Filament for three-dimensional modeling and modeled object using the same

Abstract

To provide a filament for three-dimensional modeling, which enables high-speed modeling of an object with excellent flexibility.SOLUTION: There is provided a filament for three-dimensional modeling, comprising an ethylene-propylene random copolymer (A). The ethylene-propylene random copolymer (A) includes an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2). An ethylene content (wt%) in the ethylene-propylene random copolymer (A2) is 5 times or more an ethylene content (wt%) in the ethylene-propylene random copolymer (A1). A total content of ethylene derived from the ethylene-propylene random copolymer (A) is 6 to 11 wt%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a filament for three-dimensional modeling containing an ethylene-propylene random copolymer, and a modeled object using the same. [Background technology]

[0002] Conventionally, 3D modeling using a 3D printer has been used to model thermoplastic resins using the fused deposition modeling method. Compared to injection molding, in which molten thermoplastic resin is injected into a mold and cooled to solidify to obtain a molded product, 3D modeling offers a greater degree of freedom in modeling and is useful for creating objects with a variety of shapes, making it attractive for a variety of applications, including medical use.

[0003] In this type of three-dimensional modeling, ABS resin (acrylonitrile-butadiene-styrene copolymer) and PLA resin (polylactic acid resin) are widely used as modeling materials, and in recent years, three-dimensional modeling filaments made from polypropylene-based resins have been proposed because they have the advantages of having less odor than ABS resin or PLA resin, being more chemically resistant, and producing more flexible models.

[0004] For example, a strand (filament for three-dimensional modeling) made of a polypropylene resin composition whose melt flow rate, crystallization peak temperature, and heat of fusion are defined within specific ranges has been proposed (see, for example, Patent Document 1).

[0005] In addition, a filament for a three-dimensional printer (filament for three-dimensional modeling) has been proposed, which is made of a propylene-based copolymer having a structural unit derived from propylene and a structural unit derived from an α-olefin other than propylene, and whose intrinsic viscosity, weight-average molecular weight, melting point, and density are specified within specific ranges (see, for example, Patent Document 2).

[0006] Furthermore, a consumable filament (filament for three-dimensional modeling) containing a propylene-ethylene copolymer in which the content of ethylene-derived units, the melt flow rate, and the content of xylene-solubles are specified within specific ranges has been proposed (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 2017-197627 [Patent Document 2] Japanese Patent Application Publication No. 2018-158451 [Patent Document 3] Special Publication No. 2019-513913 Summary of the Invention [Problem to be solved by the invention]

[0008] It is difficult to say that the filaments for three-dimensional modeling described in Patent Documents 1 to 3 provide products that have sufficient flexibility, and there is a risk of defective modeling occurring when modeling is performed at a high modeling speed.

[0009] The present invention has been made in consideration of the above circumstances, and aims to provide a filament for three-dimensional modeling that enables highly flexible objects to be formed at high speed, and a modeled object using the same. [Means for solving the problem]

[0010] The characteristic configuration of the filament for three-dimensional modeling according to the present invention to solve the above problems is as follows: A filament for three-dimensional modeling containing an ethylene-propylene random copolymer (A), the ethylene-propylene random copolymer (A) contains an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2), the ethylene content (wt%) in the ethylene-propylene random copolymer (A2) is 5 times or more the ethylene content (wt%) in the ethylene-propylene random copolymer (A1); The total content of ethylene derived from the ethylene-propylene random copolymer (A) is 6 to 11% by weight.

[0011] According to this three-dimensional modeling filament, the ethylene-propylene random copolymer (A) contains an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2). The ethylene content (wt%) of the ethylene-propylene random copolymer (A2) is selected to be at least five times the ethylene content (wt%) of the ethylene-propylene random copolymer (A1). This results in two copolymers with different melting points and fluidity due to the ethylene content. While propylene homopolymers (homopolymers) are crystalline, the greater the ethylene content of a propylene-ethylene copolymer, the greater its amorphousness, which leads to a decrease in melting point and ultimately to the disappearance of the melting point. Furthermore, the greater the amorphousness, the less fluid the resin becomes when heated, resulting in a softer resin. Furthermore, since the ethylene content (x) in the ethylene-propylene random copolymer (A1) and the ethylene content (y) in the ethylene-propylene random copolymer (A2) differ by 5 times or more (y≧5x), these two copolymers have melting points and fluidities corresponding to their respective ethylene contents. Furthermore, since the total ethylene content derived from the ethylene-propylene random copolymer (A) in the three-dimensional printing filament is 6 to 11 wt %, the fluidities of the two copolymers fall within an appropriate range. Due to the difference in fluidity between the two copolymers, the three-dimensional printing filament containing the ethylene-propylene random copolymer (A) as a mixture thereof melts and solidifies appropriately, and the objects manufactured using the filament are appropriately soft. This allows the three-dimensional printing filament to rapidly produce objects with excellent flexibility.

[0012] In the filament for three-dimensional modeling according to the present invention, The MFR value measured in accordance with JIS K7210 under conditions of 230°C and a load of 2.16 kg is preferably 30 to 60 g / 10 min.

[0013] According to the filament for three-dimensional printing having the above-described MFR value, the filament for three-dimensional printing has a flowability suitable for high-speed printing of an object with excellent flexibility, thereby enabling high-speed printing of an object with excellent flexibility.

[0014] In the filament for three-dimensional modeling according to the present invention, the ethylene-propylene random copolymer (A1) has an MFR value of 10 to 60 g / 10 min, as measured in accordance with JIS K7210 under conditions of 230°C and a load of 2.16 kg; The MFR value of the ethylene-propylene random copolymer (A2) is preferably 1 to 60 g / 10 min.

[0015] According to the three-dimensional printing filament of this configuration, by setting the MFR values ​​of the ethylene-propylene random copolymer (A1) and the ethylene-propylene random copolymer (A2) within the above ranges, these two copolymers each have a specific fluidity, and the three-dimensional printing filament containing these two copolymers has a fluidity more suitable for high-speed printing of a highly flexible object. As a result, the three-dimensional printing filament enables high-speed printing of a highly flexible object.

[0016] In the filament for three-dimensional modeling according to the present invention, It is preferred that the composition further contains a polypropylene homopolymer.

[0017] The three-dimensional modeling filament of this configuration further contains polypropylene homopolymer, which means that it contains three components with different crystallinity: ethylene-propylene random copolymer (A1), ethylene-propylene random copolymer (A2), and polypropylene homopolymer, thereby expanding the range of crystallinity adjustment. This allows for detailed adjustment of crystallinity, which correlates with melting point and fluidity, and makes it possible to use the three-dimensional modeling filament to rapidly create highly accurate, flexible models.

[0018] To solve the above problems, a shaped object according to the present invention comprises: The reason is that the filament for three-dimensional modeling is used.

[0019] According to the shaped object of this configuration, since the shaped object is made using the filament for three-dimensional modeling described above, the shaped object has excellent flexibility and can be formed at high speed. DETAILED DESCRIPTION OF THE INVENTION

[0020] The filament for three-dimensional modeling of the present invention and a modeled object using the same will be described below.

[0021] <3D modeling filament> The filament for three-dimensional shaping of this embodiment is a filament for three-dimensional shaping containing an ethylene-propylene random copolymer (A). The ethylene-propylene random copolymer (A) contains an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2), and the ethylene content (wt%) in the ethylene-propylene random copolymer (A2) is 5 times or more the ethylene content (wt%) in the ethylene-propylene random copolymer (A1).

[0022] In this specification, the "ethylene content in the ethylene-propylene random copolymer (A1)" refers to the total weight of ethylene units (-CH2-CH2-) contained in the ethylene-propylene random copolymer (A1) expressed as a percentage of the weight of the entire ethylene-propylene random copolymer (A1) (all constituent units), and is expressed in wt%. The "ethylene content in the ethylene-propylene random copolymer (A2)" has the same meaning. Furthermore, the "total ethylene content derived from the ethylene-propylene random copolymer (A)" refers to the total weight of ethylene units (-CH2-CH2-) contained in all ethylene-propylene random copolymers contained in the ethylene-propylene random copolymer (A) expressed as a percentage of the total weight of the three-dimensional modeling filament, and is expressed in wt%. The ethylene content (wt%) of each ethylene-propylene random copolymer can be obtained by determining the weight ratio of ethylene units (-CH2-CH2-) to propylene units (-CH(CH3)-CH2-) in the ethylene-propylene random copolymer using infrared total reflection absorption spectroscopy, and then calculating the percentage of the weight of the ethylene units relative to the total weight of the ethylene units and propylene units from this weight ratio. The total ethylene content (wt%) derived from the ethylene-propylene random copolymer (A) can be obtained by calculating the total weight of ethylene contained in the three-dimensional modeling filament from the blending amount (weight) of each ethylene-propylene random copolymer contained in the three-dimensional modeling filament and the ethylene content (wt%) in each ethylene-propylene random copolymer, and then calculating the percentage of the total weight of ethylene relative to the total weight of the three-dimensional modeling filament. In this specification, "wt%" may be replaced with "mass%."

[0023] According to this filament for three-dimensional modeling, the ethylene-propylene random copolymer (A) contains an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2). The ethylene content (wt%) in the ethylene-propylene random copolymer (A2) is selected to be at least five times the ethylene content (wt%) in the ethylene-propylene random copolymer (A1). This results in two copolymers with different melting points and fluidities due to the ethylene content. While propylene homopolymers (homopolymers) are crystalline, the greater the ethylene content of a propylene-ethylene copolymer, the greater its amorphousness, which in turn lowers its melting point and ultimately eliminates it altogether. Furthermore, the greater the amorphousness, the lower the fluidity upon heating, resulting in a softer resin. Furthermore, since the ethylene content (x) in the ethylene-propylene random copolymer (A1) and the ethylene content (y) in the ethylene-propylene random copolymer (A2) differ by 5 times or more (y≧5x), these two copolymers have melting points and fluidities corresponding to their respective ethylene contents. Furthermore, since the total ethylene content derived from the ethylene-propylene random copolymer (A) in the three-dimensional printing filament is 6 to 11 wt %, the fluidities of the two copolymers fall within an appropriate range. Due to the difference in fluidity between the two copolymers, the three-dimensional printing filament containing the ethylene-propylene random copolymer (A) as a mixture thereof melts and solidifies appropriately, and the objects manufactured using the filament are appropriately soft. This allows the three-dimensional printing filament to rapidly produce objects with excellent flexibility.

[0024] As described above, the filament for three-dimensional modeling has a total ethylene content derived from the ethylene-propylene random copolymer (A) of 6 to 11 wt%, preferably 7 to 10 wt%. The total ethylene content derived from the copolymer (A) correlates with the flexibility of the resulting shaped object, and a total ethylene content of 6 wt% or more can increase the flexibility of the shaped object, while a total ethylene content of 11 wt% or less can prevent the flexibility of the shaped object from being excessively increased.

[0025] Hereinafter, the ethylene-propylene random copolymer (A), the ethylene-propylene random copolymer (A1), and the ethylene-propylene random copolymer (A2) will also be referred to as "copolymer (A)," "copolymer (A1)," and "copolymer (A2)," respectively.

[0026] <Ethylene-propylene random copolymer (A)> Copolymer (A) includes copolymer (A1) and copolymer (A2). Each of these copolymers is obtained by polymerizing the raw materials ethylene and propylene using a Ziegler-Natta catalyst, a metallocene catalyst, or the like. Polymerization methods for each copolymer include polymerizing ethylene and propylene in an inert solvent such as hexane, heptane, toluene, or xylene; polymerizing them in liquid ethylene and propylene; adding a catalyst to gaseous ethylene and propylene and polymerizing them in the gas phase; or a combination of these polymerization methods.

[0027] The total ethylene content in copolymer (A) is preferably 6 to 11% by weight. When the total ethylene content in copolymer (A) is 6% by weight or more, the flexibility of the shaped article can be increased, and when it is 11% by weight or less, the flexibility of the shaped article can be prevented from being excessively increased.

[0028] <Ethylene-Propylene Random Copolymers (A1) and (A2)> The copolymer (A1) and the copolymer (A2) contained in the copolymer (A) are configured so that the ethylene content (wt%) in the copolymer (A2) is 5 times or more the ethylene content (wt%) in the copolymer (A1).

[0029] The copolymer (A1) preferably has an ethylene content of 0.1 to 4% by weight. When the ethylene content in the copolymer (A1) is 0.1% by weight or more, the time required for the copolymer (A) containing this copolymer (A1), and therefore the filament for three-dimensional modeling, to melt is shortened, and the occurrence of defective discharge on the surface of a modeled article modeled at high speed can be suppressed. When the ethylene content in the copolymer (A1) is 4% by weight or less, the copolymer (A) containing this copolymer (A1), and therefore the filament for three-dimensional modeling, can be prevented from becoming difficult to solidify after melting, and the occurrence of defective modeling in a modeled article modeled at high speed, such as stringiness and deformation (twisting, etc.), can be suppressed.

[0030] The content of copolymer (A1) in copolymer (A) is preferably 15 to 65 wt %, more preferably 20 to 60 wt %. By setting the content of copolymer (A1) within the above range, the content becomes more suitable for high-speed molding of shaped articles with excellent flexibility.

[0031] Copolymer (A1) can be a commercially available product, such as SunAllomer (registered trademark) PM921M (manufactured by SunAllomer Co., Ltd.) or SunAllomer (registered trademark) PMA20V (manufactured by SunAllomer Co., Ltd.) Copolymer (A1) can be used either alone or as a mixture of two or more types.

[0032] Copolymer (A2) has an ethylene content (wt%) that is at least 5 times the ethylene content (wt%) in copolymer (A1) on a weight basis. Copolymer (A2) preferably has an ethylene content of 0.5 to 20 wt%. Having an ethylene content of 0.5 wt% or more in copolymer (A2) shortens the time required for copolymer (A) containing copolymer (A2), and thus the filament for three-dimensional printing, to melt, and can suppress discharge defects on the surface of a shaped product shaped at high speed. Having an ethylene content of 20 wt% or less in copolymer (A2) can suppress copolymer (A) containing copolymer (A2), and thus the filament for three-dimensional printing, from becoming difficult to solidify after melting, thereby suppressing molding defects such as stringiness and deformation (twisting, etc.) in a shaped product shaped at high speed.

[0033] The content of copolymer (A2) in copolymer (A) is preferably 35 to 85 wt %, more preferably 40 to 80 wt %. By setting the content of copolymer (A2) within the above range, the content becomes more suitable for high-speed molding of shaped articles with excellent flexibility.

[0034] Copolymer (A2) may be a commercially available product, such as Vistamaxx Performance Polymer 6102 (manufactured by ExxonMobil), Vistamaxx Performance Polymer 6502 (manufactured by ExxonMobil), etc. Copolymer (A2) may be used either alone or as a mixture of two or more types.

[0035] The blending ratio (A1 / A2) of copolymer (A1) and copolymer (A2) is preferably set to a weight ratio of 15 / 85 to 65 / 35, more preferably 25 / 75 to 55 / 45, and even more preferably 25 / 75 to 45 / 55. By setting the blending ratio (A1 / A2) to 15 / 85 or more, the blending ratio (A1 / A2) becomes appropriately large, which can prevent copolymer (A) containing these copolymers (A1) and (A2) from becoming difficult to solidify upon heating, thereby suppressing the occurrence of molding defects such as stringiness and twisting in objects molded at high speed. By setting the blending ratio (A1 / A2) to 65 / 35 or less, the blending ratio (A1 / A2) becomes appropriately small, which shortens the time required for copolymer (A) containing these copolymers (A1) and (A2) to melt upon heating, thereby suppressing the occurrence of ejection defects on the surface of objects molded at high speed.

[0036] The total content of copolymer (A1) and copolymer (A2) in copolymer (A) is preferably 95% by weight or more, more preferably 99% by weight or more, and may be 100% by weight.

[0037] The content of the copolymer (A) in the filament for three-dimensional modeling is preferably 90% by weight or more, more preferably 95% by weight or more, and may be 100% by weight.

[0038] The MFR value of copolymer (A1) measured in accordance with JIS K7210 at 230°C under a load of 2.16 kg (hereinafter simply referred to as "MFR value") is preferably 10 to 60 g / 10 min, more preferably 25 to 45 g / 10 min. By setting the MFR value of copolymer (A1) within the above range, its fluidity becomes more suitable for high-speed molding of shaped objects with excellent flexibility.

[0039] The MFR value of the copolymer (A2) is preferably 1 to 60 g / 10 min, more preferably 3 to 45 g / 10 min. By setting the MFR value of the copolymer (A2) within the above range, its fluidity becomes more suitable for high-speed molding of shaped objects with excellent flexibility.

[0040] Furthermore, by setting the MFR values ​​of the copolymers (A1) and (A2) within the above ranges, the two copolymers (A1) and (A2) each have a specific fluidity, and the three-dimensional modeling filament containing the two copolymers (A1) and (A2) has a fluidity more suitable for high-speed modeling of a flexible object. As a result, the three-dimensional modeling filament enables high-speed modeling of a flexible object.

[0041] <Optional ingredients> The filament for three-dimensional fabrication preferably contains only the above-mentioned copolymer (A). However, the filament for three-dimensional fabrication may contain optional components such as resin components other than the copolymer (A), heat stabilizers, ultraviolet absorbers, light stabilizers, antibacterial agents, and processing aids, as long as the object of the present invention is not impaired.

[0042] <Resin Components Other Than Copolymer (A)> Examples of resin components other than copolymer (A) include polypropylene homopolymer and propylene-ethylene block copolymer. Of these, the filament for three-dimensional printing preferably further contains a polypropylene homopolymer in addition to the copolymer (A). Polypropylene homopolymer is a homopolymer of propylene. By further containing a polypropylene homopolymer, the filament for three-dimensional printing contains three components with different crystallinity: copolymer (A1), copolymer (A2), and polypropylene homopolymer, thereby broadening the range of crystallinity adjustment. This allows for precise adjustment of the crystallinity, which is correlated with the melting point and fluidity. Therefore, the filament for three-dimensional printing can be used to rapidly print highly accurate, flexible objects.

[0043] The content of the polypropylene homopolymer in the filament for three-dimensional modeling is preferably 1 to 10 wt %, more preferably 1 to 5 wt %. By setting the content of the polypropylene homopolymer within this range, the filament for three-dimensional modeling is imparted with appropriate crystallinity derived from the polypropylene homopolymer, thereby providing the filament with fluidity more suitable for high-speed modeling of highly flexible objects.

[0044] <Heat stabilizer> The thermal stabilizer is used to improve thermal stability during the production of the filament for three-dimensional modeling, during the modeling of a modeled object, and the like.

[0045] As the heat stabilizer, a phosphorus-based stabilizer and / or a hindered phenol-based antioxidant are preferred, and a combination of these is more preferred.

[0046] The amount of the phosphorus-based stabilizer and / or hindered phenol-based antioxidant in the filament for three-dimensional modeling is not particularly limited and can be appropriately set. From the viewpoint of reliably obtaining the effect of improving thermal stability and not affecting the amounts of the copolymers (A1) and (A2), the content of the phosphorus-based stabilizer and / or hindered phenol-based antioxidant in the filament for three-dimensional modeling is preferably 0.01 to 1 wt%, more preferably 0.01 to 0.6 wt%.

[0047] Examples of phosphorus-based stabilizers include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid, esters of these acids, and tertiary phosphines.

[0048] Examples of phosphorous esters (phosphite compounds) include triphenyl phosphite, tris(nonylphenyl)phosphite, tridecyl phosphite, distearyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis[2,4-bis(1-methyl-1-phenylethyl)phenyl]pentaerythritol diphosphite, phenyl bisphenol A pentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, and dicyclohexyl pentaerythritol diphosphite.

[0049] In addition to the above, the phosphorous ester (phosphite compound) may also be one which reacts with a dihydric phenol and has a cyclic structure, such as 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2,4-di-tert-butylphenyl)phosphite, 2,2'-methylenebis(4,6-di-tert-butylphenyl)(2-tert-butyl-4-methylphenyl)phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octylphosphite, and the like.

[0050] Examples of the phosphoric acid ester (phosphate compound) include triphenyl phosphate and trimethyl phosphate.

[0051] Examples of phosphonite esters (phosphonite compounds) include tetrakis(2,4-di-tert-butylphenyl)-biphenylene diphosphonite, bis(2,4-di-tert-butylphenyl)-phenylphosphonite, etc. Phosphonite compounds are preferred from the viewpoint that they can be used in combination with the above-mentioned phosphite compounds having an aryl group substituted with two or more alkyl groups.

[0052] Examples of phosphonate esters (phosphonate compounds) include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

[0053] Tertiary phosphines include triphenylphosphine and the like.

[0054] Among the above phosphorus-based stabilizers, phosphonite compounds or phosphite compounds represented by the following general formula (1) are preferred.

[0055] [ka]

[0056] In formula (1), R and R' represent an alkyl group having 6 to 30 carbon atoms or an aryl group having 6 to 30 carbon atoms, and may be the same or different.

[0057] As mentioned above, the phosphonite compound is preferably tetrakis(2,4-di-tert-butylphenyl)-biphenylene diphosphonite.

[0058] Of the phosphite compounds represented by the above formula (1), distearyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, and bis[2,4-bis(1-methyl-1-phenylethyl)phenyl]pentaerythritol diphosphite are preferred.

[0059] Examples of hindered phenol antioxidants include tetrakis[methylene-3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionate]methane, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 3,9-bis[2-{3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy}-1,1-dimethylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane.

[0060] The filament for three-dimensional shaping may contain other heat stabilizers besides the phosphorus-based stabilizer and / or the hindered phenol-based antioxidant.

[0061] Other examples of the heat stabilizer include lactone stabilizers such as the reaction product of 3-hydroxy-5,7-di-tert-butyl-furan-2-one and o-xylene (see Japanese Patent Application Laid-Open No. 7-233160).

[0062] Examples of lactone stabilizers include Irganox HP-136 (registered trademark, manufactured by CIBA SPECIALTY CHEMICALS).

[0063] Examples of heat stabilizers that are mixtures of a lactone-based stabilizer, a phosphite compound as a phosphorus-based stabilizer, and a hindered phenol-based antioxidant include Irganox HP-2921 (registered trademark, manufactured by CIBA SPECIALTY CHEMICALS).

[0064] The content of the lactone-based stabilizer in the filament for three-dimensional modeling is preferably 0.0005 to 0.05% by weight, and more preferably 0.001 to 0.03% by weight.

[0065] Other heat stabilizers include sulfur-containing stabilizers such as pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(3-laurylthiopropionate), glycerol-3-stearylthiopropionate, etc. The heat stabilizers can be used alone or as a mixture of two or more.

[0066] The blending amount of the heat stabilizer in the filament for three-dimensional modeling is preferably 0.0005 to 0.1% by weight, more preferably 0.001 to 0.08% by weight, and even more preferably 0.001 to 0.05% by weight.

[0067] <UV absorber> The ultraviolet absorber is used to suppress deterioration of the filament for three-dimensional modeling and to improve weather resistance.

[0068] Examples of benzophenone-based ultraviolet absorbers include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benzyloxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydridolate benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2',4,4'-tetrahydroxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxy-5-sodium sulfoxybenzophenone, bis(5-benzoyl-4-hydroxy-2-methoxyphenyl)methane, 2-hydroxy-4-n-dodecyloxybenzophenone, and 2-hydroxy-4-methoxy-2'-carboxybenzophenone.

[0069] Benzotriazole-based UV absorbers include 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)benzotriazole, 2-(2-hydroxy-3,5-dicumylphenyl)phenylbenzotriazole, 2-(2-hydroxy-3-tert-butyl-5-methylphenyl)-5-chlorobenzotriazole, 2,2'-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-(2H-benzotriazol-2-yl)phenol], 2-(2-hydroxy-3,5-di-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole, and 2-(2-hydroxy-3,5-di-tert -amylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-butylphenyl)benzotriazole, 2-(2-hydroxy-4-octoxyphenyl)benzotriazole, 2,2'-methylenebis(4-cumyl-6-benzotriazolephenyl), 2-[2-hydroxy-3-(3,4,5,6-tetrahydrophthalimidomethyl)-5-methylphenyl]benzotriazole, as well as polymers having a 2-hydroxyphenyl-2H-benzotriazole skeleton such as copolymers of 2-(2'-hydroxy-5-methacryloxyethylphenyl)-2H-benzotriazole and vinyl monomers, and copolymers of 2-(2'-hydroxy-5-acryloxyethylphenyl)-2H-benzotriazole and vinyl monomers.

[0070] Examples of hydroxyphenyltriazine-based ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-methyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-ethyloxyphenol, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-propyloxyphenol, and 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-butyloxyphenol. Further examples include compounds in which the phenyl group of the above-mentioned compounds is replaced with a 2,4-dimethylphenyl group, such as 2-(4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl)-5-hexyloxyphenol.

[0071] Examples of cyclic iminoester-based ultraviolet absorbers include 2,2'-p-phenylenebis(3,1-benzoxazin-4-one), 2,2'-(4,4'-diphenylene)bis(3,1-benzoxazin-4-one), and 2,2'-(2,6-naphthalene)bis(3,1-benzoxazin-4-one).

[0072] Examples of cyanoacrylate ultraviolet absorbers include 1,3-bis-[(2'-cyano-3',3'-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane and 1,3-bis-[(2-cyano-3,3-diphenylacryloyl)oxy]benzene.

[0073] The ultraviolet absorber may be a radically polymerizable monomer compound, or a polymeric ultraviolet absorber that is a copolymer of an ultraviolet absorbing monomer and / or a photostable monomer having a hindered amine structure with a monomer such as alkyl (meth)acrylate. Examples of the ultraviolet absorbing monomer include compounds that contain a benzotriazole skeleton, a benzophenone skeleton, a triazine skeleton, a cyclic imino ester skeleton, or a cyanoacrylate skeleton in the ester substituent of a (meth)acrylic acid ester.

[0074] Among the above compounds, from the viewpoint of ultraviolet absorbing performance, benzotriazole-based ultraviolet absorbers and hydroxyphenyltriazine-based ultraviolet absorbers are preferred, and from the viewpoint of heat resistance and hue (transparency), cyclic iminoester-based ultraviolet absorbers and cyanoacrylate-based ultraviolet absorbers are preferred. The ultraviolet absorbers can be used alone or as a mixture of two or more kinds.

[0075] The content of the ultraviolet absorber in the filament for three-dimensional fabrication is preferably 0.01 to 2% by weight, more preferably 0.02 to 2% by weight, even more preferably 0.03 to 1% by weight, and even more preferably 0.05 to 0.5% by weight.

[0076] <Light stabilizer> The light stabilizer is used to suppress deterioration of the three-dimensional modeling filament due to discoloration (yellowing) in dark places.

[0077] Examples of light stabilizers include hindered amine light stabilizers (HALS), which are compounds represented by the following general formulas (2) to (5) and combinations of two or more of these compounds.

[0078] [ka]

[0079] In formulas (2) to (5), R1 to R5 each independently represent a hydrogen atom, an ether group, an ester group, an amine group, an amide group, an alkyl group, an alkenyl group, an alkynyl group, an aralkyl group, a cycloalkyl group, or an aryl group, and these groups may be substituted with an alcohol group, a ketone group, an imine group, a siloxane group, an ether group, a carboxy group, an aldehyde group, an ester group, an amide group, an imide group, an amine group, a nitrile group, a urethane group, or a combination thereof, or may be an anhydride.

[0080] As the hindered amine light stabilizer, a compound derived from a substituted piperidine compound is preferred, and a compound derived from an alkyl-substituted piperidyl, piperidinyl or piperazinone compound, or an alkoxy-substituted piperidinyl compound is more preferred.

[0081] Hindered amine light stabilizers include 2,2,6,6-tetramethyl-4-piperidone, 2,2,6,6-tetramethyl-4-piperidinol, bis-(1,2,2,6,6-pentamethylpiperidyl)-(3',5'-di-tert-butyl-4'-hydroxybenzyl)butylmalonate, di-(2,2,6,6-tetramethyl-4-piperidyl)sebacate, and N-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-piperidinol. Oligomers of ethanol and succinic acid, oligomers of cyanuric acid and N,N-di(2,2,6,6-tetramethyl-4-piperidyl)-hexamethylenediamine, bis-(2,2,6,6-tetramethyl-4-piperidinyl) succinate, bis-(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate, bis-(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, tetrakis-(2,2,6,6 -tetramethyl-4-piperidyl)-1,2,3,4-butane-tetracarboxylate, N,N'-bis-(2,2,6,6-tetramethyl-4-piperidyl)-hexane-1,6-diamine, N-butyl-2,2,6,6-tetramethyl-4-piperidinamine, 2,2'-[(2,2,6,6-tetramethylpiperidinyl)-imino]-bis-[ethanol], poly((6-morpholine-S-triazine-2,4-diyl)(2,2,6, 6-tetramethyl-4-piperidinyl)-iminohexamethylene-(2,2,6,6-tetramethyl-4-piperidinyl)-imino), 5-(2,2,6,6-tetramethyl-4-piperidinyl)-2-cyclo-undecyl-oxazole, 1,1´-(1,2-ethane-di-yl)-bis-(3,3´,5,5´-tetramethylpiperazinone), 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5] Decane-2,4-dione, polymethylpropyl-3-oxy-[4(2,2,6,6-tetramethyl)-piperidinyl]siloxane, 1,2,3,4-butane-tetracarboxylic acid-1,2,3-tris(1,2,2,6,6-pentamethyl-4-piperidinyl)-4-tridecyl ester, copolymer of α-methylstyrene-N-(2,2,6,6-tetramethyl-4-piperidinyl)maleimide and N-stearylmaleimide, 1,2,3,4-butane-tetracarboxylic acid and β,β,β',β'-tetramethyl-2,4,8,10-tetraoctanoic acid Polymers of oxaspiro[5.5]undecane-3,9-diethanol and 1,2,2,6,6-pentamethyl-4-piperidinyl ester, β,β,β´,β´-tetramethyl-polymers of 2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diethanol, 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinyl ester, and polymers of D-glucitol and 1,3:2,4-bis-o-(2,2,6,6-tetramethyl-4-piperidinylidene)-7-oxa-3,20-diazadispiro[5.5]undecane-3,9-diethanol. Oligomers of 1,11,2]-heneicosan-21-one with 2,2,4,4-tetramethyl-20-(oxiranylmethyl), esters of propanedioic acid with [(4-methoxyphenyl)methylene]-bis(1,2,2,6,6-pentamethyl-4-piperidinyl), N,N'-1,6-hexanediylbis[N-(2,2,6,6-tetramethyl-4-piperidinyl)formamide], 1,3,5-triazine-2,4,6-triamine, N,N'''-[1,2-ethanediylbis[[[4,6-bis[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)] methyl-4-piperidinyl)amino]-1,3,5-triazin-2-yl]imino]-3,1-propanediyl]]-bis[N',N''-dibutyl-N',N''-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)], poly[[6-[(1,1,3,3-tetramethylbutyl)amino]-1,3,5-triazine-2,4-diyl][(2,2,6,6-tetramethyl-4-piperidinyl)-imino]-1,6-hexanediyl[(2,2,6,6-tetramethyl-4-piperidinyl)imino]], 1,5-dioxaspiro(5.5) Ester of undecane 3,3-dicarboxylic acid and bis(2,2,6,6-tetramethyl-4-piperidinyl), ester of 1,5-dioxaspiro[5.5]undecane 3,3-dicarboxylic acid and bis(1,2,2,6,6-pentamethyl-4-piperidinyl), N-2,2,6,6-tetramethyl-4-piperidinyl-N-amino-oxamide, 4-acryloyloxy-1,2,2,6,6-pentamethyl-4-piperidine, 1,5,8,12-tetrakis[2',4'-bis(1',2',2',6',6'-pentamethyl-4''-piperidinyl(butyl)amino)-1',3',5'-triazin-6'-yl]-1,5 ,8,12-tetraazadodecane, 3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)-pyrrolidine-2,5-dione, 1,1'-(1,2-ethane-diyl)-bis-(3,3',5,5'-tetramethylpiperazinone), 1,1'1''-(1,3,5-triazine-2,4,6-triyltris((cyclohexylimino)-2,1-ethanediyl))tris(3,3,5,5-tetramethylpiperazinone), 1,1',1''-(1,3,5-triazine-2,4,6-triyltris((cyclohexylimino)-2,1-ethanediyl))tris(3,3,4,5-tetramethylpiperazinone).

[0082] The content of the hindered amine light stabilizer in the filament for three-dimensional shaping is preferably 0.01 to 5 wt%, more preferably 0.05 to 3 wt%, and even more preferably 0.1 to 1 wt%. The hindered amine light stabilizer can be used alone or as a mixture of two or more kinds.

[0083] <Antibacterial agent> As the antibacterial agent, preferred are inorganic antibacterial agents such as antibacterial metals such as zinc oxide, silver, copper, and zinc, or those in which these antibacterial metals are supported on crystalline aluminosilicate, amorphous aluminosilicate, silica gel, activated alumina, diatomaceous earth, activated carbon, zirconium phosphate, hydroxyapatite, magnesium oxide, magnesium perchlorate, glass, etc. As the inorganic antibacterial agent, zinc oxide is preferred.

[0084] The zinc oxide used as the inorganic antibacterial agent may be a commercially available product, or may be zinc oxide obtained by heating metallic zinc to vaporize it and burning it in air, or zinc oxide obtained by heating zinc sulfate or zinc nitrate. Zinc oxide may be used in various shapes, such as fiber, plate, particle, tetrapod, etc. Zinc oxide may be surface-treated with silicon oxide, silicone oil, organosilicon compound, organotitanium compound, etc.

[0085] Examples of commercially available zinc oxide include "type 1 zinc oxide," "type 2 zinc oxide," and "type 3 zinc oxide" classified by JIS K-1410, official zinc oxide specified in the Japanese Pharmacopoeia, and anisotropic (columnar, plate-like, or tetrapod-like) zinc oxide (shape-anisotropic zinc oxide) prepared via a hydrothermal synthesis process. Particulate zinc oxide having an average particle size of 50 to 200 nm, indicated by the particle size at which the cumulative weight distribution is 50%, is preferred, and particulate zinc oxide having an average particle size of 100 to 150 nm is particularly preferred.

[0086] The content of the antibacterial agent in the filament for three-dimensional modeling is preferably 0.01 to 1% by weight, more preferably 0.05 to 0.5% by weight, and even more preferably 0.1 to 0.3% by weight.

[0087] <Processing aids> The processing aid is not particularly limited, but examples thereof include metal salts of long-chain fatty acids represented by the following general formula (6). M(OH) y (R-COO) x ···(6)

[0088] In formula (6), R is an alkyl group or alkenyl group having 6 to 40 carbon atoms, M is a metal element, x+y is the valence of M (x+y=M), and y is an integer from 0 to M-1.

[0089] The metal element M is preferably a metal element selected from aluminum, zinc, calcium, magnesium, lithium, and barium, and more preferably zinc or aluminum.

[0090] Examples of long-chain fatty acids include caproic acid, capric acid, lauric acid, palmitic acid, stearic acid, behenic acid, lignoceric acid, montanic acid, oleic acid, and linoleic acid, with stearic acid, behenic acid, and montanic acid being preferred, and stearic acid being more preferred.

[0091] Examples of long-chain fatty acid metal salts include zinc stearate, zinc 12-hydroxystearate, zinc laurate, zinc oleate, zinc 2-ethylhexanoate, aluminum tristearate, (dihydroxy)aluminum monostearate, (hydroxy)aluminum distearate, aluminum 12-hydroxystearate, aluminum laurate, aluminum oleate, and aluminum 2-ethylhexanoate, of which zinc stearate, aluminum tristearate, (dihydroxy)aluminum monostearate, or (hydroxy)aluminum distearate is preferred, and (hydroxy)aluminum distearate is more preferred.

[0092] The content of the processing aid in the filament for three-dimensional modeling is preferably 0.1 to 5 wt%, more preferably 1 to 4 wt%, and even more preferably 2 to 4 wt%. By setting the content of the processing aid within the above range, the effect of the processing aid can be fully exerted. The processing aid can be used alone or as a mixture of two or more kinds.

[0093] Optional components other than those mentioned above include dyes and pigments for coloring, antistatic agents, release agents, fillers, flame retardants, and the like.

[0094] <Method of manufacturing filaments for 3D modeling> The filament for three-dimensional modeling can be obtained, for example, by mixing copolymer (A) containing copolymer (A1) and copolymer (A2) with optional components, melt-kneading the resulting mixture (so-called dry blend) in an extruder or the like, pelletizing the resulting pellets, and then extruding the resulting pellets in the extruder. Alternatively, the filament can be obtained by extruding the mixture in the extruder without pelletizing. When liquid components are used as blending components, a so-called liquid injection device or liquid addition device can be used to supply the components to the extruder. The heating temperature for melt-kneading can usually be set in the range of 180 to 220°C.

[0095] <Characteristics of filaments for 3D modeling> The three-dimensional printing filament preferably has an MFR value of 30 to 60 g / 10 min, more preferably 35 to 60 g / 10 min, and even more preferably 45 to 60 g / 10 min, as measured in accordance with JIS K7210 at 230°C under a load of 2.16 kg. By setting the MFR value of the three-dimensional printing filament within the above range, the three-dimensional printing filament has a fluidity suitable for high-speed modeling of highly flexible objects. This allows the three-dimensional printing filament to rapidly model highly flexible objects. Specifically, an MFR value of 30 g / 10 min or more can further suppress discharge defects in the modeling device during modeling, facilitating high-speed modeling. An MFR value of 60 g / 10 min or less eliminates the need to unnecessarily increase the fluidity of the three-dimensional printing filament.

[0096] The flexibility of the three-dimensional printing filament is related to the flexibility of the resulting object. Therefore, it is preferable that the three-dimensional printing filament has a moderate flexibility, for example, a flexibility that allows a user to comfortably support the object. This flexibility is difficult to evaluate by evaluating a minute linear range, such as the modulus of elasticity. For example, one tip of a plate-shaped object fabricated using the three-dimensional printing filament is fixed to form a cantilever beam with a protruding length of 100 mm, a width of 10 mm, and a thickness of 4 mm. A load of 50 g is applied to the tip of this cantilever beam, and the deformation of the tip is measured. The resulting deformation can be used as an index of flexibility. If this deformation is too small, the object tends to be insufficiently flexible (i.e., too hard), while if the deformation is too large, the object tends to be excessively flexible (i.e., too soft). Considering this point, the deformation is preferably 10 to 50 mm, more preferably 10 to 40 mm. By setting the deformation within the above range, the three-dimensional printing filament has a moderate flexibility. The deformation amount is measured by the measurement method described below.

[0097] When modeling using the filament for three-dimensional printing, an appropriate feed amount of the filament is typically set as the feed length in the modeling device. If the filament cannot be fed into the modeling device, a discrepancy occurs between the set value of the feed length and the actual length (actual feed length), resulting in fluctuations in the discharge rate from the nozzle and, as a result, potential modeling defects. Therefore, the difference between the set value and the actual measured value of the feed length can be used as an indicator of the discharge rate, which is the rate of fluctuation in the discharge rate from the nozzle. The filament for three-dimensional printing preferably has a ratio (L2 / L1) of the set feed length (L1) to the actual feed length (L2) in the modeling device of 80% or greater. By setting the ratio (L2 / L1) within the above range, fluctuations in the discharge rate from the nozzle of the modeling device can be suppressed, thereby preventing modeling defects. The ratio (L2 / L1) is measured as the discharge rate using the measurement method described below.

[0098] <Modeling using 3D modeling filaments> Using the three-dimensional printing filament, a model can be produced as follows. Specifically, any modeling device capable of producing a model by extrusion lamination, including a melting section for melting the three-dimensional printing filament and a movable nozzle capable of discharging the melted three-dimensional printing filament in the melting section, can be used to melt the three-dimensional printing filament through the movable nozzle at a predetermined melt extrusion temperature to produce a model. The melt extrusion temperature can typically be set within a range of 200±60°C (140 to 260°C). A melt extrusion temperature of 140°C or higher can enhance the meltability of the three-dimensional printing filament in the melting section, thereby preventing deterioration of the appearance of the modeled product due to poor discharge from the movable nozzle. A melt extrusion temperature of 260°C or lower can prevent adverse effects on the modeled product, such as discoloration and burning, and the occurrence of poor stringiness.

[0099] <Sculpture> The object of the present embodiment is formed using the filament for three-dimensional printing of the present embodiment described above. Because the object is formed using the filament for three-dimensional printing of the present embodiment, the object has excellent flexibility and can be formed at high speed.

[0100] The present invention will be further described below with reference to examples, but the present invention is not limited to these examples. [Example]

[0101] Filaments for three-dimensional fabrication having the characteristic configuration of the present invention (Examples 1 to 12) were produced, and various measurements and evaluations were performed. For comparison, filaments for three-dimensional fabrication not having the characteristic configuration of the present invention (Comparative Examples 1 to 10) were produced, and similar measurements and evaluations were performed. The results are shown in Tables 1 to 5.

[0102] [Raw materials used] Ethylene-propylene random copolymer (A1) As the copolymer (A1), copolymers (A1-1) and (A1-2) obtained as follows were used.

[0103] (A1-1) Propylene and ethylene were copolymerized in the gas phase using a Ziegler-Natta catalyst to obtain an intermediate copolymer (intermediate copolymer). 0.05 parts by weight of Irganox 1010 (trade name: Ciba Specialty Chemicals) and 0.1 parts by weight of Irgafos 168 (trade name: Ciba Specialty Chemicals) were added to the intermediate copolymer and melt-kneaded to obtain copolymer (A1-1). The ethylene content of the resulting copolymer (A1-1) was 2.0 wt%. The MFR value of the resulting copolymer (A1-1) at 230°C / 2.16 kg was 25 g / 10 min, the melting point (Tm) was 152°C, and the crystallization temperature (Tc) was 119°C.

[0104] Copolymer (A1-2) was obtained in the same manner as in the production of copolymer (A1-1) described above, except that the blending amounts of propylene and ethylene were changed so that the ethylene content of (A1-2) was 1.5 wt%. The ethylene content of the obtained copolymer (A1-2) was 1.5 wt%. The MFR value of the obtained copolymer (A1-2) under the conditions of 230°C / 2.16 kg was 45 g / 10 min, the melting point (Tm) was 154°C, and the crystallization temperature (Tc) was 121°C.

[0105] Ethylene-propylene random copolymer (A2) As the copolymer (A2), the following copolymers (A2-1), (A2-2), and (A2-3) were used.

[0106] (A2-1) Vistamaxx Performance Polymer 6102 (manufactured by ExxonMobil) was used as the copolymer (A2-1). The ethylene content of this copolymer (A2-1) was 16.0 wt%. The MFR value of this copolymer (A2-1) at 230°C / 2.16 kg was 3 g / 10 min, and no melting point (Tm) or crystallization temperature (Tc) was observed.

[0107] (A2-2) Vistamaxx Performance Polymer 6502 (manufactured by ExxonMobil) was used as the copolymer (A2-2). The ethylene content of this copolymer (A2-2) was 13.0 wt%. The MFR value of this copolymer (A2-2) under the conditions of 230°C / 2.16 kg was 45 g / 10 min, the melting point (Tm) was 61°C, and the crystallization temperature (Tc) was 21°C.

[0108] (A2-3) Vistamaxx Performance Polymer 3980FL (manufactured by ExxonMobil) was used as the copolymer (A2-3). The ethylene content of this copolymer (A2-3) was 9.0 wt%. The MFR value of this copolymer (A2-3) under the conditions of 230°C / 2.16 kg was 8 g / 10 min, the melting point (Tm) was 76°C, and the crystallization temperature (Tc) was 27°C.

[0109] Polypropylene homopolymer (PP) SunAllomer (registered trademark) PLB00A (manufactured by SunAllomer Co., Ltd.) was used as the polypropylene homopolymer (PP). The MFR value of this propylene homopolymer under the conditions of 230°C / 2.16 kg was 70 g / 10 min, the melting point (Tm) was 167°C, and the crystallization temperature (Tc) was 128°C.

[0110] [Examples 1 to 12, Comparative Examples 1 to 10] Using an extruder (Ikegai Corporation FS30) with a diameter of 30 mm, each blending component was charged into the extruder according to the formulation shown in Tables 1 to 5, and melt extrusion was performed at a screw rotation speed of 100 rpm and a melt extrusion temperature of 200°C to obtain filaments for three-dimensional modeling with a diameter of 0.75 mm in Examples 1 to 12 and Comparative Examples 1 to 10. In the components shown in Tables 1 to 5, "-" indicates that no blend was used. In Examples 1 to 12, copolymers (A1) and (A2) were blended as copolymer (A).

[0111] The measurement and evaluation items for the filaments for three-dimensional modeling of Examples 1 to 12 and Comparative Examples 1 to 10 were MFR, melting point (Tm), crystallization temperature (Tc), flexibility, high-speed modeling property (surface smoothness), high-speed modeling property (appearance shape), and high-speed modeling property (extrusion rate). Each item is explained below. In the evaluations in Tables 4 and 5, "-" indicates that no measurement was performed.

[0112] [MFR value] The obtained filament for three-dimensional modeling was used to measure the MFR under the conditions of 230°C / 2.16 kg in accordance with JIS K7210.

[0113] Melting point (Tm) The obtained filament for three-dimensional modeling was heated to 200°C, cooled to -10°C at a rate of 10°C / min, and then heated again at a rate of 10°C / min, and the melting point (Tm) was measured using a differential scanning calorimeter (DSC).

[0114] [Crystallization temperature (Tc)] The obtained filament for three-dimensional modeling was heated to 200°C and then cooled at a rate of 10°C / min using a differential scanning calorimeter (DSC) to measure the crystallization temperature (Tc).

[0115] [Flexibility (deformation amount)] The resulting 3D modeling filament was used in a 3D printer (modeling device) manufactured by Mutoh Engineering, Inc., Value 3D Magix MF-2000. The melt extrusion temperature was set to 250°C, the layer pitch to 0.4 mm, and the modeling speed to 1000 mm / min. Layers were stacked one by one on a substrate to obtain plate-shaped test specimens measuring 150 mm in length, 10 mm in width, and 4 mm in thickness (150 mm x 10 mm x 4 mm). A cantilever beam with a protruding length of 100 mm was fabricated using the resulting test specimen. A 50 g load was applied to the tip, and the amount of deformation (vertical displacement) due to the load was measured as an index of flexibility. The resulting deformation was evaluated according to the following criteria. (Judgment criteria) A: Deformation between 10mm and 40mm (very good) B: Deformation amount is over 40mm and 50mm or less (good) C: Deformation is less than 10 mm or more than 50 mm (poor)

[0116] [High-speed modeling (surface smoothness)] Using the obtained 3D modeling filament, a NIPPON CORPORATION Smart-3D Printer NF-700D was used as a 3D printer (modeling device) with a melt extrusion temperature of 250°C, a layer pitch of 0.4 mm, and a modeling speed of 2000 mm / min. Layers were stacked one by one on a substrate to obtain a cylindrical model measuring 100 mm in diameter, 100 mm in height, and 4 mm in wall thickness as a test specimen. The surface of the obtained test specimen was visually inspected and evaluated according to the following criteria. (Judgment criteria) A: No roughness was observed on the surface, and no problems were found with the surface smoothness (very good) B: Slight surface roughness was observed, but no problems were observed with the surface smoothness (good) C: Roughness of the surface was clearly observed, and problems with the surface smoothness were recognized (poor)

[0117] [High-speed modeling (exterior shape)] Using the obtained three-dimensional modeling filament, a 3D printer (modeling device) was used, a Smart-3D Printer NF-700D manufactured by NIPPON CORPORATION, with the melt extrusion temperature set to 250°C, the layer pitch set to 0.4 mm, and the modeling speed set to 2000 mm / min. Layers were stacked one by one on a substrate to obtain a cylindrical model measuring 50 mm in diameter, 50 mm in height, and 4 mm in wall thickness as a test specimen. The external appearance (stringiness, deformation) of the obtained test specimen was visually inspected and evaluated according to the following criteria. (Judgment criteria) A: No stringiness or deformation is observed, and no problems with the appearance are found (very good) B: Slight stringiness and deformation were observed, but no problems were observed in the appearance (good) C: Stringiness or deformation was observed, and problems with the appearance were found (poor)

[0118] [High-speed buildability (discharge rate)] The obtained three-dimensional modeling filament was used as a 3D printer (modeling device) using a Smart-3D Printer NF-6100S manufactured by NIPPON CORPORATION. The melt extrusion temperature was set to 250°C, the layer pitch to 0.4 mm, and the modeling speed to 3600 mm / min. The filament was extruded and the high-speed modeling performance (extrusion rate) was evaluated. Specifically, during the extrusion of the three-dimensional modeling filament, the actual feed length of the three-dimensional modeling filament (actual feed length (L1)) was measured, and the ratio of L1 to the preset feed length of the three-dimensional modeling filament (preset feed length (L2)) was calculated as the extrusion rate of the three-dimensional modeling filament, as shown in the following formula: Discharge rate (%)=L1 / L2 × 100

[0119] [Table 1]

[0120] [Table 2]

[0121] [Table 3]

[0122] [Table 4]

[0123] [Table 5]

[0124] The filaments for three-dimensional modeling of Examples 1 to 12, which contain copolymer (A1) and copolymer (A2) and have a total ethylene content of 6 to 11% by weight, were shown to be excellent in flexibility and all three aspects of high-speed modeling properties: high-speed modeling properties (surface smoothness), high-speed modeling properties (appearance shape), and high-speed modeling properties (extrusion rate).

[0125] The results of the three-dimensional printing filaments of Examples 1 to 12 showed that when the MFR value is 30 to 60 g / 10 min, the three-dimensional printing filament has fluidity suitable for high-speed printing of an object with excellent flexibility. Furthermore, when the MFR value of copolymer (A1) is 10 to 60 g / 10 min and the MFR value of copolymer (A2) is 1 to 60 g / 10 min, the three-dimensional printing filament containing these two copolymers has fluidity suitable for high-speed printing of an object with excellent flexibility.

[0126] The results of Examples 11 and 12 showed that by further containing polypropylene homopolymer, the filament for three-dimensional modeling contains three types of components with different crystallinity: copolymer (A1), copolymer (A2), and polypropylene homopolymer, which broadens the range of crystallinity adjustment. This allows for detailed adjustment of the crystallinity, which is correlated with the melting point and fluidity, making it possible to rapidly manufacture objects with high precision and excellent flexibility.

[0127] In contrast, the filaments for three-dimensional modeling of Comparative Examples 1 and 2, which did not contain copolymer (A2) and had a total ethylene content of less than 6% by weight, were too hard and therefore had poor flexibility, and also had rough surfaces, indicating that they were poor in high-speed modeling properties (surface smoothness).

[0128] The filaments for three-dimensional modeling of Comparative Examples 3 and 4, which did not contain copolymer (A1) and had a total ethylene content of more than 11% by weight, were too soft and therefore poor in flexibility, and stringiness and deformation were observed during high-speed modeling, indicating that they were also poor in high-speed modeling properties (appearance shape). Furthermore, a comparison of Comparative Examples 3 and 4 showed that when a copolymer (A2) with a low MFR value was used (Comparative Example 3), high-speed stability (surface smoothness) tended to decrease.

[0129] The filament for three-dimensional modeling of Comparative Example 5, which did not contain copolymer (A1) and had a total ethylene content of 6 to 11% by weight, had excellent flexibility, but exhibited surface roughness, stringiness, and deformation during high-speed modeling, indicating poor high-speed modeling properties (surface smoothness, external shape). In other words, even if the total ethylene content satisfied the requirement of 6 to 11% by weight, a filament containing only one of the two copolymers (A1) and (A2) was shown to have poor high-speed modeling properties.

[0130] The filament for three-dimensional modeling of Comparative Example 6, which did not contain copolymers (A1) and (A2) but contained a polypropylene homopolymer, was too hard and therefore had poor flexibility, and in addition, surface roughness was observed during high-speed modeling, indicating that it also had poor high-speed modeling properties (surface smoothness).

[0131] The filaments for three-dimensional modeling of Comparative Examples 7 and 9, which contain copolymers (A1) and (A2) but have a total ethylene content of less than 6% by weight, are too hard and therefore have poor flexibility, and in addition, surface roughness was observed during high-speed modeling, indicating that they are also poor in high-speed modeling properties (surface smoothness).

[0132] The filaments for three-dimensional modeling of Comparative Examples 8 and 10, which contain copolymers (A1) and (A2) but have a total ethylene content of more than 11% by weight, are too soft and therefore have poor flexibility, and they are subject to stringing and deformation during high-speed modeling, indicating that they have poor high-speed modeling properties (external shape). [Industrial Applicability]

[0133] The filament for three-dimensional printing of the present invention is useful for forming three-dimensional objects using an extrusion lamination system, and objects formed by extrusion lamination using the filament for three-dimensional printing can have good appearance even at high printing speeds. Therefore, the present invention is suitable for various accessories, miscellaneous items such as dolls, interior appliances such as lighting covers, cases and covers for precision instruments such as cameras, clocks, measuring instruments, and display instruments, medical components for supporting the body, etc., and the industrial effects of the present invention are extremely significant.

Claims

1. A filament for three-dimensional shaping containing an ethylene-propylene random copolymer (A), The ethylene-propylene random copolymer (A) contains an ethylene-propylene random copolymer (A1) and an ethylene-propylene random copolymer (A2), the ethylene content (wt%) in the ethylene-propylene random copolymer (A2) is 5 times or more the ethylene content (wt%) in the ethylene-propylene random copolymer (A1); the total content of ethylene derived from the ethylene-propylene random copolymer (A) is 6 to 11% by weight, A filament for three-dimensional modeling having an MFR value of 32 to 51 g / 10 min measured under conditions of 230°C / 2.16 kg load in accordance with JIS K7210.

2. the ethylene-propylene random copolymer (A1) has an MFR value of 10 to 60 g / 10 min, as measured in accordance with JIS K7210 under conditions of 230°C and a load of 2.16 kg; The filament for three-dimensional shaping according to claim 1, wherein the MFR value of the ethylene-propylene random copolymer (A2) is 1 to 60 g / 10 min.

3. The filament for three-dimensional shaping according to claim 1 or 2, further comprising a polypropylene homopolymer.

4. A molded object using a three-dimensional modeling filament described in any one of claims 1 to 3.

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