Patent Application
20190248060
The present disclosure relates to a synthetic resin preform having a cylindrical mouth portion provided with a male thread on an outer peripheral surface, a cylindrical body portion continuous with the mouth portion and a bottom portion closing the lower end of the body portion, the synthetic resin preform being formed into a container of a predetermined shape by blow molding; and a container containing contents formed by closing, with a cap, the mouth portion of the container in which the contents are stored.
Conventionally, as a container to contain beverage, detergent, and toiletry such as shampoo, hand soap or the like as contents, synthetic resin containers formed by synthetic resin materials such as polyethylene (PE), polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET) are frequently used.
Such container is generally formed into a predetermined shape by blow molding a synthetic resin preform integrally provided with a cylindrical mouth portion, a cylindrical body portion continuous with the mouth portion and a bottom portion closing a lower end of the body portion as illustrated in Patent Literature 1 (PTL 1), for example. Further, contents are filled in a container formed by blow molding and the mouth portion thereof is closed by a cap, and thus a container containing contents is provided.
PTL 1: JP2013-209101A
The conventional preform disclosed in PTL 1 includes a neck ring (support flange) between a mouth portion and a body portion, the neck ring protruding radially outward from the outer peripheral surface of the mouth portion, and when blow molding is performed, the undersurface of the neck ring is brought in abutment with the upper surface of the mold, and thus, for blow molding, the preform is held by the mold with an opening of the mouth portion facing upward. In this manner, for blow molding, the preform is held by a mold with an opening of the mouth portion facing upward, and the preform can be easily and reliably formed into a predetermined shape by blow molding.
However, for containers used for containing contents such as toiletry such as detergent, shampoo, hand soap or the like, a preform can not be provided with a neck ring for design problems. In this case, a preform cannot be held by a mold for blow molding with a mouth portion exposed out of the mold, thus blow molding cannot be adopted.
The present disclosure is to solve the above problem, and the present disclosure is to provide a synthetic resin preform capable of being molded into a container by blow molding using a mold without providing a neck ring, and a container containing contents provided with no neck ring.
The disclosed synthetic resin preform is a synthetic resin preform having a cylindrical mouth portion provided with a male thread on an outer peripheral surface, a cylindrical body portion continuous with the mouth portion and a bottom portion closing a lower end of the body portion, the synthetic resin preform being formed into a container of a predetermined shape by blow molding. The synthetic resin preform further includes a holding surface between the mouth portion and the body portion, the holding surface being continuous with an outer peripheral surface of the mouth portion and extending radially inward relative to the outer peripheral surface.
In the disclosed synthetic resin preform configured in the above described manner, preferably, the diameter of the outer peripheral surface of the mouth portion is the same as that of an outer peripheral surface of the body portion, a recessed groove dented radially inward relative to the outer peripheral surface of the mouth portion is provided between the mouth portion and the body portion, and a part of an inner surface of the recessed groove forms the holding surface.
In the disclosed synthetic resin preform configured in the above described manner, preferably, the recessed groove extends over the periphery between the mouth portion and the body portion.
In the disclosed synthetic resin preform configured in the above described manner, preferably, the diameter of the outer peripheral surface of the mouth portion is larger than that of the outer peripheral surface of the body portion, and the holding surface is continuous with the outer peripheral surface of the mouth portion at an outer peripheral edge and is continuous with the outer peripheral surface of the body portion at an inner peripheral edge.
In the disclosed synthetic resin preform configured in the above described manner, preferably, a cylindrical outer cover provided with a locking groove in an outer peripheral surface and provided also with a female thread provided on an inner peripheral surface is attached to the mouth portion with the female thread screwed with the male thread.
The disclosed container containing contents has: a synthetic resin container having a cylindrical mouth portion provided with a male thread on an outer peripheral surface, a container body portion continuous with the mouth portion and containing contents, and a holding surface provided between the mouth portion and the container body portion, continuous with an outer peripheral surface of the mouth portion and extending radially inward relative to the outer peripheral surface; a cylindrical outer cover including a locking groove in an outer peripheral surface and a female thread on an inner peripheral surface and fixed to the mouth portion with the female thread screwed with the male thread; and a cap provided with an engagement piece engaging with the locking groove in an undercut manner, the cap being attached to the outside of the outer cover to close the mouth portion.
According to the present disclosure, a synthetic resin preform that can be formed into a container by blow molding using a mold can be provided without the preform being provided with a neck ring, and a container containing contents provided with no neck ring can be also provided.
In the accompanying drawings:
The present disclosure will be illustrated in more detail below with reference to the drawings.
The synthetic resin preform 1 (hereinafter referred to merely as “preform 1”) of an embodiment of the present disclosure illustrated in
The preform 1 is not limited to those formed by injection molding a synthetic resin material, and it may be those formed by compression molding or extrusion blow molding a synthetic resin material.
The preform 1 has a cylindrical mouth portion 11, a cylindrical body portion 12 integrally continuous with the mouth portion 11, and a hemispherical bottom portion 13 integrally continuous with the lower end (the end on the lower side in
The outer peripheral surface 11a of the mouth portion 11 is integrally provided with a male thread 11b used to attach an outer cover 20 described later.
Further, a holding surface 14 continuous with the lower end of the outer peripheral surface 11a of the mouth portion 11 and extending radially inward relative to the outer peripheral surface 11a is provided between the mouth portion 11 and the body portion 12. The holding surface 14 is vertical to the axial direction of the mouth portion 11 and the body portion 12 and is directed to the bottom portion 13 (directed downward in
In this embodiment, a recessed groove 15 dented radially inward relative to the outer peripheral surface 11a of the mouth portion 11 and the outer peripheral surface 12a of the body portion 12 is provided between the mouth portion 11 and the body portion 12, and a part of the inner surface of the recessed groove 15 forms the holding surface 14. In greater detail, the recessed groove 15 is formed into an annular shape extending over the entire circumference of the mouth portion 11 or the body portion 12 between the mouth portion 11 and the body portion 12, and the cross-section vertical to the circumferential direction has a rectangular shape. Further, out of three inner surfaces of the recessed groove 15, the surface facing downward in
Although the boundary between the mouth portion 11 and the body portion 12 of the preform 1 is not clear, the shape of the mouth portion 11 does not change even after the preform 1 is blow molded, and thus the mouth portion 11, as it is, becomes the mouth portion of the container after molding. The body portion 12 is a portion to be axially and radially stretched by blow molding to form a container body portion of the container after molding.
In this embodiment, in order to allow the preform 1 to be transferred easily, an outer cover 20 is attached to the mouth portion 11 as illustrated in
Next, a process of forming the preform 1 configured in the above described manner into a container of a predetermined shape by blow molding (a blow molding method) is described.
First, as illustrated in
Next, as illustrated in
Preferably, before the preform 1 is attached to the mold 31, the body portion 12 and the bottom portion 13 are previously heated, by a heater or the like, up to a predetermined temperature at which a stretch effect is expressed. In this case, the preform 1 may be heated before the outer cover 20 is attached to the mouth portion 11 or after the outer cover 20 is attached to the mouth portion 11. Moreover, in consideration of productivity, the preform 1 may be attached to the mold 31 at a predetermined temperature by what is called a hot preform method in which the residual heat generated when the preform 1 is molded by injection molding or extrusion molding or the like is used.
An opening 31a used for disposing the preform 1 is provided on the upper surface of the mold 31, and the preform 1 is attached to the mold 31 with its mouth portion 11 protruding upward and outward from the opening 31a and with the body portion 12 and the bottom portion 13 disposed in the cavity 31b of the mold 31. The cavity 31b has a bottle shape corresponding to a container after molding. Further, although not illustrated in detail, the mold 31 can be opened right and left, and a container after molding can be ejected from the mold 31 by opening the mold 31.
In this case, the inner peripheral edge of the opening 31a of the mold 31 is provided with a protrusion 32. The protrusion 32 is formed into a rib shape with a thickness equal to or smaller than the groove width of the recessed groove 15, and is provided annularly over the entire circumference of the opening 31a. Further, the protrusion 32 is disposed in the recessed groove 15 of the preform 1, and the holding surface 14 is supported by the upper surface of the protrusion 32, which allows the preform 1 to be held by the mold 31.
Next, a nozzle (not illustrated) disposed on top of the mold 31 is lowered and is inserted into the mouth portion 11 of the preform 1. Further, the compressed air is supplied into the preform 1 through the nozzle to form the preform 1 into a container of a predetermined shape. In this manner, the preform 1 disposed in the mold 31 is blow molded, and as illustrated in
Further, the preform 1 is held in the mold 31 by the holding surface 14 that is supported by the top surface of the protrusion 32. Thus, even if the compressed air is supplied to the mouth portion 11 from above by blow molding, the preform 1 is prevented from being dropped off from the mold 31 due to the supply pressure during blow molding.
During blow molding, the body portion 12 of the preform 1 may be stretched in the longitudinal direction (axial direction) by the stretching rod that moves forward through the nozzle. With the stretching rod, the body portion 12 of the preform 1 can be radially stretched by the compressed air while being axially stretched by the stretching rod. In this case, preferably, the axial stretch of the body portion 12 by the stretching rod is performed before the compressed air is supplied into the body portion 12. However, it may be performed simultaneously with the supply of the compressed air into the body portion 12.
When the blow molding is finished, the nozzle is moved upward to be detached from the mouth portion 11, and subsequently the mold 31 is opened right and left. Further, the chuck 30a of the transfer machine 30 is engaged again with the locking groove 20a of the outer cover 20. Then the container 40 after molding is ejected from the mold 31 by the transfer machine 30 and the container 40 is transferred to the contents filling process. Further, as illustrated in
As described above, the container 40 is formed by blow molding the preform 1 and after the container 40 is filled with the contents 42, the cap 43 is mounted to the outer cover 20. As a result, a container containing contents 50 can be manufactured, the container containing contents 50 having the synthetic resin container 40 including the cylindrical mouth portion 11 provided with the male thread 11b on the outer peripheral surface 11a, the container body portion 41 continuous with the mouth portion 11 and containing the contents 42, and the holding surface 14 provided between the mouth portion 11 and the container body portion 41, continuous with the outer peripheral surface 11a of the mouth portion 11 and extending radially inward relative to the outer peripheral surface 11a; a cylindrical outer cover 20 including the locking groove 20a in the outer peripheral surface and the female thread 20b on the inner circumferential surface, and fixed to the mouth portion 11 with the female thread 20b screwed with the male thread 11b; and the cap 43 provided with the engagement piece 43a engaging with the locking groove 20a in an undercut manner, the cap being attached to the outside of the outer cover 20 to close the mouth portion 11.
As described above, the disclosed preform 1 is provided with, between the mouth portion 11 and the body portion 12, the holding surface 14 extending radially inward from the outer peripheral surface 11a of the mouth portion 11, and the protrusion 32 of the mold 31 is engaged with the holding surface 14 to hold the preform 1 in the mold 31 such that the preform 1 is prevented from dropping off. Thus, the preform 1 can be easily and reliably formed into the container 40 by blow molding without being provided with a neck ring, Further, instead of the neck ring, the preform 1 is configured to include the recessed groove 15, and as a result of this, the preform 1 and the container 40 are made lighter in weight and the portion below the recessed groove 15 can be easily stretched during blow molding. Moreover, by using the container 40 formed by blow molding the preform 1, a container containing contents 50 including no neck ring can be provided.
In the preform 1 illustrated in
On the other hand, in the variation of the preform 1 illustrated in
According to the above described configuration, without providing the opening 31a of the mold 31 with the protrusion 32 of a shape corresponding to the recessed groove 15, the holding surface 14 is supported by the opening edge of the opening 31a to hold the preform 1 in the mold 31. Thus it is not necessary to consider the strength or the like of the protrusion 32, and the degree of freedom in the design of the mold 31 can be enhanced.
The present disclosure is not limited to the above described embodiment, and may be changed in various manners without departing from the gist thereof.
For example, in the above described embodiment, the preform 1 is made of synthetic resin such as polyethylene (PE), polypropylene (PP), polystyrene (PS) or the like. But it is not limited thereto, and the preform 1 may be made of other synthetic resin materials.
Further, in the above described embodiment, although the case where the preform 1 is formed, by blow molding, into a container 40 that contains toiletry such as shampoo, hand soap or the like as contents is illustrated, it is not limited thereto, and the preform 1 may be formed into a container that contains other contents.
Moreover, in the above described embodiment, although the holding surface 14 or the recessed groove 15 is formed into an annular shape extending over the entire circumference of the mouth portion 11 or the body portion 12, it is not limited thereto, and it may be formed into a shape extending over only a portion of the circumference of the mouth portion 11 or the body portion 12. In this case, the protrusion 32 of the mold 31 and the opening edge of the opening 31a are also formed into a shape corresponding to the holding surface 14 or the recessed groove 15.
Furthermore, in the above described embodiment, although the preform 1 is blow molded by the compressed air as a pressurizing medium, it is not limited thereto, and the preform 1 may be molded by liquid blow molding in which liquid is used as a pressurizing medium. In this case, preferably, as a liquid supplied to the preform 1 during the liquid blow molding, contents filled finally into the container 40 as a product is used. As a result of this, the process of filling the contents in the container 40 after molding is omitted, and thus the productivity can be improved.
Moreover, in the above described embodiment, although the container 40 is transferred to the contents filling process with the outer cover 20 attached to the mouth portion 11, and after the container 40 is filled with contents, the cap 43 is attached to the outside of the outer cover 20 attached to the mouth portion 11 to close the mouth portion 11, it is possible that, after the container 40 is transferred to the contents filling process with the outer cover 20 attached to the mouth portion 11 and the container 40 is filled with the contents, the outer cover 20 is detached from the mouth portion 11 and a screw cap is directly attached to the mouth portion 11 to close the mouth portion 11. Alternatively, without the outer cover 20 being attached to the mouth portion 11, the preform 1 may be transferred with the mouth portion 11 being directly held by the chuck 30a of the transfer machine 30.
Furthermore, in the above described embodiment, although the preform 1 is illustrated as a single layer structure formed only of one kind of synthetic resin material, it is not limited thereto, and the preform 1 may have a lamination structure formed by laminating some kinds of synthetic resin materials. In this case, although the preform 1 may be formed by adhering multiple resin layers to each other, other than that the preform 1 may be formed into a laminated structure in which an outer layer and an inner layer are made respectively of materials different from each other so that they don't adhere to each other or may be formed into a laminated structure in which an axial zonal adhesive layer is provided between an outer layer and an inner layer. In this manner, when the preform 1 is formed into a laminated structure in which an outer layer and an inner layer are not adhered to each other, the preform 1 can be formed into a delaminated container by blow molding. The preform 1 of laminated structure is not limited to the above described structures, and a variety of layer structures can be adopted.
1 Synthetic resin preform
11 Mouth portion
11
a Outer peripheral surface
11
b Male thread
12 Body portion
12
a Outer peripheral surface
13 Bottom portion
14 Holding surface
15 Recessed groove
20 Outer cover
20
a Locking groove
20
b Female thread
20
c Flange
30 Transfer machine
30
a Chuck
31 Mold
31
a Opening
31
b Cavity
32 Protrusion
40 Container
41 Container body portion
42 Contents
43 Cap
43
a Engagement piece
50 Container containing contents
| Number | Date | Country | Kind |
|---|---|---|---|
| 2016-150456 | Jul 2016 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2017/020109 | 5/30/2017 | WO | 00 |
