JPH0325221B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an oxygen absorber used for oxygen-free storage of foods, furs, clothing, etc. More specifically, 1,4,4a,9a-tetrahydroanthraquinone (hereinafter abbreviated as THAQ) and/or 1,4
This invention relates to an oxygen absorber containing dihydroanthraquinone (hereinafter abbreviated as DHAQ) as a main component. BACKGROUND ART Conventionally, in order to extend the storage period of food, etc., a method has been implemented in which food, etc. is placed in a sealed container and oxygen absorber is further enclosed in the container to remove oxygen from the air inside the container. Oxygen scavengers used in this method include those made by adding calcium hydroxide and activated carbon to hydrosulfite and further adding water, those made by adding metal halides, carriers, and water to metal powder such as iron, and others. ,
Hydroquinone, gallic acid, catechol, glucose,
Oxygen absorbers containing lignin, erythorbic acid, BHT, BHA, or ascorbic acid as main components have been proposed. has an adverse effect such as generating foul-smelling sulfur dioxide gas and leaving a residual odor on the object to be stored. There are drawbacks such as strong ones. As a result of intensive research into the development of oxygen scavengers that do not have these drawbacks, the present inventor discovered that THAQ and DHAQ
was found to be extremely effective as an oxygen scavenger, and the present invention was completed. THAQ or DHAQ can be used alone, but
Preferably THAQ is used, among which DHAQ
may be mixed. THAQ is obtained by the Diels-Alder reaction between naphthoquinone and butadiene. In the present invention, when THAQ and/or DHAQ is used as an oxygen scavenger, THAQ and/or DHAQ is used as a main component, and a basic substance and a carrier are added or mixed therewith, and more preferably, a mixture thereof is used. It is extremely effective to add or mix an aqueous medium and/or an organic solvent to the mixture to quickly absorb oxygen in the atmosphere. The reaction in which THAQ and DHAQ absorb oxygen is
It is assumed that the following formula applies. THAQ+1/20 ₂ = DHAQ+H ₂ O (1) DHAQ+1/20 ₂ = AQ+H ₂ O (2) (However, THAQ: 1, 4, 4a, 9a−THAQ,
DHAQ: indicates 1,4-DHAQ) The reaction of formula (1) proceeds relatively easily, but the reaction of formula (2) tends to be relatively slower than the reaction of (1). Examples of basic substances include alkali metal or alkaline earth metal hydroxides, carbonates, bicarbonates, silicates, borates, sulfites, thiosulfates, tertiary phosphates, polyphosphates, and tripolysates. Examples include inorganic weak acid salts such as phosphates and organic weak acid salts, but carbonates are particularly preferred. in particular,
For example, sodium hydroxide, potassium hydroxide, calcium hydroxide, magnesium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium silicate, potassium silicate, sodium borate, potassium borate, sodium sulfite,
Potassium sulfite, sodium thiosulfate, sodium triphosphate, sodium phthalate, potassium phthalate, sodium citrate, potassium citrate,
Examples include sodium acetate, potassium acetate, sodium succinate, potassium succinate, sodium propionate, potassium propionate, sodium fumarate, potassium fumarate, sodium malate, potassium malate, and the like. In addition, alcoholates such as sodium ethoxide, quaternary ammonium hydroxide or its weak acid salts, amines, etc. may also be used, if necessary. Particularly preferred is sodium carbonate or potassium carbonate, which are inexpensive and easy to handle. The amount of these basic substances used should be more than the catalytic amount,
Usually 0.0001 to THAQ and/or DHAQ
It is selected from 10 times by weight, preferably 0.001 to 5.0 times by weight, and more preferably 0.01 to 2.0 times by weight. In the present invention, by using a carrier
It is extremely effective in increasing the contact area between THAQ and/or DHAQ and oxygen and reducing the amount of basic substances and media used. Examples of carriers include activated carbon, silica, silica gel, silica alumina,
Porous carriers such as zeolite and diatomaceous earth; other materials include pulp, soybean protein, popcorn powder, polyurethane, sawdust, and defatted sugars. In particular, a porous carrier, preferably activated carbon, is effective in effectively exhibiting the oxygen scavenging ability of THAQ and/or DHAQ. The amount of carrier used varies depending on the type of carrier, but
Typically 0.01 for THAQ and/or DHAQ
More than twice the weight, usually more than 0.1 times the weight and less than 10 times the weight,
Preferably it is 0.2 times or more and 8 times or less by weight, more preferably 0.3 times or more and 5 times or less by weight.
When the amount of carrier decreases, the oxygen scavenging ability tends to decrease when the amount of medium such as an aqueous medium used is relatively small. If the amount of carrier used is too large, the capacity per unit volume as an oxygen scavenger will decrease. In the present invention, the main component of the oxygen absorber is
In order to effectively exhibit the oxygen scavenging ability of THAQ and/or DHAQ, it is preferable to simultaneously contain a medium such as an aqueous medium and/or an organic solvent. Water is usually used as the aqueous medium, but salts or water-soluble organic solvents may also be dissolved therein. Alternatively, it may be moisture contained in a carrier or atmosphere, or moisture absorbed from objects such as foods, or it may be in the form of water of crystallization of the above-mentioned bases and other salts. Examples of compounds having water of crystallization include, for example, Na ₂ CO ₃・10H ₂ O, Na ₂ SO ₄・10H ₂ O
etc. can be mentioned. The amount of aqueous medium used is as water
It is usually 3 times or less by weight, preferably 2 times or less and 0.0001 times or more by weight, and more preferably 1 time or more and 0.001 times or more by weight relative to THAQ and/or DHAQ. As an organic solvent, use TAHQ and/or
or monohydric or polyhydric alcohols such as ethanol, propanol, ethylene glycol, propylene glycol, glycerin, pentaerythritol, trimethylolpropane, trimethylolethane, etc., which can dissolve DHAQ;
Ketones such as methyl ethyl ketone and methyl butyl ketone, esters such as ethyl acetate, benzene,
Examples include hydrocarbons such as toluene and xylene, preferably water-soluble solvents, and more preferably alcohols. Organic solvents can be used alone as a medium, but alcohols can be used together with an aqueous medium. The amount to be used is the same as that for the aqueous medium, but when added to the aqueous medium, it may be added in an amount of 0.001 times or more, preferably 0.05 times or more by weight, relative to the aqueous medium. The presence of organic solvents such as alcohols, even in very small amounts, dissolves THAQ and/or DHAQ one by one and diffuses onto the surface of the carrier to improve contact with air. and/or
It is presumed that this further promotes the reaction between DHAQ and oxygen. In addition, to promote the oxygen scavenging ability of THAQ and/or DHAQ, 1,4-naphthoquinone sulfonate, metal phthalocyanine compounds (sodium cobalt phthalocyanine sulfonate, etc.), iron salts (ferrous chloride, etc.), copper salts (ferric chloride, etc.), Redox catalysts such as copper, etc.) can also be used. The oxygen scavenger of the present invention can be produced by sequentially mixing THAQ and/or DHAQ, a basic substance, and a carrier;
It can be easily produced by sequentially mixing DHAQ, a basic substance, an aqueous medium and/or an organic solvent, and a carrier; Each is mixed with a predetermined amount of carrier, and the mixture is
If necessary, it may be compressed into tablets, granulated, or fixed as a powder to one or both sides of a sheet by a known fixing method such as adhesive or stamping, and then made into an oxygen permeable bag, such as a perforated polyethylene film laminated paper bag, or a polypropylene bag. , polybutadiene, polyester, polyvinyl chloride, cellophane, etc., or a laminate film thereof, or stored in a perforated container for use. When storing these encapsulants for a long period of time, it is preferable to cover them with a film that can block air.If the storage film is removed when used as an oxygen scavenger, the oxygen in the atmosphere can be easily removed. can do. In order to make the powder sticky, a water-soluble polymer compound may be added as a binder. Examples of the compound include sodium alginate,
Examples include CMC, hydroxymethyl cellulose, ethyl cellulose, propyl cellulose, starch, and polyvinyl alcohol. Hereinafter, it will be explained in detail using examples. Examples 1 to 3 and comparative examples THAQ 84% as main ingredient of oxygen scavenger,
Mix 10 g each of base agent-A containing 14.4% DHAQ with the basic compound, carrier, and water in the proportions shown in Table 1, put the mixture in a 4-liter glass container containing air, and store it at room temperature with oxygen. The amount of oxygen absorbed was measured using a measuring device. The results are shown in Table 1. In addition, in Table 1, the values are expressed in units of 1.0 g of the base agent.

[Table] Examples 4 to 10 Examples 1 to 3 were carried out in the same manner as in Examples 1 to 3, except that Na ₂ CO ₃ decahydrate was used as the basic substance and water. The results are shown in Table 2.

【table】

[Table] #: Silica gel powder Examples 11 to 12 The same method as Examples 4 to 10 was carried out except that the deoxidation time was changed, and the results shown in Table 3 were obtained. .

[Table] This example has a slightly higher absorption rate than the previous example, but this is thought to be due to changes due to room temperature, etc. The amount of THAQ in 1 g of the main ingredient A used in this example is 0.84 g, and assuming that it is oxidized to DHAQ, the theoretical oxygen consumption is 44.4 ml.
It is. Therefore, the amount of oxygen absorbed over 44.4ml is DHAQ
This is thought to be due to oxygen absorption. Examples 13 to 19 Examples 1 to 3 were carried out in the same manner as in Examples 1 to 3, except that sodium bicarbonate was used as the basic substance and water was not added, including sodium carbonate. The results are shown in Table 4.

[Table] As described above, a certain degree of deoxidizing ability was observed even when water was not added, and when sodium bicarbonate was used, the effect of generating carbon dioxide gas was observed.

Claims (1)

[Scope of Claims] 1. An oxygen scavenger characterized by containing 1,4,4a,9a-tetrahydroanthraquinone and/or 1,4-dihydroanthraquinone, a basic substance, and a carrier. 2. An oxygen scavenger containing 1,4,4a,9a-tetrahydroanthraquinone and/or 1,4-dihydroanthraquinone, a basic substance, a carrier, and an aqueous medium and/or an organic solvent.