JP2017024762A - Paper container for packed food - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper container for packed food excellent in separability from food, in which peel-off of an innermost layer can be prevented in a manufacturing process and there is no risk of content fluid leaking.SOLUTION: A paper container for packed food is formed of a container material including, from an outer surface side to an inner surface side: a thermoplastic resin layer (layer A) whose main component is polyethylene resin; a paper base material layer (layer B); a thermoplastic resin layer (layer C) whose main component is polyethylene resin; a barrier layer (layer D); an adhesion layer (layer E) whose main component is ethylene-methacrylic acid copolymer resin; a thermoplastic resin layer (layer F) whose main component is polyethylene resin; a thermoplastic resin layer (layer G) which is a mixture of polyethylene resin and polypropylene resin; and a thermoplastic resin layer (layer H) which is formed by adding a compounding agent selected from polyolefin-based resin, polyatomic alcohol or its derivative, and a polyoxyethylene derivative to polyethylene resin.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a filled food paper container used for producing a food in a container in which a food material such as tofu is filled in a container and sealed and heated and solidified.

There are foods (hereinafter referred to as “filled foods”) that are manufactured by filling a container with such materials as tofu, water yokan, pudding, etc., and sealing and heating to solidify.
For example, when the filled food is tofu, the container is filled with tofu material filled with soy milk and a coagulant and sealed, and the container filled with the tofu material is heated at 60 to 100 degrees to produce filled tofu. (For example, refer to Patent Document 1).

Metal containers, synthetic resin containers, paper containers, etc. are known as containers used for filled foods such as filled tofu, but paper containers have become widespread due to ease of disposal after use and recycling characteristics. ing. As a paper container for hermetically containing food, from the outer surface side toward the inner surface side, a thermoplastic resin layer mainly composed of polyethylene resin, a paper base layer, a thermoplastic resin layer mainly composed of polyethylene resin, and a barrier layer As a result, there is a paper container formed of a paper container material having a thermoplastic resin layer mainly composed of a polyethylene resin in the innermost layer (see, for example, Patent Document 2).
However, when a paper container formed of a paper container material described in Patent Document 2 is used as a container for filled food, a thermoplastic resin mainly composed of a food solidified in the container and a polyethylene resin that becomes the inner surface of the container The separation from the layer was poor, and when the food was taken out, the food adhered to the inner surface, and it was difficult to take out or some of the food could be missing.

A polyolefin-based resin composition in which a compounding agent selected from a polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative is added to a polyolefin-based resin is used to improve the releasability between the inner surface of the container and the food solidified in the container. It has been proposed (see, for example, Patent Document 3).
If the technique described in Patent Document 3 is applied to the innermost layer of the paper container material described in Patent Document 2, the separation between the inner surface of the paper container and the food is improved, and the food can be easily removed from the paper container. Can be taken out.

As an example of applying the technique described in Patent Document 3 to the innermost layer of the paper container material described in Patent Document 2, a thermoplastic resin mainly composed of polyethylene resin constituting the innermost layer of the paper container material described above It is considered that a polyethylene resin film to which a compounding agent selected from polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative is added is laminated on the layer to form an innermost layer.
However, when a paper container formed of the paper container material obtained in this way is used as a container for filled food, the polyethylene resin layer as the innermost layer to which the compounding agent is added, and the polyethylene resin inside thereof as the main component In some cases, peeling occurs between the thermoplastic resin layer and the content liquid leaks.

JP 2014-187975 A JP 2004-17984 A JP-A-7-62163

  The peeling that occurs between the polyethylene resin layer, which is the innermost layer to which the above-mentioned compounding agents are added, and the thermoplastic resin layer, the main component of which is polyethylene resin, fills the container with food material and seals it. When it is heated, the compounding agent added to the innermost polyethylene resin layer elutes and may be caused by the transition to the thermoplastic resin layer mainly composed of the inner polyethylene resin. all right.

  The present inventors made filling so that the compounding agent eluted from the polyethylene resin layer as the innermost layer to which the compounding agent was added did not move between the thermoplastic resin layer mainly composed of the polyethylene resin inside. As a result of repeated research to obtain a paper container for food, a polyethylene resin and a polypropylene resin were placed between a polyethylene resin layer to which a compounding agent was added and a thermoplastic resin layer mainly composed of a polyethylene resin inside. By interposing the mixed thermoplastic resin layer, the compounding agent eluted from the polyethylene resin layer added with the compounding agent was found not to move between the thermoplastic resin layer mainly composed of the polyethylene resin inside. The present invention has been completed.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a filled food paper container that has good releasability from food and that prevents the innermost layer from peeling off during the manufacturing process and that does not cause leakage of liquid contents.

  In order to achieve the above object, a filled food paper container according to the invention described in claim 1 comprises a thermoplastic resin layer (A layer) comprising a polyethylene resin as a main component from the outer surface side to the inner surface side, a paper base material. Layer (B layer), thermoplastic resin layer (C layer) mainly composed of polyethylene resin, barrier layer (D layer), adhesive layer (E layer) mainly composed of ethylene / methacrylic acid copolymer resin, polyethylene Thermoplastic resin layer (F layer) mainly composed of resin, thermoplastic resin layer (G layer) in which polyethylene resin and polypropylene resin are mixed, polyethylene resin and polyolefin resin, polyhydric alcohol or its derivative, and polyoxyethylene derivative It consists of container materials provided with the thermoplastic resin layer (H layer) which added the compounding agent chosen from these.

  The filled food paper container according to the invention described in claim 2 has a mixing ratio of the polyethylene resin and the polypropylene resin constituting the thermoplastic resin layer (G layer) of claim 1 of 3: 7 to 4: 6. It is characterized by being.

  The filled food paper container according to the invention described in claim 3 is a linear low density polyethylene resin constituting the thermoplastic resin layer (H layer) according to any one of claims 1 and 2. It is a polyethylene resin.

According to the filled food paper container of claim 1, the innermost layer of the paper container material is a thermoplastic resin in which a polyethylene resin is added to a polyolefin resin and a compounding agent selected from a polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative is added to a polyolefin resin. Since the layer (H layer) is used, the separation between the inner surface of the paper container and the food is improved, and the food can be easily taken out from the paper container.
In addition, a thermoplastic resin layer (G layer) in which a polyethylene resin and a polypropylene resin are mixed is provided between the thermoplastic resin layer (F layer) whose main component is a polyethylene resin inside the thermoplastic resin layer (H layer). Since it has an intervening laminated structure, the ingredients from the thermoplastic resin layer (H layer), which is the innermost layer, in the process of filling the container with food materials such as tofu, sealing and solidifying by heating Elution is suppressed by the thermoplastic resin layer (G layer), and the transition to the thermoplastic resin layer (F layer) can be prevented, whereby the heat from the thermoplastic resin layer (F layer) can be prevented. Since the occurrence of peeling of the plastic resin layer (H layer) can be prevented, a filled food paper container free from leakage of the content liquid can be obtained.

  According to the filled food paper container of claim 2, the mixing ratio of the polyethylene resin and the polypropylene resin constituting the thermoplastic resin layer (G layer) of claim 1 is from 3: 7 to 4: 6. Therefore, the elution of the compounding agent from the thermoplastic resin layer (H layer) which is the innermost layer can be more effectively suppressed, and the thermoplastic resin layer (H from the thermoplastic resin layer (F layer) can be suppressed. Occurrence of peeling of the layer) can be more effectively prevented.

  According to the filled food paper container of claim 3, the polyethylene resin constituting the thermoplastic resin layer (H layer) according to any one of claims 1 or 2 is a linear low density polyethylene. Since the resin is used, strong adhesive strength, heat resistance, and pinhole resistance can be obtained.

It is explanatory drawing which shows an example of the laminated structure of the container material which forms the filling food paper container which concerns on this invention.

Hereinafter, an example of an embodiment of a filled food paper container according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is an explanatory view showing an example of a laminated structure of container materials forming a filled food paper container according to the present invention.
The filled food paper container of this example has a thermoplastic resin layer (A layer) mainly composed of polyethylene resin, a paper base layer (B layer), and a thermoplastic material mainly composed of polyethylene resin, from the outer surface side to the inner surface side. A resin layer (C layer), a barrier layer (D layer), an adhesive layer (E layer) containing ethylene / methacrylic acid copolymer resin as a main component, a thermoplastic resin layer (F layer) containing polyethylene resin as a main component, A thermoplastic resin layer (G layer) obtained by mixing polyethylene resin and polypropylene resin, and a thermoplastic resin layer (H layer) obtained by adding a compounding agent selected from a polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative to a polyolefin resin to a polyethylene resin. ).

Of the above laminated structure, a thermoplastic resin layer (A layer) mainly composed of a polyethylene resin, a paper base layer (B layer), a thermoplastic resin layer (C layer) mainly composed of a polyethylene resin, and a barrier layer. (D layer), adhesive layer (E layer) containing ethylene / methacrylic acid copolymer resin as the main component, and thermoplastic resin layer (F layer) containing polyethylene resin as the main component. There is no difference from the container material used as a container.
In this example, the thermoplastic resin layer (C layer) has a linear low density polyethylene resin (LLDPE) as a component, and the thermoplastic resin layer (F layer) has a high pressure method low density polyethylene resin (LDPE) as a component. . Moreover, the aluminum foil is used as a barrier layer (D layer).

The container material forming the filled food paper container according to the present invention has a thermoplastic resin layer (G layer) on the outside (inner side of the container) of the thermoplastic resin layer (F layer) of the laminated structure laminated as described above. ), A thermoplastic resin layer (H layer) is laminated.
The thermoplastic resin layer (G layer) laminated on the outer side of the thermoplastic resin layer (F layer) contains a thermoplastic resin in which a polyethylene resin and a polypropylene resin are mixed as a component.
The mixing ratio of polyethylene resin: polypropylene resin is preferably 3: 7 to 4: 6. When the ratio of the polyethylene resin is 4 or more, the suppression of the compounding agent eluted from the thermoplastic resin layer (H layer) described later is lowered, and when the ratio of the polyethylene resin is 3 or less, the adhesiveness is lowered.

  The thermoplastic resin layer (H layer) constitutes the innermost layer (inner surface of the container). In this example, a linear low density polyethylene resin (LLDPE) is used as a component, and the polyethylene resin is a polyolefin resin. A compounding agent selected from polyhydric alcohols or derivatives thereof and polyoxyethylene derivatives is added. The addition amount of the compounding agent is 5 to 20%, preferably 10%. If the addition amount of the compounding agent is less than 5%, the inner surface of the paper container, that is, the separation property between the thermoplastic resin layer (H layer) and the food is deteriorated, and if it exceeds 20%, the thermoplastic resin layer (H The adhesiveness of the layer) decreases.

According to the filled food paper container formed of the container material having the laminated structure configured as described above, the innermost layer of the paper container material which becomes the inner surface of the paper container is made of polyethylene resin and polyolefin resin to polyhydric alcohol or Because it is a thermoplastic resin layer (H layer) to which a compounding agent selected from the derivatives and polyoxyethylene derivatives is added, the inner surface of the paper container and the food are easily separated, and the food can be easily taken out from the paper container. .
In addition, a thermoplastic resin layer (G layer) in which polyethylene resin and polypropylene resin are mixed is interposed between the thermoplastic resin layer (F layer) containing polyethylene resin as a main component inside the thermoplastic resin layer (H layer). Because of the laminated structure, the ingredients are eluted from the innermost thermoplastic resin layer (H layer) in the process of filling the container with food materials such as tofu, sealing, and solidifying by heating. Is suppressed by the thermoplastic resin layer (G layer), and the transition to the thermoplastic resin layer (F layer) can be prevented, and the thermoplastic resin layer (H layer) from the thermoplastic resin layer (F layer) can be prevented. The occurrence of peeling can be prevented.

Hereinafter, examples of the filled food paper container according to the present invention and comparative examples will be given, and the test results of peelability and detachability will be described.
<Example>
Example 1
From the outer surface side to the inner surface side, a thermoplastic resin layer (A layer) composed mainly of polyethylene resin, a paper base material layer (B layer), and a thermoplastic resin composed mainly of linear low density polyethylene resin (LLDPE) Layer (C layer), barrier layer (D layer), adhesive layer (E layer) mainly composed of ethylene / methacrylic acid copolymer resin, thermoplastic resin mainly composed of high pressure method low density polyethylene resin (LDPE) Layer (F layer), thermoplastic resin layer (G layer) in which polyethylene resin and polypropylene resin are mixed at a ratio of 4: 6, selected from polyethylene resin and polyolefin resin, polyhydric alcohol or derivative thereof, and polyoxyethylene derivative A paper container was formed of a container material provided with a thermoplastic resin layer (H layer) containing as a component a high-pressure low-density polyethylene resin (LDPE) to which 5% of a compounding agent was added.
Example 2
A polyethylene container and a polypropylene resin in the thermoplastic resin layer (G layer) of Example 1 are mixed at a ratio of 3: 7, and other than that, a paper container is formed with a container material having the same thermoplastic resin layer as Example 1. did.
Example 3
20% is added to the polyethylene resin of the thermoplastic resin layer (H layer) of Example 1 as a compounding agent selected from a polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative to a polyolefin resin. A paper container was formed using a container material having the same thermoplastic resin layer as that of No. 1.
<Comparative example>
Comparative Example 1
The thermoplastic resin layer composed of the same laminated structure as in Example 1 and corresponding to the G layer in Example 1 is a thermoplastic resin layer in which the polyethylene resin and the polypropylene resin are mixed at a ratio exceeding 4 in the mixing ratio of the polyethylene resin and the polypropylene resin. A paper container was formed from the other thermoplastic resin layers using a container material having the same thermoplastic resin layer as in Example 1.
Comparative Example 2
The thermoplastic resin layer composed of the same laminated structure as in Example 1 and corresponding to the G layer in Example 1 is a thermoplastic resin layer in which polyethylene resin and polypropylene resin are mixed at a ratio of less than 3 in the mixing ratio of polyethylene resin and polypropylene resin. A paper container was formed from the other thermoplastic resin layers using a container material having the same thermoplastic resin layer as in Example 1.
Comparative Example 3
A thermoplastic resin layer composed of the same laminated structure as in Example 1 and corresponding to the thermoplastic resin layer (H layer) in Example 1 is formed by using a polyethylene resin, a polyolefin resin, a polyhydric alcohol or a derivative thereof, and a polyoxyethylene derivative. A paper container was formed of a container material having the same thermoplastic resin layer as in Example 1 except that a thermoplastic resin layer added by 4% was added as an additive amount selected from the following.

<Test items, test methods and test results>
The paper containers shown in the above-mentioned Examples 1, 2, 3 and Comparative Examples 1, 2, 3 are filled with soy milk and bittern as a material such as tofu with a filling machine, sealed and heated at 90 degrees for 30 minutes. Manufacturing.
Thus, the filling tofu manufactured using the paper container shown in the said Example 1, 2, 3 and the comparative examples 1, 2, and 3 as a sample 1 as a sample 2 for 35 days as a sample 2 and 35 as a sample 2 The sample is stored for 13 days in an environment of 5 degrees, as a sample 3, for 5 days in an environment of 55 degrees, and as a sample 4, for 12 days in an environment of 55 degrees.
[Peelability test]
○ Test method (A) After the storage period has elapsed, take out the tofu from samples 1, 2, 3, and 4, open the container material, and visually check the innermost layer from the thermoplastic resin layer (F layer). Separation of the resin layer (G layer) and the thermoplastic resin layer (H layer) was confirmed.
(B) Samples 1, 2, 3, and 4 from which tofu was taken out were cut into strips in the flow direction, immersed in acetic acid, and the immersed portion was subjected to rubbing and stretching force to forcibly thermoplastic resin. The peeling of the innermost layer from the layer (F layer) was promoted.
〇 Test results According to test method (A);
No peeling of the innermost layer from the thermoplastic resin layer (F layer) was confirmed from any of Samples 1, 2, 3, and 4 in Examples 1, 2, and 3.
Although peeling of the innermost layer from the thermoplastic resin layer (F layer) was confirmed from any of Samples 1, 2, 3, and 4 in Comparative Examples 1 and 2, from Comparative Example 3, the thermoplastic resin layer (F No peeling of the innermost layer from the layer) was confirmed.
According to test method (B);
In each of Samples 1, 2, 3, and 4 in Examples 1, 2, and 3, the innermost layer did not peel from the thermoplastic resin layer (F layer).
In each of Samples 1, 2, 3, and 4 in Comparative Examples 1 and 2, the innermost layer was peeled off from the thermoplastic resin layer (F layer). From Comparative Example 3, the innermost layer was peeled off from the thermoplastic resin layer (F layer). Did not peel.
[Leaveability test]
〇 Test method After the storage period has elapsed, samples 1, 2, 3, and 4 are opened, and the tofu is taken out of the container by inversion, and confirmation of separation from the inner surface of the paper container, that is, the thermoplastic resin layer (H layer). Went.
O Test result In each of Samples 1, 2, 3, and 4 in Examples 1, 2, and 3, the separation between the tofu and the inner surface of the paper container was good.
All of Samples 1, 2, 3, and 4 in Comparative Examples 1 and 2 had good separation between tofu and the inner surface of the paper container, but any of Samples 1, 2, 3, and 4 in Comparative Example 3 However, the separation between the tofu and the inner surface of the paper container was poor.

Claims (3)

  From the outer surface side to the inner surface side, a thermoplastic resin layer (A layer) composed mainly of polyethylene resin, a paper base layer (B layer), a thermoplastic resin layer (C layer) composed mainly of polyethylene resin, and a barrier layer (D layer), adhesive layer (E layer) mainly composed of ethylene / methacrylic acid copolymer resin, thermoplastic resin layer (F layer) mainly composed of polyethylene resin, heat in which polyethylene resin and polypropylene resin are mixed It consists of a container material provided with a thermoplastic resin layer (H layer) in which a plastic resin layer (G layer), a polyolefin resin and a compounding agent selected from a polyhydric alcohol or a derivative thereof and a polyoxyethylene derivative are added to a polyethylene resin. Filled food paper container characterized by.   The filled food paper container according to claim 1, wherein a mixing ratio of the polyethylene resin and the polypropylene resin constituting the thermoplastic resin layer (G layer) is from 3: 7 to 4: 6.   The filled food paper container according to any one of claims 1 and 2, wherein the polyethylene resin constituting the thermoplastic resin layer (H layer) is a linear low-density polyethylene resin.

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