JPH05262327A - Sticking of thermo-contracting plastic film - Google Patents

Abstract

PURPOSE:To eliminate troubles resulting from organic solvents, by hastening the sticking speed of a thermo-contracting plastic film on a material to neatly apply it. CONSTITUTION:A thermo-sensitive adhesive 2 is applied on a thermo-contractive plastic film 1. The thermo-contractive plastic film 1 wound up on the external face of a vessel 3 to be applied and the thermo-sensitive adhesive 2 activated with heat is stuck on the vessel 3. Thereafter, this is heated at a higher temperature than the thermo-contractive temp. of the thermo-contractive plastic film 1. Since the thermo-sensitive adhesive 2 which does not have the adhesive characteristic at the normal temp., is used, it is not necessary to use separable paper. The activation temp. of the thermo-sensitive adhesive 2 is lower than the thermo-contractive temp. of the thermo-contractive plastic film 1 and hence, any deformations are not brought in the thermo-contractive plastic film 1 when activating the thermo-sensitive adhesive 2. Moreover, it is not necessary to use organic solvents owing to use of thermo-sensitive adhesive 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for attaching a heat shrinkable plastic film to the outer circumference of a container or the like.

[0002]

2. Description of the Related Art When a plastic film is wrapped around an outer surface of an adherend such as a glass container, a plastic container or a metal container, and the outer peripheral surface of the adherend has irregularities, the plastic film cannot be adhered and adhered. .. For this purpose, a heat-shrinkable plastic film that heat-shrinks when heated is used. By shrinking, the sticking is performed so as to be in close contact with the outer periphery of the adherend.

When attaching such a heat-shrinkable plastic film to the outer periphery of the adherend, the heat-shrinkable plastic film is formed into a tubular shape, or both ends are bonded and joined together by using an organic solvent or the like. The heat-shrinkable plastic film can be made into a cylindrical shape by using, and this cylindrical heat-shrinkable plastic film can be dropped from the top of the adherend and covered, and then passed through a tunnel heater or the like at a temperature above the heat shrink temperature. It is general that the heat-shrinkable plastic film is brought into close contact with the outer periphery of the adherend by heating.

However, when the cylindrical heat-shrinkable plastic film is dropped onto the object to be adhered to cover the object, the heat-shrinkable plastic film is rubbed or caught by the object to be adhered. There is a problem that the film cannot be placed on the regular position on the outer periphery of the adherend, and the film may not be attached at an accurate position.

Further, a pressure-sensitive adhesive, a hot-melt type adhesive, an organic solvent, etc. are applied to both ends of the back surface of the heat-shrinkable plastic film, and the heat-shrinkable plastic film is wrapped around the adherend and the heat-shrinkable plastic film is stuck. There is also a method in which the heat-shrinkable plastic film is adhered to a part of the kimono and then heated above the heat-shrinkable temperature of the heat-shrinkable plastic film so that the heat-shrinkable plastic film is shrunk to a precise position on the outer periphery of the adherend to be adhered. Part is used.

[0006]

However, even when the heat-shrinkable plastic film is wound around the periphery of the adherend and adhered by the pressure-sensitive adhesive, the hot-melt type adhesive, or the organic solvent, the following problems occur. is there. First, when applying an adhesive to a heat-shrinkable plastic film and sticking to an adherend with this adhesive, it is necessary to attach a release paper to the surface of the adhesive to prevent the adhesive surface from being exposed. When the heat-shrinkable plastic film is attached to the adherend, a step of peeling off the release paper is required, and the sticking speed of the heat-shrinkable plastic film on the adherend becomes slower. There is a problem that it also increases costs.

Next, when a hot-melt type adhesive is applied to the heat-shrinkable plastic film immediately before the heat-shrinkable plastic film is attached to an object to be adhered, the hot-melt type adhesive is usually heated to 150 ° C. or higher. It is applied to a heat-shrinkable plastic film in a heated and melted state by a spraying device or a coating device, and the heat-shrinkable plastic film shrinks due to the heat at the part where the hot-melt type adhesive is applied, resulting in partial There is a problem that the heat-shrinkable plastic film cannot be neatly attached to the adherend due to deformation.

In addition to such a hot melt type adhesive, when an organic solvent is used to bond both ends of a heat-shrinkable plastic film wrapped around the periphery of the adherend, the organic solvent causes fire or work. There is a problem of environmental deterioration. The present invention has been made in view of the above points, it is possible to increase the sticking speed of the heat-shrinkable plastic film to the adherend and to perform a clean sticking, in addition to the problem due to the organic solvent It is an object of the present invention to provide a method for attaching a heat shrinkable plastic film.

[0009]

A method for attaching a heat-shrinkable plastic film according to the present invention comprises applying a heat-sensitive adhesive 2 to a heat-shrinkable plastic film 1 and applying the heat-shrinkable plastic film 1 to the outer periphery of an adherend 3. It is characterized in that the heat-sensitive adhesive 2 which is wound and heated and activated is adhered to the adherend 3 and then heated to the heat shrinkage temperature of the heat shrinkable plastic film 1 or higher.

[0010]

Since the heat-sensitive adhesive 2 is applied to the heat-shrinkable plastic film 1 and used, it is necessary to use a release paper when using the heat-sensitive adhesive 2 which does not exhibit tackiness at room temperature. Moreover, the activation temperature of the heat-sensitive adhesive 2 is lower than the heat-shrinking temperature of the heat-shrinkable plastic film 1, so that the heat-shrinkable plastic film 1 is not deformed when the heat-sensitive adhesive 2 is activated. .. Further, it is not necessary to use an organic solvent when using the heat-sensitive adhesive 2.

[0011]

EXAMPLES The present invention will be described in detail below with reference to examples. As the heat-shrinkable plastic film 1, a commercially available product which is also called a shrink film can be used as it is, and for example, a film of polyvinyl chloride, polystyrene, polyethylene terephthalate, polypropylene or the like can be used. . The heat-shrinkable plastic film 1 can be subjected to various kinds of printing such as gravure printing.

The heat-sensitive adhesive 2 is mainly composed of a crystalline plasticizer such as dicyclohexyl phthalate (DCHP) and a tackifier such as styrene resin, styrene butadiene resin, acrylic resin and rosin resin. It is prepared by adding a lubricant, a stabilizer and the like.
Those provided in Japanese Patent No. 1835 and Japanese Patent Laid-Open No. 1-96274 can be used. This heat-sensitive adhesive 2 (also called a delayed tack adhesive) does not exhibit tackiness at room temperature, but is instantly activated and tacked by heating above the melting temperature (activation temperature) of the crystalline plasticizer. It is what manifests sex. Therefore, even if this heat-sensitive adhesive 2 is applied to the heat-shrinkable plastic film 1, there is no need to use release paper or the like because it is not tacky when stored at room temperature, and the heat-sensitive adhesive can be simply heated. Since the adhesiveness of 2 can be generated, the heat-shrinkable plastic film 1 can be easily attached to the adherend 3.

The heat-sensitive adhesive 2 is partially applied to the front and rear ends of the back surface of the heat-shrinkable plastic film 1. The coating can be carried out by any coating machine such as a gravure printing machine, a roll coater, a knife coater or the like which has been generally used for coating the heat-sensitive adhesive. When the heat-sensitive adhesive 2 is partially applied to the back surface of the heat-shrinkable plastic film 1, it is preferable to apply it to both end portions of the heat-shrinkable plastic film 1 as shown in FIG.
In this case, as shown in FIG. 2 (b), the heat-sensitive adhesive 2 is applied to both end edges of the long strip-shaped heat-shrinkable plastic film 1 wound around the roll 5, and the heat-sensitive adhesive 2 is applied by using a labeler or the like as shown by a chain line. It is better to use it separately (Fig. 2
The parting line is indicated by a chain line in (b)).

When the heat-shrinkable plastic film 1 coated with the heat-sensitive adhesive 2 as described above is wrapped around the adherend 3 such as a glass container, a plastic container or a metal container, and attached, first, as shown in FIG. After separating the heat-shrinkable plastic film 1 as shown in (a), the heat-sensitive adhesive 2 is heated and activated by a heater or the like. The temperature required to activate the heat sensitive adhesive 2 is usually 60 to 8
Since it is 0 ° C. or lower and this temperature is lower than the shrinking temperature of the heat-shrinkable plastic film 1 (generally 100 ° C. or higher), there is no possibility that the heat-shrinkable plastic film 1 is thermally shrunk and deformed. After activating the heat-sensitive adhesive 2 in this way, the heat-shrinkable plastic film 1 is wrapped around the adherend 3 as shown in FIG. At the same time, the heat-shrinkable plastic film 1 is pasted onto the surface of the adherend 3 at 2, and the end portions of the heat-shrinkable plastic film 1 are overlapped and pasted with the thermosensitive adhesive 2. Since the heat-shrinkable plastic film 1 can be attached by wrapping it around the adherend 3, when the heat-shrinkable plastic film 1 is formed into a tubular shape and is dropped from the adherend 3 to be covered, As described above, the heat-shrinkable plastic film 1 and the adherend 3 can be attached at an accurate position without fear of friction or catching. Further, the heat-sensitive adhesive 2 applied to the heat-shrinkable plastic film 1 as described above.
In activating the heat-sensitive adhesive 2, in addition to directly heating the heat-sensitive adhesive 2 with a blower type heater, a heating drum, or the like, when the adherend 3 itself has heat, the heat-sensitive adhesive may be heated by the heat of the adherend 3. 2 may be heated and activated.

After that, the heat-shrinkable plastic film 1 is heated to a temperature equal to or higher than the shrinkage temperature through a tunnel type heating device or the like to shrink the heat-shrinkable plastic film 1 to produce the heat-shrinkable plastic film 1 as shown in FIG. 1 (b). The heat-shrinkable plastic film 1 can be adhered to the outer periphery of the adherend 3 along the irregularities thereof, and the heat-shrinkable plastic film 1 can be wound and adhered to the adherend 3 in a state of being in close contact with the surface. It is a thing. Here, as the heat-shrinkable plastic film 1 shrinks, a tensile force acts on the part where the end portions of the heat-shrinkable plastic film 1 are bonded together, but the heat-sensitive adhesive 2 has a high viscosity even when activated. Moreover, there is no possibility that the bonding will be peeled off by heating for a short time of about 5 seconds. Therefore, the heating time of the heat-shrinkable plastic film 1 is preferably set to about 5 seconds or less.

Next, a specific example of the present invention will be shown. 30 μm thick heat shrinkable plastic film made of polyvinyl chloride 1
Gravure printing is applied to the back side of the product, and DL-DL manufactured by Dainippon Ink and Chemicals, Inc.
"A-1" was applied using a printing coater. Further, as the adherend 3, a substantially conical shape having a smaller diameter toward the upper part, and rib-like irregularities provided at the upper and lower central portions over the entire circumference was used. Then, the heat-sensitive adhesive 2 was heated to 65 ° C. with a blower type heater using a labeler to be activated, and the heat-shrinkable plastic film 1 was wrapped around the outer periphery of the adherend 3 to be supplied 1000 pieces per minute. .. After this 1
By heating the heat-shrinkable plastic film 1 by passing it through the tunnel type heating device set at 60 ° C.,
The heat shrinkable plastic film 1 was shrunk. As a result, all the heat-shrinkable plastic films 1 were firmly attached to the predetermined positions without looseness. In addition, the adherend 3 which is heated by putting hot water of 90 ° C. into the container forming the adherend 3 is used, and the adherend 3 is heated without heating the heat-sensitive adhesive 2.
The same as above, except that it was wrapped around the outer periphery of the. Also in this case, the heat-shrinkable plastic film 1 was all firmly attached to the predetermined position without looseness.

[0017]

As described above, the present invention applies a heat-sensitive adhesive to a heat-shrinkable plastic film, winds the heat-shrinkable plastic film around the adherend such as a container, and heat-activates the heat-sensitive adhesive. Was adhered to an adherend, and after that, the heat-shrinkable plastic film was heated to a temperature not lower than the heat-shrinkable temperature. Since it is not necessary to use release paper to use a heat-sensitive adhesive that is not shown, the step of peeling the release paper is not required, the sticking speed can be increased, the cost is low, and the heat sensitivity is also low. The activation temperature of the adhesive is lower than the heat shrink temperature of heat shrink plastic film,
The heat-shrinkable plastic film is not deformed when the heat-sensitive adhesive is activated, and the heat-shrinkable plastic film can be attached neatly. Furthermore, since it is not necessary to use an organic solvent in order to use the heat-sensitive adhesive, there is no problem of fire or deterioration of working environment.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention (a),
(B) is a perspective view, respectively.

2A and 2B show the heat-shrinkable plastic film of the above, wherein FIG. 2A is a front view and FIG. 2B is a perspective view.

[Explanation of symbols]

 1 heat-shrinkable plastic film 2 heat-sensitive adhesive 3 adherend

Claims (1)

[Claims] 1. A heat-shrinkable plastic film is coated with a heat-sensitive adhesive, the heat-shrinkable plastic film is wrapped around the adherend, and the heat-activated heat-sensitive adhesive is adhered to the adherend. A method for attaching a heat-shrinkable plastic film, comprising heating the heat-shrinkable plastic film to a temperature not lower than the heat-shrinkable temperature.