JP6357791B2 - Easy peelable film - Google Patents

Description

  The present invention relates to an easily peelable film, and more particularly to an easily peelable film for a lid material suitable for a container, and more particularly, an easily peelable film for a lid material suitable for a paper container. The present invention relates to an easily peelable film that is excellent in adhesive strength retention at, has no fluffing of a paper container at the time of peeling, and has an excellent antistatic effect.

  Conventionally, plastic containers such as polypropylene and polystyrene and containers mainly made of paper have been used for packaging foodstuffs and industrial parts, and the lid has an appropriate seal strength and is smooth when peeled. A so-called easily peelable film having peelability is required. In particular, a cover tape used for a carrier tape used for transporting small electronic components is required to have strength retention during storage and stability of peel strength during peeling. Further, in the case of a carrier tape using paper, not only the stability of the peel strength but also the fluffing of the paper fiber at the time of peeling is required.

  In the case of a carrier tape using paper, since the adhesive layer becomes paper, even low-density polyethylene can be used as an adhesive for the cover tape. However, low-density polyethylene is inferior in low-temperature heat sealability, so it is also possible to use an ethylene-vinyl acetate copolymer. In this case, even if the low temperature heat sealability is improved, the adhesive strength is insufficient. Therefore, in order to improve the low temperature heat sealability and increase the adhesive strength, it is conceivable to add a tackifier such as petroleum hydrocarbon resin to the ethylene-vinyl acetate copolymer and use it as an adhesive for the cover tape. (For example, refer to Patent Document 1). This uses an ethylene-vinyl acetate copolymer with a vinyl acetate content of 6% or less, and by adding 10-60 parts of a tackifier, the paper substrate does not fuzz during peeling and is inserted into the paper substrate. This suppresses the adhesion of small electronic components. Further, it is considered that a tackifier resin and a low molecular weight ethylene-vinyl acetate copolymer are added to an ethylene-vinyl acetate copolymer and used as an adhesive for a cover tape (see, for example, Patent Document 2). However, in the current situation where rapid high-speed filling has progressed, a low temperature sealing property of 130 ° C. or lower cannot be satisfied.

In addition, electronic parts filled in carrier tapes are now transported and stored in various regions, especially in cold regions where the temperature is below freezing, such as minus 20 ° C. There is a problem that the adhesive strength of the heat-sealed portion is lowered, the heat-sealed portion is peeled off, and parts are spilled from the carrier tape.
In addition, when blended with a large amount of tackifier such as petroleum hydrocarbon resin added to ethylene-vinyl acetate copolymer, even if heat seal strength is improved, paper fluff is an important adhesive performance required for cover tape. It was impossible to satisfy that there was no. Furthermore, the adhesive itself is more likely to be blocked by increasing the amount of tackifier added, and the cover tape in the wound state is blocked, or after being attached to the carrier tape, the electronic component as a content adheres to the cover tape. There was a problem that it would end up.

  Further, anti-static, which is another important performance, is required to be further stabilized due to the miniaturization of parts. Generally, imparting performance by kneading a surfactant typified by glycerin fatty acid ester is performed. However, when glycerin fatty acid ester is used alone, the antistatic performance is deteriorated due to aging. Cover tapes that are easy to occur and have stable antistatic properties have not been obtained.

No. 3-37760 JP 2009-35645 A

  However, the easily peelable film proposed in Patent Document 1 or 2 has not been able to satisfy a low temperature sealing property of 130 ° C. or less in the current situation where rapid filling has progressed dramatically. In addition, there is a problem that the adhesive strength is poorly maintained in a cold environment where the temperature is below freezing point such as minus 20 ° C. or in a low temperature environment during transportation.

  For this reason, the easily peelable film which can solve these subjects was desired.

  Therefore, the present invention aims to solve the above problems and provide an easily peelable film satisfying low temperature heat sealability and adhesive strength retention in a low temperature environment, prevention of fluffing of paper containers during peeling, and antistatic effect. To do.

  As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that an appropriate amount of a specific ethylene-vinyl acetate copolymer, a tackifier resin, a low molecular weight ethylene-vinyl acetate copolymer, and an antistatic agent are mixed. By using this, it is found that the film becomes an easily peelable film excellent in low temperature heat sealability, adhesive strength retention in a low temperature environment, fluffing of paper containers at the time of peeling, and antistatic properties, and the present invention is completed. It reached.

  That is, the present invention is an ethylene having a vinyl acetate content measured by JIS K6924-1 in the range of 3 to 18% by weight and a melt mass flow rate measured by JIS K6924-1 in the range of 5 to 40 g / 10 min. -5 to 20 parts by weight of a tackifier resin (B) having a softening point of 90 ° C to 125 ° C measured by the ring and ball method with respect to 100 parts by weight of the vinyl acetate copolymer (A), 180 using a Brookfield viscometer An antistatic agent (D) containing 3 to 10 parts by weight of a low molecular weight ethylene-vinyl acetate copolymer (C) having a viscosity of 50 to 1,000 mPa · s measured at ° C, at least a glycerol fatty acid ester and an amine compound; The present invention relates to an easily peelable film having an adhesive layer containing 2 to 1 part by weight and a supporting base material layer.

  The present invention is described in detail below.

  The ethylene-vinyl acetate copolymer (A) of the present invention is an ethylene-vinyl acetate copolymer (EVA) obtained by a known production method, and is excellent in low-temperature heat sealability and anti-blocking performance. Therefore, the vinyl acetate content measured according to JIS K 6924-1 is in the range of 3 to 18% by weight, and particularly preferably 6 to 15% by weight. When the vinyl acetate content is less than 3% by weight, the low-temperature heat sealability is inferior, which is not preferable. When the vinyl acetate content exceeds 18% by weight, the blocking property and antistatic performance are deteriorated, which is not preferable. In order to be excellent in low temperature heat sealing performance and fluff prevention of paper containers, the melt mass flow rate measured at a temperature of 190 ° C. and a load of 21.18 N in accordance with JIS K 6924-1 is 5 to 40 g / 10 min. It is in the range, and is particularly preferably 5 to 30 g / 10 minutes. If the melt mass flow rate is less than 5 g / 10 minutes, the low temperature heat sealability, heat seal strength, and fuzzing prevention of paper containers are inferior, which is not preferable. If the melt mass flow rate exceeds 40 g / 10 minutes, the molding stability is poor. This is not preferable because the blocking strength increases.

  The tackifier resin (B) of the present invention only needs to have a softening point of 90 ° C. to 125 ° C. measured by the ring and ball method and impart low temperature heat sealability and adhesive strength retention in a low temperature environment, Examples thereof include aliphatic petroleum resins, aromatic petroleum resins, alicyclic hydrogenated petroleum resins, copolymerized petroleum resins, rosin resins, terpene resins, styrene resins, coumarone-indene resins, and the like. These can be used alone or in combination of two or more. Among these, alicyclic hydrogenated petroleum resins are particularly preferable because they are excellent in low-temperature heat sealability and adhesive strength retention in a low-temperature environment, and are excellent in transparency and low odor.

  The softening point of the tackifier resin (B) of the present invention is such that the softening point measured by the ring and ball method is in the range of 90 to 125 ° C, particularly preferably 100 ° C to 125 ° C. When the softening point is less than 90 ° C., the blocking resistance is inferior, and when it exceeds 125 ° C., the adhesive strength retention in a low temperature environment is inferior.

  The blending amount of the tackifier resin (B) is 5 to 20 parts by weight with respect to 100 parts by weight of the ethylene-vinyl acetate copolymer (A) in order to be excellent in low temperature heat sealability and heat seal strength. It is in a range, and it is preferable that it is 10-20 weight part especially. When the amount is less than 5 parts by weight, the low-temperature heat sealability and heat seal strength are insufficient, and when the amount exceeds 20 parts by weight, fuzz occurs in the paper container at the time of peeling.

  The low molecular weight ethylene-vinyl acetate copolymer (C) of the present invention is an ethylene-vinyl acetate copolymer (EVA) obtained by a known production method, which provides a stable adhesive strength and provides a paper upon peeling. The viscosity measured at 180 degrees using a Brookfield viscometer is 50 to 1,000 mPa · s in order to suppress the fuzz of the container. Preferably it is 100-500 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 compound is poor. If it exceeds 1,000 mPa · s, the fluffing of the paper container at the time of peeling is improved. Less effective.

  The antistatic agent (D) of this invention consists of an antistatic agent containing the mixture which consists of a glycerol fatty acid ester and an amine compound at least.

  The glycerin fatty acid ester has the general formula (I)

It is a compound obtained by esterification reaction of the fatty acid and glycerin represented by R ₁ COOH. In the formula, R ₁ is generally a linear or branched alkyl group or alkenyl group, and a carbon number of 8 to 22 is preferable because sufficient antistatic performance can be obtained. Examples of the compound include lauric acid monoglyceride, palmitic acid monoglyceride, stearic acid monoglyceride, oleic acid monoglyceride, linoleic acid monoglyceride and the like, and these compounds can be used either alone or in a mixture. As the glycerin fatty acid ester, Riquemar P-100, S-100 (manufactured by Riken Vitamin), Rhedol MS-50 (manufactured by Kao), Monogly D, M, I (manufactured by NOF Corporation) and the like are commercially available.

Any amine compound can be used as long as it belongs to the category of an antistatic agent and has a function of preventing the easily peelable film from being charged. Examples of the amine compound include aliphatic amines, aliphatic amine derivatives, sulfonic acid amine salts, and the like. Since the antistatic effect is excellent, aliphatic amines and aliphatic amine derivatives are preferable.
Examples of the aliphatic amine include saturated aliphatic amines having 6 to 30 carbon atoms, unsaturated aliphatic amines, etc., preferably primary aliphatic amines or secondary aliphatic amines,
Hexylamine, octylamine, isooctylamine, caprylamine, caproleylamine, laurylamine, myristylamine, myristolamine, heptadecylamine, palmitylamine, isopalmityrylamine, palmitolylamine, stearylamine, isostearyl Primary aliphatic amines such as amine, aralkylamine, ricinoleylamine, linoleylamine, behenylamine, oleylamine, lignoceylamine, N, N-dicaprylamine, N, N-dioctylamine, N, N-dicapryl Mention may be made of secondary aliphatic amines such as amines, N, N-dicaproylamine, N, N-dilaurylamine, N, N-dimyristylamine. Examples of aliphatic amine derivatives include polyoxyethylene alkylamine, decylethanolamine, dodecyldiethanolamine, tetradecyldiethanolamine, hexadecyldiethanolamine, octadecyldiethanolamine, eicosyldiethanolamine, and the like, polyoxyethylene alkylamine, polyoxyethylene stearylamine, Dodecyl diethanolamine, tetradecyl diethanol amine, hexadecyl diethanol amine, and octadecyl diethanol amine are preferable, and polyoxyethylene alkyl amine is particularly preferable. As a polyoxyethylene alkylamine, for example. A trade name Armostat 310 (manufactured by Lion Corporation) and the like can be mentioned. These amine compounds can be used alone or in combination of two or more.

  The mixing ratio of the glycerin fatty acid ester and the amine compound is preferably 1/3 to 3/1 in weight ratio.

  The blending amount of the antistatic agent (D) of the present invention is excellent in antistatic performance, low-temperature sealability, and adhesive strength retention in a low-temperature environment, so that ethylene-vinyl acetate copolymer (A) 100 is used. It is in the range of 0.2 to 1 part by weight with respect to parts by weight, and particularly preferably 0.3 to 0.6 parts by weight. When the amount is less than 0.2 parts by weight, the antistatic effect is insufficient. When the amount exceeds 1 part by weight, the low-temperature sealing property and the adhesive strength retention in a low-temperature environment are inferior.

  As long as the effects of the present invention are not impaired, the present adhesive further includes other thermoplastic resins and rubbers, light stabilizers, ultraviolet absorbers, nucleating agents, lubricants, antioxidants, antiblocking agents, and fluidity improvement. An agent, a release agent, a flame retardant, a colorant, an inorganic neutralizer, a hydrochloric acid absorbent, a filler conductive agent, and the like may be used.

  The method for preparing the blend of the present invention is as follows: an ethylene-vinyl acetate copolymer (A), a tackifier resin (B), a low molecular weight ethylene-vinyl acetate copolymer (C), and an antistatic agent (D). A method of pre-blending with a mixer such as a Henschel mixer or a tumbler and melt-kneading with a single-screw or twin-screw extruder is possible. The antistatic agent can be kneaded at a high concentration in a polyolefin resin in advance to form a master batch, and the master batch can be added at the time of extrusion lamination processing. The polyolefin resin used as the base of the masterbatch is preferably an ethylene-vinyl acetate copolymer resin, more preferably the ethylene-vinyl acetate copolymer (A) used in the present invention.

  As the support base material layer used in the easily peelable film of the present invention, any material can be used as long as it can support the adhesive layer. For example, there are a biaxially stretched polyester film, a polypropylene film, and a polyamide film. It is also possible to use a two-layer support substrate in which, for example, a polyethylene-based resin is extruded onto the anchor coating agent surface after applying an anchor coating agent on a biaxially stretched polyester film, polypropylene film or polyamide film in advance. it can. Also, after applying an anchor coating agent on a polyester film, polypropylene film, or polyamide film that has been biaxially stretched by tandem lamination, polyethylene resin or the like is extruded onto the anchor coating agent surface using the first extruder. The two-layer film can be used as a supporting substrate, and an easily peelable film can be obtained by extruding an adhesive with an in-line second extruder.

  The easily peelable film of the present invention includes an adhesive layer and a support base material layer. You may have intermediate layers, such as a polyethylene-type resin, between an adhesive bond layer and a support base material layer.

  For the biaxially stretched polyester film, etc., which will be the support base layer, an antistatic agent is applied to the surface different from the surface where the adhesive or polyethylene resin is bonded, or kneaded into the raw material in advance when forming the base film. It is preferable to keep the antistatic performance because it is effective in improving the antistatic performance. As the polyethylene-based resin serving as the intermediate layer, low density polyethylene, ultra-low density polyethylene, linear low density polyethylene, high density polyethylene, and the like can be used. In particular, low density polyethylene is preferable because it is excellent in extrusion laminating suitability. Further, ultra-low density polyethylene is preferable because the cushioning property of an easily peelable film is exhibited. Moreover, an antistatic agent can also be mix | blended with the polyethylene-type resin and anchor coating agent which are used for a support base material layer.

  In addition, the adhesive layer of the present invention can be formed in advance as a single layer or a multilayer film by cast molding or inflation molding, and an easily peelable film can be prepared by a support substrate, dry lamination, and sandwich lamination.

  The easily peelable film of the present invention is used for a lid material suitable for a container, and is particularly suitable for a paper container. Since there is no fluffing on the paper container and it has excellent antistatic performance, it can be effectively used in fields where these performances are required. For example, it can be used as a lid (generally referred to as a cover tape) for a continuous tape-like container (generally referred to as a carrier tape) containing electronic components, microchips, and the like. There are plastic tapes using polystyrene or the like as carrier tapes, but carrier tapes provided with holes or depressions for inserting parts into cardboard are often used. For example, a microcarrier is inserted into a hole or dent in a paper carrier tape, and an easily peelable film serving as a cover tape is heat-bonded in a short time so as to serve as a cover material. Then, it is carried to another process, and it moves to the process of taking out the microchip while peeling the easily peelable film at high speed. In this way, the cover tape has a low temperature sealing property that can be heat-bonded in a short time, prevents flaking of paper fibers from adhering to microchips, etc., and prevents fluffing at the time of peeling. Therefore, the present invention can provide a peelable film that can sufficiently satisfy these requirements.

  The easy-peelable film of the present invention is excellent in low-temperature heat-sealability and adhesive strength retention in a low-temperature environment, has no fluffing of paper containers at the time of peeling, is excellent in antistatic effect, and suitable for containers It has excellent suitability as an easily peelable film for lid materials, particularly as an easily peelable film for lid materials suitable for paper containers.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these Examples. The measurement methods used in the examples are shown below.

~ Melt Mass Flow Rate (MFR) ~
The MFR of the ethylene-vinyl acetate copolymer (A) was measured according to JIS K6922-1.

-Viscosity measurement of low molecular weight ethylene-vinyl acetate copolymer-
Measured using a Brookfield viscometer.
Evaluation of characteristics of easily peelable film -Measurement of low temperature heat sealability-
The adhesive surface of the easily peelable film and a paper carrier (made in Korea) are overlapped, and a taping tester (manufactured by Vanguard Systems Co., Ltd., VS-120 type), a U-shaped seal bar (0.5 mm width × Using two types, seal bar length 8.2mm), pressurizing and heating continuously under the conditions of 130 ° C, 0.1MPa, 0.1 seconds, seal pitch 8mm so that the end part of the seal bar slightly overlaps did.

  After standing to cool, the seal strength was continuously measured for a length of 150 mm under the conditions of a peeling angle of 180 degrees and a peeling speed of 300 mm / min, and the average value was obtained. The low temperature heat sealability is evaluated to be 0.2 N / mm or more.

○: 0.2 N / mm or more ×: less than 0.2 N / mm
The adhesive surface of the easily peelable film and the paper carrier (made in Korea) are overlapped, and the heat seal strength is 0.3 N / mm using a taping tester (manufactured by Vanguard Systems Co., Ltd., model VS-120). The heat seal conditions were adjusted so that pressure bonding was performed.

  After standing to cool, peeling was performed under conditions of a peeling angle of 180 degrees and a peeling speed of 300 mm / min, and the adhesive surface of the easily peelable film and the surface of the carrier tape were visually confirmed, and the peeled state was evaluated in two stages.

○: The carrier tape is not fuzzy and no paper fibers are adhered to the film surface (good)
X: The carrier tape is fuzzy, and the paper fiber adheres to the film surface (defective)
~ Measurement of adhesive strength after storage at minus 20 ℃ ~
Adhesive surface of easy peelable film and paper carrier (made in Korea) are overlapped, taping tester (manufactured by Vanguard Systems Co., Ltd., VS-120 type), U-shaped seal bar (0.5mm width x 2 pieces) Using a mold and a seal bar length of 8.2 mm), pressure and heat bonding were continuously performed under the conditions of 130 ° C., 0.1 MPa, 0.1 second, and a seal pitch of 8 mm so that the end portions of the seal bar slightly overlapped. After standing to cool, the seal strength was continuously measured for a length of 150 mm under the conditions of a peeling angle of 180 degrees and a peeling speed of 300 mm / min, and the average value was obtained as an initial value. The bonded sample is stored in a low temperature bath at −20 ° C. for one day, and the sample is taken out and allowed to stand at room temperature, and then the seal strength is continuously applied for 150 mm length at a peeling angle of 180 degrees and a peeling speed of 300 mm / min. The average value was determined as the adhesive strength after storage at -20 ° C.

As the adhesive strength retention after storage at −20 ° C., a value obtained by subtracting the initial value from the adhesive strength after storage at −20 ° C. was obtained. It was evaluated that the adhesive strength retention after storage at -20 ° C was -0.05 to 0 N / mm.
-Measurement of antistatic performance-
After extrusion lamination processing, the easily peelable film (F) was stored for 3 days under conditions of 23 ° C. and 50% RH, and then the surface resistivity value of the adhesive surface was 23 ° C. and 50% RH in accordance with JIS K6911. Measured at conditions. Moreover, after storing an easily peelable film (F) for 30 days on 23 degreeC and 50% RH conditions as stability over time, the surface specific resistance value of an adhesive surface is 23 degreeC and 50% based on JISK6911. The measurement was performed under the conditions of RH.
The surface specific resistance value is preferably 10 ¹² Ω or less.

~ Measurement of blocking ~
Two easy-peelable films (F) were prepared in the form of 25 mm-wide strips, the adhesive surface and the biaxially stretched polyester film were overlapped, and a 1 kg load was applied and left in an oven at 40 ° C. for 24 hours. The subsequent shear peel strength was measured.

Example 1
As the ethylene-vinyl acetate copolymer (A), a resin having a vinyl acetate content of 6% and a melt mass flow rate measured by JIS K6924-1 of 28 g / 10 min (trade name Ultrasen 539 manufactured by Tosoh Corporation) is used. used. As the tackifier resin (B), hydrogenated petroleum resin (B1) (trade name Alcon P125, softening point 125 ° C., manufactured by Arakawa Chemical Co., Ltd.) is 15 per 100 parts by weight of the ethylene-vinyl acetate copolymer (A). A resin having a viscosity of 240 mPa · s measured at 180 ° C. using a Brookfield viscometer as a low molecular weight ethylene-vinyl acetate copolymer (C) (Special Ultrasen 7A55A manufactured by Tosoh Corporation. Melt mass flow) 6 parts by weight of about 30,000 g / 10 min late, number average molecular weight 2,500), antistatic agent (D) stearic acid monoglyceride (trade name Riquemar S-100, manufactured by Riken Vitamin Co., Ltd.) and amine 0.6 parts by weight of an antistatic agent (D1) in which a compound (trade name Armostat 310 manufactured by Lion Corporation) was mixed at a ratio of 2/1 was used. In consideration of thermal stability, 0.05 parts by weight of a phenolic antioxidant (trade name: Irganox 1010, manufactured by BASF Corporation) was added to 100 parts by weight of the adhesive.
The adhesive composition was pre-blended with a tumbler mixer and melt kneaded at 160 ° C. using a twin screw extruder to obtain the present adhesive pellet (E). The ratio is shown in Table 1.

  In order to prepare an easily peelable film using the present adhesive pellet (E), a low-density polyethylene is applied to a polyester film (25 μm thickness) biaxially stretched in advance using a urethane-based anchor coat agent to a resin temperature of 310. Prepare a support base material that has been extruded and laminated to a thickness of 15 μm at ℃, and then apply this adhesive pellet (E) to the low-density polyethylene side of the support base material at a resin temperature of 200 ° C. to a thickness of 15 μm. Then, an easily peelable film (F) was obtained. The obtained easily peelable film was evaluated, and the results are shown in Table 2.

Example 2
In Example 1, an easily peelable film was obtained in the same manner as in Example 1 except that 0.3 part by weight was used instead of 0.6 part by weight of the antistatic agent (D). The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2.

Example 3
In Example 1, as the ethylene-vinyl acetate copolymer (A), instead of the resin (A1) having a vinyl acetate content of 6% and a melt mass flow rate measured by JIS K6924-1 of 28 g / 10 min, ethylene The same as Example 1 except that an ethylene vinyl acetate copolymer (A2) (Tosoh Corp. Ultrasen 625) having a vinyl acetate content of 15% and a melt mass flow rate of 14 g / 10 min was used. An easily peelable film was obtained. The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2.

Example 4
In Example 1, instead of the softening point 125 ° C. of the tackifier (B), an easily peelable film was obtained in the same manner as in Example 1 except that 90 ° C. (Arukawa Chemical Co., Ltd., Alcon M90) was used. . The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2.

Comparative Example 1
In Example 1, instead of the antistatic agent (D1) as the antistatic agent (D), stearic acid monoglyceride (D2) (trade name Riquemar S-100 manufactured by Riken Vitamin Co., Ltd.) was used in an amount of 0.6 parts by weight. An easily peelable film was obtained in the same manner as in Example 1. The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2. The obtained easily peelable film was inferior in adhesive strength retention after storage at -20 ° C and antistatic property after 30 days.

Comparative Example 2
Example 1 except that instead of the antistatic agent (D1) as the antistatic agent (D1) in Example 1, 0.6 parts by weight of the amine compound (D3) (trade name Armostat 310 manufactured by Lion Corporation) was used. In the same manner as above, an easily peelable film was obtained. The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2. The obtained easily peelable film was inferior in peeling appearance and antistatic property.

Comparative Example 3
In Example 1, instead of the antistatic agent (D1) as the antistatic agent (D), 0.35 part by weight of stearic acid monoglyceride (trade name Riquemar S-100 manufactured by Riken Vitamin Co., Ltd.), stearic acid diglyceride (RIKEN vitamin) Antistatic agent (D4) in which 0.24 parts by weight of product name Riquemar S-71D manufactured by Co., Ltd. and 0.01 parts by weight of polyoxyethylene lauryl ether (product name Nonion K-220 manufactured by NOF Corporation) were mixed. An easily peelable film was obtained in the same manner as in Example 1 except that the amount was 0.6 parts by weight. The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2. The obtained easily peelable film was inferior in low temperature sealability and adhesive strength retention after storage at -20 ° C.

Comparative Example 4
In Example 1, instead of the tackifier (B1) as the tackifier (B), hydrogenated petroleum resin (B3) (trade name Alcon P140, manufactured by Arakawa Chemical Co., Ltd., softening point 140 ° C.) was 15 parts by weight. Except for this, an easily peelable film was obtained in the same manner as in Example 1. The ratio is shown in Table 1. The obtained easily peelable film was evaluated, and the results are shown in Table 2. The obtained easily peelable film was inferior in low temperature sealability and adhesive strength retention after storage at -20 ° C.

  The easily peelable film of the present invention has a specific ethylene-vinyl acetate copolymer, a tackifier resin, a low molecular weight ethylene-vinyl acetate copolymer, an adhesive layer containing an antistatic agent, and a support base layer. Because it is a peelable film, it is an easily peelable film with excellent low-temperature heat-sealing properties, adhesive strength retention in low-temperature environments, fluffing of paper containers during peeling, and antistatic properties. It is expected to be applied as an easily peelable film for a lid material for containers for transporting and storing industrial parts such as.

Claims (2)

An ethylene-vinyl acetate copolymer having a vinyl acetate content measured by JIS K6924-1 in the range of 3 to 18% by weight and a melt mass flow rate measured by JIS K6924-1 in the range of 5 to 40 g / 10 min. (A) The viscosity measured at 180 ° C. using a Brookfield viscometer is 5 to 20 parts by weight of a tackifier resin (B) having a softening point of 90 ° C. to 125 ° C. measured by the ring and ball method with respect to 100 parts by weight. 3 to 10 parts by weight of a low molecular weight ethylene-vinyl acetate copolymer (C) that is 50 to 1,000 mPa · s, 0.2 to 1 part by weight of an antistatic agent (D) containing at least a glycerin fatty acid ester and an amine compound An easily peelable film comprising an adhesive layer and a supporting substrate layer. The easily peelable film according to claim 1, which is a cover tape for a carrier tape, which is a paper container for transporting electronic components.