WO2003031276A1

WO2003031276A1 - Method for forming film on cork stopper

Info

Publication number: WO2003031276A1
Application number: PCT/JP2002/010251
Authority: WO
Inventors: Yoji Tanaka
Original assignee: Polymer Systems Co., Ltd.
Priority date: 2001-10-05
Filing date: 2002-10-02
Publication date: 2003-04-17

Abstract

A method for forming a film on a cork stopper, which comprises attaching a synthetic resin powder (31) to an under surface (23) and a peripheral surface (24) of a cork stopper body (2) in an amount necessary for forming one layer of a film, irradiating the powder (31) with a far-infrared radiation emitted by a far-infrared radiation generating device (6), to melt the powder (31), and then solidifying the molten resin, to thereby form a film (not shown) made from the synthetic resin on the under surface (23) and the peripheral surface (24) of the cork stopper body (2); and another method for forming a film on a cork stopper, which comprises sticking a synthetic resin sheet (10) being softened by heating to the under surface (23) and the peripheral surface (24) of the cork stopper body (2) , followed by solidifying it. The methods allow the formation on the outer surface of a cork stopper body (2) of a film made from the synthetic resin with a reduced thickness, at a reduced cost.

Description

Method of forming a coating on a cork stopper

The present invention relates to a method for forming a coating on a cork stopper for forming a synthetic resin coating on the outer surface of a stopper body containing a cork material.

Background art

In recent years, cork stoppers in which a coating made of a synthetic resin is formed on the lower surface and the outer peripheral surface of a stopper body containing a cork material are widely used. This is because, by forming a coating on the plug body, part of the cork material may fall off and be mixed in the beverage contained in the bottle, or the plug body may be degraded by the alcohol contained in the beverage. Because it can prevent

By the way, as a method of forming a coating made of a synthetic resin on the lower surface and the outer peripheral surface of the plug body, for example, it is described in JP-A-5-31851 and JP-A-5-35555. There is the one listed. In these forming methods, first, a bottomed cylindrical synthetic resin container having an open upper end is formed by a pro-forming method. Next, insert the stopper body into this container. Thereafter, the container in which the plug body is inserted is inserted into the molding recess of the mold to heat and melt the container. Thereby, a coating made of a synthetic resin is formed on the lower surface and the outer peripheral surface of the plug body.

In the above conventional method for forming a coating, at least the steps of: blow molding the container, inserting the stopper body into the container, inserting the container and the stopper body into the molding recess of the mold, heating and melting the container Four processes are required, and the manufacturing process is diverse. Therefore, there is a problem that the labor and cost required for forming a film increase. Further, since the container is formed by blow molding, it is difficult to make the thickness of the container thinner than a certain level, and the thickness of the coating becomes relatively thick accordingly. Specifically, it was difficult to reduce the thickness of the coating to less than 0.2 mm. Disclosure of the invention

In order to solve the above problems, in the first invention, when forming a coating made of a synthetic resin on the outer surface of a stopper body containing a cork material, a powder made of a synthetic resin is attached to the outer surface of the stopper body, The powder is heated and melted to form a synthetic resin film on the outer surface of the plug body.

In this case, it is desirable to cause the powder to adhere to the plug body by electrostatic coating.

It is desirable that the above-mentioned powder be heated and melted by irradiating far infrared rays. In order to solve the above problems, according to the second invention, a sheet made of a synthetic resin is placed on the upper surface of a mold having a molded recess formed on the upper surface, and then heated and softened. Vacuum suction to draw a part of the sheet into the molding recess to bring it into close contact with the inner surface thereof, as well as pressing a stopper body containing a cork material into the molding recess through the sheet to lower and outer periphery thereof By bringing the sheet into close contact with the surface, a coating made of a synthetic resin is formed on the lower surface and the outer peripheral surface of the plug body. In this case, it is desirable that the portion of the sheet drawn into the forming recess be heated and melted by the mold.

Forming an annular flange portion horizontally projecting on the upper end portion of the film formed on the outer peripheral surface of the plug body by a portion of the sheet placed on the upper surface of the mold; Is desirable. In the case of forming the flange portion, it is preferable to mold the holding portion made of hard resin in close contact with the upper surface of the plug body and the upper surface of the flange portion by injection molding.

In order to solve the above problems, according to a third aspect of the present invention, a plug main body including a cork material is placed upside down on the center of the bottom of the accommodation recess of the mold in which the accommodation recess is formed on the top surface. After placing a synthetic resin sheet on the upper surface of the mold so as to seal the upper opening of the accommodation recess, heat and soften the sheet, and then open the bottom of the accommodation recess. Forming a film made of synthetic resin on the lower surface and the outer peripheral surface of the plug body by vacuum-suctioning the inside of the accommodation recess from the passage to fix the sheet on the lower surface and the outer peripheral surface of the plug body. And

In this case, the opening of the passage at the bottom surface of the housing recess is: It is desirable to be arrange | positioned adjacent to the outer peripheral surface of the said plug main body fixed on the bottom face. It is desirable that the sheet be pressed and fixed to the upper surface of the mold along the opening of the accommodation recess by a pressing member before vacuum suction in the accommodation recess after heating the sheet. Les.

By vacuum-suctioning the inside of the accommodation recess and bringing the sheet into close contact with the bottom surface of the accommodation recess, from the upper end edge corresponding to the upper end of the closure body among the films adhered to the outer peripheral surface of the closure body It is desirable to form a horizontally projecting annular flange. In the case of forming the flange portion, it is preferable to mold the holding portion made of hard resin in close contact with the upper surface of the upper surface of the flange portion by injection molding. Brief description of the drawings

FIG. 1 is a partially omitted sectional view showing a process of heating and melting a powder in the method of forming a film according to the first invention.

FIG. 2 is a cross-sectional view showing an example of a cork stopper on which a film is formed by the method for forming a film according to the first invention.

FIG. 3 is a cross-sectional view showing another example of the entire cork shell in which the film is formed by the method for forming a film according to the first invention.

FIG. 4 is a schematic block diagram showing the previous step of the film forming step in the embodiment of the second invention.

FIG. 5 is a view similar to FIG. 1 showing a state at the time of the film forming step in the same embodiment.

FIG. 6 is a schematic configuration view showing a holding portion forming process of the embodiment.

FIG. 7 is a cross-sectional view showing a cork stopper on which a film is formed by the method for forming a film according to the second or third invention.

FIG. 8 is a schematic block diagram showing the previous step of the film forming step in the embodiment of the third invention.

FIG. 9 is a view similar to FIG. 5 showing a state in the step of forming a film in the same embodiment. FIG. 10 is a schematic configuration view showing a grip portion forming process of the embodiment. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 10.

FIG. 2 shows an example of a cork stopper on which a film is formed by the forming method according to the first invention. The cork stopper 1 has a main body 2 containing a cork material and a coating 3 made of a synthetic resin.

The plug body 2 is in the form of a bar having a circular cross-section that is long in the vertical direction, and a mounting hole 22 is formed in the center of the upper surface 21 thereof. The mounting hole 22 is for inserting and fixing the lower end portion of the grip portion (see the grip portion indicated by reference numeral 4 in FIG. 7). Therefore, when the grip portion is not attached to the plug body 2, the mounting hole 22 is unnecessary. Further, at the intersection of the lower surface 23 of the plug body 2 and the outer peripheral surface 24, an arc-shaped chamfer 25 having a cross section of a half is formed. The chamfer 25 need not necessarily be formed. The plug body 2 can be manufactured by scraping from cork bark. In this case, the entire plug body 2 is made of cork material. Alternatively, the plug body 2 can be formed by mixing an adhesive with cork particles obtained by grinding cork bark, and applying pressure and heat to this in a mold. Alternatively, when cork particles and an adhesive are pressurized and heated, they have an appropriate thickness as described in the above two publications without directly molding the stopper body 2 thereby. The plug body 2 may be formed by first forming a squeeze body, laminating the squeeze bodies in a necessary amount, and fixing the respective squeeze bodies to each other.

The film 3 is made of a synthetic resin such as polyethylene, polypropylene or polyester, and has a thickness of about 50 to 200 m. Moreover, in this cork stopper 1, the coating 3 is formed on the lower surface (outer surface) 23 and the outer peripheral surface (outer surface) 24 of the stopper body 2, but when the opening of the bottle is closed by the cork stopper 1 Only the lower surface 23 of the stopper body 2 comes in contact with the liquid in the bottle. Therefore, the coating 3 may be formed only on the lower surface 23. Conversely, a coating may be formed not only on the lower surface 23 and the outer peripheral surface 24 but also on the inner surface of the upper surface 21 and the mounting hole 22.

In the case where the coating 3 is formed on the lower surface 23 and the outer peripheral surface 24 of the plug body 2, as shown in FIG. As described above, the powder 31 of the synthetic resin constituting the film 3 is attached to the lower surface 23 and the outer peripheral surface -24 of the plug body 2. At this time, masking for preventing the adhesion of the powder 31 is applied to the upper surface 21 and the inner surface of the mounting hole 22 which do not need to form the film 3. It is desirable that powder 31 have a particle diameter of about 10 to 50 m. Powder 31 can be attached to lower surface 23 and outer peripheral surface 24 by a known injection gun. When depositing powder 31, it is desirable to do as follows to prevent the powder 31 from scattering and deteriorating the working environment.

That is, an adhesion chamber (not shown) shielded from the outside is provided except for the inlet and the outlet. In the adhesion chamber, there is provided a transport means (not shown) for carrying the plug body 2 into the adhesion chamber from the inlet and carrying it out from the outlet. The above-mentioned injection guns are installed on both sides and under the transfer direction of the transfer means. On the other hand, as shown in FIG. 2, the support shaft 5 is inserted into and fixed to the mounting hole 22 of the plug body 2, and the plug body 2 is attached to the conveying means via the support shaft 5. Then, the plug body 2 is transferred by the transfer means into the adhesion chamber. While the plug body 2 is transported from the inlet force of the adhesion chamber to the outlet, the powder 31 sprayed by the injection gun adheres to the lower surface 23 and the outer peripheral surface 24 of the plug body 2. In addition, since the atmosphere in which the powder 31 injected from the spray gun is suspended in a large amount in the adhesion chamber, the floating powder 31 also adheres to the plug body 2. Thereby, the powder powder 31 can be uniformly attached to the lower surface 23 and the outer peripheral surface 24 without any gap. In particular, when the plug body 2 is slowly rotated about the axis of the mounting hole 2 2 (the axis of the plug body 2), the powder 31 can be deposited more uniformly.

As apparent from FIG. 1, the powder 31 only adheres to the lower surface 23 and the outer peripheral surface 24 but does not adhere in a plurality of layers. This is because the powder 31 in contact with the powder 31 adhering to the lower surface 23 and the outer peripheral surface 24 falls off without adhering to the powder 31 on the plug body 2 side. When the powder 31 is to be attached to the lower surface 23 and the outer circumferential surface 24, it is desirable to electrostatically charge the powder 31 in order to increase the adhesion of the powder 31 to the plug body 2. That is, it is desirable that the powder 31 be attached to the plug body 2 by the electrostatic coating method. As a method of charging the powder 31 with electrostatic charge, there is a triboelectric charging method.

Next, the powder 31 adhering to the lower surface 23 and the outer peripheral surface 24 of the plug body 2 is heated and melted. In this case, it is desirable that the heating temperature be as low as possible within the range in which the powder 31 can be melted. This is to prevent the cork material constituting the plug body 2 from being burnt by the heat for melting the powder 31. In order to prevent the burning of the cork material, it is desirable to heat powder 31 by far infrared rays. For example, as shown in FIG. 1, the far infrared radiation generator 6 is installed facing the lower surface 23 and the outer circumferential surface 24 of the plug body 2 respectively, and the far infrared radiation generator 6 Irradiate. It is desirable to use far-infrared radiation in the following heating chamber.

That is, the heating chamber is installed in front of the adhesion chamber in the transport direction of the transport means. In the heating chamber, the plug body 2 to which the powder 31 is attached is carried in from the inlet by the above conveying means and carried out from the outlet. The above-mentioned far-infrared and soot generator 6 is installed on both sides and the lower side of the transport direction of the transport means. Then, while the plug body 2 is transported from the inlet to the outlet in the heating chamber, the powder 31 is heated and melted by the far infrared rays generated by the far infrared ray generator 6. Moreover, the entire heating chamber is in a high temperature atmosphere in which the powder 31 is melted by the far infrared rays emitted by the far infrared ray generator 6. Therefore, the powder 31 adhering to the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 can be uniformly melted without unevenness. In this case, the plug 2 can be melted more uniformly by rotating the plug 2 slowly about its axis. Thereafter, when the plug body 2 is carried out from the outlet of the heating chamber, the molten resin is naturally cooled and solidified by the outside air. Thus, a thin film 3 made of a synthetic resin is formed on the lower surface 23 and the outer peripheral surface 24 of the plug body 2. Moreover, the film 3 is fixed to the lower surface 23 and the outer peripheral surface 24.

In the above forming method, the synthetic resin film 3 is formed on the plug body 2 only by the steps of: attaching the powder 31 to the plug main body # 2; and heating and melting the powder 31. be able to. Therefore, the labor and cost required for forming the cork stopper 1 can be significantly reduced as compared with the conventional forming method requiring at least four steps. Further, since the powder 31 adhering to the plug body 2 is melted and solidified to form the film 3, the thickness of the film 3 can be reduced as compared with the blow molding. When the coating 3 is thin, when the cork stopper 1 is pressed into the mouth of the bottle, the coating 3 formed on the outer peripheral surface 24 of the stopper main body 2 is substantially uniform due to the flexibility of the stopper body 2 including the cork material. Inner circumference of the mouth 0251

It can be pressed into contact with the seven sides, which ensures that the mouth of the bottle can be sealed.

FIG. 3 shows another example of a cork stopper having a film formed by the forming method of the present invention. In this cork stopper 1A, the coating 3 is not formed on the entire outer peripheral surface 24 of the plug body 2, but the coating 3 is annularly formed only on the middle portion of the outer peripheral surface 24 in the longitudinal direction of the plug body 2. It is done. Further, the chamfer 25 is not formed at the intersection of the lower surface 23 and the outer peripheral surface 24 and intersects almost at right angles. The other configuration is the same as that of the above-mentioned cork stopper 1, and the coating 3 can be formed in the same manner as the case of the Konorek stopper 1.

The first invention is not limited to the above embodiment, and can be changed as appropriate. .

For example, in the above embodiment, the powder 31 attached to the plug body 2 is heated and melted, and then solidified to complete the formation of the film 3. However, after the film 3 is solidified, gold The entire plug body 2 is inserted into the molding recess of the mold, and the coating 3 is brought into contact with the inner surface of the recess. Then, the film 3 may be melted again by a mold and then solidified. In addition, a polyester film having a thickness of about 30 m may be fixed to the outer surface of the coating 3 by heat fusion or the like. In this way, it is possible to prevent the smell of the film 3 and in particular the smell of the film 3 made of polyethylene from being introduced into the beverage, and in the case of a cork stopper used for a bottle of an alcohol-rich beverage In this case, the film 3 can be prevented from being denatured by alcohol. Furthermore, a coating 3 and a polyester film are also provided on the upper surface of the plug body 2 and the outer peripheral edge thereof is fixed to the upper end edge of the film 3 and polyester film provided on the outer peripheral surface of the plug You may

Next, embodiments of the second and third inventions will be described.

FIG. 7 shows an example of a cork stopper on which a film is formed by the forming method according to the second or third invention. This cork stopper 1 B differs from the above-described cork stopper 1 in that a coating 3 'is provided instead of the coating 3 and a grip 4 is further provided. Therefore, only the coating 3 'and the grip 4 will be described.

The coating 3 'is formed of the same material as the coating 3 and has the same thickness as the coating 3 doing. The coating 3 'is composed of a coating 32 and a flange 33. The covered portion 32 has a bottom at its lower end, and is formed as a cylinder whose upper end is open. The plug body 2 is inserted into the inside of the covered portion 32. The bottom surface of the covering portion 32 is fixed to the lower surface 23 of the plug body 2. The inner peripheral surface of the covering portion 32 is fixed to the outer peripheral surface of the plug body 2. The flange portion 33 has a circular shape, and the center thereof coincides with the center of the covering portion 32. The upper surface of the flange portion 33 is flush with the upper surface 21 of the plug body 2.

The gripping portion 4 is made of a relatively hard resin, and has a disc-shaped main body 4 1 and a shaft portion 42 projecting from the lower surface central portion of the main body 41. ing. The outer diameter of the main body portion 41 is set to be larger than the outer diameter of the plug main body 2 and equal to the outer diameter of the flange portion 33. The shaft portion 42 is inserted into the mounting hole 22 of the stopper body 2. The lower surface and the outer peripheral surface of the shaft portion 42 are fixed to the inner peripheral surface and the bottom surface of the mounting hole 22 of the plug body 2 respectively. Moreover, the lower surface of the main body 41 is fixed to the upper surface 21 of the plug main body 2. Thereby, the grip 4 is fixed to the plug body 2. A flange portion 33 is fixed to the lower surface of the main body portion 41 protruding from the outer peripheral surface of the plug body 2.

Next, the case of producing the cork stopper 1B of the above-described configuration will be described.

When manufacturing the cork stopper 1 B, first, the coating 3 is formed on the lower surface 23 and the outer peripheral surface 24 of the stopper body 2. At that time, the forming method shown in FIG. 4 and FIG. 5 (the forming method according to the second invention) is adopted. In the method, a lower mold (mold) 7 and an upper mold 8 disposed opposite to each other in the upper and lower sides and a heating means 9 are used.

The lower die 7 has a horizontal upper surface 71, and in the center of the upper surface 71, a molding hole 72 having a circular cross section is formed. The inner diameter of the forming hole 72 is set to be substantially the same as the outer diameter of the covering portion 32. The depth of the forming hole 72 is set to be substantially equal to the length obtained by adding the height of the plug body 2 and the thickness of the covering portion 32 fixed to the lower surface thereof. At the bottom of the formed hole 72, air passages 11, 12 are opened respectively. One air passage 11 is connected to a vacuum tank 14 via an on-off valve 13. The other air passage 12 is connected to a pressurized air supply source 16 via an on-off valve 15.

The upper mold 8 has a shaft 81 at the center of its lower surface. _B The shaft 81 is fitted in the mounting hole 22 of the stopper body 2. The lower end face of 1 is the mounting hole 2 I hit the bottom of 2. The shaft 81 has its axis aligned with the axis of the forming hole 72. Therefore, when the upper mold 8 is moved downward, the plug body 2 gets into the forming hole 7 2. The upper mold 8 is between the standby position shown in FIG. 4 spaced apart from the lower mold 7 and the molding position where the entire plug body 2 attached to the shaft 81 can be inserted into the forming hole 72. Can be moved up and down.

The heating means 9 is fixed in position between the lower die 7 and the upper die 8 located at the standby position in the vertical direction, and is movable in the horizontal direction. The range of movement of the ripening means 9 in the horizontal direction is between the heating position shown in FIG. 4 facing the upper surface 71 of the lower mold 7 and the standby position horizontally spaced from the upper surface 71 of the lower mold 7. is there.

When forming the covering portion 32 on the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 using the lower mold 7, upper mold 8 and heating means 9, the upper mold 8 and the heating means 9 are Keep it in the stand-by position and close the on-off valves 1 3, 1 5. In addition, the plug body 2 is fitted and fixed to the shaft 81 of the upper mold 8.

After preparing in this manner, first, as shown in FIG. 4, a synthetic resin sheet 10 is placed on the upper surface 71 of the lower mold 7. This sheet 10 is for constituting the coating 3 ′. Therefore, the sheet 10 is made of the same material as the film 3 'and has substantially the same thickness as the film 3' and an outer diameter larger than the outer diameter of the flange 33 by a predetermined size. ing. The sheet 10 is placed on the upper surface 71 so that the center of the sheet 10 is located on the axis of the forming hole 7 2.

Next, the heating means 9 is moved to the heating position. Then, the sheet 10 is heated and softened by the heating means 9 to such an extent that the upper surface thereof is slightly melted. At this time, it is desirable that the lower mold 7 be preheated to a temperature slightly lower than the melting temperature of the sheet 10. This heating can be performed, for example, by providing a heating means (not shown) in the lower mold 7. When the heating of the sheet 10 is completed, return the heating means 9 to the standby position.

Next, as shown in FIG. 5, the upper die 8 is moved downward, and the plug body 2 is inserted into the forming hole 72 through the sheet 10. When the lower end of the plug body 2 starts to be inserted into the forming hole 72 through the sheet 10, the on-off valve 13 is opened, and the inside of the forming hole 72 is vacuum suctioned by the vacuum tank 14. Then, by moving the upper mold 8 downward to the forming position, Insert the whole plug body 2 into the forming hole 72 through the sheet 10. Then, the portion of the sheet 10 drawn into the forming hole 72 closely adheres to the inner peripheral surface and the bottom surface of the forming hole 72 and also adheres to the lower surface 23 and the outer peripheral surface 24 of the plug body 2. Thus, the covering portion 32 is formed. Moreover, since the contact surface of the covering portion 32 (sheet 10) with the plug body 2 is melted, the molten portion adheres, whereby the covering portion 32 is the lower surface 23 of the plug body 2 and the outer periphery. Stick to face 24

Thus, in the method of forming the covering portion 32, the sheet 10 is used as the lower mold 7 in the step of forming the covering portion (coating) 32 on the lower surface 23 and the outer peripheral surface 24 of the plug body 2. Three steps are required: placing the sheet 10 on the upper surface 71, heating the sheet 10, and inserting the sheet 10 and the plug body 2 into the forming hole 72 of the lower mold 7. Therefore, the labor and cost required for forming the coating 32 can be reduced as compared with the conventional method for forming a coating which requires four steps. In addition, since the covering portion 32 is formed by the gap between the inner surface of the forming hole 72 and the lower surface 23 and the outer peripheral surface 24 of the plug body 2, the thickness can be reduced. Specifically, according to this formation method, the thickness of the covering portion 32 can be 50 to 200 m. Also, the thickness of each portion of the covering portion 3 2 can be made substantially uniform.

In addition, after inserting the sheet 10 and the main body 2 into the forming hole 72, the lower mold 7 is heated by the heating means provided in the inner portion to form the covering portion 32 of the sheet 10. The covering portion 32 in close contact with the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 may be formed by heating and melting a portion to be hardened and then solidifying.

At the same time as the covering portion 32 is formed, the remaining part which is not drawn into the forming hole 72 of the sheet 10 is a direction perpendicular to this from the upper end of the covering portion 32 by the upper surface 71 of the lower mold 7 It is formed as an annular portion 34 projecting in the (horizontal direction). The outer diameter of the annular portion 3 4 is larger than the outer diameter of the flange portion 33. In other words, the size of the sheet 10 is preset so that the annular portion 34 with a diameter larger than that of the flange 咅 P 33 can be formed.

Thereafter, when the covering portion 32 is sufficiently solidified, the on-off valve 13 is closed, and the on-off valve 15 is opened to introduce high pressure air from the pressurized air supply source 16 to the bottom side of the forming hole 72. At the same time, the upper die 8 is moved upward to the standby position. This makes the plug body 2. Remove the sheet 10 fixed to it from the forming hole 72. After that, remove the stopper body 2 from the shaft 8 1 of the upper mold 8.

Next, the grip portion 4 is formed on the upper surface of the portion of the upper surface 21 of the plug body 2 and the annular portion 34 which is to be the flange portion 33. The grip 4 is formed by injection molding using the lower mold 100 and the upper mold 200 shown in FIG.

A shallow circular recess 102 is formed in the upper surface 101 of the lower mold 100. The recessed portion 102 has a depth substantially the same as the thickness of the annular portion 34 and an inner diameter larger than that of the annular portion 34. An accommodation hole 103 is formed in the center of the bottom of the recess 102. The housing hole 103 has an inner diameter substantially the same as the outer diameter of the covering portion 32 and a depth equal to the distance from the lower surface of the annular portion 34 to the lower surface of the covering portion 32. In addition, a push rod 104 is provided on the lower side of the lower hole 100 of the lower mold 100. The push rod 104 is disposed with its axis aligned with the axis of the receiving hole 103, and is provided so as to be vertically movable. The upper end surface of the push rod 104 is usually flush with the bottom surface of the accommodation hole 103 and constitutes a part of the bottom surface of the accommodation hole 103. The lower end portion of the push rod 104 protrudes downward from the lower mold 100.

The upper mold 200 is arranged to be able to move up and down with respect to the lower mold 100. Of course, the lower mold 100 may be disposed so as to be movable toward and away from the upper mold 200, or both may be moved simultaneously. Alternatively, the upper and lower molds 100 0, 20 0 may be made to face in the horizontal direction, and both may be moved in the horizontal direction. A molding recess 202 is formed on the lower surface 201 opposed to the lower mold 100 of the upper mold 200. The molding recess 202 has the same inner diameter as the outer diameter of the main body portion 41 of the grip portion 4 and the same depth as the height of the main body portion 41. Coaxially arranged. A cutting blade 203 is annularly formed at the intersection of the lower end opening of the forming turn portion 202 and the lower surface 201 so as to surround the forming recess 202. The tip end (lower end) of the cutting blade 203 is substantially in contact with the bottom surface of the ridge portion 102 when the lower surface 201 of the upper mold 200 is butted to the upper surface 101 of the lower mold 100. It is supposed to Therefore, when the upper and lower molds 1 0 0 0 2 0 0 0 0 are brought into contact, the annular portion 3 4 is cut into a circular shape by the cutting blade 2 0 3. And the inside of the annular part 34 cut by the cutting blade 203 The portion on the side is the flange portion 3 3. Further, the upper mold 200 is formed with a passage 204 whose one end is open to the upper bottom surface of the molding recess 202 and the other end is open to the outer surface of the upper mold 200. The passage 204 is for supplying a synthetic resin for molding the grip 4 to the molding recess 202. When injection molding the grip 4 using the lower mold 100 and the upper mold 200 of the above configuration, first insert the main body 2 and the cover 32 into the accommodation hole 103, Place the annular part 3. 4 in the recess 102. Thereafter, lower mold 100 and upper mold 200 are butted against each other. Then, the annular portion 34 is annularly cut by the cutting blade 203, and the flange portion 33 is formed by the portion ^ 1 thereof. Further, a cavity C for forming the grip 4 is formed by the forming recess 202, the upper surface of the flange portion 33, and the upper surface 21 of the plug body 2 and the inner surface of the mounting hole 22. The cavity C is filled with the molten resin for forming the grip 4 from the passage 2 0 4. Then, the main body portion 41 is molded by the molding recess 202, and the shaft portion 42 is molded by the mounting hole 22. The lower surface of the main body 41 adheres to the upper surface 21 of the plug main body 2 and the upper surface of the flange portion 33 when the molten resin solidifies, and the outer peripheral surface and the lower surface of the shaft portion 42 are mounting holes.

2 Stick to the inner surface and bottom of 2.

When the molten resin filled in the cavity C is fully solidified, separate the upper mold 200 from the lower mold 100 upward. Thereafter, the push rod 104 is moved upward to take out the main body 2 and the film 3 ^ from the accommodation hole 103. As a result, a cork stopper 1B comprising the stopper body 2, the membrane 3 and the grip 4 is obtained.

Next, another method of manufacturing the above-mentioned cork stopper 1B will be described. Even in this manufacturing method, in the case of manufacturing the cork stopper 1B, the covering portion 32 is first formed. In forming the covering portion 32, the forming method (the forming method according to the second invention) shown in FIG. 8 and FIG. 9 is adopted. In this forming method, a lower mold (mold) 300, an upper mold (pressing member) 400 and a heating means 500 are used.

The lower die 300 is formed with a housing recess 302 with a circular cross section at the center of the upper surface 301 thereof. The depth of the housing recess 302 is substantially the same as the height of the plug body 2, but may be deeper than the height of the plug body 2. The inside diameter of the housing recess 302 is the flange

The diameter is slightly larger than the outer diameter of 33, and substantially the same as the outer diameter of the annular portion 34 in the above embodiment. — Or slightly larger. A positioning protrusion 303 is formed at the center of the bottom of the housing recess 302. By fitting the mounting hole 22 of the plug body 2 to the positioning protrusion 3 0 3, the plug body 2 is positioned at the central portion of the housing recess 3 0 2. One end of a plurality of passage holes (passages) is opened at the bottom of the housing recess 302. The opening of each passage hole 304 is arranged on a circle centered on the center of the protrusion 3 0 3. In addition, the opening of each passage hole 304 is disposed so that the side facing the inner circumferential side of the circumference is substantially in contact with the outer peripheral surface 24 of the plug main body 2 positioned by the protrusion 33. ing. The other end of each passage hole 304 is connected to either the vacuum tank 18 or the high pressure air supply source 19 via a switching valve 17.

The upper mold 400 has a pressing portion 401 having the same outer diameter as the upper surface 301 of the lower mold 300. The upper die 400 is disposed with the center of the pressing portion 401 aligned with the center of the lower die 300, and is shown in FIG. 8 which is spaced upward from the lower die 300. It is possible to move vertically between the standby position and the forming position in which the lower surface of the pressing portion 401 abuts on the upper surface 3 0 1 of the lower mold 3 0 0 through the sheet 1 0.

The ripening means 500 is disposed between the lower mold 300 and the upper mold 400 in the vertical direction, similarly to the heating means 9 in the above embodiment, It is possible to move horizontally between the mature position.

In the case where the covering portion 32 is formed on the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 using the lower mold 300, the upper mold 400 and the heating means 500, as shown in FIG. Thus, the plug main body 2 is placed upside down and placed on the bottom of the housing recess 302. At this time, the stopper body 2 is positioned by fitting the positioning projection 3 0 3 into the mounting hole 2 2. Next, place the sheet 10 on the upper surface 301 of the lower mold 300 and seal the storage DA unit 302. Thereafter, the heating means 500 is moved to the heating position to heat and soften the sheet 10. When the sheet 10 is sufficiently heated and softened, the heating means 500 is moved to the standby position, while the upper mold 400 is moved downward to the forming position. Then, as shown in FIG. 9, the sheet 10 is annularly held by the lower mold 300 and the upper mold 400. In particular, in this embodiment, since the depth of the housing recess 302 is the same as the height of the plug body 2, the central portion of the sheet 10 is the lower surface 23 of the plug body 2 and the upper mold 40 0 Sandwiched by The central part of sheet 10 does not have to be pinched. Upper and lower types 3 0 0, 4 0 0 The lower mold 300 and upper mold 400 are heated so that the sheet 10 is not cooled by the lower mold 300 and upper mold 400 when the sheet 10 is sandwiched by It is desirable to provide the means and heat them to almost the same temperature as the heating temperature of the sheet 10.

With the upper mold 400 moved to the forming position, the receiving recess 302 is sealed by the sheet 10 and the upper mold 400. In this state, when the switching valve 17 is operated to connect each passage hole 304 to the vacuum tank 18, the inside of the housing recess 302 is vacuum-sucked. Then, a portion of the sheet 10 located between the inner circumferential surface of the housing recess 302 and the lower surface 23 of the plug body 2 is drawn into the housing recess 302 by negative pressure. Then, it is in close contact with the inner peripheral surface and the bottom of the housing recess 302 and also in close contact with the outer peripheral surface 24 of the plug body 2. The central portion of the sheet 10 is in close contact with the lower surface 23 of the plug body 2 by the upper mold 400. After that, the sheet 10 is fully solidified. At this time, the part of the sheet 10 in close contact with the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 adheres to them and becomes the covering portion 32. The part in close contact becomes the annular part 34.

When the covering portion 32 is formed on the lower surface 23 and the outer peripheral surface 24 of the plug main body 2 as described above, the step of inserting the plug main body 2 into the forming hole 72 of the above embodiment is unnecessary. Therefore, the manufacturing cost of cork stopper 1B can be further reduced by that amount. Further, the sheet 10 is stretched substantially as it goes from the lower surface 23 side of the plug body 2 to the upper surface 21 side. Therefore, the covering portion 3 2 formed on the outer peripheral surface 24 of the plug body 2 is thicker on the lower surface 23 side of the plug body 2 and thinner on the upper surface 21 side. Corresponding to this, the outer diameter of the cork stopper 1 B (the outer diameter of the portion where the covering portion 32 is formed) is smaller on the upper surface 21 side of the plug main body 2 and larger on the lower surface 23 side. As a result, when the cork stopper 1 is pressed into the opening of a bottle or the like, there is an advantage that the cork stopper 1 B is less likely to come off the opening. When the sheet 10 is fully solidified, move the upper mold 400 upward to the standby position. Thereafter, the plug main body 2 and the sheet 10 fixed thereto are taken out from the accommodation recess 302 upward. At this time, the switching valve 17 is operated to connect the high pressure air supply source 1 9 to each passage hole 3 0 4, and the high pressure air is supplied to the accommodation recess 3 0 2. As a result, the plug body 2 and the sheet 10 can be easily removed from the receiving recess 302. Next, the grip 4 is formed on the upper surface of the portion of the upper surface 21 and the annular portion 34 of the plug body 2 which should be the flange portion 33. The grip 4 is molded by injection molding as in the above embodiment. However, in this case, the cylindrical portion 35 projecting downward from the outer peripheral edge of the annular portion 34 in the sheet 10 is formed by the inner peripheral surface of the accommodation recess 30 2 simultaneously with the formation of the covering portion 32. Therefore, in place of the lower mold 100 and the upper mold 200 in the above embodiment, the lower mold 100 0 ′ and the upper mold 200 0 ′ shown in FIG. 10 are used. The outer diameter of the lower mold 100 ′ is slightly smaller than the inner diameter of the cylindrical portion 35. In addition, an annular portion 34 is placed on the upper surface 101 of the lower die 1 00 0, and the upper die 2 0 0 0 abuts against the lower die 1 00 via the annular portion 34. It is done. The other configuration is the same as that of the above-described embodiment, so the same reference numerals are given to the same parts and the description thereof is omitted.

The present invention is not limited to the above embodiment, and can be modified as appropriate.

For example, in each of the above-described embodiments, since the plug body 2 is provided with the grip portion 4, the method of forming a film according to the present invention is adopted as part of a method of manufacturing a cork stopper. When 4 is not provided, it is adopted as a sole method only for forming a coating on the lower surface 23 and the outer peripheral surface 24 of the plug body 2.

Further, in each of the above embodiments, when the lower mold 10 0, 1 0 0 0 0 and the upper mold 2 0 0 0, 2 0 0 0 for forming the holding portion 4 are butted, the annular portion 3 Although 4 is cut to form the flange portion 33, the annular portion 34 may be cut immediately after the formation of the covering portion 32 and the annular portion 34, or after the grip portion 4 is formed. The annular portion 34 may be cut.

Further, when the plug body 2 is not provided with the grip portion 4 to the upper surface of the plug body 2 may be provided with a similar coating with coating 3 ^7. Further, for the reason described above, a polyester film having a thickness of about 30 m may be fixed to the outer surface of the coating 3 'and the coating provided on the upper surface of the plug body 2 by heat fusion or the like. Industrial Applicability

A method of forming a film in a cork according to the present invention comprises: It is useful as a method for forming a coating on the outer peripheral surface and the lower surface of a cork stopper for sealing a container. In particular, to form a coating without compromising the elasticity of the cork stopper body: して and ヽ.

Claims

The scope of the claims

1. When forming a coating made of a synthetic resin on the outer surface of the stopper body containing a cork material, a powder made of a synthetic resin is attached to the outer surface of the stopper body, and this powder is heated and melted to form the outer surface of the stopper body. A method of forming a film on a cork stopper characterized in that a film made of a synthetic resin is formed.

2. The method for forming a coating on a cork stopper according to claim 1, wherein the powder is attached to the stopper body by electrostatic coating.

3. The method for forming a coating on a cork stopper according to claim 1 or 2, wherein the powder is heated and melted by irradiation of far infrared radiation.

4. Place a sheet made of synthetic resin on the upper surface of the mold with the forming recess formed on the upper surface and heat soften, then vacuum suction the inside of the forming recess to partially cover the sheet. The plug is inserted into the molding recess and brought into close contact with the inner surface thereof, and the plug body including the cork material is pushed into the molding recess through the sheet to bring the sheet into close contact with the lower surface and outer peripheral surface thereof. A method of forming a coating on a cork stopper, comprising forming a synthetic resin coating on the lower surface and the outer peripheral surface of the main body.

5. The method for forming a coating on a cork stopper according to claim 4, wherein a portion of the sheet drawn into the forming recess is heated and melted by the mold.

6. An annular flange projecting horizontally at the upper end of the film formed on the outer peripheral surface of the plug body is integrally formed with the film by the portion of the sheet placed on the upper surface of the mold. A method for forming a coating on a cork stopper according to claim 4 or 5,

7. Place the plug main body containing cork material upside down on the center of the bottom of the accommodation recess of the mold in which the accommodation recess is formed on the upper surface, and then place a synthetic resin sheet on the upper surface of the die. After placing the sheet so as to seal the upper end opening of the accommodation recess, the sheet is heated and softened, and then the inside of the accommodation recess is vacuum suctioned from the passage opened at the bottom surface of the accommodation recess. A method of forming a coating film on a cork stopper characterized in that a coating made of a synthetic resin is formed on the lower surface and the outer peripheral surface of the plug main body by fixing the lower surface and the outer peripheral surface of the plug main body.

8. The opening of the passage at the bottom of the receiving recess is disposed adjacent to the outer peripheral surface of the plug main body located at the bottom of the receiving recess. Method of forming a coating on a cork stopper.

9. After heat softening the sheet, before vacuum suctioning the inside of the housing recess, pressing and fixing the sheet on the upper surface of the mold along the opening of the housing recess by a pressing member A method of forming a coating on a cork according to claim 7 or 8, characterized in that.

1 0 By vacuum suctioning the inside of the accommodation recess and bringing the sheet into close contact with the bottom surface of the accommodation recess, the upper end corresponding to the upper end of the plug body among the films adhered to the outer peripheral surface of the plug body The method for forming a coating on a cork stopper according to any one of claims 7 to 9, wherein an annular flange portion which protrudes horizontally from an edge is formed.

1 1. The injection molding method is used to mold the holding portion made of hard resin in close contact with the upper surface of the plug body and the upper surface of the flange portion. Method of forming a coating on a cork stopper.