Resin composition and molded article using same

Abstract

The purpose of the present invention is to provide: a resin composition which produces little fisheye when formed into a film; and a film which uses the resin composition. The resin composition comprises 70-98.99 parts by weight (inclusive) of thermoplastic resin (A) containing at least two components of polyolefin and derived from recycled products of used plastic products, 1-29.99 parts by weight (inclusive) of compatibilizer (B), and fatty acid metal salt (C) or ethylene-vinyl acetate copolymer saponified product (D) 0.01-5 parts by weight (inclusive) of at least one of the components (A), (B), (C) and / or (D)) (the total of (A), (B), (C) and / or (D) is 100 parts by weight).

Description

Technical Field

[0001] The present invention relates to a resin composition comprising a thermoplastic resin derived from recycled material of post-use plastic articles. Background Art

[0002] In recent years, concerns about environmental pollution caused by plastics have been increasing, and material recycling of plastic products is being promoted.

[0003] When recycling plastics, mixing different types of plastics in recycled plastic waste typically leads to poor compatibility, which can degrade the physical properties of the recycled plastics. Therefore, currently, recycled plastic waste is sorted into its raw materials before being recycled into products.

[0004] However, multilayer films and multilayer containers obtained by laminating different types of plastics (hereinafter referred to as composite plastics) cannot be reused because it is difficult to distinguish the raw materials. Currently, they are disposed of by landfill or incineration.

[0005] Against this backdrop, the addition of compatibilizers is being studied as a means of recycling composite plastics.

[0006] For example, it has been reported that adding a compatibilizer to composite plastics such as polyethylene (PE) and polyethylene terephthalate (PET), or polypropylene (PP) and acrylonitrile-butadiene-styrene copolymer (ABS) can improve the physical properties of the composite plastics (see Patent Document 1).

[0007] However, while researching the recycling of composite plastics, the present inventors discovered that when recycled resins containing PET and polyamide in polyolefins are formed into films, a visual defect known as fisheyes frequently occurs. Furthermore, this visual defect is not limited to recycled resins containing polyolefins and resins other than polyolefins; it can also occur in recycled resins containing two or more polyolefin resins, depending on the combination of these two types of polyolefins.

[0008] Prior art literature

[0009] Patent Literature

[0010] Patent Document 1: Japanese Patent Application Laid-Open No. 2001-220473 Summary of the Invention

[0011] Problems to be solved by the invention

[0012] An object of the present invention is to provide a resin composition that generates few fish eyes during film formation, and a film using the resin composition.

[0013] Solutions to the Problem

[0014] To solve the above-mentioned problems, the present inventors conducted intensive research and found that a resin composition containing a compatibilizer and a lubricating component in predetermined amounts added to recycled used plastic products containing two or more thermoplastic resins, including at least a polyolefin, exhibits minimal fisheye formation during film formation, leading to the completion of the present invention.

[0015] That is, the various aspects of the present invention are as follows [1] to

[15] .

[0016] [1] A resin composition comprising:

[0017] 70 parts by weight or more and 98.99 parts by weight or less of two or more thermoplastic resins (A) derived from recycled materials of used plastic products and containing at least polyolefin;

[0018] 1 part by weight or more and 29.99 parts by weight or less of a compatibilizer (B); and

[0019] 0.01 parts by weight or more and 5 parts by weight or less of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D) (the total of (A), (B), and (C) and / or (D) is 100 parts by weight).

[0020] [2] The resin composition according to [1] above, wherein

[0021] The thermoplastic resin (A) contains at least one resin selected from polyester, polyamide, and ethylene-vinyl alcohol copolymer as a component other than polyolefin.

[0022] [3] The resin composition according to [2] above, wherein

[0023] The polyester is polyethylene terephthalate, and the polyamide is nylon 6 or nylon 66.

[0024] [4] The resin composition according to any one of [1] to [3] above, wherein

[0025] The compatibilizer (B) is ethylene-vinyl acetate copolymer and / or maleic anhydride-modified polyolefin.

[0026] [5] The resin composition according to any one of [1] to [4] above, wherein

[0027] The fatty acid metal salt (C) is at least one selected from stearates of magnesium, calcium or zinc, and hydroxystearates.

[0028] [6] The resin composition according to any one of [1] to [5] above, wherein

[0029] The ethylene-vinyl acetate copolymer saponified product (D) is a saponified product of an ethylene-vinyl acetate copolymer having an ethylene content of 75 mol% to 95 mol% and a vinyl acetate content of 5 mol% to 25 mol%.

[0030] The degree of saponification of the vinyl acetate component is 20% by weight or more.

[0031] [7] The resin composition according to any one of [1] to [6] above, wherein

[0032] The melt flow rate of the saponified ethylene-vinyl acetate copolymer (D) measured at 190° C. and a load of 2160 g in accordance with JIS K6924-1 is 40 g / 10 minutes or more.

[0033] [8] The resin composition according to any one of [1] to [7] above, wherein

[0034] The used plastic product is at least one selected from the group consisting of food packaging containers, sanitary product packaging containers, cosmetic packaging containers, and daily necessities packaging containers.

[0035] [9] A film comprising the resin composition according to any one of [1] to [8] above.

[0036]

[10] A multilayer film comprising at least one layer formed from the resin composition according to any one of [1] to [8] above.

[0037]

[11] A packaging container comprising the film described in [9] above.

[0038]

[12] A packaging container comprising the film described in

[10] above.

[0039]

[13] A method for manufacturing a film, which is a method for manufacturing the film described in [9] above, comprising:

[0040] The resin composition described in any one of [1] to [8] is molded at 190° C. or higher and 250° C. or lower.

[0041]

[14] A method for manufacturing a multilayer film, which is a method for manufacturing the multilayer film described in

[10] above, comprising:

[0042] The resin composition described in any one of [1] to [8] is molded at 190° C. or higher and 250° C. or lower.

[0043]

[15] A method for producing a resin composition, comprising the step of obtaining a molten mixture, wherein:

[0044] The molten mixture comprises:

[0045] 70 parts by weight or more and 98.99 parts by weight or less of two or more thermoplastic resins (A) derived from recycled materials of used plastic products and containing at least polyolefin;

[0046] 1 part by weight or more and 29.99 parts by weight or less of a compatibilizer (B); and

[0047] 0.01 parts by weight or more and 5 parts by weight or less of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D).

[0048] Effects of the Invention

[0049] The resin composition of one embodiment of the present invention has few fish eyes when formed into a film and is therefore useful as a raw material for recycled products having excellent appearance. DETAILED DESCRIPTION

[0050] Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

[0051] A resin composition according to one embodiment of the present invention comprises: 70 parts by weight or more and 98.99 parts by weight or less of a thermoplastic resin (A) derived from recycled materials of used plastic products and containing at least two components of polyolefins; 1 part by weight or more and 29.99 parts by weight or less of a compatibilizer (B); and 0.01 part by weight or more and 5 parts by weight or less of at least one selected from a fatty acid metal salt (C) or a saponified ethylene-vinyl acetate copolymer (D).

[0052] The thermoplastic resin (A) containing at least two or more components of polyolefins is composed of two or more thermoplastic resins, and it is sufficient as long as it contains polyolefin as at least one of the thermoplastic resins. That is, the thermoplastic resin (A) may contain polyolefins and thermoplastic resins other than polyolefins, or may contain two or more components (two or more) of polyolefins. From the viewpoint of further suppressing the formation of fisheyes, the thermoplastic resin (A) containing at least two or more components of polyolefins preferably contains polyolefins and resins other than polyolefins. As components of the resin other than polyolefins, polyamides, ethylene-vinyl alcohol copolymers, polyesters, polystyrene, etc. can be mentioned.

[0053] Examples of polyolefins include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-acrylate copolymer, and ethylene-methacrylate copolymer. One or more of these can be used. It should be noted that, in this specification, low-density polyethylene refers to a polyethylene having a density of 910 kg / m 3 Above and below 930kg / m 3High-density polyethylene refers to polyethylene with a density of 930kg / m 3 The density of polyethylene can be measured in accordance with JIS K6922-1 (2011).

[0054] Examples of the polyamide include nylon 6, nylon 6,6, nylon 11, and nylon 12, and these may be used alone or in combination.

[0055] Examples of the polyester include polyethylene terephthalate, glycol-modified polyethylene terephthalate (PETG resin), polybutylene terephthalate, and polylactic acid. These may be used alone or in combination of two or more.

[0056] Among these, the resin contained in the thermoplastic resin (A) comprising at least two components of a polyolefin is preferably at least one selected from high-density polyethylene, low-density polyethylene, linear low-density polyethylene, and polypropylene, and more preferably at least one selected from low-density polyethylene and linear low-density polyethylene, from the viewpoint of excellent film formability. As a resin other than a polyolefin, it is preferably at least one selected from polyester, polyamide, and ethylene-vinyl alcohol copolymer. As a polyester, polyethylene terephthalate is more preferably used, and as a polyamide, at least one selected from nylon 6 and nylon 6,6 is more preferably used.

[0057] The thermoplastic resin (A) comprising at least two or more components of polyolefins is derived from recycled materials of used plastic products. Here, recycled materials derived from used plastic products refer to materials using recycled materials of used plastic products as a raw material. For example, thermoplastic resin (A) includes thermoplastic resins contained in recycled materials of used plastic products. It should be noted that the thermoplastic resin (A) comprising at least two or more components of polyolefins may be derived not only from recycled materials of a single used plastic product but also from recycled materials of two or more used plastic products.

[0058] Recyclables from used plastic products may contain thermoplastic resins and may also contain other components besides thermoplastic resins. For example, recyclables from used plastic products may contain thermoplastic resins such as resin film layers, and may also contain printed layers (layers formed by offset printing, screen printing, gravure printing, flexographic printing, etc.), protective layers (coated with dielectric printed layers, varnishes, cellulose nanofibers (CNF), etc., UV absorbing layers, etc.), and inorganic layers (metal layers such as aluminum foil, etc.) on the surface or between layers. Furthermore, recyclables from used plastic products may include a vapor-deposited resin film layer in which an inorganic oxide (such as silicon dioxide or aluminum oxide) or a metal (such as aluminum) is vapor-deposited on the surface of the resin film layer.

[0059] As for the ratio of the thermoplastic resin contained in the thermoplastic resin (A) of two or more components containing at least polyolefin, from the viewpoint of excellent film strength, the polyolefin is preferably 70 parts by weight or more and 99 parts by weight or less per 100 parts by weight of the thermoplastic resin (A), and the thermoplastic resin other than the polyolefin is preferably 1 part by weight or more and 30 parts by weight or less.

[0060] The recyclables of used plastic products are the recyclables of items that have been temporarily used as products in the market. As a specific example, the recyclables of packaging containers can be exemplified. The packaging container is not particularly limited. Based on the safety of the contents and the safety of the materials used for the plastic packaging container, preferably, a plastic packaging container discarded by consumers and formed of a multilayer structure such as a food packaging container, a sanitary product packaging container, a cosmetic packaging container, and a daily necessities packaging container. The recyclables of plastic products can be reusable plastic products. Based on the viewpoint of reducing plastic waste, it is preferred to use these wastes, or they can be mixed. In addition, the shape is not particularly limited, and examples include: film-shaped, bottle-shaped, pouch-shaped, cup-shaped, disc-shaped, tubular, etc.

[0061] Alternatively, scraps generated during the manufacturing process of plastic products, which themselves have no value as finished products, may be used as recycled materials from used plastic products. However, in order to reduce marine plastics, recycled materials from used plastic products preferably include recycled materials from plastic products discarded by consumers, and preferably, 100% by weight of the thermoplastic resin (A) containing at least two components of polyolefins should be derived from such recycled materials (waste).

[0062] The compatibilizer (B) is not particularly limited as long as it can compatibilize the thermoplastic resin (A) containing at least two components of polyolefin, and examples thereof include ethylene-vinyl acetate copolymers, acid-modified polyolefins, ethylene-glycidyl methacrylate copolymers, ionomer resins, Oxazoline-based resins and the like can be used alone or in combination.

[0063] Specific examples of the acid-modified polyolefin include maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride-modified ethylene-propylene (block or random) copolymers, maleic anhydride-modified ethylene-ethyl acrylate copolymers, and maleic anhydride-modified ethylene-vinyl acetate copolymers. One or more of these can be used.

[0064] Examples of the ionomer resin include ethylene-methacrylic acid copolymer ionomers, propylene-methacrylic acid copolymer ionomers, butylene-methacrylic acid copolymer ionomers, and ethylene-vinyl sulfonic acid copolymer ionomers. One or more of these may be used. Examples of the counter ions of the ionomer resin include lithium ions, sodium ions, potassium ions, magnesium ions, calcium ions, and zinc ions.

[0065] As containing Oxazoline-based resins include Oxazoline-based polystyrene, etc.

[0066] Among these, when the compatibilizer (B) is at least one of ethylene-vinyl acetate copolymer and maleic anhydride-modified polyethylene, it is preferred because of its excellent film formability and film strength. When it is ethylene-vinyl acetate copolymer, it is more preferred because of its excellent film appearance.

[0067] The ethylene-vinyl acetate copolymer may be an ethylene-vinyl acetate copolymer composition comprising a plurality of ethylene-vinyl acetate copolymers having different vinyl acetate contents. In this case, from the perspective of compatibility, the number of types of ethylene-vinyl acetate copolymers is preferably three or more. Furthermore, from the perspective of compatibility, when the ethylene-vinyl acetate copolymer composition comprising the plurality of ethylene-vinyl acetate copolymers is taken as 100% by mass, the difference in vinyl acetate content between the individual ethylene-vinyl acetate copolymers is preferably 40% by weight or less, and the difference in vinyl acetate content between at least one group of ethylene-vinyl acetate copolymers is preferably 5% by weight or more.

[0068] The compatibilizer (B) preferably has a melt flow rate of 1 g / 10 min or higher, more preferably 5 g / 10 min or higher, as measured in accordance with JIS K6924-1 (under conditions of 190°C and a load of 2160 g). The upper limit of the melt flow rate is not particularly limited, but is, for example, 1000 g / 10 min or lower. This facilitates compatibilization of the various thermoplastic resins contained in the thermoplastic resin (A).

[0069] The fatty acid metal salt (C) is not particularly limited, but is preferably at least one selected from stearates and hydroxystearates of magnesium, calcium, or zinc because of its excellent fish-eye suppressing effect.

[0070] Examples of these fatty acid metal salts include magnesium stearate, calcium stearate, zinc stearate, magnesium hydroxystearate, calcium hydroxystearate, and zinc hydroxystearate.

[0071] The ethylene-vinyl acetate copolymer saponified product (D) is a saponified product obtained by partially or completely converting the vinyl acetate moieties of the ethylene-vinyl acetate copolymer into vinyl alcohol by a hydrolysis method. Specifically, the ethylene-vinyl acetate copolymer saponified product (D) may be a saponified product in which only a portion of the vinyl acetate moieties of the ethylene-vinyl acetate copolymer are modified into vinyl alcohol, or may be a saponified product in which all of the vinyl acetate moieties of the ethylene-vinyl acetate copolymer are modified into vinyl alcohol.

[0072] The ethylene-vinyl acetate copolymer saponified product (D) is not particularly limited. However, when the total of the ethylene content and the vinyl acetate content is 100 mol%, preferably, a saponified product obtained by saponifying a copolymer of ethylene and vinyl acetate having an ethylene content of 75 mol% to 95 mol% and a vinyl acetate content of 5 mol% to 25 mol%, and more preferably, a saponified product obtained by saponifying a copolymer of ethylene and vinyl acetate having an ethylene content of 85 mol% to 95 mol% and a vinyl acetate content of 5 mol% to 15 mol%.

[0073] The saponification degree of the vinyl acetate component calculated in accordance with JIS K7192 (1999) is preferably 20% by weight or more, more preferably 30% by weight or more and 100% by weight or less, further preferably 61% by weight or more and 100% by weight or less, and particularly preferably 70% by weight or more and 100% by weight or less.

[0074] The melt flow rate of the saponified ethylene-vinyl acetate copolymer (D), as measured in accordance with JIS K6924-1 (under conditions of 190°C and a load of 2160 g), is preferably 40 g / 10 min or higher, more preferably 100 g / 10 min or higher, and particularly preferably 200 g / 10 min or higher. The upper limit of the melt flow rate is not particularly limited, but is, for example, 1000 g / 10 min or lower. This can further suppress the accumulation of resin in the molding machine.

[0075] Such a saponified ethylene-vinyl acetate copolymer can be appropriately selected from commercially available products, and is currently commercially available from Tosoh Corporation under the trade name of Melthene H.

[0076] The content ratio of the thermoplastic resin (A) containing at least two components of polyolefins, the compatibilizer (B), the fatty acid metal salt (C), and / or the ethylene-vinyl acetate copolymer saponified product (D) is 70 parts by weight to 98.99 parts by weight of the thermoplastic resin (A), 1 part by weight to 29.99 parts by weight of the compatibilizer (B), and 0.01 part by weight to 5 parts by weight of the fatty acid metal salt (C) and / or the ethylene-vinyl acetate copolymer saponified product (D). Here, the total of (A), (B), (C), and / or (D) is 100 parts by weight.

[0077] It should be noted that, when the resin composition of the present invention contains only one of the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D), the content ratio of the fatty acid metal salt (C) and / or the ethylene-vinyl acetate copolymer saponified product (D) (0.01 parts by weight or more and 5 parts by weight or less) refers to the content ratio of only one of them. When the resin composition of the present invention contains both the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D), it refers to the total content ratio of the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D). When the resin composition of the present invention contains only one of the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D), 100 parts by weight of the total of (A), (B), (C) and / or (D) means the total content of the thermoplastic resin (A), the compatibilizer (B) and the one (the fatty acid metal salt (C) or the ethylene-vinyl acetate copolymer saponified product (D)) is 100 parts by weight. When the resin composition of the present invention contains both the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D), the total content of the thermoplastic resin (A), the compatibilizer (B), the fatty acid metal salt (C) and the ethylene-vinyl acetate copolymer saponified product (D) is 100 parts by weight.

[0078] The content ratio of each component in the resin composition of this embodiment is more preferably 80 parts by weight or more and 98.9 parts by weight or less of the thermoplastic resin (A) containing at least two components of polyolefins, 1 part by weight or more and 19.9 parts by weight or less of the compatibilizer (B), and 0.1 part by weight or more and 3 parts by weight or less of the fatty acid metal salt (C) and / or ethylene-vinyl acetate copolymer saponification product (D). It is most preferably 90 parts by weight or more and 98.8 parts by weight or less of the thermoplastic resin (A) containing at least two components of polyolefins, 1 part by weight or more and 9.8 parts by weight or less of the compatibilizer (B), and 0.2 part by weight or more and 2 parts by weight or less of the fatty acid metal salt (C) and / or ethylene-vinyl acetate copolymer saponification product (D). It should be noted that the total of (A), (B), (C), and (D) is 100 parts by weight.

[0079] A compatibilizer (B) content of 1 part by weight or greater is preferred, as it provides excellent heat seal strength and film appearance. A content of 29.99 parts by weight or less is preferred, as it provides excellent film formability. Furthermore, a fatty acid metal salt (C) and / or ethylene-vinyl acetate copolymer saponified product (D) content of 0.01 parts by weight or greater is preferred, as it provides excellent fisheye suppression effects. A content of 5 parts by weight or less is preferred, as it does not deteriorate film formability.

[0080] In addition to the above components ((A), (B), (C), and / or (D)), the resin composition may also contain a virgin resin as needed. The virgin resin that can be contained is not particularly limited, but linear low-density polyethylene and low-density polyethylene are preferred from the perspective of excellent film formability.

[0081] The melt flow rate (MFR) of the resin composition measured at 190°C and a load of 2160 g is not particularly limited, but from the viewpoint of excellent film formability, it is preferably 0.5 g / 10 min or more and 30 g / 10 min or less, more preferably 0.8 g / 10 min or more and 20 g / 10 min or less, and most preferably 1 g / 10 min or more and 10 g / 10 min or less.

[0082] The method for producing the resin composition includes the step of obtaining a molten mixture (hereinafter also referred to as the "molten mixture") comprising 70 parts by weight to 98.99 parts by weight of a thermoplastic resin (A) derived from recycled materials of used plastic products and containing at least two components of polyolefins, 1 part by weight to 29.99 parts by weight of a compatibilizer (B), and 0.01 part by weight to 5 parts by weight of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D). The molten mixture is a solid mixture obtained by cooling a mixed melt, and can be obtained by mixing and cooling a melt (hereinafter also referred to as the "melt") containing 70 parts by weight to 98.99 parts by weight of the thermoplastic resin (A), 1 part by weight to 29.99 parts by weight of the compatibilizer (B), and 0.01 part by weight to 5 parts by weight of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D).

[0083] The mixing of the melt is not particularly limited as long as it can disperse the components, and can be produced by a commonly used resin mixing device. For example, mixing devices such as single-screw extruders, twin-screw extruders, multi-screw extruders, Banbury mixers, pressure kneaders, rotating rollers, and internal mixers can be mentioned. Among them, twin-screw extruders are preferred from the viewpoint of excellent dispersibility and continuous production.

[0084] The screw speed during kneading in a twin-screw extruder is not particularly limited, but kneading is preferably performed at a speed of 50 rpm to 3000 rpm, more preferably 150 rpm to 1000 rpm. A screw speed of 50 rpm or higher is preferred because it improves the dispersibility of the mixed components and improves the physical properties of the resulting resin. A screw speed of 3000 rpm or lower is also preferred because it prevents resin degradation due to excessive shear heat generation and improves the physical properties of the resulting resin.

[0085] The melt is a melt in which at least one of the following components, thermoplastic resin (A), compatibilizer (B), fatty acid metal salt (C), and / or ethylene-vinyl acetate copolymer saponified product (D), is melted. Preferably, the melt is a melt in which all of the following components, thermoplastic resin (A), compatibilizer (B), fatty acid metal salt (C), and / or ethylene-vinyl acetate copolymer saponified product (D), are melted. The melt can be obtained by heating a raw material containing thermoplastic resin (A), compatibilizer (B), fatty acid metal salt (C), and / or ethylene-vinyl acetate copolymer saponified product (D) at a predetermined ratio to a temperature above the melting point of the component with the lowest melting point among these components (or above the glass transition temperature if the component with the lowest melting point is an amorphous resin). The upper limit of the heating temperature is not particularly limited, but is preferably 300°C or lower.

[0086] It should be noted that when the resin composition of the present embodiment contains other components in addition to the thermoplastic resin (A), the compatibilizer (B), the fatty acid metal salt (C) and / or the ethylene-vinyl acetate copolymer saponified product (D), the other components may be contained in the melt in addition to the thermoplastic resin (A), the compatibilizer (B), the fatty acid metal salt (C) and / or the ethylene-vinyl acetate copolymer saponified product (D).

[0087] The cooling temperature of the mixed melt may be any temperature at which the obtained molten mixture becomes solid. For example, it may be a temperature lower than the melting point of the component with the lowest melting point among the thermoplastic resin (A), the compatibilizer (B), the fatty acid metal salt (C) and / or the saponified ethylene-vinyl acetate copolymer (D) (lower than the glass transition temperature if the component with the lowest melting point is an amorphous resin).

[0088] The resin composition may contain other components in addition to the thermoplastic resin (A), the compatibilizer (B), the fatty acid metal salt (C), and / or the ethylene-vinyl acetate copolymer saponified product (D) within the scope of not impairing the effects of the present invention. Such other components may include one or more of an antistatic agent, a light stabilizer, an ultraviolet absorber, a nucleating agent, an antioxidant, an anti-blocking agent, a flow improver, a mold release agent, a flame retardant, a colorant, an inorganic neutralizer, a hydrochloric acid absorber, a conductive filler, a chain extender, an anti-hydrolysis agent, and the like.

[0089] Furthermore, the resin composition can be used in any form such as pellets or powder.

[0090] There are no particular restrictions on the molding method of the resin composition, and examples thereof include profile extrusion, film molding, sheet molding, blow molding, injection molding, foam molding, extrusion coating, rotational molding, etc. Among them, film molding is preferred from the viewpoint of excellent moldability of the resin composition of the present invention.

[0091] About the forming method of film, there is no particular restriction, can exemplify: blow molding method, coextrusion blow molding method, T-die forming method, coextrusion T-die forming method, calendering method, compression molding method etc.Among these, consider from the viewpoint of productivity excellence, preferred blow molding method, coextrusion blow molding method, T-die forming method, coextrusion T-die forming method.In addition, film of the present invention can be stacked with other films, about stacking method, there is no particular restriction equally, can exemplify dry lamination method, extrusion lamination method, sandwich lamination method etc.

[0092] The resin composition of the present embodiment described above can suppress the generation of fish eyes during film formation. Note that fish eyes are particle-like masses resembling fish eyes that are generated by foreign matter (unmelted matter, etc.) generated in the film.

[0093] The film of one embodiment of the present invention can be obtained by filmizing the above-mentioned resin composition (molding into a film shape). The film formed by the above-mentioned resin composition can be used in the state of one layer or a multilayer film. The laminated structure of the multilayer film is not particularly limited. For example, it can include not only the resin composition (I) layer of the present invention, but also a layer formed by other components, such as a native resin layer (II), an adhesive layer (III), and a barrier layer (IV). Specifically, it can include: (I) / (II), (II) / (I) / (II), (I) / (III) / (IV) / (III) / (I), (I) / (III) / (IV) / (III) / (II), etc. The thickness of the film formed by the above-mentioned resin composition is not particularly limited. From the viewpoint of further suppressing the generation of fish eyes, it is preferably 10μm~300μm.

[0094] The film forming temperature is preferably in the range of 190°C to 250°C, more preferably in the range of 200°C to 250°C, and even more preferably in the range of 220°C to 250°C. A forming temperature of 190°C or higher reduces the formation of fisheyes, while a forming temperature of 250°C or lower is preferred because film formability is excellent.

[0095] The films are useful as packaging containers for foods, daily necessities, industrial parts, pharmaceuticals, office supplies, chemicals, etc., surface protection films, agricultural films such as silage films, heat shrink films, transport bags, and the like.

[0096] Example

[0097] Hereinafter, the present invention will be described based on Examples and Comparative Examples, but the present invention is not limited thereto.

[0098] (1) Melt flow rate (MFR)

[0099] The MFR of the resin used in the examples was measured using a Melt Indexer (manufactured by Takara Industries) at 190° C. and a load of 2160 g in accordance with JIS K6924-1.

[0100] (2) Vinyl acetate content and saponification degree

[0101] Using ethylene-vinyl acetate copolymer or saponified ethylene-vinyl acetate copolymer, the vinyl acetate content was measured in accordance with JIS K7192 (1999), and the saponification degree (weight %) was calculated using the following calculation formula.

[0102] Saponification degree (weight %) = 100 × {(vinyl acetate content (weight %) of ethylene-vinyl acetate copolymer before hydrolysis) - (vinyl acetate content (weight %) of ethylene-vinyl acetate copolymer after hydrolysis)} / (vinyl acetate content (weight %) of ethylene-vinyl acetate copolymer before hydrolysis)

[0103] (3) Number of fisheyes

[0104] The resin composition layer in the produced film was visually inspected every 500 cm. 2 The number of fish eyes was counted.

[0105] [Example 1]

[0106] 94.6 parts by weight of a composite resin (A1) (composition: 80 parts by weight of polyethylene, 10 parts by weight of polyethylene terephthalate (PET), and 10 parts by weight of nylon 6 (PA6)) formed from recycled materials of used film containers as a thermoplastic resin (A) containing at least two or more components of polyolefins, 5 parts by weight of an ethylene-vinyl acetate copolymer composition (B1) (Melthene SS-A5115 manufactured by Tosoh Corporation, MFR 10 g / 10 min) as a compatibilizer (B), and 0.4 parts by weight of magnesium stearate (C1) as a fatty acid metal salt (C) were used. These were pre-blended using a tumble mixer and then melt-mixed using a twin-screw extruder having a screw diameter of 25 mm (ULTnano25TW manufactured by Technovel) at a resin temperature of 260°C (above the melting temperature of A1, B1, and C1) and a screw speed of 600 rpm. After cooling to room temperature, resin composition pellets (molten mixture) were obtained. The MFR of the resin composition was 1.3 g / 10 minutes.

[0107] Using three types of three-layer microcast molding machines (manufactured by Labtech Engineering), a mixture of the above resin composition pellets and virgin linear low-density polyethylene (LLDPE) (manufactured by Tosoh, density 910 kg / m 3 , MFR 2g / 10min, trade name HF210K) (film composition: virgin LLDPE layer / resin composition layer / virgin LLDPE layer).

[0108] The molding temperature for all three layers was set at 230°C, and the film was pulled at a speed of 2 m / min to produce a film with a width of 50 mm and a total thickness of 110 μm. The thickness of each layer was virgin LLDPE layer / resin composition layer / virgin LLDPE layer = 30 μm / 50 μm / 30 μm.

[0109] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned evaluation method.

[0110] [Example 2]

[0111] 93 parts by weight of a composite resin (A1) (composition: 80 parts by weight of polyethylene, 10 parts by weight of polyethylene terephthalate (PET), and 10 parts by weight of nylon 6 (PA6)) formed from recycled materials of used film containers as a thermoplastic resin (A) containing at least two components of polyolefins, 5 parts by weight of an ethylene-vinyl acetate copolymer composition (B1) (Melthene SS-A5115 manufactured by Tosoh Corporation, MFR 10 g / 10 min) as a compatibilizer (B), and an ethylene-vinyl acetate copolymer saponified product (D1) (Melthene H50 manufactured by Tosoh Corporation, MFR 220 g / 10 min) obtained by saponifying the vinyl acetate component of an ethylene-vinyl acetate copolymer having an ethylene content of 89 mol% and a vinyl acetate content of 11 mol% at a saponification degree of 80 wt% were used. H6822X) as an ethylene-vinyl acetate copolymer saponified product (D), these were pre-blended in a drum mixer and then melt-mixed using a twin-screw extruder with a screw diameter of 25 mm (trade name ULTnano25TW, manufactured by Technovel) at a resin temperature of 260° C. ((above the melting temperature of A1, B1, and D1)) and a screw speed of 600 rpm. The mixture was cooled to room temperature to obtain resin composition pellets (molten mixture). A three-layer film was obtained by the same method as in Example 1 except that the above procedures were followed. The MFR of the resin composition was 1.3 g / 10 min.

[0112] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned method.

[0113] [Example 3]

[0114] A three-layer film was obtained by the same method as in Example 2 except that 2 parts by weight of maleic anhydride-modified polyethylene (B2) (SK Geo Centric Japan, MFR 3 g / 10 min, trade name OREVAC OE825) was used as the compatibilizer (B). The MFR of the resin composition was 0.6 g / 10 min.

[0115] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned method.

[0116] [Example 4]

[0117] A three-layer film was obtained by the same method as in Example 2 except that 2 parts by weight of an ethylene-vinyl acetate copolymer saponified product (D2) (manufactured by Tosoh Corporation, MFR 16 g / 10 min, trade name Melthene H H6410M) was used as the ethylene-vinyl acetate copolymer saponified product (D). The saponified product was obtained by saponifying the vinyl acetate component of an ethylene-vinyl acetate copolymer having an ethylene content of 89 mol% and a vinyl acetate content of 11 mol% at a saponification degree of 40 wt%. The resin composition had an MFR of 1.2 g / 10 min.

[0118] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned method.

[0119] [Example 5]

[0120] A three-layer film was obtained by the same method as in Example 2 except that the molding temperature of all three layers of the three-layer film was 210° C. The MFR of the resin composition was 1.3 g / 10 min.

[0121] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned method.

[0122] [Comparative Example 1]

[0123] A three-layer film was obtained by the same method as in Example 1, except that 100 parts by weight of a composite resin (A1) (composition: 80 parts by weight of polyethylene, 10 parts by weight of polyethylene terephthalate (PET), and 10 parts by weight of polyamide 6 (PA6)) formed from recycled material from used film containers was used as the thermoplastic resin (A) containing at least two components of polyolefins and recycled material from used plastic products. The resin composition pellets were obtained by melt-kneading using a twin-screw extruder with a screw diameter of 25 mm (Technovel, trade name ULTnano25TW) at a resin temperature of 260°C (above the melting temperature of A1) and a screw speed of 600 rpm. The MFR of the resin composition was 1.0 g / 10 min.

[0124] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned evaluation method.

[0125] [Comparative Example 2]

[0126] A three-layer film was obtained by the same method as in Example 1, except that 95 parts by weight of a recycled resin (A1) (composition: 80 parts by weight of polyethylene, 10 parts by weight of polyethylene terephthalate (PET), and 10 parts by weight of polyamide 6 (PA6)) obtained from recycled materials of used plastic products and containing at least two polyolefin components and 5 parts by weight of an ethylene-vinyl acetate copolymer composition (B1) (Melthene SS-A5115 manufactured by Tosoh Corporation, MFR 10 g / 10 min) were pre-blended using a tumble mixer. The mixture was then melt-mixed using a twin-screw extruder with a screw diameter of 25 mm (ULTnano25TW manufactured by Technovel) at a resin temperature of 260°C (above the melting temperature of A1 and B1) and a screw speed of 600 rpm. The mixture was then cooled to room temperature to obtain resin composition pellets (molten mixture). In addition, the MFR of the resin composition was 1.2 g / 10 minutes.

[0127] The number of fisheyes generated in the resin composition layer of the obtained film was measured by the above-mentioned evaluation method.

[0128] [Table 1]

[0129]

[0130] Industrial Applicability

[0131] Films formed from the resin composition of the present invention are useful as packaging containers for foods, daily necessities, industrial parts, pharmaceuticals, office supplies, chemicals, etc., surface protection films, agricultural films such as silage films, heat shrink films, transport bags, etc.

Claims

1. A resin composition comprising: 70 parts by weight or more and 98.99 parts by weight or less of two or more thermoplastic resins (A) derived from recycled materials of used plastic products and containing at least polyolefin; 1 part by weight or more and 29.99 parts by weight or less of a compatibilizer (B); and 0.01 parts by weight or more and 5 parts by weight or less of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D), in, The total amount of (A), (B), and (C) and / or (D) is 100 parts by weight.

2. The resin composition according to claim 1, wherein The thermoplastic resin (A) contains at least one resin selected from polyester, polyamide, and ethylene-vinyl alcohol copolymer as a component other than polyolefin.

3. The resin composition according to claim 2, wherein The polyester is polyethylene terephthalate, and the polyamide is nylon 6 or nylon 66.

4. The resin composition according to claim 1, wherein The compatibilizer (B) is ethylene-vinyl acetate copolymer and / or maleic anhydride-modified polyolefin.

5. The resin composition according to claim 1, wherein The fatty acid metal salt (C) is at least one selected from stearates of magnesium, calcium or zinc, and hydroxystearates. The resin composition according to claim 1 , wherein The ethylene-vinyl acetate copolymer saponified product (D) is a saponified product of an ethylene-vinyl acetate copolymer having an ethylene content of 75 mol% to 95 mol% and a vinyl acetate content of 5 mol% to 25 mol%. The degree of saponification of the vinyl acetate component is 20% by weight or more.

7. The resin composition according to claim 1, wherein The melt flow rate of the saponified ethylene-vinyl acetate copolymer (D) measured at 190° C. and a load of 2160 g in accordance with JIS K6924-1 is 40 g / 10 minutes or more.

8. The resin composition according to claim 1, wherein The used plastic product is at least one selected from the group consisting of food packaging containers, sanitary product packaging containers, cosmetic packaging containers, and daily necessities packaging containers. 9 . A film comprising the resin composition according to claim 1 . 10 . A multilayer film comprising at least one layer formed from the resin composition according to claim 1 .

11. A packaging container comprising the film according to claim 9.

12. A packaging container comprising the film according to claim 10.

13. A method for producing a film, which is a method for producing the film according to claim 9, the method comprising: The resin composition according to any one of claims 1 to 8 is molded at 190°C to 250°C.

14. A method for manufacturing a multilayer film, which is a method for manufacturing the multilayer film according to claim 10, the method comprising: The resin composition according to any one of claims 1 to 8 is molded at 190°C to 250°C.

15. A method for producing a resin composition, comprising the step of obtaining a molten mixture, wherein: The molten mixture comprises: 70 parts by weight or more and 98.99 parts by weight or less of two or more thermoplastic resins (A) derived from recycled materials of used plastic products and containing at least polyolefin; 1 part by weight or more and 29.99 parts by weight or less of a compatibilizer (B); and 0.01 parts by weight or more and 5 parts by weight or less of a fatty acid metal salt (C) and / or an ethylene-vinyl acetate copolymer saponified product (D).

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