JPH10151664A - Bottle pack container molding method and molding mandrel - Google Patents

Abstract

[PROBLEMS] To form a thin opening portion 12 on the tip end surface of a neck portion 11, the opening edge 11 a bulges up, and the shape of the opening edge 11 a in the opened state tends to be uniform. And a molding mandrel. SOLUTION: A container 1 is provided on a distal end surface of a sleeve-shaped main body 20.
The ring-shaped projection 21 for forming the opening portion, which is close to the tip end surface of the neck forming portion 31 in the split body-forming molds 3, 3 at the time of molding, and is inserted into the neck forming portion 31 via a predetermined gap. When the opening portion 12 of the container 1 is formed by using the mandrel 2 having the sleeve-shaped core portion 22 protruded concentrically, the heat of the parison a forming the neck portion 11 is formed by the core portion 22. Plastic synthetic resin,
It is characterized in that it is pressed from the neck forming part 31 toward the tip of the neck forming part 31.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a bottle pack container and a mandrel for molding a bottle pack container suitable for carrying out the method.
Here, the bottle pack container is a plastic bottle-shaped container in which blow molding, filling, and sealing are performed in a series of steps ("PHARM TECH JAPAN" V
OL. 5 No7, 1989, 89th (793)
Page), for example, is widely used as a so-called unit-dose type ophthalmic solution filling container filled with an amount of liquid agent used once or several times.

[0002]

2. Description of the Related Art FIGS. 9 and 10 show a unit dose type bottle pack container filled with this kind of eye drops. FIG. 9 is a perspective view of the bottle pack container, and FIG.
0 is a partially enlarged sectional view of the container. The bottle pack container 1 includes a bottle-shaped main body 10 having an upper end integrally formed with a neck portion 11 via a shoulder portion 13, and a cap portion 15 for sealing the bottle-shaped main body 10. A holding piece 14 is formed integrally with the lower end of the cover member, and a knob 16 is formed integrally with the cap portion 15. As shown in FIG. 10, a thin opening portion 12 is formed on the distal end surface (boundary between the neck portion 11 and the cap portion 15) of the neck portion 11, and the bottle-shaped main body 10 is formed.
It is filled with an amount of the liquid agent b that can be used once or several times. When the liquid agent b is used, the bottle-shaped main body 10 or the holding piece 14 is held in one hand, the knob 16 is gripped with the other hand, and the cap 15 is twisted or pressed toward the main body 1 to obtain the liquid The opening portion 12 is broken to open the tip of the neck portion 11.

[0003] A conventional molding method of this kind of bottle pack container will be described with reference to Figs. Each of the molding dies is formed into two halves, and the body molding dies 3 and 3 installed in order from the bottom, the cap molding dies 4 and 4 also serving as the sealing dies, and the holding dies 5 and And 5. A body molding cavity 30 for molding the bottle-shaped main body 10 and a cavity 32 for molding the holding piece 14 are formed on the opposing surfaces of the body molding dies 3 and 3 in contrast to each other. The upper end portion forms a neck forming portion 31 for forming the neck portion 11. A cavity 4 for forming a cap portion 15 and a knob portion 16 is provided on the opposing surfaces of the cap portion forming dies 4, 4.
0 and 41 are formed in contrast. Each of the molds 3, 4, and 5 in this example is designed in a state where a plurality of sets are connected in the depth direction of FIG.

[0004] As shown in FIG. 4, the molds 3, 4, 5 are set in a state in which they are opposed to each other in a molding posture and are separated from each other to the right and left, and are moved below the parison head 6. A cylindrical parison a made of a molten thermoplastic synthetic resin is extruded at a constant speed between the left and right molds 3, 4, and 5. When the parison a is extruded to an appropriate length, only the body molding dies 3 and 3 are united, and the parison a is cut by a parison cutter (not shown) under the parison head 6 while the extrusion of the parison a is continued. . At this time, the lower end of the parison a is sealed by the body mold 3, and the upper end of the parison a is held by the uppermost holding molds 5, 5, and in this state, each mold is moved to another position. Next, as shown in FIGS. 5 and 7, the mandrel 2 having the ring-shaped protrusion 21 formed on the distal end surface of the sleeve-shaped main body 20 is inserted into the upper end of the parison a, and the ring-shaped protrusion 21 is inserted into the body mold 3. , 3 to form a thin-walled unsealing portion 12 as shown in FIG. At the same time, each body mold 3,3
The gas in the cavities 30, 30 is suctioned from a number of fine suction holes (not shown) formed so as to pass from the body molding cavities 30, 30 to the outside of the dies 3, 3, thereby forming the bottle-shaped main body 10. At the same time, the liquid agent b is filled into the bottle-shaped main body 10 from the filling nozzle 7 inserted in the mandrel 2. After the liquid agent b is filled, while the parison a keeps its softness, the mandrel 2 is raised together with the filling nozzle 7, and the cap part forming dies 4, 4 as shown in FIG.
Are combined to form the cap portion 15 including the knob portion 16, and the molds 3, 3, 4, 4, 5, and 5 are separated from each other left and right. Then, the set of the dies 3, 4, and 5 is returned to the state of FIG.

In the above-described example, as described above, each of the molds 3,
Since a plurality of sets 4 and 5 are connected in the depth direction in FIG. 5, the bottle pack container 1 is formed in a state where a plurality of bottle pack containers 1 are connected side by side by one parison a. Then, the resin portion above the knob portion 16 of each of the connected bottle pack containers 1 and the resin film forming the interconnecting portion between the shoulder portion 13 and the knob portion 16 are removed by punching. In the above-described example, the parison a is deformed from the parison head 6 to such an extent that the opposing inner wall surfaces are not fused to each other.
The cleanly processed air is supplied into the parison a. In the above-described example, the bottle-shaped main body 10 is formed so as to expand by bleeding air so that the cavities 30, 30 of the dies 3, 3 are evacuated. When the capacity of the bottle-shaped main body 10 is relatively large, air is evacuated so that the cavities 30 and 30 are in a vacuum state as described above, and clean compressed air is blown from the mandrel 2. Is molded. In each case, it is commonly called blow molding. In addition to the liquid described above, the bottle pack container 1 may be filled with a powder or granule, cream or ointment. These are exactly the same for the present invention.

[0006]

According to the above-mentioned conventional molding method, as shown in FIG. 7, the ring-shaped projection 21 on the tip surface of the mandrel 2 is connected to the neck molding portion 3 of the body molds 3, 3.
When the thin opening portion 12 is formed by bringing the opening portion 11 close to the front end surfaces of the opening portions 11, 31, the opening edge 11 a of the neck portion 11 rises due to the ring-shaped projection 21. By pulling out, almost only the inner peripheral surface of the neck forming portion 31 is attracted (when clean air is blown into the parison a, it is pressed against the inner peripheral surface of the neck forming portion 31). The swelling of the inner peripheral portion 11a of the portion 21 tends to be non-uniform. For this reason, in a state where the opening portion 12 is broken open, the shape of the opening edge 11a of the neck portion 11 is, for example, as shown in FIG.
The shape of the opening edge 11a becomes unstable, for example, the shape becomes elliptical as shown in FIG. 7A, or the portion rises larger than the other portions as shown in FIGS. Not a few. Such deformation of the opening edge 11a becomes an obstacle when pouring a liquid agent or the like in the bottle-shaped main body 10, and also causes unevenness in the thickness of the opening portion 12 and the cap portion 15 due to a uniform force. Opening may be difficult.

An object of the present invention is to provide a bottle pack container in which when the thin opening portion 12 is formed on the distal end surface of the neck portion 11, the opening edge 11 a rises and the shape of the opening edge 11 a in the opened state tends to be uniform. To provide a molding method. Another object of the present invention is to provide a molding mandrel suitable for carrying out a molding method capable of achieving the above object.

[0008]

In order to solve the above-mentioned problems, a method for molding a bottle pack container according to the present invention is characterized in that a parison a made of an extruded thermoplastic synthetic resin is used to divide a body molding die 3, 3 into two parts. By bottle-shaped body 10
And the ring-shaped protrusion 21 of the mandrel 2 having the ring-shaped protrusion 21 formed on the front end surface of the sleeve-shaped main body 20 is brought close to the front end surface of the neck forming portion 31 of the body dies 3. When forming a thin-walled opening 12 at the tip end surface of the neck 11 of the bottle-shaped main body 10,
The thermoplastic resin of the parison a forming the neck portion 11 is transferred from the neck forming portion 31 to the neck forming portion 3.
1 is pressed in the direction of the tip.

According to a second aspect of the present invention, there is provided a mandrel for molding a bottle pack container. A ring-shaped protrusion 21 for forming an opening portion, which is close to the tip end surface of the neck forming portion 31 of the split body forming dies 3, 3, and inserted into the neck forming portion 31 via a predetermined gap. It is characterized in that the sleeve-shaped core portion 22 is protruded concentrically.

According to a third aspect of the present invention, in the molding mandrel of the second aspect, the outer peripheral surface of the core portion is formed as a conical surface slightly inclined when viewed from the side of the sleeve-shaped main body. It was done.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a molding mandrel and a bottle pack molding method according to the present invention will be described in detail. In the following description, description of the same components as those in the conventional example will be omitted. FIG. 1 is a partially enlarged cross-sectional view showing a state in which a bottle pack container is being formed using the mandrel of the embodiment of the present invention,
FIG. 2 is a partially enlarged cross-sectional view of the mandrel, and FIG. 3 is an end view of a neck portion of the bottle pack container formed by the forming method according to the embodiment of the present invention in an opened state.

The mandrel 2 of this embodiment is made of metal or ceramic, preferably stainless steel, and has a sleeve-shaped body 20 and an opening portion formed concentrically protruding from the distal end surface of the sleeve-shaped body 20. Ring-shaped projection 21
And a sleeve-shaped core portion 22. The ring-shaped projection 21 is integrally protruded from the outer peripheral edge of the distal end surface of the sleeve-shaped main body 20 at an acute cross section, and the sleeve-shaped core portion 22 is integrally protruded from the inner peripheral edge of the sleeve-shaped main body 20. . In this embodiment, the outer peripheral surface of the sleeve-shaped core portion 22 is formed as a slightly inclined conical surface when viewed from the side of the sleeve-shaped main body 20. When the bottle-shaped main body 10 of the bottle pack container 1 is formed, the ring-shaped protrusion 21 is brought close to the tip end surface of the neck forming portion 31 of the split body forming molds 3 and 3 which are united with each other. The core portion 22 is configured to be inserted into the neck forming portion 31 of the dies 3 and 3 via a predetermined gap.

[0013] The molding method of this embodiment uses the mandrel 2.
The other configuration is almost the same as the conventional molding method except that a sleeve-shaped core portion 22 is formed on the tip end surface of the conventional molding method. When the bottle pack container 1 is molded using the mandrel 2 of the embodiment, the bottle-shaped main body 1 in the molding process is formed.
The thermoplastic synthetic resin of the neck portion 0 is pushed in the direction of arrow c in FIG. 2 by suction of air from inside the body molds 3 and 3 or blowing of air into the parison a. As shown at d, the sleeve-shaped core 22 presses (pushes up) the neck forming portion 31 from the neck forming portion 31 toward the distal end thereof. As described above, the thermoplastic synthetic resin forming the neck portion 11 is formed by the neck molding portion 31.
When pushed toward the tip of the ring-shaped projection 21, it rises into a gap 23 formed inside the ring-shaped projection 21, and this gap 23 is filled with the thermoplastic synthetic resin. Rim 11a
Is formed so as to conform to the internal shape of the ring-shaped projection 21. Accordingly, the shape of the opening edge 11a is stable, and the opening edge 11a when the bottle pack container 1 is opened is opened.
Is substantially circular as shown in FIG.

According to the molding method of this embodiment, during molding of the bottle-shaped main body 10, the resin of the neck portion 11 of the bottle-shaped main body 10 is pressed from the neck-formed portion 31 of the dies 3, 3 toward the tip end thereof. Therefore, the bulge of the meat (resin) at the opening edge 11a becomes uniform, and the molding shape of the portion becomes stable (uniform). Therefore, the bottle-shaped body 1
In addition to smoothing the filling of the filler in the opening portion 0, the cap portion 15 can be opened with a uniform force because the thickness of the opening portion 12 becomes more uniform.

According to the molding mandrel of this embodiment, when molding the bottle-shaped main body 10 of the bottle pack container 1, the sleeve-shaped core portion 22 inserted into the neck molding portion 31 with a predetermined gap therebetween is used. Since the resin is made to protrude to the distal end surface of the sleeve-shaped main body 20, the resin of the neck portion 11 of the bottle-shaped main body 10 is reliably pressed from the neck portion 11 toward the distal end during the molding. In addition, since the outer peripheral surface of the core portion 22 is formed in a slightly conical surface so as to gradually decrease in diameter toward the distal end, the pressing of the resin as described above is performed extremely smoothly.

[0016]

According to the method for forming a bottle pack container according to the first aspect, when the bottle-shaped main body is formed, the resin of the neck portion of the bottle-shaped main body is replaced with the resin of the neck portion.
, The resin rises uniformly at the opening edge 11a, and the molding shape of the portion is stabilized. Therefore, the filling in the bottle-shaped main body 10 is smoothly performed, and the thickness of the opening portion 12 is uniform, so that the cap portion 15 can be opened with a uniform force.

According to the molding mandrel according to the second aspect, when molding the bottle-shaped main body 10 of the bottle pack container 1, the sleeve-shaped core portion 22 inserted into the neck molding portion 31 with a predetermined gap therebetween. Is projected to the distal end surface of the sleeve-shaped main body 20, so that the resin of the neck portion 11 of the bottle-shaped main body 10 is reliably pressed from the neck portion 11 toward the distal end during the molding. According to the molding mandrel according to claim 3, since the outer peripheral surface of the core portion 22 is formed as a conical surface that is slightly inclined when viewed from the side of the sleeve-shaped main body 20, such a resin as described above is used. The pressing is performed very smoothly.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view showing a state in which a bottle pack container is being formed using a mandrel according to an embodiment of the present invention.

FIG. 2 is a partially enlarged sectional view of the mandrel of FIG. 1;

FIG. 3 is an end view of the neck portion in a state where the bottle pack container molded by the molding method according to the embodiment of the present invention is opened.

FIG. 4 is a schematic sectional view of each mold for explaining one step of a conventional bottle pack molding method.

FIG. 5 is a schematic cross-sectional view of each mold and a mandrel for explaining a step subsequent to the step of FIG. 4;

FIG. 6 is a schematic cross-sectional view of each mold for explaining a step subsequent to the step of FIG. 5;

FIG. 7 is a partially enlarged cross-sectional view for explaining a forming process of an opening portion of the bottle pack container in the state of FIG. 5;

FIGS. 8A and 8B are end views of an opening portion of a bottle pack container molded by a conventional molding method, respectively, and FIG. 8C is an enlarged sectional view of the opening portion of FIG. It is.

FIG. 9 is a perspective view of a bottle pack container.

10 is a partially enlarged sectional view of the bottle pack container of FIG.

[Explanation of symbols]

 a parison b solution c, d arrow 1 bottle pack container 10 bottle-shaped main body 11 neck part 11a opening edge 12 thin opening part 13 shoulder part 14 holding piece 15 cap part 16 knob part 2 mandrel 20 sleeve-shaped body 21 ring-shaped projection 22 Sleeve-shaped core portion 23 Gap 3 Body molding die 30 Body molding cavity 31 Neck molding portion 32 Cavity 4 Cap molding die 40, 41 Cavity 5 Holding die 6 Parison head 7 Filling nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Sekine 3- 24-1, Takada, Toshima-ku, Tokyo Taisho Pharmaceutical Co., Ltd. (72) Inventor ▲ Junko Taka ▼ 3-24 Takada, Toshima-ku, Tokyo No. 1 Taisho Pharmaceutical Co., Ltd.

Claims (3)

[Claims] 1. A bottle-shaped main body 10 is formed from a parison a made of an extruded thermoplastic synthetic resin by means of a split body-forming mold 3, 3, and a ring-shaped projection 21 is formed on the tip end surface of a sleeve-shaped main body 20. The ring-shaped projection 21 of the mandrel 2 on which the
3, the thin opening portion 1 is attached to the distal end surface of the neck portion 11 of the bottle-shaped main body 10 in close proximity to the distal end surface of the neck forming portion 31.
2. The bottle pack container according to claim 1, wherein, when molding the bottle 2, the thermoplastic synthetic resin of the parison a forming the neck 11 is pressed from the neck molding 31 toward the tip of the neck molding 31. Molding method. 2. The front end surface of the sleeve-shaped main body 20 is brought close to the front end surface of the neck forming portion 31 of the split body forming molds 3, 3 when the bottle-shaped main body 10 of the bottle pack container 1 is formed. A ring-shaped projection 21 for forming an opening portion;
A mandrel for molding a bottle pack container, wherein a sleeve-shaped core portion 22 inserted into the neck molding portion 31 through a predetermined gap is protruded concentrically. 3. The bottle pack container according to claim 2, wherein the outer peripheral surface of the core portion 22 is formed as a slightly inclined conical surface when viewed from the side of the sleeve-shaped main body 20. Mandrel for molding.