JP2001314756A - Solid deoxidating agent and deoxidant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid deoxidating agent having an equal oxygen absorbing performance to the conventional deoxidant and capable maintaining the performance for a long time even when exposed in an atmosphere and to prevent the deterioration of the performance of the dioxidant and the remained one without using a specified automatic charger, when the dioxidant formed in a band shape is cut off to use. SOLUTION: This solid deoxidating body, in weight %, consists of iron powder of 50-99.6%, halogenated metallic salt of 0.1-5%, solute contents of water soluble binder of 0.3-40% and water of the remainder. Therein, one or two kinds of activated carbon of 0.1-10% and zeolite of 0.1-40% are preferably contained and all or one part of the surface is preferably covered with a plastic resin film. Further, this deoxidant is formed by storing the solid type deoxidating body into a packaging bag which is constituted of packaging material of one layer or more which are air-impermeable and thermally sealable and has an air-permeable hole on a seal part of the outer periphery and an air- impermeable part on the outer side thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deoxidizing agent used for deoxidizing various kinds of packaging containers, and more particularly, to a deoxidizing agent which is easily degraded by oxygen or a cosmetic which generates oxygen by a chemical reaction. The present invention relates to a deoxidizer used in a packaging container having a humidity of 80% or more.

[0002]

2. Description of the Related Art There is a problem that the quality of foods and the like which are susceptible to oxidative deterioration is changed by oxygen in the container during storage in a packaging container. Further, in some kinds of cosmetics, oxygen is generated due to a chemical change of the contents, and the container may swell.
As means for solving such a problem, oxygen is removed by loading a deoxidizer into a packaging container.
Most of the oxygen scavengers are usually filled with an easily oxidizable substance such as iron powder in a closed air-permeable packaging bag in powder form.

[0003] In this case, there is a danger that the packaging bag is broken during use and the powder jumps out of the packaging bag and contaminates the product. As a solution to this problem, a solid oxygen absorber such as a sheet is used. Proposed. Hereinafter, in the present specification, a solid oxygen absorber is referred to as a solid oxygen absorber, and one packed in a packaging bag is referred to as an oxygen absorber.

For example, Japanese Patent Laid-Open Publication No. Hei 8-217128 proposes a packing for a lid containing a solid oxygen absorber, and the oxygen absorber is formed by dispersing iron powder in a thermoplastic resin and solidifying it. Used. The examples disclose a method in which 100 parts by weight of iron powder and 100 parts by weight of polyethylene are mixed, heated and melted at 190 ° C., and extruded by an extruder. Had limitations.

Japanese Unexamined Patent Publication (Kokai) No. 59-213440 proposes a solid deoxygenated body in which a granular substance is impregnated with a solution or slurry of a metal halide and iron powder is adhered to the surface thereof to form a tablet. However, the amount of iron powder that can be attached is limited to 30 to 500 parts by weight, preferably 50 to 200 parts by weight, based on 100 parts by weight of the particulate material.
Japanese Patent Application Laid-Open No. Hei 7-227261 proposes an oxygen-absorbing sheet in which iron powder is fixed with a thermoplastic resin, but the content of iron powder is 30 to 85% by weight. Is considered impossible. These also had a limit in oxygen absorption.

When a large amount of an oxygen scavenger is used, a method is used in which the strips connected in a belt shape are cut into an automatic charging machine and loaded into a packaging container. In this case, the oxygen absorber absorbs oxygen in the atmosphere from the surface of the packaging bag, and its capacity decreases with time in the atmosphere. As a method for solving this problem, the following proposal has been made.

For example, in Japanese Patent Application Laid-Open No. 7-149374, a method is adopted in which oxygen is absorbed only from the cut surface of the seal portion as a double package in which a non-breathable layer and a breathable layer are stacked. The disadvantage of this method is that the cut surface is a double wrap bag with breathability, not a non-breathable bag. For this reason, when left in the air, oxygen is absorbed from the cut surface, and the capacity of the oxygen scavenger decreases with time.

In Japanese Patent Application Laid-Open No. Sho 60-217924, a method is used in which a non-breathable outer packaging portion is perforated before use as a belt-shaped double packaging bag. A disadvantage of this method is that it is necessary to provide a needle hole roll for forcing the needle hole. Also, in order to cut after drilling, if for some reason the oxygen scavenger has not been used up after drilling,
The oxygen scavenger is left in the air, and the oxygen absorbing ability decreases with time. When this oxygen absorber is used for preserving foods and the like, the preservability may be poor. In JP-A-2-128676, a method is used in which a non-breathable material is adhered onto a ventilation surface and peeled off before use. Disadvantages of this method are that a peelable material is required and that a peeling device needs to be installed.

[0009]

The conventional solid oxygen absorber as described above has a problem that the oxygen absorption is inferior to that of an oxygen absorber containing powder such as iron powder in a packaging bag. In addition, in cosmetics, etc., a solid oxygen absorber that combines the function of absorbing oxygen gradually generated by a chemical reaction for the purpose of preventing tube swelling and the function of reducing deterioration even if the tube is frequently removed and exposed to the atmosphere But there was no compact one that could meet the needs. Further, as described above, there remains a problem in solving the problem in the case where the oxygen-absorbing agent connected in a strip shape is cut and loaded into the packaging container.

The problem to be solved by the present invention is
To provide a solid oxygen absorber having the same oxygen absorption capacity as the oxygen absorber stored in the packaging bag and having a long oxygen absorption capacity even when frequently exposed to the air, and a belt-shaped oxygen absorber. When the oxygen-containing agent is charged into the packaging container while being cut off, the oxygen-absorbing ability is hardly reduced, and a special device is not required for automatic charging, and the oxygen-absorbing ability of the remaining oxygen-absorbing agent is not reduced.

[0011]

The solid oxygen absorber according to the present invention for solving the above-mentioned problems has an iron powder content of 50 to 9% by mass.
9.6%, metal halide salt: 0.1 to 5%, solute content of water-soluble binder: 0.3 to 40%, balance being water. And in the solid oxygen absorber of the present invention, activated carbon: 0.1.
It is preferable to contain one or two kinds of 1 to 10% and zeolite: 0.1 to 40%. Further, it is preferable that all or a part of the surface is covered with a plastic resin film.

The oxygen absorber of the present invention for solving the above-mentioned problems is composed of one or more layers of non-breathable and heat-sealing wrapping material, and one or two wrapping materials are provided on the outer peripheral sealing portion. The solid oxygen-absorbing body of the present invention is housed in a packaging bag having at least one vent hole and a non-venting portion outside thereof.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present inventors have found that when iron powder-based deoxidized powder is solidified with vinyl acetate-ethylene emulsion, a large amount of iron powder can be dispersed and solidified to form the powder. First, the solid oxygen absorber according to the present invention will be described. If the iron powder content is less than 50% (mass%, the same applies hereinafter), the amount of deoxidation is reduced, so the content is set to 50% or more. Deoxygenation with iron is expressed as _{Fe + 3 / 2H 2 O +} 3 / 4O 2 → Fe (OH) 3, the oxygen absorption amount is proportional to the amount of the iron powder. However, if it exceeds 99.6%, it is difficult to bind, and the solid maintenance strength is reduced to cause collapse, so that the content is set to 99.6% or less.
As the iron powder, reduced iron powder, sprayed iron powder and the like generally used as an oxygen scavenger are preferably used.

The metal halide salt is used for accelerating the oxidation reaction, and if it is less than 0.1%, the effect of accelerating the reaction cannot be obtained. Further, even if added in excess of 5%, the reaction promoting effect is not further enhanced, so that the content was set to 5% or less. As the metal halide salt, lithium chloride, magnesium chloride, potassium chloride, sodium chloride, ferrous chloride, ferric chloride, zinc chloride, calcium chloride and the like can be used.

The binder is used to connect the iron powder particles and solidify them. The binder is water-soluble, and is used in the form of an aqueous solution or emulsion, and is dried by a method such as heat drying after molding. By using the binder in the form of an aqueous solution or emulsion, the binder can be uniformly dispersed throughout, and can be solidified in a small amount. Further, by drying after forming and evaporating water as water vapor, a porous solid oxygen absorber having fine pores can be obtained.

As a water-soluble binder, for example, vinyl acetate, polyvinyl alcohol, lignin, alumina sol, starch and the like can be used. These are solute contents of 0.1.
If it is less than 3%, the binding power is weak and handling becomes difficult, so the content was made 0.3% or more. On the other hand, if it exceeds 40%, the amount of deoxygenation is reduced, so it is set to 40% or less. In conventional solid oxygen absorbers, when a water-soluble binder is used to solidify, during processing, raw materials such as iron powder cause an oxidation reaction due to moisture, and were not examined as causing performance deterioration. If it is within the range, it can be practically used.

Activated carbon and zeolite, which are added as required, are limited in content for the following reasons. Activated carbon promotes the ionization of iron to promote the oxidation reaction.
% Is preferable, and even if it exceeds 10%, the effect of promoting the reaction is not changed. Zeolite is used as a condition for maintaining the deoxygenation reaction, as a water-retaining effect for improving the air permeability inside the deoxidizer and for controlling the peripheral water vapor pressure.
More preferably, it is added in an amount of 5% or more, and if it is added in excess of 40%, the content ratio of iron powder decreases and the amount of oxygen absorbed decreases, which is not preferable.

The shape of the solid oxygen absorber according to the present invention may be any shape such as a granular shape, a disk shape, a sheet shape and a rod shape. The thickness in the case of a sheet is 1 to 10 mm, and the diameter in the case of a rod is 1
３０30 mm is practically preferable. A plastic resin film as a coating material for the solid oxygen absorber is applied as needed to suppress the permeation of oxygen to the oxygen absorber. Polyethylene, silicone elastomer, polypropylene,
Polystyrene, polymethylpentene, polybutadiene,
Polycarbonate or polytetrafluoroethylene can be used.

The resin membrane is obtained from the oxygen permeability of the resin membrane, the required rate of deoxidation, and the surface area of the solid oxygen absorber as follows.
Selected. Resin film oxygen permeability ^{(cc / m 2 · 24hr)} > required oxygen rate (cc / 24hr) / solid oxygen body surface area (m ²⁾

As described above, the oxygen permeability of the resin membrane is made larger than the value calculated from the required deoxidation rate and the surface area of the solid deoxidizer, taking into account the oxygen absorption efficiency of the solid deoxidizer. The oxygen permeability is 2,000 cc / m ² · 24 hr · atm to 200,00 in consideration of water resistance in practical use.
It is preferably 0 cc / m ² · 24 hr · atm (25 ° C., RH 0%), and the moisture permeability is 1 g / m ² · 24 hr · atm.
Desirably, it is 00 g / m ² · 24 hr · atm (40 ° C., RH 90%).

The effect of the present invention can be obtained without any particular limitation on the thickness of the coating material. However, due to the relationship between oxygen permeability and moisture permeability, the oxygen absorption reaction is not hindered by the infiltration of water around the environment. In order to maintain the oxygen absorption performance, the thickness should be 1 mm or less.

As the plastic resin film covering a part of the surface, a resin film having low gas permeability such as polyester can be used in addition to the above-mentioned materials preferable for the entire coating. This is because the permeation of oxygen can be controlled and controlled by the rate of covering the surface. Further, as shown in FIG. 1, the plastic covering shape is such that the entire surface of the solid oxygen absorber 1 is covered with a sheet-like plastic film 2 and joined by a heat seal part 3, and as shown in FIG. 2A and a plastic resin film 4 adhered to a part of the surface as shown in FIG. 2A. For the plastic resin film 4, for example, a thermoplastic resin or a thermosetting resin can be adopted.

Next, the oxygen scavenger of the present invention is obtained by accommodating the above-described solid oxygen absorber 1 of the present invention in a packaging bag 5 as shown in FIG. The packaging bag 5 is made of a heat-impermeable non-breathable wrapping material 6, and has one or two or more air holes 7 in a sealing portion on an outer edge and a non-air-permeable portion 8 on the outside thereof.

FIG. 3 shows the oxygen-absorbing agent of the present invention connected in a belt shape, which is cut off at a cutting position 9 and loaded into a packaging container together with foods. One side of the seal portion at the boundary between the oxygen absorbers has a ventilation hole 7 communicating with the inside of the packaging bag 5, and the other side has a non-ventilation portion 8.
By setting the cut position 9 on the vent hole 7,
As shown in FIG. 4, the separated oxygen scavenger allows the vent hole 7 to communicate with the atmosphere and have air permeability. On the other hand, the oxygen absorber left on the left side of the cutting position 9 in FIG. 3 has no air permeability due to the non-air-permeable portion 8, so that it does not absorb oxygen and does not deteriorate even if it is left in the atmosphere.

The non-breathable packaging material 6 has an oxygen permeability of 200 cc / m
^It is desirable that the temperature be less than 2.24 hr.atm (25 ° C, RH 0%),
Specifically, for example, a plastic film of polyester, polypropylene, nylon, or the like, a film coated with polyvinyldene chloride, a film obtained by evaporating aluminum, or the like can be used. When the material of the non-breathable packaging material 6 itself does not have heat sealing properties, a laminated film provided with a heat sealing layer is used.

In order to provide the heat-sealing portion with the ventilation hole 7 and the non-venting portion 8 outside thereof, the heat-sealing device, for example, a heat-sealing bar or a heat-sealing die roll can be easily provided with a portion to which heat is not applied. . The ventilation hole 7 can be enlarged to such a size that the solid oxygen absorber 1 does not pass out of the packaging bag 5 so that a large air permeability can be obtained.

[0027]

EXAMPLES (Example 1) Inventive Example 1: Raw materials having the compounding ratio shown in Table 1 were kneaded with a water-soluble emulsion of vinyl acetate ethylene, extruded by an extruder, and formed into a rod having a diameter of 6 mm and a length of 10 mm. Molded. Then, it was dried by heating at 150 ° C. for 5 to 10 minutes to obtain a solid deoxygenated product. The surface of the solid oxygen absorber was coated with a composite film of perforated polypropylene and nonporous polypropylene film 5 μm (oxygen permeability 118,000 cc / m ² · 24 hr · at
m, and a water vapor permeability of 130 g / m ² · 24 hr · atm) and heat-sealed for coating. Comparative Example 1: A powder obtained by mixing raw materials having the compounding ratios shown in Table 1 was filled in a packaging material made of an oxygen-impermeable sheet in which a polyethylene film was laminated as a sealing material on a PET film and an oxygen-permeable sheet of polyethylene nonwoven fabric. And used as an oxygen scavenger.

As an evaluation 1, the coated solid oxygen absorber of Example 1 of the present invention and the oxygen absorber of Comparative Example 1 were sealed in a barrier bag at a relative humidity of 90% in the bag to improve oxygen absorption performance. Table 2 shows the results of the examination with time. Inventive Example 1 has an oxygen absorption amount per unit weight of 80% compared to Comparative Example 1.
There is no problem in practicality.

Table 3 shows the results of an oxygen-absorbed atmosphere having a relative humidity of 90% or more after being left for 48 hours and then put in a similar bag and examined for oxygen absorption. In Comparative Example 1, the oxygen absorption capacity was significantly deteriorated, and the oxygen absorption amount after 960 hours was 68% of that in Table 2.
In contrast, in Example 1 of the present invention, the attenuation was only 7%, indicating that the deterioration of the oxygen absorbing ability was significantly suppressed.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

Example 2 Inventive Example 2: Raw materials having the compounding ratio shown in Table 4 were kneaded with a water-soluble emulsion of vinyl acetate ethylene, extruded by an extruder, and formed into a sheet having a thickness of 3 mm. This was cut into 10 mm × 10 mm and dried by heating at 150 ° C. for 5 to 9 minutes to obtain a solid deoxygenated product. The surface of this solid oxygen-absorbing material was coated with a perforated polypropylene and a non-porous polypropylene film 5 μm composite film (oxygen permeability 118,000 cc).
/ m ² · 24hr · atm, moisture permeability ^{130 g / m 2 · 24hr ·} atm)
And heat sealed. Comparative Example 2: Powder mixed with the raw materials having the compounding ratios shown in Table 4 was filled in a packaging material made of an oxygen-impermeable sheet in which a polyethylene film was laminated as a sealing material on a PET film and an oxygen-permeable sheet of polyethylene nonwoven fabric. And used as an oxygen scavenger.

In Evaluation 2, the coated solid oxygen absorber of Example 2 of the present invention and the oxygen absorber of Comparative Example 2 were sealed in a barrier bag at a relative humidity of 90% in the bag to improve oxygen absorption performance. Table 5 shows the results of the examination with time. Inventive Example 2 had no problem because the oxygen absorption amount per unit weight was as large as 86% as compared with Comparative Example 2, and there was no problem.

Table 6 shows the results of examining the amount of oxygen absorbed in the same bag after standing in an oxygenated atmosphere having a relative humidity of 90% or more for 48 hours. In Comparative Example 2, the oxygen absorption capacity was significantly deteriorated, and the oxygen absorption amount after 960 hours was 71% of that in Table 5.
In contrast, in Example 1 of the present invention, the attenuation was only 13%, indicating that the deterioration of the oxygen absorbing ability was significantly suppressed.

[0036]

[Table 4]

[0037]

[Table 5]

[0038]

[Table 6]

Example 3 Invention Example 3: Binders and raw materials having the compounding ratios shown in Table 7 were kneaded with each binder in the form of a water-soluble emulsion, extruded by an extruder, and extruded to a thickness of 3 to 5 mm. It was formed into a sheet. This was cut into 10 mm × 10 mm and dried by heating at 150 ° C. for 5 to 10 minutes to obtain a solid deoxygenated product. This solid oxygen absorber,
A bag was formed using a packaging material in which 15 μm thick polypropylene was coated with polyvinyl chloride and a 12 μm thick polyethylene laminated, and the size of one piece was 70 mm × 50 mm.
And stored in a four-sided seal packaging bag as an oxygen scavenger.

Evaluation 3 was that the oxygen scavenger of Inventive Example 3 was left in an atmosphere having a relative humidity of 90% or more for 24 hours.
A sample without standing was prepared, and after completion of the standing, the sealing portion of the packaging bag was cut at a portion corresponding to the air hole to give air permeability, and sealed in the bag in the same manner as in Evaluation 1 to examine oxygen absorption performance. Table 8 shows the results. As is clear from this, since it is wrapped in a non-breathable wrapping material, the amount of oxygen absorbed does not attenuate even if it is left for 24 hours. In this case, the ventilation holes can sufficiently exhibit oxygen absorption performance.

[0041]

[Table 7]

[0042]

[Table 8]

[0043]

The solid oxygen absorber according to the present invention contains an appropriate binder in a small amount, so that the oxygen absorbing capacity is practically sufficiently maintained and solidification is easy. An oxygen scavenger is obtained. Further, those whose surfaces are covered with a plastic resin film can withstand standing in an aerobic atmosphere for a long time. Therefore, the solid oxygen absorber according to the present invention can be used for a container that requires oxygen removal and has a small space for enclosing the oxygen absorber, or a container in which oxygen repeatedly flows.

Further, in the oxygen absorber of the present invention, the packaging material of the packaging bag is non-permeable and has a ventilation hole at the outer peripheral seal portion and a non-venting portion outside the sealing portion. As a result, there is no deterioration in the performance of the oxygen scavenger, and there is no restriction on the time during which it can be left in the atmosphere. Further, when the oxygen absorber connected in a strip shape is used separately, the oxygen absorber does not enter the packaging bag with the unused oxygen absorber by separating the oxygen absorber at the air hole. At the time of automatic feeding, a feeding machine having a normal cutting function can be used without modification.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of the solid oxygen absorber according to the present invention.

FIGS. 2A and 2B are cross-sectional views showing another example of the solid oxygen absorber of the present invention.

FIG. 3 is a sectional view showing an example of the oxygen scavenger of the present invention.

FIG. 4 is a plan view showing an example of the oxygen scavenger of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Solid oxygen absorber 2 ... Plastic film 3 ... Heat seal part 4 ... Plastic resin film 5 ... Packaging bag 6 ... Non-breathable packaging material 7 ... Vent hole 8 ... Non-breathable part 9 ... Cutting position

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3E067 AA11 AB81 AB96 BA31A BB16A CA24 EA09 EE25 FA01 FB10 FC02 GB13 4B021 LA01 MC04 MK08 MK10 MK14 MP07 MQ04 MQ05 4D020 AA02 BA04 BA06 BA07 BA21 BB01 CA04 4G066 AADAAC12AC CA37 DA03 DA20 EA07 FA02 FA27 FA34 FA37

Claims (4)

[Claims] 1. In mass%, iron powder: 50 to 99.6%, metal halide salt: 0.1 to 5%, solute content of water-soluble binder: 0.3 to 40%, balance: A solid oxygen absorber consisting of water. 2. The method according to claim 1, further comprising one or two of activated carbon: 0.1 to 10% and zeolite: 0.1 to 40%.
The solid oxygen absorber according to the above. 3. The solid oxygen absorber according to claim 1, wherein the whole or part of the surface is covered with a plastic resin film. 4. One or two or more layers of non-breathable and heat-sealing wrapping material, and one or two or more ventilation holes at the outer edge seal portion and a non-ventilation portion outside thereof. An oxygen absorber comprising the solid oxygen absorber according to claim 1, 2 or 3 housed in a packaging bag.