JP7300379B2 - Films and packaging bags using plant-derived polyethylene resin - Google Patents

Description

The present invention relates to a film comprising a polyethylene-based resin composition, and more particularly, at least one plant-derived polyethylene selected from plant-derived high-density polyethylene (HDPE) or plant-derived linear low-density polyethylene (LLDPE). The present invention relates to a film made of a resin-containing polyethylene resin composition, and a packaging bag using this film.

BACKGROUND ART Conventionally, packaging bags typified by pouches used as refills for shampoos, rinses, and the like, and as packaging materials for foodstuffs and the like are composed of a packaging material comprising a sealant film and a base film. In order to deal with environmental problems and save depleted resources such as petroleum, ethylene-α - A packaging bag containing a biodegradable resin containing predetermined amounts of an olefin copolymer and a polymer having an epoxy group is known (for example, Patent Document 1).

JP 2009-155516 A

However, as described above, such a packaging bag includes a biodegradable resin other than petroleum-derived raw materials in the resin composition constituting the packaging bag to reduce the ratio of petroleum-derived raw materials. There was a problem that the processability such as tensile strength, sealing strength, and stiffness was significantly inferior to that of , and productivity could not be improved.

Therefore, an object of the present invention is to use a plant-derived polyethylene resin, which is a renewable resource, as a raw material to save petroleum resources, and to use an environmentally friendly film by reducing carbon dioxide emissions. To provide a packaging bag excellent in processability.

Another object of the present invention is to provide such a film by extrusion molding using a T-die method.

As a result of various studies, the inventors of the present invention have found that a film characterized by the following points and a packaging bag using the same achieve the above objects.
1. A multi-layered sealant film containing at least one layer made of a polyethylene-based resin composition, wherein the polyethylene-based resin composition contains plant-derived high-density polyethylene having a density of 941 to 965 kg/m3, and the plant-derived High-density polyethylene has a biomass degree of 80 to 100% calculated from the measured value of radiocarbon dating C ¹⁴ , and the blending amount of plant-derived polyethylene resin is 5 to 90% by mass with respect to the entire film. The above sealant film, characterized in that the content of the derived polyethylene resin is 10 to 95% by mass.
2. 2. The sealant film according to 1 above, wherein the polyethylene-based resin composition contains plant-derived high-density polyethylene and plant-derived linear low-density polyethylene.
3. The plant-derived linear low-density polyethylene has a density of 910 to 925 kg/m3 and is an ethylene-α-olefin copolymer of plant-derived ethylene and a petroleum-derived comonomer, wherein the petroleum-derived comonomer is butene. -1, hexene-1, or a mixture thereof.
4. A laminated film comprising the sealant film according to any one of 1 to 3 above and a base film laminated together.
5. A packaging bag using a laminated film obtained by laminating the sealant film according to any one of the above 1 to 3 with a base film.
6. 6. The packaging bag according to 5 above, wherein the packaging bag is a standing pouch for refilling.

Hereinafter, the polyethylene-based resin composition containing the plant-derived polyethylene-based resin selected from the plant-derived HDPE or the plant-derived LLDPE is referred to as "the polyethylene-based resin composition of the present invention".

The film of the present invention contains a plant-derived polyethylene resin selected from plant-derived HDPE or plant-derived LLDPE, so that there is no difference in performance from a film made of a petroleum-derived polyethylene resin, and the use of petroleum resources. In addition to reducing the amount, it is possible to suppress carbon dioxide emissions during film production and disposal.

Therefore, it is possible to provide a film made of a polyethylene-based resin with reduced environmental load. Moreover, since it is extruded by the T-die method, it is possible to provide a film having a uniform thickness and at a low cost.

In addition, by using a plant-derived polyethylene resin having an MFR of 2.4 to 8.0 g/10 minutes as the plant-derived polyethylene resin used in the film of the present invention, a homogeneous film can be formed at high speed during extrusion molding by the T-die method. can be manufactured in

In addition, the plant-derived LLDPE used in the film of the present invention has a density of 910 to 925 kg/m ³ , and ethylene obtained from plant-derived ethylene and plant-derived or petroleum-derived butene-1, hexene-1, or a mixture thereof. -By using the α-olefin copolymer, the film has suitable tensile strength, sealing strength and stiffness as a packaging bag, for example, a standing pouch for refilling, and exhibits excellent processability.

In addition, since the film of the present invention has a biomass degree calculated from the measured value of radiocarbon dating ^C14 , the raw material origin of the polyethylene resin constituting the film can be identified by using this biomass degree as an index. The source material can be confirmed from the time of manufacture to the time of disposal.

Therefore, it is possible to provide a film made of a polyethylene-based resin that enables identification of the origin of the raw material.

Furthermore, in one aspect of the present invention, the film of the present invention has a blending amount of the plant-derived polyethylene resin of 5 to 90% by mass and a blending amount of the petroleum-derived polyethylene resin of 10 to 95% by mass with respect to the entire film. % by mass and having the following composition (A) or (B):
(A) A single-layer structure composed of the polyethylene resin composition (B) A multilayer structure having an intermediate layer composed of the polyethylene resin composition, and an outer layer and an inner layer composed of a petroleum-derived polyethylene resin.

Therefore, it is possible to reduce the proportion of petroleum-derived polyethylene resin used in the film, reduce the amount of petroleum resources used, and suppress the amount of carbon dioxide emitted during film production and disposal.

In addition, by using a petroleum-derived polyethylene resin for the inner and outer layers constituting a film such as (B), it is possible to manufacture a film with the characteristics of the existing manufacturing process.

Therefore, it is possible to provide a film made of a polyethylene-based resin that saves petroleum resources and reduces environmental load.

In addition, the laminated film in which the film of the present invention containing a plant-derived polyethylene resin is used as a sealant film and laminated with a base film reduces the amount of petroleum resources used, and carbon dioxide emissions during the production and disposal of the laminated film. amount can be suppressed. Therefore, it is possible to provide a laminated film made of a polyethylene-based resin that saves petroleum resources and reduces environmental load.

In addition, a packaging bag using a laminated film in which the film of the present invention containing a plant-derived polyethylene resin is used as a sealant film and laminated with a base film is obtained by using petroleum-derived polyethylene resin in the laminated film constituting the packaging bag. The usage ratio can be reduced, the amount of petroleum resources used can be reduced, and the amount of carbon dioxide emitted during the manufacture and disposal of packaging bags can be suppressed. Therefore, it is possible to provide a packaging bag made of polyethylene resin that saves petroleum resources and reduces environmental load.

Furthermore, the packaging bag of the present invention may be a standing pouch for refilling, and it is possible to reduce the usage ratio of petroleum-derived polyethylene resin that constitutes a large number of disposable packaging bags on the market, and the amount of petroleum resources used. can be reduced, and carbon dioxide emissions can be suppressed during the manufacture and disposal of packaging bags. Therefore, it is possible to provide a packaging bag made of polyethylene resin that saves petroleum resources and reduces environmental load.

FIG. 2 is a flow chart showing an example of sugarcane-derived polyethylene production. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional side view schematically showing a single-layer film made of the polyethylene-based resin composition of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional side view schematically showing a film having a multi-layer structure having an intermediate layer made of the polyethylene resin composition of the present invention and outer and inner layers made of petroleum-derived polyethylene resin. BRIEF DESCRIPTION OF THE DRAWINGS It is a cross-sectional side view which shows typically an example of the laminated|multilayer film of this invention. 1 is a perspective view showing a standing pouch as an example of a packaging bag formed using the laminated film of the present invention; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings.
Containers exemplified by laminated tubes used for foods and cosmetics, and packaging bags exemplified by standing pouches widely used as refill packaging for shampoos and conditioners are made of laminated films.

Some laminated films are made by laminating a sealant film, which serves as an inner surface of the laminated film, on a base film, and the base film is made of, for example, a polyethylene-based resin. In order to construct a sealant film, for example, linear low-density or high-density polyethylene sandwiching an intermediate layer is used as a laminate.

As described above, polyethylene resins, which are plastic resins, are often used as materials for laminated films. These polyethylene resins are produced using petroleum as a starting material. Low-density polyethylene is obtained by copolymerizing ethylene obtained by refining crude oil and α-olefin, which is a comonomer species, in the gas phase at a high temperature such as 120 ° C. or higher in the presence of a metallocene catalyst. .

The α-olefins are propylene, 1 _- butene, 1-pentene, 1-hexene, 1- Examples include heptene, 1-octene, 1-nonene, 1-decene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene and octadecene.

The metallocene catalyst is not particularly limited, but for example, one type of group selected from a cyclopentadienyl group, a substituted cyclopentadienyl group (substituted cyclopentadienyl group), an indenyl group, and a substituted indenyl group. , a fluorenyl group, and a substituted fluorenyl group having a ligand bridged by a bridge group.

Typical examples thereof include diphenylmethylene (1-cyclopentadienyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene (3-methyl-1-cyclopentadienyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene (1-cyclo pentadienyl)(2,7-dimethyl-9-fluorenyl)zirconium dichloride, diphenylmethylene(1-cyclopentadienyl)(2,7-di-t-butyl-9-fluorenyl)zirconium dichloride, diphenylmethylene (1 -indenyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene(4-phenyl-1-indenyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene(4-phenyl-1-indenyl)(2,7-di-t- A metallocene catalyst containing as a main component a metallocene compound such as a dichloride such as butyl-9-fluorenyl)zirconium dichloride and a dimethyl, diethyl, dihydro, diphenyl or dibenzyl metallocene compound is used.

Further, the metallocene catalyst includes, for example, one type of group selected from a cyclopentadienyl group, a substituted cyclopentadienyl group (substituted cyclopentadienyl group), an indenyl group, and a substituted indenyl group, a fluorenyl group, One type of group selected from substituted fluorenyl groups includes transition metal compounds of Group 4 of the periodic table having a ligand bridged by a crosslinking group. enyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene(3-methyl-1-cyclopentadienyl)(9-fluorenyl)zirconium dichloride, diphenylmethylene(1-cyclopentadienyl)(2,7-dimethyl-9 -fluorenyl)zirconium dichloride, diphenylmethylene(1-cyclopentadienyl)(2,7-di-t-butyl-9-fluorenyl)zirconium dichloride, diphenylmethylene(1-indenyl)(9-fluorenyl)zirconium dichloride, diphenyl Dichlorides such as methylene(4-phenyl-1-indenyl)(9-fluorenyl)zirconium dichloride and diphenylmethylene(4-phenyl-1-indenyl)(2,7-di-t-butyl-9-fluorenyl)zirconium dichloride and a metallocene compound exemplified by the dimethyl, diethyl, dihydro, diphenyl, and dibenzyl compounds of the above metallocene compounds as a main component.

However, as awareness of environmental problems such as global warming due to the increase in carbon dioxide emissions increases, along with the desire to conserve depleted resources such as petroleum, polyethylene resins derived from petroleum as described above are not suitable for petrochemical product manufacturing and disposal. Since a large amount of carbon dioxide immobilized in the petroleum raw material is discharged until reaching the point, the above-mentioned orientation cannot be met.

For this reason, in recent years, the development of technology for manufacturing plastics from plants, which are carbon-neutral and renewable resources, has progressed. of sugar cane as a starting material has been established (Kakko Gijutsu Kenkyukai ed., Convertech 2009.9, pp. 63-67).
Note that carbon neutral means that the amount of carbon dioxide absorbed during plant growth is substantially the same as the amount of carbon dioxide emitted during combustion.

FIG. 1 is a flow chart showing an example of the production of sugarcane-derived polyethylene. FIG. 2 is a cross-sectional side view schematically showing a film made of a polyethylene-based resin composition containing a sugarcane-derived polyethylene-based resin of the present invention.

As shown in FIG. 1, a sugar solution extracted from sugar cane harvested from a field is heated, concentrated and crystallized to separate raw sugar and waste molasses using a centrifuge. The molasses is then diluted with water to a suitable concentration and fermented by yeast to produce ethanol. Then, this bioethanol is heated and ethylene obtained by an intramolecular dehydration reaction in the presence of a catalyst is polymerized by a polymerization catalyst to obtain polyethylene. It has been confirmed that plant-derived ethylene and polyethylene have the same quality as petroleum-derived ethylene and polyethylene.

Therefore, the plant-derived polyethylene-based resin used in the film of the present invention is LLDPE or HDPE produced from plant-derived ethylene as the starting material as described above. These can be produced in the same manner as polyethylene-based resins are produced from petroleum-derived ethylene. That is, plant-derived LLDPE can be produced by copolymerizing plant-derived ethylene and α-olefin by a gas phase polymerization method in the presence of a metallocene catalyst. Further, by polymerizing the plant-derived ethylene at medium pressure or low pressure in the presence of a Ziegler catalyst or a Phillips catalyst, HDPE with few branches can be produced.

In the present invention, by producing a film forming a laminated film constituting a packaging bag using the plant-derived polyethylene resin obtained as described above, the resin composition used for the laminated film has a petroleum-derived By reducing the resin usage ratio, it is possible to save petroleum resources and contribute to the improvement of the environment by reducing the amount of carbon dioxide emissions.
The method for producing this film is not particularly limited, and it can be produced by a conventionally known method.

In the present invention, it is preferable to manufacture by extrusion molding, and it is possible to form a film with a uniform thickness, and high-speed cooling and high-speed film formation are possible, which is excellent in productivity. Manufacturing is particularly preferred.

In the present invention, production of a film by extrusion molding can be carried out, for example, as follows. That is, the resin composition used for the film is dried, and the dried resin composition is placed in a melt extruder heated from the melting point (Tm) of the resin in the resin composition to the melting point +70 ° C. (Tm + 70). feed and melt it.

Next, for example, a film can be produced by extruding the molten resin composition into a sheet using a die such as a T-die, and rapidly solidifying the resulting sheet using a rotating cooling drum or the like. .
As the melt extruder, a single-screw extruder, a twin-screw extruder, a vent extruder, a tandem extruder, or the like can be used depending on the purpose.

In the present invention, the resin composition 1 containing LLDPE or HDPE derived from sugarcane (not limited to sugarcane, but any plant that serves as a raw material for producing a polyethylene-based resin) is used to form a film F1 as shown in FIG. can be

The sugarcane-derived LLDPE has a density of 910 to 925 kg/m ³ and a melt flow rate (MFR) of 2.4 to 8.0 g/10 min. or ethylene-α-olefin copolymers with petroleum-derived comonomers, which can be any α-olefin such as butene-1, hexene-1, or mixtures thereof.

Further, the sugarcane-derived HDPE can have physical properties such as a density of 941 to 965 kg/m ³ and a melt flow rate (MFR) of 2.4 to 8.0 g/10 minutes.

In the physical property evaluation, the density (d, unit: kg/m ³ ) was measured according to JIS K 6760 (1981) using a 1 mm thick sheet obtained by press molding at 150°C. is.

The melt flow rate (MFR, unit: g/10 minutes) was measured at a test temperature of 190°C and a test load of 21.18 N according to JIS K 7210 (1995).

In a preferred embodiment, the polyethylene-based resin composition constituting the film of the present invention contains the plant-derived LLDPE or HDPE in an amount up to 90% by mass, more preferably 5 to 90% by mass. In one aspect of the present invention, the polyethylene resin composition contains 5 to 90% by mass of plant-derived LLDPE or HDPE and 10 to 95% by mass of petroleum-derived polyethylene resin.

Further, as the sugarcane-derived polyethylene resin, a polyethylene resin having a biomass degree of 80 to 100% by radiocarbon dating C ¹⁴ is used.

Here, plant (biomass)-derived resins and petroleum-derived resins have no difference in physical properties such as molecular weight, mechanical properties, and thermal properties. Therefore, biomass degree is generally used to distinguish between them.

In this biomass, the carbon of the petroleum-derived resin does not contain C ¹⁴ (radiocarbon 14, half-life 5730 years), so the concentration of this C ¹⁴ was measured by accelerator mass spectrometry, , is used as an indicator of the content of plant-derived resin. Therefore, in the case of a film using a plant-derived resin, the biomass degree corresponding to the content of the plant-derived resin can be obtained by measuring the biomass degree of the film.

The biomass degree is measured by burning a sample to be measured to generate carbon dioxide, and then reducing the carbon dioxide purified in a vacuum line with hydrogen using iron as a catalyst to generate graphite. Then, this graphite is attached to a C ¹⁴ -AMS dedicated device (manufactured by NEC Corporation) based on a tandem accelerator, and the C ¹⁴ count, the C ¹³ concentration (C ¹³ /C ¹² ), the C ¹⁴ concentration (C ¹⁴ /C ¹² ) is measured and from this measurement the ratio of the C ¹⁴ concentration of the sample carbon to the standard modern carbon is calculated.

In this measurement, oxalic acid (HOXII) provided by the US National Institute of Standards (NIST) was used as a standard sample.

In the present invention, by using a film made of such a resin composition, all of the resins are petroleum-derived resins, and this petroleum-derived polyethylene resin has no difference in performance from petroleum-derived polyethylene resins. By mixing (substituting) with a plant-derived polyethylene-based resin such as , it is possible to suppress carbon dioxide emissions during film production and disposal.

In the present invention, the plant-derived polyethylene-based resin contained in the polyethylene-based resin composition 1 has a comonomer species of butene-1, hexene-1, or a mixture thereof and a density of 910 to 925 kg/m ³ . A plant-derived ethylene-α-olefin copolymer (LLDPE) having a melt flow rate of 2.4 to 8.0 g/10 min, or a density of 941 to 965 kg/m ³ and a melt flow rate of 2.4 to 8. By using .0 g/10 min of HDPE, it is possible to produce a film with the same physical properties as those of petroleum-derived polyethylene resins in the existing film production process. Therefore, the raw material can be changed without impairing the processability of the packaging material.

Furthermore, since the resin composition 1 of the present invention has a biomass degree calculated from the measured value of radiocarbon dating C ¹⁴ , the raw material origin of the polyethylene resin constituting the film can be identified using this biomass degree as an index. , the source material can be confirmed from the time of film production to the time of disposal.

The MFR of the plant-derived LLDPE or plant-derived HDPE constituting the film of the present invention is preferably 2.4 to 8.0 g/10 minutes. The MFR is more preferably 2.5 to 3.0 g/10 minutes in order to exhibit a high degree of biomass and to obtain good tensile strength and seal strength as a packaging bag. In addition, in order to produce a film having a high degree of biomass and a uniform film thickness by extrusion molding by the T-die method at high speed, the MFR is more preferably greater than 4.0, for example, 4 It is about 1 to 8.0 g/10 minutes.

Next, in the present invention, the resin composition 1 described above and the petroleum-derived polyethylene resin 2 described later can be used to form a film as follows.

That is, the following (A) or A film can be constructed in the manner of (B).

First, as the film F1 of (A), as shown in FIG. 2, it is possible to have a single layer structure made of the polyethylene-based resin composition 1 of the present invention. Here, the polyethylene-based resin composition 1 of the present invention contains 5-90% by mass of a plant-derived polyethylene-based resin and 10-95% by mass of a petroleum-derived polyethylene-based resin.

Moreover, as the film F2 of (B), as shown in FIG. 3, it has a multilayer structure having an intermediate layer made of the polyethylene resin composition 1 of the present invention and an outer layer and an inner layer made of a petroleum-derived polyethylene resin. can be done. Here, the polyethylene-based resin composition 1 of the present invention contains the plant-derived polyethylene-based resin in such a concentration that the blending amount of the plant-derived polyethylene-based resin with respect to the entire film is 5 to 90% by mass.

By adopting such a configuration, it is possible to reduce the ratio of petroleum-derived polyethylene-based resin used in the film, and to suppress carbon dioxide emissions during film production and disposal. In addition, by using the petroleum-derived polyethylene-based resin 2 for the inner and outer layers constituting the film F2 as in (B), the film F2 can be manufactured with the characteristics of the existing manufacturing process. These multilayer films can be produced by coextrusion.

Next, in the present invention, a laminate film using the films F1 and F2 can be obtained. FIG. 4 is a cross-sectional side view schematically showing an example of a laminated film, and FIG. 5 is a perspective view showing a standing pouch as an example of a packaging bag formed using the laminated film of the present invention.
As shown in FIG. 4, the laminated film 3 is formed by laminating one of the films F1 to F2 as the sealant film 4 on the base film 5. As shown in FIG.

Examples of the base film 5 include polyethylene-based resin, polypropylene-based resin, cyclic polyolefin-based resin, polystyrene-based resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin). ), polyvinyl chloride resins, fluorine resins, poly(meth)acrylic resins, polycarbonate resins, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as various nylons, polyimide resins, polyamides Various resin films or sheets such as imide resins, polyarylphthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyethersulfone resins, polyurethane resins, acetal resins, cellulose resins, etc. can be done.

With such a configuration, it is possible to reduce the usage ratio of the petroleum-derived polyethylene resin that constitutes each of the films F1 to F2 of the sealant film 4 used for heat sealing. can reduce carbon dioxide emissions during the manufacture and disposal of

Using the laminated film 3 as described above, two side sheets made of the laminated film 3 are arranged with the sealant film 4 surfaces facing each other, and the sealant film 4 is laminated on at least one side of the lower end portion of the laminated film 3. A bottom sheet made of a laminate is folded in the center with the 4 surfaces of the sealant film as the outer surface, and is inserted into the center to have a gusset portion. A semi-circular bottom sheet cut-out is provided and the gusset is heat sealed with a ship bottom-shaped bottom seal including a peripheral edge to form the bottom.

Next, both side edges of the two side sheets on the front and back sides are heat-sealed with the side edge seal portions to form the body portion, and the upper end portion is left to serve as a filling port for the contents, as shown in FIG. A pouch (packaging bag) is formed in the form of a standing pouch. The upper sealing portion provided at the filling port at the upper end portion is to be heat-sealed by, for example, degassing sealing after the contents are filled from this portion. In addition, although not shown, a spout portion provided with a cut line for opening may be formed by a laser at the upper part of the body or the like.

With such a configuration, the usage ratio of the petroleum-derived polyethylene resin in the laminated film 3 that constitutes the packaging bag 6 can be reduced, and along with saving petroleum resources, the manufacturing and disposal of the packaging bag 6 can be reduced. Carbon dioxide emissions can be suppressed. In particular, since this packaging bag 6 is a standing pouch for refilling, it is possible to reduce the usage ratio of petroleum-derived polyethylene resin that constitutes such a disposable packaging bag and to greatly suppress carbon dioxide emissions. can.

In addition to the packaging bag 6 exemplified by the above-described standing pouch, using the films F1 to F2 made of the polyethylene resin composition 1 of the present invention and the laminated film 3 using these films F1 to F2, It can be used for containers such as laminated tubes, paper containers for liquids, container lids, and container labels. can be reduced, and the amount of carbon dioxide emissions can be greatly suppressed.

Furthermore, the present invention can also be configured as follows.
1. A single-layer film made of a polyethylene resin composition, or a multilayer film containing at least one layer made of the polyethylene resin composition, extruded by a T-die method, The above film, wherein the polyethylene-based resin composition contains a plant-derived polyethylene-based resin selected from plant-derived HDPE and plant-derived LLDPE.
2. 2. The film according to 1 above, wherein the plant-derived polyethylene resin has a melt flow rate (MFR) of 2.4 to 8.0 g/10 minutes.
3. The plant-derived LLDPE has a density of 910 to 925 kg/m ³ and is an ethylene-α-olefin copolymer of plant-derived ethylene and petroleum-derived comonomers, wherein the petroleum-derived comonomers are butene-1 and hexene. -1, or a mixture thereof.
4. 4. The film according to any one of the above 1 to 3, characterized in that it has a biomass degree calculated from radiocarbon dating C ¹⁴ measurements.
5. With respect to the entire film, the blending amount of the plant-derived polyethylene resin is 5 to 90% by mass, and the blending amount of the petroleum-derived polyethylene resin is 10 to 95% by mass, and the following (A) or (B) 5. The film according to any one of 1 to 4 above, characterized in that it has a structure.
(A) Single-layer structure comprising the polyethylene resin composition (B) Multilayer structure comprising an intermediate layer comprising the polyethylene resin composition and an outer layer and an inner layer comprising a petroleum-derived polyethylene resin6. A laminated film comprising the film according to any one of 1 to 5 above as a sealant film and laminated with a base film.
7. A packaging bag using a laminated film obtained by laminating the film according to any one of the above 1 to 5 with a base film as a sealant film.
8. 8. The packaging bag according to 7 above, wherein the packaging bag is a standing pouch for refilling.

Next, examples of films constructed using the polyethylene-based resin composition 1 of the present invention will be described.

[Example 1]
Using an extruder with a screw diameter of 30 mmφ, Braskem C4LL-LL318 (d = 0.918, MFR = 2.7 g / 10 minutes), which is a sugarcane-derived LLDPE, is melt-kneaded at 200 ° C. to obtain the polyethylene resin of the present invention. A composition was obtained.

Then, the resin composition was molded using a T-die-cast film forming machine under processing conditions of an extrusion temperature of 220° C. and a rotation speed of 45 rpm, thereby forming a film F1 having a thickness of 120 μm and shown in FIG. When its biomass degree was measured, it was about 88%. In addition, this film had a uniform thickness and a beautiful appearance. The comonomer species butene-1 (C4) contained in sugarcane-derived LLDPE is petroleum-derived, and its content is 1 to 15 mol % (the same shall apply hereinafter).

On the other hand, as Comparative Example 1, using 100% C6LL-Evolue SP2040 (d = 0.918, MFR = 3.8 g / 10 minutes) manufactured by Prime Polymer Co., Ltd. derived from petrochemicals, in the same manner as in Example 1, The mixture was melt-kneaded at 200° C. and formed into a film having a thickness of 120 μm under processing conditions of an extrusion temperature of 220° C. and a rotation speed of 45 rpm. When the biomass degree was measured, it was 0%.

The resin compositions of Example 1 and Comparative Example 1 were subjected to the following physical property evaluation tests, and the obtained results are described below.

As described above, the film of the present invention made of a polyethylene-based resin composition containing plant-derived LLDPE has physical properties equivalent to those of a film made of only petrochemical-derived LLDPE, and exhibits good tensile strength, manufacturing processability, and seal strength. rice field.

[Test method]
The tensile breaking strength (elongation) was measured using a Tensilon universal testing machine with reference to JIS-Z1702 at a test speed of 500 mm/min. N=3 JIS-K7127 test piece type 5 (dumbbell piece: minimum parallel width 6 mm, distance between chucks 80 mm).
The waist was measured using a loop stiffness tester with a loop length of 60 mm, a sample width of 15 mm, N=3, and a crushing distance of 17 mm (scale 3).
The seal strength was evaluated by using a heat seal tester TP-701S, placing a 12 μm piece of PET on an evaluation sample, sealing it at 180° C.×1 kgf/cm ² ×1.0 seconds, cutting out a strip-shaped sample with a width of 15 mm, and performing a Tensilon universal test. It was measured on a machine at a test speed of 300 mm/min.N=3.

[Example 2]
In the same manner as in Example 1, using an extruder with a screw diameter of 30 mmφ, Braskem C4LL-LL318 (d = 0.918, MFR = 2.7 g / 10 minutes), which is LLDPE derived from sugarcane, and C6LL- manufactured by Prime Polymer Co., Ltd. Evolue SP2040 (d=0.918, MFR=3.8 g/10 min) was kneaded and melted at a mass ratio of 7:3 at 200° C. to obtain the polyethylene resin composition of the present invention. Then, the resin composition was molded using a T-die-cast film forming machine under processing conditions of an extrusion temperature of 220° C. and a rotation speed of 45 rpm, thereby forming a film F1 having a thickness of 120 μm and shown in FIG.
When its biomass degree was measured, it was about 59%. In addition, this film had a uniform thickness and a beautiful appearance, and was excellent in tensile strength, processability, and sealing strength.

[Example 3]
In the same manner as in Example 1, an extruder with a screw diameter of 30 mmφ was used to knead and melt Braskem SHC7260 (d = 0.959, MFR = 7.2 g/10 min), which is a sugarcane-derived HDPE, at 200 ° C. was obtained. Then, the resin composition was molded using a T-die-cast film forming machine under processing conditions of an extrusion temperature of 220° C. and a rotation speed of 45 rpm, thereby forming a film F1 having a thickness of 120 μm and shown in FIG. When its biomass degree was measured, it was about 95%. In addition, this film had a uniform thickness and a beautiful appearance, and was excellent in tensile strength, processability, and sealing strength.

[Example 4]
In the same manner as in Example 1, using an extruder with a screw diameter of 30 mmφ, 50% by mass of Braskem C4LL-LL118 (d = 0.916, MFR = 1.0 g / 10 min), which is a sugarcane-derived LLDPE, and petroleum-derived 50 mass % of Ube Maruzen polyethylene LDPE-F120N (d=0.920, MFR=1.2 g/10 min) which is LLDPE was melt-kneaded at 200° C. to obtain the polyethylene resin composition of the present invention.

Then, the resin composition was formed into a film F1 having a thickness of 130 μm and shown in FIG. When the biomass degree was measured, it was about 44%. In addition, this film had a uniform thickness and a beautiful appearance, and was excellent in tensile strength, processability, and sealing strength.

[Example 5]
As resins for the first layer (inner layer) and the third layer (outer layer), Mitsui Chemicals C6LL-Evolue SP2020 (d = 0.916, MFR = 2.3 g/10 min) was used using an extruder with a screw diameter of 30 mm. The mixture was melt-kneaded at 200° C. to prepare a petroleum-derived polyethylene resin. Similarly, as a resin for the second layer (intermediate layer), an extruder with a screw diameter of 30 mmφ was used to extruder 200% of Braskem C4LL-LL118 (d = 0.916, MFR = 1.0 g/10 min), which is LLDPE derived from sugarcane. C. to obtain the polyethylene resin composition of the present invention. The layer thickness ratio of the first layer:second layer:third layer was set to 1:1:1. Then, the resin composition was formed into a film F2 having a thickness of 130 μm and shown in FIG.
When the biomass degree was measured, it was about 29%. In addition, this film had a uniform thickness and a beautiful appearance, and was excellent in tensile strength, processability, and sealing strength.

[Example 6]
As the resin composition for the first layer (inner layer) and the third layer (outer layer), Mitsui Chemicals C6LL-Evolue SP2020 (d = 0.916, MFR = 2.3 g / 10 minutes) using an extruder with a screw diameter of 30 mm ) was melt-kneaded at 200° C. to prepare a petroleum-derived polyethylene resin. Similarly, as the resin composition for the second layer (intermediate layer), using an extruder with a screw diameter of 30 mmφ, Braskem C4LL-LL118 (d = 0.916, MFR = 1.0 g / 10 minutes), which is LLDPE derived from sugarcane. 50% by mass and 50% by mass of Ube Maruzen polyethylene LDPE-F120N (d = 0.920, MFR = 1.2 g/10 min) were melt-kneaded at 200 ° C. to obtain the polyethylene resin composition of the present invention. . The layer thickness ratio of the first layer:second layer:third layer was 1:2:1.

Then, the resin composition was formed into a film F2 having a thickness of 130 μm and shown in FIG. When this biomass degree was measured, it was about 22%. In addition, this film had a uniform thickness and a beautiful appearance, and was excellent in tensile strength, processability, and sealing strength.

[Example 7]
A biaxially oriented nylon film (ONy, Toyobo Harden N-1102) as the base film 5 with a thickness of 25 μm for the outer layer and the film of Example 1 are used, and a two-liquid curing urethane adhesive is used, About 4 g/m ² of the adhesive was applied to the ONy surface, and the corona-treated surface of polyethylene was laminated by a dry lamination method to obtain a laminated film 3 having a two-layer structure shown in FIG.
When this biomass degree was measured, it was about 70%.

Then, using this laminated film 3, a refill standing pouch (packaging bag 6) with a spout portion provided with a cut line for opening with a laser is prepared, the contents are put into this refill standing pouch, and the opening is was observed for leakage of the contents, overturning, buckling, and breaking of the trunk, but none were observed. Furthermore, a drop test from a height of 1 m was performed five times, but no bag breakage or leakage was observed.

[Example 8]
The outer layer is a biaxially oriented nylon film (ONy, Toyobo Harden N-1102) having a thickness of 25 μm as the base film 5, and the intermediate layer is a 12 μm thick VMPET (a metal vapor deposition film in which aluminum is vapor-deposited on one side, A polyethylene terephthalate film in which aluminum is vapor-deposited) is laminated with the aluminum vapor-deposited surface, and about 4 g/m ² of a two-component curing type urethane adhesive is applied to the polyethylene terephthalate surface of VMPET. The corona-treated surface was laminated by a dry lamination method to obtain a laminated film having a three-layer structure.

Then, using this laminated film, a standing pouch for refilling (packaging bag 6) with a spout provided with a cut line for opening by a laser was produced.
When the biomass degree was measured, it was about 62%.
Regarding the prepared standing pouch for refilling, which was filled with the contents and the opening was sealed, leakage of the contents, overturning, buckling, and breakage of the body were observed, but none were observed. Furthermore, a drop test from a height of 1 m was performed 5 times, but no bag breakage or leakage was observed.

[Example 9]
Only the bottom material in the standing refill pouch with a spout part of Example 8 was made using a petroleum-derived film made of stretched polyamide (ONY) / LLDPE (linear low-density polyethylene). Regarding the case where the contents were put in and the opening was sealed, leakage of the contents, overturning, buckling, and breakage of the body were observed, but none were observed.
Furthermore, a drop test from a height of 1 m was performed 5 times, but no bag breakage or leakage was observed.
Therefore, for the bottom material of the standing pouch of the present invention, either a laminated film containing the same plant-derived material as the body or a petroleum-derived film may be used.

As described in detail above, the film made of polyethylene-based resin of the present invention is made of resin composition 1 containing plant-derived LLDPE or HDPE obtained by gas phase polymerization. Also, these films are used as sealant films and laminated with base films to form laminated films, and packaging bags are made of this laminated film.

The present invention can be applied to any product using polyethylene resin, such as a film made of polyethylene resin and a packaging bag made of this film.

1 polyethylene-based resin composition of the present invention 2 petroleum-derived polyethylene-based resin 3 laminated film 4 sealant film 5 base film 6 packaging bag 7, 8 side sheet 9 bottom sheet F1 to F2 film

Claims (5)

A multi-layered sealant film (excluding a stretched film) containing at least one layer made of a polyethylene resin composition,
The multilayered sealant film has an intermediate layer made of the polyethylene-based resin composition, and an outer layer and an inner layer made of a petroleum-derived polyethylene-based resin,
The polyethylene-based resin composition contains plant-derived high-density polyethylene having a density of 941 to 965 kg/m ³ ,
The plant-derived high-density polyethylene has a biomass degree of 80 to 100% calculated from the measured value of radiocarbon dating C14,
The plant-derived high-density polyethylene has a melt flow rate of 4.1 to 8.0 g/10 minutes,
The polyethylene-based resin composition is a composition containing 5 to 90% by mass of two resins, a plant-derived high-density polyethylene and a plant-derived linear low-density polyethylene, and 10 to 95% by mass of a petroleum-derived polyethylene resin. and
The above sealant film, wherein the blending amount of the plant-derived polyethylene resin is 5 to 90% by mass, and the blending amount of the petroleum-derived polyethylene resin is 10 to 95% by mass, based on the entire film. The plant-derived linear low-density polyethylene has a density of 910 to 925 kg/m ³ and is an ethylene-α-olefin copolymer of plant-derived ethylene and a petroleum-derived comonomer, wherein the petroleum-derived comonomer is A sealant film according to claim 1, characterized in that it is butene-1, hexene-1, or a mixture thereof. A laminated film comprising the sealant film according to claim 1 or 2 laminated with a base film. A packaging bag using a laminated film obtained by laminating the sealant film according to claim 1 or 2 with a base film. 5. The packaging bag according to claim 4, wherein the packaging bag is a standing pouch for refilling.

Images