Screw cap and cap unit

Abstract

To provide a screw cap and a cap unit capable of forming a tamper evident band without applying an excessive load to a bridge when mounted on a vessel mouth part while suppressing an increase in 2nd opening torque when initially opening the cap.SOLUTION: A screw cap according to an aspect of the present invention includes a cap main body including a cap top surface and a skirt wall axially descending from the cap top surface and having a cap-side thread portion formed on an inner peripheral surface thereof, and a TE band connected to a lower portion of the cap main body via a breakable bridge, wherein the TE band has a locking portion including a recessed portion formed on an outer peripheral surface thereof and an inward protruding portion formed so as to protrude toward the inner peripheral surface corresponding to the recessed portion, A plurality of locking parts are intermittently formed along the circumferential direction so that the height of the top part in the axial direction of the recessed part is different.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a technology for sealing the mouth of a container (also referred to as "container mouth"), and more particularly to a screw cap made of synthetic resin and a cap unit including this screw cap and a container mouth. [Background technology]

[0002] Screw caps that can be opened and closed are widely used as beverage containers for water, tea, soft drinks, etc., on bottle containers such as PET bottles and paper cartons with spouts. The opening of these containers is provided with a threaded portion on the container, which is screwed onto the threaded portion on the container to open and close the opening.

[0003] Among such screw caps, caps with tamper-evident features that provide evidence of opening are also in practical use. For example, Patent Document 1 discloses a resin container lid in which the skirt wall is divided into a main portion above the circumferential weakening line and a tamper-evident band below, and the inner peripheral surface of this tamper-evident band is provided with a locking means that locks onto a locking protrusion (also called a "turnip") provided below the male thread on the container opening. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-239184 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the technologies including those described in the above patent documents still cannot be said to meet market needs, and at least the following problems exist: The locking means of the resin cap shown in Patent Document 1 is shown to be multiple locking protrusions formed by deforming part of the tamper-evident band inward.

[0006] During initial opening, the multiple locking protrusions engage with the locking projection (hook) on the container opening, breaking the bridge between the cap body and the tamper-evident band and separating them. If the multiple locking protrusions engage with the hook at almost the same time, there is a concern that the second opening torque (torque to break the bridge) during initial opening will increase, adversely affecting the openability of the cap. On the other hand, if the bridge is weakened so that it breaks easily, there is a risk that the bridge will break unintentionally during a stage prior to initial opening, such as when attaching the cap to the container opening.

[0007] The present invention solves the above-mentioned problems by providing a screw cap and cap unit that can form a tamper-evident band without placing excessive load on the bridge when attached to the container mouth, while suppressing an increase in the second opening torque during initial opening. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, a screw cap in one form of the present invention includes (1) a cap body having a cap top surface and a skirt wall that descends axially from the cap top surface and has a cap-side thread portion formed on its inner surface, and a TE band connected to the lower part of the cap body via a breakable bridge, wherein the TE band has a locking portion consisting of a recess formed on the outer surface and an inward protrusion formed to protrude toward the inner surface side in correspondence with the recess, and the locking portion is formed intermittently in multiple portions along the circumferential direction so that the heights of the tops of the recesses in the axial direction are different.

[0009] Furthermore, in the screw cap described in (1) above, (2) it is preferable that the top of the engaging portion is formed in an arc shape that is convex upward, and that the engaging portion is formed so as to widen in the circumferential direction of the TE band from the upper end to the lower end along the axial direction.

[0010] Furthermore, in the screw cap described in (2) above, (3) it is preferable that the bridge has a plurality of bridging portions arranged intermittently along the circumferential direction, and that the positions of the bridging portions and the tops of the recesses overlap in the circumferential direction.

[0011] Furthermore, in the screw cap described in any of (1) to (3) above, (4) it is preferable that the plurality of locking portions include a first locking portion having a first height from the bottom surface of the TE band to the top, a second locking portion having a second height from the bottom surface to the top that is lower than the first height, and a third locking portion having a third height from the bottom surface to the top that is lower than the second height.

[0012] In order to solve the above-mentioned problems, a cap unit according to one aspect of the present invention is (5) a cap unit including the screw cap described above and a container opening having a container-side threaded portion that can be threaded with the cap-side threaded portion of the screw cap, wherein the container opening is provided with a cover that protrudes radially outward below the container-side threaded portion, and the plurality of engagement portions are intermittently arranged along the circumferential direction on the underside of the cover so that, when threaded, the distance between the top and the underside of the cover in the axial direction varies. [Effects of the Invention]

[0013] In the screw cap and cap unit of the present invention, the recesses in the multiple locking portions are formed so that the heights of the peaks in the axial direction are different, which prevents the bridges formed intermittently along the circumferential direction from breaking all at once during initial opening, thereby preventing an increase in the second opening torque during initial opening. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic diagram showing a half cross section of a cap unit including a screw cap and a container opening according to an embodiment. FIG. [Figure 2] FIG. 2 is a development view of the TE band and bridge portion of the cap unit in FIG. 1. [Figure 3] 3 is a schematic diagram showing a half cross section of the shape of a container opening of a cap unit according to an embodiment. FIG. [Figure 4] 10 is a schematic diagram for explaining a cap attachment step in the fastening portion forming method for forming the fastening portion of the TE band. FIG. [Figure 5] 10 is a schematic diagram showing a state in which a cap is attached to a container opening in a fastening portion forming method for forming a fastening portion of a TE band. FIG. [Figure 6] 10 is a schematic diagram for explaining a locking portion forming step in a locking portion forming method for forming a locking portion of a TE band. FIG. [Figure 7] 10 is a schematic diagram showing an embodiment in which a plurality of types of locking portions (first to third locking portions) having different top heights in the axial direction of the recess are formed in the locking portion forming step. FIG. [Figure 8] 10 is a schematic diagram showing an example of how the bridge breaks when the cap unit according to the embodiment is initially opened. FIG. [Figure 9] FIG. 10 is a development view of a TE band and a bridge portion according to Modification 1. [Figure 10] FIG. 10 is a development view of a TE band and a bridge portion according to Modification 2. DETAILED DESCRIPTION OF THE INVENTION

[0015] The following describes preferred embodiments of the present invention. For the sake of convenience, the X, Y, and Z directions are defined as appropriate in the following description, but it goes without saying that this does not restrict the scope of the present invention. In addition, matters other than the features of the present invention described in detail below can be manufactured by appropriately referring to, for example, the configuration of the cap unit disclosed in Patent Document 1 or the structures of other known screw caps.

[0016] [Cap Unit] FIG. 1 shows a cap unit 300 according to this embodiment. The cap unit 300 of this embodiment is composed of a screw cap 100 having a cap side thread portion 13 and a cylindrical container mouth portion 200 having a container side thread portion 220 that can be screwed into this cap side thread portion 13. The container opening 200, which will be described in detail later, is a portion equipped with a spout through which liquid or solid contents such as food, drink, medicine, etc. are poured out of a container. The container opening 200 may be integral with the container body in which the contents are held, or may be separate from the container body.

[0017] Such a container body may be a resin bottle such as a PET bottle, a paper pack, or a resin pouch, as long as the container opening 200 of this embodiment is applicable. An example of an application of the container opening 200 integral with the container body is the opening of a bottle container such as a PET bottle. An example of the container opening 200 separate from the container body is a spout heat-sealed to a pouch or a paper container.

[0018] <Screw Cap 100> 1 and 2, the screw cap 100 of this embodiment is attached to the container opening 200 of the container described above, and is configured to include a cap body 10 and a TE band 20 connected to the lower part of the cap body 10 via a bridge 30. Examples of resins that can be used to configure the screw cap 100 include known synthetic resins such as low-density PE (polyethylene), high-density PE, PP (polypropylene), and a mixed resin of PE and PP.

[0019] As shown in the figure, the cap body 10 includes a cap top surface 11 and a skirt wall 12 that descends axially (Z direction in the figure) from the cap top surface 11 and has a cap-side thread portion 13 formed on its inner peripheral surface. The cap body 10 may further include a known inner ring 14 extending downward from the lower surface of the cap top surface 11 and a known outer ring 15 provided on the outer peripheral side of the inner ring 14 on the lower surface of the cap top surface 11. Also, as shown in the figure, a known nail 16 extending vertically along the axial direction may be formed over the entire circumference in the circumferential direction on the outer peripheral surface of the skirt wall 12.

[0020] The TE band 20 has a tubular band structure that is annular along the circumferential direction (θz), and is connected to the lower part of the above-described cap body 10 via a breakable bridge 30. The bridge 30 of the present embodiment can be a known bridge structure including a plurality of bridging portions 31 provided intermittently along the circumferential direction (θz direction around the Z axis) as shown in FIGS. 1 and 2. In forming the bridge 30, a method of post-forming the TE band 20 using a tool such as a cutter after forming the screw cap 100 and a method using a mold in which the bridge 30 is formed simultaneously with the molding of the screw cap 100 are common, but the bridge 30 may be formed by any known molding method.

[0021] <Locking portion structure in the TE band> While referring to FIGS. 1 and 2, the locking portion structure in the TE band 20 of the present embodiment will be described. As can be understood from these figures, the TE band 20 of the present embodiment has a locking portion 23 including a recess 21 formed on the outer peripheral surface 20a and an inward protruding portion 22 formed to protrude toward the inner peripheral surface side corresponding to the recess 21.

[0022] As shown in these figures, the locking portion 23 of this embodiment is preferably formed so that the apex TP is formed in an upwardly convex arc shape and is flared from the upper end to the lower end along the axial direction in the circumferential direction of the TE band 20. By using the locking portion 23 in this form, it can be easily formed by pressing the tip end portion Ta of the press-deformable member T, as will be described later.

[0023] 2 and other figures, in the screw cap 100 of this embodiment, it is preferable that the bridging portion 31 constituting the bridge 30 and the apex TP of the recess 21 in the locking portion 23 are positioned so as to overlap in the circumferential direction (i.e., in the example of FIG. 2, the bridging portion 31 is positioned almost directly above the apex TP). This positions the locking portion 23 directly below the bridging portion 31 during initial opening, so that the torque generated during opening is efficiently used to break the bridge 30.

[0024] The recess 21 of the TE band 20 is formed so as to bulge toward the inner periphery by pressing the tip end portion Ta of the press-deformable member T from the outer periphery side of the TE band 20. Therefore, the recess 21 when the TE band 20 is viewed from the outer periphery side corresponds to the inward protrusion 22 when the TE band 20 is viewed from the inner periphery side. In other words, the recess 21 and the inward protrusion 22 are provided on the front and back sides of the TE band 20 as one body.

[0025] In this embodiment, it is preferable that a plurality of locking portions 23 are formed intermittently along the circumferential direction so that the heights h of the peaks TP in the axial direction of the recess 21 are different. More specifically, as shown in Fig. 2, the locking portion 23 may be configured to include a first locking portion 23A (large recess 21A) having a first height h1 from the bottom surface BS of the TE band 20 to the peak TP1, a second locking portion 23B (middle recess 21B) having a second height h2 from the bottom surface BS to the peak TP2, and a third locking portion 23C (small recess 21C) having a third height h3 from the bottom surface BS to the peak TP3. In this case, the third height h3 is set lower than the second height h2, and the second height h2 is set lower than the first height h1. In this embodiment, three different types of locking portions 23 are provided, but as long as they can be formed on the TE band 20, the types of locking portions 23 are not limited to the above-mentioned three types (first locking portion 23A to third locking portion 23C) and may be any number of types, such as two types, four types, or more.

[0026] 2, in the TE band 20 of this embodiment, the first locking portion 23A, the second locking portion 23B, and the third locking portion 23C may be arranged in this order along the circumferential direction. As an example, in this embodiment, the first locking portion 23A, the second locking portion 23B, the third locking portion 23C, the second locking portion 23B, and the first locking portion 23A may be considered as one unit, and multiple locking portions 23 may be provided so that this unit is repeated in the circumferential direction of the TE band 20. As a result, the position of the apex TP is periodically repeated in the TE band 20 so as to describe a sine curve, making it possible to cause the breakage of the bridging portion 31 to occur in a dispersed manner in the circumferential direction during initial opening.

[0027] 2, the circumferential width W1 of the first locking portion 23A (large recess 21A) may be set to be approximately equal to the circumferential width W2 of the second locking portion 23B (middle recess 21B). Furthermore, the circumferential width W1 of the first locking portion 23A (large recess 21A) may be set to be approximately equal to the circumferential width W3 of the third locking portion 23C (small recess 21C). Note that this is just an example, and the widths W of the first locking portion 23A (large recess 21A) to the third locking portion 23C (small recess 21C) may be set appropriately depending on the predetermined unplugging torque and the configuration of the bridging portions 31 (such as the number and circumferential pitch).

[0028] 2, the axial height h3 of the third locking portion 23C (small recess 21C) may be approximately 45 to 55% of the axial height H of the TE band 20. In this embodiment, the axial height h1 of the first locking portion 23A (large recess 21A) may be approximately 65 to 75% of the axial height H of the TE band 20, for example. Furthermore, the axial height h2 of the second locking portion 23B (middle recess 21B) may be approximately 55 to 65% of the axial height H of the TE band 20, for example.

[0029] In this way, in the TE band 20 of this embodiment, a plurality of recesses 21 constituting the locking portion 23 are formed intermittently along the circumferential direction so that the heights h of the tops TP in the axial direction are different. Therefore, as will be described later, the inward protrusions 22 formed integrally with the recesses 21 are spaced apart from the underside 230a of the cap 230 at different distances during initial sealing (when the bridge 30 has not yet broken and the cap is unopened).

[0030] <Container opening 200> Next, the detailed structure of the container mouth 200 in this embodiment will be described with reference to Figure 3 etc. The container mouth 200 in this embodiment may be, for example, a spout made of synthetic resin formed separately from the container body. The container mouth 200 may also be the mouth of a known bottle such as a PET bottle.

[0031] 3, the container mouth 200 of this embodiment is configured to include a cylindrical pouring portion 210, a known container-side thread portion 220 formed on the outer peripheral surface of the cylindrical pouring portion 210, and a known screw thread 220 arranged below the cylindrical pouring portion 210. As shown in the figure, the container mouth 200 of this embodiment may also include a known flange arranged further below the lower surface 230a of the screw thread 230.

[0032] 1 and 3, the cap 230 is a protrusion (locking ring) that protrudes radially outward from the lower side of the container-side threaded portion 220. As a result, when the screw cap 100 is turned in the opening direction, for example, during initial opening, the cap body 10 rises, and the inward protrusion 22 of the TE band 20 locks (gets caught) on the underside 230a of the cap 230, breaking the bridge 30 (bridging portion 31). After the bridge 30 breaks and the cap body 10 is released from the container opening 200, the TE band 20 remains below the cap 230 on the container opening 200, thereby realizing the tamper-evident feature described above (see FIG. 8, etc. as appropriate).

[0033] <Method of forming the locking part (initial sealing process)> 4 to 7, a method for forming the locking portion 23 of the TE band 20 in this embodiment will be described. Note that in this embodiment, as an example, the locking portion 23 of the screw cap 100 will be described as being formed after the screw cap 100 is attached to the container opening 200.

[0034] The method for forming the engaging portion according to this embodiment includes the following cap mounting step and engaging portion forming step. A. Cap attachment process As shown in Figure 4, first, the screw cap 100 is placed above the container opening 200 of a container filled with the contents, and then the screw cap 100 is rotated while being pressed against the container opening 200. At this time, as shown in the figure, the locking portion 23 is not formed on the band precursor 20PR. As a result of the above-mentioned rotation, the cap-side threaded portion 13 and the container-side threaded portion 220 thread together, and the screw cap 100 gradually descends toward the container while rotating.

[0035] As described above, the locking portion 23 has not yet been formed on the band precursor 20PR, and therefore the band precursor 20PR can pass smoothly without interfering with the turnip 230. As the screwing of the screw cap 100 and the container opening 200 continues, the descent of the screw cap 100 stops at a position where the tip of the container opening 200 is sandwiched between the inner ring 14 and the outer ring 15, as shown in FIG.

[0036] According to this embodiment, the diameter of the band precursor 20PR is prevented from being expanded by the cap 230 when the cap is attached to the container, and for example, unintentional breaking of the bridge 30 when the cap is attached is avoided.

[0037] B. Locking part formation process Next, a description will be given of a mode of forming the locking portions 23 on the band precursor 20PR with reference to Figures 6 and 7. In the locking portion forming step, a plurality of types of locking portions (first locking portion 23A to third locking portion 23C) having different heights of the tops TP in the axial direction of the recesses 21 of the TE band 20 described above are formed by the following procedure, for example.

[0038] That is, after the screw cap 100 stops descending through the cap mounting process described above, the locking portions 23 are formed on the outer peripheral surface of the band precursor 20PR via a press-deformable member T as shown in Fig. 6. As shown in the figure, such a press-deformable member T can be exemplified by a cylindrical jig having tip portions Ta intermittently provided along the circumferential direction on its inner peripheral surface.

[0039] More specifically, in the locking portion forming step, the screw cap 100 is rotated along the inner peripheral surface of the press-deformable member T while pressing the outer peripheral surface of the band precursor 20PR while the press-deformable member T is heated. As the screw cap 100 rotates along the inner peripheral surface of the press-deformable member T, recesses 21 are continuously formed on the outer peripheral surface of the band precursor 20PR, and the TE band 20 of this embodiment is formed.

[0040] Each tip portion Ta corresponds to the recess 21 described above, and as can be seen from the drawing, the upper end is formed in an arc shape that convex upward. As described above, the TE band 20 of this embodiment has three types of locking portions 23 (first locking portion 23A, second locking portion 23B, and third locking portion 23C) that are different in size, and therefore, as shown in FIG. 6(b), the tip portion Ta also has three sizes (Ta1, Ta2, and Ta3) that correspond to the three recesses (large recess 21A, medium recess 21B, and small recess 21C).

[0041] When the press-deformable member T has finished forming the recesses 21 and is released from the TE band 20, the locking portions 23 are cooled and fixed in shape while maintaining the shape they had when pressed by the press-deformable member T. As a result, the multiple locking portions 23 provided on the TE band 20 are each positioned below the lower surface 230a of the cap 230.

[0042] 7, when the forming of the recess 21 by the press-deformable member T is completed, the arrangement of the inward protrusion 22 relative to the tab 230 differs for each locking portion 23. In other words, the inward protrusion 22 constituting the first locking portion 23A is close to the tab 230, while the inward protrusion 22 constituting the second locking portion 23B and the third locking portion 23C is spaced apart from the tab 230 (farther away from the tab 230 than the inward protrusion 22 of the first locking portion 23A).

[0043] That is, when the screw cap 100 and the container opening 200 are screwed together, the plurality of locking portions 23 are arranged intermittently along the circumferential direction on the underside of the cap 230 so that the distance between the top portion TP and the underside 230a of the cap 230 in the axial direction varies. This prevents the inward protrusions 22 from interfering with the underside 230a of the cap 230 almost simultaneously during initial opening, thereby preventing a large increase in the second opening torque.

[0044] 7, the locking portion 23 has an apex TP formed in an upwardly convex arc shape and is formed so as to widen in the circumferential direction from the upper end to the lower end along the axial direction, which makes it easy to retract the press-deformable member T downward after forming the locking portion 23, thereby improving work efficiency. The method of forming the locking portion 23 is not limited to the above-described form using the pressure-deformable member T, but may be, for example, a form in which the recess 21 is individually formed on the outer peripheral surface of the TE band 20 using a member having a tip portion Ta.

[0045] <Initial opening> Next, with reference to FIG. 8, a procedure for opening a container equipped with the screw cap 100 of this embodiment will be described. First, the user grips the knurl 16 and rotates the screw cap 100 in the opening direction. Then, the cap body 10 rises as the screw cap 100 rotates, but the TE band 20 is restricted from rising because the engaging portion 23 (inward protruding portion 22) interferes with the lower portion 230a of the cap 230.

[0046] More specifically, in this embodiment, as the cap body 10 rises during initial opening, the apex TP of the first locking portion 23A interferes with the underside 230a of the cap 230, causing stress to concentrate on the bridge 30 (bridging portion 31) of the locking portion 23 that is located above the first locking portion 23A, and causing the bridging portion 31 to begin to break. Then, as the cap body 10 continues to rise, the apex TP of the second locking portion 23B then interferes with the underside 230a of the cap 230, causing stress to be applied to the bridge 30 (bridging portion 31) of the locking portion 23 that is located above the second locking portion 23B, causing the bridging portion 31 to begin to break.

[0047] As the cap body 10 continues to rise, the top TP of the third engagement portion 23C then interferes with the lower surface 230a of the cap 230, causing stress to be applied to the bridge 30 (bridging portion 31) of the engagement portion 23 that is located above the third engagement portion 23C, and the bridging portion 31 also begins to break. As the screw cap 100 rises, all of the bridging portions 31 are broken one after another, leaving the TE band 20 at the container opening 200 while the cap body 10 separates from the container opening 200, completing the initial opening.

[0048] In this embodiment, multiple types of locking portions 23 with different heights of the top TP in the axial direction of the recess 21 are provided on the TE band 20, and when initially opened, the locking portions 23 interfere with the underside 230a of the cap 230 in order of the height of the top TP (i.e., in order of proximity to the cap 230 among the multiple locking portions 23), and the bridging portions 31 located above the locking portions 23 that interfere with the cap 230 are broken sequentially.

[0049] In other words, in the screw cap 100 of this embodiment, by making the shape of the engagement portion 23 (recess 21 and inward protrusion 22) uneven in the circumferential direction as described above, the bridges 30 can be broken sequentially with a relatively small force, allowing for initial opening, compared to a configuration in which all bridging portions 31 break almost simultaneously during initial opening.

[0050] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

[0051] <Variation 1> FIG. 9 shows the TE band structure of a screw cap 100 according to the first modification. In the above-described embodiment, the multiple recesses 21 (inner protrusions 22) that make up the locking portion 23 are provided at approximately equal intervals along the circumferential direction on the TE band 20. However, the present invention is not limited to this aspect, and the multiple recesses 21 (inner protrusions 22) may be provided on the TE band 20 at different intervals along the circumferential direction.

[0052] For example, as shown in FIG. 9, the first gap L1 between the first locking portion 23A and the second locking portion 23B in the circumferential direction may be set larger than the second gap L2 between the second locking portion 23B and the third locking portion 23C in the circumferential direction. In this modified example, "L1>L2" is set, but from the viewpoint of fracture control of the bridge 30, "L1 <L2」であってもよい。

[0053] <Variation 2> FIG. 10 shows the TE band structure of a screw cap 100 according to the second modification. In the above-described embodiment, the widths of the plurality of recesses 21 (inward protrusions 22) constituting the locking portion 23 are set to be substantially uniform. However, the present invention is not limited to this embodiment, and the widths W of the plurality of recesses 21 (inward protrusions 22) may be different from one another.

[0054] 10, for example, the circumferential width W1 of the first locking portion 23A may be set smaller than the circumferential width W2 of the second locking portion 23B. Similarly, the circumferential width W3 of the third locking portion 23C may be set larger than the circumferential width W1 of the first locking portion 23A and the circumferential width W2 of the second locking portion 23B. In addition, in this modified example, the widths W of the first locking portion 23A to the third locking portion 23C are different from each other, but for example, the first locking portion 23A and the second locking portion 23B may have the same width, and only the third locking portion 23C may have a different width.

[0055] <Other variations> In the above-described embodiment, the locking portion 23 is formed to the lower part of the TE band (the lower end in the axial direction), but it does not have to be formed to the lower part of the TE band (the lower end in the axial direction) as long as it can interfere with the cap 230 during initial opening. Furthermore, the locking portion 23 is formed in an upwardly convex arc shape and expands in diameter in the circumferential direction of the TE band as it extends downward, but it may also be formed in other shapes (for example, a recess that is spherical (crater) shaped near the center of the TE band).

[0056] Furthermore, in the above-described embodiment, an example was described in which the container mouth portion 200 is equipped with a cover 230, but the interference form of the engagement portion 23 with the container mouth portion 200 is not limited to this, and for example, the cover 230 may be omitted and the function of the cover 230 may be substituted by the lower end of the container side screw portion 220. Furthermore, in the above-described embodiment, the cap side thread portion 13 and the container side thread portion 220 were formed with an intermittent gap, but for example, at least one of the cap side thread portion 13 and the container side thread portion 220 may have a continuous structure without the above-described gap. [Industrial Applicability]

[0057] As described above, the cap unit including the screw cap and container mouth of the present invention is suitable for realizing a cap structure that suppresses an increase in opening torque during initial opening. [Explanation of symbols]

[0058] 100 screw caps 10 Cap body 20 TE band 30 Bridge 200 Container opening 210 Pour cylinder part 220 Container side screw part 230 Turnip 300 cap units

Claims

1. a cap body including a cap top surface and a skirt wall extending axially downward from the cap top surface and having a cap-side thread portion formed on an inner peripheral surface thereof; a TE band connected to the lower part of the cap body via a breakable bridge, The TE band has a locking portion including a recess formed on an outer peripheral surface and an inward protruding portion formed on an inner peripheral surface side in correspondence with the recess, The locking portions are formed intermittently along the circumferential direction so that the heights of the tops of the recesses in the axial direction are different. A screw cap characterized by:

2. The locking portion is 2. The screw cap according to claim 1, wherein the top portion is formed in an upwardly convex arc shape and is formed so as to widen in the circumferential direction of the TE band from the upper end to the lower end along the axial direction.

3. The bridge includes a plurality of bridging portions provided intermittently along a circumferential direction, The screw cap according to claim 2 , wherein the bridge portion and the top of the recess are positioned to overlap in the circumferential direction.

4. The plurality of locking portions are a first engaging portion having a first height from a bottom surface of the TE band to the top; a second engaging portion having a second height from the bottom surface to the top surface that is lower than the first height; The screw cap according to any one of claims 1 to 3, further comprising: a third engaging portion having a third height from the bottom surface to the top surface that is lower than the second height.

5. A cap unit comprising the screw cap according to claim 1 and a container opening provided with a container-side thread portion that can be threadedly engaged with the cap-side thread portion of the screw cap, a cap that protrudes radially outwardly below the container-side threaded portion is provided at the container opening, The plurality of locking portions are arranged intermittently along the circumferential direction on the underside of the turnip so that the distance between the top and the underside of the turnip in the axial direction varies when the turnip is screwed together. A cap unit characterized by:

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