JP3078052U - Laminates for food packaging - Google Patents

Abstract

(57) [Summary] [Problem] To provide a laminate material for food packaging that can adsorb moisture of food on the inner surface and breathe on the outer surface. SOLUTION: A water-absorbing polymer 4 is applied on the upper surface of a gas-permeable sheet 5, and a perforated film 1 is laminated on the upper surface of a water-absorbing polymer 4 layer with an adhesive 6, and the adhesive 6 is not adhered. The laminated material for food packaging is scattered so as to have a surface, and the non-adhesive surface has a water retaining portion 7.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a food packaging material, and more particularly to a food packaging laminating material for preventing dew condensation.

[0002]

[Prior art]

 Conventionally, various plastic films have been widely used for food packaging materials. It is desirable that the plastic film has a function of preventing discoloration and spoilage of food, and for that purpose, it is necessary to prevent dew condensation on the contact surface with the food, while the gas generated by the moisture of the food on the inner surface is required. Need to be vented out. However, a laminate film satisfying such a function has not been found in the past.

[0003]

[Problems to be solved by the invention]

 In view of the above circumstances, an object of the present invention is to provide a laminate material for food packaging that can adsorb moisture of food on the inner surface of the laminated film and breathe on the outer surface of the film.

[0004]

[Means for Solving the Problems]

 In order to achieve the above object, the present invention comprises a water-absorbing polymer applied to the upper surface of a gas-permeable sheet, and a perforated film laminated on the upper surface of the water-absorbing polymer layer with an adhesive. It is intended to constitute a food packaging laminate material in which the agent is dispersed so as to have a non-adhesive surface and the non-adhesive surface has a water retaining portion.

[0005]

[Embodiment of the invention]

 Hereinafter, the present invention will be described based on the embodiment. FIG. 1 is a partially cutaway perspective view showing an embodiment of the food packaging laminating material of the present invention. FIG. 2 is a longitudinal sectional view showing an embodiment of the food packaging laminating material of the present invention. 3 is a perspective view showing one embodiment of a gluing roll used for processing the laminated material for food packaging of the present invention, and FIG. 4 is an embodiment of a processing state of the laminated material for food packaging of the present invention. FIG. 5 is a schematic perspective view showing the embodiment, and FIG. 5 is a longitudinal sectional view showing one embodiment of a water-absorbing sheet in which a water-absorbing polymer is applied to the upper surface of a non-woven fabric used for a food packaging laminate of the present invention.

[0006] The perforated film 1, which is the uppermost surface of the product of the present invention, is made of polyethylene. However, the material may be various plastic films such as polypropylene. The film 1 has numerous small holes 2 having a diameter of about 150 μm. The size of the perforation hole 2 is appropriate, and is preferably between 100 and 500 μm. Around the perforated hole 2, small projections 3 formed by curing the molten resin are formed.

The perforated film 1 used in the present invention was selected from a series of machine holes (registered trademark) manufactured by Nidaiki Co., Ltd. In this method, the film is passed through an elastic sponge-shaped roll, and a hole 2 is formed from above with a hot needle roll. Therefore, unlike conventional hot-needle processed products, there is no slag. On the hot-needle roll side of this film, the holes are large and small projections 3 are formed around the film. On the elastic sponge roll side, the holes are small and finished to a smooth surface. Therefore, in this embodiment, the small projections 3 that are preferable for bonding are used on the inside, and the smooth surface is used on the outside.

In the figure, reference numeral 4 denotes a water-absorbing polymer, which is applied to the upper surface of a gas permeable sheet 5 made of a nonwoven fabric. In the case of this embodiment, the nonwoven fabric 5 is made by Unitika Co., Ltd. and has a basis weight of 40 g / m.²  Was used. This is a gas-permeable non-woven fabric that allows only gas to pass without passing through moisture. However, the material of the gas permeable sheet 5 is not limited to a non-woven fabric, and may be a polystyrene or butadienoic acid or another plastic film capable of ensuring gas permeability.

The composition of the water-absorbing polymer 4 is as follows. Sunwet 1M-1000 90 parts by weight EVA # 40Y 30 parts by weight Toluene 180 parts by weight Newpole PE-78 1.2 parts by weight

Here, Sunwet 1M-1000 is a water-absorbing polymer manufactured by Sanyo Chemical Industries, Ltd. EVA # 40Y is an adhesive made of an ethylene-vinyl acetate copolymer manufactured by Mitsui Chemicals, Inc. Newpole PE-78 is a surfactant composed of a dispersant manufactured by Sanyo Chemical Industries, Ltd.

On the upper surface of the nonwoven fabric 5, 16 g / m ² of the water absorbing polymer 4 was applied and dried. The water-absorbing sheet 10 shown in FIG. 5 having a coating thickness of about 30 μm and a basis weight of 61 g / m ² (the solid content is 21 g / m ² ) is prepared.

Then, the perforated film 1 is laminated on the upper surface of the water-absorbing polymer layer 4 with an adhesive 6. The adhesive 6 can be selected from EVA and any other material. However, the adhesive 6 is made of a scattered material having a non-adhesive surface, and the non-adhesive surface serves as the water retaining portion 7. In order to adhere the adhesive 6 in a scattered manner, the gluing roll 8 shown in FIG. 3 is used. The gluing roll 8 has a recess 9 intermittently. The glue roll 8 is immersed in a thermosetting or time-curing adhesive 6 to remove the adhesive attached to portions other than the recess 9 with a scraper (not shown). ) And pressed against the upper surface of the water-absorbing polymer layer 4. It should be noted that the intermittent shape of the recess 9 is not limited to the other rectangles in FIG.

The water-absorbing sheet 10 to which the adhesive 6 was scattered was adhered to the perforated film 1 and laminated using a bonding machine as shown in FIG. The inner side of the perforated film 1 is subjected to a corona discharge treatment (not shown) in advance to facilitate adhesion. Since the perforated film 1 of the present embodiment has the small projections 3 on the inside as described above, it has good adhesion and prevents the water retaining portion 7 from sticking.

That is, since the adhesive 6 is scatteredly attached at intervals, a non-adhesive surface is generated between them. Therefore, the moisture of the packaged food is absorbed by the water-absorbing polymer layer 4 through the gas-permeable sheet 5, and the non-adhesive surface becomes the water retaining portion 7 to retain the moisture. 2 can be evaporated.

[0015]

[Effect of the invention]

 Packaging food with the laminated material of the present invention can separate dew water from food, and because of good ventilation, it has a great effect of preventing discoloration and spoilage of food, and greatly contributes to maintaining freshness of food. We were able to.

If the perforated film having the small projections is bonded inside, the water retaining portion without adhesion can be secured between the perforated film and the water absorbing sheet, and the accumulated water does not flow back.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view showing one embodiment of a food packaging laminate of the present invention.

FIG. 2 is a longitudinal sectional view showing an embodiment of the food packaging laminate of the present invention.

FIG. 3 is a perspective view showing one embodiment of a gluing roll used for processing the laminated material for food packaging of the present invention.

FIG. 4 is a schematic perspective view showing one embodiment of a processed state of the food packaging laminate of the present invention.

FIG. 5 is a longitudinal sectional view showing one embodiment of a water-absorbing sheet in which a water-absorbing polymer is applied to an upper surface of a non-woven fabric used for a food packaging laminate of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Perforated film 2 Perforated hole 3 Small protrusion 4 Water-absorbing polymer 5 Gas permeable sheet made of nonwoven fabric 6 Adhesive 7 Water retaining part 8 Gluing roll 9 Glue roll recess 10 Water absorbing sheet

Claims (2)

[Utility model registration claims] 1. A water-absorbing polymer is applied to the upper surface of a gas-permeable sheet, and a perforated film is laminated on the upper surface of the water-absorbing polymer layer with an adhesive, so that the adhesive has a non-adhesive surface. Characterized in that the non-adhesive surface is a water retaining portion in a scattered manner. 2. The food packaging laminate according to claim 1, wherein the perforated film has a smooth surface on the outside and a small projection surface on the inside.