JP2022071004A - Resin powder for three-dimensional molding, manufacturing method of three-dimensional molding, and manufacturing apparatus for three-dimensional molding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin powder for three-dimensional molding that has excellent density, dimensional stability, and surface properties of the resulting three-dimensional object, even when stored in a high humidity environment, and that prevents loss of strength.

SOLUTION: A resin powder for three-dimensional molding has an average equivalent diameter of between 10 μm and 150 μm on a piece count basis, a median of a particle size distribution of an equivalent diameter is larger than the average equivalent diameter, and a loose fill ratio is 40.4% or more.

SELECTED DRAWING: None

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to a resin powder for three-dimensional modeling, a method for producing a three-dimensional model, and an apparatus for producing a three-dimensional model.

The powder additive manufacturing method is a method of forming a powdered material by solidifying it layer by layer using a laser or a binder.

The method using a laser is called a powder bed fusion (PBF) method, and for example, an SLS (selective laser sintering) method for selectively irradiating a laser to form a three-dimensional object or a mask is used. An SMS (selective mask sintering) method in which a laser is applied in a plane is known. On the other hand, as a method using the binder, for example, a binder jet method for forming a three-dimensional model by ejecting ink containing a binder resin by a method such as inkjet is known.

Among these, in the PBF method, the powder is melt-bonded by selectively irradiating a thin layer of metal, ceramics, or resin with a laser beam to melt and bond the powder, and then another film is formed on the film. By forming layers and repeating the same operation, three-dimensional shaped objects can be obtained by sequentially laminating them (see, for example, Patent Documents 1 to 4).

When the PBF method resin powder is used, the layer of the resin powder supplied to the supply tank is heated to a temperature near the softening point of the resin while maintaining and relaxing the internal stress between the thin layers. Then, this layer is selectively irradiated with a laser beam, and the irradiated resin powder itself is heated to a temperature above the softening point and fused to each other to perform three-dimensional modeling.

Currently, a large amount of polyamide resin is used in the PBF method, and in particular, polyamide 12 can be suitably used because it has a relatively low melting point among polyamides, has a low heat shrinkage rate, and has low water absorption.
In recent years, there has been an increase in demand for using shaped objects as final products in addition to prototype applications, and there is an increasing demand for the use of various resins.

The present invention provides a resin powder for three-dimensional modeling which is excellent in density, dimensional stability, and surface properties of the three-dimensional model obtained even when stored in a high humidity environment and can prevent a decrease in strength. The purpose.

The resin powder for three-dimensional modeling of the present invention as a means for solving the above-mentioned problems has an average circle-equivalent diameter of 10 μm or more and 150 μm or less based on the number, and the median particle size distribution of the circle-equivalent diameter is the average circle. Larger than the equivalent diameter.

According to the present invention, there is provided a resin powder for three-dimensional modeling which is excellent in density, dimensional stability and surface properties of the three-dimensional model obtained even when stored in a high humidity environment and can prevent a decrease in strength.

FIG. 1 is a schematic diagram showing an example of a substantially cylindrical body. FIG. 2 is a schematic explanatory view showing an example of an apparatus for manufacturing a three-dimensional model used in the method for manufacturing a three-dimensional model of the present invention. FIG. 3A is a schematic view showing an example of a step of forming a powder layer having a smooth surface. FIG. 3B is a schematic view showing an example of a step of forming a powder layer having a smooth surface. FIG. 3C is a schematic view showing an example of a process of dropping a liquid material for three-dimensional modeling. FIG. 3D is a schematic view showing an example of a process in which a resin powder layer is newly formed in a modeling powder storage tank. FIG. 3E is a schematic view showing an example of a process in which a resin powder layer is newly formed in the modeling powder storage tank. FIG. 3F is a schematic view showing an example of a process of dropping the liquid material for three-dimensional modeling again. FIG. 4 is a diagram showing the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Example 1. FIG. 5 is a diagram showing the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Comparative Example 1. FIG. 6 is a diagram showing the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Comparative Example 2.

(Resin powder for 3D modeling)
The resin powder for three-dimensional modeling of the present invention has an average circle-equivalent diameter of 10 μm or more and 150 μm or less on a number basis, a median particle size distribution of the circle-equivalent diameter is larger than the average circle-equivalent diameter, and contains a thermoplastic resin. It is preferable, and further contains other components as needed.
The resin powder for three-dimensional modeling of the present invention is based on the finding that the conventional resin powder for three-dimensional modeling has a problem that the strength of the obtained three-dimensional model is reduced due to the influence of humidity in the storage environment. ..

Since the fine powder has a large specific surface area per volume, the contact points and contact areas between the particles are larger than those of the coarse particles. In a high temperature and high humidity environment, a liquid cross-linking force by water acts on the contact points between particles, and the fluidity of the powder is lowered, but the fluidity of the fine powder is greatly lowered due to the size of the contact point and the contact area. This decrease in fluidity is manifested in a decrease in the bulk density of the powder. The decrease in the bulk density of the powder leads to a decrease in the density of the modeled object after modeling with the modeling device and a decrease in the strength. On the other hand, the resin powder for three-dimensional modeling of the present invention suppresses the influence of the liquid cross-linking force by water on the contact points between particles in a high temperature and high humidity environment, and prevents the powder from decreasing in fluidity. It is possible to suppress a decrease in the bulk density of the resin powder for three-dimensional modeling, thereby improving the density and strength of the modeled object after modeling.

[Diameter equivalent to average circle]
The average circle-equivalent diameter (average value of the particle size distribution of the circle-equivalent diameter) is 10 μm or more and 150 μm or less, preferably 20 μm or more and 90 μm or less, and more preferably 35 μm or more and 60 μm or less. When the average circle equivalent diameter is 10 μm or more and 150 μm or less, the density, dimensional stability, and surface properties of the obtained three-dimensional model are excellent and the strength is lowered even when stored in a high humidity environment. Can be prevented. The average circle-equivalent diameter can be measured using, for example, a particle image analyzer (device name: FPIA3000, manufactured by Spectris) or the like.

The diameter equivalent to a circle can be calculated by the following formula.
Circle equivalent diameter = Positive square root of {4 × (area) ÷ π} The circle equivalent diameter is calculated for the projection drawing of each particle. The average value of the obtained circle-equivalent diameters (number-based) can be calculated to calculate the average circle-equivalent diameter.

[Median value of particle size distribution of circle equivalent diameter and average value of particle size distribution of circle equivalent diameter]
As the resin powder for three-dimensional modeling, the sizes of the main particles constituting the powder are gathered within 30 μm or more and 90 μm or less in the powder having a small amount of fine mixture, and the average value is in the above range.
The median value of the particle size distribution having the equivalent circle diameter is preferably larger than the average equivalent circle diameter (the average value of the particle size distribution having the equivalent circle diameter). When the median value is larger than the average circle equivalent diameter, the density, dimensional stability, and surface properties of the obtained three-dimensional model are excellent and the strength can be prevented from decreasing even when stored in a high humidity environment.
In the particle size distribution of the circle equivalent diameter, when the skirting covers a wide range with respect to the mountain where the particle size distribution is concentrated, the median value is close to the mountain, and the average circle equivalent diameter is affected by the skirting. It is located far from the median because it receives a large amount. That is, when the median value is larger than the average circle equivalent diameter, it means that the mountain where the main particle size distribution is concentrated is in a large position, and the fine powder does not form the main mountain. On the other hand, when the median value is smaller than the average circle equivalent diameter, it indicates that the main peaks are formed of fine powder. This provides an index as to which of the fine powder and the resin powder particles occupies the main part in the number distribution. For the median particle size distribution of the equivalent circle diameter, use a wet flow type particle size / shape analyzer (device name: FPIA-3000, manufactured by Sysmex Co., Ltd.), and the number of powder particle counts is 3,000 or more. It is possible to acquire a particle shape image, measure the equivalent circle diameter of particles having a particle diameter of 0.5 μm or more and 200 μm or less, obtain the particle size distribution, and calculate the median value from the particle size distribution. can.

[Average circularity]
The average circularity is preferably 0.75 or more and 0.90 or less, and more preferably 0.75 or more and 0.85 or less. When the average circularity is 0.75 or more and 0.90 or less, the three-dimensional model obtained is excellent in density, dimensional stability, and surface properties even when stored in a high humidity environment, and has strength. It can prevent the decrease.
The circularity is an index showing the roundness, and 1 means that it is the closest to a circle. The circularity is obtained by the following formula when the area (number of pixels) is S and the peripheral length is L.
Circularity = 4πS / L ²
As the average circularity, the circularity of the resin powder for three-dimensional modeling is measured, and an arithmetically averaged value thereof can be used.
As a method for simply determining the circularity, for example, it can be quantified by measuring using a wet flow type particle size / shape analyzer (device name: FPIA-3000, manufactured by Sysmex Corporation). .. The wet flow type particle size / shape analyzer can take a high-speed image of particles in a suspension flowing in a glass cell with a CCD and analyze individual particle images in real time, and photographs such particles. However, an apparatus that performs image analysis is effective in determining the average circularity of the present invention. The number of measurement counts of the particles is not particularly limited, but is preferably 1,000 or more, and more preferably 3,000 or more.

[Loose filling rate]
The loose filling factor is the loose bulk density measured using a bulk density meter (compatible with JIS Z-2504, manufactured by Kuramochi Kagaku Kikai Seisakusho Co., Ltd.) divided by the true density of the resin.
The loose filling rate is preferably 20% or more and 50% or less, and more preferably 30% or more and 40% or less. The loose filling factor is calculated by measuring the loose density using a bulk hydrometer (JIS Z-2504 compatible, manufactured by Kuramochi Kagaku Kikai Seisakusho Co., Ltd.) and dividing the obtained loose density by the true density of the resin. can do.

The resin powder for three-dimensional modeling is preferably prism-shaped particles.
The columnar particles are not particularly limited and may be appropriately selected depending on the intended purpose, but the columnar length is preferably 10 μm or more and 150 μm or less, and the columnar diameter is 10 μm or more and 150 μm or less. preferable.

<Thermoplastic resin>
The thermoplastic resin means a resin that is plasticized and melted when heated.
Examples of the thermoplastic resin include crystalline resins. The crystalline resin means a resin having a melting peak when measured by ISO 3146 (plastic transition temperature measuring method, JIS K7121).
The crystalline resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, polyolefin, polyamide, polyester, polyether, polyphenylene sulfide, liquid crystal polymer (LCP), polyacetal (POM), polyimide, etc. A polymer such as a fluororesin is preferably used. These may be used alone or in combination of two or more.

Examples of the polyolefin include polyethylene and polypropylene. These may be used alone or in combination of two or more.

Examples of the polyamide include polyamide 410 (PA410), polyamide 6 (PA6), polyamide 66 (PA66), polyamide 610 (PA610), polyamide 612 (PA612), polyamide 11 (PA11), polyamide 12 (PA12); Examples thereof include aromatic polyamide 4T (PA4T), polyamide MXD6 (PAMXD6), polyamide 6T (PA6T), polyamide 9T (PA9T), and polyamide 10T (PA10T). These may be used alone or in combination of two or more. Among these, PA9T is also called polynonamethylene terephthalamide, and is called semi-aromatic because carbon is composed of 9 diamines and a terephthalic acid monomer, and the carboxylic acid side is generally aromatic. Further, the polyamide of the present invention also includes what is called aramid, which is composed of p-phenylenediamine and a terephthalic acid monomer as a total aromatic whose diamine side is also aromatic.

Examples of the polyester include polyethylene terephthalate (PET), polybutadiene terephthalate (PBT), polylactic acid (PLA) and the like. Polyesters containing aromatics partially containing terephthalic acid or isophthalic acid can also be suitably used in the present invention in order to impart heat resistance.

Examples of the polyether include polyetheretherketone (PEEK), polyetherketone (PEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), polyetheretherketoneketone (PEEKK), and polyether. Examples thereof include ketone ether ketone ketone (PEKEKK).
In addition to the above-mentioned polyether, a crystalline polymer may be used, and examples thereof include polyacetal, polyimide, and polyether sulfone. A plastic having two melting point peaks such as PA9T may be used (the resin temperature needs to be raised above the second melting point peak in order to completely melt).

In addition to the thermoplastic resin, the resin powder for three-dimensional modeling includes a resin powder made of a non-crystalline resin, a reinforcing agent, a flame retardant, a plasticizer, a stabilizer, an antioxidant, a crystal nucleating agent, and the like. It may contain additives and the like. These may be used alone or in combination of two or more. These may be mixed with the thermoplastic resin and embedded in the resin powder for three-dimensional modeling, or may be adhered to the surface of the resin powder for three-dimensional modeling.

The fortifier is mainly added to increase the strength and is contained as a filler or a filler. For example, glass fillers, glass beads, carbon fibers, aluminum balls, and those described in International Publication No. 2008/057444 pamphlet can be mentioned. These may be used alone, may be used in combination of two or more, or may be contained in the resin. The resin powder of the present invention is preferably appropriately dried, and may be dried before use by adding a vacuum dryer or silica gel.

Examples of the antioxidant include hydrazide-based and amide-based metal inactivating agents, phenol-based (hindered-phenol-based) and amine-based radical trapping agents, and phosphate-based and sulfur-based peroxide decomposing agents. Examples include radicals and triazines, which are ultraviolet absorbers. These may be used alone or in combination of two or more. In particular, it is known that it is effective when a radical scavenger and a peroxide decomposing agent are used in combination, and it is also particularly effective in the present invention.

The content of the antioxidant is preferably 0.05% by mass or more and 5% by mass or less, more preferably 0.1% by mass or more and 3% by mass or less, and 0.2. It is particularly preferable to use% by mass or more and 2% by mass or less. When the content is within the above range, the effect of preventing thermal deterioration can be obtained, and the resin powder for three-dimensional modeling used for modeling can be reused. In addition, the effect of preventing discoloration due to heat can also be obtained.

The resin powder for three-dimensional modeling is preferably a resin having a melting point of 100 ° C. or higher as measured in accordance with ISO 3146. It is preferable that the melting point of 100 ° C. or higher as measured in accordance with ISO 3146 is within the heat resistant temperature range that can be used for the exterior of the product. The melting point can be measured by using differential scanning calorimetry (DSC) in accordance with ISO 3146 (Plastic transition temperature measuring method, JIS K7121), and if there are multiple melting points, the high temperature side. Use the melting point of.

As the crystalline resin, a crystal-controlled crystalline thermoplastic resin is preferable. The crystalline thermoplastic resin can be obtained by, for example, a conventionally known method of external stimulation such as heat treatment, stretching, crystal nucleating agent, and ultrasonic treatment. As described above, the crystalline thermoplastic resin in which the crystal size and the crystal orientation are controlled is more preferable because it can reduce the error generated at the time of recoating at a high temperature.

The method for producing the crystalline thermoplastic resin is not particularly limited and may be appropriately selected depending on the intended purpose. For example, the powder is heated at a temperature equal to or higher than the glass transition temperature of each resin to obtain crystallinity. A method of enhancing the annealing treatment or adding a crystal nucleating agent in order to further enhance the crystallinity and then performing an annealing treatment can be used. In addition, a method of increasing crystallinity by sonication or dissolving in a solvent and slowly volatilizing, a method of growing crystals by an external electric field application treatment, and a method of further stretching to crush and cut a highly oriented and highly crystallized product. Examples thereof include a method of performing processing such as.

The annealing treatment can be performed, for example, by heating the resin at a temperature 50 ° C. higher than the glass transition temperature for 3 days, and then slowly cooling the resin to room temperature.

The stretching is, for example, a method of stretching the resin melt in a fibrous form while stirring at a temperature higher than the melting point by 30 ° C. or more using an extrusion processing machine. Specifically, the melt is stretched 1 to 10 times or less to form fibers. The larger the number of nozzle mouths, the higher the productivity can be expected. For the early stretching, the maximum stretching ratio can be changed for each resin and melt viscosity.

Regarding the ultrasonic treatment, for example, glycerin (manufactured by Tokyo Kasei Kogyo Co., Ltd., reagent grade) solvent is added to the resin about 5 times, and then heated to a temperature 20 ° C. higher than the melting point to generate ultrasonic waves. It can be performed by applying ultrasonic waves at 24 kHz and an amplitude of 60% for 2 hours with an apparatus (ultrasonicator UP200S manufactured by Heelshire Co., Ltd.). Then, it is preferable to wash with an isopropanol solvent at room temperature and then vacuum dry.

The external electric field application treatment can be performed, for example, by heating the resin powder at a glass transition temperature or higher, applying an AC electric field (500 hertz) of 600 V / cm for 1 hour, and slowly cooling the resin powder.

Among the powder laminating methods, the PBF method is very effective when the temperature width (temperature window) for the change in the crystal layer is large because the warp can be suppressed and the molding stability is improved. For that purpose, it is preferable to use a resin powder having a larger difference between the melting start temperature and the recrystallization temperature at the time of cooling, and the crystalline thermoplastic resin is particularly preferably used.

The crystalline thermoplastic resin can be identified by satisfying at least one selected from the following (1) to (3), for example.
(1) In the differential scanning calorimetry, the melting start temperature of the endothermic peak when the temperature is raised to a temperature 30 ° C. higher than the melting point at 10 ° C./min is set to Tmf1 in accordance with ISO 3146, and then 10 ° C./min. When the temperature is lowered to -30 ° C or lower at min and further raised to a temperature 30 ° C higher than the melting point at 10 ° C / min, the melting start temperature of the endothermic peak is Tmf2, and Tmf1> Tmf2. Become. The melting start temperature of the endothermic peak is when a straight line parallel to the x-axis is drawn from a place where the amount of heat is constant to the low temperature side after the endothermic heat is finished, and the temperature drops by -15 mW from the straight line. The temperature at.

(2) In the differential scanning calorimetry, the crystallinity obtained from the energy amount of the endothermic peak when the temperature is raised to a temperature 30 ° C. higher than the melting point at 10 ° C./min in accordance with ISO 3146 is defined as Cd1. After that, the crystallinity obtained from the energy amount of the endothermic peak when the temperature is lowered to -30 ° C or lower at 10 ° C / min and further raised to a temperature 30 ° C higher than the melting point at 10 ° C / min. When Cd2 is set, Cd1> Cd2.

(3) The degree of crystallization obtained by X-ray diffraction measurement is Cx1, the temperature is raised to a temperature 30 ° C. higher than the melting point at 10 ° C./min under a nitrogen atmosphere, and then at 10 ° C./min, −30 ° C. Cx1> Cx2 when the degree of crystallization obtained by the X-ray diffraction measurement when the temperature is lowered to the following and further raised to a temperature 30 ° C. higher than the melting point at 10 ° C./min is Cx2.

The above (1) to (3) define the characteristics of the same resin powder from different viewpoints, and the above (1) to (3) are related to each other, and the above (1) to (3). ), It is effective if any one of them can be satisfied. The above (1) to (3) can be measured by, for example, the following method.

[Measurement method of melting start temperature by differential scanning calorimetry under condition (1)]
The method for measuring the melting start temperature by the differential scanning calorimetry (DSC) under the condition (1) is based on the measurement method of ISO 3146 (plastic transition temperature measuring method, JIS K7121), and is a differential scanning calorimetry device (Co., Ltd.). Using DSC-60A) manufactured by Shimadzu Corporation, the melting start temperature (Tmf1) of the heat absorption peak when the temperature is raised to a temperature 30 ° C. higher than the melting point at 10 ° C./min is measured. After that, the temperature is lowered to −30 ° C. or lower at 10 ° C./min, and the melting start temperature (Tmf2) of the endothermic peak is measured at 10 ° C./min when the temperature is raised to a temperature 30 ° C. higher than the melting point. .. The melting start temperature of the endothermic peak is when a straight line parallel to the x-axis is drawn from a place where the amount of heat is constant to the low temperature side after the endothermic heat is finished, and the temperature drops by -15 mW from the straight line. The temperature at.

[Method of measuring crystallinity by differential scanning calorimetry under condition (2)]
The method for measuring the degree of crystallization by differential scanning calorimetry (DSC) under the condition (2) is based on ISO 3146 (plastic transition temperature measuring method, JISK7121) at 10 ° C./min and 30 ° C. from the melting point. The energy amount (heat of fusion) of the heat absorption peak when the temperature is raised to a high temperature can be measured, and the degree of crystallization (Cd1) can be obtained from the amount of heat of fusion with respect to the complete crystal heat amount. After that, the temperature was lowered to -30 ° C or lower at 10 ° C / min, and the energy amount of the heat absorption peak when the temperature was further raised to a temperature 30 ° C higher than the melting point at 10 ° C / min was measured, and the perfect crystal calorific value was measured. The crystallinity (Cd2) can be obtained from the amount of heat of fusion with respect to.

[Measurement method of crystallinity by X-ray analyzer of condition (3)]
As a method for measuring the crystallinity by the X-ray analyzer of the above condition (3), an X-ray analyzer (Bruker, Discover8) having a two-dimensional detector is used, and the 2θ range is set to 10 to 40 at room temperature. The powder can be set and the obtained powder can be placed on a glass plate and the crystallinity can be measured (Cx1). Next, in the DSC, the sample was heated at 10 ° C./min under a nitrogen atmosphere, heated to a temperature 30 ° C. higher than the melting point, kept warm for 10 minutes, and then cooled to 10 ° C./min and -30 ° C. Can be returned to room temperature and the crystallinity (Cx2) can be measured in the same manner as Cx1.

Further, as the resin powder for three-dimensional modeling, the SLS method and the SMS method can be used, but such as appropriate particle size, particle size distribution, heat transfer characteristics, melt viscosity, bulk density, fluidity, melt temperature, and recrystallization temperature. It exhibits the characteristics that show an appropriate balance for various parameters.

Regarding the bulk density of the resin powder for three-dimensional modeling, there is a difference in the density of the resin itself from the viewpoint of promoting the degree of laser sintering in the PBF method, but it is preferable that the bulk density is large, and the tap density is 0. .35 g / mL or more is more preferable, 0.40 g / mL or more is further preferable, and 0.5 g / mL or more is particularly preferable.

Using the resin powder for three-dimensional modeling, the three-dimensional model formed by laser sintering is smooth and can form a surface exhibiting a minimum orange peel or less and exhibiting sufficient resolution. Here, the orange peel means the presence of an improper rough surface or surface defects such as holes and distortions on the surface of a three-dimensional model generally formed by laser sintering in PBF. The holes may not only spoil the aesthetics, but may also significantly affect the mechanical strength, for example.

Further, the three-dimensional model formed by laser sintering using the resin powder for three-dimensional modeling may be warped, distorted, or smoked due to the phase change generated during the period from sintering to cooling after sintering. It is preferable not to show such inappropriate process characteristics.

By using the resin powder for three-dimensional modeling of the present invention, it is possible to obtain a three-dimensional model having high dimensional accuracy and strength and excellent surface properties (orange peeling property). Further, it is excellent in recyclability, and even if the surplus powder is repeatedly used, it is possible to suppress a decrease in dimensional accuracy and strength of the three-dimensional model.

[Manufacturing method of particles]
As the resin powder for three-dimensional modeling of the present invention, a method of fiberizing a resin and then cutting it to directly obtain substantially prismatic particles (substantially cylindrical or polygonal prism), or obtaining a similar prism from a film shape. A method or a method of producing a substantially cylindrical body by post-processing after producing the obtained particles of the polygonal prism may be used.

-Approximately columnar particles-
The resin powder for three-dimensional modeling of the present invention preferably contains substantially prismatic particles. The substantially prismatic particles are particles having a columnar or tubular shape having a bottom surface and an upper surface, and the shape of the bottom surface or the upper surface such as a substantially cylindrical body or a polygonal prism is not particularly limited, depending on the purpose. Can be selected as appropriate. If the shape of the bottom surface or the top surface is a circle or an ellipse, it is a substantially cylindrical body (FIG. 1), and if it is a polygon such as a quadrangle or a hexagon, it is a polygonal column. The shapes of the bottom surface and the top surface may be the same or different as long as they have a columnar or cylindrical region between the bottom surface and the top surface. Further, it may be a straight pillar body in which the bottom surface or the upper surface and the portion (side surface) of the pillar are orthogonal to each other, or an oblique pillar body which is not orthogonal to each other.

Since the shape of the resin powder is substantially a prism, it is possible to obtain a powder having a small angle of repose and high powder surface smoothness at the time of recoating. As a result, the surface property of the obtained three-dimensional model can be improved. From the viewpoint of productivity and modeling stability, it is more preferable that the bottom surface and the top surface are substantially parallel to each other and are close to a straight column. The shape of the substantially columnar body is, for example, a scanning electron microscope (device name: S4200, manufactured by Hitachi, Ltd.), a wet flow type particle size / shape analyzer (device name: FPIA-3000, manufactured by Sysmex Co., Ltd.). ) Etc., and can be discriminated by observing.

The content of the substantially prismatic particles is preferably 50% or more, more preferably 75% or more, and particularly preferably 90% or more, based on the total amount of the resin powder for three-dimensional modeling. When the content of the substantially prismatic particles is 50% or more, the effect of increasing the packing density is remarkably exhibited, and it is very effective in improving the dimensional accuracy and strength of the obtained three-dimensional model.

-Approximately cylindrical body-
The substantially cylindrical body is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include a true columnar body and an elliptical columnar body. Of these, the one closer to a true cylinder is more preferable. The substantially circle of the substantially cylindrical body means that the ratio of the major axis to the minor axis (major axis / minor axis) is 1 to 10, and includes those in which a part of the circular portion is missing.
It is preferable that the substantially cylindrical body has surfaces facing each other in substantially circles. The size of the circles on the facing surfaces may be different, but the ratio of the diameters of the circles (large surface / small surface) between the large surface and the small surface is effective in increasing the density. It is preferably 5.5 times or less, and more preferably 1.1 times or less.

The long side of the bottom surface of the substantially cylindrical body is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 μm or more and 200 μm or less. The long side of the bottom surface of the substantially cylindrical particles represents the diameter of the bottom surface. When the circular part of the substantially cylindrical particle is elliptical, it means the major axis. The height (distance between the bottom surface and the top surface) of the substantially cylindrical body is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 5 μm or more and 200 μm or less. When the long side of the bottom surface is within the range, the winding of the resin powder can be reduced when the powder layer is formed, the surface of the powder layer becomes smooth, and the voids formed between the resin powders can be reduced. , The effect of further improving the surface property and dimensional accuracy of the three-dimensional model can be obtained.
The long side and height of the bottom surface of the particles may be less than 5 μm or more than 200 μm, but the smaller the number is preferable. Specifically, the particles having the long side and the height of the bottom surface of 5 μm or more and 200 μm or less are preferably 50% or more, more preferably 75% or more with respect to all the particles.

Examples of the method of fiberization include a method of stretching the resin melt in a fibrous form while stirring at a temperature higher than the melting point by 30 ° C. or more by using an extrusion processing machine. At this time, it is preferable that the resin melt is stretched 1 to 10 times or less to become fibrous. In this case, the shape of the bottom surface of the column is determined by the shape of the nozzle hole of the extruder. For example, when the shape of the bottom surface of the pillar, that is, the cross section of the fiber is circular, the nozzle hole is also circular, and when it is polygonal, the nozzle hole is also selected accordingly. The higher the dimensional accuracy of the three-dimensional model, the better. It is preferable to increase the number of nozzle openings as much as possible in order to increase productivity.

As a method of cutting the fiber, a cutting device in which both the upper and lower blades of the guillotine method are blades, and a device called a push-cutting method in which the lower side is cut with a plate instead of a blade and with the upper blade. And so on, these conventionally known devices can be used. The conventionally known apparatus is preferably used because, for example, there is an apparatus that directly cuts to 0.005 mm or more and 0.2 mm or less, and a method that can cut using a CO ₂ laser or the like. By these methods, the resin powder for three-dimensional modeling of the present invention can be obtained.

The method of crushing the resin pellets is also effectively used. For example, it can be obtained by mechanically pulverizing a resin in the form of pellets or the like using a conventionally known pulverizer, and classifying the obtained resin powder into a resin having a particle size other than the desired particle size. The temperature at the time of pulverization is preferably 0 ° C. or lower (fragile temperature or less of each resin itself), more preferably -25 ° C. or lower, and particularly preferably -100 ° C. or lower, which is effective because the pulverization efficiency is improved. ..

The resin powder for three-dimensional modeling of the present invention is used to form a three-dimensional product using a laser sintering method based on the PBF method, for example, an SLS (selective laser sintering) method or an SMS (selective mask sintering) method. It is useful.

(Manufacturing method of three-dimensional model and equipment for manufacturing three-dimensional model)
The method for producing a three-dimensional model of the present invention comprises a layer forming step of forming a layer made of the resin powder for three-dimensional modeling of the present invention, and electromagnetically irradiating a selected region of the formed layer to bond the resin powders to each other. The powder bonding step is repeated, and if necessary, other steps are included.
The apparatus for producing a three-dimensional model includes a layer forming means for forming a layer made of the resin powder of the present invention, and a powder bonding means for adhering the resin powders for three-dimensional modeling in a selected region of the layer. And, if necessary, include other means.
The method for manufacturing the three-dimensional model can be suitably carried out by using the apparatus for manufacturing the three-dimensional model. As the resin powder for three-dimensional modeling, the same resin powder for three-dimensional modeling of the present invention can be used.

The resin powder for three-dimensional modeling can be used and is effective for all the three-dimensional modeling object manufacturing devices of the powder laminating method. The powder laminating type three-dimensional model manufacturing equipment has different means for adhering the resin powders in the selected region after forming the powder layer, and generally has an electromagnetic irradiation means typified by the SLS method or the SMS method and a binder. Examples thereof include a liquid discharge means represented by a jet method. The resin powder for three-dimensional modeling of the present invention can be applied to any of these, and is effective for all three-dimensional modeling devices including means for laminating powders.

The powder bonding means is not particularly limited and may be appropriately selected depending on the intended purpose. Examples thereof include means for irradiating electromagnetic waves.

In the manufacturing equipment for three-dimensional objects such as the SLS method and the SMS method that use the irradiation of electromagnetic waves, the electromagnetic wave irradiation source used for the irradiation of electromagnetic waves includes, for example, a laser that irradiates ultraviolet rays, visible rays, infrared rays, and the like, as well as microwaves. Examples include waves, discharges, electron beams, radiant heaters, LED lamps, etc., or combinations thereof.
Further, when electromagnetic wave irradiation is used as a method for selectively adhering the three-dimensional modeling resin powder, there is also a method of efficiently absorbing or hindering the absorption. For example, an absorbent or an inhibitor is used as the resin. It is also possible to add it to the powder.

An example of an apparatus for manufacturing these three-dimensional objects will be described with reference to FIG. FIG. 2 is a schematic view showing an example of a three-dimensional model manufacturing apparatus. As shown in FIG. 2, the powder is stored in the powder supply tank 5, and is supplied to the laser scanning space 6 by using a roller 4 according to the amount used. It is preferable that the temperature of the supply tank 5 is controlled by the heater 3. The laser output from the electromagnetic irradiation source 1 is irradiated to the laser scanning space 6 using the reflecting mirror 2. The heat from the laser can be used to sinter the powder to obtain a three-dimensional model.

The temperature of the supply tank 5 is preferably 10 ° C. or higher lower than the melting point of the powder.
The component floor temperature in the laser scanning space is preferably 5 ° C. or higher lower than the melting point of the powder.
The laser output is not particularly limited and may be appropriately selected depending on the intended purpose, but is preferably 10 watts or more and 150 watts or less.

In another embodiment, the selective mask sintering (SMS) technique can be used to produce the three-dimensional model of the present invention. As the SMS process, for example, the one described in US Pat. No. 6,531,086 can be preferably used.

In the SMS process, a shielding mask is used to selectively block infrared radiation and selectively irradiate a part of the powder layer. When the SMS process is used to produce a three-dimensional model from the resin powder for three-dimensional modeling of the present invention, it is possible and effective to contain a material that enhances the infrared absorption characteristics of the resin powder. For example, the resin powder can contain one or more heat absorbers and / or dark-colored substances (carbon fiber, carbon black, carbon nanotube, carbon fiber, cellulose nanofiber, etc.).

In still another embodiment, the resin powder for three-dimensional modeling of the present invention can be used to produce a three-dimensional model using the binder jet type three-dimensional modeling device described above. This method comprises a layer forming step of forming a layer made of the resin powder for three-dimensional modeling of the present invention, and a powder bonding step of discharging a liquid into a selected region of the formed layer and drying the resin powder to bond the resin powders to each other. And, are repeated, and other steps are included as necessary.

The three-dimensional object manufacturing apparatus has a layer forming means for forming a layer made of the resin powder for three-dimensional modeling of the present invention, and a means for discharging a liquid into a selected region of the formed layer. Further, if necessary, other means are included. As the means for discharging the liquid, it is preferable to use an inkjet method from the viewpoint of dimensional accuracy and modeling speed of the obtained three-dimensional model.

FIG. 3 shows an example of a schematic process diagram of the binder jet method. The three-dimensional model manufacturing apparatus shown in FIG. 3 has a powder storage tank 11 for modeling and a powder storage tank 12 for supply, and each of these powder storage tanks has a stage 13 that can be moved up and down. The resin powder of the present invention is placed on the stage 13 to form a layer made of the resin powder for three-dimensional modeling. Above the modeling powder storage tank 11, a three-dimensional modeling liquid material supply means 15 for discharging the three-dimensional modeling liquid material 16 toward the three-dimensional modeling resin powder in the powder storage tank is provided, and further supplied. Resin powder layer forming means 14 (which can supply the resin powder for three-dimensional modeling from the powder storage tank 12 for modeling to the powder storage tank 11 for modeling and smooth the surface of the resin powder (layer) of the powder storage tank 11 for modeling. Hereinafter, it also has a leveling mechanism and a recorder).

3A and 3B show a step of supplying resin powder from the supply powder storage tank 12 to the modeling powder storage tank 11 and forming a resin powder layer having a smooth surface. Each stage 13 of the powder storage tank 11 for modeling and the powder storage tank 12 for supply is controlled, the gap is adjusted so as to have a desired layer thickness, and the resin powder layer forming means 14 is modeled from the powder storage tank 12 for supply. By moving to the powder storage tank 11 for modeling, a resin powder layer is formed in the powder storage tank 11 for modeling.

FIG. 3C shows a step of dropping the three-dimensional modeling liquid material 16 onto the resin powder layer of the modeling powder storage tank 11 by using the three-dimensional modeling liquid material supply means 15. At this time, the position where the liquid material 16 for three-dimensional modeling is dropped onto the resin powder layer is determined by the two-dimensional image data (slice data) obtained by slicing the three-dimensional model into a number of planes.

3D and E show that the stage 13 of the supply powder storage tank 12 is raised, the stage 13 of the modeling powder storage tank 11 is lowered, the gap is controlled so as to have a desired layer thickness, and the resin powder layer is again formed. By moving the forming means 14 from the supply powder storage tank 12 to the modeling powder storage tank 11, a new resin powder layer is formed in the modeling powder storage tank 11.

FIG. 3F is a step of dropping the three-dimensional modeling liquid material 16 onto the resin powder layer of the modeling powder storage tank 11 again by using the three-dimensional modeling liquid material supply means 15. By repeating these series of steps and drying as necessary to remove the resin powder (surplus powder) to which the liquid material for three-dimensional modeling is not attached, the three-dimensional model can be obtained.

In order to bond the resin powders to each other, it is preferable to include an adhesive. The adhesive may be contained in a state of being dissolved in the liquid to be discharged, or may be mixed as adhesive particles in the resin powder of the previous term. The adhesive is preferably dissolved in the liquid to be discharged. For example, if the liquid to be discharged is mainly composed of water, the adhesive is preferably water-soluble.

Examples of the water-soluble adhesive include polyvinyl alcohol (PVA), polyvinylpyrrolidone, polyamide, polyacrylamide, polyethyleneimine, polyethylene oxide, polyacrylic acid resin, cellulose resin, gelatin and the like. Among these, polyvinyl alcohol is more preferably used in order to increase the strength and dimensional accuracy of the three-dimensional model.

The resin powder for three-dimensional modeling of the present invention has high fluidity, and as a result, the surface property of the obtained three-dimensional model can be improved, and these effects are not limited to the method using electromagnetic irradiation. It is effective in all three-dimensional modeling devices that employ the powder laminating method, including the binder jet method.

(Three-dimensional model)
The three-dimensional model can be suitably manufactured by the method for producing a three-dimensional model of the present invention.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

For the obtained resin powder for three-dimensional modeling, the "median value of the average circle equivalent diameter, the average circularity, and the median particle size distribution of the circle equivalent diameter" and the "loose filling rate" were measured as follows. The results are shown in Table 1 below.

[Median size distribution of average circle-equivalent diameter, average circularity, and circle-equivalent diameter]
For the average circle equivalent diameter and average circularity, a wet flow type particle diameter / shape analyzer (device name: FPIA-3000, manufactured by Sysmex Co., Ltd.) is used, and the number of powder particle counts is 3,000 or more. In the state of counting, a particle shape image was acquired, the equivalent circle diameter and circularity of particles having a particle diameter of 0.5 μm or more and 200 μm or less were measured, and the average value was obtained. The circularity was measured twice, and the average value was taken as the average circularity. In addition, the median value was calculated from the particle size distribution of the equivalent circle diameter.

[Loose filling rate]
The looseness filling rate was measured by using a bulk hydrometer (compatible with JIS Z-2504, manufactured by Kuramochi Kagaku Kikai Seisakusho Co., Ltd.). The "loose filling rate" of the powder was calculated by dividing the obtained loosening density by the true density of the resin.

(Example 1)
Polybutylene terephthalate (PBT) resin (trade name: Novaduran 5020, manufactured by Mitsubishi Engineering Plastics Co., Ltd., melting point: 218 ° C, glass transition temperature: 43 ° C) is melted using an extrusion processing machine (manufactured by Nippon Steel Works Co., Ltd.). After stirring at a higher temperature of 30 ° C., a resin solution for three-dimensional modeling was spread in a fibrous form using a circular nozzle hole. The number of threads coming out of the nozzle was 60. Stretch about 5 times to make a fiber with a fiber diameter of 55 μm and an accuracy of ± 4 μm, and then use a push-cut type cutting device (manufactured by Ogino Seiki Seisakusho Co., Ltd., NJ series 1200 type) to aim for a length of 55 μm. The particles were cut to obtain substantially cylindrical particles, which were used as resin powder for three-dimensional modeling. When the cross section after cutting was confirmed using a scanning electron microscope (device name: S4200, manufactured by Hitachi, Ltd.) at a magnification of 300 times, the cross section was cut cleanly and the cut surfaces were parallel to each other. .. Moreover, when the height of the substantially cylindrical body was measured, it was possible to cut with an accuracy of 55 μm ± 10 μm. The obtained resin powder for three-dimensional modeling was passed through a sieve having an opening of 125 μm to eliminate coarse particles such as partial cutting defects. FIG. 4 shows the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Example 1.

(Example 2)
In Example 1, the polybutylene terephthalate (PBT) resin was changed to a polyamide 66 (PA66) resin (trade name: Leona 1300S, manufactured by Asahi Kasei Chemicals Co., Ltd., melting point: 265 ° C.), and the target fiber diameter was 140 μm. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that the fiber length was 140 μm.

(Example 3)
In Example 1, the polybutylene terephthalate (PBT) resin was changed to a polyamide 9T (PA9T) resin (trade name: Genesta N1000A, manufactured by Kuraray Co., Ltd., melting point: 306 ° C.), and further, the target fiber diameter was 15 μm and the target fiber. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that the length was 15 μm.

(Example 4)
In Example 1, the polybutylene terephthalate (PBT) resin was changed to a polypropylene (PP) resin (trade name: Novatec MA3, manufactured by Nippon Polypro Co., Ltd., melting point: 130 ° C., glass transition temperature: 0 ° C.), and further aimed. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that the fiber diameter was 55 μm and the target fiber length was 55 μm.

(Example 5)
In Example 1, the polybutylene terephthalate (PBT) resin was changed to a polyetheretherketone (PEEK) resin (trade name: HT P22PF, manufactured by VICTREX, melting point: 334 ° C., glass transition temperature: 143 ° C.), and further. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that the target fiber diameter was 55 μm and the target fiber length was 55 μm.

(Example 6)
In Example 1, the polybutylene terephthalate (PBT) resin was changed to a polyacetal (POM) resin (trade name: Iupital F10-01, manufactured by Mitsubishi Engineering Plastics Co., Ltd., melting point: 175 ° C.), and the target fiber diameter was 55 μm. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that the target fiber length was 55 μm.

(Example 7)
The resin powder for three-dimensional modeling obtained in Example 1 was placed in a stainless steel container and stirred. The stirring work was performed on a stainless steel container with SKH-100 manufactured by Misugi Co., Ltd. for 30 minutes.
The weight of the resin powder for three-dimensional modeling and the area of the inner wall of the container set in the stainless steel container were 1 [kg / m ² ]. After performing these treatments, the powder was transferred to another container by gravity, and the powder adhering to the wall surface was separated and treated as waste. By these treatments, a resin powder for three-dimensional modeling was obtained.

(Example 8)
The resin powder for three-dimensional modeling obtained in Example 4 was stirred in a stainless steel container in the same manner as in Example 7 to obtain a resin powder for three-dimensional modeling.

(Example 9)
The resin powder for three-dimensional modeling obtained in Example 1 was passed through the air transfer system. The piping was made of stainless steel.
The weight of the resin powder for three-dimensional modeling and the area of the inner wall of the container that passed through the air transfer system made of piping stainless steel were set to 1 [kg / m ² ]. The powder adhering to the wall surface was separated by these treatments and treated as waste. By these treatments, a resin powder for three-dimensional modeling was obtained.

(Example 10)
The resin powder for three-dimensional modeling obtained in Example 4 was stirred in a stainless steel container in the same manner as in Example 9 to obtain a resin powder for three-dimensional modeling.

(Comparative Example 1)
In Example 1, the resin powder for three-dimensional modeling is the same as in Example 1 except that the particles are not processed and formed and a powder material made of PA12 (trade name: aspex-PA, manufactured by Aspect Co., Ltd.) is used. Got FIG. 5 shows the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Comparative Example 1.

(Comparative Example 2)
In Example 1, the resin powder for three-dimensional modeling is the same as in Example 1 except that the powder material (trade name: aspex-FPA, manufactured by Aspect Co., Ltd.) made of PA11 is used without processing and forming the particles. Got FIG. 6 shows the distribution of the equivalent circle diameter of the resin powder for three-dimensional modeling of Comparative Example 2.

(Comparative Example 3)
In Example 1, the resin for three-dimensional modeling is the same as in Example 1 except that the powder material made of PPS (trade name: ASPEX-PPS, manufactured by Aspect Co., Ltd.) is used without processing and forming the particles. Obtained powder.

(Comparative Example 4)
In Example 1, the polybutylene terephthalate (PBT) resin is freeze-milled at −200 ° C. using a low-temperature pulverization system (device name: Linlex Mill LX1, manufactured by Hosokawa Micron Co., Ltd.) to obtain a resin powder for three-dimensional modeling. A resin powder for three-dimensional modeling was obtained in the same manner as in Example 1 except that it was obtained.

The obtained resin powder for three-dimensional modeling was evaluated for "dimensional accuracy", "surface property (orange peel property)", "tensile strength", and "modeling object density" as follows. The results are shown in Table 1 below.

<Dimensional accuracy>
The obtained resin powder for three-dimensional modeling was stored in an RH environment at 27 ° C. and a humidity of 80% for 1 week. Using the resin powder for three-dimensional modeling after storage for one week, a three-dimensional modeling device was manufactured using an SLS-type three-dimensional modeling device (AM S5500P, manufactured by Ricoh Co., Ltd.). The setting conditions were set to an average thickness of the powder layer of 0.1 mm, a laser output of 10 watts or more and 150 watts or less, a laser scanning space of 0.1 mm, and a floor temperature of -3 ° C. from the melting point of the resin.
The sample for dimensional accuracy evaluation was a rectangular parallelepiped having a side of 50 mm and an average thickness of 5 mm, and a three-dimensional model was prepared based on CAD data, and this was used as a sample for dimensional accuracy evaluation. The difference between the CAD data of the sample for dimensional accuracy evaluation and the length of each side of the actually modeled sample was obtained, the average value was used as the dimensional difference, and the "dimensional accuracy" was evaluated based on the following evaluation criteria.
[Evaluation criteria]
⊚: Dimensional difference is 0.02 mm or less ○: Dimensional difference is more than 0.02 mm and 0.05 mm or less Δ: Dimensional difference is more than 0.05 mm and 0.10 mm or less ×: Dimensional difference is more than 0.10 mm and 0.15 mm or less

<Surface (orange peel)>
Using the three-dimensional modeling sample used for the evaluation of the "dimensional accuracy", the surface was visually observed, observed with an optical microscope, and a sensory test was performed. In the sensory test, the sample was touched by hand, and the surface texture, especially smoothness, was evaluated from the tactile sensation. These results were integrated and the surface property (orange peel property) was evaluated based on the following evaluation criteria.
(Evaluation criteria)
⊚: The surface is very smooth, and there are almost no worrisome irregularities or rough surfaces. ○: There is no problem with the smoothness of the surface, and the unevenness or rough surface of the surface is acceptable. Unevenness and rough surface can be visually recognized ×: The surface is caught, and many defects such as unevenness and distortion of the surface are recognized.

<Tensile strength>
Similar to the evaluation of "dimensional accuracy", using the resin powder for three-dimensional modeling after storage for one week, set the same equipment and the same conditions as when preparing the sample for dimensional accuracy evaluation, and focus on the tensile test specimen sample. Five pieces were formed in the longitudinal direction of the tensile test specimen so that the long side faces the part in the Y-axis direction. The distance between each model layer was 5 mm. As the tensile test specimen sample, an ISO (International Organization for Standardization) 3167 Type1A 150 mm long multipurpose dog bone-like test specimen (the specimen has a central portion of 80 mm in length, 4 mm in thickness, and 10 mm in width) was used.
A tensile test was carried out on the obtained tensile test sample (three-dimensional model) using a tensile test (manufactured by Shimadzu Corporation, AGS-5kN) according to ISO 527. The test speed in the tensile test was 50 mm / min. From the average value of the tensile strength of the obtained 5 tensile test sample samples, the tensile strength was evaluated based on the following evaluation criteria.
[Evaluation criteria]
⊚: Tensile strength is 100 MPa or more ○: Tensile strength is 50 MPa or more and less than 100 MPa Δ: Tensile strength is 30 MPa or more and less than 50 MPa ×: Tensile strength is less than 30 MPa

<Density of modeled object>
Using the three-dimensional modeling sample used for the evaluation of the "dimensional accuracy", the measurement was performed by the Archimedes method (device name: AD-1653 / AD-1654, manufactured by A & D Co., Ltd.). Ion-exchanged water was used as the sample solvent. The measurement was performed so that bubbles did not form around the sample.

From the results in Table 1, in Examples 1 to 10, the particles are attracted to the metal surface because the mirror image force acts between the particles and the metal surface. The amount of charge of the small particle size particles is relatively large because the volume specific surface area is large. It easily adheres to the metal surface due to the mirror image force. Therefore, the small particle size particles selectively increase the powder adhesion to the metal surface. Stirring increases the chances of smaller particle size particles adhering to the wall surface.
On the other hand, since the powder that does not adhere to the wall surface has relatively large particles, it is possible to classify the powder by utilizing the mirror image force.

Examples of aspects of the present invention are as follows.
<1> The average circle equivalent diameter based on the number is 10 μm or more and 150 μm or less.
The resin powder for three-dimensional modeling is characterized in that the median value of the particle size distribution having a diameter equivalent to a circle is larger than the average value of the particle size distribution having a diameter equivalent to a circle.
<2> The resin powder for three-dimensional modeling according to <1>, which contains prism-shaped particles.
<3> The resin powder for three-dimensional modeling according to <2>, wherein the columnar particles have a cylinder length of 10 μm or more and 150 μm or less and a cylinder diameter of 10 μm or more and 150 μm or less.
<4> The resin powder for three-dimensional modeling according to any one of <1> to <3>, wherein the average circularity is 0.75 or more and 0.90 or less.
<5> The resin powder for three-dimensional modeling according to any one of <1> to <4>, which contains a crystalline resin and is at least one selected from polyolefin, polyamide, polyester, polyarylketone, and polyphenylene sulfide. Is.
<6> The resin powder for three-dimensional modeling according to <5>, wherein the polyester is at least one selected from polyethylene terephthalate, polybutadiene terephthalate, and polylactic acid.
<7> The resin powder for three-dimensional modeling according to any one of <5> to <6>, wherein the polyolefin is polyethylene or polypropylene.
<8> The resin powder for three-dimensional modeling according to any one of <1> to <7>, which further contains an antioxidant.
<9> The resin powder for three-dimensional modeling according to <8>, wherein the content of the antioxidant is 0.05% by mass or more and 5% by mass or less.
<10> The resin powder for three-dimensional modeling according to <9>, wherein the content of the antioxidant is 0.1% by mass or more and 3% by mass or less.
<11> The resin powder for three-dimensional modeling according to <10>, wherein the content of the antioxidant is 0.2% by mass or more and 2% by mass or less.
<12> The resin powder for three-dimensional modeling according to any one of <1> to <11>, which further contains a plasticizer.
<13> The resin powder for three-dimensional modeling according to any one of <1> to <12>, which further contains a stabilizer.
<14> The resin powder for three-dimensional modeling according to any one of <1> to <13>, which further contains a crystal nucleating agent.
<15> The resin powder for three-dimensional modeling according to any one of <1> to <14>, which further contains a strengthening agent.
<16> The resin powder for three-dimensional modeling according to <15>, wherein the reinforcing agent is at least one selected from glass fillers, glass beads, carbon fibers, and aluminum balls.
<17> The resin powder for three-dimensional modeling according to <16>, wherein the reinforcing agent is at least one of a glass filler and carbon fiber.
<18> The reinforcing agent is carbon fiber, which is the resin powder for three-dimensional modeling according to <17>.
<19> The layer forming step of forming a layer containing the resin powder for three-dimensional modeling according to any one of <1> to <18>.
It is a method for producing a three-dimensional model, which comprises repeating a powder bonding step of adhering the resin powders for three-dimensional modeling in a selected region of the layer to each other.
<20> A layer forming means for forming a layer containing the resin powder for three-dimensional modeling according to any one of <1> to <18>.
It is an apparatus for producing a three-dimensional model, characterized by having a powder bonding means for adhering the resin powders for three-dimensional modeling in a selected region of the layer.
<21> The three-dimensional object manufacturing apparatus according to <20>, wherein the powder bonding means is a means for irradiating electromagnetic waves.
<22> The three-dimensional model is characterized in that it is modeled by the method for manufacturing the three-dimensional model according to the above <19>.

The resin powder for three-dimensional modeling according to any one of <1> to <18>, the method for producing a three-dimensional model according to <19>, and the three-dimensional modeling according to any one of <20> to <21>. The product manufacturing apparatus and the three-dimensional model according to <22> can solve the conventional problems and achieve the object of the present invention.

Japanese Unexamined Patent Publication No. 2015-180538 Japanese Patent Publication No. 2014-522331 Special Table 2013-528599 Japanese Patent Publication No. 2015-515434

Claims (9)

The average circle equivalent diameter based on the number is 10 μm or more and 150 μm or less.
The median particle size distribution of the equivalent circle diameter is larger than the average equivalent circle diameter.
A resin powder for three-dimensional modeling characterized by a loose filling rate of 40.4% or more. The resin powder for three-dimensional modeling according to claim 1, which contains prism-shaped particles. The resin powder for three-dimensional modeling according to claim 2, which is composed of prism-shaped particles whose bottom surface and top surface are substantially parallel to each other. The resin powder for three-dimensional modeling according to any one of claims 2 to 3, wherein the columnar particles have a cylinder length of 10 μm or more and 150 μm or less and a cylinder diameter of 10 μm or more and 150 μm or less. The resin powder for three-dimensional modeling according to any one of claims 1 to 4, wherein the loose filling rate is 40.4% or more and 50% or less. The resin powder for three-dimensional modeling according to any one of claims 1 to 5, wherein the average circularity is 0.75 or more and 0.90 or less. The resin powder for three-dimensional modeling according to any one of claims 1 to 6, which comprises a crystalline resin, wherein the crystalline resin is at least one selected from polyolefin, polyamide, polyester, polyarylketone, and polyphenylene sulfide. The resin powder for three-dimensional modeling according to any one of claims 1 to 7, wherein the resin powder for three-dimensional modeling contains at least one selected from polyethylene terephthalate, polybutadiene terephthalate, and polylactic acid. A layer forming step for forming a layer containing the resin powder for three-dimensional modeling according to any one of claims 1 to 8.
A method for producing a three-dimensional model, which comprises repeating a powder bonding step of adhering the resin powders for three-dimensional modeling in a selected region of the layer to each other.

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