Adhesive resin composition, laminated sheet and lid material using the same

Abstract

To provide an adhesive resin composition that exhibits good moldability, ease of opening, and stringing properties regardless of the coating speed, and a laminated sheet and lid material having a film of the adhesive resin composition laminated on it. [Solution] An adhesive resin composition comprising polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D), with each component having a content of 40-80% by mass of polyethylene resin (A), 0-25% by mass of wax (B), 15-40% by mass of polyolefin resin (C), and 1-15% by mass of layered inorganic filler (D) in a total of 100% by mass, wherein the polyolefin resin (C) is a polypropylene resin or a polybutene resin, and the wax (B) is polyethylene wax or Fischer-Tropsch wax.

Description

Technical Field

[0001] The present invention relates to an adhesive resin composition exhibiting good peelability, a laminated sheet having a film of the adhesive resin composition laminated thereon, and a lid material.

Background Art

[0002] In the field of food packaging, until now, a packaging form has been widely used in which contents such as cup ramen, yogurt, and snack foods are filled into a polyethylene container or a container coated with polyethylene, and a lid material having an adhesive resin composition laminated on the innermost layer is adhered to the opening of the container.

[0003] When opening the lid material from the container, in order to impart a peelability function, cohesive failure is the mainstream in the layer of the adhesive resin composition. Cohesive failure is caused by the formation of a sea-island structure by two incompatible or partially compatible components constituting the adhesive resin composition, which results in a smooth peeling feeling and exhibits peelability. However, depending on the shape of the island phase of the sea-island structure, "thread dragging" may occur in which the adhesive resin composition remains in a filamentous form on the flange of the container.

[0004] So far, studies have been made to improve thread dragging. For example, a peelable laminated film obtained by sequentially laminating a base material layer, an intermediate layer, and a sealant layer, wherein the sealant layer is a thermoplastic resin A selected from the group consisting of a polyethylene resin, an ethylene-methacrylic acid copolymer resin, and a polypropylene resin, and a thermoplastic resin B selected from polybutene-1, polypropylene, or an ethylene-propylene random copolymer, and is composed of a resin composition containing them in a mass ratio of thermoplastic resin A / thermoplastic resin B = 70 / 30 to 97 / 3, and has a sea-island structure in which domains composed of the thermoplastic resin B are dispersed in the thermoplastic resin A phase, and the ratio of the major axis to the minor axis of the cross-section of the domain is major axis / minor axis = 14 to 30, and the thickness of the sealant layer is 3 to 15 μm. A peelable laminated film has been proposed (see Patent Document 1).

[0005] Furthermore, an adhesive resin composition comprising a polymer (A) having a DSC melting point of 80 to 155°C and a wax (B) grafted with styrene monomer has been proposed, characterized in that the polymer (A) contains at least one selected from the group consisting of polyethylene resins, polypropylene resins, and polybutene resins, the viscosity of the wax (B) at 140°C is 10 to 3000 mPa·s, and the composition satisfies one of the following: (1) In 100% by mass of the adhesive resin composition, the content of polymer (A) is 70 to 95% by mass and the content of wax (B) is 5 to 30% by mass; (2) In 100% by mass of the adhesive resin composition, the content of polymer (A) is 50 to 95% by mass, the content of wax (B) is 5 to 30% by mass and the content of inorganic filler (C) is 1 to 40% by mass (see Patent Document 2). [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2013-136151 [Patent Document 2] Japanese Patent Publication No. 2024-070203 [Overview of the project] [Problems that the invention aims to solve]

[0007] Generally, adhesive resin compositions are molded and laminated onto a substrate using two molding methods: the T-die method and the inflation method. The T-die method is a molding method in which molten adhesive resin composition is poured and pulled with a roll to create a thin film. When pulled with the roll, strain is generated in the molten adhesive resin composition, and the island phases are stretched into an elliptical shape as they solidify. The faster the molding speed, the more elongated the ellipses of the island phases become, and eventually the sea phase and island phases form a mille-feuille-like layer. Due to the formation of this mille-feuille-like layer, when the lid material is opened from the container, each layer stretches and breaks, which is considered to be one of the causes of stringing. On the other hand, the inflation method is a molding method in which a molten adhesive resin composition is blown up and inflated with air like a balloon to form a thin film. Because the inflation method with air does not cause much strain on the adhesive resin composition, the island phase tends to maintain an elliptical shape regardless of the molding conditions, and as a result, stringing is less likely to occur. For these reasons, the T-die method tends to produce stringing more easily than the inflation method depending on the molding conditions. The composition proposed in Patent Document 1 improves stringing by controlling the ratio of the major axis to the minor axis of the island phase (domain) cross-section. However, according to the inventors' studies, stringing does not occur up to a molding speed of 80 m / min in the T-die method, but when the coating speed is increased to 150 m / min, a mille-feuille-like layer is formed, making stringing more likely. The composition proposed in Patent Document 2 improves stringing in paper / PE by using at least one resin selected from the group consisting of polyethylene resin, polypropylene resin, and polybutene resin, a wax grafted with styrene monomer, and an inorganic filler. However, due to the inclusion of a wax grafted with styrene monomer, which has poor compatibility with the resin, and an excessive amount of inorganic filler, increasing the coating speed in the T-die method causes increased strain, resulting in holes and making molding impossible.

[0008] The problem that the present invention aims to solve is to provide an adhesive resin composition that exhibits good moldability, ease of opening, and stringing properties regardless of the coating speed (molding conditions), and a laminated sheet and lid material having a film of the adhesive resin composition laminated on it. [Means for solving the problem]

[0009] The inventors of the present invention conducted intensive studies to solve the above problems and found that the above problems can be solved by including polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D) in a specific range of ratios.

[0010] In other words, the present invention relates to the following inventions [1] to [5].

[0011] [1] An adhesive resin composition comprising polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D) in a total of 100% by mass, wherein the content of each component is 40-80% by mass for polyethylene resin (A), 0-25% by mass for wax (B), 15-40% by mass for polyolefin resin (C), and 1-15% by mass for layered inorganic filler (D), wherein the polyolefin resin (C) is a polypropylene resin or a polybutene resin, and the wax (B) is polyethylene wax or Fischer-Tropsch wax. [2] The adhesive resin composition according to [1], wherein the layered inorganic filler (D) is talc or mica. [3] The adhesive resin composition according to [1] or [2], wherein the melt mass flow rate at 190°C and a load of 2.16 kg is 5 to 23 g / 10 min. [4] A laminated sheet comprising a base sheet and a coating of the adhesive resin composition described in any of [1] to [3]. A lid material made of laminated sheets as described in [5] and [4]. [Effects of the Invention]

[0012] The adhesive resin composition of the present invention provides an adhesive resin composition that exhibits good moldability, ease of opening, and stringing properties regardless of the coating speed, as well as a sheet and lid material laminated with a film of the adhesive resin composition. [Modes for carrying out the invention]

[0013] The adhesive resin composition of the present invention is an adhesive resin composition in which, in a total of 100% by mass of polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D), the content of each component is 40-80% by mass of polyethylene resin (A), 0-25% by mass of wax (B), 15-40% by mass of polyolefin resin (C), and 1-15% by mass of layered inorganic filler (D), wherein wax (B) includes polyethylene wax or Fischer-Tropsch wax. In particular, the use of layered inorganic filler (D) is a characteristic feature. The inorganic filler plays the role of island phases and does not melt when heated, so its shape does not change with the molding speed. Furthermore, the layered shape of the inorganic filler has the effect of promoting cohesive failure, and the polyolefin resin (C) has the effect of mitigating deformation due to strain during molding, thereby suppressing the occurrence of stringing. In the adhesive resin composition of the present invention, the polyethylene resin (A) forms the sea phase, and the polyolefin resin (C) and layered inorganic filler (D) form the island phase. The polyolefin resin (C) is either a polypropylene resin or a polybutene resin. When the layered inorganic filler (D) is used alone without the polyolefin resin (C), if the amount of layered inorganic filler (D) is increased, holes appear in the adhesive resin composition during molding, preventing film formation. On the other hand, if the amount is decreased, sufficient island phases cannot be formed to cause cohesive failure, resulting in paper peeling. Therefore, it is impossible to find a balance. Based on the above, it is possible to provide an adhesive resin composition that exhibits good moldability, easy opening, and stringing properties regardless of the coating speed.

[0014] The adhesive resin composition of the present invention, a sheet on which a film of the adhesive resin composition is laminated, and a lid material manufactured from the sheet will be described in more detail below.

[0015] <Polyethylene resin (A)> The polyethylene resin (A) in the present invention may be either an ethylene homopolymer or a copolymer of ethylene and an olefin. Specifically, any homopolymer such as high-pressure low-density polyethylene, high-density polyethylene, or linear low-density polyethylene can be used, as long as mismatch or partial mismatch can be maintained. Alternatively, a copolymer obtained by polymerizing ethylene with at least one selected from the group consisting of propylene, butene, pentene, hexene, or long-chain olefins with 7 or more carbon atoms can be used in any ratio. Among these, high-pressure low-density polyethylene is preferred because it is easily broken and stringing can be suppressed. The content of polyethylene resin (A) is 40 to 80% by mass, more preferably 42 to 75%, and particularly preferably 45 to 70%, of the total mass of polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D). Within this range, stable molding is possible regardless of the molding conditions.

[0016] The polyethylene resin (A) has a melt mass flow rate of 0.1 to 100 g / 10 min at 190°C and a load of 2.16 kg, according to JIS K7210, more preferably 0.5 to 50 g / 10 min, and particularly preferably 1 to 30 g / 10 min. This range is preferable because it allows for stable molding regardless of the molding conditions.

[0017] <Wax (B)> The wax (B) in this invention includes polyethylene wax or Fischer-Tropsch wax. Other waxes may be used in combination as long as they contain polyethylene wax or Fischer-Tropsch wax. It is preferable to include polyethylene wax, which exhibits higher compatibility with polyethylene resin (A). In this specification, a polyethylene compound is defined as polyethylene resin (A) if its melt mass flow rate at 190°C and a load of 2.16 kg, as specified in JIS K7210, is 100 g / 10 min or less, and as wax (B) if its melt mass flow rate at 190°C and a load of 2.16 kg, as specified in JIS K7210, exceeds 100 g / 10 min.

[0018] The content rate of wax (B) is 0 to 20% by mass, more preferably 1 to 18% by mass, and particularly preferably 2 to 16% by mass in the total 100% by mass of the polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D). It is preferable that it is within the above range in terms of suppressing thread drawing. When wax (B) contains other waxes other than polyethylene wax and Fischer-Tropsch wax, its content rate is preferably less than 5% by mass in the total 100% by mass of the polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D).

[0019] The viscosity of wax (B) at 140°C is preferably 1 to 10,000 mPa·s, more preferably 3 to 8000 mPa·s, and particularly preferably 5 to 6000 mPa·s. It is preferable that it is within the above range in terms of enabling both T-die molding and thread drawing. The viscosity is a measured value using a B-type viscometer (measurement conditions: 140°C, rotor No2, 30 rpm, 30 seconds). Details are described in the column of the examples.

[0020] <Polyolefin resin (C)> The polyolefin resin (C) in the present invention is a polypropylene resin or a polybutene resin. The polypropylene resin may be a propylene homopolymer or a copolymer of propylene and an olefin. Also, the polybutene resin may be a polybutene homopolymer or a copolymer of butene and an olefin. Specifically, as long as it can maintain incompatibility or partial compatibility with the polyethylene resin (A), a propylene homopolymer, or a copolymer obtained by polymerizing at least one selected from the group consisting of ethylene, butene, pentene, hexene, or an olefin having a long carbon chain with 7 or more carbon atoms and propylene at an arbitrary ratio, a polybutene homopolymer, or a copolymer obtained by polymerizing at least one selected from the group consisting of ethylene, propylene, pentene, hexene, or an olefin having a long carbon chain with 7 or more carbon atoms and butene at an arbitrary ratio can be used. Among them, a propylene homopolymer, a propylene-ethylene copolymer, a polybutene homopolymer, and a butene-ethylene copolymer are preferable from the viewpoint of suppressing the occurrence of stringing. The polyolefin resin (C) is 15 to 40% by mass, more preferably 16 to 35% by mass, and particularly preferably 17 to 30% by mass in the total 100% by mass of the polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D). It is preferable to be within the above range in that it can suppress paper peeling and stringing.

[0021] The melt mass flow rate of the polypropylene resin at 230°C and a load of 2.16 kg according to JIS.K7210 is preferably 0.1 to 50 g / 10 min, more preferably 0.2 to 20 g / 10 min, and particularly preferably 0.3 to 10 g / 10 min. Also, the melt mass flow rate of the polybutene resin at 190°C and a load of 2.16 kg according to JIS.K7210 is preferably 0.1 to 50 g / 10 min, more preferably 0.2 to 20 g / 10 min, and particularly preferably 0.3 to 10 g / 10 min. It is preferable to be within the above range in that it can be stably molded regardless of the molding conditions.

[0022] <Layered inorganic filler (D)> The layered inorganic filler (D) in this invention is not particularly limited as long as it is a thin, plate-like crystal of nanometer size. Talc and mica are preferred because they provide a smooth peeling sensation through cohesive fracture.

[0023] The average particle size of the layered inorganic filler is not particularly limited as long as it can be broken down by aggregation, but it is preferably 1 to 30 μm, and more preferably 3 to 15 μm. Being within this range is preferable because it provides a good balance between stable moldability, ease of opening, and suppression of stringing.

[0024] The content of the layered inorganic filler (D) is 1 to 15% by mass, more preferably 2 to 13% by mass, and particularly preferably 3 to 12% by mass, of the total mass of the polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D). This range is preferable because it suppresses stringing regardless of molding conditions.

[0025] ≪Adhesive resin composition≫ The adhesive resin composition in the present invention contains polyethylene resin (A) (hereinafter abbreviated as (A)), wax (B) (hereinafter abbreviated as (B)), polyolefin resin (C) (hereinafter abbreviated as (C)), and layered inorganic filler (D) (hereinafter abbreviated as (D)) in a composition of (A):(B):(C):(D) = 40~80:0~20:15~40:1~15 (mass%), preferably (A):(B):(C):(D) = 42~75:1~18:16~35:2~13 (mass%), and more preferably (A):(B):(C):(D) = 45~70:2~16:17~30:3~12 (mass%). However, the total of (A), (B), (C), and (D) is 100% by mass. Furthermore, the sum of (C) and (D) is preferably 15 to 49% by weight, more preferably 20 to 45% by mass, and particularly preferably 25 to 40% by mass, in order to form sea islands for cohesive breakdown and to improve ease of opening.

[0026] The adhesive resin composition of the present invention may further contain additives to prevent thermal degradation, thermal decomposition, blocking, etc., and to ensure suitability for processing such as film processing and extrusion lamination, to the extent that it does not impair the purpose of the present invention. Examples of additives include hindered phenol-based and phosphorus-based antioxidants, other blocking inhibitors, antistatic agents, pigments, etc.

[0027] These additives may be added during the compounding of polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D), or they may be kneaded into one of the polyethylene resin (A), wax (B), polyolefin resin (C), or layered inorganic filler (D) beforehand, and then compounded by kneading the polyethylene resin (A), wax (B), polyolefin resin (C), or layered inorganic filler (D) with other components.

[0028] The amount of additive is less than 15 parts by mass, preferably less than 10 parts by mass, and more preferably less than 5 parts by mass, based on 100 parts by mass of the total of polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D). Within this range is preferable in that moldability and stringiness are not impaired.

[0029] The polyethylene resin (A), wax (B), polyolefin resin (C), layered inorganic filler (D), and additives used as needed are compounded, for example, by putting each component into a mixing device such as a Henschel mixer or tumbler mixer, mixing for 5 to 20 minutes, then placing the mixture in an extruder, heating and kneading it, and then extruding it. The extruded material is usually in the form of pellets and used in subsequent processes. A twin-screw extruder is preferred as the extruder, but it is not limited to this. The extrusion is usually carried out at 140 to 200°C.

[0030] The adhesive resin composition of the present invention preferably has a melt mass flow rate of 5 to 23 g / 10 min, more preferably 6 to 20 g / 10 min, and particularly preferably 7 to 17 g / 10 min, measured under conditions of 190°C and a load of 2.16 kg. This range is preferable because it allows for the use of both the T-die method and the inflation method.

[0031] Laminated Sheet The laminated sheet of the present invention comprises a base sheet and a coating of the adhesive resin composition of the present invention. The coating of the adhesive resin composition may be directly laminated onto the base sheet, or another layer may be arranged between the base sheet and the coating of the adhesive resin composition. Examples of base sheets that can be used include paper, aluminum, polyester, polyethylene, polypropylene, polystyrene, aluminum-deposited polyester, aluminum-deposited polypropylene, silica-deposited polyester, etc. The base sheet does not need to be a single layer, but may be a laminate of two or more layers. In this application, it is preferable to use, for example, a laminate of PET with a thickness of 5 to 20 μm and polyethylene with a thickness of 5 to 30 μm as the base sheet. As a method for laminating the adhesive resin composition of the present invention onto a substrate sheet, for example, a method is used in which the pelletized resin composition as described above is formed into a single-layer film by an inflation method or a casting method, and this film is laminated to the substrate sheet with an adhesive layer if necessary. Alternatively, the kneaded composition may be directly coated onto the substrate sheet, or other methods may be used.

[0032] To improve the adhesion of the laminated surface, the substrate sheet surface may be treated with flame treatment, ozone treatment, corona discharge treatment, or an anchor coating agent. For substrates that have been pre-laminated with polyethylene resin, direct extrusion lamination is also possible. Alternatively, a multilayer film can be formed by co-extrusion with polyethylene or polypropylene, and then laminated with a stretched or unstretched film such as a polyester film, polyamide film, or polypropylene film, which will serve as the substrate, by dry lamination or sand lamination to obtain a laminated sheet. In this case as well, to improve the adhesion of the laminated surface, if necessary, the substrate sheet surface may be treated with flame treatment, ozone treatment, corona discharge treatment, or an anchor coating agent. Furthermore, the thickness of the adhesive resin composition layer of the present invention is 5 μm or more, and preferably 10 μm or more. In this invention, the term "sheet" is used to encompass long and cut short films and sheets, and the base sheet also includes single-layer and multi-layer laminates. Furthermore, laminated sheets made of the adhesive resin composition of this invention can be used as lids as described later, and can also be suitably used in bag products (bonding adhesive resin composition surfaces to each other) in which the adhesive resin composition surface is sealed to the inner surface.

[0033] ≪Lid material≫ The lid material of the present invention is formed from the laminated sheet of the present invention, and the laminated sheet is cut to match the opening shape of the container body to be sealed. The lid material seals the opening of the container body. The adhesive resin composition of the present invention, which is disposed on one side of the lid material, is brought into contact with the adhesive surface (also called the flange) of the opening of the sealed container and heated to bond them together. The bonding temperature is preferably 130 to 170°C. As the base sheet, it is preferable to use a laminate of PET with a thickness of 5 to 20 μm and polyethylene with a thickness of 5 to 30 μm. Furthermore, the lid material of the present invention is preferably made by laminating a film of the adhesive resin composition of the present invention with a thickness of 5 to 40 μm onto the polyethylene surface of the laminate.

[0034] <Container body> As the container body to which the lid material of the present invention is adhered, a container body made of polyethylene resin or a container body whose inner surface is covered with polyethylene resin is preferred. Because the container is made of polyethylene resin, it fuses when heat-bonded to the adhesive resin composition, which makes it more susceptible to cohesive failure. [Examples]

[0035] The present invention will be described below based on examples, but the present invention is not limited thereto. In the examples, "parts" and "%" represent "parts by mass" and "mass%", respectively.

[0036] The viscosity of polyethylene resin (A), polyolefin resin (C), melt mass flow rate (hereinafter referred to as MFR) of adhesive resin composition, and wax (B) was measured by the following method.

[0037] (MFR) Samples were filled into a 9.55 mm inner diameter, 162 mm long cylinder of a Melt Indexer L244 (manufactured by Takara Kogyo Co., Ltd.). Polyethylene and polybutene were melted at 190°C, and polypropylene at 230°C. A 2.16 kg plunger with a diameter of 9.48 mm was used to apply a uniform load, and the amount of resin extruded per unit time (g / 10 min) through a 2.1 mm diameter orifice located in the center of the cylinder was used to determine the amount of resin extruded.

[0038] (viscosity) The measurement was taken using a VISCOMETER TVB-10 (a Type B viscometer manufactured by TOKI SANGYO) at a temperature of 140°C, with rotor No. 2, 30 rpm, and a time of 30 seconds.

[0039] <Method for producing adhesive resin composition> [Example 1] (Manufacturing of adhesive resin composition (S-1)) Fifty parts of polyethylene resin (A) A1 (LOTTE, XL610H, low-density polyethylene), fifty parts of wax (B) B2 (LION CHEMTECH, L-C121N, low-density polyethylene), twenty-five parts of polyolefin resin (C) C1 (LOTTE, SB-520, propylene-ethylene copolymer), ten parts of layered inorganic filler (D) D2 (KOCH, KCNAP-400, talc), and 0.1 parts of antioxidant (IRGANOX1010) were pre-blended in a Henschel mixer for five minutes. The pre-blended material was put into a hopper and supplied to the extruder using a screw feeder to obtain adhesive resin composition (S-1). The MFR was 15 g / 10 min.

[0040] [Examples 2-13 and Comparative Examples 1-8] (Manufacturing of adhesive resin compositions (S-2) to (S-21)) Adhesive resin compositions (S-2) to (S-21) were prepared in the same manner as in Example 1, except that the raw materials and proportions shown in Tables 1 and 2 were used, and the MFR was measured.

[0041] Extruder Conditions Extruder: IKG Corporation co-rotating twin-screw extruder PMT32-40.5 Barrel temperature: 180℃ (feed port 160℃) Screw rotation speed: 200 rpm Feeding rate: 10kg / hr

[0042] <Evaluation of adhesive resin compositions> Laminated sheets (lid material) were prepared from the obtained adhesive resin compositions (S-1) to (S-21) according to the following procedure, and the moldability, paper peeling, and stringing properties of these laminated sheets were evaluated based on the following methods and criteria. The results are shown in Tables 1 and 2.

[0043] (Method for manufacturing laminated sheets (lid material)) The obtained adhesive resin composition was laminated to a thickness of 20 μm on the PE surface of a PET 12 μm / PE 25 μm substrate using a T-die extrusion laminator to create a laminated sheet. The processing conditions are shown below. T-die extrusion laminator: Musashino Kikai EXT laminator T-die direct resin temperature: 250°C to 280°C (adjusted by MFR of adhesive resin composition, etc.) Molding speed (3 levels): 30m / min, 80m / min, 150m / min

[0044] <Moldability> The moldability of the T-die extrusion laminator at three molding speeds (30 m / min, 80 m / min, and 150 m / min) was evaluated according to the following criteria, starting from the lowest speed. ○: Can be molded without any problems... Excellent △: Requires adjustment but can be molded... Usable ×: The adhesive resin composition is punctured, cut, etc., making molding impossible: Not usable.

[0045] <Easy to open> The obtained laminated sheet (lid material) was cut to a size of 90 mm x 90 mm, and the adhesive resin composition side was heat-bonded to a 71Φ paper / PE container at a gauge pressure of 0.2 MPa, 150°C, and 1 second, and then sealed. It was left in a constant temperature and humidity chamber at 23°C and 65% humidity for 24 hours, and the ease of opening was evaluated in the same constant temperature and humidity chamber under the conditions of 90° angle peeling and a tensile speed of 200 mm / min according to the following criteria. ○: It peeled off smoothly and easily... Excellent △: High peeling resistance, requires force... Usable ×: Lid is broken or container is deformed: Unusable -: Evaluation impossible because lid material could not be obtained due to inability to mold with a T-die.

[0046] <Stringy properties> During the evaluation of the ease of peeling described above, the paper / PE container flange was observed, and the presence or absence of stringing was evaluated according to the following criteria. ○: No string pulling was observed... Excellent △: Slight stringing was observed... Usable ×: Numerous instances of string pulling were observed... Unusable -: The lid material could not be obtained because it could not be molded with the T-die, or because it could not be peeled off and stringing could not be confirmed, therefore evaluation is not possible.

[0047] [Table 1]

[0048] [Table 2]

[0049] The abbreviations for the raw materials used in the examples and comparative examples are shown below. A1: XL610H (Lotte, low-density polyethylene, MFR 8g / 10 min (190℃)) A2: XJ700H (Lotte, low-density polyethylene, MFR 22g / 10 min (190℃))

[0050] B1: Sasol H1 (Sasol brand, paraffin wax, viscosity 8 mPa·s (140℃)) B2: L-C121N (manufactured by Lion Chemtech, low-density polyethylene, viscosity 1100 mPa·s (140℃), MFR over 100 g / 10 min (190℃)) B3:720P (Manufactured by Mitsui Chemicals, low-density polyethylene, viscosity 6000 mPa·s (140℃), MFR over 100g / 10min (190℃)) B4:1120H (manufactured by Mitsui Chemicals, 20% by mass styrene monomer content, grafted ethylene-propylene copolymer, viscosity 40 mPa·s (140℃), MFR over 100 g / 10 min (190℃))

[0051] C1: SB-520 (manufactured by Lotte, propylene-ethylene copolymer, MFR 2g / 10 min (230℃)) C2: BL-3110 (manufactured by Mitsui Chemicals, butene-ethylene copolymer, MFR 1g / 10 min (190℃))

[0052] D1: SG-95 (manufactured by Nippon Talc Co., Ltd., talc, layered, average particle size 2 μm) D2: KCNAP-400 (manufactured by KOCH, talc, layered, average particle size 11 μm) D3: CS-10 (Manufactured by Seishin Corporation, mica, layered, average particle size 10 μm) D4: CS-20 (Manufactured by Seishin Corporation, mica, layered, average particle size 20 μm)

[0053] As shown in Tables 1 and 2, compared to Comparative Examples 1 to 8, Examples 1 to 13 of the present invention demonstrated that they achieved excellent moldability, ease of opening, and stringing properties regardless of the coating speed. Therefore, the present invention is demonstrated to be optimal as an adhesive resin composition that does not cause paper peeling or stringing regardless of the molding conditions.

Claims

1. The content of each component in a total of 100% by mass of polyethylene resin (A), wax (B), polyolefin resin (C), and layered inorganic filler (D) is 40-80% by mass for polyethylene resin (A), 0-25% by mass for wax (B), 15-40% by mass for polyolefin resin (C), and 1-15% by mass for layered inorganic filler (D), Polyethylene resin (A) is low-density polyethylene. Polyolefin resin (C) is a polypropylene resin or a polybutene resin. Wax (B) comprises polyethylene wax or Fischer-Tropsch wax, wherein the polyethylene wax is low-density polyethylene. Adhesive resin composition.

2. The adhesive resin composition according to claim 1, wherein the layered inorganic filler (D) is talc or mica.

3. The adhesive resin composition according to claim 1, wherein the melt mass flow rate at 190°C and a load of 2.16 kg is 5 to 23 g / 10 min.

4. A laminated sheet comprising a base sheet and a coating of the adhesive resin composition described in any one of claims 1 to 3.

5. A lid material made of laminated sheets as described in claim 4.

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