JPH06227557A - Bottle lid having oxygen absorbing property - Google Patents

Abstract

PURPOSE:To rapidly absorb oxygen in a head space of a product which is likely to be oxidized sealed in a container so as to prevent oxidization of the product by providing a porous liner material having oxygen absorbing ability on an inner face of the bottle lid. CONSTITUTION:A bottle lid 1 has a liner part at a bottom of a lid body 2, while the liner part has a packing 3 and has a thick expanded part 4 being an oxygen absorbing part at the center. Resin used as the packing 3 and the porous expanded part 4 may include low density polyethylene(LDPE), polyolefin such as polypropylene, ethylene-vinyl acetate 8 copolymer(EVA), polyester or polyvinyl chloride(PVC). The liner material contains at least one kind of oxygen absorbing agent selected from polyolefin, large-ring polyamine, ascorbic acid and ascorbic acid salt.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a lid with a liner material such as a screw cap of a container or a lid of a bottle,
The present invention relates to a bottle lid having an oxygen absorption capacity. More specifically, the present invention relates to a bottle lid used for a glass bottle, a PET container, or the like for filling and sealing a product such as a fruit juice beverage which is easily oxidized. INDUSTRIAL APPLICABILITY The bottle lid of the present invention eliminates oxygen in the head space inside the packaging container and dissolved oxygen in the article to maintain the quality of the article and preserve it for a long time.

[0002]

2. Description of the Related Art In beverages such as juice and beer, or products such as seasonings and pharmaceuticals, the active ingredient is denatured due to the presence of oxygen, and the quality such as flavor and color tone is changed to lower the commercial value. Products that easily oxidize are filled in oxygen-barrier containers such as bottles and cans, and in order to prevent oxidation due to residual oxygen in the container, vacuum packaging or closed packaging with free space gas replacement is required. Has been done. However, such a sealing method requires a high-pressure inert gas supply device and has a low production efficiency. Moreover, with such a method, the oxygen concentration in the packaging container can only be reduced to about 1 to 2%, and the aroma and volatile components of the food are often lost when oxygen is removed.

For this reason, it has been proposed to prevent oxidation by using a chemical antioxidant. This method uses butylhydroxytoluene, butylhydroxyanisole,
An antioxidant such as ascorbic acid is added to a food, and oxygen is reacted with the antioxidant before the oxygen reacts with the food to prevent the food from being oxidized. However, when such an antioxidant is added to beer or wine, it often causes off-flavor (smell, smell). Further, these antioxidants need to be described on the label as food additives, and in recent years, there is a tendency that general consumers who are targeting additive-free foods do not like them. There is also a method of enclosing a package of an oxygen absorbent, but these components are eluted and are not suitable for liquid products. Further, it has been proposed to incorporate an oxygen absorbing substance into the packaging material. However, since any of the oxygen absorbing substances used here is easily decomposed by heat, it is necessary to use a resin having a low melting point such as polyethylene, EVA, or polyvinyl chloride as a material for the packaging material. Further, when the oxygen absorbing film on which such an oxygen absorbing substance is fixed is immersed in water for a long time, the oxygen absorbing substance is eluted into the contents.

[0004]

Therefore, a resin containing an oxygen absorbent is used in the upper part of a container such as a beer crown liner for the purpose of absorbing oxygen in the head space which rarely comes into direct contact with the contents. There is also. For example, JP-A-53-69786 and JP-A-1-199879 disclose a container and a bottle lid in which a liner material having an oxygen absorbing ability is attached to the inner surface of the container member such as a bottle lid. However, it is difficult for such a bottle lid to quickly absorb the dissolved oxygen in the liquid, and it cannot be said that the bottle lid still has sufficient antioxidant ability. That is, in such a method, rather than the absorption speed of oxygen by the oxygen absorbent,
The contents oxidize quickly. In particular, it is difficult to prevent oxidation of easily oxidizable products such as orange juice and beer.

It is an object of the present invention to rapidly absorb the oxygen in the headspace of an oxidizable product that is sealed in a container,
It is intended to provide a bottle lid capable of preventing the oxidation of a product.

[0006]

As a result of various studies to solve the above problems, the present inventors have found that the liner material inside the bottle lid is provided with a porous expansion portion having an oxygen absorbing capacity. The present invention has been completed based on the knowledge that the intended purpose can be achieved.

The present invention provides a bottle lid having an inner surface of the bottle lid provided with a liner material having a porous expanded portion having an oxygen absorbing ability. INDUSTRIAL APPLICABILITY The bottle lid of the present invention can quickly reduce oxygen in the head space inside the packaging container, prevent oxidation of products such as food and drink, and maintain quality.

FIG. 1 is a sectional view showing a specific example of the bottle lid of the present invention. The bottle lid 1 of the present invention has a liner portion on the bottom of the lid body 2. The liner portion has a packing portion 3 similar to the conventional one, and has a thick expanded portion 4 which is an oxygen absorbing portion in the center thereof. The resin used for the liner material having the packing part and the porous expanded part is a polyolefin such as low density polyethylene (LDPE) or polypropylene, or an ethylene-vinyl acetate copolymer.
(EVA), polyester, polyvinyl chloride (PVC) and the like are preferable.

Examples of the oxygen absorbent include ascorbic acid, ascorbate and porphyrin complexes, macrocyclic polyamine complexes such as polyaminocarboxylic acid, and the like. As ascorbate, sodium salt,
Examples thereof include potassium salt and calcium salt. Further, as porphyrins, Fe, Mg, Z as central metals
Examples thereof include metal chelate compounds of porphyrins such as protoporphyrin having n, Co, Ni, Cu and the like, tetraphenylporphyrin, alkyl esters thereof, and imidazole coordination compounds thereof.
Further, examples of the macrocyclic polyamine complex include cyclam complexes such as Fe, Mg, Zn, Co, Ni and Cu as central metals.

The blending amount of these oxygen absorbents with respect to the base resin varies depending on the kind of the oxygen absorbing agent and its oxygen absorbing ability, but generally 0.01 to 20 parts by weight is blended with 100 parts by weight of the base resin. preferable. If the blending amount is less than 0.01 parts by weight, the oxygen absorbing effect is not sufficient, and even if it exceeds 20 parts by weight, the effect does not change,
This is not preferable because the strength of the liner material decreases.

As the foaming agent, known foaming agents such as p, p'-oxybisbenzenesulfonylhydrazide (OBSH) and p-toluenesulfonylacetonehydrazone are preferably used. The blending amount of these foaming agents with respect to the base resin is preferably 0.5 to 5 parts by weight with respect to 100 parts by weight of the base resin.

In the liner material, the expansion rate of the porous expanded portion is preferably about 1 to 4 times.

The packaging container sealed by the bottle lid of the present invention must be oxygen barrier. As such a container, for example, a bottle, a can, a plastic molded container, a bag-shaped container or the like is used. Polyvinylidene chloride, saponified ethylene-vinyl acetate copolymer, polyester, polyamide, polypropylene and the like are used alone or in combination as a material for forming the plastic molded container. As the composite material, a laminate of plastic and aluminum foil, rubber or other different materials may be used. The bottle lid of the present invention is a bottle lid for storing fruit juice drinks, carbonated drinks, coffee, teas, alcoholic drinks, seasonings, other foodstuffs, pharmaceuticals, or various liquids, viscous substances and other easily oxidizable products. Is particularly suitable as

In order to fill the product using the bottle lid of the present invention, the contents whose quality is liable to be significantly changed or deteriorated by oxidation are simply filled in the container, and the bottle lid is attached to the opening. Oxygen existing in the head space above the container is removed by the oxygen absorbent in the expanded portion of the liner material. A known filling and packaging machine may be used for filling the contents.

In order to manufacture the lid of the present invention by injection molding, for example, as shown in FIG. 2, the lower mold 6 whose temperature is adjusted in advance is used.
The degreased lid main body 2 (metal bottle lid or screw cap) is preheated and inserted. After the insertion, the upper mold 7 is lowered to clamp the mold, and the resin containing the foaming agent and the oxygen absorbent is injected from the injection molding nozzle 8. The injected resin forms a packing part 3 and an expanding part (oxygen absorbing part) 4 while foaming in the mold. An undercut 5 is preferably formed on the inner periphery of the inner surface of the lid body 2 to prevent the liner material from falling off. Further, the undercut also facilitates the alignment of the mold. It is preferable that the injected resin strongly adheres to the lid body 2 due to the undercut shape of the lid body 2 and heat fusion. If necessary, an adhesive such as hot melt may be applied to the inner surface of the lid in advance.

Further, since the injection molding nozzle 8 is highly likely to be fused with the foamed resin, the surface of the injection molding nozzle 8 may be coated with Teflon having a low friction coefficient. The bottom of the lid main body 2 needs to be sufficiently deoxidized and degreased in order to improve the heat fusion strength with the liner material. In particular, in order to increase the foaming rate of the oxygen absorbing portion, it is preferable to use a valve gate that can increase the gate diameter. By using a valve gate, the filling mark after molding becomes beautiful.

The lid thus obtained has a thick-walled inflated portion at the center as an oxygen absorbing portion as shown in FIG.

Since the base resin has an oxygen absorption capacity,
The packing part and the expanding part having an oxygen absorbing capacity can be integrally formed, and the central part of the liner material becomes the oxygen absorbing part.

The foamed resin functions as a cushion in the packing portion 3 and ensures the sealing property of the cap. In addition, the expanded portion 4 has a larger surface area and can absorb oxygen in a short time. Since polyethylene has a high oxygen permeability, even if there are many air bubbles in a sealed state, oxygen permeates inside and has a high oxygen absorption capacity.

[0020]

The bottle lid of the present invention has a porous oxygen absorption portion, has a high oxygen absorption rate, and rapidly reduces the oxygen concentration in the head space in the container.

[0021]

EXAMPLES Next, the present invention will be described in more detail based on examples.

Example 1 LDPE (melting point 109 ° C., MI 0.51 g / 10 minutes; 190 ° C .; 2.16 kg load) 92 parts by weight oxygen absorber sodium ascorbate 5 parts by weight Blowing agent (Sankyo Kasei Co., Ltd. ), Cellumic M65 and MB203B) 3 parts by weight Using the raw material having the above composition, injection molding was performed at an injection temperature of 150 ° C., and a foamed porous expansion part and a packing part were formed inside the bottle lid as shown in FIG. It was molded integrally. The expansion ratio of the obtained expanded part was 2.2 times. As shown in Table 1 below, bottle caps having excellent oxygen absorption capacity were obtained.

[Example 2] EVA (M
I: 1.53 g / 10 minutes; 190 ° C .; 2.16 kg) was used, and injection molding was performed under the same raw material composition and conditions as in Example 1 (foaming ratio: 2.5 times). As shown in Table 1 below, a bottle cap having an excellent oxygen absorption capacity similar to that of Example 1 was obtained.

Comparative Example 1 Injection molding was carried out under the same raw material composition and conditions as in Example 1 except that no foaming agent was added. The results are shown in Table 1 below.

(Measuring Method of Oxygen Absorption Capacity) The oxygen absorption capacity of each of the obtained three types of bottle caps was measured. Distilled water (170 mL) was put into a glass bottle (200 mL), and the oxygen concentration in the upper headspace (30 mL) was measured with time (initial oxygen amount was 20.9%). As shown in Table 1 below, the bottle lid of the present invention having a foamed oxygen absorbing portion has a high oxygen absorbing speed.

Table 1 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 1 day (%) 3 days (%) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Example 1 (LDPE) 17.5 11.2 〃 2 ( EVA) 18.2 12.0 ──────────────────────────────────── Comparative Example 1 (LDPE) 20.2 18.7 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

[0027]

When the bottle lid of the present invention is used, the oxygen concentration in the head space in the container is rapidly lowered, so that the oxygen concentration in the product is also rapidly lowered. For this reason, it is possible to prevent the quality and change of the quality of the packaged article from being maintained for a long period of time, maintain the flavor and color tone of the food and drink, and prevent the change of the active ingredient.

[Brief description of drawings]

FIG. 1 is a sectional view showing a specific example of a bottle lid of the present invention.

FIG. 2 is a schematic cross-sectional view showing a method for manufacturing a bottle lid of the present invention.

[Explanation of symbols]

 1 Bottle Lid 2 Lid Main Body 3 Packing Part 4 Expanding Part 5 Undercut 6 Lower Mold 7 Upper Mold 8 Injection Molding Nozzle

Claims (3)

[Claims] 1. A bottle lid having an inner surface of the bottle lid provided with a liner material having a porous expanded portion having an oxygen absorbing ability. 2. The bottle lid according to claim 1, wherein the liner material is based on at least one resin selected from polyolefin, ethylene-vinyl acetate copolymer, polyester and polyvinyl chloride. 3. The bottle cap according to claim 1, wherein the liner material contains at least one oxygen absorbent selected from porphyrins, macrocyclic polyamines, ascorbic acid and ascorbate.