JP7180666B2 - RESIN COMPOSITION, METHOD FOR MANUFACTURING 3D PRODUCT USING THE SAME, AND 3D PRODUCT - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin composition, a method for producing a three-dimensional object using the same, and a three-dimensional object.

In recent years, various methods have been developed that can relatively easily manufacture a three-dimensional object with a complicated shape. As one method for producing a three-dimensional object, there is a method of selectively irradiating a resin composition that is cured by an active energy ray with an active energy ray (for example, ultraviolet light) to cure the resin composition into a desired shape. Are known.

However, when three-dimensional modeling is performed using a resin composition that mainly contains a photopolymerizable compound, there is a problem that the resin composition tends to shrink during curing, and warping tends to occur. In response to such problems, it has been proposed to suppress warpage by, for example, mixing a photopolymerizable compound and a thermally polymerizable compound, and further performing heat curing after photocuring (for example, Patent Document 1). .

In recent years, as a new method for producing a three-dimensional object, a method of continuously or intermittently curing a liquid resin composition containing a photopolymerizable compound has been proposed (Patent Documents 2 and 3). In this method, first, a buffer region in which the resin composition is not cured even when irradiated with active energy rays and a curing region in which the resin composition is cured by irradiation with active energy rays are provided in the tank for the modeled object. At this time, the regions are formed such that the buffer region is located on the bottom side of the modeling tank, and the hardening region is located on the top side of the modeling tank. Then, a carrier serving as a starting point for three-dimensional modeling is placed in the curing region, and the curing region is selectively irradiated with active energy rays from the buffer region (bottom of the modeling tank). As a result, a part of the three-dimensional object (cured product of the resin composition) is formed on the carrier surface. Furthermore, by continuously irradiating the active energy ray while pulling up the carrier to the upper side of the modeling tank, the cured product of the resin composition is continuously formed below the carrier, resulting in a seamless three-dimensional model. is produced.

JP-A-2-24127 Japanese Patent Publication No. 2016-509962 Japanese Patent Application Publication No. 2016-509964

In general, thermally polymerizable compounds often have molecular structures that are easily decomposed or cleaved by ultraviolet light or the like. Therefore, as in Patent Document 1 above, when a photopolymerizable compound and a thermally polymerizable compound are mixed and the resin composition is cured with ultraviolet light, the thermally polymerizable compound is easily decomposed, and the desired effect of suppressing warpage can be obtained. was difficult to obtain. Moreover, in order to improve the light resistance of the thermopolymerizable resin, it is conceivable to add an ultraviolet absorber to the resin composition. However, in the method of selectively irradiating an active energy ray to produce a three-dimensional object, for example, as in Patent Documents 2 and 3, the resin composition is required to have high sensitivity to the active energy ray. Therefore, when the resin composition contains an ultraviolet light absorber, the curing of the photopolymerizable compound tends to be insufficient, and there is a problem that the strength of the obtained three-dimensional object tends to decrease.

The present invention has been made in view of such problems. That is, an object of the present invention is to provide a shaped article that has little warpage, high strength, and good light resistance.

A first aspect of the present invention resides in the following resin composition.
[1] A resin composition used in a method for producing a three-dimensional object made of a cured product of the resin composition by selectively irradiating a liquid resin composition with visible light, the resin composition being photopolymerizable A resin composition comprising a compound, a thermally polymerizable compound, a visible light polymerization initiator, and an ultraviolet light absorber.

[2] The photopolymerizable compound and/or the thermally polymerizable compound contains in its molecule at least one structure selected from the group consisting of an aromatic ring, a triazine ring, an ester bond, a urethane bond, and a urea bond. The resin composition according to [1].
[3] The resin composition according to [1] or [2], wherein the visible light polymerization initiator has an absorption maximum in a wavelength region of 400 nm or longer.
[4] The resin composition according to any one of [1] to [3], further comprising a light stabilizer.
[5] The resin composition according to any one of [1] to [4], further comprising a filler.

The second aspect of the present invention resides in the following three-dimensional molded article manufacturing method and three-dimensional molded article.
[6] A stereolithography step of selectively irradiating the resin composition according to any one of the above [1] to [5] with visible light to form a primary cured product containing a cured product of the photopolymerizable compound. A method for manufacturing a three-dimensional object, comprising:
[7] The method for producing a three-dimensional object according to [6], including a thermosetting step of further thermosetting the primary cured product.
[8] The method for producing a three-dimensional object according to [7], including a light irradiation step of further irradiating the primary cured product with visible light before the heat curing step.

[9] The stereolithography step includes at least a buffer region containing the resin composition and oxygen, where the oxygen inhibits curing of the photopolymerizable compound, and the resin composition, wherein the oxygen concentration is higher than that of the buffer region. a first step of forming a curing region adjacent to and in a modeled article tank which is low and capable of curing the photopolymerizable compound; and selectively irradiating the resin composition with visible light from the buffer region side. and a second step of curing the photopolymerizable compound in the curing region, and in the second step, while moving the formed cured product to the side opposite to the buffer region, The method for producing a three-dimensional object according to any one of [6] to [8], wherein the curing region is continuously irradiated with visible light to form the primary cured product.
[10] A three-dimensional object, which is a cured product of the resin composition according to any one of [1] to [5] above.

INDUSTRIAL APPLICABILITY According to the resin composition of the present invention, it is possible to provide a three-dimensional object with less warpage, high strength, and excellent light resistance.

FIG. 1 is a schematic diagram of a three-dimensional object manufacturing apparatus according to one embodiment of the present invention. FIG. 2 is a schematic diagram of a three-dimensional object manufacturing apparatus according to another embodiment of the present invention.

1. Resin Composition The resin composition of the present invention is in a liquid form, and is used in a method for producing a three-dimensional object by selectively irradiating the resin composition with visible light. In the present invention, visible light refers to wavelengths in the range of 400 nm to 780 nm. As described above, when such a resin composition mainly contains a photopolymerizable compound, there is a problem that the obtained three-dimensional object tends to warp. Conventionally, it has been proposed to add a thermally polymerizable resin to such a resin composition, but the thermally polymerizable resin deteriorates due to ultraviolet light irradiation during modeling. Warpage could not be sufficiently suppressed. Moreover, when an ultraviolet light absorber is added to such a resin composition, the curing of the photopolymerizable compound is inhibited, and the strength of the resulting three-dimensional object tends to be low. Therefore, it has been desired to provide a resin composition that can produce a three-dimensionally shaped article with little warpage, high strength, and good light resistance.

In contrast, the resin composition of the present invention contains a photopolymerizable compound, a thermally polymerizable compound, a visible light polymerization initiator, and an ultraviolet light absorber. Since the resin composition contains a visible light polymerization initiator, it can be cured with visible light. Moreover, at this time, the light (visible light) for curing is hardly absorbed by the ultraviolet light absorber, and the photocurability tends to be good. In addition, even if the thermally polymerizable compound has a structure that is easily degraded by light, it is difficult to be degraded by irradiation with visible light. you get something. In addition, since the resin composition of the present invention contains an ultraviolet absorber, it is possible to suppress photodegradation over time after the three-dimensionally shaped article.

In addition, when the photopolymerizable compound and/or thermally polymerizable compound has a structure selected from the group consisting of an aromatic ring, a triazine ring, an ester bond, a urethane bond, and a urea bond in its molecule, stereolithography Things become more susceptible to photodegradation. On the other hand, with the composition of the resin composition of the present invention, even if the photopolymerizable compound or the thermally polymerizable compound has such a structure, the light resistance of the three-dimensional object can be maintained for a long period of time. has the advantage of being better.

If necessary, the resin composition contains components other than photopolymerizable compounds, thermally polymerizable compounds, visible light polymerization initiators, and ultraviolet light absorbers, such as curing agents, light stabilizers, and fillers. may Each component will be described below.

1-1. Photopolymerizable compound The photopolymerizable compound contained in the resin composition may be a compound that is liquid at room temperature and polymerizable by irradiation with visible light, and may be a monomer or an oligomer. , a prepolymer, or a mixture thereof. Moreover, the photopolymerizable compound may be a radically polymerizable compound or a cationically polymerizable compound. However, as will be described later, in the resin composition used in the method of producing a three-dimensional object while adding oxygen to the resin composition (hereinafter also referred to as "CLIP method"), the photopolymerizable compound is a radically polymerizable compound. must be. The resin composition may contain only one type of photopolymerizable compound, or may contain two or more types.

The type of the radically polymerizable compound is not particularly limited as long as it has a group capable of being radically polymerized by visible light irradiation in the presence of a visible light polymerization initiator (radical polymerization initiator) described later. Examples of radically polymerizable compounds include ethylene group, propenyl group, butenyl group, vinylphenyl group, allyl ether group, vinyl ether group, maleyl group, maleimide group, (meth)acrylamide group, acetylvinyl group, vinylamide group, (meth) ) compounds having one or more acryloyl groups in the molecule.

Among these, the radical polymerizable compound is an unsaturated carboxylic acid ester compound containing one or more unsaturated carboxylic acid ester structures in the molecule, or an unsaturated carboxylic acid ester compound containing one or more unsaturated carboxylic acid amide structures in the molecule, which will be described later. A carboxylic acid amide compound is preferred. Furthermore, (meth)acrylate compounds and/or (meth)acrylamide compounds containing (meth)acryloyl groups, which will be described later, are particularly preferred. In this specification, the term "(meth)acrylic" means methacrylic and/or acrylic, and the term "(meth)acryloyl" means methacryloyl and/or acryloyl, and "(meth)acrylate ” denotes methacrylate and/or acrylate.

Examples of the "compound having an allyl ether group" which is one of the radically polymerizable compounds include phenyl allyl ether, o-, m-, p-cresol monoallyl ether, biphenyl-2-ol monoallyl ether, biphenyl- 4-ol monoallyl ether, butyl allyl ether, cyclohexyl allyl ether, cyclohexanemethanol monoallyl ether, phthalate diallyl ether, isophthalate diallyl ether, dimethanoltricyclodecane diallyl ether, 1,4-cyclohexanedimethanol diallyl ether, alkylene (C2-5) glycol diallyl ether, polyethylene glycol diallyl ether, glycerin diallyl ether, trimethylolpropane diallyl ether, pentaerythritol diallyl ether, polyglycerin (degree of polymerization: 2-5) diallyl ether, trimethylolpropane triallyl ether, Examples include glycerin triallyl ether, pentaerythritol tetraallyl ether and tetraallyloxyethane, pentaerythritol triallyl ether, diglycerin triallyl ether, sorbitol triallyl ether and polyglycerin (degree of polymerization 3-13) polyallyl ether.

Examples of "compounds having a vinyl ether group" include butyl vinyl ether, butyl propenyl ether, butyl butenyl ether, hexyl vinyl ether, 1,4-butanediol divinyl ether, ethylhexyl vinyl ether, phenyl vinyl ether, benzyl vinyl ether, ethyl ethoxy vinyl ether. , acetylethoxyethoxy vinyl ether, cyclohexyl vinyl ether, tricyclodecane vinyl ether, adamantyl vinyl ether, cyclohexanedimethanol divinyl ether, tricyclodecane dimethanol divinyl ether, EO adduct divinyl ether of bisphenol A, cyclohexanediol divinyl ether, cyclopentadiene vinyl ether, nor bornyl dimethanol divinyl ether, divinyl resorcinol, divinyl hydroquinone, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol vinyl ether, butylene divinyl ether, dibutylene glycol divinyl ether, 4- Cyclohexane divinyl ether, oxanorbonane divinyl ether, neopentyl glycol divinyl ether, glycerin trivinyl ether, oxetane divinyl ether, glycerin ethylene oxide adduct trivinyl ether (addition mole number of ethylene oxide: 6), trimethylolpropane trivinyl ether, trivinyl ether ethylene oxide adduct Trivinyl ether (addition mole number of ethylene oxide: 3), pentaerythritol trivinyl ether, ditrimethylolpropane hexavinyl ether and their oxyethylene adducts are included.

Examples of the "compound having a maleimide group" include phenylmaleimide, cyclohexylmaleimide, n-hexylmaleimide and the like.

Examples of "compounds having a (meth)acrylamide group", that is, (meth)acrylamide compounds include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-ethyl(meth)acrylamide, N- isopropyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-butyl (meth)acrylamide, isobutoxymethyl (meth)acrylamide, diacetone (meth)acrylamide, bismethylene acrylamide, di(ethyleneoxy)bispropylacrylamide, and tri(ethyleneoxy)bispropylacrylamide, (meth)acryloylmorpholine and the like.

On the other hand, examples of the above-mentioned "compound having a (meth)acrylic group", i.e., (meth)acrylate compounds, include isoamyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, butyl (meth)acrylate, Pentyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, tridecyl (meth)acrylate, isomyrstyl (meth)acrylate, isostearyl (Meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentenyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 2-ethylhexyl- Diglycol (meth)acrylate, 2-(meth)acryloyloxyethylhexahydrophthalic acid, methoxyethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethyleneglycol (meth)acrylate, methoxydiethyleneglycol (meth)acrylate, Methoxy polyethylene glycol (meth) acrylate, methoxy propylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, pentachlorophenyl (meth) acrylate, pentabromophenyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, dicyclopentanyl (Meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, glycerin (meth) acrylate, 7-amino-3,7-dimethyloctyl ( meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, benzyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 2-ethylhexylcarbitol (meth)acrylate, 2-(meth)acryloyloxyethyl succinate, 2-(meth)acryloyloxyethyl phthalate, 2- (me t) monofunctional (meth)acrylate monomers including acryloyloxyethyl-2-hydroxyethyl-phthalic acid, 2-(meth)acryloyloxyethylhexahydrophthalic acid, and t-butylcyclohexyl (meth)acrylate;
triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, 1,4-butanediol di (meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, cyclohexanedi(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, neopentyl glycol di( meth)acrylate, tricyclodecanediyldimethylene di(meth)acrylate, dimethylol-tricyclodecanedi(meth)acrylate, polyester di(meth)acrylate, PO adduct di(meth)acrylate of bisphenol A, neopentyl hydroxypivalate Bifunctional including glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and tricyclodecanedimethanol di(meth)acrylate, etc. (meth)acrylate monomers of;
Trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate Tri- or higher functional (meth)acrylate monomers, including acrylates, dipentaerythritol monohydroxy penta(meth)acrylate, glycerol propoxy tri(meth)acrylate, and pentaerythritol ethoxytetra(meth)acrylate;
and oligomers thereof.

Further, the "(meth)acrylate-based compound" may be a further modified (modified product) of various (meth)acrylate monomers or oligomers thereof. Examples of modified substances include triethylene glycol diacrylate, polyethylene glycol diacrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, ethylene oxide-modified pentaerythritol tetraacrylate, ethylene oxide-modified bisphenol A di(meth)acrylate, ethylene Ethylene oxide-modified (meth)acrylate monomers such as oxide-modified nonylphenol (meth)acrylate; tripropylene glycol diacrylate, polypropylene glycol diacrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, propylene oxide-modified pentaerythritol tetraacrylate, propylene Propylene oxide-modified (meth)acrylate monomers such as oxide-modified glycerin tri(meth)acrylate; caprolactone-modified (meth)acrylate monomers such as caprolactone-modified trimethylolpropane tri(meth)acrylate; caprolactam-modified dipentaerythritol hexa(meth)acrylate, etc. caprolactam-modified (meth)acrylate monomer;

The "(meth)acrylate-based compound" may also be a compound (hereinafter also referred to as "modified (meth)acrylate-based compound") in which various oligomers are (meth)acrylated. Examples of such modified (meth)acrylate compounds include polybutadiene (meth)acrylate compounds, polyisoprene (meth)acrylate compounds, epoxy (meth)acrylate compounds, urethane (meth)acrylate compounds, silicone ( meth)acrylate-based compounds, polyester (meth)acrylate-based compounds, linear (meth)acrylic-based compounds, and the like are included. Among these, epoxy (meth)acrylate compounds, urethane (meth)acrylate compounds, and silicone (meth)acrylate compounds can be preferably used. When the resin composition contains an epoxy (meth)acrylate-based compound, a urethane (meth)acrylate-based compound, or a silicone (meth)acrylate-based compound, the strength of the resulting three-dimensional model is likely to increase.

The epoxy (meth)acrylate compound may be a compound containing one or more epoxy groups and (meth)acrylate groups in one molecule, examples of which include bisphenol A type epoxy (meth)acrylate, bisphenol F-type epoxy (meth)acrylate, bisphenyl-type epoxy (meth)acrylate, triphenolmethane-type epoxy (meth)acrylate, cresol novolac-type epoxy (meth)acrylate, phenol novolac-type epoxy (meth)acrylate, and other novolak-type epoxies (Meth)acrylates and the like are included.

A urethane (meth)acrylate compound is obtained by reacting an aliphatic polyisocyanate compound having two isocyanate groups or an aromatic polyisocyanate compound having two isocyanate groups with a (meth)acrylic acid derivative having a hydroxyl group. It can be a compound having a urethane bond and a (meth)acryloyl group.

Examples of isocyanate compounds that are raw materials for the urethane (meth)acrylate compounds include isophorone diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and diphenylmethane-4. ,4′-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, tolidine diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris (isocyanatophenyl)thiophosphate, tetramethylxylylene diisocyanate, 1,6,11-undecane triisocyanate, and the like.

Examples of isocyanate compounds that are raw materials for the urethane (meth)acrylate compounds include ethylene glycol, propylene glycol, glycerin, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, polycaprolactone diol, and the like. Also included are chain-extended isocyanate compounds obtained by reacting polyols with excess isocyanate compounds.

On the other hand, examples of (meth)acrylic acid derivatives having a hydroxyl group, which are raw materials for the above urethane (meth)acrylate compounds, include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxy hydroxyalkyl (meth)acrylates such as butyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate; ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, mono(meth)acrylates of dihydric alcohols such as polyethylene glycol; mono(meth)acrylates and di(meth)acrylates of trihydric alcohols such as trimethylolethane, trimethylolpropane and glycerin; Epoxy (meth)acrylate and the like are included.

The urethane (meth)acrylate compound having the above structure may be commercially available, examples of which include M-1100, M-1200, M-1210, and M-1600 (all manufactured by Toagosei Co., Ltd. ）、ＥＢＥＣＲＹＬ２１０、ＥＢＥＣＲＹＬ２２０、ＥＢＥＣＲＹＬ２３０、ＥＢＥＣＲＹＬ２７０、ＥＢＥＣＲＹＬ１２９０、ＥＢＥＣＲＹＬ２２２０、ＥＢＥＣＲＹＬ４８２７、ＥＢＥＣＲＹＬ４８４２、ＥＢＥＣＲＹＬ４８５８、ＥＢＥＣＲＹＬ５１２９、ＥＢＥＣＲＹＬ６７００、ＥＢＥＣＲＹＬ８４０２、ＥＢＥＣＲＹＬ８８０３、ＥＢＥＣＲＹＬ８８０４、ＥＢＥＣＲＹＬ８８０７、ＥＢＥＣＲＹＬ９２６０（いずれもダイセル・オルネクス社製）、アートレジンＵＮ－３３０、アートResin SH-500B, ArtResin UN-1200TPK, ArtResin UN-1255, ArtResin UN-3320HB, ArtResin UN-7100, ArtResin UN-9000A, ArtResin UN-9000H (all manufactured by Negami Kogyo Co., Ltd.), U -2HA, U-2PHA, U-3HA, U-4HA, U-6H, U-6HA, U-6LPA, U-10H, U-15HA, U-108, U-108A, U-122A, U-122P , U-324A, U-340A, U-340P, U-1084A, U-2061BA, UA-340P, UA-4000, UA-4100, UA-4200, UA-4400, UA-5201P, UA-7100, UA -7200, UA-W2A (both manufactured by Shin-Nakamura Chemical Co., Ltd.), AH-600, AI-600, AT-600, UA-101I, UA-101T, UA-306H, UA-306I, UA-306T (any (manufactured by Kyoeisha Chemical Co., Ltd.), etc.

On the other hand, the urethane (meth)acrylate compound may be a blocked isocyanate obtained by blocking the isocyanate group of polyisocyanate with a blocking agent having a (meth)acrylate group.

The polyisocyanate used to obtain the blocked isocyanate may be the aforementioned "isocyanate compound" or a compound obtained by reacting these compounds with polyols or polyamines. Examples of polyols include conventionally known polyether polyols, polyester polyols, polymer polyols, vegetable oil polyols, and flame-retardant polyols such as phosphorus-containing polyols and halogen-containing polyols. One of these polyols may be contained in the blocked isocyanate, or two or more thereof may be contained.

Examples of the polyether polyols to be reacted with isocyanate and the like include compounds having at least two active hydrogen groups (specifically, polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, and pentaerythritol amines such as ethylenediamine; alkanolamines such as ethanolamine and diethanolamine; etc.) and alkylene oxides (specifically, ethylene oxide, propylene oxide, etc.). Methods for preparing polyether polyols are described, for example, in Gunter Oertel, "Polyurethane Handbook" (1985) Hanser Publishers (Germany), p. 42-53.

Examples of the above polyester polyols include condensation reaction products of polyhydric carboxylic acids such as adipic acid and phthalic acid and polyhydric alcohols such as ethylene glycol, 1,4-butanediol and 1,6-hexanediol, and nylon Wastes from manufacturing, wastes of trimethylolpropane, pentaerythritol, wastes of phthalic acid-based polyester, polyester polyols derived from treated wastes, etc. (See page 117 of the company).

Examples of the above polymer polyols include polymer polyols obtained by reacting the above polyether polyols with ethylenically unsaturated monomers (eg, butadiene, acrylonitrile, styrene, etc.) in the presence of a radical polymerization catalyst. More preferably, the polymer polyol has a molecular weight of about 5,000 to 12,000.

Examples of vegetable oil polyols include hydroxyl group-containing vegetable oils such as castor oil, coconut oil, and the like. Castor oil derivative polyols obtained from castor oil or hydrogenated castor oil can also be suitably used. Examples of castor oil derivative polyols include castor oil polyesters obtained by reaction of castor oil, polyvalent carboxylic acids and short-chain diols, alkylene oxide adducts of castor oils and castor oil polyesters, and the like.

Examples of flame-retardant polyols include phosphorus-containing polyols obtained by adding alkylene oxide to a phosphoric acid compound; halogen-containing polyols obtained by ring-opening polymerization of epichlorohydrin or trichlorobutylene oxide; Aromatic ether polyols obtained by addition of oxides; Aromatic ester polyols obtained by a condensation reaction of a polyhydric carboxylic acid having an aromatic ring and a polyhydric alcohol; and the like.

The hydroxyl value of the polyol to be reacted with isocyanate or the like is preferably 5 to 300 mgKOH/g, more preferably 10 to 250 mgKOH/g. The hydroxyl value can be measured by the method specified in JIS-K0070.

Examples of polyamines to be reacted with isocyanates include ethylenediamine, diethylenetriamine, triethylenetetraamine, hexamethylenepentamine, bisaminopropylpiperazine, tris(2-aminoethyl)amine, isophoronediamine, polyoxyalkylenepolyamine, and diethanolamine. , triethanolamine and the like.

On the other hand, as the blocking agent for blocking the isocyanate groups of the polyisocyanate, any agent may be used as long as it has a (meth)acryloyl group, reacts with the isocyanate group, and can be eliminated by heating.

Specific examples of such blocking agents include t-butylaminoethyl methacrylate (TBAEMA), t-pentylaminoethyl methacrylate (TPAEMA), t-hexylaminoethyl methacrylate (THAEMA), t-butylaminopropyl methacrylate (TPAEMA). ), t-hexylaminoethyl methacrylate (THAEMA), t-butylaminopropyl methacrylate (TBAPMA), and the like.

The blocking reaction of polyisocyanate can generally be carried out at -20 to 150°C, preferably 0 to 100°C. If the temperature is 150°C or lower, side reactions can be prevented, while if the temperature is -20°C or higher, the reaction rate can be controlled within an appropriate range. The blocking reaction between the polyisocyanate compound and the blocking agent can be carried out with or without a solvent. When a solvent is used, it is preferable to use a solvent that is inert to isocyanate groups. A reaction catalyst can be used in the blocking reaction. Examples of specific reaction catalysts include organometallic salts of tin, zinc, lead, etc., metal alcoholates, tertiary amines, and the like.

When the blocked isocyanate prepared as described above is used as the radically polymerizable compound, first, the acryloyl group portion is polymerized by light irradiation. After that, by removing the blocking agent by heating, the generated isocyanate compound can be newly polymerized with polyol, polyamine, etc., and a three-dimensional model containing polyurethane, polyurea, or a mixture thereof can be obtained.

On the other hand, the silicone (meth)acrylate compound can be a compound obtained by adding (meth)acrylic acid to the terminal and/or side chain of silicone having a polysiloxane bond in the main chain. The silicone, which is the raw material for the silicone (meth)acrylate compound, should be an organopolysiloxane polymerized with any combination of known monofunctional, difunctional, trifunctional, or tetrafunctional silane compounds (e.g., alkoxysilane, etc.). can be done. Specific examples of silicone acrylates include commercially available TEGORad2500 (trade name: manufactured by Tego Chemie Service GmbH), and organic compounds having —OH groups such as X-22-4015 (trade name: manufactured by Shin-Etsu Chemical Co., Ltd.). Esterification of modified silicone and acrylic acid in the presence of an acid catalyst; KBM402, KBM403 (trade names: both manufactured by Shin-Etsu Chemical Co., Ltd.) and other organically modified silane compounds such as epoxysilanes are reacted with acrylic acid. etc. are included.

On the other hand, the cationic polymerizable compound, which is another example of the photopolymerizable compound, is not particularly limited as long as it has a group that can be cationic polymerized by irradiation with visible light in the presence of an acid catalyst. Examples thereof include cyclic hetero compounds, and compounds having a cyclic ether group are preferable from the viewpoint of reactivity and the like.

Specific examples of the cationic polymerizable compound include oxirane compounds such as oxirane, methyloxirane, phenyloxirane, and 1,2-diphenyloxirane, or glycidyl ether, glycidyl ester, glycidylamine, and the like wherein the hydrogen atoms of the oxirane rings are methylene bonds. Epoxy group-containing compounds substituted with groups or methine bonding groups; 2-(cyclohexylmethyl)oxirane, 2-ethoxy-3-(cyclohexylmethyl)oxirane, [(cyclohexyloxy)methyl]oxirane, 1,4-bis( Epoxy group-containing compounds having a cycloalkane ring such as oxiranylmethoxymethyl)cyclohexane; 7-oxabicyclo[4.1.0]heptane, 3-methyl-7-oxabicyclo[4.1.0]heptane, 7-Oxabicyclo[4.1.0]heptane-3-ylmethanol, 7-oxabicyclo[4.1.0]heptane-3-methoxymethyl, etc. Alicyclic epoxy group-containing compounds having no aromatic ring Compound; 3-phenyl-7-oxabicyclo[4.1.0]heptane-3-carboxylate, 4-ethylphenyl 7-oxabicyclo[4.1.0]heptane, benzyl 7-oxabicyclo[4.1 .0]heptane-3-carboxylate, 4-ethylphenyl 7-oxabicyclo[4.1.0]heptane-3-carboxylate alicyclic epoxy group-containing compounds having an aromatic ring;
3-ethyl-3-hydroxymethyloxetane, 1,4-bis[(3-ethyl-3-oxetanyl)methoxymethyl]benzene, di(1-ethyl-3-oxetanyl)methyl ether, 3-ethyl-3-( phenoxymethyl)oxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, phenol novolak oxetane, 3-ethyl-{(3-triethoxysilylpropoxy)methyl}oxetane and other oxetanyl group-containing compounds;
2-methyltetrahydrofuran, 2,5-diethoxytetrahydrofuran, tetrahydrofuran-2,2-dimethanol 3-methyl-2,4(3H,5H)-furandione, 2,4-dioxotetrahydrofuran-3-carboxylate, 1,5-di(tetrahydrofuran-2-yl)pentan-3-yl propanoate, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2 - Cyclic ether compounds having a 5-membered ring or more, such as dicarboxylic acid anhydrides and methoxytetrahydropyrans.

The total amount of photopolymerizable compounds contained in the resin composition is preferably 10 to 90% by mass, more preferably 30 to 70% by mass, more preferably 40 to 60% by mass with respect to the total mass of the resin composition. % is more preferred. When the amount of the photopolymerizable compound is within this range, it becomes easier to obtain a three-dimensional object with high strength.

1-2. Thermally polymerizable compound The thermally polymerizable compound contained in the resin composition may be a compound that can be polymerized and cured by heating. A thermally polymerizable compound is usually used in combination with a curing agent, which will be described later.

Examples of such thermally polymerizable compounds include compounds containing at least one group selected from the group consisting of cyclic ether groups, cyanate groups, isocyanate groups, and hydrosilyl groups.

Examples of "compounds having a cyclic ether group" include compounds containing epoxides, oxetanes, tetrahydrofuran, tetrahydropyran, and the like. Among these, compounds having an epoxy group (hereinafter also referred to as "epoxy-based compounds") are preferred from the viewpoint of polymerizability and the like. Examples of epoxy-based compounds include epoxy-based compounds having one or more epoxy groups in the molecule. Examples of epoxy compounds include crystalline epoxy compounds such as biphenyl type epoxy compounds, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, stilbene type epoxy compounds, hydroquinone type epoxy compounds; epoxy compounds, novolak-type epoxy compounds such as naphthol novolac-type epoxy compounds; Polyfunctional epoxy compounds such as phenolmethane-type epoxy compounds, alkyl-modified triphenolmethane-type epoxy compounds, glycidylamine, and tetrafunctional naphthalene-type epoxy compounds; dicyclopentadiene-modified phenol-type epoxy compounds, terpene-modified phenol-type epoxy compounds, silicone-modified modified phenol type epoxy compounds such as epoxy compounds; heterocyclic ring-containing epoxy compounds such as triazine nucleus-containing epoxy compounds; naphthylene ether type epoxies and the like.

Moreover, the "compound having a cyanate group" may be a compound having one or two or more cyanate groups in the molecule. Examples include 1,3- or 1,4-dicyanatobenzene; 1,3,5-tricyanatobenzene; 1,3-, 1,4-, 1,6-, 1,8-, 2, 6-, or 2,7-dicyanatonaphthalene; 1,3,6-tricyanatonaphthalene; 2,2'- or 4,4'-dicyanatobiphenyl; bis(4-cyanatophenyl)methane; 2,2 -bis(4-cyanatophenyl)propane; 2,2-bis(3,5-dichloro-4-cyanatophenyl)propane; 2,2-bis(3-dibromo-4-dicyanatophenyl)propane; (4-cyanatophenyl) ether; bis(4-cyanatophenyl) thioether; bis(4-cyanatophenyl) sulfone; tris(4-cyanatophenyl) phosphite; tris(4-cyanatophenyl) phosphate bis(3-chloro-4-cyanatophenyl)methane: 4-cyanatobiphenyl; 4-cumylcyanatobenzene; 2-t-butyl-1,4-dicyanatobenzene; 2,4-dimethyl-1, 3-dicyanatobenzene; 2,5-di-t-butyl-l,4-dicyanatobenzene; tetramethyl-1,4-dicyanatobenzene; 4-chloro-1,3-dicyanatobenzene; ',5,5'-tetramethyl-4,4'dicyanatodiphenylbis(3-chloro-4-cyanatophenyl)methane: 1,1,1-tris(4-cyanatophenyl)ethane; 1,1 -bis(4-cyanatophenyl)ethane; 2,2-bis(3,5-dichloro-4-cyanatophenyl)propane; 2,2-bis(3,5-dibromo-4-cyanatophenyl)propane bis(p-cyanophenoxyphenoxy)benzene; di(4-cyanatophenyl)ketone; cyanide novolac; cyanide bisphenol polycarbonate oligomers.

"Compound having an isocyanate group" is not particularly limited as long as it is a compound having one or more isocyanate groups in the molecule, examples of which include tolylene diisocyanate, xylylene diisocyanate, naphthylene diisocyanate, diphenylmethane Aromatic diisocyanates such as diisocyanate; alicyclic diisocyanates such as isophorone diisocyanate, dicyclohexylmethane diisocyanate, cyclohexylene diisocyanate, diisocyanatomethylcyclohexane; aliphatic diisocyanates such as hexamethylene diisocyanate; triphenylmethane triisocyanate, tris(isocyanatophenyl) thiophosphate , 1:3 adduct of trimethylolpropane and hexamethylene diisocyanate, trifunctional or higher polyisocyanates such as cyclic trimer of hexamethylene diisocyanate; Blocking agents (e.g., alcohols, phenols, lactams, oximes, acetoacetic acid alkyl esters, malonic acid alkyl esters, phthalimides, imidazoles, hydrogen chloride, hydrogen cyanide, sodium hydrogen sulfite, etc.).

Moreover, the "compound having a hydrosilyl group" may be any compound having one or more hydrosilyl groups in the molecule, and examples thereof include methylhydrosiloxane-dimethylsiloxane copolymers. These "compounds having a hydrosilyl group" are obtained by an addition reaction with a polyorganosiloxane having a vinyl group at its terminal or side chain. Examples of vinyl-containing polysiloxanes include polydimethylsiloxane in which each terminal silicon atom is substituted with a vinyl group, dimethylsiloxane-diphenylsiloxane copolymer in which each terminal silicon atom is substituted with a vinyl group, vinyl Included are group-substituted polyphenylmethylsiloxanes, vinylmethylsiloxane-dimethylsiloxane copolymers having trimethylsilyl groups at each end, and the like.

The total amount of the thermally polymerizable compound and the curing agent described later is preferably 20 to 90% by mass, more preferably 30 to 80% by mass, based on the total amount in the resin composition, and 40 to It is more preferable to contain 60% by mass. When the total amount of the thermally polymerizable compound and the curing agent is within the above range, the dimensional accuracy of the resulting three-dimensional object is likely to increase.

1-3. Visible Light Polymerization Initiator The visible light polymerization initiator is not particularly limited as long as it is a compound that can be excited by visible light to polymerize the photopolymerizable compound. The resin composition may contain only one type of visible light polymerization initiator, or may contain two or more types thereof.

Specific examples of visible light polymerization initiators for radical polymerization include α-diketones (e.g., camphorquinone, 9,10-phenanthrenequinone, 1-phenyl-propane-1,2-dione, diacetyl, 4,4'- hydrogen-abstracting initiators such as aromatic ketones and ketocoumarins; halogen compounds such as tris(trichloromethyl)triazine; organic peroxide initiators such as benzoyl peroxide; hexaaryl Bisimidazole compounds, boron compounds such as cyanine borate, organometallic compound initiators such as bispentadienyl titanium di(pentafluorophenyl); 2-methylthioxanthone, 2,4-diethylthioxanthone, 2,4,6- trimethylbenzoyl and diphenylphosphine oxides, monoacylgermanium compounds and diacylgermanium compounds (e.g. benzoyltrimethylgermanium, dibenzoyldiethylgermanium or bis(4-methoxybenzoyl)-diethylgermanium, etc.), titanocenes (e.g. bis-(η5-2 ,4-cyclopentadien-1-yl)-bis-[2,6-difluoro-3-(1H-pyrrol-1-yl)phenyl]-titanium), N-phenylglycine and the like. Specific examples of visible light polymerization initiators for cationic polymerization include 9,10-dibutoxyanthracene and the like.

Among these, camphorquinone, 9,10-phenanthrenequinone, and the like are preferable from the viewpoint of absorbance in the visible region.

The visible light polymerization initiator preferably has an absorption maximum at a wavelength of 400 nm or more, more preferably in a wavelength range of 420 to 550 nm, and even more preferably in a wavelength range of 450 to 500 nm. When the maximum absorption wavelength of the visible light polymerization initiator is within this range, the wavelength of the visible light irradiated when producing the three-dimensional object can be set to a relatively long wavelength side. Therefore, it is possible to suppress the deterioration of the thermally polymerizable compound and the like during the production of the three-dimensional object.

The visible light polymerization initiator is preferably contained in an amount of 0.025 to 5% by mass, more preferably 0.05 to 1% by mass, and 0.25 to 1% by mass with respect to the total amount in the resin composition. More preferably included. In particular, it is preferably contained in an amount of 0.1 to 3 parts by mass, more preferably 0.5 to 2 parts by mass, based on 100 parts by mass of the photopolymerizable compound. When the visible light polymerization initiator is included in this range, the photocurability of the resin composition tends to be good.

1-4. Ultraviolet light absorber The ultraviolet light absorber is not particularly limited as long as it is a compound capable of absorbing ultraviolet light. In this specification, ultraviolet light is defined as light having a wavelength of less than 400 nm. The ultraviolet light absorbent is preferably a compound capable of absorbing light with a wavelength of 260 to 380 nm, more preferably a compound capable of absorbing light with a wavelength of 300 to 360 nm. In addition, the ultraviolet light absorbent preferably absorbs little light with a wavelength of 400 nm or more, and more preferably does not substantially absorb light with a wavelength of 400 nm or more.

The ultraviolet light absorber may be an organic ultraviolet light absorber or an inorganic ultraviolet light absorber. Moreover, these may be combined. The resin composition may contain only one ultraviolet absorber, or may contain two or more ultraviolet absorbers.

Examples of organic ultraviolet absorbers include thiazolidone-based, benzotriazole-based, acrylonitrile-based, benzophenone-based, aminobutadiene-based, triazine-based, phenyl salicylate-based, and benzoate-based compounds. Among these, triazine-based, benzotriazole-based, and benzophenone-based organic ultraviolet light absorbers are preferable from the viewpoint of sufficiently absorbing ultraviolet light and hardly inhibiting the excitation of the visible light polymerization initiator. .

Examples of thiazolidone-based ultraviolet light absorbers include thiazolidone or derivatives thereof.
Examples of benzotriazole-based ultraviolet light absorbers include 2-(2′-hydroxy-5-methylphenyl)benzotriazole, 2-(2′-hydroxy-3′,5′-di-t-butylphenyl)benzo triazole, 2-(2′-hydroxy-3′-t-butyl-5′-methylphenyl)benzotriazole, 2,2′-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1 ,1,3,3-tetramethylbutyl)phenol] (molecular weight 659; for example LA31 from ADEKA), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenyl ethyl)phenol (molecular weight 447.6; for example Tinuvin 234 from BASF Japan) and the like.
Examples of acrylonitrile ultraviolet absorbers include ethyl 2-cyano-3,3-diphenylacrylate, 2-ethylhexyl 2-cyano-3,3-diphenylacrylate, and the like.

Examples of benzophenone-based ultraviolet light absorbers include 2,4-dihydroxy-benzophenone, 2-hydroxy-4-methoxy-benzophenone, 2-hydroxy-4-n-octoxy-benzophenone, 2-hydroxy-4-dodecyloxy-benzophenone , 2-hydroxy-4-octadecyloxy-benzophenone, 2,2′-dihydroxy-4-methoxy-benzophenone, 2,2′-dihydroxy-4,4′-dimethoxy-benzophenone, 2,2′,4,4 '-Tetrahydroxy-benzophenone and the like are included.
Examples of aminobutadiene-based ultraviolet light absorbers include known aminobutadiene-based ultraviolet light absorbers.

Examples of triazine-based UV absorbers include 2,4-diphenyl-6-(2-hydroxy-4-methoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy -4-ethoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy-4-propoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-(2-hydroxy -4-butoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6- (2-hydroxy-4-hexyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2, 4-diphenyl-6-(2-hydroxy-4-dodecyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-benzyloxyphenyl)-1,3, 5-triazine, [2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyl)oxyphenol] (eg Tinuvin 1577FF manufactured by BASF Japan), [2-[ 4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)phenol] (eg CYASORB UV-1164 manufactured by Cytec Industries, Inc.), etc. be

Examples of phenyl salicylate-based ultraviolet absorbers include phenyl salicylate, 2-4-di-t-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate, and the like.

Examples of benzoate-based ultraviolet light absorbers include 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate (molecular weight 438.7; for example, Sumisorb 400 manufactured by Sumitomo Chemical Co., Ltd.). is included.

Examples of hindered amine ultraviolet absorbers include bis(2,2,6,6-tetramethylpiperidin-4-yl) sebacate and the like.

Among the above, the organic photopolymerization initiator is preferably a compound having a molecular weight of 400 or more. When the molecular weight is 400 or more, it is difficult to volatilize from the resin composition, and it is also difficult to volatilize during heat curing. Therefore, it is possible to improve the light resistance with a relatively small amount.

On the other hand, examples of inorganic ultraviolet absorbers include metal oxide pigments and the like. Specifically, titanium oxide, zirconium oxide, tin oxide, zinc oxide, antimony oxide, or a mixture thereof can be used.

The ultraviolet light absorber is preferably contained in an amount of 0.05 to 5% by mass, more preferably 0.1 to 2% by mass, and more preferably 0.2 to 1% by mass with respect to the total amount in the resin composition. more preferably. When the ultraviolet light absorber is contained in the above range, the light resistance of the resulting three-dimensional object tends to be good.

1-5. Curing Agent The resin composition usually further contains a curing agent and a curing accelerator for curing the thermally polymerizable compound described above. The types of curing agent and curing accelerator are appropriately selected according to the type of the above-described thermally polymerizable compound.

Examples of curing agents and curing accelerators include linear aliphatic diamines having 2 to 20 carbon atoms such as ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, metaphenylenediamine, paraphenylenediamine, paraxylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylpropane, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 4,4'-diaminodicyclohexane, bis(4-aminophenyl) aminos such as phenylmethane, 1,5-diaminonaphthalene, metaxylenediamine, paraxylenediamine, 1,1-bis(4-aminophenyl)cyclohexane, N,N-dimethyl-n-octylamine, dicyanodiamide; aniline Resol-type phenolic resins such as modified resole resins and dimethyl ether resole resins; novolac-type phenolic resins such as phenol novolac resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolac resins; phenylene skeleton-containing phenol aralkyl resins, biphenylene skeleton-containing phenol aralkyl resins Phenolic aralkyl resins such as resins; Phenolic resins having condensed polycyclic structures such as naphthalene skeletons and anthracene skeletons; Polyoxystyrenes such as polyparaoxystyrene; Hexahydrophthalic anhydride (HHPA), Methyltetrahydrophthalic anhydride (MTHPA), etc. Acid anhydrides including aromatic acid anhydrides such as alicyclic acid anhydrides, trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), benzophenonetetracarboxylic acid (BTDA); polysulfides, thioesters, thioethers Polymercaptan compounds such as; isocyanate compounds such as isocyanate prepolymers and blocked isocyanates; organic acids such as carboxylic acid-containing polyester resins; zinc naphthenate, cobalt naphthenate, tin octylate, cobalt octylate, cobalt bisacetylacetonate (II), trisacetylacetonate cobalt (III), and organometallic salts such as zinc acetylacetonate. The resin composition may contain only one type of curing agent or curing accelerator, or may contain two or more types. The amounts of the curing agent and curing accelerator are appropriately selected according to the type and amount of thermal polymerizability.

The amounts of the curing agent and the curing accelerator are appropriately selected according to the amount of the thermally polymerizable compound described above.

1-6. Light Stabilizer The resin composition may contain a light stabilizer. Examples of light stabilizers include photoantioxidants, photoantiaging agents, singlet oxygen quenchers, superoxide anion quenchers, ozone quenchers, infrared absorbers, and the like.

Of these, hindered amine light stabilizers are preferably used, and examples include poly[[6-(N-morpholino)-1,3,5-triazine-2,4-diyl][(2,2,6,6- Tetramethyl-4-piperidyl)imino] hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl)imino] (manufactured by Sumitomo Chemical Co., Ltd., Sumisolv 500), 1,2,3,4-butane Tetra(2,2,6,6-tetramethyl-4-piperidyl) tetracarboxylic acid (manufactured by Adeka Argus), poly[[6-1,1,3,3-tetramethylbutyl)imino-1,3, 5-triazine-2,4-diyl](2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl)imino] ( Tinuvin 944-LD manufactured by Ciba-Geigy), Dimethyl-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine succinate polycondensate (Tinuvin 622LD manufactured by Ciba-Geigy), 2-(3,5-di-t-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentatyl-4-piperidyl) (Ciba-Geigy, Tinuvin) 144), N,N,-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentamethyl-4-piperidyl)amino]-6 -chloro-1,3,5-triazine condensate, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate (manufactured by Sankyo Co., Sanol LS770), bis(N-methyl-2,2, 6,6-tetramethyl-4-piperidyl) sebacate (manufactured by Sankyo Co., Ltd., Sanol LS292), 4-benzoyloxy-2,2,6,6-tetramethyl-4-piperidine (manufactured by Sankyo Co., Ltd., Sanol LS-744) , 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione (manufactured by Sankyo Co., Ltd., Sanol LS-440), 1-[2-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy]-2,2,6,6-tetramethylpiperidine (manufactured by Sankyo Co., Ltd.), 2,2,4,4-tetramethyl-20-(β-lauryl-oxycarbonyl)-ethyl-7-oxa-3, 20 - Diazadeis pio(5,1,11,2) heneicosan-21-one (Sanduvor 305, manufactured by Sand Corporation), [N-(2,2,6,6-tetramethyl-4-piperidyl)-β-alanine] dodecyl ester, Myristyl ester mixture (Sanduvor 3052, manufactured by Sand Corporation), 5-norbornene-2,3-dicarboxylic acid bis(2,2,6,6-tetramethyl-4-piperidyl) ester, 5-norbornene-2,3- Dicarboxylic acid bis(N-methyl-2,2,6,6-tetramethyl-4-piperidyl) ester and the like are included.

The light stabilizer is preferably contained in an amount of 0.05 to 5% by mass relative to the total amount in the resin composition, more preferably 0.1 to 2% by mass, and 0.2 to 1% by mass. is more preferred. When the light stabilizer is contained in the above range, the resulting three-dimensionally shaped article tends to have good light resistance.

1-7. Filler The filler contained in the resin composition is not particularly limited, and may be an organic filler or an inorganic filler. The resin composition may contain only one type of filler, or may contain two or more types.

Conventionally, when a filler is contained in a resin composition for curing by selectively irradiating actinic ray energy, light with a short wavelength such as ultraviolet light is easily scattered, and curability is reduced or obtained. The dimensional accuracy of the three-dimensional object tends to decrease. On the other hand, since the resin composition of the present invention is cured with visible light, such light scattering is less likely to occur even when a relatively large amount of filler is contained. Therefore, the filler amount can be sufficiently increased, and the strength of the three-dimensional object can be increased.

Examples of fillers include glass fillers made of soda lime glass, silicate glass, borosilicate glass, aluminosilicate glass, quartz glass; alumina, zirconium oxide, titanium oxide, lead zirconate titanate, silicon carbide, silicon nitride, nitride Ceramic fillers made of aluminum, tin oxide, etc.; metal fillers made of simple metals such as iron, titanium, gold, silver, copper, tin, lead, bismuth, cobalt, antimony, cadmium, or alloys thereof; graphite, graphene, Carbon filler made of carbon nanotube, etc.; Organic polymer fiber made of polyester, polyamide, polyaramid, polyparaphenylenebenzobisoxazole, polysaccharide, etc.; Potassium titanate whisker, silicone carbide whisker, silicon nitride whisker, α-alumina whisker , zinc oxide whiskers, aluminum borate whiskers, calcium carbonate whiskers, magnesium hydroxide whiskers, basic magnesium sulfate whiskers, calcium silicate whiskers, etc. (including needle-like single crystals of the ceramic filler); Talc, mica, clay, wollastonite, hectorite, saponite, stevensite, hydrite, montmorillonite, nonthrite, bentonite, Na-type tetrasilicic fluoromica, Li-type tetrasilicic fluoromica, Na-type fluorine teniolite, Li-type fluorine Swellable mica such as teniolite and clay minerals such as vermicularite are included. Furthermore, examples of fillers include polyolefin fillers made of polyethylene, polypropylene, etc.; FEP (tetrafluoroethylene-hexafluoropropylene copolymer), PFA (tetrafluoroethylene-perfluoroalkoxyethylene copolymer), Fluororesin fillers such as ETFE (tetrafluoroethylene-ethylene copolymer) are also included.

Among the above, organic polymer fibers are preferable, and nanofibers made of polysaccharides are particularly preferable. Examples of polysaccharides include cellulose, hemicellulose, lignocellulose, chitin, chitosan, and the like. Among these, cellulose and chitin are preferred, and cellulose is more preferred, from the viewpoint of further increasing the strength of the three-dimensionally shaped article to be obtained.

A fibrous filler made of cellulose, that is, cellulose nanofiber (hereinafter also simply referred to as “nanocellulose”) is produced by mechanical fibrillation of plant-derived fibers or plant cell walls, biosynthesis by acetic acid bacteria, 2, It may be cellulose nanofibers mainly composed of fibrous nanofibrils obtained by oxidation with N-oxyl compounds such as 2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) or electrospinning. . Nanocellulose is a cellulose whose main component is whisker-like (needle-like) crystallized nanofibrils obtained by mechanically fibrillating plant-derived fibers or plant cell walls and then subjecting them to acid treatment. It may be nanocrystals or other shapes. Nanocellulose may contain cellulose as a main component, and may contain lignin, hemicellulose, and the like. Nanocellulose containing hydrophobic lignin without delignification treatment is preferable because it has a high affinity with photopolymerizable compounds and thermally polymerizable compounds.

The shape of the filler is not particularly limited, and may be, for example, fibrous (including whisker-like) or particulate. is preferred.

When the filler is particulate, its average particle size is preferably 0.005 to 200 μm, more preferably 0.01 to 100 μm, even more preferably 0.1 to 50 μm. When the average particle size of the particulate filler is 0.1 μm or more, the strength of the three-dimensionally shaped article tends to increase. On the other hand, when the average particle size is 50 µm or less, it becomes easier to form a three-dimensional object with high definition. The average particle diameter can be measured by analyzing an image obtained by imaging the resin composition with a transmission electron microscope (TEM).

On the other hand, when the filler is fibrous, the average fiber diameter is preferably 0.002 μm or more and 20 μm or less. When the average fiber diameter is 0.002 μm or more, the strength of the three-dimensional object is likely to increase. When the average fiber diameter is 20 μm or less, the filler does not excessively increase the viscosity of the resin composition, and the accuracy of the three-dimensionally shaped article tends to be good. The average fiber diameter of the filler is more preferably 0.005 μm or more and 10 μm or less, further preferably 0.01 μm or more and 8 μm or less, and particularly preferably 0.02 μm or more and 5 μm or less.

The average fiber length of the filler is preferably 0.2 μm or more and 200 μm or less. When the average fiber length is 0.2 μm or more, the strength of the three-dimensional object is likely to increase. When the average fiber length is 100 μm or less, sedimentation of the filler due to entanglement of the filler with each other is unlikely to occur. The average fiber length of the filler is more preferably 0.5 μm or more and 100 μm or less, further preferably 1 μm or more and 60 μm or less, and particularly preferably 1 μm or more and 40 μm or less.

The aspect ratio of the filler is preferably 10 or more and 10,000 or less. When the aspect ratio is 10 or more, the strength of the three-dimensional object tends to be higher. If the aspect ratio is 10,000 or less, the fillers are less likely to sediment due to entanglement of the fillers. The aspect ratio of the filler is more preferably 12 or more and 8000 or less, further preferably 15 or more and 2000 or less, and particularly preferably 18 or more and 800 or less.

The average fiber diameter, average fiber length and aspect ratio of the filler can be measured by analyzing an image obtained by photographing the resin composition with a transmission electron microscope (TEM).

Here, the amount of filler contained in the resin composition is preferably 1 to 50% by mass, more preferably 5 to 40% by mass, relative to the total mass of the resin composition. When the amount of the filler is within this range, it becomes easier to obtain a three-dimensionally shaped article with high strength.

Here, the filler may be surface-treated with various surface-treating agents such as known silane coupling agents. When the filler is surface-treated, the adhesion between the filler and the photopolymerizable compound or thermally polymerizable compound is enhanced, making it easier to obtain a three-dimensional object with higher strength.

1-8. Other Components The resin composition contains a photosensitizer, a polymerization inhibitor, a photosensitizer, a polymerization inhibitor, a Optional additives such as antioxidants, colorants such as dyes and pigments, defoamers and surfactants may also be included.

1-9. Physical Properties of Resin Composition The resin composition of the present invention has a viscosity of 0.2 to 100 Pa s at 25° C., measured using a rotational viscometer in accordance with JIS K-7117-1. is preferred, and 1 to 10 Pa·s is more preferred. When the viscosity of the resin composition is within this range, appropriate fluidity can be obtained in the method for producing a three-dimensional object described below. As a result, it is possible to improve the modeling speed, and it becomes difficult for the filler and the like to settle in the resin composition, and thus the strength of the three-dimensional model can be easily increased.

1-10. Preparation method of resin composition The resin composition contains the photopolymerizable compound, the thermally polymerizable compound, the visible light polymerization initiator, the ultraviolet light absorber, and, if necessary, a filler, a curing agent, a light stabilizer, and the like. It can be prepared by mixing in any order.

A known device can be used for mixing the resin composition. For example, Ultra Turrax (manufactured by IKA Japan), TK Homomixer (manufactured by Primix), TK Pipeline Homomixer (manufactured by Primix), TK Filmix (manufactured by Primix), Clearmix (manufactured by M Technic), Clea SS5 (manufactured by M Technic Co., Ltd.), Cavitron (manufactured by Eurotech Co., Ltd.), Medialess stirrer such as Fine Flow Mill (manufactured by Taiheiyo Kiko Co., Ltd.), Visco Mill (manufactured by Aimex), Apex Mill (manufactured by Kotobuki Kogyo Co., Ltd.), Star Mill (Ashizawa, manufactured by Fine Tech), DCP Super Flow (manufactured by Nihon Eirich Co., Ltd.), MP Mill (manufactured by Inoue Seisakusho), Spike Mill (manufactured by Inoue Seisakusho), Mighty Mill (manufactured by Inoue Seisakusho), SC Mill (Mitsui Mining Co., Ltd.) and other media agitators, Ultimizer (Sugino Machine Co., Ltd.), Starburst (Sugino Machine Co., Ltd.), Nanomizer (Yoshida Kikai Co., Ltd.), NANO 3000 (Miryu Co., Ltd.), etc. apparatus.

In addition, a rotation and revolution mixer such as Awatori Mixer (manufactured by Thinky) and Kakuhunter (manufactured by Shashin Kagaku), planetary mixers such as Hivis Mix (manufactured by Primix) and Hivis Disper (manufactured by Primix), Nanoruptor (manufactured by Sonic Bio), etc., can also be suitably used.

2. Method for producing a three-dimensional object The liquid resin composition described above includes a step of selectively irradiating visible light to form a primary cured product containing a cured product of the photopolymerizable compound. It can be used in manufacturing methods.

In the method for producing a three-dimensional object using the above-described resin composition, first, the resin composition is selectively irradiated with visible light, and the above-described photopolymerizable compound is cured into a desired shape to form a primary cured product. Perform the stereolithography process. After forming the primary cured product, a thermosetting step is performed to thermally polymerize the thermopolymerizable compound contained in the primary cured product to obtain a three-dimensional object. In addition, after producing the primary cured product, a visible light irradiation step of further irradiating visible light may be performed.

Examples of such a three-dimensional object manufacturing method include the following two embodiments, but the method of the present invention is not limited to these methods.

2-1. Additive manufacturing method (SLA method)
FIG. 1 is a schematic diagram showing an example of an apparatus (apparatus for producing a three-dimensional object) for producing a primary cured product by the layered manufacturing method. The manufacturing apparatus 500 supports a modeling tank 510 capable of storing a liquid resin composition 550, a modeling stage 520 capable of reciprocating in the vertical direction (depth direction) inside the modeling tank 510, and the modeling stage 520. It has a base 521 , a visible light source 530 , a galvanomirror 531 for guiding the visible light into the modeling tank 510 , and the like.

The modeling bath 510 may have a size capable of accommodating the primary cured product to be manufactured. Also, a known light source can be used for the light source 530 for irradiating visible light. Examples of light sources for emitting visible light include metal halide lamps, halogen lamps, xenon lamps, LEDs, sunlight, ultra-high pressure mercury lamps, and the like. Among these light sources, LEDs are particularly preferable because any wavelength can be selected. Since light sources other than LEDs contain ultraviolet light, it is preferable to remove the ultraviolet light through a filter. The wavelength of visible light for irradiation is preferably 400 to 550 nm, more preferably 420 to 500 nm.

In this method, first, the modeling tank 510 is filled with the resin composition 550 . At this time, the modeling stage 520 is arranged below the liquid surface of the resin composition 550 by the thickness of the modeled article layer (first modeled article layer) to be produced. In this state, the visible light emitted from the light source 530 is guided by the galvanomirror 531 or the like, scanned, and irradiated to the resin composition 550 on the modeling stage 520 . At this time, by selectively irradiating only the region where the first modeled object layer is to be formed with visible light, the first modeled object layer is formed in a desired shape.

After that, the modeling stage 520 is lowered (moved in the depth direction) by the thickness of one layer (the thickness of the second modeled article layer to be produced next), and the first modeled article layer is immersed in the resin composition 550. subside. As a result, the resin composition is supplied onto the first modeled article layer. Subsequently, in the same manner as described above, the visible light emitted from the light source 530 is guided by the galvanomirror 531 or the like, and irradiated to the resin composition 550 located above the first model layer. Also at this time, the visible light is selectively irradiated only to the region where the second modeled object layer is to be formed. As a result, the second modeled object layer is laminated on the above-described first modeled object layer.

After that, by repeating the lowering of the modeling stage 520 (the supply of the resin composition) and the irradiation of visible light, the primary cured product is formed in a desired shape. Note that the shape of the primary cured product produced by the above method is the same as the shape of the three-dimensional object to be finally produced.

The obtained primary cured product may be further irradiated with visible light, if necessary. Visible light irradiation may be performed only on a desired range, or may be performed on the entire primary cured product. When such visible light irradiation is performed, the polymerizability is enhanced to the inside of the primary cured product, and warping of the obtained three-dimensional molded product can be easily suppressed. The reason why warping is suppressed by curing to the inside is that the thermosetting component in the primary cured product is in an uncured state, and cure shrinkage occurs during the process of polymerization by heating. At this time, if the primary cured product receives shrinkage stress at a high temperature, it is likely to warp. Therefore, by further irradiating the primary cured product with visible light to increase the degree of polymerization inside, the strength of the primary cured product increases and deformation due to curing shrinkage of the thermosetting component can be reduced, so warping is suppressed. .

Thereafter, the thermally polymerizable compound contained in the primary cured product is heated and cured by a known method. When heating the primary cured product, the temperature is preferably such that the primary cured product is not deformed. For example, the temperature is preferably lower than the glass transition temperature (Tg) of the cured product of the photopolymerizable compound.

2-2. Continuous modeling method (CLIP method)
FIG. 2 is a schematic diagram showing an example of an apparatus (apparatus for producing a three-dimensional object) for producing a primary cured product by the continuous modeling method. As shown in FIG. 2, the manufacturing apparatus 600 includes a modeling tank 610 capable of storing a liquid resin composition, a modeling stage 620 capable of reciprocating in the vertical direction (depth direction), and a visible light irradiation stage. and a light source 660 and the like. The modeling tank 610 has a window portion 615 at its bottom which does not allow the resin composition to pass through but allows visible light and oxygen to pass through. The material of the modeling bath 610 is not particularly limited as long as it has a wider width than the three-dimensional object to be manufactured and does not interact with the resin composition. Also, the material of the window portion 615 is not particularly limited as long as it does not impair the purpose and curing of the present embodiment.

Also, a known light source 660 for emitting visible light can be used, and the same light source as used in the layered manufacturing method can be used. In addition, by using an SLM projection optical system having a spatial light modulator (SLM) such as a liquid crystal panel or a digital mirror device (DMD) as the light source 660, visible light can be projected onto a desired region. good. In the CLIP method, a light source that can irradiate light with a wavelength of 420 to 550 nm is particularly preferable, and a light source that can irradiate light with a wavelength of 440 to 500 nm is more preferable.

In this method, first, the modeling tank 610 is filled with the resin composition described above. Then, oxygen is introduced into the bottom side of the modeling bath 610 through a window 615 provided at the bottom of the modeling bath 610 . The method of introducing oxygen is not particularly limited, and for example, a method of creating an atmosphere with a high oxygen concentration outside the modeling tank 610 and applying pressure to the atmosphere can be used.

By supplying oxygen into the modeling tank 610 through the window 615 in this manner, the oxygen concentration increases in the region on the window 615 side, and the buffer region 642 where the photopolymerizable compound is not cured even when irradiated with visible light. is formed. On the other hand, the region above the buffer region 642 has a sufficiently lower oxygen concentration than the buffer region 642 and becomes a curing region 644 in which the photopolymerizable compound can be cured by visible light irradiation.

Subsequently, a step of selectively irradiating visible light from the buffer region side 642 to form a cured product of the photopolymerizable compound in the curing region 644 is performed. Specifically, a modeling stage 620 serving as a starting point for producing the primary cured product is arranged near the interface between the curing region 644 and the buffer region 642 . Then, the light source 660 arranged on the buffer area 642 side selectively irradiates the bottom surface side of the modeling stage 620 with visible light. As a result, the photopolymerizable compound near the bottom surface (curing region 644) of the modeling stage 620 is cured to form the uppermost portion of the primary cured product.

After that, the modeling stage 620 is raised (moved away from the buffer area 642). As a result, the uncured resin composition is newly supplied to the curing region 644 on the bottom side of the modeling tank 610 from the cured product 651 . Then, while the modeling stage 620 and the cured product 651 are continuously raised, visible light is continuously and selectively irradiated (areas to be cured) from the light source 660 . As a result, the cured product is continuously formed from the bottom surface of the modeling stage 620 to the bottom side of the modeling tank 610, and a seamless primary modeled product with high strength is manufactured. Also in this embodiment, the shape of the primary cured product is the same as the shape of the three-dimensional object to be finally produced.

After that, the obtained primary cured product may be further irradiated with visible light, if necessary. Visible light irradiation may be performed only on a desired range, or may be performed on the entire primary cured product. As described above, when such visible light irradiation is performed, the polymerizability of the photopolymerizable compound inside the primary cured product is enhanced, and warpage of the obtained three-dimensional object is easily suppressed.

Thereafter, the thermally polymerizable compound contained in the primary cured product is heated and cured by a known method. When heating the primary cured product, the temperature is preferably such that the primary cured product is not deformed. For example, the temperature is preferably lower than the glass transition temperature (Tg) of the cured product of the photopolymerizable compound.

In the CLIP method described above, if the viscosity of the resin composition is high, it is difficult to fill the hardening region 644 of the modeling tank 610 with a new resin composition. Therefore, it is difficult to lift the formed cured product 651, and if the cured product 651 is forcibly lifted, the resin composition is not uniformly filled in the curing region 644, and the strength of the obtained three-dimensional object is sometimes lowered. On the other hand, it is considered that increasing the thickness of the buffer region 642 makes it easier for the hardening region 644 to be filled with a new resin composition. However, conventional short-wavelength light, such as ultraviolet light, cannot sufficiently reach the hardening region 644 when the thickness of the buffer region 642 increases, and conventionally, the thickness of the buffer region 642 could not be increased.

On the other hand, since visible light has a long wavelength, it easily reaches the hardening region 644 even if the thickness of the buffer region 642 is large. Therefore, according to the manufacturing method of the present invention, it is possible to increase the thickness of the buffer region 642, and it is possible to manufacture a three-dimensional object with high strength.

Specific examples of the present invention are described below. The scope of the present invention should not be construed as being limited by these examples.

1. Materials The following materials were prepared for the preparation of resin compositions in Examples and Comparative Examples.
(Photopolymerizable compound)
Acrylate-based compounds: trimethylpropane triacrylate and diacrylate (CN120Z manufactured by Sartomer)
- Silicone acrylate compound: (UV RCA 170, manufactured by Bluestar Silicones)

(Thermal polymerizable compound)
Epoxy compound: poly[2-(chloromethyl)oxirane-alt-4,4′-(propane-2,2-diyl)diphenol] (Araldite 506 manufactured by Huntsman), and its curing agent (4,4 '-methylenebis(2,6-dimethylaniline)
- Silicone compound: one-component addition-curable silicone (KE-1056, manufactured by Shin-Etsu Chemical Co., Ltd.), and its curing agent (N,N-dimethyloctylamine)
・Urethane compound: isophorone diisocyanate and its curing agent (polytetramethylene oxide)
Cyanate ester compound: 1-bis (4-cyanatophenyl) ethane, and its curing agent (isobornyl acrylate solution containing 1500 ppm of zinc (II) acetylacetonate monohydrate and 2-(5-chloro -2-benzotriazolyl)-6-tert-butyl-p-cresol)

(Visible light polymerization initiator)
・Camphorquinone (manufactured by Tokyo Chemical Industry Co., Ltd., maximum absorption 470 nm)
・ 3-Ketocoumarin (manufactured by Tokyo Chemical Industry Co., Ltd., maximum absorption 460 nm)

(Ultraviolet photopolymerization initiator)
- Alkylphenone-based photopolymerization initiator (manufactured by BASF, IRGACURE184, maximum absorption 330 nm)

(Ultraviolet light absorber)
- Benzophenone-based ultraviolet light absorber: Adekastab 1413 manufactured by ADEKA
- Benzotriazole-based ultraviolet light absorber: Adekastab LA-32 manufactured by ADEKA
・ Triazine-based ultraviolet light absorber: ADEKA Co., Ltd., Adekastab LA-46
- Benzoate-based ultraviolet light absorber: Sumisolv 400 manufactured by Sumitomo Chemical Co., Ltd.

(light stabilizer)
- Hindered amine light stabilizer: Sumisolv 500 manufactured by Sumitomo Chemical Co., Ltd.

(filler)
・Magnesium sulfate whisker: MOS-HIGE manufactured by Ube Materials Co., Ltd. ・Cellulose nanofiber: BiNFis manufactured by Sugino Machine Co., Ltd.

2. Preparation of resin composition (Examples 1-9 and Comparative Examples 1-5)
Each component was mixed in the materials and mass ratios shown in Table 1 below to obtain a resin composition. Mixing was performed for 5 minutes at a revolution speed of 60 rpm and a rotation speed of 180 rpm using a planetary kneader (Hibismix 2P-1 manufactured by Primix).

3. Production of Three-Dimensional Shaped Object Using the resin compositions described above, three-dimensionally shaped objects were produced by the methods shown below.

(Comparative Examples 1-5, Examples 1-3)
The resin compositions prepared above were put into the modeling tank 510 of the three-dimensional model manufacturing apparatus having the configuration shown in FIG. Then, for Comparative Examples 1 to 5, a laser diode (NDU4116 manufactured by Nichia Corporation) with a wavelength of 370 nm and an output of 70 mW was used as the light source 530, and for Examples 1 to 3, a wavelength of 460 nm and an output of 100 mW was used as the light source 530. Using a laser diode (NDB4216 manufactured by Nichia Corporation), the irradiation of light and the descent of the modeling stage 520 are repeated to obtain a primary cured product of JIS K7161-2 (ISO 527-2) 1A type test piece shape. Obtained. A primary cured product in which the longitudinal direction of the tensile test piece is the molding direction (the descending direction of the stage) and a primary cured product in which the longitudinal direction of the tensile test piece is parallel to the molding direction were prepared. The resulting primary cured product was washed with isopropyl alcohol.
For Comparative Examples 1 and 4, the primary cured product was directly used as a three-dimensional object.
On the other hand, the primary cured products of Comparative Examples 2, 3, and 5 and Examples 1 and 2 were thermally cured under the conditions shown in Table 1 below.
In addition, for the primary cured product of Example 3, light with a wavelength of 400 to 700 nm was irradiated from a xenon lamp on both sides of the three-dimensional object (test piece) for 5 minutes each at an irradiation intensity of 5 mW/cm ² . did. Then, it was heat-cured under the conditions shown in Table 1 below.

(Examples 4-9)
A resin composition was put into the modeling tank 610 of the manufacturing apparatus 600 shown in FIG. 2 to produce the three-dimensional model. A 0.0025 inch thick Teflon® AF2400 film (window 615) manufactured by Biogeneral, which is permeable to oxygen, a polymerization inhibitor, is placed at the bottom of the build tank 610 . Then, the atmosphere outside the modeling tank 610 was set to an oxygen atmosphere, and then moderate pressurization was performed. As a result, a buffer region 642 containing the resin composition and oxygen was formed on the bottom side of the modeling bath 610, and a curing region 644 having a lower oxygen concentration than the buffer region was formed above the buffer region 642.
Then, the modeling stage 620 was raised while a visible light source 660: a DLP projector (HD 142X manufactured by Optoma) was used to planarly irradiate light. At this time, the irradiation intensity of visible light was set to 5 mW/cm ² . Also, the lifting speed of the modeling stage 620 was set to 50 mm/hr. Then, a three-dimensional model was produced so as to have a test piece shape of JIS K7161-2 (ISO 527-2) 1A type. By this method, the primary cured product in which the longitudinal direction of the tensile test piece is horizontal and the modeling direction (lifting direction of the modeling stage 620), and the primary cured product in which the longitudinal direction of the tensile test piece is horizontal to the modeling direction were made respectively. The three-dimensional object obtained was washed with isopropyl alcohol.
The primary cured products of Examples 4, 5, and 7 to 9 were thermally cured under the conditions shown in Table 1 below.
On the other hand, for the primary cured product of Example 6, light with a wavelength of 400 to 700 nm was irradiated from a xenon lamp on both sides of the three-dimensional object (test piece) for 5 minutes each at an irradiation intensity of 5 mW/cm ² . did. Then, it was heat-cured under the conditions shown in Table 1 below.

4. Evaluation The three-dimensional molded article obtained was evaluated by the following methods. Table 2 shows the results obtained.

(Strength)
The tensile strength was evaluated by a tensile test according to JIS K7161-1 for each three-dimensional object whose longitudinal direction was the molding direction and the three-dimensional object whose longitudinal direction was parallel to the molding direction. At this time, the distance between the grips was 115 mm, and the test speed was 5 mm/min. Also, the value obtained by dividing the stress at break by the cross-sectional area of the test piece was calculated as each tensile strength.

A three-dimensional object whose longitudinal direction is parallel to the forming direction was evaluated according to the following criteria.
◎: Horizontal tensile strength is 100 MPa or more ○: Horizontal tensile strength is 20 MPa or more and less than 100 MPa ×: Horizontal tensile strength is less than 20 MPa

The three-dimensional object whose longitudinal direction is the molding direction was evaluated by the following molding strength ratio.
Strength ratio in the building direction = tensile strength in the building direction / tensile strength in the direction horizontal to the building direction ◎: strength ratio in the building direction is 0.9 or more ○: strength ratio in the building direction is 0.6 or more and less than 0.9 ×: strength in the building direction ratio less than 0.6

(warp)
The above three-dimensional object (longitudinal direction is horizontal to the molding direction) was placed on a metal surface plate and scanned in the thickness direction using a laser displacement meter (LK-G5000 manufactured by Keyence Corporation). Then, the amount of warpage of the three-dimensional molded article was calculated as follows.
Amount of warpage = Maximum height of test piece - Minimum height of test piece

◎: Less than 0.5 mm ○: 0.5 mm or more and less than 2 mm ×: 2 mm or more

(light resistance)
A 7.5 kW super xenon weather meter SX75 manufactured by Suga Test Instruments Co., Ltd. was used to perform a light resistance test in accordance with JIS D0205 on the three-dimensional object (longitudinal direction is horizontal to the forming direction). The light fastness test was performed using a xenon arc lamp under the environment of a black panel temperature of 60° C. and a relative humidity of 50%. Further, light with a wavelength range of 300 to 400 nm was irradiated for 300 hours through an outer glass filter of silicate glass and an inner filter of quartz glass so that the sample surface radiation intensity was 75 W/m ² . After that, the strength retention after the light resistance test was calculated and evaluated as follows.
Strength retention rate = Tensile strength after light resistance test/Tensile strength before light resistance test ◎: Strength retention rate is 0.9 or more ○: Strength retention rate is 0.8 or more and less than 0.9 △: Strength retention rate is 0 .6 or more and less than 0.8 ×: Strength retention rate is 0.4 or more and less than 0.6 XX: Strength retention rate is less than 0.4

As shown in Table 2 above, when the thermopolymerizable resin was not contained, the obtained three-dimensional object was likely to warp (Comparative Examples 1 and 4). In addition, when the thermopolymerizable resin was included and the ultraviolet absorber was not included (Comparative Examples 2 and 5), the light resistance tended to be low. In particular, in Comparative Example 2, which was cured with ultraviolet light, the evaluation of warpage was also low. It is considered that this is because the effect of adding the thermally polymerizable compound was not obtained because the material was deteriorated by the light during the preparation of the primary cured material. On the other hand, when a resin composition containing an ultraviolet light absorber was cured with ultraviolet light, it could not be sufficiently cured and the strength was very low (Comparative Example 3).

In contrast, the resin composition containing a photopolymerizable compound, a thermally polymerizable compound, a visible light polymerization initiator, and an ultraviolet light absorber had high light resistance and high strength both in the horizontal direction and the modeling direction. It is inferred that even if an ultraviolet light absorber was contained, the curing was hardly inhibited and the strength was high (Examples 1 to 9) because the curing was performed with visible light. In addition, since these examples contained a thermally polymerizable compound, warping was less likely to occur.

In particular, when the light irradiation step was further included after the production of the primary cured product, the cured product was less likely to warp (Examples 3 and 6). On the other hand, when the filler was contained, the strength of the obtained three-dimensional molded article was likely to increase (Examples 2 and 7). Furthermore, when a light stabilizer was included, the light resistance was particularly likely to increase (Example 5). As a three-dimensional modeling method, the strength in the modeling direction was higher in the CLIP method than in the SLA method. In the CLIP method, since a three-dimensional object is produced seamlessly, it is considered that the strength in the forming direction is increased.

This application claims priority based on Japanese Patent Application No. 2018-036684 filed on March 1, 2018. All contents described in the specification and drawings are incorporated herein by reference.

According to the resin composition of the present invention, it is possible to provide a shaped article with little warpage, high strength, and good light resistance. Therefore, the present invention is expected to expand the range of applications of three-dimensional objects using resin compositions and contribute to the development and spread of technology in the same field.

500, 600 manufacturing apparatus 510, 610 modeling tank 615 window 520, 620 modeling stage 521 base 530, 660 light source 531 galvanomirror 550 resin composition 642 buffer region 644 curing region 651 cured product

Claims (9)

A resin composition for use in a method for producing a three-dimensional object made of a cured product of the resin composition by selectively irradiating a liquid resin composition with visible light,
30 to 60% by mass of a photopolymerizable compound,
a thermally polymerizable compound;
0.025 to 5% by mass of a visible light polymerization initiator having an absorption maximum in a wavelength region of 400 nm or more;
0.2 to 5% by mass of an ultraviolet light absorber,
a curing agent;
including
The total amount of the thermally polymerizable compound and the curing agent is 30 to 60 % by mass,
Resin composition. The photopolymerizable compound and/or the thermally polymerizable compound contains in the molecule at least one structure selected from the group consisting of an aromatic ring, a triazine ring, an ester bond, a urethane bond, and a urea bond,
The resin composition according to claim 1. further comprising a light stabilizer;
The resin composition according to claim 1 or 2. further comprising a filler;
The resin composition according to any one of claims 1 to 3. A stereolithography step of selectively irradiating the resin composition according to any one of claims 1 to 4 with visible light to form a primary cured product containing a cured product of the photopolymerizable compound,
A method for manufacturing a three-dimensional object. Including a thermosetting step of further thermosetting the primary cured product,
The manufacturing method of the three-dimensional molded article according to claim 5. Including a light irradiation step of further irradiating the primary cured product with visible light before the heat curing step,
The manufacturing method of the three-dimensional molded article according to claim 6. The stereolithography step is
a buffer region containing the resin composition and oxygen, wherein the oxygen inhibits curing of the photopolymerizable compound; and a buffer region containing at least the resin composition, having a lower oxygen concentration than the buffer region, and curing the photopolymerizable compound. a first step of forming a curing region adjacent to and within the model vat;
a second step of selectively irradiating the resin composition with visible light from the buffer region side to cure the photopolymerizable compound in the curing region;
including
In the second step, while moving the formed cured product to the side opposite to the buffer region, the curing region is continuously irradiated with visible light to form the primary cured product.
A method for producing a three-dimensional object according to any one of claims 5 to 7. A three-dimensional object, which is a cured product of the resin composition according to any one of claims 1 to 4.

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