JP2019112512A - Resin composition for three-dimensional molding - Google Patents

Abstract

To provide a resin composition for three-dimensional molding that makes it possible to prepare a three-dimensional molding having excellent transparency.SOLUTION: A resin composition for three-dimensional molding contains a glass filler and a curable resin. The glass filler is amorphous, and by laser diffractive scattering particle size distribution measurement, a ratio between a cumulative 10% particle size (D10) and a cumulative 90% particle size (D90), D90/D10, is 4 or less.SELECTED DRAWING: None

Description

  The present invention relates to a resin composition for three-dimensional modeling.

  Conventionally, a method of laminating a resin material or the like to obtain a three-dimensional object is known. For example, various methods such as an optical shaping method, a powder sintering method, a heat melt lamination (FDM) method have been proposed and put to practical use.

  For example, the stereolithography method is excellent in fine modeling and accurate size expression, and is widely used. This method is for producing a three-dimensional object as follows. First, a modeling stage is provided in a tank filled with a liquid photocurable resin, and the photocurable resin on the modeling stage is irradiated with an ultraviolet laser to produce a cured layer of a desired pattern. When one cured layer is formed in this manner, the shaping stage is lowered by one layer, and the uncured resin is introduced onto the cured layer, and similarly, the above-mentioned cured layer is irradiated with the ultraviolet laser to the photocurable resin. Stack a new hardened layer on top. By repeating this operation, a predetermined three-dimensional object is obtained. In the powder sintering method, a molding stage is provided in a tank filled with resin, metal, ceramic, and glass powder, and the powder on the molding stage is irradiated with a laser such as a semiconductor, and a desired pattern is obtained by softening deformation. It is for producing a hardened layer.

JP 7-26060 A

  It has been pointed out that although a three-dimensional resin-made object manufactured by an optical molding method or the like is fine and precise, it is inferior in mechanical strength and the like. Then, as proposed by patent document 1, adding an inorganic filler to photocurable resin is proposed.

  However, when inorganic filler particles are added, there is a problem that the transparency of the three-dimensional object is lost.

  An object of the present invention is to provide a resin composition for three-dimensional modeling which can produce a three-dimensional object excellent in transparency.

  The resin composition for three-dimensional shaping of the present invention is a resin composition for three-dimensional shaping containing a glass filler and a curable resin, and the glass filler is amorphous, and accumulation by laser diffraction scattering particle size distribution measurement 10 It is characterized in that the ratio D90 / D10 of the% particle diameter (D10) to the 90% accumulated particle diameter (D90) is 4 or less. A low value of D90 / D10 means that the particle size distribution is narrow (the particle size distribution is sharp and the particle size is uniform). And, the glass filler used in the present invention has a narrow particle size distribution since D90 / D10 is in a range of 4 or less, and excellent dispersibility can be obtained. That is, since it becomes possible to disperse | distribute filler powder uniformly in a resin composition, the resin composition excellent in the light transmittance can be obtained. Also, the glass filler is amorphous and substantially free of crystals in the filler. Therefore, since the interface between the glass and the crystal does not exist in the filler and light scattering due to this does not easily occur, a resin composition with high transmittance can be obtained. In addition, about an amorphous thing, it can be judged whether there is no crystallization peak using an X-ray-diffraction apparatus, for example, and only a halo peak is shown.

  In the resin composition for three-dimensional modeling of the present invention, the glass filler is preferably approximately spherical. In this way, the contact area between the glass filler and the curable resin is reduced, light scattering at the interface between the glass filler and the curable resin is suppressed, and the transparency of the shaped article can be enhanced.

The glass filler of the resin composition for three-dimensional modeling of the present invention is, in terms of mass%, SiO ₂ 20 to 70%, B ₂ O ₃ 0 to 50%, Nb ₂ O ₅ 0 to 20%, as a glass composition, WO ₃ It is preferable to contain 0 to 20%.

  The resin composition for three-dimensional modeling of the present invention preferably has a cumulative 10% particle diameter (D10) of 1 μm or more as measured by a laser diffraction / scattering particle size distribution measurement. In this way, the proportion of the glass filler having a small particle diameter decreases, so the contact area between the glass filler and the curable resin decreases, light scattering at the interface between the two is suppressed, and the transparency of the shaped object is enhanced. be able to.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the resin composition for three-dimensional modeling which can produce the three-dimensional molded article excellent in transparency.

  The resin composition for three-dimensional shaping | molding of this invention contains a glass filler and curable resin.

  The amount of the glass filler is preferably 50 to 300 parts by mass, 60 to 280 parts by mass, and particularly 70 to 260 parts by mass with respect to 100 parts by mass of the curable resin. When the amount of the glass filler is too small, the mechanical strength of the shaped article tends to be low. On the other hand, when the amount of the glass filler is too large, the viscosity of the resin composition becomes too high, the fluidity of the resin decreases, and shaping becomes difficult.

Next, the glass filler used in the present invention will be described.
(Glass filler)
The glass filler is amorphous. Therefore, light scattering in the filler is unlikely to occur, and a shaped article with high transparency is easily obtained.

  The glass filler has a ratio D90 / D10 of 10% particle diameter (D10) to 90% particle diameter (D90) by laser diffraction / scattering particle size distribution measurement is 4 or less, 3 or less, particularly 2 or less Is preferred. When D90 / D10 is too large, the particle size distribution becomes broad, and the dispersibility tends to be deteriorated. That is, since it becomes difficult to disperse the glass filler uniformly in the resin composition, it becomes difficult to obtain a shaped article with high transparency. Although the lower limit of D90 / D10 is not particularly limited, it is practically 1 or more, and further 1.1 or more.

  The preferable ranges of D10, D50 (cumulative 50% particle diameter) and D90 are as follows.

  D10 is preferably 1 to 8 μm, 2 to 8 μm, 3 to 7 μm, 4 to 7 μm, and particularly 5 to 6 μm. D50 is preferably 3 to 12 μm, 4 to 10 μm, and particularly 5 to 8 μm. D90 is preferably 5 to 16 μm, 6 to 14 μm, particularly 7 to 12 μm. If D10, D50 and D90 are too small, light scattering between the glass filler and the curable resin will increase, and it will be difficult to obtain a shaped article with high transparency. On the other hand, when D10, D50 and D90 are too large, the dispersibility tends to be deteriorated.

  The shape of the filler powder of the present invention is preferably approximately spherical. In this way, even if the particle size of the filler powder is small, the specific surface area is small, and light scattering at the interface between the filler powder and the resin can be suppressed. As a result, it becomes easy to obtain a highly transparent shaped article. The closer to a true sphere, the easier it is to obtain the above effect.

  In the glass filler, the difference in refractive index nd with the curable resin after curing is within ± 0.02 (preferably within ± 0.01, more preferably within ± 0.0075, still more preferably within ± 0.005) Preferably, the difference in Abbe number ± d is ± 10 or less (preferably ± 5.0 or less, more preferably ± 2.5 or less, still more preferably ± 1.0 or less). In addition, when the difference of the optical constant of a glass filler and curable resin becomes large, the transparency of a molded article will fall easily by inconsistencies, such as a refractive index with resin.

  The glass filler preferably has a refractive index nd of 1.40 to 1.90, 1.40 to 1.65, 1.45 to 1.6, and particularly preferably 1.5 to 1.55, and the Abbe number νd. Is preferably 20 to 65, 40 to 65, 45 to 60, particularly preferably 50 to 57. Furthermore, if the refractive index nd is 1.5 to 1.55 and the Abbe number dd is 50 to 57, the optical constant matches with many resins such as acrylic resins. If the optical constant is out of the above range, it will be difficult to obtain an optical constant matched to the curable resin after curing. The glass filler preferably has an average transmittance of 30% or more, 50% or more, particularly 70% or more, in the visible range (400 to 700 nm) at a thickness of 1 mm, from the viewpoint of enhancing the transparency of the obtained molded article. .

  It is preferable that the surface of the glass filler is treated with a silane coupling agent. When treated with a silane coupling agent, the bonding strength between the glass filler and the curable resin can be enhanced, and a shaped article having higher mechanical strength can be obtained. Furthermore, the compatibility between the glass filler and the curable resin is improved, and bubbles and voids at the interface can be reduced. As a result, light scattering can be suppressed, and the transmittance can be increased. As a silane coupling agent, an aminosilane, an epoxysilane, an acrylsilane etc. are preferable, for example. The silane coupling agent may be appropriately selected depending on the curable resin to be used.

The glass filler contains 20 to 70% of SiO ₂ , 0 to 50% of B ₂ O _3, 0 to 20% of Nb ₂ O _{5, and} 0 to 20% of WO ₃ by mass as a glass composition. Hereinafter, the reason which limited each component as mentioned above is demonstrated. In addition, in description of the content range of each component,% display means mass%.

SiO ₂ is a component that forms a glass skeleton. Further, it is a component capable of improving chemical durability and suppressing devitrification. The content of SiO ₂ is preferably 20 to 70%, 30 to 65%, particularly 40 to 60%. If the content of SiO ₂ is too small, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult. On the other hand, if the content of SiO ₂ is too large, the meltability tends to be lowered, and there is a possibility that the composition becomes difficult to soften during molding, making production difficult.

B ₂ O ₃ is a component that forms a glass skeleton. Further, it is a component capable of improving chemical durability and suppressing devitrification. The content of B ₂ O ₃ is preferably 0 to 50%, 2.5 to 40%, particularly 5 to 30%. If the content of B ₂ O ₃ is too large, the meltability is likely to be reduced, and there is a possibility that the composition becomes difficult to soften during molding, making production difficult.

Nb ₂ O ₅ is a component whose refractive index and Abbe number can be adjusted. The content of Nb ₂ O ₅ is preferably 0 to 20%, 0.1 to 15%, 0.5 to 10%, particularly 1 to 5%. If the content of Nb ₂ O ₅ is too large, the refractive index tends to be large, and the Abbe number tends to be small. Furthermore, the glass tends to be devitrified.

WO ₃ is a component that can adjust the refractive index and the Abbe number, and is a component that reduces the viscosity of the glass. The content of WO ₃ is preferably 0 to 20%, 0.1 to 15%, 0.5 to 10%, particularly 1 to 5%. If the content of WO ₃ is too large, the refractive index tends to be large and the Abbe number tends to be small. Furthermore, the glass tends to be easily colored.

  Other than the above components, for example, the following components can be introduced.

Al ₂ O ₃ is a vitrification stabilizing component. Further, it is a component capable of improving chemical durability and suppressing devitrification. The content of Al ₂ O ₃ is preferably 0 to 30%, 2.5 to 25%, particularly 5 to 20%. If the content of Al ₂ O ₃ is too large, the meltability tends to be reduced. In addition, there is a possibility that it becomes difficult to soften at the time of molding and manufacturing becomes difficult.

Li ₂ O is a component that reduces the viscosity of the glass and suppresses the devitrification. The content of Li ₂ O is preferably 0 to 10%, 0.1 to 9%, 0.5 to 7%, particularly 1 to 5%. If the content of Li ₂ O is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

Na ₂ O is a component that reduces the viscosity of the glass and suppresses the devitrification. The content of Na ₂ O is preferably 0 to 10%, 0.1 to 7.5%, 0.5 to 5%, particularly 1 to 2.5%. If the content of Na ₂ O is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

K ₂ O is a component that reduces the viscosity of the glass and suppresses the devitrification. The content of K ₂ O is preferably 0 to 10%, 0.1 to 8%, 0.5 to 6%, particularly 1 to 4%. If the content of K ₂ O is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

The total content of Li ₂ O, Na ₂ O and K ₂ O in the glass composition is preferably 10% or less, 6% or less, particularly 5% or less. If the total amount of these components is limited as described above, it is easy to suppress the evaporation of the alkali component in the glass generated at the time of resin curing. Moreover, since the fall of chemical durability can be suppressed, deterioration of resin by alkali elution can be suppressed, for example. Therefore, a colorless and transparent three-dimensional object can be easily obtained, and the deterioration of the obtained object with time can be prevented. Furthermore, since the thermal expansion coefficient of the glass can be reduced, thermal shock and thermal contraction during curing can be suppressed.

  MgO acts as an intermediate in glass and is a component that stabilizes the glass. The content of MgO is preferably 0 to 25%, 0.5 to 20%, particularly 1 to 15%. If the content of MgO is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

  CaO acts as an intermediate in glass and is a component that stabilizes glass. CaO is preferably 0 to 25%, 0.5 to 20%, and particularly preferably 1 to 15%. If the content of CaO is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

  SrO is a component that acts as an intermediate in glass and stabilizes the glass. The content of SrO is preferably 0 to 25%, 0.5 to 20%, particularly 1 to 15%. If the content of SrO is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

  BaO is a component that acts as an intermediate in glass and stabilizes the glass. The content of BaO is preferably 0 to 25%, 0.5 to 20%, particularly 1 to 15%. If the content of BaO is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

  ZnO acts as an intermediate in glass and is a component that stabilizes the glass. The content of ZnO is preferably 0 to 25%, 0.5 to 20%, particularly 1 to 15%. If the content of ZnO is too large, the chemical durability tends to be reduced, and the glass tends to be devitrified, which may make manufacturing difficult.

TiO ₂ is a component that can adjust the refractive index and the Abbe number, and is a component that reduces the viscosity of the glass. The content of TiO ₂ is preferably 0 to 15%, 0.1 to 12%, 0.5 to 10%, particularly 1 to 5%. If the content of TiO ₂ is too large, the refractive index tends to be large and the Abbe number tends to be small. Also, the glass becomes easy to color.

The total content of TiO ₂ , Nb ₂ O ₅ and WO _{3 in} the glass composition is preferably 0 to 30%, 0.1 to 25%, 1 to 20%, particularly preferably 3 to 15. If the range of these components is limited as described above, it is easy to adjust the refractive index and the Abbe number, and it becomes easy to suppress the devitrification of the glass. Furthermore, it becomes easy to obtain glass with high chemical durability.

The total content of Nb ₂ O ₅ and WO _{3 in} the glass composition is preferably 0 to 30%, 0.1 to 25%, 1 to 20%, and particularly preferably 2 to 15%. If the range of these components is limited as described above, it becomes easy to adjust the refractive index and the Abbe number, and it becomes difficult to color. Moreover, suppression of the devitrification of glass becomes easy. Furthermore, it becomes easy to obtain glass with high chemical durability.

  Next, in the case of spheroidizing the glass filler, its manufacturing method will be described.

  First, a raw material batch obtained by blending glass raw materials at a predetermined ratio is melted at 1400 to 1700 ° C. to obtain a molten glass. Next, the molten glass is formed into a predetermined shape (for example, a film), and then crushed and classified to obtain a glass powder. As a pulverization method, a ball mill, bead mill, jet mill, vibration mill or the like can be used, and wet pulverization or dry pulverization can be used. Above all, a jet mill is preferable because a powder having a narrow particle size distribution can be obtained. As a classification method, well-known classification techniques, such as a mesh sieve and an airflow classification apparatus, can be used.

  The obtained glass powder is spheroidized by heating and melting. As a heating and melting method, a method of supplying glass powder into a furnace with a table feeder etc., heating it to 1400-2000 ° C. with an air burner etc, melting it and melting it, spheroidizing glass powder by surface tension, cooling and recovering It can be mentioned.

  Next, the spheroidized glass powder is classified to have a desired particle size distribution to obtain a glass filler. As a classification method, well-known classification techniques, such as a mesh sieve and an airflow classification apparatus, can be used.

  Nanoparticles may be contained in the obtained glass filler. The nanoparticles are particles having a D50 of less than 1 μm, and can increase the viscosity of the resin composition. As a result, sedimentation of the glass filler during shaping can be suppressed. The smaller the D50 of the nanoparticles, the larger the effect of increasing the viscosity, so it is preferably 500 nm or less, 200 nm or less, 100 nm or less, 50 nm or less, 20 nm or less, particularly 10 nm or less. On the other hand, since it is difficult to produce and handle nanoparticles when D50 is too small, it is preferably 1 nm or more, particularly 2 nm or more.

  The nanoparticles include fumed silica, fumed silica aluminum, fumed titania and the like. Among them, fumed silica has a large number of silanol groups on the surface, and the fumed silicas are hydrogen-bonded to each other to form a three-dimensional network structure in the liquid resin, thereby increasing the viscosity of the resin composition. Is high.

Next, the curable resin used in the present invention will be described.
(Curable resin)
The curable resin may be any of a photocurable resin and a thermosetting resin, and can be appropriately selected according to a shaping method to be employed. For example, in the case of using an optical shaping method, a liquid photocurable resin may be selected, and in the case of employing a powder sintering method, a powdery thermosetting resin may be selected.

  Examples of the photocurable resin include polyamide resins, polyamideimide resins, polyacetal resins, (meth) acrylic resins, melamine resins, (meth) acrylic-styrene copolymers, polycarbonate resins, and styrene resins Polyvinyl chloride resin, benzoguanamine-melamine formaldehyde, silicone resin, fluorine resin, polyester resin, crosslinked (meth) acrylic resin, crosslinked polystyrene resin, crosslinked polyurethane resin, epoxy resin and the like.

  Examples of the thermosetting resin include epoxy resins, thermosetting denatured polyphenylene ether resins, thermosetting polyimide resins, urea resins, allyl resins, silicon resins, benzoxazine resins, phenol resins, Examples thereof include saturated polyester resins, bismaleimide triazine resins, alkyd resins, furan resins, melamine resins, polyurethane resins and aniline resins.

  Next, an example of a method of manufacturing a three-dimensional object will be described. Specifically, a method for producing a three-dimensional object using a resin composition containing a photocurable resin will be described. The resin composition is as described above, and the description is omitted here.

  First, a liquid layer of one layer made of a photocurable resin composition is prepared. For example, a modeling stage is provided in a tank filled with a liquid photocurable resin composition, and the upper surface of the stage is positioned to have a desired depth (for example, about 0.2 mm) from the liquid surface. By doing this, the liquid layer can be prepared on the stage.

  Next, the liquid 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. In addition to ultraviolet light, laser light such as visible light or infrared light can be used as the active energy ray.

  Subsequently, a new liquid layer made of the photocurable resin composition is prepared on the formed cured layer. For example, the photocurable resin composition can be introduced onto the cured layer by lowering the forming stage by one layer, and a new liquid layer can be prepared.

  Thereafter, the new liquid layer prepared on the hardened layer is irradiated with active energy rays to form a new hardened layer continuous with the hardened layer.

  A hardened layer is continuously laminated by repeating the above operation, and a predetermined three-dimensional object is obtained.

  EXAMPLES Hereinafter, the present invention will be described based on examples, but the present invention is not limited to these examples.

(Preparation of glass filler)
The raw material powder was prepared so as to have the composition shown in Table 1 and uniformly mixed. The obtained raw material batch was melted until it became homogeneous at 1580 to 1600 ° C., and then poured out between a pair of rollers to form a film. The refractive index of the obtained glass was measured by a refractive index measurement device (KPR-2000 manufactured by Shimadzu Corporation). Thereafter, jet milling was performed to obtain a glass powder.

  The obtained glass powder was supplied into a furnace with a table feeder, and the glass powder was heated to 1400 to 2000 ° C. with an air burner and melted to spheroidize the glass powder.

  Next, the particles adhering to the surface of the glass powder were removed by washing with water and then dried.

Next, the spheroidized glass powder was classified by an air flow classifier so as to have the particle diameter described in Table 1 to obtain a glass filler.
(Silane treatment)
In a beaker, 9 g of pure water and 1 g of a silane coupling agent (Shin-Etsu Chemical KBM-503) were mixed. Further, 0.03 g of acetic acid was added and stirred for 30 minutes using a stirrer to hydrolyze the silane coupling agent.

  Next, the first glass filler: ethanol: hydrolyzed silane coupling agent was mixed in a separate container at a weight ratio of 20: 19: 1 and stirred for 1 hour.

The alcohol was then evaporated to dryness and held at 110 ° C. for an additional 30 minutes.
(Preparation of a resin composition)
It weighed so that it might become 87 mass parts of glass fillers with respect to 100 mass parts of hardenable resin (Digital Wax company make DL360). Furthermore, the glass filler and the curable resin were mixed using a self-revolution mixer (ARE-310 manufactured by Shinky Co., Ltd.) to obtain a resin composition. The refractive index nd of the curable resin after photocuring was 1.514.
(Transmittance measurement)
An appropriate amount of the obtained resin composition was collected on a slide glass, and a glass plate of 0.5 mm in thickness was sandwiched by another slide glass as a spacer, and the resin composition was cured by irradiation with ultraviolet light.

  Next, the total light transmittance of the resin composition including the slide glass was measured by a spectrophotometer (UV-3100 manufactured by Shimadzu Corporation), and the transmittance at 588 nm was measured.

  As shown in Table 1, Examples 1 and 2 had a high transmittance of 82%. On the other hand, in Comparative Example 3, the light transmittance was as low as 46% because D90 / D10 was as large as 4.1 and the particle size distribution was broad.

Claims (4)

  A resin composition for three-dimensional shaping comprising a glass filler and a curable resin, wherein the glass filler is amorphous, and a cumulative 10% particle diameter (D10) and a cumulative 90% particle by laser diffraction scattering type particle size distribution measurement The resin composition for three-dimensional model | molding characterized by ratio D90 / D10 with a diameter (D90) being four or less.   The resin composition for three-dimensional modeling according to claim 1, wherein the glass filler is substantially spherical. The glass filler is characterized by containing, as a glass composition, 20 to 70% of SiO ₂ , 0 to 50% of B ₂ O _3, 0 to 20% of Nb ₂ O _{5, and} 0 to 20% of WO ₃ by mass%. The resin composition for three-dimensional modeling according to claim 1 or 2.   The resin composition for three-dimensional modeling according to any one of claims 1 to 3, wherein a cumulative 10% particle diameter (D10) determined by laser diffraction / scattering particle size distribution measurement is 1 μm or more.