WO1998026991A1

WO1998026991A1 - Synthetic resin container lid having tamper evident characteristics

Info

Publication number: WO1998026991A1
Application number: PCT/JP1997/004649
Authority: WO
Inventors: Yoshihiro Kaitsuka
Original assignee: Japan Crown Cork Co., Ltd.
Priority date: 1996-12-17
Filing date: 1997-12-17
Publication date: 1998-06-25
Also published as: EP0913334A4; EP0913334B1; DE69726735T2; KR19990082645A; CN1106329C; CN1213348A; DE69726735D1; EP0913334A1; KR100621295B1; JPH10175656A; JP3847868B2

Abstract

A synthetic resin container lid having tamper evident characteristics includes axial direction breakage means which is disposed at a tamper evident skirt portion and a slit continuously extending from the upper end of the tamper evident skirt portion to its substantially lower end. A first high strength bridge portion is disposed on one of the sides of the upper end of the axial direction breakage means in a circumferential direction, and a second high strength bridge portion is disposed on the other side in the circumferential direction so that, when the container lid is fitted to the mouth/neck portion of the container, the tamper evident skirt portion is not expanded at the portion at which the axial direction breakage means exists.

Description

Specification

Synthetic resin container lid with tamper-evident properties

Technical field

The present invention relates to a synthetic resin applied to a container for storing beverages and the like, wherein a male thread and a locking jaw located below the male thread are formed on the outer peripheral surface of the mouth and neck. More particularly, the present invention relates to a synthetic resin container lid having a tamper-evident characteristic (a characteristic in which traces remain when the container lid is operated in order to make a mistake). Background art

As is well known, an external thread is formed on the outer peripheral surface of the mouth and neck portion and a locking jaw located below the external thread is formed on a glass or synthetic resin container for a soft drink or the like. Applicable container lids include, for example, Japanese Patent Publication No. 58-321203, Japanese Patent Publication No. 62-18421, Japanese Patent Publication No. Synthetic resin container lids having tamper-evident properties, which are disclosed in JP-A-6-54544 and JP-A-8-80957, are widely used in practice. Such a container lid has a circular top wall and a contact wall hanging from the top wall. The skirt wall is formed with a circumferential breaking means extending in the circumferential direction, and the skirt wall is divided into a main portion above the circumferential breaking means and a tamper-evident hem below the circumferential breaking means. Has been done. On the inner peripheral surface of the main part of the skirt wall, there is formed a female thread cooperating with a male thread formed on the mouth and neck of the container. Locking means cooperating with a locking jaw formed on the mouth and neck of the container is formed on the inner peripheral surface of the tamper evidence hem. The circumferential breaking means includes a plurality of bridging portions which are arranged at intervals in the circumferential direction and connect the tamper-evident hem portion to the main portion of the skirt wall. One of the sections is a high-strength bridge with a large cross-sectional area. An axial breaking means is formed at the foot of the tamper evidence. The axial breaking means may be based on a score formed by reducing the thickness of the material or a slit containing discontinuities (by completely cutting the material in its thickness direction or by cutting the material during molding). The groove is formed by not existing in the entire thickness direction.

When attaching the container lid to the mouth and neck of the container and sealing it, fit the container lid on the mouth and neck. Rotate in the closing direction, and then screw the female screw on the container lid into the male screw on the mouth and neck. The container lid is lowered in accordance with the progress of the screw engagement between the male thread and the female thread, and the locking means of the container lid elastically climbs over the locking jaw of the mouth and neck and locks the lower surface thereof. I will be forced. To open the mouth and neck of the container, rotate the container in the opening direction. In this case, the female screw of the container lid is moved along the male screw of the mouth and neck, and the screw is released, so that the container lid is raised in accordance with the rotation in the opening direction. . However, since the locking means formed on the skirt of the evening evidence is locked on the locking jaw of the mouth and neck, the hem of the tamper-evident is prevented from rising. As a result, stress is generated in the circumferential rupture means, and the bridge in the circumferential rupture means breaks except for one high-strength bridge. Furthermore, the following behavior is intended to be generated: That is, the score at the axial breaking means formed at the tamper-evident foot is broken, or the discontinuous portion of the slit is broken, and the force, and thus the evening-foot dent, is unfolded in a belt shape. Accordingly, the locking of the locking means with the locking jaw is released, and after that, the entire container lid is lifted in accordance with the rotation in the opening direction and detached from the mouth and neck.

Thus, according to the experience of the present inventors, the following problems exist in the conventional container lid as described above. That is, when the mouth and neck of the container is opened, the score in the axial breaking means formed on the tamper hem bottom is broken, or the discontinuous portion of the slit is broken, and the tamper The force at which the hem of the dent is intended to be unfolded in the form of a band A single high-strength bridge in the circumferential breaking means breaks instead of breaking the discontinuous part of the score or slit in the axial breaking means Therefore, the non-continuous part of the score or slit remains without being broken, so that the hem of the tamper-evident, which is in the form of an endless ring, is completely separated from the main part of the skat wall, and the mouth of the container is opened. The other part of the container lid is removed from the mouth and neck, leaving an endless annular tamper-evident hem at the neck. In the event of such a situation, the end of the tamper-evident in an annular endless form should be cut with appropriate cutting tools in view of the so-called material collection of waste or in order to reuse the container. It is necessary to separately perform the work of unrolling and removing from the mouth and neck of the container.

In order to solve the above-mentioned problems in the conventional container lid, the tamper- It is contemplated that the axial breaking means disposed on the portion comprises a slit extending continuously from the upper end of the tamper-evident hem to substantially the lower end. Thus, when opening the mouth and neck of the container, if the bridging part of the circumferential breaking means is broken except for one high-strength bridging part, the tamper-evident hem is inevitably band-shaped. Therefore, the entirety of the container lid is sufficiently released from the mouth and neck of the container. However, if the axial breaking means provided on the tamper-evident hem is simply constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper-evident hem, the mouth and neck of the container will not be provided. When attaching the container lid, especially when the means for locking the container lid elastically crosses over the locking jaw of the mouth and neck, the tamper-evident hem may be located in the area where the means for breaking in the axial direction exists. There is a tendency for an unacceptable and unacceptable situation in which at least some of the plurality of bridges in the circumferential breaking means are broken due to this.

Disclosure of the invention

Therefore, a main object of the present invention is to provide a structure in which the axial breaking means provided on the tamper dent hem is constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper dent hem. If the bridging part in the circumferential breaking means is broken except for one high-strength bridging part, the tamper-evident hem will inevitably expand in a belt shape, but the container When the container lid is attached to the mouth and neck, the evening skirt is expanded at the portion where the axial breaking means exists, and due to this, of the plurality of bridging portions in the circumferential breaking means. An object of the present invention is to provide a new and improved synthetic resin container lid in which at least some of them are prevented from being broken.

In order to achieve the above-mentioned main object, in the present invention, two of the plurality of bridging portions are made to be high-strength bridging portions having a large cross-sectional area, and these two high-strength bridging portions are It is disposed on both sides of the upper end of the axial breaking means, which is composed of a slit extending from the upper end of the tamper evidence to the substantially lower end, and one of the high-strength bridging sections is located at the upper end of the axial breaking means or is The one high-strength bridging portion extends from one end close to the one circumferential direction and the other high-strength bridging portion extends from the upper end of the axial breaking means or from one end close to the other circumferentially. That is, according to the present invention, as a synthetic resin container lid for achieving the above-mentioned main object, a male thread and a locking jaw located below the male thread are provided on the outer peripheral surface of the mouth and neck. A tamper-evident synthetic resin container applied to a container with

A top wall and a skirt wall hanging down from the top wall, wherein the skirt wall is formed with a circumferential breaking means extending in a circumferential direction, and the skirt wall is formed more than the circumferential breaking means. An upper main portion and a tamper-evident hem portion lower than the circumferential breaking means, and an inner peripheral surface of the main portion of the contact wall has the male screw of the neck portion. A female thread cooperating with the ridge is formed, and a locking means cooperating with the locking jaw of the neck portion is formed on the inner peripheral surface of the tamper-evident hem, and the circumferential break is formed. The means includes a plurality of bridging portions disposed circumferentially spaced apart and connecting the tamper-evident hem to a main portion of the wall, and One is the first high-strength bridge having a large cross-sectional area, and the tamper-evident hem is provided with an axial breaking means. In resin container closure,

The axial breaking means comprises a slit extending continuously from the upper end of the tamper-evident hem to the substantially lower end, and the plurality of bridging portions are connected to the first high-strength bridging portion. In addition, the first high-strength bridge and the second high-strength bridge have a large cross-sectional area, and the first high-strength bridge and the second high-strength bridge have a circumferential direction. The first high-strength bridging portion is disposed on both sides of the breaking means, and extends from the upper end of the axial breaking means or one end in a circumferential direction from one end adjacent thereto, and the second high-strength bridging portion is provided on the second height. The strength bridging portion extends from the upper end of the axial breaking means or from one end close thereto to the other circumferential direction,

The female thread is screwed onto the male thread, and the locking means is locked to the locking jaw, whereby the female thread is attached to the neck portion, and the female thread and the male thread are screwed. When the joint is released and detached from the neck portion, at least one of the first high-strength bridge portion and the second high-strength bridge portion is broken,

A synthetic resin container lid is provided.

The cross-sectional area of the first high-strength bridge is larger than the cross-sectional area of the second high-strength bridge. When removing from the department The second high-strength bridging portion is broken, but the first high-strength bridging portion remains without being broken, and the tamper-evident hem is unfolded in a belt shape to form the locking jaw. Conveniently, the locking means is unlocked to the part, and the entire container lid including the tamper-evident hem is detached from the neck. Cross-sectional area of the first high strength bridging portion is 1.5 0 to 4.5 0誦is ^2, cross-sectional area of the second high strength bridging portion 0s. 8 0 to 2.2 0誦² is preferred. Preferably, the first high-strength bridging portion is located in the axial direction when viewed in the direction of rotation of the container lid when the female thread and the male thread are unscrewed and detached from the neck. Located in front of the rupture means, the second high-strength bridge is located behind the axial rupture means. The one end of the first high-strength bridge and the one end of the second high-strength bridge are spaced apart from the upper end of the axial breaking means by 1.0 to 3.0 O mm. Preferably, it is located. In a preferred embodiment, the tamper-evident hem has a thin curl extending from the lower end thereof, and the slit constituting the axial breaking means extends partially or completely into the thin curl. I did not put it out.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a front view, partly in section, of a preferred embodiment of a container lid constructed according to the present invention.

FIG. 2 is a cross-sectional view taken along line A-A in FIG.

FIG. 3 is a partial front view showing a modification of the axial breaking means.

FIG. 4 is a front view, partially in section, showing a state where the container lid shown in FIG. 1 is attached to the mouth and neck of the container.

FIG. 5 is a partial cross-sectional view showing a modification of the first high-strength bridge.

FIG. 6 is a partial cross-sectional view showing a modified example of the first high-strength bridge and the second high-strength bridge.

FIG. 7 is a partial cross-sectional view showing another modified example of the first high-strength bridge and the second high-strength bridge.

FIG. 8 is a partial cross-sectional view showing still another modified example of the first high-strength bridge and the second high-strength bridge.

FIG. 9 shows another preferred embodiment of a container lid constructed according to the present invention, FIG.

FIG. 10 is a partial cross-sectional view taken along line BB in FIG.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of a synthetic resin container lid configured according to the present invention will be described in more detail with reference to the accompanying drawings.

FIG. 1 illustrates a preferred embodiment of a synthetic resin container lid constructed according to the present invention. The container lid, generally designated by reference numeral 2, which can be made of a suitable synthetic resin such as polypropylene or hard polyethylene, has a circular top wall 4 and a substantially cylindrical scat wall hanging from the periphery of the top wall 4. 6 is provided. The skirt wall 6 is formed with a circumferential breaking means 8 (the circumferential breaking means 8 will be described in more detail later), and the skirt wall 6 has a main portion 10 above the circumferential breaking means 8. The outer peripheral surface of the main portion 10 of the skirt wall 6, which is divided into the tamper-evident hem portion 12 below the circumferential breaking means 8, has an outer diameter in the vicinity of the lower end thereof, and downward. A gradually increasing conical portion 14 is formed. The lower end of the main portion 10 of the skirt wall 4, that is, the portion below the truncated cone portion 14 and the outer peripheral surface of the tamper-evident hem portion 12 following this, also have a slightly downward outer diameter. Has a conical shape that gradually increases. In a portion above the conical portion 14 on the outer peripheral surface of the main portion 10, a concave-convex shape 16 for preventing slipping of a finger hung thereon is formed. A female thread 18 is formed on the inner peripheral surface of the main part 10. The female thread 18 is formed with a notch 20 extending in the axial direction at intervals in the circumferential direction. The notch 20 constitutes a so-called air passage when the mouth and neck of the container is opened. An annular ridge 22 is formed on the inner peripheral surface of the main portion 10 at the upper end thereof. In a space defined by the annular ridge 22 and the inner surface of the top wall 4, a sealing liner 124 formed separately from the main body of the container lid 2 is provided. Such a sealing liner 24 can be conveniently formed by supplying a softened and molten synthetic resin material to the inner surface of the top wall 4 and compressing the synthetic resin material with a pressing tool. The synthetic resin material for the sealing liner 124 is preferably a relatively soft synthetic resin such as soft polyethylene. At the upper part of the inner peripheral surface of the tamper-evident hem portion 12, an annular shoulder surface 26 facing downward is formed. A plurality of flap pieces 28 are formed on the inner peripheral surface of the tamper-evident hem portion 12 at equal intervals in the circumferential direction below the force and the annular shoulder surface 26. . As will be apparent from the description below, the flap piece 28 constitutes a locking means to be locked to a locking jaw formed on the mouth and neck of the container. Each of the flap pieces 28 has a base edge 30 connected to the inner peripheral surface of the tamper-evident hem 12 and the closure of the container lid when the container lid 2 is attached to the mouth and neck of the container. It is inclined in the direction opposite to the rotational direction, ie, clockwise when viewed from above in FIG. 1, and protrudes inward in the radial direction. The base edge 30 of each of the flap pieces 28 also extends downward in a direction opposite to the closing rotation direction of the container lid 2. At the lower end of the tamper-evident foot 12, a thin curl 32 extending radially inward in an arc is attached.

Continuing the description with reference to FIG. 2 in conjunction with FIG. 1, the tamper-evident foot 12 has an axial breaking means 34 formed thereon. It is important that the axial breaking means 34 be composed of a slit that continuously extends from the upper end of the tamper-evident foot portion 12 to the substantially lower end. In the illustrated embodiment, the slits constituting the axial breaking means 34 extend continuously from the upper end of the tamper-evident hem 12 to the upper end of the thin curl 32, but the thin curl 3 2 or not at all (slits partially extend into the thin curl 32 depending on the cutting error in the forming operation of the axial breaking means 34 described later). It may be in the form of extending or not extending at all). If desired, a slit constituting the axial breaking means 34 can be extended to the tip of the thin curl 32. The slit constituting the axial direction breaking means 34 does not intersect with the base edge 30 of the flap piece 28 formed on the inner peripheral surface of the tamper dent bottom 12, and the flap piece 28 does not cross. Preferably, they are located in between. If desired, the slits constituting the axial breaking means 34 may be somewhat inclined instead of extending substantially vertically (ie, substantially parallel to the central axis), for example, as shown in FIG. The flap piece 28 may extend substantially parallel to the base edge 30 of the flap piece 28 as described above. As can be clearly understood by referring to FIG. 2, the above-mentioned circumferential breaking means 8 includes a plurality of bridging portions 36 a, 36 b, Includes 36c and 36d. In the cross-sectional view in which the circumferential breaking means 8 is provided, in the area other than the bridging parts 36a, 36b, 36c and 36d, the main part of the skirt wall 6 The section 10 and the tamper-evident foot section 12 are preferably separated from each other by cutting. Therefore, the tamper-evident foot portion 12 is connected to the main portion 10 via the bridging portions 36a, 36b, 36c and 36d. A plurality of the bridging portions 36a are arranged at equal intervals in the circumferential direction (except for a region where the first high-strength bridging portion 36c mentioned later is arranged), and are substantially the same. It has a cross-sectional shape of. A plurality of the bridging portions 36 b are also arranged at equal intervals in the circumferential direction (except for the region where the first high-strength bridging portion 36 c described later is arranged), and are substantially the same. Has a cross-sectional shape of The same number of bridges 36 a and bridges 36 b are arranged, and each of the bridges 36 b is located in the middle of the adjacent bridge 36 a. The cross-sectional area of each of the bridges 36a is sufficiently small, and the cross-sectional area of each of the bridges 36b is slightly larger than the cross-sectional area of the bridge 36a, but sufficiently small. The bridges 36a and 36b can be easily broken. Bridge 36c is the first high-strength bridge with a large cross-sectional area. Bridge 36d is also the second high-strength bridge with a relatively large cross-sectional area. In FIG. 2, the first high-strength bridging part 36 c extends counterclockwise from one end located at a distance L 1 in the counterclockwise direction (one in the circumferential direction) from the upper end of the axial breaking means 34. The second high-strength bridging portion 36 d extends clockwise from one end of the axial breaking means 34 with an interval L 2 in the clockwise direction (the other circumferential direction) from the upper end. In order to ensure that the behavior described below is generated in the container lid 2 when attaching the container lid 2 to the mouth and neck of the container and when detaching the container lid 2 from the mouth and neck of the container The cross-sectional area A 1 of the first high-strength bridge 36 c is about 1.5 to 4.5 O ram ² , and the cross-sectional area A 2 of the second high-strength bridge 36 d is first smaller than the cross-sectional area of the high strength bridging portion 3 6 c (a 2 <a 1) 0. 8 0 to 2. 2 0 in the range of discussions about ² are preferred. Further, it is preferable that the intervals L1 and L2 are in the range of 1.0 to 3.0.

An example of the procedure for manufacturing the container lid 2 as described above will be described as follows. It is. First, the main body of the container lid 2 (that is, the portion excluding the sealing liner 124) is formed by compression molding or injection molding from an appropriate synthetic resin. In the molded container lid body, the circumferential breaking means 8 has not yet been formed, and the main part 10 of the skirt wall 6 and the tamper-evident hem 12 are crossed at the position of the circumferential breaking means 8. It is connected in all areas of the surface. Also, the thin curl 32 has not yet been curled, and extends substantially vertically downward as shown by the two-dot chain line in FIG.

Thereafter, the following cutting process is performed to form the circumferential breaking means 8. As can be clearly understood by referring to FIG. 1, the inner peripheral surface of the scuttle wall 6 also has an annular shoulder surface 38 that is slightly lower than the above-described annular shoulder surface 26 and faces downward. Has been established. Protrusions 40a and 40b extending from the annular shoulder surface 38 to a position slightly higher than the annular shoulder surface 26 are formed below the annular shoulder surface 38. A plurality of ridges 40a are arranged at equal intervals in the circumferential direction, and have substantially the same shape. The ridges 40b are also arranged at equal intervals in the circumferential direction, and have substantially the same shape. The number of the ridges 40a and the number of the ridges 40b are the same, and each of the ridges 40b is positioned between the adjacent ridges 40a. Protrusion 40a (the first high-strength bridge

(Except for the ridge 40a located in the area of 36c) defines the above-mentioned bridging part 36a,

40b (excluding the ridge 40b located in the area of the first high-strength bridge 36c) defines the bridge 36b. Therefore, the cross-sectional shape of the ridge 40a corresponds to the cross-sectional shape of the bridging portion 36a, and the cross-sectional shape of the ridge 40b corresponds to the cross-sectional shape of the bridging portion 36b. In the cutting step for forming the circumferential breaking means 8, first, only the angular region where the first high-strength bridge 36c and the second high-strength bridge 36d are present is left. The skirt wall 6 is gradually cut from its outer peripheral surface to its inner peripheral surface in the circumferential direction. The cutting blade used for such cutting does not substantially act on the ridges 40a and 40b, and the radially outer portions of the ridges 40a and 40b are partially cut for the sake of cutting. However, the main parts of the ridges 40a and 40b are left without being cut, and thus the bridges 36a and 36b are formed. Next, in the angular region where the first high-strength bridging portion 36c and the second high-strength bridging portion 36d are present, the thickness direction of the skat wall 6 from the outer peripheral surface of the skat wall 6 Up to a predetermined depth (to a depth of about half of the thickness in the illustrated embodiment), the cutting blade is operated to partially cut the skirt wall 6, and thus A first high-strength bridge 36c and a second high-strength bridge 36d are generated. As can be clearly understood by referring to FIG. 2, in the illustrated embodiment, one ridge 40a and one ridge 40b are the first high-strength bridges 36. Part of c is specified. Then, a cutting blade extending in the axial direction is caused to act on the tamper pin skirt portion 12, and is cut in the axial direction over the entire thickness direction up to the substantially lower end of the tamper ebident skirt portion 12, and the axial direction breaking means is provided. The slits that constitute 3 4 are formed.

After the above-described cutting step, a thin curl 34 is formed by applying a heating curl tool to the thin portion extending substantially vertically without being curled to form the thin curl shown in FIG. Next, the sealing liner is formed by the above-described molding process using a pressing tool, and the force, and thus the container lid 2 is completed.

FIG. 4 shows a state where the container lid 2 is attached to the mouth and neck portion 42 of the container as required. The mouth and neck portion 42 of the container, which can be formed of a suitable synthetic resin such as glass or polyethylene terephthalate, has a cylindrical shape as a whole, and has an external thread 44 and an external thread on its outer peripheral surface. An annular locking jaw 46 located below the ridge 44 is formed. After filling the container with appropriate contents such as soft drinks, the container lid 2 is attached to the mouth and neck 4 2. At this time, the container lid 2 is fitted over the mouth and neck portion 42, and the container lid 2 is rotated in the closing rotation direction, that is, clockwise as viewed from above in FIG. 18 is screwed into the male thread 44 of the mouth and neck portion 42, and the container lid 2 is lowered in accordance with the rotation. The flap pieces 28 formed on the tamper-evident hem portion 12 of the container lid 2 are sexually deformed and pass through the locking jaws 46 of the mouth and neck portion 42, and then elastically. It is restored and locked by the locking jaws 46. When the flap pieces 28 pass through the locking jaws 46, a radially outward force acts on the tamper-evident hem 12 and the tamper-evident hem 1 It is assumed that the slit constituting the axial breaking means 34 in 2 is not expanded. In view of the circumferential direction, the container lid 2 constructed according to the present invention has a first high-strength bridging portion 36c (FIG. 2) on one side of the slit when viewed from the circumferential direction. There is a second high-strength bridge 36d (Fig. 2) on the side, and the retaining action of the first high-strength bridge 36c and the second high-strength bridge 36d. This ensures that the slits do not undesirably expand, so that the bridges 36a and 36b ( Figure 2) is sufficiently reliably prevented from being broken. The sealing liner 124 disposed on the inner surface of the top surface wall 4 of the container lid 2 is brought into close contact with the top surface of the mouth-neck portion 42, thereby sealing the mouth-neck portion 42. .

When opening the mouth and neck portion 42 of the container, the container lid 2 is rotated in the opening rotation direction, that is, counterclockwise as viewed from above in FIG. As a result, the female thread 18 formed on the main part 10 of the cut wall 6 in the container lid 2 is moved along the male thread 44 formed on the mouth and neck 42 of the container. Therefore, the container lid 2 is raised with the rotation. However, the tamper-evident hem portion 12 of the container lid 2 has the flap pieces 28 formed on the inner peripheral surface thereof locked to the locking jaws 46 of the mouth and neck portion 46. Upward movement is prevented. Therefore, considerable stress is generated at the bridging portions 36a, 36b, 36c and 36d (Fig. 2) in the circumferential breaking means 8 provided on the skirt wall 6, and the force and the applied force are generated. Due to the stress, the bridges 36a and 36b, whose cross-sections are small enough, are broken, and the second high-strength bridge 36d is also broken. Further, the thin curl attached to the tamper-evident hem 12 is broken along the extension of the slit formed in the tamper-evident hem 12 (constituting the axial breaking means 34). Is done. Such a break of the thin curl 32 can be realized easily and reliably because the wall thickness is extremely thin. When the fracture is performed as described above, the tamper-evident hem that continues to be connected to the main part 10 of the scar wall 6 by the first high-strength bridging part 36 c remaining without being fractured. The part 12 is deformed into a form extending in an arc from the part where the first high-strength bridging part 36 c is present, and the flap pieces 28 are locked to the locking jaws 46 of the mouth and neck part 42. Is released. Thereafter, the entire container lid 2 including the tamper-evident hem 12 is raised with rotation, and the entire container lid 2 is detached from the mouth and neck portion 42. In the course of such opening operation, when the container lid 2 is raised slightly and the sealing liner 24 is separated from the top surface of the mouth and neck portion 42, the inside of the mouth and neck portion 42 is opened. The space between the top of the neck 42 and the sealing liner 24 and the cutout 20 (FIG. 1) formed in the female thread 18 of the container lid 2 communicate with the outside.

If the first high-strength bridging portion 36 d is accidentally broken during the opening operation as described above, the tamper-evident hem portion 12 separates from the main portion 10 of the skirt wall 6. The tamper-evident hem 12 is removed from the mouth and neck 4 2 except for the tamper-evident hem 12 of the container lid 2, but the tamper-evident hem 12 is left in the mouth and neck 4 2. However, since the axial breaking means 34 formed on the tamper-evident foot 12 is formed by a slit extending continuously from the upper end of the evening-evident foot 12 to substantially the lower end, cutting is performed. If a thin curl 32 is not broken along the extension of the slit without the need for a knife, etc., the curl will be broken and the tamper-evident hem 1 2 that will remain sufficiently easily 1 2 Can be disengaged from the mouth and neck 42.

FIG. 5 illustrates a modification of the first high-strength bridge. In the modified example shown in FIG. 5, the first high-strength bridging portion 1336 is formed by increasing the cross-sectional area of the first high-strength bridging portion 1336c to increase its strength. In Fig. 5c, at the left end, the tamper-evident foot 1 1 2 is not cut at all, and in Fig. 5, at the left end, the first high-strength bridge 1 36 c is the tamper-evident foot 1 1 2 exists over the entire thickness direction from the outer peripheral surface to the inner peripheral surface.

FIG. 6 illustrates a modified example of the first high-strength bridge and the second high-strength bridge. In the embodiment illustrated in FIG. 6, the tamper-evident foot 2 12 is completely absent in both the first high-strength bridge 2 36 c and the second high-strength bridge 2 36 d. Not cut, both the first high-strength bridging section 2 36 c and the second high-strength bridging section 2 36 d, tamper-evident hem 1 1 2 throughout their circumferential direction Exist over the entire thickness direction from the outer peripheral surface to the inner peripheral surface. On the other hand, the circumferential length of the first high-strength bridge 2 36 c and the second high-strength bridge 2 36 d is the first high-strength bridge 36 c shown in Fig. 2. And the second high-strength bridging portion is shorter than the circumferential length of 36 d. And one ridge 240b defines the first high-strength bridging portion 236c, which is located adjacent to and on the right side of the one ridge 240b. The ridge 240a does not specify the first high-strength bridge portion 236a, but the normal bridge portion 236a.

FIG. 7 illustrates another modification of the first high-strength bridge and the second high-strength bridge. In the embodiment shown in FIG. 7, the first high-strength bridging portion 336 c is not spaced from the upper end of the slit constituting the axial breaking means 334, 7 extends to the right in FIG. 7 from the upper end of the slit constituting the axial breaking means 3 3 4, and similarly, the second high-strength bridging section 3 36 d constitutes the axial breaking means 3 3 4 Axial breaking means without any distance from the upper end of the slit 3 3

In Fig. 7, the first high-strength bridging portion 336c and the second high-strength bridging portion 336d form They are adjacent to each other.

FIG. 8 illustrates yet another modification of the first high-strength bridge and the second high-strength bridge. The first high-strength bridging portion 436c of the embodiment shown in FIG. 8 is provided with no gaps with respect to the upper end of the slit constituting the axial breaking means 434. 4 3 4 extending to the right from the slits, one ridge 4

40b defines the first high-strength bridging portion 436c, but the ridge located adjacent to and on the right side of the ridge 4440b is the first high-strength bridge The first high-strength bridging part in the embodiment shown in FIGS. 1 to 4 in which the bridging part 436 c is not specified but the normal bridging part 436 a is specified. Different from 36 c. In addition, the second high-strength bridging part 436d shown in FIG. 8 is provided without any gap with respect to the upper end of the slit constituting the axial breaking means 434. 4 extends to the left from the slit that constitutes 4, and one ridge 44 a is the second high-strength bridge 4 3

6 d is different from the second high-strength bridging part 36 d in the embodiment shown in FIGS.

9 and 10 illustrate another preferred embodiment of a container lid constructed in accordance with the present invention. In the container lid 502 shown in FIG. 9 and FIG. 10, a sealing liner 152 is formed on the inner surface of the top wall 504. This sealed liner 5

Reference numeral 24 denotes an inner annular seal ridge which enters the mouth and neck of the container and is brought into close contact with the inner peripheral surface, and an outer annular seal ridge which is brought into close contact with the upper surface or the outer peripheral surface of the mouth and neck of the container. Contains 5 2 7 The locking means provided on the inner peripheral surface of the tamper-evident hem portion 5 12 is composed of an annular projecting piece 5 28 extending continuously in the circumferential direction. The annular protruding piece 528 extends upward from the base edge 5330 connected to the inner peripheral surface of the tamper-evident hem 512 inward in the radial direction. The annular projecting piece 528 has a slit 528 extending from the tip to the vicinity of the base edge. They are formed at intervals in the direction of the arrow. When forming the container lid 502 from an appropriate synthetic resin, in order to avoid forcibly removing the strength, the annular projecting piece 528 should be placed radially inward as shown by the two-dot chain line in Fig. 9. Conveniently, it is formed into a form extending downward, and after being removed from the mold, deformed to the state shown by the solid line. In an embodiment in which the locking means comprises an annular projecting piece 528 extending continuously in the circumferential direction, the axis at the tamper-evident foot 512, as can be understood by reference to FIG. It is preferable that the annular projecting piece 528 be formed with a slit extending continuously from the base edge to the tip end thereof by being aligned with the slit constituting the direction breaking means 534. Such a slit in the annular projecting piece 5 28 is used to cut the tamper-evident hem 5 12 by a cutting blade to form a slit constituting the axial breaking means 5 34. 8 can be conveniently formed by cutting. The configuration of the container lid 502 shown in FIGS. 9 and 10 is substantially the same as that of the container lid 2 shown in FIGS. If desired, instead of a circumferentially extending annular projecting piece 528 (or a plurality of circumferentially spaced flap pieces 28), a ratchet piece known to those skilled in the art can be used. Other suitable forms of locking means, such as, may also be provided on the inner peripheral surface of the tamper-evident hem 512.

In the container lid of the present invention, the axial breaking means provided on the tamper-edent hem portion is constituted by a slit extending continuously from the upper end to the substantially lower end of the tamper-evidence hem portion. If the bridging part in the circumferential breaking means is broken except for one high-strength bridging part when the container lid is removed from the mouth and neck of the tamper- The container is deployed and the entire container lid is released from the mouth and neck of the container. Even if all bridges, including the high-strength bridge, were broken, leaving the tamper-evident hem at the mouth and neck, and the rest of the container lid detached from the mouth and neck, Since the remaining hem of the tamper-evident is formed with a slit extending continuously from the upper end to the substantially lower end, it is troublesome to cut the tamper-evident hem with a cutting tool. It is possible to remove the residual tamper-evident hem from the mouth and neck sufficiently easily without any manipulation. On the other hand, when the container lid is attached to the mouth and neck of the container, it is arranged on both sides of the axial breaking means. The holding action of the first and second high-strength bridging portions sufficiently suppresses the tamper-evident hem from being expanded at the portion where the axial breaking means exists, and therefore, the circumferential breaking means. The breakage of at least some of the plurality of bridge portions in the above is sufficiently and reliably prevented.

Claims

The scope of the claims

1. Applied to a container having an external thread formed on the outer peripheral surface of the mouth and neck and a locking jaw positioned below the external thread, made of synthetic resin having tamper-evident characteristics Container s: Otsu, Atsu

It has a top wall and a skirt wall hanging down from the top wall, and the circumferential wall is formed with a circumferential breaking means extending in the circumferential direction. A main portion above the step and a tamper-evident hem portion below the circumferential breaking means, and an inner peripheral surface of the main portion of the skirt wall has the male screw of the neck portion. A female thread cooperating with the ridge is formed, and a locking means cooperating with the locking jaw of the neck portion is formed on the inner peripheral surface of the tamper-evident hem, and the circumferential break is formed. The means includes a plurality of bridging portions disposed circumferentially at intervals and connecting the tamper-evident hem to the main portion of the strut wall; One is the first high-strength bridge having a large cross-sectional area, and the tamper-evident hem is provided with an axial breaking means. In resin container closure,

The axial breaking means comprises a slit extending continuously from the upper end of the tamper-evident hem to substantially the lower end thereof, and the plurality of bridging portions are the first high-strength bridging portions. A second high-strength bridging portion having a large cross-sectional area in addition to the first high-strength bridging portion and the second high-strength bridging portion, wherein the first high-strength bridging portion and the second high-strength bridging portion The first high-strength bridging portion extends from the upper end of the axial breaking means or one end in the vicinity thereof to one side in the circumferential direction; The bridging portion extends circumferentially from the upper end of the axial breaking means or from one end close to the other in the circumferential direction,

A container lid made of synthetic resin, characterized in that:

2. The cross-sectional area of the first high-strength bridge is larger than the cross-sectional area of the second high-strength bridge. When you remove from the neck The second high-strength bridging portion is broken, but the first high-strength bridging portion remains without being broken, and the tamper-evident hem is unfolded in a belt shape to form the locking jaw. 2. The synthetic resin container lid according to claim 1, wherein the locking of the locking means to the part is released, and the entire container lid including the tamper-evident hem is detached from the mouth and neck.

3. The cross-sectional area of the first high-strength bridge is 1.5 to 4.5 thigh ² , and the cross-sectional area of the second high-strength bridge is 0.8 to 2.2. The synthetic resin container lid according to claim ^2, which is 0 mm2.

4. The first high-strength bridging portion is broken in the axial direction when viewed from the container rotating direction when the female screw and the male screw are unscrewed and detached from the neck portion. 4. The synthetic resin container lid according to claim 2, wherein the second high-strength bridging portion is located in front of the means, and is located behind the axial breaking means.

5. The distance between the one end of the first high-strength bridging portion and the-end of the second high-strength bridging portion is 1.0 to 3.0 thighs from the upper end of the axial breaking means. The synthetic resin container lid according to any one of claims 1 to 4, wherein

6. The tamper-evident hem is provided with a thin curl extending from the lower end thereof, and the slit constituting the axial breaking means is partially or not extended to the thin curl. Claim of the synthetic tree according to any one of claims 1 to 5