Thermoplastic resin filament for 3D printer, object made using the same, and manufacturing method thereof

Abstract

To provide a thermoplastic resin filament that has stable mechanical properties and can be used to create objects continuously for long periods of time without clogging a nozzle, regardless of a nozzle diameter of the 3D printer, a molding speed, or other molding conditions.SOLUTION: In a thermoplastic resin filament for a 3D printer, comprising a thermoplastic resin containing an amorphous resin (a), a filament diameter is 1.500 to 3.000 mm, and a process capability (diameter) calculated from an average value and standard deviation of the filament diameter satisfies the following formula (1): Process capability (diameter)=(average diameter × 0.04) / (6 × standard deviation)≥1.33 ... (1), the process capability (roundness) calculated from the average value and standard deviation of the roundness of the filament (long diameter) / (short diameter) satisfies the following formula (2): Process capability (roundness)=(1.03 - average roundness) / (3 × standard deviation)≥1.33 ... (2).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a thermoplastic resin filament for a 3D printer, a shaped article thereof, and a method for manufacturing the same.

Background Art

[0002] Additive manufacturing techniques represented by 3D printers do not use molds, which are essential in conventional injection molding, and thus have the advantage of being able to produce prototypes in a short period of time. For example, they are often used for prototyping parts for function verification. On the other hand, in recent years, the need for applying these techniques to the direct manufacturing of small-lot, multi-variety products, as one of the techniques for producing shaped articles with complex structures, has also been increasing. Among such backgrounds, the fused deposition modeling method, which is widely used in many 3D printers, is a technique in which a filamentous resin material is supplied to a 3D printer nozzle, the resin material is melted at the nozzle, and the extruded resin is laminated by pressing it against a modeling table.

[0003] As a raw material used for filaments for 3D printers, thermoplastic resins such as polylactic acid have generally been preferably used from the viewpoints of processability and fluidity (see Patent Document 1). In Patent Document 2 below, it is reported that a filament for a 3D printer has a high roundness and little variation in wire diameter, which reduces the discharge unevenness during 3D printer modeling and results in a good appearance of the obtained shaped article. Also, in Patent Document 3 below, a method of passing a filament extruded from an extruder through a sizing device while vacuum-sucking the filament has been reported as a method for obtaining a filament having a stable wire diameter and a cross-sectional shape close to a perfect circle. In Patent Documents 4 and 5 below, in order to obtain a shaped article having excellent mechanical properties such as heat resistance and tensile strength, the use of super engineering plastics in the raw material and filaments using fiber-reinforced thermoplastic resins have been reported.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0005] The hot-melt lamination method is currently a method that can use thermoplastic resins used in industrial parts, so industrial utilization has attracted particular attention, and stability of physical properties and manufacturing cycles is required. However, in the conventionally reported methods, especially when using amorphous resins, the filament diameter and roundness are not sufficiently stable, and variations occur in the mechanical properties of the molded products by changing molding conditions such as the nozzle diameter and molding speed of the 3D printer, or there is a problem that clogging occurs in the nozzle when molding continuously for a long time.

[0006] Therefore, in order to solve the above problems, an object of the present invention is to provide a thermoplastic resin filament that can stably form a molded product continuously for a long time without clogging in the nozzle, regardless of molding conditions such as the nozzle diameter and molding speed of a 3D printer, and a molded product thereof, and a manufacturing method thereof.

Means for Solving the Problems

[0007] The configurations of the thermoplastic resin filament, the molded product thereof, and the manufacturing method thereof according to the present invention for solving the above problems are as follows.

[0008] [1] A thermoplastic resin filament for a 3D printer made of a thermoplastic resin containing an amorphous resin (a), the filament has a wire diameter of 1.500 to 3.000 mm, the process capability (wire diameter) calculated by the average value of the wire diameter of the filament and the standard deviation satisfies the following formula (1): Process capability (wire diameter) = (average wire diameter × 0.04) / (6 × standard deviation) ≥ 1.33 ··· (1) and the process capability (circularity) calculated by the average value and the standard deviation of the circularity = (major axis) / (minor axis) of the filament satisfies the following formula (2): Process capability (circularity) = (1.03 - average circularity) / (3 × standard deviation) ≥ 1.33 ··· (2) A thermoplastic resin filament for a 3D printer that satisfies the above.

[0009] [2] The thermoplastic resin filament for a 3D printer according to [1], wherein the calculation of each process capability of the formula (1) and the formula (2) is calculated using 5,000 or more measurement values.

[0010] [3] The thermoplastic resin filament for a 3D printer according to [1] or [2], wherein the amorphous resin (a) contains a polyphenylene ether resin.

[0011] [4] Further, the thermoplastic resin contains a crystalline resin (b), and the crystalline resin (b) contains a polyamide resin. The thermoplastic resin filament for a 3D printer according to [3].

[0012] [5] The thermoplastic resin filament for a 3D printer according to [3], wherein the amorphous resin (a) further contains a styrene resin.

[0013] [6] A shaped article using the thermoplastic resin filament for a 3D printer according to any one of [1] to [5].

[0014] [7] A method for manufacturing a thermoplastic resin filament for a 3D printer according to any one of [1] to [5], injecting the molten thermoplastic resin from a single-orifice die to obtain a filament, and after injection, slowly cooling the filament at a rate of 15°C / second or less to a temperature below the glass transition temperature (Tg). A method for manufacturing a thermoplastic resin filament for a 3D printer, comprising the above steps.

Effect of the Invention

[0015] According to the present invention, due to the stable wire diameter and roundness, the mechanical properties are stable, and a thermoplastic resin filament capable of continuously forming shaped articles for a long time can be obtained. In addition, a shaped article with excellent impact strength and little variation in impact strength can be obtained. Further, a method for manufacturing a thermoplastic resin filament capable of continuously forming shaped articles for a long time with stable mechanical properties can be provided.

Brief Description of the Drawings

[0016]

Figure 1

Embodiments for Carrying Out the Invention

[0017] Hereinafter, a thermoplastic resin filament for a 3D printer according to the present invention, its shaped article, and its manufacturing method will be described together with their embodiments.

[0018] <Thermoplastic Resin Filament for 3D Printer> The thermoplastic resin filament for a 3D printer of the present embodiment is a thermoplastic resin filament for a 3D printer comprising an amorphous resin (a), the wire diameter of the filament is 1.500 to 3.000 mm, the process capability (wire diameter) calculated by the average value of the wire diameter of the filament and the standard deviation is represented by the following formula (1): Process capability (wire diameter) = (wire diameter average value × 0.04) / (6 × standard deviation) ≧ 1.33 ··· (1) satisfies The roundness of the filament = the process capability (roundness) calculated by the average value and standard deviation of (major axis) / (minor axis) satisfies the following formula (2): Process capability (roundness) = (1.03 - average roundness value) / (3 × standard deviation) ≧ 1.33 ··· (2) characterized by satisfying The above filament is linear and has stable roundness. By using a filament with stable wire diameter and roundness, the mechanical properties are stable, and it becomes a filament capable of continuously forming a shaped object for a long time. Furthermore, a shaped product with excellent impact strength and little variation in impact strength can be obtained.

[0019] The thermoplastic resin filament for a 3D printer according to the present invention is made of a thermoplastic resin containing at least an amorphous resin (a), but may contain other resins according to the purpose. For example, the thermoplastic resin may contain a crystalline resin (b) in addition to the amorphous resin (a). For example, the thermoplastic resin may be an alloy of the amorphous resin (a) and the crystalline resin (b), or an alloy of the amorphous resin (a) and the amorphous resin (c).

[0020] Examples of the thermoplastic resin constituting the thermoplastic resin filament include polyester resins such as polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polytrimethylene terephthalate (PTT) resin, polyethylene naphthalate (PEN) resin, and liquid crystal polyester resin; polyolefin resins such as polyethylene (PE) resin, polypropylene (PP) resin, and polybutylene resin; styrene resins; polyoxymethylene (POM) resin; polyamide (PA) resin; polycarbonate (PC) resin; polymethyl methacrylate (PMMA) resin; polyvinyl chloride (PVC) resin; polyphenylene sulfide (PPS) resin; polyphenylene ether (PPE) resin; modified polyphenylene ether (PPE) resin; polyimide (PI) resin; polyamideimide (PAI) resin; polyetherimide (PEI) resin; polysulfone (PSU) resin; modified polysulfone (PSU) resin; polyethersulfone resin; polyketone (PK) resin; polyetherketone (PEK) resin; polyetheretherketone (PEEK) resin; polyetherketoneketone (PEKK) resin; polyarylate (PAR) resin; polyethernitrile resin; phenolic resins; phenoxy resins; fluorine-based resins such as polytetrafluoroethylene resin; and furthermore, thermoplastic elastomers such as polyurethane-based resins, polybutadiene-based resins, and polyisoprene-based resins, as well as copolymers and modified products thereof are used. Among the above thermoplastic resins, examples of the amorphous resin (a) include styrene resins, polycarbonate resins, polymethyl methacrylate resins, polyvinyl chloride resins, polyphenylene ether resins, modified polyphenylene ether resins, polyamideimide resins, polyetherimide resins, polyethersulfone resins, and polyurethane-based resins. Among the above thermoplastic resins, examples of the crystalline resin (b) include polyolefin resins such as polyethylene resins, polypropylene resins, and polybutylene resins, polyoxymethylene resins, polyamide resins, polyetheretherketone resins, and polytetrafluoroethylene resins. Among the above-mentioned thermoplastic resins, from the viewpoints of heat resistance and impact resistance, as the amorphous resin (a), a polyphenylene ether (PPE) resin is preferable. Further, when the thermoplastic resin contains a crystalline resin (b) in addition to the amorphous resin (a), a combination of a polyphenylene ether (PPE) resin and a polyamide (PA) resin is preferable. When two or more kinds of amorphous resins (a) are included, a combination of a polyphenylene ether (PPE) resin and a styrene-based resin is preferable. That is, in the present invention, the thermoplastic resin of the present embodiment contains at least the amorphous resin (a). It is preferable that the amorphous resin (a) contains a polyphenylene ether resin. Further, it is preferable that the thermoplastic resin contains a crystalline resin (b) in addition to the amorphous resin (a), and it is preferable that the crystalline resin (b) is a polyamide resin. When the thermoplastic resin contains two or more kinds of amorphous resins (a), it preferably contains a polyphenylene ether resin and a styrene-based resin.

[0021] The polyphenylene ether (PPE) resin in the present invention preferably has a structure represented by at least one of the following general formulas (I) and (II). That is, as the polyphenylene ether (PPE) resin, a homopolymer having a structural unit represented by the general formula (I) or (II), or a copolymer composed of these structural units can be used. [Chemical formula] (In formulas (I) and (II), R1, R2, R3, R4, R5, and R6 are monovalent residues such as an alkyl group having 1 to 4 carbon atoms, an aryl group, a halogen, or hydrogen, and R5 and R6 are not hydrogen at the same time.)

[0022] Typical examples of polyphenylene ether (PPE) homopolymers include homopolymers such as poly(2,6-dimethyl-1,4-phenylene) ether, poly(2-methyl-6-ethyl-1,4-phenylene) ether, poly(2,6-diethyl-1,4-phenylene) ether, poly(2-ethyl-6-n-propyl-1,4-phenylene) ether, poly(2,6-di-n-propyl-1,4-phenylene) ether, poly(2-methyl-6-n-butyl-1,4-phenylene) ether, poly(2-ethyl-6-isopropyl-1,4-phenylene) ether, poly(2-methyl-6-chloroethyl-1,4-phenylene) ether, poly(2-methyl-6-hydroxyethyl-1,4-phenylene) ether, and poly(2-methyl-6-chloroethyl-1,4-phenylene) ether.

[0023] Copolymers of polyphenylene ether (PPE) include polyphenylene ether copolymers mainly composed of a polyphenylene ether structure, such as copolymers of 2,6-dimethylphenol and 2,3,6-trimethylphenol, copolymers of 2,6-dimethylphenol and o-cresol, or copolymers of 2,6-dimethylphenol with 2,3,6-trimethylphenol and o-cresol. Further, this polyphenylene ether (PPE) preferably has a reduced viscosity (measured at 0.5 g / dl, chloroform solution, 30 °C) in the range of 0.15 to 2.0 g / dl. In addition to those described above, the polyphenylene ether (PPE) may also be a modified polyphenylene ether resin modified with an α,β-unsaturated carboxylic acid or its derivative such as maleic acid, maleic anhydride, fumaric acid, itaconic acid, acrylic acid, acrylic acid ester, methacrylic acid, or methacrylic acid ester.

[0024] Examples of polyamide (PA) resins include polycondensates of dibasic acids and diamines, ring-opening polycondensates of cyclic lactams, polycondensates of aminocarboxylic acids, and copolymers and blends thereof. More specifically, aliphatic amide resins such as polyamide 66, polyamide 46, polyamide 612, polyamide 610, polyamide 6, polyamide 11, polyamide 12, etc., semi-aromatic polyamide resins such as polymetaxylylene adipamide (polyamide MXD6), polyhexamethylene terephthalamide (polyamide 6T), polyhexamethylene isophthalamide (polyamide 6I), etc., and copolymers and blends thereof. Among these, from the viewpoints of heat resistance and mechanical properties, polyamide 66, polyamide 6, polyamide 66 / 6, and polyamide 66 / 6I are particularly preferably used as the polyamide resin.

[0025] Examples of styrene resins include GPPS (general-purpose polystyrene), HIPS (high-impact polystyrene), ABS (acrylonitrile-butadiene-styrene), SEBS (hydrogenated styrene-butadiene-styrene block copolymer), SBS (styrene-butadiene-styrene block copolymer), SEPS (hydrogenated styrene-isoprene-styrene block copolymer), etc. Particularly preferred are GPPS (general-purpose polystyrene) and HIPS (high-impact polystyrene), which are polystyrene resins. These styrene resins may be used alone or in combination of two or more.

[0026] Specific examples of commercially available products of polyphenylene ether (PPE) alloys include the "Zylon" series from Asahi Kasei Corporation, the "Noryl" series from SABIC Innovative Plastics, the "UpiAce" series and "Remaloy" series from Mitsubishi Engineering Plastics Corporation, etc.

[0027] In addition, the thermoplastic resin filament for a 3D printer of the present invention can have other resins and additives added thereto, such as elastomers, plasticizers, stabilizers, antistatic agents, ultraviolet absorbers, flame retardants, colorants, mold release agents, and fibrous reinforcing agents such as glass fibers, potassium titanate whiskers, and zinc oxide whiskers, and further fillers such as glass beads, glass flakes, mica, calcium carbonate, and talc, as long as the effects of the invention are not impaired.

[0028] (Shape of filament) The filament in the present embodiment is not particularly limited, but from the viewpoint of being used as a modeling material for a 3D printer using the fused deposition modeling method, it is preferably fibrous and composed of a single monofilament. The filament of the present embodiment has a wire diameter of 1.500 mm or more and 3.000 mm or less. When the wire diameter of the filament is 1.500 mm or more and 3.000 mm or less, it is suitable for a general-purpose 3D printer using the fused deposition modeling method. The wire diameter of the filament of the present embodiment is preferably 1.680 mm or more and 1.830 mm or less, and more preferably 1.700 mm or more and 1.800 mm or less.

[0029] The filament supplied to the 3D printer nozzle is in a solid state on the upstream side and in a molten liquid state on the downstream side (nozzle outlet side). The solid on the upstream side extrudes the molten liquid on the downstream side like a piston, and the molten resin is discharged from the discharge nozzle. Since the discharge flow rate is affected by a slight change in the distance between the filament and the inner diameter of the printer nozzle, in order to avoid nozzle clogging and to achieve stable formability and reduce the variation in the strength of the molded product, it is particularly preferable that the wire diameter is constant throughout the entire filament required for creating the molded product, and that the shape of the filament is close to a perfect circle.

[0030] The roundness of the filament of the present embodiment is preferably 1.030 or less, more preferably 1.020 or less, and even more preferably 1.010 or less. Also, the closer the roundness is to 1.0, the more preferable it is, but it may also be 1.005 or more. In addition, in this specification, the roundness of the filament is the ratio of the maximum value to the minimum value (major axis / minor axis), and can be measured by the following measurement method.

[0031] Whether the wire diameter is constant throughout the filament and whether the shape of the filament is close to a perfect circle can be evaluated by measuring the wire diameter and roundness and using the average value and standard deviation of the wire diameter, as well as the average value and standard deviation of the roundness. The average value and standard deviation of the wire diameter, and the average value and standard deviation of the roundness are measured by the following method. The wire diameter is measured while scanning the filament at a constant speed with a three-axis laser measuring machine ODAC 13TRIO manufactured by Zumbach. The measured values of the wire diameter measured on the X-axis, Y-axis, and Z-axis at each measurement point are calculated as (X + Y + Z) / 3 as the wire diameter average value (i). The wire diameter average value (ii) and the standard deviation of the wire diameter are calculated from the wire diameter average value (i) data of 5000 or more points in each of the three directions, and the process capability (wire diameter) is calculated according to the following formula (1). Process capability (wire diameter) = (wire diameter average value (ii) × 0.04) / (6 × standard deviation) ··· (1)

[0032] Furthermore, among the measured values measured on the X-axis, Y-axis, and Z-axis at each measurement point, the ratio of the maximum value to the minimum value (major axis / minor axis) is calculated as the roundness (i), and the roundness average value (ii) and the standard deviation of the roundness are calculated from the roundness (i) data of 5000 or more points, and the process capability (roundness) is calculated according to the following formula (2). Process capability (roundness) = (1.03 - roundness average value (ii)) / (3 × standard deviation) ··· (2) In this embodiment, the process capability (wire diameter) and the process capability (roundness) are each 1.33 or more, preferably 1.67 or more. In the manufacturing process of the filament, if the resin temperature of the filament is cooled below the glass transition temperature (Tg), the change amount of the wire diameter is very small. Therefore, the average value and standard deviation of the wire diameter, and the average value and standard deviation of the roundness may be calculated by adopting the values measured, for example, after the filament is cooled and before winding.

[0033] The standard deviation of the wire diameter is preferably 0.020 or less, more preferably 0.010 or less, and even more preferably 0.009 or less. Also, the standard deviation of the wire diameter may be 0.001 or more, or may be 0.004 or more.

[0034] The standard deviation of the roundness is preferably 0.020 or less, more preferably 0.010 or less, and even more preferably 0.050 or less. The standard deviation of the roundness may be 0.001 or more, or may be 0.002 or more.

[0035] <Method for Manufacturing Thermoplastic Resin Filament for 3D Printer> The method for manufacturing a thermoplastic resin filament for a 3D printer according to this embodiment is injecting the molten thermoplastic resin from a single-hole die to obtain a filament, and after injection, gradually cooling the filament at a rate of 15°C / second or less to a temperature below the glass transition temperature (Tg). With such a manufacturing method, as described above, by injecting the molten resin from a single-hole die, the generation of external force is prevented, and by gradually cooling the filament at a rate of 15°C / second or less to a temperature below the glass transition temperature (Tg) after injection, a filament with a stable wire diameter and roundness can be obtained throughout.

[0036] The method for manufacturing a thermoplastic resin filament for a 3D printer according to the present invention uses the above-described thermoplastic resin as a raw material. The thermoplastic resin filament for a 3D printer according to the present invention can be obtained by extruding the molten resin from a die using, for example, a single-screw or twin-screw extruder, then cooling it, and then winding it around a spool or the like. The thermoplastic resin filament of the present invention can be produced by melt-kneading using pellets prepared by conventionally known techniques such as a Brabender, a kneader, a Banbury mixer, an extruder, etc., as long as the content of the present invention is satisfied. Note that, by supplying various raw materials at a predetermined mixing ratio using an extruder and melt-kneading them, it is also possible to produce a filament as it is without producing pellets.

[0037] As a method for producing the thermoplastic resin filament for a 3D printer of the present invention, it is preferable to gradually cool the temperature of the filament to a temperature below the glass transition temperature (Tg) between when the molten resin is discharged from the die and when it reaches the take-up machine. If the filament is rapidly cooled, a temperature difference occurs between the surface and the inside of the filament, a shrinkage difference occurs between the inside and the surface of the filament, voids are generated inside the filament, and variations in the wire diameter and roundness increase. On the other hand, when the filament is gradually cooled, it is difficult for a shrinkage difference to occur between the inside and the surface of the filament, and variations in the wire diameter and roundness become small. Note that, compared to the case of producing a thermoplastic resin filament composed only of an amorphous resin, when producing a thermoplastic resin filament composed only of a crystalline resin, even if it is rapidly cooled after the molten resin is discharged from the die, the variations in the wire diameter and roundness do not tend to increase. This is presumably due to the fact that when comparing the temperature difference between the processing temperature and Tg of the amorphous resin and the temperature difference between the processing temperature and the crystallization temperature (Tc) of the crystalline resin, the temperature difference of the amorphous resin is larger, and the time required until the cooling is completed is longer for the amorphous resin.

[0038] Examples of the method for gradually cooling the filament include cooling only by air cooling, immersing the filament in a water bath filled with warm water, shortening the length of the filament immersed in cooling water, and a method of locally spraying cooling water onto the filament like a shower. On the other hand, methods such as immersing the filament in a water bath filled with cooling water, increasing the length of immersion in the water bath, and maintaining the temperature of the cooling water used in the water bath at a low temperature by a chiller are methods of rapidly cooling the filament. The rate of slow cooling is preferably 14° C. / sec or less, more preferably 10° C. / sec or less, at which the surface temperature of the filament is cooled. In the present invention, cooling at a rate of 15° C. / sec or less is called slow cooling, and cooling at a rate faster than 15° C. / sec is called rapid cooling.

[0039] In addition, in the cooling process of the filament, since there is a concern that the filament may deform at a temperature equal to or higher than Tg, it is preferable to avoid applying external forces other than in the direction of drawing the filament as much as possible until the filament is cooled to a temperature equal to or lower than Tg in order to obtain a filament with small variations in roundness and wire diameter. From the discharge port to the take-up machine, in order to prevent the filament from being subjected to external forces, for example, a method of isolating it from the outside by installing an enclosure around it, a method of installing a lid on the top of a cooling tank such as a water bath, a method of using a rotating roller as a guide to adjust the take-up direction of the filament and the immersion length in the cooling tank, etc. In addition, in order to prevent the roller from applying localized forces to the filament, a roller shape with deep grooves may be used, and in order to suppress deformation due to friction between the filament and the roller, a material with excellent sliding properties and heat resistance may be used as the material for the roller. When extruding a filament, if multiple strands are drawn simultaneously using multiple spinnerets, as is the case when extruding normal thermoplastic resin pellets, uneven cooling efficiency may occur between the strands, and localized external forces may be generated during drawing, causing deformation of the filament. Therefore, in order to obtain a filament with minimal variation in roundness and wire diameter, it is desirable to use a spinneret with one hole.

[0040] As described above, in the manufacturing method of the thermoplastic resin filament for 3D printers of the present invention, it is possible to prevent external forces from acting on the filament as much as possible before it is cooled below its glass transition temperature, and also to stabilize the wire diameter and roundness throughout the entire filament by slowly cooling the filament to a temperature below its glass transition temperature (Tg) after extrusion.

[0041] <modeled product> The shaped article of this embodiment uses the thermoplastic resin filament for a 3D printer of this embodiment. Since the filament having a stable wire diameter and roundness in this embodiment is used, it is possible to perform shaping continuously for a long time, and furthermore, a shaped article having excellent impact strength and little variation in impact strength is obtained. The shaped article of this embodiment is obtained by using the thermoplastic resin filament for a 3D printer of the present invention and molding it with a 3D printer.

Example

[0042] Hereinafter, the present invention will be described with reference to examples, but this embodiment is not limited to the following examples.

[0043] Those used in the examples, comparative examples, and reference examples are as follows. PPE+PS: Polyphenylene ether resin (amorphous resin) + polystyrene resin (amorphous resin), "Zylon 540Z" manufactured by Asahi Kasei Corporation PPE+PA: Polyphenylene ether resin (amorphous resin) + polyamide resin (crystalline resin), "Zylon AS100" manufactured by Asahi Kasei Corporation PA: Polyamide resin (crystalline resin), "Leonard 1300S" manufactured by Asahi Kasei Corporation

[0044] <Example 1> 100 parts of "Zylon 540Z" manufactured by Asahi Kasei Corporation was supplied to a single-screw extruder, melt-extruded at a cylinder temperature of 270°C, and discharged from a die having a round cross-sectional shape with a diameter of 2.5 mm and one hole. Cooling water at 30°C was sprayed onto the discharged filament, the filament was held in the air using a rotary roller, and the filament was taken up at a speed of 20 m / min to obtain a filament.

[0045] <Comparative Example 1> A filament was obtained in the same manner as in Example 1, except that the spraying of cooling water at 30°C onto the filament was changed to be after the roller came into contact with the filament.

[0046] <Comparative Example 2> A cooling bath with a length of 2 m was used for cooling the filament. Cooling water at 30°C was filled, and the operation was carried out in the same manner as in Example 1 except that it was immersed by 1 m, and a filament was obtained.

[0047] <Example 2> The operation was carried out in the same manner as in Example 1 except that the resin used was changed to 100 parts of "Zylon AS100" manufactured by Asahi Kasei Corporation, and a filament was obtained.

[0048] <Comparative Example 3> The operation was carried out in the same manner as in Comparative Example 2 except that the resin used was changed to 100 parts of "Zylon AS100" manufactured by Asahi Kasei Corporation, and a filament was obtained.

[0049] <Reference Example 1> The operation was carried out in the same manner as in Comparative Example 2 except that the resin used was changed to 100 parts of "Leonac 1300S" manufactured by Asahi Kasei Corporation, and a filament was obtained.

[0050] The methods for each measurement and evaluation in the examples and comparative examples are as follows.

[0051] (1) Filament wire diameter and roundness A three-axis laser measuring machine ODAC 13TRIO manufactured by Zumbach was installed between the cooling engineering section and the take-up machine during the production of the filament, and measurement was carried out under the following conditions. · Filament scanning speed: 20 m / min · Measurement speed (per axis): 600 data / second, (1 data every 0.0555 cm) · Measurement time: 100 minutes One wire diameter measurement value (the average value of 600 data measured at a length of 33.3 cm) per axis per second was output as one measurement value. The wire diameter measurement values measured on the X-axis, Y-axis, and Z-axis were used as (X + Y + Z) / 3 to calculate the wire diameter average value (i). From the obtained 6000 wire diameter average values (i), the wire diameter average value (ii) and the standard deviation of the wire diameter were calculated, and the process capability (wire diameter) was calculated according to the following formula (1). Process capability (wire diameter) = (wire diameter average value (ii) × 0.04) / (6 × standard deviation) ··· (1) Among the measured values measured on the X-axis, Y-axis, and Z-axis, the ratio of the maximum value to the minimum value (major axis / minor axis) was calculated as the roundness (i), and the average roundness value (ii) and the standard deviation of the roundness were calculated from the data of 6000 points of roundness (i). The process capability (roundness) was calculated according to the following formula (2). Process capability (roundness) = (1.03 - average roundness value (ii)) / (3 × standard deviation) ··· (2)

[0052] (2) Charpy impact value Each filament obtained in the examples, comparative examples, and reference examples was set in a 3D printer ("FUNMAT HT" manufactured by Intamsys), and a test piece of 80 × 10 × 4 mm was formed in the XY direction shown in FIG. 1 under the forming conditions in Table 1. Here, FIG. 1 is a diagram showing the XYZ directions of the test piece. In addition, two types of nozzle diameters of 0.25 mm and 0.40 mm were used, and the forming speed was performed under two conditions of 60 mm / s and 150 mm / s. The Charpy impact strength (notched) was measured with a 4J hammer in accordance with ISO179. The number of measurement samples was 5. The fracture states of the 5 samples were visually confirmed. If delamination was observed between layers in even one sample, it was regarded as having delamination between layers, and if no delamination was observed between layers in all 5 samples, it was regarded as having no delamination between layers. Here, the filament is melted by a 3D printer nozzle, discharged to a specified position, and repeatedly deposited in layers to perform lamination to form a three-dimensional shape. The delamination between layers described here refers to the occurrence of delamination between these layers.

[0053] (3) Discharge stability Each filament obtained in the examples, comparative examples, and reference examples was tested under the following two conditions using a discharge tester described in Appendix A of JIS K 6821. (i) Using a nozzle with a nozzle hole diameter of 0.4 mm, the total amount of 500 g of the filament was tested at a nozzle temperature of 300°C and a feed rate of 200 mm / min. (ii) Using a nozzle with a nozzle hole diameter of 0.2 mm, the total amount of 500 g of the filament was tested at a nozzle temperature of 300°C and a feed rate of 200 mm / min. When the operation of the ejection tester did not stop even once and the full amount was ejected continuously, it was designated as A. When the operation of the ejection tester, such as nozzle clogging, stopped halfway, it was designated as B.

[0054] The manufacturing conditions in the examples, comparative examples, and reference examples, and the results of each measurement and evaluation are shown in Table 1.

[0055]

Table 1

[0056] In Table 1, NB represents non-break.

[0057] As shown in Table 1, in Example 1 where the wire diameter and roundness were stable, the variation in impact strength was small, no delamination was observed, and the ejection test was also stable. On the other hand, in Comparative Example 1 with inferior roundness stability, the operation stopped halfway during the ejection stability test with a 0.2 mm nozzle. Furthermore, in Comparative Example 2 with inferior wire diameter stability, the variation in impact strength was large, delamination was observed, and the operation also stopped halfway in the ejection stability test. Similarly, in Example 2 where the wire diameter and roundness were stable, the variation in impact strength was small, there was no delamination, and the ejection test was stable. In contrast, in Comparative Example 3 with inferior stability of wire diameter and roundness, the operation stopped halfway in the ejection stability test. By obtaining a filament with a stable wire diameter and roundness made of a specific thermoplastic resin, it can be seen that a shaped product can be continuously shaped for a long time, and furthermore, a shaped product with excellent impact strength and little variation in impact strength can be obtained.

Industrial Applicability

[0058] According to the present invention, by obtaining a filament with a stable wire diameter and roundness made of a specific thermoplastic resin alloy, a shaped product can be continuously shaped for a long time, and furthermore, a shaped product with excellent impact strength and little variation in impact strength can be obtained. Therefore, it becomes possible to shape large parts with a 3D printer and use them for applications that require impact strength.

Claims

1. A thermoplastic resin filament for a 3D printer made of a thermoplastic resin containing an amorphous resin (a), wherein the filament has a wire diameter of 1.500 to 3.000 mm, the average value of the wire diameter of the filament and the process capability (wire diameter) calculated by the standard deviation satisfy the following formula (1): Process capability (wire diameter) = (average wire diameter × 0.04) / (6 × standard deviation) ≥ 1.33... (1) and the roundness of the filament = the process capability (roundness) calculated by the average value and standard deviation of (major axis) / (minor axis) satisfies the following formula (2): Process capability (roundness) = (1.03 - average roundness) / (3 × standard deviation) ≥ 1.33... (2) A thermoplastic resin filament for a 3D printer that satisfies the above conditions.

2. The thermoplastic resin filament for a 3D printer according to Claim 1, wherein the calculation of the process capability of each of the formulas (1) and (2) is performed using 5,000 or more measurement values.

3. The thermoplastic resin filament for a 3D printer according to Claim 1, wherein the amorphous resin (a) contains a polyphenylene ether resin.

4. Furthermore, the thermoplastic resin contains a crystalline resin (b), and the crystalline resin (b) contains a polyamide resin. The thermoplastic resin filament for a 3D printer according to Claim 3.

5. The thermoplastic resin filament for a 3D printer according to Claim 3, wherein the amorphous resin (a) further contains a styrene resin.

6. A shaped article using the thermoplastic resin filament for a 3D printer according to any one of Claims 1 to 5.

7. A method for manufacturing a thermoplastic resin filament for a 3D printer according to any one of Claims 1 to 5, comprising injecting a molten thermoplastic resin from a single-orifice die to obtain a filament, and after injection, slowly cooling the filament at a rate of 15°C / second or less to a temperature below the glass transition temperature (Tg). A method for manufacturing a thermoplastic resin filament for a 3D printer.

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