JPH044225B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a packaging material for an oxygen absorber, and more specifically, the present invention relates to a packaging material for an oxygen absorber, and more specifically, a packaging material comprising a non-breathable outer material, a heat-sealing layer, a breathable inner material layer, and a breathable heat-sealing layer. This invention relates to a packaging material for an oxygen absorber that is adhesively bonded and allows ventilation to pass through the cut surface of the packaging material and through the inner surface. [Prior Art] Conventionally, breathable packaging materials have been used to package various drugs such as desiccants, insect repellents, oxygen scavengers, and freshness-preserving agents. In some cases, important requirements for breathable packaging materials include water resistance, breakage resistance, safety and hygiene, and food flavor retention in addition to breathability. For example, packaging materials for oxygen absorbers have traditionally been
A laminated adhesive of paper and perforated polyethylene film was used, and the air permeability in this case was adjusted by the porosity of the polyethylene film. However, when this oxygen absorber is applied to foods with a high moisture content, the packaging material has poor water resistance.
The moist oxygen absorber packaging bag may be damaged, or the contents may seep through the holes in the perforated polyethylene film, which is unfavorable from a food safety and hygiene perspective.Furthermore, the rate of oxygen absorption is slow due to moisture. There were cases where it happened. Further, in adjusting the air permeability, there were drawbacks such as deformation of the air holes during thermal bonding during the production of packaging materials, making the air permeability unstable and causing variations in oxygen absorption rate. As a packaging material that improves the above drawbacks, JP-A-53
Japanese Patent Application No. 51096 discloses a packaging material in which two plastic films having different melting points are made with holes and are either stacked on top of each other or laminated and bonded with paper sandwiched between them. Furthermore, Japanese Patent Application Laid-open No. 56-124440 or Japanese Patent Application Laid-Open No. 56-124441 discloses a packaging material using a plastic film having holes in its surface. However, in these cases, the surface is made of plastic film, which improves water resistance compared to paper, but since there are many holes perforated to provide breathability, food products with a high moisture content are produced. When it comes into contact with food, the packaging material becomes wet and the contents ooze out, causing health and safety problems, and it is also weak in strength. Furthermore, since the packaging materials are thermally bonded or adhesives are used during the manufacturing process, there are also disadvantages such as holes being deformed and air permeability changing due to the influence of the adhesive. In addition, when applied to humid foods, the surface plastic film and paper peeled off, making it impossible to use it as a packaging material for oxygen absorbers or alcohol-based freshness-preserving agents. In addition, when oxygen absorbers and freshness-preserving agents using conventional packaging materials are applied to foods such as coffee, tea, grated yam kelp, and peanuts that require aroma retention,
Problems such as the scent changing or becoming weaker were pointed out. [Problems to be Solved by the Invention] An object of the present invention is to solve the above-mentioned problems of the conventional packaging materials for oxygen absorbers, and to solve the problems in terms of safety and hygiene even when the packaging materials for oxygen absorbers are applied to humid foods. The object of the present invention is to provide a food product which is free from the problem of oxidation, has high strength, has stable air permeability, and has excellent flavor retention of food products. [Means for solving the problem] A means for solving the above problem is to use a packaging material for an oxygen absorber that has an oxygen permeability of 1000 ml/m ² 24 hr.
A non-breathable outer material made of atm or less, a heat seal layer, a breathable inner material layer, and a breathable heat seal layer, a non-breathable outer material and a breathable inner material layer. A heat-sealing layer is disposed between the heat-sealing layer and a breathable inner material layer is disposed between the heat-sealing layer and the breathable heat-sealing layer. This allows ventilation to pass through the cut surface of the inner material layer and through the heat-sealing layer provided with air permeability. In the above solution, the packaging material for the oxygen absorber is made by laminating and adhering a non-breathable outer material, a heat-sealing layer, a breathable inner material layer, and a breathable heat-sealing layer. and,
Each layer has a structure in which non-breathable outer material/heat-sealing layer/breathable inner material layer/breathable heat-sealing layer are laminated and bonded in this order. That is, in the above solution, the oxygen absorber packaging material has a heat seal layer disposed between a non-breathable outer material and an air permeable inner material layer, and a heat seal layer that is provided with air permeability. The structure is such that the inner material layer having air permeability is arranged between the layers and the inner material layer is laminated and bonded. Examples of non-breathable external materials include films made of polyethylene terephthalate, polyamide, polypropylene, polycarbonate, cellophane or polyvinyl alcohol, various polyvinylidene chloride coated films, aluminum foil laminate films, and various aluminum vapor-deposited films. It will be done. Among these, polyethylene terephthalate film or polyamide film is preferred in consideration of strength, ease of manufacturing, etc. The thickness of the film constituting the non-breathable outer material is preferably 50 μm or less, particularly preferably 10 to 20 μm, from the viewpoint of ease of handling during manufacturing. The air permeability of the non-breathable outer film is 1000ml/
^m2・24hr・atm or less is preferable, 500ml/ ^m2・
Particularly preferred is 24 hours/atm or less. The heat-sealing layer is used to bond the non-breathable outer material and the breathable inner material layer when manufacturing packaging materials. As a heat seal layer,
For example, a plastic film or a heat sealant may be used. When a plastic film is used as the heat-sealing layer, a plastic film made of, for example, polyethylene, ethylene vinyl acetate copolymer, ionomer resin, polybutadiene, or polyvinyl chloride is used. When the heat-sealing layer is a plastic film, the thickness of the film is generally 10-70μ, preferably 15-40μ. In addition, when a heat sealing agent is used for the heat sealing layer, examples of the heat sealing agent include a normal hot melt agent, hot melt emulsion, ionomer latex, ionomer resin emulsion, polyethylene emulsion, or ethylene vinyl acetate copolymer. Emulsion etc. are used.
When the heat sealing layer is a heat sealing agent, the coating amount is generally 0.5 to 30 g/m ² , preferably 5 to 20 g/m ² . The heat-sealing layer is used by laminating or coating the material in close contact with the non-breathable outer material. The number of heat-sealing layers is not limited to one, but two heat-sealing layers may be used depending on the adhesion between the non-breathable outer material and the breathable inner material during bag manufacturing. be exposed. As the breathable inner material layer, for example, paper or nonwoven fabric is used. When paper is used as the breathable inner material layer, examples of the paper include Japanese paper, mixed paper such as rayon mixed Japanese paper,
It is possible to use any paper such as Western paper. Among these papers, Japanese paper or rayon-mixed Japanese paper is preferred in consideration of adhesion to external materials and air permeability. Furthermore, the basis weight of the paper used is preferably 15 to 100 g/m ² in the case of Japanese paper, for example. When using a nonwoven fabric as the breathable inner material layer, wet, dry, or spunbond nonwoven fabrics can be used as the nonwoven fabric, and various materials such as polyamide, polyethylene terephthalate, and rayon can be used. is exemplified. Note that in order to impart water repellency or oil repellency to these papers or nonwoven fabrics, it is possible to use paper or nonwoven fabrics coated with a water repellent or oil repellent. As the heat-sealing layer having air permeability, the same material as the heat-sealing layer but having air permeability is used. That is, a plastic film, a heat sealing agent, or the like is used as the material for the heat seal layer imparted with air permeability. When a plastic film is used as a material for the breathable heat seal layer, examples of the plastic film include plastic films made of polyethylene, ethylene vinyl acetate copolymer, ionomer resin, polybutadiene, polyvinyl chloride, etc. . In addition, when a heat sealing agent is used as a material for the heat sealing layer imparted with air permeability, examples of the heat sealing agent include ordinary hot melt agents,
Examples include hot melt emulsion, ionomer latex, ionomer resin emulsion, polyethylene emulsion, and ethylene-vinyl acetate copolymer emulsion. Examples of methods for imparting air permeability to the material used as the air permeable heat-sealing layer include a method of providing holes in a film material (the holes herein may also be referred to as "holes" in this specification); A method of laminating a film on Japanese paper, non-woven fabric, etc. by thermocompression bonding and creating cracks in the film to impart breathability, and a method of applying a heat sealing agent to the inside of the breathable inner material layer using a method such as pitan coating to make the film breathable. A method of forming a heat-sealing layer with a Among the methods of imparting breathability to the material used as the breathable heat-sealing layer, there is a method of making holes in the film material, for example, by making holes in the film material and then inserting the hole into the breathable inner material layer. A method of pasting the material, or a method of pasting it on an air permeable inner material layer and then drilling a hole, etc. are adopted. In the case of the method of attaching to the breathable inner material layer and then punching holes in the heat-sealing layer material, if there are no holes in the non-breathable outer material, the breathable inner material layer There is no problem even if there is a hole. It is generally preferable to have as many holes as possible for the purpose of imparting air permeability to the heat-sealing layer material, as long as it does not impede adhesion, and in this case the porosity is generally
It is 0.2 to 30%, preferably 1 to 20%. By the way, when it is necessary to reduce or increase the air permeability of a package using the packaging material for an oxygen absorber of the present invention, the porosity of the heat-sealing layer imparted with air permeability is lowered or increased, and the air permeability is increased. It is possible to achieve the objective by adjusting the quality or thickness of the material used for the inner material layer. In order to further increase the strength of the package using the packaging material for an oxygen absorber of the present invention, for example, split fibers may be placed between the inner material layer having air permeability and the heat sealing layer having air permeability, or It is also possible to adhere and laminate the film in close contact with the inside of the heat-sealing layer to which it has been applied. Moreover, in the packaging material for an oxygen absorber of the present invention,
Printing can be applied to the back side of the non-breathable outer material. Furthermore, it is possible to perform printing such as character printing on the back side of the non-breathable outer material and then perform solid printing. The oxygen absorber package using the oxygen absorber packaging material of the present invention is housed in a gas-barrier container or packaging material together with an article to be stored such as food, especially food for which aroma retention is important. The freshness of stored items can be maintained. As oxygen scavengers, sulfites, hydrogen sulfites,
Dithionite, hydroquinone, catechol, resorcinol, pyrogallol, gallic acid, longalitz, ascorbic acid and/or its salts, isoascorbic acid and/or its salts, sorbose, glucose, lignin, dibutylated hydroxytoluene, butylated hydroxyanisole, Oxygen scavengers containing ferrous salts or metal powders such as iron powder, carbon gas generating type oxygen scavengers, carbon dioxide gas absorbing type oxygen scavengers, etc. are used. [Operation] The solution described above operates as follows. (1) In the above solution, the packaging material for the oxygen absorber is
Non-breathable outer material, heat seal layer, breathable inner material layer, and breathable heat seal layer are combined into non-breathable outer material/heat seal layer/
Since it has a structure in which a breathable inner material layer and a breathable heat-sealing layer are laminated and bonded in this order, the outer surface formed from the non-breathable outer material of the packaging material does not have breathability. Ventilation is performed through the cut surface of the breathable inner material layer and through the heat-sealed layer provided with breathability. In the case of an oxygen absorber package using this oxygen absorber packaging material, oxygen absorption is performed through the cut surface of the breathable inner material layer and through the breathable heat seal layer. That is, oxygen absorption inside and outside the package is carried out along the route of the cut surface of the breathable inner layer → the breathable inner layer → the breathable portion of the heat seal layer. The air permeability of the oxygen absorber package is mainly controlled by the material and thickness of the breathable inner material layer, the cross-sectional area of the cut portion of the package, and the like. (2) In this way, ventilation of packaging materials for oxygen absorbers is
The air permeability of the package is stable with little variation because the air permeability is not achieved through holes on the surface as in the conventional case, but through the cut surface of the inner material layer having air permeability. In particular, when adjusting air permeability at a low air permeability level, compared to the method of adjusting the number of ventilation holes and porosity, which is done with conventional packaging materials, this packaging material for oxygen absorbers has a low air permeability level. Since it is possible to adjust the paper quality and thickness of the inner material layer, the breathability is stable with little variation. (3) Oxygen absorber packaging using this oxygen absorber packaging material uses a non-porous outer material that does not make holes, so the bag has high water resistance and the contents do not stain. I never take it out. Additionally, it is stronger and safer than conventional packaging materials, making it sanitary and safe. (4) This packaging material for oxygen absorbers does not use the method of creating holes on the outer surface like conventional ones, so when manufacturing the packaging material, the outer material without holes to the heatol layer are replaced with the breathable inner material. It is sufficient to simply laminate the material layer to the heat-sealing layer with breathability, and the constituent materials of each layer can be laminated and bonded at the same time, which simplifies the process and takes into account deformation of the holes in the heat-sealing layer. without need,
Processability and workability are improved. (5) Since this packaging material for oxygen absorbers has the above-mentioned layer structure, it has the advantage that oxygen absorber packaging bodies can be easily manufactured using the heat-sealing layer with air permeability as the heat-sealing surface. Automatic filling and packaging is possible, and the resulting oxygen absorber package has high heat-sealing strength. (6) When an oxygen absorber package using this oxygen absorber packaging material is applied to foods, etc. where scent is important, the surface of the package is non-porous, so the scent of the food will enter the bag. Because it is difficult to absorb and come into contact with the oxygen-absorbing composition contained therein, the fragrance does not change in quality or become weak due to adsorption, and has excellent fragrance retention. (7) This packaging material for oxygen absorbers can be printed on the back side of the non-breathable outer film, and the ink does not come into direct contact with food, making it sanitary and safe. Furthermore, if solid printing or concealment printing is applied on top of character printing,
Even if the contents ooze out onto the breathable inner material, the appearance of the package will not be impaired because of the solid printing or concealment printing. [Example] Next, the present invention will be explained in more detail with reference to Examples. Example 1 Thickness with one color each of text printing and white solid printing on the back side
A laminated film made by extruding and laminating PE (polyethylene, heat seal layer) to a thickness of 15μ on a 12μ PET (polyethylene terephthalate) film (non-breathable outer material), and Japanese paper with a basis weight of 50g/m ² (breathable (inner material layer with
% perforated polyethylene film (heat-sealing layer with air permeability) and a non-porous outer material/heat-sealing layer/inner material layer with air permeability/heat-sealing layer with breathability. A laminated packaging material with a width of 100 mm was prepared. The bursting strength of this packaging material was measured according to the method of JIS P-8112. The results are shown in Table 1. Next, this packaging material is guided to a three-sided seal automatic filling packaging machine, and 1.5 g of iron-based oxygen scavenger is filled inside the breathable heat-sealed layer while a bar heater is used from the outside of the non-breathable outer material. It was sealed and cut to obtain an oxygen absorber package with dimensions of 50 x 50 mm. Place this oxygen absorber package on hydrated cotton made by soaking 2 g of absorbent cotton in 10 ml of water, and place it on KOP with 500 ml of air.
It was sealed in a laminated film bag made of (polyvinylidene chloride coated stretched polypropylene)/PE and stored in a constant temperature bath at 35°C. The oxygen concentration was analyzed after 2 days, and the condition of the oxygen absorber was observed on the 14th day.
The results are shown in Table 1. Further, this oxygen absorber package was sealed in a KON (vinylidene chloride coated stretched nylon)/PE bag together with 50 g of putter peanuts and stored in a constant temperature bath at 35°C. After 30 days of storage, the package was opened and the scent retention effect was examined through a sensory test. The results are shown in Table 1. Comparative Example 1 A packaging material made by laminating pure white paper (basis weight 50 g/m ² ) and perforated polyethylene film with uniformly distributed pores of 1 mm in diameter and a porosity of 10% was used to remove iron. A 50×50 mm oxygen absorber package was obtained by filling 1.5 g of oxygen agent. The results of a test similar to that of Example 1 using this packaging material or oxygen absorber package are shown as Comparative Example 1 in Table 1 together with Example 1. Comparative Example 2 A PET film printed in the same manner as in Example 2 and Japanese paper with a basis weight of 20 g/m ² were extrusion laminated with the same PE as in Example 1 in between, and pores with a diameter of 0.4 mm were formed. Perforated laminate sheet with 200 holes per ^100m2 (A)
Then, PE film was laminated on Japanese paper with a basis weight of 20g/ ^m2 ,
A perforated laminate sheet (B) with 200 pores with a diameter of 0.4 mm ^per 100 cm2 is laminated and glued together with the paper side as the adhesive surface.
A laminated packaging material with a width of 100 mm was manufactured. Next, using this packaging material, 1.5 g of the iron-based oxygen absorber composition was filled to obtain a 50×50 mm oxygen absorber package.

[Table] Using the above packaging material or oxygen absorber packaging,
Comparative Example 2 shows the results of a test similar to Example 1.
They are shown in Table 1 together with Example 1. Example 2 Thickness with one color each of text printing and white solid printing on the back side
A laminated film made by extruding and laminating PE (heat sealing tank) to a thickness of 15μ on a 12μ PET film (non-breathable outer material), and Japanese paper (breathable inner material layer) with a basis weight of 50g/ ^m2 . , has uniformly distributed pores with a diameter of 1 mm, and a porosity of 10
% perforated polyethylene film (heat-sealing layer with breathability) and a non-breathable outer material/heat-sealing layer/inner material layer with breathability/heat-sealing layer with breathability. A laminated packaging material with a width of 120 mm was prepared. This packaging material is guided to a three-sided seal automatic filling packaging machine, and 4.0 g of carbon dioxide absorbing oxygen scavenger is filled inside the breathable heat-sealed layer while a bar heater is used from the outside of the non-breathable outer material. It was sealed and cut to obtain an oxygen absorber package with dimensions of 60 x 60 mm. This oxygen absorber package was sealed in an ON (stretched nylon)/aluminum/PE bag together with 10 g of roasted coffee powder and stored in a constant temperature bath at 60°C. Analyzing the oxygen concentration inside the bag after 7 days,
The package was opened and the scent retention effect was examined through a sensory test. The results are shown in Table 2. Comparative Example 3 Example except that the packaging material was a laminate of pure white paper (basis weight 50 g/m ² ) and a perforated polyethylene film having uniformly distributed pores of 1 mm in diameter and a porosity of 10%. A carbon dioxide absorbing type oxygen scavenger was obtained in the same manner as in 2. The results of the same tests and measurements as in Example 2 using this oxygen absorber package are shown as Comparative Example 3 in Table 2 together with Example 2. Comparative Example 4 Made by laminating a 12μ thick PET film and a 15μ thick PE film, uniformly distributed diameter 1
A porous laminated film with pores of 1 mm in diameter and a porosity of 4%, ^Japanese paper with a basis weight of 50 g/m2, and pores of 1 mm in diameter uniformly distributed and a porosity of 10
% perforated polyethylene film in a laminated structure of perforated PET/perforated PE/Japanese paper/perforated polyethylene film. An oxygen absorber was obtained. The results of the same tests and measurements as in Example 2 using this oxygen absorber package are shown in Table 2 as Comparative Example 4 together with the Examples. Comparative Example 5 Same as Example 2 except that the oxygen absorber package was not enclosed in the ON/aluminum/PE bag.

[Table] Comparative Example 5 shows the results of similar tests and measurements.
It is shown in Table 2 together with Example 2. Example 3 Thickness with one color each of text printing and white solid printing on the back side
A laminated film made by extruding and laminating PE (polyethylene, heat seal layer) to a thickness of 15μ on a 12μ PET (polyethylene terephthalate) film (non-breathable outer material), and a polyester nonwoven fabric with a basis weight of 70g/m ² (breathable inner material layer) and uniformly distributed pores with a diameter of 1 mm, with a porosity of 10
% perforated polyethylene film (heat-sealing layer with air permeability) and a non-porous outer material/heat-sealing layer/inner material layer with air permeability/heat-sealing layer with breathability. A laminated packaging material with a width of 100 mm was prepared. Using this packaging material, the heat-sealed layers that have been given breathability are placed facing each other, and an iron-based oxygen absorber is added inside.
1.5 g was filled and sealed from the outside of the non-breathable outer material with an impulse sealer to obtain an oxygen absorber package with dimensions of 50 x 50 mm. Place this oxygen absorber package on hydrated cotton made by soaking 2 g of absorbent cotton in 10 ml of water, and add 500 ml of air.
It was sealed in a laminated film bag made of KOP (polyvinylidene chloride coated stretched polypropylene)/PE and stored in a constant temperature bath at 35°C. The oxygen concentration after 2 days was analyzed, and the condition of the oxygen absorber was observed on the 14th day. The results are shown in Table 3. Also,
At the same time, seal the heat-sealed part of the oxygen absorber package by 15mm.
It was cut into widths and the heat seal strength was measured using a tensile strength tester. The results are shown in Table 4. Comparative Example 6 An unprinted 12μ thick PET (polyethylene terephthalate) film (non-breathable outer material) was coated with a 15μ thick film.
A laminated film made of extruded and laminated PE (polyethylene) with a thickness of 100 g/m ² and a polyester nonwoven fabric (breathable inner material) with a basis weight of 70 g/m 2 were prepared. The PE sides of this laminated film face each other, and the nonwoven fabric is sandwiched between only the heat-sealed part.
The inside was filled with 1.5 g of iron-based oxygen absorber and sealed from the PET film side with an impulse sealer to obtain an oxygen absorber package with dimensions of 50 x 50 mm. The results of a test similar to that of Example 3 using this oxygen absorber package are shown as Comparative Example 6 in Tables 3 and 4 together with Example 3.

【table】

〔Effect of the invention〕

The present invention has the following unique effects. The air permeability of the oxygen scavenger package of the present invention is stable with little variation. This air permeability stability is particularly remarkable when adjusting the air permeability at a low air permeability level because it can be adjusted by the paper quality and thickness of the air permeable inner material tank. An oxygen absorber package using this oxygen absorber packaging material has high water resistance, and the contents do not seep out. Moreover, since it is strong, it is sanitary and safe. When this oxygen absorber package is applied to food, the aroma does not deteriorate or become weak due to adsorption, and has excellent aroma retention. This oxygen absorber packaging material has a simple manufacturing process and is excellent in processability and workability. Furthermore, the oxygen absorber packaging material can be easily manufactured into an oxygen absorber package by using the heat-sealing layer provided with air permeability as a heat-sealing surface. The heat sealing strength of the obtained oxygen absorber package is also high. This oxygen absorber packaging material allows printing on the back side of the outer material and is sanitary and safe. Furthermore, it is possible to perform solid printing or concealment printing on top of character printing, and a good appearance can be maintained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the structure of one embodiment of the packaging material for an oxygen absorber according to the present invention. FIG. 2 shows a cross-sectional view of an oxygen absorber package formed with the heat seal layer 4 provided with air permeability inside the oxygen absorber packaging material according to one embodiment of the present invention. In the figure, 1 is a non-breathable outer material, 2 is a heat-sealing layer, 3 is a breathable inner material layer, 4 is a heat-sealing layer with breathability, 5 is a ventilation hole of 4,
6 represents a packaging material for an oxygen absorber, and 7 represents an oxygen absorber.

Claims (1)

[Claims] 1 A non-breathable outer material consisting of an oxygen permeability of 1000ml/ ^m2・24hr・atm or less, a heat-sealing layer, a breathable inner material layer, and a breathable heat-sealing layer. A heat-sealing layer is arranged between the outer material and the breathable inner material layer, and a breathable inner material layer is arranged between the heat-sealing layer and the breathable heat-sealing layer. 1. A packaging material for an oxygen absorber, which is made by laminating and bonding, and allows ventilation to pass through a cut surface of an inner layer having air permeability and a heat-sealing layer provided with air permeability.