Molding material

Abstract

To provide a molding material excellent in mechanical strength and color matching properties when being made to a molded product.SOLUTION: A molding material contains a resin and a cellulose. The resin contains an aliphatic polyester and a polyester elastomer, the cellulose contains a cellulose having an aspect ratio of less than 6, and an average total length of the cellulose is less than 500 μm.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a molding material. [Background technology]

[0002] Conventionally, molding materials containing cellulose and resin have been known. For example, Patent Document 1 discloses a natural fiber reinforced polyester material containing an aliphatic polyester, an elastomer, and pulp. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-272783 Summary of the Invention [Problem to be solved by the invention]

[0004] However, conventional molding materials have not been able to produce molded articles that have both excellent mechanical strength and excellent color-tuning properties. [Means for solving the problem]

[0005] One aspect of the molding material according to the present invention is A molding material comprising a resin and cellulose, the resin includes an aliphatic polyester and a polyester-based elastomer, The cellulose comprises cellulose having an aspect ratio of less than 6; The average overall length of the cellulose is less than 500 μm. [Brief explanation of the drawings]

[0006] [Figure 1] Table 1 shows the raw material compositions and evaluation results for the molding materials of each Example and Comparative Example. [Figure 2]Table 2 shows the raw material compositions and evaluation results for the molding materials of each Example and Comparative Example. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments of the present invention will be described. The embodiments described below are examples of the present invention. The present invention is not limited to the following embodiments, and includes various modified forms that are implemented within the scope of the present invention. Note that not all of the configurations described below are necessarily essential configurations of the present invention.

[0008] In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0009] 1.Molding materials A molding material according to one embodiment of the present invention is a molding material comprising a resin and cellulose, wherein the resin comprises an aliphatic polyester and a polyester-based elastomer, the cellulose comprises cellulose having an aspect ratio of less than 6, and the average total length of the cellulose is less than 500 μm.

[0010] In molding materials containing resin and cellulose, polyester elastomer, which is a soft resin, is sometimes used to improve impact resistance (toughness). Since the compatibility between elastomers and cellulose is poor, interfacial delamination occurs. Therefore, aliphatic polyesters are added to promote interfacial control (compatibility) between the polyester elastomer and cellulose.

[0011] Among synthetic resins, aliphatic polyesters are the most biomass-based, and choosing a biomass-based material makes it easier to reduce the environmental impact. However, because aliphatic polyesters are polar, they tend to thicken when mixed with cellulose, and the heat generated by shear during mixing can burn the cellulose, discoloring the molding material and impairing its color-matching properties.

[0012] Therefore, the inventors conducted further intensive research and found that when cellulose with an aspect ratio of less than 6 is included, the thickening of the material during kneading is reduced, and the heat generated by shear is reduced, thereby suppressing scorching of the cellulose and providing excellent color-tuning properties to the molding material.

[0013] The molding material can be molded using known molding methods such as injection molding and press working. Molded products made from the molding material are suitable as replacements for polystyrene and the like for various containers, sheets, and housings for office equipment such as printers and home appliances.

[0014] Each component contained in the molding material will be described below.

[0015] 1.1 Resin The molding material according to this embodiment contains a resin, and the resin contains an aliphatic polyester and a polyester-based elastomer.

[0016] Polyester elastomers act as a resin matrix, ensuring the impact resistance (toughness) of molded products. However, they have low compatibility with cellulose, making them prone to interfacial delamination. Therefore, by using aliphatic polyesters, they function as a compatibilizer between cellulose and polyester elastomers, preventing interfacial delamination.

[0017] The resin content is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, based on the total amount of the molding material. If the resin content is within the above range, the viscosity tends to increase during kneading, making color-tuning problems more likely to occur. However, the molding material according to this embodiment tends to have excellent color-tuning properties even in such cases. The lower limit of the resin content is not particularly limited, but is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, based on the total amount of molding material.

[0018] 1.1.1 Aliphatic polyesters The resin contains an aliphatic polyester. The aliphatic polyester has thermoplastic properties and functions to melt and bond cellulose together when producing a molded article from the molding material. The aliphatic polyester, together with the cellulose, is responsible for the physical properties of the molded article.

[0019] The aliphatic polyester is not particularly limited, and may be a saturated aliphatic polyester or an unsaturated aliphatic polyester. The aliphatic polyester may be linear or cyclic. Among these, the aliphatic polyester is preferably a saturated aliphatic polyester. The aliphatic polyester is also preferably a highly polar polyester.

[0020] The content of the aliphatic polyester is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, based on the total amount of the molding material. The content of the aliphatic polyester is preferably 50% by mass or less, more preferably 45% by mass or less, and even more preferably 40% by mass or less, based on the total amount of the molding material. When the content of the aliphatic polyester is within the above range, excellent color toning properties can be obtained and better mechanical strength tends to be obtained.

[0021] 1.1.1.1 Saturated aliphatic polyesters The saturated aliphatic polyester is not particularly limited, but is preferably one having a linear or branched alkylene group, and more preferably a linear alkyl polyester having a linear alkylene group. Such linear alkyl polyesters tend to have increased toughness due to the linear alkylene group, and mainly to improve the impact strength of molded articles.

[0022] The saturated aliphatic polyester preferably contains, as raw material monomers, an alkyl dicarboxylic acid having an alkylene group with 2 to 8 carbon atoms and an alkylene diol having 2 to 8 carbon atoms, more preferably an alkyl dicarboxylic acid having an alkylene group with 2 to 5 carbon atoms and an alkylene diol having 3 to 5 carbon atoms, and even more preferably an alkyl dicarboxylic acid having an alkylene group with 2 to 3 carbon atoms and an alkylene diol having 3 to 4 carbon atoms. When the saturated aliphatic polyester contains the above raw material monomers, better mechanical strength tends to be obtained. The saturated aliphatic polyester is preferably formed by copolymerizing the above two raw material monomers, and the copolymerization can be carried out by a known synthesis method.

[0023] Examples of the alkyl dicarboxylic acid include linear saturated aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid. It is preferable to use one or more of these to synthesize the saturated aliphatic polyester.

[0024] Examples of the alkylene diol include dihydric alcohols such as 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, and 1,8-octanediol. It is preferable to use one or more of these to synthesize saturated aliphatic polyesters. The two raw material monomers mentioned above are relatively easy to obtain and can be used for industrial or commercial purposes.

[0025] The saturated aliphatic polyester preferably contains at least one of polybutylene succinate, polybutylene succinate adipate, and polyethylene diadipate. These saturated aliphatic polyesters are biodegradable, which reduces the environmental impact of molded products and tends to provide better mechanical strength.

[0026] The weight average molecular weight of the saturated aliphatic polyester is not particularly limited and may be 5,000 or more, 10,000 or more, or 50,000 or more. The weight average molecular weight of the saturated aliphatic polyester may be 200,000 or less, 150,000 or less, or 100,000 or less.

[0027] 1.1.1.2 Highly polar polyester The highly polar polyester is an aliphatic polyester having a molecular structure with a relatively high polarity, and preferably has a repeating structure derived from the raw material monomer in which the number of oxygen atoms is 1 or more for every 2 carbon atoms. Specifically, the highly polar polyester is a polyester containing, as raw material monomers, lactic acid, hydroxybutyric acid, oxysuccinic acid, citric acid, malonic acid, succinic acid, serine, threonine, acrylonitrile, hydroxypropyl methylcellulose, hydroxypropyl cellulose, hydroxypropyl methyl ... Preferably, the starting monomers include vinyl acetate, methyl acrylate, and vinyl acetate.

[0028] Specifically, the highly polar polyester preferably contains one or more of polylactic acid, polyhydroxybutyric acid, polyacrylic acid, polymethyl acrylate, and polyvinyl acetate. The highly polar polyester may also be a copolymer having a structure derived from lactic acid or acetic acid in its molecular structure, such as polyethylene succinic acid. Among these, the highly polar polyester preferably contains one or more of polylactic acid and polyhydroxybutyric acid. Such compounds tend to be biodegradable, reduce environmental impact, and exhibit better mechanical strength.

[0029] 1.1.2 Polyester elastomers The resin contains a polyester-based elastomer. The polyester-based elastomer serves as the resin matrix and ensures the impact resistance (toughness) of the molded body. However, it has low compatibility with cellulose, and the two tend to peel at the interface. Therefore, by using the above-mentioned aliphatic polyester, it functions as a compatibilizer between cellulose and the polyester-based elastomer, preventing interfacial peeling.

[0030] Polyester-based elastomers have thermoplastic properties and melt to bond cellulose when molding materials are used to produce molded articles. In addition, polyester-based elastomers, together with cellulose, contribute to the physical properties of molded articles. In particular, polyester-based elastomers enhance the toughness and impact strength of molded articles. Furthermore, polyester-based elastomers have the potential to be produced and used as bioplastics in the future, making them a promising material for reducing environmental impact.

[0031] The polyester elastomer preferably contains, as raw material monomers, an alkyldicarboxylic acid or phthalic acid having an alkylene group with 2 to 8 carbon atoms, and an alkylene diol having an alkylene group with 2 to 8 carbon atoms. When the polyester elastomer contains the above raw material monomers, better mechanical strength tends to be obtained. The polyester elastomer is preferably formed by copolymerizing the above two raw material monomers, which can be carried out by a known synthesis method.

[0032] Examples of the alkyl dicarboxylic acid include straight-chain saturated aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacic acid. These alkyl dicarboxylic acids may have a substituent in their molecular structure. It is preferable to use one or more of these alkyl dicarboxylic acids to synthesize polyester elastomers.

[0033] The phthalic acid may have a substituent in the molecular structure.

[0034] Examples of the alkylene diol include dihydric alcohols such as 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, and 1,8-octanediol. It is preferable to use one or more of these to synthesize polyester elastomers. The three raw material monomers mentioned above are relatively easy to obtain and can be used for industrial or commercial purposes.

[0035] The polyester elastomer may contain other raw material monomers in addition to the above-mentioned raw material monomers. Examples of the other raw material monomers include styrene, butadiene, acrylic acid, acrylic acid esters, methacrylic acid, methacrylic acid esters, acetonitrile, and isobutylene. Examples of the monomers include ethylene, isoprene, and ethylene, and it is preferable to use one or more of these. When such other raw material monomers are included, better mechanical strength tends to be obtained.

[0036] When other raw material monomers are incorporated into the polyester elastomer, the total moles of the other raw material monomers is preferably 1% or more and less than 50% of the total moles of the raw material monomers, which tends to result in better mechanical strength.

[0037] Commercially available polyester elastomers may be used. Examples of such commercially available products include ES-A60NX, E-D27N, E-D42N, and ES series (all trade names) manufactured by Aronkasei Co., Ltd. One or more of these may be used as the polyester elastomer.

[0038] Here, the presence or absence of a polyester-based elastomer in the molding material or molded article can be determined by the following physical property analysis and component analysis.

[0039] First, physical property analysis is performed to confirm the presence or absence of components with a composite modulus of elasticity of 100 MPa or less. If such components are present, it is determined that an elastomer component is present. Specifically, for example, a scanning probe microscope NX20 from Park Systems Japan is used to measure the cross section of the molding material or molded body in contact mode. This makes it possible to confirm the presence or absence of a component with a composite modulus of elasticity of 100 MPa. A known nanoindenter may also be used to confirm the presence or absence of an elastomer component.

[0040] Next, a qualitative analysis using a combination of pyrolysis gas chromatography mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-IR) is performed to determine whether the elastomer component is a polyester elastomer. Pyrolysis GC-MS is an analytical method that identifies the various fragments generated by pyrolysis of a sample. FT-IR is an analytical method that identifies the molecular structure of a sample from its infrared absorption spectrum. These methods make it possible to identify the molecular structure of a sample.

[0041] For pyrolysis GC-MS, for example, a Frontier Labs Multi-Shot Pyrolyzer EGA / PY-3030D and an Agilent Technologies GC / MS 5975 equipped with the device are used, and for FT-IR, for example, a Thermo Fisher Nicolet® 380 Continuμm® spectrometer is used.

[0042] 1.1.3 Other resins The resin contained in the molding material according to the present embodiment may contain resins other than those mentioned above, such as olefin-based resins such as polyethylene and polypropylene, urethane-based resins, and acrylic-based resins.

[0043] 1.2 Cellulose The molding material according to this embodiment contains cellulose, and the cellulose has an aspect ratio of less than 6 and an average total length of less than 500 μm.

[0044] Cellulose functions as a filler in molded products, increasing the bulk of the molding material and improving the physical properties of the molded products, such as their strength.

[0045] Cellulose is derived from plants and is a relatively abundant natural material. Therefore, the use of cellulose promotes a reduction in the environmental impact compared to the use of synthetic fillers. Cellulose is also advantageous in terms of raw material procurement and cost. Theoretically, cellulose has high strength and contributes to improving the strength of molded products. In addition to using virgin pulp as cellulose, recycled paper, old cloth, etc. may also be used. Commercially available products may also be used.

[0046] The molecular structure of cellulose may contain components other than cellulose, such as hemicellulose and lignin. The cellulose may also be subjected to a process such as bleaching.

[0047] The cellulose contained in the molding material according to this embodiment has an average total length of less than 500 μm. If the average total length of the cellulose is less than 500 μm, the coloring of the cellulose itself is reduced, and the molding material can have excellent color-tuning properties.

[0048] The average total length of cellulose refers to the average of the longest points of the length, width, and height of the cellulose shape. That is, the average total length of cellulose refers to the average of the longest side length or the average of the largest diameter of cellulose. Specifically, if the shape of cellulose is, for example, fibrous, it is the average fiber length; if the shape is, for example, scale-like, it is the average of the vertical side length (longest side length); and if the shape is, for example, spherical, it is the average of the largest diameter. Note that, if the fiber is curved, the fiber length refers to the distance along the curve.

[0049] The "average" may be a number average, a length weighted average, or a length-length weighted average.

[0050] The average total length of cellulose can be determined using the following method. For example, using a Hitachi High-Technologies Corporation scanning electron microscope (S-4700), calibration is performed using an EM Japan calibration standard (S2009T) and the length of 100 randomly selected cellulose particles is measured. It can also be determined using a Seishin Enterprises Corporation particle shape image analyzer (PITA-04) by placing 50 mL of a dispersion containing 0.05-0.1 wt% of the sample in the analyzer and measuring the length. When the cellulose is fibrous, the average fiber length of the cellulose is determined according to ISO 16065-2:2007.

[0051] The average total length of the cellulose is not particularly limited as long as it is less than 500 μm, but is preferably 400 μm or less, more preferably 300 μm or less, even more preferably 200 μm or less, particularly preferably 150 μm or less, and more particularly preferably 100 μm or less. When the average total length is within the above range, the color toning property of the molding material may be improved.

[0052] The total length distribution width of cellulose ((D90-D10) / D50) is not particularly limited, but is preferably 5.0 or less, more preferably 4.0 or less, even more preferably 3.0 or less, particularly preferably 2.0 or less, and even more particularly preferably 1.5 or less. D10, D50, and D90 represent the total lengths corresponding to 10%, 50%, and 90%, respectively, of the cumulative volume frequency calculated from the shortest total length of cellulose.

[0053] The total length distribution width of cellulose can be determined by the following method. For example, it can be determined using an ABB "L&W Fiber Tester Plus" by placing 300 mL of a dispersion containing 0.1 wt% of the sample in the instrument and measuring it. It can also be determined using a Microtrac-Bell laser diffraction particle size distribution analyzer "MT3300EXII" by placing 20 mL of a dispersion containing 0.05-0.1 wt% of the sample in the instrument and measuring it using laser diffraction / Mie scattering.

[0054] The crystalline structure of cellulose is not particularly limited and may be type I, type II, type III, type IV, or amorphous. However, type I is preferred for fibrous cellulose, type II is preferred for spherical cellulose, and amorphous is preferred for scaly cellulose.

[0055] The crystallinity of cellulose is not particularly limited, but is preferably 50 to 90%, more preferably 55 to 80%, and particularly preferably 60 to 75%. The crystallinity of cellulose can be calculated, for example, from each peak area (e.g., 2θ=22.6° for cellulose type I, 2θ=20.2° for cellulose type II) obtained using an X-ray diffractometer "PANalytical X'PERT" manufactured by Malvern Panalytical and a sealed X-ray tube (Cu, output 40 kV, 40 mA).

[0056] The cellulose contained in the molding material according to this embodiment includes cellulose having an aspect ratio of less than 6. When the cellulose includes cellulose having an aspect ratio of less than 6, the increase in viscosity of the material during kneading is reduced, and the heat generated by shearing is reduced, thereby suppressing scorching of the cellulose, and the molding material can have excellent color toning properties.

[0057] The aspect ratio of cellulose refers to the ratio of the longer two of the length, width, and height of the shape of the cellulose. Specifically, if the shape of the cellulose is, for example, fibrous, it is the value obtained by dividing the fiber length by the fiber width. If the shape of the cellulose is, for example, scaly, it is the value obtained by dividing the vertical side length (longest side length) by the horizontal side length. If the shape of the cellulose is, for example, spherical, it is the value obtained by dividing the longest diameter of the three diameters by the next longest diameter. In this way, the thickness direction is not taken into account when calculating the aspect ratio.

[0058] The aspect ratio of cellulose can be determined by the same measurement method as for the average overall length of cellulose.

[0059] In cellulose having an aspect ratio of less than 6, the aspect ratio is not particularly limited as long as it is less than 6, but preferably the aspect ratio is 5 or less, more preferably the aspect ratio is 4 or less, even more preferably the aspect ratio is 3 or less, particularly preferably the aspect ratio is 2 or less, and even more particularly preferably the aspect ratio is 1.5 or less.

[0060] The shape of the cellulose having an aspect ratio of less than 6 is not particularly limited, but is preferably at least one selected from fibrous, scaly, and spherical shapes. In the molding material according to this embodiment, as long as the cellulose contains cellulose having an aspect ratio of less than 6, the molding material can have excellent color-tuning properties regardless of its shape.

[0061] The content of cellulose having an aspect ratio of less than 6 is preferably 70% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, particularly preferably 95% by mass or more, and even particularly preferably 100% by mass, relative to the total amount of cellulose contained in the molding material. When the content of cellulose having an aspect ratio of less than 6 is within the above range, the color toning properties of the molding material tend to be more excellent.

[0062] The cellulose content is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass or more, based on the total amount of the molding material. The cellulose content is preferably 90% by mass or less, more preferably 80% by mass or less, even more preferably 70% by mass or less, and particularly preferably 65% ​​by mass or less, based on the total amount of the molding material. When the cellulose content is within the above range, the viscosity tends to increase during kneading, and color matching problems are more likely to occur. However, the molding material according to this embodiment tends to have excellent color matching properties even in such cases.

[0063] The amount of cellulose in the molding material can be measured by dissolving the molding material in chloroform solvent, measuring the weight of the residue to quantify the total amount of composite filler, and then quantifying the amount of cellulose in the composite filler by fluorescent X-ray analysis (for example, JEOL "JSX-1000S").

[0064] 1.3 Inorganic fillers The molding material according to the present embodiment may further contain an inorganic filler. When an inorganic filler is contained, the viscosity may increase during kneading, which may make the color-tuning problem more likely to occur. However, the molding material according to the present embodiment tends to have excellent color-tuning properties even in such cases.

[0065] Examples of inorganic fillers include particles made of inorganic materials such as metals such as aluminum; silicates such as clay, talc, mica, kaolin, zeolite, calcium silicate, montmorillonite, and bentonite; oxides such as silica, diatomaceous earth, aluminum oxide, zirconium oxide, barium ferrite, barium oxide, and pumice; hydroxides such as aluminum hydroxide, magnesium hydroxide, and basic magnesium carbonate; carbonates such as calcium carbonate, magnesium carbonate, dolomite, and dawsonite; sulfates or sulfites such as calcium sulfate, barium sulfate, and calcium sulfite; and fibers made of inorganic materials such as glass fibers.

[0066] The volume average particle size of the inorganic filler is not particularly limited, but is preferably 0.1 μm or more and 100 μm or less, more preferably 0.1 μm or more and 50 μm or less, and even more preferably 0.1 μm or more and 10 μm or less.

[0067] When an inorganic filler is contained, the content thereof is preferably 1 to 20 mass %, more preferably 3 to 17 mass %, further preferably 5 to 15 mass %, and particularly preferably 7 to 12 mass %, relative to the total amount of the molding material.

[0068] 1.4 Other ingredients The molding material according to this embodiment may contain components such as colorants, flame retardants, insect repellents, mildew inhibitors, antioxidants, ultraviolet absorbers, aggregation inhibitors, and mold release agents.

[0069] 1.5 Physical Properties The molding material according to this embodiment preferably has a complex viscosity at 170°C of 600 to 80,000 Pa·sec, more preferably 600 to 40,000 Pa·sec, even more preferably 600 to 20,000 Pa·sec, still more preferably 600 to 10,000 Pa·sec, and particularly preferably 1,000 to 5,000 Pa·sec. When the complex viscosity at 170°C is within the above range, the color toning properties of the molding material tend to be more excellent.

[0070] The method for measuring the complex viscosity is not particularly limited. For example, the complex viscosity can be determined in accordance with JIS K7244-10 (ISO 6721-10) by measuring the viscoelasticity using an "ARES-G2" manufactured by TAINSTRUMENTS under the conditions of a measurement temperature of 170°C, a frequency of 1 Hz, and a strain of 8%.

[0071] 2. Manufacturing method of molding material A method for producing the molding material will now be described. A known method can be applied to the production of the molding material. Specifically, for example, the following method can be applied.

[0072] First, the raw materials (each component of the molding material) are mixed in a single-screw or twin-screw mixer. The mixture is then pelletized to form pellets of molding material.

[0073] The following method may also be used to manufacture molding materials. First, waste paper or pulp material is roughly crushed in a shredder to produce cellulose. Then, the cellulose and a resin containing an aliphatic polyester and a polyester-based elastomer are weighed and kneaded. Next, the kneaded raw materials are deposited in air to produce a sheet-like deposit. Since the deposit contains a large amount of air and has a low density, it is compressed in a calendar device to remove the air and increase the density. Next, the deposit is heated non-contact using a heating furnace, and then hot-pressed in a heat press device.

[0074] In the heating furnace and heat press device, it is preferable to heat at a temperature about 20°C higher than the melting temperature of the resin, which tends to form a sheet in which the raw materials are dispersed evenly.

[0075] Next, the sheet is cut into a desired shape using a shredder device to produce pellet-shaped molding material. The desired shape of the molding material is not particularly limited, but is generally a roughly cubic shape ranging from 2 mm cube to 5 mm cube. The molding material is produced by the above method. Note that the manufacturing method of the molding material is not limited to the above.

[0076] 3. Working Example The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "%" below is based on mass.

[0077] 3.1 Production of molding materials and evaluation samples According to the compositions in Tables 1 and 2, molding materials according to the examples and comparative examples were produced.

[0078] Specifically, each component was fed into a Technovel twin-screw kneader "KZW15TW-45MG" and kneaded to obtain the composition shown in Tables 1 and 2. The kneading conditions were a maximum heating temperature of 180°C and an extrusion rate of 1 kg / hr. The mixture was then processed into strands and pelletized using a pelletizer to produce pelletized molding material.

[0079] The molding materials according to each example and comparative example were used to carry out molding by injection molding or press processing. Specifically, the heating temperature of the molding material was 200°C for both injection molding and press processing. The injection molding machine used was a "THX40-5V" manufactured by Nissei Plastic Industrial Co., Ltd., and the press processing machine used was a hydraulic press "PHKS-40ABS" manufactured by Towa Seiki Co., Ltd.

[0080] The following provides additional explanations for the descriptions in Tables 1 and 2. Polyester elastomer (product name "ES-A60NX", Aronkasei Co., Ltd.) Polybutylene succinate FZ71 (trade name "BioPBS FZ71", manufactured by Mitsubishi Chemical Corporation, weight-average molecular weight MW70000) Polybutylene succinate FZ91 (trade name "BioPBS FZ91", manufactured by Mitsubishi Chemical Corporation, weight-average molecular weight MW92000) Polyhydroxyalkane (P3HBH, poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate]) EPDM (ethylene propylene diene rubber, product name "NOLDEL (registered trademark) 3720P", Dow Toray Industries, Inc.) 200 μm spherical (Rengo Co., Ltd. Viscopearl "D-2010", aspect ratio 1.0, distribution width 1.2, crystallization rate 65-70%, type II crystal structure) 30 μm spherical (Rengo Co., Ltd. Viscopearl "D-30", aspect ratio 1.0, distribution width 1.8, crystallization rate 70-75%, type II crystal structure) 5 μm spherical (Rengo Co., Ltd. Viscopearl "D-5", aspect ratio 1.0, distribution width 1.1, crystallization rate 70-75%, type II crystal structure) 40μm scales (CMPC "Guaiba BEKP" processed with West Co., Ltd. "KGW-G015", aspect ratio 1.5, distribution width 3.8, crystallization rate 0-10%, non-crystalline) 350μm fibrous (CMPC's "Guaiba BEKP" defibrated in a twin-screw mixer, aspect ratio: 17.5, distribution width: 1.0, crystallization rate: 58-65%, I-type crystal structure) 200 μm fibrous (Nippon Paper Industries Co., Ltd. "KC Flock W-80", aspect ratio 5.0, distribution width 3.5, crystallinity 63-67%, I-type crystal structure) 140 μm fibrous (Nippon Paper Industries Co., Ltd. "KC Flock W-100", aspect ratio 7.0, distribution width 3.2, crystallinity 63-67%, I-type crystal structure) 40 μm fibrous (Nippon Paper Industries Co., Ltd. "KC Flock W-300G", aspect ratio 6.7, distribution width 2.5, crystallinity 63-67%, I-type crystal structure) 10 μm fiber (Nippon Paper Industries Co., Ltd. "NP Fiber W-6", aspect ratio 4.7, distribution width 1.5, crystallinity 65-69%, I-type crystal structure) Talc (Nippon Talc Co., Ltd. "Nano Ace", volume average particle size 1.5 μm) Calcium carbonate (Takehara Chemical Industry Co., Ltd., volume average particle size 4.5 μm)

[0081] The total length and aspect ratio of cellulose were measured using a scanning electron microscope (S-4700) manufactured by Hitachi High-Tech Corporation, with ruler calibration performed in the SEM using a calibration standard (S2009T) manufactured by EM Japan. The lengths of 100 randomly selected cellulose particles were measured and calculated as the number average.

[0082] 3.2 Evaluation Test 3.2.1 Complex viscosity and injection moldability The viscoelasticity of the molding materials obtained in each of the Examples and Comparative Examples was measured in accordance with JIS K7244-10 (ISO 6721-10) using an "ARES-G2" manufactured by TAINSTRUMENTS under conditions of a measurement temperature of 170°C, a frequency of 1 Hz, and a strain of 8%, and the complex viscosity was determined. Based on the determined complex viscosity, the injection moldability was evaluated according to the following criteria. (Judgment criteria) A: Complex viscosity is less than 100 kPa·sec B: Complex viscosity is 100 kPa·sec or more and 1000 kPa·sec or less C: Complex viscosity is over 1000 kPa·sec

[0083] 3.2.2 Appearance and color matching The evaluation samples obtained above according to each of the examples and comparative examples were measured using a fluorescence spectrodensitometer (Konica Minolta, Inc., FD-7) * The values ​​were measured and judged according to the following criteria: A indicates good appearance and color toning. (Judgment criteria) A:L * is 70 or more C:L * is less than 70

[0084] 3.2.3 Charpy impact strength In the evaluation samples according to the examples and comparative examples obtained above, the shape of the test piece was a rectangular plate with a long side of 80 mm ± 2 mm, a short side of 4.0 mm ± 0.2 mm, and a thickness of 10.0 mm ± 0.2 mm. In accordance with ISO 179 (JIS K7111), the test was performed using Toyo Seiki Seisakusho's "Impact Tester IT" as the test equipment, with a hammer weight of 4 J (WR 2.14 N / m), a lifting angle of 150 °, a notch remaining width of 8.0 mm ± 0.2 mm, and a notch angle of 150 °. The Charpy impact strength was measured with the angle set at 45°.

[0085] 3.2.4 Overall evaluation Based on the evaluation results of the injection moldability, appearance, color matching, and Charpy impact strength, an overall evaluation was made according to the following criteria: A indicates good appearance and color matching, as well as good mechanical strength. (Judgment criteria) A: Injection moldability and appearance / color matching are A, and Charpy impact strength is 6kJ / m 2 End B: Injection moldability and appearance / color matching are A, and Charpy impact strength is 6 kJ / m 2 less than C: Injection moldability B D: Appearance and color matching are B E: Cannot be kneaded

[0086] 3.3 Evaluation results The evaluation results are shown in Tables 1 and 2.

[0087] From the results shown in Tables 1 and 2, the molding materials according to each example, which comprise a resin and cellulose, wherein the resin comprises an aliphatic polyester and a polyester-based elastomer, the cellulose comprises cellulose having an aspect ratio of less than 6, and the average total length of the cellulose is less than 500 μm, all had excellent mechanical strength and color adjustment properties when molded into molded products.

[0088] In contrast, the molding materials according to the comparative examples that did not satisfy the above-mentioned requirements were unable to achieve both mechanical strength and color-tuning ability when molded into a molded product.

[0089] The following can be derived from the above-described embodiment.

[0090] One aspect of the molding material is A molding material comprising a resin and cellulose, the resin includes an aliphatic polyester and a polyester-based elastomer, The cellulose comprises cellulose having an aspect ratio of less than 6; The average overall length of the cellulose is less than 500 μm.

[0091] In one embodiment of the molding material, The shape of the cellulose having an aspect ratio of less than 6 may be at least one selected from fibrous, scaly, and spherical shapes.

[0092] In any one of the above molding materials, The content of the cellulose having an aspect ratio of less than 6 may be 70% by mass or more relative to the total amount of the cellulose contained in the molding material.

[0093] In any one of the above molding materials, The molding material may have a complex viscosity at 170° C. of 600 to 80,000 Pa·sec.

[0094] In any one of the above molding materials, It may further contain an inorganic filler.

[0095] In any one of the above molding materials, The content of the resin may be 50% by mass or less relative to the total amount of the molding material.

[0096] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially the same as the configurations described in the embodiments, such as configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

Claims

1. A molding material comprising a resin and cellulose, the resin includes an aliphatic polyester and a polyester-based elastomer, The cellulose comprises cellulose having an aspect ratio of less than 6; A molding material, wherein the average total length of the cellulose is less than 500 μm.

2. The molding material according to claim 1 , wherein the cellulose having an aspect ratio of less than 6 has at least one shape selected from the group consisting of fibrous, scaly, and spherical.

3. The molding material according to claim 1 , wherein the content of the cellulose having an aspect ratio of less than 6 is 70% by mass or more relative to the total amount of the cellulose contained in the molding material.

4. The molding material according to claim 1, wherein the molding material has a complex viscosity at 170°C of 600 to 80,000 Pa·sec.

5. The molding material according to claim 1 , further comprising an inorganic filler.

6. The molding material according to claim 1 , wherein the content of the resin is 50% by mass or less based on the total amount of the molding material.

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