JPH10113986A - Laminating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the acquisition of enough fusing strength even when a lamination is performed under a low temperature and short time heating conditions by a method wherein thermal fusing layers are pre-heated at the lamination of two laminate films, on one side of each base material layer of which the thermal fusing layer is provided, under heat and fixation by pressure to each other. SOLUTION: As a laminate film, a laminate, which produces by laminating a thermal fusing layer made of resin film such as polyethylene or the like on one side of a base material layer made of resin film such as a polyester or the like, is employed. The preferable thermal conductivity of the base material layer is 0.2[Jm<-1> sec<-1> K<-1> ] or less. When the thermal conductivity of the base material layer is too large, the thermal fusing layer melts at pre-heating, resulting in making the lamination of the films difficult. As the laminating method of the films, the thermal fusing layers are pre-heated just before the lamination of the two laminate films. The preferable pre-heating temperature is within the range of (the melting point of the thermal fusing layer -50 deg.C)-(the melting point of the thermal fusing layer).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for laminating a laminate film having a heat-sealing layer on one side of a substrate.

[0002]

2. Description of the Related Art Conventionally, when a heat-sealing layer of two laminated films having a heat-sealing layer on one surface of a base material layer is laminated by heating and pressing, the heat-sealing layer of the laminate film is used. A method of heating the heat-sealing layer to a temperature equal to or higher than the melting point and pressing the heat-sealing layer from the back side is performed. In order to heat the heat-fused layer to the melting point or higher by heating from the back side of the heat-fused layer, it was necessary to heat the back side at a temperature considerably higher than the melting point.

[0003] However, when the above-mentioned laminated film is heated at a high temperature, there are problems such as foaming and discoloration of the base material layer. In addition, since the heating time becomes longer, the laminating speed becomes slower,
There was a problem that productivity decreased.

[0004] On the other hand, when heating at a low temperature or heating for a short time, sufficient heat fusion is not performed by lamination, and if the laminated product is used as a packaging bag, it is difficult to obtain sufficient airtightness. There was a point. In particular, when the laminate film is made of paper or the like having a low thermal conductivity as the base layer, such a problem is likely to occur because the heating time becomes long.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to use a laminate film comprising a base layer having a low thermal conductivity and a heat-sealing layer, and to laminate the laminate under a low-temperature and short-time heating condition. Another object of the present invention is to provide a laminating method capable of obtaining a sufficient bonding strength.

[0006]

According to the laminating method of the present invention, a heat-sealing layer of two laminated films having a heat-sealing layer on one side of a substrate layer is laminated by heating and pressing. Preferably, the heat-sealing layer is preheated.

[0007] As the laminate film used in the present invention, a film having a heat-sealing layer on one side of a substrate layer is used. Examples of the base layer include resin films such as polyester, polyolefin, and nylon, as well as single-layer films such as cellophane, paper, and metal foils such as aluminum foil, and laminated films thereof. In addition, examples of the heat-sealing layer include a resin film such as polyethylene.

As the laminate film, for example, a laminate in which a heat sealing layer is laminated on one side of a base material layer is used.

If the thermal conductivity of the base material layer is too large, the pre-heating may cause the heat-fused layer to melt and make lamination difficult, so that the thermal conductivity of the base material layer is 0.2 [Jm ^-1 sec ^-1 K ^-1 ] or less. Is preferred.

In the laminating method of the present invention, the heat-sealing layers are preheated immediately before laminating the two laminated films. The preheating temperature of the heat-sealing layer immediately before laminating is (the melting point of the heat-sealing layer−50 ° C.)
(Melting point of the heat-sealing layer) is preferable. When the preheating temperature is lower than the above range, there is no effect of the preheating, and when the preheating temperature is higher than the above range, the heat-sealing layer protrudes and lamination becomes difficult.

As a method of the above preheating, for example,
A method of directly heating using a sheet heating element, a heat roll, or the like,
Examples thereof include a method of heating with infrared rays and a method of heating through a hot air furnace. Of these methods, it is preferable to preheat the heat-sealing layer because heating is easier and more efficient.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the following examples.

(Examples 1 to 3) A polyethylene terephthalate film having a heat-sealing layer made of polyethylene (manufactured by Dai Nippon Printing Co., Ltd., melting point: about 90 ° C.) and a base layer containing paper as a laminated film having a heat-sealing layer. (12 μm) / polyethylene (15 μm) / high quality paper (60 μm) / polyethylene (40 μm) [manufactured by Dai Nippon Printing Co., Ltd., melting point: about 90 ° C.]. The heat-sealing layer of the two laminated films was used as a sheet heating element (“Samicon Heater Super 3” manufactured by Sakaguchi Electric Heat Co., Ltd.).
40 "), and preheated to the temperature shown in Table 1,
The heat-sealed layers are overlapped with each other and heat-pressed at a heat-sealing temperature shown in Table 1 for 0.5 seconds using a laminate film closing machine (“NW-405” manufactured by Omori Machinery Co., Ltd.) to heat the heat-sealed layers together. Fused.

(Comparative Examples 1 to 4) Except that the preheating temperature and the heat fusion temperature of the heat fusion layer were changed as shown in Table 1,
In the same manner as in Example 1, the heat-sealing layers were heat-sealed to each other.

In the above Examples and Comparative Examples, the heat-sealed portions of the laminated films produced were peeled off by hand, and the peeling state was evaluated by visual observation. The evaluation results are shown in Table 1.

[0016]

[Table 1]

[0017]

The laminating method of the present invention has the above-mentioned structure, and uses a laminated film composed of a base material layer having low thermal conductivity such as paper and a heat-sealing layer at a low temperature and a short time. Even when laminating under heating conditions for a long time, sufficient heat-sealing strength can be obtained.

Claims (3)

[Claims] 1. A heat-sealing layer is preheated when heat-pressing and laminating heat-sealing layers of two laminated films each having a heat-sealing layer on one side of a base material layer. A lamination method characterized by the above-mentioned. 2. A laminate film is formed from a laminate comprising at least two layers of a heat-sealing layer and a base material layer having a thermal conductivity of 0.2 [Jm ^-1 sec ^-1 K ^-1 ] or less. The laminating method according to claim 1, wherein: 3. The pre-heating temperature of the heat-sealing layer immediately before laminating is in the range of (melting point of heat-sealing layer−50 ° C.) to (melting point of heat-sealing layer). 2. The lamination method according to 1.