JPS6041983B2 - oxygen absorber - Google Patents

Description

[Detailed description of the invention] The present invention relates to an oxygen absorbent.

More specifically, the present invention relates to an oxygen absorbent containing ferrous acetate, sodium sulfate, and a filler. The oxygen absorbent according to the present invention is made to coexist in a sealed container with food or other materials that would rot, change in quality, or deteriorate due to contact or reaction with oxygen, and effectively absorb oxygen in the container. It has the effect of preventing spoilage, deterioration, and deterioration of foods, etc.

Conventionally, methods for preserving food products by preventing spoilage, deterioration, and deterioration include (1) refrigeration, (2) inert gas replacement using an inert gas such as carbon dioxide, ethylene, and nitrogen, and (3)
There are methods such as vacuum packing, where the storage system is vacuumed under reduced pressure.
Furthermore, there is also a method of adding food additives such as antioxidants and anti-corrosion agents to foods.

However, recently, the use of food additives to treat food dependence has come to be strictly restricted and regulated due to the adverse effects they have on animals, especially on the human body.
On the other hand, among the above preservation methods, the refrigeration method requires very large refrigeration equipment and complicated operations, and is also economically expensive. In addition, the inert gas substitution method and the vacuum packing method not only require complicated operations, but also have insufficient storage stability. Therefore, if a simple and inexpensive method for preserving food could be provided, its industrial value would be extremely large.

When preserving food, mold, bacteria, insects, and double bonds in the food are thought to be the causes of spoilage, deterioration, and deterioration, but most of these survive, reproduce, or undergo oxidation reactions in the presence of oxygen. This results in rot, deterioration, and deterioration. Therefore, when preserving food, if oxygen and J2 in airtight containers can be selectively removed, the survival and reproduction of mold, bacteria, insects, etc. can be prevented, and the oxidation reaction of double bonds in food can be prevented. It becomes possible to suppress this.

Conventional methods for preserving food by removing oxygen in packaging containers include (1) a method using hydrocasulfite as a main agent, calcium hydroxide or sodium bicarbonate, activated carbon, and water (Tokuko Sho); 47-19
(2) method using sulfite and activated carbon (see Japanese Patent Publication No. 51-12471). However, the former method has the disadvantage that a reaction occurs rapidly, making it difficult to handle and requiring water.In addition, the latter method inevitably generates sulfur dioxide gas. The present inventors have overcome the drawbacks of the previously proposed methods and selectively remove oxygen in the packaging of foods, medicines, equipment, etc., and remove mold, bacteria, and other substances from the contents of the packaging. The present invention was achieved as a result of research into an oxygen absorbent that prevents the survival and reproduction of insects, etc., and suppresses putrefaction, alteration, or deterioration caused by oxidation reactions, and can be applied to the safe and simple preservation of foods, etc. did.

According to the present invention, an oxygen absorbent containing ferrous acetate, sodium sulfate decahydrate, and a filler is provided.

The oxygen absorbent according to the present invention does not involve a rapid exothermic reaction, smoothly absorbs oxygen, and does not generate dangerous gases such as sulfur dioxide gas.

Furthermore, there is no need to add free water and it is extremely clean. Moreover, the oxygen absorbent of the present invention is almost white with a pale blue-green tinge, and it turns brown when it absorbs oxygen, so it is possible to observe whether oxygen absorption has taken place or not by observing the change in color. This fact can also be used to determine the freshness of the packaged contents. On the other hand, the oxygen absorbent of the present invention can also be used as a detection substance that detects the presence of oxygen in a certain atmosphere by utilizing the color change. The ferrous acetate in the oxygen absorbent of the present invention is an anhydrous salt, and is a white compound with a very slight bluish-green tinge that is solid at room temperature. If it is left in the air for a long time, it will emit a slight acetic acid odor, but in an oxygen atmosphere (for example, in the air) it can be used as an oxygen absorber that absorbs almost all oxygen. Can not. However, acetic acid No. 1
When iron is combined with sodium sulfate 10* salt and a filler, it has the ability to absorb oxygen, and the color changes from white with a pale blue-green tinge to brown due to the absorption of oxygen.

Moreover, in the oxygen absorbent of the present invention, no acetic acid odor is observed either before or after oxygen absorption, and the oxygen absorption rate can be changed by changing the proportions of the three components.

In particular, the use of a filler has the advantage of controlling the oxygen absorption rate, increasing the amount of oxygen absorbed, improving the dispersibility of ferrous acetate and sodium sulfate, and improving the air permeability of the oxygen absorbent. The ferrous acetate used in the present invention may be commercially available or may be synthesized by various methods.

For example, a method of reacting iron carbonyl with acetic acid [Zh.
Org. Khlm7 (1971) 11, 2316-1), a method of reacting reduced iron and acetic acid at room temperature under reduced pressure,
Further, ferrous acetate can be obtained by heating reduced iron with acetic acid under normal pressure or reduced pressure, but ferrous acetate obtained by other methods can be used in exactly the same manner.
On the other hand, the sodium sulfate salt used in the present invention is obtained, for example, by neutralizing caustic soda or soda carbonate with sulfuric acid, or is a by-product in the process of manufacturing human silk using the viscose method. be done.

In the oxygen absorbent of the present invention, the ratio of ferrous acetate to sodium sulfate 10A<salt can be freely changed depending on the desired characteristics of the oxygen absorbent.

In other words, if you want to increase the oxygen absorption rate, acetic acid
It is sufficient to increase the amount of sodium sulfate salt relative to iron, and conversely, if the oxygen absorption rate is to be decreased, the ratio of sodium sulfate salt relative to ferrous acetate may be reduced. Usually per 1 part by weight of ferrous acetate, 10 parts of sodium sulfate
71<. 0.01 parts by weight or more of salt, preferably 0.05 parts by weight
When the amount is at least 0.1 part by weight, particularly preferably at least 0.1 part by weight, a sufficient oxygen absorption effect can be achieved. On the other hand, if the mixing ratio of 1 part sodium sulfate salt is too large, the amount of oxygen absorbed per unit weight of the oxygen absorbent will decrease, so the upper limit is self-limited. Usually, the amount of sodium sulfate 107k salt per 1 part by weight of ferrous acetate is 10 parts by volume or less, preferably 5 parts by volume or less, particularly preferably 2 parts by volume or less. The filler in the present invention can disperse ferrous acetate and sodium sulfate well, can appropriately control the oxygen absorption amount and oxygen absorption rate, and also improves the air permeability of the oxygen absorbent itself. It has this effect.

Such fillers are themselves chemically inert, such as ferrous acetate or sodium sulfate,
In particular, those that are insoluble or poorly soluble in water are excellent.

Examples of fillers include activated carbon, diatomaceous earth, zeolite, kaolin, activated clay, silicon carbide, silicon nitride, colloidal silica, graphite, magnesium oxide, α
- Inorganic fillers such as β- or γ-alumina, silica alumina, anhydrous silica, mica, glass powder, and iron oxide; Examples include organic fillers such as various phthalates, cellulose, and synthetic resin powder (e.g., polyaraphamide powder). . The filler is a total of 1 ferrous acetate and sodium sulfate decahydrate.
0.001 parts by weight or more, preferably 0.001 parts by weight.
It is advantageous to use 0.01 parts by weight or more. The upper limit of the amount of filler to be used is limited by the fact that if it is used in too large a quantity, the amount of oxygen absorbed per unit weight of the oxygen absorber will decrease and become economically undesirable, but in general, ferrous acetate and sodium sulfate 10A It is sufficient that the amount is 5 parts by weight or less, preferably 2 parts by weight or less, particularly preferably 2 parts by weight or less, per 1 part by weight of the total salt. In the present invention, the oxygen absorbent may be in any form.

For example, ferrous acetate, sodium sulfate 1071<. The salt and filler can be made into fine powders and simply mixed together, or they can be ground and mixed using a mortar, agate bowl, sieve machine, ball mill, gearcon powder, internal mixer, etc. It can be used as a powder, or it can be formed into pellets, pieces, rods, blocks, sheets, etc. by using a tablet machine, extrusion molding machine, roll molding machine, etc. It may be. At that time, binders and lubricants that are commonly used in powder molding can also be used. Examples of the binder include starch, carboxymethyl cellulose,
Examples include high molecular weight polymers such as polyvinyl acetate, polyolefin, and polyvinyl alcohol, and examples of lubricants include various stearic acid derivatives. The oxygen absorbent of the present invention can be used in powder form or as is after being molded as described above, or it can be used in a bag made of breathable packaging material, such as cellophane, various synthetic resin films, paper, etc. You can also do that. The material and structure of the packaging material can be varied as long as it is breathable. The oxygen absorbent of the present invention can remove oxygen or absorb acid. It can be used for purposes such as reducing the elemental content or detecting the presence of oxygen, and the amount used can be selected as appropriate depending on the purpose and application. Therefore, it can be advantageously applied to holding precision instruments that deteriorate or change in quality.

The present invention will be described in detail below with reference to Examples.

Example 1 1.0 q of ferrous acetate [Fe(AcO)2], 10 A of sodium sulfate < 1.0 da of salt, and 1.0 y of activated carbon were thoroughly ground in a nitrogen atmosphere to form a powder at 20°C with a partial pressure of 1 a.
20CC12 in 30 minutes when exposed to TM oxygen atmosphere
It absorbed 25cc of oxygen in an hour.

Comparative Example 1 1.0y of ferrous acetate [Fe(AcO)2] was thoroughly soaked in a nitrogen atmosphere in an agate pot and exposed to an oxygen atmosphere of 1 atm at 20'C, after 5 (2) hours. However, no substantial oxygen absorption was observed.

Also, ferrous acetate remains white, almost unchanged from when it was prepared)
It was hot. Examples 2 to 6 Ferrous acetate 1.0y1 Sodium sulfate 10A<salt 1.0y and the following fillers were added as shown in Table 1, and the oxygen absorption at each hour was measured in the same manner as in Example 1. , the results shown in Table 1 were obtained.

Claims (1)

[Claims] 1. An oxygen absorbent containing ferrous acetate, sodium sulfate decahydrate, and a filler.