Resin composition and resin molded article

Abstract

To provide a resin composition that yields resin molded articles with excellent long-term resistance to ozone degradation. [Solution] A resin composition comprising a polyester resin containing an amorphous polyester resin, wax, silica particles with an average particle size of 50 nm to 80 nm, a core material containing magnetic powder, and a coating resin layer covering the core material, comprising magnetic particles with an average particle size of 30 μm to 80 μm, flat inorganic particles with an average major diameter of 5 μm to 10 μm, and a thermoplastic resin other than the amorphous polyester resin.

Description

Technical Field

[0001] The present invention relates to a resin composition and a resin molded body.

Background Art

[0002] Conventionally, various resin compositions have been provided and used for various applications. In particular, resin molded bodies using resin compositions containing thermoplastic resins are used for various parts (for example, housings, etc.) of office equipment, household appliances, automobiles, and the like.

[0003] For example, Patent Document 1 discloses "a resin composition containing a resin physical property improver containing talc powder."

[0004] Further, Patent Document 2 discloses "a thermally conductive resin composition comprising a thermally conductive filler and a binder resin."

[0005] Further, Patent Document 3 discloses "a container having a bottom portion, a peripheral wall portion extending upward from the outer peripheral edge of the bottom portion, and a flange portion extending outward from the peripheral wall portion, wherein the remaining portion excluding the flange portion and the upper end portion of the peripheral wall portion is composed of a core portion made of a first thermoplastic resin containing at least one polyolefin-based resin and 0.01 to 3.0% by weight of a chlorine-containing resin, and a skin layer made of a second thermoplastic resin covering the core portion, while the flange portion and the upper end portion of the peripheral wall portion are composed of the second thermoplastic resin, and the first thermoplastic resin is a container packaging recyclable material."

[0006] Further, Patent Document 4 discloses "a resin composition containing plate-like thermally conductive particles, spherical thermally conductive particles, and a resin."

[0007] Regarding toner, for example, Patent Document 5 discloses "an electrophotographic toner containing flat microparticles."

Prior Art Documents

[0008] [Patent Document 1] Patent No. 7320802 [Patent Document 2] International Public Gazette No. 2013 / 100174 [Patent Document 3] Patent No. 5835982 [Patent Document 4] Patent No. 6460365 [Patent Document 5] Japanese Patent Application Publication No. 5-119515 [Overview of the project] [Problems that the invention aims to solve]

[0009] The object of the present invention is to provide a resin composition that yields a resin molded article with superior long-term ozone degradation resistance compared to a resin composition comprising a polyester resin, wax, silica particles with an average particle size of 50 nm to 80 nm, a core material containing magnetic powder, and a coating resin layer covering the core material, and comprising magnetic particles with an average particle size of 30 μm to 80 μm, flat inorganic particles with an average major diameter of less than 5 μm, and a thermoplastic resin other than polyester resin. [Means for solving the problem]

[0010] The means for solving the above problems include the following embodiments. <1> Polyester resin containing amorphous polyester resin, wax and, Silica particles with an average particle size of 50 nm to 80 nm, A core material containing magnetic powder, and a coating resin layer covering the core material, comprising magnetic particles with an average particle size of 30 μm or more and 80 μm or less, Flattened inorganic particles with an average major diameter of 5 μm or more and 10 μm or less, Thermoplastic resins other than the aforementioned polyester resin, A resin composition containing the following: <2> The average aspect ratio of the flattened inorganic particles is between 5 and 100. <1> A resin composition. <3> The average aspect ratio of the flattened inorganic particles is 5 or more and 50 or less. <2> A resin composition. <4> The ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 69 or more and 176 or less. <1> ~ <3> A resin composition according to any one of the following items. <5> The ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 73 or more and 110 or less. <4> A resin composition. <6> The ratio of the average major axis of the flattened inorganic particles to the average particle size of the magnetic particles is 0.069 or more and 0.176 or less. <1> ~ <5> A resin composition according to any one of the following items. <7> The polyester resin content is 1.5 parts by mass or more and 52 parts by mass or less per 100 parts by mass of the thermoplastic resin. The wax content is 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The silica particle content is 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The content of the magnetic particles is 0.3 parts by mass or more and 10.3 parts by mass or less per 100 parts by mass of the thermoplastic resin. The content of the flattened inorganic particles is 0.3 parts by mass or more and 160 parts by mass or less per 100 parts by mass of the thermoplastic resin. <1> ~ <6> A resin composition according to any one of the following items. <8> The content of the flattened inorganic particles relative to the silica particles is 90% by mass or more and 5400% by mass or less. The content of the flattened inorganic particles relative to the magnetic particles is 23% by mass or more and 1350% by mass or less. <1> ~ <7> A resin composition according to any one of the following items. <9> <1> ~ <8> A resin molded article comprising the resin composition described in any one of the items. <10> A method for producing a resin composition according to any one of <1> to <8>, comprising kneading a composition containing particles including the polyester resin and the wax, the silica particles, and the magnetic particles, and the flat inorganic particles, and then kneading the obtained kneaded product and the thermoplastic resin to obtain a resin composition.

Advantages of the Invention

[0011] According to the invention according to <1>, compared with a resin composition containing a polyester resin, a wax, silica particles having an average particle size of 50 nm or more and 80 nm or less, a core material containing magnetic powder, and a coating resin layer coating the core material, magnetic particles having an average particle size of 30 μm or more and 80 μm or less, flat inorganic particles having an average major axis length of less than 5 μm, and a thermoplastic resin other than the polyester resin, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. According to the invention according to <2>, compared with the case where the average aspect ratio of the flat inorganic particles is less than 5 or more than 100, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. According to the invention according to <3>, compared with the case where the average aspect ratio of the flat inorganic particles is less than 5 or more than 50, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. According to the invention according to <4>, compared with the case where the ratio of the average major axis length of the flat inorganic particles to the average particle size of the silica particles is less than 69 or more than 176, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. According to the invention according to <5>, compared with the case where the ratio of the average major axis length of the flat inorganic particles to the average particle size of the silica particles is less than 73 or more than 110, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. According to the invention according to <6>, compared with the case where the ratio of the average major axis length of the flat inorganic particles to the average particle size of the magnetic particles is less than 0.069 or more than 0.176, a resin composition capable of obtaining a resin molded body excellent in long-term ozone degradation resistance is provided. <7> According to the invention, a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to a case where the content of any of the components in the thermoplastic resin does not meet the above range. <8> According to the invention, a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to the case where the content of flattened inorganic particles relative to silica particles or magnetic particles does not meet the above range.

[0012] <9> According to the present invention, a resin molded article is provided that has superior long-term ozone degradation resistance compared to a resin molded article to which a resin composition is applied, comprising a polyester resin, wax, silica particles with an average particle size of 50 nm to 80 nm, a core material containing magnetic powder, and a coating resin layer covering the core material, wherein the resin molded article is to which a resin composition comprising magnetic particles with an average particle size of 30 μm to 80 μm, flat inorganic particles with an average major diameter of less than 5 μm, and a thermoplastic resin other than polyester resin is applied.

[0013] <10> According to the invention, compared to a method for producing a resin composition in which a resin composition is obtained by kneading a composition containing particles containing polyester resin and wax, silica particles with an average particle size of 50 nm to 80 nm, and magnetic particles, and flat inorganic particles with an average major diameter of less than 5 μm, and then kneading the resulting kneaded product with a thermoplastic resin, a method for producing a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance. [Modes for carrying out the invention]

[0014] The following describes an example of the present invention. These descriptions and examples are illustrative and do not limit the scope of the embodiments.

[0015] In this specification, numerical ranges indicated using "~" represent a range that includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described in stages, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, within a numerical range, the upper or lower limit of that range may be replaced with the values ​​shown in the examples. The term "process" includes not only independent processes, but also any process that cannot be clearly distinguished from other processes, as long as its purpose is achieved. Each component may contain multiple types of the corresponding substance. When referring to the amount of each component in a composition in this disclosure, if there are multiple types of the substance corresponding to each component in the composition, unless otherwise specified, it means the total amount of those multiple types of substances present in the composition. Each component may contain multiple types of particles. If multiple types of particles corresponding to each component are present in the composition, the particle size of each component refers to the value for a mixture of such multiple types of particles present in the composition, unless otherwise specified.

[0016] "Aspect ratio" is the ratio of the major axis to the minor axis (major axis / minor axis). The "major axis" is the length of the longest straight line connecting any two points on the contour line of the object being measured, as observed during the measurement process. The "minor axis" is the length of the longest straight line that is perpendicular to the straight line forming the major axis and connects the contour lines of two opposing objects being measured.

[0017] <Resin composition> The resin composition according to this embodiment includes a polyester resin (P), a wax (W), silica particles (S), magnetic particles (M), flattened inorganic particles (F), and a thermoplastic resin other than an amorphous polyester resin (T). Polyester resin (P) includes amorphous polyester resin. Silica particles (S) are silica particles with an average particle size of 50 nm to 80 nm. The magnetic particles (M) consist of a core material containing magnetic powder and a coating resin layer covering the core material, and have an average particle size of 30 μm or more and 80 μm or less. The flattened inorganic particles (F) are flattened inorganic particles with an average major axis of 5 μm or more and 10 μm or less. A resin composition containing the following:

[0018] Here, the resin composition according to this embodiment is a raw material for obtaining a resin molded article. The resin composition according to this embodiment includes pellets or a masterbatch having the same component ratio as the resin molded article to be molded. A masterbatch is, for example, a composition for obtaining pellets with the same component ratio as the resin molded article to be molded, or a composition for molding a resin molded article by kneading it with a thermoplastic resin (T) during the molding process. Therefore, a masterbatch is a composition in which the thermoplastic resin (T) content is lower than that of pellets (i.e., the resin molded product) with the same component ratio as the resin molded product to be molded. Thus, the resin composition according to this embodiment, when in the form of pellets, is a composition containing thermoplastic resin (T), while when in the form of a masterbatch, it also includes compositions with a very small amount of thermoplastic resin (T).

[0019] The resin composition according to this embodiment yields a resin molded article with excellent long-term ozone degradation resistance. The reason for this is presumed to be as follows.

[0020] Conventionally, resin molded articles using resin compositions containing thermoplastic resins are used in various parts (e.g., housings) of office equipment, home appliances, automobiles, etc. Therefore, techniques for incorporating various fillers into resin molded articles to increase their mechanical strength are known. On the other hand, resin molded products used in components such as office equipment require long-term resistance to ozone degradation. In order to impart ozone degradation resistance, it is advisable to incorporate wax into the resin molded body. This is because the wax seeps onto the surface of the resin molded body and acts as a protective film against ozone. However, wax has low affinity for thermoplastic resins (T) other than polyester resin, and quickly seeps out onto the surface of the molded resin. Therefore, it is difficult to impart ozone degradation resistance over the long term.

[0021] Therefore, the resin composition according to this embodiment has the composition described above. The resin molded article obtained using this resin composition has magnetic particles (M) coated with a resin layer, and therefore the magnetic particles (M) are well dispersed within the thermoplastic resin (T). In the resin molded body, a structure (a so-called stone wall structure) is formed in which flat inorganic particles (F) of intermediate diameter are arranged between magnetic particles (M) of the largest diameter, and silica particles (S) of the smallest diameter are arranged between the flat inorganic particles (F). This stone wall structure creates appropriate voids between each particle, along with the free volume of the resin. As a result, the slow release of wax (W) is controlled, and the seepage of wax (W) is appropriate. In addition, by incorporating polyester resin (P), which has a greater affinity for wax (W) compared to thermoplastic resins (T) other than polyester resin (P), the sustained release of wax (W) is controlled, resulting in an appropriate amount of wax (W) seepage. In other words, wax (W) will continue to seep out onto the surface of the resin molded product over a long period of time.

[0022] From the above, it is presumed that the resin composition according to this embodiment will yield a resin molded article with excellent long-term resistance to ozone degradation.

[0023] In the resin composition according to this embodiment, the polyester resin (P), wax (W), and silica particles (S) can be components contained in discarded electrostatic image developing toner (hereinafter referred to as "waste toner"). Specifically, the raw materials for the resin composition can be waste toner containing toner particles with polyester resin (P) and wax (W) and an external additive with silica particles (S). For the magnetic particles (M), discarded electrostatic image developing carriers (hereinafter referred to as "waste carriers") can be used. For thermoplastic resin (T), recycled thermoplastic resin can be used. Therefore, the resin composition according to this embodiment can be obtained by utilizing recovered resources while reducing factory waste. As a result, the resulting resin molded article is low-cost and suitable for the requirements of the SDGs (Sustainable Development Goals).

[0024] In the resin composition according to this embodiment, a stone wall structure is formed by each particle in the resulting resin molded article. Therefore, in the resin composition according to this embodiment, the stone wall structure packs the spaces between large-diameter magnetic particles (M) with small-diameter silica particles (S), and further surrounds them with flattened inorganic particles (F), resulting in a dense structure. Furthermore, although large-diameter magnetic particles (M) and small-diameter silica particles (S) are prone to crazing when impact is propagated, the flattened inorganic particles (F) prevent crazing, thereby enhancing impact resistance. Thus, a resin molded article with both high strength and impact resistance is obtained from the densely packed structure, resulting in a resin molded article with excellent impact resistance.

[0025] In the resin composition according to this embodiment, the magnetic particles (M) with the largest diameter are well dispersed in the resulting resin molded article. Therefore, in the resin composition according to this embodiment, the filling effect by the magnetic particles (M) is enhanced, and a resin molded article with excellent elastic modulus is obtained.

[0026] In the resin composition according to this embodiment, wax (W) seeps out onto the surface of the resulting resin molded article over a long period of time, and the seeped-out wax (W) functions as a protective film. Therefore, the resulting resin molded article exhibits excellent resistance to humidity and heat over a long period of time.

[0027] The resin composition according to this embodiment contains wax (W). As a result, the fluidity is increased by the melting of the wax (W) during molding. Therefore, it also has excellent moldability.

[0028] In this embodiment, the resin composition is compounded with magnetic particles (M) containing magnetic powder into the resulting resin molded article. This imparts electrostatic properties to the resin molded article and improves its stain resistance.

[0029] The resin composition according to this embodiment will now be described in detail.

[0030] (Polyester resin (P)) Polyester resin (P) includes amorphous polyester resin. The amorphous polyester resin content should be 60% to 100% by mass (preferably 70% to 100% by mass) relative to the total polyester resin (P). Here, the polyester resin (P) may include not only amorphous polyester resin but also crystalline polyester resin. However, the content of crystalline polyester resin should preferably be 2% by mass or more and 40% by mass or less (preferably 2% by mass or more and 30% by mass or less) relative to the total polyester resin (P).

[0031] Furthermore, the "crystalline nature" of a resin refers to the presence of a clear endothermic peak rather than a stepwise change in endothermic quantity in differential scanning calorimetry (DSC). Specifically, it means that the full width at half maximum of the endothermic peak measured at a heating rate of 10°C / min is within 10°C. On the other hand, "amorphous" resins refer to those with a full width at half maximum exceeding 10°C, exhibiting a stepwise change in endothermic capacity, or lacking a clear endothermic peak.

[0032] -Amorphous polyester resin- Examples of amorphous polyester resins include condensation polymers of polycarboxylic acids and polyhydric alcohols. The amorphous polyester resin may be a commercially available product or a synthesized one.

[0033] Examples of polycarboxylic acids include aliphatic dicarboxylic acids (e.g., oxalic acid, malonic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, glutaconic acid, succinic acid, alkenyl succinic acids (hexenyl succinic acid, octenyl succinic acid, dodecenyl succinic acid, pentadecenyl succinic acid, etc.), adipic acid, sebacic acid, etc.), alicyclic dicarboxylic acids (e.g., cyclohexanedicarboxylic acid), aromatic dicarboxylic acids (e.g., terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., with 1 to 5 carbon atoms). Among these, aromatic dicarboxylic acids are preferred as polycarboxylic acids. Polycarboxylic acids may be used in combination with dicarboxylic acids, or with trivalent or higher carboxylic acids that have a cross-linked or branched structure. Examples of trivalent or higher carboxylic acids include trimellitic acid, pyromellitic acid, their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). Polycarboxylic acids may be used individually or in combination of two or more.

[0034] Examples of polyhydric alcohols include aliphatic diols (e.g., ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, butanediol, hexanediol, neopentyl glycol, etc.), alicyclic diols (e.g., cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, etc.), and aromatic diols (e.g., ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, etc.). Among these, aromatic diols and alicyclic diols are preferred as polyhydric alcohols, and aromatic diols are more preferred. As for the polyhydric alcohol, a trihydric or higher polyhydric alcohol with a cross-linked or branched structure may be used in combination with the diol. Examples of trihydric or higher polyhydric alcohols include glycerin, trimethylolpropane, and pentaerythritol. Polyhydric alcohols may be used individually or in combination of two or more types.

[0035] The glass transition temperature (Tg) of amorphous polyester resin is preferably 50°C to 80°C, and more preferably 50°C to 65°C. The glass transition temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC), and more specifically, it is determined by the "extracorporeal glass transition onset temperature" described in the method for determining the glass transition temperature in JIS K 7121-1987 "Method for Measuring the Transition Temperature of Plastics".

[0036] The weight-average molecular weight (Mw) of the amorphous polyester resin is preferably 5,000 to 1,000,000, and more preferably 7,000 to 500,000. The number-average molecular weight (Mn) of the amorphous polyester resin is preferably between 2,000 and 100,000. The molecular weight distribution (Mw / Mn) of the amorphous polyester resin is preferably 1.5 to 100, and more preferably 2 to 60. The weight-average molecular weight and number-average molecular weight are measured by gel permeation chromatography (GPC). GPC molecular weight measurement is performed using a Tosoh GPC-HLC-8320GPC analyzer, a Tosoh TSKgel SuperHM-M (15cm) column, and THF solvent. The weight-average molecular weight and number-average molecular weight are calculated from these measurement results using a molecular weight calibration curve prepared with monodisperse polystyrene standard samples.

[0037] Amorphous polyester resins may be used individually or in combination of two or more types. When using two or more types in combination, for example, a high molecular weight resin and a low molecular weight resin may be used together.

[0038] Amorphous polyester resins can be obtained by well-known manufacturing methods. Specifically, for example, they can be obtained by a method in which the polymerization temperature is set to 180°C or higher and 230°C or lower, and the reaction system is subjected to reduced pressure as needed, while removing water and alcohol generated during condensation. If the monomers of the raw materials do not dissolve or become miscible at the reaction temperature, a high-boiling point solvent may be added as a solubilizer to dissolve them. In this case, the polycondensation reaction should be carried out while distilling off the solubilizer. If there are monomers with poor miscibility, it is advisable to condense the poorly miscible monomers with the acid or alcohol to be polycondensed with them beforehand, and then polycondense them together with the main component.

[0039] -Crystalline polyester resin- Crystalline polyester resins include, for example, polycondensates of polycarboxylic acids and polyhydric alcohols. Commercially available crystalline polyester resins may be used, or synthesized resins may be used. Here, in order to easily form a crystalline structure, polycondensates using polymerizable monomers having linear aliphatic structures are preferred over polymerizable monomers having aromatic structures.

[0040] Examples of polycarboxylic acids include aliphatic dicarboxylic acids (e.g., oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, 1,9-nonanedicarboxylic acid, 1,10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid, 1,14-tetradecanedicarboxylic acid, 1,18-octadecanedicarboxylic acid, etc.), aromatic dicarboxylic acids (e.g., phthalic acid, isophthalic acid, terephthalic acid, dibasic acids such as naphthalene-2,6-dicarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). Polycarboxylic acids may be used in combination with dicarboxylic acids, or with trivalent or higher carboxylic acids that have a crosslinked or branched structure. Examples of trivalent carboxylic acids include aromatic carboxylic acids (e.g., 1,2,3-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, 1,2,4-naphthalentricarboxylic acid, etc.), their anhydrides, or their lower alkyl esters (e.g., having 1 to 5 carbon atoms). In addition to these dicarboxylic acids, polycarboxylic acids with sulfonic acid groups and dicarboxylic acids with ethylenic double bonds may also be used in combination. Polycarboxylic acids may be used individually or in combination of two or more.

[0041] Examples of polyhydric alcohols include aliphatic diols (for example, linear aliphatic diols in which the main chain has 2 to 20 carbon atoms). Examples of aliphatic diols include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,18-octadecanediol, and 1,1,20-eicosanediol. Among these, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, and 1,10-decanediol are preferred as aliphatic diols. Polyhydric alcohols may be used in combination with diols, including trihydric or higher alcohols that have a cross-linked or branched structure. Examples of trihydric or higher alcohols include glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol. Polyhydric alcohols may be used individually or in combination of two or more types.

[0042] Here, the polyhydric alcohol is preferably composed of 80 mol% or more of aliphatic diols, and more preferably 90 mol% or more.

[0043] The melting temperature of the crystalline polyester resin is preferably 50°C to 100°C, more preferably 55°C to 90°C, and even more preferably 60°C to 85°C. The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) using the "melting peak temperature" described in JIS K7121-1987 "Method for determining the transition temperature of plastics".

[0044] The weight-average molecular weight (Mw) of the crystalline polyester resin is preferably between 6,000 and 50,000.

[0045] Crystalline polyester resins can be obtained, for example, by well-known manufacturing methods, similar to amorphous polyesters.

[0046] Furthermore, the polyester resin (P) may be a hybrid resin having a polyester resin segment and a styrene-acrylic copolymer segment.

[0047] (Wax (W)) Examples of waxes (W) include hydrocarbon waxes; natural waxes such as carnauba wax, rice wax, and candelilla wax; synthetic or mineral / petroleum-based waxes such as montan wax; and ester waxes such as fatty acid esters and montanic acid esters. However, waxes (W) are not limited to these.

[0048] The melting temperature of the wax (W) is preferably 50°C to 110°C, and more preferably 60°C to 100°C. The melting temperature is determined from the DSC curve obtained by differential scanning calorimetry (DSC) using the "melting peak temperature" described in JIS K 7121-1987 "Method for determining the transition temperature of plastics".

[0049] (Silica particles (S)) Silica particles (S) refer to silica particles with an average particle size of 50 nm to 80 nm. When the average particle size of the silica particles (S) is within the above range, the function of the stone wall structure with magnetic particles (M) and flattened inorganic particles (F) is more easily achieved. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term resistance to moisture and heat. In particular, impact resistance tends to decrease when the average particle size of silica particles (S) is less than 50 nm. Furthermore, if the average particle size of silica particles (S) exceeds 80 nm, the surface resistivity decreases, resulting in poor stain resistance. Therefore, the average particle size of the silica particles (S) shall be between 50 nm and 80 nm. The average particle size of the silica particles (S) is more preferably between 60 nm and 80 nm.

[0050] The average particle size of silica particles (S) is measured as follows: A sample taken from a resin composition or resin molded body is embedded in epoxy resin, then cut with a microtome to obtain an observation sample with a cross-sectional surface. A scanning electron microscope (SEM) is used to photograph the cross-section of the sample and obtain an SEM image. The obtained SEM image is then imported into an image processing and analysis system for image analysis. From the SEM images after image analysis, 100 primary silica particles (S) are randomly selected, and their equivalent circle diameter (nm) is determined. The obtained equivalent circle diameters are arithmetic mean, and this arithmetic mean is taken as the average particle size (nm) of the silica particles (S).

[0051] The silica particles (S) are preferably spherical. Specifically, the average aspect ratio of the silica particles (S) is preferably 1 or more and less than 5, and preferably 1 or more and 3 or less. When the silica particles (S) are spherical, the stone wall structure function with the magnetic particles (M) and flattened inorganic particles (F) is more easily achieved. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term resistance to moisture and heat.

[0052] The average aspect ratio of silica particles (S) is measured as follows: A sample taken from a resin composition or resin molded body is embedded in epoxy resin, then cut with a microtome to obtain an observation sample with a cross-sectional surface. A scanning electron microscope (SEM) is used to photograph the cross-section of the sample and obtain an SEM image. The obtained SEM image is then imported into an image processing and analysis system for image analysis. From the SEM images after image analysis, 100 primary silica particles (S) are randomly selected, their major and minor axes are determined, and their aspect ratios are calculated. The obtained aspect ratios are arithmetically averaged, and this arithmetic mean is taken as the average aspect ratio of the silica particles (S).

[0053] (Magnetic particles (M)) Magnetic particles (M) are defined as magnetic particles with an average particle size of 30 μm or more and 80 μm or less. When the average particle size of the magnetic particles (M) is within the above range, the function of the stone wall structure between the magnetic particles (M) and the flattened inorganic particles (F) is more easily achieved. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term resistance to moisture and heat. In particular, impact resistance tends to decrease when the average particle size of magnetic particles (M) is less than 30 μm. Furthermore, if the average particle size of the magnetic particles (M) exceeds 80 μm, the surface resistivity decreases, resulting in poor stain resistance. Therefore, the average particle size of the magnetic particles (M) shall be between 30 μm and 80 μm.

[0054] The average particle size of magnetic particles (M) is measured using the same method as the average particle size of silica particles (S).

[0055] The magnetic particles (M) are preferably spherical. Specifically, the average aspect ratio of the magnetic particles (M) is preferably 1 or more and less than 5, and preferably 1 or more and 3 or less. When the magnetic particles (M) are spherical, the function of the stone wall structure between the magnetic particles (M) and the flattened inorganic particles (F) is more easily achieved. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term heat and humidity resistance.

[0056] The average aspect ratio of magnetic particles (M) is a value measured in the same way as the average aspect ratio of silica particles (S).

[0057] The magnetic particle (M) comprises a core material containing magnetic powder and a coating resin layer covering the core material.

[0058] Examples of magnetic powders include magnetic metals such as iron, nickel, and cobalt, and magnetic oxides such as ferrite and magnetite. In particular, magnetite and ferrite are preferred as magnetic powders. The magnetic powder may also be used as particles in which the magnetic powder is dispersed in a resin.

[0059] Examples of coating resins and resins for dispersing magnetic powders include: styrene-(meth)acrylic acid resin; polyolefin resins such as polyethylene resin and polypropylene resin; polyvinyl or polyvinylidene resins such as polystyrene, (meth)acrylic resin, polyacrylonitrile, polyvinyl acetate, polyvinyl alcohol, polyvinyl butyral, polyvinyl chloride, polyvinylcarbazole, polyvinyl ether, and polyvinyl ketone; vinyl chloride-vinyl acetate copolymer; straight silicone resins or modified products thereof consisting of organosiloxane bonds; fluororesins such as polytetrafluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, and polychlorotrifluoroethylene; polyester; polyurethane; polycarbonate; amino resins such as urea-formaldehyde resin; epoxy resin; and others. The coating resin and the resin for dispersing the magnetic powder preferably contain a (meth)acrylic resin, and more preferably a (meth)acrylic resin having an alicyclic structure. The coating resin and the resin for dispersing the magnetic powder may also contain a nitrogen-containing (meth)acrylic resin. It is more preferable that the (meth)acrylic resin is present in an amount of 50% by mass or more relative to the total mass of the resin, and even more preferable that the (meth)acrylic resin is present in an amount of 80% by mass or more relative to the total mass of the resin. In particular, the coating resin and the resin for dispersing the magnetic powder preferably include an alicyclic (meth)acrylic resin as the (meth)acrylic resin. Furthermore, the coating resin and the resin in which the magnetic powder is dispersed may contain conductive particles or other additives. Examples of conductive particles include metals such as gold, silver, and copper, as well as carbon black, titanium oxide, zinc oxide, tin oxide, barium sulfate, aluminum borate, and potassium titanate. Other additives include metal oxide particles such as silica, titanium oxide, zinc oxide, and tin oxide; metal compound particles such as barium sulfate, aluminum borate, and potassium titanate; and metal particles such as gold, silver, and copper. Among these, silica particles are preferred. The above particles are preferably contained in an amount of 10% to 60% by mass relative to the total mass of the coating resin layer.

[0060] To coat the surface of the core material with a coating resin, one method is to coat it with a coating layer-forming solution prepared by dissolving the coating resin and, if necessary, various additives in a suitable solvent. The solvent is not particularly limited and should be selected considering the coating resin used, its suitability for coating, etc. Specific resin coating methods include the immersion method, in which the core material is immersed in a coating layer forming solution; the spray method, in which the coating layer forming solution is sprayed onto the surface of the core material; the fluidized bed method, in which the coating layer forming solution is sprayed onto the core material while it is suspended by fluidized air; and the kneader coater method, in which the carrier core material and the coating layer forming solution are mixed in a kneader coater and the solvent is removed.

[0061] (Flat inorganic particles (F)) Flattened inorganic particles (F) refer to flattened inorganic particles with an average major diameter of 5 μm or more and 10 μm or less. When the average particle size of the magnetic particles (M) is within the above range, the function of the stone wall structure between the magnetic particles (M) and the flattened inorganic particles (F) is more easily achieved. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term resistance to moisture and heat. In particular, if the average major axis of the flattened inorganic particles (F) is less than 5 μm, the impact resistance tends to be poor. Furthermore, if the average major axis of the flattened inorganic particles (F) exceeds 10 μm, dispersion problems occur, leading to a decrease in tensile strength and impact resistance. Therefore, the average major axis of the flattened inorganic particles (F) shall be between 5 μm and 10 μm. The major axis of a flattened inorganic particle (F) is the length of the longest straight line connecting any two points on the contour line of the flattened inorganic particle (F) when the particle is observed.

[0062] Here, the ratio of the average major axis of the flattened inorganic particles (F) to the average particle size of the silica particles (S) (average major axis of the flattened inorganic particles (F) / average particle size of the silica particles (S)) is preferably 69 or more and 176 or less, and more preferably 73 or more and 110 or less. When the ratio (average major diameter of flattened inorganic particles (F) / average particle size of silica particles (S)) is within the above range, the above-mentioned stone wall structure is more easily formed in the resulting resin molded article. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term heat and humidity resistance.

[0063] The ratio of the average major axis of the flattened inorganic particles (F) to the average particle size of the magnetic particles (M) (average major axis of the flattened inorganic particles (F) / average particle size of the magnetic particles (M)) is preferably 0.069 or more and 0.176 or less. When the ratio (average major diameter of flattened inorganic particles (F) / average particle size of magnetic particles (M)) is within the above range, the above-mentioned stone wall structure is more easily formed in the resulting resin molded article. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term heat and humidity resistance.

[0064] The average major axis of flattened inorganic particles (F) is measured as follows: A sample taken from a resin composition or resin molded body is embedded in epoxy resin, then cut with a microtome to obtain an observation sample with a cross-sectional surface. A scanning electron microscope (SEM) is used to photograph the cross-section of the sample and obtain an SEM image. The obtained SEM image is then imported into an image processing and analysis system for image analysis. From the SEM images after image analysis, 100 primary particles of flattened inorganic particles (F) are randomly selected, and their major axis (μm), i.e., maximum length, is determined. The obtained major axes are arithmetically averaged, and this arithmetic mean is taken as the average major axis (μm) of the flattened inorganic particles (F).

[0065] The average aspect ratio of the flattened inorganic particles (F) is preferably 5 to 100, preferably 5 to 50, and more preferably 10 to 50. When the average aspect ratio of the flattened inorganic particles (F) is within the above range, the above-mentioned stone wall structure is more easily formed in the resulting resin molded article. As a result, the resulting resin molded article exhibits improved long-term ozone degradation resistance, as well as improved elastic modulus, impact resistance, and long-term heat and humidity resistance.

[0066] The average aspect ratio of flattened inorganic particles (F) is a value measured in the same way as the average aspect ratio of silica particles (S).

[0067] Examples of flattened inorganic particles (F) include talc group clay minerals (talc, pyrophyllite, kerolite, etc.), mica group clay minerals (muscovite, phlogopite, margalite, tetrasilyl mica, teniolite, etc.), smectite group clay minerals (montmorillonite, beidelite, nontronite, saponite, hectorite, souconite, stevensite, etc.), kaolin group clay minerals (kaolin, halloysite, kaolinite, endelite, dickite, nacrite, antigorite, chrysotile, etc.), vermiculite group clay minerals (vermiculite, etc.), chlorite group clay minerals (cuquerite, sudoite, clinochlore, chamosite, nimite, etc.), hydrotalcite, platy barium sulfate, boehmite, and aluminum polyphosphate.

[0068] Among these, talc is preferred from the viewpoint of improving the long-term ozone degradation resistance, elastic modulus, impact resistance, and long-term humidity and heat resistance of the resin molded article, as well as cost.

[0069] (Thermoplastic resin (T)) Examples of thermoplastic resins (T) include polyolefin (PO) resins (polyethylene resin, polypropylene resin, etc.), acrylonitrile butadiene styrene (ABS) resin, ethylene vinyl acetate (EVA) resin, ethylene ethyl acrylate (EEA) resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polyacetal (POM) resin, polycarbonate (PC) resin, polyvinylidene fluoride (PVDF) resin, and acrylonitrile styrene (AS) resin. Among these, polypropylene resin or acrylonitrile butadiene styrene (ABS) resin is preferred from the viewpoint of recyclability, cost, and the mechanical strength of the resin molded product.

[0070] (Other additives) The resin composition according to this embodiment may contain other components in addition to the above-mentioned components. Other components include well-known additives such as flame retardants, flame retardant enhancers, drip inhibitors when heated, plasticizers, antioxidants, mold release agents, lightfastness agents, weathering agents, colorants, pigments, modifiers, antistatic agents, hydrolysis inhibitors, fillers, and reinforcing agents.

[0071] In particular, from the viewpoint of improving the impact resistance and processability (e.g., strand processability) of the resulting resin molded article, the resin composition according to this embodiment may also contain rubber as another component. Examples of rubbers include styrene-ethylene-butylene-styrene (SEBS) block copolymer rubber (hydrogenated styrene-based thermoplastic elastomer), polyisoprene rubber (IR), polybutadiene rubber (BR), styrene-butadiene copolymer rubber (SBR), acrylonitrile butadiene rubber (NBR), chloroprene rubber (CR), butyl rubber (IIR), ethylene-propylene copolymer rubber (EPM); ethylene-propylene-diene copolymer rubber (EPDM), and others. Furthermore, as rubber, a "graft copolymer (B1) obtained by polymerizing a vinyl monomer (b) in the presence of a rubbery polymer (a) consisting of ethylene-α-olefin rubber (a1) and / or hydrogenated conjugated diene rubber (a2), or a rubber-reinforced resin consisting of a mixture of the graft copolymer (B1) and a (co)polymer (B2) of vinyl monomer (b)" as described in Japanese Patent Application Publication No. 2008-266606 can also be applied.

[0072] (Content of each component) In the resin composition according to this embodiment, when the resin composition according to this embodiment is "pellets with the same component ratio as the resin molded article to be molded", the following content is preferable from the viewpoint of improving long-term ozone degradation resistance, elastic modulus, impact resistance, long-term heat and humidity resistance, moldability, and antifouling properties. The content of thermoplastic resin (T) is preferably 30% to 98% by mass relative to the resin composition, and more preferably 30% to 84% by mass. The polyester resin (P) content is preferably 1.5 parts by mass or more and 52 parts by mass or less, and more preferably 3 parts by mass or more and 52 parts by mass or less, per 100 parts by mass of thermoplastic resin (T). The wax (W) content is preferably 0.1 parts by mass or more and 2.6 parts by mass or less, and more preferably 0.5 parts by mass or more and 1.8 parts by mass or less, per 100 parts by mass of thermoplastic resin (T). The silica particle (S) content is preferably 0.1 parts by mass or more and 2.6 parts by mass or less, and more preferably 0.5 parts by mass or more and 1.8 parts by mass or less, per 100 parts by mass of thermoplastic resin (T). The content of magnetic particles (M) is preferably 0.3 parts by mass or more and 10.3 parts by mass or less, and more preferably 0.3 parts by mass or more and 10.3 parts by mass or less, per 100 parts by mass of thermoplastic resin (T). The content of flattened inorganic particles (F) is preferably 0.3 parts by mass or more and 160 parts by mass or less, and more preferably 1 part by mass or more and 140 parts by mass or less, per 100 parts by mass of thermoplastic resin (T). In this embodiment, if the resin composition contains rubber, the rubber content is preferably 1 part by mass or more and 5 parts by mass or less per 100 parts by mass of thermoplastic resin (T).

[0073] The content of each component in the resin composition according to this embodiment is not particularly limited, as long as the amount obtained by adding the thermoplastic resin (T) is equal to the content of the pellets, when the resin composition according to this embodiment is a "masterbatch". In other words, it is preferable that the masterbatch be a composition that, by adding a thermoplastic resin (T), results in "pellets with the same component ratio as the resin molded product to be molded."

[0074] Here, the content of flattened inorganic particles (F) is preferably as follows, from the viewpoint of improving long-term ozone degradation resistance, elastic modulus, impact resistance, long-term heat and humidity resistance, moldability, and antifouling properties, regardless of whether the resin composition according to this embodiment is a "pellet with the same component ratio as the resin molded article to be molded" or a "masterbatch". The content of flattened inorganic particles (F) relative to silica particles (S) is preferably 45% by mass or more and 14,400% by mass or less, and more preferably 90% by mass or more and 5,400% by mass or less. The content of flattened inorganic particles (F) relative to magnetic particles (M) is preferably 11% by mass or more and 3600% by mass or less, and more preferably 23% by mass or more and 1350% by mass or less.

[0075] (Method for manufacturing resin compositions) The resin composition according to this embodiment is manufactured by melt-kneading each of the above components. For example, a method for producing the resin composition according to this embodiment is to knead a composition containing polyester resin (P) and wax (W), silica particles (S), and magnetic particles (M) with flat inorganic particles (F), and then knead the resulting mixture with a thermoplastic resin (T) to obtain the resin composition. Here, the above-mentioned compound and the flattened inorganic particles (F) may be mixed together (so-called dry blending) during the molding process when forming the molded body, for example.

[0076] A specific example of the resin composition according to this embodiment is as follows: First, a waste developer is prepared, which is a mixture of waste toner having toner particles containing polyester resin (P) and wax (W), and silica particles (S) externally attached to the toner particles, and a waste carrier consisting of magnetic particles (M). Next, the waste developer and flat inorganic particles (F) are kneaded together to obtain a masterbatch. Alternatively, a recycled resin consisting of a thermoplastic resin (T) may also be kneaded together to obtain the masterbatch. Next, the masterbatch and the recycled resin consisting of thermoplastic resin (T) are kneaded together. The resin composition is obtained through the above operations. The masterbatch may also be the target resin composition.

[0077] Known methods are used for melt mixing. Examples of melt mixing methods include twin-screw extruders, Henschel mixers, Banbury mixers, single-screw extruders, multi-screw extruders, and conical mixers. The temperature during melt mixing (i.e., the cylinder temperature) should be determined according to the melting points of the resin components that make up the resin composition. However, to suppress the decomposition of the wax (W), it is preferable that the temperature during melting and mixing (i.e., the cylinder temperature) be below the decomposition temperature of the wax (W) (for example, 260°C). Furthermore, since the resin composition contains particles containing polyester resin (P) and wax (W), as well as magnetic particles (M), dustproof and explosion-proof measures are necessary for the mixing means. For this reason, it is advisable to use grounding devices for electrostatic countermeasures (such as grounding wires attached to the feeder) and explosion-proof devices (such as Dynisco's "explosion-proof pressure transmitter (SPX2242 series (successor to the old S / E242 series), which conforms to explosion-proof standards such as Japan (TIIS) Ex ia II C T4, Europe ATEX II 2(1)G EEx ia IIC T4 / T6", and America FM Class 1, Div. 1, Groups A, B, C, D)) for melt mixing means such as feeders.

[0078] <Resin molded product> The resin molded article according to this embodiment includes the resin composition according to this embodiment. Specifically, the resin molded article according to this embodiment is, for example, a molded article using the resin composition according to this embodiment.

[0079] In addition, the resin molded article according to this embodiment may be obtained by preparing a resin composition (i.e., pellets) having the same composition as the resin molded article according to this embodiment, and then molding this resin composition. Furthermore, the resin molded article according to this embodiment may be obtained by preparing a resin composition (i.e., a masterbatch) according to this embodiment that contains components other than the thermoplastic resin (T), and then molding a mixture of this composition and the thermoplastic resin (T) during the molding process. However, the masterbatch may contain a small amount of thermoplastic resin (T). The molding method may include, for example, injection molding, extrusion molding, blow molding, hot press molding, calendering, coating molding, casting, dipping, vacuum forming, and transfer molding.

[0080] In this embodiment, injection molding is preferred as a method for molding resin molded articles because it offers a high degree of freedom in shape. Injection molding is performed using commercially available equipment such as the NEX150 and NEX300 manufactured by Nissei Plastic Industrial Co., Ltd., and the SE50D manufactured by Sumitomo Machinery Corporation. The cylinder temperature and mold temperature for injection molding should be determined according to the melting point of the resin components that make up the molded resin product. However, to suppress the decomposition of the wax (W), it is preferable that the cylinder temperature and mold temperature for injection molding be below the decomposition temperature of the wax (W) (for example, 260°C). Furthermore, since the resin composition contains magnetic particles (M), triboelectric charging may occur during injection molding. Therefore, it is advisable to use the aforementioned grounding device and explosion-proof device in the injection molding machine.

[0081] The resin molded body according to this embodiment is suitably used for applications such as electronic and electrical equipment, office equipment, household appliances, automotive interior materials, containers, etc. More specifically, the housings of electronic and electrical equipment, office equipment and household appliances; various parts of electronic and electrical equipment, office equipment and household appliances; interior parts of automobiles; storage cases for CD-ROMs, DVDs, etc.; tableware; beverage bottles; food trays; wrapping materials; films; sheets; and the like.

Example

[0082] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following description, unless otherwise specified, "parts" and "%" are based on mass.

[0083] <PE resin composition> WAX-containing PE resin particles prepared as follows were prepared.

[0084] [Preparation of amorphous polyester resin particle dispersion (A1)] · Ethylene glycol: 37 parts · Neopentyl glycol: 65 parts · 1,9-Nonanediol: 32 parts · Terephthalic acid: 96 parts The above materials were charged into a flask, heated to 200 °C over 1 hour, and after confirming that the reaction system was uniformly stirred, 1.2 parts of dibutyltin oxide was added. The temperature was raised to 240 °C over 6 hours while distilling off the generated water, and stirring was continued at 240 °C for 4 hours to obtain an amorphous polyester resin (acid value 9.4 mgKOH / g, weight average molecular weight 13,000, glass transition temperature 62 °C). The amorphous polyester resin was transferred to an emulsifying disperser (Cavitron CD1010, Eurotech) at a rate of 100 g per minute while in a molten state. Separately, dilute ammonia water with a concentration of 0.37% obtained by diluting reagent ammonia water with ion-exchanged water was placed in a tank, and while heating to 120 °C with a heat exchanger, it was transferred to the emulsifying disperser at a rate of 0.1 liter per minute simultaneously with the amorphous polyester resin. The emulsifying disperser was rotated at a rotor rotation speed of 60 Hz and a pressure of 5 kg / cm 2The system was operated under the specified conditions to obtain an amorphous polyester resin particle dispersion (A1) with a volume-average particle size of 160 nm and a solid content of 20%.

[0085] [Preparation of crystalline polyester resin particle dispersion (C1)] Decandioic acid: 81 parts Hexanediol: 47 parts The above materials were placed in a flask, and the temperature was raised to 160°C over 1 hour. After confirming that the reaction system was uniformly stirred, 0.03 parts of dibutyltin oxide were added. The temperature was raised to 200°C over 6 hours while distilling off the water produced, and stirring was continued at 200°C for 4 hours. Next, the reaction mixture was cooled, solid-liquid separation was performed, and the solid was dried at 40°C under reduced pressure to obtain crystalline polyester resin (C1) (melting point 64°C, weight-average molecular weight 15,000).

[0086] • Crystalline polyester resin (C1): 50 parts • Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 2 parts • Ion-exchanged water: 200 bottles The above materials were heated to 120°C and thoroughly dispersed in a homogenizer (Ultra-Turrax T50, IKA Corporation), followed by dispersion treatment in a pressure-discharge homogenizer. When the volume-average particle size reached 180 nm, the mixture was collected to obtain a dispersion of crystalline polyester resin particles (C1) with a solid content of 20%.

[0087] [Preparation of mold release agent particle dispersion (W1)] • Paraffin wax (HNP-9, manufactured by Nippon Seiro Co., Ltd.): 100 units • Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 1 part • Ion-exchanged water: 350 units The above materials were mixed and heated to 100°C, dispersed using a homogenizer (IKA Ultra-Turrax T50), and then dispersed again using a pressure-discharge type Gorin homogenizer to obtain a release agent particle dispersion containing release agent particles with a volume-average particle size of 200 nm. Deionized water was added to this release agent particle dispersion to adjust the solid content to 20%, resulting in release agent particle dispersion (W1).

[0088] [Preparation of colorant particle dispersion (K1)] • Carbon black (Cabot Regal 330): 50 units • Anionic surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Neogen RK): 5 parts • Ion-exchanged water: 195 units The above materials were mixed and dispersed for 60 minutes using a high-pressure impact disperser (Ultimizer HJP30006, Sugino Machine Co., Ltd.) to obtain a colorant particle dispersion (K1) with a solid content of 20%.

[0089] [Preparation of wax-containing PE resin particles (K1)] • Ion-exchanged water: 200 bottles • Amorphous polyester resin particle dispersion (A1): 180 parts • Crystalline polyester resin particle dispersion (C1): 60 parts • Release agent particle dispersion (W1): 15 parts • Coloring agent particle dispersion (K1): 15 parts • Anionic surfactant (TaycaPower): 2.8 parts The above materials were placed in a round stainless steel flask, and 0.1N nitric acid was added to adjust the pH to 3.5. Then, an aqueous solution of aluminum chloride (Oji Paper Co., Ltd., 30% powder) was added, prepared by dissolving 2 parts of aluminum chloride in 30 parts of deionized water. The mixture was dispersed at 30°C using a homogenizer (IKA Ultra-Turrax T50), and then heated in a heating oil bath to 45°C until the volume-average particle size reached 4.9 μm. Next, 60 parts of amorphous polyester resin particle dispersion (A1) were added and held for 30 minutes. When the volume-average particle size reached 5.2 μm, another 60 parts of amorphous polyester resin particle dispersion (A1) were added and held for another 30 minutes. Subsequently, 20 parts of 10% NTA (nitrilotriacetic acid) metal salt aqueous solution (Kirest 70, Kirest Co., Ltd.) were added, and 1N sodium hydroxide aqueous solution was added to adjust the pH to 9.0. Next, 1 part of anionic surfactant (TaycaPower) was added, and the mixture was heated to 85°C while continuing to stir, and held for 5 hours. Then, it was cooled to 20°C at a rate of 20°C / min. Finally, it was filtered, thoroughly washed with deionized water, and dried to obtain wax-containing PE resin particles (K1) with a volume-average particle size of 5.7 μm and an average circularity of 0.971.

[0090] 100 parts by mass of wax-containing PE resin particles (K1) and 4.5 parts by mass of silica particles (S1) (manufactured by Fujifilm Business Innovation) with an average particle size of 50 nm and an aspect ratio of 1.1 as an external additive were placed in a sample mill and mixed for 30 seconds at a rotation speed of 10,000 rpm. Then, the mixture was sieved using a vibrating sieve with a mesh size of 45 μm to obtain a PE resin composition (K1) with a volume average particle size of 5.7 μm.

[0091] Furthermore, other PE resin compositions were prepared in the same manner as PE resin composition (K1), except that the following items were changed. • Content of amorphous polyester resin and crystalline polyester resin • Type and content of wax • Average particle size and content of silica particles

[0092] <Magnetic particles> Magnetic particles were prepared as follows: [Fabrication of magnetic particles (M1)] 500 parts of spherical magnetite powder particles (volume average particle size: 0.55 μm) were thoroughly mixed in a Henschel mixer, then 5.0 parts of a titanate-based coupling agent were added, and the mixture was heated to 100°C and mixed and stirred for 30 minutes to obtain titanate-based coupling agent-coated spherical magnetite particles. Next, the surface of the titanate-based coupling agent-coated spherical magnetite particles was coated with acrylic resin. This acrylic resin coating allows the particles to withstand shear during mixing and reduces exposure of the magnetite particles. This reduces screw wear and improves recyclability. Next, 6.25 parts of phenol, 9.25 parts of 35% formalin, 500 parts of the magnetite particles, 6.25 parts of 25% aqueous ammonia, and 425 parts of water were added to a four-necked flask and mixed and stirred. Then, the mixture was reacted at 85°C for 120 minutes while stirring, cooled to 25°C, 500 parts of water were added, the supernatant was removed, and the precipitate was washed with water. This was dried under reduced pressure at 150°C to 180°C to obtain magnetic particles (M1) with an average particle size of 50 μm.

[0093] Furthermore, other magnetic particles were prepared in the same manner as magnetic particles (M1), except that the average particle size was changed.

[0094] [Examples 1-30, Comparative Examples 1-11] A mixture of PE resin composition, magnetic particles, flat inorganic particles, other additives, and thermoplastic resin, in the proportions (parts) shown in Tables 1 and 2, was kneaded in a twin-screw kneader (Toshiba Machine, TEM58SS) under the following kneading conditions and at the melt kneading temperature (cylinder temperature) shown in Tables 1 and 2 to obtain resin composition pellets. The proportions of polyester resin (PE resin), wax, silica particles, magnetic particles, flat inorganic particles, and other additives shown in Tables 1 and 2 (indicated as "Total proportions of components excluding thermoplastic resin" in the tables) represent the proportion of solids per 100 parts of thermoplastic resin. -Mixing conditions- • Screw diameter: φ58mm • Rotation speed: 300 rpm • Discharge nozzle diameter: 5mm

[0095] The obtained pellets were used in an injection molding machine (NEX150, manufactured by Nissei Plastic Industrial Co., Ltd.) at the injection molding temperatures (cylinder temperature) and mold temperature of 50°C shown in Tables 1 and 2 to obtain the following test specimens. • ISO multi-purpose dumbbell test specimen (test specimen compliant with ISO 527 tensile test and ISO 178 bending test, test section thickness 4 mm, width 10 mm) • Flat test specimen (length 100mm, width 100mm, thickness 1mm)

[0096] <Examples 31-38> The pellets from Examples 4, 9, 23, and 25 were used as masterbatches (denoted as MB), and the masterbatches and thermoplastic resins were mixed in a twin-screw kneader (Toshiba Machine, TEM58SS) in the composition (parts) shown in Table 3, under the following kneading conditions and at the melt-kneading temperature (cylinder temperature) shown in Table 3, to obtain resin composition pellets. -Mixing conditions- • Screw diameter: φ58mm • Rotation speed: 300 rpm • Discharge nozzle diameter: 5mm

[0097] The obtained pellets were used in an injection molding machine (NEX150, manufactured by Nissei Plastic Industrial Co., Ltd.) at the injection molding temperature (cylinder temperature) and mold temperature of 50°C shown in Table 3 to obtain the following test specimens. • ISO multi-purpose dumbbell test specimen (test specimen compliant with ISO 527 tensile test and ISO 178 bending test, test section thickness 4 mm, width 10 mm) • Flat test specimen (length 100mm, width 100mm, thickness 1mm)

[0098] <Rating> The following evaluations were performed using the obtained pellets or two types of test specimens. The evaluation results are shown in Tables 1 to 3.

[0099] (Moldability) Using pellets, the melt mass flow rate (MFR) was measured according to the method specified in JIS K 7210-1:2014 using a "Melt Indexer G-02 Automatic Load Switching (Multi-Weight) Specification" manufactured by Toyo Seiki Co., Ltd. However, the measurement conditions were set as follows depending on the type of thermoplastic resin. ABS resin: Weight load 9.8kg, temperature 220℃ PP resin: Weight load 2.16kg, temperature 230℃

[0100] (mechanical properties) -Yield stress, tensile fracture strain, and tensile modulus- Using ISO multipurpose dumbbell test specimens, yield stress, tensile fracture strain, and tensile modulus were measured using a universal testing apparatus (Shimadzu Corporation, Autograph AG-Xplus) in accordance with the method specified in ISO 527:2012.

[0101] - Impact strength (impact resistance) - An ISO multipurpose dumbbell test specimen was notched. Then, using the notched test specimen (plate thickness 4 mm), the Charpy impact strength (kJ / m²) was measured using an impact testing apparatus (DG-5, manufactured by Toyo Seiki Seisakusho Co., Ltd.) according to the method specified in ISO 179-1:2010. 2 ) was measured.

[0102] (Stain-resistant) Using flat plate test specimens, the volume resistivity (Ω·m) was measured according to the method specified in JIS C2139-3-1:2018 using an ADC Corporation "Digital Ultra-High Resistivity / Micro-Current Meter 5450". A lower volume resistivity indicates higher antifouling properties. Note that in the table, the notation "(Value 1)E + (Value 2)" means "(Value 1) × 10 +(数値2) This indicates the value of ".

[0103] (Ozone degradation resistance) An ozone degradation test was conducted on an ISO multipurpose dumbbell test specimen using a Suga Test Instruments Co., Ltd. "Ozone Weather Meter OMS-LNZ" in accordance with the method specified in JIS K 6259:2022 (ISO 1431:2022). The conditions for the ozone degradation test were a temperature of 40±2℃, an ozone concentration of 50±5 pphm, and a standing time of 500 hours. Using ISO multipurpose dumbbell test specimens after ozone degradation testing, the yield point stress residual was measured using a universal testing apparatus (Shimadzu Corporation, Autograph AG-Xplus) in accordance with the method specified in ISO 527:2012.

[0104] (Evaluation of processability of strand properties) The properties of the strands in the resin composition pellets extruded from the twin-screw compounding machine were observed and evaluated based on the following two items. -Strand property observation items- • Item DW: Dice swell (Pass if the change from the die diameter is within 5 ± 0.5 mm) • Item DD: Die residue (Pass if there is no extrusion debris) Furthermore, if a candidate passed both of the above two items, they were rated "A"; if they passed only one item, they were rated "B"; and if they failed both items, they were rated "C".

[0105] The details of the materials used are shown below in Tables 1 to 3. (Acrylonitrile butadiene styrene resin (referred to as ABS resin)) • HF380: HF380 (manufactured by LG) • Recycled material: Recycled material (ABS from the tray portion of the Fujifilm Business Innovation collection machine, crushed, washed, dried, and pelletized. Manufactured by Peace Co., Ltd.)

[0106] (Polypropylene resin (referred to as PP resin)) • MA3MA3: MA3MA3 (manufactured by Nippon Polypropylene Co., Ltd.) • Recycled material: Recycled material (manufactured by Peace Co.)

[0107] (Polyester resin (referred to as PE resin)) • (A1): Amorphous polyester resin (acid value 9.4 mg KOH / g, weight-average molecular weight 13,000, glass transition temperature 62°C) • (C1): Crystalline polyester resin (C1) (melting point 64°C, weight-average molecular weight 15,000)

[0108] (Wax (written as WAX)) • (W1): Paraffin wax (HNP-9, manufactured by Nippon Seiro Co., Ltd.)

[0109] (Silica particles) (S1): Silica particles with average particle size Ds=50nm and aspect ratio As=1.1 (S2): Silica particles with average particle size Ds=63nm and aspect ratio As=1.1 (S3): Silica particles with average particle size Ds=71nm and aspect ratio As=1.2 (S4): Silica particles with average particle size Ds=75nm and aspect ratio As=1.1 (S5): Silica particles with average particle size Ds=80nm and aspect ratio As=1.1 The silica particles (S1) to (S5) were prepared in accordance with the method for producing silica particles described in Japanese Patent Application Publication No. 2023-143610.

[0110] (Magnetic particles) (M1): Magnetic particles with an average particle size Dm = 50 μm and an aspect ratio Am = 1.2. (M2): Magnetic particles with an average particle size Dm = 55 μm and an aspect ratio Am = 1.1. (M3): Magnetic particles with an average particle size Dm = 65 μm and an aspect ratio Am = 1.1. (M4): Magnetic particles with an average particle size Dm = 70 μm and an aspect ratio Am = 1.2. (M5): Magnetic particles with an average particle size Dm = 80 μm and an aspect ratio Am = 1.1.

[0111] (Flat inorganic particles (referred to as Flat particles)) • (F1): Talc with average particle size Df=5.5μm and aspect ratio Af=11 (Manufactured by Fujifilm Wako Pure Chemical Industries, Product Code: 202-18251) • (F2): Mica with average particle size Df=8.8μm and aspect ratio Af=88 (Manufactured by Fujifilm Wako Pure Chemical Industries, Product Code: 133-11271) • (F3): Talc with average particle size Df=2.1μm and aspect ratio Af=8 (SG-95 manufactured by Nippon Talc Co., Ltd.) • (F4): Talc with average particle size Df=7.2μm and aspect ratio Af=10 (manufactured by Nippon Talc Co., Ltd.) P-2) • (F5): Talc with average particle size Df=18μm and aspect ratio Af=12 (PA-OG, manufactured by Nippon Talc Co., Ltd., P-2)

[0112] Rubber: SEBS (Hydrogenated Styrene Thermoplastic Elastomer), Asahi Kasei Corporation "ToughTec H1221"

[0113] Note that in Tables 1 to 3, the values ​​indicating composition, except for those in the "mass%" column, represent the number of copies.

[0114] [Table 1]

[0115] [Table 2-1]

[0116] [Table 2-2]

[0117] [Table 2-3]

[0118] [Table 2-4]

[0119] [Table 2-5]

[0120] [Table 3]

[0121] From the above results, it can be seen that the resin composition of this embodiment yields a resin molded article with superior long-term ozone degradation resistance compared to the resin composition of the comparative example. Furthermore, it can be seen that the resin composition of this embodiment yields a resin molded article with excellent elastic modulus, impact resistance, moldability, and stain resistance. Furthermore, it can be seen that the resin composition of this embodiment yields a resin molded article with excellent mechanical properties such as yield stress and fracture strain.

[0122] This embodiment includes the following aspects. (((1))) Polyester resin containing amorphous polyester resin, wax and, Silica particles with an average particle size of 50 nm to 80 nm, A core material containing magnetic powder, and a coating resin layer covering the core material, comprising magnetic particles with an average particle size of 30 μm or more and 80 μm or less, Flattened inorganic particles with an average major diameter of 5 μm or more and 10 μm or less, Thermoplastic resins other than the aforementioned polyester resin, A resin composition containing the following: (((2))) A resin composition (((1))) wherein the average aspect ratio of the flattened inorganic particles is 5 or more and 100 or less. (((3))) (((2))) a resin composition wherein the average aspect ratio of the flattened inorganic particles is 5 or more and 50 or less. (((4))) A resin composition according to any one of (((1))) to (((3))), wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 69 or more and 176 or less. (((5))) A resin composition (((4))) wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 73 or more and 110 or less. (((6))) A resin composition according to any one of (((1))) to (((5))), wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the magnetic particles is 0.069 or more and 0.176 or less. (((7))) The polyester resin content is 1.5 parts by mass or more and 52 parts by mass or less per 100 parts by mass of the thermoplastic resin. The wax content is 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The silica particle content is 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The content of the magnetic particles is 0.3 parts by mass or more and 10.3 parts by mass or less per 100 parts by mass of the thermoplastic resin. A resin composition according to any one of (((1))) to (((6))), wherein the content of the flattened inorganic particles is 0.3 parts by mass or more and 160 parts by mass or less per 100 parts by mass of the thermoplastic resin. (((8))) The content of the flattened inorganic particles relative to the silica particles is 90% by mass or more and 5400% by mass or less. A resin composition according to any one of (((1))) to (((7))), wherein the content of the flat inorganic particles relative to the magnetic particles is 23% by mass or more and 1350% by mass or less. (((9))) A resin molded article comprising the resin composition described in any one of items (((1))) to (((8))). (((10))) A method for producing a resin composition according to any one of (((1))) to (((8))), comprising kneading a composition containing the polyester resin and the wax, the silica particles and the magnetic particles with the flat inorganic particles, and then kneading the resulting mixture with the thermoplastic resin to obtain a resin composition.

[0123] The effects of the above embodiment are as follows: According to the invention of (((1))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to a resin composition comprising a polyester resin, wax, silica particles with an average particle size of 50 nm to 80 nm, a core material containing magnetic powder, and a coating resin layer covering the core material, and comprising magnetic particles with an average particle size of 30 μm to 80 μm, flat inorganic particles with an average major diameter of less than 5 μm, and a thermoplastic resin other than polyester resin. According to the invention of (((2))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to cases where the average aspect ratio of flattened inorganic particles is less than 5 or greater than 100. According to the invention of (((3))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to cases where the average aspect ratio of flattened inorganic particles is less than 5 or greater than 50. According to the invention of (((4))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to cases where the ratio of the average major axis of flattened inorganic particles to the average particle size of silica particles is less than 69 or greater than 176. According to the invention of (((5))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to cases where the ratio of the average major axis of flattened inorganic particles to the average particle size of silica particles is less than 73 or greater than 110. According to the invention of (((6))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to cases where the ratio of the average major axis of flattened inorganic particles to the average particle size of magnetic particles is less than 0.069 or greater than 0.176. According to the invention of (((7))), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to the case where the content of any of the components in the thermoplastic resin does not meet the above range. According to the invention of ((8)), a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to the case where the content of flattened inorganic particles relative to silica particles or magnetic particles does not meet the above range.

[0124] According to the invention of (((9))), a resin molded article is provided that has superior long-term ozone degradation resistance compared to a resin molded article to which a resin composition is applied, which includes a polyester resin, wax, silica particles with an average particle size of 50 nm to 80 nm, a core material containing magnetic powder, and a coating resin layer covering the core material, and which includes magnetic particles with an average particle size of 30 μm to 80 μm, flat inorganic particles with an average major diameter of less than 5 μm, and a thermoplastic resin other than polyester resin.

[0125] According to the invention of (((10))), a method for producing a resin composition is provided that yields a resin molded article with superior long-term ozone degradation resistance compared to a method for producing a resin composition by kneading a composition containing polyester resin and wax particles, silica particles with an average particle size of 50 nm to 80 nm, and magnetic particles, with flat inorganic particles with an average major diameter of less than 5 μm, and then kneading the resulting kneaded product with a thermoplastic resin.

Claims

1. Polyester resin containing amorphous polyester resin, wax and, Silica particles with an average particle size of 50 nm to 80 nm, A core material containing magnetic powder, and a coating resin layer covering the core material, comprising magnetic particles with an average particle size of 30 μm or more and 80 μm or less, Flattened inorganic particles with an average major diameter of 5 μm or more and 10 μm or less, Thermoplastic resins other than the aforementioned polyester resin, A resin composition containing the following:

2. The resin composition according to claim 1, wherein the average aspect ratio of the flattened inorganic particles is 5 or more and 100 or less.

3. The resin composition according to claim 2, wherein the average aspect ratio of the flattened inorganic particles is 5 or more and 50 or less.

4. The resin composition according to claim 1, wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 69 or more and 176 or less.

5. The resin composition according to claim 4, wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the silica particles is 73 or more and 110 or less.

6. The resin composition according to claim 1, wherein the ratio of the average major axis of the flattened inorganic particles to the average particle size of the magnetic particles is 0.069 or more and 0.176 or less.

7. The polyester resin content is 1.5 parts by mass or more and 52 parts by mass or less per 100 parts by mass of the thermoplastic resin. The wax content is 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The silica particles are contained in an amount of 0.1 parts by mass or more and 2.6 parts by mass or less per 100 parts by mass of the thermoplastic resin. The content of the magnetic particles is 0.3 parts by mass or more and 10.3 parts by mass or less per 100 parts by mass of the thermoplastic resin. The resin composition according to claim 1, wherein the content of the flattened inorganic particles is 0.3 parts by mass or more and 160 parts by mass or less per 100 parts by mass of the thermoplastic resin.

8. The content of the flattened inorganic particles relative to the silica particles is 90% by mass or more and 5400% by mass or less. The resin composition according to claim 1, wherein the content of the flattened inorganic particles relative to the magnetic particles is 23% by mass or more and 1350% by mass or less.

9. A resin molded article comprising the resin composition according to any one of claims 1 to 8.

10. A method for producing a resin composition according to any one of claims 1 to 8, comprising kneading a composition containing the polyester resin and the wax, the silica particles and the magnetic particles with the flat inorganic particles, and then kneading the resulting mixture with the thermoplastic resin to obtain a resin composition.

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