JP6950288B2 - Laminates for sterilization and sterilization, packaging materials using the laminates, and packaging - Google Patents

Description

The present invention comprises an odor adsorption layer having the ability to adsorb and deodorize odors generated from a laminate during sterilization and sterilization treatments such as UV irradiation, hot pack, boil, γ-ray irradiation, and EB irradiation, and a base material. The present invention relates to a packaging material having a layer and having excellent odor resistance changeability, and a packaging material using the packaging material.

As a packaging material, a packaging material containing an odor adsorbent that adsorbs an odor has been proposed (Patent Document 1). In such packaging materials, odor adsorbents such as synthetic zeolite and activated carbon are 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.

Japanese Patent No. 2538487

The present invention solves the above-mentioned problems, is excellent in manufacturing suitability, and is used for sterilization such as UV irradiation, hot pack, boil, γ-ray irradiation, EB irradiation, and decomposition of the resin constituting the package during sterilization. It exerts a high adsorption effect on the generated odor and deodorizes it, and it is possible to efficiently adsorb the odor without desorbing the odor once adsorbed, so the odor adsorption ability does not decrease and it is long-term. It is an object of the present invention to provide a packaging material which exhibits a high adsorption effect over a period of time and has excellent odor resistance changeability to a filling material, and a packaging material using the packaging material.

As a result of various studies, the present inventors have made a packaging material for sterilization and sterilization treatment, which comprises a laminate having an odor adsorbing layer, wherein the odor adsorbing layer carries a chemical adsorbent on an inorganic porous body. It has been found that a packaging material for sterilization and sterilization treatment, which comprises a resin composition containing an odor adsorbent, and a packaging material comprising the same, achieve the above-mentioned object.

The present invention is characterized by the following points.
1. 1. It is a laminate for sterilization and sterilization treatment having at least an odor adsorbing layer and a base material layer, and the odor adsorbing layer is a thermoplastic resin containing an odor adsorbent.
The odor adsorbent is an inorganic porous body or an inorganic porous body carrying a chemical adsorbent.
Laminate for sterilization and sterilization.
2. The laminate for sterilization and sterilization treatment according to 1 above, wherein the base material layer is a thermoplastic resin.
3. 3. The sterilization according to 1 or 2 above, wherein the sterilization and sterilization treatment is one or more sterilization and sterilization treatments selected from the group of UV irradiation, γ-ray irradiation, EB irradiation, hot pack, and boil. , Laminate for sterilization.
4. The laminate for sterilization or sterilization according to any one of 1 to 3 above, which further has a functional material layer between the base material layer and the odor adsorption layer.
5. The laminate for sterilization and sterilization treatment according to 4 above, wherein the functional material layer is one or more layers selected from the group consisting of a gas barrier layer, a light-shielding layer, and a strength layer.
6. The laminate for sterilization or sterilization according to any one of 1 to 5 above, wherein the content of the odor adsorbent is 0.3% by mass or more and 15% by mass or less in all the odor adsorbent layers.
7. The laminate for sterilization and sterilization according to any one of 1 to 6 above, wherein the thermoplastic resin of the odor adsorption layer is a polyethylene resin.
8. The laminate for sterilization and sterilization treatment according to 7 above, wherein the polyethylene-based resin contains low-density polyethylene.
9. The laminate for sterilization and sterilization treatment according to 7 above, wherein the polyethylene-based resin contains two types of linear low-density polyethylene and low-density polyethylene.

10. The laminate for sterilization and sterilization according to any one of 1 to 9 above, wherein the odor adsorption layer further has a linear low-density polyethylene layer on the front surface and / or the back surface of the odor adsorption layer.
11. The laminate for sterilization and sterilization treatment according to 9 above, wherein the odor adsorbent and the low-density polyethylene are melt-mixed in advance.
12. The base material layer contains one or more selected from the group consisting of unstretched nylon film, stretched nylon film, PET film, linear low-density polyethylene film, and low-density polyethylene film.
It is composed of one layer or two or more layers.
When it is composed of two or more layers, it is a layer having the same composition or a layer having a different composition.
The laminate for sterilization and sterilization treatment according to any one of 1 to 11 above.
13. The laminate for sterilization and sterilization treatment according to any one of 1 to 12 above, wherein the chemical adsorbent has a reactive functional group.
14. The sterilization and sterilization treatment according to 13 above, wherein the reactive functional group is a functional group having reactivity with one or more selected from the group of aldehydes, ketones, and carboxylic acids. Laminated body.
15. The laminate for sterilization and sterilization treatment according to 13 above, wherein the reactive functional group is an amino group.
16. A packaging material produced by the laminate for sterilization and sterilization according to any one of 1 to 15 above.
17. A packaging body for liquid filling formed from the packaging material according to 16 above.

Since the laminate for sterilization and sterilization treatment of the present invention has an odor adsorption layer having a specific configuration, the laminate is subjected to sterilization and sterilization treatment of UV irradiation, γ-ray irradiation, EB irradiation, hot pack, boil, etc. It has the effect of efficiently adsorbing the odor generated by the decomposition of the resins that make up the product over a long period of time, and suppresses changes in the odor of the filled contents when a packaging package for filling is produced using it as a packaging material. can do. Therefore, the laminate for sterilization and sterilization treatment of the present invention is suitable as a packaging material for foods, pharmaceuticals and medical products to be sterilized and sterilized, and is particularly suitable as a packaging material for packaging liquids.

Further, the laminate for sterilization and sterilization treatment of the present invention has an odor containing a base material layer made of a thermoplastic resin having excellent pinhole resistance and a certain piercing strength, and a thermoplastic resin and an odor adsorbent. Since it has a laminated structure with an adsorption layer, it can be used as a packaging material having high heat-sealing property and odor adsorption property, as well as pinhole resistance and constant piercing strength.
Further, in the present invention, since the odor adsorbent has a chemical adsorbent supported on the inorganic porous body, the odor adsorbent is efficiently adsorbed without desorbing the odorous substance once adsorbed by the effect of chemical adsorption. be able to. Further, unlike the physical adsorbent in which odor and water vapor are adsorbed on the same adsorption site, the chemical adsorbent in the present invention has an odor adsorbing ability because the odorous substance binds to a specific functional group of the chemical adsorbent. It is not easily affected by various substances that reduce it, such as water vapor.
Furthermore, the laminate of the present invention is excellent in productivity, and the raw material cost and the number of manufacturing steps are reduced in the production thereof.

It is a schematic cross-sectional view which shows an example about the layer structure of the laminated body for sterilization and sterilization processing of this invention. It is a schematic cross-sectional view which shows an example about the layer structure of the laminated body for sterilization and sterilization processing of this invention. It is a schematic cross-sectional view which shows an example about the layer structure of the laminated body for sterilization and sterilization processing of this invention. It is a figure which shows the adsorption mechanism of an odor adsorbent with respect to an odor substance.

The sterilizing and sterilizing laminate, packaging material, and packaging of the present invention 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 the laminate for sterilization and sterilization of the present invention>
FIG. 1 is a schematic cross-sectional view showing an example of the layer structure of the laminate for sterilization and sterilization treatment of the present invention. As shown in FIG. 1, the sterilization / sterilization treatment laminate of the present invention is formed by laminating a base material layer 1 and an odor adsorption layer 2, and in some cases, laminating via an adhesive layer. It may be.

Alternatively, as shown in FIG. 2, an additional functional material layer 3, for example, a gas barrier film or a metal foil, may be provided between the base material layer 1 and the odor adsorption layer 2.

Further, as shown in FIG. 3, the odor adsorption layer 2 may have a multi-layer structure of two layers 2a and 2b. Here, the type of the main resin constituting the odor adsorbing layer and the content of the odor adsorbent may be different for each layer. For example, one of the two layers, for example, the layer 2a on the side facing the base material layer 1 or the functional material layer 3, is made of a heat-sealing resin containing an odor adsorbent, and is the innermost layer 2b. However, it may be made of a heat-sealing resin that does not contain an odor adsorbent. Since the layer 2b does not contain an odor adsorbent, the sealing strength of the package can be improved.
On the contrary, the layer 2a does not contain the odor adsorbent, and the layer 2b contains the odor adsorbent, so that the interlayer adhesion strength can be improved.

Further, although not shown, the odor adsorption layer 2 may be composed of three layers or more. Here, similarly to the above, the type of the main resin and the content of the odor adsorbent may be different for each layer. For example, by forming a three-layer structure of a layer containing no odor adsorbent (outer layer), a layer containing an odor adsorbent (intermediate layer), and a layer not containing an odor adsorbent (outer layer), the sealing strength and the interlayer adhesive strength can be obtained. Can be improved.

<Odor adsorption layer>
[Thermoplastic resin that is the main constituent of the odor adsorption layer]
In the present invention, the thermoplastic resin that is the main constituent of the odor adsorption layer is not particularly limited as long as it has a heat-sealing property, but a polyolefin-based resin is preferably used, and a known or commercially available polyolefin having a heat-sealing property is used. A based resin can be used.

Examples of such polyolefin-based resins include low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear (linear) low-density polyethylene (LLDPE), and ethylene-vinyl acetate common weight. Combined, polyethylene (PE) -based such as ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methylmethacrylic acid copolymer, ethylene-propylene copolymer, etc. Examples thereof include, but are not limited to, resins, polypropylene, methylpentene polymers, acid-modified polyolefin-based resins, and mixtures of these resins. In particular, in the state of containing an odor adsorbent, in order to exhibit UV irradiation, γ-ray irradiation, EB irradiation, hot pack, stability against boil, excellent heat sealability and odor adsorbability, polyethylene resin, polypropylene, etc. are used. It is preferably used, and the polyethylene-based resin more preferably contains low-density polyethylene, linear low-density polyethylene, or the like, and most preferably contains linear low-density polyethylene. Further, those containing a small amount of additives such as antioxidants and antiblocking agents in the resin can also be applied.

[Odor adsorbent]
In the present invention, the odor adsorbing layer is mainly composed of a thermoplastic resin and contains an odor adsorbent. Here, the odor adsorbent has a function of adsorbing odorous substances generated from the package during UV irradiation, γ-ray irradiation, EB irradiation, sterilization of hot packs, boil, etc., and sterilization treatment, and is an inorganic porous body. A chemical adsorbent is carried on the surface. As a supporting method, a known or conventional supporting method can be applied. For example, the inorganic porous body may be impregnated with a solution containing a chemical adsorbent described below and dried to support the inorganic porous material. can.

In the present invention, by containing the odor adsorbent in which the chemical adsorbent is supported on the inorganic porous body in the odor adsorbent layer, the odor adsorbing ability per unit mass of the chemical adsorbent can be significantly enhanced, and the odor adsorbent can be contained in the package. The content of the chemical adsorbent and the odor adsorbent can be reduced. As a result, high sealing strength can be obtained, and excellent heat-sealing properties and film-forming properties required for packaging materials can be maintained.

If the amount of the odor adsorbent added is 0.1% by mass or more in the total odor adsorbing layer, a sufficient odor adsorbing effect can be exhibited, but a good odor adsorbing effect as a package is obtained. In order to obtain the above, it 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 producing the laminate and to achieve good heat-sealing property, the amount of the odor adsorbent added is preferably 15% by mass or less, preferably 10% by mass. The following is more preferable.

Further, the odor adsorbent may have an arbitrary outer shape such as a spherical shape, a rod shape, or an elliptical shape, and may have any shape such as a powder shape, a lump shape, or a granular shape. From the viewpoint of uniform dispersion in the thermoplastic resin, kneading characteristics, etc., the powder form is preferable.

As the odor adsorbent, an odor adsorbent having an arbitrary average particle size can be appropriately selected depending on the intended use, but in the present invention, an odor adsorbent having an average particle size of 0.01 μm to 10 μm is particularly preferable. When the average particle size is smaller than 0.01 μm, the odor adsorbent tends to aggregate, the dispersibility of the odor adsorbent in the thermoplastic resin tends to decrease, and the average particle size is larger than 10 μm. If it is large, the film-forming property of the odor adsorbent layer is inferior, so that it tends to be difficult to add many odor adsorbents, and there is a possibility that a sufficient deodorizing effect cannot be obtained. Here, the average particle size is a value measured by a dynamic light scattering method.
As specific examples of commercially available products, NS-241 and NS-231 (an odor adsorbent in which an amino group is supported on an inorganic porous body) manufactured by Toagosei Co., Ltd. are used as suitable odor adsorbents in the present invention. be able to.

[Inorganic porous material]
In the present invention, any inorganic compound having a large number of pores on its surface can be used as the inorganic porous body, and for example, inorganic phosphoric acid such as zeolite, silicon dioxide, silicate, activated charcoal, titania, and calcium phosphate. Examples include salts, alumina, aluminum hydroxide, magnesium hydroxide, and mixtures thereof. In particular, it is preferable to apply aluminum hydroxide, zeolite, or silicate from the viewpoint of having a porous state having a pore size effective with respect to the molecular size and cluster size of the substance to be adsorbed and from the viewpoint of safety. Further, these may have any outer shape such as spherical, rod-shaped, elliptical, etc., and may be in any form such as powdery, lumpy, granular, etc., but carry a chemical adsorbent to form an odor adsorbent. After that, the powdery state is preferable from the viewpoints of film forming property of the odor adsorption layer, uniform dispersion in the thermoplastic resin, kneading characteristics, and the like.

As the inorganic porous body, an arbitrary average particle size can be appropriately selected depending on the intended use, but in the present invention, an average particle size of 0.01 μm to 10 μm is particularly preferable. When the average particle size is smaller than 0.01 μm, the odor adsorbent tends to aggregate, the dispersibility of the odor adsorbent in the thermoplastic resin tends to decrease, and the average particle size is larger than 10 μm. If it is large, the film-forming property of the odor adsorbent layer tends to be inferior, so that it tends to be difficult to add many odor adsorbents, and there is a possibility that a sufficient deodorizing effect cannot be obtained. Here, the average particle size is a value measured by a dynamic light scattering method.

[Chemisorbent]
In the present invention, the chemical adsorbent has a reactive functional group that chemically reacts with an odorous substance generated by decomposition of a resin during sterilization or sterilization, and is supported on the inorganic porous body. The compound to be obtained. More specifically, a functional group having reactivity to bind to various aldehydes, ketones, carboxylic acids and the like generated during UV irradiation, γ-ray irradiation, EB irradiation, sterilization of hot packs, boil and the like, and sterilization treatment. It is a compound that has.

Examples of such a compound include a compound containing an amino group, for example, a polyamine such as alkylamine and tetramethylenediamine, and a compound having a basic functional group such as ethanolamine, piperidine and a hydroxyl group, for example, sodium hydroxide and hydroxide. Hydroxide such as potassium, magnesium hydroxide, iron hydroxide, carbonate such as sodium carbonate, sodium hydrogencarbonate, calcium carbonate, hydrogen carbonate, amide group-containing compound such as 2-acrylamide-2-methylpropanesulfonic acid, etc. Can be mentioned.

In the present invention, examples of the chemical adsorbent exhibiting a particularly excellent deodorizing effect include compounds having an amino group such as polyamines such as ethylenediamine, diethylenetriamine, triethylenetriamine, tetraethylenepentamine, piperazine and metaphenylenediamine. However, it is not limited to these.

The mechanism for adsorbing an odor adsorbent to an odorous substance will be described in more detail with reference to the specific examples of FIGS. 4A to 4B, but the present invention is not limited thereto.
For example, when the odorous substance is an acid-based odorous substance, as shown in FIG. 4A, as the odor adsorbent, for example, an odor adsorbent obtained by supporting a compound having a hydroxyl group on an inorganic porous body is used. be able to. As a result, the carboxyl group and the hydroxyl group cause a chemical reaction to bond with each other, and the odorous substance is adsorbed.

When the odorous substance is an aldehyde, as shown in FIG. 4B, for example, an odor adsorbent in which a compound having an amino group is supported on an inorganic porous body can be used as the odor adsorbent. .. As a result, the aldehyde group and the amino group cause a chemical reaction to bond with each other, and the odorous substance is adsorbed.

[Formation of odor adsorption layer]
In one aspect of the present invention, the odor adsorbing layer is a single-layer structure formed by using a resin composition obtained by kneading an odor adsorbent and a thermoplastic resin. Here, the odor adsorbent may be uniformly dispersed in the layer, or may be dispersed with a concentration gradient. For example, it may be dispersed from the inner surface to the outer surface at the time of forming the package with an increasing concentration gradient, and this configuration improves the heat sealability. On the contrary, it may be dispersed from the inner surface to the outer surface at the time of forming the package with a decreasing concentration gradient, and this configuration improves the interlayer adhesive strength. Further, the odor adsorbing layer may be dispersed from the central portion in the thickness direction toward both surfaces with a decreasing concentration gradient, and this configuration improves the heat sealability and the interlayer adhesion strength.

In still another embodiment, the odor adsorbing layer may have a multi-layer structure in which two or more layers are laminated, and each layer is made of a resin composition in which the amount of the odor adsorbent added is different. You may. In this configuration, there may be a layer made of only a thermoplastic resin having heat-sealing property and interlayer adhesion strength without containing an odor adsorbent.
Although film formation is possible if the thickness of the entire odor adsorption layer is 5 μm or more, it is preferably 10 μm to 200 μm in order to obtain good film formation property, heat sealability, interlayer adhesion strength and odor adsorption property.

As a method of kneading the odor adsorbent and the thermoplastic resin, a known or conventional kneading method can be applied. For example, after mixing the thermoplastic resin and the odor adsorbent, melt-kneading is performed to prepare a master batch in which the odor adsorbent is dispersed in the thermoplastic resin, and this is again combined with the thermoplastic resin according to the compounding ratio. By the so-called master batch method of mixing and melt-kneading, even an odor adsorbent or a thermoplastic resin in which aggregation is likely to occur can be uniformly dispersed. At this time, the thermoplastic resin in the masterbatch and the thermoplastic resin at the time of redispersion do not have to be the same, and the types of the thermoplastic resin can be combined according to the purpose.

For example, if an odor adsorbent and low-density polyethylene are melt-mixed in advance, when they are mixed or melt-kneaded again with linear low-density polyethylene, they are homogeneous and have good film-forming property, heat-sealing property, and interlayer adhesion. It is possible to obtain strength and odor adsorption.

In the present invention, the laminating method for forming the odor adsorption layer is not particularly limited, and a known or conventional film forming method can be applied, but the resin composition for forming the odor adsorption layer is optionally via an adhesive layer. , A layer to be laminated by extrusion coating on a surface to be laminated such as a base film or a gas barrier film, or, for example, a plurality of thermoplastic resin layers not containing an odor adsorbent and a layer containing an odor adsorbent. Can be formed by coextrusion by the inflation method or the casting method.
Here, as the thermoplastic resin of the thermoplastic resin layer that does not contain an odor adsorbent, the same thermoplastic resin as that of the odor adsorbent layer can be used, and linear low-density polyethylene is particularly preferable.

In the extrusion coating, first, the resin composition forming the odor adsorbent layer and the resin composition forming the thermoplastic resin layer containing no odor adsorbent are heated and melted, and then in the width direction required by the T-die. By expanding and stretching, extruding into a curtain shape, flowing the molten resin onto the surface to be laminated, and sandwiching it between a rubber roll and a cooled metal roll, a layer containing an odor adsorbent and a thermoplastic not containing an odor adsorbent. The resin layer is formed, adhered to the surface to be laminated, and laminated at the same time. When laminated by extrusion coating, the melt flow rate (MFR) of the thermoplastic resin contained in the layer containing the odor adsorbent and the thermoplastic resin layer not containing the odor adsorbent is 0.2 to 50 g / 10 minutes. It is preferably 0.5 to 30 g / 10 minutes. If the MFR is less than 0.2 g / min or 50 g / min or more, it is not effective in terms of processing suitability.

For example, when the inflation method is used, the melt flow rate (MFR) of the thermoplastic resin contained in the layer containing the odor adsorbent and the thermoplastic resin layer not containing the odor adsorbent is 0.2 to 4.0 g / 10 minutes. It is preferably 0.2 to 3.0 g / 10 minutes. If the MFR is less than 0.2 g / 10 minutes or 4.0 g / 10 minutes or more, it tends to be inferior in terms of processing suitability. In this specification, MFR is a value measured by a method based on JIS K7210.

Alternatively, the layer containing the odor adsorbent formed in advance and the thermoplastic resin layer not containing the odor adsorbent may be laminated via the adhesive layer by dry lamination, non-solvent lamination, sand lamination or the like.
Here, the stacking order of the layer containing the odor adsorbent and the thermoplastic resin layer not containing the odor adsorbent may be the front surface (the outermost surface of the laminate), and the back surface (the inner side surface of the laminate). It may be present, or both sides (both front and back surfaces) of the layer containing the odor adsorbent may be a thermoplastic resin layer containing no odor adsorbent.

<Base layer>
In the present invention, various materials can be applied to the base material layer depending on the type of contents to be packaged, mechanical strength, chemical resistance, solvent resistance, manufacturability, etc. required for physical distribution. It is preferable to use a thermoplastic resin.
Examples of the type of resin include polyethylene-based resin, polypropylene-based resin, cyclic polyolefin-based resin, fluorine-based resin, polystyrene-based resin, acrylonitrile-styrene copolymer (AS resin), and acrylonitrile-butadiene-styrene copolymer (ABS). Resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyethylene terephthalate (PET), polyester resin such as polyethylene naphthalate, polyamide resin such as various nylons, polyimide Various resins such as based resins, polyamideimide-based resins, polyarylphthalate-based resins, silicone-based resins, polysulfone-based resins, polyphenylene sulfide-based resins, polyether sulfone-based resins, polyurethane-based resins, acetal-based resins, and cellulose-based resins. A containing film can be used.

Among the films containing the above resins, in the present invention, the base material layer is preferably an unstretched nylon film, a stretched nylon film, a PET film, a linear low-density polyethylene film, or a low-density polyethylene film, and is particularly polyethylene-based. A linear low-density polyethylene film or a low-density polyethylene film, which is a resin film, is preferable, and a film containing a linear low-density polyethylene is most preferable.

The base material layer preferably contains a film using one or more kinds of resins selected from the above, and even if it is composed of one layer, it is composed of two or more layers having the same composition or different compositions. You may be.

In the present invention, the base material layer may be a single layer or a multilayer film formed by a film forming method such as an extrusion method, a cast forming method, a T-die method, a cutting method, or an inflation method. The thickness of the base material layer can be appropriately determined by those skilled in the art depending on the packaging application, but is preferably 6 to 150 μm, more preferably 9 to 130 μm.

Further, the base material layer in the laminate of the present invention has workability, heat resistance, weather resistance, mechanical properties, dimensional stability, antioxidant properties, slipperiness, releasability, flame retardancy, and resistance of the laminate. Various reforming resins, plastic compounding agents, additives and the like can be added for the purpose of improving and modifying moldiness, electrical properties, strength and the like. In this case, these additives may be arbitrarily contained in the base material layer from a very small amount to several tens of mass% depending on the purpose. In the present invention, as general additives, colorants such as lubricants, cross-linking agents, antioxidants, ultraviolet adsorbents, light stabilizers, fillers, antistatic agents, lubricants, antiblocking agents, dyes and pigments. Etc. can be arbitrarily contained.

Furthermore, the base material layer can also have resin layers of various materials in order to impart high elasticity and pinhole resistance. For example, it can have layers of 6 nylon, 66 nylon, 6/66 nylon copolymer, low density polyethylene, EVOH, etc., and it is particularly preferable to have a layer of 6/66 nylon copolymer.

<Functional material layer>
In the present invention, when the laminate has a functional material layer, a known or commercially available film having gas barrier property, light-shielding property, and high strength is included in the functional material layer as the gas barrier layer, light-shielding layer, and strength layer. be able to. Specifically, the film includes a resin such as PET, polybutylene terephthalate, polyethylene naphthalate, polyamide, polyimide, polyvinyl alcohol, an ethylene / vinyl alcohol copolymer, and a resin film of a mixture thereof, and the above-mentioned gas barrier property. A vapor-deposited film such as a silica vapor-deposited film or an aluminum oxide vapor-deposited film, a metal foil such as an aluminum foil, or the like can be used on at least one surface of the film, but the present invention is not limited thereto. Among the above films, it is preferable to use a silica-deposited film, an aluminum oxide-deposited film, or an aluminum foil from the viewpoint of excellent gas barrier properties. Further, in particular, by using an aluminum foil, it is possible to impart a light-shielding property and suppress deterioration of the laminate and the filler due to light irradiation, and it can be preferably used. Further, when a film having high strength is applied, the laminated body can be adjusted so as to have an appropriate piercing strength according to the purpose, and the film specifically includes PET and polybutylene. A vapor-deposited film such as terephthalate, a silica-deposited film or an aluminum oxide-deposited film can be used.
In the present invention, the thickness of the functional material layer is preferably about 5 to 30 μm.

<Adhesive layer>
In the present invention, an adhesive layer is provided between the layers in the odor adsorption layer, the layers in the base material layer, the layers in the functional material layer, and the layers between the base material layer, the functional material layer, and the odor adsorption layer. It is also possible to provide and stack.
In one aspect of the present invention, the adhesive layer may be a layer composed of an EC (extrusion coat) layer, a dry laminating adhesive, a non-solvent laminating adhesive, or the like.

When the adhesive layer is laminated using an extrusion coat, the adhesive layer or the adhesive composition can be formed by extrusion coating on the layer film to be adhered, although not particularly limited. In the extrusion coating, first, the adhesive or the adhesive composition is heated and melted, expanded and stretched in the required width direction with a T-die, extruded in a curtain shape, and the melt flows down onto the layer film to be adhered. By sandwiching it between a rubber roll and a cooled metal roll, the adhesive layer is formed, and the adhesive layer is adhered to and laminated on the film to be adhered at the same time.

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

These adhesives may be a thermosetting type, an ultraviolet curing type, an electron beam curing type, or the like. Examples of such an adhesive include a polyvinyl acetate-based adhesive such as polyvinyl acetate and a vinyl acetate-ethylene copolymer, and a polyacrylic acid composed of a copolymer of polyacrylic acid and polystyrene, polyester, polyvinyl acetate and the like. Ethylene copolymer adhesives, cyanoacrylate adhesives, ethylene copolymer adhesives consisting of copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid, cellulose adhesives, and polyurethane adhesives. , Polyester adhesive, Polyamide adhesive, Polygon adhesive, Polyethylene adhesive, Amino resin adhesive composed of urea resin, melamine resin, etc., Phenolic resin adhesive, Epoxy adhesive, Reactive type (meta) ) Acrylic adhesives, chloroprene rubbers, nitrile rubbers, elastomer adhesives made of styrene-butadiene rubbers, silicone adhesives, alkali metal silicates, inorganic adhesives made of low melting point glass and the like can be mentioned.

Further, the adhesive may be in any form such as an aqueous type, a solution type, an emulsion type and a dispersed type, and the properties thereof may be any form such as a film / sheet form, a powder form and a solid form. Further, the bonding mechanism may be in any form such as a chemical reaction type, a solvent volatilization type, a heat melting type, and a hot pressure type.

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.

In another aspect of the present invention, the layers in the odor adsorption layer, the layers in the base material layer, the layers in the barrier intermediate layer, and the layers between the base material layer, the odor adsorption layer, and the barrier intermediate layer are It may be laminated by sand lamination. In this case, the adhesive layer can be made of any resin that can be melted by heating and applied in an extruder. Specifically, the resins listed as the above-mentioned thermoplastic resins having heat-sealing properties can be preferably used.
In yet another aspect of the present invention, the odor adsorption layer is laminated by extrusion coating on the base film. In this case, the adhesive layer provided between the base film and the odor adsorption layer may be made of any anchor coating agent, for example, an anchor of organic titanium-based, isocyanate-based, polyethyleneimine-based, acid-modified polyethylene-based, polybutadiene-based, or the like. A coating agent can be used.

<Packaging material>
The packaging material of the present invention is obtained by using the above-mentioned laminate as a packaging material.

<Packaging body>
The packaging body of the present invention is made by making a bag of the packaging material of the present invention, and the laminated film is bent or the laminated film is bent so that the surface (heat seal surface) on the side where the odor adsorbing layer is close to the outside faces. The sheets are overlapped, and the peripheral ends thereof are, for example, side seal type, two-way seal type, three-way seal type, four-way seal type, envelope-attached seal type, gassho-attached seal type (pillow-seal type), fold-attached seal type, and flat bottom. It can be produced by heat-sealing in a heat-sealing form such as a seal type, a square bottom seal type, or a gusset type.
In the present invention, as the heat sealing method, known methods such as bar sealing, rotary roll sealing, belt sealing, impulse sealing, high frequency sealing, and ultrasonic sealing 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.

Details of the raw materials used in the examples are as follows.
[Odor adsorbent]
-Kesmon NS-241: Inorganic porous body having an amino group. Made by Toagosei Co., Ltd.
-Kesmon NS-231: Inorganic porous body having an amino group. Made by Toagosei Co., Ltd.
KD-311: Inorganic porous body having an amino group. Made by Rasa Industries, Ltd. Average particle size 10 μm or less.
-Dashlite M: An inorganic porous body having an amino group. Made by Sinanen Zeomic Co., Ltd., with an average particle size of 6 to 7 μm.
KD-211: Silicon dioxide particles carrying metal oxides that are not reactive with aldehydes and acidic substances. Rasa Industries, Ltd. Particle size 10 μm or less.
[LDPE]
-Novatec LC600A: Made by Japan Polyethylene Corporation. MFR = 7.0 g / 10 minutes. -Novatec LC520 (manufactured by Japan Polyethylene Corporation) MFR = 3.6 g / 10 minutes.
[LLDPE]
-SP2020: Made by Prime Polymer Co., Ltd. MFR = 2.3g / 10 minutes.

<Preparation of resin composition>
According to the formulation shown in Table 1, each odor adsorbent and Novatec LC600A, which is a thermoplastic resin LDPE, are mixed, further kneaded at a kneading temperature of 110 ° C. to 180 ° C., and cooled to obtain pellets of the resin compositions A to G. Obtained.
Then, according to the formulation shown in Table 2, the pellets of the resin compositions A to G and the pellets of SP2020, which is a thermoplastic resin LLDPE, were dry-blended to obtain mixtures A1 to A4 and B1 to G1.

<Example 1>
SP2020, which is an LLDPE, and the mixture A1 obtained above are laminated by an inflation film forming to obtain a film-like odor adsorbing layer having a three-layer structure of an LLDPE layer of 10 μm / an odor adsorbent-containing layer of 30 μm / an LLDPE layer of 10 μm. rice field. Next, the odor-adsorbing layer and a three-layer film (Multitron, manufactured by Tamapoli Co., Ltd.) having a PE layer of 25 μm, a non-stretched nylon layer of 20 μm, and a PE layer of 25 μm as a base material were combined with EC (Extrew). Laminated under the following conditions by John coating), and has a 6-layer structure (total thickness 135 μm) consisting of PE layer 25 μm / unstretched nylon layer 20 μm / PE layer 25 μm / EC layer 15 μm / LLDPE layer 10 μm / odor adsorbent-containing layer 30 μm / LLDPE layer 10 μm. ) Was obtained, and the obtained laminate was used as a packaging material to evaluate film forming property, deodorizing effect, heat sealing property, piercing strength, and pinhole resistance.
Table 3 shows the structure of the laminated body and the evaluation results.

[Laminating conditions]
Extrusion temperature: 330 ° C
Adhesive layer material: LDPE (Novatec LC520)
Adhesive layer thickness: 15 μm

<Examples 2 to 7>
According to the configuration of Table 3, the mixture A1 was replaced with the mixture A2, A3, B1 to E1 in the same manner as in Example 1 to obtain a film-like odor adsorbing layer having a three-layer structure, and then EC. To obtain a film-like laminate having a 6-layer structure (total thickness of 135 μm), and using the obtained laminate as a packaging material, film-forming property, heat-sealing property, piercing strength, pinhole resistance, The deodorizing effect was evaluated. Table 3 shows the structure of the laminated body and the evaluation results.

<Example 8>
LLDPE layer 25 μm / unstretched nylon layer 20 μm by inflation method using LLDPE (SP2020), nylon (UBE5033B, polyamide 6/66 copolymer manufactured by Ube Kosan Co., Ltd.) and the above mixture A3. / LLDPE layer 35 μm / odor adsorbent-containing layer 30 μm / LLDPE layer 10 μm A five-layer structure (total thickness 120 μm) was obtained, and the obtained laminate was used as a packaging material for film-forming and heat-sealing properties. , Puncture strength, pinhole resistance, and deodorant effect were evaluated. Table 3 shows the structure of the laminated body and the evaluation results.

<Comparative Examples 1 to 5>
According to the configuration of Table 3, the same operation as in Example 1 was carried out to obtain a laminate by EC, and the obtained laminate was used as a packaging material to obtain film-forming property, heat-sealing property, and piercing strength. The pinhole resistance and deodorant effect were evaluated. Table 3 shows the structure of the laminated body and the evaluation results.
However, in Comparative Example 4, the heat-sealing property was inferior, and the heat-sealing property was inferior. Therefore, a sufficient laminate could not be obtained, and the evaluation of the deodorizing effect was stopped.
<< Evaluation of deodorant effect >>
Each of the packaging materials obtained in Examples and Comparative Examples was subjected to UV irradiation sterilization treatment, and a packaging body was prepared with a pouch (13 cm × 17 cm). Then, 100 ml of water (natural water from the Alps, manufactured by Suntory Co., Ltd.) was filled in each of the obtained packages to prepare a package liquid filler, and after storage at 10 ° C. for 1 week, the sensory evaluation of the filled water was carried out. bottom.

[UV irradiation sterilization treatment conditions]
UV wavelength: 253.7 nm
Irradiation time: 1 minute
Temperature: 25 ° C

[Film formation]
The appearance of the odor-adsorbing film was observed and evaluated sensually. 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 the film.

[Heat sealability]
The laminates produced in Examples and Comparative Examples are cut into 10 cm × 10 cm pieces, folded in half so that the sides of the odor adsorption layers face each other (arbitrarily for Comparative Examples 1 and 2), and overlapped with each other, and heat-sealed tester (tester industry). A sample in which a region of 1 cm × 10 cm was heat-sealed was prepared using TP-701-A) (the end portion was not heat-sealed and adhered, and was bifurcated). This sample was cut into strips with a width of 15 mm, and each bifurcated end was mounted on a tensile tester to measure the tensile strength (N / 15 mm).

Heat seal condition Temperature: 160 ℃
Pressure: 1 kgf / cm ²
Time: 1 second Tensile strength test conditions Test speed: 300 mm / min Load range: 100 N
Pass / Fail Result ○: 30N / 15mm or more, passed.
X: Less than 30 N / 15 mm and failed.

[Puncture strength]
The laminates prepared in Examples and Comparative Examples were cut to prepare strips of 120 mm × 80 mm, which were used as test samples. The puncture strength of each test sample was measured using a tensile compression tester (SA-1150 manufactured by ORIENTEC) by a method according to JIS Z 1707 1997.

[Pinhole resistance]
The laminates produced in Examples and Comparative Examples were cut into A4 size (30 cm × 21 cm), bent with a gelboflex tester using the outermost layer surface of each laminate as a test surface, and then 30 cm × 21 cm of each sample. The number of pinholes generated in the area was counted.
Temperature: 23 ° C
Gerbo flexion count: 5000 times

[Deodorant effect]
The deodorant effect was evaluated by sensory evaluation. The evaluation indexes are as follows. There were 10 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 untreated UV sterilization

<Summary of results>
From this result, the packages of Examples 1 to 8 showed good odor adsorption effect and deodorant effect, but Comparative Examples 1 to 5 did not show a sufficient deodorant effect, and Comparative Example 4 was sufficient. No film-forming property and heat-sealing property could be obtained.

1. 1. Base material layers 2, 2a, 2b. Odor adsorption layer 3. Functional material layer

Claims (15)

A laminate for sterilization and sterilization treatment, which has at least an odor adsorption layer and a base material layer and is used as a packaging material for packaging liquid contents.
The sterilization and sterilization treatment is UV irradiation.
The odor adsorbing layer is a thermoplastic resin containing an odor adsorbent.
The odor adsorbent is an inorganic porous body carrying a chemical adsorbent.
The chemisorbent is a compound having a functional group having a reactivity that binds to aldehydes, ketones, and carboxylic acids.
The inorganic porous body has an average particle size of 0.01 μm to 10 μm, and has an average particle size of 0.01 μm to 10 μm.
The content of the odor adsorbent is 0.3% by mass or more and 15% by mass or less in the odor adsorbing layer.
Laminate for sterilization and sterilization. The laminate for sterilization and sterilization according to claim 1, wherein the base material layer is a thermoplastic resin. The laminate for sterilization and sterilization according to claim 1 or 2, wherein a functional material layer is further provided between the base material layer and the odor adsorption layer. The laminate for sterilization and sterilization according to claim 3, wherein the functional material layer is one or more layers selected from the group consisting of a gas barrier layer, a light-shielding layer, and a strength layer. The laminate for sterilization and sterilization according to any one of claims 1 to 4, wherein the thermoplastic resin of the odor adsorption layer is a polyethylene-based resin. The laminate for sterilization and sterilization according to claim 5, wherein the polyethylene-based resin contains low-density polyethylene. The laminate for sterilization and sterilization according to claim 5, wherein the polyethylene-based resin contains two types of linear low-density polyethylene and low-density polyethylene. The sterilization and sterilization treatment according to any one of claims 1 to 7, wherein the odor adsorption layer further has a linear low-density polyethylene layer on the front surface and / or the back surface of the odor adsorption layer. Laminated body. The laminate for sterilization and sterilization according to claim 7, wherein the odor adsorbent and the low-density polyethylene are melt-mixed in advance. The base material layer contains one or more selected from the group consisting of unstretched nylon film, stretched nylon film, PET film, linear low-density polyethylene film, and low-density polyethylene film.
It is composed of one layer or two or more layers.
When it is composed of two or more layers, it is a layer having the same composition or a layer having a different composition.
The laminate for sterilization and sterilization according to any one of claims 1 to 9. The laminate for sterilization and sterilization treatment according to any one of claims 1 to 10, wherein the chemical adsorbent has a reactive functional group. The sterilization and sterilization treatment according to claim 11, wherein the reactive functional group is a functional group having reactivity with one or more selected from the group of aldehydes, ketones, and carboxylic acids. Laminated body for. The laminate for sterilization and sterilization according to claim 11, wherein the reactive functional group is an amino group. A packaging material for packaging a liquid content produced by the laminate for sterilization and sterilization according to any one of claims 1 to 13. A package for liquid filling formed from the packaging material according to claim 14.

Images