JP2016165884A - Molding material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a molding material applicable to a general-purpose 3D printer, in which additives such as various pigments can be easily added.SOLUTION: The molding material to be used for a hot-melt layering 3D printer is in a form of a single continuous thread by bundling a plurality of thermoplastic synthetic fibers. At least a part of the plurality of thermoplastic synthetic fibers contains a functional additive. The functional additive is, for example, a colorant.SELECTED DRAWING: None

Description

  The present invention relates to a modeling material used when a three-dimensional structure is obtained using a hot melt lamination method 3D printer.

  3D printers that create three-dimensional printers based on computer drawings can easily produce plastic parts, jigs, and products without using molds or melting equipment. It is rapidly spreading. In particular, a low-cost version of a 3D printer using a hot melt lamination method using a thermoplastic resin as a modeling material has been sold and has begun to spread to individuals.

  As a modeling material used for such a hot melt lamination method 3D printer, a linear resin molded product (monofilament-like product) made of a thermoplastic resin having a diameter of several millimeters in the longitudinal direction is commercially available and used. . For example, in Patent Document 1, as a highly accurate modeling material, the average diameter is 0.069 to 0.074 inch (about 1.75 to 1.90 mm), the length is 20 feet (about 6.1 m) or more, A build material (feed material) having a standard deviation in diameter of 0.0004 inches (0.01 mm) or less is disclosed. Further, as a thermoplastic resin constituting such a modeling material, a thermoplastic resin such as ABS resin, polycarbonate, polyamide, polylactic acid is used.

  In addition, when creating a model using such a material, if you want to color the model with a desired color, you can use a commercially available modeling material colored in that color. In many cases, a modeling material having a desired color cannot be obtained. Patent Document 2 discloses an apparatus for obtaining a multicolored shaped object. According to Patent Document 2, by providing a print head for coating an additive such as a stored pigment in front of a melt extrusion nozzle in a 3D printer apparatus, a shaped object whose surface is colored in a desired color is obtained. Can do.

  When a commercially available modeling material colored in a desired color is not available, a modeled object colored with a pigment of a desired color may be obtained by using a 3D printer device such as Patent Document 2. However, since the apparatus as disclosed in Patent Document 2 is complicated and expensive, it cannot be applied to a commercially available printer.

JP 2005-523391 A Special table 2014-516829 gazette

  The modeling material composed of the above-mentioned continuous linear resin molded product (monofilament-shaped material) is hard and cannot be said to be easy to handle. Among them, the modeling material composed of polylactic acid is particularly hard, and such a rigid modeling material is From the state of being hit by a bobbin etc., the state of being hit as soon as the squeezing tension is slightly released will be released and will be scattered and separated from the bobbin (this state is called “crash occurrence” Also called.) Further, among the polylactic acid modeling materials sold on the market, those that have not been crystallized have a problem that they are easily broken during use.

  In view of such a situation, the present inventor has studied to provide a modeling material for a hot melt lamination method 3D printer with good handleability. It was common knowledge to use a so-called monofilament-like material for the hot melt lamination method 3D printer material. However, while considering that other forms could be applied without being caught by the common sense, Invented a molding material in the form of one continuous thread by bundling synthetic fibers (Japanese Patent Application No. 2015-24247). And, through various studies using this invention, additives such as pigments can be easily added, and a modeling material that can be applied to a general-purpose 3D printer can be easily provided. As a result of study, the present invention has been reached. An object of the present invention is to provide a modeling material that can be applied to a general-purpose 3D printer, and to which additives such as various pigments can be easily added.

The present invention is a modeling material used for a hot melt lamination method 3D printer, the form of which is a continuous thread-like form in which a plurality of thermoplastic synthetic fibers are focused,
The gist of the present invention is a modeling material in which at least some of the plurality of thermoplastic synthetic fibers contain a functional additive.

  Hereinafter, the present invention will be described in detail.

  In the present invention, the modeling material used for the hot melt laminating method 3D printer is a material for supplying a hot melt laminating method 3D printer to obtain a three-dimensional modeled object, and is composed of a thermoplastic resin. Using this modeling material, based on the design drawing on the computer, with the modeling head, the thermoplastic resin constituting the modeling material is melted by heating, and injected and laminated from the nozzle to obtain a three-dimensional modeled object of the desired shape Create it.

  The modeling material of this invention is comprised with a thermoplastic synthetic fiber. As the thermoplastic resin constituting the synthetic fiber, any thermoplastic resin can be used as long as it can be melted at the melting temperature of the modeling head in the hot melt lamination method 3D printer. Examples thereof include polyester resins, aromatic polyester resins, polyamide resins, polyolefin resins, acrylic resins, polycarbonate resins, acrylonitrile-butadiene-styrene copolymer resins, and fluorine resin resins. A mixture of these resins may be used. Among them, 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 difficult to be yellowish. By adjusting the D-form content, the melting point of the polylactic acid can be adjusted according to the temperature control of the printer, but in order to make it less yellowish, the D-form content is less than 1.5%. Things are good. In addition, the method for producing the synthetic fiber using the above-mentioned resin is not particularly limited. However, when the fiber is produced using a crystalline thermoplastic resin, the stretching process and the heat shrinkage are controlled. A relaxation process for applying the process may be applied during the manufacturing process.

  In the modeling material of the present invention, a plurality of thermoplastic synthetic fibers are bundled to form a single continuous thread form. Examples of the method of 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, and the like. 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 focusing by fusing or softening a part of the thermoplastic resin constituting the synthetic fiber by heat-treating a plurality of synthetic fibers arranged together, or by thermally bonding the fibers together, or these ( A combination of twisting, string making, and thermal bonding).

  As described above, the modeling material of the present invention is formed by converging a plurality of thermoplastic synthetic fibers, and at least some of the plurality of thermoplastic synthetic fibers contain a functional additive. To do. As a functional additive, in order to give a desired function to a three-dimensional structure to be created, it is added to a modeling material that is a material, and includes an antioxidant, a weather resistance agent, an antistatic agent, and a dispersant. , Lubricant, flame retardant, colorant, antibacterial agent, heat conductive material, conductive material, fragrance, water-soluble material, smoothing agent, plasticizer, radiopaque agent, filler, impact resistance improver, crystal accelerator And compatibilizers.

More specifically, examples of the additive include an antioxidant, an organic phosphorus type such as a phenol type, an organic phosphite type, and a nasite, and a thioether type.
Examples of weathering agents include hindered amines, benzophenones, benzotriazoles, and benzoates.
Examples of the antistatic agent include nonionic, cationic, and anionic.
Examples of the dispersant include bisamide-based, wax-based, and organic metal salt-based ones.
Examples of the lubricant include amides, waxes, organometallic salts and esters.
Examples of the flame retardant include bromine-containing organic, phosphoric acid, antimony trioxide, magnesium hydroxide, ammonium phosphate, and red phosphorus.
Examples of the colorant include pigments such as carbon black, titanium oxide, perylene, quinacridone, and phthalocyanine, and dyes such as azo, indigo, quinone, xanthene, and pyridone benzodifuranone. Further, fluorescent / phosphorescent dyes such as quinoline, pyridinone, and organometallic, and chromic dyes such as vanadium oxide, polydiacetylene, and viologen can also be used.
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 material include metal, carbon, ceramic, and silicate mineral.
Examples of the conductive material include a metal system, a carbon system, a ceramic system, a conductive polymer system, and a surfactant.
Examples of the fragrances include natural fragrances, synthetic fragrances, compounds that generate fragrances, and more specifically, animal fragrances such as vegetable essential oils and musks, and synthetic fragrances such as limonene and nerolidol.
Examples of the water-soluble material include polyvinyl alcohol, starch and acrylic acid.
Examples of the smoothing agent include silicone, fluorine, and wax.
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 other types of polymers, elastomers, and core-shell impact resistance improvers.
Examples of the crystallization accelerator include metal oxide, silicate, fatty acid ester, organic sulfonate, phosphate ester metal salt, glycerin, and polyalkylene glycol.
Examples of the compatibilizer include ethylene vinyl alcohol, styrene, ester, and amide.

  These additives having functionality are contained in the thermoplastic synthetic fiber constituting the modeling material. As a method for inclusion, for example, one or two or more of the above-described additives may be combined as appropriate in the step of producing a thermoplastic polymer composition to be a synthetic fiber material. The blending of these additives may be adjusted by mixing at a predetermined ratio using a kneading apparatus such as a conventionally known single- or twin-screw extruder Banbury mixer, kneader, mixing roll, and melt-kneading the mixture. Alternatively, a so-called master batch having a high concentration may be prepared and used after being diluted.

  Moreover, it can also be made to contain by mix | blending an additive with the synthetic fiber or the synthetic | combination body of a plurality of synthetic fibers by immersing or exhausting an additive by a post process. For example, if it is a pigment | dye, it can be made to carry | support on the surface and the inside of a synthetic fiber by conventionally well-known methods, such as vat dyeing and washer dyeing. In dyeing, auxiliary agents such as carriers, leveling agents, and pH adjusters can be used as necessary, and refining, soaping, and fixing steps can be added.

  In addition, what is necessary is just to set content of a functional additive as the quantity which can exhibit a desired function, and should just design suitably according to the kind etc. of an additive.

  Of the plurality of thermoplastic synthetic fibers constituting the modeling material, all the synthetic fibers may contain a functional additive. Moreover, only some synthetic fibers may contain a specific functional additive. Furthermore, a plurality of synthetic fibers constituting the modeling material shall include different additives, and a plurality of synthetic fibers including different additives may be converged to include a plurality of types of additives as a modeling material. Good. Thus, the amount of the functional additive contained in the modeling material can be easily adjusted to a desired amount by appropriately combining the synthetic fiber containing the additive and the synthetic fiber not containing the additive. Also, by combining and converging synthetic fibers containing specific additives, a modeling material that can impart various functions can be obtained, and a three-dimensional structure that can easily exhibit various functions can be obtained. it can.

  In the present invention, as a specific method for bundling a plurality of synthetic fibers, the method described in the invention proposed by the present applicant (Japanese Patent Application No. 2015-24247) may be applied. Describe.

  In the method in which a plurality of synthetic fibers are aligned and twisted and bundled, in the case of single twisting, it is easy to unravel from the end portion, and therefore it is preferable to fix the twisted form by performing heat treatment. In the heat treatment, it is also preferable to perform the treatment 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. In addition, even if it is twisted yarn other than a single twist, it is possible to adjust a texture and to improve the focusing density between fibers by heat treatment.

  It is also preferable that two or more fiber bundles formed by single twisting are twisted in a direction opposite to the direction of single twisting and converged, and so-called various twists are applied to make it difficult to unwind. Furthermore, after twisting, it is also preferable to heat-treat and fix the form by heat fixing or heat bonding. As the twist direction (the direction of the lower twist) of the fiber bundle formed by the single twist before the various twists, 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. Although it is good, about 50 to 1000 times / m is preferable. The number of twists (top twists) may be appropriately designed according to the thickness and number of fiber bundles used.

  In the method of bundling by using two or more fiber bundles for stringing, either flat punching, square punching or round punching may be applied. In particular, braided braids are preferred because many continuous linear materials having a circular cross section are currently used as feed materials for hot melt lamination method 3D printers. In the case of round punching, in order to obtain a more perfect circle shape, it is preferable to use four or more strikes, more preferably eight or more strikes, and still more preferably 16 strikes. Moreover, as a form of a round string, a braid of a form in which a core thread is inserted into the center part in the longitudinal direction (axial direction) of the braid and a plurality of threads are arranged as side threads around the core thread. Is preferably adopted. This is because, in the cross section of the resulting modeling material, the density of the central portion is also dense, and a void portion is difficult to occur.

  The braid is also the same as the above-described twisted yarn, and it is also possible to adjust the texture and improve the convergence density between fibers by performing a heat treatment.

  When the molding material in which a plurality of thermoplastic synthetic fibers of the present invention are converged is set and used in a 3D printer, the end surface is melted and cut, so that the converged state is not broken and does not vary. . However, after mixing fibers made of a low-melting thermoplastic synthetic resin as a thermoplastic synthetic fiber to be bundled and bundling by twisting or stringing, heat treatment is performed at a temperature at which the low-melting thermoplastic synthetic resin melts, It is also preferable to improve the convergence by making a thermoplastic synthetic resin having a low melting point function as a thermal adhesive and thermally bonding the constituent fibers. Moreover, the density of a modeling material becomes dense by mixing a low melting point thermoplastic synthetic fiber and heat-bonding, and shape retention property also improves.

  In the present invention, continuous fibers may be selected as the form of the thermoplastic synthetic fiber, but short fibers having a specific fiber length may be used. When short fibers are used, a continuous yarn-shaped modeling material obtained by converging a spun yarn obtained by spinning a short fiber group or a mixed spun yarn formed by mixing continuous fibers and short fibers may be used. Such spun yarns may be used as a bundle of thermoplastic synthetic fibers for obtaining braids and plied yarns. Moreover, you may use the processed thread | yarn which consists of continuous fibers. Examples of the processed yarn include air entangled yarn, false twisted yarn, and BCF (Bulked Continuous Filament).

  Even when all the continuous fibers are selected as the plurality of fibers constituting the modeling material, continuous fibers having different fineness may be mixed. When continuous fibers having different fineness are used, 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 is used as the continuous yarn-like shape of the present invention. It can also be set as one form of modeling material. Monofilament yarn can also be used as the filament having a high fineness. For example, by arranging the monofilament yarn at the center of the modeling material, the density of the center becomes uniform. In addition, if a monofilament yarn having a low-melting-point thermoadhesive component on the fiber surface is placed in the center of the modeling material, heat treatment is applied to the surrounding fibers so that they can be well integrated and focused preferable.

  The single fiber fineness of the thermoplastic synthetic fiber may be appropriately designed in consideration of the number of yarns at the time of bundling, the diameter of the modeling material, the density at the time of bundling, and durability. For example, when the single fiber fineness is large, the durability against friction and the like is high, but there is a possibility that a gap between fibers becomes large and a void is generated during modeling. In addition, the cross-sectional shape of the single fiber may be appropriately designed in consideration of the handleability and the density when converging. For example, a round shape, an oval shape, a polygonal shape (triangle, square, etc.), a multileaf shape (cross shape, star shape, etc.), etc. may be mentioned, and fibers having different cross-sectional shapes may be used in combination.

  According to the present invention, it is possible to provide a modeling material for a hot melt lamination method 3D printer that is flexible and has good handleability, and the amount of the functional additive contained in the modeling material can be easily set to a desired value. By adjusting the amount and combining synthetic fibers containing additives, it is possible to obtain a modeling material that can give various functions, and a three-dimensional model that can easily exhibit various functions. Can be obtained.

Next, the present invention will be specifically described with reference to examples.
The physical properties of the fiber were tested according to JIS-L-1013. For handling, 1 kg was wound around a bobbin having an inner diameter of 100 mm for evaluation. As for the evaluation test of the 3D printer, a cube having a modeling temperature of 230 ° C., a stacking pitch of 0.1 mm, a density of 100%, and a side of 3 cm was prepared using an Abbey SCOOVO C170, and the appearance was confirmed.

Example 1
A polylactic acid chip (manufactured by Nature Works (6201D): D body content: 1.4%) is mixed with 10% by mass of carbon black and 1% by mass of copper iodide to produce a master chip, and 4 parts by mass of this master chip And 96 parts by mass of the above-mentioned polylactic acid chip (manufactured by Nature Works (6201D)), melt-spun using an extruder-type spinning machine, and stretched to give a strength of 4.0 cN / dtex and an elongation of 30% 1900 dtex. A multifilament made of / 210f original polylactic acid fiber was obtained. The multifilament made of the polylactic acid fiber was stringed by a 16 round punching machine, and then heat-set at 100 ° C. for 2 minutes to obtain the modeling material of Example 1.

Example 2
Using a polylactic acid chip (manufactured by Nature Works (6201D): D body content: 1.4%), melt spinning with an extruder-type spinning machine and drawing, the strength is 4.0 cN / dtex, and the elongation is 30%. A colorless multifilament made of 1900 dtex / 210f polylactic acid fiber was obtained.
The eight colorless multifilaments made of the polylactic acid fiber and the eight multifilaments made of the original polylactic acid fiber used in Example 1 were made with a 16 round punching machine, and then 100 ° C. for 2 minutes. Then, the heat setting was performed to obtain the modeling material of Example 2.

Example 3
Twelve colorless multifilaments made of polylactic acid used in Example 2 and four multifilaments made of original polylactic acid fiber used in Example 1 were made with a 16 round punching machine, and then Heat setting was performed at 100 ° C. for 2 minutes to obtain the modeling material of Example 3.

Comparative Example A polylactic acid chip (manufactured by Nature Works (6201D): D body content: 1.4%) was melt-spun and stretched with an extruder-type spinning machine, and the strength was 3.5 cN / dtex and the elongation was 28% 30000 dtex (diameter: about 1.75 mm) polylactic acid monofilament was obtained.

  Table 1 shows the evaluation results of Examples 1 to 3 and the comparative example. The modeling material of the present invention was applied to a hot melt laminating method 3D printer to obtain a good three-dimensional three-dimensional molded product, and was more flexible and handleable than the monofilament of the comparative example. In addition, as a combination of multifilaments constituting the modeling material, by adjusting the number of colored multifilaments as appropriate, the amount of the colorant contained as the modeling material can be adjusted. It was confirmed that it was possible to provide easily.

Example 4
Using a polylactic acid chip (manufactured by Nature Works (6201D): D body content: 1.4%), melt spinning and stretching with an extruder-type spinning machine, a colorless multi-layer made of polylactic acid fibers of 560 dtex / 96 filaments A filament was obtained.
On the other hand, the following fiber was obtained as a fiber containing a functional additive. That is, the above-mentioned polylactic acid chip and carbon black as a colorant were melt-kneaded with a twin-screw extruder to obtain a kneaded chip. At this time, the compounding amount of carbon black was 0.5% by mass in the kneading chip. This kneaded chip was melt-spun with an extruder-type spinning machine and drawn to obtain a monofilament containing a colorant of 560 dtex / 1f.

  The obtained fiber bundle in which three multifilaments and two monofilaments are aligned is twisted using a ring twisting machine at a Z twist of 60 times / m (Z-60) to obtain a twisted yarn. 7 were bundled and subjected to top twisting at a S twist of 150 times / m (S-150) using a ring twisting machine to obtain various twisted yarns. The various plied yarns were heat-treated at 165 ° C. for 1 minute to obtain the modeling material of Example 4 having a wire diameter of 1.75 mm. In the obtained modeling material, the constituent fibers were solidified by softening and shrinkage during heat treatment.

Example 5
In Example 4, the modeling material of Example 5 was obtained like Example 4 except having used the following fibers as a fiber containing a functional additive. In the obtained modeling material, the constituent fibers were solidified by softening and shrinkage during heat treatment.
A fiber containing a functional additive was obtained as follows. That is, the polylactic acid chip used in Example 4 and silver-zeolite as an antibacterial agent were melt-kneaded with a twin-screw extruder to obtain a kneaded chip. At this time, the compounding quantity of silver-zeolite was 5 mass% in the kneading chip. This kneaded chip was melt-spun with an extruder-type spinning machine and drawn to obtain a monofilament containing an antibacterial agent of 560 dtex / 1f.

Example 6
In Example 4, the modeling material of Example 6 was obtained in the same manner as in Example 4 except that the following fibers were used as the fibers containing the functional additive. In the obtained modeling material, the constituent fibers were solidified by softening and shrinkage during heat treatment.
A fiber containing a functional additive was obtained as follows. That is, the polylactic acid chip used in Example 4 and conductive carbon black as a conductive material were melt-kneaded with a twin-screw extruder to obtain a kneaded chip. At this time, the compounding amount of the conductive carbon black was 10% by mass in the kneading chip. This kneaded chip was melt-spun with an extruder-type spinning machine and drawn to obtain a monofilament containing a conductive material of 560 dtex / 1f.

Example 7
In Example 4, the modeling material of Example 7 was obtained in the same manner as in Example 4 except that the following fibers were used as the fibers containing the functional additive. In the obtained modeling material, the constituent fibers were solidified by softening and shrinkage during heat treatment.
A fiber containing a functional additive was obtained as follows. That is, the polylactic acid chip used in Example 4 and barium sulfate as an X-ray impermeable agent were melt-kneaded with a twin-screw extruder to obtain a kneaded chip. At this time, the compounding quantity of barium sulfate was 10 mass% in the kneading chip. This kneaded chip was melt-spun with an extruder-type spinning machine and drawn to obtain a monofilament containing a 560 dtex / 1f radiopaque agent.

Example 8
The polylactic acid chip used in Example 4 was melt-spun with an extruder-type spinning machine and stretched, and the resulting filament was mechanically crimped and then cut to obtain a single yarn fineness of 2.2 dtex, fiber A colorless staple fiber having a length of 51 mm was obtained. This staple fiber was spun to obtain 20th colorless spun yarn.
The colorless spun yarn obtained as described above was dyed with a disperse dye using a pressurized high-temperature dyeing machine to obtain a dyed yarn dyed pink.
Using a ring twisting machine, a fiber bundle in which eight colorless spun yarns were aligned was subjected to a lower twist at a Z twist of 60 times / m (Z-60) to obtain a colorless twisted yarn. On the other hand, a fiber bundle in which eight dyed yarns were arranged together was used as a twisted yarn dyed by applying a lower twist at a Z twist of 60 times / m (Z-60) using a ring twisting machine. Seven colorless twisted yarns and one dyed twisted yarn were bundled and subjected to top twisting at 150 times / m (S-150) using a ring twisting machine to obtain various twisted yarns. The various plied yarns were heat-treated at 165 ° C. for 1 minute to obtain the modeling material of Example 8 having a wire diameter of 1.75 mm. In the obtained modeling material, the constituent fibers were melted and fixed by thermal bonding by heat treatment.

When the winding material evaluation (bobbin winding property) and the 3D printer evaluation test (3D printer output) were performed using the modeling materials obtained in Examples 4 to 8, in any material, in the winding evaluation Can be wound up flexibly and neatly, and in 3D printer output, it is possible to output neatly and have a glossy appearance and have various shaped products. Further, even in the operation of feeding the modeling material into the 3D printer, the feeding operation has been performed satisfactorily without any problem in the feeding device.

Claims (6)

It is a modeling material used for the hot melt lamination method 3D printer, and its form is a continuous thread-like form in which a plurality of thermoplastic synthetic fibers are converged,
A modeling material, wherein at least some of the plurality of thermoplastic synthetic fibers contain a functional additive. The modeling material according to claim 1, wherein the functional additive is a colorant. The modeling material according to claim 1 or 2, wherein two or more bundles of thermoplastic synthetic fibers are bundled to form a single continuous thread-like form. The bundle of thermoplastic synthetic fibers composed of a plurality of bundles is bundled by twisting two or more bundles to form a single continuous thread-like form, according to any one of claims 1 to 3. Modeling material. The modeling material according to claim 1, wherein the bundle of a plurality of thermoplastic synthetic fibers has a twist. The molding material according to any one of claims 1 to 5, wherein the thermoplastic synthetic fibers are converged by heat fusion.