JPH10235189A - Oxygen absorbent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oxygen absorbent for improving the oxygen absorption speed and eliminating the oozing of a chemical from a packaging material by using the oxygen absorbent constituted of a main agent composed of gallic acid as a main component and a pH adjustor composed of sodium carbonate decahydrate as a main component. SOLUTION: An oxygen absorbent is constituted of a main agent composed of gallic acid as a main component and a pH adjustor composed of sodium carbonate decahydrate as a main component. The main agent is composed of gallic acid as a main component, and if required, another reducing substance can be added to the main agent. As for the reducing substance, for example, a compound containing an enediol can be used, and preferably ascorbic acids or low-molecular phenols are used. The pH adjustor is composed of a basic substance composed of sodium carbonate decahydrate as a main component, and other component such as hydroxide, carbonate, bicarbonate or phosphate of an alkali metal or alkaline earth metal can be contained therein. Either hydrous salt or anhydrous salt can be used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an oxygen absorbent,
The present invention relates to an oxygen absorber suitable for packaging foods, alcohol, beverages such as juices, and the like.

[0002]

2. Description of the Related Art Conventionally, the presence of oxygen in a package in which food or the like is wrapped has caused the content of the food or the like to be oxidized and deteriorated or discolored. In addition, if insects and microorganisms are present in the package, the microorganisms and the like grow and propagate, causing contamination and decay. In order to solve such a problem, oxygen in the package is removed.

[0003] There are several methods for removing oxygen, and one is vacuum packaging in which the interior of the package is evacuated during packaging. This vacuum packaging is effective for a liquid material or the like that does not need to maintain its shape. However, vacuum packaging does not remove so-called dissolved oxygen already dissolved in the liquid material. Another way is
This is a method in which the air in the space in the package is replaced with a gas containing no oxygen; for example, nitrogen gas. Since this method can make the pressure inside the package equal to the outside air pressure, it is also effective for the packaging of articles that need to maintain its shape. However, in this gas replacement method, the oxygen removal rate is not sufficient, and oxygen remains in the space. Then, as in the above, dissolved oxygen in the liquid is not removed.

[0004] As yet another alternative, oxygen absorbers are widely used. As the oxygen absorbent, those having iron powder as a main component and those having ascorbic acid or a salt thereof as a main component have been put to practical use. Iron powder is mainly used for oxygen absorption by the oxidation reaction of iron. Ascorbic acid-based oxygen absorbers are based on the principle of oxygen absorption based on the consumption of oxygen accompanying the decomposition reaction of ascorbic acid (salt). Have been. As described above, the oxygen absorbent absorbs (consumes) oxygen through the reaction, so that it can not only absorb oxygen in the space almost completely but also absorb dissolved oxygen dissolved in the liquid material. There is.

[0005] As the form of the oxygen absorbent, the respective components are mixed in a powder state or granulated into granules.
It is common to package it in a breathable packaging material.
As another form, there has been proposed a method of dissolving each component in a solvent such as water to form a solution, and impregnating the solution with filter paper or the like for use. There are also proposals in which the above components are mixed (kneaded) with a resin, and a packaging container is manufactured using the resin, or the resin is used as a part of the container, for example, a liner of a cap.

However, since the iron-based oxygen absorber uses iron powder, the iron-based oxygen absorber is caught by a metal detector for foreign substance inspection, and there is a problem that it cannot be put into the package before the foreign substance inspection. .

On the other hand, ascorbic acid-based oxygen absorbers
Ascorbic acid (salt), iron sulfate, carbonate, and the like are used as components, and fillers are mixed with the components and granulated to form granules. Since this oxygen absorbent does not use metal powder, there is no problem in using the metal detector and the microwave oven, and there is an advantage that hygiene and safety are higher than metal powder.

[0008]

However, ascorbic acid-based oxygen absorbents have a problem that the oxygen absorption rate is lower than that of iron-based oxygen absorbents. If the oxygen absorption rate is low, the contents may be oxidized or decomposed by oxygen before the oxygen absorbent absorbs oxygen if the contents are very sensitive to oxygen. There is.

[0009] In order to improve the oxygen absorption rate of the ascorbic acid-based oxygen absorbent, as described above, the invention in which the components (ascorbic acid (salt) and iron sulfate) are used in the form of an aqueous solution (Japanese Patent Application Publication No. Hei 11 (1994)). -42745)),
Although an invention characterized by adding tocophenol or an organic acid (see Japanese Patent Publication No. 3-49315) has been proposed, a sufficient oxygen absorption rate has not yet been realized.

As described above, conventionally used or proposed oxygen absorbents have not been satisfactory in some applications in terms of safety and / or oxygen absorption rate.

In order to solve the above-mentioned problems, the present inventor has proposed an oxygen absorber comprising a main ingredient mainly composed of gallic acid and a pH adjuster mainly composed of sodium carbonate.
The inventors of the present invention invented a device which satisfies the oxygen absorption rate by reducing the particle diameter of sodium carbonate to 50 μm or less (Japanese Patent Application No. 8-1)
No. 25600).

The present invention further improves the oxygen absorption rate as compared with the oxygen absorber described in Japanese Patent Application No. 8-125600,
An object of the present invention is to provide an oxygen absorbent that does not cause stains from a packaging material of a medicine.

[0013]

Means for Solving the Problems A first invention of the present invention is:
An oxygen absorber comprising a main ingredient mainly composed of gallic acid and a pH adjuster mainly composed of sodium carbonate decahydrate.

Further, a second invention of the present invention is an oxygen absorbent characterized by adding calcium hydroxide to the first invention.

[0015] A third invention of the present invention is an oxygen absorbent characterized in that an additive for improving reactivity is added to the first invention or the second invention.

A fourth aspect of the present invention is an oxygen absorbent characterized by adding crystalline cellulose to the first to third aspects to form granules.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to embodiments. The oxygen absorbent according to the present invention comprises a main ingredient mainly composed of gallic acid and a pH adjuster mainly composed of sodium carbonate decahydrate.

Gallic acid is a substance that has long been recognized as an antioxidant and has been added to foods, and is a substance whose safety has been sufficiently confirmed. In the present invention, gallic acid is mainly used as the main ingredient. Ingredients. Other reducing substances can be added to the main agent as needed. Examples of the reducing substance include a compound having an enediol group,
Preferred are ascorbic acids or low molecular weight phenols.

Examples of the ascorbic acids include water-soluble salts such as L-ascorbic acid, D-isoascorbic acid, sodium salts and calcium salts thereof, and derivatives thereof (for example, 6-O-α-glycopyranosyl-L). -At least one of the 2- or 3-positions is a hydroxyl group and is water-soluble, such as ascorbic acid).

The low-molecular-weight phenols include:
Catechol, pyrogallol, salts or derivatives thereof.

The pH adjuster is composed of a basic substance containing sodium carbonate decahydrate as a main component, and hydroxides, carbonates, hydrogencarbonates, phosphorus salts of alkali metals or alkaline earth metals as other components. Acid salts can be included. These may be hydrated salts or anhydrous salts. More specifically,
Lithium hydroxide, sodium hydroxide, potassium hydroxide,
Rubidium hydroxide, beryllium hydroxide, magnesium hydroxide, strontium hydroxide, barium hydroxide, lithium carbonate, magnesium carbonate, potassium carbonate, lithium hydrogen carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, sodium potassium carbonate, potassium magnesium carbonate, phosphorus And potassium hydrogen phosphate and the like.

Calcium hydroxide has the function of absorbing carbon dioxide gas generated by decomposition of gallic acid and sodium carbonate when a drug is blended in a blender. When the addition ratio of calcium hydroxide is 5% or less, the gas generated during mixing cannot be absorbed, and the pressure inside the blender may become high. Further, since it is a poorly soluble drug, it has a function of suppressing the reacted drug from becoming liquid. Further, it is an alkaline substance and also plays a role of pH adjustment, and has a function of increasing the rate of dissociating the hydroxyl group of gallic acid.

The additives for improving the reactivity include activated carbon, activated clay, zeolite and the like. By adding these, the chance of contact of the main agent with oxygen can be increased, and the absorption rate can be improved. The pH adjuster is used after being pulverized by a known pulverizing means so as to have a fine powder, preferably an average particle diameter of 50 μm or less.

It is preferable that granules are formed by adding crystalline cellulose such as Avicel and hydroxypropylcellulose and granulating them. In this way, prevention of stains and
The suitability for handling and filling can be improved.

The above-described oxygen absorbent can be used in the form of a powder in the form of a gas-permeable packaging material, similarly to the conventional oxygen absorbent.

The oxygen absorbent may be mixed and dispersed in a polyolefin resin such as polyethylene and melt-extruded to form a film or sheet.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below. <Examples 1 to 12> 1 kg each of gallic acid, sodium carbonate decahydrate, calcium hydroxide and activated carbon was mixed for 15 minutes in a 4 l capacity rocking mixer (Aichi Electric) according to the mixing ratio (% by weight) shown in Table 1. Mix. As a method for evaluating the oxygen absorption capacity, 0.9 g of each of the mixed chemicals was filled in a sample tube as shown in FIG.
Place in a glass bottle adjusted to H, seal, store at 25 ° C., and measure the oxygen concentration in the headspace over time. Regarding the stain removal of the medicine, 0.9 g of each medicine is filled in a packaging material having a paper / PE / waffle / PE composition, stored in a mayonnaise bottle, and the stain removal from the packaging material is confirmed.

<Examples 13 and 14> 100 kg of gallic acid, sodium carbonate decahydrate, calcium hydroxide, activated carbon and Avicel were mixed in a blender having a capacity of 150 l for 15 minutes according to the mixing ratio (% by weight) shown in Table 1. After that, granulate with a granulator. In the same manner as in Examples 1 to 12, 0.9 g of the drug was evaluated.

<Comparative Example> A mixture of gallic acid and sodium carbonate (anhydrous), which are the oxygen absorbents having the highest oxygen absorption rate so far, in a ratio of 1: 1 (Japanese Patent Application No. 8-125600).
No. 2), the oxygen absorption capacity was evaluated by the same evaluation method as in the example. Table 1 shows the above results. For the evaluation of stain removal, the presence or absence of stain removal from the packaging material after storage for one week was observed.は indicates no stain, and X indicates stain.
The oxygen concentration was measured by Iijima Electronic Industries RO-102.

[0030]

[Table 1]

When the ratio of gallic acid is 25% by weight or more, the rate of oxygen absorption exceeds the conventional rate. The optimum weight ratio between gallic acid and sodium carbonate decahydrate is 1: 1. If the ratio of gallic acid to sodium carbonate decahydrate is 35% by weight or less, and if the ratio of calcium hydroxide is 5% by weight or more, no blemishes occur. At this time, in the sample without stains, the drug is hardly liquefied even after the oxygen absorption reaction. Conversely, the sample with spots had the drug liquefied. In addition, by adding Avicel to form granules, it was possible to prevent the occurrence of stains and to improve handling suitability and filling suitability.

From the above results, by setting the ratio of gallic acid to 25% by weight or more and 35% or less and the weight ratio of gallic acid to sodium carbonate decahydrate to 1: 1, oxygen in the conventional drug system was The absorption capacity could be exceeded. In addition, it has become possible to suppress the stain of the drug.

[0033]

The oxygen absorbent according to the present invention comprises a main ingredient mainly composed of gallic acid and a pH adjuster mainly composed of sodium carbonate decahydrate, thereby greatly increasing the oxygen absorption rate. can do. Further, by adding calcium hydroxide, it is possible to prevent the drug from being stained. Further, the addition of the additive for improving the reactivity can greatly increase the oxygen absorption rate. In addition, by adding crystalline cellulose to form granules, it was possible to prevent the occurrence of stains and to improve handling suitability and filling suitability.

[Brief description of the drawings]

FIG. 1 is a drawing showing an instrument for measuring oxygen absorption capacity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Mayonnaise bottle 2 ... Metal cap 3 ... Humidity adjusting liquid 4 ... Evaluation sample 5 ... Sample tube 6 ... Head space

Claims (4)

[Claims] 1. An oxygen absorber comprising a main ingredient mainly composed of gallic acid and a pH adjuster mainly composed of sodium carbonate decahydrate. 2. The oxygen absorbent according to claim 1, wherein calcium hydroxide is added. 3. The oxygen absorbent according to claim 1, wherein an additive for improving reactivity is added. 4. The oxygen absorbent according to claim 1, wherein crystalline cellulose is added to form a granule.