JP6524613B2 - Sheet and package - Google Patents

Description

  The present invention relates to a sheet and a package.

 BACKGROUND ART Conventionally, paper, synthetic resin sheets or films, vapor deposited films, laminates with synthetic resin films, aluminum packaging and the like have been used as packaging materials for pharmaceuticals, medical products, foods, beverages and the like. When used in the above applications, the content protection property, in particular, the barrier property against water vapor and oxygen is required, and a high level of barrier property is required to protect the contents in the long term ing.

 Examples of materials satisfying both the moisture permeation resistance and the oxygen permeation resistance as described above include a vapor deposited film and an aluminum package, which may be used as a specific package such as a pouch shape, but may be molded. It is difficult to form it into an arbitrary shape with a machine or the like, and its use is limited.

 On the other hand, as a form of a packaging container, after forming in a container using a sheet made of a synthetic resin as a bottom material, a packaging form heat-sealed with a film of a lid material and aluminum foil is often used. As such a packaging material, a sheet made of a synthetic resin is often used, and in particular, a polyolefin resin has excellent moldability, high productivity, chemical resistance, moisture permeation resistance, etc. It is used in the industrial field.

 However, although polyolefin-based resins are excellent in moisture permeation resistance, they have insufficient gas permeation resistance to oxygen gas and the like. As a result, the contents may have problems such as oxidation, deterioration, rot or rust.

 In order to solve this problem, ethylene-vinyl alcohol copolymer, resins with high oxygen gas permeability such as nylon are used, but when using these resins alone, oxygen barrier due to humidity The problem is that the property is reduced and the water vapor barrier property is poor, and it has been generally used by laminating with a resin having high water vapor resistance (for example, Patent Document 1). However, the barrier properties of these constitutions are inferior to those of the above-mentioned vapor deposited film and aluminum, and they can be formed into any form, and a packaging material having higher barrier properties has been desired.

Japanese Examined Patent Publication No. 06-15227

  An object of the present invention is to provide a sheet and a package which have extremely low permeability to water vapor and oxygen, can be formed into a container, and exhibit high barrier properties even after retort and sterilization.

Such an object is achieved by the present invention of the following (1) to (7).
(1) A sheet having at least a water vapor barrier layer, an oxygen barrier layer, and a surface layer, and the water vapor transmission amount at 40 ° C., 90% RH is 0.15 g / m ² · day or less, 25 ° C., 60 A sheet characterized in that the oxygen permeation amount at% RH is 0.2 cc / m ² · day or less.
(2) The sheet according to (1), wherein the water vapor barrier layer has a water vapor transmission rate of 0.5 g / m ² · day or less at 40 ° C. and 90% RH.
(3) The sheet according to (1) or (2), wherein the ratio of the thickness of the oxygen barrier layer to the entire thickness of the sheet is 5% or more and 30% or less.
(4) The sheet according to any one of (1) to (3), wherein the water vapor barrier layer contains 10% by weight or more and 40% by weight or less of an inorganic filler based on the entire water vapor barrier layer.
(5) The sheet according to any one of the above (1) to (4), wherein the thickness of the sheet is 500 μm or more and 1500 μm or less.
(6) A package comprising the sheet according to any one of the above (1) to (5).
(7) The package according to (6), wherein the package comprises an oxygen barrier layer, a water vapor barrier layer, and a surface layer in this order from the inner surface side.
(8) The package includes, from the inner surface side, the first surface layer, the first water vapor barrier layer, the oxygen barrier layer, the second water vapor barrier layer, and the second surface layer in this order The package as described in said (6) which is comprised including.

  According to the present invention, it is possible to provide a high barrier sheet against water vapor and oxygen and a high barrier package which protects the contents from the permeation of water vapor and oxygen, and prolonging the expiration date and stability of the contents. be able to.

It is a sectional view showing an example of a sheet concerning one embodiment of the present invention. It is sectional drawing which shows an example of the package which concerns on one Embodiment of this invention.

  Hereinafter, the sheet of the present invention will be described in detail.

The sheet of the present invention is a sheet having at least a water vapor barrier layer, an oxygen barrier layer, and a surface layer, and the water vapor transmission amount at 40 ° C., 90% RH is 0.15 g / m ² · day or less, The oxygen permeation amount at 60 ° C. and 60% RH is 0.2 cc / m ² · day or less.

The sheet of the present invention protects the contents from external moisture when formed into a package by the water vapor transmission rate at 40 ° C., 90% RH being 0.15 g / m ² · day or less. Function is sufficient, and the contents weak to water vapor can be stored for a long time. In addition, when the content contains a liquid, it is possible to prevent water evaporation from the content, and the liquid concentration of the content can be maintained for a long time.

 As a result, in the conventional package, the barrier function is low, and it becomes possible to extend the period of use of the product which has been disposed of in a short period of time, and it is possible to reduce the amount of waste. Therefore, the total cost of the product and the amount of discarding of the product and the package can be suppressed.

The water vapor transmission rate at 40 ° C. and 90% RH of the sheet of the present invention is not particularly limited as long as it is 0.15 g / m ² · day or less, but is 0.1 g / m ² · day or less Is preferably, and more preferably 0.05 g / m ² · day or less. When the water vapor transmission amount at 40 ° C. and 90% RH of the sheet of the present invention is in the above range, the above-mentioned effect can be more remarkably exhibited.

In addition, when the sheet of the present invention is formed into a package because the oxygen permeation amount at 25 ° C. and 60% RH is 0.2 cc / m ² · day or less, the content is oxygen from the outside It is possible to sufficiently protect the contents from oxidation, deterioration, rot, and rusting of contents, and it is possible to store contents which are weak to oxygen for a long time. In addition, since the contents can be stored for a long time without using an antioxidant, it is possible to save time and effort for enclosing the antioxidant when using as a package, and to prevent accidental ingestion of the antioxidant. It becomes possible.

Incidentally, the sheet of the present invention, 25 ° C., the oxygen transmission rate at 60% RH is not more than 0.2cc / m ² · day, but are not limited to, the following 0.15cc / m ² · day Is preferably 0.1 cc / m ² · day or less. When the oxygen permeation amount at 25 ° C. and 60% RH of the sheet of the present invention is in the above range, the above effect can be more remarkably exhibited.

 Hereinafter, the sheet of the present invention will be described in detail based on the embodiment shown in the drawings.

  The sheet | seat 100 which concerns on this invention has the water vapor | steam barrier layer 1, the oxygen barrier layer 2, and the surface layer 4 so that it may illustrate in FIG.

 Each component of the seat 100 will be described in detail below.

<Steam barrier layer 1>
The water vapor barrier layer 1 prevents the permeation of water vapor in the sheet 100 and protects the contents while suppressing the permeation of water vapor to the oxygen barrier layer 2 when the sheet 100 is formed into a package.

 As a result, it is possible to suppress the decrease in the oxygen barrier property due to the moisture absorption of the oxygen barrier layer 2.

 In addition, since the cleavage of the intermolecular hydrogen bond of the resin constituting the oxygen barrier layer 2 is prevented by the water vapor and the molecular gap of the resin constituting the oxygen barrier layer 2 can be maintained in a narrow state, the oxygen barrier layer 2 is a water vapor barrier Sex can be expressed.

Here, in the water vapor barrier layer 1, the water vapor transmission rate at 40 ° C., 90% RH is preferably 0.5 g / m ² · day or less, and more preferably 0.4 g / m ² · day or less preferable.

 When the water vapor transmission amount at 40 ° C. and 90% RH of the water vapor barrier layer 1 is equal to or less than the above upper limit, the water vapor transmission amount to the oxygen barrier layer 2 decreases, and the oxygen barrier property by the moisture absorption of the oxygen barrier layer 2 The reduction is suppressed, and the oxygen barrier layer 2 can further exhibit water vapor barrier properties.

 As shown in FIG. 1, the sheet 100 preferably has the water vapor barrier layer 1 on both sides of the oxygen barrier layer 2, whereby the above effect can be more remarkably exhibited.

 The resin constituting the water vapor barrier layer 1 may be, for example, a polyolefin resin such as polypropylene, polyethylene, high density polyethylene, cyclic olefin polymer, cyclic olefin copolymer, or a halogen atom such as polyvinylidene chloride or polychlorotrifluoroethylene. Resins and those obtained by adding an inorganic filler to these resins, and the like, but from the viewpoint of formability to a sheet, formability to a container, sealability with a lid material, and cost, polypropylene, polyethylene, high density Polyethylene is preferred.

 The water vapor barrier layer 1 preferably contains 10% by weight or more and 40% by weight or less of the inorganic filler with respect to the whole water vapor barrier layer 1. When the water vapor barrier layer 1 contains 10% by weight or more and 40% by weight or less of the inorganic filler with respect to the whole water vapor barrier layer 1, the water vapor barrier property of the water vapor barrier layer 1 is improved, and the water vapor barrier as a whole sheet Sex improves dramatically.

 The content of the inorganic filler contained in the water vapor barrier layer 1 is more preferably 20% by weight or more and 30% by weight with respect to the whole water vapor barrier layer 1.

 If the content of the inorganic filler contained in the water vapor barrier layer 1 is less than the above lower limit, the improvement width of the water vapor barrier property is small, and if it is more than the upper limit, the film forming property of the sheet and the package Formability may be degraded.

 Moreover, as an inorganic filler contained in the water vapor barrier layer 1, for example, layered silicates such as talc, mica, kaolin, clay, bentonite, silica, calcium carbonate, magnesium carbonate, calcium carbonate, calcium sulfate, magnesium sulfate, barium sulfate, Glass fillers, glass fibers, glass beads, titanium oxide, aluminum oxide, iron, zinc, aluminum etc. may be mentioned, but from the viewpoint of improving the barrier property, plate-like and scale-like fillers having a large aspect ratio are preferable, and talc is particularly preferable. , Mica is more preferred.

 The thickness of the water vapor barrier layer 1 is not particularly limited, but is preferably 200 μm or more and 650 μm or less, and more preferably 300 μm or more and 500 μm or less. When the thickness of the water vapor barrier layer 1 is at least the lower limit value, the water vapor barrier layer 1 can exhibit sufficient barrier properties, and when the water vapor barrier layer 1 has at most the upper limit value, it is easy to form into a package. Become.

 The ratio of the thickness of the water vapor barrier layer 1 to the entire thickness of the sheet 100 is preferably 40% to 85%, and more preferably 60% to 80%.

 When the ratio of the thickness of the water vapor barrier layer 1 to the entire thickness of the sheet 100 is equal to or more than the lower limit value, it is possible to sufficiently exhibit the water vapor barrier property of the entire sheet.

 By being below the said upper limit, in addition to water vapor barrier property, sufficient oxygen barrier property is securable.

<Oxygen barrier layer 2>
The oxygen barrier layer 2 plays a role in the sheet 100 to exhibit an oxygen barrier property and a water vapor barrier property.

 Examples of the resin constituting the oxygen barrier layer 2 include ethylene-vinyl alcohol copolymer, polyamide, polyvinyl alcohol, polyacrylonitrile, polyvinylidene chloride and the like, and the film forming property with the water vapor barrier layer 1 is mentioned. From the viewpoint of the above, ethylene-vinyl alcohol copolymer and polyamide are preferable. Further, as in the case of the water vapor barrier layer 1, the oxygen barrier layer 2 may contain an inorganic filler.

 The thickness of the oxygen barrier layer 2 is not particularly limited, but is preferably 25 μm or more and 450 μm or less, and more preferably 80 μm or more and 300 μm or less. When the thickness of the oxygen barrier layer 2 is not less than the lower limit value, oxygen barrier property and water vapor barrier property can be sufficiently expressed, and when the thickness is not more than the upper limit value, the container can be easily molded at the time of container formation It can maintain the growth as a sheet.

 The ratio of the thickness of the oxygen barrier layer 2 to the entire thickness of the sheet 100 is preferably 5% or more and 30% or less, and more preferably 8% or more and 25% or less.

 When the ratio of the thickness of the oxygen barrier layer 2 to the entire thickness of the sheet 100 is equal to or more than the lower limit value, it is possible to sufficiently exhibit the oxygen barrier property and the water vapor barrier property.

 Further, when the ratio of the thickness of the oxygen barrier layer 2 to the entire thickness of the sheet 100 is equal to or less than the upper limit value, the ratio of the water vapor barrier layer 1 can be maintained. It can be expressed sufficiently.

<Adhesive layer 3>
The water vapor barrier layer 1 and the oxygen barrier layer 2 can be adhered by the adhesive layer 3. Although it does not specifically limit as resin which comprises the contact bonding layer 3, For example, adhesive resin, such as a maleic anhydride modified olefin, The blend of the water-vapor-barrier layer 1 and the oxygen barrier layer 2, etc. can be mentioned.

<Surface layer 4>
Moreover, the sheet | seat 100 which concerns on this invention has the surface layer 4 in outermost layer.

 In the sheet 100, the surface layer 4 has an effect of reducing variation in strength of the adhesive strength between the sheet 100 and the lid 5.

 As described above, it is preferable that the water vapor barrier layer 1 contains an inorganic filler, but if the layer containing the inorganic filler is present in the outermost layer, the strength variation of the adhesive strength between the sheet 100 and the lid 5 becomes large. And seal strength may be unstable.

 On the other hand, when the surface layer 4 is present, the variation in the adhesive strength between the sheet 100 and the lid 5 is reduced and a sufficient strength can be stably obtained.

 The water vapor barrier layer 1 preferably contains an inorganic filler, but if the layer containing the inorganic filler is present in the outermost layer, the sheet may lose its glossiness. On the other hand, when the surface layer 4 is present, the glossiness of the sheet is sufficient.

 Furthermore, the water vapor barrier layer 1 preferably contains an inorganic filler, but if the layer containing the inorganic filler is present in the outermost layer, when the sheet 100 comes in contact with the die lip at the time of production of the sheet 100, There is a possibility that a deposit may be generated to reduce the productivity.

 On the other hand, when the surface layer 4 is present, the productivity of the sheet 100 is sufficient.

 The resin used for the surface layer 4 is not particularly limited as long as it is a resin adhering to the lid and the water vapor barrier layer 1, but a polyolefin resin is preferable, and polypropylene and polyethylene resins and their blends are particularly preferable. Thereby, the adhesive strength between the sheet 100 and the lid 5 is sufficient.

 The thickness of the surface layer 4 is not particularly limited, but is preferably 25 μm or more and 300 μm or less, and more preferably 50 μm or more and 200 μm or less. When the thickness of the surface layer 4 is not less than the lower limit, stabilization of the seal strength and gloss can be exhibited, and when not more than the upper limit, sufficient water vapor barrier properties can be exhibited. Can.

 The thickness of the surface layer 4 is preferably 5% to 40% with respect to the entire thickness of the sheet 100. Within this range, the effect of expressing the stabilization of the seal strength and the gloss can be obtained while maintaining the water vapor barrier property.

 The sheet 100 preferably has the surface layer 4 on the outermost layers of both sides of the sheet 100.

 The thickness of the sheet 100 is not particularly limited, but is preferably 500 μm or more and 1500 μm or less, and more preferably 800 μm or more and 1200 μm or less. When the thickness of the sheet 100 is not less than the lower limit value, both the water vapor barrier property and the oxygen barrier property can be sufficiently developed. In addition, a good container shape can be maintained when packaging heavy contents. Moreover, when the thickness of the sheet | seat 100 is below the said upper limit, the molding cycle to a container shape can be shortened.

 In addition, the sheet 100 is a crystal nucleating agent, petroleum resin, antistatic agent, ultraviolet light absorber, lubricant, antioxidant, light stabilizer, anti blocking agent, surfactant, dye, and the like within the range that does not impair the basic performance. Additives such as pigments, flame retardants, deodorants, plasticizers, dispersants and the like may be added to one or more layers contained in the sheet 100. By including such a layer, it is possible to prevent the improvement and the deterioration of the productivity of the sheet 100 and the package and to impart the distinguishability.

  Moreover, the sheet | seat 100 which concerns on this invention can be used as a structural member of the package 200 by shape | molding and sealing with the cover material 5 so that it may illustrate in FIG. Various methods can be mentioned as a method of producing the package 200 from the sheet 100 according to the present invention, and various methods are not particularly limited. For example, vacuum forming, pressure forming, pressure vacuum forming, plug assist pressure forming, plug assist Vacuum forming, plug-assisted pressure-assisted vacuum forming, plug forming, press forming and the like can be mentioned.

<Production method of sheet>
The method for producing a sheet according to the present invention is not particularly limited, but it is a coextrusion T-die method such as a feed block method or multi manifold method in which a resin as a raw material is melt extruded by several extruders. An air-cooled or water-cooled co-extrusion inflation method and a lamination method may be mentioned. Among them, the method of forming a film by the co-extrusion T-die method is particularly preferable in that it is excellent in thickness control of each layer. As a subsequent process, a dry lamination method, an extrusion lamination method, a hot melt lamination method, a wet lamination method, a thermal (thermal) lamination method, etc., in which single-layer sheets or films forming each layer are laminated using a suitable adhesive A combination of methods is used. Moreover, you may laminate | stack by the method by coating. In addition, when inorganic fillers are used, it is better to use those pre-kneaded by a twin-screw kneader, kneader, Banbury mixer, etc. to prevent sheet performance and contamination due to scattering of inorganic fillers during sheet formation. It is more preferable because it can be

 The package 200 is configured to include the oxygen barrier layer 2, the water vapor barrier layer 1 and the surface layer in this order from the inner surface (surface on the content side of the package) side. preferable.

 Thereby, the fall of oxygen barrier property by moisture absorption of oxygen barrier layer 2 is controlled, the water vapor barrier property of a package body and oxygen barrier property are exhibited to the maximum, and prolongation of the protection period of the contents is attained.

 Further, the package 200 includes, from the inner surface side, the first surface layer, the first water vapor barrier layer, the oxygen barrier layer, the second water vapor barrier layer, and the second surface layer in this order. It is preferable that it is comprised. That is, by providing the water vapor barrier layer 1 on both sides of the oxygen barrier layer, it is possible to prevent the barrier property against gas such as water vapor and oxygen from the outside, and the evaporation of water from the content side.

 The content of the package 200 is not particularly limited as long as it is particularly required to have water vapor barrier properties and oxygen barrier properties, but pharmaceuticals, preparations, infusion preparations, blood preparations, medical devices, foods, beverages, industrial members, Electronic parts, electrical appliances and the like can be mentioned. Moreover, it can be used also as a secondary packaging container of the primary packaging body which packaged the said content. Furthermore, even in contents requiring retort, sterilization and the like, this sheet can be used because it has sufficient heat resistance to withstand.

 Hereinafter, the present invention will be described in detail by way of examples and comparative examples, but the present invention is not limited to the following examples.

 The raw materials used are as follows.

Polypropylene (Sumitomo Chemical Co., Ltd. product number Sumitomo Nobrene FS2011DG2)
Talc (manufactured by Nippon Talc Co., Ltd., part number K-1)
Ethylene-vinyl alcohol copolymer (Kuraray's product number F101A)
Maleic anhydride modified polypropylene (Mitsubishi Chemical Corporation product number ER313 E-1)
Example 1
A resin layer consisting of 70 parts by weight of polypropylene and 30 parts by weight of talc as the water vapor barrier layer 1, a polypropylene modified with an ethylene-vinyl alcohol copolymer as the oxygen barrier layer 2, a maleic anhydride as the adhesive layer, and a polypropylene as the surface layer The sheets were made by coextrusion using. The total thickness of the sheet is 1 mm, and the thickness ratio of each layer is 10 / (surface layer 4 / water vapor barrier layer 1 / adhesive layer 3 / oxygen barrier layer 2 / adhesive layer 3 / water vapor barrier layer 1 / surface layer 4). It was 32.5 / 2.5 / 10 / 2.5 / 32.5 / 10.

(Example 2)
A sheet was prepared in the same manner as in Example 1 except that the water vapor barrier layer 1 of Example 1 was changed to 80 parts by weight of polypropylene and 20 parts by weight of talc.

(Example 3)
A sheet was prepared in the same manner as in Example 1 except that the water vapor barrier layer 1 of Example 1 was changed to 90 parts by weight of polypropylene and 10 parts by weight of talc.

(Example 4)
A sheet was prepared in the same manner as in Example 1 except that the water vapor barrier layer 1 of Example 1 was changed to 60 parts by weight of polypropylene and 40 parts by weight of talc.

(Comparative example 1)
A sheet was prepared in the same manner as in Example 1 except that the water vapor barrier layer 1 of Example 1 was changed to 100 parts by weight of polypropylene.

(Comparative example 2)
A sheet was prepared in the same manner as in Example 1 except that the water vapor barrier layer 1 of Example 1 was changed to 95 parts by weight of polypropylene and 5 parts by weight of talc.

(Comparative example 3)
A monolayer sheet of the water vapor barrier layer 1 used in Comparative Example 1 was produced.

(Evaluation of water vapor barrier properties)
The water vapor barrier property of the obtained sheet was measured in accordance with JIS K 71267129 B method: 40 ° C./90% RH. The results are shown in Table 1.

(Evaluation of oxygen barrier properties)
The oxygen barrier property of the obtained sheet was measured in accordance with JIS K 7126B method: 25 ° C./60% RH. The results are shown in Table 1.

(Evaluation of formability)
After the obtained sheet was vacuum-formed into a cup shape, the state of the molded product was confirmed and judged as follows. The results are shown in Table 1.

 ○: The product can be molded uniformly according to its shape and its appearance is good.

 X: No shape or surface appearance and appearance defect.

(Measurement of weight loss of contents after molding)
The obtained sheet is vacuum-formed into a cup-shaped container, and a bag containing 5 g of distilled water as a PP film (100 μm) is placed in the container, and the container is sealed with an aluminum lid to measure weight. A sample was made. Evaluation of weight loss was conducted under the 40 ° C. environment of the prepared samples. The weight loss was determined according to the following criteria. The results are shown in Table 1.
<Judgment criteria>
A: Small amount of weight loss, and distilled water remaining for 1 year or more B: Distilled water remaining for half a year or more and less than 1 year C: Distilled water remaining for 3 months or more and less than half a year D: Distillation Water disappears in less than 3 months

DESCRIPTION OF SYMBOLS 1 water vapor barrier layer 2 oxygen barrier layer 3 adhesive layer 4 surface layer 5 lid 6 content 100 sheet 200 package body

Claims (4)

A water vapor barrier layer, an oxygen barrier layer, and a surface layer,
The water vapor transmission rate at 40 ° C and 90% RH is 0.15 g / m ² · day or less,
A package comprising a sheet characterized in that the oxygen permeation amount at 25 ° C., 60% RH is 0.2 cc / m ² · day or less,
The package includes, from the inner surface side, a first surface layer, a first water vapor barrier layer, an oxygen barrier layer, a second water vapor barrier layer, and a second surface layer in this order. And
The thickness of the first surface layer and a second surface layer, 25 [mu] m or more state, and are less 300 [mu] m,
The water vapor barrier layer has a water vapor transmission rate of 0.5 g / m 2 · day or less at 40 ° C. and 90% RH . To the total thickness of the sheet, the ratio of the thickness of the oxygen barrier layer is 5% or more, the packaging body according to claim 1 is 30% or less. The package according to claim 1 or 2, wherein the water vapor barrier layer contains 10% by weight or more and 40% by weight or less of an inorganic filler based on the entire water vapor barrier layer. The package according to any one of claims 1 to 3 , wherein the thickness of the sheet is 500 μm or more and 1500 μm or less.

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