JP6798967B2 - Sealant film, and packaging materials and packaging bags using it - Google Patents

Description

The present invention relates to a sealant film containing a plant-derived polyethylene-based resin, and a packaging material and a packaging bag using the same. More specifically, the present invention exhibits a high degree of biomass but a high lamination strength with an adjacent layer. Moreover, the present invention relates to a sealant film having excellent slipperiness, and a packaging material and a packaging bag using the same.

In recent years, in order to reduce the burden on the environment, it has been possible to replace a part of the raw material of the resin film from a petroleum-derived resin with a resin containing a plant-derived component as a main component (hereinafter referred to as "plant-derived resin"). It is being studied (Patent Document 1). The plant-derived resin is expected to have the same physical properties as the conventional petroleum-derived resin in terms of chemical structure.

However, in reality, a resin film containing a plant-derived resin, for example, a sealant film containing a plant-derived polyethylene-based resin exhibits properties different from those of a sealant film composed only of a petroleum-derived polyethylene-based resin.

For example, in a sealant film containing a polyethylene-based resin derived from petroleum, when a part of the polyethylene-based resin as a raw material is changed to a polyethylene-based resin derived from a plant, a base material laminated on the polyethylene resin as the blending ratio increases. It was found that the lamination strength with the layer was lowered and delamination was likely to occur.

Therefore, it has been difficult to achieve both high lamination strength with the base material layer and high biomass degree.
In response to this problem, the presence of the bleed-out inhibitor in the sealant film made it possible to increase the lamination strength with the base material layer, but on the other hand, there was a problem that the slipperiness was lowered.

Then, as the slipperiness of the sealant film decreases, a so-called blocking phenomenon occurs in which the films adhere to each other in the film forming process, the slitting process, the bag making process, the content filling process, and the like, so that wrinkles may occur. If the film is stored for a long period of time or stored at a high temperature, the film expandability deteriorates during use, and the bag making workability, filling workability, etc. are significantly deteriorated.

JP-A-2009-155516

The present invention solves the above problems, exhibits high lamination strength with the base material layer, has excellent slipperiness, and exhibits a high biomass degree of at least 45% as a whole film, so that the load on the environment is reduced. It is an object of the present invention to provide a sealant film, and a packaging material and a packaging bag using the same.

As a result of various studies, the present inventor has found that the decrease in laminate strength that occurs as the blending ratio of the plant-derived polyethylene-based resin increases on the film surface of low-molecular-weight compounds such as monomers and oligomers in the plant-derived polyethylene-based resin. It was found that it was caused by bleed-out (precipitation). Further, in a sealant film containing a plant-derived polyethylene-based resin, the laminated surface of the base material layer is covered with a layer made of only petroleum-derived polyethylene-based resin, so that the base material of the low molecular weight compound is not deteriorated in slipperiness. It has been found that bleed-out to the layer-laminated surface can be prevented and the lamination strength with the base material layer can be increased.

The present invention is characterized by the following points.
1. 1. A sealant film used by being laminated on a base material layer, which is a multilayer laminated film composed of one layer or more of a layer made of petroleum-derived polyethylene resin and one layer or more of a layer made of plant-derived polyethylene-based resin. The above-mentioned sealant film, wherein the outermost surface layer forming the base material layer laminated surface is a layer made of a polyethylene-based resin derived from petroleum, and the biomass degree of the entire sealant film is 45 to 80%.
2. The above-mentioned 1. The sealant film described in.
3.2 A three-layer laminated film composed of two layers of petroleum-derived polyethylene-based resin and one layer of plant-derived polyethylene-based resin, the outermost layer forming the base material layer laminated surface, and The outermost layer forming the heat-sealed surface on the opposite side is a layer made of a polyethylene-based resin derived from petroleum, and the intermediate layer between them is a layer made of a polyethylene-based resin derived from a plant. The sealant film described in.
4. The base material layer and the above 1. ~ 3. A packaging material having a layer made of the sealant film according to any one of.
5. Above 4. A packaging bag made of the packaging material described in.
6. The above 5. Standing pouch for refilling. The packaging bag described in.

The sealant film of the present invention contains a plant-derived resin in a high blending ratio, that is, has a high biomass degree. Therefore, from the viewpoint of carbon neutrality, it suppresses the increase in the amount of CO _{2 in} the atmosphere and contributes to the saving of petroleum resource utilization.

In addition, carbon neutral means that even if a plant is burned, the amount of CO ₂ emitted at that time is equal to the amount of CO ₂ absorbed by the plant during growth, so it affects the increase or decrease in the amount of CO _{2 in} the atmosphere. Refers to not. Therefore, the more plant-derived raw materials are contained, the more the increase in CO ₂ amount can be suppressed.

Further, the sealant film of the present invention has little change in various physical properties of the film surface even after the film is stored for a long period of time, for example, after being exposed to sunlight for a long period of time, and has a high base layer. It exhibits laminating strength and excellent slipperiness, and is less likely to cause deterioration over time and accompanying delamination, adhesion between films, and the like. That is, it exhibits excellent weather resistance.

Further, in the present invention, the outermost layer forming the base material layer laminated surface is a layer made of a petroleum-derived polyethylene-based resin, and various physical properties of the petroleum-derived polyethylene-based resin have been developed. Therefore, the petroleum-derived polyethylene-based resin that forms the base material layer laminated surface can be appropriately selected from a wide variety of options, and the lamination strength with the base material layer, the laminating conditions, and the like can be easily adjusted.

Similarly, when the outermost layer forming the heat-sealing surface is a layer made of a petroleum-derived polyethylene-based resin, a petroleum-derived polyethylene-based material suitable for the desired heat-sealing strength and heat-sealing conditions can be selected from a wide variety of options. The resin can be appropriately selected.

Further, the packaging material and the packaging bag composed of the sealant film and the base material layer of the present invention can suppress the decrease in interlayer adhesive strength even after being subjected to the heating / cooling process, and have excellent bag making workability and the like. Therefore, it is useful as various packaging materials.

It is the schematic sectional drawing which shows an example about the layer structure of the sealant film of this invention. It is the schematic sectional drawing which shows another example about the layer structure of the sealant film of this invention. It is the schematic sectional drawing which shows an example about the layer structure of the packaging material of this invention.

The above invention will be described in more detail below. Hereinafter, the resin names used in the present invention will be those commonly used in the industry. In the present invention, the density is a value measured according to JIS-K7112. Further, MFR is a value measured in accordance with JIS-K7210.

<I> Layer structure of the sealant film of the present invention FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the sealant film of the present invention. As shown in FIG. 1, in the sealant film of the present invention, an arbitrary base material layer is laminated on one surface, that is, the base material layer laminated surface [A], and the heat-sealed surface [A] is the other surface. B] is placed so as to face an arbitrary adherend and superposed, and heat-sealed for use. In the following specification, the surface of the sealant film in contact with the base material layer is referred to as a "base material layer laminated surface", and the surface of the sealant film in contact with the adherend is referred to as a "heat seal surface".

Here, the sealant film is a two-layer laminated film composed of one layer [1] made of a petroleum-derived polyethylene resin and one layer [2] made of a plant-derived polyethylene resin. With this configuration, a sealant film showing good lamination strength with the base material layer and excellent slipperiness and showing a high degree of biomass can be produced easily and at low cost with good productivity.

FIG. 2 is a schematic cross-sectional view showing an example of the layer structure of the sealant film of the present invention. As shown in FIG. 2, the sealant film of the present invention includes two layers of petroleum-derived polyethylene-based resin [1, 3] and a layer of plant-derived polyethylene-based resin sandwiched between them [2]. It may be a three-layer laminated film made of. With this structure, it is possible to produce a sealant film showing a high degree of biomass while exhibiting good lamination strength with the base material layer, excellent slipperiness, and good heat sealability.

FIG. 3 is a schematic cross-sectional view showing an example of the layer structure of the packaging material of the present invention. As shown in FIG. 3, the packaging material of the present invention is formed by laminating a base material layer [4] on a base material layer laminated surface of the sealant film of the present invention.

The sealant film of the present invention may have an arbitrary thickness depending on its use, desired seal strength, desired biomass degree, desired weather resistance, etc., but is generally about 5 to 200 μm as a sealant film. It is preferably 20 to 150 μm. Further, when the use is a heavy bag or a packaging bag for a standing pouch for refilling, the thickness is preferably 100 to 150 μm.

Then, in the sealant film, the ratio of the thickness of each layer is set so that the biomass degree of the entire sealant film is 45 to 80%, more preferably 50 to 80%.
The larger the ratio of the thickness of the layer made of the plant-derived polyethylene resin, the higher the degree of biomass is achieved. However, when this layer is too thick as compared with the layer [1] made of petroleum-derived polyethylene resin forming the base material layer laminated surface and the biomass degree exceeds 80%, the low molecular weight compound is applied to the film surface. Bleed-out cannot be sufficiently prevented, and the desired lamination strength cannot be obtained when the base material layers are laminated.

The layer thickness of the layer [1] made of petroleum-derived polyethylene resin forming the base layer laminated surface is at least 0.1 μm, and is preferably 3 μm or more in the case of a heavy-duty bag or a packaging bag for a standing pouch for refilling. Moreover, the thickness is such that the biomass degree of the entire sealant film is 45 to 80%.

<II> Layer made of plant-derived polyethylene resin In the present invention, "plant-derived" means containing carbon derived from a plant-derived material, which is produced from an alcohol obtained from a plant as a raw material.

In the present invention, the plant-derived polyethylene-based resin is a homopolymer of plant-derived ethylene derived from bioethanol obtained from a plant raw material, or a copolymer of the plant-derived ethylene and a small amount of other comonomer. ..

Specifically, high-density polyethylene (HDPE, density 0.940 g / cm ³ or more) obtained by polymerizing ethylene derived from bioethanol, medium-density polyethylene (MDPE, density 0.925 or more, 0.940 g / cm or more). Less than ³ ), high pressure method low density polyethylene (LDPE,
Density less than 0.925 g / cm ³ ), linear low density polyethylene (LLDPE, density 0.91)
0 to 0.925 g / cm ³ , a copolymer of ethylene and α-olefin), and mixtures thereof.

For example, in order to apply it to a sealant for a heavy bag or a standing pouch, it is particularly preferable to use plant-derived LLDPE because the film has an appropriate waist and excellent impact resistance.

Examples of the α-olefin serving as the comonomer of the LLDPE include α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene and 4-methylpentene. Etc., and mixtures thereof. These α-olefins may be plant-derived α-olefins derived from bioethanol or non-plant-derived, that is, petroleum-derived α-olefins. Since a wide variety of petroleum-derived α-olefins are available, the physical properties of polyethylene-based resins can be easily adjusted by producing them. By using the plant-derived α-olefin, the biomass degree of the final product can be further increased.

As a method for producing plant-derived ethylene and plant-derived α-olefin, bioethanol is produced by fermenting sugar solution or starch obtained from plants such as sugar cane, corn, and sweet potato with microorganisms such as yeast according to a conventional method. Then, this is heated in the presence of a catalyst, and plant-derived ethylene and plant-derived α-olefin (1-butene, 1-hexene, etc.) can be obtained by an intramolecular dehydration reaction or the like. Then, the plant-derived ethylene and the plant-derived α-olefin can be used to produce a plant-derived polyethylene-based resin in the same manner as in the production of a petroleum-derived polyethylene-based resin.

Methods for producing plant-derived ethylene, plant-derived α-olefin, and plant-derived polyethylene-based resin are described in detail in, for example, Japanese Patent Publication No. 2011-506628.
As a plant-derived polyethylene resin preferably used in the present invention, Braskem (
Examples include green PE manufactured by Braskem SA).

In the sealant film of the present invention, the "layer made of plant-derived polyethylene-based resin" is a layer formed by melting the above-mentioned plant-derived polyethylene-based resin and coextruding it together with a multilayer material resin. Here, in the plant-derived polyethylene-based resin, a small amount, for example, 5% by mass or less of an additive, specifically, a slip agent (lubricant) is contained, as long as the effect of the present invention is not impaired. , Antistatic agents, flame retardants, anti-blocking agents, crystallization accelerators, stabilizers (anti-aging agents, antioxidants, ozone deterioration inhibitors, UV absorbers, light stabilizers, etc.), tackifiers, softeners , Coloring agent, coupling agent, preservative, antifungal agent and the like may be added.

<III> Layer made of petroleum-derived polyethylene resin In the present invention, "petroleum-derived" is derived from ethylene obtained by thermally decomposing naphtha obtained from petroleum as before, without containing carbon derived from plant raw materials. The main component is the structure to be used.
The petroleum-derived polyethylene-based resin used in the present invention is any polyethylene-based resin generally used as a sealant film having heat-sealing properties.

More specifically, it is a homopolymer of petroleum-derived ethylene or a copolymer of petroleum-derived ethylene and a small amount of other comonomer, and is a high-density polyethylene (HDPE, density 0.940).
g / cm ³ or more), medium density polyethylene (MDPE, density 0.925 or more, 0.940 g / c)
M ³ ), high pressure method low density polyethylene (LDPE, density less than 0.925 g / cm ³ ), linear low density polyethylene (LLDPE, density 0.910 to 0.925 g / cm ³ , ethylene and α-olefin Copolymers of), and mixtures thereof. Examples of the α-olefin serving as the comonomer of the LLDPE include α-olefins having 3 to 20 carbon atoms, such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-nonene and 4-methylpentene. Etc., and mixtures thereof.

The petroleum-derived polyethylene-based resin may have arbitrary properties in terms of molecular weight, MFR, etc., depending on the type of base material layer and adherend to be laminated in a later step, and desired sealing strength. It can be appropriately determined by those skilled in the art according to the hot tack property, the heat sealing condition to be selected, and the like.

For example, it is particularly preferable to use petroleum-derived LLDPE or a mixture of petroleum-derived LLDPE and petroleum-derived LDPE for application to a sealant for a heavy bag or a standing pouch. As a result, an appropriate waist can be obtained for the film, and excellent impact resistance can be obtained. Further, as the material resin of the layer made of petroleum-derived polyethylene resin, petroleum-derived LLDPE or a mixture of petroleum-derived LLDPE and petroleum-derived LDPE is used, and further, as the material resin of the layer made of plant-derived polyethylene-based resin, a plant It is more preferable to use the derived LLDPE because the adhesiveness between the layers of the sealant film is enhanced.

In the sealant film of the present invention, the "layer made of petroleum-derived polyethylene-based resin" is a layer formed by melting the petroleum-derived polyethylene-based resin and coextruding it together with a multilayer material resin. Here, in the petroleum-derived polyethylene-based resin, as long as the effect of the present invention is not impaired, a small amount, for example, 5% by mass or less of an additive, specifically, a slip agent (lubricant) , Antistatic agents, flame retardants, anti-blocking agents, crystallization accelerators, stabilizers (anti-aging agents, antioxidants, ozone deterioration inhibitors, UV absorbers, light stabilizers, etc.), tackifiers, softeners , Coloring agent, coupling agent, preservative, antifungal agent and the like may be added.

<IV> Film formation The sealant film of the present invention can be produced by preparing a resin or a resin composition constituting each layer, melt-kneading, and then co-extruding using a conventional film molding method.
The resin film is required to have slipperiness in order to ensure processing suitability. Then, if necessary, a slipper-imparting agent such as a slip agent or an antistatic agent is blended in the film to improve the slipperiness. However, the improvement in slipperiness generally results in a decrease in the laminate strength of the film.

In response to this problem, the sealant film of the present invention has a layer made of petroleum-derived polyethylene resin as the outermost layer forming the base material layer laminated surface. This layer suppresses the bleed-out of the low molecular weight compound contained in the plant-derived polyethylene-based resin to the laminated surface of the base material layer even when the sealant film of the present invention contains a slipper-imparting agent such as a slip agent. However, it does not inhibit the effect of the slippery imparting agent. Therefore, the sealant film of the present invention can exhibit excellent slipperiness while exhibiting high lamination strength.

<V> Base material layer The sealant film of the present invention can be used as a laminate in which various base material layers are laminated depending on the intended use.
The base material to be laminated on the sealant film of the present invention may be metals, ceramics, woods, papers, etc., but in the field of packaging materials, films and / or papers made of thermoplastic resins. In many cases.

The thermoplastic resins constituting the base material include olefin resins (polyethylene resins, polypropylene resins, etc.), halogen-containing resins (vinyl chloride resins, etc.), vinyl alcohol resins, (meth) acrylic resins, and styrene resins. Resins, polyester resins (polyalkylene allylate resins such as polyethylene terephthalate, polyethylene naphthalate, and polybutylene terephthalate), polyamide resins (polyamide 6, polyamide 66, etc.), polycarbonate resins, polysulfone resins (polyether sulfone, etc.) Polysulfone, etc.), polyphenylene ether-based resins, cellulose esters, etc. can be exemplified.

Further, in order to increase the degree of biomass, the base film may also be a plant-derived resin film. Such a film can be made of a polylactic acid-based resin, a polyester-based resin, a polyamide-based resin, or the like. These films may be formed of a single thermoplastic resin, or may be a composite (alloy-based film) or a laminate composed of two or more kinds of thermoplastic resins. Of these films, polypropylene-based resin films, polyester-based resin films, polyamide-based resin films, polylactic acid-based resin films, and the like are often used.
These base films may be non-stretched or may be uniaxial or biaxially stretched films.

Further, these base films may be composite films in which two or more are laminated. Further, any barrier film, for example, a material having a property of blocking light such as sunlight or a property of not transmitting gas such as water vapor, water, and oxygen can be used.

Specifically, for example, a metal foil such as an aluminum foil, a resin film having a vapor-deposited film such as aluminum, silicon oxide having a barrier property, a resin film having an inorganic oxide vapor-deposited film such as aluminum oxide, water vapor, water, etc. Resin film with barrier property, polyvinyl alcohol with gas barrier property, saponified ethylene-vinyl acetate copolymer, resin film such as MXD6 nylon, light-shielding property made by kneading resin with colorant such as pigment. Various colored resin films and the like can be used.

Further, the laminated surface of these base films may be surface-treated (for example, corona discharge treatment, anchor coating treatment, primer treatment, etc.) in order to enhance the adhesion to the sealant film of the present invention. The thickness of the base film is not particularly limited, and can be usually selected from the range of 1 μm to 2 mm, preferably about 5 μm to 1 mm, depending on the application.

<VI> Lamination The lamination of the base material layer and the sealant film can be laminated by a dry laminating method via an adhesive. Examples of the adhesive to be used include a two-component curable polyurethane adhesive for dry laminating.

It can also be bonded by an extrusion laminating method (so-called sandwich laminating method) via an adhesive layer. In this case, as the adhesive layer, a polyolefin-based thermosetting resin such as LDPE, an ethylene-methacrylic acid copolymer, an ethylene-acrylic acid copolymer, a simple substance such as ionomer, or a hard resin or the like may be used. A resin or the like blended with an adhesiveness improver can be used.

Further, the resin constituting the sealant film of the present invention can be laminated on the base film by extrusion coating.
In a further aspect of the present invention, a printing layer such as characters, figures, symbols, and patterns may be provided on the base film or between the sealant film and the base film.
By using an adhesive or printing ink containing a plant-derived resin as the adhesive or printing ink used above, the degree of biomass can be further increased.

<VII> Packaging Material The laminated film having the above-mentioned base material layer and the sealant film of the present invention can be suitably used as a packaging material for a lid material, a packaging bag, or the like. For example, the laminated film is folded in half, or two laminated films are prepared, the surfaces of the sealant film are overlapped with each other facing each other, and the peripheral end thereof is, for example, a side seal type or a two-way seal. Heat seal by heat seal form such as mold, three-sided seal type, four-sided seal type, envelope-attached seal type, gassho-attached seal type (pillow seal type), fold seal type, flat-bottom seal type, square-bottom seal type, gusset type, etc. It can be made into various forms of packaging bags.

In the above, as the heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, and an ultrasonic seal can be used.

The sealant film of the present invention exhibits a high degree of biomass, yet exhibits a high lamination strength with an adjacent base material layer, and also exhibits excellent slipperiness. Therefore, it can be suitably used as a packaging material for various purposes. In particular, the packaging material using the sealant film of the present invention can be suitably used as a heavy-duty bag or a standing pouch for refilling, which has a large content with respect to the area of the film used.

<VIII> Biomass degree "Biomass degree" is an index showing the mixing ratio of petroleum-derived raw materials and plant-derived raw materials (biomass), and is determined by measuring the concentration of radiocarbon (C ¹⁴ ). , Expressed by the following formula.
Biomass degree (%) = C ¹⁴ concentration (pMC) x 0.935
This C ¹⁴ is contained in a certain concentration in plant-derived raw materials, but is hardly present in petroleum confined in the ground. Therefore, by measuring the concentration of C ¹⁴ by accelerator mass spectrometry, it can be used as an index of the content ratio of plant-derived raw materials.

The sealant film of the present invention contains a high blending ratio of a plant-derived resin while exhibiting excellent weather resistance and high lamination strength with an adjacent layer, and has a high biomass of 45 to 80%, more preferably 50 to 80%. Can indicate the degree. If the layer made of the plant-derived polyethylene resin is thickened so that the biomass content exceeds 80%, bleeding out to the film surface cannot be sufficiently prevented, and the desired lamination strength is obtained when the base material layer is laminated. I can't.

In the present invention, the concentration of C ¹⁴ in the film is measured as follows. That is, the sample to be measured is burned to generate carbon dioxide, and the carbon dioxide purified in the vacuum line is reduced with hydrogen using iron as a catalyst to purify graphite. Then, the graphite, by mounting the C ¹⁴ AMS-only apparatus which is based on Tandem accelerator (manufactured by NEC Corporation), the count of C ^14, the concentration of the concentration ^{(C 13 / C 12),} C 14 of C ¹³ ( C ¹⁴ / C ¹² ) is measured, and the ratio of the C ¹⁴ concentration of the sample carbon to the standard modern carbon is calculated from this measured value. As a standard sample, oxalic acid (HOXII) provided by the National Institute of Standards and Standards (NIST) is used.

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.
[Example 1]
Petroleum-derived LLDPE (Prime Polymer Co., Ltd. Evolu SP2020, density 0.9
16 kg / m ³ , MFR = 2.3 g / 10 minutes) 99% by mass and 1% by mass of slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) are sufficiently melt-kneaded to prepare the first resin composition. did.
In addition, plant-derived LLDPE (C4-SLL118 manufactured by Braskem, density 0.916 kg)
/ M ³ , MFR = 1.0 g / 10 minutes, biomass degree 87%) 99% by mass and slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) 1% by mass are sufficiently melt-kneaded and kneaded to the second resin. The composition was adjusted.
Using the first and second resin compositions, a film is formed by a top-blown air-cooled inflation coextrusion film forming machine, and the first resin composition (base material layer laminated surface, thickness 25 μm) / second resin composition The sealant film of the present invention was produced, which consisted of three layers of a product (intermediate layer, thickness 70 μm) / first resin composition (heat-sealed surface, thickness 25 μm). The biomass degree was 50%.

[Example 2]
Petroleum-derived LLDPE (Prime Polymer Co., Ltd. Evolu SP2020, density 0.9
16kg / m ³ , MFR = 2.3g / 10 minutes) 70% by mass, petroleum-derived LDPE (LDPE-F120N manufactured by Ube-Maruzen Polyethylene Co., Ltd., density 0.920kg / m ³ , MFR = 1.2g
/ 10 min) 29% by mass and 1% by mass of slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) were sufficiently melt-kneaded to prepare a first resin composition.
In addition, plant-derived LLDPE (C4-SLL118 manufactured by Braskem, density 0.916 kg)
/ M ³ , MFR = 1.0 g / 10 minutes, biomass degree 87%) 99% by mass and slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) 1% by mass are sufficiently melt-kneaded and kneaded to the second resin. The composition was adjusted.

Using the first and second resin compositions, a film is formed by a top-blown air-cooled inflation coextrusion film forming machine, and the first resin composition (base material layer laminated surface, thickness 25 μm) / second resin composition The sealant film of the present invention was produced, which consisted of three layers of a product (intermediate layer, thickness 70 μm) / first resin composition (heat-sealed surface, thickness 25 μm). The biomass degree was 50%.

[Example 3]
Petroleum-derived LLDPE (Prime Polymer Co., Ltd. Evolu SP2020, density 0.9
16 kg / m ³ , MFR = 2.3 g / 10 minutes) 99% by mass and 1% by mass of slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) are sufficiently melt-kneaded to prepare the first resin composition. did.
In addition, plant-derived LLDPE (C4-SLL118 manufactured by Braskem, density 0.916 kg)
/ M ³ , MFR = 1.0 g / 10 minutes, biomass degree 87%) 99% by mass and slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) 1% by mass are sufficiently melt-kneaded and kneaded to the second resin. The composition was adjusted.
Using the first and second resin compositions, a film is formed by a top-blown air-cooled inflation coextrusion film forming machine, and the first resin composition (base material layer laminated surface, thickness 10 μm) / second resin composition The sealant film of the present invention was produced, which consisted of two layers of an object (heat-sealed surface, thickness 120 μm). The biomass degree was 80%.

[Comparative Example 1]
Plant-derived LLDPE (C4-SLL118 manufactured by Brasschem, density 0.916 kg / m ³ , MFR = 1.0 g / 10 minutes, biomass degree 87%) 58% by mass, petroleum-derived LLDPE (((
Evolu SP2020 manufactured by Prime Polymer Co., Ltd., density 0.916 kg / m ³ , MFR = 2.3 g / 10 minutes) 12% by mass, petroleum-derived LDPE (LDP manufactured by Ube-Maruzen Polyethylene Co., Ltd.)
E-F120N, density 0.920 kg / m ³ , MFR = 1.2 g / 10 minutes) 29% by mass, and slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) 1% by mass are sufficiently melt-kneaded to obtain. The resulting resin composition was formed by a top-blown air-cooled inflation coextrusion film forming machine to produce a sealant film having a thickness of 120 μm. The biomass degree was 50%.

[Comparative Example 2]
Petroleum-derived LLDPE (Prime Polymer Co., Ltd. Evolu SP2020, density 0.9
16kg / m ³ , MFR = 2.3g / 10 minutes) 70% by mass, petroleum-derived LDPE (LDPE-F120N manufactured by Ube-Maruzen Polyethylene Co., Ltd., density 0.920kg / m ³ , MFR = 1.2g
/ 10 min) 29% by mass and 1% by mass of slip agent (M-3 manufactured by Nippon Unicar Co., Ltd.) are sufficiently melt-kneaded, and the obtained resin composition is manufactured by a top-blown air-cooled inflation coextrusion film-forming machine. The film was formed to produce a sealant film having a thickness of 120 μm. The biomass degree was 0%.

[Evaluation]
(Laminate strength)
Corona treatment is applied to one surface of the base layer laminated surface of the sealant films of Examples 1 to 3 and the sealant film of Comparative Examples 1 and 2, and the treated surface is biaxially stretched nylon via an adhesive layer. A laminated film was prepared by dry laminating a film (thickness 15 μm). This laminated film was aged at 40 ° C. for 3 days, and the lamination strength after 2 weeks at 23 ° C. was measured at T-type peeling and tensile speed of 50 mm / min per 15 mm width.

(Hand cutting)
For the sealant films of Examples 1 to 3 and Comparative Examples 1 and 2, laminated films were produced in the same manner as in the above-mentioned laminating strength measurement. The two obtained laminated films were laminated so that the MD and TD were aligned, and the tear strength in the MD direction and the TD direction was measured in accordance with JIS K7128-2 (Elemendorff tear method).

(Slipperiness)
Two sealant films of Examples 1 to 3 and Comparative Examples 1 and 2 were prepared, and the slipperiness of the film (heat-sealed surface) to the film (heat-sealed surface) was determined in JIS K7125: 1999 (coefficient of friction test method). The coefficient of dynamic friction was measured according to this.
The results are shown in Table 1 below.

Although the sealant films of Examples 1 to 3 have a high biomass degree of 50 to 80%, they have excellent lamination strength equivalent to that of the sealant film of Comparative Example 2 (biomass degree of 0%). However, the hand-cutting property and slipperiness were also good. On the other hand, the sealant film of Comparative Example 1 was inferior in lamination strength.

(Appearance of pouch)
For the sealant films of Examples 1 to 3 and Comparative Examples 1 and 2, laminated films were produced in the same manner as in the above-mentioned laminating strength measurement to obtain a packaging material for the body material of the pouch.
Separately from this, using the first resin composition of Example 1, a film was formed by a top-blown air-cooled inflation coextrusion film forming machine to prepare a single-layer sealant film (thickness 130 μm). With respect to the obtained sealant film, a laminated film was prepared in the same manner as in the above-mentioned laminating strength measurement to obtain a packaging material for the bottom material of the pouch.

Using the obtained packaging materials for the body material and the bottom material, a standing pouch having external dimensions: height 230 mm × width 130 mm, bottom folded portion height 40 mm, and seal width 5 mm was manufactured. In addition, the bottom was heat-sealed with a boat bottom type seal pattern.

Ten pouches produced as described above were prepared for each Example / Comparative Example, and each pouch was filled with 380 cc of water, heat-sealed and sealed. Then, after storing these pouches at 3 ° C. for 3 days, from a height of 1.2 m, horizontal to the floor (so that the body touches the floor) 5
The pouch was dropped 5 times and vertically perpendicular to the floor (so that the bottom touched the floor), and the change in the appearance of the pouch was visually observed.
The results are shown in Table 2 below.

The pouches using the sealant films of Examples 1 to 3 and Comparative Example 2 maintained a beautiful appearance even after the test. On the other hand, the pouch using the sealant film of Comparative Example 1 was subjected to the impact of dropping, and delamination was observed in a part of the film, and the appearance was inferior.

A. Base layer laminated surface B. Heat seal surface 1, 3. Layer made of petroleum-derived polyethylene resin 2. Layer made of plant-derived polyethylene resin 4. Base layer

Claims (5)

A sealant film used by laminating it on a base material layer.
A multilayer laminated film composed of one layer or more of a layer made of a petroleum-derived polyethylene resin and one layer or more of a layer made of a plant-derived polyethylene resin.
The outermost layer forming the base layer laminated surface prevents the low molecular weight compound in the plant-derived polyethylene resin from bleeding out to the base layer laminated surface without lowering the slipperiness, and enhances the lamination strength with the base layer. , A layer made of petroleum-derived polyethylene resin,
The petroleum-derived polyethylene-based resin is a petroleum-derived linear low-density polyethylene .
The plant-derived polyethylene-based resin is a resin containing at least one selected from plant-derived high-density polyethylene, plant-derived medium-density polyethylene, plant-derived high-pressure low-density polyethylene, and a mixture thereof.
Alternatively, the plant-derived polyethylene-based resin includes at least one selected from plant-derived high-density polyethylene, plant-derived medium-density polyethylene, plant-derived high-pressure low-density polyethylene, and a mixture thereof, and plant-derived linear low-density polyethylene. It is a resin containing and
The sealant film, wherein the total biomass of the sealant film is 50 to 80%. The sealant film according to claim 1, wherein the sealant film is a two-layer laminated film composed of one layer made of a petroleum-derived polyethylene resin and one layer made of a plant-derived polyethylene resin. A three-layer laminated film composed of two layers of petroleum-derived polyethylene-based resin and one layer of plant-derived polyethylene-based resin.
The outermost layer forming the laminated surface of the base material layer and the outermost layer forming the heat-sealed surface on the opposite side thereof are layers made of petroleum-derived polyethylene resin.
The sealant film according to claim 1, wherein the intermediate layer between them is a layer made of a plant-derived polyethylene-based resin. A packaging material having a base material layer and a layer made of the sealant film according to any one of claims 1 to 3. A packaging bag made of the packaging material according to claim 4.

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