JP2917035B2 - Laminated film for heat sealing - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a laminated film for heat sealing, particularly to a lid material or a bag for a food packaging container such as a microwave heated food,
Alternatively, the present invention relates to a heat-sealing laminated film suitable for use as a lid material or a bag of a non-food container such as an insect repellent or an aromatic.

[Conventional technology]

2. Description of the Related Art Conventionally, microwaved foods packaged with retort-sterilized cooked rice or the like in various containers or bags have been marketed. When heating such a microwave-heated food in a microwave oven, in order to prevent rupture due to an increase in internal pressure, for example, in the case of a tray type container, a part of the lid material is peeled off, that is, several places with a toothpick or the like. In this case, ventilation or water permeability is provided by making a hole in the hole or peeling off the entire surface of the lid material and covering the fitting lid.

In addition, as an example of packaging that requires ventilation and water permeability, a tea bag can be cited as an example of a food product using a bag. This tea bag uses a nonwoven fabric or a nylon net as an extraction inner bag, and a paper bag or a moisture-proof bag using an aluminum foil as a barrier layer is used as an outer bag.

Further, as non-foods, there are those in which insect repellents are packaged in bags. In this device, tablets containing an insect repellent are individually wrapped in a gas-permeable packaging material such as a nonwoven fabric, and a plurality of the tablets are collectively packaged in a barrier packaging material.

[Problems to be solved by the invention]

However, when heating the microwave oven food, if a part of the lid material is peeled off, moisture evaporation from this part increases, and cooking unevenness may occur. In addition, a tool is required to form a hole in the lid or the bag, and if the hole is insufficiently formed, the pressure in the container increases during cooking, and there is a risk of explosion. In the case of using a fitting lid, there is a problem in terms of packaging material cost.

On the other hand, those using paper as the outer bag as a bag for tea bags and insect repellents are inferior in fragrance retention and moisture resistance, and those using aluminum foil bags are cost and packaging processes. The burden is heavy.

Therefore, an object of the present invention is to provide a laminated film for heat sealing which is suitable as a packaging material for the above-mentioned various foods and non-foods, particularly as a lid material for a container.

[Means for solving the problem]

In order to achieve the above object, the heat-sealing laminated film of the present invention is characterized in that a polyolefin-based resin layer is releasably laminated on one surface of a nonwoven fabric, and a base film is laminated on the polyolefin-based resin layer. Is characterized in that the other surface is a heat seal side surface.

That is, the present invention provides a laminated film in which a base film and a nonwoven fabric having air permeability are laminated in a releasable state.The lid material and the bag body are formed with the laminated film, and immediately before use. An object of the present invention is to provide a laminated film capable of obtaining air permeability or water permeability by peeling a base film.

The present invention will now be described in more detail with reference to the drawings.

1 to 5 show a laminated film for heat sealing according to a first embodiment of the present invention. FIG. 1 is a cross-sectional view of a laminated film showing a basic structure, and FIG. FIG. 3 is a cross-sectional view showing the peeled state of the laminated film shown in FIG. 2, FIG.
FIG. 5 is a cross-sectional view showing a state where the laminated film is used as a lid material of a container, and FIG. 6 to 10 show a laminated film for heat sealing according to a second embodiment of the present invention. FIG. 6 is a sectional view of the laminated film showing the basic structure, and FIG. Sectional view of a laminated film using
FIG. 9 is a cross-sectional view showing a peeled state of the laminated film shown in FIG. 7, FIG. 9 is a cross-sectional view showing a state in which the laminated film is used as a lid material of a container, and FIG. FIG.

First, as shown in FIG. 1, a heat-sealing laminated film 1 according to a first embodiment of the present invention has a polyolefin resin layer 6 releasably laminated on one surface of a nonwoven fabric 3 and the polyolefin resin layer. 6, the base film 2 is laminated, and the other surface of the nonwoven fabric 3 is a heat seal side surface.

As the base film 2, it is preferable to use an aluminum foil having a barrier property, an aluminum vapor-deposited film, nylon, polyvinylidene chloride, a saponified ethylene-vinyl acetate copolymer film or the like. Can be used, such as polyethylene terephthalate, polypropylene, polyethylene, polystyrene, polyvinyl chloride and the like. The above-mentioned various films can be used alone as the base film 2. However, as shown in FIGS. 2 and 3, the above-mentioned films and adhesives (2a, 2b, 2c) are appropriately laminated. Layer films can be used.

On the other hand, the non-woven fabric 3 can be made of polyethylene, polypropylene, polyester, or polyvinyl alcohol resin. In particular, as shown in FIGS. 4 and 5, at least the other surface of the nonwoven fabric 3 on the heat sealing side is heat-sealed to facilitate attachment to the container 4 and formation of the bag 5. It is desirable to provide a possible fiber layer. The fiber thickness of the nonwoven fabric 3 is preferably 0.3 to 5.0 denier, preferably 0.5 to 1.5 denier, and the basis weight is 5 to 100 g / m ² , preferably 15 to 70 g.
/ m ² is desirable.

As the resin of the polyolefin resin layer 6, low density polyethylene, linear polyethylene, a blend of polyethylene and polypropylene, polypropylene, an ethylene-vinyl acetate copolymer resin, or the like can be used. Thereby, it can be melt-extruded and laminated between the base film 2 and the nonwoven fabric 3.

Especially when the nonwoven fabric 3 is a polypropylene resin,
As the polyolefin resin, it is preferable to use low-density polyethylene, linear polyethylene, ethylene-vinyl acetate copolymer resin, or a blend of polyethylene and polypropylene. When a blend of polyethylene and polypropylene is used, the content of polypropylene is 50% by weight so that the polyethylene component becomes rich.
Hereinafter, the content is desirably set to 0 to 30% by weight.
As a result, it is possible to obtain a laminated state that can be peeled off from the nonwoven fabric 3 without increasing the heat fusion strength.

When the nonwoven fabric 3 is a polyester resin, low-density polyethylene, linear polyethylene, polypropylene, or a blend of polyethylene and polypropylene can be used as the polyolefin resin.

The polyolefin-based resin layer 6 has a generally used adhesive (anchor coating agent; AC agent) such as a polyurethane-based resin at the interface on the base film 2 side in order to strengthen the adhesive force with the base film 2. ) It is preferable to provide a layer. Furthermore, by coating one surface of the nonwoven fabric 3 on the base film side with a thin polyolefin resin, the smoothness of one surface of the nonwoven fabric 3 is improved, and the releasability from the polyolefin resin layer 6 is improved. Can be improved.

The laminated film 1 for heat sealing having such a configuration is as follows.
As shown in FIG. 4 and FIG.
It is suitably used as a forming material of the. When the content is heated by a microwave oven or when air permeability or water permeability is required, only the base film 2 of the laminated film 1 may be peeled from the nonwoven fabric 3.

In particular, when used as a lid material for a container, it is preferable to use the laminated film for heat sealing of the second embodiment of the present invention. That is, as shown in FIGS. 6 to 10, the heat-sealing laminated film 11 of the second embodiment of the present invention has a base film 2 and a polyolefin resin formed in the same manner as the first embodiment. In the laminated film in which the layer 6 and the nonwoven fabric 3 are laminated, the easy peel layer 12 is laminated on the other surface which is the heat seal side surface of the nonwoven fabric 3. In this manner, by providing the easy peel layer 12 on the side of the nonwoven fabric 3 attached to the container 4 or on the other surface which is the heat seal side of the bag body 5, the nonwoven fabric 3 can be peeled off from the container 4, It is formed so that the body 5 can be easily opened.

Examples of the easy-peel material forming the easy-peel layer 12 include ethylene-vinyl acetate copolymer-based resins, polyethylene resins, blends of polyethylene and polypropylene, and the like. These resin films can be laminated on the nonwoven fabric 3 by dry lamination and extrusion sand lamination with an adhesive resin. Also, a multilayer film having these resins as outer layers can be used.

When the easy peel layer 12 is laminated on the non-woven fabric 3 and the air permeability of the non-woven fabric 3 is impaired, from the side of the easy peel layer 12 of the non-woven fabric 3 on which the easy peel material is laminated to the three non-woven fabrics by the hot needle method. It is necessary to form a through hole to reach. In the case of laminating the easy peel film on the nonwoven fabric 3, if the film is subjected to a perforating process in advance, the air permeability can be secured.

Further, when heat resistance is not so required, if a heat-shrinkable film is used as the base film 2, there is an effect that the film is heated by a microwave oven or the like and peeled off by a contraction force without being peeled by hand.

〔Example〕

Hereinafter, embodiments of the present invention will be described. The measurement of the adhesive strength was performed at a pulling speed of 200 mm / min and 180 ° peeling.

Example 1 Biaxially stretched polyethylene terephthalate film 12μ / adhesive / polyethylene film 35 as base film
and a nonwoven fabric of polyester fiber / polypropylene fiber (HISTA EP manufactured by Hirose Paper Co., Ltd.)
(05) -50; basis weight 50 g / m ² ; fiber 0.5 denier), and as a polyolefin resin, 10% by weight of polypropylene +
A blend of 90% by weight low density polyethylene was used.

While the base film is fed from the primary side of the extrusion laminator and the non-woven fabric is simultaneously fed from the secondary side, the polyolefin resin is extruded from the T-die die between the polyethylene side of the base film and the polyester side of the non-woven fabric. I took it.

The adhesive strength between the base film and the polyolefin resin of the laminated film produced in this manner could not be measured due to breakage of the polyolefin resin layer. The adhesive strength between the polyolefin resin and the nonwoven fabric was 200 g / 15 mm width.

Then, with the nonwoven fabric side of the obtained laminated film inside (sealing side), 190 ° C
Heat sealing was performed under the conditions of × 2 kg / cm ² × 2 seconds. The adhesive strength between the heat-sealed polyolefin resin and the nonwoven fabric at the heat-sealed portion was 1200 g / 15 mm width, and the base film / polyolefin resin layer and the nonwoven fabric were peeled by hand, and the appearance was good.

Example 2 A laminate having a structure of biaxially stretched polyethylene terephthalate film 12μ / adhesive / aluminum foil 16μ as a base film, polypropylene as a polyolefin resin,
As the nonwoven fabric, the same nonwoven fabric as that used in Example 1 except that a polyester film (30 μ) was thermally laminated on the polyester resin side was used.

Then, in the same manner as in Example 1, a polyolefin resin was extruded between the aluminum foil side of the base film and the polyethylene film laminate side of the nonwoven fabric to produce a laminated film.

The adhesive strength between the base film and the polyolefin resin of the obtained laminated film was 1600 g / 15 mm width, and the adhesive strength between the polyolefin resin and the nonwoven fabric was 100 g / 15 mm width.

After heat-sealing this laminated film in a polypropylene container under the same conditions as in Example 1, the adhesive strength at the seal between the polyolefin resin and the nonwoven fabric was 1600 g / 15 mm.
The width was good, and the peelability and appearance of the base film / polyolefin resin layer and the nonwoven fabric by hand were good.

Example 3 The same base film, nonwoven fabric and polyolefin resin as those in Example 2 were used, and CMPS 013; 30μ manufactured by Tosello Co., Ltd. was used as an easy peel material.

The above-mentioned Easy Peel material is fed out from the primary side of the extrusion laminator, and a polyurethane adhesive (AC agent) is applied. It was extruded between polyethylene and pressed and wound up. Next, through holes having a hole diameter of 0.6 mm and an interval of 5 mm × 7 mm were formed in a lattice shape from the easy peel material side of the laminate by a hot needle method so as to reach the nonwoven fabric interface.

Then, a laminated film was manufactured in the same manner as in Example 1 while feeding the above-mentioned laminate from the secondary side of the extrusion laminator.

The adhesive strength between the base film and the polyolefin resin of the obtained laminated film was 1500 g / 15 mm width, and the adhesive strength between the polyolefin resin and the nonwoven fabric was 100 g / 15 mm width.

Further, after heat-sealing this laminated film to a polypropylene container under the same conditions as in Example 1, the adhesive strength at the seal portion between the polyolefin resin and the nonwoven fabric was 1400 g / 15 mm.
The width was good, and the peelability and appearance of the base film / polyolefin resin layer and the nonwoven fabric by hand were good. Furthermore, the adhesive strength between the nonwoven fabric and the polypropylene container is 1300 g /
The width was 15 mm, and peeling by hand was easy.

Example 4 A round container made of polypropylene (inner diameter 90 mm × depth 70 mm,
150 g of a commercially available frozen food for microwave oven (shrimp pilaf) is housed in a flange portion (5 mm width), and the laminated film produced in Example 3 is placed on a nonwoven fabric side with a 5 mm width sealing mold.
The container was hermetically sealed under the conditions of 90 ° C. × 2 kg / cm ² × 2 sec to obtain a container lid material.

Peel off the base film from the container lid, and use a microwave oven (Matsushita Electric Industrial Co., Ltd., NE-M330 type, rated high-frequency output 500
After heating at 500 W for 3 minutes, steam spouted from the surface of the non-woven fabric, and a shrimp pilaf with good texture without uneven heating could be produced.

Example 5 The same operation as in Example 4 was carried out except that the container was filled with commercially available potage soup and sealed by opening and closing.
A potage soup with good texture was obtained without blowing. Further, the nonwoven fabric when the container was hot could be easily peeled off.

Example 6 The same base film, nonwoven fabric and polyolefin resin as in Example 1 were used, and the same easy peel material as in Example 3 was used.

Then, a laminate including the easy peel material and the nonwoven fabric was produced in the same manner as in Example 3, and then a laminated film was produced in the same procedure as described above.

The adhesive strength between the base film and the polyolefin resin of the obtained laminated film could not be measured due to breakage of the polyolefin resin layer. The adhesive strength between the polyolefin resin and the nonwoven fabric was 180 g / 15 mm width.

After heat-sealing this laminated film to a polypropylene container under the same conditions as in Example 1, the adhesive strength at the seal between the polyolefin resin and the nonwoven fabric was 1000 g / 15 mm.
The width was good, and the peelability and appearance of the base film / polyolefin resin layer and the nonwoven fabric by hand were good. Furthermore, the adhesive strength between the nonwoven fabric and the polypropylene container is 1300 g /
The width was 15 mm, and peeling by hand was easy.

〔The invention's effect〕

As described above, the heat-sealing laminated film of the present invention laminates a polyolefin-based resin layer on one surface of a nonwoven fabric in a releasable manner, and laminates a base film on the polyolefin-based resin layer to form the other of the nonwoven fabric. Since the surface of the substrate is a heat-sealed side surface, the nonwoven fabric is exposed by exfoliating the base film, and air permeability is exhibited, so that it can be widely used as the packaging material for foods and non-foods. In addition, the present double wrapping is unnecessary for the wrapping body corresponding to a tea bag, a bag, or the like, and the function can be exhibited by the present wrapping film alone. In addition, konjac and soybeans are wrapped with the laminated film of the present invention together with water, and only the water is discharged from the nonwoven fabric of the inner layer by peeling off only the outer layer base film at the time of use. Can be demonstrated.

Further, by providing the easy peel layer, the releasability when the laminated film is used as a lid material for a container can be improved.

[Brief description of the drawings]

1 to 5 show a laminated film for heat sealing according to a first embodiment of the present invention. FIG. 1 is a cross-sectional view of a laminated film showing a basic structure, and FIG. Sectional view of the laminated film used, FIG.
FIG. 4 is a sectional view showing a state in which the laminated film is peeled off, FIG. 4 is a sectional view showing a state in which the laminated film is used as a lid material of a container, and FIG. 6 to 10 show a laminated film for heat sealing according to a second embodiment of the present invention. FIG. 6 is a sectional view of the laminated film showing the basic structure, and FIG. FIG. 8 is a cross-sectional view showing a peeled state of the laminated film shown in FIG. 7,
FIG. 9 is a cross-sectional view showing a state in which the laminated film is used as a lid material for a container, and FIG. 10 is a cross-sectional view showing a state in which the laminated film is similarly used as a bag. 1,11 ... Laminated film for heat sealing, 2 ... Base film, 3 ... Non-woven fabric, 6 ... Polyolefin resin layer, 12 ... Easy peel layer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI B32B 27/12 B32B 27/12 B65D 43/00 B65D 43/00 65/40 65/40 A 81/34 81/34 V

Claims (1)

(57) [Claims] 1. A polyolefin resin layer is releasably laminated on one surface of a nonwoven fabric, a base film is laminated on the polyolefin resin layer, and the other surface of the nonwoven fabric is a heat seal side surface. Laminated film.