JP7385274B2 - Packaging materials and their manufacturing method - Google Patents

Description

The present invention relates to a packaging material and a method for manufacturing the same, and more particularly to a packaging material for foods and the like and a method for manufacturing the same.

BACKGROUND ART In an effort to provide packaging materials, coating materials, etc. with new configurations that are safe and inexpensive with less environmental impact, packaging materials having a composition of a freshness-maintaining material shown in Patent Document 1 have been proposed.
To briefly explain the invention of Patent Document 1, it is generally not possible to coat materials containing resins that are insoluble in alcohol, and it is recalled that alcohol (organic solvent) is used as a binder for water-soluble CDs. Although it is difficult to do so, in Patent Document 1, the inventor's unique idea ignores the fact that CD is water-soluble and uses monohydric alcohol in the binder solution.

That is, in the invention of Patent Document 1, cyclodextrin is fixed by coating with an aqueous cyclodextrin solution, "monohydric alcohol", and a binder resin, and it is possible to make maximum use of the freshness maintenance effect of cyclodextrin. Furthermore, by using the above-mentioned cyclodextrin aqueous solution, "monohydric alcohol" and binder resin as binder components, it is possible to easily apply the freshness maintaining material and to achieve smooth coating. It is temporary.

Patent No. 6713116

On the other hand, when a food packaging material is obtained by coating a resin film (resin sheet) with the excellent freshness-keeping material composition of Patent Document 1 as described above, in other words, the coating layer of the freshness-keeping material of Patent Document 1 is coated with a resin film. If the entire surface or back surface of the resin film is formed into a coating layer, there was a concern that it would be difficult to ensure sealing strength because the freshness maintaining material of Patent Document 1 has a relatively high melting point.

For example, as shown in FIG. 4(C), when the resin film is used as a packaging bag, the coating layers (freshness maintaining layer 2) of the two resin films are faced to each other with the object m to be packaged in between. Generally, the ends of the two resin films are heat-sealed, or one resin film is rolled into a U-shape and the ends of the resin film are overlapped and heat-sealed (see FIG. 4). In each figure, S indicates a sealed portion, and k indicates an internal space of the packaging bag, that is, a storage space that accommodates the object m).

However, even if the resin film itself is melted by heating, the coating layer is difficult to dissolve, and it is difficult to heat-seal the coating layers that directly overlap each other.
That is, when coating a freshness-maintaining material on the innermost part that comes into contact with a packaged object such as food, there is a concern that simply using the freshness-maintaining material according to the invention of Patent Document 1 may not provide sufficient sealing strength during packaging. Ta.

On the other hand, the current product, the deoxidizer, is packaged with food and has a function, so it can be swallowed accidentally or requires an insertion process during the manufacturing process, and if there is an insertion error, quality deterioration will occur. There's a problem. Additionally, in order to control foreign matter contamination, there is a problem in that the deoxidizing agent cannot be used with a metal detector because it is a metallic composition.
For this reason, there has been a strong desire to maintain the freshness of packaged items using a freshness-maintaining material that does not have both of the above-mentioned problems.

Therefore, the inventors of the present invention have conducted extensive research to find out whether further improvements can be made in order to obtain the effectiveness of the above-mentioned freshness maintaining material while ensuring sealing strength.
Against this background, the present invention was completed to ensure practical sealing strength when coating a resin film (resin sheet) with the composition of the freshness maintaining material of Patent Document 1 and using it as a food packaging material. I made it possible.

The present invention comprises at least three layers, in order, a breathable sheet layer, a freshness maintaining layer, and a low breathable sheet layer, the breathable sheet layer having higher air permeability than the low breathable sheet layer, A packaging material is provided that is a resin layer having a lower melting point than the freshness maintaining layer.
Further, in the present invention, the freshness maintaining layer can provide a packaging material containing a cyclic oligosaccharide.
Furthermore, the present invention could provide a packaging material in which the cyclic oligosaccharide of the freshness maintaining layer includes an antioxidant functional material as a guest molecule.
Furthermore, the present invention can provide a packaging material in which the air permeable sheet layer has an oxygen permeability of 2000 cm 3 /m 2 ·24 h ·atm or more.
Furthermore, the above-mentioned breathable sheet layer was able to provide a packaging material which is a layer containing linear low-density polyethylene as a main component.
Further, in the present invention, it was possible to provide a packaging material in which the oxygen permeability of the low air permeability sheet layer is 200 cm 3 /m 2 ·24 h ·atm or less.
Furthermore, the present invention can provide a packaging material in which the low air permeability sheet layer is made of a plastic film containing aluminum.
Furthermore, in the present invention, the freshness-maintaining layer includes a freshness-maintaining material that maintains the freshness of fresh products such as fruits and vegetables by suppressing deterioration of the food products, and the composition of the freshness-maintaining material includes the cyclic oligosaccharide, i.e. The cyclodextrin is a host that does not include a guest molecule or a clathrate that includes a guest molecule, and the cyclodextrin contains α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin. Dextrin, branched beta cyclodextrin, methylated alpha cyclodextrin, methylated beta cyclodextrin, methylated gamma cyclodextrin, hydroxypropyl alpha cyclodextrin, hydroxypropyl beta cyclodextrin, hydroxypropyl gamma cyclodextrin, monochlorotriazino alpha cyclodextrin , monochlorotriazino β cyclodextrin, monochlorotriazino γ cyclodextrin, triacetyl α cyclodextrin, triacetyl β cyclodextrin, and triacetyl γ cyclodextrin.
The above-mentioned packaging materials include food packaging materials as packaging materials for foods, etc., and the above-mentioned foods such as fruits and vegetables include not only vegetables and other fresh products, but also processed products such as cooked products, sweets, and bread. For example, it includes fresh foods such as vegetables, fruits, potatoes, mushrooms, seaweed, meat, and fish, as well as prepared foods such as prepared dishes, processed foods such as ham, kamaboko, sweets, bread, and seasonings. The above-mentioned foods such as fruits and vegetables may be any food whose freshness decreases over time and whose freshness can be suppressed by the freshness-maintaining layer.
In addition to food, the above-mentioned packaging materials include bags for storing filth and waste that emit odors, in addition to foods. For example, the above-mentioned packaging materials include garbage bags for storing garbage. When the object to be packaged is filth or waste, the above-mentioned freshness maintenance (maintaining freshness) can be thought of as spoilage suppression and deodorization. In addition, the items to be packaged in the packaging material include drugs. For example, the above-mentioned packaged items include a fungicide for plastic greenhouses and the like, and a repellent for avoiding damage from birds and the like. Further, the above-mentioned packaging material may be a packaging material for a building material. When the above-mentioned packaging material is used as a packaging material for building materials, the above-mentioned freshness maintenance can be thought of as suppressing the propagation of mold, that is, an anti-mold effect. Furthermore, the above-mentioned packaging materials include those in which the object to be packaged is made of metal members, parts, or materials. When packaging metal with the above-mentioned packaging material, the above-mentioned freshness maintenance can be thought of as oxidation prevention.
Furthermore, in the present invention, the cyclodextrin includes alpha lipoic acid, metal, metal salt, metal oxide, biguanide, carbanilide, surfactant, carboxylic acid, alcohol, ammonium salt, phenol derivative, amino acid, iodine compound, coenzyme Q10, Curcumin, catechins, herbs, chlorophylls, DHA, EPA, 1-methylcyclopropene, chlorine, bromine, carbon dioxide ethanol, propanol, sodium linear alkylbenzene sulfonate, alkyl glycoside, alkylamine oxide, benzalkonium chloride, It was possible to provide a packaging material which is the above-mentioned clathrate containing at least one of benzethonium chloride, dialkyldimethylammonium chloride, polyoxyethylene alkyl ether acetic acid, oxalic acid, citric acid, butyric acid, and isovaleric acid.
Furthermore, the present invention provides a reinforcing sheet layer on the opposite side of the freshness maintaining layer of the low air permeable sheet layer, and a reinforcing sheet layer is provided between the freshness maintaining layer and the low air permeable sheet layer, and between the low air permeable sheet layer and the low air permeable sheet layer. It was possible to provide a packaging material that is a laminated film in which a laminated layer is interposed between each of the reinforcing sheet layers.
Further, in the present invention, the freshness maintaining layer is a first freshness maintaining layer, the laminate layer between the first freshness maintaining layer and the low air permeable sheet layer is a first laminate layer, and the low air permeable sheet layer The laminate layer between the reinforcing sheet layer and the reinforcing sheet layer is a second laminate layer, and a cyclic oligosaccharide is included between the first laminate layer and the low air permeability sheet layer, separately from the first freshness maintaining layer. We were able to provide packaging materials equipped with a second freshness-maintaining layer.
Furthermore, the present invention provides a first step of forming the breathable sheet layer and the freshness-keeping layer by coating the freshness-keeping material on a breathable sheet, and coating the freshness-keeping layer with one of the laminate layers. a second step of forming the low air permeability sheet layer by laminating the low air permeability sheet through a laminate material, and applying a laminate material to be another one of the laminate layers to the low air permeability sheet layer It was possible to provide a method for manufacturing packaging materials, which includes a third step of forming the reinforcing sheet layer by laminating the reinforcing sheet through the reinforcing sheet layer.
Still further, the present invention provides a bag-shaped packaging material that is provided with a sealed area and a non-sealed area that are not sealed in the breathable sheet layer, and that is sealed in the sealed area. The layer has a substantially uniform thickness that faces at least the entire non-sealed area without interruption, and the air permeable sheet layer has uniform air permeability in at least the entire non-sealed area. I was able to provide it.
Furthermore, the present invention provides at least three layers, in order from the inside of the package, a freshness maintaining layer, an air permeable sheet layer, and a low air permeable sheet layer, the freshness maintaining layer containing a cyclic oligosaccharide, and the air permeable The sheet layer includes a sealed area that is sealed and a non-sealed area that is not sealed, the non-sealed area being an area facing the freshness-keeping layer, and the non-sealing area being an area not facing the freshness-keeping layer. Therefore, it was possible to provide a packaging material in which the air permeable sheet layer is a resin layer having higher air permeability than the low air permeability sheet layer and a lower melting point than the freshness maintaining layer.
Furthermore, the present invention provides a bag-shaped packaging material sealed in the sealed area, wherein the entire inner surface of the bag that accommodates the object to be packaged is the non-sealed area, and the freshness maintaining layer is , it was possible to provide a packaging material having a layer having a substantially uniform thickness covering the entire non-sealed area for the item to be packaged.

The present invention is a packaging material equipped with a freshness-maintaining layer that fixes cyclodextrin by coating with an aqueous cyclodextrin solution, monohydric alcohol, and binder resin, and makes it possible to maximize the freshness-maintaining effect of cyclodextrin. Improved seal strength.
That is, the present invention makes it possible to provide practical sealing properties by using a packaging material having the above-mentioned configuration as a packaging material using the technique disclosed in Patent Document 1.
In other words, in order to enable long-term storage of food without impairing sealing performance, a freshness-keeping layer is provided on the inside of the breathable sheet layer (on the side of the packaged items) and on the outside of the freshness-keeping layer (on the side opposite to the packaged items). By arranging a low air permeability sheet layer with low oxygen permeability, the oxygen barrier properties can be improved.
In particular, in the present invention (claims 13 and 15), by forming the portion that performs the function of maintaining freshness as a continuous, uninterrupted freshness maintaining layer with a substantially uniform thickness, it is possible to Even if it is in a different position (even if it is displaced), it will always face the part that performs the function of maintaining freshness (through the breathable sheet layer or directly), and the freshness of the packaged items can be reliably maintained. . For example, even if the packaged item is at an uneven position within the package, almost the entire surface facing the packaged item through the breathable sheet layer can be made into a surface that exhibits the effect of maintaining freshness.
Further, in the present invention (claims 14 and 15), while ensuring sealing performance, the freshness maintaining layer is directly exposed to the packaged items without passing through the breathable sheet layer, thereby maximizing the effect of maintaining freshness. be able to.

(A) is an exploded perspective view of a packaging material according to one embodiment of the present invention, (B) is an exploded perspective view of a packaging material according to another embodiment of the present invention, and (C) is an exploded perspective view of a packaging material according to another embodiment of the present invention. (D) is an exploded perspective view of a packaging material according to yet another embodiment of the present invention. (A) to (D) are schematic cross-sectional views showing the manufacturing process of the packaging material of FIG. 1(A). FIG. 2 is an explanatory diagram showing examples and comparative examples of the present invention. (A) is an explanatory diagram showing a cross section of a main part of an embodiment of the packaging material according to the present invention, (B) is an explanatory diagram showing a cross section of a main part of another embodiment of the present invention, and (C) is a comparison diagram. An explanatory diagram showing a cross section of a main part of an example.

(overview)
The packaging material according to the present invention includes, in order from the inside of the package, that is, from the side of the packaged object such as food packaged in the packaging material, a breathable sheet layer 1, a freshness maintaining layer 2, and a low breathable sheet layer 4. It includes at least three layers (FIG. 1(A), FIG. 2(D), and FIG. 4(A)).
Here, an example of the packaging material according to the present invention as a food packaging material for packaging food will be shown.
The freshness-maintaining layer 2 contains a freshness-maintaining material that maintains the freshness of fresh products such as fruits and vegetables by suppressing their deterioration, and contains a cyclic oligosaccharide, that is, cyclodextrin as a composition of the freshness-maintaining material 2.
The air-permeable sheet layer 1 is a layer that covers the freshness-maintaining layer 2 facing the packaged object m side, and is a resin layer that has higher air permeability than the low-air permeability sheet 4 and has a lower melting point than the freshness-maintaining layer 2.

In this example, a reinforcing sheet layer 5 is provided on the side of the low air permeability sheet layer 4 opposite to the freshness maintaining layer 2. Furthermore, a laminate layer 3 is interposed between the freshness maintaining layer 2 and the low air permeability sheet layer 4, and between the low air permeability sheet layer 4 and the reinforcing sheet layer 5, respectively. That is, this packaging material is a laminated film. Hereinafter, the laminate layer 3 between the freshness maintaining layer 2 and the low air permeability sheet layer 4 will be referred to as the first laminate layer 3a, and the laminate layer 3 between the low air permeability sheet layer 4 and the reinforcing sheet layer 5 will be referred to as the first laminate layer 3a, as necessary. It is called a second laminate layer 3b.

(Freshness maintenance layer 2)
The cyclodextrin of the freshness maintaining layer 2 can be a host that does not include guest molecules or a clathrate that includes guest molecules. In addition, the above cyclodextrins include α cyclodextrin, β cyclodextrin, γ cyclodextrin, branched β cyclodextrin, methylated α cyclodextrin, methylated β cyclodextrin, methylated γ cyclodextrin, hydroxypropyl α cyclodextrin, hydroxypropyl At least one of β cyclodextrin, hydroxypropyl γ cyclodextrin, monochlorotriazino α cyclodextrin, monochlorotriazino β cyclodextrin, monochlorotriazino γ cyclodextrin, triacetyl α cyclodextrin, triacetyl β cyclodextrin, and triacetyl γ cyclodextrin. It is possible to use one or more of them.
Furthermore, the above-mentioned freshness maintaining material is a coating liquid, and the coating liquid for the resin or paper material contains a cyclodextrin aqueous solution prepared by dissolving cyclodextrin in water, a monohydric alcohol, and a binder resin.

Regarding the freshness-keeping layer 2, in this example, a layer in which an antioxidant functional material is included as a guest molecule in the above-mentioned cyclodextrin of the freshness-keeping layer 2 is used.
For example, the above antioxidant functional agents include alpha lipoic acid, coenzyme Q10, vitamin C, vitamin A, vitamin E, vitamin B12, catechins, polyphenols, inorganic selenium compounds, zinc inorganic compounds, iron inorganic compounds, copper Contains at least one of an inorganic compound, an organic selenium compound, an organic zinc compound, an organic iron compound, an organic copper compound, a selenium chelate compound, a zinc chelate compound, an iron chelate compound, and a copper chelate compound. A composition that can be used can be employed.
Desirably, as a component of the freshness maintaining layer 2, the above-mentioned cyclodextrin contains α-lipoic acid, a metal, a metal salt, a metal oxide, a biguanide, a carbanilide, a surfactant, a carboxylic acid, an alcohol, an ammonium salt, a phenol derivative, an amino acid, Iodine compounds, coenzyme Q10, curcumin, catechins, herbs, chlorophylls, DHA, EPA, 1-methylcyclopropene, chlorine, bromine, carbon dioxide ethanol, propanol, sodium linear alkylbenzene sulfonate, alkyl glycoside, alkyl amine Examples include clathrates that include at least one of oxide, benzalkonium chloride, benzethonium chloride, dialkyl dimethyl ammonium chloride, polyoxyethylene alkyl ether acetic acid, oxalic acid, citric acid, butyric acid, and isovaleric acid.
In particular, for the freshness-keeping layer 2, a freshness-keeping film "I-SCH" (trade name) manufactured by the applicant Im Co., Ltd. can be employed as an antioxidant functional film.

(Breathable sheet layer 1)
The breathable sheet layer 1 ensures ventilation between the freshness maintaining layer 2 and the packaged object m such as food, and also facilitates sealing of the inner surfaces of this packaging material when forming this packaging material into a packaging bag. As mentioned above, the breathable sheet layer 1 is made of a resin having a lower melting point than the freshness maintaining layer 2.
It is desirable that the breathable sheet layer 1 has an oxygen permeability of 2000 cm 3 /m 2 ·24 h ·atm or more.

Since the melting point of α-cyclodextrin is 278°C, when the freshness-keeping layer 2 is made of α-cyclodextrin, the breathable sheet layer 1 is formed of a resin having a melting point lower than 278°C.
Since the melting point of β-cyclodextrin is 260°C, when the freshness-keeping layer 2 is made of β-cyclodextrin, the breathable sheet layer 1 is formed of a resin having a melting point lower than 260°C.
Since the melting point of γ-cyclodextrin is 300°C, when the freshness retaining layer 2 is made of γ-cyclodextrin, the breathable sheet layer 1 is formed of a resin having a melting point lower than 300°C.
Regarding chemically modified cyclodextrin, for example, the melting point of hydroxypropyl-β-cyclodextrin (HPβ-cyclodextrin) is 267°C. 1 is formed from a resin with a melting point lower than 267°C. For example, the melting point of methyl-β-cyclodextrin is 180 to 182°C, so if the freshness maintaining layer 2 is made of methyl-β-cyclodextrin, the breathable sheet layer 1 is formed of a resin with a melting point lower than 180°C. do.
It is important that the melting point of the resin in the sealing part is lower than the melting point of the freshness maintaining layer, that is, the various cyclodextrins mentioned above.Although the melting point of the guest molecules does not directly affect the seal, they are included in the cyclodextrin. Regarding guests, the melting point of α-lipoic acid is 60-62°C, the melting point of IPBC (3-iodo-2-propynylbutyl carbamate) is 64-68°C, the melting point of iodine is 113.6°C, and the melting point of 1-MCP is 75-76℃, the melting point of ethanol is -114.5℃.

In particular, it is desirable that the air permeable sheet layer 1 has linear low density polyethylene (LLDPE) as its main component. That is, it is suitable that the breathable sheet layer 1 is composed of an LLDPE film.
LLDPE provides sealing properties in packaging, while I-SCH utilizes the breathability of LLDPE to maintain sealing properties and achieves its own high freshness retention performance.
When a commercially available general LLDPE film is used for the breathable sheet layer 1, a film having a thickness of 30 μm or less is suitable. However, the thickness may be outside the above range as long as the above function can be ensured.
Note that a resin film other than the LLDPE film may be used as long as it provides oxygen permeability and seal strength equivalent to that of the LLDPE film.

(Low air permeability sheet layer 4)
The low air permeability sheet layer 4 preferably has an oxygen permeability of 200 cm 3 /m 2 ·24 h ·atm or less.
The low air permeability sheet layer 4 can be made of a plastic film containing aluminum. In particular, the low air permeability sheet layer 4 is desirably made of aluminum-deposited polyethylene terephthalate (VM-PET).
VM-PET can suppress deterioration of freshness due to daytime ultraviolet rays and maintain the airtightness of the packaging even when the packaging material of the present invention is displayed at a store together with the packaged items m.
However, a resin film other than VM-PET may be used as long as it has an oxygen permeability equivalent to that of VM-PET. When commercially available general VM-PET is used for the low air permeability sheet layer 4, a thickness of 12 μm or more is suitable. However, the thickness may be outside the above range as long as the low air permeability function can be ensured.

(Reinforcement sheet layer 5)
For the reinforcing sheet layer 5, it is suitable to use a nylon film. This is because nylon can maintain the strength of the bag (packaging material).
However, any resin film other than nylon film may be used as long as it can reinforce this packaging material.
When a commercially available general nylon film is used for the reinforcing sheet layer 5, a film with a thickness of 15 μm or more is suitable. However, the thickness may be outside the above range as long as the reinforcing function can be ensured.

(Laminate layer 3)
A polyethylene (PE) film can be used to form both the first laminate layer 3a and the second laminate layer 3b. However, a resin film other than PE may be used as long as it can perform appropriate lamination between the above layers. Moreover, each laminate layer 3a, 3b may be formed by coating an adhesive other than a resin film.

(Example of manufacturing method)
With reference to FIG. 2, an example of a method for manufacturing the packaging material shown in FIG. 1(A) will be described.
By coating the breathable sheet 1 (breathable sheet layer 1 before lamination) shown in FIG. 2(A) with the freshness maintaining material, a highly breathable sheet L1 with a freshness preserving function shown in FIG. 2(B) is formed. (first step).

The low air permeability sheet 4 ( low air permeability sheet layer 4 before lamination) is laminated onto the sheet L1 via the first laminate layer 3a using a commercially available known laminating machine (not shown). One sheet L2 shown in (C) is obtained (second step).
Further, using the laminating machine, the reinforcing sheet 5 (reinforcing sheet layer 5 before lamination) is laminated onto the sheet L2 via the second laminating layer 3b to form the packaging sheet L (packaging film), that is, the book shown in FIG . 2 (D). Forming the packaging material of the invention (third step).

(Seal strength)
Figure 3 shows the seal strength test results.
Sample s1 is an example in which the reinforcing sheet layer 5 is removed from the example shown in FIG. 1(C). Sample s2 is a comparative example in which the breathable sheet layer 1 is formed in the opposite direction to the freshness maintaining layer 2 from that of sample s1, and a glass sealing layer 6 is provided. Sample s3 is an example in which the reinforcing sheet 5 is removed from the examples shown in FIGS. 1(A) and 3. Sample s4 is a comparative example in which a breathable sheet layer 1 was further provided in place of the glass sealing layer 6 of sample s3. Sample s5 is an example in which the reinforcing sheet 5 is removed from the example shown in FIG. 1(B). Sample s6 is a comparative example in which the arrangement of the laminate layer 3 (adhesive layer) and freshness maintaining layer 2 of sample s4 is reversed. Sample s7 is a comparative example composed of only the freshness maintaining layer 2 and the reinforcing sheet layer 5. Sample s8 is a single reinforcement sheet 5 (comparative example). Sample s9 is a single breathable sheet 1 (comparative example).

The test data (conditions) for seal strength are as follows.
For the breathable sheet 1, LLDPE #30 L4102 (trade name) with a thickness of 30 μm manufactured by Toyobo Co., Ltd. (2-2-8 Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture) was used. As the low air permeability sheet 4, a 12 μm thick VMPET #12 Tetraite (trade name) PC manufactured by Oike Kogyo Co., Ltd. (181 Kizokuyama-cho, Nishinotoin Nishiiri, Bukkoji-dori, Shimogyo-ku, Kyoto City) was used. For the freshness maintaining layer 2, I-SCH (trade name) manufactured by Im Co., Ltd. (2304 Tsune, Doimachi, Shikokuchuo City, Ehime Prefecture) was used as the I-SCH treatment layer. As the reinforcing sheet 5, OPP#25 P5573 (trade name) manufactured by Toyobo Co., Ltd. with a thickness of 15 μm was used. For the glass sealing layer 6, a glass plate with a thickness of 0.25 mm was used.
Details of the measuring device are as follows.

A model P-200 BU manufactured by Fuji Impulse Co., Ltd. (4-23-18 Shonai Sakaemachi, Toyonaka City, Osaka Prefecture) was used as the laminating device for the sample shown in FIG. 3, and the memory was set to 6 on a 10-level scale.
The tensile compression tester shown in Figure 3 was model RTE-1210 manufactured by A&D Co., Ltd. (3-23-14 Higashiikebukuro, Toshima-ku, Tokyo).
The test method shown in FIG. 3 is based on the Japanese Industrial Standard (JIS) Z 0238: 1998 "Testing methods for heat sealed flexible packaging bags and semi-rigid containers".
For samples s1 to s7, a seal portion S shown in FIG. 4 was formed, and the above test was conducted on the seal portion S.

Looking at the test results shown in Figure 3, the seal strength of samples s1, s3, and s5, which are examples of the present invention, was all 30 N/15 mm or more, confirming that practical seal strength was secured. can. In samples s2 and s7 as comparative examples, the seal strength did not exceed 3N/15 mm, and the difference from the seal strength of the above example is obvious.
Samples s4 and s6 were used as comparative examples because although there was no problem with the sealing strength, the desired sealing effect could not be obtained.
Furthermore, when the material was LLDPE only (samples s4 and s6), there was a small amount of oxygen leaking from inside the package (inside) to outside the package (outside). Regarding the LLDPE inner surface coating (samples s2 and s4), it was confirmed that the air permeability was 80% (assuming the air permeability without the LLDPE inner surface coating to be 100%). The laminate with VM-PET had almost no external leakage (leakage of oxygen from the inside of the package to the outside) (samples s1, s3, s5). As for the coating of the freshness-maintaining material (freshness-maintaining layer 2) on the innermost side of the package, that is, the surface facing the packaged item (samples s2 and s7), the freshness-maintaining performance was high as expected, but the sealing performance was is low. The greatest effect was obtained by coating both sides of the freshness maintaining material with the laminate layer in between (sample s1).
The O2 consumption amount in FIG. 3 refers to the amount of conversion of active oxygen (ROS) into inert oxygen when the active oxygen (ROS) is sealed in a package. It can be said that the larger the conversion amount, the higher the effect of maintaining freshness. As shown in Fig. 3, in samples s1 to s7 that use I-SCH in the freshness maintenance layer 2, it can be confirmed that the O2 consumption exceeds 0.6 in all samples, and it can be expected that I-SCH will effectively maintain freshness. .

Tables 1 to 5 show test results regarding freshness maintenance. The film structure in each table is the same as samples s1, s3 to s9 shown in the sample structure of FIG. That is, in the test, the breathable sheet layer 1 was made of LLDPE #30 L4102 made by Toyobo Co., Ltd. with a thickness of 30 μm, the freshness-maintaining layer 2 was made of I-SCH made by the applicant Im Co., Ltd., and the low breathability sheet was made of Layer 4 is made of VMPET #12 Tetraite with a thickness of 12 μm from Oike Kogyo Co., Ltd., reinforcing sheet layer 5 is OPP #25 P5573 with a thickness of 15 μm from Toyobo Co., Ltd., and glass sealing layer 6 is made of OPP #25 P5573 with a thickness of 15 μm. A glass plate with a diameter of 0.25 mm was used.

Each data of samples s1, s3 to s9 in Table 1 shows the results of visual observation of discoloration (blackening) 6 days after packaging, using a banana as the packaged object (object). ◎ indicates that no blackening was observed, ○ indicates that almost no blackening was observed, △ indicates that blackening was observed in some areas, and × indicates that blackening was observed almost entirely. show.
Each of the freshness maintaining layers of samples s1, s3 to s7 in Table 1 is a clathrate in which the host is α-cyclodextrin and the guest is 1-methylcyclopropene.
As shown in Table 1, no blackening of the banana is observed in the configurations of samples s1 and s7, almost no blackening is observed in the configurations of samples s3 and s4, and partial blackening is observed in the configurations of samples s5 and s6. was observed, but it was within a non-problematic range, and blackening was observed throughout in the configurations of samples s8 and s9.

Each data of samples s1, s3 to s9 in Table 2 shows the results of visually observing and smelling the state of discoloration and odor 3 days after packaging, using beef as the packaged object (object). ◎ indicates that there was no discoloration or odor at all, ○ indicates that there was almost no discoloration or odor, △ indicates that discoloration or a slight odor occurred in some areas, × indicates that discoloration or odor occurred almost entirely. Indicates that there was
Each of the freshness maintaining layers of samples s1, s3 to s7 in Table 2 is a clathrate in which the host is γ-cyclodextrin and the guest is α-lipoic acid.
As shown in Table 2, in the configurations of samples s1 and s7, there is no discoloration or generation of off-odor in the beef, in the configurations of samples s3 and s4, there is almost no discoloration or generation of off-odor, and in the configuration of sample s5, there is only partial discoloration and odor. Although the generation of a slight odor was observed, it was within a non-problematic range, and in the configuration of sample s9, overall discoloration and generation of an odor were observed.

Each data of samples s1, s3 to s9 in Table 3 shows the results of visual observation of mold growth and discoloration 6 days after packaging, using strawberries as the packaged item (object). ◎ indicates that no mold or discoloration was observed, ○ indicates that almost no mold or discoloration was observed, △ indicates that mold or discoloration was observed in some areas, and × indicates that mold or discoloration was observed almost entirely. Indicates that the
The freshness maintaining layers of samples s1, s3 to s7 in Table 3 are clathrates in which the host is hydroxypropyl β-cyclodextrin and the guest is iodoprovinyl butyl carbamate.
As shown in Table 3, no mold or discoloration was observed in the configurations of samples s1 and s7, almost no mold or discoloration was observed in the configurations of samples s3, s4, and s6, and the configuration of sample s5 In sample s8, mold growth and discoloration were observed in some areas, but within a non-problematic range, and mold growth and discoloration were observed overall in sample s8.

The data for samples s1, s3 to s9 in Table 4 are based on the results of visually inspecting and touching the mold growth and hardness of bread 10 days after packaging. show. ◎ indicates that there was no mold growth and no hardening of the bread, ○ means that there was almost no mold growth and hardening of the bread, △ means that there was some mold growth and hardening of the bread, × means that there was some mold growth and hardening of the bread. This indicates that there was mold growth and hardening of the bread almost entirely.
The freshness maintaining layer of each of the samples s1, s3 to s7 in Table 4 is an clathrate containing α-cyclodextrin and ethanol as the guest.
As shown in Table 4, in the configuration of sample s1, there was no mold growth and no hardening of the bread, in the configurations of samples s3, s4, and s6, there was almost no mold growth and hardening of the bread, and in the configuration of sample s5, there was only partial mold growth and hardening of the bread. Although mold growth and hardening of the bread were observed, this was within a non-problematic range, and overall mold growth and hardening of the bread were observed in samples s8 and s9.

Each data of samples s1, s3 to s9 in Table 5 shows the results of visually observing and smelling the state of discoloration and odor two days after packaging, using a fish as the packaged object (object). ◎ indicates that there was no discoloration or odor at all, ○ indicates that there was almost no discoloration or odor, △ indicates that discoloration or a slight odor occurred in some areas, × indicates that discoloration or odor occurred almost entirely. Indicates that there was
Each of the freshness maintaining layers of samples s1, s3 to s7 in Table 5 is a clathrate in which the host is methyl β-cyclodextrin and the guest is an amino acid.
As shown in Table 5, in the configurations of samples s1 and s7, there is no discoloration of the fish or the generation of any strange odor, in the configurations of samples s3 and s4, there is almost no discoloration or generation of any odor, and in the configurations of samples s5 and s6, there is only partial discoloration. - Although some strange odor was observed, it was in a non-problematic range, and in the configurations of samples s8 and s9, an overall discoloration and an odor were observed.

From the results shown in Tables 1 to 5, it can be confirmed that the configurations of samples s1, s3, and s5, which are examples of the present invention, ensure seal strength and the ability to maintain freshness within a practical range. In particular, it was confirmed that samples s1 and s3, which are examples of the present invention, exhibit good sealing strength and freshness maintaining ability, and among them, sample s1 has an extremely good sealing ability for both the freshness maintaining material and the object. It can be confirmed that it exhibits the ability to maintain freshness along with clamping.
From the results of sample s1 in Tables 1 to 5 above, the configuration shown in Figure 1(B) is extremely superior in maintaining freshness and securing seal strength, and from the results of samples s3 and s5 in Tables 1 to 5, it is extremely effective in maintaining freshness and securing seal strength. It can be seen that the configuration of FIG. 1(A) is second to sample s1 in terms of security.

(Brief Summary)
As mentioned above, the sealing strength of the freshness-preserving layers using cyclodextrin (CD) is significantly reduced due to the high melting point of CD (FIG. 4(C)). Therefore, in the present invention, a film with air permeability (oxygen permeability) is used as a sealing surface (FIGS. 4(A) and 4(B)), and a CD (freshness retaining layer) is placed on the non-sealing surface (non-sealing area described later). ) was created to maintain the sealing strength of the material.

That is, the present invention provides a packaging material for packaging an object to be packaged such as food, which comprises at least a main packaging material for packaging the object to be packaged, and a surface of the main packaging material that faces the object to be packaged. and a breathable layer (breathable sheet layer 1) having air permeability provided on the surface of the freshness maintaining layer 2 facing the packaged item m, and the main packaging material includes one or more air permeable layers. It is composed of a plurality of low air permeability layers (low air permeability sheet layer 4), and the low air permeability layer or other layers constituting the main packaging material are formed of the first resin, and the above-mentioned The air permeable layer has higher air permeability than the low air permeability layer, the freshness maintaining layer 2 has a cyclic oligosaccharide (CD), and the air permeability layer is made of a second resin. The second resin is a packaging material that is a resin that can make the heat fusion between the second resins stronger compared to the case where the freshness maintaining layers 2 are heat fused together. provide.

(Example of change)
In the present invention, the above-mentioned packaging materials include not only those that wrap the packaged object m such as a packaging bag as described above, but also those that place the packaged object m on top without wrapping it, those that sandwich it between, and those that are laid underneath. It can also be used as a stand-alone sheet.
When processing the packaging material according to the present invention into a packaging bag, it is possible to use heat sealing (heat sealing method) in which the resin in the area to be sealed is melted and bonded with heat using a bag making machine.
When using the above-mentioned heat seal (heat seal method), either the well-known heat press seal method or side seal (fusion seal) method may be used.
When using a side-seal (fusion-cut seal) type bag making machine, the film melts, and the area to be sealed is instantly melted and bonded. Three-sided stickers, stand packs, zipper bags, etc. use laminate films, and by using resin for the inner film layer of the bag that has a lower melting (melting and bonding) temperature than the outside, strong adhesion is achieved. It is possible.

In the example of FIG. 1(A), the first laminate layer 3a is placed between the freshness maintaining layer 2 and the low air permeability sheet layer 4, but as shown in FIG. 1(B), the air permeable sheet layer 1 and the freshness maintaining A first laminate layer 3a may be formed between the layer 2 and the layer 2.
Further, as shown in FIG. 1(C), the freshness maintaining layer 2 is a first freshness maintaining layer 2a, and the first laminate layer 3a and the low air permeability sheet layer 4 are formed separately from the first freshness maintaining layer 2a. It can also be implemented as having a second freshness maintaining layer 2b containing a cyclic oligosaccharide therebetween.
In this case, the low air permeability sheet layer 4 is particularly preferably a VM-PET film.
The second freshness-maintaining layer 2b and the first freshness-maintaining layer 2a in FIG. 1(C) are both mainly composed of one of the above-mentioned compositions containing cyclobuxtrin, similar to the freshness-maintaining layer 2 in FIG. 1(A). shall be.

In addition, as shown in FIG. 1(D), the above-mentioned breathable sheet layer 1 located at the innermost side of the package was defined as the first breathable sheet layer 1a, and in FIG. 1(C), the above-mentioned low breathable sheet layer 4 was defined. Instead of the VM-PET film, an LLDPE film may be disposed at the position of the VM-PET film as the second breathable sheet layer 1b. In the case of FIG. 1(D), the nylon film that is the reinforcing sheet layer 5 also serves as the low air permeability sheet layer 4.
In the example shown in FIG. 1(C) and FIG. 1(D), the freshness maintaining layer 2 is the first freshness maintaining layer 2a, and the packaging material has the first freshness maintaining layer 2a and the first freshness maintaining layer 2a. Although the second freshness maintaining layer 2b is separate from the layer 2a, the freshness maintaining layer 2 has a first freshness maintaining layer 2a, a first laminate layer 3a, and a second freshness maintaining layer 2b. It may be considered as one layer composed of layer 2b.
Matters not specifically mentioned in the examples of FIGS. 1(B) to (D) are the same as those of the embodiment shown in FIG. 1(A).

In addition to the embodiments described above, as shown in FIG. 4(B), the packaging material includes, in order from the inside of the package, the freshness maintaining layer 2, the air permeable sheet layer 1, and the low air permeable sheet layer. 4, at least three layers. The breathable sheet layer 1 has a non-sealed area (inner area other than the sealed part S) covered with the freshness-maintaining layer 2 (facing the freshness-maintaining layer 2), and a non-sealed area (inner area other than the sealed part S) covered with the freshness-maintaining layer 2 (facing the freshness-maintaining layer 2), (not facing layer 2) sealing area (area that becomes sealing portion S). Similar to the embodiments described above, the air permeable sheet layer 1 can be a resin layer that has higher air permeability than the low air permeability sheet layer 4 and has a lower melting point than the freshness maintaining layer 2. Even if formed in this way, it is possible to achieve both the objective of the present application of ensuring air permeability between the freshness maintaining layer 2 and the packaged object and improving the sealing strength.

In particular, in the example shown in FIG. 4(B), the freshness maintaining layer 2 is placed at a position where it directly touches the food (packaged object m) without passing through the breathable sheet layer 1, so the freshness maintaining efficiency is extremely high. Furthermore, although the breathable sheet layer 1 is disposed inside the freshness-maintaining layer 2 and does not cover the freshness-maintaining layer 2 against food, it does not impede the above-mentioned sealing performance.
The packaging material according to the present invention is not limited to food packaging materials for packaging foods. In addition to food, the packaging material according to the present invention may contain medicines and metals, and may also contain odour-emitting filth and waste.

1 Breathable sheet layer 2 Freshness maintaining layer 2a First freshness maintaining layer 2b Second freshness maintaining layer 3a Laminate layer (first laminate layer)
3b Laminate layer (second laminate layer)
4 Low air permeability sheet layer 5 Reinforcement sheet layer L Packing sheet (packaging material)
L1 (highly breathable) sheet L2 sheet

Claims (11)

The package consists of, in order from the inside, a breathable sheet layer, a freshness maintaining layer, and a low breathability sheet layer.
Only one layer of the breathable sheet layer is provided in the packaging material as a layer directly facing the packaged object,
The freshness maintaining layer contains a cyclic oligosaccharide,
The freshness-maintaining layer includes a freshness-maintaining material that maintains the freshness of fresh produce such as fruits and vegetables by suppressing deterioration of the food, and contains the cyclic oligosaccharide, that is, cyclodextrin, as a composition of the freshness-maintaining material. and
The cyclodextrin is a clathrate containing a guest molecule, and the cyclodextrin includes α cyclodextrin, β cyclodextrin, γ cyclodextrin, branched β cyclodextrin, methylated α cyclodextrin, and methylated β cyclodextrin. Dextrin, methylated gamma cyclodextrin, hydroxypropyl alpha cyclodextrin, hydroxypropyl beta cyclodextrin, hydroxypropyl gamma cyclodextrin, monochlorotriazino alpha cyclodextrin, monochloro triazino beta cyclodextrin, monochloro triazino gamma cyclodextrin, triacetyl alpha at least one of cyclodextrin, triacetyl β cyclodextrin, and triacetyl γ cyclodextrin,
The cyclodextrin may include alpha lipoic acid, metal, metal salt, metal oxide, biguanide, carbanilide, surfactant, carboxylic acid, alcohol, ammonium salt, phenol derivative, amino acid, iodine compound, coenzyme Q10, curcumin, catechins, Herbs, chlorophylls, DHA, EPA, 1-methylcyclopropene, chlorine, bromine, carbon dioxide ethanol, propanol, sodium linear alkylbenzene sulfonate, alkyl glycoside, alkyl amine oxide, benzalkonium chloride, benzethonium chloride, dialkyl chloride The clathrate includes at least one of dimethyl ammonium, polyoxyethylene alkyl ether acetic acid, oxalic acid, citric acid, butyric acid, and isovaleric acid,
The air permeable sheet layer is a resin layer that has higher air permeability than the low air permeability sheet layer and has a lower melting point than the freshness maintaining layer,
The breathable sheet layer is a layer mainly composed of linear low density polyethylene,
The oxygen permeability of the breathable sheet layer is 2000 cm / m / 24 h / atm or more,
The oxygen permeability of the low air permeability sheet layer is 200 cm / m / 24 h / atm or less,
The freshness maintaining layer is coated on the surface of the breathable sheet layer opposite to the surface facing the packaged object with a coating liquid containing an aqueous cyclodextrin solution, monohydric alcohol, and a binder resin. A packaging material characterized by a layer of 2. The packaging material according to claim 1, wherein the low air permeability sheet layer is laminated to the surface of the freshness fiber layer opposite to the air permeability sheet layer via a polyethylene laminate layer. The freshness-maintaining layer is a first freshness-maintaining layer, and a second freshness-maintaining layer is provided between the laminate layer and the low air permeability sheet layer separately from the first freshness-maintaining layer,
The packaging material according to claim 2, wherein the second freshness maintaining layer contains a cyclic oligosaccharide. 2. The packaging material according to claim 1, wherein the low air permeability sheet layer is made of a plastic film containing aluminum. 2. The packaging material according to claim 1, wherein the freshness maintaining material is a clathrate in which the host is α-cyclodextrin and the guest is 1-methylcyclopropene or ethanol. 2. The packaging material according to claim 1, wherein the freshness maintaining material is a clathrate in which the host is γ-cyclodextrin and the guest is α-lipoic acid. 2. The packaging material according to claim 1, wherein the freshness maintaining material is a clathrate in which the host is hydroxypropyl β-cyclodextrin and the guest is iodoprovinyl butyl carbamate. 2. The packaging material according to claim 1, wherein the freshness maintaining material is a clathrate in which the host is methyl β-cyclodextrin and the guest is an amino acid. A reinforcing sheet layer is provided on the opposite side of the freshness maintaining layer of the low air permeability sheet layer,
A laminated film in which a laminate layer is interposed between the freshness maintaining layer and the low air permeability sheet layer and between the low air permeability sheet layer and the reinforcing sheet layer, respectively. Packaging material according to item 1. A first step of forming the breathable sheet layer and the freshness maintaining layer by coating the freshness maintaining material on a breathable sheet;
a second step of forming the low air permeability sheet layer by laminating the low air permeability sheet to the freshness maintaining layer via a laminate material that is one of the laminate layers;
The package according to claim 9 , further comprising a third step of forming the reinforcing sheet layer by laminating a reinforcing sheet to the low air permeability sheet layer via a laminate material that is another one of the laminate layers. Method of manufacturing materials. A bag-shaped packaging material that includes a sealed area and a non-sealed area that are not sealed in the breathable sheet layer, and that is sealed in the sealed area,
The freshness maintaining layer is a layer of substantially uniform thickness that faces at least the entire non-sealed area without interruption,
2. The packaging material according to claim 1, wherein the breathable sheet layer has a substantially uniform thickness over at least the entire non-sealed area.

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