JPH0584871A - Packing container - Google Patents

Abstract

PURPOSE:To ensure the good freshness holding state of a packing container without generating the slime of an inner surface, the transfer of a freshness keeping agent or the lowering of strength by successively bonding a synthetic resin film and inner surface paper to a base material and turning the inner surface paper inwardly. CONSTITUTION:In a packing container of an object to be packed having moisture transpiraion properties such as vegetables and fruits or cut flowers, a packing material consisting of a synthetic resin film 2 and inner surface paper 3 is bonded to a base material through an adhesive 4 so as to turn the inner surface paper 3 inwardly. At this time, as the base material 1, for example, kraft paper or corrugated cardboard is used. As the synthetic resin film 2, for example, a stretched polystyrene film is used. Further, as the inner surface paper, paper having high water absorbability is used and a freshness keeping agent is applied thereto. The good freshness keeping state of the packing container is ensured without generating the slime of an inner surface, the transfer of the freshness keeping agent or the lowering strength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging container such as a packaging bag or a packaging box used for packaging an object to be packaged such as fruits and vegetables and cut flowers having moisture transpiration.

[0002]

2. Description of the Related Art Heretofore, the following packaging containers have been known to be used for packaging objects to be packaged which have a water vaporizing property.

(1) A corrugated cardboard box (Japanese Patent Publication No. 62-47712) formed by using a corrugated cardboard with a synthetic resin film adhered on one side, with the synthetic resin film side facing inward.

(2) A corrugated cardboard having a synthetic resin film coated with a freshness-retaining agent such as an ethylene adsorbent and a water-absorbing agent such as a highly water-absorbent resin adhered on one side is used, and the surface on which the freshness-retaining agent or the water-absorbing agent is coated is placed inside Cardboard box formed by
01245).

(3) A cardboard box formed by using a cardboard mixed with a freshness-retaining agent such as an ethylene adsorbent.

[0006]

However, in the case of the packaging container of the above (1), the water evaporated from the object to be packaged is condensed and adheres to the inner surface of the container, and the water droplets wet the object to be decomposed. Is likely to occur and it is difficult to maintain freshness.

Further, in the case of the packaging container of the above (2), although water droplets do not adhere, an uncomfortable feeling such as a slimy inner surface occurs due to the influence of water, and a synthetic resin film is used as a freshness-retaining agent or a water-absorbing agent. The holding power is weak, and there is a problem that these are easily transferred to the packaged object.

Further, in the case of the packaging container of the above (3), since the corrugated board itself easily absorbs water because the freshness-retaining agent is mixed, the corrugated board absorbs the water evaporated from the object to be packaged, so that the strength of the packaging container is increased. There is a problem that the product to be packaged is easily deteriorated and the packaged product is easily withered, so that the freshness preservation state is poor.

The present invention has been made in view of the above conventional problems, and a packaging container in which a good freshness-retaining state can be obtained without causing slime on the inner surface, migration of the freshness-retaining agent, and reduction in strength. The purpose is to

[0010]

To this end, in the present invention,
As shown in FIG. 1, it is composed of a packaging material including a base material 1, a synthetic resin film 2 adhered to the base material 1, and an inner surface paper 3 further adhered to the synthetic resin film 2. The packaging container has three sides facing inward.

The present packaging container is suitable for packaging an object to be packaged, such as fruits and vegetables, cut flowers, etc., having moisture transpiration, and may be a bag or a box.

As the base material 1 in the present invention, when the present packaging container is used as a bag, general paper for packaging such as kraft paper is used. Also, when this packaging container is a box,
For example, cardboard and cardboard are used.

As the synthetic resin film 2, for example, a stretched or non-stretched film of polystyrene, polypropylene, polyethylene, polyester, polyvinyl chloride or the like can be used, but it has appropriate water vapor permeability and gas permeability, and has a low elasticity. Stretched polystyrene films are preferred because they are strong.

The inner surface paper 3 forms the inner surface of the present packaging container, and ordinary paper is used, but paper having high water absorption is preferable, and paper having water absorption of 10 to 200 g / m ² is particularly preferable. If the water absorption rate is too low, water droplets tend to adhere to the article to be packaged, and if the water absorption rate is too high, the article to be packaged tends to wilt.

The inner paper 3 preferably has a freshness-retaining agent. The freshness-retaining agent can be applied to the inner surface paper 3 by impregnation or coating. As the freshness-retaining agent, those having ethylene adsorption property can be widely used, and for example, zeolite, Otani stone, activated carbon and the like are used. Since the inner surface paper 3 is a fibrous material, it can strongly retain the freshness-retaining agent, so that it is possible to prevent the freshness-retaining agent from migrating to the object to be packaged, and the effect of the freshness-retaining agent improves the freshness-retaining effect. Can be increased.

Adhesion between the base material 1 and the synthetic resin film 2 and between the synthetic resin film 2 and the inner surface paper 3 is performed with an adhesive 4. As the adhesive 4, the synthetic resin film 2 and the paper to be used are Any adhesive can be used, and for example, ethylene-vinyl acetate, a rubber-based hot-melt adhesive, a polyethylene solvent-based adhesive, or the like can be used.

[0017]

The substrate 1 in the present invention provides the strength required for a packaging container.

The synthetic resin film 2 has a function of blocking moisture that evaporates from the object to be packaged and preventing the substrate 1 from absorbing this moisture.

The inner surface paper 3 serves to absorb water and prevent water droplets from adhering to it.

[0020]

【Example】

Example 1 A 16 μm-thick stretched polystyrene film was adhered to one side of a corrugated board via an 8 μm-thick ethylene-vinyl acetate-based hot meth-type adhesive, and further an 8 μm-thick low-density polyethylene-based adhesive was applied onto this. Using a packaging material obtained by adhering a 30 μm thick paper coated with a freshness-keeping agent as an inner surface paper, a cardboard box was formed with the inner surface paper side facing inward.

10 kg of spinach was placed in the cardboard box and left for 3 days at a temperature of 20 ° C. and a humidity of 65% RH, and then the compressive strength of the cardboard box was measured, the state of water droplets adhering to the inner surface of the cardboard box, and the spinach The weight was measured and the appearance was observed.

The results are shown in Table 1.

Comparative Example 1 A packaging material obtained by adhering a stretched polystyrene film having a thickness of 16 μm to one surface of the same corrugated cardboard as in Example 1 through an 8 μm thick ethylene-vinyl acetate-based hot met type adhesive was used as a stretched polystyrene film. In the same manner as in Example 1 except that the side was faced inward, the compressive strength of the cardboard box, the observation of the state of water droplets adhering to the inner surface of the cardboard box, the weight measurement of spinach and the appearance observation were performed.

The results are shown in Table 1.

Comparative Example 2 A 16 μm-thick stretched polystyrene film was adhered to one side of the same corrugated board as in Example 1 through an 8 μm-thick ethylene-vinyl acetate-based hot met type adhesive, and the stretched polystyrene film surface was kept fresh. Of compressive strength of a corrugated cardboard box and corrugated cardboard box in the same manner as in Example 1 except that a packaging material obtained by coating a water absorbent and a water absorbing agent (super absorbent resin) was used with the coated surface facing inward. The state of adhesion of water droplets on the inner surface, the weight measurement of spinach and the appearance observation were performed.

The results are shown in Table 1.

COMPARATIVE EXAMPLE 3 Measurement of the compressive strength of a corrugated cardboard box, observation of water droplet adhesion to the inner surface of the corrugated cardboard box, and measurement of the weight of spinach were carried out in the same manner as in Example 1 except that corrugated cardboard containing an ethylene adsorbent was used. And the appearance was observed.

The results are shown in Table 1.

[0029]

[Table 1]

[0030]

The present invention is as described above and has the following effects.

(1) It is possible to prevent spoilage caused by wetting with water droplets attached to the inner surface of the packaging container.

(2) In particular, a good freshness-retaining effect can be obtained without using a freshness-retaining agent, and when this is used, it is possible to prevent sliming of the inner surface of the packaging container and its migration to the packaged object.

(3) It is possible to prevent a decrease in strength due to water absorption of the constituent material of the packaging container and an excessive absorption of water from the object to be packaged.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a packaging material that constitutes the present packaging container.

[Explanation of symbols]

 1 Base Material 2 Synthetic Resin Film 3 Inner Paper 4 Adhesive

Claims (1)

[Claims] 1. A packaging material comprising a base material, a synthetic resin film adhered to the base material, and an inner surface paper further adhered to the synthetic resin film, wherein the inner paper surface side faces inward. A packaging container characterized by: