Recycled resin composition and film using the same resin composition

Abstract

The aim is to improve the physical properties of PCR resin while maintaining a high recycling rate by combining PCR resin derived from household waste and PIR resin, which have previously had limited applications, thereby developing new recycling applications for PCR resin and promoting resource circulation. [Solution] A resin composition containing 20 to 99 parts by weight of post-consumer recycled resin (PCR resin) mainly composed of polyolefin, and 1 to 80 parts by weight of post-industrial recycled resin (PIR resin) mainly composed of polyolefin (total of PCR resin and PIR resin is 100 parts by weight).

Description

Technical Field

[0001] The present invention relates to a resin composition containing a post-consumer recycled resin mainly composed of polyolefin and a post-industrial recycled resin mainly composed of polyolefin.

Background Art

[0002] In recent years, due to concerns about environmental pollution problems caused by plastics, the importance of recycling plastic products has been increasing.

[0003] Among recycling methods, material recycling is considered the most desirable treatment method from the viewpoints of resource saving, energy saving, and economy. Material recycling includes post-consumer recycled resin (hereinafter referred to as PCR resin) that recycles used products discharged from consumers and post-industrial recycled resin (hereinafter referred to as PIR resin) that recycles molding losses generated in plastic molding factories. Among PCR resins, there are various types such as resins obtained by recycling household appliances waste and resins obtained by recycling used foam trays. In particular, PCR resin obtained by collecting and recycling household waste, which is generated in large quantities, can be said to be an important recycling method and product in the domestic waste treatment process. On the other hand, PCR resin derived from household waste has extremely low physical properties, and therefore has the problem that its applicable uses are limited. The causes of the deterioration of physical properties are also various, such as a case where the polymer simply deteriorates and contains a large amount of low molecular weight components, and a case where the physical properties deteriorate due to insufficient compatibility caused by the inclusion of a plurality of resins. Therefore, although PCR resin derived from household waste is used in limited applications such as pallets and artificial trees, it cannot be used in full in these applications, and a large amount of it is diverted to thermal recycling or exported abroad. To solve these problems, it is necessary to expand the output applications, and for this purpose, it is necessary to improve the physical properties of PCR resin.

[0004] Patent Document 1 describes a study on improving the mechanical properties and moldability of PCR resin by combining the incorporation of a highly flexible random alpha-olefin copolymer with a method for imparting fluidity. While this method is expected to improve the physical properties of PCR resin and expand its applications, it necessitates the addition of virgin resin, thus reducing the recycling rate.

[0005] Patent Document 2 focuses on dispersing polyethylene, polypropylene, and polystyrene contained in PCR resin, and studies have been conducted to improve physical properties by adding a modifier consisting of a styrene-based thermoplastic elastomer and calcium carbonate as a compatibilizer. Although results have been obtained in which physical properties can be improved by adding this modifier, it is still necessary to add several tens of percent of the virgin modifier material in order to obtain sufficient physical properties, which leads to a decrease in the recycling rate.

[0006] Furthermore, there are few examples of PCR resin being considered for recycling into film products, which are a major application in the current plastics industry. This is likely because thinner films require higher mechanical properties and greater molding stability.

[0007] On the other hand, PIR resins are easier to manage during disposal, resulting in recycled resins with relatively good physical properties and moldability. In particular, PIR resins made from single-material waste are recognized as superior recycled resins due to their excellent physical properties and relatively stable quality, and there are few restrictions on the applications of the output. However, PIR resins obtained by recycling dissimilar composite materials such as multilayer films are difficult to recycle and tend to have lower transparency and mechanical properties compared to single-material PIR resins, thus limiting their applications. Nevertheless, it is a fact that a large amount of molding loss is generated from dissimilar composite materials, and expanding the uses of these PIR resins is important when considering future resource circulation. [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2024-500675 [Patent Document 2] Japanese Patent Publication No. 2007-291213 [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention aims to improve the physical properties of PCR resin while maintaining a high recycling rate by combining PCR resin and PIR resin, which have previously had limited applications, thereby developing new recycling applications for PCR resin and promoting resource circulation. [Means for solving the problem]

[0010] As a result of diligent research to solve the aforementioned problems, the inventors of the present invention have found that a resin composition obtained by blending a post-consumer recycled resin (PCR resin) mainly composed of polyolefin obtained by recycling household waste and a post-industrial recycled resin (PIR resin) mainly composed of polyolefin exhibits excellent film properties, and have completed the present invention.

[0011] In other words, the embodiments of the present invention are as follows [1] to

[11] . [1] A resin composition comprising 20 to 99 parts by weight of post-consumer recycled resin (PCR resin) mainly composed of polyolefin, and 1 to 80 parts by weight of post-industrial recycled resin (PIR resin) mainly composed of polyolefin (total of PCR resin and PIR resin is 100 parts by weight). [2] The resin composition according to [1], wherein the post-consumer recycled resin (PCR resin) is a resin obtained by collecting waste discharged from households and recycling the waste containing polyolefins from said waste. [3] The resin composition according to any one of [1] to [2], wherein the post-consumer recycled resin (PCR resin) contains 70 to 100 parts by weight of polyethylene and / or polypropylene when the PCR resin is 100 parts by weight. [4] The resin composition according to any one of [1] to [3], wherein the post-industrial recycled resin (PIR resin) is a resin obtained by recycling different multilayer films. [5] The resin composition according to any one of the claims [1] to [4], wherein the post-industrial recycled resin (PIR resin) comprises 70 to 99 parts by weight of polyolefin and 1 to 30 parts by weight of a resin other than polyolefin when the PIR resin is 100 parts by weight. [6] The resin composition according to any one of [1] to [5], wherein the post-industrial recycled resin (PIR resin) comprises 70 to 99 parts by weight of polyolefin and 1 to 30 parts by weight of polyamide resin and / or polyester resin when the PIR resin is 100 parts by weight. [7] The resin composition according to any one of the claims [1] to [6], wherein the polyolefin of the post-industrial recycled resin (PIR resin) is polyethylene. [8] The resin composition according to any one of [1] to [7], wherein the Vicat softening temperature of the post-industrial recycled resin (PIR resin) is 50°C or more and 100°C or less. [9] The resin composition according to any one of the claims [1] to [8], wherein the post-industrial recycled resin (PIR resin) is a resin that has been recycled with the addition of a compatibilizer. A molded article comprising the resin composition described in any one of the items [1] to [9]. A film comprising the resin composition described in any one of the items [1] to [9]. [Effects of the Invention]

[0012] The film made of the resin composition which is one aspect of the present invention has excellent physical properties and is useful for molded articles that require these physical properties. In addition, since the recycling ratio is high, it contributes to the promotion of resource circulation.

Mode for Carrying Out the Invention

[0013] Hereinafter, the present invention will be described in detail according to its preferred embodiments.

[0014] The resin composition which is one aspect of the present invention contains 20 to 99 parts by weight of a post-consumer recycled resin (PCR resin) mainly composed of polyolefin and 1 to 80 parts by weight of a post-industrial recycled resin (PIR resin) mainly composed of polyolefin.

[0015] The post-consumer recycled resin mainly composed of polyolefin (hereinafter referred to as PCR resin) refers to the resin obtained by a scheme for recycling plastic products used and discarded by consumers. That is, it is the resin obtained by a recycling process in which waste discharged from households is collected, washed, pulverized, and pelletized by an extruder. The PCR resin may be obtained by collecting household waste and pelletizing it as it is, or by material sorting or the like. Since it has excellent physical properties, it is preferable to perform sorting or the like. Examples of the material sorting method include specific gravity sorting and optical sorting.

[0016] The PCR resin only needs to contain polyolefin as the main component, and may contain resins other than polyolefin. Examples of the polyolefin include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, and ethylene-propylene copolymer. Among these, high-density polyethylene, low-density polyethylene, and linear low-density polyethylene are preferable as the polyolefin.

[0017] Examples of resins other than polyolefins include polyamide resins, polyester resins, polystyrene resins, polycarbonate resins, styrene-acrylonitrile copolymers, acrylic resins, ethylene-vinyl alcohol copolymers, polyvinyl chloride resins, and the like. These may be included alone as a polyolefin component or may be included in a plurality of types.

[0018] As the ratio of the resin constituting the PCR resin, it is preferable that the polyolefin is 70 to 100 parts by weight and the resin other than the polyolefin is 0 to 30 parts by weight, and more preferably that the polyolefin is 80 to 99 parts by weight and the resin other than the polyolefin is 1 to 20 parts by weight. Note that the total of the polyolefin and the resin other than the polyolefin is 100 parts by weight.

[0019] In addition, the PCR resin may contain impurities other than the resin component. Impurities refer to both substances intentionally added in the process of obtaining the PCR resin and substances unintentionally mixed into the PCR resin.

[0020] For example, examples of impurities that may be present in the PCR resin include, but are not limited to, inorganic fillers, antioxidants, acid acceptors, anti-foaming agents, tackifiers, light stabilizers, ultraviolet absorbers, anti-blocking agents, plasticizers, waxes, cross-linking agents, mold release agents, antistatic agents, antibacterial agents, flame retardants, pigments, dyes, paper, synthetic and natural fibers, adhesives, or combinations thereof.

[0021] Examples of inorganic fillers include talc, carbon black, calcium carbonate, titanium oxide, mica, barite, kaolin, silica, glass fiber, and the like.

[0022] Examples of antioxidants include phenolic antioxidants and phosphorus-based antioxidants.

[0023] Examples of acid acceptors include, but are not limited to, calcium stearate, sodium stearate, zinc stearate, magnesium oxide and zinc oxide, synthetic hydrotalcite, lactate and lactylate, epoxy compounds, or combinations thereof.

[0024] Antifoaming agents are substances that suppress foaming caused by moisture, and examples include calcium oxide.

[0025] The melt mass flow rate (MFR) of the PCR resin is not particularly limited, but it is preferable that the MFR measured under conditions of 190°C and a 2.16 kg load be 0.1 g / 10 min to 30 g / 10 min, more preferably 0.5 g / 10 min to 20 g / 10 min, and most preferably 0.5 g / 10 min to 10 g / 10 min. An MFR of 0.1 g / 10 min or higher is preferable because it does not easily increase the extrusion load when producing PCR resin pellets in an extruder, resulting in excellent productivity. An MFR of 30 g / 10 min or lower is preferable because it provides excellent tensile stability of the strands when producing PCR resin pellets in an extruder.

[0026] Post-industrial recycled resin (hereinafter referred to as PIR resin) is, without any particular limitations, a resin that is collected from plastic molding plants as in-process waste, burrs, and substandard products, recycled, and then pelletized again.

[0027] The PIR resin may be a single material or a composite of different materials, and may be made from recycled waste such as containers, injection plates, and films, but a resin made from recycled multilayer films of different materials is preferred.

[0028] The PIR resin obtained from dissimilar multilayer films preferably contains polyolefin as its main component and also contains resins other than polyolefin.

[0029] Examples of polyolefins include high-density polyethylene, low-density polyethylene, linear low-density polyethylene, polypropylene, and ethylene-propylene copolymers. These may be included individually or in combination. Among these, high-density polyethylene, low-density polyethylene, and linear low-density polyethylene are preferred as polyolefins, with the inclusion of linear low-density polyethylene being the most preferred. Including linear low-density polyethylene improves the mechanical properties of the resulting resin composition obtained by blending the PIR resin and PCR resin. Furthermore, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, and 1-octene can be used as comonomers for linear low-density polyethylene, with 1-hexene, 1-octene, and 4-methyl-1-pentene being preferred due to their excellent mechanical properties. In addition, the resin density is 870 kg / m³ due to its excellent mechanical properties. 3 More than 910kg / m 3 The following is preferable, and more preferably, the resin density is 870 kg / m³. 3 More than 900kg / m 3 The following applies:

[0030] Furthermore, while not particularly limited, resins other than polyolefins include polyamide resins, polyester resins, polystyrene resins, and ethylene-vinyl alcohol copolymers, and among these, polyamide resins and polyester resins are preferred.

[0031] Examples of polyamide resins include nylon 6, nylon 6,6, nylon 11, nylon 12, and poly(metaxylylene adipamide).

[0032] Examples of polyester resins include polyethylene terephthalate, glycol-modified polyethylene terephthalate resin (PETG resin), polybutylene terephthalate, and polylactic acid.

[0033] Among these, nylon 6 and polyethylene terephthalate are preferred resins other than polyolefins included in the PIR resin.

[0034] The resin composition of the PIR resin obtained by recycling dissimilar multilayer films is preferably 70 to 99 parts by weight of polyolefin and 1 to 30 parts by weight of resin other than polyolefin, and more preferably 80 to 99 parts by weight of polyolefin and 1 to 20 parts by weight of resin other than polyolefin. The total of polyolefin and non-polyolefin resin is 100 parts by weight.

[0035] PIR resins obtained from dissimilar multilayer films may contain compatibilizers to improve their moldability and physical properties.

[0036] The compatibilizer is not particularly limited and can be any agent that can improve the physical properties of the PIR resin, but examples include ethylene-vinyl acetate copolymer, acid-modified polyolefin, ethylene-glycidyl methacrylate copolymer, ionomer resin, oxazoline group-containing resin, and preferably at least one selected from the group consisting of ethylene-vinyl acetate copolymer, maleic anhydride-modified polyethylene, and ethylene-glycidyl methacrylate copolymer.

[0037] The ethylene-vinyl acetate copolymer may also be an ethylene-vinyl acetate copolymer composition containing multiple types of ethylene-vinyl acetate copolymers with different vinyl acetate content. In this case, ethylene From the viewpoint of compatibility, it is preferable to have three or more types of ethylene vinyl acetate copolymers. Furthermore, from the viewpoint of compatibility, an ethylene vinyl acetate copolymer mixture containing multiple types of ethylene vinyl acetate copolymers is preferable. When the product is considered as 100% by weight, the difference in vinyl acetate content of each ethylene vinyl acetate copolymer is preferably 40% by weight or less, and more preferably the difference in vinyl acetate content of at least one set of ethylene vinyl acetate copolymers is 5% by weight or more.

[0038] The melt mass flow rate (MFR) of the PIR resin measured under conditions of 190°C and a 2.16 kg load is not particularly limited, but is preferably 0.5 g / 10 min to 30 g / 10 min, more preferably 0.8 g / 10 min to 20 g / 10 min, and most preferably 1 g / 10 min to 10 g / 10 min, as this provides excellent film moldability.

[0039] Furthermore, the Vicat softening temperature of the PIR resin, as measured in accordance with JIS K7206, is preferably 50°C to 100°C, more preferably 60°C to 95°C, and most preferably 70°C to 90°C. When the Vicat softening temperature is 50°C or higher, the resin composition obtained by blending with PCR has a high elastic modulus, resulting in a recyclable product with good rigidity, which is preferable. When the Vicat softening temperature is 100°C or lower, the toughness of the resin composition obtained by blending with PCR is improved, resulting in a recyclable product with excellent mechanical properties, which is also preferable.

[0040] The mixing ratio of PCR resin and PIR resin in the resin composition is 20 to 99 parts by weight of PCR and 1 to 80 parts by weight of PIR resin, more preferably 30 to 90 parts by weight of PCR resin and 10 to 70 parts by weight of PIR resin, and most preferably 50 to 80 parts by weight of PCR resin and 20 to 50 parts by weight of PIR resin. The total amount of PCR resin and PIR resin is 100 parts by weight.

[0041] When the amount of PCR resin is 20 parts by weight or more, it is preferable because the effective utilization rate of the PCR resin is high, and when it is 99 parts by weight or less, it is preferable because a recycled product with excellent mechanical properties can be obtained. Furthermore, when the amount of PIR resin is 1 part by weight or more, it is preferable because it has excellent mechanical properties, and when it is 80 parts by weight or less, it is preferable because the effective utilization rate of the PCR resin is high.

[0042] Furthermore, the resin composition may contain virgin resin as needed, but the ratio of PCR resin to PIR resin (recycled resin) (the ratio after subtracting the virgin resin content) is preferably 80% by weight or more, more preferably 90% by weight or more, and most preferably 95% by weight or more, due to its significant contribution to resource recycling.

[0043] The method for producing the resin composition is not particularly limited as long as the PCR resin and PIR resin can be uniformly dispersed. For example, the PCR resin and PIR resin pellets may be blended together and directly fed into an extruder such as a film molding machine (hereinafter referred to as the dry blend method), or the PCR resin and PIR resin may be melt-kneaded together to produce a blended resin (hereinafter referred to as the melt blend method), which may then be fed into a molding machine such as a film molding machine for use.

[0044] In the dry blending method, the pellets can be pre-blended using a Henschel mixer or tumbler before use.

[0045] In the melt blending method, examples of blending methods include using kneading equipment such as a single-screw extruder, twin-screw extruder, multi-screw extruder, Banbury mixer, pressure kneader, rotary roll, and internal mixer. Among these, single-screw and twin-screw extruders are preferred due to their excellent dispersibility and continuous production capabilities.

[0046] When mixing with a twin-screw extruder, the screw rotation speed is not particularly limited, but it is preferable to mix at 50 rpm to 3000 rpm, and more preferably at 150 rpm to 1000 rpm. A screw rotation speed of 50 rpm or higher is preferable because it improves the dispersibility of each mixed component and results in a resin with excellent physical properties. A screw rotation speed of 3000 rpm or lower is also preferable because it prevents deterioration of the resin due to excessive shear heat, resulting in a resin with excellent physical properties. When using the melt blend method, the mixing temperature is preferably 160°C to 300°C.

[0047] Furthermore, the resin composition may be intentionally modified to the extent that it does not impair the effects of the present invention, by adding acid absorbers, foam inhibitors, antistatic agents, light stabilizers, ultraviolet absorbers, nucleating agents, antioxidants, blocking inhibitors, flow improvers, mold release agents, flame retardants, colorants, inorganic neutralizing agents, filler conductive agents, chain length extenders, hydrolysis inhibitors, etc.

[0048] Furthermore, the resin composition can be used in any form, such as pellets or powder.

[0049] A molded article according to one aspect of the present invention is obtained by molding a resin composition. The molding method is not particularly limited, but examples include shape extrusion, film, sheet, blow molding, injection molding, foaming, extrusion coating, and rotational molding. Among these, film is preferred because it offers excellent moldability for the resin composition.

[0050] There are no particular restrictions on the film forming method, and examples include inflation molding, co-extrusion inflation molding, T-die molding, co-extrusion T-die molding, calendering, and compression molding. Among these, inflation molding, co-extrusion inflation molding, T-die molding, and co-extrusion T-die molding are preferred due to their superior productivity. Furthermore, the film may be laminated with other films, and similarly there are no particular restrictions on the lamination method, but examples include dry lamination, extrusion lamination, and sandwich lamination.

[0051] A film according to one aspect of the present invention can be obtained by forming the above resin composition into a film. The film made of the above resin composition may be a single layer or can be used as a multilayer film. The lamination structure of the multilayer film is not particularly limited, but for example, it may include not only the resin composition (I) layer but also layers made of other components, such as a virgin resin layer (II), an adhesive layer (III), or a barrier layer (IV). Specifically, examples include (I) / (II), (II) / (I) / (II), (I) / (III) / (IV) / (III) / (I), (I) / (III) / (IV) / (III) / (II), etc. The thickness of the film made of the above resin composition is not particularly limited, but from the viewpoint of mechanical strength, it is preferably 10 μm to 300 μm.

[0052] The film molding temperature is preferably in the range of 160°C to 250°C, more preferably in the range of 160°C to 230°C, and even more preferably in the range of 160°C to 200°C. A molding temperature of 160°C or higher is preferable because it reduces the occurrence of fish eyes, and a temperature of 250°C or lower is preferable because it provides excellent film moldability.

[0053] Furthermore, when using PCR resin for film applications, it is preferable to remove coarse foreign matter by extruding it once in an extruder equipped with a filter before feeding it into a film molding machine. There are no particular restrictions on the type of extruder used, and single-screw or twin-screw extruders can be used as examples. There are also no restrictions on the type of filter, and screen meshes or laser filters can be used as examples. There are also no restrictions on the mesh size of the filter, and examples include 30 mesh (mesh size: 510-630 μm), 50 mesh (mesh size: 290-370 μm), 60 mesh (mesh size: 240-280 μm), 80 mesh (mesh size: 180-220 μm), 100 mesh (mesh size: 140-150 μm), 200 mesh (mesh size: 80 μm), and 400 mesh (mesh size: 35 μm). Among these, it is preferable to use a mesh size of 80 mesh or more and 400 mesh or less, and more preferable to use a mesh size of 100 mesh or more and 200 mesh or less. Using a mesh of 80 mesh or higher is preferable because it reduces the occurrence of holes in the film caused by foreign matter during film formation, while using a mesh of 400 mesh or lower is preferable because it reduces the increase in resin pressure due to foreign matter clogging during extrusion.

[0054] The above film is useful as packaging for garbage bags, daily necessities, industrial parts, pharmaceuticals, office supplies, chemical products, etc., as well as for surface protection films, shrink films, transport bags, and more. [Examples]

[0055] The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these. (1) Meltmass flow rate (MFR) The MFR of the resin used in this example was measured using a melt indexer (manufactured by Takara Kogyo Co., Ltd.) at 190°C and under a load of 2.16 kg. (2) Density The density of the resin used in this example was measured in accordance with JIS K7112. (3) Vicat softening temperature The Vicat softening temperature of the resin used in this example was measured in accordance with JIS K7206. (4) Tensile properties The physical properties of the fabricated film in the MD direction (parallel to the film forming flow) and TD direction (perpendicular to the film forming flow) were measured using a tensile testing machine. The film was punched out in both the MD and TDh directions using dumbbell test pieces measuring 10 mm wide x 100 mm long, and measured using a Tensilon tensile testing machine (Orientec, RTE-1210) under the conditions of a chuck distance of 30 mm and a tensile speed of 200 mm / min. The stress and elongation at the point of fracture (elongation at fracture [%] = tensile length required to fracture [mm] / chuck distance of 30 mm) were measured. [Example 1] The post-consumer recycled resin (PCR resin), primarily composed of polyolefins, was obtained by sorting (optical sorting, specific gravity sorting), washing, crushing, melt extrusion, and pelletizing household waste collected from the city using a recycler's equipment. Analysis of the composition of this PCR resin (A1) revealed the following: polyethylene (PE): 78% by weight, polypropylene (PP): 12% by weight, polystyrene (PS): 5% by weight, nylon 6 (PA): 1% by weight, polyethylene terephthalate (PET): 1% by weight, and inorganic matter: 3% by weight. The MFR (Metal Fluid Ratio) was 0.6 g / 10 mins. This PCR resin was extruded at 230°C using a single-screw extruder with a 100-mesh screen mesh installed in the die, and coarse foreign matter was removed before use.

[0056] The post-industrial recycled resin (PIR resin), primarily composed of polyolefin, was obtained by recovering trimming loss from multilayer films produced by a film manufacturer for food packaging films, crushing, granulating, and twin-screw extrusion to produce pellets. During the twin-screw extrusion process, 5% by weight of an ethylene-vinyl acetate copolymer compatibilizer (manufactured by Tosoh, MFR 10g / 10min, trade name Mersen® S A-5115) was added relative to the trimming loss. Twin-screw extrusion was performed at 250°C. The resulting PIR resin (B1) had an MFR of 4.0g / min and a density of 950kg / m³. 3The resin composition was PE: 85% by weight, PA: 5% by weight, PET: 5% by weight, compatibilizer: 5% by weight, and the Vicat softening temperature was 75°C. The PE in this PIR resin contained linear low-density PE with 1-hexene as a comonomer.

[0057] 90 parts by weight of PCR resin (A1) and 10 parts by weight of PIR resin (B1) were used. These were pre-blended in a tumbler mixer, and then the blended resins were fed into the extruder of a cast film molding machine (manufactured by the Plastics Engineering Research Institute) to form a film. The cast film molding was performed at an extrusion temperature of 180°C, a cooling roll temperature of 30°C, a take-up speed of 4.0 m / min, a film width of 250 mm, and a film thickness of 30 μm.

[0058] The tensile properties of the obtained film were measured using the evaluation method described above. Furthermore, since the blended PIR resin (B1) contained 5% by weight of virgin compatibilizer, the recycling rate of this film was 99.5% by weight. The evaluation results are shown in Table 1. [Example 2] A single-layer film was obtained using the same method as in Example 1, except that 80 parts by weight of PCR resin (A1) and 20 parts by weight of PIR resin (B1) were used.

[0059] Table 1 shows the tensile properties and recycling rate of the obtained films. [Example 3] A single-layer film was obtained using the same method as in Example 1, except that 70 parts by weight of PCR resin (A1) and 30 parts by weight of PIR resin (B1) were used.

[0060] Table 1 shows the tensile properties and recycling rate of the obtained films. [Example 4] A single-layer film was obtained using the same method as in Example 1, except that 50 parts by weight of PCR resin (A1) and 50 parts by weight of PIR resin (B1) were used.

[0061] Table 1 shows the tensile properties and recycling rate of the obtained films. [Example 5] A single-layer film was obtained using the same method as in Example 1, except that 30 parts by weight of PCR resin (A1) and 70 parts by weight of PIR resin (B1) were used.

[0062] Table 1 shows the tensile properties and recycling rate of the obtained films. [Example 6] As the PIR resin, we used pellets obtained by recovering trimming loss from multilayer films produced by a film manufacturer for food packaging films, crushing, granulating, and twin-screw extrusion. During the twin-screw extrusion process, 5% by weight of an ethylene-vinyl acetate copolymer compatibilizer (manufactured by Tosoh, MFR 10g / 10min, trade name Mersen® S A-5115) was added relative to the trimming loss. Twin-screw extrusion was performed at 250°C. The resulting PIR resin (B2) had an MFR of 4.0g / min and a density of 970kg / m³. 3 The resin composition was PE: 85% by weight, PET: 10% by weight, compatibilizer: 5% by weight, and the Vicat softening temperature was 105°C. Furthermore, the PE in this PIR resin contained only linear low-density PE with 1-butene as a comonomer; it did not contain linear low-density PE with 1-hexene or 1-octene as comonomers. A single-layer film was obtained using the same method as in Example 1, except that 70 parts by weight of PCR resin (A1) and 30 parts by weight of PIR resin (B2) were used.

[0063] Table 1 shows the tensile properties and recycling rate of the obtained films. [Example 7] A single-layer film was obtained using the same method as in Example 1, except that 50 parts by weight of PCR resin (A1) and 50 parts by weight of PIR resin (B2) were used.

[0064] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 1] A single-layer film was obtained using the same method as in Example 1, except that 100 parts by weight of PCR resin (A1) were used.

[0065] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 2] 90 parts by weight of PCR resin (A1), and as virgin PE, linear low-density polyethylene (manufactured by Tosoh, comonomer: 1-hexene, MFR 2.0 g / 10 min, density 910 kg / m³). 3 A single-layer film was obtained by the same method as in Example 1, except that 10 parts by weight of product name Nipolon (registered trademark) Z HF210K)(C1) was used, with a Vicat softening temperature of 97°C.

[0066] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 3] A single-layer film was obtained using the same method as in Example 1, except that 70 parts by weight of PCR resin (A1) and 30 parts by weight of linear low-density polyethylene (C1) as virgin PE were used.

[0067] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 4] A single-layer film was obtained using the same method as in Example 1, except that 50 parts by weight of PCR resin (A1) and 50 parts by weight of linear low-density polyethylene (C1) as virgin PE were used.

[0068] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 5] PCR resin (A1) is 70 parts by weight, and as virgin PE is linear low-density polyethylene (manufactured by Tosoh, comonomer: 1-butene, MFR 1.1 g / 10 min, density 920 kg / m³). 3 A single-layer film was obtained by the same method as in Example 1, except that 30 parts by weight of product name Nipolon (registered trademark) L F21)(C2) was used, with a Vicat softening temperature of 101°C.

[0069] Table 1 shows the tensile properties and recycling rate of the obtained films. [Comparative Example 6] A single-layer film was obtained using the same method as in Example 1, except that 50 parts by weight of PCR resin (A1) and 50 parts by weight of linear low-density polyethylene (C2) as virgin PE were used.

[0070] Table 1 shows the tensile properties and recycling rate of the obtained films.

[0071] [Table 1] [Industrial applicability]

[0072] The resin composition of the present invention is useful for molded articles, especially films, and is useful as packaging containers for garbage bags, daily necessities, industrial parts, pharmaceuticals, office supplies, chemical products, etc., as well as surface protection films, shrink films, transport bags, and the like.

Claims

1. A resin composition containing 20 to 99 parts by weight of post-consumer recycled resin (PCR resin) mainly composed of polyolefin, and 1 to 80 parts by weight of post-industrial recycled resin (PIR resin) mainly composed of polyolefin (total of PCR resin and PIR resin is 100 parts by weight).

2. The resin composition according to claim 1, wherein the post-consumer recycled resin (PCR resin) is a resin obtained by collecting waste discharged from households, selecting waste containing polyolefins from said waste, and recycling it.

3. The resin composition according to claim 1, wherein the post-consumer recycled resin (PCR resin) contains 70 to 100 parts by weight of polyolefin when the PCR is 100 parts by weight.

4. The resin composition according to claim 1, wherein the post-industrial recycled resin (PIR resin) is a resin obtained by recycling different multilayer films.

5. The resin composition according to claim 1, wherein the post-industrial recycled resin (PIR resin) comprises 70 to 99 parts by weight of polyolefin and 1 to 30 parts by weight of a resin other than polyolefin, based on 100 parts by weight of PIR resin.

6. The resin composition according to claim 1, wherein the post-industrial recycled resin (PIR resin) comprises 70 to 99 parts by weight of polyolefin and 1 to 30 parts by weight of polyamide resin and / or polyester resin when the PIR resin is 100 parts by weight.

7. The resin composition according to claim 1, wherein the polyolefin of the post-industrial recycled resin (PIR resin) is polyethylene.

8. The resin composition according to claim 1, wherein the Vicat softening temperature of the post-industrial recycled resin (PIR resin) is 50°C or higher and 100°C or lower.

9. The resin composition according to claim 1, wherein the post-industrial recycled resin (PIR resin) is a recycled resin containing a compatibilizer.

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

11. A film comprising the resin composition according to any one of claims 1 to 10.

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