JPH10279819A - Optical stereolithographic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical stereolithographic resin composition which can give a high-quality stereolithographic product having a high heat distortion temperature, a high bending modulus, high heat resistance, high rigidity and a coefficient of thermal expansion low enough to inhibit dimensional change with changing temperature and to provide a stereolithographic product made therefrom. SOLUTION: This composition comprises a liquid photocurable resin, 5-65 vol.%, based on the total volume of the composition, aluminum microparticles having a mean particle diameter of 3-70 μm and 5-30 vol.%, based on the total volume of the composition, whiskers having a diameter of 0.3-1 μm, a length of 10-70 μm and an aspect ratio of 10-100 (the total content of the aluminum oxide microparticles and the whiskers is 10-70 vol.%). The stereolithographic product is obtained by using this composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical three-dimensional modeling resin composition, a method for producing an optical three-dimensional modeling product using the optical three-dimensional modeling resin composition, and the optical three-dimensional modeling resin composition. The present invention relates to an optical three-dimensional object obtained by using the method. More specifically, the present invention has an extremely high heat distortion temperature and extremely high flexural modulus, and has an unprecedented high heat resistance,
High rigidity, low dimensional shrinkage during photo-curing, excellent dimensional accuracy, and extremely low linear thermal expansion coefficient. TECHNICAL FIELD The present invention relates to a resin composition for optical three-dimensional modeling capable of obtaining a three-dimensional molded article, a method for producing an optical three-dimensional molded article using the same, and an optical three-dimensional molded article obtained thereby.

[0002]

2. Description of the Related Art In general, liquid photocurable resin compositions are widely used as coatings (especially hard coating agents), photoresists, dental materials, and the like.
A method of three-dimensionally optically molding the photocurable resin composition based on the data input to D has attracted particular attention. Regarding the optical three-dimensional molding technology, a required amount of controlled light energy is supplied to a liquid photo-curable resin to cure it into a thin layer, and then a liquid photo-curable resin is further supplied thereon, and then the light is controlled. Japanese Patent Application Laid-Open No. 56-144478 discloses an optical three-dimensional modeling method for producing a three-dimensional molded product by repeating a process of irradiating and laminating and hardening into a thin layer, and further discloses a basic practical method. Showa 60-
247515. After that, a number of proposals regarding optical three-dimensional modeling technology have been made, for example, JP-A-62-35966, JP-A-1-204915, JP-A-2-113925, and JP-A-2-145616. Gazette, JP-A-2-153
722, JP-A-3-15520, JP-A-3-15520
Japanese Patent Application Laid-Open No. 21432 and Japanese Patent Application Laid-Open No. 3-41126 disclose techniques relating to an optical three-dimensional printing method.

[0003] A typical method for optically producing a three-dimensional object is a computer controlled ultraviolet ray so as to obtain a desired pattern on the liquid surface of a liquid photocurable resin composition placed in a container. A laser is selectively irradiated to cure to a predetermined thickness, and then one layer of the liquid resin composition is supplied on the cured layer and similarly irradiated with an ultraviolet laser to be cured as described above. A method of manufacturing a three-dimensional structure having a final shape by repeating a laminating operation of forming a continuous cured layer by using the same is generally used widely. In this method, even if the shape of the modeled object is considerably complicated, the target three-dimensional modeled object can be manufactured easily and in a relatively short time, and thus, it has been receiving particular attention in recent years.

Photocurable resin compositions used for coatings, photoresists, dental materials and the like include unsaturated polyesters, epoxy (meth) acrylates, urethane (meth) acrylates, (meth) acrylate monomers and the like. The addition of a photopolymerization initiator to a hydrophilic resin is widely used. The photocurable resin composition used in the optical three-dimensional molding method includes a photopolymerizable modified (poly) urethane (meth) acrylate compound, an oligoester acrylate compound, an epoxy acrylate compound, an epoxy compound, and a polyimide. Compounds, one or more of photopolymerizable compounds such as aminoalkyd compounds, vinyl ether compounds, etc. as a main component, and a photopolymerization initiator added thereto, and recently,
JP-A-1-204915, JP-A-1-21330
4, JP-A-2-28261, JP-A-2-7
Various improved techniques are disclosed in JP-A-5617, JP-A-2-145616, JP-A-3-104626, JP-A-3-114732, JP-A-3-1147324, and the like.

[0005] The photocurable resin composition used in the optical three-dimensional molding method must be a low-viscosity liquid material and have a small volume shrinkage during curing from the viewpoints of handleability, molding speed, and molding accuracy. It is required that a three-dimensional structure obtained by photocuring has good mechanical properties. In recent years, the demand and use of optical three-dimensional objects have tended to expand, and depending on the application, in addition to the above-described various properties, it has a high heat deformation temperature, is excellent in heat resistance, and is high in quality. There has been a demand for a three-dimensional structure having rigidity, a small coefficient of thermal expansion, a small dimensional change even when the temperature changes, and an excellent thermal dimensional stability. For example,
Optical three-dimensional objects used in the design of complex heat transfer circuits,
For optical three-dimensional objects used for analyzing the heat medium behavior of complex structures, those that have small volume shrinkage during light curing, high heat deformation temperature, rigidity, and thermal dimensional stability are required. Have been.

Conventionally, a method of introducing a benzene ring into the molecule of a photocurable resin, a method of increasing the crosslink density in a photocurable material, and the like, with the aim of obtaining an optical three-dimensional structure having improved heat resistance. Have been considered. However, even in this case, the heat deformation temperature under a high load is 70 to 80 at most.
° C and its heat resistance is not sufficient. Moreover, when trying to improve the heat resistance of the photocured product, on the other hand, the volume shrinkage at the time of curing is increased, leading to a decrease in dimensional accuracy. A photocurable resin composition that simultaneously satisfies the above properties has not yet been obtained. In general, if the crosslink density in the photocurable resin composition is increased, an improvement in heat resistance can be expected.However, there is a tendency that the volume shrinkage during curing is increased by simultaneously increasing the crosslink density, Improvement and reduction of volumetric shrinkage during curing have a trade-off relationship.
Therefore, there is a demand for an optical three-dimensional structure that is superior in heat resistance and has a small volume shrinkage during curing by breaking such a trade-off relationship. In addition, in a conventional optical three-dimensional structure, the coefficient of linear thermal expansion is generally 4 × 10 ⁻⁵ cm / cm.
/ ° C or higher, and has a small coefficient of thermal expansion of 3 × 10 ⁻⁵ cm / cm / ° C. or less as in a filler-reinforced super engineering plastic (for example, a glass fiber reinforced polyamide-imide resin). Things have not been obtained,
From this point, there is a demand for an optical three-dimensional structure having a low coefficient of thermal expansion and a small dimensional change even when the temperature changes.

[0007]

Under the circumstances described above, the present inventors:
Various studies have been made in order to obtain an optical three-dimensional structure having excellent heat resistance and small volume shrinkage. When a specific filler is blended into a liquid photocurable resin and subjected to optical three-dimensional molding, volumetric shrinkage upon curing is small, dimensional accuracy is excellent, mechanical properties are good, and thermal deformation temperature is high. And found that an optical three-dimensional object having high heat resistance and excellent heat resistance can be obtained (Japanese Patent No. 2554443 and Japanese Patent Application Laid-Open No. 8-2).
No. 0620).

The present inventors have further advanced the above research. As a result, as a filler, aluminum oxide fine particles having a predetermined particle size and whiskers having a specific size have been particularly selected. A resin composition for optical three-dimensional modeling is prepared by blending both in a liquid photocurable resin at a specific ratio, and optical three-dimensional modeling is performed using the resin composition. It has been found that an optical three-dimensional structure having a higher heat distortion temperature and a higher flexural modulus can be obtained than in the inventions of US Pat. No. 2,554,443 and JP-A-8-20620. Based on the above invention,
As a result of further studies by the present inventors, in the above-described resin composition for optical three-dimensional modeling, when a specific one is used as the aluminum oxide fine particles and the whisker in a specific ratio, the heat distortion temperature under a high load is increased. Extremely high at 300 ° C. or higher, and extremely high in bending elastic modulus of 2000 g / mm ² or more, having unprecedented high heat resistance and high rigidity,
Further, the inventors have found that an optical three-dimensional structure having a very small thermal expansion coefficient of 3 × 10 ⁻⁵ cm / cm / ° C. or less and excellent thermal dimensional stability and high commercial value can be obtained. Completed the invention.

That is, the present invention relates to an optical three-dimensional modeling resin composition, wherein the liquid photocurable resin has an average particle diameter of 3 to 7 based on the total volume of the optical three-dimensional modeling resin composition.
5 to 65% by volume of 0 μm aluminum oxide fine particles, and 5 to 30% by volume of whiskers having a diameter of 0.3 to 1 μm, a length of 10 to 70 μm and an aspect ratio of 10 to 100, and the aluminum oxide fine particles. And a whisker having a total content of 10 to 70% by volume based on the total volume of the resin composition for optical three-dimensional modeling.

The present invention is a method for producing an optical three-dimensional object by performing optical three-dimensional object molding using the resin composition for optical three-dimensional object molding. Furthermore, the present invention relates to an optical three-dimensional structure obtained using the above-described resin composition for optical three-dimensional structure, and in particular, a load of 18.5 kg / mm.
^{As a} preferred embodiment, an optical three-dimensional structure having a heat distortion temperature of 300 ° C. or higher and a flexural modulus of 2000 kg / mm ² or higher measured under a high load is included. In the present invention, the coefficient of linear thermal expansion obtained by using the above-described resin composition for optical three-dimensional modeling is 0.5 × 10 ^{−5 to} 3 × 1.
It includes an optical three-dimensional structure having 0 ^-5 cm / cm / ° C.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The resin composition for optical three-dimensional modeling of the present invention capable of forming an optical three-dimensional molded article having a small volumetric shrinkage upon curing, high thermal deformation temperature and flexural modulus, and a low coefficient of linear thermal expansion is as described above. As described above, it contains aluminum oxide fine particles having a specific particle size and whiskers having a specific size.

The aluminum oxide fine particles used in the present invention must have an average particle diameter of 3 to 70 μm. When the average particle size of the aluminum oxide fine particles is less than 3 μm, the viscosity of the optical three-dimensional modeling resin composition increases,
It becomes difficult to mix a predetermined amount of aluminum oxide fine particles necessary for imparting a high thermal deformation temperature and a high flexural modulus to an optical three-dimensional object, and the handleability during the optical three-dimensional object becomes poor. On the other hand, when the average particle size of the aluminum oxide fine particles exceeds 70 μm, the viscosity of the resin composition for optical three-dimensional modeling does not increase so much, but the irradiation energy such as ultraviolet rays is scattered during the optical three-dimensional modeling, and the modeling accuracy is reduced. In addition, the molding accuracy is reduced due to the limitation of the film thickness per layer when performing optical three-dimensional modeling. The average particle size of the aluminum oxide fine particles is preferably from 10 to 60 μm, and more preferably from 15 to 50 μm, from the viewpoints of handleability of the resin composition for optical three-dimensional modeling, moldability, and dimensional accuracy of the obtained optical three-dimensional molded article. Is more preferable. In addition,
The average particle size of the aluminum oxide fine particles referred to in the present specification,
It refers to the average particle size of the aluminum oxide fine particles measured by a scanning electron microscope, and details thereof are as described in the following Examples.

The aluminum oxide fine particles used in the present invention may be transparent or opaque. In addition, the shape of the aluminum oxide fine particles should be smooth and spherical, so that irregular reflection of irradiation energy during optical three-dimensional modeling is reduced, so that it is possible to obtain an optical three-dimensional model with high dimensional accuracy, It is preferable because the viscosity of the three-dimensional modeling resin composition does not increase, and an optical three-dimensional modeling resin composition having excellent handleability and molding properties can be obtained. In particular, as aluminum oxide fine particles,
The use of a true sphere having a sphericity having a relative standard deviation value of 5 or less represented by the following formula (1) or a shape close to the sphere prevents the viscosity of the optical three-dimensional modeling resin composition from increasing, It is preferable from the viewpoint of the dimensional accuracy of the obtained optical three-dimensional structure, more preferably one having a relative standard deviation value of 1 or less, and still more preferably one having a relative standard deviation of 0.5 or less.

[0014]

(Equation 2)

The whiskers used in the optical three-dimensional modeling resin composition of the present invention must have a diameter of 0.3 to 1 μm, a length of 10 to 70 μm, and an aspect ratio of 10 to 100. Is 0.3-0.7 μm and length is 2
The aspect ratio is preferably 0 to 50 μm and the aspect ratio is 20 to 70. When the diameter of the whisker is less than 0.3 μm,
The heat deformation temperature, flexural modulus, and mechanical properties of the optical three-dimensional structure become low. On the other hand, if it exceeds 1 μm, the viscosity of the optical three-dimensional structure resin composition increases, and the handleability and the formability decrease. . Further, when the length of the whisker is less than 10 μm, the heat deformation temperature, the flexural modulus and the mechanical properties are lowered, while when it exceeds 70 μm, the viscosity of the optical three-dimensional modeling resin composition is increased, and the handling property is increased.
The formability decreases. In particular, it is important that the aspect ratio of the whisker is in the range of 10 to 100 described above,
If the aspect ratio is less than 10, the mechanical properties are not improved, and the effect of reducing the volume shrinkage during optical three-dimensional modeling cannot be obtained. On the other hand, if the aspect ratio exceeds 100, the viscosity of the resin composition for optical three-dimensional modeling increases. And the modeling operation becomes difficult, and the lateral accuracy of the optical three-dimensionally shaped object is reduced. The dimensions and aspect ratio of the whisker referred to in this specification are as follows:
It refers to the dimensions and aspect ratio measured using a laser diffraction / scattering particle size distribution analyzer, the details of which are described in the Examples section below.

The type of whisker is not particularly limited.
Aluminum-based whiskers are preferably used because they have a high affinity for the aluminum oxide fine particles and can provide an optical three-dimensional structure having high heat distortion temperature, flexural modulus and mechanical strength. In this case, examples of the aluminum-based whiskers include aluminum borate-based whiskers, aluminum oxide-based whiskers, and aluminum nitride-based whiskers, and one or more of these aluminum-based whiskers can be used.

The resin composition for optical three-dimensional modeling of the present invention comprises:
Based on the total volume of the resin composition for optical three-dimensional modeling, the aluminum oxide fine particles are contained in a proportion of 5 to 65% by volume and the whiskers are contained in a proportion of 5 to 30% by volume. The content is 1 based on the total volume of the optical three-dimensional modeling resin composition.
It needs to be 0 to 70% by volume.

The content of the aluminum oxide fine particles is 5% by volume based on the total volume of the resin composition for stereolithography.
If it is less than the above, the effect of improving the thermal deformation temperature and the bending elastic modulus and the effect of lowering the linear thermal expansion coefficient by blending the aluminum oxide fine particles will not be exhibited. Of the aluminum oxide fine particles, and the average particle size of the aluminum oxide fine particles used is greatly restricted.

When the content of the whisker is less than 5% by volume based on the total volume of the resin composition for optical three-dimensional modeling, the effect of improving the heat deformation temperature and the flexural modulus by adding the whisker is obtained. The effect of lowering the coefficient of linear thermal expansion is no longer exhibited, and the mechanical strength of the optical three-dimensional molded article becomes low. On the other hand, if it exceeds 30% by volume, the viscosity of the optical three-dimensional molded resin composition increases and the optical It is difficult to perform three-dimensional modeling, and the dimensional accuracy of an optical three-dimensional model is reduced.

If the total content of the aluminum oxide fine particles and the whiskers is less than 10% by volume based on the total volume of the resin composition for optical three-dimensional modeling, volume shrinkage during optical three-dimensional modeling increases. , The dimensional accuracy of the obtained optical three-dimensional object is reduced, and the thermal deformation temperature, flexural modulus, and mechanical strength of the optical three-dimensional object are low,
Further, a decrease in the coefficient of thermal expansion cannot be achieved. On the other hand, if it exceeds 70% by volume, the viscosity of the resin composition for optical three-dimensional molding increases, resulting in poor handling and molding properties. The dimensional accuracy of the object decreases.

In the optical three-dimensional modeling resin composition of the present invention, based on the total volume of the optical three-dimensional modeling resin composition,
The content of the aluminum oxide fine particles is 10 to 55% by volume, the content of the whisker is 5 to 25% by volume, and the total content of the aluminum oxide fine particles and the whisker is 2
When the content is 0 to 60% by volume, the viscosity, handleability, and moldability of the resin composition for optical three-dimensional modeling are improved, and the volumetric shrinkage during optical three-dimensional modeling is small, and the obtained optical three-dimensional molded article is obtained. This is preferable because the dimensional accuracy of the resulting optical three-dimensional structure can be further improved, and the thermal deformation temperature, flexural modulus, and mechanical strength of the obtained optical three-dimensional structure can be further increased, and the coefficient of linear thermal expansion can be reduced. Among them, the high heat deformation temperature described above,
It has excellent properties such as high flexural modulus, high mechanical properties, and low volumetric shrinkage, and has a coefficient of linear thermal expansion of 0.5 × 10 ^-5 to
In order to smoothly obtain an optical three-dimensional structure having a low coefficient of thermal expansion in the range of 3 × 10 ⁻⁵ cm / cm / ° C., in the resin composition for optical three-dimensional modeling of the present invention, It is preferable that the content of the aluminum oxide fine particles is 15 to 55% by volume, the content of the whisker is 5 to 20% by volume, and the total content of the aluminum oxide fine particles and the whisker is 20 to 60% by volume. Particularly, based on the total volume of the resin composition for optical three-dimensional modeling, the content of the aluminum oxide fine particles is set to 20 to 50% by volume, the content of the whisker is set to 10 to 20% by volume, and When the total content of whiskers is 30 to 60% by volume, the coefficient of linear thermal expansion is 2 × 10
It is possible to smoothly obtain an optical three-dimensional structure having extremely excellent thermal dimensional stability of ^-5 cm / cm / ° C or less.

In the present invention, one or both of the aluminum oxide fine particles and the whiskers may be surface-treated with a silane coupling agent, and both the aluminum oxide fine particles and the whiskers may be surface-treated with a silane coupling agent. preferable. When the aluminum oxide fine particles and / or whiskers are surface-treated with a silane coupling agent, an optical three-dimensional structure having a higher heat distortion temperature, flexural modulus, and mechanical strength can be obtained. In that case, as the silane coupling agent,
Any of the silane coupling agents conventionally used for surface treatment of the filler can be used, and preferred silane coupling agents include aminosilane, epoxysilane, vinylsilane and (meth) acrylsilane. More specifically, γ-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-
Aminosilanes such as aminopropyltriethoxysilane and N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane; β- (3,4-epoxycyclohexyl) -ethyltrimethoxysilane and γ-glycidoxypropyltrimethoxy Epoxy silanes such as silanes;
Vinyl silanes such as vinyl trichlorosilane, vinyl diethoxy silane, and vinyl-tris (β-methoxyethoxy silane); and (meth) acryl silanes such as trimethoxy silane methacrylate. Alternatively, two or more kinds can be used.

When the surface treatment of aluminum oxide fine particles and / or whiskers is performed with a silane coupling agent, the manner in which the silane coupling agent exerts its function may differ depending on the type of photocurable resin used. Therefore, a silane coupling agent suitable for each photo-curable resin is selected and aluminum oxide fine particles and / or
Alternatively, it is preferable to perform a whisker surface treatment. For example, it is preferable to use vinylsilane and / or (meth) acrylsilane for a photocurable resin mainly composed of a vinyl-based unsaturated compound, and it is preferable to use epoxysilane for a photocurable resin mainly composed of an epoxy-based compound. .

In the present invention, as the liquid photocurable resin, any of the liquid photocurable resins for optical three-dimensional modeling containing a photopolymerizable compound and a photopolymerization initiator can be used. Although not limited, the liquid photocurable resin that can be used in the present invention includes, for example, acrylate photocurable resin, urethane acrylate photocurable resin, epoxy photocurable resin, epoxy acrylate photocurable resin. Resin,
Examples thereof include a vinyl ether-based photocurable resin. In that case, the photocurable resin may contain only one kind of the above-described photocurable resins, or may contain two or more kinds. Depending on the type of photocurable resin contained in the photocurable resin, the type of photopolymerization initiator may also be, for example, a photoradical polymerization initiator, a photocationic polymerization initiator, a photoradical polymerization initiator and a photocationic polymerization. Each may be different, such as a combination of initiators.

Although not limited, specific examples of the liquid photocurable resin which can be used in the present invention are as follows. (1) Monofunctional and polyfunctional polyester (meth) acrylates, polyether (meth) acrylates, etc. are mainly used, and if necessary, monofunctional (meth) acrylate monomers and polyfunctional (meth) acrylate monomers are mixed, A radical polymerization type liquid acrylate photocurable resin containing a photoradical polymerization initiator. (2) Monofunctional or polyfunctional epoxy (meth) acrylate as a main component, and if necessary, a monofunctional (meth) acrylate monomer and a polyfunctional (meth) acrylate monomer mixed therein, and a photo-radical polymerization initiator and Liquid epoxy acrylate-based photocurable resin containing a cationic photopolymerization initiator as required. (3) Monofunctional and polyfunctional urethane (meth) acrylates are mainly used, and if necessary, a monofunctional (meth) acrylate monomer and a polyfunctional (meth) acrylate monomer are mixed, and a photo-radical polymerization initiator is added thereto. A radical polymerization type liquid urethane acrylate-based photocurable resin contained therein.

(4) One or more of an aliphatic diepoxy compound, an alicyclic diepoxy compound and an aromatic diepoxy compound are mainly used, and if necessary, a monofunctional (meth) acrylate monomer, a polyfunctional (meth) ) A liquid epoxy-based photocurable resin in which an acrylate monomer is mixed and a photocationic polymerization initiator and, if necessary, a photoradical polymerization initiator are contained. (5) A liquid vinyl ether photocurable resin mainly composed of an aliphatic divinyl ether compound, an alicyclic divinyl ether compound, an aromatic divir ether compound, etc., and containing a photo-radical polymerization initiator. (6) A mixed type containing at least two of an acrylate compound, a urethane acrylate compound and an epoxy acrylate compound, and further containing a photoradical polymerization initiator and, if necessary, a photocationic polymerization initiator. Liquid photocurable resin in mold.

In any of the liquid photocurable resins (1) to (6) described above, the above-mentioned aluminum oxide fine particles and whiskers are blended with the above photocurable resins in the above-mentioned proportions, and the optical composition of the present invention is used. By preparing a three-dimensional modeling resin composition and performing optical three-dimensional modeling using it, the volume shrinkage during curing is small and the dimensional accuracy is excellent, and the heat deformation temperature and flexural modulus are large and heat resistance An optical three-dimensional object having excellent rigidity and high mechanical strength can be obtained. Among them, the liquid photocurable resin has been developed by the present inventors. (I) The following general formula (I);

[0028]

Embedded image In the formula, R ¹ is a hydrogen atom or a methyl group, p is 1 or 2, and when p is 2, one or both R ¹ are methyl groups, A is a diol or triol residue, D is
1-4 divalent or trivalent unsubstituted or substituted hydrocarbon group, E is the formula _{:-( CH 2 CH 2 O) s-} ( wherein s
A (poly) ethylene oxide group represented by the following formula:-[(CH ₂ CH (CH ₃ ) O] t-(where t represents an integer of 1 to 4) ( poly) propylene oxide group, or a group of the formula _{:-( CH 2 CH 2 O) u} [(CH 2 C
_{H (CH 3) O] v-} ( wherein u and v, respectively 1-3
Of integers a and the sum of u and v are represented by a is) 2-4 (poly) ethylene oxide-propylene oxide group, R ² is a hydrogen atom or an alkyl group, q is 1 or 2, and r is 3 or (Ii) a radically polymerizable compound other than the above urethaneized acrylic compound; and (iii) A photopolymerization initiator; wherein the weight ratio of the urethane-containing acrylic compound: the radical polymerizable compound is 8;
It is more preferable to use a liquid photocurable resin of 0:20 to 10:90.

The above-mentioned aluminum oxide fine particles and the above-mentioned whiskers are added to a liquid photo-curable resin comprising at least one kind of the above urethane-containing acrylic compound (I), another radically polymerizable compound and a photopolymerization initiator. When using the resin composition for optical three-dimensional modeling contained in a specific ratio, the heat deformation temperature measured under a high load of 18.5 kg / mm ² is 300 ° C. or more, and the flexural modulus is 20.
00 kg / mm ² or more, coefficient of linear thermal expansion is 3 × 10 ⁻⁵ cm
/ Cm / ° C or less, which is super heat resistant and highly rigid, and has excellent thermal dimensional stability.
Good dimensional accuracy can be obtained while keeping the volume shrinkage during curing small. Such an optical three-dimensional structure having super heat resistance, high rigidity, and excellent thermal dimensional stability has not been known so far, and can be obtained for the first time by the present invention.

In the urethane-containing acrylic compound (I) preferably used in the present invention, R ¹ is a hydrogen atom or a methyl group, p is 1 or 2, and when p is 2, two groups; CH ₂ = C (R ¹⁾ groups R ¹ in one or both of the radicals -COO- are methyl groups.
Two groups when p is 2 in the urethane acrylate compound (I); both groups R in CH ₂ ＝ C (R ¹ ) —COO—
^{If 1} is a hydrogen atom, it has to go through glycerin diacrylate, which is synthetically extremely toxic, carcinogenic and skin irritating, and cannot be practically used.

The urethane-containing acrylic compound (I)
In formula (I), the group A is a diol or triol residue (that is, a group obtained by removing a hydroxyl group from a diol or triol). Examples of the group A include diols and triol residues such as aliphatic diols having 2 to 5 carbon atoms, alicyclic diols, aromatic diols, aliphatic triols, alicyclic triols, and aromatic triols. Among them, the group A is a diol residue such as ethylene glycol, propylene glycol, butylene glycol, ethoxylated bisphenol A, spiro glycol, glycerin, trimethylolpropane, 5-methyl-1,2,2,
It is preferably a triol residue such as 4-heptanetriol or 1,2,6-hexanetriol, more preferably an alcohol residue of ethylene glycol or glycerin, and more preferably an alcohol residue of glycerin. More preferred.

In the urethane-containing acrylic compound (I), the group D is a divalent or trivalent unsubstituted or substituted hydrocarbon group, and the group D is an unsubstituted or substituted hydrocarbon group having 6 to 20 carbon atoms. It is preferably an aliphatic, aromatic or alicyclic divalent or trivalent hydrocarbon group. Preferred examples of the group D in the urethane acrylic compound (I) include an isophorone group, a tolylene group, a 4,4′-diphenylmethane group, a naphthylene group, a xylylene group, a phenylene group, and 3,3′-dichloro-4,4 ′. -Phenylmethane group, toluylene group, hexamethylene group, 4,4'-dicyclohexylmethane group, hydrogenated xylylene group, hydrogenated diphenylmethane group, triphenylenemethane group, tetramethylxylene group and the like. Among them, it is more preferable that the group D is an isophorone group and / or a tolylene group. In this case, the volumetric shrinkage at the time of curing of the optical three-dimensional structure obtained from the liquid photocurable resin composition of the present invention can be improved. It is easier to balance heat resistance.

Then, the urethane-modified acrylic compound (I)
In the above, when the group D is a divalent hydrocarbon group, q = 1
And when the group D is a trivalent hydrocarbon, q = 2
become. In the urethane acrylic compound (I), the group E is represented by the formula:-(CH ₂ CH ₂ O) s- (where s is 1 to 5).
A (poly) ethylene oxide group represented by the following formula:-[(CH ₂ CH (CH ₃ ) O] t-
Represented by (poly) propylene oxide group, or a group of the formula :-( CH ₂ CH ₂ O) u in is an integer of 1 to 4) [(CH _{2
CH (CH 3) O] v-} ( wherein u and v respectively 1
An integer of 3 and the sum of u and v is 2 to 4). Group E, ie (poly) represented by the above formula
In the ethylene oxide group or the (poly) propylene oxide group, s or t is preferably an integer of 1 to 3, more preferably 1 or 2. In the (poly) ethylene oxide propylene oxide group represented by the above formula, the sum of u and v is 2 or 3
Is preferably, and more preferably 2. In particular, urethane acrylate compound (I) in the group E has the _{formula: - [(CH 2 CH (} CH 3) O] t- ( wherein t is preferably 1 to 3, represented by a more preferably 1 to 2) (Poly) propylene oxide group, a photocurable resin composition having a higher heat distortion temperature, better heat resistance, less volumetric shrinkage upon curing, and relatively low viscosity is obtained. In the urethane acrylic compound (I), the group R ² is a hydrogen atom or an alkyl group, and r is 3 or 4. The group R ² is a lower alkyl group having 1 to 4 carbon atoms. Is more preferable, and more preferably a methyl group or an ethyl group.

Although not limited, examples of the urethane acrylate compound (I) include the following. In the above general formula (I), p is 1, R ¹ is a hydrogen atom or a methyl group, q is 1, and D is a divalent unsubstituted or substituted aromatic, aliphatic or alicyclic hydrocarbon group, r Is a urethanized acrylic compound (I) of 4, wherein one of the carbon atoms is the center and its carbon atom has the formula: CH ₂ ＣC (R ¹ )
COO-A-OOC-NH-D-NH-COO-EC
A urethane acrylate compound in which four urethane acrylate groups represented by H ₂ — are bonded. In the above general formula (I), p is 1, R ¹ and R ²
Is a hydrogen atom or a methyl group, q is 1 and D is a divalent unsubstituted or substituted aromatic, aliphatic, alicyclic hydrocarbon group,
a urethanized acrylic compound (I) wherein r is 3, wherein one of the carbon atoms is the center and the carbon atom (ie, the carbon atom to which the remaining group R ² is bonded) has the formula: CH ₂ =
C (R ¹ ) COO-A-OOC-NH-D-NH-COO
A urethane acrylate group represented by —E—CH ₂ —
A urethanized acrylic compound that is bonded individually.

In the above general formula (I), p is 2
Wherein ^one of the two R ¹ is a hydrogen atom and the other is a methyl group, q is 1 and D is a divalent unsubstituted or substituted aromatic, aliphatic, alicyclic hydrocarbon group, r Is a urethane-containing acrylic compound (I) having a carbon atom centered on one carbon atom and having the formula: [CH ₂ ＣC (R ¹ ) CO
O] ₂ -A-OOC-NH-D-NH-COO-EC
A urethane acrylate compound in which four urethane acrylate groups represented by H ₂ — are bonded [ie, a urethane acrylate compound (I) having eight (meth) acrylate groups in one molecule]. In the above general formula (I), p is 2 and two R ¹
Is a hydrogen atom and the other is a methyl group, R ² is a hydrogen atom or a methyl group, q is 1 and D is a divalent unsubstituted or substituted aromatic, aliphatic, alicyclic hydrocarbon group, r Is a urethane-containing acrylic compound (I) having a carbon atom centered on one carbon atom (that is, the carbon atom to which the remaining group R ² is bonded): [CH ₂ ＣC
(R ¹ ) COO] ₂ -A-OOC-NH-D-NH-COO
A urethane acrylate group represented by —E—CH ₂ —
A urethanized acrylic compound [i.e., a urethanated acrylic compound (I) having six (meth) acrylate groups in one molecule].

In the above general formula (I), p is 1
R ¹ is a hydrogen atom or a methyl group, q is 2, D
Is a trivalent unsubstituted or substituted aromatic, aliphatic, or alicyclic hydrocarbon group, and r is 4;
With one carbon atom as the center and the formula: [CH ₂ ＣC (R ¹ ) COO-A-OOC-N
_{H] 2 -D-NH-COO} -E-CH 2 - with urethane acrylate compound urethane acrylate group is four bonds represented [i.e. (meth) urethanization having 8 acrylate groups in one molecule Acrylic compound (I)]. In the above general formula (I), p is 1, R ¹ and R ² are a hydrogen atom or a methyl group, q is 2, and D is 3
A divalent unsubstituted or substituted aromatic, aliphatic, or alicyclic hydrocarbon group, a urethane acrylate compound (I) in which r is 3, wherein one carbon atom is the center and And the formula: [CH ₂ ＣC (R ¹ ) COO-A-OOC-NH]
_{2 -D-NH-COO-E} -CH 2 - urethane acrylate compound urethane acrylate group is three bond represented by [ie (meth) urethane acrylate compound having 6 acrylate groups in one molecule (I)].

In the above general formula (I), p is 2
Wherein ^one of the two R ¹ is a hydrogen atom and the other is a methyl group, q is 2, and D is a trivalent unsubstituted or substituted aromatic, aliphatic, alicyclic hydrocarbon group, r Is a urethane-containing acrylic compound (I) having a carbon atom centered on one carbon atom and having the formula: [[CH ₂ ＣC (R ¹ ) CO
O] ₂ -A-OOC-NH｝ ₂ -D-NH-COO-E-
A urethane acrylate compound having four urethane acrylate groups represented by CH ₂ — bonded (ie, (meth)
Urethane acrylic compound (I) having 16 acrylate groups in one molecule]. In the above general formula (I), p is 2 and two R ¹
Is a hydrogen atom and the other is a methyl group, R ² is a hydrogen atom or a methyl group, q is 2, and D is a trivalent unsubstituted or substituted aromatic, aliphatic, or alicyclic hydrocarbon group. , R
Is a urethane-containing acrylic compound (I) having a carbon atom centered on 3 and having the formula: {[C
H ₂ ＣC (R ¹ ) COO] ₂ -A-OOC-NH｝ ₂ -D-
A urethane acrylate compound having three bonded urethane acrylate groups represented by NH-COO-E-CH _2- [that is, a urethane acrylate compound (I) having 12 (meth) acrylate groups in one molecule] .

The method for producing the urethane-containing acrylic compound (I) is not particularly limited, but for example, it can be produced as follows. [Example of production method of urethane-modified acrylic compound (I)] (1) The following general formula (II);

[0039]

Embedded image (Wherein R ¹ , A, a and p each represent the same group or number as described above) (meth) acrylate (II) and the following general formula (III);

[0040]

Embedded image The polyisocyanate compound (III) represented by D- (NCO) q + 1 (III) (where D and q are the same groups or numbers as described above) The isocyanate group is reacted in the presence or absence of a diluent comprising a radically polymerizable compound having no reactivity with the isocyanate group using a quantitative ratio such that the isocyanate group remains. IV);

[0041]

Embedded image Wherein R ¹ , A, D, p and q each represent the same group or number as described above, or a reaction product comprising a monoisocyanate compound (IV) represented by the formula: Producing a reaction product containing the radically polymerizable compound together with the compound (IV); (2) a reaction product obtained in the above step (1) with respect to the reaction product obtained in the step (1);

[0042]

(HOE-CH ₂ ) _r -C- (R ² ) _4-r (V) (wherein R ² , E and r each represent the same group or number as described above) The polyol compound (V) represented by the above general formula is reacted by mixing the remaining isocyanate group in the monoisocyanate compound (IV) and the hydroxyl group in the polyol compound (V) at a ratio of 1: 1. A reaction product comprising the urethane-containing acrylic compound (I) represented by (I) or a reaction product containing the radically polymerizable compound together with the urethane-containing acrylic compound (I) is produced.

The other radically polymerizable compound used together with the above-mentioned urethane-containing acrylic compound (I) reacts with the urethane-containing acrylic compound (I) when irradiated with light, and reacts with the radically-polymerizable compound. Can be used as long as it is a radical polymerizable compound having a carbon-carbon unsaturated bond capable of reacting to form a cured product, among which acrylic compounds, allylic compounds and / or vinyl lactams Is preferably used. In that case, the radical polymerizable compound may be a monofunctional compound or a polyfunctional compound, or may use both a monofunctional compound and a polyfunctional compound. Further, the radical polymerizable compound may be a low molecular weight monomer, an oligomer, or, in some cases, a compound having a relatively large molecular weight. The other radically polymerizable compound may be used alone or in combination of two or more.

Although not limited, specific examples of other radically polymerizable compounds that can be used together with the urethane-containing acrylic compound (I) include isobornyl (meth) acrylate, bornyl (meth) methacrylate, dicyclopentenyl ( (Meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl
(Meth) acrylate, (poly) propylene glycol mono
(Meth) acrylates such as (meth) acrylate and t-butyl (meth) acrylate, (meth) acrylamides such as morpholine (meth) acrylamide, monofunctional radically polymerizable compounds such as N-vinylcaprolactone and styrene; Tylopropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane tri (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol (meth)
Acrylate, triethylene glycol (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol (meth) acrylate,
1,4-butanediol di (meth) acrylate, 1,
Multifunctional radical polymerizable such as 6-hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dicyclopentenyl di (meth) acrylate, diallyl phthalate, diallyl fumarate, ethylene oxide-modified bisphenol A diacrylate Compounds can be mentioned.

In addition to the above-mentioned radically polymerizable compounds, epoxy compounds, urethane-containing acrylic compounds other than the urethane-containing acrylic compound (I), and epoxy compounds which have been conventionally used in optical stereolithography resin compositions and the like can be used. A meth) acrylate compound, another ester (meth) acrylate, or the like can be used as another radically polymerizable compound.

The other radically polymerizable compounds described above may be used alone or in combination of two or more. As other radically polymerizable compounds used in combination with the urethane-containing acrylic compound (I), morpholine (meth) acrylamide, dicyclopentenyl di (meth) acrylate, and N-vinylcaprolactam are more preferably used. When cured, it is possible to obtain an optical three-dimensional structure having a smaller volume shrinkage ratio, better dimensional accuracy, higher heat deformation temperature, and excellent heat resistance.

In the liquid photocurable resin used in the resin composition for stereolithography of the present invention, a photopolymerization initiator for polymerizing a photopolymerizable compound is conventionally used in a photocurable resin composition. Any known photopolymerization initiator can be used and is not particularly limited. Although not limited, examples of the photopolymerization initiator that can be used in the present invention include 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexylphenylketone, diethoxyacetophenone, acetophenone, and 3-methylacetophenone. , 2-hydroxymethyl-1-phenylpropan-1-one, 4'-isopropyl-2-hydroxy-2-propiophenone, 2-hydroxy-2-methyl-propiophenone, p-dimethylaminoacetophenone, p- t-butyldichloroacetophenone, p-
t-butyltrichloroacetophenone, p-azidobenzalacetophenone, 1-hydroxycyclohexylphenylketono, benzophenone, methyl o-benzoylbenzoate, Michler's ketone, 4,4′-bisdiethylaminobenzophenone, xanthone, fluorenone, fluorene, benzaldehyde, anthraquinone, Examples include triphenylamine and carbazole. When the radically polymerizable compound in the liquid photocurable resin is a compound having a cationically polymerizable group such as an epoxy group, a photocationic polymerization initiator may be used as a photopolymerization initiator. The type of the cationic polymerization initiator is not particularly limited, and a conventionally known one can be used.

The amount of the photopolymerization initiator used depends on the photopolymerization initiator,
Based on the weight of the liquid photocurable resin before adding the aluminum oxide fine particles and whiskers, generally 0.1 to 0.1
It is preferably 10% by weight, more preferably 1 to 5% by weight.

The resin composition for optical three-dimensional modeling of the present invention comprises:
In addition to the above components, if necessary, a leveling agent,
It may contain a surfactant, an organic polymer modifier, an organic plasticizer and the like.

The viscosity of the photocurable resin composition of the present invention can be adjusted according to the intended use and the mode of use. Generally, the viscosity is measured at room temperature (25 ° C.) when measured using a rotary B-type viscometer.
Is preferably about 5,000 to 100,000 centipoise (cp) from the viewpoints of handleability, optical three-dimensional molding property, and dimensional accuracy of the obtained optical three-dimensional molded article. More preferably about 20,000 cp, and 20,000 to 60,000 c
More preferably, it is p.

When the photocurable resin composition of the present invention is stored in a state capable of blocking light, it is usually used at a temperature of 10 to 40 ° C. for a long period of about 6 to 18 months. It can be stored while maintaining good photocuring performance while preventing denaturation and polymerization. The photo-curable resin composition of the present invention has high heat resistance due to its properties, especially small volume shrinkage and excellent dimensional accuracy when cured by light, and also has high heat deformation temperature and high flexural modulus. It can be used for various applications by taking advantage of its characteristics of high rigidity, low thermal expansion coefficient, and excellent thermal dimensional stability.

In performing optical three-dimensional modeling using the photocurable resin composition of the present invention, any of conventionally known optical three-dimensional modeling methods and apparatuses can be used. Among them, in the present invention, it is preferable to use an active energy ray generated from an Ar laser, a He-Cd laser, a xenon lamp, a metal halide lamp, a mercury lamp, a fluorescent lamp, or the like as light energy for curing the resin, Laser beams are particularly preferably used. When a laser beam is used as the active energy beam, it is possible to increase the energy level and shorten the molding time, and to obtain a three-dimensional object with high modeling accuracy by utilizing the good light condensing property of the laser beam. be able to.

As described above, in performing optical three-dimensional modeling using the photocurable resin composition of the present invention, any of a conventionally known method and a conventionally known stereolithography system apparatus can be adopted, and there is no particular limitation. However, as a typical example of the optical three-dimensional molding method preferably used in the present invention, an active energy ray so as to obtain a cured layer having a desired pattern in a liquid photocurable resin composition containing a light energy absorber. To selectively form a cured layer, and then supply an uncured liquid photocurable resin composition to the cured layer, and similarly irradiate active energy rays to form a cured layer continuous with the cured layer. Can be finally obtained by repeating the operation of laminating a new three-dimensional object to finally obtain a target three-dimensional structure. Then, even if the three-dimensional structure obtained by using it is used as it is, or in some cases, post-curing by light irradiation or post-curing by heat, etc., it is necessary to further improve its mechanical properties and shape stability etc. You may use it.

At this time, the structure, shape, size, and the like of the three-dimensional object are not particularly limited, and can be determined according to each use. Typical application fields of the optical three-dimensional modeling method of the present invention include a model for verifying an external design during a design, a model for checking the functionality of parts, and a resin for producing a mold. Examples include the production of a mold, a base model for producing a mold, and a direct mold for a prototype mold. More specifically, precision parts,
Production of models for electric / electronic parts, furniture, building structures, automobile parts, various containers, castings, dies, mother dies, processing models, and the like. Taking advantage of its excellent heat resistance, high rigidity, and thermal dimensional stability (low thermal expansion coefficient) in particular, prototype high-temperature components, such as designing complex heat transfer circuits and analyzing heat transfer behavior of complex structures. It can be used very effectively in the manufacture of parts for precision parts and in the manufacture of molds for precision parts that require high thermal dimensional stability.

[0055]

EXAMPLES The present invention will be specifically described below with reference to examples and the like, but the present invention is not limited to the following examples. In the following examples, the average particle diameter of the aluminum oxide fine particles and the dimensions and aspect ratio of the whiskers were determined as follows. In addition, the tensile strength, tensile elongation, bending strength, flexural modulus, heat deformation temperature and coefficient of linear thermal expansion of the optical three-dimensional object obtained by optical three-dimensional molding, and the volumetric shrinkage during optical three-dimensional molding are as follows. I asked.

[Average Particle Size of Aluminum Oxide Fine Particles] Aluminum oxide fine particles are scattered on a sample stage of an electron microscope so that the individual particles do not overlap as much as possible. Formed with a thickness of 200 ~ 300mm, 1
Observation was carried out at a magnification of 0000 to 30,000, and the particle size was measured using a Luzex 50 manufactured by Nippon Regulator Co., Ltd.
0 "), the area equivalent circle diameter of at least 100 aluminum oxide fine particles was determined, and the average value was obtained.

[Dimensions and aspect ratio of whisker]
Using a laser diffraction / scattering particle size distribution analyzer (“LA-7000” manufactured by Matoba Seisakusho Co., Ltd.), whiskers are dispersed in ion-exchanged water at a ratio of 1% by weight using ion-exchanged water as a dispersion medium. The particle size distribution was examined, and the particle size at the 10% portion (D10) from the smaller one was defined as the diameter (fiber diameter), and the particle size at the 90% portion (D90) was defined as the length (fiber length). When the aspect ratio is D90 / D
It was determined as 10.

[Tensile strength and tensile elongation of optical three-dimensional molded article] Using a dumbbell-shaped test piece manufactured by optical three-dimensional molding, the tensile strength and tensile elongation were measured in accordance with JIS K 7113.

[Bending strength of optical three-dimensional object] JIS
A test piece compliant with K 7207 was manufactured by optical three-dimensional molding, and the bending strength was measured according to JIS K 7207.

[Flexural Modulus of Optical Three-dimensional Object] JIS
A test piece compliant with K 7207 was manufactured by optical three-dimensional molding, and the flexural modulus was measured according to JIS K 7207.

[Thermal Deformation Temperature of Optical Three-Dimensional Object] Using a dumbbell-shaped test piece manufactured by optical three-dimensional molding, method A (load 18.5) according to JIS K7207
kg / mm ² ).

[Coefficient of linear thermal expansion of optical three-dimensional molded article] A rectangular column-shaped test piece (dimensions: 5 mm × 5 mm × 12 mm) in accordance with JIS K7197 is manufactured by optical three-dimensional modeling, and the test piece is used to conform to JIS K7197. The coefficient of linear thermal expansion was measured according to the standard, and the value from room temperature to 150 ° C. was averaged to obtain the coefficient of linear thermal expansion.

[Volume shrinkage during optical three-dimensional modeling] The specific gravity (d ₁ ) of the photocurable resin composition before photocuring used in the optical three-dimensional modeling, and the optical three-dimensional model obtained by the optical three-dimensional modeling The specific gravity (d ₂ ) of the molded article (dumbbell-shaped test piece) was measured, and the volume shrinkage (%) was determined by the following equation (2).

[0064]

## EQU3 ## Volume shrinkage (%) = {(d ₂ −d ₁ ) / d ₂ } × 100 (2)

<< Synthesis Example 1 >> [Production of Reaction Product Containing Urethaneated Acrylic Compound (I) and Radical Polymerizable Compound] (1) Inner volume 50 liter equipped with stirrer, temperature controller, thermometer and condenser 8880 g of isophorone diisocyanate, 9060 g of morpholine acrylamide and 10.0 g of dibutyltin dilaurate
And heated in an oil bath so that the internal temperature would be 80 to 90 ° C. (2) A solution prepared by uniformly mixing and dissolving 7.0 g of methylhydroquinone in 8560 g of glycerin monomethacrylate monoacrylate was charged into a dropping funnel with a side tube, which was previously kept at 50 ° C., and the solution in the dropping funnel was added to the solution. The contents in the flask of the above (1) were dropped and mixed under stirring in a nitrogen atmosphere while maintaining the temperature of the contents of the flask at 80 to 90 ° C., and reacted by stirring at the same temperature for 2 hours. (3) Then, after lowering the temperature of the contents of the flask to 60 ° C., 4 mol of propylene oxide adduct of pentaerythritol charged in another dropping funnel (1 mol of propylene oxide was added to each of the four hydroxyl groups of pentaerythritol) 3660 g was quickly added dropwise, and the reaction was carried out for 4 hours while maintaining the temperature of the contents of the flask at 80 to 90 ° C. to produce a reaction containing the urethane-containing acrylic compound (I) and the radically polymerizable compound (morpholine acrylamide). The product was produced, and the obtained reaction product was taken out of the flask while being warm. (4) The resulting reaction product was a colorless viscous liquid at normal temperature (25 ° C.). The urethane-containing acrylic compound (I) contained in the reaction product obtained in Synthesis Example 1 has the following general formula (I): p = 2,
It is a urethane acrylate compound in which two R ¹ = hydrogen atom and methyl group, A = glycerin residue, q = 1, D = isophorone group, E = propylene oxide group (t = 1), r = 4.

Example 1 (1) The urethane-containing acrylic compound (I) obtained in Synthesis Example 1 was placed in a three-necked flask having an internal volume of 5 liters equipped with a stirrer, a cooling tube, and a dropping funnel with side tubes. 2020 g of a reaction product containing a radical polymerizable compound, 454 g of morpholine acrylamide and 1060 g of dicyclopentanyl diacrylate were charged, and the atmosphere was replaced by degassing under reduced pressure.
Next, 118 g of 1-hydroxycyclohexyl phenyl ketone (“Irgacure 184” manufactured by Ciba-Geigy; photoradical polymerization initiator) in an environment where ultraviolet rays are blocked.
Was added and mixed and stirred at a temperature of 25 ° C. until completely dissolved (mixing and stirring time: about 1 hour) to obtain a photocurable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid.

(2) 3652 g of the photocurable resin obtained in the above (1) was placed in a universal stirrer (Dalton Co., Ltd .; internal volume: 10 liters), and a leveling agent ("Super Dyne" manufactured by Takemoto Yushi Co., Ltd.) was added thereto. V201 ") 38 g, an acrylic silane coupling agent [manufactured by Toshiba Silicone Co., Ltd .;
aluminum oxide fine particles treated with γ (methacryloxypropyl) trimethoxysilane [average particle size = 15 μm]
m, relative standard deviation of sphericity according to the above equation (1) =
0.3 (made by Madomatex Co., Ltd.
-509 "] (24.3% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition), and aluminum borate whisker (Shikoku) treated with the same acrylic silane coupling agent. "Arbolex YS-4" manufactured by Kasei Kogyo Co., Ltd .;
2409 g (14.6% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) having a thickness of 7 μm and an aspect ratio of 50 to 70) was added thereto, followed by stirring for one day and defoaming. , A liquid photocurable resin composition containing aluminum oxide fine particles and whiskers (viscosity of about 4 at 25 ° C.)
8,000 cp).

(3) Using the resin composition for optical three-dimensional molding obtained in (2) above, a water-cooled Ar laser using an ultra-high-speed optical molding system (“SOLIFORM500” manufactured by Teijin Seiki Co., Ltd.) Light (output 500mW; wavelength 33)
3,351,364 nm) perpendicularly to the surface, and with an irradiation energy of 20 to 30 mJ / cm ² , a slice pitch (lamination thickness) of 0.05 mm, and an optical path with an average molding time of 2 minutes per layer. An optical three-dimensional object in the form of a dumbbell test piece for measuring tensile strength, tensile elongation, flexural strength, flexural modulus and thermal deformation temperature was produced by three-dimensional modeling. After washing the obtained optical three-dimensional structure with isopropyl alcohol, it was post-cured by irradiating it with 3 KW ultraviolet rays for 10 minutes. The tensile strength, tensile elongation, flexural strength, flexural modulus and heat distortion temperature of the optical three-dimensional structure (dumbbell-shaped test piece) thus obtained were measured by the methods described above, and as shown in Table 1 below. there were. Further, the specific gravity (d
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were.

Example 2 (1) A photo-curable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as in (1) of Example 1. (2) 3652 g of the photocurable resin obtained in the above (1)
Was placed in a universal stirrer (manufactured by Dalton Co., Ltd .; internal volume 10 liters), and 26 g of the same leveling agent used in (1) of Example 1 and (2) of Example 1 3772 g of aluminum oxide fine particles ("Admafine A-509" manufactured by Admatechs Co., Ltd.) treated with the same acrylic silane coupling agent (2 based on the total volume of the finally obtained optical three-dimensional modeling resin composition
3.3 vol%), and 1 of aluminum borate whiskers (Alvolex YS-4) treated with the same acrylic silane coupling agent as used in (2) of Example 1.
593 g (12.8% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) is added, and the mixture is stirred for one day, defoamed, and contains aluminum oxide fine particles and whiskers. A liquid photocurable resin composition (viscosity at 25 ° C. of about 30,500 cp) was obtained.

(3) Using the resin composition for optical three-dimensional modeling obtained in the above (2), optical three-dimensional modeling was performed in exactly the same manner as (3) in Example 1, and the shape of a dumbbell specimen was obtained. Was manufactured and its tensile strength, tensile elongation, bending strength, flexural modulus and heat deformation temperature were measured by the above-mentioned methods, and the results were as shown in Table 1 below. Further, the specific gravity (d) of the resin composition for optical three-dimensional modeling before photocuring used in the production of the optical three-dimensional molded article of Example 2
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were.

Example 3 (1) A photo-curable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as (1) in Example 1. (2) 3652 g of the photocurable resin obtained in the above (1)
Was placed in a universal stirrer (manufactured by Dalton Co., Ltd .; internal volume: 10 liters), into which 42 g of the same leveling agent used in (2) of Example 1 and that used in (2) of Example 1 were added. 5529 g of aluminum oxide fine particles (“Admafine A-509” manufactured by Admatechs Co., Ltd.) treated with the same acrylic silane coupling agent (2 based on the total volume of the finally obtained optical three-dimensional modeling resin composition)
6.6% by volume), and 2 of aluminum borate whisker (Alvolex YS-4) treated with the same acrylic silane coupling agent as used in (2) of Example 1.
926 g (18.3% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) is added, and the mixture is stirred for one day, defoamed, and contains aluminum oxide fine particles and whiskers. A liquid photocurable resin composition (viscosity at 25 ° C. of about 63,000 cp) was obtained.

(3) Using the resin composition for optical three-dimensional modeling obtained in the above (2), optical three-dimensional modeling was performed in exactly the same manner as (3) in Example 1, and the shape of a dumbbell specimen was obtained. Was manufactured and its tensile strength, tensile elongation, bending strength, flexural modulus and heat deformation temperature were measured by the above-mentioned methods, and the results were as shown in Table 1 below. Furthermore, the specific gravity (d
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were. (4) Further, a rectangular column-shaped test piece for measuring a linear thermal expansion coefficient was manufactured by the method described above using the resin composition for optical three-dimensional modeling obtained in the above (2), and the linear thermal expansion coefficient was described above. 1.25 × 10 ^-5 cm / cm
/ ° C, the coefficient of linear thermal expansion was extremely low, and the thermal dimensional stability was extremely excellent.

Example 4 (1) A photo-curable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as in (1) of Example 1. (2) 3652 g of the photocurable resin obtained in the above (1)
Was placed in a universal stirrer (Dalton Co., Ltd .; internal volume 10 liters), into which 38 g of the same leveling agent used in (2) of Example 1 and that used in (2) of Example 1 were added. Aluminum oxide fine particles treated with the same acrylic silane coupling agent ("NR32" manufactured by Nippon Light Metal Co., Ltd.)
5F-ST ”) [Average particle size = 30 μm, relative standard deviation of sphericity by the above formula (1) = 1.3] 521
9 g (24.3% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) and the same acrylic silane coupling agent used in Example 1 (2). 2409 g of aluminum borate whisker (Alvolex YS-4) (14.6% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) was added, and the mixture was stirred for one day to remove bubbles. By the treatment, a liquid photocurable resin composition (viscosity at 25 ° C. of about 47,000 cp) containing aluminum oxide fine particles and whiskers was obtained.

(3) Using the optical three-dimensional modeling resin composition obtained in the above (2), optical three-dimensional modeling was performed in exactly the same manner as in (3) of Example 1, and the shape of a dumbbell specimen was obtained. Was manufactured and its tensile strength, tensile elongation, flexural strength, flexural modulus and heat distortion temperature were measured by the above-mentioned methods, and the results were as shown in Table 1 below. Furthermore, the specific gravity (d
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were. (4) A rectangular column-shaped test piece for measuring a coefficient of linear thermal expansion is produced by the above-mentioned method using the resin composition for optical three-dimensional modeling obtained in the above (2), and the coefficient of linear thermal expansion is measured by the method described above. 1.05 × 10 ⁻⁵ cm / cm /
° C, the coefficient of linear thermal expansion was extremely small, and the thermal dimensional stability was extremely excellent.

Example 5 (1) A photocurable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as (1) in Example 1. (2) 3652 g of the photocurable resin obtained in the above (1)
Into a universal stirrer (Dalton Co., Ltd .; internal volume 10 liters), into which 38 g of the same leveling agent used in (2) of Example 1 and the same as that used in (2) of Example 1 2,765 g of aluminum oxide fine particles ("Admafine A-509" manufactured by Admatechs Co., Ltd.) treated with an acrylic silane coupling agent (13.3 volumes based on the total volume of the finally obtained optical three-dimensional modeling resin composition) %), Aluminum oxide fine particles (“NR325F-ST” manufactured by Nippon Light Metal Co., Ltd.) treated with the same acrylic silane coupling agent as used in (4) of Example 4 (26).
10 g (12.2% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) and the same acrylic silane coupling agent as used in Example 1 (2). 2668 g of aluminum whisker (Alvolex YS-4) (16.5% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition) is added, and the mixture is stirred for one day to remove bubbles. Thus, a liquid photocurable resin composition (viscosity at 25 ° C. of about 56,000 cp) containing aluminum oxide fine particles and whiskers was obtained.

(3) Using the resin composition for optical three-dimensional modeling obtained in the above (2), optical three-dimensional modeling was performed in exactly the same manner as in (3) of Example 1, and the shape of a dumbbell specimen was obtained. Was manufactured and its tensile strength, tensile elongation, bending strength, flexural modulus and heat deformation temperature were measured by the above-mentioned methods, and the results were as shown in Table 1 below. Further, the specific gravity (d) of the resin composition for optical three-dimensional modeling before photocuring used in the production of the optical three-dimensional molded article of Example 5
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were. (4) Further, a rectangular column-shaped test piece for measuring a linear thermal expansion coefficient is manufactured by the above-mentioned method using the resin composition for optical three-dimensional modeling obtained in the above (2), and the linear thermal expansion coefficient is measured by the above-described method. 1.20 × 10 ⁻⁵ cm / cm /
° C, the coefficient of linear thermal expansion was extremely small, and the thermal dimensional stability was extremely excellent.

Reference Example 1 (1) A photocurable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as (1) in Example 1. (2) Using the photocurable resin obtained in (1) above,
Optical three-dimensional modeling was performed in exactly the same manner as in (3) of Example 1 to produce an optical three-dimensional molded product in the shape of a dumbbell specimen, and its tensile strength, tensile elongation, bending strength, flexural modulus, and thermal deformation were measured. The temperature was measured by the method described above and was as shown in Table 1 below. Further, the specific gravity (d ₁ ) of the resin composition for optical three-dimensional modeling before photocuring used in the production of the optical three-dimensional molded article of Reference Example 1 and the specific gravity (d ₂ ) of the three-dimensional molded article after post-curing. Was measured, and the volumetric shrinkage (%) was determined by the above equation (2). The result was as shown in Table 1 below.

Reference Example 2 (1) A photo-curable resin (viscosity at room temperature: about 2100 cp) as a colorless and transparent viscous liquid was prepared in exactly the same manner as in (1) of Example 1. (2) 2800 g of the photocurable resin obtained in the above (1)
Was placed in a universal stirrer (manufactured by Dalton Co., Ltd .; internal volume 10 liters). 3310 g of glass beads ("GB210C" manufactured by Toshiba Barotini Co., Ltd.) treated with the same acrylic silane coupling agent as above [Average particle size = 15 μm, relative standard deviation of sphericity by the above formula (1) = 0.3] = 3310 g (Based on the total volume of the finally obtained optical three-dimensional modeling resin composition, 32
993 g of aluminum borate whisker (Alvolex YS-4) treated with the same acrylic silane coupling agent as used in (2) of Example 1
(8% by volume based on the total volume of the finally obtained optical three-dimensional modeling resin composition), stirred for one day, defoamed, and liquid photocurable containing glass beads and whiskers. Resin composition (viscosity about 49000c at 25 ° C)
p) was obtained.

(3) Using the optical three-dimensional modeling resin composition obtained in the above (2), optical three-dimensional modeling was performed in exactly the same manner as in (3) of Example 1, and the shape of a dumbbell specimen was obtained. Was manufactured and its tensile strength, tensile elongation, bending strength, flexural modulus and heat deformation temperature were measured by the above-mentioned methods, and the results were as shown in Table 1 below. Further, the specific gravity (d) of the resin composition for optical three-dimensional modeling before photocuring used in the production of the optical three-dimensional molded article of Example 5
₁ ) and the specific gravity (d ₂ ) of the three-dimensional molded article after the post-cure were measured, and the volumetric shrinkage (%) was determined by the above equation (2). there were. (4) A rectangular column-shaped test piece for measuring a coefficient of linear thermal expansion is produced by the above-mentioned method using the resin composition for optical three-dimensional modeling obtained in the above (2), and the coefficient of linear thermal expansion is measured by the method described above. 4.8 × 10 ⁻⁵ cm / cm / ° C.
Met.

[0080]

[Table 1]

From the results shown in Table 1 above, the liquid photocurable resin contains fine particles of aluminum oxide having an average particle size of 3 to 70 μm in an amount within the range of 5 to 65% by volume and a diameter of 0.1 to 0.1%.
3 to 1 μm, length 10 to 70 μm, and aspect ratio 1
In the case of Examples 1 to 5 in which optical three-dimensional modeling is performed using an optical three-dimensional modeling resin composition containing 0 to 100 whiskers in an amount within a range of 5 to 30% by volume, particularly in the case of optical three-dimensional modeling In the case of Examples 1 to 5 in which the liquid photocurable resin containing the urethane-containing acrylic compound (I) was used as the liquid photocurable resin in the molding resin composition, the load was 18.5 kg / mm ² . Thermal deformation temperature measured under high load exceeds 300 ° C and flexural modulus is 2000kg / mm
^It can be seen that an optical three-dimensional structure having a super-heat resistance and high rigidity exceeding ² can be obtained.

More specifically, the urethanized acrylic compound (I), other photopolymerizable compounds, and photopolymerizable compounds developed by the present inventors as a liquid photocurable resin in the resin composition for optical three-dimensional modeling. Reference Example 1 in which optical three-dimensional modeling was performed using an optical three-dimensional modeling resin composition containing an initiator, and glass beads and whiskers were mixed in the optical three-dimensional modeling resin composition of Reference Example 1. In Reference Example 2 in which optical three-dimensional modeling is performed using the resin composition for optical three-dimensional modeling, the heat deformation temperatures of the optical three-dimensional molded article obtained therefrom are 127 ° C. and 251 ° C. The heat distortion temperature of the optical three-dimensional structure obtained in Reference Example 2 is
It can be said that the heat distortion temperature of the conventional optical three-dimensional structure is significantly higher than that of 100 ° C. or less. However, in the case of Examples 1 to 5 of the present invention, such a reference It can be seen from the results of Table 1 above that an optical three-dimensional structure having a higher heat deformation temperature than Examples 1 and Reference Example 2 and an extremely high flexural modulus can be obtained. Moreover, as is apparent from the results of Examples 3 to 5, when the resin composition for optical shaping of the present invention is used, an optical solid having an extremely small coefficient of linear thermal expansion and extremely excellent thermal dimensional stability. A shaped object is obtained.

[0083]

By performing optical three-dimensional molding using the resin composition for optical three-dimensional molding of the present invention, the heat distortion temperature is extremely high and the flexural modulus is extremely high, so that high heat resistance and high heat resistance, which have never existed before, can be obtained. An optical three-dimensional structure having rigidity can be smoothly obtained. Furthermore, when performing optical three-dimensional modeling using the optical modeling resin composition of the present invention,
An optical three-dimensional structure having a coefficient of linear thermal expansion of 3 × 10 ⁻⁵ cm / cm / ° C. or less and having extremely excellent dimensional stability even when the temperature changes can be obtained smoothly. Moreover, the optical three-dimensional object obtained by the present invention has tensile strength, tensile elongation,
It is also excellent in other mechanical properties such as bending strength.
In particular, in the present invention, as the liquid photocurable resin used in the resin composition for optical three-dimensional modeling, a liquid photocurable resin comprising the above urethane-containing acrylic compound (I), another photopolymerizable compound, and a photoinitiator When using, load 1
The heat deformation temperature measured under a high load of 8.5 kg / mm ² is 300 ° C. or more and the flexural modulus is 2000 kg / mm ²
And the coefficient of linear thermal expansion is 3 × 10 ⁻⁵ cm / c
m / ° C. or less, an optical three-dimensional object having super heat resistance and high rigidity, which cannot be expected from conventional optical three-dimensional objects, while maintaining low volume shrinkage during light curing, It can be obtained with good dimensional accuracy.

────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] February 6, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0004

[Correction method] Change

[Correction contents]

As a photocurable resin composition used for a coating material, a photoresist, a dental material, etc., curing of unsaturated polyester, epoxy (meth) acrylate, urethane (meth) acrylate, (meth) acrylate monomer, etc. The addition of a photopolymerization initiator to a hydrophilic resin is widely used. The photocurable resin composition used in the optical three-dimensional molding method includes a photopolymerizable modified (poly) urethane (meth) acrylate compound, an oligoester acrylate compound, an epoxy acrylate compound, an epoxy compound, and a polyimide. And one or more photopolymerizable compounds such as amino-based compounds, aminoalkyd-based compounds and vinyl ether-based compounds as a main component, and a photopolymerization initiator added thereto. No. 204915, JP-A-1-213
No. 304, JP-A-2-28261, JP-A-2-28261
-75617, JP-A-2-145616,
JP-A-3-104626, JP-A-3-11473
No. 2, JP-A-3-114733 and the like disclose various improved techniques.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0008

[Correction method] Change

[Correction contents]

Then, the present inventors have further advanced the above research, and as a result, as a filler, particularly, selected aluminum oxide fine particles having a predetermined particle size and whiskers having a specific size, A resin composition for optical three-dimensional modeling is prepared by blending the two in a liquid photocurable resin at a specific ratio, and optical three-dimensional modeling is performed using the resin composition. It has been found that an optical three-dimensional structure having a higher heat deformation temperature and a higher flexural modulus can be obtained as compared with the inventions of Japanese Patent No. 2554443 and Japanese Patent Application Laid-Open No. H8-20620. Based on the above invention, as a result of further studies by the present inventors, in the above-described resin composition for optical three-dimensional modeling, when a specific thing is used in a specific ratio as aluminum oxide fine particles and whiskers, a high load is obtained. The heat deformation temperature at the bottom is as high as 300 ° C. or more, and the flexural modulus is 2000 kg / mm ^2.
It is extremely high as described above, has unprecedented high heat resistance and high rigidity, and furthermore, has a linear thermal expansion coefficient of 3 × 10 ⁻⁵ cm / cm /
The present inventors have found that an optical three-dimensional structure having a very small value of not more than ° C and excellent thermal dimensional stability and high commercial value can be obtained, and the present invention has been completed based on those findings.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 75/16 C08L 75/16 G03F 7/027 513 G03F 7/027 513 7/028 7/028 // A61K 6/08 A61K 6 / 08 H B29C 67/00 B29C 67/00 C09D 175/16 C09D 175/16

Claims (14)

[Claims] 1. A resin composition for stereolithography, comprising:
In the liquid photocurable resin, based on the total volume of the resin composition for optical three-dimensional modeling, 5 to 65% by volume of aluminum oxide fine particles having an average particle diameter of 3 to 70 μm, and 0.3 to 1 μm in diameter.
m, length 10 to 70 μm and aspect ratio 10 to 10
0 whiskers in a ratio of 5 to 30% by volume, and the total content of the aluminum oxide fine particles and the whiskers is 1 based on the total volume of the resin composition for optical three-dimensional modeling.
A resin composition for optical three-dimensional modeling, which is 0 to 70% by volume. 2. An aluminum oxide fine particle containing 15 to 55% by volume of the aluminum oxide fine particles and 5 to 20% by volume of the whisker based on the total volume of the resin composition for stereolithography. The resin composition for optical three-dimensional modeling according to claim 1, wherein the total content of the whiskers and the whiskers is 20 to 60% by volume based on the total volume of the resin composition for optical three-dimensional modeling. 3. An aluminum oxide fine particle containing the aluminum oxide fine particles in a ratio of 20 to 50% by volume and the whisker in a ratio of 10 to 20% by volume based on the total volume of the resin composition for optical three-dimensional modeling. The resin composition for optical stereolithography according to claim 1 or 2, wherein the total content of the whiskers and the whiskers is 30 to 60% by volume based on the total volume of the resin composition for optical stereolithography. 4. The resin composition according to claim 1, wherein the whiskers are aluminum-based whiskers. 5. The optical three-dimensional object according to claim 1, wherein the whiskers are at least one aluminum whisker selected from aluminum borate whiskers, aluminum oxide whiskers, and aluminum nitride whiskers. Resin composition. 6. The optical solid according to claim 1, wherein the fine particles of aluminum oxide have a sphericity with a relative standard deviation value of not more than 5 represented by the following formula (1). A molding resin composition. (Equation 1) 7. The resin composition for stereolithography according to claim 1, wherein the aluminum oxide fine particles and / or whiskers are surface-treated with a silane coupling agent. 8. The resin composition for optical three-dimensional modeling according to claim 1, wherein the liquid photocurable resin is a liquid photocurable resin containing a photopolymerizable compound and a photopolymerization initiator. . 9. A liquid photocurable resin comprising: (i) a compound represented by the following general formula (I): In the formula, R ¹ is a hydrogen atom or a methyl group, p is 1 or 2, and when p is 2, one or both R ¹ are methyl groups, A is a diol or triol residue, D is
1-4 divalent or trivalent unsubstituted or substituted hydrocarbon group, E is the formula _{:-( CH 2 CH 2 O) s-} ( wherein s
A (poly) ethylene oxide group represented by the following formula:-[(CH ₂ CH (CH ₃ ) O] t-(where t represents an integer of 1 to 4) ( poly) propylene oxide group, or a group of the formula _{:-( CH 2 CH 2 O) u} [(CH 2 C
_{H (CH 3) O] v-} ( wherein u and v, respectively 1-3
Of integers a and the sum of u and v are represented by a is) 2-4 (poly) ethylene oxide-propylene oxide group, R ² is a hydrogen atom or an alkyl group, q is 1 or 2, and r is 3 or (Ii) a radically polymerizable compound other than the above-mentioned urethanized acrylic compound; and (iii) a photopolymerization initiator, wherein the urethanized acrylic compound is Compound: the weight ratio of the radical polymerizable compound is 8
A photocurable resin having a ratio of 0:20 to 10:90.
Item 8. The resin composition for optical three-dimensional modeling according to any one of Items 8 to 8. 10. A method for producing an optical three-dimensional object by performing optical three-dimensional object molding using the resin composition for optical three-dimensional object molding according to any one of claims 1 to 9. 11. An optical three-dimensional molded article obtained by using the resin composition for optical three-dimensional modeling according to any one of claims 1 to 7. 12. The optical three-dimensional structure according to claim 11, wherein a thermal deformation temperature measured under a high load of 18.5 kg / mm ² is 300 ° C. or more, and a flexural modulus is 2000 kg / mm ² or more. 13. A coefficient of linear thermal expansion of 0.5 × 10 ^{−5 to} 3 ×.
The optical three-dimensional structure according to claim 11 or 12, which has a temperature of 10 ^-5 cm / cm / ° C. 14. The thermal expansion coefficient is 0.5 × 10 ⁻⁵ to 2 ×.
The optical three-dimensional structure according to any one of claims 11 to 13, which has a temperature of ^10-5 cm / cm / C.