JP7552587B2 - Polyethylene resin film - Google Patents

Description

The present invention relates to a polyethylene resin film, and a laminate and packaging material using the same.

In recent years, packaging or containers using films have come to be used in a wide range of fields due to their convenience, resource conservation, and reduced environmental impact. Compared to conventional molded containers and products, films have the advantages of being lightweight, easy to dispose of, and low cost.

A sealant film is generally used by laminating it with a base film such as a biaxially oriented nylon film, a biaxially oriented ester film, or a biaxially oriented polypropylene film, which has inferior low-temperature heat adhesion to the sealant film. If the sealant film is stored in a roll after lamination with such a base film, blocking occurs between the sealant film and the base film, making it difficult to unwind the laminate film before bag making, or blocking occurs between the sealant films that become the inner surface of the bag during bag making, making it difficult to fill the food.
Therefore, a known method is to sprinkle powder such as starch on the surface of the sealant film to avoid the above-mentioned blocking between the sealant film and the substrate, and between sealant films themselves.
However, this method not only contaminates the area around the film processing equipment, but also causes problems such as significantly worsening the appearance of the packaged food, powder adhering to the sealant film being directly mixed into the package along with the food, and reducing the heat seal strength.

There have been reports of polyethylene resin films that use inorganic fine powders or particles such as silica in polyethylene resin.

However, this method has the problem that scratches are likely to occur when film surfaces containing inorganic fine powders or inorganic particles such as silica added to polyethylene resin films are rubbed against each other, and when the sealant fill or laminate with the base film passes through a laminating machine or bag making machine, the inorganic fine powder or inorganic particles are likely to fall off, causing scratches and foreign matter problems.

Furthermore, a polyethylene resin film using organic crosslinked particles made of a copolymer mainly composed of an acrylic monomer and a styrene monomer has been reported.
However, this method is still not sufficient, although its scratchability is not as bad as that of inorganic particles, and the problem of particles falling off still remains.

Furthermore, in order to improve the blocking resistance of polyethylene resin films, it has been reported that low-density polyethylene resin or high-density polyethylene resin is added to linear low-density polyethylene resin (see, for example, Patent Documents 1 and 2).

However, these methods have problems such as deterioration in mechanical strength properties such as tensile strength and transparency, and also poor blocking resistance.
Furthermore, a polyethylene resin film has been reported in which particles made of a high molecular weight polyethylene resin are added to a high density polyethylene resin.
However, this approach has the problem that it is inferior in mechanical strength properties such as tear strength, heat sealability at low temperatures, and transparency, and that the addition of particles made of polyethylene resin actually makes blocking resistance and slipperiness unstable.

Japanese Patent Application Publication No. 10-120849 Japanese Patent Application Publication No. 10-87909

The present invention aims to provide a polyethylene resin film that is excellent in appearance, heat sealability, stable blocking resistance, stable slipperiness, and also excellent in scratch resistance. It also aims to provide a laminate and further a package using this polyethylene resin film.

As a result of intensive research, the inventors have discovered that the above-mentioned problems can be solved by controlling the protrusion height and organic organic lubricant content on the surface of a layer made of a polyethylene resin composition containing a polyethylene resin having a density within a specific range and particles made of a polyethylene resin, thereby achieving the present invention.

That is, the present invention relates to a polyethylene-based resin film having at least one layer A made of a polyethylene-based resin composition, in which the polyethylene-based resin composition constituting the layer A satisfies the following 1) to 3), and at least one surface of the layer A satisfies both of the following 4) and 5).
1) The polyethylene resin has a density of 900 kg/m3 or ^more and 935 kg/m3 ^or less.
2) Contains particles made of polyethylene resin.
3) The content of the organic lubricant is 0.16% by weight or more.
4) The three-dimensional surface roughness SRa is 0.05 to 0.2 μm.
5) The maximum peak height SRmax is 2 to 15 μm.

Another embodiment is a polyethylene-based resin film having at least one layer A made of a polyethylene-based resin composition, in which the polyethylene-based resin composition constituting the layer A satisfies the following 1) to 3), and at least one surface of the layer A satisfies both of the following 4) and 5).
1) The density is 900 kg/m3 or ^more and 935 kg/m3 ^or less.
2) Contains particles made of polyethylene resin.
3) The content of the organic lubricant is 0.16% by weight or more.
4) The three-dimensional surface roughness SRa is 0.05 to 0.2 μm.
5) The maximum peak height SRmax is 2 to 15 μm.

3. The polyethylene resin multilayer film according to claim 1, wherein the particles made of the polyethylene resin have a resin hardness of D70 or less.
In this case, it is preferable that the particles made of the polyethylene resin have a viscosity average molecular weight of 1.5 million or more and a melting point peak temperature by DSC of 150° C. or less.

Furthermore, in this case, it is preferable that the average particle size of the particles made of the polyethylene resin is 5 to 15 μm.

Furthermore, in this case, it is preferable that the content of particles made of the polyethylene resin in the polyethylene resin composition constituting layer A is 0.2 to 2.0 weight %.

Furthermore, in this case, it is preferable that the blocking value between the surfaces of the A layers is 200 mN/70 mm or less.

Furthermore, in this case, it is preferable that the A layer surfaces are set together in a Gakushin abrasion tester manufactured by Yasuda Seiki and the change in haze after 100 abrasions with a load of 200 g is 5% or less.

Furthermore, in this case, a laminate comprising any of the polyethylene resin films described above and a substrate film made of the composition is preferred.

Furthermore, in this case, a packaging bag containing the laminate is preferred.

The present invention can provide a polyethylene resin film that is excellent in appearance, heat sealability, stable blocking resistance, and stable slipperiness, and is particularly excellent in scratch resistance. It can also provide a laminate and a package using this polyethylene resin film.

(Layer A made of polyethylene resin composition)
The layer A in the present invention is made of a polyethylene resin composition, which mainly contains a polyethylene resin and also contains particles made of a polyethylene resin. The polyethylene resin composition preferably contains 50% by weight or more of a polyethylene resin, more preferably 70% by weight or more, and even more preferably 90% by weight or more.
(Polyethylene resin)
The polyethylene resin in the present invention is any one of a homopolymer of an ethylene monomer, a copolymer of an ethylene monomer and an α-olefin, and a mixture thereof. Examples of the α-olefin include propylene, butene-1, hexene-1, 4-methylpentene-1, octene-1, and decene-1.

The density range of the polyethylene resin is more preferably 900 to 935 kg/m ³ , further preferably 910 to 933 kg/m ³ , and particularly preferably 910 to 930 kg/m ^3. Polyethylene resins having a density of 935 kg/m ³ or less do not have a high heat seal initiation temperature, are easy to process into bags, and are excellent in transparency.
More importantly, the inventors have found that when a polyethylene resin having a density of 935 kg/m3 ^{or less} is used, the particles made of polyethylene resin make it easy to make the three-dimensional surface roughness SRa of at least one surface of layer A 0.05 μm or more and the maximum peak height SRmax 2 μm or more, and the polyethylene resin film is easy to obtain slipperiness, blocking resistance, and scratch resistance, so that wrinkles and lumps are unlikely to occur during coating, printing, and bag making, and transparency is also easily maintained. In particular, the blocking resistance is stable and does not easily vary between the measured values measured four times.
Furthermore, when a polyethylene resin having a density of 900 kg/m3 ^or more is used, the particles made of polyethylene resin make it easy to control the three-dimensional surface roughness SRa of at least one surface of layer A to 0.2 μm or less and the maximum peak height SRmax to 15 μm or less, and it is easy to improve the transparency and stiffness.

Blocking resistance is measured by overlapping the A-layer surfaces of the film on each other and subjecting the sample to a heat press (model: SA-303, manufactured by Tester Sangyo Co., Ltd.) with a size of 7 cm x 7 cm, a temperature of 50°C, a pressure of 18 MPa, and a time of 15 minutes. The sample blocked by this pressure treatment and a bar (diameter 6 mm, material: aluminum) are attached to an autograph (model: UA-3122, manufactured by Shimadzu Corporation) so that the bar and the peeling surface are horizontal, and the force at which the bar peels the blocked part at a speed (200 m/min) is measured four times, and the average value is used as an index. When a polyethylene-based resin with a density of 935 kg/m3 or ^less is used, not only is there little variation in the measured values of the four measurements, but there is also a tendency for the heat seal initiation temperature to be less likely to increase. It is preferable that the variation in the measured values of the four measurements is at the same level as when inorganic particles are used.
The reason why the measured values are unlikely to vary from sample to sample is presumably that when particles made of polyethylene with a density of 935 kg/m3 ^or less and polyethylene-based resin are melt-mixed, changes in particle size are unlikely to occur due to a decrease in the viscosity average molecular weight of the particles made of polyethylene-based resin or entanglement of molecular chains with polyethylene-based resin other than the particles made of polyethylene-based resin, and as a result, the protrusions formed on the surface are uniform.

Scratch resistance was determined by placing the A-layer surfaces of polyethylene resin films together in a Yasuda Seiki Gakushin abrasion tester and judging the change in haze after 100 abrasions with a load of 200 g. The haze was measured at the center of the film (width x length = 50 mm x 180 mm) before it was placed on the abrasion table (a point was placed at the edge, and points were placed at both ends that did not affect the haze measurement from the side opposite the abraded surface), and then measuring the haze at the same position after abrasion to determine the difference.

From the viewpoint of film-forming properties, etc., it is preferable that the polyethylene resin has a melt flow rate (hereinafter sometimes referred to as MFR) of about 2.5 to 4.5 g/min. Here, MFR is measured in accordance with ASTM D1893-67. The polyethylene resin is synthesized by a method known per se.

When using polyethylene resins with a low MFR of 2.5 g/10 min or less, as explained in the density section, the particle size tends to change due to a decrease in the viscosity average molecular weight of the particles made of polyethylene resin and entanglement of molecular chains with polyethylene resins other than the particles made of polyethylene resin, so care must be taken with the extrusion conditions. When producing films at high speed using a large film-making machine, an MFR of around 3 to 4 g/10 min is particularly preferable for film-forming properties.

For polyethylene-based resins, from the standpoint of heat resistance, etc., the melting point is preferably 85°C or higher, more preferably 100°C or higher, and particularly preferably 110°C or higher.

The polyethylene resin may be a single system, but two or more polyethylene resins with different densities within the above density range can also be blended. When two or more polyethylene resins with different densities are blended, the average density and blending ratio can be estimated by GPC measurement or density measurement.

As the above-mentioned polyethylene resin having a density of 900 to 935 kg/ ^m3, the following can be selected according to the application: high-pressure low-density polyethylene (LDPE), which is transparent, highly flexible, and has excellent average tear strength and tensile strength; linear short-chain branched polyethylene (LLDPE), which is copolymerized with a small amount of butene-1/hexene-1/octene-1 and has many short molecular chains in the molecular chain, and has excellent sealing performance and physical strength; and metallocene-catalyzed linear short-chain branched polyethylene (LLDPE), which shows a very sharp molecular weight distribution, has a uniform distribution of comonomers, and has excellent tear, tensile, and puncture strengths and pinhole resistance.
As the polyethylene resin used in the sealing layer, commercially available products may be used, for example, Umerit (registered trademark) 2040FC, 0540F, 3540FC manufactured by Ube Maruzen Polyethylene Co., Ltd., and Sumikathene (registered trademark) E FV402, E FV405 manufactured by Sumitomo Chemical Co., Ltd.

(Particles made of polyethylene resin)
The particles made of the polyethylene resin contained in the polyethylene resin composition constituting the A layer preferably have a viscosity average molecular weight of 1.5 million or more, more preferably 1.6 million or more, and even more preferably 1.7 million or more, and preferably 2.5 million or less, more preferably 2.4 million or less, and even more preferably 2.3 million or less.
When the viscosity average molecular weight of the particles made of polyethylene-based resin is within this range, it becomes possible to control the average particle size of the particles made of polyethylene-based resin, and by using it in combination with a polyethylene-based resin of a specific density, it is possible to set the three-dimensional surface roughness SRa of at least one surface of layer A to 0.05 to 0.2 μm and the maximum peak height SRmax to 2 to 15 μm.
The reason for this is believed to be that the difference in molecular weight between the particles made of polyethylene-based resin and polyethylene-based resin other than the particles made of polyethylene-based resin is very large, so the molecules do not mix sufficiently, and even in the film obtained by melt mixing and extrusion, the particles made of polyethylene-based resin easily maintain a shape close to spherical, and aggregation due to fusion or adhesion between particles is unlikely to occur, making it possible to form protrusions with controlled shapes on the film surface.
When the viscosity average molecular weight of the particles made of polyethylene resin is 1,500,000 or more, and the temperature during melt mixing with a polyethylene resin other than the particles made of polyethylene resin is higher than the melting point peak of the particles made of polyethylene resin, even under film production conditions of high shear or high draft ratio using a large extruder, decomposition due to heat or shear, fusion and aggregation of the particles made of polyethylene resin, and changes in particle size and shape of the particles made of polyethylene resin due to partial compatibility with polyethylene resins other than the particles made of polyethylene resin are unlikely to occur, so that protrusions with a controlled shape like inorganic particles or organic crosslinked resin particles can be easily formed, and not only does the function as an antiblocking agent become sufficient, but also the appearance such as transparency, the mechanical strength of the film, or the heat sealability are unlikely to be affected.
Furthermore, and this is also surprising, it has been found that particles made of polyethylene resin having a viscosity average molecular weight of 1.5 million or more have the property of being unlikely to aggregate in polyethylene resin, yet are unlikely to fall off from the polyethylene resin near the film surface, a characteristic not possessed by inorganic particles or organic crosslinked resin particles.
When the viscosity average molecular weight is 1.5 million to 2.5 million, it becomes easy to set the average particle size to 5 to 20 μm, and when the sealing layer raw material is melt-mixed and extruded to form a film, it tends to be easy to form suitable film surface protrusions.
Furthermore, when the viscosity average molecular weight of the particles made of polyethylene resin is 1.5 million or more, the particles themselves have lubricating properties, which contributes to improving blocking resistance and slippage, and since the particles made of polyethylene resin are soft, it is believed that scratch resistance is also improved.

The resin hardness of the particles made of polyethylene resin is preferably D70 or less. When the hardness is 70 or less, defects are less likely to occur in the laminated layers of the film, for example, the vapor deposition layer, and the barrier properties are less likely to decrease. The hardness is more preferably D68 or less.
Furthermore, when the hardness of the particles made of polyethylene resin is D60 or more, the slipperiness is improved and is less likely to deteriorate even when subjected to heat during film processing.

Particles made of polyethylene-based resins are homopolymers of ethylene monomers, or copolymers of ethylene monomers and α-olefins, as well as mixtures of these. Examples of α-olefins include propylene, butene-1, hexene-1, 4-methylpentene-1, octene-1, decene-1, etc.

The density range of the particles made of polyethylene resin is preferably 930 to 950 kg/m ³ , more preferably 935 to 945 kg/m ³ , and even more preferably 937 to 942 kg/m ^3. Particles made of polyethylene resin with a density of less than 930 kg/m ³ are soft and difficult to maintain the shape of the particles during melt extrusion, so that blocking resistance is likely to decrease. Meanwhile, particles made of polyethylene resin with a density of more than 950 kg/m ³ are hard and not only easily deteriorate in scratch resistance but also have a decreased affinity with the base polyethylene resin, so that there is a possibility that the resistance to falling off is decreased.

The average particle size of the particles made of the polyethylene resin contained in the polyethylene resin composition constituting the layer A is preferably 5 μm or more, more preferably 6 μm or more, and even more preferably 7 μm or more. The average particle size is preferably 20 μm or less, more preferably 17 μm or less, and particularly preferably 15 μm or less.
In addition, it is preferable that the film does not contain particles having a particle size of 30 μm or more. Even if the average particle size is 20 μm or less, if the film contains a certain amount of 10% or more particles having a particle size of 30 μm or more, the maximum peak height of the film surface is likely to exceed 15 μm, and if this occurs, the flickering described below will occur when the film surface is visually observed.
Furthermore, particles larger than 30 μm are also undesirable in that they have the same appearance as gel defects and result in a decrease in quality.

By making the average particle size of the particles made of polyethylene resin 5 μm or more, it is possible to improve the slipperiness and blocking resistance.
Furthermore, when the average particle size is 20 μm or less, the three-dimensional surface roughness SRa and maximum protrusion height SRmax of at least one surface of layer A do not become too large, and the number of protrusions increases compared to when the same weight of particles made of polyethylene resin is added, making it easier to obtain sufficient slip properties, blocking resistance, and scratch resistance for film processing.

Furthermore, the average particle size of particles made of polyethylene resin is less likely to change due to crushing or agglomeration caused by kneading during extrusion than relatively soft inorganic particles such as talc or calcium carbonate, making it easier to control the average particle size (before and after extrusion). By setting the average particle size of particles made of polyethylene resin in the range of 5 to 20 μm, protrusions caused by coarse particles are almost eliminated, and since the hardness of the protrusions themselves is lower than that of inorganic particles, adverse effects on the other side of layer A or on coatings provided in layers other than layer A are suppressed.

The content of the particles made of polyethylene resin in the polyethylene resin composition constituting the A layer is preferably 0.2% by weight or more, more preferably 0.3% by weight or more, and even more preferably 0.4% by weight or more, based on the polyethylene resin composition. Also, it is preferably 2.0% by weight or less, more preferably 1.5% by weight or less, and even more preferably 1.0% by weight or less. When the amount of the particles made of polyethylene resin added is 0.2% by weight or more, it becomes easy to make the maximum peak height of at least one of the A layer surfaces 2 μm or more per specified area (0.2 mm ² ), and it becomes easy to obtain blocking resistance and slipperiness. Also, when the amount of the particles made of polyethylene resin added is 2.0% by weight or less, the projections on the A layer surface do not become too many, and transparency and low-temperature sealability are also easily improved.

The polyethylene resin composition constituting the A layer contains an organic lubricant. The film has improved slipperiness and anti-blocking effect, and the film is easy to handle. The reason for this is that the organic lubricant bleeds out and is present on the film surface, thereby exerting a lubricant effect and a mold release effect. Furthermore, it is preferable to add an organic lubricant having a melting point above room temperature.
Examples of organic lubricants include fatty acid amides and fatty acid esters. Specific examples include oleic acid amide, erucic acid amide, behenic acid amide, ethylene bisoleic acid amide, hexamethylene bisoleic acid amide, ethylene bisstearic acid amide, etc. These may be used alone, but it is preferable to use two or more of them in combination, since this makes it possible to maintain lubricity and anti-blocking effects even under harsh environments.

The lower limit of the content of the organic lubricant in the polyethylene resin composition constituting layer A is preferably 0.16% by weight or more, preferably 0.18% by weight, more preferably 0.19% by weight, and particularly preferably 0.21% by weight. If it is 0.16% by weight or more, the slipperiness tends to be stable immediately after film formation. The upper limit is preferably 0.3% by weight, more preferably 0.25% by weight. If it is 0.3% by weight or less, it is not too slippery and is less likely to whiten over time.

When inorganic particles are contained in layer A, the average particle size is preferably sufficiently smaller than the average particle size of the particles made of polyethylene resin. Preferably, the average particle size of the inorganic particles is 50% or less of the average particle size of the particles made of polyethylene resin, and preferably does not contain coarse particles having a particle size of twice or more the average particle size.
In the polyethylene resin composition constituting layer A, the content of inorganic particles is preferably 0.20% by weight or less, more preferably 0.10% by weight or less, even more preferably 0.05% by weight or less, and most preferably 0% by weight. By making the content of inorganic particles 0.20% by weight or less, not only is the residue at the time of incineration reduced, but it is also easy to obtain effects similar to those obtained when only particles made of polyethylene resin are added, such as scratch resistance and particles not falling off.

Even when inorganic particles are added, if the particle size is as described above and the residue upon incineration of the film is 500 ppm or less, the incineration residue can be made extremely small when the film is incinerated compared to films containing conventional inorganic particles.
The inorganic particles referred to here are inorganic substances generally used as antiblocking agents, such as silica, talc, calcium carbonate, diatomaceous earth, and zeolite.

When crosslinked organic particles are contained in layer A, the average particle size is preferably sufficiently smaller than the average particle size of the particles made of polyethylene resin. Preferably, the average particle size of the crosslinked organic particles is 50% or less of the average particle size of the particles made of polyethylene resin, and the crosslinked organic particles contain almost no coarse particles having a particle size of more than twice the average particle size.
The content of crosslinked organic particles in the polyethylene resin composition constituting layer A is preferably equal to or less than the amount of particles made of polyethylene resin from the viewpoints of suppressing die resin buildup and cost.
In the polyethylene resin composition constituting layer A, in order to obtain the maximum effect of adding particles made of polyethylene resin, such as scratch resistance and prevention of particle shedding, as in the case of inorganic particles, it is most preferable that the polyethylene resin composition does not contain crosslinked organic particles.
The crosslinked organic particles referred to here are organic crosslinked particles typified by polymethyl acrylate resins and the like.

(Polyethylene Resin Composition)
The density range of the polyethylene resin composition constituting the A layer is preferably 900 to 935 kg/m ³ , more preferably 910 to 933 kg/m ³ , still more preferably 910 to 930 kg/m ³ , particularly preferably 915 to 928 kg/m ³ , and particularly preferably 915 to 925 kg/m ^3. Polyethylene resins with a density of less than 900 kg/m ³ tend to have reduced blocking resistance.
A polyethylene resin composition having a density of 935 kg/m3 or ^less has a low heat seal initiation temperature, is easy to process into bags, and has excellent transparency. More importantly, the inventors have found that when a polyethylene resin having a density of 940 kg/m3 or ^less is used, the polyethylene resin multilayer film is likely to have stable blocking resistance or stable slippage, and is extremely excellent in scratch resistance due to the synergistic effect of the organic organic lubricant contained in the polyethylene resin composition constituting the A layer and the surface protrusions made of polyethylene resin particles.

For polyethylene resin compositions, from the viewpoint of film-forming properties, etc., the melt flow rate (hereinafter sometimes referred to as MFR) is preferably about 2.5 to 4.5 g/min. Here, MFR was measured in accordance with ASTM D1893-67.

(Multi-layer structure)
The polyethylene resin film of the present invention may have a multi-layer structure. In the case of a multi-layer structure, in addition to the layer A, one or more other layers may be provided.
As a specific method for forming a multi-layer structure in this way, a general multi-layering device (such as a multi-layer feed block, a static mixer, or a multi-layer multi-manifold) can be used.
For example, a method can be used in which thermoplastic resins discharged from different flow paths using two or more extruders are laminated in multiple layers using a field block, a static mixer, a multi-manifold die, etc. It is also possible to use only one extruder and introduce the above-mentioned multi-layering device into the melt line from the extruder to the T-die.

In the case of a three-layer structure, it is recommended that the other layers be an intermediate layer (layer B) and a laminate layer (layer C), in that order. In this case, the outermost layers are layers A and C, respectively.

The polyethylene resin used in the intermediate layer (B layer) and laminate layer (C layer) may be, for example, one or a mixture of two or more selected from ethylene-α-olefin copolymers and high-pressure polyethylene. The ethylene-α-olefin copolymer is a copolymer of ethylene and an α-olefin having 4 to 18 carbon atoms, and examples of the α-olefin include butene-1, hexene-1, 4-methylpentene-1, octene-1, and decene-1.
Films obtained from these polyethylene resins have excellent heat seal strength, hot tack properties, impurity sealability, and impact resistance. The polyethylene resins may be mixed with other resins, such as ethylene-vinyl acetate copolymers and ethylene-acrylic acid ester copolymers, to the extent that these properties are not impaired.

In this case, the polyethylene resins used in the intermediate layer (layer B) and the laminate layer (layer C) may be the same or different. Also, particles made of polyethylene resin may be added, but it is not necessary to add them. However, it is preferable not to add them because the presence of large particles such as coarse particles in the laminate layer can easily cause lamination lifting.

In this case, it is preferable that the average density of the polyethylene resin composition constituting each layer of the film is A layer <= intermediate layer (B layer) <= laminate layer (C layer). The organic organic lubricant contained therein does not easily migrate to layers with higher density, so it is effective in maintaining the slipperiness of A layer after lamination and in maintaining the laminate strength over time.

In this case, the lower limit of the density of the polyethylene resin composition constituting the intermediate layer (B layer) is preferably 900 kg/m ³ , more preferably 920 kg/m ³ , and even more preferably 930 kg/m ^3. If it is less than the above, the stiffness may be weak and processing may be difficult.
The upper limit of the density of the intermediate layer (B layer) is preferably 960 kg/m ³ , more preferably 940 kg/m ³ , and further preferably 935 kg/m ³ .

The polyethylene resin composition constituting the intermediate layer (B layer) of the polyethylene resin film of the present invention may contain the above-mentioned organic organic lubricant, and the lower limit of the organic organic lubricant is preferably 100 ppm. If the amount is less than the above, the slipperiness may be deteriorated.
The upper limit of the organic lubricant in the polyethylene resin composition constituting the intermediate layer is preferably 2000 ppm, more preferably 1500 ppm. If the upper limit is exceeded, the lubricant becomes too slippery, which may cause misalignment during winding or whitening over time.

Recycled resin may be blended into the middle layer (layer B) of the film of the present invention to an extent that does not impair its quality.

In the present invention, it is preferable to subject the laminate layer (layer C) surface of the polyethylene resin film described above to actinic radiation treatment such as corona treatment. This improves the laminate strength.

When the polyethylene resin film of the present invention is two-layered, it is preferable that layer A be a sealing layer and the other layer be a laminate layer (layer C).

(Three-dimensional surface roughness SRa)
The three-dimensional surface roughness SRa of the seal layer of the polyethylene-based resin multilayer film of the present invention is preferably 0.05 μm or more. When SRa is 0.05 μm or more, the film has excellent slip properties and anti-blocking properties. SRa is more preferably 0.07 μm or more, and particularly preferably 0.1 μm or more.
The three-dimensional surface roughness SRa of the seal layer of the polyethylene-based resin multilayer film of the present invention is preferably 0.2 μm or less. When SRa is 0.2 μm or less, transparency is less likely to decrease. SRa is more preferably 0.18 μm or less, and particularly preferably 0.16 μm or less. The measurement method is the method described in the examples.
(Maximum protrusion height SRmax)
The maximum projection height of at least one surface of the A layer of the polyethylene resin film of the present invention must be 2 μm or more and 15 μm or less. If the maximum projection height SRmax exceeds 15 μm, it is not preferable because it causes a defective appearance. The measurement method is the method described in the examples.

(Heat seal starting temperature)
The upper limit of the heat seal initiation temperature of the polyethylene resin film of the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film is preferably 140° C., more preferably 130° C. If the temperature exceeds the above range, sealing processing may become difficult.

(Achieved heat seal strength)
The lower limit of the heat seal strength attained by the polyethylene resin film of the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film at 150° C. is preferably 30 N/15 mm, more preferably 35 N/15 mm. If it is less than the above, the bag may be easily torn after bag formation.
The upper limit of the heat seal strength at 150°C of the polyethylene resin film of the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film is preferably almost the same as the breaking strength of the laminated nylon. When it is the same as the breaking strength of the nylon, it means that the lamination strength is sufficiently high and the peel strength of the seal interface is sufficiently high. The measurement method is the method described in the examples.

(Blocking Strength)
The blocking strength of the polyethylene resin film in the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film is preferably as small as possible, more preferably 200 mN/70 mm or less, and even more preferably 150 mN/70 mm. If it exceeds the above range, the powder-free property and the opening property of the bagged product cannot be sufficiently obtained. The measurement method is the method described in the Examples.

(Coefficient of Friction)
The lower limit of the static friction coefficient of the polyethylene resin film in the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film is preferably 0.05, more preferably 0.08. If it is less than the above, the film may slip too much during winding, which may cause winding misalignment.
The upper limit of the static friction coefficient after lamination is preferably 0.70, more preferably 0.5. If it exceeds the above range, the opening property after bag making and the filling property of the contents are poor, and loss during processing may increase.
The measurement is carried out according to the method described in the Examples.

(Hayes)
The lower limit of the haze of the polyethylene resin film of the present invention is preferably 3%, more preferably 4%, and further preferably 5%. If it is less than the above, the antiblocking agent may not be sufficiently present on the surface, which may cause blocking.
The upper limit of the haze is preferably 18%, more preferably 16%, and even more preferably 13%. If the haze exceeds the above range, it may be difficult to visually confirm the contents. The measurement method is the method described in the examples.

(Flickering)
It is preferable that the polyethylene resin film of the present invention exhibits almost no flickering or exhibits fine flickering that is uniform and not particularly bothersome. The measurement method is the method described in the Examples.
Conventional non-powder types, which have blocking resistance without sprinkling powder such as starch on the film surface, have included inorganic particles with an average particle size of about 10 μm, but these often contain coarse particles and are prone to flickering and poor transparency.

(Scratch resistance)
In the laminate obtained by laminating a biaxially oriented nylon film (15 μm) and a polyethylene resin film, even after the polyethylene resin film surfaces are rubbed together, the change in haze is preferably 3% or less, more preferably 2% or less, even more preferably 1% or less, and particularly preferably 0.5% or less. The measurement method is the method described in the Examples.
Conventional non-powder types, which have blocking resistance without sprinkling powder such as starch on the film surface, have included inorganic particles with an average particle size of about 10 μm. However, because inorganic particles are much harder than polyethylene resin, scratch resistance tends to be poor even when a sufficient amount of organic organic lubricant is present on the film surface.

(Young's Modulus)
The lower limit of the Young's modulus (MD) of the polyethylene resin film of the present invention is preferably 60 MPa, more preferably 70 MPa. If it is less than the above, the stiffness may be too weak and processing may be difficult. The upper limit of the Young's modulus (MD) is preferably 600 MPa, more preferably 500 MPa.

The lower limit of the Young's modulus (TD) of the polyethylene resin film of the present invention is preferably 60 MPa, more preferably 70 MPa. If it is less than the above, the film may be too weak and difficult to process. The upper limit of the Young's modulus (TD) is preferably 600 MPa, more preferably 500 MPa.

(Laminate)
The polyethylene resin multi-layer film of the present invention can also be used as a packaging film or a packaging sheet in a laminate configuration in which at least one other base film is further laminated.
The base film is not particularly limited, and examples of the base film include polyolefin films such as polyethylene and polypropylene, styrene resin films, polyester films such as polyethylene terephthalate and polybutylene terephthalate, polyamide films such as nylon 6 and nylon 6,6, or stretched films thereof, laminated films of polyolefin films and resin films having gas barrier properties such as polyamide films or ethylene-vinyl alcohol copolymer films, and, if necessary, metal foils such as aluminum, or vapor-deposited films or papers on which aluminum, silica, etc. are vapor-deposited, and are appropriately selected and used depending on the intended use of the laminate. The base film may be used not only as a single type, but also as a combination of two or more types laminated together.

In this case, it is preferable to have a base film adjacent to the laminate layer side of the polyethylene resin multilayer film.

As a method for laminating the polyethylene-based resin multilayer film onto the above-mentioned substrate film, a method of dry lamination of the substrate film and the polyethylene-based resin multilayer film can be adopted. In that case, the structure can be polyethylene-based resin multilayer film/adhesive layer/other substrate film. For the adhesive layer, an anchor coating agent such as a urethane-based or isocyanate-based adhesive can be used, or a modified polyolefin such as an unsaturated carboxylic acid grafted polyolefin can be used as an adhesive resin to firmly bond adjacent layers.

There are no particular restrictions on the thickness of the laminate, but if the laminate is used as a film for a lid or the like, it is preferably 10 to 200 μm, and if it is used as a sheet for cups or trays, it is preferably 200 to 1000 μm.

(Package)
A container can be manufactured by placing the seal layer surfaces of the sealant films of the laminate facing each other, or placing the seal layer surface of the sealant film layer of the laminate facing another base film, and then heat sealing at least a part of the periphery from the laminate side to form a desired container shape. Also, a sealed bag-like container can be manufactured by heat sealing the entire periphery. If the molding process of this bag-like container is combined with a filling process of the contents, that is, the bottom and sides of the bag-like container are heat sealed, then the contents are filled, and then the top is heat sealed, a package can be manufactured. Therefore, this laminate can be used in an automatic packaging device for solid, powder, or liquid materials such as snacks.

A container with the contents packaged therein can also be obtained by filling a container formed into a cup shape by vacuum forming or pressure forming, a container obtained by injection molding or blow molding, or a container formed from a paper base material with the contents, and then covering it with the laminate of the present invention as a lid material and heat sealing it.

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not particularly limited by the following examples. The measured values of each item in the detailed description of the present invention and the examples were measured by the following methods.

Hereinafter, an embodiment of the present invention will be described in detail.
(1) Measurement Method for Particles Made of Polyethylene Resin For the particles made of polyethylene resin, each physical property of the raw material resin before processing was measured.
It is also possible to separate and measure the particles made of the polyethylene resin even after film formation by completely dissolving the particles in decane and then isolating the high molecular weight portion using GPC or the like.

(2) Viscosity average molecular weight of particles made of polyethylene resin: Measured in accordance with ASTM-D4020.

(3) Average particle size of particles made of polyethylene resin
The average particle size of the particles made of polyethylene resin before use was measured as follows.
The particles were dispersed in ion-exchanged water stirred at a prescribed rotation speed (about 5000 rpm) using a high-speed stirrer, and the resulting dispersion was added to isotone (physiological saline) and further dispersed using an ultrasonic disperser. The particle size distribution was then determined by the Cole counter method, and the average particle size was calculated.

(4) Particle size distribution of polyethylene resin particles
The proportion of particles having a particle size of 30 μm or more among particles made of polyethylene resin before use was calculated from the particle size distribution obtained by the Coal counter method.

(5) Melting point of particles made of polyethylene resin
The melting point of the polyethylene resin particles before use was measured using a differential scanning calorimeter (DSC) manufactured by SII with a sample weight of 10 mg and a heating rate of 10° C./min. The melting endothermic peak temperature detected here was taken as the melting point.

(6) Density, MFR and Melting Point of Polyethylene Resin Other Than the Particles Made of Polyethylene Resin The raw materials before film formation were each measured by the following methods.
The polyethylene resin forming the layer containing the particles made of polyethylene resin can be measured in the same manner as above, by scraping off the surface to a thickness less than the surface layer after confirming the layer structure with an electron microscope or the like for the entire layer if it is a single layer, or by scraping off the surface to a thickness less than the surface layer from the filtered solution obtained in (1) above and removing the solvent. When scraping off from a laminate, it can be performed by laminating it on a PET film or the like and then scraping off the surface layer with a razor or the like.

(density)
The measurement was performed by the density gradient tube method according to JIS-K7112.

(Melt flow rate: MFR) (g/10 min)
The measurement was performed at a temperature of 190° C. in accordance with JIS-K7210.

(Melting Point)
The measurement was performed using a differential scanning calorimeter (DSC) manufactured by SII with a sample weight of 10 mg and a heating rate of 10° C./min. The melting endothermic peak temperature detected here was taken as the melting point.

(7) Content (wt%) of inorganic particles in the resin composition
The content of the inorganic particles in the resin composition was calculated from the amount added in the raw material resin composition before processing.
Even after forming a film, it is possible to separate and measure the inorganic particles by dissolving the film in decane as a solvent at a temperature at which the film completely dissolves, and filtering the residue through a filter with a filtration accuracy of 1 to 2 μm.

(8) Residue amount after incineration of film (ppm)
About 30 g of the film was measured to the first decimal place using a precision balance (rounded off to the second decimal place). The crucible was pre-baked at 700°C for 1 hour, and after it had cooled to below 100°C, it was seasoned in a glass desiccator until it reached room temperature, and the weight of the crucible was measured. The film was then placed in the crucible and incinerated in an electric furnace at 700°C for 2 hours, and after the heater was turned off, it was transferred to a glass desiccator after it had cooled to about 100°C and seasoned for 30 minutes until it reached room temperature, and the difference in the crucible weight before and after incineration was divided by the weight of the film to calculate the amount of residue.

(9) Filter pressure increase (film forming processability)
The resin composition used in the sealing layer of Comparative Example 1 was passed through a Naslon sintered filter with a filtration accuracy of 120 μm using a Troughton testing machine at a resin temperature of 230° C. and discharged into a filtration area of 81π square millimeters at a discharge rate of 1 kg/hour for 5 hours. The amount of pressure rise (ΔMPa) was used as the standard (Δ), and the results were classified into the following categories: ◎, ○, △, ×.
⊚: The amount of pressure increase is 5% or less than that at the start of extrusion.
◯: The amount of pressure increase is 10% or less than that at the start of extrusion.
Δ: The amount of pressure increase is 15% or less than that at the start of extrusion.
x: The amount of pressure increase is 20% or less than that at the start of extrusion.

(10) Lip staining (film forming processability)
The resin composition used for the sealing layer was extruded at 230°C for 5 hours using an extruder with a strand die (2 holes, 5 mm diameter). The lip stains were visually observed and classified into the following categories of ◎, ○, △, and × based on the standard (△).
◎: Almost no lip stains can be seen.
○: Lip stains are slightly observed.
Δ: Lip stains are clearly visible.
×: The lip stain grew and a streak-like depression appeared in the strand.

(11) Three-dimensional surface roughness SRa
In accordance with JIS B0601-1994, a contact type surface roughness tester (manufactured by Kosaka Laboratory, model ET4000A) was used to measure 100 arbitrary locations of a measurement surface of 1 mm × 0.2 mm from a 3 cm × 3 cm square film piece, with a low cutoff λs of 0.08 mm, a length of 1000 μm, and a pitch of 2 μm.
From the obtained cross-sectional curve, the three-dimensional surface roughness SRa of the seal layer surface of the polyethylene-based resin multi-layer film was calculated using the three-dimensional surface roughness analysis program TDA-22 in accordance with JIS B0601-1994.
Measurements were carried out in the above manner (n=3), and the average value of the three-dimensional surface roughness SRx was calculated.

(12) Maximum projection height SRmax
In accordance with JIS B0601-1994, a contact type surface roughness tester (manufactured by Kosaka Laboratory, model ET4000A) was used to measure 100 arbitrary locations of a measurement surface of 1 mm × 0.2 mm from a 3 cm × 3 cm square film piece, with a low cutoff λs of 0.08 mm, a length of 1000 μm, and a pitch of 2 μm.
From the obtained cross-sectional curve, the three-dimensional surface roughness analysis program TDA-22 was used to calculate the maximum projection height SRmax in accordance with JIS B0601-1994.
Measurements were carried out in the above manner (n=3), and the average value of the maximum projection height SRmax was calculated.

(13) Heat seal initiation temperature (°C)
A dry lamination adhesive (TM569, CAT-10L) manufactured by Toyo-Morton was applied to the corona surface of a nylon film (biaxially oriented nylon film manufactured by Toyobo: N1100, 15 μm) to a solid content of 3 g/ ^m2 , and the solvent was removed by volatilization in an oven at 80°C. The corona surface of a polyethylene resin film and the adhesive-coated surface were then nipped and laminated on a temperature-controlled roll at 60°C. The laminated laminate film was aged at 40°C for 2 days. The prepared laminate sample was heat-sealed at a 10°C pitch with a sealing pressure of 0.1 MPa, a sealing time of 0.5 seconds, and a sealing temperature of 90 to 160°C, with a width of 10 mm. The heat-sealed sample was cut into strips with a heat seal width of 15 mm, and set in an autograph (Shimadzu Corporation, Model: UA-3122) to measure the maximum strength of the sealed surface peeled off at a speed of 200 mm/min (n=3), and the heat seal strength and heat seal temperature at each temperature were plotted. The heat seal temperature at which 4.9 N/15 mm was obtained was read from a graph connecting each plot with a straight line, and was regarded as the heat seal initiation temperature.

(14) Attained heat seal strength (N/15 mm)
A dry lamination adhesive (TM569, CAT-10L) manufactured by Toyo-Morton was applied to the corona surface of a nylon film (biaxially oriented nylon film manufactured by Toyobo: N1100, 15 μm) so that the solid content was 3 g/ ^m2 , and the solvent was removed by volatilization in an oven at 80°C. The corona surface of a polyethylene resin film and the adhesive-coated surface were then nipped and laminated on a temperature-controlled roll at 60°C. The laminated laminate film was aged at 40°C for 2 days. The prepared laminate sample was heat-sealed at a 10°C pitch with a sealing pressure of 0.1 MPa, a sealing time of 0.5 seconds, and a sealing temperature of 120 to 190°C, with a width of 10 mm. The heat-sealed sample was cut into a strip with a heat seal width of 15 mm, and set in an autograph (Shimadzu Corporation, Model: UA-3122). The maximum strength of the sealed surface peeled off at a speed of 200 mm/min was measured (n=3). The heat seal strength with the highest average value was recorded as the achieved seal strength.

(15) Blocking strength (mN/70 mm)
A laminate film with a nylon film (biaxially oriented nylon film N1100, 15 μm, manufactured by Toyobo) was prepared as follows.
A dry lamination adhesive (TM569, CAT-10L) manufactured by Toyo-Morton was applied to the corona surface of the nylon film to a solid content of 3 g/ ^m2, and the solvent was removed by volatilization in an oven at 80°C. After that, the corona surface of the polyethylene resin film and the adhesive-coated surface were nipped and laminated with a temperature-controlled roll at 60°C. The laminated laminate film was aged at 40°C for 2 days.
A sample (10 cm x 15 cm) with the A layer surfaces overlapping each other is placed in a heat press (manufactured by Tester Sangyo Co., Ltd., model: SA-303) so that the edges of an aluminum plate (2 mm thick) measuring 7 cm x 7 cm are aligned at a position 1 cm inside the center of the sample width (10 cm) and in the longitudinal direction (15 cm), and pressure treatment is performed at a temperature of 50°C, a gauge pressure of 18 MPa, and a time of 15 minutes.
The sample blocked by this pressure treatment and a bar (diameter 6 mm, material: aluminum) were attached to an autograph (Shimadzu Corporation, model: UA-3122) and the force required for the bar to peel off the blocked portion at a speed of 200 m/min was measured.
In this case, it is assumed that the bar and the peeled surface are horizontal. Four measurements were taken for each sample, and the average value was shown.

(16) Static Friction Coefficient A laminate film with a nylon film (biaxially oriented nylon film: N1100, 15 μm, manufactured by Toyobo) was prepared as follows.
A dry laminating adhesive (TM569, CAT-10L) manufactured by Toyo Morton was applied to the corona surface of the nylon film to a solid content of 3 g/ ^m2 , and the solvent was removed by volatilization in an oven at 80°C. The corona surface of the polyethylene resin film and the adhesive-coated surface were then nipped and laminated on a temperature-controlled roll at 60°C. The laminated laminate film was aged at 40°C for 2 days. The static friction coefficient between the polyethylene resin film surfaces of the prepared laminate film was measured in a 23°C, 65% RH environment in accordance with JIS-K-7125.

(17) Haze Only the polyethylene resin film was measured using a direct reading haze meter manufactured by Toyo Seiki Seisakusho Co., Ltd. in accordance with JIS-K-7105.
Haze (%) = [Td (diffuse transmittance %) / Tt (total light transmittance %)] x 100

(18) Flickering Only the polyethylene resin film was visually observed, and the flickering was classified into the following categories: ◎, ◯, △, ×.
: Almost no bright spots are noticeable.
◯: There are small bright spots, but they are uniform and not particularly noticeable.
Δ: There are some bright spots and a foreign body sensation is felt.
×: Bright spots are present all over the surface, impairing transparency.

(19) Scratch resistance (mechanical evaluation)
The scratch resistance was evaluated by setting the sealing surfaces of the films together in a Yasuda Seiki Gakushin type friction tester (friction tester type II, flat friction element 20 x 20 mm, test piece base, flat type, sliding arc length 100 mm) so that the surfaces to which the polyethylene resin particles were added were aligned, and the amount of change in haze after 40 times of friction with a load of 200 g was determined. The haze was measured by measuring the haze at the center of the friction table of the film (width x length = 30 mm x 180 mm, 50 x 50 mm for flat friction element) before setting it on the friction table, and measuring the haze at the same position before and after friction to determine the difference.

(20) Scratch resistance (visual evaluation)
A laminate film with a nylon film (biaxially oriented nylon film N1100, 15 μm, manufactured by Toyobo) was prepared as follows.
A dry lamination adhesive (TM569, CAT-10L) manufactured by Toyo Morton was applied to the corona surface of the nylon film to a solid content of 3 g/ ^m2 , and the solvent was removed by volatilization in an oven at 80°C. The corona surface of the polyethylene resin film and the adhesive-coated surface were then nipped and laminated on a temperature-controlled roll at 60°C. The laminated film was aged at 40°C for two days. The polyethylene resin film surfaces of the prepared laminated film were pinched with fingers so that they overlapped and rubbed 10 times, and visually observed, and the susceptibility to scratching was classified as follows: ◎, ○, △, ×.
◎: Almost no scratches.
◯: Thin streak-like scratches are observed, but no whitening occurs.
△: Thin, dense streaks and partial whitening are observed.
×: The rubbed area turns almost white.

Next, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited to the following examples.
The following raw materials were used in the examples and comparative examples.
(Polyethylene resin)
(1) Ube Maruzen Polyethylene Co., Ltd., Yumerit (registered trademark) 0540F (metallocene-based linear low-density polyethylene, density 904 kg/m ³ , MFR 4.0 g/10 min, melting point 111° C.)
(2) Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. (metallocene catalyst-based LLDPE, density: 913 kg/m ³ , MFR: 3.8 g/10 min, melting point: 115° C.)
(3) Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. (metallocene catalyst-based LLDPE, density: 923 kg/m ³ , MFR: 3.8 g/10 min, melting point: 118° C.)
(4) Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. (metallocene catalyst-based LLDPE, density: 930 kg/m ³ , MFR: 3.2 g/10 min, melting point: 124° C.)
(5) Ube Maruzen Polyethylene Co., Ltd. Yumerit (registered trademark) 3540FC (metallocene catalyst-based LLDPE, density: 931 kg/m ³ , MFR: 3.6 g/10 min, melting point: 123° C.)
(6) Ube Maruzen Polyethylene Co., Ltd. Yumerit (registered trademark) 4540F (metallocene catalyst-based LLDPE, density: 944 kg/m ³ , MFR: 4.0 g/10 min, melting point: 128° C.)

(Particles made of polyethylene resin)
(1) Mipelon PM200 manufactured by Mitsui Chemicals, Inc. (average particle size 10 μm, melting point 136° C., density 940 kg/m ³ , viscosity average molecular weight 1.8 million, ratio of particles with a particle size exceeding 30 μm is 0%, resin hardness D65, ultra-high molecular weight polyethylene particles)
(2) Mipelon XM221U manufactured by Mitsui Chemicals, Inc. (average particle size 25 μm, melting point 136, density 940 kg/m ³ , viscosity average molecular weight 2 million, ratio of particles with a particle size exceeding 30 μm is 25%, resin hardness D65, ultra-high molecular weight polyethylene particles)

(Inorganic particles)
(1) Grefco. Inc., Dicalite WF (diatomaceous earth, processed to an average particle size of 5 μm using a pin mill grinder)
(2) Shin-Etsu Silicone's KMP-130-10 (spherical silica particles, average particle size 10 μm) was used as a 15% MB based on Sumitomo Chemical's FV402.

(Master batch)
(1) Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was mixed with Mipelon PM200 to prepare a master batch (1) containing 15% by weight of Mipelon PM200.
(2) Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was mixed with Mipelon XM221U to prepare a master batch (2) containing 15% by weight of Mipelon XM221U.
(3) Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was mixed with Dicalite WF manufactured by Grefco. Inc. to prepare a master batch (3) containing 20% by weight of Dicalite WF manufactured by Grefco. Inc.
(4) Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was mixed with KMP-130-10 manufactured by Shin-Etsu Silicones Co., Ltd. to prepare a master batch (4) containing 15% by weight of KMP-130-10 manufactured by Shin-Etsu Silicones Co., Ltd.
(5) Erucamide was mixed with Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical to prepare a master batch (5) containing 4% by weight of erucamide.
(6) Ethylene bis oleamide was mixed with Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical to prepare a master batch (6) containing 2% by weight of ethylene bis oleamide.

Example 1
[Sealing layer composition]
A composition for a sealing layer was prepared using a mixture of 86.25% by weight of Umerit (registered trademark) 0540F manufactured by Ube Maruzen Polyethylene Co., Ltd., 4% by weight of master batch (1), 1.25% by weight of master batch (5), and 8.5% by weight of master batch (6).
[Laminate layer composition]
The laminate layer composition was prepared using only FV402 manufactured by Sumitomo Chemical Co., Ltd.
[Composition for intermediate layer]
A composition for an intermediate layer was prepared by mixing 99.4% by weight of FV402 manufactured by Sumitomo Chemical Co., Ltd., 0.5% by weight of master batch (5), and 0.1% by weight of master batch (6).
The laminate layer composition, the intermediate layer composition, and the seal layer composition were melt-extruded at 240°C using an extruder with a T-die in the order of the laminate layer composition, the intermediate layer composition, and the seal layer composition, and the thickness ratio of the laminate layer, the intermediate layer, and the seal layer was 8:34:8. Then, the laminate layer surface was subjected to corona discharge treatment. Then, the laminate layer was wound up on a roll at a speed of 150 m/min, and a polyethylene-based resin multilayer film with a thickness of 50 μm and a wet tension of the treated surface of 45 mN/m was obtained.

Example 2
In the sealing layer, 86% by weight of Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of master batch (1), 1.50% by weight of master batch (5), and 8.5% by weight of master batch (6) were mixed,
A polyethylene resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the laminate layer, Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was used alone.

Example 3
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 87.75% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of masterbatch (1), 1.25% by weight of masterbatch (5), and 7% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. was changed.

Example 4
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 84.75% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 8% by weight of masterbatch (1), 1.25% by weight of masterbatch (5), and 6% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. was changed.

Example 5
In the sealing layer, 86.75% by weight of Umerit (registered trademark) 3540F manufactured by Ube Maruzen Polyethylene Co., Ltd., 4% by weight of master batch (1), 1.75% by weight of master batch (5), and 7.5% by weight of master batch (6) were mixed,
In the middle layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Yumerit (registered trademark) 3540F manufactured by Ube Maruzen Polyethylene Co., Ltd.
A polyethylene resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the laminate layer, only Umerit (registered trademark) 3540F manufactured by Ube Maruzen Polyethylene Co., Ltd. was used.

Example 6
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 86.75% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of masterbatch (1), 0.5% by weight of masterbatch (3), 1.25% by weight of masterbatch (5), and 7.5% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. was changed.

(Example 7)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 87.25% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of masterbatch (1), 1.25% by weight of masterbatch (5), and 7.5% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. was changed.

The polyethylene resin films obtained in Examples 1 to 7 contained almost no inorganic particles larger than the particle size of the polyethylene resin particles, and therefore had excellent scratch resistance, low-temperature heat sealability, blocking resistance, slipperiness, and appearance.
Moreover, the film had excellent processability in film formation, with very little residue when incinerated and almost no eye tar or filter pressure buildup.

(Comparative Example 1)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 82.25% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 2.5% by weight of masterbatch (3), 8% by weight of masterbatch (4), 1.25% by weight of masterbatch (5), and 6% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was changed.
The film obtained in Comparative Example 1 had excellent blocking resistance and slippage, but had a slight flickering sensation, had a large amount of inorganic residue after incineration, was particularly poor in scratch resistance, and was also slightly poor in film-forming processability.

(Comparative Example 2)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 90.25% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 2.5% by weight of masterbatch (3), 1.25% by weight of masterbatch (5), and 6% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was changed.
The film obtained in Comparative Example 2 had relatively little residue and was excellent in terms of flickering, but was poor in blocking resistance, scratch resistance and slipperiness.

(Comparative Example 3)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 87.75% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 1% by weight of masterbatch (1), 2.5% by weight of masterbatch (3), 1.25% by weight of masterbatch (5), and 7.5% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd. was changed.
The film obtained in Comparative Example 3 had relatively few residues and was slightly superior in scratch resistance, but had few protrusions and was inferior in blocking resistance.

(Comparative Example 4)
In the sealing layer, 87.25% by weight of Umerit (registered trademark) 4540F manufactured by Ube Maruzen Polyethylene Co., Ltd., 4% by weight of master batch (1), 1.25% by weight of master batch (5), and 7.5% by weight of master batch (6) were mixed,
In the middle layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Yumerit (registered trademark) 4540F manufactured by Ube Maruzen Polyethylene Co., Ltd.
A polyethylene resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the laminate layer, only Umerit (registered trademark) 4540F manufactured by Ube Maruzen Polyethylene Co., Ltd. was used.
The film obtained in Comparative Example 4 had relatively little residue and excellent scratch resistance, but the high resin density caused the surface protrusions made of polyethylene particles to be unstable, and the blocking resistance and slipperiness were insufficient and varied greatly.

(Comparative Example 5)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that in the seal layer, 87.25% by weight of Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of masterbatch (2), 1.25% by weight of masterbatch (5), and 7.5% by weight of masterbatch (6) were mixed, in the intermediate layer, Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd. was changed to Sumikathene (registered trademark) E FV405 manufactured by Sumitomo Chemical Co., Ltd., and in the laminate layer, only Sumikathene (registered trademark) E FV407 manufactured by Sumitomo Chemical Co., Ltd. was changed.
The film obtained in Comparative Example 5 had little residue and excellent scratch resistance, but because the particle diameter was large even though a large amount was added, the protrusion density was low and blocking resistance and flickering were poor.

(Comparative Example 6)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 1, except that a composition for the sealing layer was prepared using a mixture of 86.25% by weight of Umerit (registered trademark) 0540F manufactured by Ube Maruzen Polyethylene Co., Ltd., 4% by weight of masterbatch (1), 1.25% by weight of masterbatch (5), and 5.0% by weight of masterbatch (6).

(Comparative Example 7)
A polyethylene-based resin multilayer film and a vapor-deposited film were obtained in the same manner as in Example 2, except that a composition for a sealing layer was prepared by mixing 95.90% by weight of Sumikathene (registered trademark) E FV402 manufactured by Sumitomo Chemical Co., Ltd., 4% by weight of masterbatch (1), 1.25% by weight of masterbatch (5), and 5.0% by weight of masterbatch (6).

The results are shown in Tables 1 and 2.

The polyethylene resin film of the present invention has been described above based on several examples, but the present invention is not limited to the configurations described in the above examples, and the configuration can be changed as appropriate within the scope of the spirit of the present invention, such as by appropriately combining the configurations described in each example.

The polyethylene resin film described in this invention has excellent properties and can be suitably used as a film for a wide range of applications, including food packaging.

Claims (8)

The present invention has at least a layer A made of a polyethylene-based resin composition, and the polyethylene-based resin composition constituting the layer A satisfies the following 1) to 3),
and at least one surface of the layer A satisfies both of the following 4) and 5).
1) Contains a polyethylene resin having a density of 900 kg/m3 or more and 935 kg/m3 ^{or less} .
2) It contains particles made of a polyethylene resin having an average particle size of 5 to 20 μm .
3) The content of the organic lubricant is 0.16% by weight or more.
4) The three-dimensional surface roughness SRa is 0.05 to 0.2 μm.
5) The maximum peak height SRmax is 2 to 15 μm. The polyethylene resin multilayer film according to claim 1, wherein the resin hardness of the particles made of the polyethylene resin is D70 or less. 3. The polyethylene resin film according to claim 1, wherein the particles made of the polyethylene resin have a viscosity average molecular weight of 1,500,000 or more. 3. The polyethylene resin film according to claim 1 , wherein the content of the polyethylene resin particles in the polyethylene resin composition constituting the layer A is 0.2 to 2.0% by mass. 3. The polyethylene resin film according to claim 1, wherein the blocking value between the surfaces of the layer A is 200 mN/70 mm or less. 3. The polyethylene resin film according to claim 1, wherein the change in haze after 100 abrasion cycles at a load of 200 g when the A layer surfaces are placed against each other in a Gakushin abrasion tester manufactured by Yasuda Seiki is 3% or less. A laminate comprising the polyethylene resin film according to any one of claims 1 to 6 and a substrate film made of a thermoplastic resin composition. A packaging bag comprising the laminate according to claim 7 .