JP2017105153A - Molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding material having excellent handleability.SOLUTION: A first molding material comprises a long fiber bundle constructed by bundling a plurality of synthetic fibers, and a resin part which coats the long fiber bundle or with which the long fiber bundle is impregnated. A second molding material comprises a long fiber bundle constructed by bundling a plurality of synthetic fibers, and functional material, such as conductive material, carried on the long fiber bundle.SELECTED DRAWING: None

Description

  The present invention relates to a modeling material, and particularly to a modeling material that can be suitably used for a three-dimensional printer.

  The resin molded body is molded by various methods such as injection molding and extrusion molding, and is widely used in the fields of daily necessities and industrial fields. Rapid prototyping using a three-dimensional modeling machine typified by a three-dimensional printer (3D printer) has attracted attention as a method for obtaining a small number of various types of molded products. Recently, 3D pens have also been released as simpler modeling devices.

  Three-dimensional printer methods include hot melt lamination (FDM), stereolithography (SLA), and powder sintering lamination (SLS), and technological developments are underway for each. For personal use, FDM method modeling apparatuses are widely used, and monofilaments such as acrylonitrile-butadiene-styrene copolymer (ABS) and polylactic acid (PLA) are used as modeling materials.

  For example, Patent Document 1 discloses that an average diameter of 0.069 to 0.074 inches (about 1.75 to 1.90 mm) and a length of 20 feet (about 6) as materials for enabling high-precision modeling. 1 m) or more and a modeling material having a standard deviation in diameter of 0.0004 inches (0.01 mm) or less is disclosed.

JP 2005-523391 A

However, the modeling material comprised by the continuous linear resin molding (monofilament-like thing) as mentioned above is hard, and its handleability is not good. In particular, the molding material made of polylactic acid is particularly hard, and such a hard linear modeling material is wound from a state where it is wound around a bobbin, as soon as the winding tension is slightly relaxed. May be released and become scattered from the bobbin. Further, among polylactic acid modeling materials sold on the market, those that are not crystallized have a problem that they are easily broken during use.
Then, this invention makes it a subject to provide the modeling material with favorable handleability.

  The modeling material of the present invention is as follows.

  (1) A modeling material (first, comprising a long fiber bundling body formed by bundling a plurality of synthetic fibers and a resin portion coated and / or impregnated with the fiber bundling body Modeling material).

  (2) A modeling material (second modeling material) comprising a long-sized fiber bundling body configured by bundling a plurality of synthetic fibers and a functional material supported on the fiber bundling body ).

  (3) The modeling material according to (2), wherein the functional material contains a functional additive and a thermoplastic binder.

  (4) The modeling material according to (3) above, wherein the functional additive is a conductive additive.

  (5) The modeling material according to any one of (1) to (4) above, which is a modeling material for a three-dimensional printer.

  The first modeling material of the present invention is flexible because it is composed of an elongated fiber bundle formed by bundling a plurality of synthetic fibers, and the resin portion is coated on the fiber bundle. Or the impregnated fiber bundling body has an appropriate rigidity and durability, that is, it has both flexibility, rigidity and durability, and therefore as a modeling material In particular, it can be preferably used as a modeling material for a three-dimensional printer.

  Similarly, the second modeling material of the present invention is composed of a long-shaped fiber bundling body formed by bundling a plurality of synthetic fibers. A resin molded product exhibiting performance based on the functional material can be obtained.

  The modeling material of this invention contains the elongate fiber bundling body comprised by bundling a plurality of synthetic fibers.

  The synthetic fiber constituting the fiber bundle is not particularly limited, and examples thereof include thermoplastic synthetic fibers obtained by a melt spinning method, such as polyester fibers, polyamide fibers, polyolefin fibers, and polyvinylidene fluoride fibers. In addition, synthetic fibers obtained by a wet spinning method such as acrylic fibers and polyvinyl alcohol fibers can be used. Furthermore, high-strength, high elastic modulus and high heat-resistant fibers such as ultra high molecular weight polyethylene fibers called super fibers and aramid fibers are also included. Of these, polyester fibers, polyamide fibers, and polyolefin fibers can be suitably used because of the ease of adjusting the single fiber fineness and mechanical properties and the high versatility. In particular, polylactic acid is preferable because warpage is unlikely to occur, and poly-L lactic acid having a low D-form content is more preferable because it is less yellowish. In order to make it less yellowish, the D-form content is preferably less than 1.5 mol%. By adjusting the D-form content, the melting point of polylactic acid can be adjusted according to the temperature control of the printer. In addition, fiber blends of polymer blends or polymer alloys composed of two or more resins, or composite fibers of two or more resins into sea-island, core-sheath, and side-by-side types can be used as synthetic fibers. It is. In general, flame retardants, colorants, lubricants, weathering agents, antibacterial agents, antioxidants, heat resistance agents, and the like that are generally used may be added to the synthetic fibers as long as the effects of the present invention are not impaired.

  The synthetic fiber constituting the fiber bundle can take the form of monofilament, multifilament, spun yarn and the like. When a monofilament is used, its diameter and cross-sectional shape are not limited. When a multifilament is used, the diameter and cross-sectional shape of the single yarn are not limited, and the number of filaments and the total fineness can be set to arbitrary values. When using a spun yarn, the diameter, cross-sectional shape, presence or absence of crimping, etc. of the short fiber material used is not limited, and the number of twists and yarn counts as well as the presence or absence of twisting are not limited.

  The form of the synthetic fiber may be a continuous fiber only form, or a short fiber having a specific fiber length may be used. When short fibers are used, in addition to the above-described spun yarn, a mixed spun yarn obtained by mixing continuous fibers and short fibers may be used. Such spun yarn may be used as a bundle of synthetic fibers for obtaining braids or twisted yarns. When all of the plurality of fibers constituting the fiber bundle are continuous fibers, continuous fibers having different finenesses may be mixed. When continuous fibers having different finenesses are used, they may be in the form of a composite yarn in which the periphery of a filament with a high fineness is braided with a multifilament, or a composite yarn in which a periphery of a filament with a high fineness is wound with a multifilament.

  A composite fiber prepared by preparing a plurality of one or more kinds of synthetic fibers and combining them by means of drawing, twisting, blending, entanglement, etc. can also be used as a synthetic fiber. As for the spun yarn, a plurality of types of short fiber materials can be combined by blending.

  The fiber bundling body is a bundling of a plurality of synthetic fibers, and examples thereof include a twisted yarn, a braid, a rope, and a chain braid. By bundling a plurality of synthetic fibers, the modeling material can be configured more flexibly than a known modeling material for an FDM type three-dimensional printer composed of a single yarn. Troubles such as breakage due to bending load are suppressed.

  The synthetic fibers and / or fiber bundles may be heat-set by dry heat, steam, or the like. When two or more types of synthetic fibers having different melting points are used, a part of the fiber bundle is fused by heat setting at a temperature not less than the melting point of the low melting point synthetic fiber and not more than the high melting point synthetic fiber. It is also possible to adjust the mechanical strength such as rigidity and bending elastic modulus of the focusing body. Moreover, handling property improves by adhering between fibers and making it hard to unravel. Regarding the heat setting, it may be performed simultaneously with coating and impregnation of the resin portion described later, or before or after the processing of the resin portion.

  While a modeling material in which a plurality of synthetic fibers are converged to form a fiber bundling body is used in, for example, a three-dimensional printer, feeding and melting to the nozzle part occur continuously or intermittently, Since the tip portion is always melted, the converging body does not melt and be scattered during modeling. However, when the modeling material is set on the three-dimensional printer in the initial preparation stage, the workability deteriorates due to the unraveling because the tip portion is not melted. Therefore, it is also preferable to improve the convergence by bonding the fibers with a resin or by thermally bonding the constituent fibers.

  Examples of the method for bundling a plurality of synthetic fibers include a method of twisting, a method of making a string, a method of heat bonding by heat treatment, a method of entanglement, and a method of mixing fibers. More specifically, a method of twisting and converging a plurality of synthetic fibers, and a method of converging as a braid by using two or more bundles obtained by aligning or twisting a plurality of synthetic fibers , A method of bundling a plurality of synthetic fibers by heat-treating them to melt or soften a part of the thermoplastic resin constituting the synthetic fibers and thermally bonding the fibers together, a plurality of synthetic fibers Or a method in which these twists, strings, thermal bonding, and entanglement are combined.

  In the method in which a plurality of synthetic fibers are aligned and twisted to be bundled, in the case of single twisting, it is preferable to fix the twisted form by heat treatment because it is easy to unwind from the end. In the heat treatment, it is also preferable to heat-treat at a temperature at which a part of the thermoplastic resin constituting the fiber is melted or softened and to thermally bond the fibers to fix the form.

  It is also preferable that two or more single-twisted fiber bundles are twisted in a direction opposite to the single-twist and converged, and so-called various twists are applied to make it difficult to unwind. It is also preferable to heat-treat after twisting and fix the form by heat fixing or heat bonding. The twist direction of the single-stranded fiber bundle before various twists, that is, the direction of the lower twist is the same direction, that is, the fiber bundle twisted in the same direction is selected, and the number of times of the lower twist is appropriately adjusted according to the fineness Good.

  In the method of converging by using two or more fiber bundles to form a string, either flat punching, square punching, or round punching may be applied. As a continuous linear material generally used as a feed material for a three-dimensional printer of the hot melt laminating method, a braided cord by round punching is preferable because there are many circular cross sections. In the case of round punching, in order to obtain a more perfect circle shape, it is preferable to set it to 8 or more, more preferably 16 or more.

  The first modeling material of the present invention is obtained by coating and impregnating the above-described fiber bundle with a resin portion. This resin part is mainly composed of a thermoplastic resin, and is impregnated and / or impregnated into a fiber base material (a fiber bundle itself formed by bundling a plurality of fibers, or a synthetic fiber constituting the fiber bundle) by a wet or dry method. Covered. The material constituting the resin portion can be selected from various resins depending on the adhesiveness and workability with the synthetic fiber as the base material and the properties of the resulting composite and molded product. For example, polyolefin resin, acrylic resin, vinyl acetate resin, polyester resin, polyamide resin, vinyl chloride resin, vinylidene chloride resin, polytetrafluoroethylene resin, silicone resin, polyurethane resin, etc. are suitable. Can be used for It is also possible to use a mixture of a plurality of types of resins depending on the required performance. If necessary, other components may be added to the resin, such as fillers, plasticizers, flame retardants, colorants, lubricants, weathering agents, antibacterial agents, antioxidants, heat-resistant agents, and the like. You may add suitably in the range which does not impair. When processing by a wet method, for example, as a dispersion liquid in which the above resin is dispersed in a dispersion medium such as water or an organic solvent, the fiber base material is impregnated and / or coated by a method such as dipping or padding. Can do. In the case of processing by a dry method, for example, the above resin can be melted by heat and impregnated and / or coated by extrusion molding or pultrusion molding through a pore together with a fiber base material.

  The synthetic fiber constituting the fiber bundling body may be subjected to surface treatment such as grafting or plasma processing with an electron beam or radiation in order to enhance the adhesion to the resin part. Furthermore, in the fiber production process and / or the post-process, an appropriate fiber oil or coating agent may be applied or impregnated from the viewpoint of the above-mentioned adhesiveness.

  The composite obtained by the method as described above is formed by linearly forming a long fiber bundle by covering and / or impregnating a resin part, and is used for an FDM type three-dimensional printer. It can be used as a modeling material. That is, a resin molded product can be obtained by melting and molding this modeling material at a temperature equal to or higher than the melting point of the synthetic fiber constituting the fiber bundle and the thermoplastic resin constituting the resin portion.

  The composite as the modeling material is flexible because it is composed of a long fiber bundle formed by bundling a plurality of synthetic fibers, and the resin bundle is coated on the fiber bundle. Or the impregnated fiber bundling body is integrated to have an appropriate rigidity and durability, that is, a combination of flexibility, rigidity and durability, and thus a three-dimensional printer. It can be particularly preferably used as a modeling material for the purpose. That is, since it has appropriate flexibility, it is easy to handle. In addition, in order to have appropriate rigidity and durability, even if feeding is performed by a knurling type feeding device inside the three-dimensional printer, it can be fed satisfactorily and its surface is damaged by the knurling of the feeding device. It has the advantage that it is never done.

  In the second modeling material of the present invention, a functional material is supported on a fiber bundle. The functional material can include a functional additive. Examples of the functional additive include a conductive additive, a heat conductive additive, an antioxidant, a weathering agent, an antistatic agent, a dispersant, a lubricant, a flame retardant, a colorant, a fluorescent agent, and a phosphorescent agent. It is done. Short organic fiber, inorganic fiber and natural fiber are also included. The functional material preferably contains a thermoplastic binder in addition to the above functional additive in order to obtain an adhesive force with the fiber bundle.

  “Supporting” means a state in which the functional additive is not present inside the polymer constituting the fiber bundle by kneading or the like, but is integrally present on the outer surface thereof by adhesion or the like. . For example, when the functional additive is a conductive additive, the method of kneading the conductive additive makes it difficult to achieve both the mechanical properties and the conductive performance of the synthetic fiber. There is a limit to the amount. However, by supporting the conductive material on the fiber bundling body, the mechanical properties as a modeling material for an FDM type three-dimensional printer can be adjusted with synthetic fibers, and the conductivity as the obtained molded product is the structure and support of the conductive material. The amount can be adjusted, and the type and amount of the conductive material can be selected widely. The specific resistance value of the conductive material is preferably 10 7 Ω · cm or less. Examples of the conductive material include a material containing a conductive additive and a thermoplastic binder.

  The conductive additive can be selected from carbon, metal, ceramic, conductive polymer, and the like. Examples of carbon-based materials include conductive carbon black such as ketjen black, carbon fiber, and carbon nanotube (CNT). Examples of the metal-based material include single metal such as silver, copper, and zinc, or compound particles and fibrous materials. Examples of the ceramic system include materials such as silicon carbide and alumina. Examples of the conductive polymer include polythiophene compounds, polyaniline compounds, and polypyrrole compounds. Depending on the intended use and required performance of the molded product, the above conductive additives can be used alone or in a plurality of types.

  Other functional additives other than conductive additives include, for example, antioxidants, weathering agents, antistatic agents, dispersants, lubricants, flame retardants, colorants, antibacterial agents, heat conductive materials, fragrances, water-soluble Materials, smoothing agents, plasticizers, radiopaque agents, fillers, impact resistance improvers, crystal accelerators, compatibilizers and the like can be mentioned.

  Specifically, examples of the antioxidant include phenol-based, organic phosphite-based, organic phosphorus-based and thioether-based compounds such as eggplant.

  Examples of weathering agents include hindered amines, benzophenones, benzotriazoles, and benzoates.

  Examples of the antistatic agent include nonionic, cationic and anionic agents.

  Examples of the dispersant include bisamide-based, wax-based and organometallic salt-based ones.

  Examples of the lubricant include amide type, wax type, organometallic salt type, ester type and the like.

  Examples of the flame retardant include bromine-containing organic, phosphoric acid, antimony trioxide, magnesium hydroxide, ammonium phosphate, and red phosphorus.

  Examples of the coloring agent include pigments such as carbon black, titanium oxide, perylene, quinacridone, and phthalocyanine, and dyes such as azo, indigo, quinone, xanthene, and pyridone benzodifuranone. Examples include quinoline-based, pyridinone-based, organometallic-based fluorescent / phosphorescent pigments, and vanadium oxide, polydiacetylene-based, viologen-based chromic pigments, and the like.

  Examples of the antibacterial agent include silver, copper, silver-zeolite, photocatalytic titanium oxide, organic nitrogen sulfur compound, isothiazolone, carboxylic acid, and organometallic.

  Examples of the heat conductive additive include metals, carbons, ceramics, and silicate minerals.

  Examples of the fragrances include natural fragrances, synthetic fragrances, and compounds that generate fragrances. More specifically, there are animal flavors such as vegetable essential oils and musks, and synthetic flavors such as limonene and nerolidol.

  Examples of water-soluble materials include those based on polyvinyl alcohol, starch and acrylic acid.

  Examples of the smoothing agent include silicones, fluorines, and waxes.

  Examples of the plasticizer include phthalic acid, adipic acid, phosphoric acid, and wax.

  Examples of the radiopaque agent include barium sulfate, lead-based, tungsten-based and the like.

Examples of the filler include metal, carbon, glass, and cellulose.
Examples of the impact resistance improver include various polymers, elastomers, and core-shell impact resistance improvers.

  Examples of the crystallization accelerator include metal oxide, silicate, fatty acid ester, organic sulfonate, phosphate metal salt, glycerin, polyalkylene glycol, and the like.

  Examples of the compatibilizer include ethylene vinyl alcohol, styrene, ester, and amide.

  The thermoplastic binder functions as a matrix for the functional material and plays a role of adhering the fiber bundle and the functional material. The thermoplastic binder is composed of a thermoplastic resin material, but can be selected from various resins depending on the adhesiveness and workability with the synthetic fibers that make up the fiber bundle and the properties of the resulting composite and molded product. It is. For example, polyolefin resins, acrylic resins, vinyl acetate resins, polyester resins, polyamide resins, vinyl chloride resins, polytetrafluoroethylene resins, silicone resins, polyurethane resins and the like can be suitably used. Depending on the required performance, it is possible to mix a plurality of types of resins to form a thermoplastic binder.

  The mixing ratio of the functional additive and the thermoplastic binder in the functional material is not particularly limited, and the mass ratio of the functional material to the fiber bundle is not particularly limited, either of which can be freely set depending on the application and required performance. .

  You may add another functional additive to a functional additive as needed.

  The method for supporting the functional material on the fiber bundle is not particularly limited, and generally used processing means can be applied. For example, a technique of immersing and drying a fiber bundle in a dispersion containing a functional additive and a thermoplastic binder, a technique of coating, and the like can be given. If necessary, the loading amount of the functional material can be increased by repeating the technique for loading. In addition to the process of supporting the functional material on the fiber bundle, it is also possible to form the fiber bundle using synthetic fibers carrying the functional material. The composite outer layer obtained by supporting the functional material on the fiber bundle may be further coated with other synthetic fibers or binders depending on the purpose. By doing so, a protective film against external force such as friction can be configured.

  As the synthetic fiber constituting the fiber bundling body, a synthetic fiber subjected to bulk processing or crimping processing can be suitably used in order to structurally improve the adhesive force and carrying amount with the functional material.

  Such a composite can be used as a modeling material for an FDM type three-dimensional printer, and is molded by melting and molding at a temperature equal to or higher than the melting point of the synthetic fiber and the thermoplastic binder, thereby forming a resin having functionality such as conductivity. Goods can be obtained. Moreover, the functionality of a part or the whole of a molded product can be adjusted by using composite materials having different configurations and modeling materials having no functional material. Examples of the method of mixing modeling materials include a method of supplying materials simultaneously or sequentially to one feeder of an FDM type three-dimensional printer, and a method of supplying materials separately to a plurality of feeders. This composite is also applicable to 3D pens.

  The thermoplastic binder corresponds to the resin portion in the first modeling material. Therefore, the second modeling material can exhibit a specific technical effect of having a functionality such as conductivity after exhibiting the same performance as the first modeling material.

Example 1
Polylactic acid (melting point: 170 ° C., D-form content: 1.4 mol%) was melt-spun to obtain a polyester fiber of 560 dtex / 96 f. A polyester string having a diameter of about 1.75 mm was produced as a fiber bundle by using five polyester fibers aligned to form eight corners.

  A treatment liquid containing 15% by mass of a urethane resin having a flow start temperature of 170 ° C. as a binder component was used, and the above-described fiber bundle was immersed in this treatment liquid to hold the dispersion. Then, after adjusting the amount of dispersion held by squeezing with a mangle, the dispersion is introduced into a pin tenter type heat treatment apparatus, dried at 130 ° C. for 2 minutes, and a resin layer is formed on the surface of the polyester fiber, thereby forming a model. Obtained material. The mass ratio of the resin layer to the fiber bundle was 7.5% by mass.

  1 kg of the obtained modeling material was wound around a bobbin having an inner diameter of 100 mm. As a result, the modeling material was flexible and could be wound up neatly. Further, the above modeling material was introduced into an FDM type three-dimensional printer (Abby Co., SCOOVO C170), and a cube having a modeling temperature of 230 ° C., a stacking pitch of 0.1 mm, a density of 100%, and a piece of 3 cm was produced. As a result, it was possible to output beautifully, and a glossy molded product was obtained. A portion of the modeling material fed into the three-dimensional printer that was fed by knurling but not melted was observed. As a result, the feeding device performed the feeding operation satisfactorily without any problem.

(Example 2)
An aqueous dispersion of carbon nanotubes (CNT) (containing 2.3% by mass of multi-walled CNT as CNT and 15% by mass of urethane resin having a softening point of 150 ° C. as a binder component) was used as the treatment liquid. The same fiber bundling body as in Example 1 is immersed in this treatment liquid to hold the dispersion liquid, and the amount of the dispersion liquid is adjusted by squeezing with a mangle, and then introduced into a pin tenter type heat treatment apparatus at 130 ° C. for 2 minutes. Was dried. As a result, a conductive material containing CNTs was carried on the surface of the polyester fiber to obtain a modeling material. In this modeling material, the ratio of the conductive material to the fiber bundle was 8.5% by mass.

When the resistance value R (Ω) of the obtained modeling material was measured using a tester and the specific resistivity R ′ (Ω · cm) was calculated from the following equation, the value was approximately 10 2 Ω · cm. there were.
R ′ = R × S / L (S: cross-sectional area of specimen, L: distance between electrodes)

  When 1 kg of the obtained modeling material was wound around a bobbin having an inner diameter of 100 mm in the same manner as in Example 1, the modeling material was flexible and could be wound up neatly. Further, when a cube was produced under the same conditions as in Example 1, it was possible to output neatly and obtain a glossy product.

(Example 3)
A silver dispersion (containing 20% by mass of silver and 2% by mass of vinyl chloride binder) was used as the treatment liquid. The same fiber bundle as in Example 1 is immersed in this treatment liquid to hold the dispersion liquid, and the amount of the dispersion liquid is adjusted by squeezing with a mangle, and then introduced into a pin tenter type heat treatment apparatus. Dry for a minute. Thereby, modeling material was obtained by making silver carry on the surface of a polylactic acid fiber. In this modeling material, the ratio of the silver carrying layer in the fiber bundle was 8.5% by mass.

Example 4
As the treatment liquid, a water-based paint of conductive polymer (containing PEDOT (poly3,4-ethylenedioxythiophene) / PSS (polystyrene sulfonic acid)) was used. The same fiber bundle as in Example 1 is immersed in this treatment liquid to hold the dispersion liquid, and the amount of the dispersion liquid is adjusted by squeezing with a mangle, and then introduced into a pin tenter type heat treatment apparatus. Dry for a minute. Thereby, modeling material was obtained by carrying a conductive polymer on the surface of polylactic acid fiber. In this modeling material, the ratio of the conductive polymer in the fiber bundle was 1% by mass.

(Example 5)
An aqueous dispersion of a weathering agent (containing 7% by mass of a benzotrial compound and 7% by mass of a urethane resin having a softening point of 150 ° C.) was used as the treatment liquid. The same fiber bundle as in Example 1 is immersed in this treatment liquid to hold the dispersion liquid, and the amount of the dispersion liquid is adjusted by squeezing with a mangle, and then introduced into a pin tenter type heat treatment apparatus. Dry for a minute. Thereby, the modeling material was obtained by carrying a weathering agent on the surface of the polylactic acid fiber. In this modeling material, the ratio of the weathering agent-containing resin layer in the fiber bundle was 6% by mass.

(Example 6)
An aqueous dispersion of an antibacterial agent (containing 7% by mass of a silver-zeolite antibacterial agent and 7% by mass of a urethane resin having a softening point of 150 ° C.) was used as the treatment liquid. The same fiber bundle as in Example 1 is immersed in this treatment liquid to hold the dispersion liquid, and the amount of the dispersion liquid is adjusted by squeezing with a mangle, and then introduced into a pin tenter type heat treatment apparatus. Dry for a minute. Thereby, the modeling material was obtained by carrying | supporting an antibacterial agent on the surface of a polylactic acid fiber. In this modeling material, the ratio of the antibacterial agent-containing resin layer in the fiber bundle was 6% by mass.

  When the handleability of the modeling material of Examples 1-6 was evaluated, all these modeling materials were flexible and could be wound up neatly. Moreover, when it used for the evaluation test of the modeling property by 3D printer, any modeling material was able to output neatly and the molded product with a glossy feeling was obtained. In each modeling material fed into the inside of the three-dimensional printer, a portion that was fed by knurling but was not melted was observed. As a result, all of the modeling materials were successfully fed without any problem by the feeding device.

(Comparative Example 1)
Polylactic acid (melting point: 170 ° C., D-form content: 1.4 mol%) was melt-spun with an extruder-type spinning machine and stretched. As a result, a polylactic acid monofilament of 30000T (diameter: about 1.75 mm) having a strength of 3.5 cN / dtex and an elongation of 28% was obtained.

  As in Example 1, the obtained modeling material was wound around 1 kg on a bobbin having an inner diameter of 100 mm. It was hard and therefore difficult to wind, and when the winding force was weakened, it was separated from the bobbin and scattered. .

(Comparative Example 2)
A modeling material manufactured by ProtoPasta (trade name “Conductive PLA” made of PLA resin with conductive carbon) was used. If it is bent by hand, it easily breaks and is difficult to use with a three-dimensional printer.

Claims (5)

  A modeling material comprising a long fiber bundle formed by bundling a plurality of synthetic fibers, and a resin portion coated and / or impregnated with the fiber bundle.   A modeling material comprising a long fiber bundling body constituted by bundling a plurality of synthetic fibers and a functional material supported on the fiber bundling body.   The modeling material according to claim 2, wherein the functional material contains a functional additive and a thermoplastic binder.   The modeling material according to claim 3, wherein the functional additive is a conductive additive. The modeling material according to any one of claims 1 to 4, wherein the modeling material is a modeling material for a three-dimensional printer.