JP2019064634A - SEALANT FILM FOR LIQUID CONTENT PACKAGE, AND PACKAGE MATERIAL FOR LIQUID CONTENT, PACKAGE FOR LIQUID CONTENT - Google Patents

Abstract

PROBLEM TO BE SOLVED: To exert a high adsorption effect on an odor generated by decomposition of an elution organic substance contained in a packaging material and a resin constituting a package during sterilization / sterilization treatment, and to resist odor to liquid contents. Provided are a sealant film for packaging liquid contents and a package for liquid contents using the sealant film, which has excellent taste changeability. A sealant film for packaging liquid contents having an odor adsorbing layer, which is formed of a resin composition containing a low-eluting polyethylene, and the odor adsorbing layer contains a low-eluting polyethylene and an odor adsorbent. The concentration of elution TOC contained in the film made of low-eluting polyethylene formed from the resin composition is 1.5 ppm or more and 250 ppm or less, and the odor adsorbent has a SiO2 / Al2O3 molar ratio of 30 /. A sealant film for packaging liquid contents, which comprises 1-10000/1 hydrophobic zeolite and whose odor adsorbent contains a chemical adsorbent-supported inorganic porous body. [Selection diagram] Fig. 1

Description

  In the present invention, the leachable organic substance originally contained in the packaging material and the odor component generated from the packaging material during sterilization / sterilization are transferred to the liquid contents in the package and changed into the contents. And a sealant film for liquid content packaging, which is excellent in odor and odor change resistance, and for packaging material for liquid contents and liquid content prepared using the sealant film It relates to a package.

In packaging materials, packaging materials containing an odor adsorbent that adsorbs odor have been proposed (Patent Document 1). In such packaging materials, odorous adsorbents such as synthetic zeolite and activated carbon are mixed into the resin material.
However, such a packaging material has a problem that it adsorbs not only the odor but also the moisture in the atmosphere and desorbs the odor once adsorbed, so a sufficient odor adsorbing effect can be obtained. Not.
There is also known a packaging material containing an odor adsorbent comprising a chemical adsorbent supported on an inorganic porous body (Patent Document 2), but the main adsorption target adsorbs an odor component having a specific functional group. Only in the situation where the resin material is not selected, the generation amount of the organic substance having no functional group can not be suppressed, and the odor component can not be sufficiently adsorbed.

Patent No. 2538487 JP, 2014-233408, A

The present invention solves the above-mentioned problems, and is superior in production suitability, and leachable organic substances originally contained in the packaging material, and sterilization / sterilization such as UV irradiation, hot pack, boiling, gamma irradiation, EB irradiation, etc. At the time of processing, it exerts a high adsorption effect on the odor generated due to the decomposition of the resin constituting the package, etc. to deodorize.
And, since it is possible to perform odor adsorption efficiently, since it is difficult to desorb odor once adsorbed, odor adsorption ability does not decrease, and a high adsorption effect is exhibited over a long period, and odor resistance to liquid contents It is an object of the present invention to provide a sealant film for packaging liquid contents excellent in variability, a packaging material for liquid contents produced using the sealant film, and a package for liquid contents.

  As a result of various studies, the present inventors have identified at least a sealant film for liquid content packaging having an odor absorbing layer, wherein the sealant film having the odor absorbing layer is a specific low elution polyethylene, And a sealant film for liquid content packaging containing a specific hydrophobic zeolite as an odor adsorbent, a sealant film for liquid content packaging, wherein the odor adsorbent further contains a specific chemical adsorbent-supporting inorganic porous material, It has been found that a packaging material for liquid contents prepared using a sealant film and a package for liquid contents prepared using the packaging material for liquid contents achieve the above object.

The present invention is characterized by the following points.
1. It is a sealant film for liquid content packaging which has an odor adsorption layer at least,
The sealant film is formed of a resin composition containing low elution polyethylene, and the odor absorbing layer is formed of a resin composition containing low elution polyethylene and an odor adsorbent.
The concentration of elution TOC contained in the film made of the low elution polyethylene is 1.5 ppm or more and 250 ppm or less,
The odor adsorber comprises hydrophobic zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 30/1 to 10000/1.
Sealant film for liquid content packaging.
2. The sealant film for liquid content packaging according to the above 1, wherein the odor adsorbent further comprises a chemical adsorbent-supporting inorganic porous material.
3. The sealant film for liquid content packaging according to the above 1 or 2, wherein the density of the low elution polyethylene is 0.90 g / cm ³ or more and 0.94 g / cm ³ or less.
4. The sealant film for liquid content packaging in any one of said 1-3 whose said low elution polyethylene is LLDPE.
5. The sealant for liquid content packaging according to any one of the above 1 to 4, wherein the low elution polyethylene is one or two or more selected from the group consisting of C4-LLDPE, C6-LLDPE, and C8-LLDPE. the film.
6. The number of pinholes generated after 5000 times of gelvoflex at 23 ° C. of the 50 μm-thick film consisting of the low elution polyethylene alone is 0, or 1 or more and 160 or less according to the above 1 to 5 The sealant film for liquid content packaging according to any of the above. 7. The said odor adsorber is melt-kneaded in a mass ratio of the odor adsorber / thermoplastic resin in the ratio of 0.5 / 99.5-40 / 60 beforehand with the thermoplastic resin The sealant film for liquid content packaging according to any of the above.
8. The sealant film for liquid content packaging according to 7 above, wherein the melt flow rate of the thermoplastic resin is 0.2 to 10.0 g / 10 min.
9. The sealant film for liquid content packaging according to any one of the above 1 to 8, wherein the content of the odor adsorbing body is 0.3% by mass or more and 15% by mass or less in the entire sealant film. 10. The sealant film for liquid content packaging according to any one of 1 to 9, wherein the sealant film has a non-odor absorbing layer on the surface and / or the back of the odor absorbing layer.
11. 11. The chemical adsorbent according to any one of the above 1 to 10, which has a functional group having reactivity with one or more selected from the group consisting of aldehydes, ketones, and carboxylic acids. Sealant film for packaging liquid contents.
12. The sealant film for liquid content packaging according to any one of the above 1 to 11, wherein the chemical adsorbent has an amino group.
13. The sealant film for liquid content packaging in any one of said 1-12 whose content of the said hydrophobic zeolite is 0.3 mass% or more and 15 mass% or less in all the said odor adsorption layers.
14. The packaging material for liquid contents produced using the sealant film for liquid contents packaging in any one of said 1-13.
15. The package for liquid contents formed from the packaging material for liquid contents as described in 14 above.

The sealant film for liquid content packaging of the present invention has an odor-adsorbing layer of a specific constitution and contains a specific low-eluting polyethylene, so that the elutable material originally contained in the packaging material is Organic substances and odor are reduced, and the odor generated by decomposition of the resin that constitutes the laminate during sterilization / sterilization treatment such as UV irradiation, γ irradiation, EB irradiation, hot pack, boiling, etc. is efficiently performed over a long period of time It has the effect of adsorbing.
Due to these effects, when the liquid content packaging material of the present invention is used to produce a liquid content packaging, the amount of organic matter eluted in the filled liquid content is reduced, and the odor taste is changed. It can be suppressed.
Therefore, the packaging material for liquid contents of the present invention is suitable as a packaging material for liquid food, medicine and medical products to be subjected to sterilization and sterilization treatment.

It is a schematic sectional drawing which shows the example about the laminated constitution of the sealant film for liquid content packaging of this invention. It is a schematic sectional drawing which shows the example about the laminated constitution of the sealant film for liquid content packaging of this invention. It is a schematic sectional drawing which shows the example about the laminated constitution of the sealant film for liquid content packaging of this invention. It is a figure which shows the adsorption | suction mechanism with respect to the odor substance of a chemical adsorbent carrying inorganic porous body.

  The sealant film for liquid content packaging of the present invention and the package for liquid content produced using the sealant film will be described in more detail below. Although a specific example is shown and demonstrated, this invention is not limited to this.

<Layer Configuration of Sealant Film for Liquid Content Packaging of the Present Invention>
The sealant film for liquid content packaging of the present invention is at least a sealant film for liquid content packaging having an odor absorbing layer, and may be only a layer functioning as a sealant, and from the odor absorbing layer 3 only Or a base layer or an adhesive layer.
Furthermore, as shown in FIGS. 1 and 2, the sealant film 1 may have a multilayer structure of the odor adsorbing layer 3 and the non-odor adsorbing layer 2 not containing an odor adsorbing material, and in the case of FIG. Sealing strength and interlayer adhesion strength can be improved.
Further, as shown in FIG. 3, the odor adsorbing layer 3 has a multilayer structure such as 3a, 3b, etc., in which the type of low elution polyethylene as the main component and the type and content of the odor adsorber are the same or different. Good.

  When a package for liquid contents is produced by the packaging material using the sealant film for liquid contents packaging of the present invention, even the odor absorbing layer 3 is the innermost layer in contact with the liquid contents of the package. And the non-odor adsorption layer 2 may be used. When the non-odor adsorption layer 2 is the innermost layer, the seal strength of the package can be improved, and when the odor adsorption layer 3 is the innermost layer, the interlayer adhesion strength in the package can be improved.

  Furthermore, although not shown in the drawings, the odor adsorbing layer 3 may be composed of three or more layers having the same type or different contents of the type of low elution polyethylene as the main component, and the type and content of the odor adsorbent.

<Low elution polyethylene>
The sealant film of the present invention contains a low elution polyethylene which has heat sealability and a small amount of elution of organic matter.
It is possible to suppress the change in odor taste by reducing the concentration of the organic matter eluted in the liquid content filled in the liquid content package using the sealant film of the present invention by the small amount of the eluted organic matter. it can.

Here, in the present invention, the concentration of the organic substance in the liquid content is the total organic carbon (TOC =
Indicated by the concentration of Total Organic Carbon).
TOC is the concentration of the total amount of organic substances (organic carbons) that can be oxidized in water expressed as the concentration of carbon content, and is used as one of the representative water quality indicators, and is specified in JIS K 0805 ( Standardized by organic carbon (TOC) automatic measuring instrument etc.
The concentration of the soluble 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 for measuring the concentration of leachable TOC with respect to the low-eluting polyethylene as a single raw material not in the state of raw material pellets etc. but in a filmed state is that low-eluting polyethylene is a sealant layer formation etc. This is because when being filmed, 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 and eluting it into a 15 cm × 44 cm × 50 μm thick pouch packaging bag of low elution polyethylene according to the present invention, the increasing concentration of TOC in the filling water is 0 It is preferable that the amount is 0.11 ppm or more and 1.5 ppm or less, more preferably 0.02 ppm or more and 1.45 ppm or less, and still more preferably 0.025 ppm or more and 1.4 ppm or less.
If the increase concentration of TOC in the filling water is greater than 1.5 ppm, it is difficult to suppress the change in the taste of the filling water, and while it is expensive to obtain 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 increase concentration of TOC in the filling water is calculated as follows when the total amount of the eluting component contained in the above pouch bag is eluted in 1000 g of the filling water.
Pouch bag specific gravity: 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 soluble TOC contained in pouch bag: C [ppm]
If you
Total weight of soluble TOC contained in the pouch bag = C × W [g]
As this dissolves in 1000 g of water,
Increase concentration of TOC in the filling water = C × W / 1000 = C × 6.6 × S × 10 ^-3 [ppm]
For example, when the specific gravity of the low elution polyethylene film constituting the pouch bag is 0.92, and the concentration of the elution TOC contained is 1.7 ppm,
Increasing concentration of TOC in the filling water = 1.7 × 6.6 × 0.92 × 10 ^-3 = 0.01 [ppm]
It is calculated as

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

In the present invention, a sealant film is used to make a package of pouch bag (15 cm × 44 cm) and filled with 1000 g of water at 65 ° C. (distilled water for high performance liquid chromatography, Junsei Chemical) to make the package liquid filled The product is prepared, and after storage at 35 ° C. for 2 weeks, the increase concentration of TOC is determined by using a TOC-L total organic carbon meter manufactured by Shimadzu Corporation as a standard method to measure the TOC concentration of filled water.
Then, the elution TOC concentration contained in the sealant film is calculated from the TOC increase concentration of the obtained filling water, and the filling water mass part and the sealant film mass part.

  Specific examples of low elution polyethylene include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), ethylene-vinyl acetate co-polymer Low elution of polymers, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl methacrylic acid copolymer, ethylene-propylene copolymer, etc. Include, but are not limited to, those and mixtures of those resins.

In order to lower the elution amount of the organic substance from the low elution polyethylene film, the following methods may be mentioned, but not limited thereto.
When producing polyethylene, it is effective to reduce the amount of unreacted raw material remaining, low molecular weight products and byproducts, and to remove the polymerization catalyst. Specifically, the purity of the raw material is improved, the conditions such as the reaction temperature and pressure are precisely controlled, and the unreacted raw material, low molecular weight products, byproducts and polymerization catalyst are removed by distillation or washing, There is a method of preventing oxidation by contact with oxygen in the air at high temperature.

In pelletizing the produced polyethylene, there may be mentioned a method of restricting the use of additives such as lubricants, antioxidants, and the like which would increase the elution amount of the organic matter.
When making polyethylene into a film, it is possible to limit the use of additives such as lubricants, antioxidants, solvents, and other additives that would increase the amount of elution of organic substances, and to prevent oxidation at high temperatures. It can be mentioned.

  The sealant film of the present invention has heat sealability and contains low elution polyethylene, whereby the packaging material containing the sealant film has excellent heat sealability, and the amount of elution of organic matter is small, and packaging It is possible to lower the concentration increase of TOC of the liquid contents in the body.

Also, polyethylene is preferable in that it has resistance to sterilization and sterilization such as UV and is difficult to be decomposed.
Among these low elution polyethylenes, LLDPE is preferable as the type, and furthermore, LLDPE having C4, C6, and C8 side chains tends to lower the elution amount of organic substances, and thus C4-LLDPE. , C6-LLDPE, C8-LLDPE and the like are more preferable.
Here, C4, C6, and C8 are partially copolymerized with LLDPE, and indicate that a monomer having the indicated numerical value of carbon number is present in the side chain. For example, C4 represents butene-1, C6 represents hexene-1, or 4 methylpentene-1, C8 represents the side chain of the structure of octene-1.

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

The low elution polyethylene can also contain small amounts of additives such as an antioxidant and an antiblock agent.
Furthermore, it is preferable that the low elution polyethylene in the present invention is excellent in pinhole resistance due to bending when it is formed into a film alone.

The package may suffer from fatigue failure due to local repeated bending due to vibration during the packaging process or during transportation, which may cause pinholes, so packaging materials especially for food and medical products have pinhole resistance. is important.
The pinhole resistance of the low elution polyethylene in the present invention is, for example, the number of pinholes generated after 5000 times of gelvoflex at 23 ° C. of a 50 μm thick film consisting of low elution polyethylene alone, Or it is preferable that it is one or more and 160 or less.
If the number of pinholes generated in the sealant film is in the above range, a packaging material that can withstand practical use can be produced for applications that require pinhole resistance.

<Odor adsorption layer>
The odor adsorbing layer in the present invention is formed of a resin composition containing the above-mentioned low elution polyethylene and a specific hydrophobic zeolite as an odor adsorber.
Furthermore, general-purpose polyethylene, polypropylene, methyl pentene polymer, acid-modified polyolefin resin, and a mixture of these thermoplastic resins, etc. may be contained within the range that does not inhibit the low elution property and heat sealability of the sealant film. Although possible, it is not limited to these resins.

[Odor adsorber]
In the present invention, the odor adsorber contains a specific hydrophobic zeolite. Furthermore, a chemical adsorbent carrying inorganic porous body can also be included.

(Hydrophobic zeolite)
<Hydrophobic Zeolite>
Generally, the higher the SiO ₂ / Al ₂ O ₃ molar ratio, the higher the hydrophobicity of the zeolite, and in the present invention, the hydrophobic zeolite contained in the odor adsorption layer has a SiO ₂ / Al ₂ O ₃ molar ratio And preferably 30 to 10,000.
The hydrophobic zeolite exerts an adsorbing effect of the odor component particularly when the sealant film or the packaging material using the sealant film is exposed to 230 ° C. or more.
The hydrophobic zeolite may have any external shape such as a sphere, a rod, or an ellipse, and may have any form such as powdery, lumpy, granular, etc. The powder form is preferable from the viewpoint of uniform dispersion and kneading characteristics.

  In the present invention, although the average particle diameter of the hydrophobic zeolite can be appropriately selected depending on the application, one having an average particle diameter of 0.01 μm to 10 μm is preferable. Here, the average particle size is a value measured by a dynamic light scattering method.

  When the average particle size is smaller than 0.01 μm, aggregation of the hydrophobic zeolite tends to occur, and the dispersibility in polyethylene tends to be reduced. In addition, when the average particle size is larger than 10 μm, the film forming property of the odor adsorption layer tends to be poor, so it is difficult to add a lot of hydrophobic zeolite, and the surface area is further reduced. There is a possibility that the odor effect can not be obtained.

The content of the hydrophobic zeolite is preferably 0.3% by mass or more and 15% by mass or less in all the odor adsorbing layers.
In the present invention, the addition amount of the hydrophobic zeolite can exhibit sufficient odor adsorptive effects if it is contained in the odor adsorptive layer by 0.1% by mass or more, but the odor is good as a package In order to obtain the adsorptive effect, the content is preferably 0.3% by mass or more, and more preferably 0.5% by mass or more. On the other hand, in order to obtain good film-forming property at the time of laminate production, in addition, in order to achieve good heat-sealability, the addition amount of hydrophobic zeolite is preferably 15% by mass or less, and 10% by mass It is more preferable that
Furthermore, in the hydrophobic zeolite in the present invention, by adjusting the SiO ₂ / Al ₂ O ₃ molar ratio to 30 to 10000, the adsorption of water can be suppressed, and a high odor adsorption ability can be expressed.

(Chemical adsorbent carrying inorganic porous material)
In the present invention, the chemical adsorbent-supporting inorganic porous material is one in which the inorganic porous material supports the chemical adsorbent, and it is possible to use a soluble organic substance, UV irradiation, γ-ray irradiation, EB irradiation, hot pack, boil, etc. Etc. It has a function of adsorbing odorous substances generated from the package at the time of sterilization / sterilization treatment.
As a loading method, a known or commonly used loading method can be applied. For example, a solution containing a chemical adsorbent as described below is impregnated into an inorganic porous material and supported by drying. it can.

In the present invention, the odor adsorbing layer containing the chemical adsorbent supported on the inorganic porous material is contained in the odor adsorbing layer, whereby the adsorption capacity per unit mass of the chemical adsorbent can be greatly enhanced, and The content of the chemical adsorbent and the odor adsorbent can be reduced. In addition, physical adsorption characteristics to the pores of the inorganic porous material can also be expected.
As a result, high seal strength can be obtained, and the excellent heat sealability and film formability required as a sealant film can be maintained.
If the content of the odor adsorber is 0.1% by mass or more in the entire sealant film, sufficient adsorption effect can be exhibited, but in order to obtain a good adsorption effect as a package, It is preferable that it is 0.3 mass% or more, and it is more preferable that it is 0.5 mass% or more.
On the other hand, in order to obtain good film forming property at the time of laminate production, additionally, in order to achieve good heat sealability, the content of the odor adsorbent is 15% by mass or less in the entire sealant film. Is preferable, and 10% by mass or less is more preferable.

  The odor adsorber may have any external shape such as a sphere, a rod, or an ellipse, and may have any form such as powder, lump, granules, etc. A powder form is preferable from the viewpoint of uniform dispersion in a thermoplastic resin, kneading characteristics, and the like.

Depending on the application, the odor adsorber can be selected appropriately from those having an average particle size, but in the present invention, those having an average particle size of 0.01 μm to 10 μm are particularly preferable, and 0.1 μm to 8 μm. Is more preferable, and 1 μm to 7 μm is more preferable. Here, the average particle size is a value measured by a dynamic light scattering method.
When the average particle size is smaller than 0.01 μm, aggregation of the odor adsorber tends to occur, and the dispersibility of the odor adsorber in the low elution polyethylene tends to decrease.
When the average particle size is larger than 10 μm, the film forming property of the odor adsorbing layer is poor, so it tends to be difficult to contain many odor adsorbers, and a sufficient adsorbing effect may not be obtained.

  Specific examples of commercially available products include NS-241 and NS-231 (amino group-containing compound-supporting inorganic porous material) manufactured by Toagosei Co., Ltd., Dashlight M (Sinanen Zeomic Co., Ltd., amino group-containing compound-supporting inorganic material A porous body) etc. can be used as a suitable odor adsorber in the present invention.

[Inorganic porous material]
In the present invention, any inorganic compound having a large number of pores on the surface can be used as the inorganic porous material, and, for example, inorganic phosphoric acid such as zeolite, silicon dioxide, silicate, activated carbon, titania, calcium phosphate and the like And salts, alumina, aluminum hydroxide, magnesium hydroxide, and mixtures thereof.
In particular, aluminum hydroxide, zeolite, and silicate are preferably applied from the viewpoint of safety and a porous state having a pore size effective for the molecular size and cluster size of the substance to be adsorbed.
In addition, they may have any external shape such as spherical, rod-like, or elliptical, and may have any form such as powdery, massive, granular, etc. From the viewpoint of film forming properties of the odor-adsorbing layer, uniform dispersion in a thermoplastic resin, kneading characteristics, and the like, the powder form is preferred.

Inorganic porous materials having an average particle diameter can be appropriately selected depending on the application, but in the present invention, those having an average particle diameter of 0.01 μm to 10 μm are particularly preferable, and 0.1 μm to 8 μm. Is more preferable, and 1 μm to 7 μm is more preferable.
If the average particle size is smaller than 0.01 μm, aggregation of the odor adsorber tends to occur, and the dispersibility of the odor adsorber in the thermoplastic resin tends to decrease, and the average particle size is smaller than 10 μm. If it is large, the film forming property of the odor adsorbing layer tends to be poor, so it tends to be difficult to contain a large amount of odor adsorbing material, and there is a possibility that a sufficient deodorizing effect can not be obtained.

[Chemical adsorbent]
In the present invention, the chemical adsorbent has a reactive functional group that causes a chemical reaction with an organic substance that dissolves or an odor substance generated by decomposition of the resin during sterilization / sterilization treatment, It is a compound that can be supported on a porous body.
More specifically, functional groups having reactivity to bind to various aldehydes, ketones, carboxylic acids, etc. generated during sterilization / sterilization treatment such as UV irradiation, γ-ray irradiation, EB irradiation, hot pack, boiling etc. It is a compound which it has.
Such compounds include compounds having an amino group, for example, polyamines such as alkylamine and tetramethylene diamine, compounds having a basic functional group such as ethanolamine, piperidine and hydroxyl group, for example, sodium hydroxide, hydroxide Hydroxides such as potassium hydroxide, magnesium hydroxide and iron hydroxide, carbonates such as sodium carbonate, sodium hydrogencarbonate and calcium carbonate, hydrogencarbonates, amide group-containing compounds such as 2-acrylamido-2-methylpropanesulfonic acid, etc. Can be mentioned.

  In the present invention, examples of the chemical adsorbent which exerts an excellent adsorption effect include compounds having an amino group such as polyamines such as ethylene diamine, diethylene triamine, triethylene triamine, tetraethylene pentamine, piperazine and metaphenylene diamine. However, it is not limited to these.

Although the adsorption mechanism with respect to adsorption object substances, such as the eluted organic substance and odorous substance, of an odor adsorbent is demonstrated in more detail using the specific example of Fig.4 (a)-(b), this invention is not limited to these.
For example, when the substance to be adsorbed is an acid-based odorant, as shown in FIG. 4 (a), an odorant absorbent comprising, for example, a compound having a hydroxyl group supported on an inorganic porous material is used as an odorant adsorbent. It can be used. As a result, the carboxyl group and the hydroxyl group undergo a chemical reaction to be bonded, and the substance to be adsorbed is adsorbed.

When the substance to be adsorbed is an aldehyde, as shown in FIG. 4 (b), for example, an odor adsorbent formed by supporting a compound having an amino group on an inorganic porous material is used as the odor adsorbent. Can. As a result, the aldehyde group and the amino group undergo a chemical reaction to be bonded, and the substance to be adsorbed is adsorbed.
Under the present circumstances, by being chemical adsorption, the adsorption target substance once adsorbed does not desorb, and odor adsorption can be performed efficiently.

  Furthermore, unlike a physical adsorbent in which odor and water vapor are adsorbed at the same adsorption site, the chemical adsorbent in the present invention has an odor adsorption ability because the substance to be adsorbed is bound to a specific functional group of the chemical adsorbent. Insensitive to various substances that lower the water content, such as water vapor.

In one embodiment of the present invention, the odor adsorbing layer has a single-layer structure formed using a resin composition obtained by kneading an odor adsorbing member and a low elution polyethylene. Here, the odor adsorbent may be uniformly dispersed in the layer, or may be dispersed with a concentration gradient.
For example, they may be dispersed with an increasing concentration gradient from the inner surface to the outer surface at the time of package formation, and this configuration improves the heat sealability. Conversely, it may be distributed with a decreasing concentration gradient from the inner surface to the outer surface at the time of package formation, and this configuration improves the interlayer adhesion strength.
Furthermore, it may be dispersed with a decreasing concentration gradient from the center in the thickness direction of the odor absorbing layer toward both surfaces, and this configuration improves the heat sealability and the interlayer adhesion strength.
In another embodiment, the odor adsorbing layer may have a multi-layered structure in which two or more layers are laminated, wherein each layer is mainly composed of the type of low elution polyethylene to be a main component, and the odor adsorbing material. It may consist of a resin composition from which a kind and content differ, respectively.

  If the layer thickness of the whole odor adsorption layer is 5 μm or more, film formation is possible, but in order to obtain good film forming property and heat sealability, interlayer adhesion strength and odor adsorption property, 10 μm to 200 μm is preferable.

<Non-odor adsorption layer>
The non-odor adsorbing layer in the present invention is composed of low elution polyethylene or a resin composition containing low elution polyethylene (hereinafter both are also generically described as “resin composition containing low elution polyethylene”). Although it is a layer, it is a layer which does not contain an odor adsorbent.
Furthermore, high elution polyethylene, polypropylene, methyl pentene polymer, acid-modified polyolefin resin, mixtures of these thermoplastic resins, etc. are included within the range that does not inhibit the low elution property and heat sealability of the sealant film. It is possible, but not limited to these resins.

<Formation of odor adsorption layer and non-odor adsorption layer>
(Method of dispersing odor adsorber)
A known or conventional kneading method can be applied as a method of kneading the odor adsorbent and the low elution polyethylene.
It is also possible to mix the odor adsorbent directly with the low elution polyethylene and knead it, or mix the odor adsorbent with the thermoplastic resin at high concentration and then melt knead it to make a master batch, It is also possible to use a so-called master batch method of mixing, melt-kneading with low elution polyethylene at a ratio according to the target content.
0.5 mass% or more and 40 mass% or less are preferable, and, as for the content rate of a hydrophobic zeolite in a masterbatch, 1 mass% or more and 20 mass% or less are more preferable.
0.5 mass% or more and 40 mass% or less are preferable, and, as for the content rate of a chemical adsorbent carrying | support inorganic porous body in a masterbatch, 1 mass% or more and 20 mass% or less are more preferable.
In the case of the master batch method, even a combination of an odor adsorbent and a low elution polyethylene, in which aggregation tends to occur, can be dispersed uniformly.

Under the present circumstances, the thermoplastic resin in a masterbatch does not need to be the same as the low elution polyethylene in an odor adsorption layer, According to the objective, combining the same low elution polyethylene and the kind of other thermoplastic resins Is possible.
For example, if the odor adsorber and the low elution polyethylene are melt mixed in advance, when mixed or melt-kneaded with the low elution polyethylene again, it is homogeneous and has good film forming property, heat sealability, interlayer adhesion strength And it is possible to obtain odor adsorbability.
As thermoplastic resins other than low elution polyethylene in the odor adsorption layer, general purpose non low elution polyethylene, polypropylene, polyolefin resin such as methylpentene polymer and acid-modified polyolefin resin, and mixtures of these resins, etc. However, it is not limited to these resins.
The thermoplastic resin is preferably one having a low elution property comparable to that of the low elution polyethylene in the present invention, but a general-purpose resin is used within a range that does not adversely affect the elution amount of the organic substance from the entire sealant film. It can be used.

(Film forming and laminating method)
In the present invention, the film formation and lamination method of each layer of the sealant film are not particularly limited, and known or conventional film formation methods and lamination methods can be applied.
Laminating the odor-adsorbing layer or the non-odor-adsorbing layer on the other layer, optionally through the adhesive layer, by extrusion coating, or, for example, a plurality of the odor-adsorbing layer and the non-odor-adsorbing layer It can also be formed by coextrusion by an inflation method or a cast method.
In the case of laminating by extrusion coating, first, the resin composition forming the odor absorbing layer and the resin composition forming the non-odor absorbing layer are heated and melted, and the T die is used to expand and stretch in the necessary width direction And extruding in a curtain shape, causing the molten resin to flow down onto the surface to be laminated, and sandwiching it with a rubber roll and a cooled metal roll, thereby forming an odor adsorbing layer or a non-odor adsorbing layer and adhering to the surface to be laminated And stack simultaneously.

  The melt flow rate (MFR) of the low elution polyethylene contained in the odor adsorption layer and the thermoplastic resin contained in the nonodor adsorption layer when laminating by extrusion coating is 0.2 to 50 g / 10 min Is more preferable, and more preferably 0.5 to 30 g / 10 min. In addition, in this specification, MFR is the value measured from the method based on JISK7210.

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.
In the case of using the inflation method, the melt flow rate (MFR) of the low elution polyethylene contained in the odor adsorption layer and the thermoplastic resin contained in the non-odor adsorption layer is 0.2 to 10.0 g / 10 min Is more preferable, and more preferably 0.2 to 9.5 g / 10 min.
If the MFR is less than 0.2 g / 10 min, or more than 10.0 g / 10 min, it tends to be inferior in terms of processing suitability.
Alternatively, the odor-adsorbing layer and the non-odor-adsorbing layer formed in advance may be laminated via the 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 and laminate an adhesive layer between the sealant film and the base film, and between each layer of the sealant film.
The adhesive layer may consist of an adhesive or an optional anchor coating.
The adhesive may be a thermosetting type, an ultraviolet ray curing type, an electron beam curing type, etc., and may be any form such as an aqueous type, a solution type, an emulsion type, a dispersion type, etc. The adhesion mechanism may be any of chemical reaction type, solvent volatilization type, heat melting type, heat pressure type and the like.

The adhesive layer may be a layer formed of an EC (extrusion coat) layer, an adhesive for dry lamination, an adhesive for non-solvent lamination, or the like.
As components for forming such an adhesive layer, polyvinyl acetate adhesives such as polyvinyl acetate and vinyl acetate-ethylene copolymer, copolymers of polyacrylic acid with polystyrene, polyester, polyvinyl acetate and the like An acrylic adhesive based on polyacrylic acid, a cyanoacrylate based adhesive, an ethylene copolymer based adhesive composed of a copolymer of ethylene and a monomer such as vinyl acetate, ethyl acrylate, acrylic acid or methacrylic acid, a cellulose based adhesive, Polyurethane based adhesives, polyester based adhesives, polyamide based adhesives, polyimide based adhesives, polyolefin based adhesives such as LDPE, amino resin based adhesives composed of urea resin or melamine resin, phenol resin based adhesives, epoxy based resins Adhesives, reactive (meth) acrylic adhesives, chloroprene rubber, nitrile rubber, Styrene - butadiene made of rubber or the like elastomeric adhesive, a silicone adhesive, an alkali metal silicate, inorganic adhesive or the like made of a low-melting glass.

  As an anchor coat agent, anchor coat agents, such as organic titanium type, an isocyanate type, a polyethylene imine type, an acid modified polyethylene type, a polybutadiene type, can be used, for example.

When the adhesive layer is laminated by extrusion coating, although not particularly limited, the adhesive can be formed by extrusion coating on the layer to be adhered.
In the extrusion coating, first, the adhesive is heated and melted, and expanded and stretched in the necessary width direction with a T-die to be extruded like a curtain, and the melt is allowed to flow down onto the layer to be adhered, and the rubber roll and cooling are performed. By sandwiching with the metal roll, the formation of the adhesive layer and the adhesion to the layer to be adhered and the lamination are simultaneously performed.

In the case of using an adhesive for dry lamination as the adhesive layer, the adhesive dispersed or dissolved in a solvent is applied on one layer and dried, and the other layer to be adhered is stacked and then laminated at 30 to 120 ° C. The adhesive is cured and laminated by aging at several hours to several days.
When an adhesive for non-solvent lamination is used, the adhesive itself is applied onto the layer without being dispersed or dissolved in a solvent and dried, and the other adhesion target layer is stacked and laminated, and then at 30 to 120 ° C. The adhesive is cured and laminated by aging for several hours to several days.

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

<Packaging material>
The packaging material for liquid content packaging of the present invention comprises a layer comprising the sealant film for liquid content packaging of the present invention, and may comprise only the sealant film, and if necessary, A material layer, a functional material layer, an adhesive layer, etc. can also be provided. A well-known thing can be laminated | stacked and used for a base material layer, a functional layer, and an adhesive bond layer by a well-known method.

<Packaging body>
The liquid content package of the present invention is formed, for example, by packaging the liquid content packaging packaging material of the present invention, and is the packaging material folded so that the surfaces having good heat sealability face each other? Alternatively, two sheets may be stacked, and the peripheral edge portion thereof may be, for example, side seal type, two side seal type, three way seal type, four side seal type, envelope stuck seal type, combined palm stuck seal type (pillow seal type), crimped seal type It can manufacture by heat-sealing by heat seal forms, such as a flat bottom seal type, a square bottom seal type, and a gusset type.
As a method of heat sealing, for example, a bar seal, a rotating roll seal, a belt seal,
Known methods such as impulse seal, high frequency seal, ultrasonic seal and the like can be applied.

<Liquid content>
In the present invention, the liquid content refers to all liquids such as seasoning liquids such as drinking water, juices, infusion for drips, soy sauce, sauces, soups, honey, sauces, dressings and the like.

The detail of the raw material used for the Example is as follows.
[Low elution polyethylene and high elution polyethylene]

[Odor adsorber]
Kesmon NS-241: manufactured by Toagosei Co., Ltd., an inorganic porous material carrying an amino group-containing compound. Average particle size 3.5 μm.
Dashlight M: manufactured by Sinanen Zeomic Co., Ltd., amino group-containing compound-supporting inorganic porous material. Average particle size 6 to 7 μm.
[Hydrophobic zeolite]
Mizuka sieves EX-122: manufactured by Mizusawa Chemical Industry Co., Ltd. SiO ₂ / AL ₂ O ₃ molar ratio = 32/1, average particle size = 2.5 to 5.5 μm.
-Shilton MT100: manufactured by Mizusawa Chemical Industry Co., Ltd. SiO ₂ / AL ₂ O ₃ molar ratio = 100/1, the average particle size = 3～4.5Myuemu.
-Shilton MT400: manufactured by Mizusawa Chemical Industry Co., Ltd. SiO ₂ / AL ₂ O ₃ molar ratio = 400/1, the average particle size = 5 to 7 .mu.m.
-Shilton MT 2000: manufactured by Mizusawa Chemical Industry Co., Ltd. SiO ₂ / AL ₂ O ₃ molar ratio = 2000/1, the average particle size = 2-4 [mu] m.
-Shilton MT-8000: manufactured by Mizusawa Chemical Industry Co., Ltd. SiO ₂ / AL ₂ O ₃ molar ratio = 8000/1, average particle size = 0.8 μm.

[Master batch adjustment]
The master batch was prepared as follows.
(Adjustment of master batch 1)
Melt blend of Ultozex 1520 L, which is LLDPE of low elution polyethylene, and Quesmon NS-241, which is an inorganic porous material supported with a chemical adsorbent, in the following ratio, to obtain master batch 1 (MB1).
Wurtzex 1520L 90 parts by mass Kesmon NS-241 10 parts by mass (adjustment of master batches 2 to 9)
According to the composition of Table 2, the thermoplastic resin and the odor adsorbent or the hydrophobic zeolite were melt-blended in the same manner as master batch 1 to obtain master batches 2 to 9 (MB 2 to 9).

Example 1
The master batch 1 obtained above, the master batch 6, and the wortazex 1520 L were dry-blended in the following ratio to obtain a mixture for an odor adsorption layer.

Master batch 1 4.18 parts by mass Master batch 6 12.52 parts by mass Urtozex 1520 L 83.3 parts by mass And the mixture obtained above and urtozex 1520 L for a non-odor adsorption layer are made at 160 ° C. by inflation It laminated | stacked by film | membrane, and obtained the sealant film of 3 layer structure which becomes a non-odor adsorption layer 10 micrometers / odor adsorption layer 30 micrometers / non-odor adsorption layer 10 micrometers.

Next, the film forming property, the adsorption effect, the heat sealability, and the pinhole resistance were evaluated.
The detailed configuration of the laminate and the evaluation results are shown in Table 3.

<Examples 2 to 18, Comparative Example 2>
According to the formulations described in Tables 3-5, as in Example 1, a mixture for the odor absorbing layer was obtained, and a sealant film was made and evaluated.
The detailed configuration of the laminate and the evaluation results are shown in Tables 3 to 5.

Comparative Example 1
An inflation film was formed at 160 ° C. by using Evolue SP 2020 of LLDPE which is a high elution polyethylene to obtain a sealant film (50 μm).
Then, it evaluated similarly to Example 1. The configuration of the laminate and the evaluation results are shown in Table 5.

<Evaluation>
[Film forming property]
The appearance of was observed and evaluated sensually. Evaluation criteria are as follows.
○: Film formation is possible without wrinkles or bumps on the film.
X: A large number of wrinkles and bumps occur on the film, making film formation difficult.
[Heat sealability]
The sealant film produced by the example and the comparative example, PET film (12 μm in thickness, Espet T4102: manufactured by Toyobo Co., Ltd.), and aluminum foil (7 μm in thickness, manufactured by Toyo Aluminum Co., Ltd.) are dry laminated Adhesive (RU004 / H-1: manufactured by Rock Paint Co., Ltd., coating amount: 3.5 g / m ^{2 for} each adhesive layer, drying temperature 70 ° C.), and bonded, PET film / adhesive layer / aluminum foil / An adhesive layer / sealant film laminate was produced.

Next, this laminate is cut into 10 cm × 10 cm, folded in half so that the sealant portion of the laminate is in contact and stacked, 1 cm × using a heat seal tester (manufactured by Tester Sangyo Co., Ltd .: TP-701-A) A 10-cm area heat-sealed sample was prepared (the end was not heat-sealed and not adhered, but in a bifurcated state). The sample was cut into strips of 15 mm width, and each of the bifurcated ends was mounted on a tensile tester to measure the tensile strength (N / 15 mm).
Heat sealing condition temperature: 160 ° C
Pressure: 1 kgf / cm ²
Time: 1 second Tensile strength test condition Test speed: 300 mm / min Load range: 50 N
Pass / fail judgment ○: More than 30 N / 15 mm, pass.
X: It is less than 30 N / 15 mm, and it fails.

[Pinhole resistance]
The sealant film produced in the example and the comparative example is cut into A4 size (30 cm × 21 cm) and bent with a Gelboflex tester (BE-1005 manufactured by Tester Sangyo Co., Ltd.), 30 cm × 21 cm of each sample after bending The number of pinholes generated in the plane of was counted.
Temperature: 23 ° C
Gelbo bending frequency: 5000 times

[Fill water TOC increase concentration]
The pouch bag (15 cm x 44 cm) was produced using each sealant film obtained by the Example and the comparative example, and UV irradiation sterilization treatment was previously given to the inner surface of each laminated body.
Then, 1000 g of water at 65 ° C. (distilled water for high performance liquid chromatography, Junsei Chemical Co., Ltd.) is hot-packed into each obtained package to make a package liquid fill, and stored at 35 ° C. for 2 weeks. The TOC concentration of the filling water was measured using a TOC-L all-organic carbon meter manufactured by Shimadzu Corporation.

Subsequently, the TOC concentration was similarly measured for water before filling.
The TOC increase concentration in each package was determined from the following equation.
TOC increase concentration = Filled water TOC concentration after storage-TOC concentration of water before filling TOC concentration of water before filling: 0.02 ppm
UV irradiation sterilization condition UV wavelength: 253.7 nm
Irradiation time: 10 seconds
Temperature: 25 ° C

<Result Summary>
The package of all the examples using low elution polyethylene showed good film-forming property, seal strength, puncture strength, and increased concentration of TOC.

  Further, Examples 1 to 12, 15 to 24 and 27 using low elution polyethylene excellent in pinhole resistance are Examples 13, 14 and 25 using low elution polyethylene inferior to pinhole resistance. , And 26 showed excellent pinhole resistance.

  The comparative example 1 which does not have an odor adsorption layer had large TOC increase concentration. Moreover, although the TOC increase density can be reduced, the comparative example 2 which contains an odor adsorbent more than 15 mass% showed the result to which film forming property, seal strength, and pinhole resistance are inferior.

1. Sealant film 2. Non-odor adsorption layer 3. Odor adsorption layer 3a. Odor adsorption layer (concentration a)
3b. Odor adsorption layer (concentration b)

Claims (15)

It is a sealant film for liquid content packaging which has an odor adsorption layer at least,
The sealant film is formed of a resin composition containing low elution polyethylene,
The odor adsorbing layer is formed of a resin composition containing low elution polyethylene and an odor adsorbing material,
The concentration of elution TOC contained in the film made of the low elution polyethylene is 1.5 ppm or more and 250 ppm or less,
The odor adsorber comprises hydrophobic zeolite having a SiO ₂ / Al ₂ O ₃ molar ratio of 30/1 to 10000/1.
Sealant film for liquid content packaging.   The sealant film for liquid content packaging according to claim 1, wherein the odor adsorbent further comprises a chemical adsorbent-supporting inorganic porous material. The sealant film for liquid content packaging according to claim 1 or 2 whose density of said low elution polyethylene is 0.90 g / cm ³ or more and 0.94 g / cm ³ or less.   The sealant film for liquid content packaging according to any one of claims 1 to 3, wherein the low elution polyethylene is LLDPE.   The liquid content package according to any one of claims 1 to 4, wherein the low elution polyethylene is one or more selected from the group consisting of C4-LLDPE, C6-LLDPE, and C8-LLDPE. Sealant film.   The number of pinholes generated after 5000 times Gelvoflex at 23 ° C. of the 50 μm-thick film consisting of the low elution polyethylene alone is 0, or 1 or more and 160 or less. A sealant film for liquid content packaging according to any one of the preceding claims.   The said odor adsorber is melt-kneaded in a mass ratio of the odor adsorber / thermoplastic resin in advance in a ratio of 0.5 / 99.5 to 40/60 with a thermoplastic resin. A sealant film for liquid content packaging according to any one of the preceding claims.   The sealant film for liquid content packaging according to claim 7, wherein the melt flow rate of the thermoplastic resin is 0.2 to 10.0 g / 10 min.   The sealant film for liquid content packaging according to any one of claims 1 to 8, wherein the content of the odor adsorbent is 0.3% by mass or more and 15% by mass or less in the total sealant film. .   The sealant film for liquid content packaging according to any one of claims 1 to 9, wherein the sealant film has a non-odor adsorption layer on the surface and / or the back surface of the odor adsorption layer. .   The chemical adsorption agent according to any one of claims 1 to 10, wherein the chemical adsorbent has a functional group having reactivity with one or more selected from the group consisting of aldehydes, ketones, and carboxylic acids. The sealant film for liquid content packaging as described in a section.   The sealant film for liquid content packaging according to any one of claims 1 to 11, wherein the chemical adsorbent has an amino group.   The liquid content packaging according to any one of claims 1 to 12, wherein the content of the hydrophobic zeolite is 0.3% by mass or more and 15% by mass or less in all the odor absorbing layers. Sealant film.   The packaging material for liquid contents which was produced using the sealant film for liquid contents packaging in any one of Claims 1-13.   A liquid contents package formed from the liquid contents packaging material according to claim 14.

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