Structure for removing end ring of resin bottle cap and container having the same

Abstract

To provide a structure for removing an end ring of a resin bottle cap which prevents a barb body of the end ring screwed into a bottle body together with a cap body from being caught by a cut end face of a ring stop flange at the time of initial capping, and allows the end ring to be easily removed from the bottle body at the time of disposal, and a container having the same.SOLUTION: The present invention is characterized in that, for example, the effective guide zone size W1, which is the sum of the notch part size W2 of the guide flange notch part 151 and the non-barb part size W3 of the guide non-barb part 255, is designed to be the minimum size necessary for the removal guide inclined posture of the end ring 25 to appear, while the container-side indicator 31 is formed substantially at the center of the effective guide zone size W3, and the end-ring-side indicator 32 is formed to be shifted therefrom in the removing operation direction D, so that the end ring 25 can be removed even if the indicator 3 is slightly shifted.SELECTED DRAWING: Figure 12

Description

[Technical Field]

[0001] The present invention relates to an end ring removal structure for a plastic bottle cap, which allows the end ring remaining on the bottle body to be easily removed from the bottle body when opening the bottle cap of, for example, a PET bottle, and a container equipped with the same. This is a further improvement of a development (invention) that the applicant has already obtained a patent for (Patent No. 4560127). [Background technology]

[0002] Recently, so-called PET (polyethylene terephthalate) bottles, primarily made of polyethylene terephthalate (PET), have become popular as beverage containers. When collecting and recycling these bottles, it is desirable to collect them as a single material whenever possible. Thanks to public awareness campaigns, at least the cap itself and plastic wrap, which are made of different materials, are easily removable and are therefore often removed before collection. However, caps have end rings attached to the bottle body via a weakened section to allow the user to confirm whether the lid is open. Because removing these components is extremely tedious, bottles are almost always collected with the end rings still attached. In light of this situation, proposals have been made to facilitate end ring removal, as well as to improve the structure of the cap and bottle body. However, regarding hand tools, it is unrealistic to expect average households to have these tools, and they have not yet become widespread. Furthermore, few practical improvements to the container's structure that would allow for the current mass production of products have been proposed, and none have even appeared on the market.

[0003] Prior art related to the present invention includes Japanese Patent Application Laid-Open Publication No. 2006-232392, entitled "Bottle-shaped Resin Container with Cap, Allowing Easily Removing the Cap Circumferential Band from the Bottle Mouth" (see Patent Document 1). This technology incorporates a sloped notch in the upper flange of the ring retainer (the circumferential projection 8 of the bottle mouth), which prevents the end ring (the cap circumferential band) from slipping out. The end ring is fitted with a protrusion 13 that guides the end ring's return flap (projection 7) into the sloped notch. By rotating the end ring, the end ring can be removed from the upper flange of the ring retainer, starting from the notch. However, in this prior art, the end ring is sandwiched between the upper and lower ring retainer flanges, restricting overall deformation. Therefore, sufficient deformation to be guided by the notch is not achieved, or achieving this deformation requires a tremendous amount of force, resulting in the design failing to achieve its intended purpose. For this reason, the applicant attempted to develop a device that allows the end ring to be removed from the bottle body simply by tilting the position of the end ring, without assuming deformation of the end ring itself, and has already obtained a patent for this (Patent No. 4560127) (see Patent Document 2). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-232392 [Patent Document 2] Patent No. 4560127 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention was made as part of such developments, and is a further improvement and development of the invention of Patent Document 2, which allows the end ring to be removed simply by tilting its position. The technical objective of the present invention was to develop a new end ring removal structure and a container equipped with this structure, in which the barb of the end ring, which is screwed into the bottle body together with the cap body at the capping stage (initial closing) after filling with beverage, does not get caught on the notched end face of the ring retaining flange formed on the bottle body. [Means for solving the problem]

[0006] The end ring removal structure for a resin bottle cap according to claim 1 is as follows: In a structure in which an end ring attached to a bottle cap attached to a lid closing portion of a bottle body, which is separated from the cap body when the lid is opened and remains in a ring receiving portion of the bottle body, is detached and removed from the bottle body, The ring receiving portion is formed by a recess between the ring stopper upper flange and the ring stopper lower flange, and the ring stopper upper flange is open at the upper side at the guide flange cutout portion, The end ring is provided with a barb along its inner periphery to prevent it from coming off and abut against the ring retaining upper flange to remain in the ring receiving portion, and the circumferential barb is configured to be divided by a guide barb-free portion in a partial range where the barb is not formed, When removing the end ring, the guide barb-free portion and the guide flange cutout portion are placed adjacent to each other to set a fixed removal start point, and the restriction imposed by the ring stopper upper flange on the end ring is partially released, causing the end ring to assume a removal guide tilted posture at the start of its removal. The guide flange cutout portion has a pair of cutout end faces on both sides, and of these, the cutout end face that abuts the barb that passes through the guide flange cutout portion when the bottle cap is initially closed is characterized by having a corner removal portion formed by cutting off the corner.

[0007] The end ring removal structure for a resin bottle cap described in claim 2 satisfies the requirements of claim 1, as well as: The end ring is partially connected to the cap body at multiple points by bridge portions, which are components of the weakened portion, but in the portion without the guide barb, the number of bridge formation points is reduced compared to other portions, or the bridge portions are made thinner, or the bridge portions are eliminated altogether.

[0008] The end ring removal structure for a resin bottle cap described in claim 3 has, in addition to the requirements of claim 1 or 2, An indicator is formed between the end ring and the bottle body to indicate that a fixed removal start point has been set. In a fixed removal start point setting state where the guide flange cutout portion and the guide barb-free portion are adjacent to each other, the container side indicator is formed approximately in the center of the effective guide zone dimension, which is the sum of the cutout dimension of the guide flange cutout portion and the barb-free portion dimension of the guide barb-free portion, and the end ring side indicator is formed shifted from this position toward the removal operation direction.

[0009] The end ring removal structure for a resin bottle cap described in claim 4 has, in addition to the requirements of claim 1 or 2, The guide flange notch is characterized by being formed at the terminal end of a male thread formed on the lid closing portion of the bottle body.

[0010] The end ring removal structure for a resin bottle cap described in claim 5 has, in addition to the requirements of claim 1 or 2, The barb body is characterized in that the corners in a side view are formed in a rounded shape, and the cross-sectional shape of the free end of the barb body is also formed in a rounded tip.

[0011] The end ring removal structure for a resin bottle cap described in claim 6 has, in addition to the requirements of claim 1 or 2, The barb body adjacent to the non-guiding barb-equipped portion is characterized by a load-bearing reinforcement structure that keeps the end ring, which is pulled upward with a certain force as the cap body is opened, in the ring-receiving portion.

[0012] The container according to claim 7 comprises: A container having a bottle body and a bottle cap attached to a lid closing portion of the bottle body as main components, and having a structure for removing and removing an end ring from the bottle body when the lid is opened and remaining in a ring receiving portion of the bottle body, The ring receiving portion is formed by a recess between the ring stopper upper flange and the ring stopper lower flange, and a guide flange cutout portion is formed in a part of the ring stopper upper flange, and the guide flange cutout portion is open at the top, The end ring is provided on its inner circumferential side with a barb for preventing it from coming off, which abuts against the ring stopper upper flange for remaining in the ring receiving portion, and the barb is configured to be divided by a guide barb-free portion in a state where the barb is not formed in a part of the range. When removing the end ring, the guide barb-free portion and the guide flange cutout portion are placed adjacent to each other to set a fixed removal start point, and the restriction imposed by the ring stopper upper flange on the end ring is partially released, causing the end ring to assume a removal guide tilted posture at the start of its removal. The guide flange cutout portion has a pair of cutout end faces on both sides, and of these, the cutout end face that abuts the barb that passes through the guide flange cutout portion when the bottle cap is initially closed is characterized by having a corner removal portion formed by cutting off the corner. The above problems are solved by the means described in each claim. [Effects of the Invention]

[0013] First, according to the invention described in claim 1 or 7, when the bottle cap is initially closed, a corner removal portion is formed by removing the corner of the notch end face against which the barb that has passed through the guide flange notch portion abuts. Therefore, when the barb passes through the guide flange notch portion during initial closing, it does not get caught on the notch end face, preventing the barb from being torn apart during initial closing. Furthermore, when removing the end ring from the bottle body at the time of disposal, the barb body will not get caught on the cut-out end face, and the end ring can be removed (dismounted) smoothly.

[0014] Furthermore, according to the invention described in claim 2, in the guide barb-free portion that does not form a barb body, the number of bridge formation locations is reduced compared to other portions, or the bridge portion is made thinner, or the bridge portion is eliminated, thereby increasing the separability of the end ring (separability from the cap body) in that portion and enabling the end ring to be reliably separated from the cap body.

[0015] According to the invention of claim 3, the end ring can be reliably removed from the cap body even if the container-side indicator and the end ring-side indicator are slightly misaligned. In other words, the end ring must not accidentally come off during use of the container. To achieve this, it is desirable to design each of them so that the effective guide zone dimension, which is the sum of the dimensions of the notched portion and the non-barbed portion, is the minimum width dimension necessary to cause the end ring to assume the inclined position for removal. However, this design requires that the container-side indicator and the end ring-side indicator be perfectly aligned, otherwise the end ring cannot be placed in the inclined position for removal. In other words, even a slight misalignment can prevent the end ring from being removed. Therefore, with the above-described embodiment of the present invention, the end ring can be removed from the bottle body even if the indicators are slightly misaligned, and the end ring can be removed almost reliably even if the consumer positions the indicators somewhat loosely.

[0016] Furthermore, according to the invention described in claim 4, the guide flange cutout portion is formed at the end of the male thread formed on the lid closing portion of the bottle body, making it easier to ensure a passage for the barb body to escape (a longer distance can be ensured), and the end ring can be pushed up (passed through the ring retaining upper flange) more easily and reliably.

[0017] Furthermore, according to the invention described in claim 5, even if a person touches the inside of the end ring removed from the container with their fingertips, cuts or the like are unlikely to occur.

[0018] According to the invention of claim 6, the end ring can be reliably retained in the ring receiving portion when the cap body is opened. That is, the end ring is required to have strength to withstand a certain amount of upward force when the cap body is opened, and the presence of the non-guiding barb portion reduces this strength. However, in this invention, a load-bearing reinforcement structure is provided on the barb body adjacent to the non-guiding barb portion, so the end ring can be reliably retained in the ring receiving portion. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a partially cutaway perspective view showing a partially enlarged view of a container to which the present invention is applied. [Figure 2] 10A and 10B are enlarged perspective views of the lid closing portion of the container, showing a state in which the end ring is fitted into the bottle body and a state in which the end ring is separated from the bottle body. [Figure 3] 1A and 1B are longitudinal side views showing the state in which the bottle cap is attached to the bottle body and the state in which it is separated from the bottle body, and FIG. 1C is a cross-sectional plan view of the end ring portion. [Figure 4] FIG. 4 is an enlarged cross-sectional view showing the state in which the bottle body and the end ring are engaged with each other. [Figure 5] 10A to 10C are side views sequentially showing the state in which the end ring is removed from the bottle body. [Figure 6] 10 is an explanatory view showing another embodiment in which a corner is removed when forming a corner removed portion on the cutout end face of the guide flange cutout portion. FIG. [Figure 7] FIG. 10 is an explanatory diagram showing yet another embodiment of the same. [Figure 8] 10 is another embodiment of an indicator for aligning the bottle body and the end ring when removing them. [Figure 9] FIG. 10 is a partially enlarged perspective view showing an embodiment in which an operation instruction display for removing an end ring from a container is provided. [Figure 10] This is an explanatory diagram showing, in stages, how the free end of the barb (barb flap) gradually moves inward to avoid the corner of the notched end face as the end ring rotates counterclockwise during the initial opening of the bottle cap. [Figure 11] FIG. 10 is a vertical cross-sectional side view of a bottle body (lid closing portion) in which a guide flange cutout portion is formed at the terminal end of the male thread. [Figure 12] 10A to 10C are three skeletal side views showing the case where the container side indicator and the end ring side indicator are formed offset from each other. [Figure 13]This is a projection diagram (a) showing a side view of an example of a configuration that eliminates sharp parts of the barb body, as well as a cross-sectional diagram (b) taken along line AA in this diagram (a) and a cross-sectional diagram (c) taken along line BB in this diagram (b). [Figure 14] 10 is an explanatory diagram showing three types of reinforced structures (load-bearing reinforced structures) of adjacent barb flaps located next to the guide barb-free portion. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention is embodied in the following examples, and also includes various methods that can be improved within the scope of the technical concept. [Example]

[0021] The present invention will be described in detail below with reference to the illustrated embodiments. Reference symbol C denotes a container to which the present invention is applied. This container is broadly composed of a bottle body 1 and a bottle cap 2. Between the two, an indicator 3 is provided, which serves as a guide for removing an end ring 25, which will be separated from the bottle cap 2 (described later). The bottle body 1 is, for example, a transparent plastic container known as a PET bottle, primarily made of polyethylene terephthalate (PET). A separate wrap 10 is attached to the bottle so that it is wrapped around the body 11. The wrap 10 and bottle cap 2 are typically made of a different type of resin from the bottle body 1, and are preferably removed and collected when the bottle body 1 is collected. The bottle cap 2 is also collected for the purpose of recycling the cap resin.

[0022] First, the bottle body 1 will be described in more detail. The body 11 of the bottle body 1 has a suitable volume of approximately 100 to 2000 cc, such as a rectangular, cylindrical, or hexagonal cylindrical shape. A cap-closing portion 12 is formed at the top of this body 11. The cap-closing portion 12 generally refers to the area from the shoulder of the body 11 upwards where the bottle cap 2 is placed. The upper end of the cap-closing portion 12 is open to a spout 13, and a male thread 14 is appropriately formed downward from near the spout 13. The male thread 14 may have any suitable shape, such as a continuous spiral or a partially interrupted shape. An upper ring-retaining flange 15 is formed below the male thread 14. A lower ring-retaining flange 16 is formed below and opposite the upper ring-retaining flange 15, and the diameter of the lower ring-retaining flange 16 is typically larger than that of the upper ring-retaining flange 15. This ring stopper lower flange 16 is used as an example of a forming portion, and is where the container-side indicator 31 of the indicator 3 is provided. The ring stopper upper flange 15 and the ring stopper lower flange 16 form a substantially recessed area between them, which is referred to as the ring receiving portion 17. The height dimension of this ring receiving portion 17 is set to allow some play so that the end ring 25 (described later) can move up and down slightly while retaining it. In addition, the area above the ring stopper upper flange 15 and below the male thread 14 is the area where the end ring 25 (described later) first attempts to come out, and this area is referred to as the ring coming out portion 18.

[0023] The ring stopper upper flange 15 has the following configuration. First, as shown enlarged in FIGS. 1 and 4, a guide flange cutout portion 151 is formed in a portion of the ring stopper upper flange 15. Of the pair of cutout end faces 152, 153 constituting the guide flange cutout portion 151, at least the cutout end face 152 on the removal operation direction side of the end ring 25 forms a guide inclined surface 152f, for example, toward the removal operation direction (indicated by arrow D) of the end ring 25. Note that the removal operation direction D refers to the direction of rotation, since the end ring 25 is rotated to remove it after being placed in the guide inclined position, as described below. In this embodiment, the direction is clockwise (the arrow points left in FIG. 5), but it can also be set counterclockwise. In this embodiment, the other opposing cutout end face 153 also forms an inclined surface that is approximately parallel to the cutout end face 152 on the removal operation direction side. In the embodiment shown in Figures 1 to 5, the opposing surfaces of these notched end faces 152, 153 are not parallel but rather open outward to some extent. In particular, the ridge of notched end face 152 is designated as guide edge 152e, and its outermost end is designated as top edge 152t. The opening width of guide flange notch 151 is designated as notch dimension W1, and the vicinity of the lower end of notched end face 152 on the removal operation direction side is designated as guide starting point P for removing end ring 25. Furthermore, container-side indicator 31 on ring retainer lower flange 16 is provided at the location where guide flange notch 151 is formed, as shown in Figure 4(a) as an example. Furthermore, as shown in the full drawing, the ring retaining upper flange 15 is open at the top at the guide flange cutout portion 151, but the ring receiving portion 17 side does not have a protrusion like that seen in Patent Document 1.

[0024] In the present invention, as shown in the enlarged view of FIG. 1 , for example, a corner 152c of the cutout end surface 152 of the guide flange cutout portion 151 (the end surface on the side of the end ring 25 in the removal operation direction) is removed to form a corner-removed portion 152r. Regarding how to remove the corner 152c of the cutout end surface 152, i.e., how to form the corner-removed portion 152r, the corner-removed portion 152r may be formed as a flat surface (a straight line in a plan view) or a curved surface (a curve such as an arc in a plan view), or an appropriate combination of these may be used to form the corner-removed portion 152r. Alternatively, the corner-removed portion 152r may be formed by tilting the guide inclined surface 152f toward the user when viewing the guide flange cutout portion 151 substantially from the front, thereby removing the corner 152c. Incidentally, the cutout end surface 152 on which the corner removal portion 152r is formed is the end surface against which the barb body 250 abuts after passing through the guide flange cutout portion 151 during initial capping (capper), as will be described later. The reason for forming the corner removal portion 152r on the cutout end surface 152 is to prevent the barb body 250 of the bottle cap 2 (end ring 25) from getting caught on (interfering with) this corner portion 152c during initial capping or when the end ring 25 is removed from the bottle body 1, as will be described later.

[0025] Next, we will explain the bottle cap 2 that fits onto the bottle body 1. This cap has a female thread 22 formed on the inside of the cap body 21, which threads onto the male thread 14 to tighten and secure the bottle cap 2. The cap body 21 is formed integrally with the end ring 25 via a weakened portion 23. Specifically, the weakened portion 23 is formed by molding the two integrally at multiple connection positions (referred to as bridge portions 23A) scattered at regular intervals. When the cap body 21 is turned in the loosening direction during use, the end ring 25 is prevented from rising by the ring stopper upper flange 15, while the cap body 21 rises. This rise breaks the bridge portion 23A, a component of the weakened portion 23, and the cap body 21 can be opened with the end ring 25 remaining in the ring receiving portion 17. Of course, the separation structure between the end ring 25 and the cap body 21 is not limited to this type, and there are also structures in which the rotation of the end ring 25 is prevented when the cap is opened, and then the two are separated at the weakened portion 23 by twisting the cap body 21 to open it.

[0026] An example of the end ring 25 will be described below. First, the end ring 25 has a circular ring body 25A and a barb body 250 for preventing the ring from slipping out on the inside thereof. In this embodiment, the barb body 250 is formed of a plurality of barb flaps 251. That is, as shown in Figures 1, 2, and 3, the barb flaps 251 are formed at seven locations on the inside of the ring body 25A, dividing the circumference into eight equal parts, for example, and their free ends 252 point upward while maintaining a natural state of being slightly tilted inward. The base side of the barb flaps 251 is injection molded integrally with the ring body 25A.

[0027] Each of these barb flaps 251 has a barb flap width dimension WF, and is disposed adjacent to an adjacent barb flap 251 while maintaining an inter-barb gap 254 therebetween. A guide-barb-free portion 255 is formed in a portion thereof, as if one barb flap 251 had been removed. That is, in this embodiment, due to the presence of the inter-barb gap 254, the barb flaps 251 have a configuration in which a plurality of element pieces are intermittently arranged circumferentially, and the guide-barb-free portion 255 is formed in a portion in which one element piece of the barb flap 251 has been removed. Of course, the barb body 250 may be configured such that the barb flaps 251 are continuous at a portion other than the guide-barb-free portion 255, without providing the inter-barb gap 254. The width of the guide barb-free portion 255 is defined as the barb-free portion dimension W2, which in this embodiment is the barb flap width dimension WF plus twice the inter-barb flap gap dimension WG. Furthermore, as shown in FIGS. 1 and 5(a-1), the barb-free portion dimension W2 is set to be the same as or slightly shorter than the notch dimension W1. Furthermore, when viewed from a plan view, each barb flap 251 is formed by dividing the circumference into eight equal parts, so in this embodiment, the barb-free portion dimension W2 is set to an angle of approximately 45° + α (see FIG. 3(c)). The pitch dimension per barb flap 251 is defined as the barb flap pitch dimension WP, which is essentially the sum of the barb flap width dimension WF and the inter-barb flap gap dimension WG. In addition, in describing the removal operation of the end ring 25, the barb flaps 251 are also denoted as f1, f2, ... fn in order of their position following the guide barb-free portion 255, and the barb flap 251 immediately following the guide barb-free portion 255 is also referred to as the guide start flap f1. Of the indicators 3 described above, the end ring side indicator 32 can be provided at the location where this guide start flap f1 is formed. In this embodiment, when the container side indicator 31 and the end ring side indicator 32 are aligned, the guide flange cutout portion 151 and the guide barb-free portion 255 are set adjacent to each other (this is the removal start fixed point setting state described below, and is not visible from the outside). Furthermore, since the end ring 25 is separated from the cap body 21 by the operation described above, in the above-mentioned guide barb-free portion 255 where the barb flap 251 is not formed, it is preferable to reduce the number of bridge formation points in the weakened portion 23, or to thin or eliminate the bridge portion 23A of the guide barb-free portion 255, thereby more reliably causing the weakened portion 23 to rupture during initial opening.

[0028] Furthermore, when the barb body 250 is of a divided type, it is not a movable type like the barb flap 251 described above, but rather a fixed type with multiple protrusions, or even a movable type with the swing (movement) direction set to the circumferential direction of the ring receiving portion 17 in a neck-fastening manner. There is also a lip-shaped type in which the barb body 250 is not divided, but is continuous with the inner peripheral surface of the ring main body 25A, and the upper edge is free. However, in any form, the intended operation can be achieved by providing the guide non-barb portion 255.

[0029] The present invention has the basic structure described above, and its operating mode will be explained below, but first, the functions required of the bottle cap 2 will be explained. Here, the end ring 25 generally remains attached to the bottle body 1 until the beverage is consumed, and the basic functions required of the bottle cap 2 will be explained based on this premise. Of course, since the present invention is designed so that the end ring 25 can be removed from the bottle body 1, the timing for removing the end ring 25 does not necessarily have to be when the bottle is discarded after the beverage is consumed; for example, the end ring 25 can be removed following the opened cap body 21 when the bottle is initially opened to consume the first beverage. The bottle cap 2 must have different functions required for each situation, from manufacturing to disposal, and it is necessary to comprehensively satisfy these different functions. These functions are (1) function at initial closure (manufacturing), (2) function at transportation and display, (3) function at initial opening, (4) function at the time of drinking, (5) function at reclosure, (6) function at reopening, and (7) function at the time of disposal.

[0030] First, (1) the initial capping (manufacturing) function requires that the bottle cap 2 with the end ring 25 can be quickly and securely attached to the bottle body 1, and in particular, that the end ring 25 can smoothly enter the ring receiving portion 17. (2) The transport and display function requires reliable capping and the ability to maintain the end ring 25. (3) The initial uncapping function requires that the end ring 25 smoothly separate from the cap body 21 and remain securely in the ring receiving portion 17. (4) The drinking function requires that the end ring 25 remain in the ring receiving portion 17 and not change position so as to come into contact with the drinker's lips. (5) The recapping function requires that the end ring 25 generally approaches the lower circumferential surface of the cap body 21, preventing soiling or other damage to that area. (6) The recapping function requires that the end ring 25 completely prevents the end ring 25 from coming loose when the cap body 21 is uncapped. And (7) as a disposal function, the end ring 25, which had previously been required to be securely attached, can be removed from the bottle body 1 extremely easily.

[0031] Here, the purpose and effect of forming the corner removed portion 152r on the cutout end surface 152 will be described. First, the initial capping step (capping) is the stage in which the bottle cap 2 is attached to the bottle body 1 filled with a beverage and capped. At this time, the end ring 25 is connected to the bottle cap 2 (cap body 21) at the bridge portion 23A, which is a component of the weakened portion 23, as described above. Therefore, the end ring 25, integrated with the bottle cap 2, is accommodated in the ring receiving portion 17, climbing over the ring stopper upper flange 15. During this initial capping step, the end ring 25 (i.e., the return flap 251) is also pushed in from above while rotating clockwise (while rotating in the tightening direction) together with the bottle cap 2. During this operation, if the corner 152c is present on the notch end face 152 of the guide flange notch portion 151, the return body 250 (return flap 251) being pushed downward while rotating clockwise would get caught on the corner 152c (this has actually been confirmed by a demonstration experiment by the applicant). That is, in the present invention, since the guide flange cutout portion 151 exists just before the barb flap 251 reaches the cutout end surface 152, when the barb flap 251 passes through the guide flange cutout portion 151, the force (action) restricting the barb flap 251 from the inside is temporarily released, and the free end 252 (upper end) of the barb flap 251 tilts toward the inner periphery, and the barb flap 251 in this state gets caught on the corner portion 152c. Of course, if this catch is strong (if the barb flap 251 gets strongly caught on the corner portion 152c), the bridge portion 23A of the weakened portion 23 may be torn off even during the initial plugging operation. Naturally, if such a situation were to occur, the end ring 25 would not be able to fulfill its function as described above, so in the present invention, a corner removal portion 152r is formed on the cutout end face 152 to eliminate the corner portion 152c, thereby preventing such a situation.

[0032] Furthermore, by forming the corner removal portion 152r on the cutout end face 152, the return flap 251 does not get caught on the corner portion 152c even during disposal, and the end ring 25 can be smoothly removed from the ring receiving portion 17 (can be moved onto the ring stopper upper flange 15). Conversely, if the cutout end face 152 had a corner portion 152c, the return flap 251 would get caught on the corner portion 152c when removing the end ring 25 from the bottle body 1 (when turning it clockwise for the first time), and the end ring 25 would not be able to smoothly move over the ring stopper upper flange 15.

[0033] Incidentally, it has been confirmed through a demonstration experiment by the present applicant that when the guide flange notch 151 is formed in the ring stopper upper flange 15 as in the present invention, the above-mentioned corner portion 152c is unnecessary. That is, during initial opening, as shown in FIG. 10 for example, the end ring 25 rotates counterclockwise (loosening direction) together with the cap body 21 (because it is connected by the bridge portion 23A of the weakened portion 23) and gradually rises together with the cap body 21. At this time, the upper free end 252 of the barb flap 251 abuts against the lower smooth surface of the ring stopper upper flange 15, and this abutment force gradually increases as the end ring 25 rises. Therefore, as the end ring 25 rises, the barb flap 251 gradually tilts inward. Viewed from above, this operation causes the position of the free end 252 of the barb flap 251 to gradually move inward. For this reason, during initial opening, the free end 252 of the barb flap 251 does not abut against the corner 152c. Therefore, if the guide flange notch 151 is formed in the ring stopper upper flange 15 as in the present invention, the corner 152c would be unnecessary.

[0034] Next, a removal operation for removing the end ring 25 from the bottle body 1 will be described. First, in the initial state, as shown in Fig. 5 as an example, the indicator 3 is used to align the container-side indicator 31 with the end ring-side indicator 32 (see Figs. 5(a-1) to (a-5)). For the sake of explanation, Figs. 5(a-1) to (a-5) show the side of the cylindrical lid closing part 12 in a form that is stretched out in a plane. In this initial preparation state, the guide flange cutout portion 151 and the guide barb-free portion 255 are adjacent to each other, creating a fixed removal start point setting state. When viewed from the end ring 25, this state is one in which there is no upward restriction by the ring stopper upper flange 15. That is, as shown in FIG. 5(a-1), in the range where the guide flange cutout portion 151 is provided, the end ring 25 is allowed to move upward, despite the presence of the barb flap 251. On the other hand, in the area where the ring stopper upper flange 15 is located adjacent to the guide flange cutout portion 151 on the removal operation direction side, the guide barb-free portion 255 is present on the end ring 25 side, so the end ring 25 is allowed to move upward even in this range.

[0035] This range is the effective induction zone Z, and its dimensions are shown as the effective induction zone dimension W3. The effective induction zone dimension W3 is the sum of the cutout dimension W1 and the non-barb dimension W2, and the state in which the effective induction zone Z is formed is achieved only when the container side indicator 31 and the end ring side indicator 32 are aligned, reaching the removal start fixed point setting state. Furthermore, when the range of the effective induction zone Z is expressed in angle in a plan view, it is approximately 100° because the cutout dimension W1 is 45° + α. When the effective guide zone dimension W3 is ensured in this manner, the end ring 25 can easily assume the removal-guiding tilted position. Specifically, as shown in FIGS. 5(a-2) and 4(b-2), when the indicator 3 is pressed upward with a finger or the like, the ring-retaining upper flange 15 for restricting the end ring 25 is not present in this area, allowing the end ring 25 to move upward. Furthermore, adjacent to this area in the removal operation direction, the end ring 25 is provided with a guide-barb-free portion 255 and does not have a barb flap 251. Therefore, even if the ring-retaining upper flange 15 is present above this area, the end ring 25 is still allowed to move upward. As a result, as shown in FIGS. 4 and 5, while the end ring 25 is held in the ring receiving portion 17, the vertical dimensional allowance of the ring receiving portion 17 allows the end ring 25 to easily assume a basically tilted position, i.e., the removal-guiding tilted position, despite microscopic deformation. Since the end ring 25 is pushed up in this manner, for example, by forming a guide flange cutout portion 151 at the terminal end of the male thread 14 as shown in Figure 11, it becomes easier to ensure an escape path for the return flap 251 (a longer distance can be ensured), and the end ring 25 can be pushed up more easily and reliably.

[0036] Regarding the inclination of the end ring 25, as shown in FIGS. 4(b-1) to (b-6) and 4(c-1) to (c-2), in the steady state, the end ring 25 rests on the ring-retaining lower flange 16, with its inclination angle at 0°. Even in the steady state, the end ring 25 has some play (vertical backlash) due to the vertical clearance within the ring-retaining portion 17. As shown by the phantom line in FIG. 4(b-1), this play causes the end ring 25 to tilt, resulting in an inclination angle β0. Furthermore, in the removal-guided tilted position, the inclination angle β1 becomes even larger than the inclination angle β0. As the end ring 25 continues to be removed, the inclination angles β2, β3, β4, and β5 further increase, as shown in FIGS. 4(b-2) to (b-6). The operational behavior at this time is described below. Note that the inclination angles β0 to β5 in FIG. 4 are exaggerated for clarity.

[0037] Then, when this removal guide inclined posture is obtained, if the end ring 25 is further moved clockwise as indicated by the arrow D in Figure 5(a-3) by operating the fingertip (arrow D points to the left when shown in a plan view), the first guide start flap f1 of the return flaps 251, i.e., the guide start flap f1 following the guide barb-free portion 255, will rest on the guide start point P on the notched end face 152 of the ring stopper upper flange 15 and will shift upward, guided by the guide inclined surface 152f (or, more microscopically, the guide edge 152e) (see Figure 5(a-3) and Figures 4(b-3) to (b-4)). 5(a-4) to (a-5) and 4(b-2) to (b-5), by continuing this process, the subsequent barb flaps f2, f3, ... fn (f7 in this embodiment) of the barb flap 251 move sequentially from the ring receiving portion 17 to the ring exit portion 18, as if diagonally crossing the ring retaining upper flange 15. At this time, the boundary position where the end ring 25 itself naturally moves from the ring receiving portion 17 to the ring exit portion 18 side is the position of the top edge 152t on the guiding edge 152e, and as shown in FIGS. 5(a-1) to (a-3), a slight rotation from the state where the removal start fixed point is set can obtain a tendency for the end ring 25 to move toward the ring exit portion 18 side. Looking more closely, in the enlarged cross-sectional view taken along line III-III in Figure 5(a-3), the area passing through the maximum diameter portion of the ring retainer upper flange 15, i.e., the top edge 152t, is represented by the top edge line 125tL, and the line passing through the free end 252 of the barb flap 251 is represented by the free edge line 252L. As long as the free edge line 252L of the barb flap 251 passes the top edge line 152tL, the end ring 25 tends to slip through in the direction of arrow A in the figure. As a result, the end ring 25 is reliably removed by simply tilting its position with almost no deformation. Even though the end ring 25 has slipped out of the ring receiving portion 17, the lower inner periphery of the end ring 25 still covers the ring retainer upper flange 15, and as shown in Figure 5(a-5), it appears as if it has not been completely removed. After that, it can be removed by turning it counterclockwise, for example, in the direction of loosening of the male thread 14. For this type of removal method, an instruction sign 4 can be provided on the bottle body 1 or the wrap 10 as shown in Figure 9, which will make consumers aware of the proper removal process of the end ring 25 and encourage them to separate and collect the end rings.

[0038] The above describes the operation for removing the end ring 25. The following describes the relationship between the functions required of the bottle cap 2 in each situation and the removal structure of the end ring 25. First, during design, by designing the respective formation positions of the male thread 14 and the female thread 22 in advance, it is possible to prevent a fixed removal start point setting state from occurring during initial capping. In addition, considering that the cap body 21 rotates when separating the cap body 21 and the end ring 25 during initial capping, the stopping position of the end ring 25 during initial capping, i.e., the position where the tightening of the bottle cap 2 together with the cap body 21 is completed, needs to be such that the end ring side indicator 32 is offset from the container side indicator 31 by an appropriate angle toward the loosening side of the bottle cap 2. These conditions and positional relationships are defined as the initial capping state and the initial capping position, respectively. Furthermore, the offset between the container-side indicator 31 and the end-ring-side indicator 32 in this state is defined as the initial offset angle θS. As shown in Figure 3(c), the initial offset angle θS in the initial capping state could theoretically be about 1°, but in practice is set in the range of about 5° to 90°. If the bottle cap 2 is then turned in the loosening direction (counterclockwise) from the initial capping position, and even if the end ring 25 separates midway, assuming the end ring 25 also rotates, the angle at which the end ring 25 reaches the removal start fixed point setting state is defined as the capping margin angle θM. This capping margin angle θM is approximately 270° to 355°. For many bottle caps 2, separation of the cap body 21 and the end ring 25 is completed within the range of the capping margin angle θM.

[0039] This state fulfills the (1) initial closure (manufacturing) function, (2) transportation and display function, and (3) initial unclosure function required of the bottle cap 2, ensuring reliable closure and preventing the end ring 25 from falling off during initial unclosure. Once unclosure is complete, the removal-guiding tilted posture, which is the condition for the end ring 25 to come off, cannot be achieved unless the bottle body 1 and the end ring 25 are in a very limited state known as the fixed removal start point setting state, i.e., the relationship between the bottle body 1 and the end ring 25 is within a 360° range of 0°, allowing for a backlash error, of approximately 1° to 2°. Therefore, this state fulfills the (4) drinking function, (5) reclosure function, and (6) reopening function required of the bottle cap 2, ensuring that the end ring 25 remains securely in the ring receiving portion 17.

[0040] Other Examples The present invention is based on the above-described embodiment as one basic technical concept, but the following modifications can be considered. First, in the basic embodiment described above, when forming the corner removed portion 152r on the cutout end surface 152 of the guide flange cutout portion 151, a form in which the corner 152c of the cutout end surface 152 is cut off in a straight line in a plan view has been mainly shown. However, the formation of the corner removed portion 152r is not limited to this, and it is also possible to form the corner removed portion 152r by cutting off the corner 152c in a curved line that is an arc in a plan view (a so-called R-surface), as shown in Figures 6(a-1) to 6(a-2). Furthermore, for example, an embodiment shown in Figures 6(b-1) to 6(b-2) is also possible, which is a form in which the corner 152c is cut off in a relatively long straight line in comparison with the basic embodiment described above. 6(a-1)-(a-2) and (b-1)-(b-2), the cutout end surface 152 is formed straight without being inclined when viewed from above, and the present invention can also employ such an embodiment (an embodiment without the guide inclined surface 152f). In particular, in Figures 6(b-1)-(b-2), before the corner 152c of the cutout end surface 152 is removed (cut off), the guide flange cutout portion 151 is simply formed in a direction perpendicular to the forming direction of the ring stopper upper flange 15, i.e., in the vertical direction, or in other words, the cutout end surfaces 152, 153 are formed in the normal direction of the cylindrical lid closing portion 12.

[0041] Furthermore, when removing the corner portion 152c, it is also possible to form a corner removal portion 152r by viewing the guide flange cutout portion 151 substantially from the front, for example, as shown in Figure 7, and removing the corner portion 152c by tilting the guide inclined surface 152f toward the front. Note that Figure 7 above shows the state of the guide flange cutout portion 151 in an oblique view, a plan view, and a front view before and after the corner portion 152c is removed. In particular, in the plan view of Figure 7(c), the arrow indicates the state in which the guide inclined surface 152f is inclined toward the front, and in the plan view of Figure 7(b) and the oblique view of Figure 7(a), the shape before the corner portion 152c is removed is indicated by a dashed line.

[0042] Furthermore, the embodiment shown in Figure 8 is another example of the indicator 3, a recessed indicator 3R. Specifically, a portion of the ring retainer lower flange 16 is cut out to form the container-side indicator 31R, while a portion of the end ring 25 is also cut out to form the end ring-side indicator 32R. By combining these, the removal operation start state, i.e., the removal start fixed point setting state, is achieved. This configuration allows the end ring 25 to be easily indicated by touch with the fingertip, making it easy for visually impaired people to operate, thus providing a product that complies with so-called universal design. In particular, it is desirable for the end ring-side indicator 32R to have a recessed shape that tapers upward in front view and protrudes upward (like a visor) in cross section. In this configuration, the fingertip that detects the removal start fixed point setting state of the indicator 3R is easily engaged to slide the end ring 25 upward, allowing the end ring 25 to be placed in the removal-guiding tilted position and immediately begin the removal operation. Although the above-described embodiments of the indicator 3 are preferable, it is also possible to simply guide the removal start fixed point setting state and set the position at which the end ring 25 is pushed upward at the start of removal to a different position.

[0043] Furthermore, the embodiment shown in FIG. 9 is a display for informing consumers of the structure for removing the end ring 25 of the present invention, and by displaying such a display, separate resource collection is more actively encouraged. Furthermore, in the above explanation, the bottle body 1 is exemplified by the most popular so-called PET bottle, but the present invention can also be applied to other materials, such as conventional glass containers.

[0044] Furthermore, while the container C is in use (for example, when the beverage filled in the container C is drunk little by little in several sittings), the bottle cap 2 is repeatedly opened and closed, and therefore, as described above, the end ring 25 must not come off accidentally while the container C is in use. To achieve this, it is desirable to design each of the above-mentioned effective guidance zone dimension W3, i.e., the sum of the notched portion dimension W1 and the non-barb portion dimension W2, to be the minimum width dimension required to create the end ring 25's removal-guiding inclined posture. However, on the other hand, this type of design can lead to a situation where the end ring 25 cannot be removed and placed in the induced tilted position unless the container side indicator 31 and the end ring side indicator 32 are perfectly aligned (even a slight misalignment may make it impossible to remove the end ring 25).

[0045] Furthermore, the operation of removing the end rings 25 is premised on the assumption that it will be performed by ordinary consumers, not by a specific worker, and not all consumers will necessarily align the indicators 3 perfectly. That is, even if a consumer intends to align the indicators 3, it is possible that they will actually be out of alignment, which may prevent the end rings 25 from being removed. For this reason, it is preferable to make it possible to remove the end rings 25 even if the indicators 3 are slightly out of alignment, and such an embodiment will be described below. First, in the basic embodiment described above, when the guide flange cutout portion 151 and the guide non-flange portion 255 are adjacent to each other (removal start fixed point setting state), the container side indicator 31 and the end ring side indicator 32 are set to coincide, but this indicator 3 is shifted. More specifically, as an example, as shown in Figure 12(a), when the guide flange cutout portion 151 and the guide non-barb portion 255 are adjacent (removal start fixed point setting state), the container side indicator 31 is formed approximately in the center of the sum of the cutout portion dimension W1 and the non-barb portion dimension W2 (effective guide zone dimension W3), and the end ring side indicator 32 is formed shifted from this by several mm (for example, about 1 to 2 mm) toward the removal operation direction. When the indicator 3 is formed in this manner, if the end ring 25 (the part where the indicator 3 is formed) is pushed up in the state shown in Figure 12(a), the guide flange cutout portion 151 and the guide barb-free portion 255 will be adjacent to each other, so naturally the end ring 25 can be removed and the indicator can be placed in the guided inclined position.

[0046] Furthermore, when the indicator 3 is formed offset in this manner, when the container-side indicator 31 and the end-ring-side indicator 32 are aligned, an example state such as that shown in Figure 12(b) is obtained, and even if an attempt is made to push the end ring 25 (the portion where the indicator 3 is formed) upward, the barb flap f2 is prevented from rising by the ring stopper upper flange 15 (the guide start flap f1 and the guide barb-free portion 255 rise). However, since this pushing-up operation rotates the end ring 25 in the removal operation direction as described above, during this rotation the barb flap f2 matches the guide flange cutout portion 151 and can pass through the ring stopper upper flange 15 (the end ring 25 can finally be removed from the bottle body 1).

[0047] On the other hand, when the end ring-side indicator 32 is shifted to the opposite side (opposite side of the removal operation direction) relative to the container-side indicator 31, an example of the state shown in Figure 12(c) is reached, and even if an attempt is made to push the end ring 25 (the portion where the indicator 3 is formed) upward, the barb flap f2 is prevented from rising by the ring stopper upper flange 15 (the guide start flap f1 and the guide barb-free portion 255 can rise). However, in this case as well, the end ring 25 is rotated in the removal operation direction as a result of the pushing-up operation, and during this rotation the barb flap f2 fits into the guide flange cutout portion 151 and can pass through the ring stopper upper flange 15 (the end ring 25 can finally be removed from the bottle body 1).

[0048] Furthermore, with regard to the return flap 251 of the end ring 25, the corner portion of the free end 252 has conventionally been nearly perpendicular when viewed from the side (when viewed from the front of the return flap 251), and has a thin, sharp tip when viewed in vertical cross section (see FIG. 4(a)). Even though the return flap 251 is sharp in this way, it has not been considered a particular problem in the past, since consumers have rarely removed the end ring 25, but have instead collected and discarded it. However, when the end ring 25 can be easily removed as in the present invention, it is desirable to form the barb flap 251 in a cut-proof shape CP, as shown in Fig. 13, so that the free end 252 and its corners are not sharp and cause cuts or other damage. Specifically, the corners of the barb flap 251 are formed into smooth curved surfaces, and more specifically, in a side view, the corners are rounded (see Fig. 13(a)), and the cross-sectional shape of the free end of the barb flap 251 also has a rounded tip (see Fig. 13(b)), thereby forming the cut-proof shape CP.

[0049] Furthermore, in the present invention, it is essential that the end ring 25 has a certain range where the barb body 250 is not provided, that is, a guide-use non-barb portion 255. On the other hand, the barb body 250 is required to remain on the bottle body 1 side when the end ring 25 is first opened as a tamper evidence. In other words, the end ring 25 is required to be strong enough to withstand a certain amount of upward force when the cap body 21 is opened, but the presence of the guide-use non-barb portion 255 reduces this strength. For this reason, in the present invention, a load-bearing reinforcement structure LF is adopted for the barb flap 251 (referred to as the adjacent barb flap 251N) adjacent to the guide barb-free portion 255. Specifically, for example, as shown in FIG. 14(a), a load-bearing reinforcement structure LF can be adopted in which the overall thickness is made thicker than that of the other barb flaps 251. Alternatively, as shown in FIG. 14(b), a load-bearing reinforcement structure LF can be adopted in which the circumferential width (circumferential dimension) WF1 of the adjacent barb flap 251N is made longer than the other flap flaps. Furthermore, as shown in FIG. 14(c), a load-bearing reinforcement structure LF can be considered in which the thickness of a connecting portion 251J, which is the boundary between the base of the adjacent barb flap 251N and the ring main body 25A, is made thicker than the other flap flaps. Although the barb flap 251 has been described as an example of applying the load-bearing reinforced structure LF, the same approach can be taken with the lip-shaped barb body 250 that is continuous with the body portion of the end ring 25.

[0050] When the consumer removes the end ring 25 from the bottle body 1, the consumer uses the indicator 3 to align the position for starting removal. For this purpose, a container-side indicator 31 and an end ring-side indicator 32 are provided. On the other hand, existing lid structures (bottle cap structures) are equipped with an indicator to check the optimum tightening state of the bottle cap 2 at the factory level. Therefore, at least the tightening check indicator on the bottle body 1 can be used as one of the indicators for removing the end ring 25 (container-side indicator 31). [Explanation of symbols]

[0051] C container 1 bottle body 2 bottle caps 3. Indicators 4 Operation instructions display 1 bottle body 10 laps 11 Torso 12 Lid closing section 13 Spout 14 Male thread 15 Ring stopper upper flange 16 Ring stopper lower flange 17 Ring holder 18 Ring exit 15 Ring stopper upper flange 151 Guide flange cutout 152 Notched end face 152e Induction Edge 152f induction slope 152t top edge 152tL top line 152c Corner 152r Corner removal section 153 Notched end face 2 bottle caps 21 Cap body 22 Female thread 23 Weakened part 23A Bridge section 25 End Ring 25 End Ring 25A Ring body 250 Barbed 251 Return flap 251J continuous section 251N Adjacent return flap 252 Free end 252L free end line 254 Return flap gap 255 Guidance barb-free part 3. Indicators 31 Container side indicator 32 End ring side indicator 3R recessed type indicator 31R Recessed type container side indicator 32R recessed type end ring side indicator CP Cutproof Shape LF Load-bearing reinforced structure P lead starting point W1 Cutout dimensions W2 Non-return part dimensions Z Effective Guidance Zone W3 Effective induction zone dimension WF Return flap width WF1 Circumferential width (circumferential dimension) WG Gap between return flaps WP Return flap pitch dimension f1 induction start flap f2~fn Subsequent return flaps D Arrow (removal direction) θS Initial deviation setting angle θM Opening margin angle

Claims

1. In a structure in which an end ring attached to a bottle cap attached to a lid closing portion of a bottle body, which is separated from the cap body when the lid is opened and remains in a ring receiving portion of the bottle body, is detached and removed from the bottle body, The ring receiving portion is formed by a recess between the ring stopper upper flange and the ring stopper lower flange, and the ring stopper upper flange is open at the upper side at the guide flange cutout portion, The end ring is provided with a barb along its inner periphery to prevent it from coming off and abut against the ring retaining upper flange to remain in the ring receiving portion, and the circumferential barb is configured to be divided by a guide barb-free portion in a partial range where the barb is not formed, When removing the end ring, the guide barb-free portion and the guide flange cutout portion are placed adjacent to each other to set a fixed removal start point, and the restriction imposed by the ring stopper upper flange on the end ring is partially released, causing the end ring to assume a removal guide tilted posture at the start of its removal. The end ring removal structure for a resin bottle cap is characterized in that the guide flange cutout portion has a pair of cutout end faces on both sides, and the cutout end face that the barb that passes through the guide flange cutout portion abuts during the initial closing of the bottle cap is configured to form a corner removal portion by cutting off the corner.

2. The end ring removal structure for a resin bottle cap described in claim 1, characterized in that the end ring is partially connected to the cap body at multiple points by bridge portions which are components of the weakened portion, but in the portion without the guide barb, the number of bridge formation points is reduced compared to other portions, or the bridge portions are made thinner, or the bridge portions are eliminated altogether.

3. An indicator is formed between the end ring and the bottle body to indicate that a fixed removal start point has been set.

3. The end ring removal structure for a resin bottle cap as described in claim 1 or 2, characterized in that, when the guide flange cutout portion and the guide non-flange portion are adjacent to each other at a fixed removal start point setting, the container side indicator is formed approximately in the center of the effective guide zone dimension, which is the sum of the cutout dimension of the guide flange cutout portion and the non-flange dimension of the guide non-flange portion, and the end ring side indicator is formed shifted from this toward the removal operation direction.

4. 3. The end ring removal structure for a resin bottle cap according to claim 1, wherein the guide flange cutout is formed at the terminal end of a male thread formed on the lid closing portion of the bottle body.

5. 3. The end ring removal structure for a resin bottle cap according to claim 1, wherein the corners of the barb are rounded in a side view, and the cross-sectional shape of the free end of the barb is also rounded at the tip.

6. The end ring removal structure for a resin bottle cap as described in claim 1 or 2, characterized in that the barb body adjacent to the non-provided guide barb portion is provided with a load-bearing reinforcement structure that keeps the end ring, which is pulled upward with a certain force as the cap body is opened, in the ring receiving portion.

7. A container having a bottle body and a bottle cap attached to a lid closing portion of the bottle body as main components, and having a structure for removing and removing an end ring from the bottle body when the lid is opened and remaining in a ring receiving portion of the bottle body, The ring receiving portion is formed by a recess between the ring stopper upper flange and the ring stopper lower flange, and a guide flange cutout portion is formed in a part of the ring stopper upper flange, and the guide flange cutout portion is open at the top, The end ring is provided on its inner circumferential side with a barb for preventing it from coming off, which abuts against the ring stopper upper flange for remaining in the ring receiving portion, and the barb is configured to be divided by a guide barb-free portion in a state where the barb is not formed in a part of the range. When removing the end ring, the guide barb-free portion and the guide flange cutout portion are placed adjacent to each other to set a fixed removal start point, and the restriction imposed by the ring stopper upper flange on the end ring is partially released, causing the end ring to assume a removal guide tilted posture at the start of its removal. The guide flange cutout portion has a pair of cutout end faces on both sides, and a corner removal portion formed by cutting off a corner is formed on the cutout end face that abuts the barb that passes through the guide flange cutout portion when the bottle cap is initially closed.

Images