Opening tab and can lid

Abstract

To accommodate the thinning of the can-opening tab while preventing bending during opening. [Solution] The tab body is provided with a rivet hole portion fixed to the rivet of the can lid body, a nose portion for pushing down the opening piece of the can lid body to open it, and a lifting portion that is pulled up to push down the nose portion, and a curl portion is formed where the peripheral edge is curled to the back side, and the curl portions on both sides of the nose portion have an outer upper curved portion and an outer lower curved portion that are convex radially outward from the top surface portion in a longitudinal cross section along the radial direction of the rivet hole portion, an inner lower curved portion provided radially inward of the outer lower curved portion and bending upward, and an inner upper curved portion provided above the lower curved portion and bending radially outward, and when the radii of curvature of the outer surfaces of the outer lower curved portion, inner lower curved portion and inner upper curved portion are R1b, R2, and R3 respectively, R1b > R2 ≥ R3.

Description

Technical Field

[0001] The present invention relates to an opening tab of a stay-on tab type that is fixed on a can lid body and opens a drinking mouth by pushing down a part of the can lid body while it is attached to the can lid body, and a can lid having such an opening tab attached thereto.

Background Art

[0002] As an opening tab (hereinafter, may be simply referred to as a tab) provided on a can lid of a beverage can, a stay-on tab type that can open a drinking mouth while the tab is attached to the can lid body is known. The can lid provided with this tab has the tab attached by a rivet. By pulling up one end portion (lifting portion) of the tab, the vicinity of the rivet serves as a fulcrum, and the other end portion (nose portion) of the tab serves as a point of action, pressing an opening piece surrounded by a score on the panel surface and immersing the opening piece into the can while breaking the score, thereby opening it. At this time, the start end and the end end of the score are separated, and the opening piece is pushed into the beverage can without leaving the can lid body to open the can.

[0003] As such a tab, for example, those described in Patent Document 1 are known. This tab has a nose portion disposed at the front end of the tab, a lift portion disposed at the rear end of the tab, a rivet hole, a rivet receiving portion disposed in proximity to the nose portion and attached to the nose portion, and a curl portion provided on the outer edge of the tab. The curl portion is formed by bending a region near the outer edge of the tab material into a curl, and has a first surface which is the upper surface, a second surface which is the bottom surface, and an end surface defining the outer edge. The region near the outer edge of the tab material is bent at one or a plurality of thin portions so that the substantially flat portion of the first surface and the substantially flat portion of the second surface come into contact. That is, in the curl portion, the region near the outer edge of the tab material is curved downward and is bent so as to approach more perpendicularly to the substantially flat portion of the second surface as it heads toward a fold portion formed by the deformation of one or a plurality of thin portions.

Prior Art Documents

[0004] [Patent Document 1] Special Publication No. 2009-538803 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] Incidentally, from the perspective of weight reduction, there is a demand to make the tabs thinner. However, when the tabs are made thinner, their rigidity decreases, which causes a problem in that the tabs bend when they are raised to open the can, making it difficult to open. The tab described in Patent Document 1 also has the problem that the folded part collapses and bends when the can is opened.

[0006] This invention has been made in view of these circumstances, and aims to prevent bending during opening while accommodating the thinning of the can-opening tab. [Means for solving the problem]

[0007] The can-opening tab of the present invention comprises a tab body that forms the outer shape, a rivet hole portion that is fixed to the rivet of the can lid body, a nose portion provided at the tip of the tab body for pushing down the opening piece of the can lid body to open it, and a lifting portion provided on the opposite side of the tab body from the rivet hole portion relative to the nose portion for lifting up to push down the nose portion, and a curled portion formed by the peripheral edge being curled to the back side. In a plan view, with the front side facing upwards and the opposite back side facing downwards, and with the nose portion facing forward relative to the center line that passes through the center of the rivet hole and runs along the length of the tab body, the left and right sides are considered as follows: At least a portion of the curled portion to the left of the center line of the nose portion has, in a longitudinal cross-section along the radial direction of the rivet hole portion, a top surface portion, an outward upper curved portion that is obliquely upward and convex radially outward from the top surface portion, an outward lower curved portion provided below the outer peripheral edge of the outward upper curved portion and obliquely downward, an inward lower curved portion provided radially inward of the outward lower curved portion and bending obliquely downward, and an inward upper curved portion provided above the lower curved portion and bending obliquely upward, wherein when the radii of curvature of the outer surfaces of the outward lower curved portion, the inward lower curved portion, and the inward upper curved portion are R1b, R2, and R3 respectively, R1b > R2 ≥ R3.

[0008] This can-opening tab has a curved section on both sides of the nose that includes an outer upper curved section and an outer lower curved section that continue from the top surface, an inner lower curved section that bends upward radially inward from the outer curved section, and an inner upper curved section that bends radially outward above the lower curved section. In particular, the radius of curvature of the inner lower curved section and the inner upper curved section is small, which increases the overall shape rigidity of the curved section and thus prevents deflection during can-opening operations.

[0009] In the tab described in Patent Document 1, as shown in Figure 2, the radius of curvature of the bent portion formed on the lower inner side of the curled portion is larger than the radius of curvature of other parts. Therefore, when the tab is pulled up, this part is prone to crushing and deformation, which may prevent the can from being opened.

[0010] In the can-opening tab of the present invention, it is preferable that a rising wall is provided between the inner lower bent portion and the inner upper bent portion. In this case, it is preferable that the angle of inclination of the rising wall with respect to the thickness direction of the can-opening tab, which is perpendicular to the radial direction of the rivet hole, be between 0° and 30°.

[0011] Because this can-opening tab has a rising wall, its rigidity is further enhanced, making it less prone to bending.

[0012] In the can-opening tab of the present invention, when the distance between the innermost position of the inner lower bend and the outermost position of the outer upper curve or the outer lower curve along the radial direction is W1 mm, and the distance between the innermost position and the tip of the inner upper bend is W2 mm, it is preferable that W2 / W1 be 0.3 or more and 0.6 or less.

[0013] If W2 is too large, the tip is likely to become wavy from the inner upper bend, making it difficult to ensure sufficient rigidity. If W2 is too small, it may come into contact with the top surface of the tab and cause damage.

[0014] The can lid of the present invention comprises a tab and a can lid body, wherein the rivets of the can lid body are fixed to the rivet holes of the tab. [Effects of the Invention]

[0015] According to the present invention, since an inner lower bend and an inner upper bend with a smaller radius of curvature are formed relative to the outer lower curved portion of the tab, the rigidity of the tab is increased in these inner parts, preventing deformation when pulled up during can opening and providing an easy-to-open can lid. [Brief explanation of the drawing]

[0016] [Figure 1] This is a plan view of a can lid having an opening tab according to an embodiment of the present invention. [Figure 2] Figure 1 shows a longitudinal cross-section passing through the center of the rivet on the can lid. [Figure 3] This is a plan view of the tab for opening cans. [Figure 4] Figure 3 shows a longitudinal cross-sectional view along the center line passing through the center of the rivet hole of the can-opening tab. [Figure 5] This is an enlarged cross-sectional view along the radial direction of the rivet holes in the area indicated by A1 of the can-opening tab shown in Figure 3. [Figure 6] This photograph shows the degree of deformation when the can is opened using the opening tab. [Modes for carrying out the invention]

[0017] Hereinafter, embodiments of the can-opening tab and the can lid according to the present invention will be described with reference to the drawings. The can lid 1 of the present embodiment is a so-called stay-on tab type can lid used for cans such as beverage cans. As shown in FIGS. 1 and 2, it is composed of a can lid body 10 and a can-opening tab 20 attached to the can lid body 10. Further, the can lid 1 configured in this way is wound around the opening end of a can body (not shown) filled with contents, thereby manufacturing a can that seals the inside of the can body. These can bodies, can lid bodies 10, and can-opening tabs 20 are each formed of an aluminum alloy.

[0018] The can lid body 10 includes a substantially disk-shaped panel portion 11 and an annular countersink portion 12 provided so as to protrude downward along the outer peripheral portion of the panel portion 11. And a panel boss 13 formed in a concave shape is provided in a part of the panel portion 11. On the surface of this panel boss 13, a score 15 that defines an opening piece 14, a rivet 16 to which the tab 20 is attached, and a finger hook recess 17 disposed on the opposite side of the opening piece 14 via the rivet 16 are provided.

[0019] As shown in FIGS. 3 and 4, the can-opening tab 20 has a curled portion 22 formed by bending the peripheral edge of a tab body 21 that forms an outer shape to the lower surface side, and the overall rigidity is enhanced. And near the center of this tab body 21, a fixing portion 24 having a rivet hole portion 23 fixed to the rivet 16 of the can lid body 10 is provided. The fixing portion 24 is partitioned and formed by a U-shaped slot 25. And the can-opening tab 20 is attached to the can lid body 10 by inserting the rivet 16 of the can lid body 10 into the rivet hole portion 23 formed in the fixing portion 24 and crimping the head of the rivet 16 in a state where the lower surface of the fixing portion 24 abuts against the bottom surface of the panel boss 13.

[0020] Furthermore, the can-opening tab 20 includes a nose portion 26 provided at the tip of the tab body 21 to push down the opening piece 14 of the can lid body 10 to open it, a lifting portion 27 provided at the rear end of the tab body 21, which is positioned on the opposite side of the fixing portion 24 from the nose portion 26 and is pulled up from the can lid body 10 to push down the nose portion 26, and a finger-grip hole portion 28 provided between the lifting portion 27 and the fixing portion 24 of the tab body 21 and penetrating in the thickness direction. Hereinafter, in a plan view of the can-opening tab 20, the front side will be considered upward, and the opposite back side will be considered downward. The front side is the surface that is visible when attached to the can lid body 10 (the surface shown in Figure 1), and the back side is the surface opposite the front side, which is the surface that is in contact with the can lid body 10. Furthermore, the left and right sides are positioned with the nose portion 26 facing forward relative to the center line C (the center line of the tab body 21 that passes through the center of the rivet hole 23 and the tip of the nose portion 26) which runs along the length of the tab body 21 and passes through the center of the rivet hole 23.

[0021] As described above, the peripheral edge of the tab body 21, including the nose portion 26 and the lifting portion 27, is bent downwards to form a curled portion 22. However, in the lifting portion 27, a recess 29 is formed at the rear end of the tab body 21, specifically in a part of the lower surface of the curled portion 22 (the central part in the width direction). Therefore, the thickness of the lifting portion 27 is thinner than the overall thickness of the can-opening tab 20 (the thickness from the upper surface of the lifting portion 27 to the lower surface of the curled portion 22 that protrudes downwards on the tab body 21).

[0022] Furthermore, while the lifting portion 27 has an outer shape perpendicular to the center line C along the length direction of the tab body 21, the outer shape of the nose portion 26 in plan view is formed in the shape of an arc with a radius of curvature Rn centered on the center of the rivet hole portion 23.

[0023] Also, FIG. 5 shows a longitudinal section along the radial direction of the rivet hole portion 23 in a part of the curl portion 22 on the left side of at least the center line C of the nose portion 26 (the range will be described later). As shown in this FIG. 5, the curl portions 22 on both sides of the nose portion 26 include the top surface portion 31 of the tab body 21, an obliquely upward outer upper curved portion 32a that is curved to protrude outward from the top surface portion 31, and an obliquely downward outer lower curved portion 32b provided below the outer peripheral edge of the outer upper curved portion 32a, a lower surface portion 33 that is continuous with the lower edge of the outer lower curved portion 32b and extends radially inward, an inner lower bent portion 34 that is connected to the radially inner edge of the lower surface portion and is bent to protrude obliquely downward and rises upward, a rising wall 35 connected to the upper end of the lower bent portion 34, and an inner upper bent portion 36 that is bent to protrude obliquely upward from the upper end of the rising wall 35.

[0024] The outer upper curved portion 32a and the outer lower curved portion 32b are formed by one arc or a plurality of continuous arcs from the top surface portion 31 to the lower surface portion 33 of the tab body 21. In the example shown in FIG. 5, the radius of curvature R1a of the upper part of the outer curved portion 32 is slightly smaller than the radius of curvature R1b of the lower part, but they may have the same radius of curvature. That is, the relationship is R1a < R1b or R1a = R1b. Also, the lower surface portion 33 following the outer lower curved portion 32b is formed with a certain width up to the inner lower bent portion 34. This lower surface portion 33 is arranged substantially parallel to the top surface portion 31 and is in contact with the surface of the panel boss 13 of the can lid body 10.

[0025] Then, the inner lower bent portion 34 is continuous with the radially inner edge of the lower surface portion 33. In the case of the illustrated example, this inner lower bent portion 34 is bent at an acute angle, and the rising wall 35 is on its upper edge, and the inclination angle θ with respect to the thickness direction of the tab body 21 extends vertically or obliquely upward at 0° or more and 30° or less, and the inner upper bent portion 36 is continuous with its upper edge. This inclination angle θ is preferably 5° or more and 25° or less. In the case of the illustrated example, the inclination angle θ is set to about 20°.

[0026] Furthermore, the inner upper bent portion 36 is bent at approximately 90°, and its tip portion 37 is directed inward towards the curled portion 22. In this case, the tip portion 37 extending from the inner upper bent portion 36 is inclined slightly downward with respect to the horizontal direction perpendicular to the thickness direction. The outer surface of the inner upper bent portion 36 is positioned with a small gap between it and the back surface of the top portion 31 of the tab body 21. This gap may be absent, and the outer surface of the inner upper bent portion 36 may be in contact with the back surface of the top portion 31. Alternatively, the tip portion 37 extending from the inner upper bent portion 36 may be inclined slightly upward with respect to the horizontal direction, in which case the tip portion 37 may be in contact with the back surface of the top portion 31.

[0027] When the radius of curvature of the outer surface of the outer upper curved portion 32a is R1a and the radius of curvature of the outer surface of the outer lower curved portion 32b is R1b, and the radii of curvature of the outer surfaces of the inner lower bend portion 34 and the inner upper bend portion 36 are R2 and R3, respectively, the dimensional relationship is R1a ≤ R1b and R1b > R2 ≥ R3. In other words, the radius of curvature R2 of the inner lower bend portion 34 and the radius of curvature R3 of the inner upper bend portion 36 are smaller than the radius of curvature R1b of the outer lower curved portion 32b. The radius of curvature R2 of the inner lower bend portion 34 and the radius of curvature R3 of the inner upper bend portion 36 may be the same dimension, but the radius of curvature R3 of the inner upper bend portion 36 may be smaller than the radius of curvature R2 of the inner lower bend portion 34. In the illustrated example, R2 > R3.

[0028] To illustrate with specific dimensions, this can-opening tab 20 is formed by processing a metal plate with a thickness of 0.26 mm to 0.30 mm, preferably 0.27 mm to 0.29 mm. The radius of curvature R1b of the outer lower curved portion 32b is 0.8 mm to 1.4 mm, the radius of curvature R2 of the inner lower bend portion 34 is 0.2 mm to 0.5 mm, and the radius of curvature R3 of the inner upper bend portion 36 is 0.3 mm or less. More preferably, R1b is 1.0 mm to 1.3 mm, R2 is 0.3 mm to 0.5 mm, and R3 is 0.2 mm or less.

[0029] Furthermore, the thickness t1 of the curled portion 22 in this area (the distance in the thickness direction of the tab from the upper surface of the top surface portion 31 to the lower surface of the bottom surface portion 33) is 1.2 mm or more and 1.7 mm or less, preferably 1.3 mm or more and 1.6 mm or less. This curled portion 22 is formed on the left side of the nose portion 26 (the area shown as A1 in Figure 3, as will be described later), but it is preferable to set the thickness t1 of the curled portion 22 to different dimensions on the left and right sides of the nose portion 26. For example, it is preferable that t1 be 1.5 mm or more and 1.6 mm or less on the left side of the nose portion 26 (the area shown as A1 in Figure 3), and t1 be 1.3 mm or more and 1.4 mm or less on the right side of the nose portion 26 (the area symmetrical to the area shown as A1 in Figure 3 via the center line C). By making the thickness of the curled portion 26 on the left side of the nose portion 26 greater than on the right side in this way, the score 15 below the tab 20 can be broken sequentially from the starting end, preventing accidental opening.

[0030] The width of the curled portion (the distance W1 from the outermost position of the outer upper curved portion 32a or outer lower curved portion 32b along the radial direction of the rivet hole portion 23 to the innermost position of the inner lower bend portion 34) is 1.5 mm or more and 2.0 mm or less, preferably 1.6 mm or more and 1.9 mm or less. The indentation width of the tip portion 37 (the distance along the radial direction from the innermost position of the inner lower bend portion 34 to the tip of the tip portion 37 along the radial direction of the rivet hole portion 23) W2 is 0.7 mm or more and 1.2 mm or less, preferably 0.8 mm or more and 1.1 mm or less. The distances W1 and W2 have a relationship where W1 / W2 is between 0.3 and 0.6.

[0031] The angle range for both sides of the nose portion 26 that forms the shape of the curled portion 22 is such that the center line passing through the center of the rivet hole 23 along the length of the tab body 21 (the center line of the tab body 21 passing through the center of the rivet hole 23 and the tip of the nose portion 26) is 0°, and the clockwise angle around the center of the rivet hole 23 is 30° to 80°, preferably 40° to 70°. This is the range shown as A1 in Figure 3.

[0032] In addition, in parts other than the nose section 26, the curled section has an outer upper curved section and an outer lower curved section that are almost the same as the nose section 26, but the inner lower bend and inner upper bend are bends that bend from bottom to top with the same radius of curvature as a whole, or even if the dimensions are slightly different there is no part corresponding to a rising wall, or they have an inner lower bend, a rising wall and an inner upper bend, similar to both sides of the nose section, so the shape differs in each part.

[0033] Regarding other dimensions, although not necessarily limited, the length Lt of the can-opening tab 20 along the aforementioned center line C is 24.0 mm or more and 26.0 mm or less, preferably 24.3 mm or more and 25.1 mm or less. Also, the maximum width Wt of the can-opening tab 20 perpendicular to the center line C is 15.0 mm or more and 17.0 mm or less, preferably 15.6 mm or more and 16.4 mm or less. Furthermore, the radius of curvature Rn of the nose portion 26 in plan view is 6.5 mm or more and 8.5 mm or less, preferably 7.0 mm or more and 7.8 mm or less, and may be formed by multiple radii of curvature within that range.

[0034] The can-opening tab 20, constructed in this manner, is formed by sequentially performing processes such as punching holes, cutting out the outer shape, and curling while feeding a strip-shaped sheet material in the length direction, and then separating it from the sheet material. The molded can-opening tab 20 is then attached to the can lid body 10 by passing the rivet 16 of the can lid body 10 through the rivet hole 23 and crimping the rivet 16.

[0035] A beverage can is manufactured by crimping this can lid 1 onto the opening of a can body filled with beverage. In this beverage can, when the lifting portion 27 of the opening tab 20 is pulled up, the nose portion 26 presses against the opening piece 14 with the vicinity of the rivet 16 acting as a fulcrum, and the score 15 first breaks (pops) in the portion between the nose portion 26 and the rivet 16. Then, when the tab 20 is pulled further upward, the break of the score 15 progresses sequentially clockwise (tears) and the broken opening piece 14 is folded inward. By bending the opening piece 14 inward with the tab 20, the score 15 breaks to its end point.

[0036] During this can-opening operation, a force acts on the tab 20 to bend the portion between the nose portion 26 and the rivet 16. Therefore, if the strength of the tab 20 is insufficient, bending may occur at that point, hindering can-opening and potentially resulting in can-opening defects such as being unable to break the score 15 or the breaking of the score 15 stopping midway.

[0037] In this regard, in the tab 20 of this embodiment, the curled portions 22 on both sides of the nose portion 26 have an inner lower bend portion 34, a rising wall 35, and an inner upper bend portion 36 at radially inward positions of the outer upper curved portion 32a and the outer lower curved portion 32b. Since the radii of curvature R2 and R3 of these inner lower bend portion 34 and inner upper bend portion 36 are small and the rising wall 35 extends in the vertical direction, the shape rigidity is increased, and therefore, deflection during the can opening operation is prevented. Therefore, the series of actions of lifting the tab 20 and pushing the opening piece 14 into the can ensure that the score 15 is properly broken from start to finish, preventing can opening failures.

[0038] It should be noted that the present invention is not limited to the configuration of the above-described embodiment, and various modifications can be made to the detailed configuration without departing from the spirit of the present invention. For example, the rising wall is assumed to have an inclination angle θ of 0° or more and 30° or less with respect to the thickness direction of the can-opening tab, which is perpendicular to the radial direction of the rivet hole. In the example shown in Figure 5, it is inclined inward towards the curled portion 22 (radially outward from the rivet hole portion 23), but this also includes the case where it is inclined outward towards the curled portion 22 (radially inward from the rivet hole portion 23). [Examples]

[0039] For the tab material, a 0.280 mm thick sheet of rolled material made from JIS A5182 Al-Mg aluminum alloy was used and formed into tabs. In this case, tabs with the curled shape of this embodiment and tabs with the conventional curled shape were produced as comparative examples. Furthermore, as a standard conventional example, tabs with the conventional curled shape were also produced from a 0.32 mm thick sheet of the same JIS A5182 Al-Mg aluminum alloy. On the other hand, the can lid body was manufactured from a 0.235 mm thick rolled material made of JIS A5182 aluminum alloy, and the three types of tabs mentioned above were attached to it.

[0040] For these samples, the can lid was placed on a can opening load measuring machine, a locking device was attached to the tab's lifting section, and the locking device was pulled at a predetermined speed to investigate whether or not there was any deflection of the tab when it was raised to 90°. Furthermore, with the tab rotated 90° on the can lid body (i.e., the nose portion detached from the opening piece surrounded by the score, preventing the score from breaking), the tab was raised using a can opening load measuring device, and the load until the tab broke was also measured. Ten cans were measured, and the average value was calculated.

[0041] Figure 6 is a photograph showing the deflection state after the tab has been raised to 90°. Due to springback, the angle is smaller than 90°. (a) shows the tab of the conventional example, (b) shows the tab of the comparative example, and (c) shows the tab of this embodiment. In each, the upper row shows the entire tab, and the lower row shows a magnified view of the tip (nose) of the tab.

[0042] As can be seen in Figure 6, the tab in the conventional example appears to have a slight deflection, but this does not cause any practical problems. In the comparative example, a large deflection occurred at the tip of the tab. The tab in the embodiment did not deflect, similar to the conventional example. Furthermore, the load when the tab bent was 32.78 N in the conventional example, 28.53 N in the comparative example, and 31.75 N in the example. These results indicate that the embodiment, while being a lightweight tab with a thinner plate thickness, possesses excellent strength comparable to conventional examples with a thicker plate thickness, and is a tab that does not flex when opening a can. [Explanation of Symbols]

[0043] 1 Can lid 10 Can lid body 11 Panel section 12 Countersink section 13 Panel Debossing 14 Opening piece 15 score 16 rivets 20 Opening tabs 21 Tablet body 22 Curl section 23 Rivet hole 24 Fixing part 25 slots 26 Nose section 27 Lifting section 31 Top section 32a Upper outer curved part 32b Lower outer curved part 33 Bottom part 34. Inner lower curve 35. Rising wall 36. Inner upper curved section 37 Tip

Claims

1. The tab body that forms the outer shape includes a rivet hole portion that is fixed to the rivet of the can lid body, a nose portion provided at the tip of the tab body for pushing down the opening piece of the can lid body to open it, and a lifting portion provided on the opposite side of the tab body from the rivet hole portion that is pulled up to push down the nose portion, and a curled portion is formed where the peripheral edge is curled to the back side. In a plan view, with the front side facing upwards and the opposite back side facing downwards, and with the nose portion facing forward relative to the center line that passes through the center of the rivet hole and runs along the length of the tab body, the left and right sides are considered as follows: A tab for opening cans, wherein a portion of the curled portion of the nose portion, at least to the left of the center line, has, in a longitudinal cross-section along the radial direction of the rivet hole portion, a top surface portion, an outer upper curved portion that is obliquely upward and convex radially outward from the top surface portion, an outer lower curved portion provided below the outer peripheral edge of the outer upper curved portion and obliquely downward, an inner lower curved portion provided radially inward of the outer lower curved portion and bending obliquely downward, and an inner upper curved portion provided above the lower curved portion and bending obliquely upward, wherein when the radii of curvature of the outer surfaces of the outer lower curved portion, the inner lower curved portion, and the inner upper curved portion are R1b, R2, and R3 respectively, R1b > R2 ≥ R3.

2. The can-opening tab according to claim 1, characterized in that a rising wall is provided between the inner lower bend and the inner upper bend.

3. The can-opening tab according to claim 2, characterized in that the angle of inclination of the rising wall with respect to the thickness direction of the can-opening tab, which is perpendicular to the radial direction of the rivet hole, is 0° or more and 30° or less.

4. The can-opening tab according to claim 1, characterized in that, along the radial direction, when the distance between the innermost position of the inner lower bend or the inner upper bend and the outermost position of the outer upper curve or the outer lower curve is W1 mm, and the distance between the innermost position and the tip of the inner upper bend is W2 mm, W2 / W1 is 0.3 or more and 0.6 or less.

5. A can lid comprising a can-opening tab and a can lid body as described in any one of claims 1 to 4, wherein the rivets of the can lid body are fixed to the rivet holes of the tab.

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