JP2009078271A - Oxygen scavenger and method for manufacturing oxygen scavenger - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oxygen scavenger whose handling time can be prolonged and a method for manufacturing the oxygen scavenger. <P>SOLUTION: The oxygen scavenger is an oxygen scavenger that absorbs and removes oxygen in an atmosphere, and is constituted such that an inorganic compound having an oxygen absorption site caused by oxygen depletion and at least a part of the oxygen absorption site is temporarily blocked by a site blocking factor (for example, carbon dioxide that is a carbonyl group), and the handling time until it comes to function as an oxygen scavenger is improved. The oxygen scavenger is preferably manufactured by reducing and sintering an inorganic oxide powder at a temperature of 500°C or higher to form the oxygen absorption site caused by a reversible oxygen depletion and then desorbably blocking at least a part of the oxygen absorption site with a site blocking factor body. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an oxygen scavenger that absorbs and removes oxygen in an atmosphere and a method for producing the oxygen scavenger.

In recent years, in response to strong demands for food safety and quality maintenance, it has been carried out to suppress oxidative degradation of food by making the inside of a food packaging body for packaging food anaerobic.
Specifically, an oxygen scavenger that absorbs and removes oxygen in the atmosphere is placed inside the food packaging body together with the food, and residual oxygen inside the food packaging body is removed to eliminate the inside of the food packaging body. An oxygen state is performed. In addition, in an inert gas not containing oxygen, the food is packaged together with the oxygen scavenger in a food packaging body so as not to allow oxygen to enter the food packaging body, and the food packaging body includes A small amount of oxygen that permeates and penetrates into the inside is also removed by an enclosed oxygen scavenger.

  As described above, oxygen scavengers that remove oxygen in the atmosphere include organic materials and inorganic materials. From the viewpoint of cost, iron-based oxygen scavengers are inorganic materials. Agents are mainly used. As shown in the following chemical formula (1), this iron-based oxygen scavenger removes oxygen from the atmosphere by reacting iron with oxygen in the atmosphere together with slight moisture in the atmosphere. Yes.

Fe + 1 / 2H ₂ O + 3 / 4O ₂ → FeOOH (1)

However, when the conventional iron-based oxygen scavenger as described above is used, there are the following problems.
(1) Since a little water is required for the reaction with oxygen, the performance of conventional oxygen scavengers when storing foods that dislike water such as dried foods, electronic parts, solder powder, etc. There is a problem that cannot be fully demonstrated.
(2) When checking whether foreign materials such as metals are mixed in the food packaged with a conventional oxygen scavenger along with an inert gas in the package, a metal detector is added to the iron-based oxygen scavenger. Reacts, and there is a problem that a simple examination cannot be performed.
(3) There is a problem that it is rapidly heated by a microwave such as a microwave oven and ignites.

  For this reason, oxygen absorbers using inorganic oxides such as titanium oxide instead of iron-based oxygen absorbers have been proposed (Patent Documents 1 to 5).

  However, there is a problem that the oxygen absorbing ability using only an inorganic oxide such as titanium oxide is not sufficient for oxygen absorption.

  Then, in the said inorganic oxide, it discovered that cerium oxide was suitable as a deoxidizer instead of the said titanium oxide, and proposed previously (patent document 6).

  By the way, cerium oxide having oxygen deficiency due to reduction treatment has a very high activity, and there is a problem that it is ignited when exposed to air suddenly. For this reason, when users seal their products (for example, pharmaceuticals and foods), the time until the oxygen scavenger consisting of cerium oxide is sealed (handling time), oxygen absorption proceeds and the performance deteriorates. There is a problem in product application.

  Thus, there has been a strong demand for the appearance of oxygen scavengers that can increase the handling time when encapsulating the oxygen scavenger and can arbitrarily adjust the handling time.

JP 2005-104064 A JP 2005-105194 A JP 2005-105195 A JP 2005-105199 A JP 2005-105200 A JP 2007-185653 A

  This invention makes it a subject to provide the manufacturing method of the oxygen absorber and oxygen absorber which can lengthen handling time in view of the said problem.

  In order to solve the above-described problems, the present invention is an oxygen scavenger that absorbs and removes oxygen in a living environment atmosphere, and the oxygen scavenger is caused by reversible oxygen deficiency caused by forced extraction of oxygen. The present invention provides an oxygen scavenger characterized by being an inorganic oxide having an oxygen absorbing site and having at least a part of the oxygen absorbing site removably blocked by a site blocking factor body.

The present invention is an oxygen scavenger that absorbs and removes oxygen in the living environment atmosphere,
The oxygen scavenger is an inorganic oxide having an oxygen absorption site due to reversible oxygen deficiency caused by forced extraction of oxygen;
The starting point is the point in time when the atmosphere is released from an inert atmosphere to room temperature and atmospheric pressure, and in the relationship between the elapsed time from the starting point and the oxygen absorption (mL / g), When the time at the intersection X between the oxygen absorption line L1 and the oxygen absorption line L2 having a larger slope than the line L1 is defined as h, the oxygen scavenger is defined as the time from the start point to the time h. The present invention provides an oxygen scavenger characterized in that it has a handling time.

  The invention is also a method for producing the oxygen scavenger, wherein the inorganic oxide powder is reduced and calcined at 1000 ° C. or higher to forcibly extract oxygen to form an oxygen absorption site due to reversible oxygen deficiency, Then, the present invention provides a method for producing an oxygen scavenger, wherein at least a part of the oxygen absorption site is removably blocked by a site blocking factor body.

  The invention is another method for producing the oxygen scavenger, wherein the inorganic oxide powder is reduced and calcined at 1000 ° C. or higher to forcibly extract oxygen to form an oxygen absorption site by reversible oxygen deficiency. And providing a method for producing an oxygen scavenger, wherein hydrogen is removed by heat vacuum treatment, and then at least part of the oxygen absorption site is removably blocked by a site plugging factor body. is there.

  The present invention is still another method for producing the oxygen scavenger, wherein the inorganic oxide powder is reduced and calcined at 1000 ° C. or higher to forcibly extract oxygen, thereby providing an oxygen absorption site due to reversible oxygen deficiency. A method for producing an oxygen scavenger comprising: forming, then removing heat by heating in an inert gas, and then detachably blocking at least a part of the oxygen absorption sites by a site blocking factor body Is to provide.

  Furthermore, the present invention provides a deoxygenated package characterized in that the oxygen scavenger is included in a package having air permeability resistance.

  Furthermore, the present invention provides a deoxygenation functional film having a deoxygenation layer comprising the above deoxidizer.

  Furthermore, the present invention provides a deoxygenated resin composition, wherein the deoxidizer is dispersed or kneaded in a resin having oxygen permeability.

  According to the oxygen scavenger of the present invention, the oxygen absorption site due to oxygen deficiency is detachably blocked by the site blocking factor body, so that the handling time of the oxygen scavenger can be extended.

  Hereinafter, the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments and examples. In addition, constituent elements in the following embodiments and examples include those that can be easily assumed by those skilled in the art or those that are substantially the same.

  The inorganic oxide used in the present invention is in a state in which the sites of oxygen atoms in the crystal of the metal inorganic oxide are missing. This site can absorb oxygen. This oxygen absorption occurs in a living environment atmosphere. In the present specification, a high-temperature and / or high-pressure harsh atmosphere such as exhaust gas discharged from a power engine operating with fossil fuel is not included in this living environment atmosphere. Here, the living environment atmosphere refers to a general atmosphere when storing products such as foods, electronic parts, and pharmaceuticals. The atmospheric pressure includes, for example, a reduced pressure state (vacuum packaging or the like) in a product packaging, and a pressurized state (pressurization / heat sterilization in retort processing, packaging shape maintenance use, or the like). About temperature, about -50 degreeC (at the time of frozen storage) to 180 degreeC (retort processing of a foodstuff) is included. The atmosphere is not necessarily air, but may be purged with an inert gas such as nitrogen gas to reduce the oxygen concentration. The inorganic oxide used in the present invention is in an oxygen deficient state because oxygen is extracted from the crystal lattice by the reduction treatment of the inorganic oxide having no oxygen deficiency. The reduction treatment is performed in a strong reducing atmosphere in which the concentration of a reducing gas such as hydrogen gas, acetylene gas, or carbon monoxide gas is high and heat treatment is performed at a high temperature.

  It is known that there are two types of oxygen deficiency possessed by inorganic oxides: reversible deficiency and irreversible deficiency. The reversible defect is an oxygen defect of the inorganic oxide constituting the oxygen scavenger of the present invention, and is generated when oxygen is forcibly extracted by treatment under strong reducing conditions. A reversible defect is a defect in which oxygen can be taken into a deficient site. For example, when the inorganic oxide is cerium oxide, which will be described later, in cerium oxide having a reversible defect, an unbalanced state of charge due to lack of oxygen is reduced to a part of tetravalent cerium to trivalent. To compensate. Trivalent cerium is unstable and easily returns to tetravalent. Therefore, by incorporating oxygen into the deficient site, trivalent cerium returns to tetravalent, and the charge balance is always kept at zero.

On the other hand, an irreversible defect is formed by doping a metal inorganic oxide with an element having a valence lower than that of the metal. An irreversible defect, unlike a reversible defect, is not a defect caused by treatment under strong reducing conditions. The irreversible defect can be obtained, for example, by mixing an oxide of an element having a valence lower than the valence of the metal with a metal inorganic oxide and firing in the atmosphere. When the inorganic oxide is, for example, cerium oxide described later, the valence of cerium in cerium oxide having irreversible defects is all tetravalent. Therefore, oxygen is not taken into the deficient site. For example, when 20 mol% of Ca is dissolved in CeO ₂ (Ce _0.8 Ca _0.2 O ₂ ), the average cation valence is 4 × 0.8 + 2 × 0.2 = 3.6. The number of oxygen atoms for balancing this valence is 3.6 ÷ 2 = 1.8, and the number of necessary oxygen atoms is less than two. Oxygen deficiency occurs accordingly. However, this oxygen deficiency is not capable of absorbing oxygen. Thus, the irreversible defect is not caused by forced extraction of oxygen but is caused by charge compensation in the metal inorganic oxide.

  By the way, in addition to the metal inorganic oxide having reversible oxygen deficiency used in the present invention, an OSC (oxygen storage and release capability) material is known as an inorganic oxide capable of absorbing oxygen. OSC materials are often used as promoters for automotive catalysts. OSC material is a material that uses oxygen ion conductivity and valence change of rare earth elements of cerium oxide to take in oxygen from the atmosphere and at the same time release oxygen to keep the amount of oxygen in the atmosphere constant. is there. However, the uptake and release of oxygen by the OSC material occurs for the first time at a high temperature of several hundred degrees Celsius. Therefore, oxygen uptake and release by the OSC material does not occur in the living environment atmosphere in the atmosphere. This is because the OSC material does not have reversible oxygen deficiency in the living environment atmosphere.

  For example, when cerium oxide is used as the metal inorganic oxide, the oxygen absorption amount of the metal inorganic oxide having reversible oxygen deficiency used in the present invention is 5 to 37 mL / in an environment of 25 ° C. and 1 atmosphere. g, especially very high, close to the theoretical limit of 15 to 34 mL / g. The theoretical limit of oxygen absorption of cerium oxide having reversible oxygen deficiency is 37.2 mL / g.

The oxygen absorption is measured by the following method. 2 g of the oxygen scavenger that is temporarily blocked by the site blocking factor body so that the oxygen absorption site can be detached is taken and included in a package having a gas resistance (air resistance 10 to 1000000 seconds). The size of the package having air permeability resistance is not particularly limited as long as it can contain 2 g of the oxygen scavenger. Separately, a package having the same material, the same size, and the same air permeability resistance that does not contain an oxygen scavenger is prepared. Note that this operation is desirably performed under an inert atmosphere such as nitrogen or argon. Next, the produced package containing the oxygen scavenger is exposed to the atmosphere (25 ° C., 1 atm), and the weight is measured with a precision electronic balance (4 digits or more after the decimal point) at regular intervals. Since the increase in weight is due to the absorption of oxygen, the amount of absorbed oxygen can be determined using the gas equation of state. In order to correct the weight increase due to moisture adsorbed on the package itself, the weight of the package not containing the oxygen scavenger is also measured at the same time, and the weight of the package containing the oxygen absorber is measured. Subtract from weight. Here, the air resistance is measured in accordance with JIS P8117, which means the time until the air 100mL finishes transmission at pressure difference 1.23kPa an area of 0.000642m ^2.

The inorganic oxide used in the present invention is preferably any one of cerium oxide, titanium oxide, zinc oxide, or a mixture thereof.
In particular, it is preferable to use cerium oxide as an inorganic oxide, which has a large oxygen absorption ability alone. A specific element may be added to the inorganic oxide as described later. As an additive element, it is preferable to add an element in the vicinity of the ionic radius of the inorganic oxide. However, the additive element is not limited to this as long as the oxygen absorption amount is increased by the addition.

Here, in this embodiment, the case where cerium oxide is used as the inorganic oxide will be described below with reference to FIG.
As shown in FIG. 1 and the following formula (2), the high-temperature reduction-treated cerium oxide having oxygen vacancies causes oxygen to be forcibly extracted from the crystal lattice by the reduction treatment, resulting in an oxygen vacancy state (CeO _2-x ). Thus, an oxygen absorption site is provided. This oxygen deficient state is the above-described reversible deficiency. And since this oxygen absorption site reacts with oxygen in living environment atmosphere as shown in the following formula (3), the effect as an oxygen scavenger is exhibited. Since cerium oxide has a fluorite structure (Fluorite-Type), it is structurally stable and can stably hold an oxygen absorption site due to oxygen deficiency. Further, since the oxygen ion conductivity is high, oxygen can enter and exit to the inside, and the oxygen absorption ability is good.
CeO ₂ + xH ₂ → CeO _2−x + xH ₂ O (2)
CeO _2-x + (X / 2) O ₂ → CeO ₂ (3)

In the present invention, the activity is controlled by temporarily occluding the oxygen absorption site with a site-occluding factor body so as to be removable until the user starts using the site.
That is, the oxygen scavenger according to the present invention is formed by temporarily blocking at least a part of the oxygen absorption site so as to be removable by the site blocking factor body.
In the present invention, the term “temporarily occluded” means that “at least a part of the oxygen absorption site is temporarily occluded by the site occlusion factor body” means that an oxygen scavenger is produced and oxygen is added in a predetermined atmosphere. The oxygen absorption function at least after being placed in a package of a confectionery or the like (eg, in a package of confectionery, etc.) Time to show). Further, “desorbable” means that the site-occluding factor body blocking the oxygen absorption site of the oxygen scavenger can spontaneously desorb from the oxygen absorption site in the living environment atmosphere.
The site blocking factor is a low molecular compound having a carbonyl group such as carbon dioxide (CO ₂ ). The site blocking factor body may have one or more carbonyl groups. The site blocking factor body preferably has a molecular weight of 28 or more, particularly about 44 to 200. It is preferable that the site-occluding factor body easily becomes a liquid or a gas and does not decompose under coating treatment conditions such as 50 to 600 ° C. and 1 atm.

Schematically, as shown in FIG. 2, the surface of reduced cerium oxide (CeO _2-x ) having oxygen vacancies by reduction is coated with carbon dioxide (CO ₂ ) to attack oxygen (O ₂ ). Can be inhibited, activity can be reduced, and ignition can be suppressed. As shown in the figure, the coating of cerium oxide with carbon dioxide consists of (a) a coating derived from the binding of carbon dioxide to the oxygen absorption site of cerium oxide, and (b) carbon dioxide on the surface of cerium oxide. There are two types of coatings derived from mechanical adsorption. And the activity of cerium oxide can be temporarily reduced by either coating mode.

As a result, as shown in FIG. 3, in the conventional case where carbon dioxide (CO ₂ ) is not coated (indicated by a broken line in FIG. 3), when functioning as a deoxidizer, the oxygen absorption curve is Although ignition occurred as a result of sudden rises with the passage of time, in the case of the present invention (indicated by a solid line in FIG. 3), oxygen absorption is gradual until a predetermined elapsed time (that is, oxygen is initially for a while). ), And after a predetermined elapsed time, the oxygen absorption curve rises and functions as an oxygen scavenger.

As a result, carbon dioxide (CO ₂ ) is present around the cerium oxide, so that it does not absorb oxygen for a certain period of time. Therefore, until the user puts the oxygen scavenger into the package of his / her product and seals the package, the oxygen absorption function is suppressed, and handling time exists.

As shown in FIG. 4, the handling time means that the oxygen scavenger in an inert atmosphere is at room temperature (25 ° C., hereinafter the same as “normal temperature”) / normal pressure (1 atm, hereinafter “normal pressure”). ”Is the same as this.) The starting point is the time when it is released into the atmosphere, and the initial oxygen absorption is slow in the relationship between the elapsed time (h) from the starting point and the oxygen absorption (mL / g). When the time at the intersection X between the oxygen absorption line L1 in the state and the oxygen absorption line L2 having a larger slope than the line L1 is defined as h, the time is defined as the time from the start point to the time h. The slope of the absorption line L1 in the initial state is generally 3 mL / g / h or less, and the slope of the subsequent absorption line L2 is larger than that.
Here, the handling time for the user is preferably about 0.5 to less than 7 hours, more preferably about 1 to 2 hours.
Therefore, after the handling time has elapsed, the oxygen absorption capacity increases rapidly and functions as a deoxidizer.

FIG. 5 shows the relationship between the temperature (50 to 600 ° C.) and time when the reduced cerium oxide is treated with carbon dioxide (CO ₂ ).
As shown in FIG. 5, the ignition phenomenon was confirmed up to 2 hours at 50 ° C. and up to 1 hour at 100 to 200 ° C. Moreover, although it did not ignite at 400 degreeC for 3 hours or more, 500 degreeC and 600 for 1 hour or more, it whitened (it returns to cerium oxide without an oxygen deficiency) was confirmed.

Therefore, the processing temperature of carbon dioxide (CO ₂ ) is 3 hours or more at 50 ° C., 2 hours or more at 100 to 200 ° C., 5 minutes or more at 250 ° C. and 300 ° C., 30 minutes to 2 hours at 400 ° C., 30 hours at 500 ° C. It was confirmed that at least a part of the oxygen absorption site can be temporarily occluded by the site occlusion factor body so as to be removable.

Next, the relationship between carbon dioxide (CO ₂ ) treatment conditions and handling time will be described.
As shown in FIG. 5 described above, when the treatment temperature during the carbon dioxide (CO ₂ ) treatment is low (less than 1 hour at 200 ° C.), ignition cannot be suppressed, while when it is high (over 3 hours at 400 ° C.), white Therefore, the relationship between the carbon dioxide (CO ₂ ) treatment time (h) and the handling time at 200 ° C., 250 ° C., 300 ° C., 350 ° C., and 400 ° C. is determined. This is shown in FIG.

As shown in FIG. 6, at 200 ° C. (“×” in FIG. 6), the handling time could not be extended even after long-term treatment.
On the other hand, at 400 ° C. (“Δ” in FIG. 6), the whitening occurs, so that the handling time could not be extended even after long-term treatment.
On the other hand, it has been found that the handling time can be freely controlled in the carbon dioxide (CO ₂ ) treatment at 250 to 350 ° C. within 6 hours.

  Therefore, the handling time can be adjusted according to the user's request by arbitrarily adjusting the processing time within the temperature range.

FIG. 7 shows the relationship between the amount of oxygen absorbed and the elapsed time in 1 hour treatment, 2 hour treatment, 3 hour treatment, 6 hour treatment, and 12 hour treatment with a heating temperature in carbon dioxide (CO ₂ ) treatment of 300 ° C. Show.
Thus, it has been found that the handling time can be adjusted by increasing the processing time.

  Here, carbon dioxide is exemplified as the site-occluding factor body that occludes oxygen-absorbing sites formed in hydrogen-reduced reduced cerium oxide, but the present invention is not limited to this. 5 may be an organic compound having a carbonyl group.

  Specifically, for example, aldehydes such as acetaldehyde, benzaldehyde, cinnamaldehyde, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, esters such as methyl acetate, ethyl acetate, methyl salicylate, acetic acid, butyric acid, succinic acid, etc. Amides such as carboxylic acids, ethaneamide, benzamide, formamide and the like can be mentioned.

Since these are liquid, by heating the solutions and steam, the steam is introduced into carbon dioxide (CO ₂₎ in the apparatus at a predetermined temperature, by introducing a site occlusion factor of a carbonyl group to an oxygen-absorbing sites closed You just have to do it.

Further, as shown in FIG. 8 can confirm carbon dioxide (CO ₂₎ present on the cerium oxide surface by measuring the IR spectrum using FT-IR. The figure shows the difference of the IR spectrum before and after heating of the reduced cerium oxide in which the oxygen absorption site is temporarily blocked with CO ₂ compared with the background. Here, the background is an IR spectrum of a sample in a room temperature state in which reduced cerium oxide is treated with CO ₂ . In the state before heating, since no desorption of CO ₂ has occurred, there is no difference from the background, and the spectrum remains flat. On the other hand, after CO ₂ is desorbed by heating the sample, absorption by CO ₂ decreases, so when the background spectrum is subtracted from it, the difference from the background becomes a negative peak. appear. Specifically, it can be confirmed that the vicinity of about 2180 to 2100 cm ^{−1 and the} vicinity of about 2310 to 2390 cm ⁻¹ are decreased compared to the background. Absorption in the vicinity of about 2180 to 2100 cm ⁻¹ is absorption derived from carbon dioxide bonded to oxygen absorption sites of cerium oxide. This absorption is not observed with carbon dioxide in the normal state, but rather is close to the absorption of carbon monoxide. From this, it is considered that the carbon dioxide bonded to the oxygen absorption site of cerium oxide exists in a state close to that of carbon monoxide. Further, the absorption in the vicinity of about 2310 to 2390 cm ⁻¹ is absorption derived from carbon dioxide adsorbed on the surface of cerium oxide. This absorption is also observed in normal conditions of carbon dioxide. The IR spectrum shown in FIG. 8 and FIG. 9 to be described next was measured using FT-720 manufactured by Horiba Seisakusho under a helium flow. DRS method (Diffuse Reflectance Spectroscopy) was used for the measurement.

FIG. 9 shows a result of measuring an infrared absorption spectrum using FT-IR in a process in which cerium oxide whose oxygen absorption sites are blocked with carbon dioxide absorbs oxygen. Oxygen is absorbed at room temperature and pressure in the atmosphere. As is clear from this result, it can be seen that the absorption peak in the vicinity of about 2125 cm ⁻¹ decreases with time, in other words, with oxygen absorption. This means that carbon dioxide that has blocked the oxygen absorption site of cerium oxide is desorbed as cerium oxide absorbs oxygen.

By removing the remaining hydrogen from the reduced cerium oxide reduced by hydrogen before treatment with carbon dioxide (CO ₂ ) or the like, the handling time can be improved.
FIG. 10 is a graph showing the relationship between vacuum processing conditions and the amount of desorbed hydrogen during temperature-programmed desorption (TPD) measurement. FIG. 11 is a relationship diagram between the hydrogen desorption amount and the handling time.

As shown in FIGS. 10 and 11, compared to the case where the vacuum treatment is not performed, when the vacuum treatment is performed, hydrogen is desorbed and the carbon dioxide (CO ₂ ) treatment is performed efficiently, and the handling time is extended. It was confirmed that it was possible.
The TPD measurement was performed by increasing the temperature at 10 ° C./1 minute after 30 minutes had passed at a predetermined temperature (50 ° C.). The carrier gas was helium (He) at 50 SCCM.

Next, the mechanism of coating by the treatment with carbon dioxide (CO ₂ ) or the like in the present invention will be described.
FIGS. 12-1 to 12-3 show a reduction process of hydrogen from a state of cerium oxide (CeO ₂ ) before reduction, followed by a hydrogen removal process in a vacuum if necessary, and a carbon dioxide (CO ₂ ) process. The process up to the state of functioning as an oxygen scavenger is schematically shown.
FIG. 12A is a state before and after reduction.
As shown in “1)” shown in FIG. 12A, oxygen ions (O ²⁻ ) and cerium ions (Ce ⁴⁺ ) are regularly arranged before reduction.
When the reduction treatment is performed, an oxygen absorption site 101 that is an oxygen deficiency (indicated by a broken-line circle in the drawing) is generated as shown in “2)” in FIG. The small black circle is hydrogen. The reduction treatment is performed in a strong reducing atmosphere in which the concentration of a reducing gas such as hydrogen gas, acetylene gas, or carbon monoxide gas is high and heat treatment is performed at a high temperature. The reducing gas concentration is preferably not less than the lower limit of explosion to 100% by volume, more preferably 20% to 100% by volume. The treatment temperature is preferably 500 ° C or higher, more preferably 700 ° C to 1200 ° C, and still more preferably 1000 ° C to 1050 ° C. The strongly reducing atmosphere is generally atmospheric pressure, but pressure conditions may be used instead.

Next, in this embodiment, it is possible to perform a hydrogen removal treatment before the coating treatment with carbon dioxide (CO ₂ ).
“3-1)” illustrated in FIG. 12-2 indicates a state in which hydrogen is desorbed and removed by heating in vacuum.

Here, the desorption of hydrogen differs depending on the presence state of hydrogen in cerium oxide. FIG. 13 shows the temperature programmed desorption behavior of hydrogen in cerium oxide immediately after reduction.
As shown in FIGS. 13 and 14, [1] Hydrogen stagnating in the pores of cerium oxide (CeO ₂ ) is desorbed at a relatively low temperature (around 250 ° C.).
Further, as shown in FIG. 13, [2] hydrogen terminating the surface of cerium oxide (CeO ₂ ) is desorbed at around 350 ° C.
Then, hydrogen is present in the crystal of, as shown in FIG. 13 [3] Cerium oxide (CeO ₂₎ is desorbed at 400 ° C. vicinity. Since hydrogen is removed by appropriately heating in this way, the site blocking factor body easily comes into contact with the site 101 of “3-2” shown in FIG.

Then, as shown in “3-2” shown in FIG. 12B, the oxygen portion of carbon dioxide (CO ₂ ) that is the site blocking factor body 102 fits into the oxygen absorption site 101 by being heated moderately. (So-called capping phenomenon caused by a key and a keyhole), and both are firmly coupled.
In this state, it is commercialized as an oxygen scavenger and is managed under a predetermined atmosphere (for example, sealed and filled with an inert gas).

  Then, the oxygen scavenger managed under the specified atmosphere is opened on the user side, and it is inserted when sealing its own products (eg medicines, sweets, etc.) in sealed bodies (eg bags, containers, etc.) To do.

“4)” shown in FIG. 12-3 is a scene in which the function of such an oxygen scavenger is exhibited.
When the product (for example, medicine, confectionery) is sealed in a sealed body, oxygen present inside is introduced into the oxygen absorption site.
Then, as shown in “5)” shown in FIG. 12C, carbon dioxide (CO ₂ ), which is a site blocking factor body that is locally blocked by the introduced oxygen and is temporarily blocked. ) Is desorbed as CO ₂ or desorbed as CO, and the remaining oxygen (O) moves to an internal oxygen deficient site.

  Thereafter, as shown in “6)” in FIG. 12-3, oxygen (O) always propagates toward the inside, so that the oxygen deficient site is always present in the outermost layer, and oxygen present in the sealed body is reduced. It continues to absorb and exerts a deoxidation function.

  In this way, at least a part of the oxygen absorption site 101 which is the oxygen deficiency is temporarily blocked by the site blocking factor body 102, and thereafter reaches an oxygen atmosphere of a predetermined concentration functioning as a deoxidizer. When the ratio of oxygen deficient sites is reduced and oxygen is absorbed, the site occlusion factor body 102 that has clogged the oxygen absorption sites 101 that are oxygen deficient sites is removed. Reduction in ignition due to oxygen absorption can be suppressed. In addition, the handling time can be arbitrarily adjusted by combining the processing temperature and the time.

The manufacturing method will be described with reference to FIGS.
As shown in FIG. 15, the cerium oxide powder 200 is fired in a firing furnace 201 (300 to 1000 ° C .: 1 hour), and then reduced in a hydrogen atmosphere in a reduction firing furnace 202. Thereafter, the carbon dioxide (CO ₂ ) treatment device 203 performs CO ₂ coating treatment, and then the film pack treatment device 204 gives a film pack to obtain a deoxygenated package.

FIGS. 16A and 16B are the first production method of the present invention, which is a direct CO ₂ coating method.
CO ₂ gas is introduced into the carbon dioxide (CO ₂ ) processing apparatus 203 shown in FIG. 16A, and CO ₂ is directly processed into cerium oxide. The CO ₂ gas may be 100%, or one containing other gas in addition to CO ₂ may be used. Examples of other gases include inert gases such as nitrogen, argon, helium, and neon; water vapor; organic compound gases such as aldehydes having a carbonyl group, ketones, esters, carboxylic acids, and amides. it can. When the gas is an inert gas or water vapor, the ratio of the other gas can be about 50% by volume or less, and can be an arbitrary ratio of 0 to 100% by volume if the gas is an organic compound gas. . CO ₂ gas can be supplied in a circulating state. Alternatively, the treatment may be performed by leaving cerium oxide in a certain amount of CO ₂ gas atmosphere. In either case, the pressure can be normal pressure. When supplying CO ₂ gas in a circulating state, it is preferable to set the supply amount to 0.5 SCCM or more per 1 g of cerium oxide. However, if at least a part of the oxygen absorption site can be temporarily blocked by the site blocking factor body. There is no particular limitation.
As shown in FIG. 16-2, the temperature increase of the reduced cerium oxide is started from room temperature or a predetermined temperature after reduction (for example, 10 ° C./minute temperature increase), and a predetermined processing temperature (for example, 50 to 600 ° C.) The treatment is performed for a treatment time (0.5 to 12 hours), and at least a part of the oxygen absorption site is temporarily blocked with a site blocking factor body, and then the temperature is lowered and taken out at room temperature.

Figure 17-1, Figure 17-2 is a second manufacturing method of the present invention, after the hydrogen removal by heating vacuum treatment, carbon dioxide (CO ₂₎ is a method of coating.
As shown in FIG. 17A, first, using a heat vacuum processing apparatus 205, a vacuum degree is set to 76 mmHg or less by a vacuum pump 206, and vacuum heat treatment is performed at 400 to 800 ° C. for 10 minutes to 9 hours.
Thereafter, in the same manner as in the first manufacturing method, the temperature rise is started from room temperature or a predetermined temperature after vacuum heat treatment (for example, 10 ° C./minute temperature rise), and a predetermined treatment temperature (for example, 50 to 600 ° C.) The treatment is performed for a treatment time (0.5 to 12 hours), and at least a part of the oxygen absorption site is temporarily blocked with a site blocking factor body, and then the temperature is lowered and taken out at room temperature.

Figure 18-1, Figure 18-2 is a third manufacturing method of the present invention, after the hydrogen removal by heat treatment in an inert gas, carbon dioxide (CO ₂₎ is a method of coating.
As shown in FIG. 18-1, first, an inert gas (helium, argon, nitrogen, etc.) is introduced into the inert gas heat treatment apparatus 207, and heat treatment is performed at 400 to 900 ° C. for several hours (2 to 5 hours). Do. The inert gas can be supplied in a flowing state. Alternatively, the treatment may be performed by leaving cerium oxide in a certain amount of inert gas atmosphere. In either case, the pressure can be normal pressure. When supplying an inert gas in a circulating state, it is preferable to supply 0.5 SCCM or more per 1 g of cerium oxide. However, if at least a part of the oxygen absorption site can be temporarily blocked by the site blocking factor body. There is no particular limitation.
Thereafter, in the same manner as in the first production method, the temperature rise is started from room temperature or a predetermined temperature after the inert gas heat treatment (for example, 10 ° C./minute temperature increase), and a predetermined processing temperature (for example, 50 to 600 ° C.). ) And a treatment time (0.5 to 12 hours), at least a part of the oxygen absorption site is temporarily blocked with a site blocking factor body, and then the temperature is lowered and taken out at room temperature.

Such various carbon dioxide (CO ₂₎ coating treatment method, at least a portion of the oxygen-absorbing sites by temporarily occluded by site blockage factor body, it is possible to ensure the handling time with the risk of fire .

Furthermore, in the present invention, when adjusting the oxide with respect to cerium oxide having oxygen vacancies, a specific additive element is added to be substituted and dissolved to form a composite oxide, thereby greatly increasing the amount of oxygen absorbed. I try to let them.
As this specific additive element, for example, any one of yttrium (Y), calcium (Ca) and praseodymium (Pr) or a mixture thereof is desirable.
These additive elements are added during the production of cerium oxide powder to form a composite oxide together with cerium oxide.

The addition of this specific additive element increases the oxygen absorption amount as follows.
First, cerium oxide is usually 4+, but its valence changes to 3+ when it is reduced at a high temperature. With this change in valence, the ionic radius of cerium oxide expands and the crystal lattice itself expands. However, the yttrium, calcium, and praseodymium have an ionic radius smaller than that of the expanded 3+ cerium ion. By adding, expansion of the lattice can be suppressed. As a result, the crystal is stabilized and more oxygen vacancies can be retained.

  In addition, as addition amount, it is preferable to set it as 1-20 mol%. This is because if the amount is less than 1 mol%, the amount of the effect of addition is small.

  In general, when an element having no or little change in valence is added to cerium oxide, the effect of increasing the amount of oxygen absorbed is not exhibited, but the additive element (Y, Ca, Pr) having a specific ionic radius is not exhibited. This is because if the addition amount is up to about 20 mol%, the expansion suppressing function of the cerium oxide fluorite lattice is sufficiently exhibited, and as a result, the amount of oxygen absorbed can be increased.

On the other hand, in the case of compacts such as tablets and flakes, a compact is obtained by pressing a composite oxide powder with cerium oxide to which an additive element is added at a predetermined pressure (for example, 0.5 t / cm ² or more). After being manufactured and sintered at a temperature of 1000 ° C. or higher, for example, reduced and fired in a reducing gas stream such as hydrogen at 500 ° C. for 1 hour, and then treated with carbon dioxide (CO ₂ ) in the same manner as described above. It is possible to obtain a pressure-molded body in which at least a part of the oxygen absorption site is temporarily blocked with a site blocking factor body to improve the handling time.

  The oxygen scavenger produced in this way is used by being sealed by a treatment such as laminating with a known oxygen scavenging package such as a porous film that can permeate oxygen sufficiently and sufficiently.

  In the oxygen scavenger according to the present embodiment, oxygen can be significantly absorbed and removed from the atmosphere by reacting with oxygen in the atmosphere as shown in the chemical formula (2).

  For this reason, in the oxygen scavenger comprising the composite oxide mainly composed of cerium oxide according to the present embodiment, (1) since it can react with oxygen without requiring any water, for example, dry food, It can be used for storage in the case of things that dislike moisture such as electronic parts and solder powder. (2) Since cerium oxide is non-metallic, it is not detected by a metal detector, and foreign substances in food can be found using the metal detector. In addition, (3) since the characteristics of microwave resistance are excellent, the oxygen scavenger composed of cerium oxide can prevent heating in microwave cooking. Further, (4) the addition of an additive to cerium oxide increases the oxygen absorption amount, so that the oxygen absorption amount per unit weight can be significantly increased as compared with the case of cerium oxide alone.

  Therefore, according to the present embodiment, it is possible to provide an oxygen scavenger in which the oxygen absorption amount is increased as compared with the case of cerium oxide alone, which is an inorganic oxide.

Thus, according to the present embodiment, it is possible to provide a deoxidizing agent that exhibits a deoxidizing function using cerium oxide, which is an inorganic oxide, and a deoxidizing method in a sealed atmosphere.
Therefore, for example, pharmaceuticals, supplements, chemicals (for example, dyes, fragrances, lipids, enzymes, vitamins, fatty acids) or food materials that are easily oxidized, foods, precision machinery and parts thereof, semiconductor substrates, and the like can be stably stored. It becomes possible.

Moreover, as shown in FIG. 19, it is good also as a deoxidation functional film 20A. As shown in FIG. 19, the deoxygenation functional film 20A includes a deoxygenation layer 21 made of an oxygen scavenger that temporarily occludes at least a part of the oxygen absorption sites with a site occlusion factor, and the deoxygenation layer 21. A gas barrier layer 22 having an oxygen gas barrier property, and a gas easy permeable layer 23 having an oxygen gas easy permeability provided on the other surface side of the deoxidation layer 21. In addition, a deoxygenation functional film may be provided. Here, in FIG. 19, the code | symbol 25 illustrates oxygen. This deoxygenation functional film 20A is used so that the gas easily permeable layer 23 side (inside in FIG. 19) is directed to an atmosphere to be deoxygenated.
In FIG. 19, an outer layer 24 is provided outside the gas barrier layer 22 to protect the gas barrier layer 22.

  Here, as the deoxygenation layer 21, a resin containing an oxygen scavenger that temporarily occludes at least a part of the oxygen absorption sites with a site occlusion factor, for example, nonwoven fabric, polyethylene (ultra-low density polyethylene, low density Polyethylene, low density linear polyethylene, medium density polyethylene), polypropylene, polystyrene, ethylene-propylene copolymer, ethylene-propylene random polymer, ethylene-α olefin copolymer, ethylene-vinyl acetate copolymer, ethylene propylene rubber. Examples thereof include a single layer or a multilayer such as an ethylene-ethyl acrylate copolymer, but the present invention is not limited thereto.

  Here, as the gas barrier layer 22, a metal foil such as an aluminum foil, various resins such as polyethylene terephthalate, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, terephthalic acid-trimethylhexamethylenediamine condensation polymer, 2, 2 -Bis (p-aminocyclohexyl) propane-adipic acid copolymer, ethylene vinyl alcohol copolymer, nylon MXD (trade name), nylon 6 (trade name), nylon 6, 6 (trade name), acrylic resin, etc. Although what consists of a single layer or a multilayer can be illustrated, this invention is not limited to these.

Examples of the gas permeable layer 23 include various resins such as polyethylene (ultra low density polyethylene, low density polyethylene, low density linear polyethylene, medium density polyethylene), polypropylene, polystyrene, ethylene-propylene copolymer, ethylene. Examples include a single layer or multiple layers such as a propylene random polymer, an ethylene-α olefin copolymer, an ethylene-vinyl acetate copolymer, an ethylene propylene rubber, and an ethylene-ethyl acrylate copolymer. The present invention is not limited to these, and a layer made of fibers such as paper and nonwoven fabric can also be used.
In addition, the gas permeable layer 23 may use the function of a sealant layer (for example, a polyolefin such as PP or PE) in combination.

  Examples of the outer layer 24 include polyethylene, polypropylene, polyethylene terephthalate (PET), and nylon (trade name), but the present invention is not limited thereto.

Moreover, as shown in the deoxidation functional film 20B of FIG. 20, a buffer layer 27 may be provided between the deoxygenation layer 21 and the gas barrier layer 22 to impart adhesiveness and buffering properties to the film. .
Further, an advanced gas barrier layer 28 for oxygen gas may be provided between the gas barrier layer 22 and the outer layer 24 to improve the certainty of preventing the entry of oxygen gas from the outside.

  Here, examples of the buffer layer 27 include resins having a buffering action and an adhesive action such as polyethylene and polypropylene, but the present invention is not limited thereto.

  Examples of the advanced gas barrier layer 28 include various metal foils including aluminum foil, aluminum vapor deposition films, various oxide (silica, titania, zirconia, alumina) vapor deposition films and the like. It is not limited to these.

  By using a 6-layer deoxygenation functional film 20B as shown in FIG. 20, it is possible to improve the buffering effect and make it difficult for oxygen gas to enter from the outside, and to provide a film with higher added value. it can.

  Further, as shown in FIG. 21-1, the oxygen scavenger 30 in which at least a part of the oxygen absorption site is temporarily blocked with a site plugging factor body, and the oxygen scavenger 30 are packaged, and the air permeability resistance The deoxidized packaging body 32A may be configured from the packaging body 31 having the structure.

Further, as shown in FIG. 21-2, the oxygen absorber package in which the state of the oxygen absorber is confirmed by visually confirming the interior of a part or all of the wrapper 31 as a transparent window 32. It may be 32B.
This is because when the oxygen scavenger has oxygen deficiency before absorbing oxygen, it is black, but when oxygen is absorbed, it turns yellowish white. Accordingly, since the yellowish white color can no longer function as an oxygen scavenger, the soundness can be confirmed at a glance.

  In addition, as shown in FIG. 22, a deoxygenating resin composition 42 is prepared by dispersing or kneading a deoxygenating agent 40 in which at least a part of the oxygen absorption site is temporarily occluded with a site occlusion factor body in a resin layer 41. You may make it comprise.

The material constituting the resin layer 41 may be any material that can permeate oxygen, such as low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, propylene-ethylene copolymer, ethylene-vinyl acetate. Examples thereof include olefin resins such as copolymers, blends thereof, and styrene resins such as polystyrene, styrene-butadiene copolymers, and styrene-isoprene copolymers. These resins can be used alone or as a blend.
Using such a deoxygenated resin composition 42, for example, a resin tray may be molded to constitute, for example, a tray for transporting electronic components.

  Hereinafter, although one Example for confirming the effect of this invention is described, this invention is not limited to this Example.

<Adjustment of raw materials>
While stirring an aqueous solution in which ammonium hydrogen carbonate, ammonia, ammonium carbonate and oxalic acid are dissolved in water, a cerium nitrate aqueous solution is added dropwise to carry out reverse neutralization, and the resulting precipitate is washed with ion-exchanged water (in this example, 2 Filtered). Thereafter, the filtrate was dried (at 300 ° C. for 2 hours) to obtain cerium oxide (CeO ₂ ) powder (average particle size: about 0.5 μm).

  In this example, the powder (30 g) was fired at 1100 ° C. for 1 hour. Further, the reduction conditions were 1000 ° C. for 1 hour and 100% hydrogen gas at 400 SCCM flow. The pressure was normal pressure.

Thereafter, the reduced cerium oxide is allowed to stand in a carbon dioxide (CO ₂ ) treatment apparatus 203 shown in FIG. 16A, 100% CO ₂ gas is introduced into the treatment apparatus 203, and CO is introduced into the cerium oxide. Processed ₂ The circulation amount of CO ₂ gas was 800 SCCM. The pressure was normal pressure.
The temperature program started the temperature increase from room temperature (10 ° C./minute temperature increase), then reached the treatment temperature (300 ° C.), treated at 300 ° C. for 2 hours, and then allowed to cool naturally. A sample in which a part of the oxygen absorption site is temporarily blocked with an oxygen absorption factor body (in this case, CO ₂ ) is encapsulated in a package having air resistance (7500 seconds), and then the film is processed by the film pack processing apparatus 204. The pack was applied to obtain a deoxygenated package according to this example.
As a comparative example was not subjected to carbon dioxide (CO ₂₎ treatment.

The oxygen scavenger packaging bodies of the present example and the comparative example were opened in the air, and the handling time was measured.
As a result, the carbon dioxide (CO ₂ ) treated sample of this example did not ignite and had a handling time of 1.5 hours, but the comparative example without treatment had a handling time of 20 minutes. Not met and ignited again.
Therefore, it was found that the deoxygenated package treated with carbon dioxide (CO ₂ ) has a handling time of 0.5 hours or more and does not ignite, so that it is effective as an oxygen scavenger for pharmaceuticals and sweets, for example. .

  As described above, the oxygen scavenger according to the present invention can increase the handling time, and is therefore suitable for use in removing oxygen from food packaging, for example.

It is a crystal structure schematic diagram of cerium oxide. The periphery of the cerium oxide is a schematic diagram for carbon dioxide (CO ₂₎ treatment. It is a relationship figure of handling time (oxygen absorption elapsed time) and oxygen absorption amount of cerium oxide. It is a related figure of the elapsed time and oxygen absorption which show the definition of handling time. Carbon dioxide (CO ₂₎ is a graph showing the relationship between treatment temperature and the carbon dioxide (CO ₂₎ coating time. It is a graph showing the relationship between carbon dioxide (CO ₂₎ processing time and handling time. It is a graph showing the relationship between carbon dioxide (CO ₂₎ treatment temperature (300 ° C.) the oxygen absorption elapsed time processing time between the constant and the oxygen absorption amount. It is a chart figure of the infrared absorption spectrum using FT-IR of the cerium oxide which obstruct | occluded the oxygen absorption site with the carbon dioxide. It is a chart figure of the infrared absorption spectrum using FT-IR in the process in which the cerium oxide which obstruct | occluded the oxygen absorption site with the carbon dioxide absorbs oxygen. It is a related figure of vacuum processing conditions and the amount of desorption hydrogen at the time of TPD measurement. It is a relationship diagram of the amount of hydrogen desorption and handling time. From the state before reduction of cerium dioxide (CeO _2), a process schematic view after hydrogen reduction treatment. It is a process schematic diagram of hydrogen removal and carbon dioxide (CO ₂ ) coating treatment. It is a process schematic diagram from an oxygen absorption start to an oxygen absorption state. It is a figure of the thermal desorption behavior of hydrogen in cerium oxide immediately after reduction. It is a schematic diagram of hydrogen terminated in cerium oxide (CeO ₂ ) bulk. After reduction treatment the cerium oxide powder is a schematic diagram of carbon dioxide (CO ₂₎ treatment to manufacturing processes for obtaining a deoxidizing packaging. Direct carbon dioxide (CO ₂₎ is a process schematic diagram for performing the processing. It is a process diagram of carbon dioxide (CO ₂₎ heating time of the processing and the processing time. After heating vacuum treatment to hydrogen removal is a process schematic diagram for direct carbon dioxide (CO ₂₎ treatment. It is a process diagram of a heat vacuum treatment and carbon dioxide (CO ₂₎ heating time and processing time of the processing. After hydrogen removed by treatment inert gas heating is a process schematic diagram for direct carbon dioxide (CO ₂₎ treatment. It is a process diagram of the inert gas heat treatment carbon dioxide (CO ₂₎ heating time of the processing and the processing time. It is a schematic diagram of a deoxidation functional film. It is a schematic diagram of another deoxygenation function film. It is a schematic diagram of a deoxidation package. It is a schematic diagram of another deoxygenation package. It is a schematic diagram of a deoxidation resin composition.

Claims (26)

An oxygen scavenger that absorbs and removes oxygen in the living environment atmosphere,
The oxygen scavenger is an inorganic oxide having an oxygen absorption site due to reversible oxygen deficiency caused by forced extraction of oxygen;
An oxygen scavenger characterized in that at least a part of the oxygen absorption site is removably blocked by a site blocking factor body. In claim 1,
The oxygen scavenger, wherein the site blocking factor body is a material having a carbonyl group. In claim 2,
An oxygen scavenger having an absorption peak in the range of about 2180 to 2100 cm ⁻¹ in an infrared absorption spectrum using FT-IR. In claim 2,
An oxygen scavenger, wherein the material having a carbonyl group is carbon dioxide (CO ₂ ). In claim 2,
A deoxygenating agent, wherein the material having a carbonyl group is an aldehyde, a ketone, an ester, a carboxylic acid or an amide. In any one of claims 1 to 5,
The oxygen scavenger, wherein the inorganic oxide is any one of cerium oxide, titanium oxide, and zinc oxide, or a mixture thereof. In any one of Claims 1 thru | or 6,
Magnesium (Mg), calcium (Ca), strontium (Sr), lanthanum (La), niobium (Nb), praseodymium (Pr), yttrium (Y), or a mixture thereof is fixed to the inorganic oxide. An oxygen scavenger characterized by being dissolved. In claim 7,
An oxygen scavenger, wherein the total amount of the solid solution elements is 1 to 20 mol%. An oxygen scavenger that absorbs and removes oxygen in the living environment atmosphere,
The oxygen scavenger is an inorganic oxide having an oxygen absorption site due to reversible oxygen deficiency caused by forced extraction of oxygen;
The starting point is the point in time when the atmosphere is released from an inert atmosphere to room temperature and atmospheric pressure, and in the relationship between the elapsed time from the starting point and the oxygen absorption (mL / g), When the time at the intersection X between the oxygen absorption line L1 and the oxygen absorption line L2 having a larger slope than the line L1 is defined as h, the oxygen scavenger is defined as the time from the start point to the time h. Oxygen scavenger, characterized in that it has a handling time. In claim 9,
The oxygen scavenger, wherein the handling time is 0.5 hours or more and less than 7 hours. A method for producing the oxygen scavenger according to claim 1,
The inorganic oxide powder is reduced and fired at 500 ° C. or higher to forcibly extract oxygen to form an oxygen absorption site due to reversible oxygen deficiency, and then at least a part of the oxygen absorption site is desorbed by a site blocking factor body. A method for producing an oxygen scavenger, wherein the oxygen absorber is closed so as to be separable. A method for producing the oxygen scavenger according to claim 1,
The inorganic oxide powder is reduced and calcined at 500 ° C. or higher to forcibly extract oxygen to form an oxygen absorption site due to reversible oxygen deficiency, and then heat-vacuum to remove hydrogen, and then the oxygen absorption site A method for producing an oxygen scavenger, characterized in that at least a part thereof is removably occluded by a site occlusion factor body. A method for producing the oxygen scavenger according to claim 1,
The inorganic oxide powder is reduced and fired at 500 ° C. or higher to forcibly extract oxygen, form an oxygen absorption site due to reversible oxygen deficiency, and then heat-treat in an inert gas to remove hydrogen, A method for producing an oxygen scavenger, wherein at least a part of the oxygen absorption site is removably blocked by a site blocking factor body. In any one of claims 11 to 13,
The method for producing an oxygen scavenger, wherein the site blocking factor is a material having a carbonyl group. In claim 14,
A method for producing an oxygen scavenger, wherein the material having a carbonyl group is carbon dioxide (CO ₂ ). In any one of claims 11 to 15,
The method for producing an oxygen scavenger, wherein the inorganic oxide is any one of cerium oxide, titanium oxide, and zinc oxide, or a mixture thereof. In any one of Claims 11 thru | or 16,
Magnesium (Mg), calcium (Ca), strontium (Sr), lanthanum (La), niobium (Nb), praseodymium (Pr), yttrium (Y), or a mixture thereof is dissolved in the cerium oxide. A method for producing an oxygen scavenger, characterized by comprising: In claim 17,
The method for producing an oxygen scavenger, wherein the total amount of the solid solution elements is 1 to 20 mol%. In any one of claims 11 to 13,
A method for producing an oxygen scavenger, characterized in that before the inorganic oxide powder is reduced and fired at 500 ° C. or higher, it is pressure-molded and sintered at 1000 ° C. or higher to obtain a molded body.   A deoxygenated package comprising the deoxidant according to any one of claims 1 to 10 enclosed in a package having air permeability resistance. In claim 20,
A deoxygenated packaging body, wherein at least a part of the packaging body having air permeability resistance is transparent.   A deoxygenating functional film comprising a deoxygenating layer comprising the deoxidizing agent according to any one of claims 1 to 10. In claim 22,
A gas barrier layer having an oxygen gas barrier property provided on one surface side of the deoxygenation layer, and an outer layer for protecting the oxygen gas barrier layer on the outside thereof;
A deoxidizing functional film, comprising: a gas permeable layer having oxygen gas permeable property provided on the other surface side of the deoxidized layer. In claim 23,
A deoxygenation functional film, wherein an advanced gas barrier layer for oxygen gas is provided between the gas barrier layer and the outer layer. In claim 23 or 24,
A deoxygenation functional film comprising a buffer layer provided between the deoxygenation layer and the oxygen gas barrier layer.   11. A deoxygenating resin composition, wherein the deoxidizing agent according to any one of claims 1 to 10 is dispersed or kneaded in a resin having oxygen permeability.