JPS5940299Y2 - Mouth seal for polyethylene terephthalate resin bottles - Google Patents

Description

[Detailed description of the invention] The present invention relates to a tight seal at the mouth of polyethylene terephthalate resin extensions, which has extremely high adhesive strength to the polyethylene terephthalate resin extensions, and can be wrapped into rolls by a short heat-sealing operation. Its purpose was to be a complete distant relative of Tokokai.

Conventionally, there are various types of permanently open seals that permanently open the mouth of a synthetic resin weir body, but the most common one is one in which an adhesive layer molded from polyethylene resin is laminated on the bottom surface of aluminum foil. be.

This normally open seal, which is composed of a polyethylene resin adhesive layer laminated on the bottom surface of aluminum foil, has many excellent functions and effects, but recently it has been recognized for its excellent physical properties, safety, non-pollution, and beauty. For rolls made of polyethylene terephthalate resin, the amount of which is being used rapidly due to dryness, etc., a sufficient open effect cannot be obtained due to the poor adhesion between polyethylene and polyethylene terephthalate resin. There has been a strong desire for a permanently open seal that permanently and strongly opens the resin filler.

The present invention was devised in response to the above-mentioned demands, and is constructed by laminating an adhesive layer molded from modified Eval resin on the bottom surface of aluminum foil.

An embodiment of the present invention will be described below with reference to the drawings.

1 in the figure is a roll made of polyethylene terephthalate resin,
A tight seal 3 according to the present invention is welded to tightly close the open end of the space 2 of the roll 1.

The tight seal 3 is constructed by laminating an adhesive layer 5 made of modified Eval resin on the lower surface of an aluminum foil 4, and both the aluminum foil 4 and the adhesive layer 5 have a thickness of about 40 microns.

This normally open seal 3 is mounted on the open end surface of the mouth section 2 in a form that closes the mouth section 2, is heated to a desired temperature in that position, and is pressed against the open end surface of the mouth section 2 to form an adhesive layer 5. The middle part 2 is open at the bottom end.

There are various means for heating the open end of the space between the normally open seals 3, but since it is desirable that the heating operation and the suppressing operation be performed at the same time,
It is advantageous to use high frequency heating or ultrasonic heating for heating.

In addition, modified Eval resin for forming the adhesive layer 5 ◆East α, β
- Ethylene-vinyl acetate copolymer copolymerized with ethylenically unsaturated acids or their anhydrides.

In this way, the normally open seal 3 according to the present invention is heated and pressed to be welded to the open end surface of the mouth portion 2. When the white part 2 open end pressing force is kept constant, it changes greatly depending on the heating time and heating temperature.

As a result of experimenting with the degree of opening of the white part 2 of this tight seal 3, it is clear that under the same pressing force conditions, strong welding is not necessarily achieved by heating at high temperature for a long time. became.

For example, in the case of a short heating time of 1 or 2 seconds, stronger welding was obtained by increasing the heating temperature from 150°C to 175°C and then to 200°C;
In terms of seconds, it was found that stronger welding was obtained when the heating temperature was 175°C than when it was 200°C.

From this, it can be seen that when welding the critical seal 3 according to the present invention, it is desirable to perform the welding operation at a heating temperature of 175° C. to 200° C. for a time of 2 seconds to 3 seconds.

Of course, these experimental results indicate that the pressing force is constant (approximately IK
(approximately 1.5 g), and this is when the thickness of both the aluminum foil 4 and the adhesive layer 5 is set to 40 microns, and if these values change, the heating temperature and heating time conditions will change. Fully expected.

As is clear from the above description, the present invention can be strongly welded to the mouth part 2 of the embankment body 1 made of polyethylene terephthalate resin, and the embankment body 1 can be kept open and strongly and reliably held.
Further, the welding time to the embankment body 1 can be extremely short, and it has excellent functions and effects as a normally open mouth seal in a polyethylene terephthalate resin embankment body.

[Brief explanation of drawings]

FIG. 1 is a cutaway front view of the main parts of a polyethylene terephthalate resin embankment with a chamber side seal according to the present invention, and FIG. 2 is an enlarged view of the portion circled in FIG. 1. Explanation of symbols: 1...Embankment body, 2...Mouth, 3...Room side seal, 4...Aluminum foil, 5...・Adhesive layer.

Claims (1)

[Scope of utility model registration request] The mouth seal 3 in the polyethylene terephthalate resin extension 1 is constructed by laminating an adhesive layer 5 made of modified EVAL resin on the lower surface of an aluminum foil 4, and is heated while being pressed to form the adhesive layer 5. A normally open mouth seal in a polyethylene terephthalate resin extension that is welded to the opening end face of the mouth part 2.