JP2019188744A - Composition for three-dimensional printer - Google Patents

Abstract

To provide a composition for a three-dimensional printer, upon molding a molded article (laminated structure) using a three-dimensional printer of a thermofusion lamination system with an inorganic powder-containing composition as raw material, capable of reducing stringing and obtaining a molded article having satisfactory appearance, and in which deformation is hard to be generated upon degreasing the molded article.SOLUTION: A composition for a three-dimensional printer comprises: inorganic powder (A); and an organic binder (B). The organic binder (B) includes: a thermoplastic resin (B1) having a weight average molecular weight of 10,000 or higher; and an organic compound (B2) having a molecular wight or a weight average molecular weight of 8,000 or lower. The mass ratio between the inorganic powder (A) and the organic binder (B) satisfies (A)/(B)=100/7 to 100/30, and the mass ratio between the thermoplastic resin (B1) and the organic compound (B2) satisfies (B1)/(B2)=0.2 to 1.4.SELECTED DRAWING: None

Description

  The present invention relates to a composition suitable for use in a three-dimensional printer.

  A 3D printer that laminates a three-dimensional model based on three-dimensional digital data is expected to be put to practical use in various fields. As a method of manufacturing a three-dimensional modeled object with a 3D printer, an optical modeling method, a powder sintering lamination method, a hot melt lamination method, and an ink jet method are mainly known.

  In FDM (Fused Deposition Modeling), melted resins are laminated one by one using filaments made of thermoplastic resins such as PLA (polylactic acid) and ABS (acrylonitrile-butadiene-styrene) as raw materials. It is common to obtain a three-dimensional structure made of a thermoplastic resin by cooling and solidifying.

  If you want to manufacture metal or ceramic products with a three-dimensional printer instead of products made of thermoplastic resin, a method of directly sintering with a high-power laser or a method of dispersing filler in a photo-curing resin is generally adopted. Has been. However, these methods have a problem that the apparatus is expensive and a lamination speed is low.

On the other hand, using a compound made by adding ceramics or metal powder to a thermoplastic resin, a model is manufactured with a three-dimensional printer, and then degreased and sintered to obtain a metal or ceramic product. Has been proposed (Patent Document 1).
In addition, as a three-dimensional printer capable of producing a model using such a compound (pellet), a three-dimensional printer having an extrusion device has been devised (Patent Document 2).

JP 2000-144205 A WO2015 / 129733

  According to the method of Patent Document 1, after using a compound containing inorganic powder as a raw material to produce a molded article using a hot melt lamination type (FDM type) three-dimensional printer, powder injection molding (PIM) It is possible to obtain a metal or ceramic product by performing degreasing and sintering (sintering), which is generally performed in, so it is possible to solve the problem that the device is expensive and the lamination speed is slow It is.

  However, if a compound similar to the conventional PIM is used in a method of manufacturing a three-dimensional model using a three-dimensional printer and then performing degreasing and sintering to obtain a metal or ceramic product, stringing occurs. There was a problem that it was easy. More specifically, after a desired three-dimensional structure is layered and formed by discharging a molten resin from the nozzle by an FDM type three-dimensional printer, when the nozzle is moved to the next stacking position, the post-modeling 3 There is a problem that stringing occurs between the three-dimensional structure and the moving nozzle tip, and a whisker-like burr adheres to the three-dimensional structure, resulting in a poor appearance. In addition, when trying to improve this stringing, there is a problem that a problem easily occurs during degreasing.

  Therefore, according to the present invention, when a three-dimensional printer using an FDM printer system is used as a raw material for a composition containing an inorganic powder and an organic binder, a shaped article having a good appearance can be obtained by reducing stringing. It is an object of the present invention to provide a composition for a three-dimensional printer that can be easily deformed when the organic binder is removed (degreased) from the shaped article.

  As a result of repeated studies to solve the above problems, the present inventor mixed a specific organic binder at a specific ratio with an inorganic powder, so that the stringiness (threading) can be improved even when used in a three-dimensional printer. Have succeeded in obtaining a composition that is less prone to problems (deformation, cracks, etc.) during degreasing.

The composition (compound) for a three-dimensional printer of the present invention capable of solving the above-mentioned problems is
A composition for a three-dimensional printer containing (A) an inorganic powder and (B) an organic binder,
The organic binder (B) contains (B1) a thermoplastic resin having a weight average molecular weight of 10,000 or more, and (B2) an organic compound having a molecular weight or weight average molecular weight of 8000 or less,
The mass ratio of the inorganic powder (A) and the organic binder (B) is (A) / (B) = 100/7 to 100/30,
A mass ratio of the thermoplastic resin (B1) and the organic compound (B2) is (B1) / (B2) = 0.2 to 1.4.

Preferable examples of the inorganic powder (A) include metal oxide powders having an average particle diameter (D ₅₀ ) of 0.1 to 1.0 μm.

Another preferred example of the inorganic powder (A) is a metal powder having an average particle diameter (D ₅₀ ) of 3 to 10 μm.

  Moreover, it is preferable that the said thermoplastic resin (B1) is a mixture of two or more types of thermoplastic resins.

  Preferred examples of the organic compound (B2) include waxes and higher fatty acids.

Further, the present invention is a method for producing a product made of ceramics, cermet, or metal,
Using the composition for a three-dimensional printer, it includes a step of forming a laminated structure by an FDM type three-dimensional printer, a step of degreasing the laminated structure, and a step of sintering.

  Since the composition for a three-dimensional printer of the present invention has low stringiness, a laminated structure that is less prone to beard-like burrs and that has an excellent appearance in the process of forming a laminated structure with an FDM three-dimensional printer. Obtainable. Further, since deformation, cracks, blisters and the like hardly occur in the degreasing step, a ceramic product or the like can be obtained by using a degreasing / sintering step similar to PIM. For this reason, it becomes possible to obtain a product having a complicated shape made of ceramics or the like, which is a difficult-to-work material, based on the three-dimensional CAD data.

Examples of the inorganic powder (A) that can be used in the composition for a three-dimensional printer of the present invention include sinterable powders such as metal powders, ceramic powders, and cermet powders.
Specifically, examples of the metal powder include powders of iron-based alloys such as pure iron, iron-nickel, iron-cobalt, iron-silicon, and stainless steel, tungsten, tungsten carbide, aluminum alloy, copper, and copper alloy. Can be mentioned. Ceramic powders include oxides such as Al ₂ O ₃ , BeO and ZrO ₂ , carbides such as TiC, ZrC and B ₄ C, borides such as CrB and ZrB _2, and nitrides such as TiN and ZrN. Can be mentioned. Examples of the cermet powder include Al ₂ O ₃ —Fe, TiC—Ni, TiC—Co, and B ₄ C—Fe.
Particularly preferred examples of the inorganic powder (A) used in the present invention include metal oxides such as alumina (Al ₂ O ₃ ) and zirconia (ZrO ₂ ). The zirconia may be yttria partially stabilized zirconia. In particular, a metal oxide powder having an average particle diameter (D ₅₀ ) of 0.1 to 1.0 μm, more preferably 0.1 to 0.8 μm is preferable.

The organic binder (B) used in the present invention is a thermoplastic resin (B1) having a weight average molecular weight of 10,000 or more, preferably 20,000 or more, particularly preferably 40,000 or more, and a molecular weight or weight average. An organic compound (B2) having a molecular weight of 8,000 or less, preferably 4,000 or less, and particularly preferably 3,500 or less is included. By using (B1) and (B2) in combination, degreasing does not proceed at once, and removal of the organic binder proceeds stepwise, so that deformation during degreasing can be suppressed.
The weight average molecular weight can be determined using gel permeation chromatography (GPC).

  The thermoplastic resin (B1) preferably has a softening point of 65 ° C. or higher, and more preferably 70 ° C. or higher. The softening point (Vicat softening temperature) can be measured by the JIS K7206 B50 method.

  Examples of the thermoplastic resin (B1) include polyethylene (PE), polypropylene (PP), polyacetal (POM), polyamide, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polystyrene (PS), and polycarbonate (PC). Acrylonitrile-styrene (AS), acrylonitrile-butadiene-styrene (ABS), acrylic resins such as polymethyl methacrylate (PMMA) resin, and ethylene-vinyl acetate copolymer (EVA). The melting point of the thermoplastic resin (B1) is preferably 170 ° C. or lower. More preferable examples of the resin include PP, PS, POM, acrylic resin, and EVA. From the viewpoint of reducing stringiness, it is preferable to use an acrylic resin.

The thermoplastic resin (B1) may be a single type or a plurality of types, but it is more preferable to use a plurality of resins having different rheological properties. By using two or more types of thermoplastic resins having different rheological properties, defects (particularly cracks and blisters) at the time of degreasing can be sufficiently suppressed.
Specifically, a thermoplastic resin (for example, PP, PS, POM, etc.) having a flow value at 180 ° C. of 0.002 to 0.08, more preferably 0.003 to 0.07, and a flow at 180 ° C. It is preferable to use together a thermoplastic resin having a value of 0.09 or more, more preferably 0.10 or more (for example, an acrylic resin having a flow value at 180 ° C. of 0.10 to 0.20). The thermoplastic resin having a flow value at 180 ° C. of 0.09 or more includes a resin whose fluidity becomes too high at 180 ° C. and an accurate value cannot be measured.
The flow value can be determined using a flow tester (for example, a constant test force extrusion type capillary rheometer sold by Shimadzu Corporation) as shown in the section of the examples.

  As a particularly preferable example in the case of using a plurality of thermoplastic resins (B1), when the inorganic powder is a metal oxide powder, a combination of an acrylic resin and PS can be mentioned, and when the inorganic powder is a metal powder, acrylic is used. A combination of a resin and POM can be mentioned. The mass ratio of the acrylic resin to PS is preferably 10 to 130, more preferably 15 to 70, and particularly preferably 20 to 50 with respect to the acrylic resin 100. The mass ratio of the acrylic resin and POM is preferably 80 to 180, more preferably 100 to 150, and particularly preferably 110 to 140 with respect to the acrylic resin 100. In addition to the acrylic resin and PS or POM, other resins (EVA, PP, etc.) may be used. When using other resins, when the inorganic powder is a metal oxide powder, the total mass of the other resins is preferably 80 or less, and preferably 60 or less, with respect to the mass 100 of the acrylic resin. Is more preferable. When the inorganic powder is a metal powder, the total mass of the other resins is preferably 80 or less, and more preferably 60 or less, with respect to the total mass 100 of the acrylic resin and POM.

As a particularly preferred example of the acrylic resin, as described in JP 2000-303103 A,
An ethylene-vinyl acetate copolymer or an ethylene-ethyl acrylate copolymer;
A (meth) acrylate monomer alone or a mixture of a (meth) acrylate monomer and a styrene monomer and a polymerization initiator is dispersed in an aqueous medium containing a dispersant. A composite acrylic resin obtained by suspension polymerization is exemplified.
Moreover, as an acrylic resin, the polymer of the (meth) acrylic acid ester which is ester of the C1-C8 alcohol of (meth) acrylic acid can be used. Specific examples of such (meth) acrylic acid ester monomers include, for example, n-alkyl (meth) acrylates having 1 to 8 carbon atoms in the alkyl group, isopropyl (meth) acrylate, isobutyl (meth) acrylate, Examples thereof include t-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, and 2-ethoxyethyl (meth) acrylate. Among these, an n-alkyl (meth) acrylate having 1 to 4 carbon atoms of an alkyl group such as n-butyl (meth) acrylate, isopropyl (meth) acrylate, and isobutyl (meth) acrylate are particularly preferable. Or two or more of them may be used in combination.

  As PS, one having a weight average molecular weight of about 100,000 to 300,000 is preferably used, and one having about 15 to 250,000 is more preferable. As the POM, those having a weight average molecular weight of about 1 to 70,000 are preferable, and those having a weight average molecular weight of about 2 to 50,000 are more preferable.

  As the organic compound (B2) having a weight average molecular weight or molecular weight of 8000 or less, amorphous polyolefins, waxes, lubricants, plastics are provided in that they give good fluidity to a mixture with inorganic powder and are excellent in thermal decomposability. Although an agent etc. are preferable, it is not limited to these, Other additives, such as antioxidant, can also be used.

As the amorphous polyolefin, those having a weight average molecular weight of 1000 to 8000, more preferably about 2000 to 4000 can be used.
As the waxes, any of synthetic and natural types can be used, and specific examples thereof include paraffin wax, microcrystalline wax, polyethylene wax, beeswax, carnauba wax, montan wax, polyalkylene glycol and the like.
Specific examples of the lubricant include fatty acids and derivatives of fatty acids such as esters, amides, metal salts, and the like, and preferably higher fatty acids such as stearic acid.
Specific examples of the plasticizer include, for example, phthalic acid esters (dibutyl phthalate, dioctyl phthalate, 4-cyclohexene-1,2-dicarboxylic acid bis (2-ethylhexyl), 1,2-cyclohexanedicarboxylic acid diisononyl ester, etc.) , Phosphoric acid ester, fatty acid ester (monostearic acid sorbitan ester, etc.).
Moreover, as a specific example of antioxidant, a phenolic antioxidant is mentioned, for example. Specific examples thereof include 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 4,4′-butylidenebis (6-tert-butyl-m-cresol), bis [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionic acid] [ethylenebis (oxyethylene)], bis [3- (3-tert-butyl-4-hydroxy-5-methylphenylpropiate) On acid] (2,4,8,10-tetraoxaspiro [5,5] undecane-3,9-diyl) bis (2,2-dimethyl-2,1-ethanediyl), pentaerythritol = tetrakis [3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate] and the like.

  Examples of organic compounds corresponding to (B2) other than waxes, lubricants, plasticizers, and antioxidants include additives such as metal deactivators, ultraviolet absorbers, and nucleating agents.

  In particular, as the organic compound (B2), an amorphous polyolefin having a weight average molecular weight of 1000 to 8000 and an organic compound having a molecular weight of 150 to 1000, particularly 200 to 800 (the waxes, lubricants, plasticizers, etc.) may be used in combination. preferable.

  Moreover, it is preferable to use the organic compound (B2) having a heating loss starting point of 150 ° C. or lower. The starting point of heat loss can be determined by the thermogravimetric method defined in JIS K7120. By blending the organic compound (B2) that begins to lose weight at 150 ° C. or lower, the binder content at 150 ° C. or higher can be reduced, the plasticity of the molded body can be reduced, and deformation can be prevented.

In the composition for a three-dimensional printer of the present invention, the mass ratio of the inorganic powder (A) and the organic binder (B) is suitably in the range of (A) / (B) = 100/7 to 100/30. is there. When the mass of (B) is less than 7 with respect to the mass of 100 of (A), the flow value is low and modeling becomes difficult. On the other hand, if the mass of (B) exceeds 30, the stringiness increases and defects such as deformation tend to occur during degreasing.
When the inorganic powder (A) is a ceramic powder (for example, a metal oxide powder such as alumina or zirconia), a more preferable mass ratio is (A) / (B) = 100/10 to 100/30, particularly 100 / 15-100 / 25 is preferable.
When the inorganic powder (A) is a metal powder (for example, stainless steel or the like), a more preferable mass ratio is (A) / (B) = 100/7 to 100/20, particularly 100/7 to 100 /. 15 is preferred.

In the composition for a three-dimensional printer of the present invention, the mass ratio of the thermoplastic resin (B1) to the organic compound (B2) is suitably (B1) / (B2) = 0.2 to 1.4. . When (B1) / (B2) is less than 0.2, the stringing property is low, but problems are likely to occur during degreasing. On the other hand, when (B1) / (B2) exceeds 1.4, deformation and cracks during degreasing can be suppressed, but stringing properties are improved.
When the inorganic powder (A) is a ceramic powder (for example, a metal oxide powder such as alumina or zirconia), a more preferable mass ratio of (B1) to (B2) is (B1) / (B2) = 0.4. To 1.35, particularly preferably 0.5 to 1.0.
When the inorganic powder (A) is a metal powder (for example, stainless steel), the more preferable mass ratio of (B1) and (B2) is (B1) / (B2) = 0.8 to 1.4. In particular, 1.0 to 1.3 is preferable.

  The method for producing the composition for a three-dimensional printer of the present invention is prepared by melt-kneading the inorganic powder (A) and the organic binder (B). Although not particularly limited, an example of a preferable form is a pressure kneader. Various kneaders such as a batch type such as a double-arm kneader kneader and a Banbury kneader, and a continuous type such as a single-screw or twin-screw kneading extruder can be used.

  Although the shape of the composition for three-dimensional printers of this invention is not specifically limited, As a preferable form, the form of the pellet form used by PIM can be mentioned. Although it does not specifically limit, As an example of a preferable form, what was pelletized with the hot-cut type pelletizer which cuts the extruded melt after kneading | mixing in the pellet form in air with a rotary cutter is mentioned.

  In addition, the present invention uses the composition for a three-dimensional printer (a composition highly filled with inorganic powder) to form a laminated structure with an FDM three-dimensional printer, and then degrease and sinter, Provided is a method for manufacturing a product made of ceramics, cermet, or metal.

  Examples of the FDM type three-dimensional printer include a cylinder, a screw, a gear pump, an extrusion device having a nozzle, and a nozzle of the extrusion device as disclosed in Patent Document 2 (WO2015 / 129733). Controlling the discharge of the resin from the nozzle in the table device positioned opposite to the extrusion device, and in the X-axis, Y-axis, and Z-axis directions with respect to the reference plane of the extrusion device and / or the table device It is possible to use a three-dimensional printer provided with a control device for controlling the movement of the image.

  The degreasing / sintering conditions may be the same as those for PIM degreasing / sintering, and can be set as appropriate according to the type of inorganic powder contained in the composition. For example, when the inorganic powder is zirconia (yttria-stabilized zirconia or the like) or alumina, the temperature is raised to about 450 to 550 ° C. at a temperature rising rate of 10 to 20 ° C./h, and then degreasing is performed. Sintering can be performed by raising the temperature to 1300 to 1600 ° C. at a rate of ° C./h. When the inorganic powder is a metal, degreasing is performed by raising the temperature to about 450 to 550 ° C. at a temperature rising rate of 10 to 20 ° C./h in an inert gas atmosphere, and then a temperature of 1300 to 1400 at a temperature rising rate of 40 to 60 ° C./h. Sintering can be performed by raising the temperature to 1400 ° C.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to an Example.

[material]
The following substances were used as (A) inorganic powder, (B1) thermoplastic resin, and (B2) organic compound. The flow value was measured using a flow tester “CFD-500D” manufactured by Shimadzu Corporation, with a die set with a diameter of 1 mm × length of 1 mm, a load of 0.98 MPa, and a flow per unit time of 180 ° C. It was determined by measuring the amount (ml / sec). In the case where the fluidity was too high at 180 ° C. and an accurate value could not be measured, the flow temperature was obtained by changing the set temperature to 140 ° C.

(A) Yttria partially stabilized zirconia powder containing 3 mol% of inorganic powder Y ₂ O ₃ (BET specific surface area is 15 m ² / g; average particle diameter D ₅₀ is 0.15 μm)
Alumina powder (BET specific surface area is 6 m ² / g; average particle diameter D ₅₀ is 0.52 μm)
Stainless powder (SUS316L) (average particle diameter D ₅₀ is 7.05Myuemu, tap density 4.6 g / cm ³⁾

(B1) Thermoplastic resin / PP (weight average molecular weight 240,000, 180 ° C. flow value 0.051 ml / sec, melting point 163 ° C.)
PS (weight average molecular weight 190,000, 180 ° C flow value 0.064ml / sec, deflection temperature under load 70 ° C)
Acrylic resin (copolymer of n-butyl methacrylate and methyl methacrylate, weight average molecular weight 50,000, 180 ° C. flow value 0.110 ml / sec)
EVA (weight average molecular weight 70,000, 140 ° C flow rate 0.30 ml / sec, melting point 68 ° C)
・ POM (weight average molecular weight 50,000, 180 ° C. flow value 0.003 ml / sec, melting point 165 ° C.)

(B2) Organic compound / amorphous polyolefin (weight average molecular weight 3000, softening point 145 ° C.)
Paraffin wax (molecular weight 472, melting point 70 ° C.)
・ Microcrystalline wax (molecular weight 500-800, melting point 52 ° C.)
・ Stearic acid (molecular weight 284)
・ Dioctyl phthalate (DOP) (molecular weight 391)
・ Monostearic acid sorbitan ester (molecular weight 430)
-Bis (2-ethylhexyl) 4-cyclohexene-1,2-dicarboxylate (molecular weight 394)
1,2-cyclohexanedicarboxylic acid diisononyl ester (molecular weight 428)
・ Phenol antioxidant (1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane) (molecular weight 545, melting point 183 to 185 ° C.)

[Production of composition for three-dimensional printer]
The above (A), (B1) and (B2) were blended in the proportions shown in the table, and melt kneaded at 170 ° C. using a pressure kneader manufactured by Nippon Spindle Manufacturing Co., Ltd. (formerly Moriyama Seisakusho). . The obtained melt produced pellets having a diameter of 3 mm and a length of 3 mm using a pelletizer type plunger extruder manufactured by Toshin Co., Ltd.

[Evaluation of stringiness]
Using each manufactured pellet as a raw material, using an FDM type three-dimensional printer (CERA_P3 modeling range X150 mm × Y150 mm × Z150 mm, screw diameter φ20 mm, manufactured by S. Laboratories) equipped with an extrusion device having a pellet inlet, width Five laminated structures each having a square prism shape of 20 mm × depth 20 mm × height 20 mm and having a hollow center (width 10 mm, depth 10 mm) were manufactured. The molding temperature was 140 to 180 ° C., and the nozzle diameter was 1.0 mm. If the distance between each layered structure (modeled object) is 50 mm and one model is modeled and then stringing is observed when the nozzle is moved to the next modeled position, the thread tip from the edge of the modeled object The length up to was measured and used as the stringing length.
The case where the stringing length was less than 3 mm was evaluated as ◯, the case where it was 3 mm or more and less than 10 mm, and the case where it was 10 mm or more as x.

[Determination of degreasing and sintering]
Using each manufactured pellet as a raw material, using the same three-dimensional printer as above, at a molding temperature of 160 ° C. and a nozzle diameter of 1.0 mm, a rectangular column shape with a width of 20 mm, a depth of 20 mm, and a height of 20 mm is hollow inside. A laminated structure having a width of 10 mm and a depth of 10 mm was manufactured and used as a test piece.
The obtained test piece was placed on an alumina setter, and the degree of deformation (deformation, cracks, swelling) when zirconia and alumina were degreased to 500 ° C. at a heating rate of 15 ° C./h in the atmosphere was confirmed. Out of 5 test pieces each, it is rated as ◯ when 1 or less is deformed or cracked or deflated after degreasing, △ when 2 or 3 and × when 4 or more. did. After degreasing, the zirconia was heated up to 1350 ° C. and the alumina was heated up to 1600 ° C. at a heating rate of 50 ° C./h in the atmosphere, and sintered to obtain a sintered body.
Stainless steel was degreased by raising the temperature to about 500 ° C. at a temperature raising rate of 15 ° C./h in a nitrogen gas atmosphere, and deformation, cracks and blisters were confirmed in the same manner as described above. Thereafter, the temperature was raised to 1350 ° C. at a temperature raising rate of 50 ° C./h to obtain a sintered body.
The relative density of the sintered body was measured by Archimedes method.

Tables 1, 2 and 3 summarize the compositions and test results of the three-dimensional printer composition (pellet).

As shown in Tables 1 to 3, when the mass of the organic binder (B) is less than 7 when the mass of the inorganic powder (A) is 100, Comparative Example 1 and Comparative Example 5 are fluid. When the properties were poor and modeling was impossible and the number exceeded 30 (Comparative Example 2 and Comparative Example 6), the stringing property was high, and defects such as deformation were liable to occur during degreasing.
Moreover, when the mass ratio (B1) / (B2) with the thermoplastic resin of (B1) and the organic compound of (B2) is less than 0.2 (Comparative Example 4 and Comparative Example 8), When the defect became large and exceeded 1.4 (Comparative Example 3, Comparative Example 7 and Comparative Example 9), the stringiness increased.

  On the other hand, the mass of (B) is in the range of 7 to 30 and the mass (B1) / (B2) is in the range of 0.2 to 1.4 with respect to the mass 100 of (A). When pellets of Examples 1 to 5 (using zirconia powder as inorganic powder), Examples 6 to 10 (using alumina powder as inorganic powder) and Example 11 (using stainless steel powder as inorganic powder) are used, there is little stringiness A laminated structure having an excellent appearance could be produced, and a sintered body having high shape retention and high relative density (98% or more) could be obtained when the shaped body was degreased.

  According to the composition and method of the present invention, it becomes possible to efficiently produce a ceramic product having an excellent appearance using an FDM type three-dimensional printer.

Claims (6)

A composition for a three-dimensional printer containing (A) an inorganic powder and (B) an organic binder,
The organic binder (B) contains (B1) a thermoplastic resin having a weight average molecular weight of 10,000 or more, and (B2) an organic compound having a molecular weight or weight average molecular weight of 8000 or less,
The mass ratio of the inorganic powder (A) and the organic binder (B) is (A) / (B) = 100/7 to 100/30,
A composition for a three-dimensional printer, wherein a mass ratio of the thermoplastic resin (B1) and the organic compound (B2) is (B1) / (B2) = 0.2 to 1.4. 2. The composition for a three-dimensional printer according to claim 1, wherein the inorganic powder (A) is a metal oxide powder having an average particle diameter (D ₅₀ ) of 0.1 to 1.0 μm. 2. The composition for a three-dimensional printer according to claim 1, wherein the inorganic powder (A) is a metal powder having an average particle diameter (D ₅₀ ) of 3 to 10 μm.   The composition for a three-dimensional printer according to any one of claims 1 to 3, wherein the thermoplastic resin (B1) is a mixture of two or more kinds of thermoplastic resins.   The composition for a three-dimensional printer according to any one of claims 1 to 4, wherein at least one wax and at least one higher fatty acid are used as the organic compound (B2). A method of manufacturing a product made of ceramics, cermet, or metal,
Using the composition for a three-dimensional printer according to any one of claims 1 to 5, a step of forming a laminated structure by a hot melt lamination type three-dimensional printer, a step of degreasing the laminated structure, and A method comprising the step of sintering.