JPH09183454A - Packing for lid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packing for lid which is excellent in packing property, liquid resistance and safe hygiene property, and in addition, has a high oxygen absorbing capability, is excellent in easy-productivity, etc., and can correspond to a long term storage, and can display an excellent performance in quality retention usage. SOLUTION: This packing for lid is constituted in such a manner that the aluminum foil surface of an aluminum foil laminated sheet, for which on a base material, aluminum foil, a deoxidizing resin layer wherein on a resin with an oxygen permeation factor of 200cc.0.1mm/m<2> .day.atm (23 deg.C. 100%RH) or higher, a granular oxygen remover composition which generates the oxygen removing reaction when receiving the feeding of moisture, is dispersed, and a sealing layer with the oxygen permeation degree of 100cc/m<2> .day.atm (23 deg.C, 100%RH) or higher, are laminated in this order, is bonded with a temporary bonding material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a packing for a lid having an oxygen absorbing function, which is used to seal the mouth of a container such as a bottle, a plastic bottle and various other containers such as caps and lids. The packing of the present invention has excellent liquid resistance, and includes juice, liquor, wine, other liquid beverages, salted fish, boiled rice, jam, marmalade, salmon flakes, and other high-moisture foods. It is used for sealing a storage container containing various foods, pharmaceuticals, etc., and is used for maintaining the quality of these articles, which are easily deteriorated by oxygen and are prone to spoilage or deterioration due to propagation of microorganisms.

[0002]

2. Description of the Related Art Conventionally, beverages that are susceptible to oxygen deterioration,
It has been pointed out that foods, pharmaceuticals, and the like have a problem that their quality is deteriorated by oxygen in the container during the storage period. As a means for solving this problem, vacuum packing, nitrogen substitution, etc. are used, but it is difficult to completely remove oxygen in the container, and the quality retention effect is not satisfied. On the other hand, the use of an oxygen scavenger, which has an excellent oxygen removing effect, has been tried, but there is a problem in the loading property due to the pouch form.

Various methods for incorporating an oxygen absorber into the cap and lid of a container have been proposed. JP-A-57-97
Although a packing containing an oxygen scavenger has been proposed for 46, since a powdered oxygen scavenger is used, it is apt to be contaminated during manufacturing and has a sanitary problem. Due to its high properties, a large amount of oxygen penetrates into the container during long-term storage, and the oxygen absorber in the container cannot be fully absorbed, resulting in an increase in the oxygen concentration in the container.

[0004] Japanese Utility Model Laid-Open No. 1-177165 proposes a packing material for a container having a structure of foam / non-breathable film / deoxidizing film / deodorizing film / breathable film. However, the material itself in contact with the mouth of the container is multi-layered and has poor packing properties, and since the deodorizing film and the breathable film are arranged, oxygen transmission is small and a substantial oxygen absorption rate cannot be obtained. was there. Further, although the deoxidizing film itself also uniformly disperses the iron powder and the salt, the probability that the iron powder and the salt are dispersed in the resin and contact with each other is low, and the oxygen absorbing rate of the deoxidizing film itself is small, and the hygroscopic property is Since it is a raw material, foaming due to evaporation of water is unavoidable at the film forming stage, and there is a problem in production. Furthermore, since iron powder is the main ingredient, when applied to liquids, there is a risk that hydrogen will be generated and the hydrogen concentration in the bottle will rise.

Japanese Unexamined Patent Publication (Kokai) No. 7-137761 proposes a container packing material having a structure of foam / non-breathable film / sheet-shaped oxygen scavenger / breathable sheet. However, the process of attaching the sheet-shaped oxygen scavenger / breathable sheet is complicated and the productivity is low, and the liquid resistance of the breathable sheet is limited. There was a problem.

On the other hand, Japanese Patent Laid-Open No. 4-31253 proposes a packing material composed of a base material / temporary adhesive material / aluminum foil / sealing layer as means for sealing the mouth of a container such as a bottle. A method has been proposed in which an electromagnetic wave is applied by an induction heating device to bond and seal the bottle mouth portion and the seal layer. However, nothing is disclosed about imparting an oxygen absorption function. Furthermore, even if a conventional iron powder-based oxygen absorber is simply fixed inside the packing material, it has a small commercial value in terms of shape and when the electromagnetic wave is applied by an induction heating device, the iron content of the oxygen absorber is reduced. There was a problem that the powder was heated and the packaging material for the oxygen absorber broke.

[0007]

The conventional packing is
As mentioned above, even if there is no oxygen absorption function or it has an oxygen absorption function, there is a problem with the oxygen barrier property of the packing cross section, lack of retention of oxygen absorption performance during long-term use, and oxygen absorption rate is small and practical. It is not satisfactory, there is a limit to liquid resistance for liquid applications, and it is also inferior in safety and hygiene and packing properties. It was
The object of the present invention is to solve the above-mentioned problems of the prior art and to have excellent packing properties, liquid resistance, safety and hygiene properties, and also having high oxygen absorption performance, excellent manufacturability, etc. for a long period of time. It is an object of the present invention to provide a packing for a lid that can be stored and exhibits excellent performance for quality preservation applications.

[0008]

The present inventors have completed the present invention as a result of intensive studies in view of the problems of the prior art. That is, according to the present invention, the base material has an aluminum foil and an oxygen permeability coefficient of 200 cc · 0.1 mm / m ² · day · atm.
(23 ° C., 100% RH) Deoxidizing resin layer formed by granularly dispersing a deoxidizing agent composition that causes a deoxidizing reaction by supplying water to a resin having a deoxidizing resin layer and an oxygen permeability of 100 cc / m ²
・ Day ・ atm (23 ℃, 100% RH)
To provide a packing for a lid having an oxygen absorbing function for sealing a container mouth formed by adhering an aluminum foil surface of an aluminum foil laminated sheet formed by laminating aluminum layers in this order through a temporary adhesive material Is. Further, according to the present invention, in the above-mentioned packing for a lid, the packing for a lid having an oxygen absorption function according to claim 1, wherein an oxide of an alkaline earth metal is dispersed in a granular form in the deoxidizing resin layer. Is provided.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, the sheet-like packing material as a packing base material is usually a cap of a container,
Any packing material used by being attached to the back surface of the lid or the like can be used. Examples of the base material that constitutes the sheet-like packing material include paperboard (including surface-treated products), synthetic paper, non-woven fabric, silicone rubber, urethane rubber,
Rubber materials such as soft polyethylene, expanded polyethylene, expanded polypropylene, expanded polystyrene,
Examples of plastic materials include foamed polyurethane and foamed vinyl chloride resin. Of these, foamed plastic materials are preferable, and foamed polyethylene and foamed polypropylene are most preferable, in consideration of water resistance, dust generation, and processability with other materials to be laminated.

As the temporary adhesive, polypropylene, polyethylene, EVA, ionomer, EAA, E
MMA, EEA, wax, etc. can be used. This temporary adhesive material is for temporarily bonding the aluminum foil laminated sheet and the base material, and the sheet-like packing material is loaded on the inner bottom surface of the cap of the glass container so that the base material side is the inner side. When the cap is removed from the container after the cap is fitted into the container, it has a function of peeling the base material and the aluminum foil from the temporary adhesion site.

As the aluminum foil constituting the aluminum foil laminated sheet, a general soft aluminum foil or the like can be used, and the aluminum foil surface can be subjected to necessary printing or the like. The thickness of the aluminum foil to be used is not particularly limited, but is preferably 5 to 20 μm, most preferably 5 to 10 μm in view of workability and the like.

The second layer laminated on the aluminum foil has an oxygen permeation coefficient corresponding to the oxygen absorption layer of 200 cc · 0.1 mm / m ² · day.
A deoxidizing resin layer obtained by granularly dispersing a deoxidizing agent composition that causes a deoxidizing reaction by receiving water supply to a resin having atm (23 ° C., 100% RH) or more. As the oxygen scavenger composition to be dispersed in the second layer, a granular material is selected as a reducing substance to be a main agent for the oxygen scavenging reaction, and the oxygen scavenger composition other than the main agent such as a catalyst or an auxiliary agent is formed on the surface of the granular main agent. A product obtained by coating the product, or a product obtained by mixing all the oxygen scavenger compositions such as the reducing agent as the main ingredient and granulating the composition is preferably used.

The oxygen scavenger composition to be added to the second layer includes metal powder such as iron powder and aluminum powder, inorganic salts such as ferrous salt and dithionite trisalt, ascorbic acid and salts thereof. Also preferred are those containing a reducing substance such as catechol and glycerin as a main ingredient. This main ingredient is used as a deoxidizer composition in the form of granules together with other components.
Among these, in particular, metal powder to which a metal halide is attached on the surface by the method disclosed in Japanese Patent No. 1088514, metal powder and metal halide, and if necessary, other additives such as a binder. Those granulated by using are preferably used.

Iron powder is preferable as the metal powder, and the metal iron is not particularly limited in purity as long as it can carry out the above-mentioned deoxidation reaction and can be dispersed in a thermoplastic resin, and partly. May be already oxidized or may be an alloy with another metal. As a suitable example, iron powder represented by reduced iron powder, atomized iron powder, electrolytic iron powder and the like is preferable. Further, in the case of particulate metallic iron, when it is dispersed in a thermoplastic resin to form a layer, the film thickness is made thin and the surface is made smooth, so that the particle size is smaller. Is good. Specifically, the average particle size is preferably 200 μm or less, and particularly preferably 50 μm or less.

The metal halide acts catalytically on the oxygen absorption reaction of metallic iron in the thermoplastic resin. Examples of the metal include alkali metals, alkaline earth metals, copper, zinc, aluminum, tin and iron. , At least one selected from the group consisting of cobalt, and nickel. Particularly, lithium, potassium, sodium, magnesium, calcium, barium and iron are preferable. Further, examples of the halide include chloride, bromide, and iodide, and chloride is particularly preferable. The amount of metal halide is preferably 0.1 to 20 parts by weight per 100 parts by weight of metallic iron. Substantially all of the metal halide adheres to the metallic iron, and there is almost no metal halide liberated in the thermoplastic resin, and when the metal halide acts effectively, 0.1-5 wt. The department is enough.

The metal halide is preferably added by a method that does not easily separate from metallic iron in the thermoplastic resin. For example, a method of pulverizing and mixing using a ball mill, a speed mill or the like to attach the metal halide fine particles to the metal iron surface, or a method of mixing and drying an aqueous metal halide solution and metal iron to form a halogen on the metal iron surface. A method of attaching fine metal oxide particles is particularly preferable. In order to confirm that the metallic iron and the metal halide are not separated in the thermoplastic resin, the constituent elements of the iron and the metal halide are both contained in the metallic iron particles captured by an electron beam microanalyzer. Then the purpose has been achieved.

The particle size of the particulate oxygen scavenger composition dispersed in the resin forming the second layer has an average particle size of 2 to 200 μm.
Is preferable, and more preferably 5 to 50 μm. In the present invention, it is possible to obtain a practically sufficient oxygen absorption rate by dispersing the particulate oxygen scavenger composition containing the necessary components for the oxygen absorption reaction in the resin.

Further, it is preferable to disperse the alkaline earth metal oxide together with the oxygen scavenger composition in the resin forming the second layer. Examples of the alkaline earth metal oxide include magnesium oxide, calcium oxide, strontium oxide, and barium oxide. Magnesium oxide and calcium oxide are particularly preferable in terms of availability and reactivity. These are also preferably used in the form of fine particles, and have an average particle size of 2 to 2
00 μm is preferred. In order to reduce the thickness of the oxygen absorbing resin layer of the second layer, it is preferable that the particle size of metallic iron be equal to or smaller than that.

In the present invention, the alkaline earth metal oxide is dispersed in the resin at the same time to prevent the foaming phenomenon due to the water content of the oxygen scavenger composition at the time of forming the layer and improve the workability. At the same time, the effects of improving the storage stability of the final product, suppressing hydrogen generation, suppressing odor, etc. can be obtained.
In particular, when a method of adhering a metal halide to iron powder is adopted as the oxygen absorber composition, the moisture contained in the granular oxygen absorber composition is generally used in the master-batch drying method. It is difficult to reduce the amount of bubbles, and it is effective as a means for preventing the foaming phenomenon during film formation processing. In particular, when the metal halide is calcium chloride or the like, it has been found that releasing the crystallization water at high temperature in the film forming step is an unavoidably effective means because it contains the crystallization water.

As the thermoplastic resin constituting the second layer, various polyethylenes, polypropylenes, polybutenes, polymethylpentenes, polymethylmethacrylates, various ethylene copolymers, polyvinyl chlorides, polyamides, polycarbonates, polyesters and modifications thereof The resins can be used alone or as a mixture. Among them, polyethylene, polypropylene, polybutene, polymethylpentene, various ethylene copolymers and modified products thereof are preferable as those having excellent oxygen permeability.

The compounding ratio of the oxygen scavenger composition in the second layer is preferably 10 to 80% by weight, and 20 to 7 is preferable.
It is more preferably 0% by weight. If the blending ratio is too low, the oxygen absorption performance is lowered, and if it is too high, the workability is lowered. If the content of the alkali metal oxide is too low, sufficient foaming preventing effect and storage stability improving effect cannot be obtained, and if it is too high, the oxygen absorbing performance will be affected during use. 0.1-5 wt% in the composition
% Is preferred. The thickness of the second layer is determined in consideration of the setting of oxygen absorption capacity, packing property, workability, etc.
˜150 μm, preferably 20 to 100 μm.

The oxygen scavenger composition and the alkaline earth metal oxide can be mixed with the thermoplastic resin by mixing and kneading with a stirring blade mixer, a twin-screw extruder or the like.
Other methods are also acceptable. Further, the oxygen scavenger composition and the alkaline earth metal oxide are respectively dispersed in the thermoplastic resin at a high concentration in advance, and both are kneaded and extruded together with an additional thermoplastic resin if necessary in a single-screw extruder or the like. It is also possible to adopt a masterbatch system. In the second layer, in addition to the oxygen scavenger composition and the alkaline earth metal oxide, a colorant such as an organic dye, an inorganic dye or a pigment, a silane-based or titanate-based dispersant, if necessary, It is also possible to add a water absorbing agent such as a polyacrylic acid compound, a filler such as clay, mica, silica and starch, a gas absorbing agent such as zeolite and activated carbon.

Further, the seal layer laminated with the second layer has an oxygen permeability of 100 cc / m ^{2 in} order to obtain a large oxygen absorption rate.
・ Day ・ atm (23 ℃, 100% RH) or more is required. Further, more preferably, the oxygen permeability thereof is 200 cc / m ² · day · atm (23 ° C, 100% R
H) or higher is desired. This seal layer is selected in consideration of the adhesiveness with the container mouth, the packing property, and the like. Further, in the case of adhering to the mouth portion of the glass bottle, it is also effective to perform pretreatment such as hot coating in advance on the mouth portion of the glass bottle in order to improve the adhesiveness.

Examples of the seal layer material include various hot melts, various polyethylenes, polypropylenes, polybutenes, polymethylpentenes, polymethylmethacrylates, various ethylene copolymers, and modified resins thereof alone or as a mixture. Can be used. Among them, various ethylene copolymers including polyethylene, polypropylene, polybutene, polymethylpentene, and silicon, and modified products thereof are preferably used as those having excellent oxygen permeability. The thickness and the like are selected in consideration of oxygen permeability, required seal strength, and adhesiveness with container material,
70 μm, more preferably 10 to 50 μm is desirable. Furthermore, in order to conceal the color resulting from the oxygen scavenger composition of the second layer, it is preferable to add a colorant such as an organic dye, an inorganic dye or a pigment to the seal layer, if necessary.

As a method for producing an aluminum foil laminated sheet,
Various methods can be adopted, for example, a method of forming a deoxidizing layer and a seal layer on one surface of an aluminum foil by sequentially extrusion laminating. In addition, it is also possible to adopt a method of laminating a film formed by coextruding a deoxidizing layer and a seal layer while forming an aluminum foil and an adhesive layer such as dry laminate or polyethylene by extruding laminate. In either method, a known method can be applied to the formation of the laminated sheet, and various means used in conventional resin processing can be applied.

As a method for manufacturing the lid packing of the present invention, after the above-mentioned aluminum foil laminated sheet is prepared, the base material and the other surface of the aluminum foil are temporarily adhered through a temporary adhesive material to form a sheet. It can be manufactured by preparing a packing and punching it into a desired size. The thickness of the lid packing is selected from the oxygen absorption capacity setting, workability, packing property and the like, and is used in the range of 0.2 to 5 mm. A thickness of 0.5 to 3.0 mm is preferable from the viewpoint of loadability and workability. If it is too thin, the packing property will be poor, and if it is too thick, there will be problems in workability and loadability.

[0027]

EXAMPLES Next, more detailed description will be given with reference to examples.
Note that the present invention is not limited to this embodiment. Example 1 Iron powder having a diameter of 35 μm of 50% by weight was placed in a vacuum mixing dryer with a heating jacket, and dried by heating at 130 ° C. under a reduced pressure of 10 mmHg, while 100 parts by weight of the iron powder was calcium chloride: sodium chloride = A mixed aqueous solution mixed at a ratio of 0.5: 0.5: 2.5 (parts by weight) was sprayed to obtain a granular oxygen scavenger composition in which calcium chloride and sodium chloride were adhered to the iron powder surface. . Next, polyethylene and the oxygen scavenger composition were mixed in a 45 mmΦ co-rotating twin-screw extruder,
Polyethylene: oxygen scavenger composition = 2: 3 by weight ratio, and after cooling with a net belt with a blower, it was passed through a pelletizer to obtain oxygen absorber composition-containing pellets.

Then, a two-layer two-layer co-pushing film unit consisting of the first and second extruders, a feed block, a T-die, a cooling roll and a film take-up machine was used, and a white pigment was used for the first extruder. The added polyethylene was extruded from the respective extruders using the oxygen absorber composition-containing pellets in a second extruder to obtain a two-layer film. Next, an aluminum foil having a thickness of 9 μm was prepared, and polyethylene was extruded and laminated between the deoxidizing layer side of the two-layer film and the aluminum foil to obtain an aluminum foil laminated sheet. Next, the packing base material made of expanded polyethylene of 0.9 mm and the aluminum foil surface of the aluminum foil laminated sheet were laminated and temporarily adhered by a laminate by extruding polypropylene of 30 μm as a temporary adhesive material. Next, a packing material having a circular shape of 60 mmΦ was punched out to obtain a packing having an oxygen absorbing function. This packing was loaded on the back surface of the glass bottle cap with the packing base material side facing inward to obtain a cap having an oxygen absorbing function.

A glass bottle having a capacity of 100 cc was filled with orange juice of natural fruit juice in an amount such that the head space was 10 cc, fitted with the cap, and electromagnetic waves were applied from the outer top surface of the cap by an electromagnetic induction heating device. Then, the aluminum foil was heated to soften the seal layer and adhesively sealed with the mouth of the glass bottle. The glass bottle containing the orange juice was stored under irradiation of a fluorescent lamp (brightness 2000 lux) at 35 ° C., and the gas composition in the bottle was analyzed by gas chromatography every day, and the orange juice was discolored. The state of change of the scent was tested by observing the situation and conducting sensory tests. The result is
The results are shown in Table 1.

Example 2 Calcium oxide and polyethylene having an average particle size of 20 μm were kneaded at a weight ratio of 50/50 with the same 45 mmΦ co-rotating twin-screw extruder as in Example 1 to obtain calcium oxide-containing pellets. The oxygen scavenger composition-containing pellets obtained in Example 1 and the calcium oxide-containing pellets were dry-blended in a ratio such that the calcium oxide content was 2% by weight. Seal layer 2
A layer film was made. Then, the aluminum foil laminated sheet was used in the same manner as in Example 1 to have an oxygen absorbing function.
A 0 mmΦ packing was prepared and subjected to the same test. The results are shown in Table 1 together with the results of Example 1.

Comparative Example 1 A circular packing having a diameter of 60 mm was prepared using only the same packing base material as in Example 1 and the same experiment as in Example 1 was conducted. The results are combined with the results of Example 1 and Example 2. , Shown in Table 1.

Comparative Example 2 100 parts by weight of iron powder having a particle diameter of 35 μm at 50 wt% and 1 part by weight of a calcium chloride / sodium chloride = 1/1 mixture were mixed in a Henschel mixer to obtain an oxygen scavenger composition. In the same manner as in Example 1 except that this was used in place of the granular oxygen scavenger composition, an oxygen scavenger-blended pellet was prepared, a two-layer film, an aluminum foil laminated sheet, and then oxygen. A 60 mmΦ packing having an absorbing function was prepared and subjected to the same test. The results are shown in Table 1 together with the results of Example 1, Example 2 and Comparative Example 1.

[0033]

[Table 1]

[0034]

The packing having an oxygen absorbing function of the present invention is excellent in packing property, liquid resistance and safety and hygiene due to being composed of a specific material and a unique structure.
In addition, it has a high oxygen absorption performance and has an excellent oxygen-sealing function that can cope with long-term storage due to its excellent sealing property, and exerts a quality retention effect. Further, the form thereof is also compact and thin, excellent in loadability to the lid, and also excellent in processability at the time of production, which facilitates its commercial production. Furthermore, in the present invention, by using a deoxidizing layer in which a granular oxygen scavenger composition is dispersed, a practical oxygen absorption rate is obtained, and contamination by powder or the like in the manufacturing and processing stage is eliminated, and electromagnetic induction heating is performed. Sealing and bonding can be performed without any trouble even when the device is heated, and the seal layer structure prevents elution of oxygen scavenger components such as rust, and the lid packing is extremely excellent in safety and hygiene. As is apparent from the above, according to the present invention, including juice, liquor, wine, other liquid beverages, salted fish, tsukudani, jam, marmalade, salmon flakes, and other high-moisture foods. Used to seal various foods, or storage containers that contain medicines, etc. It exerts its excellent effect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a lid packing.

FIG. 2 is a cross-sectional view of a container sealed using a lid packing.

[Explanation of symbols]

 1 Packing for lid 2 Packing base material 3 Temporary adhesive material 4 Aluminum foil 5 Deoxidizing layer 6 Seal layer 7 Cap 8 Container 9 Contents

Claims (2)

[Claims] 1. A substrate having an aluminum foil and an oxygen permeability coefficient of 20.
0cc ・ 0.1 mm / m ²・ day ・ atm (23 ℃, 100% R
H) The oxygen absorbing resin layer formed by granularly dispersing a deoxidizing agent composition that causes a deoxidizing reaction by receiving water supply to the resin having the above H) and an oxygen permeability of 100 cc / m ² · day · atm (23
C., 100% RH) or higher) Oxygen for sealing the container mouth formed by adhering the aluminum foil surface of the aluminum foil laminated sheet formed by laminating the seal layers in this order through a temporary adhesive. Packing for the lid that has an absorption function. 2. The deoxidizing resin layer is formed by granularly dispersing an oxide of an alkaline earth metal together with the deoxidizing composition.
A packing for a lid having the described oxygen absorbing function.