JP6699710B2 - Sealant film for packaging material using plant-derived polyethylene, laminated film for packaging material, and packaging bag - Google Patents

Description

  The present invention relates to a film made of a polyethylene-based resin, and more specifically to a sealant film for a packaging material, a laminated film for a packaging material, in which the polyethylene-based resin contains a plant-derived polyethylene-based resin, and a packaging bag using these films.

  Conventionally, for example, packaging bags typified by refills such as shampoos and rinses, and pouches used as packaging materials for foods, etc., are composed of a packaging material composed of a sealant film and a base film, which may cause environmental problems or petroleum. To reduce the consumption of depleted resources and reduce the amount of these petroleum resources used in packaging materials, ethylene-α-olefin copolymers and polymers containing epoxy groups are added to polylactic acid-based resins as carbon-neutral materials. There is a packaging bag (for example, Patent Document 1) containing a biodegradable resin composition containing a predetermined amount of each.

JP, 2009-155516, A

However, in such a packaging bag, as described above, although the resin composition constituting the packaging bag contains a biodegradable resin other than the petroleum-derived raw material to reduce the proportion of the petroleum-derived raw material, a petroleum-based resin is used. There was a problem that the processability such as tear strength and heat seal strength was remarkably inferior and the productivity could not be improved as compared with.
Therefore, an object of the present invention is to use a plant-derived polyethylene-based resin, which is a renewable resource, as a raw material to enable the saving of petroleum resources, and at the same time, to reduce the amount of carbon dioxide emissions, which is an environmentally friendly sealant film for packaging materials. Another object of the present invention is to provide a laminated film for packaging material, and a packaging bag using these films and having excellent processability.

  Therefore, the sealant film for a packaging material according to the invention of claim 1 is a film made of a polyethylene resin, which is directly obtained by a gas phase polymerization method of plant-derived ethylene and petroleum-derived α-olefin. Single-layer constitution in which a resin composition containing 5 to 90% by weight of a chain-shaped low-density plant-derived polyethylene resin and 10 to 95% by weight of a petroleum-derived polyethylene resin and a petroleum-derived polyethylene resin are mixed. Is used as a heat-sealable film.

The sealant film for packaging material according to claim 2 is the film according to claim 1, wherein the polyethylene-based resin has ethylene-α having a biomass degree calculated from a measured value of radiocarbon dating ¹⁴ C. -It is characterized by being an olefin copolymer.

The invention according to claim 3 is the sealant film for a packaging material according to claim 1 or 2, wherein the α-olefin is butene-1 or hexene-1 or a mixture thereof, and the density is 0.910 to 0. The melt flow rate is 925 g/cm ³ , and the melt flow rate is 0.5 to 4.0 g/10 min.

  A laminated film for packaging material according to a fourth aspect of the present invention is characterized in that the sealant film for packaging material according to any one of the first to third aspects is laminated with a base film.

  A packaging bag according to a fifth aspect of the present invention is characterized by using the laminated film for packaging material according to the fourth aspect.

  According to the invention described in claim 1, a film made of a polyethylene resin, which is a linear low-density plant-derived polyethylene obtained by a gas phase polymerization method of plant-derived ethylene and petroleum-derived α-olefin A heat-sealable film having a single layer structure in which a resin composition containing 5 to 90% by weight of a petroleum-derived polyethylene resin and 10 to 95% by weight of a petroleum-derived polyethylene-based resin and a petroleum-derived polyethylene-based resin are mixed. Therefore, the composition of the sealant film for a packaging material made of polyethylene resin depends on the resin composition derived from petroleum, and the polyethylene resin derived from petroleum differs in performance from the polyethylene resin derived from petroleum. By replacing (replacement) with plant-derived polyethylene-based resins such as sugar-cane, which is carbon-neutral, the amount of petroleum resources used is reduced, and carbon dioxide emissions are reduced during the production and disposal of sealant films for packaging materials. be able to. Therefore, it is possible to provide a sealant film for a packaging material, which is made of polyethylene resin and has a reduced environmental load. Furthermore, the use ratio of petroleum-derived polyethylene-based resins that form the sealant film for packaging materials can be reduced. Therefore, it is possible to provide a sealant film for a packaging material made of a polyethylene-based resin, which saves petroleum resources and reduces environmental load.

According to the invention of claim 2, the polyethylene resin is an ethylene-α-olefin copolymer having a biomass degree calculated from the measured value of radiocarbon dating ¹⁴ C, so that the sealant film for a packaging material is The origin of the raw material of the constituent polyethylene resin can be identified by using this biomass degree as an index, and the originating raw material can be confirmed from the time of manufacturing the sealant film for packaging material to the time of disposal. Therefore, it is possible to provide a sealant film for a packaging material, which is made of a polyethylene resin and is capable of identifying the origin of the raw material.

According to the invention of claim 3, the α-olefin is butene-1 or hexene-1 or a mixture thereof, the density is 0.910 to 0.925 g/cm ³ , and the melt flow rate is 0.5 to 4. Since it has a physical property of 0.0 g/10 min, there is no difference in physical properties from the polyethylene-based resin derived from petroleum, so existing film manufacturing processes can be used, and the raw materials can be switched without impairing the processability of the packaging material. You can Therefore, it is possible to provide a sealant film for a packaging material, which is made of polyethylene resin and is excellent in the reduction of environmental load and the production efficiency.

  According to the invention described in claim 4, a packaging in which a sealant film for a packaging material (described in any one of claims 1 to 3) made of a polyethylene resin including a plant-derived polyethylene resin is laminated with a base film. Since it is a laminated film for materials, even in the sealant film used for heat sealing, it is possible to reduce the petroleum-derived usage ratio of the polyethylene resin constituting the film that is the sealant film, and reduce the amount of petroleum resources used. At the same time, it is possible to suppress the carbon dioxide emission amount at the time of manufacturing and discarding the laminated film for packaging material. Therefore, it is possible to provide a laminated film for a packaging material made of a polyethylene-based resin, which saves petroleum resources and reduces environmental load.

  According to the invention of claim 5, a laminated film for a packaging material, in which a film made of a polyethylene-based resin containing a plant-derived polyethylene-based resin (any one of claims 1 to 3) is laminated with a base film. Since it is a packaging bag formed by using (claim 4), it is possible to reduce the use ratio of petroleum-derived polyethylene resin in the laminated film for packaging material that constitutes the packaging bag, and to reduce the amount of petroleum resources used. It is possible to reduce the amount of carbon dioxide and reduce the amount of carbon dioxide emission at the time of manufacturing and discarding the packaging bag. Therefore, it is possible to provide a packaging bag made of polyethylene resin, which saves petroleum resources and reduces environmental load.

  Furthermore, it is possible to reduce the usage rate of polyethylene-based resin, which is used as a disposable bag many times in the world, that is derived from petroleum, and reduce the amount of petroleum resources used, as well as carbon dioxide emissions during the manufacture and disposal of packaging bags. The amount can be suppressed.

It is a flow figure showing an example of polyethylene manufacture from sugar cane. It is a cross-sectional side view which shows typically the film which consists of the linear low density polyethylene-type resin derived from the sugar cane of this invention. It is a cross-sectional side view which shows typically the film of the single layer structure which mixed the resin composition of this invention and the polyethylene-type resin derived from petroleum. It is a cross-sectional side view which shows typically the film which has a multilayer structure which made the intermediate|middle layer of this invention the resin composition. FIG. 1 is a cross-sectional side view schematically showing a film having a multilayer structure in which an intermediate layer of the present invention is a layer in which a resin composition and a petroleum-derived polyethylene resin are mixed. It is a cross-sectional side view which shows an example of the laminated film of this invention typically. It is a perspective view which shows the standing pouch as an example of the packaging bag formed using the laminated film of this invention.

  Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. These containers and packaging bags are laminated on containers such as laminated tubes used for foods and cosmetics, and on packaging bags such as standing pouches that are widely used as refill packaging materials for shampoos and conditioners. It is made of film.

  In this laminated film, there is one in which a sealant film used as a heat-sealing material on the inner surface of the laminated film is laminated on a base film, and as the material of the base film, for example, a polyethylene resin is used, and the sealant film is used. As the material, a linear low-density polyethylene-based resin is used as a laminate, for example, with an intermediate layer sandwiched therebetween.

As described above, a polyethylene resin, which is a plastic resin, is often used as the material for the laminated film. Conventionally, this polyethylene resin is produced by petrochemical origin using petroleum as a starting material. The linear low-density polyethylene-based resin described above contains ethylene obtained by refining crude oil and the like, and α-olefin as a comonomer species in the presence of a metallocene catalyst in a gas phase at a high temperature such as 120° C. or higher. Are copolymerized with. The α-olefin is represented by the general formula R-CH=CH ₂ (wherein R is an alkyl group having 1 or more carbon atoms), propylene, 1-butene, 1-pentene, 1-hexene, 1- Examples thereof include heptene, 1-octene, 1-nonene, 1-decene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-pentene, octadecene and the like. Further, the metallocene catalyst is not particularly limited, but for example, one group selected from a cyclopentadienyl group, a cyclopentadienyl group having a substituent (substituted cyclopentadienyl group), an indenyl group, and a substituted indenyl group. , A fluorenyl group, a substituted fluorenyl group, and one type of group having a ligand bridged by a bridging group can be mentioned a transition metal compound of Group 4 of the periodic table, and diphenylmethylene (1 -Cyclopentadienyl)(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, diphenylmethylene (4-phenyl-1-indenyl) (9-fluorenyl) zirconium dichloride, diphenylmethylene (4-phenyl-1-indenyl) (2,7-di-t-butyl-9-fluorenyl) zirconium dichloride A metallocene catalyst containing, as a main component, a metallocene compound exemplifying a dimethyl derivative, a diethyl derivative, a dihydro derivative, a diphenyl derivative, a dibenzyl derivative of the above metallocene compound and the like is used. The metallocene catalyst includes, for example, a cyclopentadienyl group, a cyclopentadienyl group having a substituent (a substituted cyclopentadienyl group), an indenyl group, a substituted indenyl group, and a fluorenyl group, One type of group selected from the substituted fluorenyl group may be a transition metal compound of Group 4 of the periodic table having a ligand bridged by a bridging group, and a typical example thereof is diphenylmethylene (1-cyclopentadiene). (Phenyl)(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 Dichloro compounds 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 exemplifying a dimethyl form, a diethyl form, a dihydro form, a diphenyl form, a dibenzyl form of the above metallocene compound as a main component.

  However, as the awareness of environmental issues such as global warming due to an increase in carbon dioxide emissions increases along with the intention to save depleted resources such as petroleum, polyethylene-based resins derived from petroleum, as described above, are used in the production of petrochemical products and in the disposal. In the meantime, a large amount of fixed carbon dioxide contained in the petroleum raw material will be discharged, so that the above intention cannot be met.

  Based on these problems, in recent years, the development of technology for producing plastics from plants, which are carbon neutral and renewable resources, has been progressing. Among them, polyethylene, which is most produced among plastics, is The technology for producing sugarcane of the system as a starting material has been established. (Convertec 2009.9, P63-67, edited by Processing Technology Research Group) In addition, carbon neutral means that the amount of carbon dioxide absorbed during plant growth and the amount of carbon dioxide emission during combustion are approximately the same. Say.

  FIG. 1 is a flow chart showing an example of production of polyethylene derived from sugar cane, and FIG. 2 is a cross-sectional side view schematically showing a film made of a linear low-density polyethylene-based resin derived from sugar cane of the present invention.

  As shown in FIG. 1, the sugar solution taken out from the sugar cane cut from the field is heated and concentrated to separate the crystallized crude sugar from the waste sugar dense by a centrifuge. The spent sugar concentrate is then diluted with water to an appropriate concentration and fermented with yeast to produce ethanol. Then, by heating this bioethanol, ethylene obtained by the intramolecular dehydration reaction in the presence of a catalyst is polymerized by a polymerization catalyst to obtain polyethylene. It should be noted that plant-derived ethylene and polyethylene have been confirmed to be equivalent in quality to petroleum-derived ethylene and polyethylene.

  Therefore, the linear low-density polyethylene-based resin used in the film of the present invention is produced from ethylene derived from plant-derived starting materials as described above. It can be obtained by copolymerizing plant-derived ethylene and α-olefin by a gas phase polymerization method in the presence of a metallocene catalyst, as in the case of producing a chain low density polyethylene resin.

  In the present invention, it is used as a laminated film by producing a film forming a laminated film that constitutes a container or a packaging bag using the plant-derived linear low-density polyethylene-based resin obtained as described above. In resin compositions (such as linear low-density polyethylene-based resins), the usage ratio of petroleum-derived resin compositions can be reduced to save petroleum resources and contribute to the environment improvement by reducing carbon dioxide emissions. To do.

  In the present application, a linear low-density polyethylene system derived from sugar cane obtained by the gas phase polymerization method (not limited to sugar cane and any other plant that is a raw material for producing a linear low-density polyethylene resin) may be used. The resin composition 1 made of a resin can be used to form a film F1 as shown in FIG.

Moreover, the linear low-density polyethylene-based resin derived from sugar cane, like the linear low-density polyethylene-based resin derived from petroleum, has a comonomer species of butene-1 (C4) and a density of 0.910 to 0.925 g. /Cm ³ , and the melt flow rate (MFR) is in the range of 0.5 to 4.0 g/10 minutes, more preferably 0.7 to 3.5 g/10 minutes. An α-olefin copolymer is used. The resin composition comprising such a linear low-density polyethylene-based resin derived from sugar cane is contained in an appropriate proportion with respect to the linear low-density polyethylene-based resin derived from petroleum as an upper limit of 90% by weight.

In the above physical property evaluation, the density (d, unit: g/cm ³ ) was measured according to JIS K 6760 (1981) using a sheet having a thickness of 1 mm obtained by press molding at 150°C. Is. Further, the melt flow rate (MFR, unit: g/10 minutes) is measured according to JIS K 7210 (1995) under a test temperature of 190° C. and a test load of 21.18 N.

Furthermore, the above-mentioned ethylene-α-olefin copolymer having a biomass degree of 80 to 100% by radiocarbon dating ¹⁴ C is used for the sugarcane-derived linear low-density polyethylene-based resin.

Here, the plant (biomass)-derived and petroleum-derived resin compositions have no difference in physical properties such as molecular weight, mechanical properties, and thermal properties. Therefore, the biomass degree is generally used to distinguish them. At this biomass level, since carbon of the resin composition derived from petroleum does not contain ¹⁴ C (radiocarbon 14, half-life of 5730 years), the concentration of this ¹⁴ C was measured by accelerator mass spectrometry, and In the composition, it is used as an index of the content ratio of the plant-derived resin composition. Therefore, in the case of a film using a plant-derived resin composition, when the biomass degree of the film is measured, the biomass degree according to the content of the plant-derived resin composition is generated.

In the measurement of the biomass degree, a sample to be measured is burned to generate carbon dioxide, and carbon dioxide purified in a vacuum line is reduced with hydrogen using iron as a catalyst to generate graphite. Then, the graphite was attached to the tandem accelerator ¹⁴ C-AMS-only apparatus which is based on (manufactured by NEC ^{Corp.), 14} C ^counts, the ¹³ C concentration ^{(13 C} / 12 ^C), the ¹⁴ C concentration ⁽¹⁴ was measured for ^C / 12 ^C), it calculates the ratio of the ^{14 C} concentration of the sample carbon to standard modern carbon from the measurement value. In this measurement, oxalic acid (HOxII) provided by the National Bureau of Standards (NIST) was used as a standard sample.

  In the present application, by forming a film composed of such a resin composition, from the state of relying on the petroleum-derived resin composition, the petroleum-derived polyethylene-based resin, the petroleum-derived polyethylene-based resin and performance By mixing (substituting) a plant-based polyethylene resin such as sugar cane, which makes no difference, it is possible to suppress carbon dioxide emissions during film production and disposal.

Further, the resin composition 1 of the present invention has ethylene-α- as a comonomer species of butene-1, a density of 0.910 to 0.920 g/cm ³ , and a melt flow rate of 0.70 to 1.30 g/10 min. Since it is an olefin copolymer, it has no physical difference from the polyethylene-based resin derived from petroleum, so that the existing film manufacturing process can be used and the raw material can be switched without impairing the processability of the packaging material.

Furthermore, since the resin composition 1 of the present invention is an ethylene-α-olefin copolymer having a biomass degree calculated from the measured value of radiocarbon dating ¹⁴ C, it is derived from the raw material of the polyethylene resin constituting the film. The biomass degree can be used as an index for identification, and the origin material from the time the film is manufactured to the time it is discarded can be confirmed.

  Next, in the present application, the resin composition 1 described above and the petroleum-derived polyethylene-based resin 2 described below can be formed into the following film. FIG. 3 is a cross-sectional side view schematically showing a film having a single-layer structure in which a resin composition and a polyethylene resin derived from petroleum are mixed, and FIG. 4 is a film having a multilayer structure in which an intermediate layer is a resin composition. FIG. 5 is a cross-sectional side view schematically showing a film having a multilayer structure in which the intermediate layer is a layer in which the resin composition and the petroleum-derived polyethylene resin are mixed.

  In this case, 5 to 90% by weight of the resin composition 1 and 10 to 95% by weight of the petroleum-derived polyethylene resin 2 are formed into a film in the following procedure (A), (B) or (C). Configured. First, as the film F2 of (A), as shown in FIG. 3, it is possible to have a single-layer structure in which the resin composition 1 and the polyethylene-based resin 2 derived from petroleum are mixed.

  Further, as the film F3 of (B), as shown in FIG. 4, it is possible to have a multilayer structure in which the intermediate layer is the resin composition 1 and the outer layer and the inner layer are the petroleum-derived polyethylene resin 2.

  Further, as the film F4 of (C), as shown in FIG. 5, the intermediate layer is a layer obtained by mixing the resin composition 1 and the petroleum-derived polyethylene resin 2, and the outer layer and the inner layer are the petroleum-derived polyethylene resin 2. It is also possible to have a multilayer structure.

  With such a configuration, the use ratio of the polyethylene-based resin 2 forming the films F2 to F4 derived from petroleum can be reduced, and the carbon dioxide emission amount at the time of film production and disposal can be suppressed. In addition, by using the petroleum-derived polyethylene-based resin 2 for the inner and outer layers constituting the films F3 to F4 such as (B) or (C), the films F3 to F4 can be manufactured with the characteristics that the existing manufacturing process has. You can

  Next, in the present application, a laminated film using the films F1 to F4 can be formed. FIG. 6 is a sectional side view schematically showing an example of a laminated film, and FIG. 7 is a perspective view showing a standing pouch as an example of a packaging bag formed using the laminated film of the present invention.

  First, as shown in FIG. 6, the laminated film 3 is laminated with the base film 5 using any of the films F1 to F4 as the sealant film 4.

  Examples of the base film 5 include polyethylene resin, polypropylene resin, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin). ), polyvinyl chloride resin, fluorine resin, poly(meth)acrylic resin, polycarbonate resin, polyester resin such as polyethylene terephthalate and polyethylene naphthalate, polyamide resin such as various nylons, polyimide resin, polyamide Use various resin films or sheets such as imide resin, polyaryl phthalate resin, silicone resin, polysulfone resin, polyphenylene sulfide resin, polyether sulfone resin, polyurethane resin, acetal resin, cellulose resin, etc. You can

  With such a configuration, even in the sealant film 4 used for heat sealing, the petroleum-derived use ratio of the polyethylene-based resin forming each of the films F1 to F4 that is the sealant film 4 can be reduced, It is possible to save resources and suppress the carbon dioxide emissions at the time of manufacturing and discarding the laminated film 3.

  Using the laminated film 3 as described above, the sealant film 4 faces of the two side sheets 7 and 8 made of the laminated film 3 are arranged to face each other, and the sealant film 4 is provided on at least one face at the lower end of the laminated film 3. A bottom sheet 9 composed of laminated laminates is formed into a form having a gusset portion by mountain-folding the sealant film 4 as an outer surface and inserting the bottom sheet on both sides. In the vicinity, a cutout portion of the bottom sheet having a substantially semicircular shape is provided, and the gusset portion is heat-sealed by a bottom-bottomed sealing portion including a peripheral portion to form a bottom portion.

  Next, both side edge portions of the two side sheets 7 and 8 on the front and back sides are heat-sealed by the side edge seal portions to form a body portion, and the upper end portion is left to be a filling port for contents. A pouch (packaging bag 6) manufactured into a standing pouch type as shown is formed. Then, the upper seal portion provided in the filling port at the upper end portion is filled with the contents from this portion and then heat-sealed by, for example, a deaeration seal or the like for sealing. Although not shown, a spout may be formed in the upper portion of the body part or the like by using a laser to provide a cut line for opening.

  With such a configuration, it is possible to reduce the use ratio of the polyethylene-based resin derived from petroleum in the laminated film 3 that constitutes the packaging bag 6, save petroleum resources, and reduce the amount of time when the packaging bag 6 is manufactured and discarded. 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 use ratio of petroleum-derived polyethylene-based resin that constitutes such a packaging bag, which is widely used as a disposable bag, and to greatly reduce carbon dioxide emissions. You can

  In addition to the packaging bag 6 exemplified by the above-mentioned standing pouch, polyethylene films are used by using the films F1 to F4 made of the resin composition 1 of the present invention and the laminated film 3 using these films F1 to F4. A container including a laminated tube, a liquid paper container or the like for containing contents such as food and drink, cosmetics, chemicals, and miscellaneous goods, a lid material of the container, or a container, which is composed of the resin composition 1 using a resin It is possible to configure such a label, and to further reduce the use ratio derived from petroleum and to greatly reduce carbon dioxide emissions.

  Next, an example of a film constituted by using the plant-derived polyethylene resin (resin composition 1) of the present invention will be described.

  Using a screw diameter 30 mmφ extruder, 200 parts of C4LL-LL118 (d=0.916, MFR=1.0 g/10 min), which is a straight-chain low-density polyethylene-based resin (resin composition 1) derived from sugar cane, manufactured by Braschem Co., Ltd. Melt kneading was performed at 0° C. to obtain a resin composition. Then, the resin composition is molded under a processing condition of an extrusion temperature of 200° C. and a rotation speed of 60 rpm by a top-blown air-cooled inflation coextrusion film-forming machine to obtain a film F1 shown in FIG. 1 having a stable appearance with a thickness of 50 μm. The film could be formed, and the degree of biomass was about 88%. In addition, butene-1 (C4), which is a comonomer species contained in the straight-chain low-density polyethylene-based resin derived from sugar cane, is derived from petroleum, and the content thereof is 1 to 15 mol% (the same applies hereinafter).

  On the other hand, as Comparative Example 1 of the film F1, using a petrochemical-derived C4LL linear low-density polyethylene-based resin, in the same manner as in Example 1, the extrusion temperature was 200° C., the rotation speed was 60 rpm, and the thickness was 50 μm. It was 0% when it was formed into a film and the degree of biomass was measured.

上記結果から、サトウキビ（植物）由来直鎖状低密度ポリエチレン系樹脂（実施例１）は、石化由来直鎖状低密度ポリエチレン系樹脂（比較例１）に比べて、引張破断強度や引裂強さが強く、腰やシール強度は同等の強度を有し、弾性率が低く柔軟であることが分かる。このように、植物由来直鎖状低密度ポリエチレン系樹脂は、石化由来直鎖状低密度ポリエチレン系樹脂と比較して同等以上の物性を有し、石化由来直鎖状低密度ポリエチレン系樹脂の製造加工適性と遜色ないことが実証された。 The following respective physical property evaluation tests were performed on the resin composition of Example 1, and the obtained results are described below.

From the above results, the linear low-density polyethylene-based resin derived from sugar cane (plant) (Example 1) has a tensile breaking strength and a tear strength higher than those of the linear low-density polyethylene-based resin derived from petrification (Comparative Example 1). It is clear that the strength is high, the waist and the seal strength are equivalent, and the elastic modulus is low and it is flexible. Thus, the plant-derived linear low-density polyethylene-based resin has physical properties equal to or higher than those of the petrochemical-derived linear low-density polyethylene-based resin, It was proved that it is comparable to the processability.

The tensile breaking strength (elongation) was measured at a test speed of 500 mm/min using a Tensilon universal testing machine with reference to JIS-Z1702. N=3 JIS-K7127 test piece type 5 (dumbbell piece: minimum parallel width 6 mm, distance between chucks 80 mm).
The elastic modulus (tensile) was measured at a test speed of 1 mm/min. using a Tensilon universal tester in accordance with JIS-K7176. The strength when stretched by 1.5 mm was measured, and N=3 JIS-K7127 test piece type 2 reference (strip: width 15 mm, chuck distance 150 mm) was used.
The waist was measured using a loop stiffener 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).
Sealing strength was measured by using a heat seal tester TP-701S, placing 1 kgf/cm ² ×1.0 s PET 12 μm on one side on an evaluation sample for sealing, and using a Tensilon universal testing machine at a test speed of 300 mm/min. Width 15 mm N=3 140° C.

  Using a screw diameter 30 mmφ extruder, 50% of Braschem C4LL-LL118 (d=0.916, MFR=1.0 g/10 min), which is a linear low-density polyethylene resin derived from sugar cane (resin composition 1), is used. Wt% and 50 wt% of Ube Maruzen polyethylene LDPE-F120N (d=0.920, MFR=1.2 g/10 min), which is a linear low-density polyethylene-based resin 2 derived from petroleum, are melt-kneaded at 200° C., A resin composition was obtained. Then, using a top-blown air-cooled inflation coextrusion film-forming machine, the resin composition was molded into a film F2 shown in FIG. It was 44%.

  As the resin composition for the first layer and the resin for the third layer, Mitsui Chemicals C6LL-Evolution SP2020 (d=0.916, MFR=2.3 g/10 min) was melted at 200° C. using a screw diameter 30 mmφ extruder. Kneading was performed to obtain a resin composition. Similarly, as a resin composition for the second layer, using a screw diameter of 30 mmφ extruder, C4LL-LL118 (d=0.916, MFR=1.0 g/1.0 g/m) which is a straight chain low density polyethylene resin derived from sugar cane. 10 minutes) was melt-kneaded at 200° C. to obtain a resin composition. The layer ratio of the first layer:second layer:third layer was 1:1:1. Then, the resin composition was molded into a film F3 shown in FIG. 4 having a thickness of 130 μm under the processing conditions of an extrusion temperature of 200° C. and a rotation speed of 60 rpm by a two-kind three-layer top-blowing air-cooled inflation coextrusion film forming machine, and the biomass degree thereof was measured. Was about 29%.

  As the resin composition for the first layer and the resin for the third layer, Mitsui Chemicals C6LL-Evolution SP2020 (d=0.916, MFR=2.3 g/10 minutes) was melted at 200° C. using a screw diameter 30 mmφ extruder. Kneading was performed to obtain a resin composition. Similarly, as a resin composition for the second layer, using a screw diameter of 30 mmφ extruder, C4LL-LL118 (d=0.916, MFR=1.0 g/1.0) which is a linear low-density polyethylene-based resin derived from sugar cane. 10 minutes) 50 parts by weight and Ube Maruzen polyethylene LDPE-F120N (d=0.920, MFR=1.2 g/10 minutes) 50 parts by weight were melt-kneaded at 200° C. to obtain a resin composition. The layer ratio of the first layer: the second layer: the third layer was 1:2:1. Next, the resin composition was molded into a film F4 having a thickness of 130 μm shown in FIG. 5 under the processing conditions of an extrusion temperature of 200° C. and a rotation speed of 60 rpm by a two-kind three-layer top-blowing air-cooled inflation coextrusion film forming machine, and the biomass degree Was about 22%.

A two-component curing type urethane-based adhesive is used by using a biaxially stretched nylon film (ONy, Toyobo Haden N-1102) as the substrate film 5 having a thickness of 25 μm for the outer layer and the film F4 of Example 4. , ONy surface is coated with the adhesive at about 4 g/m ² and the corona-treated surface of polyethylene is laminated by a dry lamination method to obtain a laminated film 3 shown in FIG. 6 having a two-layer structure. Was about 18%.

  Then, using this laminated film 3, a refillable standing pouch with a spout part (packing bag 6) provided with a laser cutting line is prepared, and the contents are put into the refillable standing pouch to open the mouth. Regarding the sealed one, the contents were leaked, fallen, buckled, and the body was broken, but none were observed. Further, a drop test was conducted 5 times from a height of 1 m, but no bag breakage or leakage was observed.

An outer layer having a thickness of 25 μm, a biaxially stretched nylon film (ONy, Toyobo Haden N-1102) as the substrate film 5, and an intermediate layer having a thickness of 12 μm VMPET (metal evaporated film, which is vapor-deposited on one side with aluminum, A polyethylene terephthalate film having aluminum vapor-deposited thereon) is laminated on the aluminum vapor-deposited surface, and further, a two-component curing type urethane adhesive is applied to the polyethylene terephthalate surface of VMPET at about 4 g/m ² to form a film F4 of Example 4. The laminated film 3 having a three-layer structure was obtained by laminating the corona-treated surface of No. 1 with the dry lamination method. Then, using this laminated film 3, a refilling standing pouch (packing bag 6) with a spout for opening was provided by a laser, and the biomass degree was measured to be about 17%.

  Leakage, falling, buckling, and bending of the body were observed in the prepared refill standing pouch with the contents sealed and the mouth sealed, but none were observed. Further, a drop test was conducted 5 times from a height of 1 m, but no bag breakage, leakage, etc. were observed.

  Only the bottom material in the refillable standing pouch with the spout of Example 6 was used as a refillable standing pouch made using a petroleum-derived film made of stretched polyamide (ONY)/LLDPE (linear low-density polyethylene). Leakage, tipping, buckling, and bending of the body of the product with the mouth sealed was observed, but none were observed. Further, a drop test was conducted 5 times from a height of 1 m, but no bag breakage, leakage, etc. were observed. Therefore, for the bottom material of the standing pouch of the present invention, either the laminated film 3 containing the same plant-derived material as the body portion or the petroleum-derived film may be used.

  As in Example 1, using a screw diameter 30 mmφ extruder, C4LL-LL318 (d=0.918, MFR=2.7 g), which is a sugarcane-derived linear low-density polyethylene resin (resin composition 1), manufactured by Braschem Co., Ltd. /10 minutes) was melt-kneaded at 200° C. to obtain a resin composition. Then, the resin composition is molded by a T-die cast film forming machine under the processing conditions of an extrusion temperature of 220° C. and a rotation speed of 45 rpm to form a film having a thickness of 120 μm (3 layers of 1 type) and a stable appearance. And the degree of biomass was measured and was about 88%.

  In the same manner as in Example 1, using a screw diameter 30 mmφ extruder, C4LL-LL318 (d=0.918, MFR=2.7 g) which is a straight-chain low-density polyethylene-based resin (resin composition 1) derived from sugar cane. /10 min) and Mitsui Chemicals C6LL-Evolew SP2020 (d=0.918, MFR=3.8 g/10 min) at 7:3 at 200° C. and melted, and extruded by a T-die cast film forming machine. By molding the resin composition under the processing conditions of a temperature of 220° C. and a rotation speed of 45 rpm, a film having a thickness of 120 μm (1 layer, 3 layers) and a stable appearance can be formed. , About 59%.

  As described above in detail, the films F1 to F4 made of the polyethylene resin of this example are made of the resin composition 1 containing the linear low-density plant-derived polyethylene resin obtained by the gas phase polymerization method. Is. Further, these films F1 to F4 are used as sealant films to form the laminated film 3 laminated with the base film 5, and the packaging bag 6 is formed of the laminated film 3.

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

DESCRIPTION OF SYMBOLS 1 Resin composition 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-F4 film

Claims (5)

A packaging bag using a heat-sealable film made of polyethylene resin,
The heat-sealable film contains a plant-derived linear low-density polyethylene resin in an amount of 5 to 90% by weight, wherein plant-derived ethylene and petroleum-derived α-olefin are copolymerized by a gas phase polymerization method in the presence of a metallocene catalyst. And a film of a single-layer structure made of a resin obtained by mixing 10 to 95% by weight of a petroleum-derived polyethylene resin,
Linear low density polyethylene resin from the plant is characterized in that the biomass degree calculating from measurements of radiocarbon dating 14C is an ethylene -α- olefin copolymer of less than 80% to 100% packaging bag. A heat-sealable film made of polyethylene resin,
The heat-sealable film contains 5 to 90% by weight of a plant-derived linear low-density polyethylene-based resin in which plant-derived ethylene and petroleum-derived α-olefin are copolymerized by a gas phase polymerization method, and a petroleum-derived polyethylene. Consisting of a multi-layered film containing at least one layer of a resin in which 10 to 95% by weight of a resin is mixed,
The plant-derived linear low-density polyethylene-based resin is an ethylene-α-olefin copolymer having a biomass degree of 80 to less than 100% calculated from the measured value of radiocarbon dating 14C. Sealant film for lumber. The α-olefin is butene-1 or hexene-1 or a mixture thereof, and the plant-derived linear low-density polyethylene-based resin has a density of 0.910 to 0.925 g/cm 3, and a melt flow rate. Has a physical property of 0.5 to 4.0 g/10 minutes, The sealant film for a packaging material according to claim 2 , wherein. A laminated film for packaging material, comprising the sealant film for packaging material according to claim 2 or 3 laminated with a base film. A packaging bag comprising the sealant film for packaging material according to claim 2 or 3 .

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