JP2004331855A - Resin composition having moisture absorbing function and indicator function, and laminate and package using the same - Google Patents

Abstract

It has been desired to provide a resin composition capable of having an indicator function and a moisture absorbing function while improving the strength physical properties of the composition, and a laminate and a package using the same.
A complex comprising a specific transition metal atom of a cyclopentadienyl derivative or an ethylene-α-olefin copolymer obtained by using a single-site catalyst comprising methylaluminoxane as required for the above metal complex is essential. In a resin composition containing, as a main component, a polyolefin resin such as a component, and at least 1 to 100 parts by weight of an inorganic compound such as zeolite having a moisture absorbing function with respect to 100 parts by weight of the resin, change in color before and after moisture absorption ( Provided is a resin composition having a moisture absorbing function and an indicator function having a color difference of at least 3 (ΔE).
[Selection diagram] Fig. 1

Description

【００６２】
実施例３および比較例５〜７に示すように、樹脂組成物としては吸湿機能を有する為、容器内の湿度を低湿度で維持する事が可能である。また、実施例３では、上述してきたように鮮明な黄色に変色する事からインジケーター機能を有する事も確認されている。一方、強度物性という点でもシングルサイト系エチレン−αオレフィン共重合体の効果が得られており、特にポリオレフィンプラストマー領域の材料を用いる事で、インナー容器のクラックの発生を抑制している事が確認されている。また当然の事ながら比較例７のように吸湿機能を有する無機化合物の配合量が少ないと、吸湿機能を維持できない。
【００６３】
【発明の効果】
本発明の結果から、吸湿器能を有しながらも、吸湿により鮮明な色調変化を有する樹脂組成物を得る事が可能である。また、この樹脂組成物を用いた積層体／包装体も吸湿機能だけでなく、インジケーター機能を有する事が可能である事から、従来の小袋状吸湿剤の添加が必要でなく、かつ内容物の品質確認という意味でも非常に有効である。無機化合物として吸湿剤を用いると容器の吸湿性が認められるようになる。また、従来高含有量の無機化合物を配合した樹脂組成物はその強度物性が問題視されていたが、本材料処方を用いる事で改善させる事も可能である。
【図面の簡単な説明】
【図１】実施例で用いた容器の模式図および開閉に伴う機構である。
【図２】吸湿機能評価時の容器の形状（センサー導入）の模式図である。
【図３】実施例、比較例の吸湿挙動を示すグラフである。
【図４】実施例、比較例の色差変化を示すグラフである。
【符号の説明】
ａ：中空容器外側
ｂ：中空容器内側（インナー容器樹脂組成物層）
ｃ：無機化合物
ｄ：樹脂Ａ
ｅ：キャップ
ｆ：インナー容器／キャップ密封部分
ｇ：湿度センサー
ｈ：湿度センサーとキャップを固定するバインダー部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a resin composition having a moisture-absorbing function and an indicator function, and a laminate and a package using the same, and more specifically, has a clear coloration due to moisture absorption, and has a good moisture-absorbing rate, and thus has excellent moisture-absorbing ability. The present invention relates to a resin composition, a laminate, and a package using the resin composition.
[0002]
[Prior art]
In the field of a package business for packaging various contents, the following contents are required as "packages" or "packaging".
[0003]
(1) "Display effect" such as giving consumers a purchase consciousness and presenting danger
(2) "Content resistance" so that the package is not affected by the filled content itself
(3) "Protection of contents" against external stimuli
These required contents are further subdivided and developed into fine required quality. Among them, protection of contents from oxygen and moisture is particularly noted in terms of "protection of contents". In particular, recently, in various fields such as a food field, an industrial product field, a medical / pharmaceutical field, etc., importance has been placed on protection of contents against oxygen and moisture. As the background, decomposition of the content due to oxidation and alteration of oxygen, and alteration of the content due to moisture absorption and hydrolysis can be mentioned as moisture.
[0004]
Various methods have been studied to prevent the contents from being deteriorated by oxygen or moisture. One of them is to design a package using a material having an oxygen barrier property or a moisture barrier property. In terms of the moisture barrier, for example, a moisture-proof polyolefin-based resin is used, or a film provided with a moisture-proof property by providing a polyvinylidene chloride-based coating layer on these polyolefin, polyester, or polyamide films is most commonly used. It is a target.
[0005]
Packages using these moisture barrier base materials have been widely used in various applications because of their high moisture barrier properties. However, since these moisture barrier base materials use a chlorine-based polymer, alternatives are being studied.
[0006]
In addition, depending on the contents of some parts, slight humidity or moisture in the headspace may cause deterioration, and it is desired to remove not only moisture barrier properties from the outside of the packaging container but also humidity and moisture in the headspace. Needs are coming out.
[0007]
Against this background, extremely moisture-absorbing contents, such as hygroscopic foods, medical or pharmaceutical products, and industrial devices such as electronics devices, use a moisture-absorbing agent such as silica gel or calcium oxide in a nonwoven fabric or a highly permeable packaging material. At present, a packaged small bag-shaped hygroscopic agent is packaged together with these contents that dislike moisture absorption.
[0008]
In particular, silica gel containing cobalt chloride is very often used as a hygroscopic agent that also functions as a humidity indicator that changes from reddish purple to blue purple by utilizing the change in color tone depending on the number of coordination waters of cobalt chloride. However, in the case of the bag-shaped moisture absorbent such as silica gel, there is a recent tendency to remove the bag-shaped moisture absorbent as much as possible due to the problem of accidental ingestion and complicated packaging. Further, the moisture absorbent having the indicator function uses a cobalt compound, and improvement is desired from the viewpoint of safety.
[0009]
In order to solve these problems, a technique has been developed in which various containers are kneaded with a hygroscopic agent to impart hygroscopicity. These techniques are already known techniques. However, the problem of kneading a high-content moisture absorbent is that the strength properties of the container are reduced. A particularly typical example is a moisture absorption container in which a polymer described in Patent Document 1 is mixed with a moisture absorbent. According to the cited document, an injection-molded container is formed by blending a moisture absorbent and a channel structure forming agent with a thermoplastic resin. The mechanism is that the hygroscopic agent is selectively dispersed in the phase composed of the channel structure forming agent, and by utilizing the local concentration distribution and moisture absorption, fine cracks are gradually generated starting from the channel unit portion, and the cracks are generated. Is used as a path for moisture to improve moisture absorption. However, although this container also has a moisture absorbing ability, the occurrence of cracks is a place where there is a concern about the influence on the strength properties of the container.
[0010]
Improvement of the container properties is also an essential item for the resin composition having a moisture absorbing function or a laminate or a package using the same, but the indicator function is necessary in the sense of confirming the persistence and effect of the moisture absorbing function. Function. In particular, when the desiccant reaches its saturated moisture absorbing ability, it naturally does not exhibit the moisture absorbing function. Therefore, it is desired to provide an indicator function in the sense that consumers can visually confirm the quality of the contents, but at present, there is no confirmed package having the indicator function.
[0011]
[Patent Document 1]
US Patent No. 6,214,255
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and while improving the strength properties of the composition, a resin composition capable of having an indicator function and a moisture absorbing function, and a laminate and a packaging using the same. Getting the body.
[0013]
[Means for Solving the Problems]
The present invention has been conceived to overcome the above problems,
According to the first aspect of the present invention, in a resin composition containing a polyolefin resin as a main component and 1 to 100 parts by weight of an inorganic compound having at least a moisture absorbing function with respect to 100 parts by weight of the resin, a change in color before and after moisture absorption ( (Color difference = ΔE) is at least 3 or more, and is a resin composition having a moisture absorbing function and an indicator function.
[0014]
The invention according to claim 2 is the resin composition according to claim 1, wherein the inorganic compound having a moisture absorbing function is a synthetic or natural zeolite.
[0015]
The invention according to claim 3 is characterized in that the polyolefin resin as a main component is a complex composed of a transition metal atom belonging to group III, IV, V, VI, IX or X of the periodic table of a cyclopentadienyl derivative or the metal complex. If necessary, an ethylene-α-olefin copolymer obtained by using a single-site catalyst, comprising methylaluminoxane, is contained as an essential component, and has a moisture absorption function and an indicator function according to claim 1 or 2. Resin composition.
[0016]
According to a fourth aspect of the present invention, there is provided a laminate comprising the resin composition layer according to the first, second, or third aspect.
[0017]
According to a fifth aspect of the present invention, in one of the resin composition layers according to the first, second, or third aspect, polyethylene, ethylene-α-olefin copolymer, polypropylene, propylene-α-olefin copolymer, ethylene- The laminate according to claim 4, wherein a moisture-proof layer such as a cyclic olefin copolymer, an aluminum foil, an aluminum vapor-deposited film, or an inorganic compound vapor-deposited film is provided.
[0018]
According to a sixth aspect of the present invention, there is provided a package formed from the laminate of the fourth or fifth aspect.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail. The resin composition having a moisture absorbing function and an indicator function of the present invention is a resin composition containing a polyolefin resin as a main component and 1 to 100 parts by weight of an inorganic compound having at least a moisture absorbing function with respect to 100 parts by weight of these resins. In particular, the polyolefin resin as the main component is a complex of a cyclopentadienyl derivative comprising a transition metal atom of Group III, IV, V, VI, IX or X of the periodic table, or methyl as required for the metal complex. An essential component is an ethylene-α-olefin copolymer obtained using a single-site catalyst comprising aluminoxane.
[0020]
Various hygroscopic agents can be used in terms of imparting a moisture absorbing function, but synthetic or natural zeolites are preferred in terms of imparting an indicator function. These zeolite-based compounds have been studied to be mixed with various thermoplastic resins because of their high hygroscopic ability. However, when a zeolite-based hygroscopic agent is added to a thermoplastic resin, a phenomenon that the color changes to dark brown due to moisture absorption has been often confirmed. The content is that the composition composed of zeolite and thermoplastic resin can function as an indicator because the color tone changes due to moisture absorption, but the color development is not vivid color, and the resin has deteriorated color tone Thus, there was a problem in developing this composition itself into a package.
[0021]
Therefore, focusing on this phenomenon and conducting a sincere study for the purpose of vividly changing the color tone, the detailed principle is unknown, but the periodic table of cyclopentadienyl derivatives III, IV, V, VI, IX A complex comprising a group X transition metal atom, or a metal aluminoxane as required for the metal complex, in a polyolefin resin containing an ethylene-α olefin copolymer obtained using a single-site catalyst as an essential component, By blending the above synthetic or natural zeolite, it was found that the color changed to vivid yellow after moisture absorption. An index of discoloration can be measured by using a colorimeter, and the color difference (ΔE) before and after moisture absorption is 3 or more. If it is less than 3, it clarifies the indicator.
[0022]
Examples of such a catalyst include a single-site catalyst (Kamminski catalyst) obtained by adding methylaminoxane to bis (cyclopentadienyl) zirconium chloride and a derivative thereof. As the metal, a transition metal belonging to Group IV of the periodic system, such as titanium, zirconium, or hafnium, is used, but not particularly limited thereto. The above catalyst has a structure in which a transition metal is introduced into two bulky cyclopentadienyl groups. However, by using a titanium-based geometrically constrained catalyst, C6, C8, or a higher α-olefin of C9 or more can also be used. It is possible to introduce.
[0023]
The advantages of using a single-site catalyst as well as the color development as an indicator are as follows.
[0024]
(1) The molecular weight distribution is narrow (2) The introduction position of the comonomer is easily controlled.
(3) Since there are many tie molecules existing between the lamellas, they have excellent strength against tearing and the like.
(4) Flexibility can be imparted. (5) Excellent stress cracking resistance.
Further, a resin composition having a density of 0.930 g / cm ³ or less, particularly a density region of 0.850 to 0.925 g / cm ³ , is in the region of polyolefin elastomer or plastomer and contains a high content of an inorganic compound. It is very preferable in terms of the strength physical properties of the rubber.
[0026]
Although the above description relates to the strength properties, an advantage of using the polyolefin elastomer or the plastomer region is a moisture absorption rate of zeolite blended with the thermoplastic resin. Since the polyolefin-based resin is hydrophobic, if a moisture-absorbing agent is added to the resin, the moisture-absorbing rate is reduced. However, by using a polyolefin-based resin having the above density range, moisture easily permeates through the amorphous portion, and it is possible to improve the rate of moisture absorption as compared with the case where a hygroscopic agent is added to a highly crystalline material.
[0027]
Further, the ethylene-α-olefin copolymer using a single-site catalyst has excellent dispersibility of an inorganic compound. In particular, the above density range is still effective. It is very preferable to use this material system in terms of such strength physical properties, flexibility, inorganic compound dispersibility, and moisture absorption rate.
[0028]
If necessary, various additives such as various additives other than those described above, an antioxidant, a flame retardant, a slip agent, an antiblocking agent, and a dispersant may be added.
[0029]
As the production method of these resin compositions, the material of various predetermined compounding amounts set by the required method such as the molding method of the final product and the required moisture absorption capacity, coloring as an indicator, a ribbon mixer, a tumbler mixer, Dry-blending using a Henschel mixer or the like, and using a single-screw extruder, an extruder such as a twin-screw extruder, or a kneader such as a Banbury, using a kneader such as a melting point or higher and 280 ° C or lower, preferably 260 ° C or lower, more preferably 240 ° C or lower. It is obtained by kneading below. At that time, if necessary, the inorganic moisture absorbent may be subjected to a surface treatment with a dispersant such as an olefin wax in advance.
[0030]
The resin composition having the ability to absorb moisture of the present invention can be formed into a laminate using various molding methods such as extrusion lamination molding, extrusion cast molding, inflation molding, injection molding, and direct blow molding. In addition, for a film (such as inflation) obtained by the above-described molding method, a laminate can be obtained by dry lamination, wet lamination, or non-solvent lamination in a later step, and a preform obtained by injection molding is stretched. Although it is possible to form a multilayer stretch blow bottle by blow molding, it is not limited to these molding methods.
[0031]
When the resin composition of the present invention is used as a laminate, it is preferable that at least one layer of the resin composition is provided with a material having a moisture barrier property. These materials include various polyolefin resins such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-α-olefin copolymer, polypropylene resin, propylene-α-olefin copolymer, ethylene-emotion-olefin copolymer, and the like. It is preferable to use a substrate provided with a barrier coat layer such as polyvinylidene chloride, an aluminum foil, an aluminum vapor-deposited film, or a barrier film obtained by depositing silica or alumina on various substrates by a PVD method or a CVD method. By using these barrier layers, it is possible to not only absorb the moisture slightly transmitted through these barrier layers, but also to lower the humidity of the head space of the package.
[0032]
Examples of the laminate are described below. The symbols described in the example of the laminate are described below.
[0033]
A: Polyolefin resin, B: Polyester film, C: Polyvinylidene chloride coat, D: Aluminum foil
Configuration example-1
Layer composition: A / Resin composition having moisture absorption ability Molding method: Extrusion molding, injection molding, blow molding, etc. Applications: Sheets, hollow containers, cups, trays, etc.
Configuration example-2
Layer composition: B / C / adhesive / A / resin composition having hygroscopic ability Molding method: Extrusion / dry lamination, etc. Use: flexible package, lid material
Configuration example-3
Layer composition: B / adhesive / D / adhesive / A / resin composition having hygroscopic ability Molding method: Extrusion / dry lamination, etc. Use: soft package, lid material
Configuration example-4
Layer composition: paper / A / D / adhesive / A / resin composition having hygroscopic ability Molding method: extrusion lamination etc. Use: composite paper container etc.
As described above, the laminates obtained with various configurations can be directly developed into packages for various uses. These examples are not limited to the contents described above, and can be developed into various packaging forms. In addition, by combining these packaging forms, it becomes possible to form a package that absorbs moisture and has a moisture absorbing ability.
[0039]
In addition, the use is not particularly limited, and it can be used for a soft package, a hollow container, a tray or a cup, a composite paper container, and the like.
[0040]
【Example】
Examples of the present invention will be described below, but the present invention is not limited thereto.
[0041]
[Preparation of resin composition: Materials]
The following materials were used.
[0042]
<Thermoplastic resin>
A-1: single-site ethylene-hexene-1 copolymer (MI = 25, flexural modulus 80 MPa, density 0.901 g / cm ³ )
A-2: Homopolypropylene (MI = 30, flexural modulus 1750 MPa, density 0.900 g / cm ³ )
A-3: Multi-site ethylene-octene-1 copolymer MI = 20, flexural modulus 420 MPa, density 0.925 g / cm ³ )
A-4: low density polyethylene (MI = 20, flexural modulus 160 MPa, density 0.915 g / cm ³ )
[0043]
<Inorganic compound>
B-1: Synthetic zeolite B-2: Silica gel containing powdery cobalt chloride
[Preparation of resin composition: production]
A mixture prepared in advance so that the inorganic compound becomes 67 parts by weight (about 40% by weight in terms of% by weight) with respect to 100 parts by weight of the mixture of the thermoplastic resin and the polyolefin-based dispersant is a twin-screw extruder (φ = 30, (L / D = 49) and the compounding was performed at a discharge of 9 kg, 200 ° C. and 50 rpm. The obtained resin composition was subjected to pelletization after air cooling, and used in the molding method described below.
[0045]
[Creation of evaluation sample: Manufacturing]
The confirmation of the indicator function of the resin composition was evaluated by preparing a coextruded cast film having two and three layers. The layer constitution is as follows: support resin layer / resin composition layer of the present invention / support resin layer = 15 μm / 50 μm / 15 μm (processing temperature 220 ° C.). At this time, the support resin layer was selected using a material that can be cast and has good interfacial adhesion with the thermoplastic resin used in the resin composition layer of the present invention. That is, a polyethylene resin was used for polyethylene or an ethylene-α-olefin copolymer, and a polypropylene resin or a low-crystalline ethylene-α-olefin copolymer was used for a polypropylene resin. The obtained multilayer film was subjected to a storage test in an environment of 40 ° C. and 90% RH, and the change in color tone with respect to the amount of absorbed moisture was measured with a colorimeter manufactured by Olympus Corporation.
[0046]
In order to confirm the moisture absorption function of the resin composition, the screw screw type hollow container and the inner container shown in FIG. 1 are separately molded by injection molding (outermost layer: homopolypropylene resin, innermost layer: resin composition of the present invention). And a container integrated in a later step. The shape of the container is a columnar container having a height of 60 mm and a bottom area of about 1250 mm ² (75000 mm ³ ), and the basis weight of the resin composition layer is about 8 g. The outer layer container was formed using a homopolypropylene resin node to have a basis weight of 10 g and a thickness of about 1.5 mm. The container was equipped with a humidity sensor as shown in FIG. 2, and the change in humidity in the container due to the opening of the container was measured by a recorder manufactured by T & D.
[0047]
Further, as can be seen from FIG. 1, it is confirmed that the inner container is deformed by repeatedly opening and closing the cap and the inner container in the moisture absorbing container. This was to maintain the hermeticity of the container, and the breaking behavior of the inner container accompanying the opening operation was evaluated as strength physical properties (number of times of opening and closing: 50 times).
[0048]
[Confirmation of indicator function]
<Example 1>
Using the resin compositions obtained using A-1 and B-1, a co-extruded multilayer film was formed by using an ethylene-α-olefin copolymer having a melt index of 4.0 as a support resin layer. The results are shown in FIGS. 3 and 4.
[0049]
<Example 2>
A-1 and the above-mentioned ethylene-α-olefin were used by diluting the resin composition obtained using A-1 and B-1 with an ethylene-α-olefin copolymer used as a support resin. A co-extruded multilayer film was formed by the method described in Example 1 such that B-1 was 34 parts by weight (about 20% by weight in terms of% by weight) based on 100 parts by weight of the total amount of the copolymer. The results are shown in FIGS.
[0050]
<Comparative Example 1>
It is the same as Example 1 except that A-4 and B-1 were used.
[0051]
<Comparative Example 2>
Example 2 is the same as Example 1 except that A-2 and B-1 were used, and a block polypropylene having a melt index of 6.0 was used as the support resin.
[0052]
<Comparative Example 3>
It is the same as Example 1 except that A-1 and B-2 were used.
[0053]
<Comparative Example 4>
It is the same as Example 1 except that the ratio of B-1 in the composition was 0.5 parts by weight.
[0054]
From FIG. 3, it is confirmed that Examples 1 and 2 and Comparative Examples 1 to 3 have a hygroscopic function because they contain an inorganic compound having a hygroscopic property. Exceeds ΔE> 10 when the final saturation of the moisture absorption function is reached, and even in Example 2 where the blending ratio is approximately half, ΔE> 6. These colors are vivid and clear yellow, and the entire composition can be uniformly changed from white to vivid yellow by moisture absorption.
[0055]
Further, in Example 3 in which ordinary low-density polyethylene was blended, ΔE <1. When a polypropylene resin is blended, ΔE> 10, but the discoloration is dark brown, and it has an indicator function but is accompanied by a problem in appearance.
[0056]
When silica gel containing cobalt chloride was used as shown in Comparative Example 3, when ΔE> 15, the color changed sharply from blue to reddish purple due to moisture absorption, but only the compounded inorganic compound changed color. There was uneven density due to uneven dispersion of the compound, and when viewed microscopically, the inorganic compound itself was discolored, so that the discolored portion appeared granular and was accompanied by poor appearance.
[0057]
[Evaluation of moisture absorption function and strength properties]
<Example 3>
The resin composition used in Example 1 was molded as an inner container. At that time, when the opening operation was repeated 1, 10, 30, 50 times, the conditions of the humidity in the container and the damage of the inner container indicating how much the humidity can be reduced were taken as the container damage, and the following Comparative Examples 5 to 7 were taken as container damage. Table 1 also summarizes them.
[0058]
<Comparative Example 5>
Same as Example 3 except that the composition obtained using A-3 was used.
[0059]
<Comparative Example 6>
Example 3 is the same as Example 3 except that the resin composition used in Comparative Example 2 was molded as an inner container.
[0060]
<Comparative Example 7>
The same as Example 3 except that the resin composition used in Comparative Example 4 was molded as an inner container.
[0061]
[Table 1]

[0062]
As shown in Example 3 and Comparative Examples 5 to 7, since the resin composition has a moisture absorbing function, the humidity in the container can be maintained at a low level. Further, in Example 3, it was also confirmed that it had an indicator function due to its vivid yellow discoloration as described above. On the other hand, the effect of the single-site ethylene-α-olefin copolymer has also been obtained in terms of strength properties, and in particular, by using a material in the polyolefin plastomer region, it is possible to suppress the occurrence of cracks in the inner container. Has been confirmed. Naturally, when the amount of the inorganic compound having a moisture absorbing function is small as in Comparative Example 7, the moisture absorbing function cannot be maintained.
[0063]
【The invention's effect】
From the results of the present invention, it is possible to obtain a resin composition having a clear color tone change due to moisture absorption while having a moisture absorbing function. Further, since the laminate / package using the resin composition can have not only a moisture absorbing function but also an indicator function, it is not necessary to add a conventional pouch-shaped moisture absorbing agent, and It is also very effective in terms of quality confirmation. When a hygroscopic agent is used as the inorganic compound, the hygroscopicity of the container can be recognized. In addition, conventionally, a resin composition containing a high content of an inorganic compound has been regarded as a problem in the strength physical properties, but it can be improved by using the present material formulation.
[Brief description of the drawings]
FIG. 1 is a schematic view of a container used in Examples and a mechanism for opening and closing the container.
FIG. 2 is a schematic diagram of a shape of a container (introducing a sensor) at the time of evaluating a moisture absorption function.
FIG. 3 is a graph showing the moisture absorption behavior of Examples and Comparative Examples.
FIG. 4 is a graph showing color difference changes in Examples and Comparative Examples.
[Explanation of symbols]
a: outside of the hollow container b: inside of the hollow container (resin composition layer of the inner container)
c: inorganic compound d: resin A
e: Cap f: Inner container / cap sealed part g: Humidity sensor h: Binder part fixing the humidity sensor and cap

Claims (6)

In a resin composition containing a polyolefin resin as a main component and 1 to 100 parts by weight of an inorganic compound having at least a moisture absorbing function with respect to 100 parts by weight of the resin, a change in color (color difference = ΔE) before and after moisture absorption is at least 3 or more. A resin composition having a moisture absorbing function and an indicator function. The resin composition having a moisture absorbing function and an indicator function according to claim 1, wherein the inorganic compound having a moisture absorbing function is a synthetic or natural zeolite. The polyolefin resin as a main component is composed of a cyclopentadienyl derivative composed of a transition metal atom of Group III, IV, V, VI, IX, or X of the Periodic Table, or methylaluminoxane as required for the metal complex. The resin composition having a moisture absorbing function and an indicator function according to claim 1 or 2, comprising an ethylene-α-olefin copolymer obtained by using a single-site catalyst as an essential component. A laminate comprising the resin composition layer according to claim 1, 2, or 3. The resin composition layer according to claim 1, 2, or 3, wherein one of polyethylene, ethylene-α-olefin copolymer, polypropylene, propylene-α-olefin copolymer, ethylene-cyclic olefin copolymer, and aluminum foil. 5. The laminate according to claim 4, further comprising a moisture-proof layer such as an aluminum-deposited film, an inorganic compound-deposited film, or the like. A package formed from the laminate according to claim 4.

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