JP5386804B2 - Easy-release adhesive for polyolefin and its structure - Google Patents

Description

  The present invention relates to an adhesive having an easy-release property to components such as containers and sheets having polypropylene, polyethylene or ethylene-vinyl acetate copolymer as an adherend surface, and a structure thereof. More specifically, it is characterized by comprising ethylene-vinyl acetate copolymer resin (A) 40 to 77 wt%, crystalline polypropylene resin (B) 10 to 40 wt%, and low molecular weight polyethylene wax (C) 3 to 30 wt%. The present invention relates to an easily peelable adhesive for polyolefin and a structure thereof.

  In recent years, due to the problem of industrial waste, food containers are being changed from polystyrene or polyvinyl chloride to polyethylene or polypropylene that does not generate harmful gases during combustion. In particular, containers using polypropylene or polyethylene or containers obtained by laminating polyethylene on paper have been used. For example, polypropylene containers that are injection-molded for pudding or jelly, or vacuum or pressure-molded after sheet molding, extruded polyethylene and laminated on paper, cup-shaped containers for yogurt, mayonnaise, ketchup, etc. And a polyethylene container such as a drip bottle.

The aforementioned container requires an adhesive that can be handled safely without being broken during transportation, and that can be easily opened by women and children when opened. As an adhesive for that purpose, for example, 1) a composition in which a resin (eg, polyethylene, ethylene-vinyl acetate copolymer, etc.) that can adhere to polyethylene is mixed with a resin (eg, polypropylene) that is basically difficult to adhere to polyethylene. 2) A so-called hot melt composition obtained by mixing an ethylene-vinyl acetate copolymer with a tackifier, a low molecular weight wax, and the like. 3) A high molecular weight type hot melt composition in which the above hot melt type can be extruded. ) A composition in which low molecular weight polyethylene is blended with high molecular weight polybutene (see, for example, Patent Document 1), 5) Polyethylene easy-peeling adhesive (for example, patent) comprising polyethylene resin, crystalline polybutene resin, and low molecular weight wax Reference 2). The inventors have also filed for 6) an easily peelable resin composition for polyethylene containers and its structure. (See Patent Document 3)
JP-A-1-315443 JP 2003-129018 A JP 2007-112955 A

  However, the above composition does not adhere to polypropylene containers, and has various problems with polyethylene containers, and is not satisfactory as an easily peelable adhesive. That is, the composition of 1) is inferior in processability because it is mixed with resins that are hardly compatible with each other, and is not flexible enough to fill a step required for sealing a paper cup container, thereby preventing liquid leakage. Not suitable for. In addition, when the adhesive strength is increased, a so-called stringing phenomenon in which the adhesive breaks in a streak shape occurs, and the appearance after peeling becomes worse. The composition of 2) has sufficient fluidity and sealing strength to fill the steps of the paper cup container, but requires a special coater during processing, and because it has poor heat resistance, it adheres inside the container during heat sealing. There is a risk of contamination. Although the composition of 3) is excellent in heat resistance, it has high adhesive strength with polyethylene and is not easily peelable. Since the adhesive strength becomes lower as the heat seal temperature is lower, a method of sealing by limiting the use temperature is conceivable. However, since the temperature dependency is high, the variation in the adhesive strength is large, and there is a problem in quality as a product. In the composition 4), when the melt mass flow rate (hereinafter referred to as MFR) measured in accordance with JIS K6922-1 of low density polyethylene is 20 g / 10 min or less, polyethylene which is one of the objects of the present invention is laminated. The peel strength is too high for the paper container or sheet, and so-called paper peeling that breaks the paper occurs. If the MFR of the low density polyethylene is set to 20 to 70 g / 10 minutes in order to maintain the peelability, the melt tension is low and the extrusion lamination processability is poor. The adhesive of 5) can be used without problems when the thickness of the polyethylene layer laminated on the inner surface of the paper container is 40 μm or more, but the polyethylene layer laminated on the inner surface of the paper container is, for example, about 30 μm. When it is thinned, the film strength of the polyethylene layer is weakened and easily broken, so that a paper peeling phenomenon is likely to occur. Moreover, since polybutene is generally expensive, there is a drawback that the composition is also expensive. Although the present inventor proposed 6) is effective for polyethylene containers, it is not adhesive to polypropylene containers, and the sealing temperature for polyethylene containers is 120 ° C. or less. Inferior in low-temperature adhesion.

  Therefore, in the present invention, a container or sheet made of polypropylene, polyethylene, or an ethylene-vinyl acetate copolymer (hereinafter sometimes referred to as EVA), a paper container laminated with polyethylene, polypropylene, polyethylene, or EVA is used as the adherend surface. Extrusion lamination is possible for components such as multi-layer containers or multi-layer sheets, and adhesives that are easily peelable and have sufficient heat seal strength and low temperature seal properties to protect the contents, and The object is to provide the structure.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that easy-peelable adhesion for polyolefins containing a specific amount of ethylene-vinyl acetate copolymer resin, crystalline polypropylene resin and low molecular weight polyethylene wax. The present inventors have found that the agent is excellent in processability and is excellent as an easily peelable adhesive with respect to an adherend surface on which at least one surface is polypropylene, polyethylene or EVA, and has led to the present invention.

  That is, the present invention relates to ethylene-vinyl acetate copolymer resin (A) 40-77 wt%, crystalline polypropylene resin (B) whose vinyl acetate content measured in accordance with JIS K6924-1 is in the range of 3-15 wt%. A polyethylene wax having a number average molecular weight of 1,000 to 10,000 by GPC method, or ethylene-acetic acid having a viscosity of 50 to 1,000 mPa · s measured at 180 ° C. using a Brookfield viscometer The present invention relates to an easily peelable adhesive for polyolefins and a structure thereof comprising 3 to 30 wt% of a low molecular weight polyethylene wax (C) selected from any of vinyl copolymers.

  The present invention is described in detail below.

  The ethylene-vinyl acetate copolymer resin (A) used in the present invention is an ethylene-vinyl acetate copolymer resin obtained by a known production method and has a vinyl acetate content of 3 measured according to JIS K6924-1. It is in the range of ˜15 wt%. If the vinyl acetate content is less than 3%, there is no adhesion to polypropylene and low temperature sealability cannot be obtained. Although the low-temperature adhesiveness is good when the vinyl acetate content exceeds 15%, the adhesiveness to polyethylene becomes too high and the easy peeling property is lost, and the lid material has poor heat resistance for polypropylene containers. turn into. The MFR of the ethylene-vinyl acetate copolymer resin (A) measured according to JIS K6924-1 is not particularly limited, but is preferably 10 to 50 g / 10 min from the viewpoint of maintaining the stability of extrusion processing.

  As a specific EVA resin (A), for example, EVA (trade name: Ultrasen) manufactured by Tosoh Corporation can be used.

  The crystalline polypropylene resin (B) used in the present invention is not particularly limited as long as it is a crystalline polymer composed of a propylene homopolymer or a copolymer of propylene and ethylene. A copolymer is preferred. The MFR of the crystalline polypropylene resin (B) measured according to JIS K7210 is not particularly limited, but is preferably 1 to 30 g / 10 minutes from the viewpoint of preventing the stringing phenomenon at the time of peeling. In particular, it is preferably 0.5 to 10 g / 10 minutes.

  As a specific crystalline polypropylene resin (B), for example, a crystalline polypropylene resin (trade name: Novatec PP) manufactured by Nippon Polypro Co., Ltd. can be used.

  The low molecular weight polyethylene wax (C) used in the present invention is a low molecular weight polyethylene wax or a low molecular weight EVA wax. When (C) is a low molecular weight polyethylene wax, it is a polyethylene wax having a number average molecular weight of 1,000 to 10,000 according to the GPC method. The low molecular weight polyethylene wax has a polymerization type obtained by polymerization of ethylene, a molecular weight of Either of the decomposition types obtained by thermally decomposing high polyethylene can be used. When (C) is a low molecular weight EVA wax, the viscosity measured at 180 ° C. using a Brookfield viscometer is 50 to 1,000 mPa · s. If the viscosity measured at 180 ° C. using a Brookfield viscometer is less than 50 mPa · s, the viscosity is too low and the molding stability of the blend is inferior. Is likely to occur. In order to improve the adhesion to polypropylene and the low temperature adhesion, the low molecular weight polyethylene wax is preferably a low molecular weight EVA wax.

  As a specific low molecular weight polyethylene wax (C), for example, a low molecular weight polyethylene wax (trade name: Sunwax) manufactured by Sanyo Chemical Industries, Ltd. can be used. In addition, as a specific low molecular weight EVA wax, EVA wax (trade name: Special Ultrasen) manufactured by Tosoh Corporation can be used.

  Since the easy-peelable adhesive for polyethylene of the present invention is an adhesive excellent in extrusion lamination processability, JIS K6924 is a blend of ethylene-vinyl acetate copolymer resin (A) and low molecular weight polyethylene wax (C). MFR (A + C) measured according to -1 is preferably 40 to 400 g / 10 min from the viewpoint of controlling the dispersibility of crystalline polypropylene and preventing the stringing phenomenon, and in particular 50 to 300 g / 10 min. It is preferable that Moreover, MFR (A + B + C) of all the compounds (ethylene-vinyl acetate copolymer resin (A) + crystalline polypropylene resin (B) + low molecular weight polyethylene wax (C)) measured according to JIS K6922-1 ) Is preferably 10 to 60 g / 10 min from the viewpoint of maintaining the stability of the extrusion process.

  The composition of the easily peelable adhesive for polyethylene of the present invention is as follows: ethylene-vinyl acetate copolymer resin (A) 40 to 77 wt%, crystalline polypropylene resin (B) 10 to 40 wt%, low molecular weight polyethylene wax (C ) Is 3 to 30 wt%. Among these blending amounts, the blending amount of the low molecular weight polyethylene wax (C) is particularly preferably 10 to 20 wt%.

  If the blending amount of the ethylene-vinyl acetate copolymer resin (A) is less than 40 wt%, the processability is inferior, and a stringing phenomenon (adhesive stretches and peels off) occurs during peeling. When the blending amount of the ethylene-vinyl acetate copolymer resin (A) exceeds 77 wt%, the adhesive strength with polyethylene as the adherend becomes too high. Further, when the blending amount of the crystalline polypropylene resin (B) is less than 10 wt%, the polyethylene component is increased, and the adhesive strength with polyethylene as the adherend is increased, that is, as an inner paste of the paper container as the adherend. The adhesive strength with the polyethylene film used increases, and the paper fiber is peeled off (material destruction) while breaking the fiber. Moreover, when the compounding quantity of crystalline polypropylene resin (B) exceeds 40 wt%, although the adhesive strength will fall, the extrusion stability of a compound will become inferior. Furthermore, when the blending amount of the low molecular weight polyethylene wax (C) exceeds 30 wt%, the melt tension of the entire blend is lowered, and the extrusion laminating processability is lowered. Moreover, when the compounding quantity of low molecular weight polyethylene-type wax (C) is less than 3 wt%, the dispersibility of ethylene-vinyl acetate copolymer resin (A) and crystalline polypropylene-type resin (B) falls, and peeling Sometimes the stringing phenomenon tends to occur.

  In the easily peelable adhesive for polyolefins of the present invention, additives that are blended in ordinary polyolefin resins, that is, additives such as antioxidants, lubricants, antistatic agents, antifogging agents, antiblocking agents, etc., are added to the present invention. The required amount can be added as long as the performance of the easy-peelable adhesive for polyethylene is not impaired.

  The preparation of the easily peelable adhesive for polyolefin of the present invention is not particularly limited, and for example, ethylene-vinyl acetate copolymer resin (A), crystalline polypropylene resin (B), low molecular weight polyethylene wax (C) and If necessary, a predetermined amount of a lubricant, an antioxidant, an antistatic agent, etc. are dry blended, extruded into a strand having a diameter of about 2 to 3 mm while being melt-kneaded with a single screw or twin screw extruder, cooled and solidified, By cutting with a rotary blade, an easily peelable adhesive for polyolefin can be obtained.

  The polyolefin easy-peelable adhesive of the present invention can be laminated to the adherend, has heat-seal strength and low-temperature sealability sufficient to protect the contents, and has easy-release properties. It becomes an inexpensive adhesive.

  There is no restriction | limiting in particular as a structure of the easily peelable adhesive agent for polyolefins of this invention, For example, the structure which has the easily peelable adhesive agent for polyolefins on at least one side is mentioned. And as an adherend of the adhesive of the present invention for easy peeling for polyethylene, there is no particular limitation as long as it is polypropylene, polyethylene or EVA, for example, polyethylene such as low density polyethylene, linear low density polyethylene, high density polyethylene, Examples thereof include polypropylene and an ethylene-unsaturated carboxylic ester copolymer represented by EVA. Among them, polyethylene, polypropylene, and EVA are preferably adherends.

  The method for producing the polyolefin easy-peelable adhesive structure of the present invention is not particularly limited. For example, the pelletized easy-peelable polyolefin adhesive of the present invention is used, and is usually used for molding a polyethylene resin. After forming into a single-layer film by the method, that is, cast molding or inflation molding, it is coextruded with an adherend such as low density polyethylene, linear low density polyethylene, high density polyethylene, polypropylene, ethylene-unsaturated carboxylic ester copolymer, etc. By doing so, a method of manufacturing a structure can be used.

  The structure of the easily peelable adhesive for polyethylene of the present invention has at least one easy peelable adhesive for polyethylene, and further provides a base material for imparting printability, glossiness, rigidity and the like required as a packaging material. You may have. And there is no restriction | limiting in particular as this base material, For example, plastic films, such as a polyester film, a polyamide film, a polypropylene film, paper, aluminum foil, etc. are mentioned. In addition, when bonding a base material, it is preferable to bond through adhesives, such as a polyester-type adhesive agent.

  As a method for laminating the substrates, for example, lamination with a stretched or unstretched film such as a polyester film, a polyamide film, or a polypropylene film can be performed by dry lamination, sandwich lamination, or extrusion lamination. More specifically, for example, a 15 μm thick polyamide film stretched biaxially and a structure film of the present invention cast in advance to a thickness of 30 μm are made of a polyester-based adhesive (trade name: Seika Bond, manufactured by Dainichi Seika Kogyo Co., Ltd.). E263 etc.) Dry lamination method: Isocyanate-based anchor coating agent (Nippon Soda Co., Ltd., trade name: Titabond T120, etc.) on a film obtained by laminating a 12 μm thick polyester film and a 12 μm thick polyester film deposited with aluminum. Examples include a method of sandwiching the coated surface and the 30 μm structure film of the present invention by extruding low density polyethylene (trade name: Petrocene 213 manufactured by Tosoh Corporation).

  When extrusion lamination is performed, an anchor coat agent (hereinafter referred to as AC agent) is applied in advance to a plastic film such as polyester film or polyamide film, or a substrate such as paper or aluminum foil, or ozone treatment is performed during processing. Therefore, it is preferable to laminate with various plastic films, aluminum foils and the like. By coextrusion lamination with a resin having good adhesion to the aluminum foil (for example, a resin having a peel strength of 2 N / 15 mm or more when extrusion lamination to an aluminum foil such as a copolymer of ethylene and acrylic acid) is performed. It is also possible to laminate on an aluminum foil without using an agent.

  Moreover, it is also possible to carry out extrusion lamination directly with respect to the base material which has been laminated with a polyethylene resin in advance. As used herein, the polyethylene resin can be bonded to the polyethylene easy-peelable adhesive of the present invention, and can be used as a lid material and has an adhesive strength that does not delaminate when peeled from a container. There is no particular limitation, for example, ethylene-unsaturated carboxylic acid such as low-density polyethylene, linear low-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, etc. And a copolymer. As a method of directly extruding and laminating a specific polyethylene resin to a previously laminated substrate, for example, an isocyanate anchor coating agent (manufactured by Nippon Soda Co., Ltd.) is added to a biaxially stretched 12 μm thick polyester film. : Lamination of low density polyethylene (trade name: Petrocene 213 manufactured by Tosoh Corporation) in advance using Titabond T120, etc., and 25 μm extrusion lamination of the easily peelable adhesive for polyethylene of the present invention thereon. Is mentioned.

  The structure of the easily peelable adhesive for polyethylene of the present invention can be used, for example, as a lid, more preferably a container lid made of polypropylene, polyethylene, or EVA. Examples of the object to which the structure is bonded include, for example, an injection-molded polypropylene container and a lamination container obtained by ironing a composition in which low-density polyethylene is laminated on paperboard. Examples thereof include paper cups for yogurt and cup noodles, detergent containers that are polyethylene single-layer blow containers, and infusion bags such as ketchup and mayonnaise containers that are multilayer blow containers.

  In addition, the adherend to which the polyolefin easy-peelable adhesive of the present invention is bonded may be polypropylene, polyethylene or EVA at least on the adherend surface, and vinylidene chloride, ethylene-vinyl alcohol copolymer or aluminum is used during the construction. A container or a sheet in which a packaging material having a barrier property such as the above is used may be used.

  As described above, the easily peelable adhesive for polyolefins of the present invention can be extruded, and can be used as an easily peelable adhesive with polypropylene, polyethylene and EVA while being a polyolefin resin. It is useful as an adhesive for containers, sheets and the like that are polyethylene or EVA.

  The structure of the easy-peelable adhesive for polyolefins of the present invention adheres to the polypropylene or polyethylene to be bonded at a low temperature, and the peeling form is cohesive peeling, so that it has stable adhesive performance that is not affected by the sealing temperature. Can do.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples. Unless otherwise specified, commercially available reagents were used. The measurement methods used in the examples are shown below.

~ Melt Mass Flow Rate (MFR) ~
MFR (A + C) of a blend of ethylene-vinyl acetate copolymer resin (A) and low molecular weight polyethylene wax (C) and all blends (ethylene-vinyl acetate copolymer resin (A) + crystalline polypropylene resin (B ) + Low molecular weight polyethylene wax (C)) MFR (A + B + C) was measured according to JIS K6922-1.

  The MFR of the crystalline polypropylene resin (B) was measured according to JIS K7210.

-Measurement of number average molecular weight of low molecular weight polyethylene wax-
Measured by GPC.

Equipment: HLC-8121GPC / HT manufactured by Tosoh Corporation
Column: TSK-GEL GMHHR-H (20) HT × 3 Concentration: 1.0 mg / ml
Column temperature: 140 ° C
-Viscosity measurement of low molecular weight ethylene-vinyl acetate copolymer wax-
Measured using a Brookfield viscometer.

Device name: BROOKFIELD DIGITAL VISCOMETER
Equipment manufacturer: Brookfield Engineering Laboratories, Inc. Format: RVTDV-II
Measurement temperature: 180 ° C
Example 1
The ethylene-vinyl acetate copolymer resin (A) has a vinyl acetate content of 7% and an MFR of 25 g / 10 min. An ethylene-vinyl acetate copolymer resin (trade name: Ultrasen UE526, manufactured by Tosoh Corporation) 45 wt%, As crystalline polypropylene resin (B), crystalline polypropylene (manufactured by Nippon Polypro Co., Ltd., trade name: Novatec PPFW4BT) 35 wt%, low molecular weight ethylene-vinyl acetate copolymer wax (C) as crystalline polypropylene resin (B) 20 wt% of a resin having a viscosity of 240 mPa · s measured at 180 ° C. using a Brookfield viscometer (trade name: Special Ultrasen 7A55A manufactured by Tosoh Corporation) was blended. Furthermore, erucic acid amide as a lubricant with respect to a total of 100 parts by weight of the ethylene-vinyl acetate copolymer resin (A), the crystalline polypropylene resin (B), and the low molecular weight ethylene-vinyl acetate copolymer wax (C). 0.1 parts by weight (trade name: Neutron S manufactured by Nippon Seika Kogyo Co., Ltd.), phenolic antioxidant (Ciba Specialty Chemicals Co., Ltd., product name: Irganox 1010, below) After adding 0.05 parts by weight and dry blending, it is melt kneaded at a resin temperature of 180 ° C. with a 50 mm twin screw extruder, extruded into a strand shape with a diameter of 2 mm, cooled and solidified, and then rotated. Cut with a blade to obtain a pellet-like easily peelable adhesive for polyolefin. MFR (A + C) by blending ethylene-vinyl acetate copolymer resin (A) and low molecular weight polyethylene wax (C) in this blend was melt-kneaded and solidified so as to have the same ratio as this blend. A product was prepared separately and the MFR was measured and found to be 200 g / 10 min. Similarly, the MFR (A + B + C) of all formulations synthesized separately was 49 g / 10 min.

  Biaxially stretched polyester film (manufactured by Toyobo Co., Ltd., trade name: Toyobo Ester Film, hereinafter PET) (12 μm) and isocyanate anchor coating agent (manufactured by Nippon Soda Co., Ltd., trade name: Titabond T120) Low density polyethylene (trade name: Petrocene 213 manufactured by Tosoh Corporation) was extruded and laminated at a resin temperature of 310 ° C. at a resin temperature of 310 ° C. using a laminator, and further an ethylene-vinyl acetate copolymer (vinyl acetate content 15%, melt A flow rate of 15 g / 10 min) was extruded to 20 μm to obtain a three-layer film (PET / PE / EVA).

  On the EVA surface of this three-layer film, a pellet-like easy-release polyolefin adhesive was subjected to extrusion lamination at a resin temperature of 230 ° C. to a thickness of 25 μm to obtain a structure. This structure is used as a cover for the opening of a paper cup container (flange part outer diameter 100 mm, hereinafter referred to as PE paper cup) in which low-density polyethylene with a thickness of 40 μm is laminated on the inner surface so that the adhesive surface of the structure contacts And heat-adhered with a heat sealer (Sunny Pack Co., Ltd.). The heat sealing conditions were a temperature of 160 ° C., a pressure of 30 kg / cup, and a time of 0.8 seconds. After cooling at room temperature, the structure of the present invention was peeled from the paper cup container at an angle of 90 degrees, and the peel strength was measured using a push-pull gauge manufactured by Imada Corporation. At the same time, the presence or absence of the phenomenon of stringing at the time of peeling (adhesive stretches and peels off) and the destruction of material (the polyethylene of the paper cup peels from the paper) were confirmed. Using the body part of the paper cup described above, the peel strength from 100 ° C. to 180 ° C. is measured. As a comparison of peel strength, a peel strength of 160 degrees was used. The evaluation of the low temperature heat sealability was determined by the peel strength at 110 ° C. The heat sealing conditions were a pressure of 0.2 MPa and a time of 0.8 seconds. Furthermore, the adhesiveness with the polypropylene container was also cup-sealed in the same manner as the peel strength evaluation with the PE paper cup, and the peel strength was measured. The heat sealing conditions were a temperature of 180 ° C., a pressure of 30 kg / cup, and a time of 1.0 second. The processing stability during extrusion lamination processing was also evaluated. In addition, the processing stability was determined to be poor when the melted film during the extrusion lamination process meanders or a uniform film due to poor compatibility cannot be obtained, and the others are good.

  These results are shown in Table 1.

Example 2
The ethylene-vinyl acetate copolymer resin (A) used in Example 1 is an ethylene-vinyl acetate copolymer resin (manufactured by Tosoh Corporation) with a vinyl acetate content of 10% and an MFR of 9 g / 10 min. : Ultra-peelable adhesive and structure for polyolefin were obtained in the same manner as in Example 1 except that Ultrasen UE541 was used, and evaluated in the same manner as in Example 1. The results are shown in Table 1. The MFR (A + C) was 110 g / 10 minutes, and the MFR (A + B + C) was 30 g / 10 minutes.

Example 3
The ethylene-vinyl acetate copolymer resin (A) described in Example 1 is 50 wt%, the crystalline polypropylene (B) is 35 wt%, and GPC is used instead of the low molecular weight ethylene-vinyl acetate copolymer wax (C). Easy-peelable adhesive for polyolefins in the same manner as in Example 1 except that 15 wt% of a low molecular weight wax (trade name: Sunwax 151-P, manufactured by Sanyo Chemical Industries, Ltd.) having a number average molecular weight of 2,600 was added. A structure was obtained and evaluated in the same manner as in Example 1. The results are shown in Table 1. The MFR (A + C) was 160 g / 10 minutes, and the MFR (A + B + C) was 38 g / 10 minutes.

Comparative Example 1
An easily peelable adhesive for polyolefin was obtained in the same manner as in Example 1 except that the ethylene-vinyl acetate copolymer resin (A) described in Example 1 was 35 wt% and the crystalline polypropylene (B) was 45 wt%. As a result, extrusion failure occurred during extrusion lamination, and a stable easily peelable adhesive composition for polyolefin could not be obtained. The results are shown in Table 2. MFR (A + C) was 220 g / 10 minutes, and MFR (A + B + C) was 40 g / 10 minutes.

Comparative Example 2
The ethylene-vinyl acetate copolymer resin (A) described in Example 1 is changed to low density polyethylene (MFR 23 g / 10 min, product name: Petrocene PE208 manufactured by Tosoh Corporation), and low molecular weight ethylene-vinyl acetate copolymer is used. An easy-peelable polyolefin adhesive was obtained in the same manner as in Example 1 except that the coalesced wax (C) was changed to a low molecular weight polyethylene wax (the above-mentioned 151-P), and evaluated in the same manner as in Example 1. The results are shown in Table 1. Although the moldability at the time of extrusion laminating was good and good without the stringing phenomenon, the low temperature heat sealability generation with the PE paper cup and the adhesion with the PP cup were inferior. The results are shown in Table 2. The MFR (A + C) was 34 g / 10 minutes, and the MFR (A + B + C) was 120 g / 10 minutes.

Comparative Example 3
Polyolefin as in Example 1 except that the ethylene-vinyl acetate copolymer resin (A) described in Example 1 was changed to 65 wt% and the low molecular weight ethylene-vinyl acetate copolymer resin (C) was not added. An easily peelable adhesive was obtained. During the evaluation of adhesion to the PE paper cup, stringing and material destruction occurred. The results are shown in Table 2. The MFR (A + C) was 25 g / 10 minutes, and the MFR (A + B + C) was 12 g / 10 minutes.

Comparative Example 4
Easily peelable adhesive for polyethylene as in Example 1 except that the ethylene-vinyl acetate copolymer resin (A) described in Example 1 is 75 wt% and the crystalline polypropylene resin (B) is 5 wt%. Agents were obtained and evaluated as in Example 1. The results are shown in Table 2. Sample formation was not possible due to poor film formation stability during extrusion lamination. The results are shown in Table 2. In addition, MFR (A + C) by mixing | blending of the low density polyethylene and low molecular weight polyethylene wax in a formulation was 110 g / 10min. MFR (A + B + C) was 90 g / 10min.

Comparative Example 5
A resin (manufactured by Tosoh Corporation) having a viscosity of 86,000 mPa · s measured at 180 ° C. using a Brookfield viscometer instead of the low molecular weight ethylene-vinyl acetate copolymer wax described in Example 1 : An easy-release polyolefin adhesive was obtained in the same manner as in Example 1 except that Ultrasen UE720) was used. Stringing and material destruction occurred during the evaluation of adhesion to paper cups. The results are shown in Table 2. In addition, MFR (A + C) was 44 g / 10 minutes, and MFR (A + B + C) was 17 g / 10 minutes.

Claims (7)

Ethylene-vinyl acetate copolymer resin (A) 40-77 wt%, crystalline polypropylene resin (B) 10-40 wt%, GPC with vinyl acetate content measured by JIS K6924-1 in the range of 3-15 wt% Polyethylene wax having a number average molecular weight of 1,000 to 10,000 according to the method, or an ethylene-vinyl acetate copolymer having a viscosity of 50 to 1,000 mPa · s measured at 180 ° C. using a Brookfield viscometer polypropylene for easy peelable adhesive agent characterized by comprising a low molecular weight polyethylene wax (C) 3 to 30 wt% is applied selected. Melt mass flow rate (hereinafter referred to as MFR) of a blend ((A) + (C)) of an ethylene-vinyl acetate copolymer resin (A) and a low molecular weight polyethylene wax (C) measured in accordance with JIS K6922-1 (A + C)) is 40 to 400 g / 10 min, and the melt mass flow rate (hereinafter referred to as MFR (hereinafter referred to as MFR)) of all the formulations ((A) + (B) + (C)) measured according to JIS K6922-1 a + B + C)) is poly propylene for peelable adhesive according to claim 1, characterized in that a 10 to 60 g / 10 min. Ethylene - vinyl acetate copolymer resin (A) is, for polypropylene according to claim 1 or 2 melt mass flow rate measured in accordance with JIS K6922-1 is characterized in that it is a 10 to 50 g / 10 min Easy peelable adhesive. The crystalline polypropylene resin (B) is a random copolymer of propylene and ethylene, and the melt mass flow rate measured according to JIS K7210 is 0.5 to 10 g / 10 min. polypropylene for peelable adhesive according to 1 or 2. The low molecular weight polyethylene wax (C) is an ethylene-vinyl acetate copolymer having a viscosity of 50 to 1,000 mPa · s measured at 180 ° C. using a Brookfield viscometer. The easily peelable adhesive for polypropylene according to any one of -4. The lid | cover material which has the easily peelable adhesive agent for polypropylenes in any one of Claims 1-5 on an at least single side | surface . The lid material according to claim 6, which is a lid material for a polypropylene container .