JP6919218B2 - Anti-slip film and heavy-duty packaging film - Google Patents

Description

The present invention relates to an anti-slip film and a packaging material, and more particularly to an anti-slip heavy-weight packaging film having low slipperiness and an excellent balance of heat seal strength, impact resistance, bag drop strength and rigidity.

Polyethylene films are often used for packaging. Among them, heavy-weight packaging bags are required to be not torn even when a large amount of heavy-weight materials such as fertilizers and grains, such as several tens of kilograms, are packaged, and are usually produced with a film thickness of about 60 to 200 μm. Since this heavy-duty packaging bag is generally stacked high in many stages, it may collapse and slip off. In order to prevent this, it is required that the surface of the bag does not slip properly.

In order to meet such demands, there is a method of making the surface of the bag uneven to prevent it from slipping off, but it is necessary to introduce equipment to make the surface of the bag uneven, resulting in increased cost, reduced productivity, and processing process. There were problems such as the need for addition and surface shape inspection.

On the other hand, in order to impart a function of preventing slipping on the surface of the bag, a method of lowering the slipperiness by the physical characteristics of the film itself is adopted. As such a method, an anti-slip film using an adhesive layer on the surface is known (see Patent Document 1). As yet another method, a method of suppressing film blocking while imparting anti-slip properties by using a special additive is known (see Patent Documents 2 and 3).

Japanese Unexamined Patent Publication No. 2016-30804 Japanese Unexamined Patent Publication No. 2004-115600 Japanese Unexamined Patent Publication No. 2014-216468

However, as in Patent Document 1, when an anti-slip film having an adhesive layer on the surface is used for a heavy-weight packaging bag, pressure is applied by the heavy-weight material and the heavy-weight packaging is under high temperature and high humidity. It is not preferable because the adhesive layers, which are anti-slip layers, may adhere to each other because they are placed in a stacked state. Further, the additives used in Patent Documents 2 and 3 are relatively expensive, and not only the cost of the film increases, but also each effect may be lost due to bleeding or dropping of the additives. Therefore, no special additives are used, no processing such as embossing is required, the material itself has excellent anti-slip properties, and it is suitable for heavy-duty packaging films such as high heat seal strength, impact strength, and bag drop strength. An anti-slip film suitable for a packaging material having the required properties has been desired.

In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a slip-preventing heavy-duty packaging film having low slipperiness of the bag surface, high rigidity, high heat-sealing property, and impact resistance when dropped. There is.

As a result of diligent studies to solve the above problems, the present inventor controls the resin used for at least one outer surface layer of the film by limiting it to a combination of resins having specific physical property values, thereby making the film surface slippery. It has been found that the above-mentioned problems can be solved by exhibiting high rigidity, high heat-sealing property, and impact resistance when dropped. Further studies have been made on these findings, and the present invention has been completed.

That is, according to the first invention of the present invention, at least the outer surface layer is ^{a metallocene system having a density of 0.860 to 0.910 g / cm 3} and a melt flow rate of 0.1 to 10 g / 10 minutes at 190 ° C. It is composed of a resin component containing 15 to 75% by weight of a polyethylene-based resin polymerized by a catalyst, and the outer surface layer resin component as a whole has a density of 0.911 to 0.940 g / cm ³ and a melt flow rate at 190 ° C. Provided is an anti-slip film, which comprises an anti-slip film characterized by being 0.1 to 5 g / 10 minutes.

Further, according to the second invention of the present invention, the first invention is characterized in that the inclination angle when the outer surface layers are brought into contact with each other and inclined and starts to slide is 22 ° to 60 °. Anti-slip film is provided.

Further, according to the third invention of the present invention, the anti-slip film characterized by being a multilayer film is provided in the first or second invention.

Further, according to the fourth invention of the present invention, in the third invention, a norbornene-based copolymer (COC) obtained by copolymerizing a norbornene-based monomer and an α-olefin in a layer adjacent to at least the outer surface layer is provided. An anti-slip film characterized by inclusion is provided.

Further, according to the fifth invention of the present invention, there is provided an anti-slip film which is an inflation film formed by performing inflation molding using the resin composition described in any one of the first to fourth inventions. Will be done.

Further, according to the sixth invention of the present invention, there is provided a heavy-weight packaging film characterized by using the anti-slip film described in any one of the first to fifth inventions.

Further, according to the seventh aspect of the present invention, there is provided a sixth heavy object packaging film, characterized in that the thickness of the film is 60 μm or more.

It is the schematic which shows the cross section of an example of the anti-slip film of this invention.

Hereinafter, each item of the anti-slip heavy-weight packaging film of the present invention will be described in detail.
In the anti-slip heavy-weight packaging film of the present invention, the anti-slip resin at least on the outer surface layer has a density of 0.860 to 0.910 g / cm ³ , and a melt flow rate at 190 ° C. of 0.1 to 10 g /. It is composed of a resin component containing 15 to 75% by weight of a polyethylene resin polymerized by a metallocene catalyst for 10 minutes, and the overall resin component has a density of 0.911 to 0.940 g / cm ³ and a melt flow at 190 ° C. The late is 0.1 to 5 g / 10 minutes.

Within the scope of the present invention, the film may be single-layered or multi-layered. However, considering the moldability, the load on the motor of the molding machine, the strength of the film, and the like, it is preferable to have multiple layers. Further, since anti-slip property is required only on the surface, the thickness of the surface can be reduced within the range in which anti-slip property is exhibited. Further, it is desirable that both surfaces have the same resin composition from the viewpoint of preventing curling of the film. Hereinafter, each layer in the case of a multilayer film will be described with reference to examples.

1. 1. Resin of each layer (1) Outer surface layer (layer with anti-slip property)
The outer surface layer is a layer having anti-slip properties, constitutes a layer exposed to the surface when formed into a bag, and when the film has a single-layer structure, the film consists of only the main layer. The first layer, which is the outer surface layer of the anti-slip heavy-duty packaging film of the present invention, has a density of 0.860 to 0.910 g / cm ³ and a melt flow rate of 0 at 190 ° C. in order to impart anti-slip properties. It is composed of a resin component containing 15 to 75% by weight of a polyethylene resin polymerized by a metallocene catalyst of 1 to 10 g / 10 minutes, and the density of the resin component as a whole is 0.911 to 0.940 g / cm ³ , 190. The melt flow rate at ° C. is required to be 0.1 to 5 g / 10 minutes. By adding a resin having a low density, anti-slip properties are imparted to the outer surface layer, and the physical properties of the entire resin constituting the outer surface layer are also important for heavy-duty packaging applications.

The resin that imparts anti-slip properties preferably has a density of 0.870 to 0.910 g / cm ³ , a melt flow rate at 190 ° C. of 0.2 to 7 g / 10 minutes, and more preferably a density of 0. The melt flow rate at .880 to 0.910 g / cm ³ and 190 ° C. is 0.3 to 5 g / 10 minutes. If the density is ^{less than 0.870 g / cm 3} , blocking is more likely to occur when the bags are stacked. Further, if the melt flow rate is smaller than 0.2 g / 10 minutes, the extrusion load becomes large and the workability deteriorates, and if the melt flow rate is larger than 7 g / 10 minutes, the physical characteristics of the film may deteriorate.

The polyethylene-based resin contained in the outer surface layer is polymerized by a metallocene-based catalyst. By using a metallocene-based catalyst, the molecular weight distribution of the polyethylene-based resin can be narrowed. As the metallocene catalyst, various known catalysts used for olefin polymerization can be used. Specifically, the metallocene catalysts described in JP-A-58-19309, JP-A-59-95292, JP-A-60-35006, JP-A-3-163088 and the like are exemplified. .. Specific polymerization methods include a slurry method in the presence of a catalyst, a gas phase flow bed method and a solution method, or ^{a high-pressure bulk at a pressure of 200 kg / cm 2} (19.6 MPa) or more and a polymerization temperature of 100 ° C. or more. A polymerization method and the like can be mentioned. A preferred production method includes high pressure bulk polymerization.

(2) Intermediate layer The second layer, which is an intermediate layer when the anti-slip heavy-duty packaging film has a multi-layer structure, is not particularly limited as long as it is a resin that satisfies the physical characteristics for heavy-duty packaging. Furthermore, other functions can be added as long as they satisfy the physical characteristics of heavy-duty packaging applications. For example, by using a polyethylene resin containing a cyclic olefin resin as an intermediate layer, it is possible to provide a heavy-duty package having an easily tearable function.

(A) Cyclic olefin resin Examples of the cyclic olefin resin used in the second layer of the anti-slip heavy-duty packaging film include norbornene-based polymers, vinyl alicyclic hydrocarbon polymers, and cyclic conjugated diene polymers. Can be mentioned. Among these, norbornene-based polymers are preferable. The norbornene-based polymer includes a ring-opened polymer of a norbornene-based monomer (hereinafter, also referred to as “COP”), a norbornene-based copolymer obtained by copolymerizing a norbornene-based monomer and an α-olefin such as ethylene. Coalescence (hereinafter, also referred to as "COC") and the like can be mentioned. Also, hydrogenated COP and COC can be used.

The COC includes linear monomers such as α-olefins such as ethylene, propylene, butene-1, penten-1, hexene-1, heptene-1, and octene-1, and cyclic monomers such as tetracyclododecene and norbornene. Examples thereof include a cyclic olefin copolymer obtained from. More specifically, the linear monomer and monocycloalkene and bicyclo [2.2.1] -2-heptene (norbornene) having 3 to 20 carbon atoms and their derivatives, tricyclo [4.3.0.1] ^2,5 ] -3-decene and its derivatives, tetracyclo [4.4.0.1. ^2,5 . 1 ^{7, 10} ] -3-dodecene and its derivatives, pentacyclo [6.5.1.1 ^3,6 . 0 ^2,7 . 0 ^9,13] -4-pentadecene and derivatives thereof, pentacyclo [7.4.0.1 ^{2,5. 19 and 12} . 0 ^8,13] -3-pentadecene and derivatives thereof, pentacyclo [8.4.0.1 ^{2,5. 19 and 12} . 0 ^8,13] -3-hexadecene and derivatives thereof, pentacyclo [6.6.1.1 ^{3, 6.} 0 ^2,7 . 0 ^9,14] -4-hexadecene and derivatives thereof, hexacyclo [6.6.1.1 ^{3, 6.} 1 ^{10, 13} . 0 ^2,7 . 0 ^9,14] -4-heptadecene and derivatives thereof, heptacyclo [8.7.0.1 ^2,9. 1 ^{4, 7} . 1 ^{11, 17} ． 0 ^3,8 . 0 ^12,16 ] -5-eikosen and its derivatives, heptacyclo [8.7.0.1 ^3,6 . 1 ^{10, 17} ． 1 ^{12, 15} ． 0 ^2,7 . 0 ^11,16 ] -4-eicosene and its derivatives, heptacyclo [8.8.0.1 ^2,9 . 1 ^{4, 7} . 1 ^{11, 18} . 0 ^3,8 . 0 ^12,17 ] -5-Heneikosen and its derivatives, octacyclo [8.8.0.1 ^2,9 . 1 ^{4, 7} . 1 ^{11, 18} . 1 ^{13, 16} . 0 ^3,8 . 0 ^12,17 ] -5-docosen and its derivatives, nonacyclo [10.9.1.1 ^4,7 . 1 ^{13, 20} . 1 ^{15, 18} . 0 ^2,10 . 0 ^3,8 . 0 ^{12, 21} . 0 ^{14,19] -5-pentacosene} and a cyclic olefin copolymer comprising a copolymer of a cyclic olefin of the derivatives. The linear monomer and the cyclic monomer may be used alone or in combination of two or more. Moreover, such a cyclic olefin copolymer can be used alone or in combination. Further, the COP and COC can be used in combination with the cyclic olefin resin. In that case, different performances of COP and COC can be imparted to the film.

In the present invention, the cyclic olefin resin is preferably COC because of its dispersibility in polyethylene. The COC is preferably an ethylene / cyclic olefin copolymer in which the linear monomer is ethylene. Furthermore, the cyclic monomer is preferably norbornene or the like.

Further, in the present invention, the ethylene / cyclic olefin copolymer preferably has an ethylene / cyclic olefin content ratio of 15 to 40/85 to 60 by weight. More preferably, it is 30 to 40/70 to 60. If ethylene is less than 15% by weight, the rigidity becomes too high, which may deteriorate inflation moldability and bag making suitability, which is not preferable. On the other hand, when ethylene is 40% by weight or more, sufficient tearability and rigidity may not be obtained, which is not preferable. When the content ratio is in this range, the rigidity, easy tearability, processing stability, and impact strength of the film are improved, which is preferable.
Furthermore, the ethylene / cyclic olefin copolymer preferably has a glass transition point of 60 ° C. or higher. More preferably, it is 70 ° C. or higher. If the glass transition point is below the above range due to factors such as the content of the cyclic olefin being below the above range, for example, the barrier property of the aromatic component is lowered, sufficient rigidity cannot be obtained, and the high-speed packaging machine There is a risk of inferior suitability. On the other hand, if the glass transition point becomes too high due to factors such as the content of the cyclic olefin exceeding the above range, the melt moldability of the copolymer and the adhesiveness with the olefin resin may decrease, which is not preferable.
The weight average molecular weight of the cyclic olefin resin is preferably 5,000 to 500,000, more preferably 7,000 to 300,000.

The cyclic olefin resin is preferably contained in an amount of 5 to 40% by weight based on the entire anti-slip multilayer film. More preferably, it is 10 to 25% by weight. If it is less than 5% by weight, sufficient tearability cannot be obtained, which is not preferable. On the other hand, if it is more than 40% by weight, the rigidity becomes too high and the inflation moldability and bag making suitability are deteriorated, which is not preferable.

As a commercially available product that can be used as a cyclic olefin resin, examples of the ring-opening polymer (COP) of the norbornene-based monomer include "ZEONOR" manufactured by Nippon Zeon Co., Ltd., and the norbornene-based copolymer. Examples of (COC) include "Appel" manufactured by Mitsui Chemicals Co., Ltd. and "TOPAS" manufactured by Polyplastics Co., Ltd. In the present invention, TOPAS grade 8007 is preferable because the content ratio of the norbornene-based monomer is in the above range, processability, and the like.

(3) Inner layer The third layer, which is the inner layer when the anti-slip heavy-duty packaging film has a multi-layer structure, is not particularly limited as long as it is a resin that satisfies the physical characteristics for heavy-duty packaging. However, if the density difference between the outer layer and the inner layer is large, the film may be curled. Therefore, it is desirable that there is no or small density difference between the outer layer and the inner layer. Further, if the viscosity difference between the outer layer and the inner layer is large, it becomes difficult to obtain a film having a target thickness and layer ratio. Therefore, it is desirable that the resins of the outer layer and the inner layer have the same composition.

(4) High-pressure method low-density polyethylene In the present invention, when high-pressure method low-density polyethylene (hereinafter, also referred to as “LDPE”) is added to each layer, film molding can be stably performed. The high-pressure low-density polyethylene that can be used in the present invention is homopolyethylene, which is radically polymerized by an organic peroxide. The LDPE preferably has a melt flow rate at 190 ° C. in the range of 0.1 g / 10 minutes to 5 g / 10 minutes, but more preferably 0.1 2 g / 10 minutes in the present invention. If high-pressure low-density polyethylene having a melt flow rate of less than 0.1 g / 10 minutes is used for each layer, holes are likely to occur during film molding, and a film having a good appearance may not be obtained. On the other hand, if the melt flow rate exceeds 5 g / 10 minutes, the impact resistance, mechanical strength, etc. of the heavy-weight packaging film may decrease.
In the present invention, the melt flow rate is a value measured in accordance with JIS K 7210.

The density of the high-pressure low-density polyethylene ^{is preferably in the range of 0.915 to 0.935 g / cm 3} , but more preferably 0.920 to 0.930 g / cm ³ in the present invention. If high-pressure low-density polyethylene having a density of less than 0.915 g / cm ³ is used for each layer, holes are likely to occur during film molding, and a film having a good appearance may not be obtained. On the other hand, if the density ^{exceeds 0.935 g / cm 3} , the heat sealability may deteriorate. In the present invention, the density is a value measured based on JIS K 6922-2.
The content of the high-pressure low-density polyethylene constituting each layer is preferably in the range of 1 to 20% by weight, more preferably 1 to 15% by weight.

(5) Ethylene / α-olefin copolymer In the present invention, when an ethylene / α-olefin copolymer (hereinafter, also referred to as “LLDPE”) is used as a resin component of each layer, the physical properties of a heavy-duty package are improved. It can be met at a higher level. The ethylene / α-olefin copolymer may be a copolymer of ethylene and α-olefin and polymerized by a metallocene catalyst, a Ziegler catalyst, a Phillips catalyst, or the like, but melt at 190 ° C. The flow rate needs to be 0.1 g / 10 min to 3 g / 10 min. More preferably, the melt flow rate of the ethylene / α-olefin copolymer at 190 ° C. is 0.1 to 2.5 g / 10 minutes, and more preferably, the ethylene / α-olefin copolymer It is desirable that the melt flow rate at 190 ° C. is 0.1 to 2.0 g / 10 minutes. If the melt flow rate of the ethylene / α-olefin copolymer at 190 ° C. is too low, the molding processability is poor, while if the melt flow rate is too high, the impact resistance, mechanical strength and the like may be lowered.
In the present invention, the melt flow rate is a value measured in accordance with JIS K 7210.

The density of the ethylene / α-olefin copolymer is preferably ^{0.9000 to 0.940 g / cm 3.} It is preferably 0.9000 to 0.935 g / cm ³ . If the density is ^{less than 0.900 g / cm 3} , the rigidity is low and the suitability of the automatic bag making machine may deteriorate. Further, if the density of the polyethylene resin composition is ^{higher than 0.940 g / cm 3} , the strength of the film is lowered, which is not preferable.
In the present invention, the density is a value measured based on JIS K 6922-2.

Specifically, the ethylene / α-olefin copolymer used in the present invention is as follows. That is, the α-olefin that copolymerizes with ethylene is copolymerized in an amount of 0.1 to 15 mol%, preferably 0.5 to 10 mol%, particularly preferably 0.5 to 5 mol%. Yes, the type of α-olefin is usually an α-olefin having 3 to 8 carbon atoms, and specifically, propylene, butene-1, penten-1, hexene-1, heptene-1, octene-1, 4-Methylpentene-1 can be mentioned.
In the present invention, as the ethylene / α-olefin used for each layer, ethylene / α-olefin copolymer (C6-LLDPE), which is a copolymer of ethylene and 1-hexene, ethylene and so-called HAO (higher / α-olefin). ), Which is a copolymer of C6 or higher α-olefin such as 1-hexene or 1-octene, can be used by using an ethylene / α-olefin copolymer (HAO-LLDPE) to add a cyclic olefin copolymer. This is preferable for the purpose of preventing a decrease in impact resistance due to the above.
Further, as the ethylene / α-olefin used for each layer, two or more kinds of ethylene / α-olefin copolymers having different densities or MFRs are used for the purpose of preventing the impact resistance from being lowered due to the addition of the cyclic olefin copolymer. preferable.
The content of the ethylene / α-olefin copolymer constituting each layer (the total amount when two or more kinds of ethylene / α-olefin copolymers are used) is preferably 20 to 20 in the resin composition constituting the layer. It is in the range of 89% by weight, more preferably 25 to 85% by weight.

One of the features of the present invention is that the resin composition constituting the outer surface layer (first layer) has a slipperiness of 22 ° or more and 60 ° or less depending on the inclination angle measured by the following measurement method. do. Since the outer surface layer has low slipperiness, it is possible to prevent the load from collapsing when stacked. Here, in the present invention, the "slipperiness" is an index showing the slipperiness of the material, and is represented by the inclination angle (°) in the measurement of the coefficient of static friction. The larger the inclination angle (°) from the horizontal plane when the film, especially the anti-slip layer starts to slip, the higher the slipperiness.

In the present invention, the first layer, the second layer and the third layer have an antifogging agent, an antistatic agent, a heat stabilizer, a nucleating agent, an antioxidant, a lubricant, an antiblocking agent, a mold release agent, and an ultraviolet absorbing agent. Ingredients such as agents and colorants can be added within a range that does not impair the object of the present invention. In particular, it is preferable to appropriately add an anti-blocking agent and an antistatic agent to the first layer and the third layer in order to impart processing suitability at the time of film molding and packaging suitability of the filling machine. As these additives, those known to those skilled in the art can be used without particular limitation as long as the effects of the present invention are not impaired.

2. Anti-slip multi-layer heavy-duty packaging film The easily tearable multi-layer heavy-duty packaging film of the present invention comprises a specific first layer / a specific second layer / a specific third layer as described above. be. FIG. 1 shows a schematic cross-sectional view of an example of an easily tearable multilayer heavy-duty packaging film of the present invention. 1 is the first layer, 2 is the second layer, and 3 is the third layer.
The thickness of the entire anti-slip heavy-weight packaging film is preferably 60 μm or more. More preferably, it is 60 μm to 200 μm. When the thickness of the multilayer film is 60 μm or more, excellent impact resistance and drop strength can be exhibited in the film.

The thickness of the second layer in the anti-slip multi-layered heavy-duty packaging film of the present invention is preferably 20 to 70% with respect to the entire anti-slip multi-layered heavy-duty packaging film. More preferably, it is 20 to 50%. That is, the outer layer / intermediate layer / inner layer can have a thickness of about 1: 0.5: 1 to about 1: 4: 1. If the intermediate layer is thinner than 20%, sufficient tearability cannot be obtained, which is not preferable. On the other hand, if it is thicker than 70%, the rigidity becomes too high and the inflation moldability and bag making suitability are deteriorated, which is not preferable. When the intermediate layer is in this range, it is preferable because it is excellent in tearability, is advantageous in terms of cost, and improves the transparency, tearability, and pinhole resistance of the easily tearable multilayer film.

The method for producing the anti-slip film of the present invention is not particularly limited, and for example, the high-pressure low-density polyethylene and ethylene / α-olefin copolymer used for the first layer, and the cyclic olefin resin used for the second layer. The high-pressure method low-density polyethylene and ethylene / α-olefin copolymer and the high-pressure method low-density polyethylene and ethylene / α-olefin copolymer used for the third layer are heated and melted by separate extruders and coextruded. Examples thereof include a coextrusion method in which the first layer / second layer / third layer are laminated in this order in a molten state by a method such as a multi-layer die method or a feed block method, and then formed into a film by an inflation method or the like. This coextrusion method is preferable because the thickness ratio of each layer can be adjusted relatively freely, and a multilayer film having excellent hygiene and excellent cost performance can be obtained.

3. 3. Packaging material Anti-slip The film for packaging heavy objects of the present invention has anti-slip properties, is particularly excellent in impact resistance, has high rigidity, is excellent in sealing strength, and is excellent in suitability for automatic bag making machines, so it is particularly mass-produced. Suitable for packaging standard bags with fixed dimensions such as inner bags of paper bags and garbage bags, and anti-slip heavy-duty packaging bags that are hard to tear even when packaging heavy objects such as a large amount of fertilizer and grains, and do not easily slip off during stacking. Can be used for. For this purpose, the anti-slip heavy-duty packaging film of the present invention is preferably molded into a bag shape so that the first layer is an outer layer.

In the packaging material using the easily tearable film of the present invention, in order to weaken the initial tear strength and improve the opening property, any tear start portion such as V notch, I notch, perforation, microporous, etc. is formed in the seal portion. It is preferable to form.

Examples and comparative examples of the present invention are shown below.
1. 1. Physical property measurement method (1) Melt flow rate (MFR)
MFR was measured according to JIS K 7210.
(2) Measurement was performed at a density test temperature of 23 ° C. in accordance with JIS K 6922-2.

2. Film property evaluation method (1) Slipperiness measurement method Using a static friction coefficient measuring machine TYPE: 10 manufactured by Shinto Kagaku Co., Ltd. in an environment of room temperature of 23 ° C and humidity of 50%, the anti-slip layers are made to be contact surfaces. It was set and measured. The angle of inclination (°) from the horizontal plane when the anti-slip layer started to slip was used as the evaluation value of slipperiness.

3. 3. Molding of inflation film Inflation film was molded according to the following molding equipment and molding conditions.
Molding machine: 3-layer inflation film forming machine (manufactured by PLACO Co., Ltd.)
Extruder screw diameter: 50 mmφ x 2, 55 mmφ x 1
Die diameter: 200 mmφ
Extrusion amount: 64 kg / hr
Die lip gap: 3mm
Pick-up speed: 13m / min Blow-up ratio: 1.5
Molding resin temperature: 220 ° C
Film thickness: 130 μm
Cooling ring: Two-stage air cooling ring

4. Raw materials used (1) High-pressure method low-density polyethylene / LDPE: Made by Japan Polyethylene Corporation, trade name Novatec LD, MFR = 0.3 g / 10 minutes, density = 0.923 g / cm ³ (resin 1)
(2) Ethylene / α-olefin copolymer / ZN-C6LLDPE: Ethylene / α-olefin copolymer, polymerized under a Ziegler-Natta catalyst with ^{MFR = 0.5 g / 10 minutes and density = 0.922 g / cm 3.} Ethylene-hexene-1 copolymer (resin 2)
-LLDPE: Made by Japan Polyethylene Corporation, trade name kernel, MFR = 2g / 10 minutes, density = 0.907g / cm ³ (resin 3)
-LLDPE: Made by Japan Polyethylene Corporation, trade name kernel, MFR = 2g / 10 minutes, density = 0.880g / cm ³ (resin 4)
(3) Cyclic olefin resin / COC: Made by Polyplastics Co., Ltd., trade name TOPAS "8007", norbornene content 36 mol% (resin 5)

5. Examples and Comparative Examples Using the resins 1 to 4 described above, resins having the formulations shown in Table 1 (formulations 1 to 7) were obtained. Here, "blending 2" means that the resin of blending 1 was used in an amount of 75% by weight and the resin 3 was used in an amount of 25% by weight. Further, an inflation film having a thickness of 130 μm and a layer ratio of 1: 2: 1 was obtained by the formulation shown in Table 2. The evaluation results are shown in Table 2 below.

6. Evaluation Hereinafter, explanations of Examples and Comparative Examples of the present application will be described based on the data shown in Table 2.
In Comparative Example 1, it was shown that the first, second, and third layers were all composed of the resin of Formulation 1, the value of the inclination angle, which is an index showing the anti-slip property, was small, and the film surface was slippery.
On the other hand, in Example 1, both the first, second, and third layers are composed of the resin of Formulation 3, which is a resin having an anti-slip effect, and the value of the inclination angle, which is an index showing the anti-slip property, is a comparative example. It was shown that it was larger than 1 and the film surface was less slippery.
Examples 2 to 5 have a layer structure in which the first and third layers are compounded 2 to 5, which are resins having an anti-slip effect, and the second layer is compounded 1. It was shown that the film exhibits anti-slip properties when only the first and third layers on the surface are blended with a resin having anti-slip properties. It was also shown that, among the anti-slip resin formulations, the anti-slip property tends to increase as the amount of the resin ^{having a density of 0.860 to 0.910 g / cm 3 increased.}
Example 6 has a layer structure in which the first and third layers are compounded 6 which is a resin having an anti-slip effect, and the second layer is compounded 1. Compared with Example 2, the amount of the resin having a density of 0.860 to 0.910 g / cm ^{3 in} the anti-slip resin layer is the same, but the smaller the density, the larger the anti-slip property tends to be. It was shown to be in.
Example 7 has a layer structure in which the first and third layers are compounded 4 which is a resin having an anti-slip effect, and the second layer is compounded 7. Even if a resin containing COC is used for the intermediate layer of the second layer and the film is easily torn, if the first and third layers on the surface are blended with a resin having anti-slip properties, the anti-slip properties of the film are exhibited. The thing was shown.
In Example 8, the first layer is composed of the resin of compounding 3, and the second and third layers are layered using compounding 1. Since the resin composition is different on both surfaces of the film, there is concern about the possibility of curling of the film, but since one surface is a resin compound that has an anti-slip effect, it is shown that the film exhibits anti-slip properties. Was done.

The anti-slip heavy-duty packaging film containing the polyethylene-based resin composition of the present invention has not only the sealing strength, film waist, and impact strength required for the quality of a packaging bag for accommodating heavy objects such as rice bags and fertilizer bags. , It is possible to contribute to the prevention of slipping during stacking.
Therefore, the industrial value of the polyethylene-based resin composition of the present invention, which can economically provide a molded product having such desirable properties, is extremely large.

1: Outer layer (layer with anti-slip property)
2: Intermediate layer 3: Inner layer

Claims (6)

At least the outer surface layer is a polyethylene resin polymerized with a metallocene-based catalyst having a density of 0.860 to 0.910 g / cm ³ and a melt flow rate of 0.1 to 10 g / 10 minutes at 190 ° C., from 15 to 75. a resin component comprising by weight%, as a whole resin component of the outer surface layer, melt flow rate density in 0.911~0.940g / cm ^3, 190 ℃ is Ri Ah at 0.1-5 g / 10 min, An anti-slip film characterized by containing a norbornene-based copolymer (COC) in which a norbornene-based monomer and α-olefin are copolymerized at least in a layer adjacent to the outer surface layer. The antislip film according to claim 1, wherein the outer surface layers are brought into contact with each other and tilted, and the tilt angle at the time of starting to slide is 22 ° to 60 °. The anti-slip film according to any one of claims 1 or 2, wherein the film is a multilayer film. The anti-slip film according to any one of claims 1 to 3 , wherein the film is formed by inflation molding. The anti-slip film according to any one of claims 1 to 4 , which is used for heavy-weight packaging. The anti-slip film according to claim 5 , wherein the thickness of the film is 60 μm or more.

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