JP2000037788A - Method for producing resin-made ampule - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method for producing resin-made ampule by injecting content into a body part through the opening part formed at the leading end of a neck part and subsequently closing the opening part of the leading end of the neck part surely in high yield to mold the leading end of the neck part into a semispherical shape almost perfectly. SOLUTION: A flange-shaped thick-walled part 3b is formed to the periphery of the opening part 3a provided to the leading end of a neck part 3 and, when the opening part 3a is closed, a first mold 51 having a through-hole 51d communicating with the outside formed to the deepest part thereof is pressed to the leading end of the neck part 3. By this constitution, the opening part 3a is closed while the air in an ampule is allowed to escape to the outside through the through-hole 51d and, after a projected resin sump 3c is formed to the leading end of the neck part 3, a second mold 52 having an almost semispherical recessed part is pressed to the leading end of the neck part 3 and the resin sump 3c is leveled to mold the leading end surface of the neck part 3 into an almost semispherical shape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a resin ampoule.

[0002]

2. Description of the Related Art An ampoule for accommodating a drug solution or the like is generally made of glass, and its contents are extracted by breaking off a neck integrally formed above a body. When manufacturing such an ampoule, an opening is formed at the tip of the neck, the contents are injected into the body through the opening, and then the glass is melted by heating the tip of the neck. Close the opening.

In recent years, attempts have been made to produce ampules made of a resin such as polypropylene instead of glass. Conventionally, in the production of such a resin ampoule, a direct blow molding method has been mainly employed, but the injection of the contents is the same as that of a glass one, and an opening provided at the tip of the neck is provided. After the contents are injected from the opening, the resin in the vicinity of the opening is heated and molded to close the opening.

[0004]

By the way, in the case of an ampoule made of a resin such as polypropylene, the step of closing the opening at the tip of the neck portion is performed due to its material properties.
It is not possible to adopt a process of melting the material like a glass ampoule and deforming it into a spherical shape in almost free state due to its surface tension and gravity and closing the opening, so that the neck of the neck is heated while heating. A molding method is generally adopted in which a mold having a hemispherical inner surface is pressed to cause the resin near the tip end of the neck to follow the inner surface of the mold. However, the resin is softened by heating or molded by a mold in a molten state, and the mold is pressed only from the outside while the ampule is set upright because the contents are already contained in the ampule. Things,
Due to the expansion of the gas inside the ampoule due to heating during molding, or due to the resin in the neck flowing inward by pressing the mold against the tip of the neck, the gas in the ampoule escapes outside, Under the influence of the internal pressure being generated at the moment the resin at the tip of the neck closes the opening in the heated and molten state, the opening is securely closed, and the tip of the neck is formed into a substantially spherical shape. It was extremely difficult to obtain a good design.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ampoule made of a resin such as polypropylene, which ensures that the opening at the tip of the neck is closed with a high yield after injecting the contents, and that the tip of the neck is almost completely hemispherical. It is an object of the present invention to provide a method for producing a resin ampoule that can be molded into a resin.

[0006]

In order to achieve the above object, a method for producing a resin ampoule according to the present invention comprises a body portion for containing contents, and a body portion located above the body portion and having an interior. Communicates with the inside of the body, and integrally forms a neck having an opening at the tip with resin, and after injecting the contents into the body through the opening, the resin closing the opening. The method for producing an ampoule is characterized in that a flange-shaped thick portion is formed on the outer periphery of an opening at the tip of the neck, and the step of closing the opening includes the following first and second steps. (Claim 1).

A first step; having a concave surface having an opening diameter into which the tip of the neck fits and having an inner diameter smaller toward the inner side, and a through hole communicating with the outside at the innermost part; A forming step of using the first mold to heat and soften the tip portion of the neck while making the end face and the side face in the vicinity thereof conform to the concave face of the first mold.

A second step: an ampoule that has undergone the first step using a second mold having an opening diameter into which the tip of the neck fits and having a concave surface with a substantially hemispherical end surface. Forming the end face and the side face in the vicinity thereof along the concave face of the second mold while heating and softening the tip of the neck.

In the present invention, the concave surface of the first mold, the inner peripheral surface of the through hole, and the concave surface of the second mold are each coated with a fluorine-based highly lubricious resin. (Claim 2) is desirable.

The present invention was made as a result of studying various problems in the conventional closed molding method in which a mold having a hemispherical inner surface is simply pressed against the tip of the neck, and a study of the behavior of the resin at that time. is there. That is, if the mold at the tip of the neck is heated and softened or melted and the mold is pressed only from the outside of the ampoule, the resin flows along the inside of the mold so as to close the opening, The internal pressure due to the expansion of the gas inside, or the gas that escapes from the inside of the ampoule by pressing the mold against the tip of the neck, pushes the resin in the flowing state to the surroundings along the hemispherical surface of the mold. For this reason, the resin in the central portion of the front end of the neck portion is insufficient, and the opening is not sufficiently closed, or the resin in the same portion becomes thinner and a depression occurs.

In the present invention, the step of closing the opening at the tip of the neck is divided into two steps. In the first step, the center of the tip of the neck is formed at the innermost portion of the first mold in contact. By letting the gas in the ampoule escape to the outside through the through hole and at the same time letting a predetermined amount of resin enter into this through hole, a convex portion is formed at the tip of the neck of the ampule after the first step.
That is, a resin pool is formed. The amount of resin necessary for forming the resin pool is covered by a thick portion formed in a flange shape around the opening of the neck portion before the closing molding. Then, in the subsequent second step, the second mold having a substantially hemispherical concave surface corresponding to the final product shape is pressed against the tip of the neck portion to adjust the resin pool, so that the neck portion is not run short. The opening at the tip can be reliably closed, and the outer surface can be formed into a hemispherical surface.

Further, as in the second aspect of the present invention, the first
By coating the concave surface of the mold, the inner peripheral surface of the through hole, and the concave surface of the second mold with a fluorine-based highly lubricating resin, the releasability of the resin in the first and second steps is improved. It is possible to further improve the above-described operation and effect.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. First, the final structure of a resin ampoule to be obtained by the method of the present invention will be described. As shown in the front view of FIG. 1, a body 1 for accommodating contents has a tip (upper) portion. Are connected to a shoulder 2 having a gradually decreasing diameter, and a neck 3 is provided above the shoulder 2. A boundary portion between the shoulder portion 2 and the neck portion 3 is thicker than the other portion, and a cutout portion 4 for breaking off the neck portion 3 is formed in the circumference thereof. In addition, the tip of the neck 3 is formed in a substantially hemispherical shape by closing the opening in a closing forming step described later after injecting the contents.

FIGS. 2 and 3 are explanatory views of an example of a process for producing an ampoule before injecting the contents. FIG. 4 is an enlarged view of the vicinity of the tip of the neck 3 in each of these figures. In this example, the case where the ampoule before the content injection is formed by the injection blow molding method is shown. That is, first, a semi-finished product as shown in FIG. 2 is molded by an injection molding method. In FIG. 2, a portion below a line indicated by PL indicates a region to be formed by a blow molding process in a later step, and a portion above the opening is an opening formed at a tip of a neck portion 3 to be described later for injecting contents. Except for the molding for closing the block 3a, the region to be molded into the final product shape by the injection molding method is shown. Therefore, the upper part of the neck part 3, the cut part 4, and the shoulder part 2 in the final product is molded by the injection molding method. During this injection molding, a flange-shaped thick portion 3b is formed around an opening 3a formed at the tip of the neck portion 3. This flange-shaped thick portion 3b is formed as shown in FIG.
As shown in FIG. 5, in this example, the width B is 1.5 mm, and the thickness t is 1.75 mm. Incidentally, the inner diameter d of the opening portion 3a is 7.5 mm, the thickness t ₀ of the neck portion 3 immediately below the thick portion 3b is a 1.25 mm, the thickness t ₀
And the lower end of the thick portion 3b are connected by a slope of about 45 °.

The semi-finished product shown in FIG. 2 has a blow molding resin portion 1 below the PL in a subsequent blow molding process.
0 is formed into the shape of the trunk 1 as shown in FIG. In this blow molding step, the semi-finished product of FIG. 2 is inserted into the blow cavity, and the stretch rod of the blow core is blown through the opening 3a of the neck 3 to form the blow molding resin portion 10.
This is done by inserting it into

The molded product shown in FIG. 3 which has been formed into the final product shape except that the opening 3a is formed at the tip of the neck 3 is then inserted into the body 1 through the opening 3a. After the contents are injected, the opening 3a is closed by a closing molding process described in detail below.

FIGS. 5A and 5B are central longitudinal sectional views showing the structures of a first mold 51 and a second mold 52 used in a step of closing the opening 3a. The first mold 51 is used for the neck 3 of the molded product shown in FIG. 3 or FIG.
Has an open end 51a having a diameter such that the tip of the
The open end 51a has a tapered surface 51b and a partial spherical surface 5b.
1c, which has a concave surface whose inner diameter gradually decreases as it goes to the far side. A through hole 51d communicating with the outside is formed in the innermost part. In the through-hole 51d, a draft is formed in a predetermined region on the concave surface side of the mold 51 such that the diameter increases toward the concave surface side.

On the other hand, the second mold 52 is
The opening end 52a has a diameter equal to that of the opening end 51a, and the opening end 52a is connected to a concave surface composed of a tapered surface 52b having a smaller diameter toward the back and a closed hemispherical surface 52c connected to the tapered surface 52b.

Further, the entire surface of the tapered surface 51b and the partial spherical surface 51c of the first mold 51, the region where at least the draft is formed in the through hole 51d, and the tapered surface 5 of the second mold 52
The 2b and the hemispherical surface 52c are coated with a fluorine-based highly lubricious resin such as Teflock (trade name).

In the molded article of FIG. 3 into which the contents are injected through the opening 3a, after the tip region of the neck 3 near the opening 3a is heated, first, in the first step, the first metal is used. The mold 51 is pressed along the axis of the neck 3 in a direction in which the concave mold surface faces the opening 3a. As a result, FIG.
As shown in (A), the tip of the neck 3 has a tapered surface 51.
b and the partial spherical surface 51c, the opening 3a is gradually closed. During this time, the gas that has been heated and expanded in the ampoule, or the gas that has been displaced by the resin at the tip of the neck portion 3 flowing inside, escapes to the outside through the through-hole 51d. Then, as shown in FIG. 3B, the opening 3a is completely closed, and the resin mainly composed of the resin forming the thick portion 3b on the outer periphery of the opening 3a enters the through hole 51d. State. Therefore, as shown in the cross-sectional view of FIG. 6B, the ampoule that has undergone the first step is formed such that the tip of the neck 3 is formed into a substantially hemispherical surface, the opening 3a is closed, and the center of the tip surface is Is formed in a state where a convex resin reservoir 3c is formed.

The ampoule that has passed through the first step is then
In the step (2), the second mold 52 is similarly pressed against the tip of the neck 3. As a result, as shown in FIG. 6C, the resin pool 3c at the tip of the neck 3 is adapted,
The surface is a hemispherical surface 52 at the end of the concave surface of the second mold 2.
It is formed to have a hemispherical surface along c. This second
In the step (3), the presence of the resin pool 3c formed on the distal end surface of the neck 3 prevents the formation of a hollow or a hole due to the occurrence of a thin portion due to lack of resin in the central portion of the distal end surface of the neck 3, and the neck 3 At the same time, the tip of the ampule is formed into a substantially perfect hemispherical surface, and an ampoule having the shape shown in FIG. 1 is obtained.

In the first and second steps, the releasability of the resin is improved due to the presence of the fluorine-based resin coated on the resin contact surfaces of the first and second molds 51 and 52. In addition, it is possible to eliminate the occurrence of molding failure due to the adhesion of the molten resin to the mold at the time of mold release.

In the above embodiment, an example is shown in which the injection blow molding method is employed for forming an ampule except for the step of closing the opening 3a, but the present invention is not limited to this. Of course, other molding methods, such as a direct blow molding method, may be adopted.

[0024]

As described above, according to the present invention, a flange-shaped thick portion is formed around the opening formed at the tip of the neck of the ampule, and the step of closing the opening is performed by the following steps. By pressing a first mold having a through-hole formed in the innermost part against the tip of the neck, the gas in the ampoule escapes to the outside through the through-hole and closes the opening, and at the same time, the resin accumulates at the tip. And a second mold having a concave surface consisting of a substantially hemispherical surface pressed against the tip of the neck of the ampoule that has undergone the first step, thereby acclimating the resin pool. Since the process is performed in the second step of forming the surface into a substantially hemispherical shape, a thin portion due to insufficient resin is generated in the closed portion of the opening, and a depression is generated at the tip of the neck, or a hole is opened in the closed portion and the closed portion is closed. Is incomplete Flip not always with the opening can be completely closed, it is possible to obtain an excellent design property as the shape always as designed even the tip face shape.

[Brief description of the drawings]

FIG. 1 is a front view showing an overall configuration of a resin ampule obtained according to an embodiment of the present invention.

FIG. 2 is a front view showing a configuration of a molded product obtained by injection molding in the embodiment of the present invention.

FIG. 3 is a front view showing a configuration of a molded product obtained by blow molding the molded product of FIG. 2;

FIG. 4 is an enlarged view of the vicinity of the distal end of a neck 3 of the molded product of FIGS. 2 and 3;

FIG. 5 is a central longitudinal sectional view of a first mold (A) and a second mold (B) used in a step of forming an opening in an opening portion of the present invention.

FIG. 6A is an explanatory view of a step of closing the opening 3a in the embodiment of the present invention, FIG. 6B is a first step, and FIG. It is explanatory drawing of a 2nd process.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Body part 2 Shoulder part 3 Neck part 3a Opening part 3b Thick part 3c Resin pool 4 Notch part 10 Blow molding resin part 51 First mold 51a Open end 51b Tapered surface 51c Partial spherical surface 51d Through hole 52 Second gold Mold 52a Open end 52b Tapered surface 52c Hemispherical surface

Claims (2)

[Claims] 1. A body for accommodating contents, and a body located above the body and communicating with the inside of the body, and
A method of manufacturing a resin ampoule that integrally forms a neck portion having an opening at a distal end portion thereof with a resin, injects contents into the body portion through the opening portion, and then closes the opening portion. A flange-shaped thick portion is formed on the outer periphery of the opening at the tip, and the step of closing the opening has an opening diameter into which the tip of the neck fits, and the inner diameter decreases toward the back. Using a first mold having a concave surface and having a through-hole communicating with the outside at the innermost portion, the end surface and the side surface near the end surface are heated and softened while heating the tip portion of the neck. First along the concave surface of the mold 1
Using a second mold having an opening diameter into which the tip of the neck fits and a concave surface having a substantially hemispherical end surface formed thereon, using the second mold having undergone the first molding step. A second step of heating and softening the tip of the neck while making the end face and the side face in the vicinity thereof along the concave face of the second mold. 2. The method according to claim 1, wherein the concave surface of the first mold, the inner peripheral surface of the through hole, and the concave surface of the second mold are each coated with a fluorine-based highly lubricating resin. 2. The method for producing a resinous ampule according to item 1.