JP7035420B2 - Sealant film for packaging liquid contents, packaging materials for liquid contents, packaging for liquid contents - Google Patents

Description

In the present invention, the elution organic substance originally contained in the packaging material and the odorous component generated from the packaging material during the sterilization / sterilization process are transferred to the liquid content in the packaging and transformed into the content. A sealant film for packaging liquid contents, which has excellent odor resistance and taste changeability, and a packaging material for liquid contents and a liquid content, which are produced by using the sealant film. Regarding the packaging.

As a packaging material, a packaging material containing an odor adsorbent that adsorbs an odor has been proposed (Patent Document 1). In such a packaging material, an odor adsorbent such as synthetic zeolite or activated carbon is kneaded into the resin material.

However, such a packaging material has a problem that it adsorbs not only odor but also moisture in the atmosphere and desorbs the odor once adsorbed, so that a sufficient odor adsorption effect can be obtained. Not.

A packaging material containing an odor adsorbent obtained by supporting a chemical adsorbent on an inorganic porous body is also known (Patent Document 2), but the main adsorbed object adsorbs an odor component having a specific functional group. However, in the situation where the resin material is not selected, the amount of organic substances having no functional group cannot be suppressed, and the odorous component cannot be sufficiently adsorbed.

Japanese Patent No. 2538487 Japanese Unexamined Patent Publication No. 2014-233408

The present invention solves the above-mentioned problems, is excellent in manufacturing suitability, and reduces elution organic substances originally contained in the packaging material, thereby causing UV irradiation, hot pack, boil, γ-ray irradiation, EB irradiation, etc. A sealant film for packaging liquid contents that has excellent odor resistance to liquid contents by reducing odorous substances generated by decomposition of the resin that constitutes the package during sterilization and sterilization. It is an object of the present invention to provide a packaging material for liquid contents and a packaging body for liquid contents produced by using the sealant film.

As a result of various studies, the present inventors have found a sealant film for packaging liquid contents and a sealant film having a low-eluting polyethylene-containing layer formed from a resin composition containing at least a specific low-eluting polyethylene. It has been found that the packaging material for liquid contents produced by using the above method, and further, the packaging material for liquid contents produced by using the packaging material for liquid contents achieves the above-mentioned object.

The present invention is characterized by the following points.
1. 1. A sealant film for packaging liquid contents, which has at least a low-eluting polyethylene-containing layer.
The low-eluting polyethylene-containing layer is formed from a resin composition containing low-eluting polyethylene.
The concentration of the elution TOC contained in the film made of the low-eluting polyethylene is 1.5 ppm or more and 250 ppm or less.
Sealant film for packaging liquid contents.
2. 2. The sealant film for packaging liquid contents according to 1 above, wherein the density of the low-eluting polyethylene is 0.90 g / cm ³ or more and 0.94 g / cm ³ or less.
3. 3. The sealant film for packaging liquid contents according to 1 or 2 above, wherein the low-eluting polyethylene is LLDPE.
4. The sealant for packaging liquid contents according to any one of 1 to 3 above, wherein the low-eluting polyethylene is one or more selected from the group of C4-LLDPE, C6-LLDPE, and C8-LLDPE. the film.
5. The number of pinholes generated after 5000 times of gelboflex at 23 ° C. in a 50 μm thick film made of the low-elution polyethylene simple substance is 0, or 1 or more, and 160 or less. The sealant film for packaging liquid contents described in any of the above. 6. A packaging material for liquid contents, which is produced by using the sealant film for packaging liquid contents according to any one of 1 to 5 above.
7. A package for liquid contents formed from the packaging material for liquid contents according to 6 above.

Since the sealant film for packaging the liquid contents of the present invention has a low-eluting polyethylene-containing layer formed from a resin composition containing a specific low-eluting polyethylene, the packaging material is originally contained in the sealant film. Eliminating organic substances and odors are reduced, and odors generated by decomposition of the resin constituting the laminate during sterilization and sterilization of UV irradiation, γ-ray irradiation, EB irradiation, hot packs, boil, etc. are also reduced. Will be done.
When a package for liquid contents is produced using the packaging material for liquid contents of the present invention, the amount of organic substances eluted in the filled liquid contents can be reduced and the change in odor can be suppressed. ..
Therefore, the packaging material for liquid contents of the present invention is suitable as a packaging material for liquid foods, pharmaceuticals, and medical products to be sterilized and sterilized.

It is the schematic sectional drawing which shows an example about the layer structure of the sealant film for packaging a liquid content of this invention. It is the schematic sectional drawing which shows an example about the layer structure of the sealant film for packaging a liquid content of this invention. It is the schematic sectional drawing which shows an example about the layer structure of the sealant film for packaging a liquid content of this invention.

The sealant film for packaging the liquid contents of the present invention and the package for the liquid contents produced by using the sealant film will be described in more detail below. The present invention will be described with reference to specific examples, but the present invention is not limited thereto.
<Layer structure of sealant film for packaging liquid contents of the present invention>
The sealant film for packaging liquid contents of the present invention is at least a sealant film for packaging liquid contents having a low-eluting polyethylene-containing layer formed from a resin composition containing low-eluting polyethylene, and is a sealant. It may be a layer consisting only of a layer having a low elution polyethylene-containing layer 3, or may include a base material layer or an adhesive layer.

Further, the sealant film 1 may have a multilayer structure of a low-eluting polyethylene-containing layer 3 and a non-low-eluting polyethylene-containing layer 2 not containing low-eluting polyethylene, as shown in FIGS. 1 and 2.
Further, as shown in FIG. 3, the low-eluting polyethylene-containing layer 3 may have a multilayer structure such as 3a and 3b having the same or different types and contents of the main low-eluting polyethylene.
When a package for liquid contents is produced by a packaging material using the sealant film for packaging liquid contents of the present invention, the innermost layer in contact with the liquid contents of the package is a low-elution polyethylene-containing layer 3. Alternatively, it may be the non-low elution polyethylene-containing layer 2.
Further, although not shown, the low-eluting polyethylene-containing layer 3 may consist of three or more layers having the same or different types and contents of the main low-eluting polyethylene.

<Low elution polyethylene>
The sealant film of the present invention has a low-eluting polyethylene-containing layer formed from a resin composition containing low-eluting polyethylene, which has heat-sealing properties and a small amount of organic substances eluted.
By reducing the amount of organic matter eluted, it is possible to reduce the concentration of organic matter eluted in the liquid content packed in the package for liquid content using the sealant film of the present invention and suppress the change in odor. can.

Here, the concentration of the organic substance in the liquid content is indicated by the concentration of total organic carbon (TOC) in the present invention.
TOC indicates the concentration of the total amount of organic substances (organic carbon bodies) that can be oxidized in water by the concentration of carbon content, and is used as one of the typical water quality indicators. It is standardized by organic carbon (TOC) automatic measuring instrument) and the like.
The concentration of the elution TOC contained in the film made of the low-elution polyethylene is 1.5 ppm or more and 250 ppm or less.

Here, the reason why the concentration of the elution TOC related to the low-eluting polyethylene as a single raw material is measured not in the state of the raw material pellets or the like but in the filmed state is that the low-eluting polyethylene is used for forming a sealant layer or the like. This is because when the film is formed, various thermal histories and the like may be given to increase the elution amount of TOC.
After filling 1 kg of distilled water as filling water in a pouch packaging bag having a thickness of 15 cm × 44 cm × 50 μm made of low-elution polyethylene in the present invention and eluting, the increased concentration of TOC in the filled water is 0. It is preferably 0.01 ppm or more and 1.5 ppm or less, more preferably 0.02 ppm or more and 1.45 ppm or less, and further preferably 0.025 ppm or more and 1.4 ppm or less.
When the increased concentration of TOC in the filling water is larger than 1.5 ppm, it is difficult to suppress the change in the odor of the filled water, and the cost is high to obtain the one smaller than 0.01 ppm. The effect is limited. From the viewpoint of achieving both cost and performance, the above range is preferable.

Here, the increased concentration of TOC in the filling water when the entire amount of the elution component contained in the pouch bag is eluted in 1000 g of the filling water is calculated as follows.
Pouch bag specific density: S [g / cm ³ ]
Pouch bag size: 15 cm x 44 cm x 50 μm thickness Pouch bag weight: W = 15 x 44 x 50 x 10 ^-4 x 2 x S = 6.6 x S [g]
Concentration of elution TOC contained in pouch bag: C [ppm]
Then
Total weight of elution TOC contained in the pouch bag = C × W [g]
Since this elutes in 1000 g of water,
Increased concentration of TOC in filled water = C × W / 1000 = C × 6.6 × S × 10 ^-3 [ppm]
]
For example, when the specific gravity of the low-eluting polyethylene film constituting the pouch bag is 0.92 and the concentration of the eluted TOC contained is 1.7 ppm,
Increased concentration of TOC in filled water = 1.7 x 6.6 x 0.92 x 10 ^-3 = 0.01 [ppm]
It is calculated as.

As a specific method for determining the increased concentration of TOC, for example, 1000 g of distilled water at 40 ° C to 80 ° C is filled in the above pouch packaging bag, and the temperature is 25 ° C to 50 ° C for several days to 4 weeks. The TOC concentration of the filled water after storage can be measured with a total organic carbon meter or HS-GC, and the TOC concentration of the distilled water can be subtracted as a blank.

In the present invention, a pouch bag (15 cm × 44 cm) package is prepared using a sealant film, and 1000 g of water (distilled water for high performance liquid chromatography, genuine chemicals) at 65 ° C. is filled and the package is liquid-filled. After preparing the product and storing it at 35 ° C. for 2 weeks, the increased concentration of TOC is determined by measuring the TOC concentration of the filled water with a TOC-L total organic carbon meter manufactured by Shimadzu Corporation as a standard method.
Then, the elution TOC concentration contained in the sealant film is calculated from the obtained TOC increase concentration of the filled water and the mass part of the filled water and the mass part of the sealant film.

Specific examples of the low-eluting polyethylene include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear (linear) low-density polyethylene (LLDPE), and ethylene-vinyl acetate. Low elution of polymers, ethylene-ethyl acrylate copolymers, ethylene-acrylic acid copolymers, ethylene-methacrylic acid copolymers, ethylene-methylmethacrylic acid copolymers, ethylene-propylene copolymers, etc. Things and mixtures of their resins include, but are not limited to these resins.

In order to reduce the amount of organic matter eluted from the low-eluting polyethylene film, the following methods can be mentioned, but the method is not limited thereto.

When producing polyethylene, it is effective to reduce the residual amount of unreacted raw materials, the amount of low molecular weight products and by-products, and to remove the polymerization catalyst. Specifically, it improves the purity of raw materials, precisely controls conditions such as reaction temperature and pressure, and removes unreacted raw materials, low molecular weight products, by-products, and polymerization catalysts by distillation and washing. Examples thereof include a method of preventing oxidation due to contact with oxygen in the air at a high temperature.

When pelletizing the produced polyethylene, there is a method of limiting the use of lubricants, antioxidants, and other additives that are likely to increase the elution amount of organic substances.
When forming polyethylene into a film, there is a method of limiting the use of lubricants, antioxidants, solvents, and other additives that are likely to increase the amount of organic matter elution to prevent oxidation due to high temperatures. Can be mentioned.
Since the sealant film of the present invention has heat-sealing properties and contains low-eluting polyethylene, the packaging material containing the sealant film has excellent heat-sealing properties, the amount of organic matter eluted is small, and packaging. It is possible to reduce the increase in the concentration of TOC in the liquid contents in the body.

Further, polyethylene is suitable in that it is resistant to sterilization and sterilization treatments such as UV and has a property of being hard to be decomposed.
Among these low-eluting polyethylenes, LLDPE is preferable as the type, and further, LLDPE having side chains of C4, C6, and C8 tends to reduce the elution amount of organic substances, and therefore C4-LLDPE. , C6-LLDPE, C8-LLDPE and the like are more preferable.
Here, C4, C6, and C8 are partially copolymerized with LLDPE, indicating that the monomer having the number of carbon atoms described is present in the side chain. For example, C4 represents butene-1, C6 represents hexene-1, or 4-methylpentene-1, and C8 represents the side chain of the structure of octene-1.

Alternatively, low-eluting polyethylene having a density of 0.90 g / cm ³ or more and 0.94 g / cm ³ or less is preferable, and low-eluting polyethylene having a density of 0.905 g / cm ³ or more and 0.933 g / cm ³ or less is preferable. More preferred. Low-eluting polyethylene with a density in this range tends to reduce the amount of organic matter eluted.

Further, the low-eluting polyethylene can also contain a small amount of additives such as an antioxidant and an anti-blocking agent.
Furthermore, it is preferable that the low-eluting polyethylene in the present invention is excellent in pinhole resistance due to bending when it is formed into a film by itself.
Fatigue fracture may progress and pinholes may occur in the packaging due to local repeated bending due to vibration during the packaging process or transportation. Therefore, packaging materials for foods and medical supplies are particularly resistant to pinholes. is important.

The pinhole resistance of the low-eluting polyethylene in the present invention is, for example, that the number of pinholes generated in a 50 μm-thick film made of a low-eluting polyethylene alone after 5000 gelboflexes at 23 ° C. is 0. Alternatively, the number is preferably 1 or more and 160 or less.

When the number of pinholes generated in the sealant film is within the above range, it is possible to produce a packaging material that can withstand practical use in applications that require pinhole resistance.
<Low elution polyethylene-containing layer>
The low-eluting polyethylene-containing layer in the present invention is formed from the resin composition containing the above-mentioned low-eluting polyethylene.
Further, it contains highly elution polyethylene, polypropylene, methylpentene polymer, acid-modified polyolefin resin, and a mixture of these thermoplastic resins within a range that does not impair the low elution property and heat sealability of the sealant film. It is possible, but not limited to these resins.

<Non-low elution polyethylene-containing layer>
The non-low-eluting polyethylene-containing layer in the present invention is a layer that does not contain low-eluting polyethylene and has, if necessary.
It is possible to include general-purpose polyethylene, polypropylene, methylpentene polymer, acid-modified polyolefin-based resin, and a mixture of these thermoplastic resins within a range that does not impair the low elution property and heat-sealing property of the sealant film. However, it is not limited to these resins.

<Formation of low-eluting polyethylene-containing layer and non-low-eluting polyethylene-containing layer>
(Film formation / lamination method)
In the present invention, the film forming and laminating method of each layer of the sealant film is not particularly limited, and known or conventional film forming methods and laminating methods can be applied.
A low-eluting polyethylene-containing layer or a non-low-eluting polyethylene-containing layer may be laminated by an extrusion coating on another layer, optionally via an adhesive layer, or, for example, a plurality of low-eluting polyethylene-containing layers may be contained. The layer and the non-low elution polyethylene-containing layer can also be formed by coextrusion by an inflation method or a casting method.

When laminating by extrusion coating, first, the resin composition forming the low-eluting polyethylene-containing layer and the resin composition forming the non-low-eluting polyethylene-containing layer are heated and melted, and are required with a T-die. The molten resin is expanded and stretched in a wide width direction and extruded into a curtain shape, and the molten resin is allowed to flow down onto the surface to be laminated and sandwiched between a rubber roll and a cooled metal roll to form a low-eluting polyethylene-containing layer or non-low-eluting. The polyethylene-containing layer is formed, adhered to the surface to be laminated, and laminated at the same time.

The melt flow rate (MFR) of the low-eluting polyethylene contained in the low-eluting polyethylene-containing layer and the thermoplastic resin contained in the non-low-eluting polyethylene-containing layer when laminated by the extrusion coating is 0.2 to 50 g. It is preferably / 10 minutes, more preferably 0.5 to 30 g / 10 minutes. In this specification, MFR is a value measured by a method based on JIS K7210.
If the MFR is less than 0.2 g / min or 50 g / min or more, it is difficult to be effective in terms of processing suitability.
When the inflation method is used, the melt flow rate (MFR) of the low-eluting polyethylene contained in the low-eluting polyethylene-containing layer and the thermoplastic resin contained in the non-low-eluting polyethylene-containing layer is 0.2 to 10. It is preferably 0 g / 10 minutes, more preferably 0.2 to 9.5 g / 10 minutes.
If the MFR is less than 0.2 g / 10 min or 10.0 g / 10 minutes or more, it tends to be inferior in terms of processing suitability.

Alternatively, the pre-formed low-eluting polyethylene-containing layer and the non-low-eluting polyethylene-containing layer may be laminated via an adhesive layer by dry lamination, non-solvent lamination, sand lamination or the like.

<Adhesive layer>
In the present invention, it is also possible to provide an adhesive layer between the sealant film and the base film and between the layers of the sealant film for laminating.
The adhesive layer may consist of an adhesive or any anchor coating agent.
The adhesive may be a thermosetting type, an ultraviolet curing type, an electron beam curing type, or the like, and may be in any form such as an aqueous type, a solution type, an emulsion type, a dispersed type, and the properties thereof are film / sheet. It may be in any form such as a form, a powder form, a solid form, and the like, and the bonding mechanism may be any form such as a chemical reaction type, a solvent volatilization type, a thermosetting type, and a thermosetting type.
The adhesive layer may be an EC (extrusion coat) layer, a dry laminating adhesive, a non-solvent laminating adhesive, or the like.

The components forming such an adhesive layer include polyvinyl acetate adhesives such as polyvinyl acetate and vinyl acetate-ethylene copolymers, and copolymers of polyacrylic acid with polystyrene, polyester, polyvinyl acetate and the like. Polyacrylic acid adhesive, cyanoacrylate adhesive, ethylene copolymer adhesive consisting of a copolymer of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid, cellulose adhesive, Polyurethane adhesive, polyester adhesive, polyamide adhesive, polyimide adhesive, polyolefin adhesive such as LDPE, amino resin adhesive composed of urea resin or melamine resin, phenol resin adhesive, epoxy adhesive Adhesives, reactive (meth) acrylic adhesives, chloroprene rubbers, nitrile rubbers, elastomeric adhesives made of styrene-butadiene rubbers, silicone adhesives, alkali metal silicates, inorganic adhesives made of low melting point glass, etc. And so on.

As the anchor coating agent, for example, an organic titanium-based, isocyanate-based, polyethyleneimine-based, acid-modified polyethylene-based, polybutadiene-based anchor coating agent can be used.

When the adhesive layer is laminated with an extrusion coating, the adhesive can be formed by an extrusion coating on the layer to be adhered, without particular limitation.
In the extrusion coating, first, the adhesive is heated and melted, expanded and stretched in the required width direction with a T-die, extruded into a curtain shape, and the melt is allowed to flow down onto the layer to be bonded to be cooled with a rubber roll. By sandwiching it with the metal roll, the adhesive layer is formed, and the adhesive layer is adhered to and laminated at the same time.

When an adhesive for dry laminating is used as the adhesive layer, an adhesive dispersed or dissolved in a solvent is applied onto one layer, dried, and the other layer to be adhered is laminated and then laminated at 30 to 120 ° C. By aging for several hours to several days, the adhesive is cured and laminated.
When using a non-solvent laminating adhesive, the adhesive itself is applied onto the layer without being dispersed or dissolved in a solvent, dried, and the other layer to be bonded is laminated and then laminated at 30 to 120 ° C. By aging for several hours to several days, the adhesive is cured and laminated.

The adhesive layer is formed by applying the above adhesive with, for example, a roll coat, a gravure roll coat, a kiss coat, or the like, and the coating amount thereof is preferably about 0.1 to 10 g / m ² (dry state). Good adhesiveness can be obtained by setting the coating amount of the adhesive within the above range.
When laminating each layer of the sealant film by sand lamination, any resin that can be heated and melted and applied by an extruder can be used as the adhesive layer. Specifically, the thermoplastic resin used for the above-mentioned non-odor adsorbing layer can be preferably used.

<Packaging material>
The packaging material for packaging the liquid contents of the present invention contains a layer composed of a sealant film for packaging the liquid contents of the present invention, and may be composed only of the sealant film, and may be based on the present invention, if necessary. It may also have a material layer, a functional material layer, an adhesive layer and the like. As the base material layer, the functional layer, and the adhesive layer, known ones can be laminated and used by a known method.

<Packaging>
The liquid content packaging of the present invention is, for example, a bag made of the packaging material for packaging the liquid content of the present invention, and the packaging material is bent so that the surfaces having good heat sealability face each other. Alternatively, two sheets are overlapped, and the peripheral ends thereof are, for example, a side seal type, a two-way seal type, a three-way seal type, a four-way seal type, an envelope sticker seal type, a gassho sticker sticker type (pillow seal type), and a fold seal type. , Flat-bottomed seal type, square-bottomed seal type, gusset type, etc. can be manufactured by heat-sealing.
As a 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, or an ultrasonic seal can be applied.

<Liquid contents>
In the present invention, the liquid content refers to all seasoning liquids such as drinking water, juices, infusions for drip, soy sauce, sauces, and liquids such as soups, honeys, sauces, and dressings.

The details of the raw materials used in the examples are as follows.
[Low-eluting polyethylene and high-eluting polyethylene]

<Example 1>
Using the Ultozex 1520L shown in Table 1, a single-layer sealant film having a film thickness of 50 μm was obtained by inflation film formation at a film formation temperature of 160 ° C.
Next, the pinhole resistance, TOC increase concentration, and odor change due to this sealant film were evaluated. The evaluation results are shown in Table 2.

<Examples 2 to 8, Comparative Example 1>
Polyethylene was selected and used according to the description in Table 1, and a film was formed in the same manner as in Example 1 to obtain a single-layer sealant film having a film thickness of 50 μm, which was evaluated in the same manner.

<Example 9>
Using Evolu SP2020 and Ultozex 3500ZA shown in Table 1, they are laminated by inflation film formation at a film formation temperature of 160 ° C., and have a three-layer structure consisting of a non-odor adsorption layer 3 μm / odor adsorption layer 44 μm / non-odor adsorption layer 3 μm. Obtained a sealant film.
Then, it was evaluated in the same manner as in Example 1. Table 2 shows the structure of the laminated body and the evaluation results.

<Evaluation>
[Film formation]
The appearance of the sealant film was observed and sensually evaluated. The evaluation criteria are as follows.
◯: Film formation is possible without wrinkles or bumps on the film.
X: Many wrinkles and bumps occur on the film, making it difficult to form a film.

[Heat sealability]
The sealant film produced in Examples and Comparative Examples and the PET film are laminated under the following conditions by EC (extraction coating) of the adhesive layer material to obtain a film-like laminate, and the film laminate is 10 cm. Cut into x10 cm, fold in half and stack, and heat-seal the 1 cm x 10 cm area using a heat-seal tester (Tester Sangyo Co., Ltd .: TP-701-A), without heat-sealing the edges. A sample was prepared in a state where it was not adhered and was divided into two parts.
This sample was cut into strips with a width of 15 mm, and each of the bifurcated ends was mounted on a tensile tester to measure the tensile strength (N / 15 mm), and a pass / fail judgment was made.

(Approximate layer structure of the laminated body)
PET film (12 μm) / EC layer (15 μm) / Sealant layer (50 μm)
(Laminating condition)
Extrusion temperature: 330 ° C
Adhesive layer material: LDPE (Novatec LC520)
Adhesive layer thickness: 15 μm
(Heat seal condition)
Temperature: 160 ° C
Pressure: 1kgf / cm ²
Time: 1 second (tensile strength test conditions)
Test speed: 300 mm / min Load range: 50 N
(Pass / Fail Judgment Criteria)
◯: 30N / 15mm or more, passed.
×: Less than 30N / 15mm and failed.

[TOC increase concentration]
Using each of the sealant films obtained in Examples and Comparative Examples, a pouch bag (15 cm × 44 cm) was prepared, and the sealant film was subjected to UV irradiation sterilization treatment in advance.
Then, 1000 g of water at 65 ° C. (distilled water for high performance liquid chromatography, genuine chemistry) was hot-packed in each of the obtained packages to prepare a package liquid filler, and after storage at 35 ° C. for 2 weeks, The TOC concentration of the filled water was measured by a TOC-L total organic carbon meter manufactured by Shimadzu Corporation.

Next, the TOC concentration of the water before filling was measured in the same manner.
The TOC increase concentration in each package was calculated from the following formula.
TOC increase concentration = TOC concentration of filled water after storage-TOC concentration of water before filling TOC concentration of water before filling: 0.02 ppm
UV irradiation sterilization treatment conditions UV wavelength: 253.7 nm
Irradiation time: 10 seconds
Temperature: 25 ° C

[Pinhole resistance]
The sealant films produced in Examples and Comparative Examples were cut into A4 size (30 cm × 21 cm), bent with a gelboflex tester (BE-1005 manufactured by Tester Sangyo Co., Ltd.), and then each sample was 30 cm × 21 cm. The number of pinholes generated in the plane of was counted.
Temperature: 23 ° C
Gerbo bending frequency: 5000 times

[Taste change]
A pouch bag (13 cm × 17 cm) was prepared using each of the sealant films obtained in Examples and Comparative Examples. The sealant film was previously subjected to UV irradiation sterilization treatment. The UV irradiation sterilization treatment conditions are as follows.
UV irradiation sterilization treatment conditions UV wavelength: 253.7 nm
Irradiation time: 10 seconds
Temperature: 25 ° C
The pouch bag obtained here is filled with 100 g of water heated to 65 ° C (manufactured by Suntory Ltd., natural water in Japan) in a hot pack to prepare a package liquid filling, and then at 10 ° C, 1 A sensory evaluation was performed after weekly storage.

The evaluation indicators are as follows. There were 5 participants in the sensory evaluation experiment, and the average value was calculated and used as the evaluation result.
1: Strong odor 2: Slightly reduced odor 3: Significantly reduced odor 4: Equivalent to water before filling

<Summary of results>
The packages of all the examples using low-eluting polyethylene showed good film-forming property and sealing strength, the TOC increase concentration was small, and the odor change was good.
Furthermore, Examples 1 to 6 and 9 showed better pinhole resistance than Examples 7 and 8.
Comparative Example 1 containing no low-eluting polyethylene showed good film-forming property and seal strength, but showed a large increase in TOC concentration and a severe odor change.

1. 1. Sealant film 2. Non-low elution polyethylene-containing layer 3. Low-eluting polyethylene-containing layer 3a. Low-eluting polyethylene-containing layer (concentration a)
3b. Low-eluting polyethylene-containing layer (concentration b)

Claims (6)

A sealant film for packaging liquid contents, which has at least a low-eluting polyethylene-containing layer.
The low-eluting polyethylene-containing layer is a layer for reducing odorous substances generated from a resin constituting a packaging material during sterilization / sterilization treatment.
The low-eluting polyethylene-containing layer is formed from a resin composition containing low-eluting polyethylene.
The density of the low-eluting polyethylene is 0.90 g / cm ³ or more and 0.94 g / cm ³ or less.
The concentration of elution TOC contained in the film made of low-eluting polyethylene is 47.8 ppm or more and 119.4 ppm or less.
The sealant film includes one layer composed of only the low-eluting polyethylene-containing layer, two layers composed of the low-eluting polyethylene-containing layer and the non-low-eluting polyethylene-containing layer, or a non-low-eluting polyethylene-containing layer. It is one of three layers in which the low-eluting polyethylene-containing layer and the non-low-eluting polyethylene-containing layer are arranged in this order.
Sealant film for packaging liquid contents. The sealant film for packaging liquid contents according to claim 1 , wherein the low-eluting polyethylene is LLDPE. The sealant film for packaging liquid contents according to claim 1 or 2 , wherein the low-eluting polyethylene is one or more selected from the group of C4-LLDPE, C6-LLDPE, and C8-LLDPE. Claims 1 to 3 in which the number of pinholes generated after 5000 times of gelboflex at 23 ° C. in a 50 μm-thick film made of the low-eluting polyethylene alone is 0, or 1 or more and 160 or less. The sealant film for packaging liquid contents according to any one of the above items. A packaging material for liquid contents, which is produced by using the sealant film for packaging liquid contents according to any one of claims 1 to 4 . A package for liquid contents formed from the packaging material for liquid contents according to claim 5 .

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