JP2017119591A - Production method of solid molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a solid molding comprising a sintered body of glass powder, and excellent in compactness.SOLUTION: A production method of a solid molding has steps for: irradiating an activation energy ray to a resin composition containing a hardening resin and glass powder to cure the hardening resin and to form a quench-hardened layer, and obtaining a precursor by repeating the quench-hardened layer until obtaining a prescribed solid molding; and removing the hardening resin by heat-treating the precursor, and sintering the glass powder. In the production method of the solid molding, sintering of the glass powder is performed under a reduced-pressure atmosphere.SELECTED DRAWING: None

Description

  The present invention relates to a method for manufacturing a three-dimensional structure formed of a sintered body of glass powder.

  Conventionally, a method of obtaining a three-dimensional model by laminating resin materials or the like is known. For example, various methods such as an optical modeling method, a powder bed fusion sintering method, and a hot melt deposition (FDM) method have been proposed and put into practical use (see, for example, Patent Document 1).

  Among them, stereolithography is excellent in detailed modeling and accurate size expression, and is widely used. The stereolithography method is to produce a three-dimensional model as follows. First, a modeling stage is provided in a tank filled with a photocurable resin, and the photocurable resin on the modeling stage is irradiated with an active energy ray such as an ultraviolet laser to form a cured layer having a desired pattern. When one cured layer is formed in this way, the modeling stage is lowered by one layer, an uncured photocurable resin is introduced onto the cured layer, and the active energy rays are irradiated onto the photocurable resin in the same manner. A new hardened layer is stacked on the hardened layer. By repeating this operation, a predetermined three-dimensional model is obtained. In the powder sintering method, a modeling stage is provided in a tank filled with resin, metal, ceramics, or glass powder, and the powder on the modeling stage is irradiated with active energy rays to harden a desired pattern by softening deformation. The layer is formed. The three-dimensional structure obtained by such a method is required to have high mechanical strength depending on the application. Patent Document 1 describes that the mechanical strength (mechanical rigidity) of the resulting three-dimensional structure is improved by including inorganic filler particles in the resin composition.

  Derived from the above method, using a resin composition containing glass powder, once producing a three-dimensional precursor, then removing the curable resin by heat-treating the three-dimensional precursor (degreasing) In addition, a method of manufacturing a three-dimensional structure by sintering glass powder has also been proposed (see, for example, Patent Document 2). If it does in this way, it will become possible to manufacture the three-dimensional molded item which has a various shape which consists of a sintered compact of glass powder.

Japanese Patent Laid-Open No. 7-26060 JP 2012-250022 A

  The three-dimensional structure obtained in Patent Document 2 tends to have pores easily remaining inside due to the removal of the curable resin, and tends to be inferior in denseness. As a result, there is a problem that the three-dimensional structure is inferior in mechanical strength, or the pores become scattering factors to reduce the light transmittance and inferior in appearance.

  In view of the above, an object of the present invention is to provide a method capable of producing a three-dimensional structure that is made of a sintered body of glass powder and is excellent in denseness.

  The manufacturing method of the three-dimensional molded item of the present invention includes a step of obtaining a precursor by irradiating a resin composition containing a curable resin and glass powder with active energy rays and curing the curable resin, and heat treating the precursor. This is a method for producing a three-dimensional structure having a step of removing the curable resin and sintering the glass powder, wherein the glass powder is sintered in a reduced-pressure atmosphere.

  As described above, in the method for producing a three-dimensional structure according to the present invention, after preparing a precursor using a resin composition containing a curable resin and glass powder, the precursor is heat-treated in a reduced-pressure atmosphere to obtain glass powder. Sinter. If it does in this way, the bubble which remains after removing curable resin will become easy to discharge | release outside, and it will become easy to improve the compactness of a sintered compact. Therefore, it is possible to improve the mechanical strength and light transmittance of the three-dimensional structure.

  The method for producing a three-dimensional structure of the present invention includes a step of selectively irradiating a layer composed of a resin composition containing a curable resin and glass powder with an active energy ray to form a cured layer having a predetermined pattern, and curing. After forming a new resin composition layer on the layer, the resin composition layer is irradiated with active energy rays to form a new cured layer having a predetermined pattern continuous with the cured layer, thereby obtaining a predetermined three-dimensional structure. A process for producing a precursor by repeatedly laminating a hardened layer until it is obtained, removing the curable resin by heat-treating the precursor, and sintering the glass powder. The glass powder is sintered in a reduced pressure atmosphere. If it does in this way, it will become possible to produce the solid modeling thing which has a complicated shape easily.

  In the manufacturing method of the three-dimensional molded item of this invention, it is preferable that the resin composition contains 1-50% of curable resin and 50-99% of glass powder by volume%. If it does in this way, it will become possible to improve the compactness of the three-dimensional molded item after sintering.

  In the method for producing a three-dimensional structure of the present invention, an ultraviolet curable resin can be used as the curable resin.

  In the manufacturing method of the three-dimensional molded item of this invention, it is preferable that the average particle diameter of glass powder is 1-500 micrometers. In this way, a dense sintered body can be easily obtained.

The method of manufacturing a three-dimensional object of the present invention, the glass powder is in weight% as a _{composition, SiO 2 30~85%, Al 2} O 3 0~30%, B 2 O 3 0~50%, Li 2 O + Na 2 preferably contains O ₊ K 2 O 0~10%. If it does in this way, it will become easy to obtain the solid modeling thing excellent in mechanical strength and chemical durability.

  In the manufacturing method of the three-dimensional molded item of this invention, it is preferable to sinter glass powder within the softening point +/- 100 degreeC of glass powder. In this way, it becomes easy to obtain a dense three-dimensional structure.

  According to the present invention, it is possible to manufacture a three-dimensionally shaped article that is made of a sintered body of glass powder and has excellent denseness.

  The curable resin used in the present invention may be either a photocurable resin or a thermosetting resin, and can be appropriately selected depending on the modeling method employed. For example, when using an optical modeling method, a liquid photocurable resin may be selected, and when a powder sintering method is used, a powdery thermosetting resin may be selected.

  As the photocurable resin, various resins such as a polymerizable vinyl compound and an epoxy compound can be selected. Monofunctional or polyfunctional compound monomers or oligomers are also used. These monofunctional compounds and polyfunctional compounds are not particularly limited. The following are typical examples of photocurable resins.

  Examples of the monofunctional compound of the polymerizable vinyl compound include isobornyl acrylate, isobornyl methacrylate, zinc pentenyl acrylate, bornyl acrylate, bornyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, propylene glycol Examples include acrylate, vinyl pyrrolidone, acrylamide, vinyl acetate, and styrene. Examples of the polyfunctional compound include trimethylolpropane triacrylate, EO-modified trimethylolpropane triacrylate, ethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6 -Hexanediol diacrylate, neopentyl glycol diacrylate, dicyclopentenyl diacrylate, polyester diacrylate, diallyl phthalate and the like. One or more of these monofunctional compounds and polyfunctional compounds can be used alone or in the form of a mixture.

  As a polymerization initiator for the vinyl compound, a photopolymerization initiator is used. As photopolymerization initiators, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, acetophenone, benzophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, Michler's ketone and the like can be mentioned as typical ones, and these initiators can be used alone or in combination of two or more. If necessary, a sensitizer such as an amine compound can be used in combination. It is preferable that the usage-amount of these polymerization initiators is 0.1-10 mass% with respect to a vinyl type compound, respectively.

  Examples of the epoxy compound include hydrogenated bisphenol A diglycidyl ether, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 2- (3,4-epoxycyclohexyl-5,5-spiro-3,4. -Epoxy) cyclohexane-m-dioxane, bis (3,4-epoxycyclohexylmethyl) adipate and the like. When using these epoxy compounds, an energy active cationic initiator such as triphenylsulfonium hexafluoroantimonate can be used.

  Furthermore, a leveling agent, a surfactant, an organic polymer compound, an organic plasticizer, and the like may be added to the photocurable resin as necessary.

  The decomposition temperature of the curable resin used in the present invention is preferably 600 ° C. or lower, 550 ° C. or lower, and particularly preferably 500 ° C. or lower. If the decomposition temperature of the curable resin is too high, it is difficult to remove by heat treatment, and thus there is a tendency that the resulting three-dimensional structure is inferior in density.

Is not particularly limited as glass powder, for example, _{SiO 2 -B 2 O 3 -R '} 2 O (R' is an alkali metal element) based _{glass, SiO 2 -Al 2 O 3 -RO} (R is an alkaline earth metal element ) Glass, SiO ₂ —Al ₂ O ₃ —R ′ ₂ O—RO glass, SiO ₂ —Al ₂ O ₃ —B ₂ O ₃ —R ′ ₂ O glass, SiO ₂ —Al ₂ O ₃ —B ₂ O ₃ —R ′ ₂ O—RO glass, SiO ₂ —R ′ ₂ O glass, SiO ₂ —R ′ ₂ O—RO glass, or the like can be used.

Specific examples of the composition of the glass powder include, as a composition, mass%, SiO ₂ 30 to 85%, Al ₂ O ₃ 0 to 30%, B ₂ O ₃ 0 to 50%, Li ₂ O + Na ₂ O + K ₂ O 0 What contains 10% is mentioned. It is preferable to use a glass powder having the composition because a three-dimensional structure excellent in mechanical strength and chemical durability can be easily obtained. Below, the reason which limited each component as mentioned above is demonstrated. In the following description of the content of each component, “%” represents mass% unless otherwise specified.

SiO ₂ is a component that forms a glass skeleton, is easy to improve chemical durability, and has an effect of suppressing devitrification. Moreover, there exists an effect which raises mechanical strength. The content of SiO ₂ is preferably 30 to 85%, 40 to 75%, particularly 45 to 70%. When SiO ₂ is too small, the effect is difficult to obtain. In addition, the difference between the crystallization temperature and the softening temperature tends to be small. As a result, as will be described later, crystals are likely to precipitate during sintering, and the softening flow of the glass powder is hindered, so that the compactness tends to be lowered and bubbles at the glass grain boundaries are difficult to escape. On the other hand, when the SiO ₂ is too much, it tends to be inferior in moldability softening point higher.

Al ₂ O ₃ is a vitrification stable component. Moreover, the effect of improving chemical durability is high. The content of Al ₂ O ₃ is preferably 0 to 30%, 2.5 to 25%, particularly preferably 5 to 20%. When Al ₂ O ₃ is too large, the softening point is not easily molded to rise. In addition, the meltability and chemical durability are liable to be reduced and the glass is easily devitrified.

B ₂ O ₃ is a component that forms a glass skeleton. Moreover, it is easy to improve chemical durability and has an effect of suppressing devitrification. The content of B ₂ O ₃ is preferably 0 to 50%, 2.5 to 40%, particularly preferably 5 to 30%. If the B ₂ O ₃ content is too large, lowered the melting property, hardly softened during molding tend to manufacture it becomes difficult.

Li ₂ O, Na ₂ O and K ₂ O are components that lower the softening point and facilitate molding. The content of Li ₂ O + Na ₂ O + K ₂ O is preferably 0 to 10%, 0.01 to 10%, 0.1 to 9%, 0.5 to 8%, particularly preferably 1 to 7%. When _{Li 2 O + Na 2 O +} K 2 O is too large, chemical durability tends to decrease. Moreover, a thermal expansion coefficient becomes large and the thermal shock resistance of the three-dimensional molded item obtained will fall easily. _{Incidentally,} Li 2 O, content of each component of Na ₂ O and _{K 2} O is also preferably in the above range.

  In addition to the above components, the glass powder can contain the following components.

  MgO, CaO, SrO, BaO and ZnO are components that improve the meltability by lowering the viscosity without significantly reducing the chemical durability. The total content of these components is preferably 0 to 50%, 0.1 to 50%, 1 to 40%, particularly 2 to 30%. When there is too much content of these components, it will become easy to devitrify.

P ₂ O ₅ is a component that forms a glass skeleton, easily improves light transmittance and chemical durability, and has an effect of suppressing devitrification. The content of P ₂ O ₅ is preferably 0 to 50%, 2.5 to 40%, particularly 5 to 30%. When P ₂ O ₅ is too large, the melting property tends to decrease. In addition, the weather resistance tends to decrease.

The average particle diameter D50 of the glass powder is preferably 1 to ₅₀₀ μm, 1.5 to 100 μm, 2 to ₅₀ μm, and particularly preferably 2.5 to 20 μm. Although it is possible to increase the higher the fill factor the average particle diameter D ₅₀ of the glass powder becomes small, moldability fluidity is lowered curable resin tends to deteriorate. In addition, bubbles (interface bubbles) present at the interface between the glass powder and the curable resin are difficult to escape, and bubbles also remain in the obtained sintered body, which tends to cause a reduction in denseness. On the other hand, it packing ratio the larger the average particle diameter D ₅₀ of the glass powder is likely to decrease, denseness of the sintered body tends to decrease.

In the present invention, the average particle diameter D ₅₀ represents the 50% volume cumulative diameter of the median diameter of the primary particles refers to a value measured by a laser diffraction type particle size distribution measuring apparatus.

  The light transmittance of the glass powder at a wavelength of 400 nm is preferably 5% or more, 10% or more, 30% or more, 50% or more, particularly 70% or more. In particular, in the case of stereolithography, if the light transmittance at a wavelength of 400 nm of the glass powder is too low, the active energy rays are less likely to enter the resin composition and are difficult to cure.

The specific surface area of the glass particles 0.1~3.5m ² /g,0.5~3.2m ² / g, it is particularly preferably 0.75~3m ² / g. If the specific surface area of the glass particles is too small, the particle diameter tends to increase, and the filling rate of the glass particles in the resin composition tends to decrease. On the other hand, when the specific surface area of the glass particles is too large, the fluidity of the resin composition is lowered, the moldability is deteriorated, and the denseness of the sintered body is easily lowered.

  The shape of the glass particles constituting the glass powder is preferably approximately spherical. If it does in this way, since the specific surface area of glass powder becomes small, the viscosity raise of a resin composition can be suppressed and a moldability improves. Moreover, it becomes easy to improve the compactness of the sintered body. The substantially spherical glass particles can be produced, for example, by pulverizing bulk glass and then performing flame polishing (fire polishing).

  The softening point of the glass powder is preferably 1200 ° C. or lower, 1000 ° C. or lower, particularly 900 ° C. or lower. When the softening point of the glass powder is too high, it becomes difficult to obtain a dense sintered body. In addition, spheroidization by flame polishing tends to be difficult. On the other hand, the lower limit of the softening point of the glass powder is not particularly limited, but is practically 250 ° C. or higher, particularly 300 ° C. or higher.

  In addition, it is preferable that the difference (crystallization temperature-softening point) of the crystallization temperature and softening point of glass powder is 10 degreeC or more, 50 degreeC or more, 100 degreeC or more, and especially 200 degreeC or more. If the difference between the crystallization temperature and the softening point is too small, crystals tend to precipitate during sintering, and the softening flow of the glass powder is hindered, or bubbles are likely to remain at the glass grain boundaries, resulting in a decrease in the compactness. It becomes easy. The “crystallization temperature” refers to the obtained crystallization peak temperature measured with a differential thermal analyzer (DTA).

  The surface of the glass powder is preferably treated with a silane coupling agent. When treated with a silane coupling agent, the familiarity between the glass powder and the curable resin is improved, and the moldability is easily improved. Moreover, the weather resistance of glass powder can be improved. As the silane coupling agent, for example, aminosilane, epoxy silane, acrylic silane and the like are preferable. The silane coupling agent may be appropriately selected depending on the curable resin to be used. For example, when a vinyl unsaturated compound is used as the photocurable resin, an acrylic silane silane coupling agent is most preferable, and an epoxy compound is used. When used, it is desirable to use an epoxy silane-based silane coupling agent.

  A resin composition is obtained by mixing the curable resin and glass powder. The proportion of each component in the resin composition is preferably 1% to 50% curable resin and 50% to 99% glass powder in volume%. When the ratio of the curable resin is too small (the ratio of the glass powder is too large), the binding property of the glass powder is inferior and it tends to be difficult to form the precursor. On the other hand, when the ratio of the curable resin is too large (the ratio of the glass powder is too small), pores tend to remain in the three-dimensional structure after firing, and the density tends to be inferior. The preferable range of the content of the resin composition is 5 to 48%, 10 to 45%, particularly 20 to 40% by volume%. Moreover, the preferable range of content of glass powder is 52-95% by volume%, 55-90%, especially 60-80%.

  Next, the manufacturing method of the three-dimensional molded item of this invention using the said resin composition is demonstrated.

  First, the precursor resin is produced by irradiating the obtained resin composition with an active energy ray to cure the curable resin. Below, the specific example of the manufacturing method of the precursor using the resin composition containing photocurable resin is demonstrated.

  First, a modeling stage is provided in a tank filled with the resin composition, and the stage upper surface is positioned so as to have a desired depth (for example, about 0.2 mm) from the liquid surface. By doing in this way, a resin composition layer is prepared on a stage.

  Next, the resin composition layer is irradiated with an active energy ray such as an ultraviolet laser to cure the photocurable resin, thereby forming a cured layer having a predetermined pattern. As the active energy ray, laser light such as visible light and infrared light can be used in addition to ultraviolet light.

  Subsequently, a new resin composition layer is introduced on the formed cured layer. For example, the resin composition can be introduced onto the cured layer by lowering the modeling stage by one layer.

  Thereafter, the new resin composition layer introduced onto the cured layer is irradiated with active energy rays to form a new cured layer continuous with the cured layer.

  By repeating the above operation, the cured layer is continuously laminated to obtain a precursor having a predetermined shape. In addition, the dimensional accuracy of the three-dimensional molded item obtained can be ensured by designing the size and shape of the precursor in consideration of the volume shrinkage in the subsequent heat treatment step.

  Next, the curable resin is removed by heat-treating the obtained precursor, and the glass powder is sintered. Here, it is preferable to first heat treat (degrease) the precursor at the decomposition temperature of the curable resin, and then heat up the precursor at the sintering temperature of the glass powder (two-stage firing). If it does in this way, it will become easy to remove curable resin from a precursor, and it will become easy to improve the compactness of a sintered compact. Degreasing is performed at the decomposition temperature of the curable resin described above. The heat treatment for sintering the glass powder is preferably performed within ± 100 ° C. of the softening point of the glass powder, particularly within ± 50 ° C. of the softening point. When the heat treatment temperature for sintering the glass powder is too low, the sintering is insufficient and the compactness of the sintered body tends to be lowered. On the other hand, when the heat treatment temperature for sintering the glass powder is too high, the glass powder is excessively softened and flowed, and it is difficult to obtain a three-dimensionally shaped object having a desired shape.

Furthermore, in the present invention, the glass powder is sintered in a reduced pressure atmosphere (less than 1 atm (1.013 × 10 ⁵ Pa)). If the pressure at the time of sintering the glass powder is too high, bubbles remaining after removing the curable resin are difficult to be released to the outside, and the denseness of the sintered body tends to be lowered. The atmosphere during sintering of the glass powder is preferably 0.9 × 10 ⁵ Pa or less, 1000 Pa or less, 400 Pa or less, particularly 200 Pa or less. The lower limit of the atmosphere during the sintering of the glass powder is not particularly limited, but is actually 0.001 Pa or more, particularly 0.01 Pa or more.

  Note that at least the glass powder needs to be sintered in a reduced pressure atmosphere, but the step of removing the curable resin may also be performed in a reduced pressure atmosphere. In this case, the atmospheric pressure is preferably in the above range.

  The three-dimensional structure obtained by the production method of the present invention is excellent in denseness. Specifically, the sintered density of the three-dimensional structure is preferably 95% or more, 97% or more, and particularly preferably 99% or more.

  According to the manufacturing method of the present invention, it is possible to easily manufacture a three-dimensional object made of glass having a complicated shape. For example, a dendritic shape (three-dimensional network shape) can be used as an optical filter. Here, by appropriately adjusting the size of the mesh, it can function as a wavelength filter for a desired visible to infrared wavelength.

  EXAMPLES The present invention will be described below based on examples, but the present invention is not limited to the following examples.

  Table 1 shows Examples 1 and 2 of the present invention and a comparative example.

Example 1
(Production of glass powder)
By mass%, SiO ₂ 65.1%, B ₂ O ₃ 8.8%, Al ₂ O ₃ 5.9%, BaO 2.9%, ZnO 4.4%, Li ₂ O 1.5%, Na _The raw materials were prepared so as to have a glass composition of ₂ O 5.7% and K ₂ O 5.7%, melted at 1500 ° C. for 6 hours, and then formed into a film. By pulverizing the film-like glass, a glass powder having an average particle diameter (D ₅₀ ) of 5 μm (ground product; softening point 692 ° C., crystallization temperature 1000 ° C. or more) was obtained. The softening point of the glass powder is a value measured by a fiber elongation method.

(Production of photocurable resin)
First, isophorone diisocyanate, morpholine acrylamide and dibutyltin dilaurate were heated in an oil bath. A solution in which methylhydroquinone was uniformly mixed and dissolved in glycerin monomethacrylate monoacrylate was added, and the mixture was stirred and reacted. A propylene oxide 4 mol adduct of pentaerythritol (1 mol of propylene oxide added to 4 hydroxyl groups of pentaerythritol) was added and reacted to produce a reaction product containing a urethane acrylate oligomer and morpholine acrylamide.

  Morpholine acrylamide and dicyclopentanyl diacrylate were added to the obtained urethane acrylate oligomer and morpholine acrylamide. Further, 1-hydroxycyclohexyl phenyl ketone (photopolymerization initiator) was added to obtain a colorless and transparent acrylic photocurable resin.

(Production of 3D objects)
The glass powder and the photocurable resin obtained above are mixed so that the ratio of the glass powder is 70% by volume and the photocurable resin is 30% by volume. A composition was obtained. The obtained resin composition was poured into a mold made of Teflon (registered trademark) with an inner dimension of 30 mm □. Thereafter, the resin composition was cured by irradiation with light of 500 mW and wavelength of 364 nm, and then annealed at 80 ° C. to obtain a precursor.

  The obtained precursor was degreased by heat treatment under reduced pressure (2 Pa) at 600 ° C. for 1 hour, and then heat treated at 692 ° C. for 10 minutes to sinter the glass powder to obtain a plate-shaped three-dimensional structure.

  About the obtained three-dimensional molded item, the sintered density, the light transmittance, and the bending strength were measured as follows. The results are shown in Table 1.

  The sintered density refers to a value obtained from the formula of (actual density / theoretical density) × 100 (%) based on the actual density and the theoretical density measured by the Archimedes method.

  The light transmittance was measured using a spectrophotometer for a sample having a thickness of 1 mm. The measurement was performed in the wavelength range of 400 to 800 nm, and the maximum light transmittance was shown in the table.

  The bending strength was measured according to JIS R1601 using a sample processed to 4 mm × 40 mm × 3 mm.

(Example 2)
The glass powder obtained in Example 1 was put into a flame of an oxygen burner and formed into a spherical shape. Thereafter, the average particle diameter by classification (D ₅₀₎ was obtained 5μm glass powder (spheroidizing product). Using the obtained glass powder, a three-dimensional model was produced in the same manner as in Example 1, and each characteristic was measured. The results are shown in Table 1.

(Comparative example)
In Example 1, a three-dimensional model was produced by the same method as Example 1 except that the sintering atmosphere of the glass powder was changed to atmospheric pressure (1 atm), and each characteristic was measured. The results are shown in Table 1.

  As is clear from Table 1, in Examples 1 and 2 in which the sintering of the glass powder was performed in a reduced-pressure atmosphere, the sintered density of the obtained three-dimensional structure was 99.9% or more and excellent in denseness. The light transmittance was 89% or more and the bending strength was 130 MPa or more. In Example 2 using the spheroidized glass powder, each characteristic was particularly excellent. On the other hand, in the comparative example in which the glass powder was sintered at atmospheric pressure, the sintered solid density of the obtained three-dimensional object was 94%, the compactness was low, the light transmittance was 5%, and the bending strength was 100 MPa. It was inferior compared with 1 and 2.

Claims (7)

Irradiating an active energy ray to a resin composition containing a curable resin and glass powder to obtain a precursor by curing the curable resin;
Removing the curable resin by heat-treating the precursor and sintering the glass powder;
A method of manufacturing a three-dimensional structure having
A method for producing a three-dimensional structure, comprising sintering glass powder in a reduced-pressure atmosphere. A step of selectively irradiating an active energy ray to a layer comprising a resin composition containing a curable resin and glass powder to form a cured layer having a predetermined pattern;
After forming a new resin composition layer on the cured layer, the resin composition layer is irradiated with active energy rays to form a new cured layer having a predetermined pattern continuous with the cured layer. A step of producing a precursor by repeating lamination of a cured layer until it is obtained,
Removing the curable resin by heat-treating the precursor and sintering the glass powder;
A method of manufacturing a three-dimensional structure having
A method for producing a three-dimensional structure, comprising sintering glass powder in a reduced-pressure atmosphere.   3. The method for producing a three-dimensional structure according to claim 1, wherein the resin composition contains 1% to 50% curable resin and 50% to 99% glass powder by volume%.   The method for producing a three-dimensional structure according to any one of claims 1 to 3, wherein the curable resin is an ultraviolet curable resin.   The method for producing a three-dimensional structure according to any one of claims 1 to 4, wherein an average particle diameter of the glass powder is 1 to 500 µm. Glass powder, in mass% as a _composition, which contains _{SiO 2 30~85%, Al 2 O} 3 0~30%, B 2 O 3 0~50%, the 2 O 0~10% Li 2 O + Na 2 O + K The manufacturing method of the three-dimensional molded item as described in any one of Claims 1-5 characterized by these.   The method for producing a resin composition for three-dimensional modeling according to any one of claims 1 to 6, wherein the glass powder is sintered within a softening point of the glass powder within ± 100 ° C.