxo group, R ｂ５Ｆ is a hydrogen atom or a monovalent hydrocarbon group, R ｂ５Ｇ and R ｂ５Ｈ are each independently a hydrogen atom or a monovalent hydrocarbon group which may have an alkoxy group as a substituent, or R ｂ５Ｇ and R ｂ５Ｈ together form an oxo group, and * indicates the bonding position. In groups (b6) to (b13), * indicates the bonding position.

2. The photocurable composition for stereolithography according to claim 1, wherein the molecular weight of the di(meth)acrylic monomer (A) is 500 to 100,000.

3. The photocurable composition for stereolithography according to claim 1, wherein the molecular weight of the mono(meth)acrylic monomer (B) is 150 to 400.

4. The photocurable composition for stereolithography according to claim 1, wherein the content of the di(meth)acrylic monomer (A) is 5% by mass to 85% by mass relative to the total amount of the photocurable composition for stereolithography.

5. The photocurable composition for stereolithography according to claim 1, wherein the content of the mono(meth)acrylic monomer (B) is 10% by mass to 95% by mass relative to the total amount of the photocurable composition for stereolithography.

6. The photocurable composition for stereolithography according to claim 1, wherein the content of the mono(meth)acrylic monomer (B) is 15% by mass to 49% by mass relative to the total amount of the photocurable composition for stereolithography.

7. A photocurable composition for photopolymerization according to claim 1, wherein the total content of the di(meth)acrylic monomer (A) and the mono(meth)acrylic monomer (B) is 60 mass% or more relative to the total amount of the photocurable composition for photopolymerization.

8. The photocurable composition for stereolithography was irradiated with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm ２ The cured layers A1 are laminated in the thickness direction to form a 100 μm thick cured layer A1, and a shaped object A1 having a DIE C shape as defined in ASTM D 624 (2020) is formed. The shaped object A1 is then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at a dose of 8252 J / cm at a wavelength of 405 nm. ２ A test piece A1 having the DIE C shape was prepared by irradiating the photocurable composition for stereolithography with visible light having a wavelength of 385 nm at an irradiation dose of 22 mJ / cm. When the tear strength of the test piece A1 was measured in accordance with ASTM D 624 (2020), the tear strength of the test piece A1 was 10 N / mm to 300 N / mm. ２ The cured layers B1 are laminated in the thickness direction to form a 100 μm-thick hardened layer B1, and a shaped object B1 having a No. 6 dumbbell shape as specified in JIS K 6251:2017 is formed. The hardened layers B1 are then irradiated with ultraviolet light having a wavelength of 390 nm to 540 nm at an irradiation dose of 8252 J / cm at a wavelength of 405 nm. ２ and a dumbbell-shaped test piece B1 is prepared by irradiating the composition with an irradiation amount such that the elongation at break of the test piece B1 is 40% to 1000% when the elongation at break of the test piece B1 is measured in accordance with JIS K 6251:2017.

9. The photocurable composition for stereolithography according to claim 8, wherein the tear strength is 100 N / mm to 300 N / mm, and the elongation at break is 40% to 800%.

10. A photocurable composition for stereolithography according to claim 1 or claim 9, which is used to manufacture an instrument for use in the oral cavity.

11. A three-dimensional object which is a cured product of the photocurable composition for stereolithography according to claim 1 or claim 9.

12. An appliance for use in the oral cavity, comprising the three-dimensional object according to claim 11.

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