JPH0818616B2 - Oversea film heat seal method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) In the present invention, a biaxially stretched synthetic resin film or cellophane coated with vinylidene chloride or a varnish or lacquer is coated on a polystyrene foam container and heat-sealed. Regarding the method.

(Background of the Invention) First, a film will be described.

In general, covering with a transparent film and heat sealing is a method often used for packaging paper boxes, plastic boxes, and the like.

The film used for such packaging is a biaxially stretched synthetic resin film or cellophane coated on both sides with vinylidene chloride or varnish or lacquer. Then, the coating agent is adhered, and then pressure bonding is performed to complete the heat sealing.

The biaxially stretched synthetic resin film is a biaxially stretched polypropylene, polyethylene, polyethylene terephthalate, polyamide resin or the like.

A coating agent consisting of vinylidene chloride, varnish, lacquer, etc., begins to adhere at about 90 ° C, and the heating time required for softening becomes shorter as the temperature rises.
When heated at about 5 ° C. to 140 ° C. for 1 second, the biaxially stretched synthetic resin film and cellophane contract, and the heat-sealed portion becomes rattling.

 Next, the styrofoam will be described.

As is well known, Styrofoam has excellent heat insulating properties at low temperatures, and is often used as a container for products such as ice cream that require cold insulation.

Styrofoam has a characteristic that when it is heated at about 80 ° C. for 6 minutes, secondary foaming occurs, and as the heating temperature increases, the time for secondary foaming becomes shorter.

(Problems to be Solved by the Invention) Items such as the date of manufacture and the company name are usually printed on the Styrofoam container that stores the contents such as ice cream.

However, as described above, the temperature at which Styrofoam causes secondary foaming is because the film is heat-sealed.
It is lower than the temperature for bonding vinylidene chloride or varnish or lacquer. Therefore, depending on the relationship between the heating temperature and the heating time for heat sealing, Styrofoam causes secondary foaming, which causes printing on the container surface. There is a problem that the matters that have been done disappear or become unclear.

(Means for Solving Problems) The present invention is intended to solve the above problems, and as a technical means therefor, vinylidene chloride is formed on both surfaces of a biaxially stretched synthetic resin film or cellophane. Alternatively, when coating a film coated with varnish or lacquer on a Styrofoam container and heat sealing, a heating temperature of 102 ° C. to 118 ° C. and a heating time of 0.
The heat-sealing method for the overlap film was configured such that the heat-sealing was performed for 5 seconds to 3 seconds.

(Function and Effect) According to the method of the present invention, since the heating temperature is 102 ° C. to 118 ° C., it is possible to bond vinylidene chloride or varnish or lacquer without causing shrinkage of the biaxially stretched synthetic resin film or cellophane, Further, since the heating time is set to 0.5 seconds to 3 seconds, secondary foaming of the Styrofoam does not occur, and the printed matter on the container does not disappear or become unclear.

Therefore, it becomes possible to use a biaxially stretched synthetic resin film or cellophane having low water permeability and high airtightness for packaging of a styrofoam container, and the storability and aroma retention of the product are improved.

(Example) Hereinafter, an example of the method of the present invention will be described with reference to the drawings.

FIG. 1 shows a product (A) packaged by the method of the present invention.

The product (A) is formed by covering the polystyrene foam container (B) with the film (C).

The film (C) is a biaxially stretched synthetic resin film or cellophane coated with vinylidene chloride, varnish or lacquer, or laminated.

What is shown in FIG. 2 is a Styrofoam container (B), on the side surface (B ₁ ) and side surface (B ₂ ) of which items such as date of manufacture, company name, etc. are printed, and FIG. As shown in FIG. 3, the styrofoam container (B) contains contents (1) ... such as ice cream.

It should be noted that in view of the fact that the higher the density of the foam, the less likely it is to be affected by heat when performing heat sealing. In this example, expanded polystyrene having a foaming ratio of about 20 to 30 is used.

The packaging of the film (C) in such a polystyrene foam container (B) is performed as follows.

First, as shown in FIG. 4, the film (C) is wound around the styrofoam container (B), and the heater bar (2) is brought into contact with the film (C) so that the film-adhered portion (C ₁ ) is overlapped.
Heat seal.

The heat sealing can be performed by crimping the heater bar (2), but the invention is not limited to this. For example, the heater bar (2) is fixed and the product (A) is the heater bar. It is also possible to move along (2) so that heat sealing is performed during the movement.

The heat sealing is performed at a heating temperature of 102 ° C. to 118 ° C. and a heating time of 0.5 seconds to 3 seconds.

Next, as shown in FIG. 5, the film (C) is aligned with the side surface (B ₁ ) of the Styrofoam container (B), so-called edge folding is performed, and the heater bars (2 ′) and (2 ′) are brought into contact with each other,
The edge-folded portion (C ₂ ) where the film (C) overlaps is heat-sealed.

As with the body sticking part (C ₁ ), heat sealing is performed at the heating temperature.
It is carried out at 102 ° C. to 118 and a heating time of 0.5 seconds to 3 seconds.

However, even if polypropylene, polyethylene, polyethylene terephthalate, a film obtained by biaxially stretching a polyamide resin or the like or a film coated with vinylidene chloride or varnish or lacquer on both sides of cellophane is coated on a polystyrene foam container and heat-sealed, It is possible to obtain a product excellent in storability and aroma retention in which a film is packaged without causing secondary foaming, making the printed matter applied to the Styrofoam unclear.

The present invention is not limited to the above embodiment, and is formed by inserting the Styrofoam container (B ') into the case (3) of a rectangular tube made of paper or the like as shown in FIG. 6, for example. When the film is packaged in a container, the method of the present invention may be used only when heat sealing is performed on the side surface (B ' ₂ ), and an arbitrary heating temperature may be used when heat sealing is performed on the side surface (B' ₁ ). The heating time can be set.

[Brief description of drawings]

FIG. 1 is an overall view of a product according to the present invention. FIG. 2 is an overall view of a Styrofoam container. FIG. 3 is a cross-sectional view of a Styrofoam container. FIG. 4 is a view showing heat sealing of a body-attached portion. FIG. 6 is a diagram showing a heat seal of FIG. 6 is a diagram for explaining a modified embodiment of the present invention. A: Product B: Styrofoam container C: Film 1 ... Contents 2 ... Heater bar 3 ... Case

Claims (1)

[Claims] 1. A biaxially stretched synthetic resin film or a film of cellophane coated with vinylidene chloride or a varnish or lacquer on a Styrofoam container and heat-sealed at a heating temperature of 102 ° C. to 118 ° C. for a heating time. A method for heat-sealing an overlapping film, wherein heat-sealing is performed for 0.5 to 3 seconds.