Model material clear composition, model material composition set, and stereolithography composition set

Abstract

The present invention relates to a clear modeling material composition which is used in a material jetting stereolithography method and contains an ethylenically unsaturated compound (A) and a photopolymerization initiator, wherein: the ethylenically unsaturated compound (A) contains an ethylenically unsaturated monomer (A1) that has a dicyclopentenyl group and / or a dicyclopentanyl group, an ethylenically unsaturated compound (A2) that has an aliphatic cyclic structure in each molecule, while having a urethane group, and an ethylenically unsaturated monomer (A3) (excluding the ethylenically unsaturated monomer (A1)) that has an aliphatic cyclic structure in each molecule, while having no urethane group and no amide group; and the total mass of the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2) and the ethylenically unsaturated monomer (A3) based on the total mass of the ethylenically unsaturated compound (A) is 60% by mass or more.

Description

[Technical Field]

[0001] The present invention relates to a model material clear composition used for forming a model material by material jet stereolithography, a model material composition set comprising the model material clear composition and a model material color composition, and a material jet stereolithography composition set comprising the model material clear composition or the model material composition set. [Background technology]

[0002] Three-dimensional stereolithography, which produces a three-dimensional object by irradiating a photocurable resin composition with light such as ultraviolet light to continuously form cured layers having a predetermined shape, has been widely known. Among these, a material jet (inkjet) type stereolithography (hereinafter also referred to as "material jet stereolithography") has attracted widespread attention as a modeling method that enables the free production of three-dimensional objects using a 3D printer. This method involves ejecting a photocurable resin composition from a nozzle and then curing the resin composition by irradiating it with light such as ultraviolet light, thereby laminating cured layers having a predetermined shape to produce a three-dimensional object.

[0003] Photocurable resin compositions that can be used in material jet stereolithography have various requirements depending on their applications, one of which is a clear modeling material composition that is highly transparent (transparent) and has little yellow tinge, allowing for the production of three-dimensional objects. Various modeling material compositions have been proposed to meet such requirements. For example, Patent Document 1 describes a modeling material ink set that includes a clear ink that suppresses color change in the cured product by reducing the content of nitrogen-containing ethylenically unsaturated monomers contained as polymerizable compounds. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2018 / 164012 Summary of the Invention [Problem to be solved by the invention]

[0005] The clear ink described in Patent Document 1 has an improved effect of suppressing yellowing upon photocuring compared to previously proposed model material compositions, and can provide three-dimensionally shaped objects with less yellow tinge. However, in recent years, there has been a trend toward demands for higher appearance characteristics in three-dimensionally shaped objects obtained by material jet stereolithography, and clear model materials are being required to have even less yellow tinge and even greater transparency.

[0006] An object of the present invention is to provide a clear model material composition suitable for material jet stereolithography, which is resistant to color change upon photocuring and can produce a model material with excellent transparency and reduced yellowing. [Means for solving the problem]

[0007] As a result of intensive investigations aimed at solving the above-mentioned problems, the present inventors have found that cured products obtained from ethylenically unsaturated monomers (A1) having a dicyclopentenyl group and / or a dicyclopentanyl group tend to be less prone to yellowing due to light such as ultraviolet light irradiated during curing, and have thus completed the present invention. That is, the present invention provides the following preferred embodiments. [1] A clear model material composition for use in a material jet stereolithography method, comprising an ethylenically unsaturated compound (A) and a photopolymerization initiator, The ethylenically unsaturated compound (A) is Ethylenically unsaturated monomers (A1) having a dicyclopentenyl group and / or a dicyclopentanyl group; an ethylenically unsaturated compound (A2) having an aliphatic cyclic structure and a urethane group in the molecule; and An ethylenically unsaturated monomer (A3) having an aliphatic cyclic structure in the molecule and not having a urethane group or an amide group (excluding the above-mentioned ethylenically unsaturated monomer (A1)). Including, A model material clear composition, wherein the total mass of the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2) and the ethylenically unsaturated monomer (A3) is 60 mass% or more based on the total mass of the ethylenically unsaturated compound (A). [2] The model material clear composition according to [1], which contains 30 mass % or more of the ethylenically unsaturated monomer (A1) relative to the total mass of the ethylenically unsaturated compound (A). [3] The model material clear composition according to [1] or [2], wherein the ethylenically unsaturated monomer (A3) is an ethylenically unsaturated monomer that does not have a urethane group, an amide group, an aromatic group, or a vinyl ether group. [4] The model material clear composition according to any one of [1] to [3], wherein the ethylenically unsaturated monomer (A3) has at least one group selected from the group consisting of a cyclohexyl group, a 4-t-butylcyclohexyl group, a 3,5,5-trimethylcyclohexyl group, an isobornyl group, a tricyclodecanyl group, a dicyclopentadienyl group, and a 1,4-cyclohexanedimethanol group. [5] The model material clear composition according to any one of [1] to [4], which contains 10% by mass or more of the ethylenically unsaturated compound (A2) relative to the total mass of the ethylenically unsaturated compound (A). [6] The model material clear composition according to any one of [1] to [5], which contains an ethylenically unsaturated monomer having a nitrogen atom in the molecule and not having an aliphatic cyclic structure in an amount of 12 mass% or less relative to the total mass of the ethylenically unsaturated compound (A). [7] A model material composition set for use in material jet stereolithography, comprising the model material clear composition according to any one of [1] to [6] and a model material color composition containing an ethylenically unsaturated monomer (B). [8] The model material color composition contains 30% by mass or more and 85% by mass or less of a (meth)acrylate-based ethylenically unsaturated monomer (B1) and 10% by mass or more and 50% by mass or less of a nitrogen atom-containing ethylenically unsaturated monomer (B2) that is not a (meth)acrylate-based compound, based on the total mass of the model material color composition. [7] The model material composition set described in [7]. [9] The model material composition set according to [8], wherein the nitrogen atom-containing ethylenically unsaturated monomer (B2) that is not a (meth)acrylate compound is selected from the group consisting of (meth)acrylamides and N-vinyllactams.

[10] The model material color composition set according to any one of [7] to [9], wherein the model material color composition contains, as the ethylenically unsaturated monomer (B), a monofunctional ethylenically unsaturated monomer and a difunctional or higher ethylenically unsaturated monomer.

[11] The model material color composition set according to any one of [8] to

[10] , wherein the (meth)acrylate-based ethylenically unsaturated monomer (B1) is a (meth)acrylate-based ethylenically unsaturated monomer having an aliphatic cyclic structure and / or an aromatic cyclic structure.

[12] The model material composition set according to any one of [7] to

[11] , wherein the model material color composition comprises cyan, magenta, and yellow.

[13] The model material composition set according to

[12] , wherein the model material color composition further contains white and / or black.

[14] The model material composition set according to any one of [7] to

[13] , wherein both the model material clear composition and the model material color composition contain a surface conditioner.

[15] The model material composition set according to

[14] , wherein the content (mass%) of the surface conditioner contained in the model material clear composition relative to the total mass of the model material clear composition is greater than the content (mass%) of the surface conditioner contained in the model material color composition relative to the total mass of the model material color composition.

[16] A material jet stereolithography composition set comprising the model material clear composition according to any one of [1] to [6] or the model material composition set according to any one of [7] to

[15] , and a support material composition for forming a support material by material jet stereolithography. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a clear model material composition suitable for material jet stereolithography, which is unlikely to undergo color change upon photocuring and can produce a model material with excellent transparency and reduced yellowness. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail. Note that the scope of the present invention is not limited to the embodiments described here, and various modifications can be made without departing from the spirit of the present invention.

[0010] <Model material clear composition> The model material clear composition of the present invention contains an ethylenically unsaturated compound (A). The ethylenically unsaturated compound (A) is a polymerizable compound having at least one ethylenic double bond in the molecule, which has the property of being cured by energy rays. The ethylenically unsaturated compound (A) may be any of a polymerizable monomer, oligomer, and polymer. Furthermore, the ethylenically unsaturated compound may be a monofunctional ethylenically unsaturated compound having one ethylenic double bond in the molecule, or a polyfunctional ethylenically unsaturated compound having two or more ethylenic double bonds in the molecule.

[0011] The model material clear composition of the present invention contains an ethylenically unsaturated compound (A) that is an ethylenically unsaturated monomer (A1) having a dicyclopentenyl group and / or a dicyclopentanyl group (hereinafter simply referred to as "ethylenically unsaturated monomer (A1)"). For reasons that are unclear, cured products obtained from the ethylenically unsaturated monomer (A1) having a dicyclopentenyl group and / or a dicyclopentanyl group tend to be less prone to yellowing when exposed to light such as ultraviolet light during curing. Therefore, by including the ethylenically unsaturated monomer (A1) as a polymerizable compound in the model material composition, color changes (particularly yellowing) are less likely to occur when the model material composition is cured by light irradiation, and a model material (stereolithography product) with excellent transparency and reduced yellowness can be obtained.

[0012] The ethylenically unsaturated monomer (A1) is not particularly limited as long as it is a polymerizable monomer having at least one group selected from a dicyclopentenyl group and a dicyclopentanyl group and having at least one ethylenic double bond in the molecule, and may be a monofunctional monomer or a polyfunctional monomer. Examples of the ethylenically unsaturated monomer (A1) include (meth)acrylates having a dicyclopentenyl group and / or a dicyclopentanyl group. Specific examples include dicyclopentenyl acrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl acrylate, dicyclopentanyl methacrylate, ethoxylated dicyclopentenyl acrylate, ethoxylated dicyclopentenyl methacrylate, alkoxylated dicyclopentenyl acrylate, alkoxylated dicyclopentenyl methacrylate, dicyclopentanyloxyethyl acrylate, dicyclopentanyloxyethyl methacrylate, ethoxylated dicyclopentanyl acrylate, ethoxylated dicyclopentanyl methacrylate, alkoxylated dicyclopentanyl acrylate, and alkoxylated dicyclopentanyl methacrylate. Among these, (meth)acrylates having a dicyclopentenyl group and / or a dicyclopentanyl group are preferred, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, dicyclopentanyl acrylate, and dicyclopentanyloxyethyl acrylate are more preferred, dicyclopentenyloxyethyl acrylate, dicyclopentenyloxyethyl methacrylate, and dicyclopentanyloxyethyl acrylate are even more preferred, and dicyclopentenyloxyethyl acrylate is particularly preferred. These ethylenically unsaturated monomers (A1) may be used alone or in combination of two or more. In this specification, "(meth)acrylate" refers to either or both of acrylate and methacrylate, and the same applies to "(meth)acrylamide" and the like hereinafter.

[0013] The content of the ethylenically unsaturated monomer (A1) in the model material clear composition of the present invention is preferably 30% by mass or more, more preferably 35% by mass or more, even more preferably 40% by mass or more, particularly preferably 41% by mass or more, and particularly preferably 45% by mass or more, based on the total mass of the ethylenically unsaturated compounds (A). When the content of the ethylenically unsaturated monomer (A1) relative to the total mass of the ethylenically unsaturated compounds (A) is equal to or greater than the above-mentioned lower limit, the model material clear composition exhibits excellent yellowing suppression effect upon photocuring, and the resulting model material exhibits little yellowness and high transparency. Therefore, from the viewpoint of improving the transparency of the resulting model material, a higher content of the ethylenically unsaturated monomer (A1) is preferable. On the other hand, for example, by adjusting the content in relation to the ethylenically unsaturated compound (A2) and the ethylenically unsaturated monomer (A3), etc., described below, the resulting model material exhibits reduced yellowness, ensuring high transparency, and easily controlling mechanical properties such as strength and hardness. Therefore, the content of the ethylenically unsaturated monomer (A1) is preferably 85% by mass or less, more preferably 80% by mass or less, even more preferably 75% by mass or less, particularly preferably 70% by mass or less, especially preferably 69% by mass or less, and even more particularly preferably 65% ​​by mass or less, based on the total mass of the ethylenically unsaturated compound (A).

[0014] The model material clear composition of the present invention contains, as the ethylenically unsaturated compound (A), an ethylenically unsaturated compound (A2) (hereinafter simply referred to as "ethylenically unsaturated compound (A2)") having an alicyclic structure and a urethane group in the molecule. By containing the ethylenically unsaturated compound (A2), the model material clear composition can easily impart the desired strength and hardness to the resulting model material.

[0015] The ethylenically unsaturated compound (A2) is not particularly limited as long as it is a polymerizable compound having an alicyclic structure in the molecule and having at least one urethane group and at least one ethylenic double bond, and may be any of a monomer, an oligomer, and a polymer. In this specification, the alicyclic structure means a structure in which carbon atoms are bonded in a ring and includes a saturated or unsaturated carbon ring that does not have aromaticity, and examples thereof include a cycloalkane skeleton, a cycloalkene skeleton, an adamantane skeleton, a norbornane skeleton, an isophorone skeleton, and a tricyclodecane skeleton.

[0016] Examples of the ethylenically unsaturated compound (A2) include the urethane (meth)acrylates having an aliphatic cyclic structure and urethane (meth)acrylate oligomers having an aliphatic cyclic structure, as exemplified above. Specific examples include urethane (meth)acrylate oligomers having a dicyclohexylmethane structure, urethane (meth)acrylate oligomers having an isophorone structure, and urethane (meth)acrylate oligomers having a cyclohexylmethane structure. Among these, urethane (meth)acrylate oligomers having an aliphatic cyclic structure are preferred, (meth)acrylate oligomers having a dicyclohexylmethane structure and urethane (meth)acrylate oligomers having an isophorone structure are more preferred, (meth)acrylate oligomers having a dicyclohexylmethane structure are even more preferred, and acrylate oligomers having a dicyclohexylmethane structure are particularly preferred. The use of an oligomer as the ethylenically unsaturated compound (A2) makes it easier to obtain a model material that has a good balance of strength and moderate toughness. These ethylenically unsaturated compounds (A2) may be used alone or in combination of two or more. In this specification, the term "oligomer" refers to a polymer having a weight average molecular weight (M w The preferred weight average molecular weight (M) of the oligomer is 500 to 10,000. w ) is 800 or more, and more preferably exceeds 1,000. w) means the weight average molecular weight in terms of polystyrene measured by GPC (gel permeation chromatography).

[0017] The content of the ethylenically unsaturated compound (A2) in the model material clear composition of the present invention is preferably 10% by mass or more, more preferably 11% by mass or more, even more preferably 15% by mass or more, particularly preferably 18% by mass or more, and particularly preferably 20% by mass or more, based on the total mass of the ethylenically unsaturated compounds (A). When the content of the ethylenically unsaturated compound (A2) relative to the total mass of the ethylenically unsaturated compounds (A) is equal to or greater than the above-mentioned lower limit, the strength and hardness of the resulting model material are likely to be improved. On the other hand, for example, in order to fully exhibit the effect of suppressing discoloration (yellowing) and improving transparency of the model material by using the ethylenically unsaturated monomer (A1) as a polymerizable compound, the content of the ethylenically unsaturated compound (A2) is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, particularly preferably 35% by mass or less, particularly preferably 29% by mass or less, and even more particularly preferably 25% by mass or less, based on the total mass of the ethylenically unsaturated compounds (A).

[0018] In the model material clear composition of the present invention, the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated compound (A2) [ethylenically unsaturated monomer (A1) / ethylenically unsaturated compound (A2)] can be appropriately determined depending on the type of polymerizable compound used, the desired mechanical properties of the model material, etc. The mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated compound (A2) is, for example, preferably 1.1 or more, more preferably 1.5 or more, even more preferably 2 or more, and preferably 10 or less, more preferably 8 or less, even more preferably 7 or less, and particularly preferably 5 or less. When the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated compound (A2) is within the above range, the resulting model material has little yellowness, and is easily imparted with well-balanced mechanical properties while ensuring high transparency. In addition, when the model material clear composition contains multiple types of ethylenically unsaturated monomers (A1) and / or ethylenically unsaturated compounds (A2), it is preferable that the mass ratio of each of the polymerizable compounds in the total mass is within the above range.

[0019] The model material clear composition of the present invention contains, as the ethylenically unsaturated compound (A), an ethylenically unsaturated monomer (A3) (hereinafter simply referred to as "ethylenically unsaturated monomer (A3)") that has an alicyclic structure in its molecule and does not contain a urethane group or an amide group. The ethylenically unsaturated monomer (A3) does not include the ethylenically unsaturated monomer (A1). Like the ethylenically unsaturated compound (A2), the ethylenically unsaturated monomer (A3) can be a component that increases the glass transition temperature of the model material clear composition, thereby easily imparting the desired strength and hardness to the resulting model material. By using the ethylenically unsaturated compound (A2) in combination with the ethylenically unsaturated monomer (A3), the effect of suppressing discoloration (yellowing) and improving transparency of the model material, achieved by using the ethylenically unsaturated monomer (A1), is sufficiently ensured, while the resulting model material is easily imparted with high strength, hardness, and appropriate toughness. This makes it possible to obtain a model material that is less yellowish, highly transparent, has excellent appearance characteristics, and has well-balanced mechanical properties.

[0020] The ethylenically unsaturated monomer (A3) is not particularly limited as long as it is a polymerizable compound having an alicyclic structure in the molecule, not containing a urethane group or an amide group, and having at least one ethylenic double bond, and may be a monofunctional or polyfunctional monomer. Examples of the alicyclic structure of the ethylenically unsaturated monomer (A3) include structures similar to the alicyclic structure of the ethylenically unsaturated compound (A2). Examples of the ethylenically unsaturated monomer (A3) include monofunctional (meth)acrylates having an alicyclic structure other than a cyclopentenyl group or a cyclopentanyl group and not containing a urethane group or an amide group, and bifunctional or higher functional (meth)acrylates having an alicyclic structure other than a cyclopentenyl group or a cyclopentanyl group and not containing a urethane group or an amide group.

[0021] In the present invention, the ethylenically unsaturated monomer (A3) is preferably an ethylenically unsaturated monomer that does not have a urethane group, an amide group, an aromatic group, or a vinyl ether group. Furthermore, the ethylenically unsaturated monomer (A3) preferably has at least one group selected from the group consisting of a cyclohexyl group, a 4-t-butylcyclohexyl group, a 3,5,5-trimethylcyclohexyl group, an isobornyl group, a tricyclodecanyl group, a dicyclopentadienyl group, and a 1,4-cyclohexanedimethanol group. It is more preferred that the ethylenically unsaturated monomer (A3) does not contain a urethane group, an amide group, an aromatic group, or a vinyl ether group, and has at least one group selected from the group consisting of a cyclohexyl group, a 4-t-butylcyclohexyl group, a 3,5,5-trimethylcyclohexyl group, an isobornyl group, a tricyclodecanyl group, a dicyclopentadienyl group, and a 1,4-cyclohexanedimethanol group. When the ethylenically unsaturated monomer (A3) has the above structure, the glass transition temperature of the model material clear composition tends to increase, and the desired strength and hardness can be easily imparted to the obtained model material.

[0022] Specific examples of the ethylenically unsaturated monomer (A3) include cyclohexyl acrylate, 4-t-butylcyclohexyl acrylate, 3,5,5-trimethylcyclohexyl acrylate, isobornyl acrylate, tricyclodecane dimethanol diacrylate, dicyclopentadienyl methacrylate, and 1,4-cyclohexane dimethanol monoacrylate. Among these, one selected from the group consisting of cyclohexyl acrylate, 4-t-butylcyclohexyl acrylate, 3,5,5-trimethylcyclohexyl acrylate, isobornyl acrylate, tricyclodecane dimethanol diacrylate, and 1,4-cyclohexane dimethanol monoacrylate is preferred, with 3,5,5-trimethylcyclohexyl acrylate and / or isobornyl acrylate being more preferred. These ethylenically unsaturated monomers (A3) may be used alone or in combination of two or more.

[0023] The content of the ethylenically unsaturated monomer (A3) in the model material clear composition of the present invention is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more, and particularly preferably 21% by mass or more, relative to the total mass of the ethylenically unsaturated compounds (A). When the content of the ethylenically unsaturated monomer (A3) relative to the total mass of the ethylenically unsaturated compounds (A) is equal to or greater than the above-mentioned lower limit, the strength and hardness of the resulting model material are likely to be improved. On the other hand, for example, in order to fully exhibit the effects of suppressing discoloration (yellowing) and improving transparency of the model material, which are achieved by using the ethylenically unsaturated monomer (A1) as a polymerizable compound, the content of the ethylenically unsaturated monomer (A3) is preferably 50% by mass or less, more preferably 45% by mass or less, even more preferably 40% by mass or less, particularly preferably 35% by mass or less, and particularly preferably less than 30% by mass, relative to the total mass of the ethylenically unsaturated compounds (A).

[0024] In the model material clear composition of the present invention, the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated monomer (A3) [ethylenically unsaturated monomer (A1) / ethylenically unsaturated monomer (A3)] can be appropriately determined depending on the type of polymerizable compound used, the desired mechanical properties of the model material, etc. The mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated monomer (A3) is preferably 1.5 or more, more preferably 1.8 or more, even more preferably more than 2, and is preferably 10 or less, more preferably 8 or less, even more preferably 7 or less, and particularly preferably 5 or less. When the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated monomer (A3) is within the above range, the resulting model material is less likely to have yellowish tinge, is highly transparent, and has well-balanced mechanical properties. In addition, when the model material clear composition contains multiple types of ethylenically unsaturated monomers (A1) and / or ethylenically unsaturated monomers (A3), it is preferable that the mass ratio of each of the polymerizable compounds in the total mass is within the above range.

[0025] In the model material clear composition of the present invention, the mass ratio of the ethylenically unsaturated compound (A2) to the ethylenically unsaturated monomer (A3) [ethylenically unsaturated compound (A2) / ethylenically unsaturated monomer (A3)] can be appropriately determined depending on the type of polymerizable compound used, the desired mechanical properties of the model material, etc. The mass ratio of the ethylenically unsaturated compound (A2) to the ethylenically unsaturated monomer (A3) is preferably 0.5 or more, more preferably 0.8 or more, and is preferably 2.5 or less, more preferably 2 or less, and even more preferably 1.4 or less. When the mass ratio of the ethylenically unsaturated compound (A2) to the ethylenically unsaturated monomer (A3) is within the above range, the resulting model material is likely to be imparted with high strength, hardness, and appropriate toughness. In addition, when the model material clear composition contains multiple types of ethylenically unsaturated compounds (A2) and / or ethylenically unsaturated monomers (A3), it is preferable that the mass ratio of each polymerizable compound to the total mass of the polymerizable compounds is within the above range.

[0026] In the model material clear composition of the present invention, the ratio of the total mass of the ethylenically unsaturated monomer (A1) to the total mass of the ethylenically unsaturated compound (A2) and the ethylenically unsaturated monomer (A3) [ethylenically unsaturated monomer (A1) / ethylenically unsaturated compound (A2)+ethylenically unsaturated monomer (A3)] can be appropriately determined depending on the type of polymerizable compound used, the desired mechanical properties of the model material, etc. This mass ratio is preferably 0.5 or more, more preferably 0.9 or more, even more preferably 1 or more, particularly preferably more than 1, and preferably 4 or less, more preferably 3 or less, and even more preferably 2 or less. When the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated compound (A2) and the ethylenically unsaturated monomer (A3) is within the above range, the resulting model material can be easily imparted with well-balanced mechanical properties while maintaining high transparency and little yellowing.

[0027] In the model material clear composition of the present invention, the total mass of the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2), and the ethylenically unsaturated monomer (A3) is preferably 60% by mass or more based on the total mass of the ethylenically unsaturated compound (A). When the total mass of the three polymerizable compounds, each having an alicyclic structure in its molecule, is equal to or greater than the above-mentioned lower limit, the resulting model material is less yellowish and has high transparency, while also being able to exhibit well-balanced mechanical properties. The total mass of the three polymerizable compounds is more preferably 65% ​​by mass or more, even more preferably 70% by mass or more, and particularly preferably 75% by mass or more, based on the total mass of the ethylenically unsaturated compound (A). The upper limit of the total mass of the three polymerizable compounds is not particularly limited; the ethylenically unsaturated compound (A) may consist solely of the three polymerizable compounds (i.e., 100% by mass), or may be, for example, 95% by mass or less, or 90% by mass or less.

[0028] The model material clear composition of the present invention may contain, as the ethylenically unsaturated compound (A), an ethylenically unsaturated compound (A4) other than the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2), and the ethylenically unsaturated monomer (A3) (hereinafter simply referred to as the "ethylenically unsaturated compound (A4)"). The ethylenically unsaturated compound (A4) is not particularly limited as long as it is a polymerizable compound having at least one ethylenic double bond in the molecule, and is different from the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2), and the ethylenically unsaturated monomer (A3). The ethylenically unsaturated compound (A4) may be a monomer, oligomer, or polymer. Furthermore, it may be monofunctional or polyfunctional.

[0029] Examples of the ethylenically unsaturated compound (A4) include ethylenically unsaturated compounds that do not have an aliphatic cyclic structure within the molecule, such as alkyl (meth)acrylates with linear or branched alkyl groups, (meth)acrylates with aromatic or heterocyclic structures within the molecule, and nitrogen-containing monofunctional ethylenically unsaturated monomers such as (meth)acrylamides and N-vinyl lactams. Specific examples include alkyl (meth)acrylates, (meth)acrylates with aromatic or heterocyclic structures within the molecule, and compounds exemplified as nitrogen-containing ethylenically unsaturated monomers (B2), all of which are exemplified as (meth)acrylate-based ethylenically unsaturated monomers (B1) that may be contained in the model material color composition described below. These ethylenically unsaturated compounds (A4) may be used alone or in combination of two or more. In this specification, an aromatic cyclic structure refers to an aromatic cyclic structure in which carbon atoms are bonded in a ring, and a heterocyclic structure refers to a structure in which carbon atoms and one or more heteroatoms are bonded in a ring.

[0030] In one embodiment of the present invention, when the ethylenically unsaturated compound (A) contains the ethylenically unsaturated compound (A4), the content of the ethylenically unsaturated compound (A4) is preferably 38% by mass or less, more preferably 20% by mass or less, even more preferably 15% by mass or less, and particularly preferably 12% by mass or less, based on the total mass of the ethylenically unsaturated compounds (A). When the content of the ethylenically unsaturated compound (A4) is equal to or less than the above-mentioned upper limit, the resulting model material is likely to have well-balanced mechanical properties while maintaining high transparency and little yellowing. Furthermore, the lower limit of the content of the ethylenically unsaturated compound (A4) is not particularly limited. In another embodiment of the present invention, the model material clear composition may be substantially free of the ethylenically unsaturated compound (A4). The content of the ethylenically unsaturated compound (A4) may be, for example, 1% by mass or more, 3% by mass or more, or 5% by mass or more, based on the total mass of the ethylenically unsaturated compounds (A).

[0031] In one embodiment of the present invention, when the ethylenically unsaturated compound (A) contains an ethylenically unsaturated compound (A4), the ethylenically unsaturated compound (A4) is preferably an ethylenically unsaturated monomer (A4') having a nitrogen atom in the molecule and not having an aliphatic cyclic structure (hereinafter simply referred to as "ethylenically unsaturated monomer (A4')"). By containing the ethylenically unsaturated monomer (A4'), the hardness of the obtained model material is likely to be improved. Examples of the ethylenically unsaturated monomer (A4') include compounds exemplified as the nitrogen-containing ethylenically unsaturated monomer (B2) that can be contained in the model material color composition described below. Examples include (meth)acrylamides (e.g., N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, hydroxyethylacrylamide, hydroxypropylacrylamide, acryloylmorpholine, etc.), N-vinyllactams (e.g., N-vinylpyrrolidone, N-vinylcaprolactam, etc.), and N-vinylformamide. These may be used alone or in combination of two or more. Among these, acryloylmorpholine is preferred because it has a high glass transition temperature and high curability, thereby imparting high hardness to the resulting model material. In addition, acryloylmorpholine also functions well as a diluent, so that the viscosity of the model material clear composition can be maintained within an appropriate range while allowing a larger amount of oligomer components, such as the ethylenically unsaturated compound (A2), which are useful for improving the brittleness resistance of the resulting model material, to be incorporated into the model material clear composition. Therefore, by including acryloylmorpholine, a model material can be obtained that has a good balance of high hardness and appropriate toughness.

[0032] In one embodiment of the present invention, when the ethylenically unsaturated compound (A) contains the ethylenically unsaturated monomer (A4'), the content of the ethylenically unsaturated monomer (A4') is preferably 12% by mass or less, more preferably 11% by mass or less, and even more preferably 10.5% by mass or less, based on the total mass of the ethylenically unsaturated compound (A). When the content of the ethylenically unsaturated monomer (A4') is below the above-mentioned upper limit, the strength-improving effect of the ethylenically unsaturated monomer (A4') is easily obtained while maintaining high transparency with little yellowing in the resulting model material. The ethylenically unsaturated monomer (A4') generally tends to yellow more easily upon light irradiation than nitrogen-free polymerizable compounds. The model material clear composition of the present invention uses the ethylenically unsaturated monomer (A1) as a polymerizable compound, thereby providing excellent effects in suppressing discoloration (yellowing) and improving transparency of the resulting model material, and can therefore contain a relatively large amount of the ethylenically unsaturated monomer (A4'), which is prone to yellowing. Therefore, the lower limit of the content of the ethylenically unsaturated monomer (A4') is not particularly limited, and may be, for example, 1 mass% or more, 3 mass% or more, or 5 mass% or more based on the total mass of the ethylenically unsaturated compound (A).

[0033] In another aspect of the present invention, the content of the ethylenically unsaturated monomer (A4') in the model material clear composition may be, for example, 5 mass% or less, 3 mass% or less, or 1 mass% or less, based on the total mass of the ethylenically unsaturated compound (A), and the model material clear composition may not contain the ethylenically unsaturated monomer (A4').

[0034] The model material clear composition of the present invention may contain a polymerizable compound other than the ethylenically unsaturated compound (A) as a polymerizable compound. Examples of such other polymerizable compounds include oxygen-containing cyclic compounds such as oxirane compounds and oxetane compounds, and nitrogen-containing cyclic compounds such as aziridine compounds and acetidine compounds. When the model material clear composition of the present invention contains a polymerizable compound other than the ethylenically unsaturated compound (A), the content of such a polymerizable compound is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 5% by mass or less, based on the total mass of the ethylenically unsaturated compound (A).

[0035] The content of the ethylenically unsaturated compound (A) in the model material clear composition of the present invention is preferably 80% by mass or more, more preferably 85% by mass or more, and even more preferably 90% by mass or more, based on the total mass of the model material clear composition. When the content of the ethylenically unsaturated compound (A) in the model material clear composition is equal to or greater than the above-mentioned lower limit, a model material clear composition is obtained that is likely to impart high transparency with reduced yellowness and well-balanced mechanical properties to the resulting model material. The upper limit of the content of the ethylenically unsaturated compound (A) is not particularly limited, but is usually 99% by mass or less, preferably 98% by mass or less, based on the total mass of the model material clear composition.

[0036] The content of the polymerizable compound in the model material clear composition of the present invention is preferably 90% by mass or more, more preferably 95% by mass or more, based on the total mass of the model material clear composition, and is preferably 99.9% by mass or less, more preferably 99.5% by mass or less.

[0037] The model material clear composition of the present invention contains a photopolymerization initiator. The photopolymerization initiator is not particularly limited as long as it is a compound that promotes a radical reaction when irradiated with light having a wavelength in the ultraviolet, near-ultraviolet, or visible light range. Examples of the photopolymerization initiator include benzoin compounds (e.g., benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, benzoin isobutyl ether, etc.), acetophenone compounds (e.g., acetophenone, 2,2-diethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 2-hydroxy-2-methyl-phenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, etc.), anthraquinone compounds (e.g., 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-chloroanthraquinone, 2-amylanthraquinone, etc.), and the like. thioxanthone compounds (e.g., 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, etc.), ketal compounds (e.g., acetophenone dimethyl ketal, benzyl dimethyl ketal, etc.), benzophenone compounds (e.g., benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, 4,4'-bismethylaminobenzophenone, etc.), acylphosphine oxide compounds (e.g., 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), and mixtures of these compounds. These may be used alone or in combination of two or more.Among these, at least one compound selected from the group consisting of acetophenone compounds and acylphosphine oxide compounds is preferred, as the model material obtained by photocuring the model material ink is less likely to yellow and the resulting model material has high light resistance and is less likely to yellow over time. At least one compound selected from the group consisting of 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, and 2,4,6-trimethylbenzoyl-diphenylphosphine oxide is more preferred. Commercially available photopolymerization initiators may also be used, such as BASF's IRGACURE TPO.

[0038] The content of the photopolymerization initiator in the model material clear composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, based on the total mass of the model material clear composition, and is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 8% by mass or less. When the content of the photopolymerization initiator is within the above range, unreacted polymerization components can be reduced, sufficiently enhancing the curability of the model material, and yellowing of the model material over time caused by remaining unreacted photopolymerization initiator can be suppressed.

[0039] The model material clear composition may contain other additives as needed, as long as they do not impair the effects of the present invention. Examples of other additives include storage stabilizers, surface conditioners, antioxidants, UV absorbers, light stabilizers, polymerization inhibitors, chain transfer agents, fillers, diluents, thickeners, etc.

[0040] The surface conditioner is a component that adjusts the surface tension of the modeling material clear composition within an appropriate range, and its type is not particularly limited. By adjusting the surface tension of the modeling material clear composition within an appropriate range, it is possible to stabilize the discharge properties and suppress interfacial mixing between the modeling material clear composition and the modeling material color composition and / or support material composition. As a result, a modeling material with good dimensional accuracy can be obtained.

[0041] Examples of the surface conditioner include silicone compounds. Examples of the silicone compounds include silicone compounds having a polydimethylsiloxane structure. Specific examples include polyether-modified polydimethylsiloxane, polyester-modified polydimethylsiloxane, and polyaralkyl-modified polydimethylsiloxane. These include the trade names BYK-300, BYK-302, BYK-306, BYK-307, BYK-310, BYK-315, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-337, BYK-344, BYK-370, BYK-375, BYK-377, BYK-UV3500, BYK-UV3510, BYK-UV3570 (all manufactured by BYK-Chemie), and TEGO-Rad210. 0, TEGO-Rad2200N, TEGO-Rad2250, TEGO-Rad2300, TEGO-Rad2500, TEGO-Rad2600, TEGO-Rad2700 (all manufactured by Degussa), Granol 100, Granol 115, Granol 400, Granol 410, Granol 435, Granol 440, Granol 450, B-1484, Polyflow ATF-2, KL-600, UCR-L72, UCR-L93 (manufactured by Kyoeisha Chemical Co., Ltd.), etc. may also be used. Surface conditioners other than silicone-based compounds (e.g., fluorine-based surface conditioners, etc.) may also be used. These may be used alone or in combination of two or more.

[0042] When the model material clear composition contains a surface conditioner, the content thereof is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.05% by mass or more, based on the total mass of the model material clear composition, and is preferably 3% by mass or less, more preferably 2% by mass or less, and even more preferably 1.5% by mass or less. When the content of the surface conditioner is within the above range, it is easy to adjust the surface tension of the model material clear composition to an appropriate range.

[0043] When the model material clear composition of the present invention is used together with the model material color composition described below, it is preferable that the amount of surface conditioner contained in the model material clear composition (the content (mass %) of the surface conditioner relative to the total mass of the model material clear composition) is greater than the amount of surface conditioner contained in the model material color composition (the content (mass %) of the surface conditioner relative to the total mass of the model material color composition). If the amount of surface conditioner contained in the model material clear composition is greater than the amount of surface conditioner contained in the model material color composition, repulsion between the model material clear composition and the model material color composition at their interface is suppressed. This results in a clearer boundary between the clear model material and the color model material in the resulting model material, allowing for the production of a model material with excellent appearance. In this case, the amount of surface conditioner contained in the model material clear composition can be determined appropriately depending on the types and ratios of the polymerizable compounds constituting the model material clear composition and the color composition. In one embodiment of the present invention, the amount (mass %) of the surface conditioner contained in the model material clear composition is preferably 1.2 times or more, more preferably 1.5 times or more, and even more preferably 1.8 times or more, relative to the amount (mass %) of the surface conditioner contained in the model material color composition, and is preferably 3 times or less, more preferably 2.8 times or less, and even more preferably 2.5 times or less.

[0044] The storage stabilizer is a component that can improve the storage stability of the model material clear composition. It can also prevent head clogging caused by the polymerization of polymerizable compounds due to thermal energy. Examples of storage stabilizers include hindered amine compounds (HALS), phenolic antioxidants, and phosphorus-based antioxidants. Specific examples include hydroquinone, methoquinone, benzoquinone, p-methoxyphenol, hydroquinone monomethyl ether, hydroquinone monobutyl ether, TEMPO, 4-hydroxy-TEMPO, TEMPOL, Al cupferron, Irgastab UV-10, Irgastab UV-22, Firstcure ST-1 (manufactured by Albemarle), t-butylcatechol, pyrogallol, and BASF's TINUVIN 111 FDL, TINUVIN 144, TINUVIN 292, TINUVIN XP40, TINUVIN XP60, and TINUVIN 400. These may be used alone or in combination.

[0045] When the model material clear composition contains a storage stabilizer, the content thereof is preferably 0.01 to 5% by mass based on the total mass of the model material clear composition, from the viewpoint of easily achieving the above-mentioned effects.

[0046] The model material clear composition of the present invention typically does not contain a colorant or contains only a small amount of a pigment and / or dye such as a bluing agent. Therefore, the content of the colorant in the model material clear composition of the present invention is typically 0.1% by mass or less, more preferably 0.05% by mass or less, based on the total mass of the model material clear composition, with the lower limit being 0% by mass or more.

[0047] The model material clear composition of the present invention is used in material jet stereolithography, and therefore preferably has a viscosity of 1 mPa·s or more and less than 500 mPa·s at 25°C. From the viewpoint of improving dischargeability from the material jet nozzle, the viscosity at 25°C is preferably 10 to 400 mPa·s, and more preferably 20 to 300 mPa·s. The viscosity can be measured in accordance with JIS Z 8803 using an R100 viscometer. The viscosity of the model material clear composition can be controlled by adjusting the type and blending ratio of the polymerizable compound, the type and amount of dilution solvent and thickener, etc.

[0048] The surface tension of the model material clear composition of the present invention is preferably 24 to 34 mN / m, more preferably 28 to 30 mN / m. When the surface tension is within this range, droplets can be normally formed from the nozzle even when the material jet is discharged at high speed, making it easier to ensure an appropriate droplet volume and improve modeling accuracy. In the present invention, the surface tension of the model material clear composition can be controlled by adjusting the type and amount of the surface conditioner, etc.

[0049] The method for producing the model material clear composition of the present invention is not particularly limited, and it can be produced, for example, by uniformly mixing the components that make up the model material clear composition using a mixer or stirrer.

[0050] <Model material composition set> The model material clear composition of the present invention is suitable for producing colorless and highly transparent model materials, and when combined with a model material color composition, it can provide model materials with a variety of appearances and surface textures. Therefore, the present invention also covers a model material composition set containing the model material clear composition of the present invention and the model material color composition.

[0051] The model material clear composition of the present invention can be used in combination with various conventionally known model material color compositions. A model material color composition that can be suitably used together with the model material clear composition of the present invention includes a model material color composition containing an ethylenically unsaturated monomer (B), preferably a model material color composition containing 30% by mass or more and 85% by mass or less of a (meth)acrylate-based ethylenically unsaturated monomer (B1) and 10% by mass or more and 50% by mass or less of a nitrogen-containing ethylenically unsaturated monomer (B2) that is not a (meth)acrylate-based compound, based on the total mass of the model material color composition.

[0052] The model material color composition included in the model material composition set of the present invention contains an ethylenically unsaturated monomer (B). The ethylenically unsaturated monomer (B) is a polymerizable monomer having at least one ethylenic double bond in the molecule, which has the property of being cured by energy rays. The ethylenically unsaturated monomer (B) may be a monofunctional ethylenically unsaturated monomer having one ethylenic double bond in the molecule, or a polyfunctional ethylenically unsaturated monomer having two or more ethylenic double bonds in the molecule. Examples of the ethylenically unsaturated monomer (B) include (meth)acrylates, (meth)acrylamides, N-vinyl lactams, vinyl ethers, and maleimides.

[0053] The model material color composition included in the model material composition set of the present invention preferably contains a (meth)acrylate-based ethylenically unsaturated monomer (B1) (hereinafter simply referred to as "ethylenically unsaturated monomer (B1)") as the ethylenically unsaturated monomer (B). The ethylenically unsaturated monomer (B1) may be a monofunctional (meth)acrylate (monofunctional ethylenically unsaturated monomer) or a polyfunctional (meth)acrylate (polyfunctional ethylenically unsaturated monomer). Examples of the (meth)acrylate include alkyl (meth)acrylates having a linear or branched alkyl group, (meth)acrylates having an aliphatic cyclic structure and / or an aromatic cyclic structure in the molecule, (meth)acrylates having a heterocyclic structure, (meth)acrylates having a linear or branched alkylene group, and alkylene glycol (meth)acrylates having a linear or branched alkylene glycol group. These may be used alone or in combination of two or more.

[0054] The linear or branched alkyl group in the alkyl(meth)acrylate is preferably an alkyl group having 4 to 30 carbon atoms, more preferably 6 to 25 carbon atoms, and specific examples thereof include an octyl group, an isooctyl group, a 2-ethylhexyl group, a nonyl group, an isononyl group, a lauryl group, a stearyl group, an isostearyl group, a t-butyl group, etc. The alkyl(meth)acrylate is usually a monofunctional (meth)acrylate.

[0055] The (meth)acrylate having an aliphatic cyclic structure and / or an aromatic cyclic structure has an alicyclic group and / or an aromatic hydrocarbon group in the molecule, and these groups include alicyclic groups and aromatic hydrocarbon groups preferably having 6 to 20 carbon atoms, more preferably 8 to 14 carbon atoms. Examples of the alicyclic group include a cyclohexyl group, a 4-t-butylcyclohexyl group, an isobornyl group, a dicyclopentanyl group, a tricyclodecyl group, and an adamantyl group. Examples of the aromatic hydrocarbon group include a phenoxyethyl group, an ethoxylated phenyl group (e.g., 2-(2-ethoxyethoxy)phenyl), a phenylphenol group, and a fluorene group. The (meth)acrylate having an aliphatic cyclic structure and / or an aromatic cyclic structure may be either monofunctional or polyfunctional, but is preferably a monofunctional (meth)acrylate.

[0056] The (meth)acrylate having a heterocyclic structure has a heterocyclic group in the molecule, and the heterocyclic group preferably has 5 to 20 carbon atoms, more preferably 5 to 14 carbon atoms. Examples of the (meth)acrylate having a heterocyclic structure include tetrahydrofurfuryl (meth)acrylate, 4-(meth)acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, and 4-(meth)acryloyloxymethyl-2-cyclohexyl-1,3-dioxolane. The (meth)acrylate having a heterocyclic structure may be either monofunctional or polyfunctional, but is preferably a monofunctional (meth)acrylate.

[0057] The alkylene group in the (meth)acrylate having a linear or branched alkylene group preferably has 2 to 30 carbon atoms, more preferably 3 to 20 carbon atoms. Examples of such alkylene groups include pentaerythritol, dipentaerythritol, and dimethyloltricyclodecane. Specific examples of the (meth)acrylate having a linear or branched alkylene group include pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and dimethyloltricyclodecane di(meth)acrylate. The (meth)acrylate having a linear or branched alkylene group is usually a polyfunctional (meth)acrylate, preferably a polyfunctional (meth)acrylate having 2 to 10, and more preferably 2 to 6 (meth)acrylate groups.

[0058] The alkylene glycol group in the (meth)acrylate having a linear or branched alkylene glycol group is preferably an alkylene glycol group having 4 to 25 carbon atoms, more preferably 6 to 20 carbon atoms. Examples of the alkylene glycol group include (n) ethylene glycol groups such as tripropylene glycol group, 1,6-hexanediol group, neopentyl glycol group, 1,9-nonanediol group, 3-methyl-1,5-pentanediol group, 2-n-butyl-2-ethyl-1,3-propanediol group, pentaerythritol group, diethylene glycol group, and triethylene glycol group, and (n) propylene glycol groups such as dipropylene glycol group and tripropylene glycol group. Specific examples of the (meth)acrylate having a linear or branched alkylene glycol group include di(meth)acrylates of the above alkylene glycols and tri(meth)acrylates of the above alkylene glycols. The (meth)acrylate having a linear or branched alkylene glycol group may be either monofunctional or polyfunctional, but is preferably a polyfunctional (meth)acrylate, more preferably a polyfunctional (meth)acrylate having 1 to 6, and even more preferably 2 or 3 (meth)acrylate groups.

[0059] From the viewpoint of reducing the viscosity of the composition and facilitating improved ejection properties in the material jet, and from the viewpoint of facilitating improved strength and hardness of the resulting model material, the model material color composition preferably contains, as the ethylenically unsaturated monomer (B1), a (meth)acrylate-based ethylenically unsaturated monomer having an aliphatic cyclic structure and / or an aromatic cyclic structure, more preferably a (meth)acrylate-based ethylenically unsaturated monomer having an aliphatic cyclic structure, and even more preferably isobornyl (meth)acrylate and / or cyclohexyl (meth)acrylate.

[0060] The content of the ethylenically unsaturated monomer (B1) in the model material color composition is preferably 30% by mass or more, more preferably 35% by mass or more, even more preferably 40% by mass or more, particularly preferably 45% by mass or more, based on the total mass of the model material color composition, and is preferably 85% by mass or less, more preferably 75% by mass or less, even more preferably 70% by mass or less, particularly preferably 65% ​​by mass or less. When the content of the ethylenically unsaturated monomer (B1) is above the lower limit, the viscosity of the model material color composition is easily controlled, and good dischargeability from the nozzle is easily ensured. When the content of the ethylenically unsaturated monomer (B1) is below the upper limit, the resulting model material is easily imparted with high strength and hardness, and its dimensional stability is easily improved.

[0061] The model material color composition included in the model material composition set of the present invention preferably contains, as the ethylenically unsaturated monomer (B), a nitrogen atom-containing ethylenically unsaturated monomer (B2) (hereinafter also simply referred to as "nitrogen atom-containing ethylenically unsaturated monomer (B2)") that is not a (meth)acrylate-based compound. In this specification, the ethylenically unsaturated monomer (B2) is not a (meth)acrylate, and a (meth)acrylate containing a nitrogen atom is not included in the nitrogen atom-containing ethylenically unsaturated monomer (B2).

[0062] The nitrogen atom-containing ethylenically unsaturated monomer (B2) contained in the model material color composition may be a monofunctional nitrogen atom-containing ethylenically unsaturated monomer (monofunctional ethylenically unsaturated monomer) or a polyfunctional nitrogen atom-containing ethylenically unsaturated monomer (polyfunctional ethylenically unsaturated monomer). Examples of the nitrogen atom-containing ethylenically unsaturated monomer (B2) include (meth)acrylamides, N-vinyl lactams, maleimide, and N-vinylformamide. These may be used alone or in combination of two or more.

[0063] As the (meth)acrylamide, a compound represented by the following formula (I): [ka] [In the formula, Q 1 represents an n-valent linking group, and Q 2 each independently represents a hydrogen atom or a monovalent organic group, and R 1 each independently represents a hydrogen atom or a methyl group, and n represents an integer of 1 or 2 or more. and a monofunctional or polyfunctional (meth)acrylamide compound represented by the following formula (II): [ka] [In the formula, Q 3 represents a divalent linking group which may have a substituent and which forms an alicyclic structure together with the N atom, R 1 represents a hydrogen atom or a methyl group] The (meth)acrylamides are preferably monofunctional compounds, from the viewpoint of appropriately lowering the viscosity of the model material color composition and easily improving the dischargeability.

[0064] The monofunctional compound represented by formula (I) or formula (II) includes, for example, Q 1 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, and Q 2is preferably a linear or branched alkyl group having 1 to 10 carbon atoms and / or a hydrogen atom (e.g., N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, etc.); 1 preferably has a linear or branched hydroxyalkyl group having 2 to 10 carbon atoms, and Q 2 hydroxyalkyl(meth)acrylamides in which Q is a hydrogen atom (e.g., hydroxyethylacrylamide, hydroxypropylacrylamide, etc.); 1 preferably has an alicyclic group having 3 to 20 carbon atoms, and Q 2 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms and / or a hydrogen atom; 3 However, preferred examples include (meth)acrylamides having 4 to 20 carbon atoms and constituting an alicyclic group [for example, acryloylmorpholine].

[0065] The N-vinyl lactam may be either monofunctional or polyfunctional, and examples thereof include the following formula (III): [ka] [wherein m represents an integer of 1 to 5] From the viewpoint of easy availability of raw materials, m is preferably an integer of 2 to 4, and more preferably 2 or 4. Specific examples of such N-vinyl lactams include N-vinylpyrrolidone and N-vinylcaprolactam.

[0066] From the viewpoint of easily increasing the strength and hardness of the resulting model material, the model material color composition preferably contains, as the nitrogen atom-containing ethylenically unsaturated monomer (B2), at least one selected from the group consisting of (meth)acrylamides and N-vinyllactams, more preferably (meth)acrylamides, and even more preferably Q in formula (II). 3The (meth)acrylamides having 4 to 20 carbon atoms and constituting an alicyclic group are particularly preferred, and acryloylmorpholine is particularly preferred.

[0067] The content of the nitrogen-atom-containing ethylenically unsaturated monomer (B2) in the model material color composition is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, based on the total mass of the model material color composition, and is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less. When the content of the nitrogen-atom-containing ethylenically unsaturated monomer (B2) is above the lower limit, the resulting model material is easily imparted with high strength and hardness, and dimensional stability is easily improved. Furthermore, when the content of the nitrogen-atom-containing ethylenically unsaturated monomer (B2) is below the upper limit, the viscosity of the model material color composition is easily controlled, and good dischargeability from a nozzle is easily ensured.

[0068] The model material color composition included in the model material composition set of the present invention preferably contains, as the ethylenically unsaturated monomer (B), a monofunctional ethylenically unsaturated monomer and a di- or higher functional ethylenically unsaturated monomer. Examples of the monofunctional ethylenically unsaturated monomer include the monofunctional (meth)acrylates and monofunctional nitrogen-atom-containing ethylenically unsaturated monomers described above. Examples of the di- or higher functional ethylenically unsaturated monomer include the polyfunctional (meth)acrylates and polyfunctional nitrogen-atom-containing ethylenically unsaturated monomers described above. When the model material color composition included in the model material composition set of the present invention contains a di- or higher functional ethylenically unsaturated monomer in addition to the monofunctional ethylenically unsaturated monomer, the toughness and strength of the resulting model material are easily improved.

[0069] The content of the monofunctional ethylenically unsaturated monomer in the model material color composition is preferably 30% by mass or more, more preferably 35% by mass or more, even more preferably 40% by mass or more, and preferably 70% by mass or less, more preferably 65% ​​by mass or less, based on the total mass of the model material color composition. When the content of the monofunctional ethylenically unsaturated monomer in the model material color composition is equal to or greater than the lower limit, the viscosity of the model material color composition is reduced, and the dischargeability is easily improved. When the content of the monofunctional ethylenically unsaturated monomer is equal to or less than the upper limit, the strength and hardness of the resulting model material are easily increased, and the stickiness of the surface of the model material is easily suppressed.

[0070] The content of the difunctional or higher ethylenically unsaturated monomer in the model material color composition is preferably 5% by mass or more, more preferably 8% by mass or more, and even more preferably 10% by mass or more, based on the total mass of the model material color composition, and is also preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less. When the content of the difunctional or higher ethylenically unsaturated monomer in the model material color composition is above the lower limit, the toughness of the resulting model material is likely to be improved, and well-balanced mechanical properties are likely to be imparted to the model material. Furthermore, when the content of the difunctional or higher ethylenically unsaturated monomer is below the upper limit, cure shrinkage during photocuring of the model material color composition is likely to be suppressed, and the dimensional accuracy (or warpage resistance) of the resulting model material is likely to be improved.

[0071] In a preferred embodiment of the present invention, the model material color composition preferably contains the monofunctional (meth)acrylate, preferably having an alicyclic structure, described above, a polyfunctional (meth)acrylate, and a monofunctional nitrogen-containing ethylenically unsaturated monomer. When the model material color composition contains a monofunctional (meth)acrylate having an alicyclic structure and a polyfunctional (meth)acrylate, the viscosity of the composition is reduced, which facilitates improved dischargeability. At the same time, the toughness of the resulting model material is improved, and well-balanced mechanical properties are readily imparted to the model material. Furthermore, when the model material color composition contains a monofunctional nitrogen-containing ethylenically unsaturated monomer, the strength of the resulting model material is readily improved.

[0072] In this embodiment, from the viewpoint of easily achieving the above-mentioned effects, the content of the monofunctional (meth)acrylate having an aliphatic cyclic structure in the model material color composition is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 75% by mass or less, more preferably 60% by mass or less, based on the total mass of the model material color composition. Furthermore, the content of the polyfunctional (meth)acrylate is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 45% by mass or less, based on the total mass of the model material color composition. Furthermore, the content of the monofunctional nitrogen atom-containing ethylenically unsaturated monomer is preferably 5% by mass or more, more preferably 10% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less.

[0073] The model material color composition included in the model material composition set of the present invention preferably further contains a polymerizable oligomer. By including a polymerizable oligomer in the model material color composition, the toughness of the model material is likely to be improved, ensuring well-balanced mechanical strength, resulting in a model material that is less likely to break even when bent. It also tends to reduce the tackiness of the surface of the model material.

[0074] Examples of polymerizable oligomers include epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, and urethane (meth)acrylate oligomers. These may be used alone or in combination of two or more. A polymerizable oligomer that is preferably used is preferably a polymerizable oligomer having a urethane group, more preferably a urethane (meth)acrylate oligomer, from the viewpoints of being able to impart strength and toughness to the resulting model material, and of being able to select materials with a wide range of properties from a wide range of materials.

[0075] The polymerizable oligomer having a urethane group is preferably a caprolactone-modified polymerizable oligomer, from the viewpoints of easily designing the viscosity of the model material color composition to be low, easily increasing the hardness and strength of the resulting model material, and easily reducing cure shrinkage.When the model material color composition contains a polymerizable oligomer, the polymerizable oligomer is preferably a caprolactone-modified isophorone diisocyanate-based polymerizable oligomer, from the viewpoint of easily increasing the hardness and strength of the resulting model material.

[0076] When the model material color composition contains a polymerizable oligomer, the content thereof is preferably 10% by mass or more, more preferably 15% by mass or more, and preferably 45% by mass or less, more preferably 30% by mass or less, based on the total mass of the model material color composition. When the content of the polymerizable oligomer is equal to or greater than the lower limit, the tackiness of the model material surface is easily reduced. When the content of the polymerizable oligomer is equal to or less than the upper limit, the model material color composition can be easily discharged with ease.

[0077] The model material color composition may contain other additives as needed, provided that they do not impair the effects of the present invention. Examples of other additives include photopolymerization initiators, surface conditioners, storage stabilizers, antioxidants, colorants, UV absorbers, light stabilizers, polymerization inhibitors, chain transfer agents, and fillers. These components are not particularly limited, and known compounds conventionally used in the relevant field can be appropriately selected and used. As photopolymerization initiators and storage stabilizers, the same photopolymerization initiators and storage stabilizers as those exemplified above for the model material clear composition can also be suitably used in the model material color composition in the same amounts. The additives contained in the model material clear composition and the additives contained in the model material color composition may be the same or different.

[0078] Examples of surface conditioners that the model material color composition may contain include those listed above as examples of surface conditioners that the model material clear composition may contain. When the model material color composition contains a surface conditioner, the content is preferably 0.005% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.05% by mass or more, based on the total mass of the model material color composition, and is preferably 2% by mass or less, more preferably 1.5% by mass or less, and even more preferably 1% by mass or less. When the content of the surface conditioner is within the above range, it is easy to control the surface tension of the model material color composition within an appropriate range.

[0079] Both the model material clear composition and the model material color composition constituting the model material composition set of the present invention preferably contain a surface conditioner. In this case, the amount of surface conditioner contained in the model material color composition (the content (mass %) of the surface conditioner relative to the total mass of the model material color composition) is preferably less than the amount of surface conditioner contained in the model material clear composition (the content (mass %) of the surface conditioner relative to the total mass of the model material clear composition). If the amount of surface conditioner contained in the model material color composition is less than the amount of surface conditioner contained in the model material clear composition, repulsion between the model material clear composition and the model material color composition at the interface between the two compositions is suppressed. This results in a clearer boundary between the clear model material and the color model material in the resulting model material, allowing for the production of a model material with excellent appearance. In this case, the amount of surface conditioner contained in the model material color composition can be determined appropriately depending on the types and ratios of the polymerizable compounds constituting the model material color composition and the model material clear composition. In one embodiment of the present invention, the amount (mass %) of the surface conditioner contained in the model material color composition is preferably 30% or more, more preferably 35% or more, even more preferably 40% or more, relative to the amount (mass %) of the surface conditioner contained in the model material clear composition of the present invention, and is preferably 85% or less, more preferably 70% or less, even more preferably 60% or less.

[0080] The model material color composition in the model material composition set of the present invention is usually a colored composition containing a pigment. The composition of the model material color composition is not particularly limited, but the composition preferably contains cyan, magenta, and yellow, and more preferably further contains white and / or black.

[0081] From the viewpoints of color tone, color development, and ease of pigment dispersion, cyan preferably contains at least one pigment selected from the group consisting of CI Pigment Blue 15:3 and CI Pigment Blue 15:4.

[0082] From the viewpoints of color tone, color development, and ease of pigment dispersion, it is preferable that the magenta contains at least one pigment selected from the group consisting of CI Pigment Red 122, CI Pigment Red 202, and CI Pigment Violet 19.

[0083] From the viewpoints of color tone, color development, and ease of pigment dispersion, it is preferable that the yellow contains at least one pigment selected from the group consisting of CI Pigment Yellow 150 and CI Pigment Yellow 155.

[0084] From the viewpoints of color tone, hiding power, and ease of pigment dispersion, the white preferably contains titanium oxide. From the viewpoint of easily improving the light stability of the ink, the titanium oxide is more preferably rutile titanium oxide.

[0085] The black preferably contains carbon black from the viewpoints of color tone, color development, and ease of pigment dispersion.

[0086] The content of the pigment in the model material color composition may be appropriately set depending on the desired color of the model material color composition and the type of pigment used, but is usually 0.1% by mass or more, more preferably 0.2% by mass or more, based on the total mass of the model material color composition. There is no particular upper limit to the content of the pigment in the model material color composition, and it is usually 5% by mass or less, preferably 3% by mass or less, based on the total mass of the model material color composition.

[0087] The viscosity of the model material color composition is preferably 1 mPa·s or more and less than 500 mPa·s at 25°C for use in material jet stereolithography. To ensure good dischargeability from the material jet nozzle, the viscosity at 25°C is preferably 10 to 400 mPa·s, and more preferably 20 to 300 mPa·s. The viscosity can be measured in accordance with JIS Z 8803 using an R100 viscometer. The viscosity of the model material color composition can be controlled by adjusting the type and blending ratio of the polymerizable compound, the type and amount of dilution solvent and thickener, etc.

[0088] The surface tension of the model material color composition of the present invention is preferably 24 to 34 mN / m, more preferably 28 to 30 mN / m. When the surface tension is within the above range, droplets can be normally formed from the nozzle even when the material jet is discharged at high speed, making it easier to ensure an appropriate droplet volume and improve modeling accuracy. In the present invention, the surface tension of the model material color composition can be controlled by adjusting the type and amount of the surface conditioner.

[0089] In the present invention, the method for producing the model material color composition is not particularly limited, and the model material color composition can be produced, for example, by uniformly mixing the components constituting the model material color composition using a mixing and stirring device or the like.

[0090] <Material Jet Stereolithography Composition Set> In order to model complex or intricate shapes with high precision, the model material clear composition and / or model material composition set of the present invention is preferably used in combination with a support material for supporting the model material during three-dimensional modeling. Therefore, the present invention also covers a material jet stereolithography composition set comprising the model material clear composition or the model material composition set of the present invention and a support material composition for modeling the support material by material jet stereolithography.

[0091] <Support material composition> The support material composition is a photocurable composition for a support material that provides a support material upon photocuring. After producing a model material, the support material can be removed from the model material by physically peeling it off or by dissolving it in an organic solvent or water. The model material clear composition and model material composition set of the present invention can be used in combination with various compositions conventionally known as support material compositions. The support material composition constituting the stereolithography composition set of the present invention is preferably water-soluble, since this allows for easy removal of the support material without damaging the model material, is environmentally friendly, and allows for clean and detailed removal of the support material.

[0092] Such water-soluble support material compositions include, for example, those containing a monofunctional ethylenically unsaturated monomer and a polyalkylene glycol having an oxyethylene group and / or an oxypropylene group.

[0093] The monofunctional ethylenically unsaturated monomer contained in the support material composition is a polymerizable monomer having one ethylenic double bond in the molecule and capable of being cured by energy rays, and is preferably a water-soluble monofunctional ethylenically unsaturated monomer. Examples of the monofunctional ethylenically unsaturated monomer contained in the support material composition include hydroxyl group-containing (meth)acrylates having 2 to 15 carbon atoms [e.g., hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.], hydroxyl group-containing (meth)acrylates having a number average molecular weight (Mn) of 200 to 1,000 [e.g., polyethylene glycol mono(meth)acrylate, monoalkoxy (carbon number 1 to 4) polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, monoalkoxy (carbon number 1 to 4) polypropylene glycol mono(meth)acrylate, etc.], and the like. (meth)acrylate, mono(meth)acrylate of PEG-PPG block polymer, etc.), (meth)acrylamide derivatives having 3 to 15 carbon atoms [for example, (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl(meth)acrylamide, N-butyl(meth)acrylamide, N,N'-dimethyl(meth)acrylamide, N,N'-diethyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N-hydroxypropyl(meth)acrylamide, N-hydroxybutyl(meth)acrylamide, etc.], (meth)acryloylmorpholine, etc. These may be used alone or in combination of two or more.

[0094] The content of the monofunctional ethylenically unsaturated monomer in the support material composition is preferably 20% by mass or more, more preferably 25% by mass or more, based on the total amount of the support material composition, from the viewpoints of improving the curability of the support material composition and facilitating rapid dissolution in water of the support material obtained by photocuring the support material composition. Furthermore, the content is preferably 50% by mass or less, more preferably 45% by mass or less.

[0095] The support material composition preferably contains a polyalkylene glycol containing an oxyethylene group and / or an oxypropylene group. The polyalkylene glycol containing an oxyethylene group and / or an oxypropylene group is an active hydrogen compound to which at least ethylene oxide and / or propylene oxide has been added. Examples of polyalkylene glycols include polyethylene glycol and polypropylene glycol. These may be used alone or in combination of two or more. Examples of active hydrogen compounds include monohydric to tetrahydric alcohols and amine compounds. Among these, dihydric alcohols or water are preferred.

[0096] The content of the polyalkylene glycol in the support material composition is preferably 20% by mass or more, more preferably 25% by mass or more, based on the total amount of the support material composition, from the viewpoint of easily increasing the solubility in water of the support material obtained by photocuring the support material composition. Furthermore, the content is preferably 49% by mass or less, more preferably 45% by mass or less, from the viewpoint of easily preventing the phenomenon of polyalkylene glycol leaching out of the support material during the modeling of a three-dimensional object and easily increasing the precision of the modeling.

[0097] The number average molecular weight (M n ) of the polyalkylene glycol is preferably 100 to 5,000. n When (M) of the polyalkylene glycol is within the above range, the polyalkylene glycol is compatible with the polyalkylene glycol before photocuring, but is poorly compatible with the polyalkylene glycol after photocuring. As a result, the support material obtained by photocuring the support material composition can have improved self-supporting properties and can also have improved solubility in water. n ) is preferably 200 to 3,000, more preferably 400 to 2,000.

[0098] The support material composition may contain other additives as needed, such as a photopolymerization initiator, a water-soluble organic solvent, an antioxidant, a colorant, a pigment dispersant, a storage stabilizer, an ultraviolet absorber, a light stabilizer, a polymerization inhibitor, a chain transfer agent, and a filler.

[0099] The photopolymerization initiator may be the same as the compounds exemplified above as photopolymerization initiators that can be contained in the model material clear composition. When the support material composition contains a photopolymerization initiator, the content is preferably 2% by mass or more, more preferably 3% by mass or more, and preferably 20% by mass or less, more preferably 10% by mass or less, based on the total amount of the support material composition. When the content of the photopolymerization initiator is within the above range, unreacted polymerization components are reduced, making it easy to sufficiently enhance the curability of the support material.

[0100] The water-soluble organic solvent is a component that improves the solubility in water of the support material obtained by photocuring the support material composition. It is also a component that can adjust the viscosity of the support material composition to a low level. When the support material composition contains a water-soluble organic solvent, the content is preferably 35% by mass or less, more preferably 30% by mass or less, based on the total amount of the support material composition. Furthermore, the content is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. If the amount of water-soluble organic solvent in the support material composition is too high, the water-soluble organic solvent may seep out when the support material composition is photocured, which may result in a deterioration in the dimensional accuracy of the model material formed on the upper layer of the support material. When the content of the water-soluble organic solvent is equal to or less than the above-mentioned upper limit, such seepage is easily suppressed. When the content of the water-soluble organic solvent in the support material composition is equal to or greater than the above-mentioned lower limit, it is easy to improve the removability of the support material with water and to control the viscosity of the support material composition to a low level.

[0101] Examples of the water-soluble organic solvent include alkylene glycol monoacetates having a linear or branched alkylene group [e.g., ethylene glycol monoacetate, propylene glycol monoacetate, diethylene glycol monoacetate, dipropylene glycol monoacetate, triethylene glycol monoacetate, tripropylene glycol monoacetate, tetraethylene glycol monoacetate, tetrapropylene glycol monoacetate, etc.], alkylene glycol monoalkyl ethers having a linear or branched alkylene group [e.g., ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, dipropylene glycol monomethyl ether, triethylene glycol monomethyl ether, tripropylene glycol monomethyl ether, tetraethylene glycol monomethyl ether, tetrapropylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monoethyl ether, diethylene glycol monoethyl ether, dipropylene glycol monoethyl ether, ethyl ether, triethylene glycol monoethyl ether, tripropylene glycol monoethyl ether, tetraethylene glycol monoethyl ether, tetrapropylene glycol monoethyl ether, ethylene glycol monopropyl ether, propylene glycol monopropyl ether, diethylene glycol monopropyl ether, dipropylene glycol monopropyl ether, triethylene glycol monopropyl ether, tripropylene glycol monopropyl ether, tetraethylene glycol monopropyl ether, tetrapropylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monobutyl ether, diethylene glycol monobutyl ether, dipropylene glycol monobutyl ether, triethylene glycol monobutyl ether, tripropylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, tetrapropylene glycol monobutyl ether, etc.], alkylene glycol diacetates having a linear or branched alkylene group [for example, ethylene glycol diacetate,propylene glycol diacetate, diethylene glycol diacetate, dipropylene glycol diacetate, triethylene glycol diacetate, tripropylene glycol diacetate, tetraethylene glycol diacetate, tetrapropylene glycol diacetate, etc.], alkylene glycol dialkyl ethers having a linear or branched alkylene group [for example, ethylene glycol dimethyl ether, propylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, triethylene glycol dimethyl ether, tripropylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, tetrapropylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol diethyl ether, diethylene glycol diethyl ether, dipropylene glycol diethyl ether, triethylene glycol diethyl ether, tripropylene glycol diethyl ether, tetraethylene glycol diethyl ether, tetrapropylene glycol diethyl ether, ethylene glycol ethanol dipropyl ether, propylene glycol dipropyl ether, diethylene glycol dipropyl ether, dipropylene glycol dipropyl ether, triethylene glycol dipropyl ether, tripropylene glycol dipropyl ether, tetraethylene glycol dipropyl ether, tetrapropylene glycol dipropyl ether, ethylene glycol dibutyl ether, propylene glycol dibutyl ether, diethylene glycol dibutyl ether, dipropylene glycol dibutyl ether, triethylene glycol dibutyl ether, tripropylene glycol dibutyl ether, tetraethylene glycol dibutyl ether, tetrapropylene glycol dibutyl ether, etc.], alkylene glycol monoalkyl ether acetates having a linear or branched alkylene group [for example, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate,Tripropylene glycol monomethyl ether acetate, tetraethylene glycol monomethyl ether acetate, tetrapropylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene glycol monoethyl ether acetate, triethylene glycol monoethyl ether acetate, tripropylene glycol monoethyl ether acetate, tetraethylene glycol monoethyl ether acetate, tetrapropylene glycol monoethyl ether acetate, ethylene glycol monopropyl ether acetate, propylene glycol monopropyl ether acetate, diethylene glycol monopropyl ether acetate acetate, dipropylene glycol monopropyl ether acetate, triethylene glycol monopropyl ether acetate, tripropylene glycol monopropyl ether acetate, tetraethylene glycol monopropyl ether acetate, tetrapropylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, propylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monobutyl ether acetate, triethylene glycol monobutyl ether acetate, tripropylene glycol monobutyl ether acetate, tetraethylene glycol monobutyl ether acetate, tetrapropylene glycol monobutyl ether acetate, etc. These may be used alone or in combination of two or more. Among these, from the viewpoints of easily improving the removability of the support material with water and easily controlling the viscosity of the support material composition to be low, it is more preferable that the water-soluble organic solvent be triethylene glycol monomethyl ether or dipropylene glycol monomethyl ether acetate.

[0102] From the viewpoint of improving dischargeability from the material jet nozzle, the viscosity of the support material composition in the present invention is preferably 1 to 500 mPa·s, and more preferably 10 to 400 mPa·s at 25° C. The viscosity can be measured in accordance with JIS Z 8 803 using an R100 type viscometer.

[0103] In the present invention, the method for producing the support material composition is not particularly limited, and the support material composition can be produced, for example, by uniformly mixing the components that make up the support material composition using a mixer or stirrer.

[0104] <Method of manufacturing a stereolithography object> Using the model material clear composition, model material composition set, or material jet stereolithography composition set of the present invention, a three-dimensional object (model material) can be produced by a material jet type stereolithography method.

[0105] The method for producing a stereolithography object is not particularly limited as long as it is a method for producing a three-dimensional object by a material jet stereolithography method using the model material clear composition, model material composition set, or stereolithography composition set of the present invention, and any known method can be used. For example, a three-dimensional model material can be obtained by a method including the steps of photocuring the model material clear composition (and model material color composition) to obtain a model material, photocuring the support material composition to obtain a support material, and removing the support material from the model material.

[0106] In the manufacturing method, for example, based on 3D CAD data of the object to be produced, data on the model material clear composition (and model material color composition) that will be layered using the material jet method to form the three-dimensional object, and data on the support material composition that will support the three-dimensional object in the process of being produced, are prepared; slice data for discharging each composition using a material jet 3D printer is then prepared; the compositions for the model material and the support material are then discharged based on the prepared slice data, and a photocuring process is then repeated for each layer, thereby producing a photo-fabricated object consisting of a cured product (model material) of the model material clear composition (and model material color composition) and a cured product (support material) of the support material composition.

[0107] Examples of light for curing the model material clear composition (and model material color composition) and the support material composition include active energy rays such as far infrared rays, infrared rays, visible light, near ultraviolet rays, ultraviolet rays, electron beams, α rays, γ rays, and X-rays. Among these, near ultraviolet rays or ultraviolet rays are preferred from the viewpoint of ease and efficiency of the curing operation.

[0108] Examples of light sources include conventionally known high-pressure mercury lamps, metal halide lamps, and UV-LEDs. Among these, LEDs are preferred from the viewpoints of miniaturizing the equipment and reducing power consumption. The light intensity is set to 200 to 500 mJ / cm from the viewpoints of hardness and dimensional accuracy of the model material. 2 When a UV-LED is used as the light source, it is preferable to use one with a central wavelength of 385 to 415 nm, since this allows the light to reach deep layers more easily and improves the hardness and dimensional accuracy of the resulting model material.

[0109] The thickness of each layer constituting the three-dimensional object is preferably thin from the viewpoint of modeling accuracy, but is preferably 5 to 30 μm in terms of the balance with modeling speed.

[0110] The resulting three-dimensional object is a combination of model material and support material. The support material can be removed from the three-dimensional object to obtain a three-dimensional object that is the model material. The support material is preferably removed by, for example, immersing the resulting three-dimensional object in a removal solvent that dissolves the support material, softening the support material, and then removing the support material from the surface of the model material with a brush or the like. The solvent for removing the support material may be water or a water-soluble solvent, such as a glycol-based solvent or an alcohol-based solvent. These may be used alone or in combination of two or more.

[0111] The above steps result in a three-dimensional object made of the model material. The three-dimensional object manufactured using the model material clear composition, model material composition set, or stereolithography composition set of the present invention exhibits reduced color change (yellowing) due to light irradiation, high transparency, and well-balanced mechanical properties. [Example]

[0112] The present invention will be described in more detail below with reference to examples. In the examples, "%" and "parts" are by mass % and parts by mass unless otherwise specified.

[0113] 1. Model material clear composition Table 1 shows details of the components constituting the model material clear composition used in the examples and comparative examples.

[0114] [Table 1]

[0115] (1) Preparation of model material clear composition According to the compositions shown in Table 2, the components constituting each model material clear composition were uniformly mixed and stirred using a mixer / stirrer to prepare the model material clear compositions of Examples 1 to 16 and Comparative Examples 1 to 5.

[0116] [Table 2] JPEG0007735252000005.jpg25097

[0117] (2) Evaluation of the physical properties and characteristics of the cured product of the model material clear composition Cured products (clear model materials) were prepared from the clear model material compositions prepared in the above Examples and Comparative Examples, and the physical properties and characteristics of each cured product were evaluated according to the methods described below. The results are shown in Table 3.

[0118] <Measurement of tensile strength> The clear model material compositions prepared in the examples and comparative examples were each molded using a UV-curable inkjet molding device in accordance with the multipurpose test piece type A1 shape specified in JIS K 7139:2009 "Plastics - Test pieces." The tensile strength of these test pieces was measured in accordance with JIS K7162:1994 "Plastics - Test methods for tensile properties, Part 2: Test conditions for molded, extruded, and cast plastics" (molding conditions: 1 layer thickness 32 μm, illuminance 1000 mW / cm). 2 , 1 layer integrated light intensity 800mJ / cm 2 ).

[0119] The measured tensile strength was evaluated according to the following evaluation criteria. [Evaluation criteria] ○: A value of 30 MPa or more was shown. △: A value of 20 MPa or more and less than 30 MPa was shown. ×: A value of less than 20 MPa was shown.

[0120] <Shore D hardness measurement> Two samples were formed in accordance with the rectangular test piece shape B2 specified in JIS K 7139:2009 "Plastics - Test pieces" using the same forming equipment and conditions as used to measure the tensile strength. These were stacked in two layers to form the measurement specimen, and the Shore D hardness was measured in accordance with JIS K7215:1986 "Durometer hardness test method for plastics."

[0121] The measured Shore D hardness was evaluated according to the following evaluation criteria. [Evaluation criteria] 〇: Values ​​of 50 or higher were shown. △: A value of 30 or more and less than 50 was shown. ×: A value of less than 30 was shown.

[0122] <Evaluation of the color of model materials> Lab color difference measurements were performed according to the following procedure to evaluate the color of the clear model material. Lab color difference measurement: From the model material clear compositions prepared in the examples and comparative examples, plates with a thickness of 2 mm were molded using a UV-curable inkjet molding device, and used as measurement samples (molding conditions: one layer thickness of 32 μm, illuminance of 1000 mW / cm). 2 , 1 layer integrated light intensity 800mJ / cm 2 The Lab color difference of this sample was measured using a color difference meter "X-Rite 939" (manufactured by X-Rite).

[0123] Based on the measured Lab color difference b*, the color of the model material was evaluated according to the following evaluation criteria. [Evaluation criteria] ○: The b* value was less than 5. △: The b* value was 5 or more and less than 10. ×: The b* value was 10 or more.

[0124] [Table 3] JPEG0007735252000006.jpg24424

[0125] It has been confirmed that the clear model material composition according to the present invention has little yellowness, excellent transparency, and a certain level of strength and hardness.

[0126] 2. Model Material Composition Set (1) Preparation of model material color composition Table 4 shows the details of the components constituting the model material color composition used in the production examples.

[0127] [Table 4]

[0128] According to the formulations shown in Table 5, the components constituting each model material color composition were uniformly mixed and stirred using a mixer / stirrer to prepare model material color compositions of Production Examples 1 to 10.

[0129] (2) Evaluation of the physical properties and characteristics of the cured product of the model material color composition Cured products (color model materials) were prepared from the model material color compositions prepared in the above manufacturing examples, and the tensile strength and Shore D hardness of each cured product were measured and evaluated using the same procedures and evaluation criteria as those used for the model material clear composition in the above examples. The results are shown in Table 5.

[0130] [Table 5]

[0131] (3) Evaluation of model material composition sets Using the model material clear compositions prepared in Examples 2 and 5 above and the model material color compositions prepared in Production Examples 1 to 5 above, bleeding at the interface between the model material clear composition and the model material color composition was evaluated according to the following method.

[0132] <Breeding evaluation method> Using a micropipette, 0.02 mL of each of the model material clear composition prepared in Example 2 and the model material color composition prepared in Production Example 1 was dropped onto a polyethylene terephthalate film (A4300, manufactured by Toyobo Co., Ltd., 100 mm x 150 mm x 188 μm thick) so that the distance between the centers of the droplets was 5 mm and the droplets remained separate. The droplets then gradually spread and, after approximately 10 seconds, merged. The state of the interface between the droplets was visually observed from above to evaluate bleeding. Bleeding was evaluated using the same procedure as above for the combination of the model material clear composition of Example 2 with each of the model material color compositions of Production Examples 2 to 10, and for the combination of the model material clear composition of Example 5 with each of the model material color compositions of Production Examples 1 to 10. As a result, in all of the combinations, the interface between the layer of model material clear composition and the layer of model material color composition was linear in top view, confirming the absence of bleeding.

[0133] Furthermore, bleeding was evaluated in the same manner as above for the combinations of the model material clear composition prepared in Example 12 and each of the model material color compositions prepared in Production Examples 1 to 10. As a result, for each of the combinations, slight bleeding was observed at the interface between the layer made of the model material clear composition and the layer made of the model material color composition.

Claims

1. A clear model material composition for use in a material jet stereolithography method, comprising an ethylenically unsaturated compound (A) and a photopolymerization initiator, The ethylenically unsaturated compound (A) is Ethylenically unsaturated monomers (A1) having a dicyclopentenyl group and / or a dicyclopentanyl group; an ethylenically unsaturated compound (A2) having an aliphatic cyclic structure and a urethane group in the molecule; and An ethylenically unsaturated monomer (A3) having an aliphatic cyclic structure in the molecule and not having a urethane group or an amide group (excluding the ethylenically unsaturated monomer (A1)). Including, the total mass of the ethylenically unsaturated monomer (A1), the ethylenically unsaturated compound (A2), and the ethylenically unsaturated monomer (A3) is 60 mass% or more based on the total mass of the ethylenically unsaturated compound (A); the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated compound (A2) [ethylenically unsaturated monomer (A1) / ethylenically unsaturated compound (A2)] is 1.1 or more and 10 or less; the mass ratio of the ethylenically unsaturated monomer (A1) to the ethylenically unsaturated monomer (A3) [ethylenically unsaturated monomer (A1) / ethylenically unsaturated monomer (A3)] is 1.8 or more and 10 or less; Model material clear composition.

2. 2. The model material clear composition according to claim 1, comprising 30% by mass or more of the ethylenically unsaturated monomer (A1) relative to the total mass of the ethylenically unsaturated compound (A).

3. 3. The model material clear composition according to claim 1, wherein the ethylenically unsaturated monomer (A3) is an ethylenically unsaturated monomer that does not have a urethane group, an amide group, an aromatic group, or a vinyl ether group.

4. The model material clear composition according to any one of claims 1 to 3, wherein the ethylenically unsaturated monomer (A3) has at least one group selected from the group consisting of a cyclohexyl group, a 4-t-butylcyclohexyl group, a 3,5,5-trimethylcyclohexyl group, an isobornyl group, a tricyclodecanyl group, a dicyclopentadienyl group, and a 1,4-cyclohexanedimethanol group.

5. The model material clear composition according to any one of claims 1 to 4, comprising 10 mass% or more of the ethylenically unsaturated compound (A2) relative to the total mass of the ethylenically unsaturated compound (A).

6. The model material clear composition according to any one of claims 1 to 5, comprising an ethylenically unsaturated monomer having a nitrogen atom in the molecule and not having an aliphatic cyclic structure in an amount of 12 mass% or less relative to the total mass of the ethylenically unsaturated compound (A).

7. A model material composition set for use in a material jet stereolithography method, comprising the model material clear composition according to any one of claims 1 to 6 and a model material color composition containing an ethylenically unsaturated monomer (B).

8. The model material color composition according to claim 7, comprising 30% by mass or more and 85% by mass or less of a (meth)acrylate-based ethylenically unsaturated monomer (B1) and 10% by mass or more and 50% by mass or less of a nitrogen atom-containing ethylenically unsaturated monomer (B2) that is not a (meth)acrylate-based compound, based on the total mass of the model material color composition.

9. The model material composition set according to claim 8, wherein the nitrogen atom-containing ethylenically unsaturated monomer (B2) that is not a (meth)acrylate compound is selected from the group consisting of (meth)acrylamides and N-vinyllactams.

10. The model material color composition contains a monofunctional ethylenically unsaturated monomer and a difunctional or higher functional ethylenically unsaturated monomer as the ethylenically unsaturated monomer (B), the model material composition set according to any one of claims 7 to 9.

11. The model material color composition according to any one of claims 8 to 10, wherein the (meth)acrylate-based ethylenically unsaturated monomer (B1) is a (meth)acrylate-based ethylenically unsaturated monomer having an aliphatic cyclic structure and / or an aromatic cyclic structure.

12. The model material composition set according to any one of claims 7 to 11, wherein the model material color composition comprises cyan, magenta, and yellow.

13. The model material composition set according to claim 12, wherein the model material color composition further comprises white and / or black.

14. The model material composition set according to any one of claims 7 to 13, wherein both the model material clear composition and the model material color composition contain a surface conditioner.

15. The model material composition set according to claim 14, wherein the content (mass %) of the surface conditioner contained in the model material clear composition relative to the total mass of the model material clear composition is greater than the content (mass %) of the surface conditioner contained in the model material color composition relative to the total mass of the model material color composition.

16. A material jet stereolithography composition set comprising the model material clear composition according to any one of claims 1 to 6 or the model material composition set according to any one of claims 7 to 15, and a support material composition for forming a support material by material jet stereolithography.

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