JPH08244169A - Low-odor packaging material manufacturing method - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a method for efficiently producing an inexpensive packaging material free from the oxidative odor of polyethylene. An anchor coating agent layer (2) is provided on a support material layer (1).
And a polyolefin layer 3 and a barrier layer 4 made of an aluminum foil are laminated, and then the anchor coat agent layer 5 on the aluminum foil 4 and a dry weight of 0.1 to 2.0 g /
The polyolefin-based sealant layer 6 of m ² is directly laminated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a low odor packaging material, and more particularly to a method for producing an inexpensive low odor packaging material suitable as a packaging material for foods or the like that do not like odor.

[0002]

2. Description of the Related Art Tea,
BACKGROUND ART A packaging material called an aluminum pouch has been conventionally used for packaging foods or the like that do not like the smell of grilled seaweed. For example, as shown in FIG. 2, this packaging material includes a support material 1, a first anchor coat layer 2, a polyethylene layer 3, an aluminum foil layer 4, a second anchor coat layer 5, and a sealant layer 6. The sealant layer 6 has a two-layer structure of a first polyethylene layer 61 and a second polyethylene layer 62. The first polyethylene layer 61 of the sealant layer 6 is coated on the surface of the second anchor coat layer 5 at a normal processing temperature, and then the second polyethylene layer 62 is formed on the laminated surface of the polyethylene layer 61 by low-temperature extrusion. Is formed. This is because the lamination temperature of the first polyethylene layer 61 is relatively high, so that an odor peculiar to polyethylene is generated. In order to prevent this, it is necessary to form the second polyethylene layer 62.

However, this low odor packaging material is expensive because it requires a large number of steps because the sealant layer is formed of two coats. Furthermore, the low-odor packaging material has a problem that the sealant layer cannot be thinned (for example, about 30 μm or less), and therefore the resin cost is high.

In such a low odor packaging material, as the anchor coating agent for forming the second anchor coating layer 5, a resin type anchor coating agent such as polyethyleneimine, polyurethane or polyester, or a titanate type anchor coating agent. General-purpose agents such as agents are used.

Therefore, it is an object of the present invention to provide a method for efficiently producing an inexpensive packaging material free from the oxidative odor of polyethylene.

[0006]

As a result of earnest research in view of the above object, the present inventor has used a polyolefin-based anchor coating agent to be applied to an aluminum foil layer and directly laminated a polyolefin sealant layer. It was discovered that a good low-odor packaging material can be obtained, and the present invention was conceived.

That is, in the method for producing a low-odor packaging material of the present invention, an anchor coating agent layer is formed on a barrier layer made of aluminum foil, and then 0.1 to 2.0 g / m ² in dry weight is formed on the anchor coating agent layer. The above-mentioned polyolefin sealant layer is directly laminated.

[0008]

According to the present invention, the aluminum foil layer and the polyolefin sealant layer are directly laminated with the polyolefin anchor coat layer. Since a polyolefin-based anchor coating agent is used as the anchor coat layer and a polyolefin resin is used as the sealant layer, the compatibility of both layers is good. For this reason, even if the extrusion temperature of the polyolefin forming the sealant layer is lowered, the adhesiveness is improved.

Based on such properties, in the present invention, the polyolefin is extrusion coated at a melting temperature of 300 ° C. or less to form a sealant layer. Therefore, the polyolefin forming the sealant layer is not oxidized,
Low odor is achieved. Also, since the sealant layer is a single layer, it is possible to reduce the number of steps when manufacturing a low-odor packaging material, and further it is possible to thin the sealant layer,
Resin costs can also be reduced.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

[1] Configuration of Low Odor Packaging Material FIG. 1 is a sectional view showing the configuration of the low odor packaging material according to one embodiment of the present invention. The low odor packaging material of the present invention comprises an aluminum foil layer 4, a second anchor coat layer 5, and a sealant layer 6.
Is an indispensable constituent element, and has a support material 1, a first anchor coat layer 2, and a polyolefin layer 3 as required.

(1) Aluminum Foil Layer For the aluminum foil layer 4, a general-purpose soft aluminum foil can be used. 6 ~ 15μ for aluminum foil
If the thickness is about m, and the thickness is less than 6 μm, the gas barrier property and strength are insufficient, and it is meaningless if the thickness exceeds 15 μm.

(2) Second Anchor Coat Layer In the present invention, the anchor coat agent for forming the second anchor coat layer 5 is for improving the adhesiveness with the sealant layer 6 formed by low temperature extrusion. A polyolefin-based anchor coating agent is used for the above. In particular, when the polyolefin contained in the anchor coating agent and the polyolefin forming the sealant layer 6 are of the same type, particularly polyethylene, as described later, the adhesiveness of the sealant layer 6 can be further improved. As such a polyolefin-based anchor coating agent, use of an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, or a maleic anhydride copolymer thereof, a graft product or the like. You can

The dry coating weight of the polyolefin-based anchor coating agent is 0.1 to 2.0 g / m ² , and when the coating weight of the anchor coating agent is less than 0.1 g / m ² , the aluminum foil layer 4 and the sealant layer 6 are coated. There is not enough power to bond and
Further, even if it exceeds 2.0 g / m ² , it is meaningless because the adhesive strength corresponding to it cannot be obtained.

(3) Sealant Layer Polyolefin is used for the sealant layer 6, but in the present invention, low density polyethylene or linear low density polyethylene is particularly preferably used. The sealant layer 6 is
The polyolefin is extrusion coated at a melt extrusion temperature of 300 ° C or lower, preferably at a melt extrusion temperature of 270 to 290 ° C. The melt extrusion temperature of polyolefin is
If the temperature exceeds 300 ° C, the polyolefin will start to oxidize and cause odor.

The thickness of the sealant layer 6 is 15 to 60 μm. If the layer thickness is less than 15 μm, the sealing effect of the sealant layer is not sufficient, and if it exceeds 60 μm, further improvement of the sealing effect cannot be obtained. Particularly, in the present invention, the conventional 2
It is possible to make the sealant layer thinner (about 30 μm or less), which was not possible with the layer-coated sealant layer.

(4) Support The support 1 that can be used in the present invention is not particularly limited in its material, and can be variously selected depending on the use of packaging. For example, biaxially stretched polyester, biaxially stretched polyester. In addition to films such as polyamide and biaxially oriented polypropylene, cellophane, papers and the like can be used. The thickness of the support material 1 can be variously changed depending on the use of packaging, but generally about 10 to 100 μm is sufficient.

(5) First Anchor Coat Layer When the first anchor coat layer 2 is provided, the anchor coat agent is a resin-based anchor coat agent such as polyethyleneimine, polyester, or polyurethane, or a titanate-based anchor coat agent. A general purpose one such as can be used. The amount of anchor coating agent applied is dry weight.
Preferably 0.1 ~2.0 g / m ^2, the coating amount of the anchor coating agent is insufficient adhesive strength between the support member 1 and the polyethylene layer 2 is less than 0.1 g / m ^2, also exceed 2.0 g / m ² However, it is not economical because the adhesive strength cannot be further improved.

(6) Polyolefin Layer For the polyolefin layer 3, it is preferable to use polyethylene, particularly low density polyethylene or linear low density polyethylene, as in the sealant layer 6, and particularly low melt index (MI) of 2-10. Density polyethylene or linear low density polyethylene is preferred. The thickness of the polyolefin layer 3 is
10 to 30 μm is preferable, and if it is less than 10 μm, film formation during extrusion coating is difficult, and 30 μm
There is no point in exceeding.

[2] Manufacturing Method of Low Odor Packaging Material As an example of the low odor packaging material, a manufacturing method of the configuration shown in FIG. 1 will be described. First, an anchor coating agent is applied to the support material 1 to form a first anchor coat layer 2, and then this and the aluminum foil layer 4 are extrusion laminated with polyethylene to form the support material 1 and the anchor coat layer. 2 and a polyolefin (polyethylene) layer 3,
A laminated body including the aluminum foil layer 4 is formed.

Next, an olefinic anchor coat agent is applied to the surface of the aluminum foil layer 4 of the laminate thus formed to form the second anchor coat layer 5. Then, a polyolefin such as polyethylene is extrusion coated thereon under the above-mentioned conditions. In the present invention, since the anchor coat agent of the second anchor coat layer 5 for adhering the sealant layer 6 and the aluminum foil layer 4 is a polyolefin type, even if the extrusion coating is performed at a melting temperature of 300 ° C. or less, the sealant is used. The layer 6 and the aluminum foil layer 4 adhere well.

In the above, it is essential to form the second anchor coat layer 5 on the surface of the aluminum foil layer 4 and then directly laminate the sealant layer 6 made of polyolefin, and the anchor coat layer 2 is formed on the support material 1. The method for forming the polyolefin layer 3 and the aluminum foil layer 4 is not particularly limited.

As described above, in the present invention, since the sealant layer 6 is extrusion coated at a low melting temperature, the oxidative odor of polyethylene does not occur. Furthermore, since the sealant layer 6 has a single-layer structure, it is possible to reduce the number of manufacturing steps for the low-odor packaging material.

[0023]

The present invention will be described in more detail with reference to the following specific examples. Example 1, Comparative Example 1 20 μm thick cellophane 300 (Nimura Chemical Co., Ltd.) as a support material
Manufactured by Nippon Shokubai Kagaku Kogyo Co., Ltd. (Epomin P-1000) with a dry weight of 1.
Apply 0 g / m ² and then apply a thickness of 7
15 μm of soft aluminum foil (manufactured by Tokai Metal Co., Ltd.)
μm low density polyethylene (Mitsui Nisseki Polymer Co., Ltd.
M-11P) was extrusion laminated to form a laminate comprising a support material, a first anchor coat layer, a polyethylene layer and an aluminum foil layer. The melting temperature of the low density polyethylene during extrusion lamination was 320 ° C.

Next, an olefinic anchor coating agent (AC-300 manufactured by Dainippon Ink and Chemicals, Inc.) was applied to the aluminum foil surface of the laminate thus formed, and low density polyethylene (Mitsui Nisseki Polymer Co., Ltd. M-11P) manufactured by M.P.) was extrusion coated to a thickness of 30 μm at a melting temperature of 285 ° C. to obtain a low odor packaging material. The low-odor packaging material thus obtained was processed into a pouch shape to prepare an aluminum pouch (Example 1).

For comparison, the aluminum foil surface of the laminate obtained in Example 1 was coated with a conventional imine type anchor coating agent, and low density polyethylene was extruded to a thickness of 30 μm at a melting temperature of 320 ° C. Rouge coating was performed to obtain a packaging material. The packaging material thus obtained was processed into a small bag shape in the same manner as in Example 1 to obtain an aluminum pouch (Comparative Example 1).

The aluminum pouch thus obtained was tested for adhesion and odor (oxidation odor of polyethylene). The adhesiveness was evaluated by the heat-sealing strength when the surfaces of the aluminum pouches were heat-sealed at 140 ° C. and 1 kg / cm ² for 1 second. Also, as an odor test, put pure water in an aluminum pouch and store it at 50 ° C for 7 days.
The taste of the water was then evaluated. The results are shown in Table 1.

Table 1 Example No. Adhesive odor Example 1 Good None Comparative Example 1 Good Remarkable

As is clear from Table 1, the aluminum pouch of Example 1 had good adhesiveness and had no odor such as the oxidizing odor of polyethylene. On the other hand, Comparative Example 1
In the aluminum pouch, the oxidized odor of polyethylene was transferred to the water after storage.

[0029]

As described above, according to the present invention, a polyolefin-based anchor coating agent is applied to the aluminum foil layer, and the polyolefin-based sealant layer is directly laminated, so that the extrusion temperature of the polyolefin is low. However, the adhesiveness is good. Therefore, single-layer lamination of the polyolefin layer by low-temperature extrusion coating becomes possible. As a result, a low-cost, low-odor packaging material is realized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of a low odor packaging material according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the structure of a conventional low odor packaging material.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Support body 2 ... First anchor coat layer 3 ... Polyolefin layer 4 ... Aluminum foil 5 ... Second anchor coat layer 6 ... Polyolefin-based sealant layer

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location B32B 15/20 B32B 15/20 27/32 27/32 Z B65D 65/40 B65D 65/40 A

Claims (5)

[Claims] 1. A method for producing a low-odor packaging material, wherein an anchor coating agent layer is formed on a barrier layer made of aluminum foil, and then 0.1% by dry weight is formed on the anchor coating agent layer.
A method for producing a low-odor packaging material, which comprises directly laminating a polyolefin-based sealant layer of up to 2.0 g / m ² . 2. The method for producing a low-odor packaging material according to claim 1, wherein a polyolefin layer and the aluminum foil are laminated on a support material layer, and then the anchor coat agent layer and the polyolefin are formed on the aluminum foil. A method for producing a low-odor packaging material, which comprises laminating a base sealant layer. 3. The method for producing a low odor packaging material according to claim 1, wherein the polyolefin-based sealant layer is formed by extrusion coating a polyolefin at a melting temperature of 300 ° C. or lower. A method for manufacturing a low-odor packaging material. 4. The low-odor packaging material according to claim 1, wherein the sealant layer is formed of low-density polyethylene or linear low-density polyethylene. Manufacturing method. 5. The low odor packaging material according to any one of claims 2 to 4, wherein an anchor coat layer is provided between the support material and the polyethylene layer. Manufacturing method.