JP7183641B2 - Particles for three-dimensional modeling, powder for three-dimensional modeling, apparatus for producing three-dimensional article, method for producing three-dimensional article, method for producing powder for three-dimensional modeling, and particles - Google Patents

Description

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

A powder bed fusion (PBF) method is known as a method for manufacturing a three-dimensional object. Known PBF methods include the SLS (selective laser sintering) method in which a laser is selectively irradiated to form a three-dimensional object, and the SMS (selective mask sintering) method in which a mask is used to irradiate a laser on a plane. . In addition to the PBF method, the HSS (high speed sintering) method using ink, the BJ (Binder jetting) method, and the like are known as methods for manufacturing three-dimensional objects.

As the resin powder used in manufacturing the three-dimensional object, for example, resin fibers are formed by extruding a resin melt and then stretching the resin fibers, which are fixed with a movable clamp and moved toward the cutting blade. , a substantially cylindrical resin powder obtained by cutting resin fibers is disclosed (Patent Document 1).

However, the resin powder of Patent Document 1 is inferior in packing density, and a three-dimensional object formed using the resin powder is inferior in strength.

The invention according to claim 1 is a columnar shape having an end face and a side face, wherein the end face includes a first face and a second face, and at least the first face is a first opposing face. and an outer peripheral region having a shape in which the first opposing surface extends along the side surface and is a surface continuous with the first opposing surface, wherein the outer peripheral region covers a part of the side surface. It is a particle for three -dimensional modeling.

The particles for three-dimensional modeling of the present invention are excellent in packing density, and a three-dimensional article formed using the resin powder has an effect of being excellent in strength.

FIG. 1 is a photograph showing an example of powder for stereolithography. FIG. 2 is a photograph showing an example of particles for stereolithography. FIG. 3A is a schematic perspective view showing an example of cylindrical particles for stereolithography. FIG. 3B is a side view showing an example of the cylindrical three-dimensional modeling particles in FIG. 3A. FIG. 3C is a side view showing an example of particles for three-dimensional modeling that do not have a vertex at the end of a cylindrical shape. FIG. 3D is a side view showing an example of particles for three-dimensional modeling that do not have apexes at the ends of the cylindrical shape. FIG. 3E is a side view showing an example of particles for three-dimensional modeling that do not have vertices at the end of a cylindrical shape. FIG. 3F is a side view showing an example of particles for three-dimensional shaping that do not have apexes at the ends of the cylindrical shape. FIG. 3G is a side view showing an example of particles for three-dimensional modeling that do not have apexes at the end of a cylindrical shape. FIG. 3H is a side view showing an example of particles for three-dimensional modeling that do not have apexes at the end of a cylindrical shape. FIG. 3I is a side view showing an example of particles for three-dimensional modeling that do not have apexes at the end of a cylindrical shape. FIG. 4 is a schematic diagram showing an example of a cut product formed by obliquely cutting a columnar resin. FIG. 5 is a schematic diagram showing a three-dimensional object manufacturing apparatus according to one embodiment of the present invention. FIG. 6 is a conceptual diagram for explaining the method of manufacturing a three-dimensional object. FIG. 7 is a conceptual diagram for explaining a method of manufacturing a three-dimensional object.

Embodiments of the present invention will be described below. In addition, the three-dimensional modeling particles described below are an example of the particles, and the present application is not limited thereto. Therefore, particles other than particles for three-dimensional modeling, for example, surface contracting agents, spacers, lubricants, paints, grindstones, additives, secondary battery separators, foods, cosmetics, clothes, automobiles, precision equipment, semiconductors, aerospace, It may be particles used in medical applications, metal substitute materials, and the like.

<<Powder for stereolithography>>
The three-dimensional modeling powder of the present embodiment means an aggregate of a plurality of granules, and is a three-dimensional modeling particle having a columnar shape having end faces and side faces, with one of the end faces partially covering the side face. including. In addition, the three-dimensional modeling powder may contain particles that do not correspond to the three-dimensional modeling particles, in addition to the three-dimensional modeling particles described below.

<Particles for stereolithography>
-Shape of particles for stereolithography-
First, particles for three-dimensional modeling (hereinafter also referred to as "pillars") will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 is a photograph showing an example of powder for stereolithography. Also, the pillar surrounded by the dotted circle in FIG. 1 indicates one of the plurality of pillars in FIG. FIG. 2 is a photograph showing an example of particles for stereolithography. 1 and 2 are photographs obtained by SEM (scanning electron microscope) observation. Means for obtaining such a photograph (projection image) is not limited to SEM, and a known image analysis apparatus such as an optical microscope can be used. A case where a scanning electron microscope) is used will be described.

As shown in FIG. 2 , the columnar body 21 has a first surface 22 that is an example of an end surface, a second surface 23 that is an example of an end surface, and side surfaces 24 . The first surface 22 has a first opposing surface 22 a and a first surface outer peripheral region 22 b having a shape extending along the side surface 24 . The outer peripheral region 22b of the first surface is a surface that is continuous with the first opposing surface 22a via a curved surface and is substantially orthogonal to the first opposing surface 22a. The second surface 23 has a second opposing surface 23 a facing the first opposing surface 22 a and an outer peripheral region 23 b of the second surface extending along the side surface 24 . The outer peripheral region 23b of the second surface is a surface continuous with the second facing surface 23a via a curved surface, and is substantially perpendicular to the second facing surface 23a. Side 24 adjoins first surface 22 and second surface 23 . On the side surface 24, a first surface outer peripheral region 22b and a second surface outer peripheral region 23b extend. In other words, the side surface 24 is covered by bending the end surface of the columnar body 21 . As in the present embodiment, both the end faces preferably cover the entire circumference of the side surface in the range observed with a SEM (scanning electron microscope), but both the end faces cover part of the side surface. In this case, one of the end faces may cover the entire circumference of the side surface, or one of the end faces may cover a part of the side surface. In addition, it is not limited to the range observed by SEM (scanning electron microscope), and it is preferable that both the end faces cover the entire circumference of the side surface, but when both the end faces cover a part of the side surface , one of the end faces may cover the entire circumference of the side surface, or one of the end faces may cover a portion of the side surface.

In addition, the shape of the outer peripheral region 22b of the first surface and the outer peripheral region 23b of the second surface (hereinafter also referred to as “peripheral region”) may be a shape that can be distinguished from the side surface 24 in an SEM image or the like. It includes a shape in which a part of the area is integrated with the side surface 24, a shape in which the outer peripheral area is in contact with the side surface 24, a shape in which a space exists between the outer peripheral area and the side surface 24, and the like. In addition, it is preferable that the outer peripheral region 22b of the first surface and the outer peripheral region 23b of the second surface are provided so as to have substantially the same surface direction as the surface direction of the side surface 24 .

In addition, as shown in FIG. 2 , the outer peripheral region 22 b of the first surface and the outer peripheral region 23 b of the second surface extend along the side surface 24 and are positioned on the side surface 24 . In addition, the characteristic structure of the first surface and the second surface that covers the vicinity of the connection area between the outer peripheral region 22b of the first surface and the outer peripheral region 23b of the second surface and the side surface 24 is the shape of a bottle cap. Also called

The outer peripheral region of the first surface and the outer peripheral region of the second surface are shaped such that the first surface and the second surface extend along the side surfaces, respectively. Therefore, the outer peripheral region of the first surface and the first opposing surface and the outer peripheral region of the second surface and the second opposing surface are smoothly continuous via curved surfaces. A powder for three-dimensional modeling including a columnar body by providing an outer peripheral region of the first surface and an outer peripheral region of the second surface, and making the columnar body have no corners or reduce the ratio of the corners It is possible to increase the packing density of and improve the tensile strength of the modeled product. In addition, since the pillars do not have corners, the fluidity of the 3D modeling powder including the pillars can be improved, and poor movement of the 3D modeling powder during 3D modeling can be suppressed. Therefore, the tensile strength of the model can be improved. In addition, when the entire outer peripheral region of the first surface and the entire outer peripheral region of the second surface are columns having a shape extending along the side surface (shape covering the side surface), it is used for three-dimensional modeling. The packing density of the pillars required above and the fluidity of the pillars can be further improved.

In the peripheral region of the first surface and the peripheral region of the second surface, which are regions where the end faces of the column cover the side surfaces, the length of the shortest part in the height direction of the column is 1 μm or more. It is preferably 3 μm or more, more preferably 5 μm or more, further preferably 5 μm or more. When it is 1 μm or more, the curved surface between the outer peripheral region of the first surface and the first opposing surface and between the outer peripheral region of the second surface and the second opposing surface becomes smoother, and the columnar body The filling density of the three-dimensional modeling powder containing can be increased, and the tensile strength of the model can be improved. In addition, by making the curved surface smoother, it is possible to improve the flowability of the three-dimensional modeling powder including the columnar body, and it is possible to suppress the movement failure of the three-dimensional modeling powder during three-dimensional modeling. Tensile strength can be improved. The outer peripheral region of the first surface and the outer peripheral region of the second surface are lengths in the height direction of the pillar, and the length of the longest portion is preferably 10 μm or more, and 15 μm or more. It is more preferable to have It should be noted that all of the above lengths are lengths within a range observed in a projection image of a SEM (scanning electron microscope) or the like.

The shape of the columnar body is not particularly limited, and can be appropriately selected according to the purpose. Examples thereof include a three-dimensional shape such as a substantially cylindrical column and a substantially prismatic shape, and a substantially prismatic shape is preferable. In addition, the shape of a substantially cylindrical column and a substantially prismatic shape includes a three-dimensional shape having the outer peripheral region of the first surface and the outer peripheral region of the second surface. The three-dimensional shape of the column determines the shape of the first opposing surface and the second opposing surface of the column. For example, when a line (corner) in the height direction of the pillar cannot be observed and a smooth surface can be observed uniformly, the pillar is substantially cylindrical, and the first opposing surface and the second opposing surface has a substantially circular shape. In addition, when a plurality of surfaces separated by lines (corners) in the height direction of the columnar body can be observed, the columnar body is substantially a prism, and the shape of the first facing surface and the second facing surface is substantially It becomes a polygonal shape. In addition, the first facing surface may be substantially polygonal and the second facing surface may be substantially circular, and the first facing surface may be substantially circular and the second facing surface may be It may have a substantially polygonal shape.

The pillar has a first facing surface and a second facing surface, which are facing surfaces as described above. The first opposing surface may have an inclination with respect to the second opposing surface, but it is preferable that the inclination is substantially parallel to the second opposing surface. By being substantially parallel, it is possible to improve the flowability of the powder for three-dimensional modeling including the columnar bodies.

In addition, the ratio of the length of the longest straight line that can be drawn on the first opposing surface or the second opposing surface of the column to the height of the column is preferably 0.5 times or more and 5.0 times or less, 0.7 times or more and 2.0 times or less is more preferable, and 0.8 times or more and 1.5 times or less is even more preferable.

-- Roughly cylindrical shape --
The shape of the substantially circular cylinder is not particularly limited and can be appropriately selected according to the purpose. A substantially elliptical cylindrical body, which is an ellipse, and the like are included. Among these, a substantially true cylindrical body is preferable. Note that a part of the circular portion of the substantially cylindrical body may be missing. Also, the substantially circular means that the ratio of the major axis to the minor axis (long axis/short axis) is 1 or more and 10 or less.

The sizes of the areas of the first opposing surface and the second opposing surface may be slightly different, but the ratio of the diameters of the circles of the large surface and the small surface (large surface/small surface) is 1.5. It is preferably 1.1 times or less because the density can be reduced if the shape is uniform.

The diameter of the substantially cylindrical body is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm or more and 100 μm or less. In addition, when the circular portion of the substantially cylindrical body is substantially elliptical, the diameter means the major axis.

The height of the substantially cylindrical body is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm or more and 100 μm or less.

-- Rough prismatic shape --
The shape of the substantially prismatic prism is not particularly limited and can be appropriately selected according to the purpose. , substantially triangular prism, substantially hexagonal prism, and the like. Among these, a substantially hexagonal prism is preferable, and a substantially regular hexagonal prism is more preferable. Since the shape is a substantially prismatic shape, it is possible to close the space without gaps, and the tensile strength of the obtained three-dimensional object can be improved. In addition, a part of the substantially prismatic column may be missing.

Although the sizes of the areas of the first opposing surface and the second opposing surface may be slightly different, the ratio of the average value of the polygon sides of the large surface and the small surface (large surface/small surface) is , is preferably 1.5 times or less, and more preferably 1.1 times or less because the density can be reduced when the shape is uniform.

The length of the longest straight line that can be drawn on the first opposing surface or the second opposing surface of the substantially prismatic prism is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm or more and 100 μm or less.

The height of the substantially prism is not particularly limited and can be appropriately selected depending on the purpose, but is preferably 5 μm or more and 100 μm or less.

The side forming the height between the first opposing surface and the second opposing surface of the column is in the scope of the present embodiment even if the resin is softened during cutting and the state is collapsed (for example, a barrel shape in a cylindrical shape). However, it is preferable that the sides are straight because the space is left between the arcs and the powder can be densely packed.

--shapes without vertices--
Preferably, the pillars do not have vertices. A vertex refers to a corner portion that exists when the column is viewed from the side. The shape of the pillar will be described with reference to FIGS. 3A to 3I. FIG. 3A is a schematic perspective view showing an example of cylindrical particles for stereolithography. FIG. 3B is a side view showing an example of the cylindrical three-dimensional modeling particles in FIG. 3A. FIG. 3C is a side view showing an example of particles for three-dimensional modeling that do not have a vertex at the end of a cylindrical shape. 3D to 3I are side views showing other examples of three-dimensional shaping particles that do not have apexes at the ends of their cylindrical bodies.

When the cylindrical body shown in FIG. 3A is observed from the side, it has a rectangular shape as shown in FIG. 3B, and has four corner portions, that is, vertices. An example of a shape without vertices at this end is shown in FIGS. 3C-3I. The presence or absence of the apex of the column can be determined from the projection image on the side surface of the column. For example, the side surfaces of the columnar particles are observed using a scanning electron microscope (device name: S4200, manufactured by Hitachi, Ltd.) or the like to obtain a two-dimensional image. In this case, the projected image becomes a quadrilateral, and if the part formed by two adjacent sides is the edge, and if it is formed by only two adjacent straight lines, an angle will be formed and it will have a vertex. , 3C to 3I, when the ends are formed by arcs, the ends do not have vertices.

- Content of three-dimensional modeling particles (cylinders) -
The content (number basis) of the pillars contained in the three-dimensional modeling powder is preferably 50% or more, more preferably 70% or more, relative to the three-dimensional modeling powder.

In the three-dimensional modeling powder, by increasing the content of the pillars having the outer peripheral region of the first surface and the outer peripheral region of the second surface as described above, the packing density of the three-dimensional modeling powder containing the pillars can be increased, and the tensile strength of the shaped article can be improved. In addition, by increasing the content of the pillars having the outer peripheral region of the first surface and the outer peripheral region of the second surface, it is possible to improve the fluidity of the powder for three-dimensional modeling, which includes the three-dimensional modeling. Since it is possible to suppress movement failure of the three-dimensional modeling powder at times, it is possible to improve the tensile strength of the modeled object.

A specific method for calculating the content of the columnar bodies is performed by the following procedure. That is, a photograph was taken with a SEM (scanning electron microscope) at a magnification of 150 times, and the number of the three-dimensional modeling powder and the number of pillars were obtained from the photographed image. It is calculated by dividing by the number of and multiplying by 100.

Note that the magnification of the SEM (scanning electron microscope) can be appropriately changed depending on the size of the three-dimensional modeling powder. In addition, when obtaining the number of three-dimensional modeling powder and the number of pillars from the SEM image, in the present application, only the three-dimensional modeling powder and the three-dimensional modeling powder with the longest part of 20 μm or more in the SEM image are counted. . Also, it is assumed that the number of pieces of the powder for three-dimensional modeling is 100 or more when calculating the content of the pillars.

It is preferable that the content (based on number) of substantially prismatic columns contained in the three-dimensional modeling powder is 40% or more of the three-dimensional modeling powder.

In the three-dimensional modeling powder, by increasing the content of the substantially prismatic pillars having the outer peripheral region of the first surface and the outer peripheral region of the second surface as described above, the pillars are formed as described above. It is possible to improve the packing density of the powder for three-dimensional modeling and the tensile strength of the resulting three-dimensional article.

-Crystallinity of Particles for Solid Modeling (Cylinders)-
A thermoplastic resin can be used for the pillar. A thermoplastic resin means a material that is plasticized and melted when heat is applied. Among thermoplastic resins, crystalline resins may be used. The crystalline resin means a resin having a melting peak when measured according to ISO 3146 (method for measuring plastic transition temperature, JIS K7121).

As the crystalline resin, a crystalline thermoplastic resin whose crystals are controlled is preferable, and the crystal size and crystal orientation are controlled by external stimulus methods such as heat treatment, stretching, crystal nucleating material, and ultrasonic treatment. Plastic resins are more preferred.

The method for producing the crystalline thermoplastic resin is not particularly limited and can be appropriately selected according to the purpose. There is a method of adding a crystal nucleating agent to increase the crystallinity and then performing an annealing treatment. In addition, the crystallinity can be enhanced by applying ultrasonic waves, the crystallinity can be enhanced by dissolving in a solvent and slowly volatilizing, or by undergoing a process such as crystal growth by applying an external electric field, or stretching. A method of pulverizing, cutting, or otherwise processing the highly oriented and highly crystalline material by means of such a method is exemplified.

Annealing can be performed by heating the resin at a temperature 50° C. higher than the glass transition temperature for 3 days and then slowly cooling it to room temperature.

For stretching, an extruder is used to stretch the resin solution for three-dimensional modeling into fibrous form while stirring at a temperature 30° C. or more higher than the melting point. At this time, the melt is drawn to a fiber by about 1 to 10 times. For stretching, the maximum stretching ratio can be changed for each resin and each melt viscosity.

As ultrasonic waves, glycerin (manufactured by Tokyo Kasei Kogyo Co., Ltd., reagent grade) solvent is added about 5 times to the resin, then heated to a temperature 20 ° C. higher than the melting point, and an ultrasonic generator (manufactured by Hielscher, It can be performed by applying ultrasonic waves at 24 kHz and an amplitude of 60% for 2 hours using an ultrasonicator UP200S. Then, it is preferable to vacuum-dry after washing|cleaning with the solvent of isopropanol at room temperature.

The external electric field application treatment can be carried out by heating the resin to a temperature higher than the glass transition temperature, applying an AC electric field (500 Hz) of 600 V/cm for 1 hour, and then slowly cooling the resin.

In the PBF method, it is preferable that the temperature width (temperature window) for crystal layer change is large because warping can be suppressed when creating a three-dimensional object. A resin powder having a large difference between the melting start temperature and the recrystallization point at the time of cooling has better moldability, so it is preferable that there is a greater difference in the crystal layer change.

-Composition of three-dimensional modeling particles (cylinders)-
Examples of the resin constituting the columnar body include polymers such as polyolefin, polyamide, polyester, polyether, polyphenylene sulfide, liquid crystal polymer (LCP), polyacetal (POM, melting point: 175° C.), polyimide, and fluorine resin. . These may be used individually by 1 type, and may use 2 or more types together. The thermoplastic resin may contain additives such as flame retardants, plasticizers, thermal stability additives and crystal nucleating agents, and polymer particles such as non-crystalline resins, in addition to the above polymers. These may be used individually by 1 type, and may use 2 or more types together.

Examples of polyolefin include polyethylene and polypropylene (PP, melting point: 180°C). These may be used individually by 1 type, and may use 2 or more types together.

Examples of polyamides include polyamide 410 (PA410), polyamide 6 (PA6), polyamide 66 (PA66, melting point: 265°C), polyamide 610 (PA610), polyamide 612 (PA612), polyamide 11 (PA11), polyamide 12 ( PA12); semi-aromatic polyamide 4T (PA4T), polyamide MXD6 (PAMXD6), polyamide 6T (PA6T), polyamide 9T (PA9T, melting point: 300°C), polyamide 10T (PA10T), and the like. These may be used individually by 1 type, and may use 2 or more types together. Among these, PA9T, also called polynonamethylene terephthalamide, is composed of a 9-carbon diamine and a terephthalic acid monomer, and is generally called semi-aromatic because the carboxylic acid side is aromatic. Furthermore, the polyamide of the present embodiment also includes a polyamide called aramid which is composed of p-phenylenediamine and a terephthalic acid monomer as a wholly aromatic group in which the diamine side is also aromatic.

Examples of polyesters include polyethylene terephthalate (PET, melting point: 260°C), polybutadiene terephthalate (PBT, melting point: 218°C), and polylactic acid (PLA). In order to impart heat resistance, a polyester containing aromatics partially containing terephthalic acid or isophthalic acid can also be suitably used in this embodiment.

Polyethers include, for example, polyetheretherketone (PEEK, melting point: 343° C.), polyetherketone (PEK), polyetherketoneketone (PEKK), polyaryletherketone (PAEK), polyetheretherketoneketone (PEEKK ), polyether ketone ether ketone ketone (PEKEKK), and the like. Besides polyether, any crystalline polymer may be used, and examples thereof include polyacetal, polyimide, and polyethersulfone. A material having two melting peaks such as PA9T may be used (in order to melt completely, the resin temperature must be raised above the second melting point peak).

The pillars may contain optional fluidizing agents, granulating agents, reinforcing agents, antioxidants, and the like. The content of the fluidizing agent may be an amount sufficient to cover the particle surface, and is preferably 0.1% by mass or more and 10% by mass or less based on the columnar body. As the fluidizing agent, a particulate inorganic material having a volume average particle diameter of less than 10 μm can be suitably used.

<<physical properties of powder>>
The powder for stereolithography as an example of the powder containing columnar bodies preferably satisfies at least one selected from the following (1) to (3).

(1) In differential scanning calorimetry, Tmf1 is 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 in accordance with ISO 3146, and then 10°C/min. When the temperature is lowered to −30° C. or lower at 10° C./min and is further raised to a temperature 30° C. higher than the melting point at 10° C./min, Tmf2 is the melting start temperature of the endothermic peak, Tmf1>Tmf2. Become. The melting start temperature of the endothermic peak is obtained by drawing a straight line parallel to the x-axis from the point where the amount of heat becomes constant after the end of heat absorption at the melting point, to the low temperature side, and descending from the straight line by -15 mW. temperature.

(2) In differential scanning calorimetry, Cd1 is 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, After that, the temperature is lowered at 10°C/min to -30°C or lower, and the temperature is further raised at 10°C/min to a temperature higher than the melting point by 30°C. When Cd2, Cd1>Cd2.

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

The above (1) to (3) define properties of the same three-dimensional modeling powder from different viewpoints, and the above (1) to (3) are related to each other.

[Method for measuring dissolution initiation temperature by differential scanning calorimetry under condition (1)]
As a method for measuring the dissolution initiation temperature by differential scanning calorimetry (DSC) of condition (1), a differential scanning calorimeter (for example, stock DSC-60A manufactured by Shimadzu Corporation) is used to measure the melting start temperature (Tmf1) of the endothermic peak when the temperature is raised to a temperature 30° C. higher than the melting point at 10° C./min. Thereafter, 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 when the temperature is raised to a temperature higher than the melting point by 30°C at 10°C/min. . The melting start temperature of the endothermic peak is obtained by drawing a straight line parallel to the x-axis from the point where the amount of heat becomes constant after the end of heat absorption at the melting point, to the low temperature side, and descending from the straight line by -15 mW. temperature.

[Method for measuring crystallinity by differential scanning calorimetry under condition (2)]
As a method for measuring the degree of crystallinity by differential scanning calorimetry (DSC) of condition (2), 30 ° C. higher than the melting point at 10 ° C./min in accordance with ISO 3146 (plastic transition temperature measurement method, JIS K7121) The amount of energy (heat of fusion) at the endothermic peak when the temperature is raised to the temperature is measured, and the degree of crystallinity (Cd1) can be obtained from the heat of fusion with respect to the heat of complete crystallization. After that, the temperature was lowered to −30° C. or lower at 10° C./min, and then the temperature was raised to 30° C. higher than the melting point at 10° C./min. The degree of crystallinity (Cd2) can be obtained from the heat of fusion for .

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

<<Method for producing powder>>
A powder for three-dimensional modeling as an example of a powder is obtained by a fibrillation step of producing a columnar fibrous material from pellets or the like containing a material that constitutes particles for three-dimensional modeling, and integrating a plurality of produced fibrous materials. It is preferable to manufacture through an integration step of producing an integrated material, a cutting step of cutting the integrated material to obtain a cut product, and a stirring step of stirring the cut product.

In the fiberizing step, it is preferable to extend the resin solution in a fibrous state while stirring at a temperature higher than the melting point by 30°C or more using an extruder. It is preferable to draw the resin solution by a factor of 1 or more and 10 or less to form a fiber. At this time, the shape of the fiber cross section can be determined by the shape of the nozzle port of the extruder. For example, when the cross section is circular, the nozzle opening is also preferably circular. It should be noted that the crystallinity of the resin can be controlled by this step, as described above.

In the integration step, a plurality of fibrous materials produced in the fibrillation step are aligned in the same direction and integrated. Examples of the method of integration include a method of integrating into a sheet by applying pressure while heating, and a method of applying water to the fibers to cool them and fixing the fibers in ice to integrate them. It is preferable to use a method of applying pressure while heating to integrate into a sheet. This step allows the fibrous material to be immobilized. When the sheet is integrated by applying pressure while heating, the heat to be applied varies depending on the type of resin used, but is preferably below the melting point, and preferably above the melting point by 100°. . Moreover, the applied pressure is preferably 10 MPa or less. The above heat and pressure are preferably within a range in which the integrated fibers are separated after the next cutting step. In addition, "pressing while heating" means that the heating process and the pressurizing process are preferably performed at the same time, but the heating process and the pressurizing process may be performed later, such as when the pressurizing process is performed in a state where preheating after the heating process remains. The pressurizing step may not be performed simultaneously. Further, the integrated material is not limited to a sheet shape, and the shape is not particularly limited as long as the following cutting process can be performed appropriately. Moreover, the directions in which the fibers are arranged may not be exactly the same direction, and may be substantially the same direction.

When the cross-sectional shape of the fibrous material obtained in the fibrillation step is circular, the fibrous material is partially or entirely deformed by applying pressure while being heated in the integration step, resulting in a polygonal cross-sectional shape. becomes. Thereby, an integrated material in which fibrous materials having a polygonal cross section are integrated can be produced.

Preferably, in the cutting step, the integrated material produced in the integrating step is continuously cut to produce a cut product. As a means of cutting, we use a cutting device such as the guillotine method in which both the upper and lower blades are blades, a cutting device called the push cutting method in which the lower plate and upper blade are used to cut, and a CO2 laser. A cutting device or the like for cutting can be used. These cutting devices can be used to cut so as to have cut surfaces perpendicular to the longitudinal direction of the fibers forming the unitary material. The cutting width of the cutting device is preferably 5.0 μm or more and 100.0 μm or less. The cutting speed of the cutting device is not particularly limited, but is preferably 10 spm (shots per minute) or more and 1000 spm or less.

In the stirring step, it is preferable to stir the cut material produced in the cutting step and surface-melt it by mechanical friction to produce the columnar body. Examples of the stirring method include, but are not limited to, various spherical methods, such as a method of colliding cut objects with each other and a method of colliding a material other than the cut objects with the cut objects. The rotation speed during stirring is preferably 500 rpm or more and 10000 rpm or less. Rotation time during stirring is preferably 1 minute or more and 60 minutes or less. Through this step, the peripheral region of the first surface and the peripheral region of the second surface can be produced.

In these processes, since the cutting process is performed after fixing the position and direction of the fibers by making the fibers into an integrated material in the integration process, it is possible to make the cutting width and cutting direction of the three-dimensional modeling resin uniform. , a column of uniform shape can be obtained. That is, in conventional methods such as fixing fibers with a movable clamp and moving them toward a cutting means to cut the resin fibers to obtain powder, the fibers are not sufficiently fixed, and therefore, during cutting, the fibers are not sufficiently fixed. Variations in the cut width and cut direction occur due to movement of the fibers in the . Variations in the cutting width and cutting direction produce a large number of cut products with different sizes and shapes. Also, for example, a large number of powders having unexpected shapes are produced, such as a cut product formed by cutting a columnar resin obliquely as shown in the schematic diagram of FIG. 4 . When such a cut product is used, the three-dimensional shape is not symmetrical, so even if the stirring treatment is performed, it is not possible to obtain a large number of columns having a shape in which one of the end faces covers a part of the side surface. It is difficult. In addition, if the size of the cut material is uneven, the cut material receives an excessive force during the stirring process and becomes flattened. Therefore, in order to make the content of the pillars (based on the number) 50% or more, it is preferable to go through the above-mentioned fibrillation process, integration process, cutting process, and stirring process, and by applying pressure while heating. It is more preferable to pass through the integration process of integrating in a sheet form.

<<Use of powder>>
The powders of the present embodiments have a proper balance of parameters such as particle size, particle size distribution, heat transfer properties, melt viscosity, bulk density, flowability, melt temperature, and recrystallization temperature, and can be used in SLS, SMS, It is suitably used in various three-dimensional modeling methods using powder such as the MJF (Multi Jet Fusion) method or the BJ (Binder Jetting) method. The powder of the present embodiment is also suitably used in applications such as surface contracting agents, spacers, lubricants, paints, grindstones, additives, secondary battery separators, foods, cosmetics, and clothes. Furthermore, it may be used as a material used in fields such as automobiles, precision equipment, semiconductors, aerospace, and medicine, and as a metal substitute material.

<<Production equipment for three-dimensional objects>>
The three-dimensional object manufacturing apparatus of the present embodiment includes layer forming means for forming a layer containing the three-dimensional object forming powder, and melting means for melting the layer by electromagnetic irradiation. Including other means.

Examples of layer forming means include rollers, blades, brushes, etc., or combinations thereof.

Electromagnetic radiation sources as melting means include, for example, _CO2 lasers, infrared radiation sources, microwave generators, radiant heaters, LED lamps, etc., or combinations thereof.

Here, an apparatus for manufacturing a three-dimensional object using the three-dimensional modeling powder described above will be described with reference to FIG. 5 . FIG. 5 is a schematic diagram showing a three-dimensional object manufacturing apparatus according to one embodiment of the present invention.

As shown in FIG. 5, the modeling apparatus 1 includes a supply tank 11 as an example of a storage means for storing the resin powder P for modeling, a roller 12 for supplying the resin powder P stored in the supply tank 11, and a roller 12 The laser scanning space 13 where the resin powder P supplied by is arranged and scanned by the laser L, the electromagnetic irradiation source 18 which is the irradiation source of the laser L as an electromagnetic ray, and the laser L irradiated by the electromagnetic irradiation source 18 It has a reflector 19 that reflects it to a predetermined position in the laser scanning space 13 . The modeling apparatus 1 also has heaters 11H and 13H for heating the resin powder P contained in the supply tank 11 and the laser scanning space 13, respectively.

While the electromagnetic irradiation source 18 is irradiating the laser L, the reflecting surface of the reflecting mirror 19 moves based on the two-dimensional data of the 3D (three-dimensional) model. The two-dimensional data of the 3D model indicates each cross-sectional shape obtained by slicing the 3D model at predetermined intervals. As a result, the reflection angle of the laser L is changed, so that the laser L is selectively irradiated to the portion indicated by the two-dimensional data in the laser scanning space 13 . The resin powder at the laser L irradiation position is melted and sintered to form a layer. That is, the electromagnetic irradiation source 18 functions as layer forming means for forming each layer of the modeled object from the resin powder P. As shown in FIG.

Pistons 11P and 13P are provided in the supply tank 11 and the laser scanning space 13 of the modeling apparatus 1, respectively. The pistons 11P and 13P move the supply tank 11 and the laser scanning space 13 upward or downward with respect to the stacking direction of the modeled object when the layers are completely modeled. As a result, it becomes possible to supply new resin powder P to be used for modeling a new layer from the supply tank 11 to the laser scanning space 13 .

The modeling apparatus 1 selectively melts the resin powder P by changing the irradiation position of the laser using the reflecting mirror 19, but the present invention is not limited to such an embodiment. The powder of the present embodiment is also suitably used in a selective mask sintering (SMS) type modeling apparatus. In the SMS method, for example, part of the resin powder is masked with a shielding mask, electromagnetic rays are irradiated, and electromagnetic rays such as infrared rays are irradiated to the unmasked portion, and the resin powder is selectively melted. do. When the SMS process is used, the resin powder P preferably contains at least one heat absorbing agent that enhances infrared absorption properties, or a dark substance. Examples of heat absorbing agents or dark substances include carbon fibers, carbon black, carbon nanotubes, and cellulose nanofibers. As for the SMS process, for example, the one described in US Pat. No. 6,531,086 can be preferably used.

<<Method for manufacturing three-dimensional object>>
In the method for producing a three-dimensional object according to the present embodiment, the layer forming step of forming the layer containing the three-dimensional object forming powder and the melting step of melting the layer by electromagnetic irradiation are repeated. including the steps of

The layer forming step includes, for example, a step of forming a layer using a roller, blade, brush, etc., or a combination thereof.

Melting processes include, for example, melting with electromagnetic radiation sources such as _CO2 lasers, infrared radiation sources, microwave generators, radiant heaters, LED lamps, etc., or combinations thereof.

FIG.6 and FIG.7 is a conceptual diagram for demonstrating the manufacturing method of a three-dimensional molded article. A method for manufacturing a three-dimensional object using the modeling apparatus 1 will be described with reference to FIGS. 6 and 7. FIG.

The resin powder P stored in the supply tank 11 is heated by the heater 11H. The temperature of the supply tank 5 is preferably as high as possible below the melting point of the resin particles P from the viewpoint of suppressing warping when the resin particles P are melted by laser irradiation. It is preferable that the melting point of the resin powder P is lower than the melting point of the resin powder P by 10° C. or more from the point of view of prevention. As shown in (A) of FIG. 6, the engine of the modeling apparatus 1 drives the roller 12 to supply the resin powder P in the supply tank 5 to the laser scanning space 13 to level the ground as an example of the supply process. to form a powder layer with a thickness T corresponding to one layer. The resin powder P supplied to the laser scanning space 13 is heated by the heater 13H. The temperature of the laser scanning space 13 is preferably as high as possible in terms of suppressing warping when the resin particles P are melted by laser irradiation. It is preferably lower than the melting point of the resin powder P by 5°C or more.

The engine of the modeling apparatus 1 receives inputs of a plurality of two-dimensional data generated from the 3D model. As shown in FIG. 6B, the engine of the modeling apparatus 1 moves the reflecting surface of the reflecting mirror 19 based on the two-dimensional data closest to the bottom surface among the plurality of two-dimensional data, and moves the electromagnetic irradiation source. 18 is irradiated with a laser. The output of the laser is not particularly limited and is appropriately selected according to the purpose, but is preferably 10 watts or more and 150 watts or less. The laser irradiation melts the resin powder P at the position corresponding to the pixel indicated by the two-dimensional data on the bottom side of the powder layer. When the laser irradiation is completed, the melted resin is cured to form a sintered layer having a shape indicated by the two-dimensional data on the bottom side.

The thickness T of the sintered layer is not particularly limited, but the average value is preferably 10 μm or more, more preferably 50 μm or more, and even more preferably 100 μm or more. The thickness T of the sintered layer is not particularly limited, but the average value is preferably less than 200 μm, more preferably less than 150 μm, and even more preferably less than 120 μm.

As shown in FIG. 7A, when the bottommost sintered layer is formed, the engine of the modeling apparatus 1 forms a modeling space with a thickness T corresponding to one layer in the laser scanning space 13. , the piston 13P lowers the laser scanning space 13 by the thickness T of one layer. Further, the engine of the modeling apparatus 1 raises the piston 11P so that new resin powder P can be supplied. Subsequently, as shown in FIG. 7A, the engine of the modeling apparatus 1 drives the rollers 12 to supply the resin powder P in the supply tank 5 to the laser scanning space 13 to level the ground. A powder layer having a layer thickness T is formed.

As shown in FIG. 7B, the engine of the modeling apparatus 1 moves the reflecting surface of the reflecting mirror 19 based on the two-dimensional data of the second layer from the bottom side among the plurality of two-dimensional data. , causes the electromagnetic radiation source 18 to irradiate the laser. As a result, the resin powder P at the positions corresponding to the pixels indicated by the two-dimensional data of the second layer from the bottom side of the powder layer is melted. When the laser irradiation is completed, the melted resin is cured, and a sintered layer of the shape indicated by the two-dimensional data of the second layer from the bottom side is formed in a state of being laminated on the sintered layer closest to the bottom side. be.

The modeling apparatus 1 stacks the sintered layers by repeating the supply step and the layer forming step. When modeling based on all of the plurality of two-dimensional data is completed, a three-dimensional object having the same shape as the 3D model is obtained.

<<Three-dimensional model>>
A three-dimensional object is preferably manufactured by the three-dimensional object manufacturing method of the present invention.

Examples of the present invention will be described below, but the present invention is not limited to these examples.

(Example 1)
After stirring polybutylene terephthalate (PBT) resin (trade name: NOVADURAN 5020, manufactured by Mitsubishi Engineering-Plastics Corporation, melting point: 218°C, glass transition temperature: 43°C) at a temperature 30°C higher than the melting point, the nozzle mouth is circular. The three-dimensional modeling resin solution was stretched in a fibrous form using an extrusion machine (manufactured by The Japan Steel Works, Ltd.). The fiber was drawn 4 times to adjust the fiber diameter (diameter) to 55 μm. Thereafter, the formed fibers were aligned in the same direction and integrated into a sheet by applying a pressure of 10 MPa while heating at a temperature 50° lower than the melting point. It should be noted that the cross-sectional shape of each fiber integrated into a sheet shape was substantially polygonal. Furthermore, the sheet-like integrated fibers are adjusted to a cutting width of 50 μm and a cutting speed of 280 spm (shots per minute) using a push-cutting type cutting device (NJ series 1200 type, manufactured by Ogino Seiki Seisakusho Co., Ltd.). and judged. After that, in order to melt the surface by mechanical friction, the resulting cut material was processed at a rotation speed of 9000 rpm for 20 minutes using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) to obtain resin powder for three-dimensional modeling. This was used as the resin powder for stereolithography of Example 1.

(Example 2)
In Example 1, the resin powder for stereolithography of Example 2 was prepared in the same manner as in Example 1, except that the time for stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was changed from 20 minutes to 10 minutes. got

(Example 3)
In Example 1, the resin powder for stereolithography of Example 3 was prepared in the same manner as in Example 1, except that the time for stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was changed from 20 minutes to 5 minutes. got

(Example 4)
In Example 3, the resin powder for three-dimensional modeling of Example 4 was prepared in the same manner as in Example 1, except that the rotation speed for the stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was changed from 9000 rpm to 6000 rpm. got

(Example 5)
In Example 3, the resin powder for three-dimensional modeling of Example 5 was prepared in the same manner as in Example 1, except that the rotation speed for the stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was changed from 9000 rpm to 3000 rpm. got

(Example 6)
After stirring polybutylene terephthalate (PBT) resin (trade name: NOVADURAN 5020, manufactured by Mitsubishi Engineering-Plastics Corporation, melting point: 218°C, glass transition temperature: 43°C) at a temperature 30°C higher than the melting point, the nozzle mouth is circular. The three-dimensional modeling resin solution was stretched in a fibrous form using an extrusion machine (manufactured by The Japan Steel Works, Ltd.). The fiber was drawn 4 times to adjust the fiber diameter (diameter) to 55 μm. After that, the formed fibers were arranged side by side in the same direction, and fixed in ice by applying water and then cooling. Furthermore, the fibers fixed in the ice were adjusted to a cutting width of 50 μm and a cutting speed of 280 spm (shots per minute) using a push cutting type cutting device (manufactured by Ogino Seiki Seisakusho Co., Ltd., NJ series 1200 type). I cut. After that, in order to melt the surface by mechanical friction, the resulting cut material was processed at a rotation speed of 9000 rpm for 20 minutes using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) to obtain resin powder for three-dimensional modeling. This was used as the resin powder for stereolithography of Example 6.

(Example 7)
In Example 6, except that the rotation speed for stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was changed from 9000 rpm to 3000 rpm, and the time for stirring treatment was changed from 20 minutes to 5 minutes. Similarly, a resin powder for stereolithography of Example 7 was obtained.

(Example 8)
Same as Example 1, except that polybutylene terephthalate (PBT) resin was changed to polyacetal (POM) resin (trade name: Iupital F10-01, manufactured by Mitsubishi Engineering-Plastics Corporation, melting point: 175°C). Then, a three-dimensional modeling resin powder of Example 8 was obtained.

(Example 9)
In Example 1, polybutylene terephthalate (PBT) resin was changed to polyamide 12 (PA12) resin (trade name: Daiamide L2121, manufactured by Daicel-Evonik, melting point: 172 ° C.). A three-dimensional modeling resin powder of Example 9 was obtained.

(Example 10)
In Example 1, polybutylene terephthalate (PBT) resin was changed to polyether ether ketone (PEEK) resin (trade name: HT P22PF, manufactured by VICTREX, melting point: 343°C, glass transition temperature: 143°C). In the same manner as in Example 1, a three-dimensional modeling resin powder of Example 10 was obtained.

(Example 11)
In Example 1, polybutylene terephthalate (PBT) resin was changed to polypropylene (PP) resin (trade name: Novatec MA3, manufactured by Japan Polypropylene Corporation, melting point: 180°C, glass transition temperature: 0°C). In the same manner as in Example 1, a three-dimensional modeling resin powder of Example 11 was obtained.

(Example 12)
After stirring polybutylene terephthalate (PBT) resin (trade name: NOVADURAN 5020, manufactured by Mitsubishi Engineering-Plastics Corporation, melting point: 218°C, glass transition temperature: 43°C) at a temperature 30°C higher than the melting point, the nozzle mouth is circular. The three-dimensional modeling resin solution was stretched in a fibrous form using an extrusion machine (manufactured by The Japan Steel Works, Ltd.). The fiber was drawn 4 times to adjust the fiber diameter (diameter) to 55 μm. After that, the formed fibers were aligned in the same direction and fixed with a movable clamp. Furthermore, the fiber fixed by the clamp is cut by adjusting the cutting width to 50 μm and the cutting speed to 280 spm (shots per minute) using a push cutting type cutting device (manufactured by Ogino Seiki Seisakusho Co., Ltd., NJ series 1200 type). did. After that, in order to melt the surface by mechanical friction, the resulting cut material was processed at a rotation speed of 1000 rpm for 20 minutes using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) to obtain resin powder for three-dimensional modeling. This was used as the resin powder for stereolithography of Example 1.

(Comparative example 1)
A three-dimensional modeling resin powder of Comparative Example 1 was obtained in the same manner as in Example 1, except that the stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was not performed.

(Comparative example 2)
A three-dimensional modeling resin powder of Comparative Example 2 was obtained in the same manner as in Example 6, except that the stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was not performed.

(Comparative Example 3)
A three-dimensional modeling resin powder of Comparative Example 3 was obtained in the same manner as in Example 12, except that the stirring treatment using a multi-purpose mixer (manufactured by Nippon Coke Kogyo Co., Ltd.) was not performed.

Regarding the three-dimensional modeling resin powder obtained in each example and comparative example, the "powder shape" was observed in the following manner, and the "column content" and "first surface and second surface The shortest length of the outer peripheral area of the surface of the surface was measured. The results are shown in Table 1 below.

[Powder shape]
The obtained resin powder for three-dimensional modeling was photographed at a magnification of 150 using an SEM (scanning electron microscope JSM-7800FPRIME manufactured by JEOL Ltd.). The three-dimensional modeling resin powder in the SEM image obtained by photographing has a first surface, a second surface, and a side surface, and the first surface and the first surface in the range observed with the SEM A column body was judged to have a shape in which at least one of the outer peripheral regions of the two surfaces had a shape extending along the side surface in a partial region or in the entire region.

Next, the side surface of the three-dimensional modeling resin particles determined to be a columnar body is observed, and when a plurality of surfaces separated by lines (angles) in the height direction of the columnar body can be observed, the first opposing surface and the If it is determined that the second opposing surface has a substantially polygonal shape, and if a line in the height direction of the column cannot be observed and a smooth surface can be observed uniformly, the first opposing surface and the second opposing surface It was determined that the surface had a substantially circular shape (substantially perfect circular shape or substantially elliptical shape).

[Content of three-dimensional modeling particles (cylinders)]
The obtained resin powder for three-dimensional modeling was photographed at a magnification of 150 using an SEM (scanning electron microscope JSM-7800FPRIME manufactured by JEOL Ltd.). The three-dimensional modeling resin powder in the SEM image obtained by photographing has a first surface, a second surface, and a side surface, and the first surface and the first surface in the range observed with the SEM A column body was judged to have a shape in which at least one of the outer peripheral regions of the two surfaces had a shape extending along the side surface in a partial region or in the entire region.

Next, the number of resin powders for three-dimensional modeling and the number of pillars are obtained from the SEM image, and the number of pillars is divided by the number of resin powders for three-dimensional modeling and multiplied by 100. Amount (%) was calculated. When the number of resin powders for three-dimensional modeling and the number of pillars were obtained from the SEM image, only the resin powder for three-dimensional modeling and the number of pillars having the longest part of 20 μm or more were counted. In addition, the number of the three-dimensional modeling resin powders counted when calculating the content of the pillars was 100 pieces.

[Shortest Length of Peripheral Regions of First and Second Surfaces]
The obtained resin powder for three-dimensional modeling was photographed at a magnification of 150 using an SEM (scanning electron microscope JSM-7800FPRIME manufactured by JEOL Ltd.). The three-dimensional modeling resin powder in the SEM image obtained by photographing has a first surface, a second surface, and a side surface, and the first surface and the first surface in the range observed with the SEM A column body was judged to have a shape in which at least one of the outer peripheral regions of the two surfaces had a shape extending along the side surface in a partial region or in the entire region.

Next, the shortest length (μm) in the height direction of the column in the peripheral region of the first surface and the second surface was calculated in the range observed by SEM.

Regarding the three-dimensional modeling resin powder obtained in each example and comparative example, the "loose density", "volume average particle system Dv", "number average particle size Dn", and "modeled object strength” was evaluated. The results are shown in Table 2 below.

[Looseness density]
The loose density of the produced resin powder for three-dimensional modeling is measured using a bulk hydrometer (compliant with JIS Z-2504, manufactured by Kuramochi Scientific Instruments), and the measured loose density is divided by the true density of each resin to obtain the loose filling rate. (%) was obtained. In addition, the case where it was C or more was made into practical use.
(Evaluation criteria)
A: 40% or more B: 35% or more and less than 40% C: 33% or more and less than 35% D: less than 33%

[Volume average particle system Dv and number average particle diameter Dn]
The volume average particle system Dv (μm) of the obtained resin powder for three-dimensional modeling is obtained by using a particle size distribution measuring device (microtrac MT3300EXII manufactured by Microtrac Bell Co., Ltd.), using the particle refractive index of each resin powder, Measurement was performed by a dry (atmospheric) method without using a solvent.

The number average particle diameter Dn (μm) of the obtained resin powder for three-dimensional modeling was measured using a particle size distribution analyzer (F-PIA3000 manufactured by Sysmex).

Also, the volume average particle system/number average particle diameter (Dv/Dn) was calculated from the obtained volume average particle system Dv (μm) and number average particle diameter Dn (μm).

[Strength of molded object]
The obtained three-dimensional modeling resin powder was added to the supply bed of an SLS modeling apparatus (manufactured by Ricoh Co., Ltd., AM S5500P) to produce a three-dimensional model. The setting conditions were an average layer thickness 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 temperature of −3° C. from the melting point as the part bed temperature. In the SLS molding apparatus, five tensile test specimens (XY molded objects) whose long sides face the XY plane direction (the plane direction in which the roller 12 advances in FIG. 5) are placed in the center of the laser scanning space 13, Five tensile test specimens (Z shaped objects) were shaped with long sides facing in the Z-axis direction (the direction perpendicular to the plane in which the roller 12 advances in FIG. 5). The distance between each model is 5 mm or more. Tensile test specimens are ISO (International Organization for Standardization) 3167 Type 1A multi-purpose dog-bone-like test specimens (specimens have a central portion of 80 mm length, 4 mm thickness, and 10 mm width). The modeling time was set to 50 hours.

Next, using the same resin powder for three-dimensional modeling, five tensile test specimens having the same shape were molded by injection molding.

The XY model and Z model, which are tensile test specimens obtained by the SLS molding apparatus, and the tensile test specimens obtained by injection molding, were subjected to a tensile tester (Shimadzu Corporation, AGS- 5 kN) was used to measure the "tensile strength". Note that the test speed in the tensile test was constant at 50 mm/min. Moreover, the tensile strength was taken as the average value of the measured values obtained by performing the test five times on each tensile test specimen. Then, by dividing the tensile strength of the tensile test specimen obtained by the SLS molding apparatus by the tensile strength of the tensile test specimen obtained by injection molding, the tensile strength of the tensile test specimen obtained by the SLS molding apparatus is obtained. evaluated. Note that evaluations of both the XY-molded article and the Z-molded article were considered to be practicable when 60% or more of the injection-molded article was evaluated.

1 modeling device 11 supply tank 11H heater 11P piston 12 roller 13 laser scanning space 13H heater 13P piston 18 electromagnetic irradiation source 19 reflecting mirror 21 column 22 first surface (an example of an end surface)
22a first opposing surface 22b outer peripheral region 23 of first surface second surface (an example of an end surface)
23a Second opposing surface 23b Peripheral region 24 of second surface Side surface

WO2017/112723

Claims (14)

A columnar shape having end faces and side faces,
The end face is
comprising a first surface and a second surface;
at least the first surface is a first opposing surface;
The first opposing surface has a shape extending along the side surface,
a peripheral region that is a surface continuous with the first opposing surface,
The three-dimensional shaping particles, wherein the peripheral region covers a part of the side surface . A solid forming powder comprising the solid forming particles according to claim 1 . 3. The powder for stereolithography according to claim 2 , wherein in the region where the end face of the particle for stereolithography covers the side surface, the length of the shortest portion in the height direction of the columnar shape is 1 μm or more. 4. The three-dimensional modeling powder according to claim 2 , wherein the content of the three-dimensional modeling particles (number basis) is 50% or more of the three -dimensional modeling powder. The solid forming powder according to any one of claims 2 to 4 , wherein the content of the solid forming particles (number basis) is 70% or more of the solid forming powder. The powder for three-dimensional modeling according to any one of claims 2 to 5, wherein the end faces of the particles for three-dimensional modeling have a substantially perfect circular shape, a substantially elliptical shape, or a substantially polygonal shape. 7. The solid forming powder according to any one of claims 2 to 6 , comprising the solid forming particles having a substantially prismatic shape. 8. The three-dimensional modeling powder according to claim 7 , wherein the content (based on the number) of the three-dimensional modeling particles having a substantially prismatic shape is 40% or more of the three-dimensional modeling powder. 9. The powder for stereolithography according to any one of claims 2 to 8 , wherein the particles for stereolithography contain at least one selected from polybutylene terephthalate, polyamide, polyacetal, and polyetheretherketone. Storage means for storing the three-dimensional modeling powder according to any one of claims 2 to 9 , layer forming means for forming a layer containing the three-dimensional modeling powder, and melting by electromagnetic irradiation of the layer A three-dimensional object manufacturing apparatus having a melting means for melting. A method for producing a three-dimensional object, which repeats a layer forming step of forming a layer containing the powder for three-dimensional modeling according to any one of claims 2 to 9 , and a melting step of melting the layer by electromagnetic irradiation. A method for producing a three-dimensional modeling powder according to any one of claims 2 to 9 ,
a fiberization step of forming a fibrous material from the material constituting the three-dimensional modeling powder;
an integration step of integrating a plurality of fibrous materials arranged in the same direction to form an integrated material;
a cutting step of cutting the integrated material to obtain a cut product;
A stirring step of stirring the cut material;
A method for producing a three-dimensional modeling powder having A method for producing a powder for three-dimensional modeling, comprising:
a fiberization step of forming a fibrous material from the material constituting the three-dimensional modeling powder;
an integration step of integrating a plurality of fibrous materials arranged in the same direction to form an integrated material;
a cutting step of cutting the integrated material to obtain a cut product;
A stirring step of stirring the cut material;
wherein the integrating step includes heating and pressing a plurality of fibrous materials arranged in the same direction to integrate them to form the integrated material. A columnar shape having end faces and side faces,
the end surface includes a first surface and a second surface;
At least the first surface includes a first opposing surface, and an outer peripheral region having a shape extending the first opposing surface along the side surface and being a surface continuous with the first opposing surface. including
The peripheral region is a particle covering a portion of the side surface .

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