Molding material

Abstract

To provide a molding material that contains cellulose, and has excellent color-toning property.SOLUTION: A molding material contains biodegradable resin and cellulose, where the biodegradable resin contains polylactic acid and biodegradable polyester other than polylactic acid, the cellulose includes a first cellulose having a peak top in a region where a particle diameter in the volume-based particle size distribution curve is 3 μm or more and 100 μm or less, and a second cellulose having a peak top in a region where a particle diameter in the volume-based particle size distribution curve is 50 μm or more and 500 μm or less, and the particle diameter of the peak top of the first cellulose is smaller than particle diameter of the peak top of the second cellulose.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Attempts have been made to improve the strength of resin-based materials by blending them with cellulose. For example, Patent Document 1 discloses a natural fiber-reinforced polyester material containing an aliphatic polyester (polylactic acid), 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 biodegradable molding materials have not been able to produce molded articles that have both excellent mechanical strength and excellent color-tuning properties.

[0005] In particular, the colors of molded products made from conventional biodegradable molding materials are so-called earth colors, meaning that they easily blend into the natural environment. Therefore, even if the molded products were dumped into the environment, they would be difficult to notice. Combined with the fact that the materials are biodegradable, this could encourage consumers to inappropriately dump molded products into the environment. [Means for solving the problem]

[0006] One aspect of the molding material according to the present invention is A molding material comprising a biodegradable resin and cellulose, the biodegradable resin includes polylactic acid and a biodegradable polyester other than polylactic acid; The cellulose is a first cellulose having a peak top in a particle size range of 3 μm or more and 100 μm or less in a volume-based particle size distribution curve; a second cellulose having a peak top in a particle size range of 50 μm or more and 500 μm or less in a volume-based particle size distribution curve; Including, The particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose. [Brief explanation of the drawings]

[0007] [Figure 1] Table 1 shows the compositions, properties, and evaluation results of molding materials of Examples and Comparative Examples. [Figure 2] Table 2 shows the composition, properties, and evaluation results of molding materials of comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0008] The following describes embodiments of the present invention. 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.

[0009] 1.Molding materials The molding material according to this embodiment includes a resin and cellulose. The resin includes polylactic acid and a biodegradable polyester other than polylactic acid. The cellulose includes a first cellulose having a peak top in the particle size range of 3 μm to 100 μm in a volumetric particle size distribution curve, and a second cellulose having a peak top in the particle size range of 50 μm to 500 μm in a volumetric particle size distribution curve, and the peak top particle size of the first cellulose is smaller than the peak top particle size of the second cellulose.

[0010] 1.1. Biodegradable resin The molding material of this embodiment contains a biodegradable resin. The biodegradable resin can form a matrix in the molding material. The molding material is a composite material having a structure in which cellulose, which will be described later, is dispersed in the biodegradable resin.

[0011] The biodegradable resin includes polylactic acid and biodegradable polyesters other than polylactic acid. Polylactic acid and biodegradable polyesters other than polylactic acid have thermoplastic properties and melt to bond cellulose fibers together when producing molded articles from molding materials. Furthermore, polylactic acid and biodegradable polyesters other than polylactic acid, together with cellulose fibers, are responsible for the physical properties of the molded article. Furthermore, polylactic acid and biodegradable polyesters other than polylactic acid have the potential to be produced and used as bioplastics in the future, and are also expected to promote environmental load reduction.

[0012] 1.1.1.Polylactic acid Biodegradable resins include polylactic acid, which is a thermoplastic resin obtained by polymerizing lactic acid using the lactide method, direct polymerization, or the like. Examples of polylactic acid include poly-L-lactic acid, which is obtained by polymerizing only the L-form, poly-D-lactic acid, which is obtained by polymerizing only the D-form, and poly-DL-lactic acid, which is obtained by polymerizing both the L- and D-forms.

[0013] The content of polylactic acid is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, based on the total amount of molding material. Furthermore, the content of polylactic acid is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, based on the total amount of molding material. When the content of polylactic acid is within the above range, excellent color toning properties can be achieved, and better mechanical strength tends to be obtained.

[0014] 1.1.2. Polylactic acid and biodegradable polyesters other than polylactic acid The biodegradable polyester other than polylactic acid is not particularly limited as long as it has biodegradability, and may be, for example, a saturated aliphatic polyester or an unsaturated aliphatic polyester. The aliphatic polyester may be linear or cyclic. Among these, the biodegradable aliphatic polyester is preferably a saturated aliphatic polyester. The aliphatic polyester is also preferably a highly polar polyester.

[0015] Aliphatic polyesters are polyesters that do not have an aromatic ring, and examples thereof include polycondensates of aliphatic hydroxycarboxylic acids, polycondensates of aliphatic dicarboxylic acids and aliphatic diols, ring-opening polymers of aliphatic lactones, copolymers of multiple of these monomers, and transesterification products of these polymers. Furthermore, aliphatic polyesters may contain a structure derived from a monomer capable of forming three or more ester bonds, such as an aliphatic triol or an aliphatic tricarboxylic acid, or a monomer having an alicyclic skeleton.

[0016] Examples of biodegradable aliphatic polyesters include polylactic acids such as poly-L-lactic acid (PLLA), poly-D-lactic acid (PDLA), random copolymers of L-lactic acid and D-lactic acid, and stereocomplexes of L-lactic acid and D-lactic acid, polycaprolactone, polypivalolactone, polyhydroxybutyric acid (P3HB), polyhydroxyvaleric acid, poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] (P3HBH), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). hydroxyvalerate), polylactic acid-co-polyglycolic acid, polylactic acid-co-polycaprolactone, polyethylene succinate, polypropylene succinate, polybutylene succinate (PBS), polyethylene adipate, polypropylene adipate, polybutylene adipate (PBA), polyneopentyl glycol adipate, polyethylene sebacate, polypropylene sebacate, polybutylene sebacate, polyethylene succinate / adipate, polypropylene succinate / adipate, polybutylene succinate / adipate, and the like.

[0017] As a biodegradable polyester other than polylactic acid, a polyester-based elastomer may be used as long as it is biodegradable. The polyester-based elastomer 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 an alkylene group with 2 to 8 carbon atoms. When the polyester-based elastomer contains the above raw material monomers, better mechanical strength tends to be obtained. The polyester-based elastomer is preferably formed by copolymerization of the above two raw material monomers. The copolymerization can be carried out by a known synthesis method.

[0018] 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.

[0019] 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.

[0020] Commercially available biodegradable 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.

[0021] The presence or absence of a polyester elastomer in the molding material or molded article can be determined by the following physical property analysis and component analysis.

[0022] 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.

[0023] 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.

[0024] 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.

[0025] The content of biodegradable polyesters other than polylactic acid is preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 10% by mass or more, particularly preferably 15% by mass or more, and even more particularly preferably 20% by mass or more, based on the total mass of the molding material. The content of aliphatic polyesters is preferably 90% by mass or less, more preferably 70% by mass or less, even more preferably 50% by mass or less, and particularly preferably 40% by mass or less, based on the total mass of the molding material. When the content of aliphatic polyesters is within the above range, better mechanical strength tends to be obtained.

[0026] 1.1.2. Biodegradable resin content and molecular weight In the molding material according to this embodiment, the content of biodegradable resin is preferably 50% by mass or less, more preferably 40% by mass or less, and even more preferably 35% by mass or less, based on the total mass of the material.

[0027] When the content of the biodegradable resin is within this range, the inclusion of the first cellulose and the second cellulose suppresses heat generation during kneading, and the effect of obtaining a molded product with excellent color matching is more pronounced.

[0028] Furthermore, the molecular weight of the polylactic acid and biodegradable polyester other than polylactic acid contained in the biodegradable resin is not particularly limited and is, for example, from 1,000 to 1,000,000. The molding material of this embodiment exhibits excellent appearance and color adjustment properties without being strongly dependent on the molecular weight of the polylactic acid and biodegradable polyester other than polylactic acid contained in the resin.

[0029] 1.2.Cellulose The molding material according to this embodiment contains cellulose, which functions as a filler in the molded article, contributing to increasing the bulk of the molding material and improving the physical properties of the molded article, such as strength.

[0030] Cellulose is derived from plants and is a relatively abundant natural material. Therefore, using cellulose promotes a reduction in the environmental impact compared to using synthetic fibers. Cellulose fibers are also advantageous in terms of raw material procurement and cost. Furthermore, among various fibers, cellulose has a high theoretical strength, which 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 cellulose may also be used.

[0031] Although cellulose is primarily composed of cellulose, it may contain components other than cellulose, such as hemicellulose and lignin. Cellulose fibers may also be subjected to bleaching or other treatments.

[0032] The cellulose used in the molding material of this embodiment includes a first cellulose having a peak top in the particle size range of 3 μm or more and 100 μm or less in a volume-based particle size distribution curve, and a second cellulose having a peak top in the particle size range of 50 μm or more and 500 μm or less in a volume-based particle size distribution curve, and the particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose.

[0033] In this specification, the particle size distribution curve of cellulose is, for example, a volume-based particle size distribution curve measured with a particle size distribution analyzer using a laser diffraction / scattering method. The particle size distribution curve can be displayed as a frequency distribution curve with particle size on the horizontal axis and frequency (unit: %) on the vertical axis, or as an integrated distribution curve with particle size on the horizontal axis and integrated frequency (unit: %) on the vertical axis. Examples of laser diffraction / scattering particle size distribution analyzers that can be used include the "LA-500" manufactured by Horiba, Ltd. and the "SALD-2200" manufactured by Shimadzu Corporation.

[0034] Furthermore, when the average particle size of cellulose is 50 μm or more and 7500 μm or less, the particle size distribution curve of cellulose can be determined, for example, using a Fiber Tester Plus (manufactured by L&W) by placing 300 mL of cellulose dispersion containing 0.1% by mass of sample in the apparatus and measuring. When the average particle size of cellulose is 3 μm or more and 100 μm or less, the particle size distribution curve can be determined, for example, using a flow image analysis method (Seishin Enterprise PITA-04) by placing 50 mL of cellulose dispersion containing 0.05% to 0.1% by mass of sample in the apparatus and measuring. Alternatively, when the average particle size of cellulose is 3 μm or more and 500 μm or less, the particle size distribution curve can be determined, for example, using a scanning electron microscope (Hitachi High-Tech S-4700) by calibrating the ruler in the electron microscope using a calibration standard (EM Japan S2009T) and measuring the length of 100 randomly selected cellulose particles. Furthermore, when the average particle size of cellulose is 0.02 μm or more and 2000 μm or less, it may be determined by using, for example, a laser diffraction particle size distribution analyzer MT3300EXII (laser diffraction / Mie scattering type) manufactured by Microtrac Corporation, placing 20 mL of a cellulose dispersion adjusted to a sample concentration of 0.05% by mass to 0.1% by mass in the device, and performing measurements.

[0035] The particle size distribution curve of cellulose may be determined by any method similar to those described above, and may also be determined by using a combination of two or more of the above methods.

[0036] The particle size detection range is, for example, from 1 μm to 500 μm, and this range is set to be divided into, for example, 1000 parts, with the relative particle amount converted into volume on the vertical axis and particle size on the horizontal axis, and a particle size distribution curve can be obtained by connecting each plot with a straight line. Furthermore, the particle sizes at which the cumulative frequency of particle sizes on this particle size distribution curve reaches 10%, 50%, and 90% are defined as the D10, D50, and D90 of the particles.

[0037] When the first cellulose is used alone to obtain a volume-based particle size distribution curve, it has a peak top in the particle size range of 3 μm to 100 μm. The second cellulose has a peak top in the particle size range of 50 μm to 500 μm. The particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose.

[0038] The peak top in a particle size distribution curve refers to the particle size at the maximum when the particle size distribution curve is displayed as a frequency distribution curve. The peak top in a particle size distribution curve may also be the particle size at the inflection point when the particle size distribution curve is displayed as an integrated distribution curve. Furthermore, the peak top in a particle size distribution curve may be detected by displaying the particle size distribution curve as a frequency distribution curve, regarding it as a linear function, and detecting the position where the slope becomes 0 when differentiated as the peak top or peak bottom.

[0039] Since the molding material of this embodiment contains the first cellulose and the second cellulose, the volumetric particle size distribution curve of the mixture of the first cellulose and the second cellulose shows a bimodal distribution, where the peak top on the smaller particle size side is due to the first cellulose and the peak top on the larger particle size side is due to the second cellulose.

[0040] Furthermore, the peak top particle size of the first cellulose is preferably 5% to 40% of the peak top particle size of the second cellulose, more preferably 7% to 35% and even more preferably 10% to 30%. This further suppresses heat generation during kneading, and more significantly achieves the effect of obtaining a molded product with excellent color matching. Furthermore, this allows the volume-based particle size distribution curve of the mixture of the first cellulose and the second cellulose to show a clearer two-peak distribution.

[0041] The particle size distribution curve of the first cellulose or the second cellulose alone can be obtained by a standard method using a laser diffraction / scattering particle size distribution analyzer. The volume-based particle size distribution curve of a mixture of the first cellulose and the second cellulose can be obtained by a standard method as well, provided that the curve is obtained before the molding material is kneaded. Measurements can also be made after the molding material is kneaded or after a molded body is formed by extracting the resin as needed. Furthermore, the volume-based particle size distribution curve after the molding material is kneaded or after a molded body is formed can be determined using a microscope, image analysis, or the like.

[0042] The cellulose content is preferably 45% by mass or more, more preferably 50% by mass or more, even more preferably 55% by mass or more, even more preferably 60% by mass or more, and particularly preferably 65% ​​by mass or more, relative to the total mass of the molding material. Furthermore, the cellulose content is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 70% by mass or less, relative to the total mass of the molding material. When the cellulose fiber content is within the above range, good mechanical strength tends to be obtained. Furthermore, since the molding material of this embodiment contains the first cellulose and the second cellulose, even with such a high cellulose content, heat generation during kneading and molding is suppressed, and a molded product with excellent color tone can be obtained.

[0043] 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").

[0044] 1.3.Other Ingredients The molding material of this embodiment may further contain a filler. The filler may be either an inorganic filler or an organic filler. Examples of inorganic fillers include talc, titanium oxide, calcium carbonate, carbon black, titanium dioxide-coated mica, fish scale foil, bismuth oxychloride, and particles of aluminum, silver, gold, platinum, nickel, chromium, tin, zinc, indium, titanium, copper, and the like, either as a single element or as an alloy. These inorganic fillers may be classified as pigments.

[0045] Examples of organic fillers include azo pigments such as insoluble azo pigments, condensed azo pigments, azo lakes, and chelate azo pigments; polycyclic pigments such as phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxane pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments; dye chelates, dye lakes, nitro pigments, nitroso pigments, aniline black, and daylight fluorescent pigments.

[0046] When the molding material contains a filler, molded articles with better impact resistance may be obtained, and when the molding material contains a pigment, molded articles with better appearance and color tone may be obtained.

[0047] 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.

[0048] 1.4.Physical properties etc. 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.

[0049] 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%.

[0050] 1.5. Effects and Mechanisms This molding material, containing a first cellulose and a second cellulose, suppresses heat generation during kneading, enabling the production of molded articles with excellent toning properties. The coexistence of a second cellulose with a large average particle size and a first cellulose with a small average particle size allows the first cellulose to exist in the gaps between the multiple second celluloses. This suppresses viscosity increases even when the cellulose content is high, for example, at 40% by mass or more, making the material suitable for injection molding. This also suppresses heat generation during kneading, thereby preventing cellulose from burning and improving toning properties.

[0051] Furthermore, since a biodegradable resin is used, the molded article can be made biodegradable. Furthermore, by using polylactic acid in combination with a polyester other than polylactic acid, a molded article with excellent mechanical properties can be obtained.

[0052] 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.

[0053] First, the raw materials (each component of the molding material) are kneaded in a single-screw or twin-screw kneader to form a strand, which is then pelletized to form pellets of the molding material.

[0054] 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, cellulose and a resin containing polylactic acid and a biodegradable polyester other than polylactic acid are weighed and kneaded. Next, the kneaded raw materials are deposited in air to form a sheet-like deposit. Since the deposit contains a lot 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.

[0055] 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.

[0056] 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.

[0057] 3. Molded products A molded article according to one embodiment of the present invention is molded using the molding material described above.

[0058] By using the molding material described above, the molded article according to this embodiment can be made to have biodegradability, excellent mechanical strength, and excellent color-tuning properties.

[0059] The molded article according to the present embodiment is preferably a container or tableware. Although such molded articles are more likely to be inappropriately disposed of by consumers in the natural environment, the molded article according to the present embodiment is biodegradable and has excellent color-tuning properties, thereby reducing the possibility of inappropriate disposal.

[0060] The container is not particularly limited, and examples thereof include food containers, agricultural and horticultural containers, blister pack containers, press-through pack containers, and fluid containers.

[0061] Examples of food containers include fresh food trays, instant food containers, fast food containers, lunch boxes, and beverage containers. Examples of agricultural and horticultural containers include seedling pots. Examples of blister pack containers include packaging and packing containers for a variety of products for machinery and industrial use, such as office supplies, toys, and dry batteries, in addition to food. Examples of liquid containers include ink cartridge exteriors and cosmetic containers.

[0062] The tableware is not particularly limited, and examples thereof include plates, bowls, bowls, chopsticks, spoons, forks, knives, etc.

[0063] 4. Examples and Comparative Examples 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.

[0064] 4.1. 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.

[0065] 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.

[0066] 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.

[0067] 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) Polylactic acid: Unitika Terramac TE-2000 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)

[0068] In Table 2, "X" in the evaluation of complex viscosity indicates that kneading was impossible.

[0069] 4.2.Evaluation Test 4.2.1. Complex viscosity and injection moldability evaluation 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

[0070] 4.2.2. Evaluation of appearance and color matching For the evaluation samples according to the examples and comparative examples obtained above, the L* value was measured using a fluorescence spectrodensitometer (FD-7, manufactured by Konica Minolta, Inc.), and was evaluated according to the following criteria. (Judgment criteria) A:L * is 70 or more B:L * is less than 70

[0071] 4.2.3. Evaluation of Charpy impact strength For the evaluation samples according to the examples and comparative examples obtained above, the test pieces were rectangular plates with long sides of 80 mm±2 mm, short sides of 4.0 mm±0.2 mm, and a thickness of 10.0 mm±0.2 mm. The Charpy impact strength was measured in accordance with ISO 179 (JIS K7111) using an "Impact Tester IT" manufactured by Toyo Seiki Seisaku-sho as the testing device, 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 45°.

[0072] 4.2.4. Verification The above evaluation was judged according to the following criteria, and the molding materials of each example were evaluated. A: Injection moldability and appearance / color matching are all A, and the Charpy impact strength is 4kJ / m 2 That's all. B: Injection moldability and appearance / color matching are all A, and the Charpy impact strength is 4kJ / m 2 is less than. C: Appearance and color matching are B. D: Unable to knead.

[0073] 4.3.Evaluation of Results It was found that the molding materials of each example, which contain cellulose, polylactic acid, and a biodegradable polyester other than polylactic acid, and which include a first cellulose having a peak top in the particle size range of 3 μm to 100 μm in a volume-based particle size distribution curve, and a second cellulose having a peak top in the particle size range of 50 μm to 500 μm in a volume-based particle size distribution curve, and in which the particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose, all have good color toning properties and good overall evaluations.

[0074] The above-described embodiment is merely an example, and the present invention is not limited to this. For example, the embodiments and modifications can be combined as appropriate.

[0075] The present invention includes configurations that are substantially the same as the configurations described in the embodiments, for example, configurations with the same functions, methods, and results, or configurations with the same purpose and effects. The present invention also includes configurations that replace non-essential parts of the configurations described in the embodiments. 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 that add publicly known technology to the configurations described in the embodiments.

[0076] The following can be derived from the above-described embodiment and modifications.

[0077] The molding material is A molding material comprising a biodegradable resin and cellulose, the biodegradable resin includes polylactic acid and a biodegradable polyester other than polylactic acid; The cellulose is a first cellulose having a peak top in a particle size range of 3 μm or more and 100 μm or less in a volume-based particle size distribution curve; a second cellulose having a peak top in a particle size range of 50 μm or more and 500 μm or less in a volume-based particle size distribution curve; Including, The particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose.

[0078] According to this molding material, since it contains the first cellulose and the second cellulose, heat generation during kneading is suppressed, and a molded product with excellent color-tuning properties can be obtained.

[0079] In the molding material, The complex viscosity may be 600 Pa·s or more and 80,000 Pa·s or less.

[0080] This molding material further suppresses heat generation during kneading, and allows molded products to be obtained with good moldability.

[0081] In the molding material, It may further contain a filler.

[0082] This molding material allows for the production of molded articles with better impact resistance.

[0083] In the molding material, The content of the biodegradable resin may be 50% by mass or less based on the total mass of the material.

[0084] According to this molding material, by including the first cellulose and the second cellulose, heat generation during kneading is suppressed, and the effect of being able to obtain a molded product with excellent color-tuning ability is more significantly achieved.

[0085] In the molding material, The particle size at the peak top of the first cellulose may be 5% or more and 40% or less of the particle size at the peak top of the second cellulose.

[0086] This molding material suppresses heat generation during kneading, and more significantly achieves the effect of obtaining a molded product with excellent color-matching properties.

[0087] In the molding material, The cellulose content may be 60% by mass or more.

[0088] This molding material suppresses heat generation during kneading, and more significantly achieves the effect of obtaining a molded product with excellent color-matching properties.

[0089] One embodiment of the molded article is The molding material is molded using any one of the above-described molding materials.

[0090] In one embodiment of the molded article, The molded article may be a container or tableware.

Claims

1. A molding material comprising a biodegradable resin and cellulose, the biodegradable resin includes polylactic acid and a biodegradable polyester other than polylactic acid; The cellulose is a first cellulose having a peak top in a particle size region of 3 μm or more and 100 μm or less in a volume-based particle size distribution curve; a second cellulose having a particle size peak top in a region of 50 μm or more and 500 μm or less in a volume-based particle size distribution curve; Including, A molding material, wherein the particle size at the peak top of the first cellulose is smaller than the particle size at the peak top of the second cellulose.

2. In claim 1, A molding material having a complex viscosity of 600 Pa·s or more and 80,000 Pa·s or less.

3. In claim 1, The molding material further comprises a filler.

4. In claim 1, A molding material, wherein the content of the biodegradable resin is 50% by mass or less based on the total mass of the material.

5. In claim 1, A molding material, wherein the particle size at the peak top of the first cellulose is 5% or more and 40% or less of the particle size at the peak top of the second cellulose.

6. In claim 1, A molding material having a cellulose content of 60% by mass or more.

7. A molded product molded using the molding material according to claim 1.

8. The molded article according to claim 7, wherein the molded article is a container or tableware.

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