Filament, winding body, and method for manufacturing shaped object

Abstract

To provide a filament excellent in filament feeding property to a 3D printing device and melt-laminating property, and a wound body.SOLUTION: A filament according to the present disclosure is a filament for use in three dimensional modeling by fused deposition modeling, the filament including a semi-aromatic polyamide resin (a- 1) and a crystalline aliphatic polyamide resin (a- 2) in a total proportion of at least 70 mass% of the filament, the difference between the semi-crystallization time of the (A-1) semi-aromatic polyamide resin and the semi-crystallization time of the (a- 2) crystalline aliphatic polyamide resin is 1 to 500 seconds (wherein the semi-crystallization time is measured by depolarization photometry under the conditions of a sample melting temperature of the melting point of the polyamide resin + 30 °C, a sample melting time of 3 minutes, and a crystallization oil bath temperature of 140 °C). The mass ratio of (A-1) / (A-2) is 95 / 5 to 80 / 20, and the filament further contains (B) an inorganic crystal nucleating agent in a proportion of 0.1 to 10% by mass relative to the filament.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a filament, a wound body, and a method for manufacturing a shaped object, and more particularly to a filament containing a polyamide resin as a main component and used for three-dimensional modeling by fused deposition modeling. [Background technology]

[0002] A 3D printer is a type of rapid prototyping (3D modeling machine) that uses 3D data such as CAD and CG created on a computer as blueprints to produce three-dimensional objects made of plastic or other materials. 3D printers are classified by their layering method. Specifically, inkjet UV-curing 3D printers using acrylic photocurable resins (e.g., Objet Geometry's CONNEX and EDEN, and Keyence's AGILISTA-3000) are well-known. Fused deposition modeling 3D printers using thermoplastic resins such as acrylonitrile butadiene styrene (ABS), polycarbonate (PC), and polyphenylsulfone (PPSF) (e.g., Stratasys' FORTUS series, Dimension series, and uPrint series, and Solidoodle's Solidoodle 3) are also well-known. In addition, 3D printers using the SLS (Selective Laser Sintering) method, which sinters or melts resin-based powder materials or metal-based powder materials such as copper, bronze, titanium, and nickel by applying a high-power laser beam, or the SLM (Selective Laser Melting) method (e.g., the SLS series manufactured by 3D Systems, the RaFael550 manufactured by Aspect, and the EOS Int series manufactured by EOS) are also known.

[0003] 3D printers use resin (ink), which is the material used to create the object, to create shapes. For example, the resin (ink) used in fused deposition modeling is a thermoplastic resin filament that is melted and ejected from the 3D printer, and then layered onto the substrate to form the desired shape. With fused deposition modeling, the resin is ejected onto the substrate in a molten state, making it easy to create the desired shape.

[0004] Until now, in a wide range of fields, mainly in the manufacturing industry, such as architecture, medicine, education, and cutting-edge research, each part has been reduced to a size that can be printed using a 3D printer before the actual product is made, and it has been used for prototyping to verify the design and functionality, etc. However, in recent years, it has been expected to be used for more precise verification and for the production of actual resin molded products (Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2019 / 012886 Summary of the Invention [Problem to be solved by the invention]

[0006] Here, if a semi-aromatic polyamide resin is used as the resin used for the filament, it is expected that the resulting shaped object will have excellent strength. However, if the crystallization time of semi-aromatic polyamide resins, such as poly(metaxylylene adipamide), is slow, parts of the resin may shift or become loose during 3D printing. Additionally, the filament must be able to be properly wound onto the core material and properly fed into the 3D printer. The present invention aims to solve these problems by providing a filament and a winding body that have excellent filament supplyability and melt lamination properties to a 3D printing device. [Means for solving the problem]

[0007] In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by blending a crystalline aliphatic polyamide resin with a semi-aromatic polyamide resin, specifying the difference in the half-crystallization time between the two and the blend ratio of the two, and further adjusting the proportion of polyamide resin in the filament. Specifically, the above problems were solved by the following means. [1] A filament used for three-dimensional modeling by fused deposition modeling, (A-1) semi-aromatic polyamide resin and (A-2) crystalline aliphatic polyamide resin are contained in a total amount of 70% by mass or more of the filament, the difference between the half-crystallization time of the (A-1) semi-aromatic polyamide resin and the half-crystallization time of the (A-2) crystalline aliphatic polyamide resin is 1 to 500 seconds (wherein the half-crystallization time is measured by depolarized photometry under the conditions of a sample melting temperature of the polyamide resin melting point + 30°C, a sample melting time of 3 minutes, and a crystallization oil bath temperature of 140°C), the mass ratio of (A-1) / (A-2) is 95 / 5 to 80 / 20, The filament further contains (B) an inorganic crystal nucleating agent in a proportion of 0.1 to 10% by mass relative to the filament. [2] The filament according to [1], wherein the semi-aromatic polyamide resin (A-1) has a crystallization half time of 20 to 500 seconds, and the crystalline aliphatic polyamide resin (A-2) has a crystallization half time of 1 to 20 seconds. [3] The filament according to [1] or [2], further comprising (C) a fatty acid metal salt in an amount of 0.05 to 2 mass %. [4] The filament according to any one of [1] to [3], further comprising (D) carbon black in an amount of 0.05 to 5 mass %. [5] The filament according to any one of [1] to [4], further comprising (E) reinforcing fibers having a number average fiber length of 150 to 400 μm in a proportion of 1 to 20 mass %. [6] A filament according to any one of [1] to [5], wherein the (A-1) semi-aromatic polyamide resin contains diamine-derived structural units and dicarboxylic acid-derived structural units, and 70 mol % or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. [7] The semi-aromatic polyamide resin (A-1) has a crystallization half time (ST(P)) of 20 to 500 seconds, and the crystalline aliphatic polyamide resin (A-2) has a crystallization half time (ST(P)) of 1 to 20 seconds, Further, (C) a fatty acid metal salt is contained in an amount of 0.05 to 2 mass %, Further, (D) carbon black is contained in an amount of 0.05 to 5% by mass, Furthermore, (E) reinforcing fibers having a number average fiber length of 150 to 400 μm are contained in a proportion of 1 to 20 mass %, The filament according to any one of [1] to [6], wherein the (A-1) semi-aromatic polyamide resin contains diamine-derived structural units and dicarboxylic acid-derived structural units, and 70 mol % or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms. [8] A wound body having a core material and the filament according to any one of [1] to [7] wound around the core material. [9] A method for manufacturing a shaped object, comprising forming a three-dimensional structure using the filament according to any one of [1] to [7] by fused deposition modeling. [Effects of the Invention]

[0008] The present invention makes it possible to provide a filament and a winding body that have excellent filament supplyability to a 3D printing device and melt lamination properties. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a schematic diagram showing the state of forming a filament using a 3D printer. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as upper and lower limits. "A to B" means that the range is A or more and B or less. In addition, any combination of the upper and lower limit values ​​of the numerical values ​​in this specification is an example of this embodiment. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified.

[0011] In this specification, unless otherwise specified, the number average molecular weight is a value measured by the following method. The number average molecular weight (Mn) was measured by gel permeation chromatography (GPC) using a standard polymethyl methacrylate (PMMA) equivalent. Two columns packed with styrene polymer were used as the packing material, and the solvent was hexafluoroisopropanol (HFIP) with a sodium trifluoroacetate concentration of 2 mmol / L. The resin concentration was 0.02% by mass, the column temperature was 40°C, the flow rate was 0.3 mL / min, and measurements were performed using a refractive index detector (RI). A calibration curve was also measured by dissolving six levels of PMMA in HFIP.

[0012] In this specification, unless otherwise specified, the melting point (Tm) is a value measured by differential scanning calorimetry (DSC) in accordance with ISO 11357. A resin is placed in the measurement pan of a differential scanning calorimeter, heated to a temperature above the melting point at a rate of 10°C / min under a nitrogen atmosphere, and then rapidly cooled before measurement. The measurement conditions are a heating rate of 10°C / min, held at 350°C for 5 minutes, and then the melting point (Tm) is determined. The differential scanning calorimeter used is a "DSC-7020" manufactured by Hitachi High-Tech Science Corporation.

[0013] If the measurement methods, etc. described in the standards shown in this specification change from year to year, they will be based on the standards in effect as of January 1, 2024, unless otherwise specified. If the measurement methods, etc. described in the standards shown in this specification are abolished as of January 1, 2024, they will be based on the standards in effect at the time of abolition. The scale of Figure 1 may not be consistent with reality.

[0014] The filament of this embodiment is a filament used for three-dimensional modeling by fused deposition modeling, and is characterized in that it contains (A-1) semi-aromatic polyamide resin and (A-2) crystalline aliphatic polyamide resin in a total proportion of 70% by mass or more of the filament, the difference between the half-crystallization time of the (A-1) semi-aromatic polyamide resin and the half-crystallization time of the (A-2) crystalline aliphatic polyamide resin is 1 to 500 seconds (wherein the half-crystallization time is measured by depolarized spectroscopy under the conditions of a sample melting temperature of the polyamide resin + 30°C, a sample melting time of 3 minutes, and a crystallization oil bath temperature of 140°C), the mass ratio of (A-1) / (A-2) is 95 / 5 to 80 / 20, and further contains (B) an inorganic crystal nucleating agent in a proportion of 0.1 to 10% by mass of the filament. This configuration makes it possible to provide a filament that is excellent in filament supplyability to a 3D printing device and melt lamination properties. By using (A-1) semi-aromatic polyamide resin, the inherent properties of the semi-aromatic polyamide resin, such as mechanical strength, can be fully utilized in objects modeled using a 3D printer. However, many (A-1) semi-aromatic polyamide resins have a slow semi-crystallization time, which can be problematic when modeling using a 3D printer. The reason for this is explained below with reference to Figure 1. Figure 1 is a schematic diagram showing the state when filament is formed using a fused deposition modeling 3D printer, where 11 indicates the nozzle of the 3D printer, 12 indicates the filament immediately after ejection, 13 indicates the layered filament, 14 indicates the formed object, and 15 indicates the substrate. When forming a filament using a 3D printer, it is common to extrude the filament onto the surface of a substrate 15 as shown in Figure 1. However, when forming an object using a 3D printer, new filament 12 is extruded from the nozzle 11 before the crystallization of the layered filament 13 has progressed sufficiently, which can cause parts of the object 14 to shift or become loose during the 3D printing process. To solve this problem, in this embodiment, (A-2) a crystalline aliphatic polyamide resin with a relatively short half-crystallization time is blended, and (B) an inorganic crystal nucleating agent is blended. This composition shortens the time it takes for the filaments to crystallize, and effectively prevents the resulting shaped object from shifting or becoming loose. Furthermore, by making the total amount of polyamide resin in the filament 70% by mass or more, the filament becomes flexible, improving the filament's feedability to 3D printing devices and enabling it to be wound onto a winding body.

[0015] Hereinafter, the embodiments of the present invention will be described in detail. However, the explanation of the constituent elements described below is an example of an embodiment of the present invention, and the present invention is not limited to these contents.

[0016] The filament of this embodiment is a filament used for three-dimensional modeling by fused deposition modeling. Fused deposition modeling (FDM) is a three-dimensional modeling method in which filaments containing thermoplastic resin are melted at high temperature and stacked to create a three-dimensional object. For details about the fused deposition modeling, see, for example, Japanese Patent Application Laid-Open No. 2021-172084.

[0017] The filament of this embodiment contains (A-1) semi-aromatic polyamide resin and (A-2) crystalline aliphatic polyamide resin in a total amount of 70% by mass or more of the filament. Since the majority of the filament is polyamide resin, a flexible filament can be obtained. The total amount of the (A-1) semi-aromatic polyamide resin and the (A-2) crystalline aliphatic polyamide resin in the filament is preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 82% by mass or more, and is preferably 99% by mass or less, and may be 95% by mass or less or 90% by mass or less depending on the application, etc. The filament of this embodiment may contain only one kind of (A-1) semi-aromatic polyamide resin and (A-2) crystalline aliphatic polyamide resin, or may contain two or more kinds. When two or more kinds are contained, it is preferable that the total amount is within the above range.

[0018] The mass ratio of (A-1) / (A-2) in the filament of this embodiment is 95 / 5 to 80 / 20. With regard to the mass ratio of (A-1) / (A-2), when the total of (A-1) and (A-2) is 100 parts by mass, the content of (A-1) is preferably 82 parts by mass or more, more preferably 84 parts by mass or more, even more preferably 88 parts by mass or more, even more preferably 90 parts by mass or more, and even more preferably 91 parts by mass or more. By setting the mass ratio at or above the lower limit, production stability during filament production and withdrawal tends to be further improved. By setting the mass ratio at or below the upper limit, slippage and loosening between layers during filament melt lamination tends to be more effectively prevented.

[0019] Next, (A-1) semi-aromatic polyamide resin will be described. The semi-aromatic polyamide resin (A-1) used in this embodiment is a polyamide resin containing diamine-derived structural units and dicarboxylic acid-derived structural units, in which 20 to 80 mol % (preferably 30 to 80 mol %, more preferably 40 to 70 mol %) of the total structural units of the diamine-derived structural units and the dicarboxylic acid-derived structural units contain aromatic rings.

[0020] Examples of the (A-1) semi-aromatic polyamide resin include terephthalic acid-based polyamide resins (polyamide 6T, polyamide 9T, polyamide 10T) and xylylenediamine-based polyamide resins described below.

[0021] In this embodiment, the (A-1) semi-aromatic polyamide resin preferably contains diamine-derived structural units and dicarboxylic acid-derived structural units, and is a polyamide resin in which 70 mol % or more of the diamine-derived structural units are derived from xylylenediamine (hereinafter sometimes referred to as a "xylylenediamine-based polyamide resin").

[0022] The diamine-derived structural units of the xylylenediamine-based polyamide resin are more preferably 75 mol% or more, even more preferably 80 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, and particularly preferably 99 mol% or more, derived from xylylenediamine (preferably paraxylylenediamine and / or metaxylylenediamine).

[0023] The xylylenediamine is preferably paraxylylenediamine and / or metaxylylenediamine. The xylylenediamine preferably contains 0 to 100 mol% metaxylylenediamine and 100 to 0 mol% paraxylylenediamine (however, the total of metaxylylenediamine and paraxylylenediamine does not exceed 100 mol%), more preferably contains 10 to 100 mol% metaxylylenediamine and 90 to 0 mol% paraxylylenediamine, even more preferably contains 20 to 100 mol% metaxylylenediamine and 80 to 0 mol% paraxylylenediamine, still more preferably contains 40 to 100 mol% metaxylylenediamine and 60 to 0 mol% paraxylylenediamine, still more preferably contains 60 to 100 mol% metaxylylenediamine and 40 to 0 mol% paraxylylenediamine, and even more preferably contains 90 to 100 mol% metaxylylenediamine and 10 to 0 mol% paraxylylenediamine. In the xylylenediamine-based polyamide resin, the total of the constitutional units derived from paraxylylenediamine and the constitutional units derived from metaxylylenediamine preferably accounts for 80 mol % or more, more preferably 85 mol % or more, even more preferably 90 mol % or more, still more preferably 95 mol % or more, still more preferably 98 mol % or more, and still more preferably 99 mol % or more of the constitutional units derived from diamine. The upper limit of the total of the constitutional units derived from paraxylylenediamine and the constitutional units derived from metaxylylenediamine is 100 mol %.

[0024] Diamines other than metaxylylenediamine and paraxylylenediamine that can be used as raw diamine components for xylylenediamine-based polyamide resins include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine; 1,3-bis( Examples of the diamine include alicyclic diamines such as bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane; and diamines having an aromatic ring such as bis(4-aminophenyl)ether, paraphenylenediamine, and bis(aminomethyl)naphthalene. These diamines can be used alone or in combination of two or more.

[0025] On the other hand, the dicarboxylic acid-derived structural units of the xylylenediamine-based polyamide resin are preferably 70 mol% or more, more preferably 75 mol% or more, even more preferably 80 mol% or more, even more preferably 90 mol% or more, still more preferably 95 mol% or more, and particularly preferably 99 mol% or more, of which the structural units are derived from α,ω-linear aliphatic dicarboxylic acids preferably having 4 to 20 carbon atoms (preferably adipic acid).

[0026] Examples of α,ω-linear aliphatic dicarboxylic acids having 4 to 20 carbon atoms that are suitable for use as the raw dicarboxylic acid component of xylylenediamine-based polyamide resins include aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, undecanedioic acid, and 1,12-dodecanedioic acid. These can be used alone or in combination of two or more. Among these, at least one of adipic acid, sebacic acid, and 1,12-dodecanedioic acid is preferred, as this ensures that the melting point of the polyamide resin falls within a range suitable for molding and processing. Adipic acid and / or sebacic acid is more preferred, and adipic acid is even more preferred.

[0027] Examples of dicarboxylic acid components other than those mentioned above include phthalic acid compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid, and isomers of naphthalenedicarboxylic acid such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and these can be used alone or in combination of two or more.

[0028] The (A-1) semi-aromatic polyamide resin used in this embodiment is preferably a xylylenediamine-based polyamide resin that contains diamine-derived structural units and dicarboxylic acid-derived structural units, in which 70 mol % or more of the diamine-derived structural units are derived from xylylenediamine and 70 mol % or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

[0029] Although the xylylenediamine-based polyamide resin is primarily composed of diamine-derived structural units and dicarboxylic acid-derived structural units, other structural units are not completely excluded, and it goes without saying that it may contain structural units derived from lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid. Here, "major component" refers to the structural units constituting the xylylenediamine-based polyamide resin in which the total number of diamine-derived structural units and dicarboxylic acid-derived structural units is the largest among all structural units. In this embodiment, the total of the diamine-derived structural units and dicarboxylic acid-derived structural units in the xylylenediamine-based polyamide resin preferably accounts for 90% by mass or more of all structural units, more preferably 95% by mass or more, even more preferably 97% by mass or more, and even more preferably 99% by mass or more.

[0030] It is also preferable to use a polyamide resin produced using biomass raw materials (biomass polyamide resin) as the xylylenediamine-based polyamide resin, which can reduce the environmental impact. Bio-adipic acid can be used as a biomass raw material for xylylenediamine-based polyamide resins. Mass-balance certified (ISCC PLUS) adipic acid can also be used. Mass-balance certification means that the amount of renewable or bio-based raw materials used at each factory or production facility, and the amount of products produced or shipped are quantified, along with the quality, and guaranteed.

[0031] The (A-1) semi-aromatic polyamide resin may be a recycled (A-1) semi-aromatic polyamide resin product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or scraps generated when molding a molded product from a resin composition, pellets, or filaments.

[0032] The crystallization half time of the semi-aromatic polyamide resin (A-1) is preferably 20 to 500 seconds. By setting the crystallization half time to be equal to or greater than the lower limit, production stability during filament production and take-up tends to be further improved. Furthermore, by setting the crystallization half time to be equal to or less than the upper limit, slippage and loosening between layers during filament melt lamination tends to be effectively prevented. The crystallization half time of the semi-aromatic polyamide resin (A-1) is preferably 30 seconds or more, more preferably 50 seconds or more, and even more preferably 70 seconds or more, and may be 80 seconds or more or 90 seconds or more, and may be 400 seconds or less, more preferably 300 seconds or less, and even more preferably 200 seconds or less, and may be 150 seconds or less or 120 seconds or less. When the filament of this embodiment contains two or more types of (A-1) semi-aromatic polyamide resins, the crystallization half time is the measurement result of a sample obtained by melt-kneading only the (A-1) semi-aromatic polyamide resins in that ratio. The same applies to the (A-2) aliphatic polyamide resin.

[0033] The melting point of the (A-1) semi-aromatic polyamide resin is preferably 150°C or higher, more preferably 180°C or higher, and even more preferably 200°C or higher, and is preferably 350°C or lower, more preferably 330°C or lower, and even more preferably 300°C, and may even be 280°C or lower, or 250°C or lower. When two or more types of (A-1) semi-aromatic polyamide resins are contained, the melting point thereof is the result of measurement of a sample obtained by melt-kneading only the (A-1) semi-aromatic polyamide resins in that ratio. The same applies to the (A-2) aliphatic polyamide resin.

[0034] The lower limit of the number average molecular weight (Mn) of the (A-1) semi-aromatic polyamide resin is preferably 6,000 or more, more preferably 8,000 or more, and even more preferably 10,000 or more, and is preferably 100,000 or less, more preferably 50,000 or less. Within such ranges, the heat resistance is improved. When two or more types of (A-1) semi-aromatic polyamide resins are contained, the number average molecular weight thereof is the number average molecular weight of the mixture. The same applies to (A-2) aliphatic polyamide resins.

[0035] Next, (A-2) the crystalline aliphatic polyamide resin will be described. Examples of (A-2) aliphatic polyamide resins include polyamide 4, polyamide 46, polyamide 6, polyamide 66, polyamide 666, polyamide 610, polyamide 11, and polyamide 12, with polyamide 6, polyamide 66, and polyamide 666 being preferred, and polyamide 66 being more preferred. Furthermore, polyamides such as the above-mentioned polyamide 66 are also intended to include those modified with other monomer units (diamines, dicarboxylic acids, lactams, aliphatic aminocarboxylic acids, etc.) at a ratio of 10% by mass or less (preferably less than 5% by mass, more preferably less than 3% by mass, and even more preferably less than 1% by mass) of the constituent units of the polyamide.

[0036] It is also preferable to use a polyamide resin (biomass polyamide resin) produced from biomass raw materials as the (A-2) crystalline aliphatic polyamide resin. By using a biomass polyamide resin, it is possible to reduce the environmental load. The (A-2) crystalline aliphatic polyamide resin may be a recycled (A-2) crystalline aliphatic polyamide resin product (including recovered products, material recycled products, chemical recycled products, etc.), a rejected product, or scraps generated when molding a molded product from a resin composition, pellets, or filaments.

[0037] The crystallization half time of the (A-2) aliphatic polyamide resin is preferably 1 to 20 seconds. By setting it to be equal to or greater than the lower limit, it tends to be possible to more effectively prevent slippage and loosening between layers during filament melt lamination. Furthermore, by setting it to be equal to or less than the upper limit, it tends to be possible to further improve production stability during filament production and take-up. The crystallization half time of the (A-2) crystalline aliphatic polyamide resin is preferably 1.5 seconds or more, more preferably 2 seconds or more, and even more preferably 2.5 seconds or more, and is preferably 15 seconds or less, more preferably 10 seconds or less, and even more preferably 5 seconds or less.

[0038] The melting point of the (A-2) aliphatic polyamide resin is preferably 150°C or higher, more preferably 180°C or higher, even more preferably 200°C or higher, and may be 230°C or higher or 250°C or higher, and is preferably 350°C or lower, more preferably 330°C or lower, even more preferably 300°C, and may be 280°C or lower.

[0039] The lower limit of the number average molecular weight (Mn) of the (A-2) aliphatic polyamide resin is preferably 6,000 or more, more preferably 8,000 or more, and even more preferably 10,000 or more, and is preferably 100,000 or less, more preferably 50,000 or less. Within such ranges, the heat resistance is improved.

[0040] In the filament of this embodiment, the difference between the half-crystallization time of the (A-1) semi-aromatic polyamide resin and the half-crystallization time of the (A-2) crystalline aliphatic polyamide resin is 1 to 500 seconds. By making the difference equal to or greater than the lower limit, production stability during filament production and take-up tends to be further improved. Furthermore, by making the difference equal to or less than the upper limit, slippage and loosening between layers during filament melt lamination tends to be more effectively prevented. The difference in half-crystallization time is preferably 10 seconds or more, more preferably 20 seconds or more, and even more preferably 50 seconds or more, and is preferably 40 seconds or less, more preferably 300 seconds or less, and even more preferably 200 seconds or less. Here, the crystallization half time refers to the time measured by depolarized photometry under the conditions of a sample melting temperature of the polyamide resin melting point + 30°C, a sample melting time of 3 minutes, and a crystallization oil bath temperature of 140°C.

[0041] The filament of this embodiment may or may not contain a polyamide resin other than the (A-1) semi-aromatic polyamide resin and the (A-2) crystalline aliphatic polyamide resin. The content of the polyamide resin other than the (A-1) semi-aromatic polyamide resin and the (A-2) crystalline aliphatic polyamide resin in the filament of this embodiment is preferably 0% by mass or more and less than 10% by mass, more preferably 0% by mass or more and less than 5% by mass, even more preferably 0% by mass or more and less than 3% by mass, and even more preferably 0% by mass or more and less than 1% by mass. The filament of this embodiment may contain only one or two or more polyamide resins other than the (A-1) semi-aromatic polyamide resin and the (A-2) crystalline aliphatic polyamide resin. When two or more types are contained, the total amount is preferably within the above range.

[0042] The filament of this embodiment may or may not contain a thermoplastic resin other than polyamide resin. Specific examples include polyacetal resin, polyester resin, polyolefin resin, polycarbonate resin, etc. The content of the thermoplastic resin other than polyamide resin in the filament of this embodiment is preferably 0% by mass or more and less than 5% by mass, more preferably 0% by mass or more and less than 3% by mass, even more preferably 0% by mass or more and less than 1% by mass, and even more preferably 0% by mass or more and less than 0.1% by mass. The filament of the present embodiment may contain only one type of thermoplastic resin other than polyamide resin, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0043] The filament of this embodiment contains (B) an inorganic crystal nucleating agent in a proportion of 0.1 to 10 mass % of the filament. By including (B) an inorganic crystal nucleating agent, the solidification of the filament, which is the product ejected by 3D printing, can be accelerated, and loosening and sagging of the resulting model can be effectively suppressed. (B) The inorganic crystal nucleating agent is not particularly limited as long as it is an inorganic compound that remains unmelted during melt processing and can become the nucleus of a crystal during the cooling process. Examples of (B) inorganic crystal nucleating agents include graphite, molybdenum disulfide, barium sulfate, talc, calcium carbonate, sodium phosphate, mica, and kaolin, and at least one selected from talc and calcium carbonate is more preferred, with talc being even more preferred. The lower limit of the number average particle size of the (B) inorganic crystal nucleating agent is preferably 0.1 μm or more, more preferably 1 μm or more, even more preferably 5 μm or more, and even more preferably 10 μm or more, and is preferably 40 μm or less, more preferably 30 μm or less, even more preferably 28 μm or less, even more preferably 25 μm or less, and even more preferably 20 μm or less. By setting the number average particle size to 40 μm or less, the number of (B) inorganic crystal nucleating agent that becomes nuclei increases compared to the amount of (B) inorganic crystal nucleating agent blended, and the crystal structure tends to be more stable.

[0044] The content of the inorganic nucleating agent (B) in the filament of this embodiment is 0.1% by mass or more, preferably 0.5% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more, and even more preferably 0.8% by mass or more. By making it equal to or greater than the lower limit, the crystalline state in the filament can be more sufficiently stabilized. Furthermore, the content of the inorganic nucleating agent (B) in the filament of this embodiment is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, and may be 2% by mass or less. When the filament of this embodiment contains (B) an inorganic nucleating agent, it may contain only one type of (B) inorganic nucleating agent, or may contain two or more types. When two or more types are contained, it is preferable that the total amount is in the above range.

[0045] The filament of this embodiment preferably further contains (C) a fatty acid metal salt in a proportion of 0.05 to 2 mass %. By containing (C) a fatty acid metal salt, the processability of the filament or shaped article tends to be further improved. The fatty acid constituting the (C) fatty acid metal salt is preferably a fatty acid having a carbon chain length of 20 or more, more preferably a fatty acid having a carbon chain length of 20 to 35, and even more preferably a fatty acid having a carbon chain length of 25 to 30. Specific examples of the fatty acid constituting the fatty acid metal salt include stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, and ricinoleic acid, with stearic acid being preferred. Examples of metals constituting the (C) fatty acid metal salt include calcium, magnesium, zinc, aluminum, barium, and lithium, with barium being preferred.

[0046] When the filament of this embodiment contains (C) a fatty acid metal salt, the content thereof is typically 0.05% by mass or more, preferably 0.1% by mass or more, relative to 100% by mass of the filament, and typically 2% by mass or less, preferably 1.5% by mass or less, more preferably 1.0% by mass or less, even more preferably 0.5% by mass or less, and even more preferably 0.3% by mass or less. The filament of this embodiment may contain only one type of (C) fatty acid metal salt, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0047] The filament of this embodiment preferably further contains (D) carbon black in an amount of 0.05 to 5 mass %. By containing (D) carbon black, it is possible to impart design properties to the resulting shaped article. (D) Carbon black is not limited in type, raw material, or production method, and any of furnace black, channel black, acetylene black, ketjen black, etc. can be used. Of these, furnace black is preferred.

[0048] (D) DBP oil absorption of carbon black (unit: cm 3 / 100g) is 40~300cm 3 The upper limit is preferably 300 cm / 100 g. 3 / 100g or less is preferable, and 200cm 3More preferably, the lower limit is 40 cm / 100 g or less. 3 / 100g or more is preferable, 80cm 3 / 100g or more is more preferable, 100cm 3 / 100g or more is more preferable, 120cm 3 By adjusting the DBP oil absorption amount (unit: cm) to within the above upper and lower limits, the appearance of the resulting molded article tends to be improved. 3 / 100g) can be measured in accordance with JIS K6217-4.

[0049] (D) Nitrogen adsorption specific surface area of ​​carbon black (unit: m 2 / g) is 100 to 200m 2 The nitrogen adsorption specific surface area is measured in accordance with JIS K6217-2.

[0050] The number-average particle size (unit: nm) of (D) carbon black is preferably 5 to 60 nm. The upper limit is preferably 60 nm or less, more preferably 40 nm or less, even more preferably 30 nm or less, and even more preferably 25 nm or less. The lower limit is preferably 10 nm or more, more preferably 13 nm or more, even more preferably 16 nm or more, and even more preferably 19 nm or more. By keeping the size within the above upper and lower limits, the appearance of the resulting molded article tends to be improved. The number-average particle size can be determined by obtaining a magnified image of an aggregate according to the procedure described in ASTM D3849 ((D) Standard Test Method for Carbon Black - Morphological Characterization by Electron Microscopy), measuring the particle sizes of 3,000 unit constituent particles from this aggregate image, and then arithmetically averaging the measured particle sizes.

[0051] (D) Carbon black is preferably blended as a masterbatch in advance with a thermoplastic resin, since this increases the degree of dispersion of (D) Carbon black and tends to improve the design properties of the resulting shaped object.

[0052] When the filament of this embodiment contains (D) carbon black, the content thereof is typically 0.05% by mass or more, preferably 0.10% by mass or more, and more preferably 0.15% by mass or more, relative to 100% by mass of the filament, and is typically 5% by mass or less, preferably 3% by mass or less, more preferably 2% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.5% by mass or less. The filament of this embodiment may contain only one type of (D) carbon black, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0053] The filament of this embodiment preferably further contains (E) reinforcing fibers having a number average fiber length of 150 to 400 μm in a proportion of 1 to 20 mass %. By including (E) reinforcing fibers, a shaped article having excellent mechanical strength can be obtained. The (E) reinforcing fibers may be organic reinforcing fibers or inorganic reinforcing fibers, with inorganic reinforcing fibers being preferred. (E) The reinforcing fibers are preferably plant fibers, carbon fibers, glass fibers, alumina fibers, boron fibers, ceramic fibers, aramid fibers, etc., more preferably selected from carbon fibers and glass fibers, and even more preferably glass fibers.

[0054] The glass fiber may be a fiber obtained by melt spinning a commonly supplied glass such as E-glass, C-glass, A-glass, S-glass, D-glass, R-glass, or alkali-resistant glass, but any glass fiber that can be made into a glass fiber may be used, and is not particularly limited. In the present invention, it is preferable to include E-glass.

[0055] The glass fiber is preferably surface-treated with a surface treatment agent such as a silane coupling agent, for example, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-aminopropyltriethoxysilane. The amount of the surface treatment agent attached is preferably 0.01 to 1.0 mass% of the glass fiber. If necessary, the glass fiber may be surface-treated with a lubricant such as a fatty acid amide compound or silicone oil, an antistatic agent such as a quaternary ammonium salt, a resin capable of forming a film, such as an epoxy resin or urethane resin, or a mixture of a resin capable of forming a film with a heat stabilizer or a flame retardant.

[0056] The glass fiber used for the filament of this embodiment is commercially available, such as T275H, T286H, T756H, T289, T289DE, T289H, and T296GH manufactured by Nippon Electric Glass (NEG), DEFT2A manufactured by Owens Corning, HP3540 manufactured by PPG, CSG3PA-810S and CSG3PA-820 manufactured by Nitto Boseki Co., Ltd., EFH50-31 manufactured by Central Glass Fiber, and CS301HP manufactured by Chongqing Polycomp International (all trade names).

[0057] On the other hand, the carbon fiber used for the filament is preferably a PAN-based carbon fiber.

[0058] (E) The cross section of the reinforcing fiber may be either circular or non-circular (e.g., elliptical, oval, rectangular, rectangular with semicircular sides joined to both short sides, cocoon-shaped, etc.), and is preferably circular. When a reinforcing fiber having a circular cross section is used in the present invention, the effects of improving flame retardancy and mechanical strength are particularly significant. The circular shape here includes not only a perfect circle in the geometrical sense, but also what is normally called a circle in the technical field of the present invention. Examples of reinforcing fibers with a non-circular cross section include the flat reinforcing fibers described in paragraphs 0048 to 0052 of JP 2012-214819 A, the contents of which are incorporated herein by reference.

[0059] The number average fiber length of the (E) reinforcing fibers in the filament of this embodiment is 150 μm or more, preferably 180 μm or more, more preferably 210 μm or more, and even more preferably 220 μm or more. The upper limit is preferably 400 μm or less, preferably 370 μm or less, more preferably 340 μm or less, and even more preferably 330 μm or less. Usually, chopped strands or other fibers with a number average fiber length of about several mm are blended and melt-kneaded to form filaments, so the number average fiber length of the (E) reinforcing fibers in the filaments is about 150 to 400 μm.

[0060] The number average fiber diameter of the (E) reinforcing fibers used in the filament of this embodiment is preferably 1 μm or more, more preferably 2 μm or more, and even more preferably 5 μm or more, and the upper limit is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less.

[0061] When the filament of this embodiment contains (E) reinforcing fiber, its content is typically 1% by mass or more, preferably 3% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, and may be 10% by mass or more, and is typically 20% by mass or less, preferably 18% by mass or less. By setting the content at or above the lower limit, the mechanical strength of the resulting shaped object can be improved, and flame retardancy can also be improved. On the other hand, by setting the amount of (E) reinforcing fiber to the upper limit or less, the filament can be made easy to take up during filament production and easy to feed during melt lamination. The filament of this embodiment may contain only one type of (E) reinforcing fiber, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0062] The filament of this embodiment may contain components other than the above (A) to (E). Examples of components other than those mentioned above include stabilizers, flame retardants, flame retardant assistants, alkalis, elastomers, titanium oxide, hydrolysis resistance improvers, matting agents, plasticizers, dispersants, antistatic agents, coloring inhibitors, antigelling agents, colorants, etc. For details of these, please refer to paragraphs 0130 to 0155 of Japanese Patent No. 4894982 and paragraphs 0047 to 0103 of International Publication No. 2021 / 241471, the contents of which are incorporated herein by reference. The content of components other than the above (A) to (E) is preferably 0 to 20% by mass, more preferably 0 to 10% by mass, even more preferably 0 to 5% by mass, and even more preferably 0 to 3% by mass, and may be 0 to 1% by mass.

[0063] The wound body of this embodiment has a core material and the filament of this embodiment wound around the core material. The filament of this embodiment has a high content of (A) polyamide resin of 70% by mass or more, so that the filament is flexible and has excellent windability. The filament in this embodiment may be a monofilament or a multifilament, and is preferably a monofilament. The filaments of this embodiment may be drawn filaments or undrawn filaments, and are preferably undrawn filaments.

[0064] The filament of this embodiment preferably has a diameter of 0.2 to 5.0 mm, more preferably 1.5 to 3.2 mm, and even more preferably 1.6 to 3.1 mm. The diameter of the filament is the average of the maximum major axis and the minimum minor axis in a cross section of the filament cut perpendicular to the longitudinal direction.

[0065] Next, a shaped object obtained from the filament of this embodiment will be described. The shaped object of this embodiment is preferably produced by three-dimensional modeling using a fused deposition modeling method. That is, in this embodiment, a method for manufacturing a shaped object is disclosed, which includes forming a three-dimensional structure from a filament by fused deposition modeling.

[0066] The uses of the filament of this embodiment for objects manufactured using a 3D printer are not particularly limited, but they are widely used for automobile and other transportation vehicle parts, general machine parts, precision machine parts, electronic and electrical equipment parts, office automation equipment parts, building materials and housing-related parts, medical devices, leisure and sporting goods, play equipment, medical supplies, everyday items such as food packaging films, defense and aerospace products, etc. They are also preferably used for manufacturing prototypes of these products. [Example]

[0067] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0068] 1. Raw materials [Table 1]

[0069] <Measurement of half-crystallization time> The semi-crystallization time of polyamide resin was measured by depolarized photometry under the following conditions: sample melting temperature: melting point of polyamide resin + 30°C, sample melting time: 3 minutes, crystallization oil bath temperature: 140°C. The unit is shown in seconds.

[0070] 2. Examples 1 to 3 and Comparative Examples 1 to 3 <Compound> As shown in Table 1, each component was weighed (each component is in mass%), and the components other than the glass fiber and carbon fiber were blended in a tumbler. The blend was then fed into the base of a twin-screw extruder (Shibaura Machine Co., Ltd., TEM26SS) and melted. The reinforcing fibers were then side-fed to produce polyamide resin pellets. The temperature of the twin-screw extruder was set to 280°C.

[0071] <Filament manufacturing> The resin composition obtained above was melt-extruded in a single-screw extruder (Filabot, EX6) with a 6 mm diameter screw, extruded into strands through a single-hole die with a diameter of 1.75 mm, and stretched while being wound on a roll. The filament was wound around a core material to obtain a wound body. The temperature of the single-screw extruder was set at 265°C.

[0072] <Filament modeling> The filament was pulled from the wound body obtained above and set into the nozzle of a 3D printing device (INTAMSYS, FUNMATHT). The nozzle temperature was set to 240°C, the stage temperature to 90°C, and the building chamber temperature to 28°C. The filament resin was heated and melted in the manifold before the nozzle and extruded from the Φ0.4mm nozzle opening and continuously melted and laminated to form a 100mm x 15mm x 4mm rectangular test piece-shaped laminate. The printing direction was the planar longitudinal direction of the rectangular test piece, and once the printing of one flat layer was completed, the next layer was continuously printed.

[0073] <<Filament retractability>> The stability of the filaments extruded from the die of the single-screw extruder when wound onto a core material was evaluated. A: It was possible to wind the wire onto the core material stably at a uniform speed without any pulsation. B: Other than A above, for example, pulsation occurred during take-up, causing the filament to bend when wound onto the core material.

[0074] <<Filament supply to 3D printing equipment>> The stability of continuously supplying filament from a reel to the nozzle of a 3D printing device was evaluated. A: We were able to complete the modeling fully automatically without any human support. B: Other than A above, for example, the filament bent significantly during the process, and occasionally a person had to support it.

[0075] <<Melt lamination>> We evaluated the process of melt-layering a model using a 3D printing device. A: No deformation of the object occurred during fusion lamination. B: Slippage and loosening occurred between layers during melt lamination.

[0076] <<Bending properties of test specimen>> Using the laminate strip test pieces of 100 mm × 15 mm × 4 mm obtained above, the bending strength (unit: MPa) and bending modulus (unit: GPa) were measured in an environment of a temperature of 23°C and a humidity of 50% in accordance with ISO178.

[0077] <<Water absorption characteristics>> The laminated strip test piece obtained above, measuring 100 mm x 15 mm x 4 mm, was immersed in water at 23°C for 24 hours, and the mass change rate was measured. Mass change rate (unit: %) = [(mass of laminate after immersion - mass of laminate before immersion) / (mass of laminate before immersion)] x 100 [Table 2]

[0078] In Example 2, an attempt was made to produce a filament with a glass fiber content of 30 mass %, but it was difficult to produce the filament.

[0079] Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to those skilled in the art that various modifications can be made without departing from the spirit and scope of the invention. [Explanation of symbols]

[0080] 11 3D printer nozzle 12 Filament immediately after ejection 13 Stacked Filaments 14 Sculptures 15 Base material

Claims

1. A filament used in three-dimensional modeling by fused deposition modeling, (A-1) semi-aromatic polyamide resin and (A-2) crystalline aliphatic polyamide resin are contained in a total amount of 70% by mass or more of the filament, the difference between the half-crystallization time of the (A-1) semi-aromatic polyamide resin and the half-crystallization time of the (A-2) crystalline aliphatic polyamide resin is 1 to 500 seconds (wherein the half-crystallization time is measured by depolarized photometry under the conditions of a sample melting temperature of the polyamide resin melting point + 30°C, a sample melting time of 3 minutes, and a crystallization oil bath temperature of 140°C), the mass ratio of (A-1) / (A-2) is 95 / 5 to 80 / 20; The filament further contains (B) an inorganic crystal nucleating agent in a proportion of 0.1 to 10% by mass relative to the filament.

2. The filament according to claim 1, wherein the semi-aromatic polyamide resin (A-1) has a crystallization half time of 20 to 500 seconds, and the crystalline aliphatic polyamide resin (A-2) has a crystallization half time of 1 to 20 seconds.

3. The filament according to claim 1 or 2, further comprising (C) a fatty acid metal salt in an amount of 0.05 to 2 mass %.

4. The filament according to claim 1 or 2, further comprising (D) carbon black in an amount of 0.05 to 5 mass %.

5. The filament according to claim 1 or 2, further comprising (E) reinforcing fibers having a number average fiber length of 150 to 400 μm in a proportion of 1 to 20 mass %.

6. The filament according to claim 1 or 2, wherein the (A-1) semi-aromatic polyamide resin contains diamine-derived structural units and dicarboxylic acid-derived structural units, and 70 mol% or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol% or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

7. the semi-aromatic polyamide resin (A-1) has a crystallization half time (ST(P)) of 20 to 500 seconds, and the crystalline aliphatic polyamide resin (A-2) has a crystallization half time (ST(P)) of 1 to 20 seconds; Further, (C) a fatty acid metal salt is contained in an amount of 0.05 to 2% by mass, Further, (D) carbon black is contained in an amount of 0.05 to 5% by mass, Furthermore, (E) reinforcing fibers having a number average fiber length of 150 to 400 μm are contained in a proportion of 1 to 20 mass%, The filament according to claim 1, wherein the (A-1) semi-aromatic polyamide resin contains diamine-derived structural units and dicarboxylic acid-derived structural units, and 70 mol% or more of the diamine-derived structural units are derived from xylylenediamine, and 70 mol% or more of the dicarboxylic acid-derived structural units are derived from an α,ω-linear aliphatic dicarboxylic acid having 4 to 20 carbon atoms.

8. A winding body comprising a core material and the filament according to claim 1, 2 or 7 wound around the core material.

9. A method for manufacturing a shaped object, comprising forming a three-dimensional structure using the filament according to claim 1, 2 or 7 by fused deposition modeling.

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