JP2018176550A - Method for producing liner-provided cap and liner-provided cap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a liner-provided cap and a liner-provided cap which can suppress an increase in production cost even when a display with high visibility is applied.SOLUTION: A method of producing a liner-provided cap capable of hermetically closing a mouth part of a container and having a cap body having a top face part and a cylindrical part substantially vertically suspended from a peripheral edge of the top face part and having a liner provided on an inner face of the top face part, has a liner molding process molding the liner having an annular seal part which is brought into close contact with the mouth part of the container by molding to press a mold against a molten resin supplied into the cap body, a thin wall part surrounded by the seal part, and a display recessed part formed on a surface of the thin wall part.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a method of manufacturing a liner cap that seals containers for beverages and the like, and a liner cap.

  As a cap mounted on a container made of steel, aluminum alloy or the like, one having a metal cap body and a liner provided on an inner surface of a top surface portion of the cap body is known. The liner abuts on the top of the mouth of the container so that the inside can be sealed.

  Conventionally, as a cap (a cap with a liner) including such a liner, a molten resin ball is dropped to the inner surface of the top surface portion of the cap body, and a liner having a predetermined shape is formed by embossing using a molding die. In-shell mold type metal caps are known. Since the linered cap formed by such a configuration is continuously manufactured by a plurality of molding dies, for example, from the viewpoint of traceability, an imprint is applied to each molding die.

Specifically, a marking (groove) by laser processing is formed in each of the molding dies, and the shape of the marking is transferred to the liner by solidifying in a state in which the resin is in the groove. .
An imprint for identifying such a mold is formed on a small area of the liner surface, as it does not have to be shown with particular emphasis on the consumer.

  On the other hand, for example, as disclosed in Patent Document 1, it has been proposed that laser processing is performed on the liner surface to form a hit display or out display such as a prize on the liner. In this case, in the configuration of Patent Document 1, since it is necessary to carry out laser processing for each liner cap, in the same way as the above-described marking on the molding die, the molding die is marked by laser processing and the marking It is conceivable to simultaneously produce a plurality of linered caps by means of a molding die in which the.

JP, 2009-227301, A

  By the way, these displays need to be displayed in a size easily recognizable by the consumer. In addition to the display of prizes and the like, the same applies to the case where a house mark or the like of the company is formed on the liner, and when emphasizing and shown to the consumer, it is necessary to form the liner surface with a large area. In particular, when the marking is formed on the molding die by the laser processing as described above, the indication is formed by the resin entering the groove (marking) of the molding die, so that the indication is more than the liner surface. Since it is formed in a projecting state, that is, as a convex portion, the amount of resin for forming the liner is increased, which causes a problem of an increase in manufacturing cost.

  The present invention has been made in view of such circumstances, and provides a method of manufacturing a lined cap and a lined cap that can suppress an increase in manufacturing cost even when a display with high visibility is provided. The purpose is

  A method of manufacturing a cap with liner according to the present invention comprises a cap body including a top surface portion and a cylindrical portion substantially suspended from the periphery of the top surface portion, and a liner provided on the inner surface of the top surface portion. A method of manufacturing a linered cap capable of sealing the mouth portion of a ring, the annular seal portion being brought into close contact with the mouth portion of the container by molding in which the mold is pressed against the molten resin supplied in the cap body. And a liner forming step of forming a liner having a thin portion surrounded by the seal portion and a display concave portion formed on the surface of the thin portion.

The liner formed by the liner forming process has an annular seal portion, a thin wall portion surrounded by the seal portion, and a display recess formed on the surface of the thin wall portion, which are formed in the cap body. It is formed by pressing the mold against the molten resin. For this reason, on the surface of the mold for pressing the molten resin, the annular recess forming the seal portion and the thin portion in the surface portion of the liner and the convex portion inside thereof and the surface of the convex portion are displayed on the thin portion And a projection that forms the recess. When the molten resin is pressed by the surface of a mold having such an annular recess, a protrusion and a protrusion, a seal portion and a thin portion are formed on the surface of the liner, and a display recess is formed on the thin portion. It is formed. The display recess is formed to be thinner than the thin portion. In other words, the thickness dimension of the display recess in the thin portion is smaller than the thickness dimension of the thin portion. Therefore, the amount of resin constituting the liner can be reduced and the manufacturing cost of the liner cap can be reduced, as compared with the case where the display portion is configured by the convex portion.
Moreover, when forming the said display in convex shape by the recessed part of a metal mold rather than the recessed part for display, in order that resin may entrap in the recessed part of metal mold, the said molten resin flows into the outside (seal part side) smoothly. In addition, a part of the liner may be missing, which reduces the yield of the liner. On the other hand, since the mold used in the liner forming step of the present invention forms the display recess by the projection projecting from the convex portion, when the resin is pressed by the surface of the mold, the resin is cut by the projection. It can flow smoothly to the outside. Thus, the yield of the liner can be increased.

In the method of manufacturing a liner cap of the present invention, the area of the display recess may be 3% or more and 50% or less of the area of the thin-walled portion in plan view on the inner surface of the cap body.
Here, when the area of the display recess is less than 3% of the area of the thin portion in plan view to the inner surface of the cap main body, the display recess is displayed smaller in the thin portion; When displaying on the liner surface, the visibility is reduced.
On the other hand, when the area of the display recess exceeds 50% of the area of the thin-walled part, the ratio of the area of the projections in the convex part of the mold exceeds 50%. In this case, since the resin is pressed with a relatively large surface constituted by the projection of the mold, the resin flow when pressing the resin is such that the area of the recess is less than 50% of the area of the thin portion It will decrease compared to the case.
On the other hand, in the method of manufacturing a cap with a liner according to the present invention, the area of the display recess is 3% or more and 50% or less of the area of the thin portion in the above plan view. While suppressing, it is possible to suppress the decrease of the resin flow.

The liner cap according to the present invention has a cap main body provided with a top surface and a cylindrical portion which is substantially suspended from the periphery of the top surface, and a liner provided on the inner surface of the top surface. A linerable cap capable of sealing the liner, wherein the liner is located at the outer edge of the surface of the liner and is surrounded by an annular seal closely contacting the mouth of the container and the seal; And a display recess formed on the surface of the thin portion, the area of the display recess being the thickness of the thin portion in a plan view to the inner surface of the cap body 3% or more and 50% or less of the area of the part.
Since the area of the display recess located in the thin portion of the liner cap of such a liner cap is 3% or more and 50% or less of the area of the thin portion, the consumer can easily recognize the display recess.

  According to the present invention, since the display formed on the liner is formed by the recess (recess for display), for example, the liner is configured as compared to the case where the display formed on the liner is formed by the projection. The amount of resin can be reduced, and the manufacturing cost of the liner cap can be reduced. Further, since the mold has a protrusion projecting from the convex portion, when the resin is pressed by the mold, the molten resin can be smoothly flowed to the outside (seal portion side) by the protrusion, so the liner It is possible to increase the yield of the attached cap.

It is the principal part side view which fractured a half of a liner cap of an embodiment of the present invention. It is an arrow A top view of a cap with a liner shown in FIG. It is an explanatory view showing a manufacturing process of a cap with a liner in this embodiment. It is a figure which shows the metal mold | die which shape | molds the sealing layer of the liner in this embodiment. It is an enlarged view which expands and shows a part of process of pressing molten resin in this embodiment with a metal mold | die. It is sectional drawing which shows the sealing layer of the liner in this embodiment, and the cross section of a sliding layer.

Hereinafter, embodiments of a method of manufacturing a cap with a liner and a cap with a liner according to the present invention will be described with reference to the drawings.
The liner cap of this embodiment is, for example, a pill fur proof cap (PP cap) attached to the mouth of an aluminum or aluminum alloy (metal) bottle can (a container according to the present invention) of 38 mm diameter and sealed. ) And the cap 3 with liner.

  1 and 2 show the cap 3 with a liner before attaching to a bottle can, and the cap 3 with a liner is formed into a cup shape by forming a plate material of aluminum or aluminum alloy coated on the inner and outer surfaces. And a liner 5 provided on the inner surface of the cap body 4. The cap main body 4 includes a top surface portion 41 and a cylindrical portion 42 which is substantially suspended from the periphery of the top surface portion 41.

The liner 5 is formed so as to abut on the opening (not shown) of the bottle can when the bottle can is closed by the liner cap 3 and to seal the inside of the bottle can. The liner 5 is disposed on the inner surface side of the top surface portion 41 of the cap body 4, and the sliding layer 51 sliding on the inner surface of the top surface portion 41 and the sliding layer 51 directly or an intermediate layer such as a barrier layer. The multi-layer structure is formed of a sealing layer 52 that is laminated via the sealing layer 52 and is softer than the sliding layer 51 and has a smaller outer diameter.
The sliding layer 51 is formed in a disk shape of polypropylene or the like. The sealing layer 52 is formed of an elastomer resin or the like softer than the sliding layer 51 and has a sealing function. As shown in FIG. 2, the sealing layer 52 is formed in a circular shape coaxial with the sliding layer 51 and smaller in diameter in plan view than the sliding layer 51. The sealing layer 52 is formed of an annular thick seal portion 54 in close contact with the mouth of the bottle can and a thin wall portion 55 formed on the inner side of the seal portion 54 and thinner than the seal portion 54. There is. In addition, although mentioned later in detail, as shown in FIG. 2, the recessed part 56 for displays is formed in the thin part 55. As shown in FIG.

The cylindrical portion 42 of the cap main body 4 has a cylinder upper portion 44 and a cylinder lower portion 45 which are divided up and down via slits 43 formed intermittently in the circumferential direction on the lower end surface thereof, and between adjacent slits 43 A plurality of bridges 43a are formed to connect the cylinder upper portion 44 and the cylinder lower portion 45.
Further, as shown in FIGS. 1 and 2, a plurality of hook portions having a plurality of knurled recesses 11 arranged in the circumferential direction in the vicinity of the top surface portion 41 of the cylinder upper portion 44 and an opening 12 for releasing the internal pressure at the time of opening. 13 are formed. An uneven surface is formed on the outer peripheral surface of the cylindrical portion 42 by arranging the knurled recess 11 and the hook portion 13 at an interval, thereby increasing the frictional resistance with the finger gripping the liner cap 3 at the time of opening. And can be easily opened.

  The hook portion 13 is a portion formed by pressing the upper portion divided by the opening portion 12 of the cylindrical portion 42 radially inward, and locks the liner 5 disposed on the top surface portion 41. Therefore, the distance from the top surface portion 41 to the radially inward end of the hook portion 13 is set to a distance larger than the thickness of the sliding layer 51. The inscribed circle C (see FIG. 2) formed by each hook portion 13 is set smaller than the outer diameter of the sliding layer 51 of the liner 5, and this sliding layer 51 is the hook portion 13 and the top surface portion. The liner 5 is supported by the hook portion 13 and attached to the cap body 4 by being disposed between the inner surface and the inner surface 41. The thickness of the liner 5, the outer diameter of the sliding layer 51 constituting the liner 5, the outer diameter of the sealing layer 52, and the like are determined according to the dimensions of the cap body 4.

Next, a method of manufacturing the liner cap 3 of the present embodiment will be described with reference to FIG.
[Painting process]
First, the inner and outer surfaces of the plate member 40 forming the cap body 4 are coated. Usually, a size coat and a top coat are applied to the surface on the inner side of the cap body 4, a size coat is printed on the surface on the outer side as needed, and then a top coat (gloss) is applied.

[Cap body molding process]
Then, a lubricant is applied to the painted plate 40 as required, and punched into a cup shape by a press to form the cap main body 4 having the top surface portion 41 and the cylindrical portion 42. Further, a plurality of hook portions 13 having an opening along the circumferential direction of the cylindrical portion 42 and the knurled recess 11 are respectively formed. At this time, processing of the bridge 43 a and the like is also performed on the lower portion of the cylindrical portion 42.

[Liner Forming Process]
The liner forming step includes a sliding layer forming step of forming the sliding layer 51 and a sealing layer forming step of forming the sealing layer 52 on the sliding layer 51. Details will be described below.
(Sliding layer forming process)
A sheet-like sliding layer 51 made of polypropylene (PP) or the like formed in a disk shape in advance is disposed on the inner surface of the top surface portion 41 of the cap main body 4. The peripheral edge portion of the sliding layer 51 is formed larger than the inscribed circle C (see FIG. 2) of the hook portion 13. For this reason, the peripheral edge portion of the sliding layer 51 is supported by the hook portion 13 and provided on the inner surface of the top surface portion 41 in a non-adhesive state without being removed from the cap main body 4.

  In the method of manufacturing the cap 3 with a liner in the present embodiment, the sheet-like sliding layer 51 formed in a disk shape in advance is disposed on the top surface portion 41 of the cap main body 4. The sliding layer 51 may be provided in the cap body 4 by an in-shell mold method in which a hard resin such as polyethylene is supplied to the inner surface of the top surface portion 41 and molded using a mold. In this case, the inner surface of the top surface portion 41 may be subjected to adhesion prevention measures in advance.

(Sealing layer forming process)
The sealing layer 52 supplies a predetermined amount of soft resin such as an elastomeric resin extruded and melted from the extruder to the center of the upper surface of the sliding layer 51 in a state where the sliding layer 51 is formed in the cap main body 4 (dropping) It is formed by molding the molten resin R2 by pressing with a mold M2 for molding.
As shown in FIGS. 3 and 4, the mold M2 for molding is a cylindrical guide G2, a punch P2 provided so as to be able to move forward and backward in the guide G2, and a pedestal D1 on which the cap main body 4 is placed. The sealing layer 52 is formed by the inner peripheral surface of the tip of the guide G2 and the pressing surface (surface) of the tip of the punch P2. The outer diameter of the guide G2 is set to be smaller than the inscribed circle C (see FIG. 2) of the hook portion 13, and the tip of the hook portion 13 is for the mold M2 when the mold M2 (guide G2) is inserted. By acting as a guide, centering (positioning) of the mold M2 with respect to the cap body 4 disposed on the pedestal D1 is performed. Note that such a guide G2 is provided with a spring S1 that presses and urges the guide G2 in the distal direction, and the biasing force of the spring S1 presses the surface of the sliding layer 51 in the cap body 4 by the guide G2. Form the outer peripheral edge of the cavity space for forming the sealing layer 52 on the sliding layer 51.

Here, the pressing surface of the punch P2 (mold) is, as shown in FIG. 4, an annular recess P20 for forming an annular seal portion 54, and a thin portion 55 having a smaller thickness than the seal portion 54. And a cylindrical convex portion P21 for forming the The convex portion P21 is located inside the annular concave portion P20, and on the surface of the convex portion P21, a projection P22 for forming the concave portion for display 56 in the thin portion 55 is formed to protrude from the surface. .
In addition, in FIG. 2, although the processus | protrusion P22 has shown planar view with a mere rectangle, it is made into shapes, such as a house mark and a character, in fact.

Then, the sealing layer 52 supplies (drops) a certain amount of soft resin such as elastomer extruded and melted from the extruder to the center of the sliding layer 51 supported by the cap main body 4, and the surface of the sliding layer 51 The molten resin R2 disposed in the above is immediately pressed by the cooled punch P2.
Specifically, when pressing of the molten resin R2 is started by the punch P2 in a state where the outer peripheral portion of the sliding layer 51 is pressed by the guide G2, as shown in FIG. The protrusion P22 protruding from the surface contacts the molten resin R2. Then, when the punch P2 moves further in the direction approaching the sliding layer 51, the molten resin R2 flows radially outward as shown by the arrow in FIG. 5 by the pressing force of the punch P2. That is, in the present embodiment, since the protrusion P22 is provided, the molten resin R2 is spread outward in the radial direction by the protrusion P22.

  Thereafter, when the punch P2 further moves in the direction in which the punch P2 approaches the sliding layer 51, the molten resin R2 pushed and spread by the projection P22 flows further outward by the convex portion P21. Then, when the punch P2 moves in the direction closest to the sliding layer 51, the molten resin R2 circulated to the outside by the protrusion P22 and the convex portion P21 reaches the inner side surface of the guide G2 and the annular recess P20, The molten resin R2 is filled in the entire area surrounded by the pressing surface of the punch P2. By being cooled in this state, a circular sealing layer 52 having a small diameter and coaxial with the sliding layer 51 is formed, and the liner 5 composed of the sliding layer 51 and the sealing layer 52 is formed.

On the surface portion of the liner 5 (sealing layer 52) formed by such a step, as shown in FIG. 6, an annular seal portion 54 and the seal portion 54 are formed by the annular recess P20 and the projection P21 of the punch P2. And a thin-walled portion 55 surrounded by the Further, in the thin portion 55, a display concave portion 56 corresponding to the protrusion P22 protruding from the convex portion P21 is formed.
In this case, in the sealing layer 52, the thickness dimension L2 of the seal portion 54, the thickness dimension L3 of the thin portion 55, and the thickness dimension L4 of the display recess 56 have a relationship of L2>L3> L4. That is, the thickness dimension of the sealing layer 52 becomes larger as it goes outward from the center of the sealing layer 52 in plan view.
Although the specific dimensions of these are not particularly limited, L2 = 0.7-1.0 mm, L3 = 0.25-0.3 mm, L4 = 0.15-0.25 mm, and the sliding layer 51 The thickness dimension L1 is 0.2 to 0.5 mm.

Then, as shown in FIG. 2, the area of the display recess 56 is set to 3% or more and 50% or less of the area of the thin portion 55 in a plan view on the inner surface of the cap main body 4.
Here, when the area of the display recess 56 is less than 3% of the area of the thin portion 55, the display recess 56 is displayed small in the thin portion 55, so for example, a house mark etc. When displaying on the thin portion 55, the visibility of the consumer is reduced.
On the other hand, when the area of the display recess 56 exceeds 50% of the area of the thin portion 55, the ratio of the area of the projection P22 in the projection P21 of the punch P2 exceeds 50%. In this case, the surface formed by the projections P22 of the punch P2 becomes large, and the molten resin R2 is pressed by the relatively large surface, so the resin flow when the molten resin R2 is pressed is the display The area of the recess 56 is reduced compared to the case where the area of the thin portion 55 is less than 50%.
For this reason, in the present embodiment, the area of the display recess 56 is set to 3% or more and 50% or less of the area of the thin portion 55.

In the present embodiment, the sliding layer 51 and the sealing layer 52 are completely adhered at the time of molding by selecting a material, but in order to further increase the adhesive force, after the sliding layer 51 is disposed A surface treatment process such as corona discharge treatment, glow discharge treatment, plasma treatment, anchor coating treatment, adhesive application and the like may be added to the surface of the sliding layer 51.
The cap with liner 3 manufactured by the above manufacturing process is subjected to capping processing in a state of covering the mouth of the bottle can, and a bottle can with cap (not shown) is formed.

  In the liner cap 3 of the present embodiment, the thickness dimension L4 of the display recess 56 in the thin portion 55 is smaller than the thickness dimension L3 of the thin portion 55, so the display recess 56 is configured by the protrusion. Compared to the case where the liner 5 is formed, the amount of resin that constitutes the liner 5 can be reduced, and the manufacturing cost of the liner cap 3 can be reduced.

  In addition, since the mold (punch P2) used in the liner forming step of the present embodiment has the protrusion P22 protruding from the convex portion P21, the gold in which the concave portion for display is formed on the convex portion P21 As compared with the case of using a mold, the flow of resin during molding can be smoothed to increase the yield of the liner cap 3.

The present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.
For example, in the above embodiment, although the cap can and the liner cap attached to the bottle can have been described, the container of the cap container in the present invention is not limited to the bottle can, In addition to bottle cans, containers such as glass bottles and PET bottles are also included.

Reference 3 3 cap with liner 4 cap body 5 liner 41 top surface 51 sliding layer 52 sealing layer 54 sealing portion 55 thin wall portion 56 display recess P 2 punch (mold)
P21 convex part P22 protrusion R2 molten resin

Claims (3)

A cap with a liner having a cap body including a top surface portion and a cylindrical portion substantially suspended from the peripheral edge of the top surface portion, and a liner provided on the inner surface of the top surface portion, which can seal the mouth of the container. A method of manufacturing,
An annular seal portion closely contacted to the mouth of the container by molding in which the mold is pressed against the molten resin supplied into the cap body, a thin portion surrounded by the seal portion, and the surface of the thin portion A liner forming step of forming a liner having a display recess formed in the above.   The method according to claim 1, wherein the area of the display recess is 3% or more and 50% or less of the area of the thin-walled portion in plan view on the inner surface of the cap body. . A cap with a liner having a cap main body provided with a top surface and a cylindrical portion substantially suspended from the peripheral edge of the top surface, and a liner provided on the inner surface of the top surface, which can seal the mouth of the container. There,
The liner is located at the outer edge of the surface of the liner and is in the form of an annular seal closely contacting the mouth of the container;
A thin portion surrounded by the seal portion and having a smaller thickness than the seal portion;
And a display recess formed on the surface of the thin portion;
The liner cap according to claim 1, wherein the area of the display recess is 3% to 50% of the area of the thin-walled portion in plan view on the inner surface of the cap body.

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