JPH08175554A - Rubber stopper, and manufacture thereof - Google Patents

Abstract

PURPOSE: To manufacture a laminated rubber stopper for medicinal use that is excellent in tightness in fitting while being hard for separation of film by a method wherein the rubber stopper, with its leg and flange covered with film that is inactive to a medical fluid, is formed by one-time molding, using upper and lower molds. CONSTITUTION: A first film sheet 13, inactive to a medical fluid, is laid on a lower mold 10 having a recession for forming a leg part, and an unvulcanized rubber sheet 14 and a second film sheet 15 are layered on the first film sheet, and heating and pressurization are applied with an upper mold 11 having an tapered part 17a, and thereby a rubber stopper element is made by punching. The rubber stopper element is supported with a cylindrical member and horizontal cutting is made, starting from the middle on a corner 2d of a flange toward the upper end of the cylindrical member, and thereby rubber is exposed on a part between the corner 2d and a recessed part 6. As the flange is covered with a film 4, starting from the top face 2b and ending up at the corner 2d and the covering is contracted at the corner 2d, the film is hardly separated at its end. As the rubber is exposed to the face 2c contacting the mouth of a bottle and the ring-like recessed part 6 is formed to the face 2c, tightness in sealing can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber stopper for sealing, for example, a vial for sealing a chemical solution, and more particularly to a rubber stopper having a surface laminated with a film or the like so as not to affect the chemical solution.

[0002]

2. Description of the Related Art Conventionally, as a rubber stopper used in a vial for filling a chemical solution, one using butyl rubber is well known. However, as a method of laminating a film to prevent elution of vulcanization accelerators and curing agents of butyl rubber, there are those disclosed in Japanese Examined Patent Publication No. 2-40491 or Japanese Utility Model Laid-Open No. 58-29939. .

Japanese Examined Patent Publication No. 2-40491 was issued on June 6, 1982.
The present invention was filed on March 30, and relates to a laminated rubber stopper for medical use and a manufacturing method thereof. In this patent publication, the entire surface of the leg of the rubber stopper body consisting of the leg and the flange and the lower surface of the flange are covered with a copolymer film containing tetrafluoroethylene and ethylene as main components, and the material of the rubber stopper is butyl rubber, It is composed of ethylene propylene terpolymer, epichlorohydrin rubber, isoprene rubber, butadiene rubber, and styrene butadiene rubber alone or as a composite with a crosslinked rubber material. The shape of this rubber plug is set to have a ratio of 1 / d in the range of 0.1 to 1.0 when the diameter of the leg is d and the length of the leg from the bottom surface of the flange is l. It is characterized by the rubber stopper. This l / d ratio is well known and is
Although it is based on the British and German industrial standards, it can be formed by using TEF / E film.

Japanese Patent Application Laid-Open No. 58-29939 was filed on August 24, 1981, and was published on February 26, 1983, and the outer circumference of the contact surface of the rubber stopper body with the upper end of the container mouth. The entire leg portion except the portion is laminated with resin, one protruding or groove ring is formed on the rubber surface of the outer peripheral portion of the contact surface, and the inner portion of the ring is covered with resin.

The idea of covering a rubber plug with a resin film is described in Japanese Examined Patent Publication Nos. 52-1355 and 54-911.
The disclosed and proposed resins such as No. 9 include T
There are FE, PCTFE, PE, PP, PVDF and the like.

[0006]

However, the film-laminated leg portion and the flange portion are separately manufactured in a semi-vulcanized state, and then the both are again put in a mold for secondary molding to be completely bonded. In this case, various stains remain on the upper surface of the leg. For example, when punching out the leg from the rubber sheet formed in the primary molding, when conveying a vulcanized rubber sheet, when cutting with a cutter, when sucking with air and mounting it on the aligner, Further, in the process of setting the element body from the aligning machine to the lower die for the secondary process, the manufacturing oil of the machine, the release agent or the stain of the operator's hand, the dust in the work place, etc. Dirt adhering to the upper surface of these legs must be cleaned.

However, it is difficult to remove the dirt from the upper surface of the leg. Therefore, if the legs and the top surface of the flange are joined together while the cleaning is incomplete, the tip of the needle inserted from the top surface may be contaminated by dirt on the joined portion. Further, in the case of a rubber plug having a resin film adhered to the surface of the leg portion, a gap is easily formed between the end portion of the resin film and the rubber, and there is a problem that the cleaning liquid stays in this gap.

Further, when a resin film is attached to the lower surface of the rubber stopper, tetrafluoroethylene (TFE) is inactive, so that it is not easily attached to butyl rubber. Therefore, a coupling agent is blended with butyl rubber to bond TFE and butyl rubber, but the bonding strength is not sufficient.

Since a large number of rubber plugs are formed on the vulcanized rubber sheet, they are punched out and taken out. However, the bonding force between butyl rubber and TFE is weak, and the punch blade Peeling from the rubber easily occurs at the end of TFE due to the shearing force.

When peeling occurs at the end of this TFE, TF
There is a problem that the cleaning liquid for the rubber plug that has entered the gap between E and the rubber does not easily flow out due to surface tension.

In Japanese Utility Model Laid-Open No. 58-29939, the end portion of the laminate resin is inside the ring-shaped concave or convex portion on the contact surface of the flange, but the end portion of the laminate is in the middle of the contact surface of the flange by any method. It is not disclosed whether to stop in part.

Further, if the contact surface of the flange and the entire surface of the leg portion are covered with a resin film, there is a problem that the sealing performance is deteriorated as compared with the close contact between rubber and glass.

The rubber plug according to the present invention was created in view of such a situation, and various stains do not remain on the top surface of the leg or the gap between the films, and the virgin property of the top surface is secured. By doing so, there is no contamination of the needle tip, avoiding contact between rubber and chemical liquid, preventing alteration of chemical liquid, and high sealing performance.
Another object of the present invention is to provide a rubber stopper which has few molds and processing steps and is advantageous for mass production.

[0014]

In order to solve the above-mentioned problems, the rubber stopper according to claim 1 of the present invention has a brim portion that abuts on the upper end surface of the bottle mouth and a bottle mouth that projects from the lower surface of the brim portion. Is a rubber plug comprising a leg portion press-fitted inside, and a chamfered corner formed by a side peripheral surface of the brim portion and a bottle mouth contact surface contacting an upper end surface of the bottle mouth. The first film layer that is inactive to the chemical is formed from the top surface of the brim to the side peripheral surface and the chamfered corner, and surrounds the root of the leg on the bottle mouth contact surface of the brim. An annular recess is formed, a second film layer inactive to the chemical is formed between the inner wall surface of the recess and the surface of the leg, and the end portion of the first film layer and the end portion of the second film layer are formed. It is characterized in that a rubber surface is exposed at a bottle mouth contact surface located between the portion and the portion.

The rubber stopper according to claim 2 of the present invention is a rubber comprising a brim portion that abuts on the upper end surface of the bottle mouth, and a leg portion that projects from the lower surface of the brim portion and is press-fitted into the bottle mouth. The stopper is chamfered at a corner portion formed by a side peripheral surface of the brim portion and a bottle mouth contact surface which comes into contact with an upper end surface of the bottle mouth, and a side portion from a top surface portion of the brim portion. The first coat layer which is inert to the chemical is formed over the peripheral surface and the chamfered corner, and an annular recess surrounding the root of the leg is formed on the bottle mouth contact surface of the brim, and the inner wall surface of this recess A second coat layer that is inert to the chemical solution is formed between the end of the first coat layer and the end of the second coat layer, and the bottle mouth contact surface is located between the end of the first coat layer and the end of the second coat layer. The feature is that the rubber surface is exposed.

A rubber stopper according to a third aspect of the present invention is the rubber stopper according to the first aspect, characterized in that the recess is provided with a seal ring.

According to the method for producing a rubber stopper of the present invention, a first film inert to the encapsulating liquid chemical is laid in a lower mold having recesses for forming legs, and an unvulcanized rubber sheet is placed on the first film. And laying on the unvulcanized rubber sheet a second film which is inert to the encapsulating chemical, and facing the concave portion for forming the leg portion above the second film, a concave portion for forming the brim portion. An upper mold having a plurality of sheets is formed, and the upper mold and the lower mold are heated and pressed to form a multi-formed sheet of a rubber plug element, and the multi-formed sheet of the rubber plug element is punched out to form a rubber plug. A method of manufacturing a rubber plug, wherein a recess having a diameter corresponding to the outer diameter of the flange is formed in the lower mold, and the periphery of the recess is chamfered, and a leg recess is formed at the center of the recess. And a ring-shaped convex portion surrounding the leg concave portion is formed around the leg concave portion. Using things, after punching step of a number forming sheet of the rubber Senmototai, the ring recess formed in the bottle mouth contact surface of the rubber Senmototai by the ring-shaped convex portion,
While inserting a cylindrical member of the same size as this ring recess,
The rubber plug element is held by the tubular member and the member that supports the top surface of the brim, and is located at a position shallower than the bottom of the ring recess and from the middle of the chamfered corner of the side of the brim. It is characterized in that a rubber surface is exposed between the chamfered corner portion and the ring recessed portion by horizontally cutting the tip end portion of the tubular member.

[0018]

[Operation] According to the rubber plug of claim 1, since the leg portion and the brim portion can be formed by one-time molding, there is no possibility of enclosing various dirts inside, and the virgin property of the rubber is secured. No contamination of the needle tip. Moreover, since the top surface of the brim is covered with the first film layer, even if it gets dirty,
Since it can be easily washed with the film layer, no dirt remains.

Further, the corner portion between the brim portion and the bottle mouth contact surface is chamfered, and the first film layer covers from the top surface portion of the brim portion to the end of the bottle mouth contact surface including the corner portion. Since the end portion of the first film layer has a shape that is narrower than the side surface of the brim portion at the chamfered corner portion, it is difficult for the end portion of the first film layer to peel off from the rubber.

Furthermore, since the end portion of the second film layer covers the inner wall surface of the ring-shaped recess on the bottle mouth contact surface and is rolled into a tubular shape, the strength is improved and the inside of the ring-shaped recess is improved. It is hard to peel off because it is in.

In this way, no cleaning liquid remains in the film gap. Further, the second film layer on the surface of the leg portion prevents contact between the rubber and the chemical liquid to prevent the chemical liquid from deteriorating, has a high sealing property, and is advantageous in mass production because of less molds and processing steps.

At the bottle mouth contact surface, the rubber surface is exposed between the end portion of the first film layer and the end portion of the second film layer, that is, between the ring-shaped recess and the chamfered corner, and the ring-shaped recess is formed. Since it is formed, the caulking force with the aluminum metal etc. is difficult to disperse to the leg side, so the bottle mouth contact surface firmly adheres to the bottle mouth. Therefore, the sealing function is improved by making close contact with the upper end of the bottle mouth such as glass.

According to the rubber stopper of the second aspect, since the rubber surface is covered with the coat layer instead of the film, the same effect as the rubber stopper covered with the film can be obtained.

According to the rubber plug of the third aspect, since the seal ring is provided in the ring-shaped recess, the end portion of the second film layer is more difficult to peel off and the sealing property of the upper end surface of the bottle mouth is further improved. To do.

According to the method of manufacturing the rubber stopper of the fourth aspect, since the bottom of the ring-shaped recess is held by the tubular member, the vicinity of the bottom of the recess on the bottle mouth contact surface is reached from the middle of the chamfered corner of the brim. The first film layer, the rubber, and the second film layer can be reliably cut even when cut horizontally toward, and the end portions of the first and second film layers are not peeled off. In addition, the leg side of the bottle mouth contact surface is covered with the second film layer, and the top and side surfaces of the brim and the corners are covered with the first film layer,
Since the rubber is exposed between the corner and the ring-shaped recess, the sealing performance is improved. In particular, since the ring-shaped recess is formed, the force of caulking the bottle mouth with aluminum metal or the like is difficult to distribute to the leg side, so the bottle mouth contact surface firmly adheres to the bottle mouth. Therefore, the sealing function is improved by making close contact with the upper end of the bottle mouth such as glass.

Further, since the brim portion and the leg portion are integrally formed, and the portion from the middle of the corner portion of the rubber stopper body to the bottom portion of the ring-shaped recess is cut horizontally, the laminated film for preventing contamination of the injection needle is formed. The position can be stopped properly at the middle of the flange. Since the second film layer covers between the ring-shaped concave portion and the leg portion, there is no portion where the chemical solution contacts the rubber. Such a safe laminated rubber stopper for medical use can be mass-produced.

In order to produce a conventional laminated rubber stopper for medicine, an upper mold and a lower mold for primary molding and an upper mold and a lower mold for secondary molding are required, and a rubber molding machine is also used. Although two machines were required, according to the present invention, since a mold for primary molding is required, it is simpler and less labor intensive than before, the manufacturing cost can be reduced, and the mass production efficiency is good.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A rubber stopper and a method for manufacturing a rubber stopper according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a cross-sectional structure of a rubber plug according to an embodiment of the present invention, and reference numeral 1 indicates the entire rubber plug. This rubber stopper 1 has a brim portion 2 and a leg portion 3. In this embodiment, the brim portion 2 and the leg portion 3 are formed mainly of butyl rubber. The rubber that constitutes this rubber stopper is chlorobutyl rubber 1 manufactured by Bayer Japan Ltd.
066 100 parts, Nippon Silica white carbon 30 parts, zinc white 3 parts, magnesium oxide 5 parts, titanium oxide 3 parts, stearic acid 1 part, organosilane 0.5.
Part, AC polyethylene 2 parts, and dipentamethylene thiuram tetrasulfide 1.5 parts. The vulcanization temperature is 160 ° C to 180 ° C, and the vulcanization time is 5 minutes to 8 minutes. Other rubbers include, for example, 100 parts of chlorobutyl 1066 and 9 parts of calcined clay.
0 parts, AC polyethylene 617A 2 parts, stearic acid 1 part, zinc white 5 parts, ZnEDC or ZnBDC 0.5 parts, silane coupling agent (Toray
Dow Corning Silicone Co., Ltd.). When the vulcanization conditions are 380 ° C and 5 minutes, the Shore hardness A is 4
1,100% tensile stress is 11 Kg / cm ² , tensile strength is 96 Kg / cm ² , and elongation is 780%.

The side peripheral surface 2a and the top surface portion 2b of the brim portion 2 are covered with a film 4. The film 4 is fixed to the side peripheral surface 2a and the top surface portion 2b to form a first film layer. The surface of the leg portion 3 is also covered with the film 5.
The film 5 is fixed to the rubber agent of the leg portion 3 and forms a second film layer.

The sheets of the films 4 and 5 forming the first film layer and the second film layer are copolymers of tetrafluoroethylene and ethylene and are inert to the chemical liquid. As the copolymer of tetrafluoroethylene and ethylene, for example, the trade name "Aflex" manufactured by Asahi Glass Co., Ltd. is used. Since the copolymer of tetrafluoroethylene and ethylene contains the above-mentioned silane coupling agent in the rubber material, it is easily bonded to the surface of the rubber stopper and sufficiently fixed.

The corner portion 2d formed by the side peripheral surface 2a of the brim portion 2 and the bottle mouth contact surface 2c that contacts the upper end surface of the bottle mouth is chamfered, and the chamfered corner portion 2d is a film. Covered with 4. The corner portion 2d and the end portion of the film 4 are fixed to each other without a gap by a manufacturing method described later. On the bottle mouth contact surface 2c of the brim portion 2, a ring-shaped recess 6 that surrounds the leg portion 3 is formed. The ring-shaped recess 6 is formed at a position radially outward of the inner diameter portion of the bottle mouth, and slightly outside the projected position of the most bulged portion of the outer peripheral surface of the leg 3. ing. The ring-shaped recess 6 has a rectangular cross section in this embodiment. The inner wall surface of the ring-shaped recess 6 is covered with the film 5.

A seal ring 7 having a circular cross section is held in the ring-shaped recess 6. The seal ring 7 is made of a material such as silicone rubber, butyl rubber, urethane rubber, butadiene rubber, polyethylene, tetrafluoroethylene, or tetrafluoroethylene / ethylene copolymer, which has a particularly high elastic modulus and is soft.

The rubber surface of the bottle mouth contact surface 2c between the corner 2d and the ring-shaped recess 6 is exposed, and the adhesion with the bottle is improved.

According to this rubber stopper 1, the lamination of the films 4 and 5 prevents contact between the rubber and the chemical liquid, and does not cause peeling of the rubber and the films 4 and 5 at the end portions of the films 4 and 5. In addition, the tightness of the bottle can be improved. For example, in the rubber stopper 1, a corner 2d between the brim 2 and the bottle mouth contact surface 2c is chamfered, and a film is formed from the top surface of the brim 2 to the end of the bottle mouth contact surface 2c including the corner 2d. Since the end portion of the film 4 is covered with the groove 4 and has a recessed shape in the chamfered corner portion 2d more than the side surface portion of the brim portion, the end portion of the film 4 is difficult to be peeled from the rubber of the corner portion 2d.

The end of the film 5 is the bottle mouth contact surface 2
Since it covers the inner wall surface of the ring-shaped recess 6 of c and is rolled into a tubular shape, the strength of the end portion of the film 5 is improved, and since it is inside the ring-shaped recess 6, it is difficult to receive an external force. Hard to peel off. At the bottle mouth contact surface 2c, a rubber surface is exposed between the end of the film 4 and the end of the film 5, and between the ring-shaped recess 6 and the chamfered corner 2d.
Furthermore, since the ring-shaped recess 6 is formed, as shown in FIG. 5, the caulking force with the aluminum metal 8 or the like is difficult to disperse on the leg side, so that the bottle mouth contact surface 2c is firmly attached. Stick to mouth 9. Therefore, the sealing function is improved by making close contact with the upper end of the bottle mouth such as glass.

Although the films 4 and 5 are used in the above embodiment, the same effect can be obtained by applying an inert resin such as fluororubber as a coat layer by means of coating or the like.

Next, a method for manufacturing the rubber stopper according to the embodiment of the present invention will be described.

2 to 4 show a method for manufacturing the rubber plug of this embodiment, in which 10 is a lower mold and 11 is an upper mold. The method of manufacturing this rubber plug is as follows. First, the recess 1 for forming the leg is formed.
The first film sheet 13 inert to the encapsulating chemical is laid on the lower mold 10 having 2, and the unvulcanized rubber sheet 14 is laid on the first film sheet 13 and the unvulcanized rubber sheet 14 A second film sheet 15 which is inert to the enclosed drug solution is laid on top.

The material of the unvulcanized rubber sheet 14 is mainly composed of butyl rubber in this embodiment. The rubber of the examples is 100 parts of chlorobutyl rubber 1066 manufactured by Bayer Japan KK, 30 parts of white carbon manufactured by Nippon Silica, 3 parts of zinc white, 5 parts of magnesium oxide, 3 parts of titanium oxide, 1 part of stearic acid, and organo. It is composed of 0.5 part of silane, 2 parts of AC polyethylene, and 1.5 parts of dipentamethylene thiuram tetrasulfide. The vulcanization temperature is 160 ° C to 180 ° C, and the vulcanization time is 5 to 8 minutes. In addition, in other experimental examples, the rubber constituting the rubber stopper is chlorobutyl 106
6 is 100 parts, calcined clay is 90 parts, AC polyethylene 617A is 2 parts, stearic acid is 1 part, zinc white 5 parts, Z
Add 0.5 parts of nEDC or ZnBDC and add a silane coupling agent (manufactured by Toray Dow Corning Silicone Co., Ltd.). The vulcanization condition was 380 ° C for 5 minutes, the Shore hardness A was 41, and the 100% tensile stress was 11 kg.
/ Cm ² , tensile strength 96 kg / cm ² , elongation 780
%.

The first film sheet 13 and the second film sheet 15 are copolymers of tetrafluoroethylene and ethylene and are inert to the chemical liquid. As the copolymer of tetrafluoroethylene and ethylene, for example, the trade name "Aflex" manufactured by Asahi Glass Co., Ltd. is used. The copolymer of tetrafluoroethylene and ethylene is
Since the above-mentioned silane coupling agent is mixed in the rubber material, it is easily bonded to the surface of the rubber stopper and is firmly fixed.

The recess 12 of the lower die 10 is a ring-shaped projection that forms a taper portion 12a and a ring-shaped recess 6 that form part of the corner 2d so as to form the lower portion of the corner 2d of the brim 2. And part 16. Plane 12b of recess 12
Is formed deeper than the position of the bottle mouth contact surface 2c. This is for removing the portion formed by the flat portion 12b by the cutter 20 as described later.

An upper die 11 is arranged above the second film sheet 15. The upper mold 11 is formed with a recess 17 facing the recess 12 and forming the brim 2. A taper portion 17a that forms an upper portion of the corner portion 2d of the brim portion 2 is formed around the concave portion 17 so that the first film sheet 13 can be easily removed from the concave portion 17. The taper portions 17a and 12a are aligned with each other to form the corner portion 2d.
To form.

When the first film sheet 13, the unvulcanized rubber sheet 14 and the second film sheet 15 are arranged between the upper mold 11 and the lower mold 10, the standard of the unvulcanized rubber sheet 14 is satisfied. It is heated and pressed at a known predetermined temperature and pressure. As a result, as shown in FIG. 3, a rubber plug element sheet 18 having a large number of rubber plug elements is formed. A large number of rubber stoppers 1 are connected to the rubber stopper body sheet 18.

To separate the rubber plug 1 from the rubber plug element sheet 18, punching is performed using a punch. At this time, since the corner portion 2d is located inside the side peripheral surface 2a of the brim portion 2, the cutting edge of the punch separates from the corner portion 2d and cuts at the position of the alternate long and short dash line 19 in FIG. In 2d, the films 13 and 15 do not separate from the rubber.

After punching the rubber plug element at the position of the one-dot chain line 19 with the punch, the rubber plug element 2 is cut by the cutter 20.
Cut the side of 1. Before this cutting step, as shown in FIG. 4, the rubber plug element body 21 is placed on the cylindrical jig 22, and the top surface portion of the brim portion 2 is held by suction means such as a suction pad 23 for sucking air. . The diameter of the tip of the tubular member 22 is set to be equal to the diameter of the ring-shaped recess 6. After the rubber plug element body 21 is fixed by the suction pad 23 and the cylindrical jig 22, the suction pad 23 is rotated by the line 24 passing through the central portion of the rubber plug element body 21. In this rotating state, the cutter 20 is attached to the rubber stopper element 2
When entering the position of the bottle mouth contact surface 2c of the corner 2d of 1,
Since the brim portion 2 is thick, it is cut at the position of the bottle mouth contact surface 2c. At this time, since the tubular jig 22 is contained in the ring-shaped recess 6, the force applied from the cutting edge of the cutter 20 is received by the tubular jig 22, so that a clean cut surface is formed on the bottle mouth contact surface 2c. The rubber surface is exposed. In addition, around the rubber plug body 21, the first film sheet 13,
Since the thin portions of the unvulcanized rubber sheet 14 and the second film sheet 15 are cut, the first film sheet 13, the unvulcanized rubber sheet 14, and the second film sheet 15 are cut.
Does not separate from the wall surface of the corner 2d and the inner wall of the ring-shaped recess 6.

[0047]

According to the rubber plug of the first aspect of the present invention, since each part and the brim can be molded by one molding, there is no possibility of entrapping various dirts inside and the virgin property of the rubber is secured. There is no contamination of the needle tip. Also, since the top surface of the brim is covered with the first film layer, even if it gets dirty, it can be easily washed with the first film layer.
No dirt will remain.

Further, the corner portion between the brim portion and the bottle mouth contact surface is chamfered, and the first film layer covers from the top surface portion of the brim portion to the end of the bottle mouth contact surface including the corner portion. Since the end portion of the first film layer has a shape that is narrower than the side surface of the brim portion at the chamfered corner portion, it is difficult for the end portion of the first film layer to peel off from the rubber.

Furthermore, since the end portion of the second film layer covers the inner wall surface of the ring-shaped recess on the bottle mouth contact surface and is rolled into a tubular shape, the strength is improved and the inside of the ring-shaped recess is improved. It is hard to peel off because it is in.

As described above, no cleaning liquid remains in the gap between the films. Further, the second film layer on the surface of the leg portion prevents contact between the rubber and the chemical liquid to prevent the chemical liquid from deteriorating, has a high sealing property, and is advantageous in mass production because of less molds and processing steps.

At the bottle mouth contact surface, the rubber surface is exposed between the end portion of the first film layer and the end portion of the second film layer, that is, between the ring-shaped recess and the chamfered corner, and the ring-shaped recess is formed. Since it is formed, the caulking force with the aluminum metal etc. is difficult to disperse to the leg side, so the bottle mouth contact surface firmly adheres to the bottle mouth. Therefore, the sealing function is improved by making close contact with the upper end of the bottle mouth such as glass. In addition, since the second film layer on the surface of the leg portion slides well in the rubber stopper aligning feeder for capping the vial, there is no chance of being touched manually by the rubber stopper aligning feeder to release it. ， The possibility of contamination can be further reduced, and the plugging work time can be shortened.

According to the rubber plug of the second aspect, since the rubber surface is covered with the coat layer instead of the film, the same effect as the rubber plug covered with the film can be obtained.

According to the rubber stopper of the third aspect, since the seal ring is provided in the ring-shaped recess, the end portion of the second film layer becomes more difficult to peel off, and the sealing property of the upper end face of the bottle mouth is further improved. To do.

According to the method for producing a rubber stopper of claim 4, since the bottom of the ring-shaped recess is held by the tubular member, the vicinity of the bottom of the recess on the bottle mouth contacting surface is reached from the middle of the chamfered corner of the brim. The first film layer, the rubber, and the second film layer can be reliably cut even when cut horizontally toward, and the end portions of the first and second film layers are not peeled off. In addition, the leg side of the bottle mouth contact surface is covered with the second film layer, and the top and side surfaces of the brim and the corners are covered with the first film layer,
Since the rubber is exposed between the corner and the ring-shaped recess, the sealing performance is improved. In particular, since the ring-shaped recess is formed, the force of caulking the bottle mouth with aluminum metal or the like is difficult to distribute to the leg side, so the bottle mouth contact surface firmly adheres to the bottle mouth. Therefore, the sealing function is improved by making close contact with the upper end of the bottle mouth such as glass.

Further, since the brim portion and the leg portion are integrally formed, and the portion from the middle of the corner portion of the rubber stopper body to the bottom portion of the ring-shaped recess is cut horizontally, the laminated film for preventing contamination of the injection needle is formed. The position can be stopped properly at the middle of the flange. Since the second film layer covers between the ring-shaped concave portion and the leg portion, there is no portion where the chemical solution contacts the rubber. Such a safe laminated rubber stopper for medical use can be mass-produced.

In order to produce a conventional laminated rubber stopper for medicine, an upper mold and a lower mold for primary molding and an upper mold and a lower mold for secondary molding are required, and a rubber molding machine is also used. Although two machines were required, according to the present invention, since a mold for primary molding is required, it is simpler and less labor intensive than before, the manufacturing cost can be reduced, and the mass production efficiency is good.

[Brief description of drawings]

FIG. 1 is a sectional view of a rubber plug according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state in which first and second films and an unvulcanized rubber sheet are arranged between a lower mold and an upper mold of the rubber plug of this embodiment.

3 is a cross-sectional view of the upper mold and the lower mold of FIG. 2 in a state of being heated and pressed.

FIG. 4 is a cross-sectional view showing a state in which the rubber plug element is cut.

FIG. 5 is a cross-sectional view of the rubber stopper of the present embodiment mounted on a bottle and fixed with an aluminum plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Rubber stopper 2 ... Collar portion 2a ... Side peripheral surface of the collar portion 2b ... Top surface portion of the collar portion 2c ... Bottle mouth contact surface of the collar portion 2d ... Corner portion of the collar portion 3 ... Leg portion 4 ... Film 5 ... Film 6 ... Ring-shaped recess 7 ... Seal ring

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yuichi Hiraizumi Inventor Yuichi Hiraizumi 4-2-22 Higashiyotsugi, Katsushika-ku, Tokyo Kazusa Hard Chrome Co., Ltd.

Claims (4)

[Claims] 1. A rubber stopper comprising a brim portion that comes into contact with an upper end surface of a bottle mouth, and a leg portion that projects from a lower surface of the brim portion and is press-fitted into the bottle mouth, the side portion of the brim portion. The corner portion formed by the peripheral surface and the bottle mouth contact surface that contacts the upper end surface of the bottle mouth is chamfered, and the chemical solution is applied from the top surface portion of the brim portion to the side peripheral surface and the chamfered corner portion. Inactive first
A film layer is formed, and an annular recess surrounding the root of the leg is formed on the bottle mouth contact surface of the brim, and a second inert layer is formed between the inner wall surface of the recess and the surface of the leg. A rubber stopper, wherein a film layer is formed, and a rubber surface is exposed at a bottle mouth contact surface located between an end portion of the first film layer and an end portion of the second film layer. 2. A rubber stopper comprising a brim portion that comes into contact with the upper end surface of the bottle mouth, and a leg portion that projects from the lower surface of the brim portion and is press-fitted into the bottle mouth, the side portion of the brim portion. The corner portion formed by the peripheral surface and the bottle mouth contact surface that contacts the upper end surface of the bottle mouth is chamfered, and the chemical solution is applied from the top surface portion of the brim portion to the side peripheral surface and the chamfered corner portion. Inactive first
A coat layer is formed, and a ring-shaped recess surrounding the root of the leg is formed on the bottle mouth contact surface of the brim. The second inner surface of the recess and the surface of the leg is inert to the chemical liquid. A rubber stopper, wherein a coat layer is formed, and a rubber surface is exposed at a bottle mouth contact surface located between an end portion of the first coat layer and an end portion of the second coat layer. 3. The rubber plug according to claim 1, wherein the recess has a seal ring. 4. A lower die having recesses for forming legs is laid with a first film inert to an encapsulating chemical solution, and an unvulcanized rubber sheet is laid on the first film. A second film which is inert to the enclosed chemical liquid is laid on a rubber sheet, and an upper mold having a recess for forming a brim is provided above the second film so as to face the recess for forming the leg. Then, the upper mold and the lower mold are heated and pressed to form a multi-formed sheet of the rubber plug element body, and the multi-formed sheet of the rubber plug element body is punched out to obtain a rubber plug. Therefore, a recess having a large outer diameter of the brim is formed in the lower mold, and the peripheral edge of the recess is chamfered to form a leg recess at the center of the recess. A rubber plug element body is used, in which a ring-shaped convex portion surrounding the concave portion for the leg is formed around the concave portion. After the punching process of the multi-forming sheet, a cylindrical member having the same size as the ring concave portion is inserted into the ring concave portion formed on the bottle mouth contact surface of the rubber stopper body by the ring convex portion, and The rubber plug element is held by a member and a member that supports the top surface of the brim portion, and the tubular shape is located at a position shallower than the bottom portion of the ring recess and from the middle of the chamfered corner portion of the side surface portion of the brim portion. A method for manufacturing a rubber stopper, characterized in that a rubber surface is exposed between the chamfered corner portion and the ring recessed portion by horizontally cutting the tip end of the member.