JP7115674B2 - Packaging method using film sheet - Google Patents

Description

TECHNICAL FIELD The present invention relates to a packaging method for heat-treating a film sheet body in which films having different heat shrinkage ratios are laminated, and using it as a cushioning material when packaging an article.

In Patent Document 1 below, as shown in FIG. 6 (6A), a shrinkable film 1 that shrinks with heating and a non-shrinkable film 2 with a smaller thermal shrinkage than this are laminated, and intermittent at the adhesive portion 3. The film sheet body 4 is heated, the shrinkable film 1 is shrunk as shown in FIG. is described as a cushioning material for packaging goods.

When an article is packaged in this way, the film sheet body 4 is preheated to form a cushioning structure in which steps are formed in the non-shrinkable film 2, and then the article is wrapped. After that, there is a method of heating the film sheet body 4 to form a cushioning structure in which steps are formed in the non-shrinkable film 2 (paragraph [0075] of Patent Document 1 below and [0052] of Patent Document 2 below. reference).

Which of these methods should be adopted can be determined appropriately according to the shape and properties of the article to be packaged. , and then heating the film sheet body 4 to form a buffer structure.

JP 2016-141460 A JP 2017-144559 A

By the way, as shown in FIG. 7, when using the film sheet body 4 as described above to package an article 21 such as a beverage bottle, the non-shrinkable film 2 is used as the inner side in contact with the article 21, If the shrinkable film 1 is placed on the outside and is shrunk by heating, the non-shrinkable film 2 will not form normal corrugated steps, and the steps will fall to one side or collapse, resulting in sufficient cushioning. Sometimes I couldn't get sex.

Also, as shown in FIG. 8, if the non-shrinkable film 2 is on the outside and the shrinkable film 1 is on the inner side in contact with the article 21, and the heat is not sufficiently transferred to the shrinkable film 1, the shrinkable film 1 will shrink. In addition to causing defects, if the temperature is too high, the shrinkable film 1 and the non-shrinkable film 2 will be welded, and the non-shrinkable film 2 will not have normal corrugated steps, but coalesced wrinkles. There was a risk that a sufficient buffering property could not be obtained.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a packaging method using a film sheet body in which normal corrugated steps are formed in a non-shrinkable film and packaging with excellent cushioning properties is possible.

In order to solve the above problems, the present invention provides a film sheet body in which a shrinkable film that shrinks when heated and a non-shrinkable film with a smaller thermal shrinkage than the shrinkable film are laminated and intermittently bonded at an adhesive portion. use,
In a packaging method in which an article is wrapped in the film sheet body, the film sheet body is heated to shrink the shrinkable film, and a wave-shaped step is formed in the non-shrinkable film to impart cushioning properties,
The film sheet body is preheated before wrapping the article, thereby shrinking the shrinkable film to an intermediate stage and forming a step in the non-shrinkable film to an intermediate stage,
After that, the film sheet body is heated again in a state where the article is wrapped, and the shrinkable film is shrunk to the final stage, and the non-shrinkable film is subjected to the final shrinkage treatment of forming steps to the final stage. of.

Further, in the preheating process, the shrinkable film is shrunk up to the intermediate stage by 50% to 80% of the shrinkage up to the final stage.

In the packaging method using the film sheet body according to the present invention, preheating is performed to wrap the article with the film sheet body in which the non-shrinkable film is previously formed with corrugations up to an intermediate stage. At this time, the steps are formed to the final stage while the shape of the steps of the non-shrinkable film is maintained.

Therefore, it is possible to form normal corrugated corrugations while suppressing corrugation and corrugation as much as possible.

In addition to placing the non-shrinkable film on the inside and the shrinkable film on the outside, even when the non-shrinkable film is on the outside and the shrinkable film is on the inside, poor shrinkage and welding are less likely to occur and normal Corrugated steps can be formed to provide similar cushioning.

(1A) Perspective view and cross-sectional plan view showing the packaging state after preheating, (1B) Perspective view showing the packaging state after the shrinkage treatment and cross-sectional plan view Schematic side view showing preheating treatment with hot air same as above Schematic side view showing preheating treatment with a hot plate same as above The perspective view which shows the bottle packing state which made the step|step outside same as the above. A perspective view showing a PIB packaging state with the same step inside. (6A) Schematic side view showing the state before heat treatment, (6B) Schematic side view showing the state after heat treatment of the film sheet body A cross-sectional plan view showing a state in which a step flow occurs in bottle packaging with the steps inside. Cross-sectional plan view showing a state in which welding occurs in bottle packaging with the step on the outside

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the present invention, as shown in FIG. 6(A), a shrinkable film 1 that shrinks with heating and a non-shrinkable film 2 with a smaller thermal shrinkage than this are laminated. A film sheet body 4 bonded with linear bonding portions 3 intermittent in parallel with a space is used.

The shrinkable film 1 and the non-shrinkable film 2 are not particularly limited, and known ones can be used. uses medium and low pressure high density polyethylene (HDPE) and linear low density polyethylene (L-LDPE).

As a method for adhering the shrinkable film 1 and the non-shrinkable film 2 at the adhesive portion 3, known methods such as dry lamination, heat fusion of the film itself, high frequency fusion, and ultrasonic fusion can be used. .

The film sheet body 4 is supplied in a wound roll state to an article packaging company, and is unwound from the roll at the time of article packaging.

When such a film sheet body 4 is used to package an article 21 such as a beverage bottle as shown in FIG. Perform preheating.

In this preheating process, the film sheet 4 is heated from the shrinkable film 1 side while being fed in one of the shrinking directions of the shrinkable film 1 as shown in FIG. 2 or 3 .

As a heating method, as shown in FIG. 2, hot air jetted from a nozzle 5 is blown from the shrinkable film 1 side, or as shown in FIG. can be considered.

In such a preheating process, the shrinkable film 1 is shrunk up to the intermediate stage by 50% to 80% of the shrinkage up to the final stage. As a result of this treatment, the non-shrinkable film 2 assumes a gently corrugated shape in which steps are formed to intermediate stages. In FIGS. 2 and 3, the wavy shape of the non-shrinkable film 2 after the main shrinkage treatment, which will be described later, is indicated by a chain double-dashed line.

The shrinkage temperature due to this preheating treatment is set slightly lower than the shrinkage temperature of the main shrinkage treatment, taking into account the allowance for joint sealing of both ends when wrapping the article 21 as described later and the securing of the gap with the article 21 . For example, when the shrinkable film 1 is PET, the temperature should be 65°C to 70°C. Other materials may be suitable at different temperatures.

Thereafter, as shown in FIG. 1(1A), the film sheet body 4 is wound into a cylindrical shape and fused, and both ends thereof are jointed and sealed, and fitted around the outer periphery of the article 21 . In the example of FIG. 1, the non-shrinkable film 2 is the inner side in contact with the article 21, and the shrinkable film 1 is the outer side.

At this time, the inner diameter of the film sheet body 4 in the wound state is larger than the outer diameter of the large diameter portion of the article 21 so that a gap is formed between the film sheet body 4 and the article 21 .

Then, in this state, the film sheet body 4 is heated again to shrink the shrinkable film 1 to the final stage, and perform the main shrinkage treatment to form the steps in the non-shrinkable film 2 to the final stage. The height of the corrugated shape of the film 2 increases, and the outer periphery of the article 21 is clamped by the film sheet body 4 in a state in which the crest of the corrugation is in close contact with the article 21 .

This main shrinking process is performed, for example, by passing the article 21 wrapped in the film sheet body 4 through the hot inside of the shrink tunnel. When the shrinkable film 1 is PET, for example, the shrinkage temperature in this shrinkage treatment is preferably 75°C to 80°C. Other materials may be suitable at different temperatures.

In the packaging method as described above, preheating is performed and the article 21 is wrapped with the film sheet body 4 in which the non-shrinkable film 2 is previously formed with steps up to the intermediate stage. , the steps are formed to the final stage while the shape of the steps of the non-shrinkable film 2 is maintained.

For this reason, it is possible to form normal corrugated corrugations while suppressing corrugation and corrugation as much as possible. .

In addition, as shown in FIG. 4, even when the non-shrinkable film 2 is placed on the outside and the shrinkable film 1 is placed on the inside, poor shrinkage and welding are less likely to occur, and normal corrugated steps can be formed. As described above, the non-shrinkable film 2 is on the inside and the shrinkable film 1 is on the outside.

By the way, in the above-described embodiment, the film sheet body 4 is used to package an article 21 such as a bottle, but as shown in FIG. ) can also be used for packaging.

In this packaging form, for example, an article 22 such as a stack of books is placed on a base plate 7 made of corrugated cardboard, the article 22 is wrapped with the preheated film sheet body 4 together with the base plate 7, and then the main shrinkage treatment is performed. The article 22 is held on the base plate 7, and the article 22 is stored together with the base plate 7 in an outer box made of corrugated cardboard.

When the article 22 is PIB-packaged in this way, the non-shrinkable film 2 is likely to flow or collapse in the portion parallel to the ridge of the article 22, but in the portion perpendicular to the ridge of the article 22, non-shrinkage occurs. Since the tiers of the shrinkable film 2 retain their shape, the article 22 can be firmly cushioned and protected even if a large external force or impact that deforms the outer box is applied.

In the film sheet body 4 used in the packaging method as in each of the above embodiments, the non-shrinkable film 2 does not have corrugated steps yet in the state before preheating, and general air bubbles are formed. Since it is extremely thin compared to the cushioning material, a roll of the same diameter can be wound with a considerable length. purchase frequency can be reduced. Moreover, the storage space for the roll of the film sheet body 4 can be reduced.

Reference Signs List 1 shrinkable film 2 non-shrinkable film 3 adhesive portion 4 film sheet body 5 nozzle 6 hot platen 7 base plate 21, 22 article

Claims (2)

A film sheet body (4) in which a shrinkable film (1) that shrinks when heated and a non-shrinkable film (2) that has a smaller thermal shrinkage than the shrinkable film (1) are laminated and intermittently bonded at an adhesive portion (3). and use
An article is wrapped with the film sheet body (4), the film sheet body (4) is heated to shrink the shrinkable film (1), and the non-shrinkable film (2) is formed with corrugated steps. In a packaging method that provides cushioning by
The film sheet body (4) is subjected to a preheating treatment of preheating before wrapping the article so that the shrinkable film (1) is shrunk to an intermediate stage , and the non-shrinkable film (2) is A gentle wave shape with steps formed up to the intermediate stage,
After that, the film sheet body (4) is heated again while the article is wrapped, and the shrinkable film (1) is shrunk to the final stage , whereby the non-shrinkable film (2) is stepped to the final stage. A packaging method using a film sheet body, characterized in that the non-shrinkable film (2) is formed and the main shrinkage treatment is performed to increase the wave height of the wave shape . 2. The film sheet body according to claim 1, wherein in the preheating process, the shrinkable film (1) is shrunk up to an intermediate stage by 50% to 80% of the shrinkage up to the final stage. by packaging method.

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