Resin composition, molded article and electrical device

Abstract

To provide a resin composition that has good fire retardancy and is capable of inhibiting occurrence of fogging.SOLUTION: A resin composition of the invention includes polyolefin, phosphinic acid metal salt, an NOR type hindered amine compound, and metalhydroxide. A ratio of the phosphinic acid metal salt to the resin composition is 1-6 mass%. A ratio of the NOR type hindered amine compound to the resin composition is 0.05-5 mass%. A ratio of the metalhydroxide to the resin composition is 5-60 mass%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a molded article using the resin composition, and an electrical device having the molded article. [Background technology]

[0002] Polyolefins such as polypropylene are used in a variety of applications due to their low carbon dioxide emissions during production, light weight, excellent chemical resistance, and low cost. However, because polyolefins are highly flammable, molded articles made from polyolefins often require flame retardancy. To impart flame retardancy to molded articles containing polyolefins, a large amount of flame retardant must be added, which can easily impair the properties of polyolefins.

[0003] Known flame retardants include halogen-based and non-halogen-based flame retardants. Halogen-based flame retardants can impart flame retardancy in small amounts, thereby suppressing the deterioration of the mechanical properties of resins to some extent. However, halogen-based flame retardants can generate large amounts of dioxin-based compounds when burned and decomposed, making them undesirable from an environmental perspective. On the other hand, phosphorus-containing compounds are known as non-halogen flame retardants that can impart flame retardancy to molded articles (see, for example, Patent Documents 1 and 2).

[0004] Patent Document 1 discloses a resin composition containing polypropylene, silicone oil, a silicone resin, and a phosphorus-containing compound that is a non-halogen flame retardant.

[0005] Patent Document 2 discloses a resin composition containing polyolefin, a phenolic resin, a phosphorus-containing compound that is a non-halogen flame retardant, and expandable graphite. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 14277 / 1983 [Patent Document 2] Japanese Patent Application Publication No. 9-111059 Summary of the Invention [Problem to be solved by the invention]

[0007] However, although non-halogen flame retardants such as those described in Patent Documents 1 and 2 do not contain harmful halogens, they have inferior flame retardancy compared to halogen flame retardants and therefore need to be blended in large amounts into resin compositions. Resin compositions containing large amounts of non-halogen flame retardants cause bleed-out and a decrease in the mechanical properties of the resin, making it difficult to achieve both improved flame retardancy and improved mechanical properties.

[0008] When expandable graphite is used in combination with the resin composition described in Patent Document 2, the appearance of the molded product is significantly deteriorated. In particular, when a phosphate ester is used as the phosphorus-containing compound in Patent Document 2, it is thought that this may cause bleed-out or a decrease in heat resistance.

[0009] Examples of products that incorporate flame-retardant molded parts include electrical equipment such as office machines. In electrical equipment, molded parts that require flame retardancy are often located near power sources or in or near electrically conductive parts, making them susceptible to high temperatures. Furthermore, molded parts are sometimes exposed to high temperatures not only during use of the electrical equipment, but also in the cargo compartments of ships during shipping and transportation. When molded parts are exposed to high temperatures, they can develop fogging (a phenomenon in which volatile components from the molded part adhere to the surfaces of other parts, causing them to cloud over). Fogging not only impairs the appearance of electrical equipment, but can also impair the functionality that the molded part is intended to perform.

[0010] Furthermore, due to the recent COVID-19 pandemic, logistics have been halted, and these electrical devices have been stored for longer periods of time in warehouses and on ships. This has resulted in increased temperatures and longer storage periods, which has made fogging more apparent, and conventional technologies have not been able to sufficiently suppress it.

[0011] An object of the present invention is to provide a resin composition that has good flame retardancy and can suppress the occurrence of fogging. Another object of the present invention is to provide a molded article including the resin composition and an electrical device including the molded article. [Means for solving the problem]

[0012] A resin composition according to one embodiment of the present invention includes a polyolefin, a metal phosphinate, a NOR hindered amine compound, and a metal hydroxide, wherein the ratio of the metal phosphinate to the resin composition is within a range of 1 to 6 mass%, the ratio of the NOR hindered amine compound to the resin composition is within a range of 0.05 to 5 mass%, and the ratio of the metal hydroxide to the resin composition is within a range of 5 to 60 mass%.

[0013] A molded article according to one embodiment of the present invention is molded using the resin composition of the present invention.

[0014] An electrical device according to an embodiment of the present invention includes the molded article of the present invention. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide a resin composition that has good flame retardancy and can suppress the occurrence of fogging. Furthermore, according to the present invention, it is possible to provide a molded article including the resin composition and an electrical device including the molded article. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, a resin composition, a molded article, and an electrical device according to embodiments of the present invention will be described in detail.

[0017] (Configuration of Resin Composition) The resin composition contains a polyolefin, a metal phosphinate, a NOR-type hindered amine compound, and a metal hydroxide.

[0018] Polyolefins are the base material for resin compositions. Polyolefins are homopolymers or copolymers polymerized with olefins as the main monomer component. Here, "olefin" refers to an aliphatic chain unsaturated hydrocarbon having one double bond.

[0019] Polyolefins include copolymers of olefins with other olefins, or copolymers of olefins with other monomers copolymerizable with olefins.

[0020] The olefin is preferably an α-olefin having 2 to 12 carbon atoms. Examples of the α-olefin include ethylene, propylene, 1-butene, isobutene, 1-pentene, 3-methyl-1-butene, 1-hexene, 1-octene, 1-decene, and 1-dodecene. One type of olefin may be used alone, or two or more types may be used in combination.

[0021] Examples of other monomers copolymerizable with α-olefins include cyclic olefins such as cyclopentene and norbornene, and dienes such as 1,4-hexadiene and 5-ethylidene-2-norbornene. Examples of other monomers include vinyl acetate, styrene, (meth)acrylic acid and its derivatives, vinyl ether, maleic anhydride, carbon monoxide, and N-vinylcarbazole. When polymerizing polyolefins, one type of other monomer may be used alone, or two or more types may be used in combination. Note that "(meth)acrylic acid" refers to at least one of acrylic acid and methacrylic acid.

[0022] Examples of polyolefins include polyethylenes whose main component is ethylene, such as high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE); polypropylene-based resins whose main component is propylene, such as polypropylene (propylene homopolymer), ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-butene copolymer, and ethylene-propylene-diene copolymer; polybutene; and polypentene.

[0023] Further examples of polyolefin resins include ethylene-vinyl acetate copolymer (EVA), ethylene-ethyl acrylate copolymer, polyketone, copolymers produced with metallocene catalysts, and chemically modified versions of these polymers, such as ionomer resins, saponified EVA, and olefin elastomers produced by dynamic vulcanization in an extruder.

[0024] The polyolefin resin is preferably a polyethylene resin or a polypropylene resin, more preferably a polypropylene resin. The stereoregularity of the propylene-derived structure in the polypropylene resin may be any of isotactic, syndiotactic, and atactic.

[0025] Examples of commercially available polyolefins include the polypropylene resin series "Prime Polypro," "Polyfine," and "Prime TPO" (e.g., Prime Polypro J715M) manufactured by Prime Polymer Co., Ltd., and the polyethylene resin series "Hi-Zex," "Neo-Zex," "Ult-Zex," "Moatec," and "Evolue" (e.g., Hi-Zex 1300J) manufactured by Prime Polymer Co., Ltd.

[0026] The polyolefin is preferably polypropylene, more preferably propylene homopolymer, from the viewpoint of easily increasing the strength and heat resistance of the molded article.

[0027] The proportion of polyolefin in the resin composition is in the range of 29.0 to 93.95% by mass, preferably in the range of 50 to 75% by mass. When the proportion of polyolefin in the resin composition is 29.0% by mass or more, the properties of the polyolefin are more easily obtained, and when it is 93.95% by mass or less, the strength of the molded article is more easily increased.

[0028] The method for detecting polyolefins is not particularly limited. Polyolefins can be detected by known methods. For example, polyolefins can be detected by combining IR (infrared spectroscopy), DSC (differential scanning calorimetry), NMR (nuclear magnetic resonance spectroscopy), etc.

[0029] The metal phosphinate functions as a flame retardant and can be represented by the following formula:

[0030] [ka]

[0031] R 1 and R 2 is hydrogen or alkyl having 1 to 8 carbon atoms, or R 1 and R 2 Each of the symbols represents an alkyl group having 1 to 8 carbon atoms. Each of n and m represents an alkyl group having 1 to 3. M represents an alkali metal, an alkaline metal, or aluminum.

[0032] The metal phosphinate is R 1 and R 2 is an ethyl group and M is aluminum diethylphosphinate, or R 1 and R 2 Calcium phosphinates where is hydrogen and M is calcium are preferred.

[0033] The ratio of the metal phosphinate to the resin composition is in the range of 1 to 6% by mass, preferably in the range of 2 to 5% by mass. If the ratio of the metal phosphinate to the resin composition is less than 1% by mass, the combustion rank and combustion time described below will be poor. If the ratio of the metal phosphinate to the resin composition is more than 6% by mass, fogging will occur.

[0034] The method for detecting metal phosphinate is not particularly limited. Metal phosphinate can be detected by a known method. For example, metal phosphinate can be detected by a combination of ion chromatography, capillary electrophoresis, ICP-AES (inductively coupled plasma atomic emission spectroscopy), ICP-MS (inductively coupled plasma mass spectroscopy), atomic absorption spectroscopy, X-ray fluorescence spectroscopy, etc.

[0035] The NOR type hindered amine compound functions as a light stabilizer. The NOR type hindered amine compound has an alkoxyimino group. The side chain of the alkoxyimino group represents a substituted or unsubstituted, saturated or unsaturated hydrocarbon group. Examples of the side chain include an alkyl group, an aralkyl group, and an aryl group. The alkyl group may be linear, branched, or cyclic, or may be a combination of these.

[0036] The NOR hindered amine compound is not particularly limited as long as it has an alkoxyimino group structure. Examples of the NOR hindered amine compound include the NOR hindered amine compounds described in JP-A-2002-507238, WO-A-2005 / 082852, WO-A-2008 / 003605, etc.

[0037] NOR type hindered amine compounds include compounds represented by the following formula:

[0038] [ka]

[0039] In the formula, G 1 and G 2 Z independently represents an alkyl group having 1 to 4 carbon atoms or a pentamethylene group. 1 and Z 2 represents a methyl group, or Z 1 and Z 2forms a bridging moiety. The bridging moiety can be further bonded to the organic group via an ester group, an ether group, an amide group, an amino group, a carbonyl group, or a urethane group. E represents an alkoxy group having 1 to 18 carbon atoms, a cycloalkoxy group having 5 to 12 carbon atoms, an aralkoxy group having 7 to 25 carbon atoms, or an aryloxy group having 6 to 12 carbon atoms.

[0040] The NOR type hindered amine compound represented by the above formula is preferably a high molecular weight compound from the viewpoint of flame retardancy and heat resistance. The high molecular weight compound is generally an oligomeric or polymeric compound. The number of repeating units of the high molecular weight oligomeric or polymeric compound is preferably in the range of 2 to 100, more preferably in the range of 5 to 80.

[0041] The NOR type hindered amine compounds also include compounds represented by the following formula:

[0042] [ka]

[0043] In the formula, R 1 ~R 4 R represents a hydrogen atom or an organic group of the following formula: 1 ~R 4 At least one of the groups is an organic group shown below.

[0044] [ka]

[0045] In the formula, R 5 represents an alkyl group having 1 to 17 carbon atoms, a cycloalkyl group having 5 to 10 carbon atoms, a phenyl group, or a phenylalkyl group having 7 to 15 carbon atoms. 6 ~R 9 R represents an alkyl group having 1 to 4 carbon atoms. 10 represents a hydrogen atom or a linear or branched alkyl group having 1 to 12 carbon atoms.

[0046] R 5 Among alkyl groups having 1 to 17 carbon atoms, R is preferably a methyl group, a propyl group, or an octyl group. 5 Among cycloalkyl groups having 5 to 10 carbon atoms, a cyclohexyl group is preferred. 5 Of the phenyl group and phenylalkyl groups having 7 to 15 carbon atoms, R is preferably a phenyl group. 6 ~R 9 Among alkyl groups having 1 to 4 carbon atoms, R is preferably a methyl group. 10 Among the linear or branched alkyl groups having 1 to 12 carbon atoms, an n-butyl group is preferred.

[0047] Specific examples of NOR-type hindered amine compounds include 1-cyclohexyloxy-2,2,6,6-tetramethyl-4-octadecylaminopiperidine; bis(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)sebacate; 2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-6-(2-hydroxyethylamino)-s-triazine; bis(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)adipate; 4, Oligomeric compounds which are condensation products of 4'-hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2,4-dichloro-6-[(1-octyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine end-capped with 2-chloro-4,6-bis(dibutylamino)-s-triazine; 4,4'-hexamethylenebis(amino-2,2,6,6-tetramethylpiperidine) and 2, Oligomeric compounds that are condensation products with 4-dichloro-6-[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)butylamino]-s-triazine; 2,4-bis[(1-cyclohexyloxy-2,2,6,6-piperidin-4-yl)-6-chloro-s-triazine; and the reaction of peroxidized 4-butylamino-2,2,6,6-tetramethylpiperidine with 2,4,6-trichloro-s-triazine, cyclohexane, and N,N'-ethane-1,2-diylbis(1,3-propanediamine). The products include (N,N',N'''-tris{2,4-bis[(1-cyclohexyloxy-2,2,6,6-tetramethylpiperidin-4-yl)n-butylamino]-s-triazin-6-yl}-3,3'-ethylenediiminodipropylamine); bis(1-undecanoxy-2,2,6,6-tetramethylpiperidin-4-yl)carbonate; 1-undecyloxy-2,2,6,6-tetramethylpiperidin-4-one; and bis(1-stearyloxy-2,2,6,6-tetramethylpiperidin-4-yl)carbonate.

[0048] Examples of commercially available NOR-type hindered amine compounds include the "Flamestab" series (eg, NOR116FF) and the "TINUVIN" series (eg, NOR371FF) manufactured by BASF.

[0049] The proportion of the NOR hindered amine compound in the resin composition is in the range of 0.05 to 5% by mass, preferably 0.2 to 2.0% by mass. If the proportion of the NOR hindered amine compound in the resin composition is less than 0.05% by mass, the flame retardancy will be insufficient, and if it exceeds 5% by mass, the impact strength will be insufficient.

[0050] The method for detecting NOR hindered amine compounds is not particularly limited. NOR hindered amine compounds can be detected by known methods. For example, NOR hindered amine compounds can be detected by combining pyrolysis GC / MS (pyrolysis gas chromatography / mass spectrometry) and IR (infrared spectroscopy).

[0051] The metal hydroxide functions as a flame retardant and a neutralizing agent. The type of metal hydroxide is not particularly limited as long as it can exhibit the above-mentioned functions. The metal hydroxide may be a simple metal hydroxide or a composite metal hydroxide. Examples of simple metal hydroxides include aluminum hydroxide and magnesium hydroxide. The composite metal hydroxide may be a hydrotalcite compound containing two or more metal elements, at least one of which is magnesium and the other metal elements are selected from calcium, aluminum, tin, titanium, iron, cobalt, nickel, copper, and zinc. From the viewpoint of suppressing the occurrence of fogging, aluminum hydroxide is preferred as the metal hydroxide. Furthermore, the metal hydroxide may be surface-treated with a coupling agent such as a silane, epoxy, or titanate-based agent to improve dispersibility in the resin composition and the strength of the molded product.

[0052] The ratio of the metal hydroxide to the resin composition is in the range of 5 to 60% by mass, preferably in the range of 10 to 30% by mass. If the ratio of the metal hydroxide to the resin composition is less than 5% by mass, the flammability rating, burning time, fogging, impact strength, and flexural modulus will decrease. On the other hand, if the ratio of the metal hydroxide to the resin composition is more than 60% by mass, the impact strength will decrease.

[0053] The average particle size (median size) of the metal hydroxide is not particularly limited. The average particle size of the metal hydroxide is preferably in the range of 0.1 to 5.5 μm, more preferably in the range of 0.5 to 2.0 μm. The method for measuring the average particle size of the metal hydroxide is not particularly limited. The average particle size of the metal hydroxide is the so-called median size, and can be measured using a UPA-150 (Microtrac Bell Co., Ltd.).

[0054] The method for detecting metal hydroxides is not particularly limited. Metal hydroxides can be detected by known methods. For example, metal hydroxides can be detected by combining XPS (X-ray photoelectron spectroscopy), SEM-EDS (scanning electron microscopy-energy dispersive X-ray spectroscopy), TG-DTA (thermogravimetric differential thermal analysis), Raman spectroscopy, etc.

[0055] The resin composition of the present invention may contain other components, such as flame retardants, inorganic fillers, impact modifiers, crystal nucleating agents, antioxidants, light stabilizers, antistatic agents, lubricants, plasticizers, pigments, dyes, etc., in addition to the above-mentioned components, as long as the effects of the present invention are not impaired. Known components may also be contained as additives.

[0056] <Other flame retardants> Examples of other flame retardants other than the above-mentioned flame retardants include phosphorus-based flame retardants such as phosphate esters, ammonium polyphosphate, and guanidine phosphate, nitrogen-based flame retardants such as melamine cyanurate and guanidine compounds, and silicone-based flame retardants. One type of other flame retardant may be used alone, or two or more types may be used in combination.

[0057] <Filler> Fillers are broadly classified into organic and inorganic fillers. Examples of organic fillers include starch, cellulose particles, cellulose fibers, wood flour, soybean pulp, rice husks, bran, and other naturally occurring polymers, as well as modified versions of these. High-melting organic fibrous materials such as polyamides, fluororesins, and acrylic resins can also be used.

[0058] The inorganic filler may be fibrous, granular, or plate-like. Examples of fibrous fillers include glass fiber, carbon fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, wollastonite, barium sulfate fiber, and metal fibers such as stainless steel, aluminum, titanium, copper, and brass.

[0059] Examples of powdery and granular fillers include carbon black, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, metal oxides such as iron oxide, titanium oxide, and alumina, metal carbonates such as calcium carbonate and magnesium carbonate, metal sulfates such as calcium sulfate and barium sulfate, as well as silicon carbide, silicon nitride, boron nitride, and various metal powders. Examples of plate-like inorganic fillers include mica, glass flakes, layered silicates, and various metal foils. One type of filler may be used alone, or two or more types may be used in combination.

[0060] <Impact modifier> The impact modifier is preferably a thermoplastic elastomer primarily composed of olefin-derived structural units, such as ethylene propylene diene rubber (EPDM). Thermoplastic elastomers can also be used, particularly those containing olefin-derived structural units. Examples of thermoplastic elastomers include methyl methacrylate-butadiene-styrene copolymer (MBS), acrylonitrile-butadiene-styrene copolymer (ABS), styrene-butadiene-styrene copolymer (SBS), styrene-ethylene-butylene-styrene block copolymer (SEBS), ethylene-octene copolymer (EOR), and butyl acrylate-methyl methacrylate copolymer. SEBS and EOR are preferred impact modifiers from the viewpoints of compatibility and flame retardancy of the resin composition, as well as dispersibility of the thermoplastic elastomer in the resin composition. One type of impact modifier may be used alone, or two or more types may be used in combination.

[0061] <Nucleating agent> Known crystal nucleating agents can be used, and examples of the crystal nucleating agent include metal salts of carboxylic acids, dibenzyl sorbitol derivatives, and alkali metal salts of phosphoric acid. Specific examples of the crystal nucleating agent include sodium benzoate, aluminum adipate, pt-butylaluminum benzoate, 1,3,2,4-dibenzylidenesorbitol, 1,3,2,4-bis(p-methyl-benzylidene)sorbitol, 1,3,2,4-bis(p-ethylbenzylidene)sorbitol, 1,3-p-chlorobenzylidene-2,4-p-methylbenzylidene)sorbitol, sodium bis(4-t-butylphenyl)phosphate, sodium bis(4-t-methylphenyl)phosphate, potassium bis(4,6-di-t-butylphenyl)phosphate, sodium 2,2′-methylene-bis(4,6-di-t-butylphenyl)phosphate, and sodium 2,2′-ethylidene-bis(4,6-di-t-butylphenyl)phosphate.

[0062] <Antioxidants> Examples of antioxidants include phenol-based antioxidants, phosphorus-based antioxidants, and sulfur-based antioxidants. The antioxidant is preferably a phenol-based antioxidant, and more preferably an alkyl-substituted phenol-based antioxidant. One type of antioxidant may be used alone, or two or more types may be used in combination.

[0063] <Light resistance stabilizer> Examples of the light resistance stabilizer include benzophenone-based light resistance stabilizers, benzotriazole-based light resistance stabilizers, and NH-type and N-methyl-type hindered amine-based light resistance stabilizers. One type of light resistance stabilizer may be used alone, or two or more types may be used in combination.

[0064] <Antistatic agent> Examples of antistatic agents include cationic antistatic agents such as fatty acid quaternary ammonium ion salts and polyamine quaternary salts; anionic antistatic agents such as higher alcohol phosphate ester salts, higher alcohol EO adducts, polyethylene glycol fatty acid esters, anionic alkyl sulfonates, higher alcohol sulfate ester salts, higher alcohol ethylene oxide adduct sulfate ester salts, and higher alcohol ethylene oxide adduct phosphate ester salts; nonionic antistatic agents such as polyhydric alcohol fatty acid esters, polyglycol phosphate esters, and polyoxyethylene alkyl allyl ethers; and amphoteric antistatic agents such as amphoteric alkyl betaines such as alkyl dimethylaminoacetic acid betaine and imidazoline-type amphoteric surfactants. One type of antistatic agent may be used alone, or two or more types may be used in combination.

[0065] <Lubricant> Examples of lubricants include fatty acid salts, fatty acid amides, silane polymers, solid paraffin, liquid paraffin, magnesium stearate, calcium stearate, zinc stearate, stearic acid amide, silicone powder, methylene bisstearic acid amide, and N,N'-ethylene bisstearic acid amide. One type of lubricant may be used alone, or two or more types may be used in combination.

[0066] <Plasticizer> Examples of plasticizers include polyethylene glycol, polyamide oligomer, ethylene bisstearamide, phthalate ester, adipate ester, polystyrene oligomer, polyethylene wax, silicone oil, and mineral oil. One type of plasticizer may be used alone, or two or more types may be used in combination.

[0067] The content of other additives in the resin composition of the present invention is within a range that does not impair the effects of the present invention, for example, within a range of approximately 0.1 to 30 mass % relative to the total amount of the resin composition, and preferably within a range of 0.1 to 20 mass %.

[0068] The method for producing the resin composition is not particularly limited. The resin composition can be produced, for example, by mixing the components and melt-kneading them.

[0069] The melt-kneading in this embodiment is carried out using a kneading device such as a Banbury mixer, a roll, a plastograph, an extruder (such as a single-screw extruder or a multi-screw extruder (e.g., a twin-screw extruder)), or a kneader. From the viewpoint of production efficiency, it is preferable to use an extruder for the melt-kneading. Furthermore, from the viewpoint of imparting high shearing properties, it is more preferable to use a multi-screw extruder, and particularly preferably a twin-screw extruder, for the melt-kneading. Here, the term extruder is used in a category that includes an extrusion kneader.

[0070] The temperature during melt-kneading (melt-kneading temperature) is equal to or higher than the melting temperature of the polyolefin-based resin. The melt-kneading temperature is preferably 150 to 250°C and is appropriately selected depending on the polyolefin-based resin used. When a polypropylene-based resin is used as the polyolefin-based resin, the melt-kneading temperature is preferably 160 to 220°C. When an extruder is used for melt-kneading, the kneading melt temperature corresponds to the cylinder temperature.

[0071] Before melt-kneading, the components may be mixed (dry blended) in advance using various mixers such as a tumbler or a high-speed mixer known as a Henschel mixer.

[0072] In the manufacturing method of this embodiment, the molten kneaded material is extruded into a strand shape, and then the extruded strand shape kneaded material can be processed into a pellet shape, a flake shape, or the like.

[0073] The resin composition of the present invention can be in various forms such as powder, granules, tablets, pellets, and flakes.

[0074] The resin composition in the embodiment can be molded into any shape to form a molded article. Examples of molding methods for the molded article include injection molding, extrusion molding, blow molding, vacuum molding, profile extrusion molding, compression molding, and gas-assisted molding.

[0075] When an injection-molded article is produced using the resin composition of this embodiment, a conventionally known injection molding machine can be used. The injection-molded article can be produced by melting the resin composition in a cylinder, injecting the molten resin composition into a mold, and cooling and solidifying it. The injection speed and pressure are adjusted appropriately. The injection molding conditions are preferably, for example, a cylinder temperature (melt temperature) of 170 to 230°C and a mold temperature of 40 to 80°C.

[0076] The shape and dimensions of the molded article are not particularly limited and can be set arbitrarily depending on the application of the molded article.

[0077] Molded articles can be used for interior or exterior parts of electrical equipment such as home appliances, office automation and media-related equipment, optical equipment, and communication equipment, as well as automobile and machine parts, and housing and building materials. Because the molded articles have excellent strength, good flame retardancy, and a low environmental impact, they are ideal for use as exterior parts (especially housings) for electrical equipment such as copiers, printers, personal computers, and televisions.

[0078] The mechanism by which the resin composition can exhibit its effects is presumed to be as follows. It has been known that resin compositions containing a polyolefin, a metal phosphinate, and a NOR-type hindered amine compound exhibit flame retardancy. Although it has been known that conventional resin compositions exhibit flame retardancy, it has not been known what other effects they have. The present inventors have found that molded articles produced using conventional flame-retardant resin compositions suffer from fogging in high-temperature environments during storage, transportation, use, etc. of the molded article alone or an assembly using the molded article. In this embodiment, by adding a metal hydroxide to the polyolefin, metal phosphinate, and NOR-type hindered amine compound, it is possible to maintain flame retardancy and suppress the occurrence of fogging even when the content of the metal phosphinate is reduced.The cause of fogging is thought to be that the acid components generated from the metal phosphinate during melt-kneading decompose the polyolefin, resulting in low-molecular-weight compounds that remain in the molded product, which volatilize in a high-temperature environment and adhere to other parts. Metal hydroxides exhibit combustibility through an endothermic reaction during combustion, so flame retardancy can be maintained even when the amount of metal phosphinate added is reduced. Furthermore, metal hydroxides can neutralize acid components generated during melt-kneading, which is thought to significantly reduce fogging by suppressing the generation of low-molecular-weight compounds. [Example]

[0079] Example 1 73.5% by mass of polypropylene (a polyolefin), 1.0% by mass of aluminum diethylphosphinate (a metal phosphinate), 25% by mass of aluminum hydroxide (average particle size 0.7 μm) (a metal hydroxide), and 0.5% by mass of NOR-1 (a NOR-type hindered amine compound) were melt-kneaded. Melt-kneading was performed using a twin-screw extruder ("TEX30α" manufactured by The Japan Steel Works, Ltd.) at a cylinder temperature of 180°C and a screw rotation speed of 150 rpm. The strands extruded from the extruder were cut using a pelletizer and processed into pellets measuring 2 mm in diameter and 3 mm in length to produce a resin composition.

[0080] <Example 2> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 72.5% by mass and the aluminum diethylphosphinate content was 2.0% by mass.

[0081] Example 3 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 71.95% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the NOR-1 content was 0.05% by mass.

[0082] Example 4 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 71.5% by mass and the aluminum diethylphosphinate content was 3.0% by mass.

[0083] <Example 5> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 67.0% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the NOR-1 content was 5.0% by mass.

[0084] Example 6 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 91.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the aluminum hydroxide content was 5% by mass.

[0085] Example 7 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 86.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the aluminum hydroxide content was 10% by mass.

[0086] Example 8 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 71.5% by mass and the aluminum diethylphosphinate content was 3.0% by mass.

[0087] Example 9 A resin composition was prepared in the same manner as in Example 1, except that polypropylene was used at 71.5 mass %, aluminum diethylphosphinate was used at 3.0 mass %, and aluminum hydroxide (average particle size 0.1 μm), which is a metal hydroxide, was used at 25 mass %.

[0088] Example 10 A resin composition was prepared in the same manner as in Example 1, except that polypropylene was used at 71.5 mass %, aluminum diethylphosphinate was used at 3.0 mass %, and aluminum hydroxide (average particle size 5.5 μm), which is a metal hydroxide, was used at 25 mass %.

[0089] Example 11 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 66.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the aluminum hydroxide content was 30% by mass.

[0090] Example 12 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 36.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the metal hydroxide, aluminum hydroxide, was 60% by mass.

[0091] Example 13 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 69.5% by mass and the aluminum diethylphosphinate content was 5.0% by mass.

[0092] Example 14 A resin composition was prepared in the same manner as in Example 1, except that the amount of polyethylene, which is a polyolefin, was 69.5% by mass and the amount of aluminum diethylphosphinate was 5.0% by mass.

[0093] Example 15 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 69.5% by mass and calcium phosphinate as the metal phosphinate was 5.0% by mass.

[0094] Example 16 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 69.5% by mass, the aluminum diethylphosphinate content was 5.0% by mass, and magnesium hydroxide as the metal hydroxide was 25% by mass.

[0095] Example 17 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 69.5% by mass, the aluminum diethylphosphinate content was 5.0% by mass, and the NOR-2, a NOR-type hindered amine compound, was 0.5% by mass.

[0096] Example 18 A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 68.5% by mass and the aluminum diethylphosphinate content was 6.0% by mass.

[0097] Example 19 A resin composition was prepared in the same manner as in Example 1, except that polypropylene was used at 71.5 mass %, aluminum diethylphosphinate was used at 3.0 mass %, and aluminum hydroxide (average particle diameter 0.05 μm), which is a metal hydroxide, was used at 25 mass %.

[0098] Example 20 A resin composition was prepared in the same manner as in Example 1, except that polypropylene was used at 71.5 mass %, aluminum diethylphosphinate was used at 3.0 mass %, and aluminum hydroxide (average particle size 10.5 μm), which is a metal hydroxide, was used at 25 mass %.

[0099] <Comparative Example 1> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 74.0% by mass and the aluminum diethylphosphinate content was 0.5% by mass.

[0100] <Comparative Example 2> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 31.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the aluminum hydroxide content was 65% by mass.

[0101] <Comparative Example 3> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 67.5% by mass and the aluminum diethylphosphinate content was 7.0% by mass.

[0102] <Comparative Example 4> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 93.5% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the aluminum hydroxide content was 3% by mass.

[0103] <Comparative Example 5> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 71.97% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the NOR-1 content was 0.03% by mass.

[0104] <Comparative Example 6> A resin composition was prepared in the same manner as in Example 1, except that the polypropylene content was 66.0% by mass, the aluminum diethylphosphinate content was 3.0% by mass, and the NOR-1 content was 6.0% by mass.

[0105] The polyolefins used were Prime Polypro J715M (Prime Polymer Co., Ltd.) for polypropylene and HJ560 (Japan Polyethylene Co., Ltd.). The metal phosphinates used were OP930 (Clariant) for aluminum diethylphosphinate and 98% pure calcium phosphinate (Fujifilm Wako Pure Chemical Industries). The metal hydroxides used were KH-108 (KC Corporation) for aluminum hydroxide with an average particle size of 0.7 μm, NP-ALO-15 (EM Japan Co., Ltd.) for aluminum hydroxide with an average particle size of 0.1 μm, NP-ALO-14 (EM Japan Co., Ltd.) for aluminum hydroxide with an average particle size of 0.05 μm, B-308 (Armorix Co., Ltd.) for aluminum hydroxide with an average particle size of 10.5 μm, and Magseeds X (Konoshima Chemical Co., Ltd.). As the NOR-type hindered amine compounds, Flamestab NOR116FF (BASF) was used for NOR-1, and TINUVIN NOR371FF (BASF) was used for NOR-2.

[0106] The components contained in Examples 1 to 20 and Comparative Examples 1 to 6 are shown in Table 1.

[0107] [Table 1]

[0108] [Evaluation method] (Evaluation of flammability) Pellets of the resin composition of each example and comparative example were dried at 80°C for 4 hours, and then molded into test pieces for evaluating flammability (total length 125 mm, thickness 1.6 mm, width 13 mm) using an injection molding machine (J140AD-110H, manufactured by The Japan Steel Works, Ltd.) under conditions of a cylinder temperature of 185 to 200°C and a mold temperature of 80°C. Using the obtained test pieces, flammability was evaluated in accordance with the UL94V standard (20 mm vertical flame test). A "good" on the following evaluation criteria was considered to be a pass, and a "bad" was considered to be a fail. Evaluation criteria ○: V-2 ×: Non-conformance

[0109] (Burning time evaluation) In the above-mentioned evaluation of flammability, the burning time of each test piece was compared with n=5. If the following evaluation criteria were met, a "Good" or "Good" was considered to be a pass, and if it was met, a "Poor" was considered to be a fail. Evaluation criteria ○: The burning time of each test piece (n=5) was 20 seconds or less. △: The burning time of each test piece (n=5) exceeded 20 seconds, but all were 30 seconds or less. ×: The burning time of each test piece (n=5) exceeded 30 seconds.

[0110] (Fogging evaluation) Test pieces measuring 13 mm x 13 mm x 1.6 mm were cut from the above-described flammability evaluation test pieces to prepare test pieces for fogging evaluation. The test pieces for fogging evaluation obtained from the resin compositions of the Examples and Comparative Examples were placed in glass sample bottles with a volume of 50 ml, a diameter of 34 mm, a height of 80 mm, and an opening diameter of 20 mm. The top opening of each sample bottle was covered with a glass plate. The sample bottles containing the test pieces were heated on a hot plate from the bottom at 80°C for 14 days. The degree of fogging (light transmittance at a wavelength of 589 nm) of the glass plate with the top opening of the sample bottle covered was measured using a V-670 spectrophotometer (JASCO Corporation), and the difference from the light transmittance of the glass plate before and after the test was calculated. A high degree of fogging, i.e., a large decrease in transmittance, was evaluated as having fogging. A rating of "Good" or "Good" according to the following evaluation criteria was considered a pass, and a rating of "Poor" was considered a fail. Evaluation criteria ○: The decrease in transmittance was less than 0.5% △: The decrease in transmittance was 0.5% or more and less than 2% ×: The transmittance decreased by 2% or more

[0111] (Impact strength evaluation) Pellets of the resin composition of each example and comparative example were dried at 80°C for 4 hours, and then molded into test pieces for evaluating Charpy impact strength (total length 80 mm, thickness 4 mm, width 10 mm, notch width 8 mm) using an injection molding machine (J140AD-110H, manufactured by The Japan Steel Works, Ltd.) under conditions of a cylinder temperature of 185 to 200°C and a mold temperature of 80°C. The Charpy impact strength of the obtained test pieces was measured in accordance with ISO 179. The Charpy impact strength of 10 test pieces was measured, and the number average value was calculated. A score of "Good" or "Good" according to the following evaluation criteria was considered to be acceptable, and a score of "Poor" was considered to be unacceptable. Evaluation criteria ○: 10kJ / m 2 End △: 6kJ / m 2 More than 10kJ / m 2 less than × : 6kJ / m 2 less than

[0112] (Evaluation of flexural modulus) Pellets of the resin composition of each example and comparative example were dried at 80°C for 4 hours, and then molded into bending evaluation test pieces (total length 80 mm, thickness 4 mm, width 10 mm) using an injection molding machine (J140AD-110H, manufactured by The Japan Steel Works, Ltd.) under conditions of a cylinder temperature of 185 to 200°C and a mold temperature of 80°C. The bending modulus of the obtained test pieces was measured in accordance with ISO 178. The bending modulus of five test pieces was measured, and the number average value was calculated. A rating of "Good" or "Good" according to the following evaluation criteria was considered to be acceptable, and a rating of "Poor" was considered to be unacceptable. Evaluation criteria ○: 1500MPa or more △: 1200MPa or more and less than 1500MPa ×: Less than 1200 MPa

[0113] The evaluation results for Examples 1 to 20 and Comparative Examples 1 to 6 are shown in Table 2.

[0114] [Table 2]

[0115] As shown in Tables 1 and 2, a comparison between Example 1 and Comparative Example 1 shows that when the aluminum dialkylphosphinate was less than 1% by mass, the combustion rank and combustion time were not good. A comparison between Example 18 and Comparative Example 3 shows that when the aluminum dialkylphosphinate was more than 6% by mass, the fogging was not good. A comparison between Example 12 and Comparative Example 2 shows that when the metal hydroxide was more than 60% by mass, the impact strength was not good. A comparison between Example 4 and Comparative Example 4 shows that when the metal hydroxide was more than 60% by mass, the impact strength was not good.

[0116] As shown in Tables 1 and 2, a comparison between Example 13 and Example 14 showed that the use of polypropylene as the polyolefin rather than polyethylene resulted in a better burn time. A comparison between Example 1 and Example 2 and Examples 13 and 18 showed that the burn time, fogging, and impact strength were better when the metal phosphinate content was within the range of 2 to 5 mass%. A comparison between Example 5 and Example 6 and Examples 11 and 12 showed that the burn time, flexural modulus, and impact strength were better when the metal hydroxide content was within the range of 10 to 30 mass%. A comparison between Example 13 and Example 15 showed that the burn time was better when aluminum dialkylphosphinate was used rather than calcium phosphinate. A comparison between Examples 8 and 10 showed that the fogging and flexural modulus were better when the average particle size of the metal hydroxide was within the range of 0.1 to 5.5 μm. A comparison between Examples 16 and 17 showed that aluminum hydroxide had better fogging properties than magnesium hydroxide.

[0117] According to this embodiment, the resin composition (molded article) contains polyolefin, metal phosphinate, NOR-type hindered amine compound, and metal hydroxide in predetermined proportions, and therefore has good flammability, burning time, fogging, impact strength, and flexural modulus. [Industrial Applicability]

[0118] According to the present invention, it is possible to provide a resin composition, a molded article, and an electrical device that have good flame retardancy even when the content of a flame retardant is small and that can suppress fogging.

Claims

1. A resin composition comprising a polyolefin, a metal phosphinate, a NOR-type hindered amine compound, and a metal hydroxide, the ratio of the metal phosphinate to the resin composition is within a range of 1 to 6 mass %, the ratio of the NOR hindered amine compound to the resin composition is within a range of 0.05 to 5% by mass, The ratio of the metal hydroxide to the resin composition is within the range of 5 to 60 mass%. Resin composition.

2. The resin composition according to claim 1 , wherein the polyolefin is polypropylene.

3. The resin composition according to claim 1, wherein the ratio of the metal phosphinate to the resin composition is within a range of 2 to 5 mass%.

4. The resin composition according to claim 1, wherein the ratio of the metal hydroxide to the resin composition is within a range of 10 to 30 mass %.

5. The resin composition according to claim 1 , wherein the metal phosphinate is an aluminum dialkylphosphinate.

6. 2. The resin composition according to claim 1, wherein the average particle size of the metal hydroxide is in the range of 0.1 to 5.5 μm.

7. The resin composition according to claim 1 , wherein the metal hydroxide is aluminum hydroxide.

8. A molded article molded using the resin composition according to any one of claims 1 to 7.

9. An electrical device comprising the molded article according to claim 8.

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