JPH0430342B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a stopper for sealing a bottle, and more specifically to a sparkling wine stopper made of synthetic resin.

Conventionally, wine stoppers used to seal wine bottle openings are made by hollowing out natural cork bark into a cylindrical shape. Its breathability also helped the fermentation of wine.
Cork bark is the best material to perform these contradictory actions, but cork oaks, which are comparable to wine stoppers, can only grow in a small area along the Mediterranean coast, so they are inevitably in short supply and expensive. Furthermore, it was extremely poor in mass production.

In order to overcome this drawback, various wine stoppers have been developed that are made by foaming inexpensive synthetic resin materials. In either case, the foaming became too uniform over the entire stopper and the compression set became too large, making it impossible to maintain sealing performance that could withstand long-term sealed storage.

The object of the present invention is to eliminate many of these drawbacks and to provide a synthetic resin wine stopper that is inexpensive, has a high compression recovery rate, and is excellent in mass production.

The present invention is a method for manufacturing a synthetic resin wine stopper for sealing the mouth of a wine bottle, etc., and the synthetic resin material may be polyethylene resin, polyethylene-vinyl acetate copolymer resin, or polyethylene resin and polyethylene-vinyl acetate copolymer resin. A mixed resin with a copolymer resin or a synthetic resin made by adding polypropylene resin to the above-mentioned synthetic resin material is used, and an appropriate amount of an organic blowing agent such as azodicarbonamide is added thereto and heated to the foaming temperature. extrusion molding into a desired shape, then cutting into desired dimensions to obtain a rod-like object, inserting the rod-like object into a mold having a desired diameter and length and at least a temperature lower than the temperature of the rod-like object, and sealing it. This is a manufacturing method in which the desired wine stopper is obtained by removing the bottle after applying reduced pressure.

At this time, the rod-shaped object extruded and cut from the extrusion device is selected to have the optimum size for the amount of foaming so that it can be smoothly inserted into a mold having an inner diameter approximately the same as the outer diameter of the desired wine stopper.

An example of implementation will be shown below.

Example The following synthetic resin composition is blended.

Polyethylene resin 100 parts by weight (Sumikasen F1103) Azodicarbonamide 0.25 parts by weight (Otsuka Chemical AZ-S) Foaming aid 0.08 parts by weight (urea-based) Nucleating agent 0.2 parts by weight (calcium stearate) Resin composition with the above formulation is extruded under extrusion conditions of 80°C to 170°C, and the extruded rod is inserted into a molded aluminum pipe at room temperature (600 to 700 mm in length is preferred for work efficiency) with an inner diameter that is approximately the same as the outer diameter of the wine stopper. Insert the pipe, seal one end of the pipe, and vacuum the other end.
It may be Hg or more and 300cmHg or less. ) was added and the pressure was reduced.

Thereafter, when the temperature of the pipe and the rod-shaped material foaming within the pipe decreased to 50° C. or lower, the foamed rod-shaped material was taken out and cut into a predetermined size to obtain a desired wine stopper.

The resulting wine stopper is well foamed in the center, has a density gradient from the center to the outer periphery, and has a solid layer at the outer periphery. A total specific gravity of 0.45 to 0.50 was obtained for this wine stopper.

Note that the numerical values in each of the above examples do not limit the present invention.

As described above, in the synthetic resin wine stopper of the present invention, the synthetic resin in the middle of foaming comes into contact with the pipe whose temperature is lower than the foaming temperature, and the temperature of the outer periphery rapidly decreases, so that the foaming action of the outer periphery and its vicinity is suppressed. At this time, negative pressure is applied to the center to promote the foaming action in the vicinity of the center, and this foam structure allows the center and outer periphery of the synthetic resin foam to be compressed. It was possible to change the foam density.

The characteristic of this synthetic resin wine stopper with a density gradient is that the outer periphery is relatively hard, while the center is moderately soft, so compression is applied from the periphery of the synthetic resin wine stopper. When compressed, the foam layer in the center flexibly deforms and can be easily plugged. Furthermore, the surface of the outer periphery has sufficient strength to withstand external impacts due to its unfoamed structure, and furthermore, since the surface is smooth, it tightly adheres to the mouth of the bottle, etc., producing an extremely strong sealing force.

In this way, synthetic resin wine stoppers with different foaming states greatly reduce the compression set on the outer periphery, and the foamed part in the center maintains strong elasticity, increasing the compression recovery rate and providing good sealing power for a long period of time. That's what I got.

As explained above, the present invention is an ideal method for manufacturing a synthetic resin wine stopper that is inexpensive, extremely suitable for mass production, and has a strong sealing force.

Claims (1)

[Claims] 1. A method for manufacturing a synthetic resin wine stopper for sealing the mouth of a wine bottle, which involves heating a synthetic resin material mixed with an appropriate amount of an organic foaming agent to a foaming temperature, extrusion molding and cutting, and extrusion molding and cutting. A rod-shaped object is inserted into a mold having a desired diameter and length and which is at least lower temperature than the rod-shaped object, and after the mold is sealed and the pressure is reduced, it is taken out, and the center is highly foamed and the foaming degree decreases toward the outer periphery. A method for manufacturing a synthetic resin wine stopper, characterized in that the outer periphery of the wine stopper is made of a solid layer.