JP7133586B2 - can body - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bottle-shaped can having a curled portion at an opening to which a cap is attached.

A bottle-shaped can body (bottle can) made of steel, aluminum alloy, etc., which is filled with contents such as beverages, has a structure in which a cap is attached to the opening of the can body, and a liner on the inner surface of the cap seals the inside. Are known. In such a can body, a curled portion having the same shape as the mouth of the bottle is formed at the opening of the can body, and the skirt portion of the cap is wrapped around the curled portion to seal the inside of the can body. A container is proposed. The can body used for this container has a relatively large curled portion relative to the opening of the can body.

For example, in Patent Document 1, a metallic bead portion (curl portion) formed by curling the tip of the mouth portion outward is wound and fixed with a cap that is opened by tearing the score by pulling a tab. A can is disclosed. In addition, in Patent Document 1, the mouth portion extends straight, and the bead portion (curl portion) formed at the tip of the mouth portion is inclined inward, and the inclination start position is the bead portion. and the curl start position. Further, the curled tip of the bead portion (curl portion) abuts against the outer surface of the mouth portion substantially vertically.

In the metal bottle can disclosed in Patent Document 2, a diameter-reduced portion whose diameter is reduced from the upper end of the mouth portion, a rising portion extending upward from the upper end of the diameter-reduced portion, an upper curved portion at the upper end of the rising portion, and an upper portion thereof A curved portion extending downward while spreading smoothly outward from the curved portion, a lower curved portion at the lower end of the curved portion, and a straight portion linearly extending from the lower curved portion to the diameter-reduced portion. , are formed. The tip of the straight portion is in contact with the outer surface of the reduced diameter portion. Further, the angle of inclination of the reduced diameter portion is 25° to 65°, the radius of curvature of the upper bent portion is 0.5 to 1.0 mm, the radius of curvature of the curved portion is 2.0 to 3.0 mm, and the radius of curvature of the lower bent portion. is 0.5 to 1.0 mm, and the angle of the straight portion with respect to the horizontal is 0° to 25°.

WO2007/122971 JP 2011-116456 A

Such a curled portion has a shape similar to that of the bottle mouth and is relatively large. For this reason, the radius of curvature of the lower end of the curled portion, into which the skirt portion of the cap is wound, tends to become large, and there is a risk that the pressure resistance after the skirt portion of the cap is attached may decrease. On the other hand, if the radius of curvature of the lower end of the curled portion is made small, the sharp tip portion hits the lips of the person trying to drink the beverage in the can, making it difficult to drink.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and provides a can body in which the skirt portion of the cap attached to the curl portion can be reliably wrapped around and fixed, and which causes less discomfort to the lips when drinking. intended to

The can body of the present invention is a can body comprising a cylindrical portion, a neck portion having a diameter smaller than that of the cylindrical portion, and a mouth portion connected to the neck portion. has a curled portion formed by folding and winding radially outward, and the curled portion includes, in a longitudinal section passing through the can axis, an outer peripheral upper bent portion forming an outer peripheral portion of the folded top portion; an outer peripheral side tubular portion extending downward in the can axial direction from the lower end of the outer peripheral upper bent portion; and a curled end portion extending radially inward from the inner peripheral edge of the outer peripheral lower curved portion through an inflection portion while reducing the diameter and including the edge. The radius of curvature of the outer surface of the outer peripheral upper bent portion is R5 (mm), the radius of curvature of the outer surface of the outer peripheral lower bent portion is R6 (mm), and the curvature radius of the outer surface of the inflection portion is R7 (mm). Then, R7<R6<R5, the curled end portion is arranged below the folded top portion in the can axial direction, and the inflection portion is formed by the starting end of the radially outer side of the curled end portion and the lower bent portion of the outer circumference. It is provided with a radius of curvature smaller than that of the curled end portion and the lower curved portion of the outer periphery .

The curvature radius R7 of the outer surface of the inflection portion is preferably 0.03 mm or more and 0.3 mm or less. Moreover, it is preferable that the curvature radius R6 of the outer surface of the outer peripheral lower bent portion is 0.3 mm or more and 0.9 mm or less.

In the outer peripheral portion of the curled portion, an inflection portion with a small radius of curvature is provided between the outer peripheral lower bent portion and the curl end portion, so that when the skirt portion of the cap is wrapped around the curled portion, the inflection portion is formed. The skirt portion of the cap can be locked and fixed securely.

In addition, in this curled portion, since the inflection portion is arranged only in a small portion between the outer peripheral lower curved portion and the curled end portion, there is little sense of incongruity with the lips when drinking.

In this case, the curled end portion is curved in a linear shape or a curved shape that is slightly convex downward in the can axis direction in the longitudinal section passing through the can axis.

The outer surface of the outer peripheral side tubular portion is linear or slightly convex radially outward with a curvature radius larger than the curvature radius R5 of the outer surface of the outer peripheral upper bent portion in the longitudinal section passing through the can axis. It is formed in a curved shape.

As a preferred embodiment of this can body, the edge of the curled end is positioned in the longitudinal section passing through the can axis in a state in which it is in close proximity to the outer surface of the mouth portion starting end located at the mouth portion starting end position. facing or in contact with each other, the starting end portion of the mouth portion is curved so as to be convex outward in the radial direction while gradually decreasing in diameter upward in the axial direction of the can; The radius of curvature of the convex outer surface of the starting end is 6.3 mm or more and 10.3 mm or less.

As a preferred embodiment of this can body, the outer diameter D of the curled portion is 31 mm or more and 35 mm or less, and the thickness of the curled portion in the radial direction is T, the ratio of the outer diameter D to the thickness T (T/D) is 0.06 or more and 0.15 or less.

It is preferable that the thickness T of the curled portion in the radial direction is 2.0 mm or more and 4.5 mm or less.

As a preferred embodiment of this can body, the width W of the curled portion in the can axis direction is 3.0 mm or more and 5.0 mm or less, more preferably 3.5 mm or more and 4.7 mm or less.

According to the present invention, the skirt portion of the cap attached to the curled portion can be reliably rolled up and fixed, and the lips feel little discomfort when drinking.

1 is a front view showing a bottle container using a can body of one embodiment of the present invention, with the right half of the bottle container taken as a cross section passing through the can axis. FIG. 2 is an enlarged cross-sectional view of the vicinity of the curl portion of the can shown in FIG. 1; FIG. 3 is a cross-sectional view further enlarging the vicinity of the lower portion of the curled portion shown in FIG. 2; FIG. 2 is a front view of the bottle container of FIG. 1 seen from different angles; FIG. FIG. 6 is a top view of the bottle container shown in FIG. 5; It is the front view which made the cross section the right half which shows the first half of the manufacturing process of a can in order of (a) and (b). It is the front view which made the right half the cross section which shows the latter half of the manufacturing process of a can in order from (a) to (c). FIG. 4 is a cross-sectional view showing a state of processing with a rolling tool in a curling process; FIG. 4 is a cross-sectional view showing a state of processing with a shaping tool in a curling process; FIG. 10 is an enlarged cross-sectional view of the main part of FIG. 9;

Hereinafter, one embodiment of the can body according to the present invention will be described with reference to the drawings. As shown in FIGS. 1, 4 and 5, the can body 100 of the present embodiment is a bottle can whose entirety is formed in the shape of a bottle. It has curls 50 to form 15 . After the can body 100 is filled with contents such as a beverage through the opening 15 , the opening 15 is sealed by attaching a cap 200 to the mouth 14 to form a bottle container 300 .

1, 4 and 5 show a bottle container 300 comprising a can body 100 and a cap 200 attached to the mouth portion 14 of the can body 100. FIG. 1, the right half of the bottle container 300 is shown as a cross section passing through the can axis C. As shown in FIG.

The can body 100 is made of a thin sheet metal such as aluminum or an aluminum alloy, and as shown in FIG. It is formed in the shape of a cylinder with a bottom including a body portion 10 having a cylindrical shape whose diameter is reduced toward 15 .

As shown in FIG. 1, the body portion 10 and the bottom portion 20 are arranged coaxially with each other. In the direction along the can axis C (the can axis C direction), the direction from the opening 15 to the bottom 20 side is defined as the lower side (downward), and the direction from the bottom 20 to the opening 15 side is defined as the upper side (upper side). , In the following description, the vertical direction is defined in the same manner as the direction shown in FIG. A direction perpendicular to the can axis C is called a radial direction. Of the radial directions, the direction approaching the can axis C is radially inward (inward), and the direction away from the can axis C is radial outward ( outside). The direction of rotation around the can axis C is defined as the circumferential direction.

In this embodiment, the bottom portion 20 of the can body 100 includes a dome portion 21 that is positioned on the can axis C and bulges upward (inside the body portion 10), and the dome portion 21 A heel portion 22 connecting the outer peripheral edge portion and the lower end portion of the trunk portion 10 is provided. The connecting portion between the dome portion 21 and the heel portion 22 is placed on the ground surface (mounting surface) so that the can body 100 is in an upright posture (a posture in which the opening 15 shown in FIG. 1 faces upward). The grounding portion 23 is in contact with the ground surface when the grounding surface is pressed. The ground contact portion 23 protrudes downward most from the bottom portion 20 and has an annular shape extending in the circumferential direction.

As shown in FIG. 1, the barrel portion 10 of the can body 100 includes a cylindrical portion 11 formed in a cylindrical shape on the lower side (bottom portion 20 side) of the barrel portion 10, and a radially inner portion at the upper end of the cylindrical portion 11. an elongated neck 13 connected to the upper end of the shoulder 12 and extending upward in the can axis C direction; and a mouth portion 14 connected to the upper end and opened to the outside. The cylindrical portion 11, the shoulder portion 12, the neck portion 13, and the mouth portion 14 each form an annular shape extending over the entire circumference of the body portion 10 in the circumferential direction.

The neck portion 13 has a shape whose diameter gradually decreases upward in the direction of the can axis C, and is formed to have a smaller diameter than the cylindrical portion 11, with the upper end of the neck portion 13 having the smallest diameter. The height of this neck portion 13 is formed slightly smaller than the height of the cylindrical portion 11 . In the can body 100 of this embodiment, the neck portion 13 is formed into a tapered tubular shape that continues from the upper end of the shoulder portion 12 and gradually decreases in diameter in the can axis C direction. The upper end portion 13a of the neck portion 13 has a small angle with respect to the can axis C and is formed substantially along the direction of the can axis C (see FIG. 2). A mouth portion 14 is connected to the upper end of the upper end portion 13 a of the neck portion 13 .

The mouth portion 14 has a curled portion 50 formed by folding and winding an end portion including the edge E radially outward. More specifically, as shown in FIG. 2, it is continuous with the upper end portion 13a of the shoulder portion 12, gradually decreasing in diameter upward in the can axis C direction, and protruding radially outward. a curved mouth portion starting end portion 41, an inner peripheral lower curved portion 42 extending upward in the direction of the can axis C while curving so as to be convex radially inward from the upper end of the mouth portion starting end portion 41, and an inner periphery an inner peripheral side cylindrical portion 43 that is continuous with the upper end of the lower curved portion 42 and vertically extends upward in the direction of the can axis C at the innermost position of the mouth portion 14; and a curled portion 50 that is folded back radially outward. In a cross section (longitudinal section) passing through the can axis C, the inner cylindrical portion 43 is arranged substantially parallel to the can axis C. As shown in FIG.

The mouth portion starting end portion 41 bulges radially outward, and the radius of curvature R1 (mm) of the convex outer surface is formed to be 6.3 mm or more and 10.3 mm or less. It bulges inward, and its outer surface (convex surface) has a radius of curvature R2 (mm) of 1.0 mm or more and 5.0 mm or less. When the radius of curvature R2 of the inner peripheral lower curved portion 42 is large, the inner peripheral cylindrical portion 43 and the inner peripheral lower curved portion 42, which are continuous with the upper end thereof, can be regarded as substantially integrated, and it is difficult to distinguish between them. Become.

In a cross section (longitudinal section) passing through the can axis C, the curled portion 50 includes an inner peripheral upper bent portion 51 that is bent so as to spread radially outward from the upper end of the inner peripheral cylindrical portion 43, and an inner peripheral upper bent portion. A folded top portion 52 that bends upward in the can axis direction while folding back from the outer peripheral edge of the portion 51, and an outer peripheral upper bent portion 53 that bends downward in the can axis C direction from the outer peripheral edge of the folded top portion 52. an outer peripheral side cylindrical portion 54 extending downward in the can axial direction from the outer peripheral edge of the outer peripheral upper bent portion 53; and a curled end portion 57 extending radially inward from the outer circumference lower bent portion 55 via an inflection portion 56 while decreasing in diameter and having an edge E. formed continuously. A folded top portion 52 arranged between the inner peripheral upper curved portion 51 and the outer peripheral upper curved portion 53 is arranged at the uppermost position in the curl portion 50 .

The curvature radius R3 (mm) of the outer surface (convex surface) of the inner peripheral upper bent portion 51 is 0.8 mm or more and 1.4 mm or less, and the curvature radius R4 (mm) of the outer surface (convex surface) of the folded top portion 52 is 1.0 mm or more. It is 2.5 mm or less, and the curvature radius R5 (mm) of the outer surface (convex surface) of the outer peripheral upper bent portion 53 is 2.0 mm or more and 3.0 mm or less. In some cases, the folded top portion 52 and the outer peripheral upper curved portion 53 are continuously formed with substantially the same radius of curvature.

In this embodiment, as shown in FIG. 3, the outer cylindrical portion 54 is formed so as to slightly increase in diameter downward in the direction of the can axis C, and its inclination is at an angle θ is 0° or more and 1.8° or less. The curvature radius R6 (mm) of the outer surface of the outer peripheral lower bent portion 56 is 0.3 mm or more and 0.9 mm or less.

The inflection portion 56 is provided at a small portion between the lower end of the outer peripheral lower bent portion 55 and the starting end of the curled end portion 57, and the curvature radius R7 (mm) of the outer surface thereof is 0.03 mm or more and 0.03 mm or more. 3 mm or less. Therefore, between the lower end of the outer peripheral lower bent portion 55 and the starting end of the curled end portion 57, the inflection portion 56 is formed linearly along the circumferential direction with a slight width.

Further, as described above, since the outer peripheral cylindrical portion 54 is formed so as to slightly increase in diameter downward in the can axial direction, the starting end portion of the outer peripheral lower bent portion 56 continuing to the lower end of the outer peripheral cylindrical portion 54 is the curled portion. 50 is arranged radially outward.

If the curvature radius R7 of the inflection portion 56 exceeds 0.3 mm, the engagement when the skirt portion of the cap 200 is rolled becomes weak, impairing the sealing performance. If the radius of curvature R7 is less than 0.03 mm, molding defects such as cracking of the inflection portion 56 will occur.

On the outer surface of the curled portion 50, if the radius of curvature R5 of the outer peripheral upper bent portion 53 exceeds 3.0 mm, the sealing performance may deteriorate. may occur. Also, if the radius of curvature R6 of the outer peripheral lower bent portion 55 exceeds 0.9 mm, there is a risk that the skirt portion of the cap 200 will be less likely to be involved. On the other hand, if the radius of curvature R6 is less than 0.3 mm, cracks or wrinkles may occur in the curled portion 50 during the molding process of the curled portion 50 .

The curvature radius R5 of the outer surface of the outer peripheral upper curved portion 53, the outer surface curvature radius R6 of the outer peripheral lower curved portion 56, and the outer surface curvature radius R7 of the inflection portion 55 have a relationship of R7<R6<R5.

The curled end portion 57 is tapered from the inner peripheral edge of the inflection portion 56 while curving slightly so as to protrude linearly or downward in the can axial direction.
Since the opening 41 is curved so as to be convex radially outward as described above, its outer surface forms a convex outer surface. The tip of the curled end portion 57 extends toward the midway position in the direction of the can axis C at the mouth portion starting end portion 41, and as shown in FIG. are opposed to or in contact with the convex outer surface of the mouth start end 41 in close proximity.

As shown in FIG. 2, the width W (mm) of the curled portion 50 in the can axis C direction is parallel to the can axis C from the upper end position of the curled portion 50 to the lower end position of the curled portion 50 in the can axis C direction. vertical distance. In a cross section passing through the can axis C, the folded top portion 52 is arranged at the uppermost position of the curled portion 50 in the can axis C direction, and the tip of the curled end portion 57 is arranged at the lowermost position of the curled portion 50 in the can axis C direction. The width W of the curled portion 50 is the vertical distance from the upper outer surface of the folded top portion 52 to the tip of the curled end portion 57 .

The radial thickness T (mm) of the curled portion 50 is defined as the horizontal distance perpendicular to the can axis C from the innermost position to the outermost position of the curled portion 50 in the radial direction. In the longitudinal section passing through the can axis C shown in FIG. 2, the starting end of the inner peripheral upper bent portion 51, in other words, the position of the upper end of the inner peripheral side cylindrical portion 43 is arranged at the most radially inward position of the curl portion 50, A starting end portion of the outer peripheral lower bent portion 55 is arranged at the most radially outward position of the curled portion 50 . Therefore, the thickness T is the horizontal distance from the outer surface (the inner peripheral surface of the can) of the starting end of the inner peripheral upper curved portion 51 to the outer surface of the starting end of the outer peripheral lower curved portion 56 .

In the present embodiment, when the outer diameter of the curled portion 50 is D (mm) (see FIG. 7C), the ratio (T/D) between the outer diameter D and the thickness T is 0.06 or more and 0.15. The thickness T of the curled portion 50 is formed to be 5% or more and 18% or less of the outer diameter D. Specifically, for example, in the can body 100 in which the outer diameter D of the curled portion 50 is 31 mm or more and 35 mm or less, the thickness T of the curl portion 50 is 2.0 mm or more and 4.5 mm or less, preferably 3.0 mm or more and 4.5 mm or less. 0 mm or less.

When the outer diameter D of the curled portion 50 in the can body 100 is 31 mm or more and 35 mm or less, the width W of the curled portion 50 is 3.0 mm or more and 5.0 mm or less, preferably 3.5 mm or more and 4.7 mm or less. be.

2 and 3, the outer cylindrical portion 54 is formed so as to gradually increase in diameter downward in the can axis C direction, but may be formed parallel to the can axis C direction. . Alternatively, the curved surface gently curves radially outward with a radius of curvature sufficiently larger than the radius of curvature R5 of the outer peripheral upper bent portion 53 while gradually expanding downward in the direction of the can axis C. may be formed. That is, in a vertical cross section passing through the can axis C, the outer peripheral side tubular portion 54 is straight or slightly convex radially outward with a radius of curvature larger than the radius of curvature R5 of the outer surface of the outer peripheral upper bent portion 53. It is formed in a curved shape.

The plate thickness of the can body 100 is not necessarily limited, but the original plate thickness of the aluminum alloy plate before forming is 0.250 mm to 0.500 mm, and the plate thickness at the curl portion 50 is 0.200 mm to 0.200 mm. .600 mm.

In order to manufacture the can body 100 configured in this way, first, as shown in FIG. , the cup 61 is formed into a cylindrical body 62 by drawing and ironing (DI processing). The bottom portion 20 is also molded by this processing.

Next, the diameter of the upper portion of the cylindrical body 62 is reduced by die necking, and the shoulder portion 12 and the neck portion 13 are formed as shown in FIG. 7(a). At this stage, the mouth portion starting end portion 41 is continuously formed on the upper end portion 13 a of the neck portion 13 . The cylindrical portion 63 is formed with the same outer diameter.

Next, as shown in FIGS. 7(b) and 8, the cylindrical portion 63 is folded radially outward at its end including the edge E and wound, thereby forming the inner circumferential side cylindrical portion 43. Curling is applied to the part above the part that becomes. In this curling process, first, the end portion including the edge E of the cylindrical portion 63 is folded while being expanded by two types of rolling tools 71 and 72, and the roll portion 65 that is rolled continuously to the inner peripheral side cylindrical portion 43 is rolled. to form

The rolling tools 71 and 72 are rotatable around the axes C1 and C2, and have shaping grooves 71a and 72a along their circumferential direction. The cylindrical portion 63 is processed by 71a and 72a. Further, a core 73 is inserted inside the tubular portion 63 to support the tubular portion 63 from the inside.

The rolled portion 65 formed by this processing has an outer shape slightly larger than the curled portion 50 in the final shape, and the edge E of the rolled portion 65 is not in contact with the outer surface of the inner cylindrical portion 43 at this stage.

Next, the shaping tool 74 is brought close to the roll portion 65 while drawing a circular arc as indicated by the white arrow in FIG. This shaping tool 74 is also rotatable about an axis (not shown) and has shaping grooves 74a along its circumferential direction. 65 is processed. Also at this time, the core 75 is arranged inside the roll portion 65 to support the roll portion 65 from the inside.

By processing with this shaping tool 74, as shown in FIG. , an outer peripheral upper curved portion 53, an outer peripheral cylindrical portion 54, an outer peripheral lower curved portion 55, an inflection portion 56, and a curled end portion 57 including an edge E are formed.

In this case, the orthopedic tool 74 pushes the outer surface side of the roll portion 65 obliquely upward, so that the inflection portion 56 having a small curvature radius R7 is formed between the outer peripheral lower bent portion 55 and the curl end portion 57. is formed.

As a result, the curled portion 50 is formed such that the edge E of the curled end portion 57 faces or contacts the outer surface of the opening start portion 41 in close proximity.

As shown in FIGS. 1, 4, and 5, the can body 100 configured in this way is fitted with a cap 200 on the opening 15 of the mouth portion 14 to form a bottle container 300. As shown in FIGS. Specifically, after filling the inside of the can body 100 with the content, the mouth portion 14 is covered with the cap 200 . Then, the cap 200 is pressed downward in the can axis C direction from above to compress the sealing material 205 attached to the inner surface of the cap 200, and the lower end of the skirt portion (cylindrical portion) of the cap 200 is pressed. The skirt portion is deformed so as to follow the outer surface of the curl portion 50 by pressing radially inward with the claws of the tool. As a result, the lower end of the skirt portion is caught on the lower end of the curled portion 50 and the cap 200 is attached to the can body 100 .

In this embodiment, as shown in FIGS. 4 and 5, the cap 200 is made of a thin sheet metal of aluminum or an aluminum alloy, and has a disk-shaped top surface portion 201 and vertically downward from the outer peripheral edge of the top surface portion 201. It has an extending skirt portion, a tab 203 projecting so as to extend a part of the lower edge of the skirt portion in the plane direction, and a sealing member 205 formed from the inner surface of the top surface portion 21 to the inner surface of the upper end portion of the skirt portion. ing. A pair of scores 206 are formed on the outer surfaces of the top surface portion 201 and the skirt portion from both side edges of the tab 203 at the lower edge of the skirt portion to the skirt portion and the top surface portion 201 .

In this attached state of the cap 200, the skirt portion of the cap 200 is wound from the lower end portion of the outer cylindrical portion 54 to the starting end portion of the curled end portion 57 (near the connection portion with the inflection portion 56). Since the curved portion 56 having a small curvature radius R7 is provided at the portion where the skirt portion of the cap 200 is wound, the skirt portion of the cap 200 is engaged with the curved portion 56 and separated from the curl portion 50. is prevented.

In addition, since this inflection portion 56 is arranged only in a small portion between the outer circumference lower side flection portion 55 curved with a relatively large radius of curvature R6 and the curl end portion 57, the lips feel uncomfortable when drinking. less.

The present invention is not limited to the configurations of the above-described embodiments, and various modifications can be made to the detailed configurations without departing from the gist of the present invention.

For example, in the above embodiment, a bottomed cylindrical can body in which the bottom portion 20 and the body portion 10 are integrally formed has been described, but the can body does not necessarily have a bottom portion, and the curled portion is included. It also includes those in which a separately formed bottom is wound around the body after molding.

To provide a can body in which the skirt part of a cap attached to a curl part can be reliably rolled up and fixed, and the lips are less uncomfortable when drinking.

10 Body portion 11 Cylindrical portion 12 Shoulder portion 13 Neck portion 13a Upper end portion 14 Mouth portion 15 Opening portion 20 Bottom portion 21 Dome portion 22 Heel portion 23 Ground portion 41 Mouth start end portion 42 Inner circumference lower curved portion 43 Inner circumference cylinder portion 50 Curl portion 51 Inner circumference upper bent portion 52 Folded top portion 53 Outer circumference upper bend portion 54 Outer circumference side cylindrical portion 55 Outer circumference lower bend portion 56 Inflection portion 57 Curled end portion 100 Can body 200 Cap 201 Top surface portion 300 Bottle container C Can shaft E edge

Claims (8)

A can body comprising a cylindrical portion, a neck portion having a smaller diameter than the cylindrical portion, and a mouth portion connected to the neck portion,
a curled portion formed by folding and winding an end portion including an edge portion radially outward on the outer peripheral portion of the mouth portion;
The curled portion includes, in a longitudinal section passing through the can axis, an outer peripheral upper curved portion forming an outer peripheral portion of the turn-up top portion, an outer peripheral side cylindrical portion extending downward in the can axial direction from the lower end of the outer peripheral upper curved portion, and the outer periphery. An outer peripheral lower bent portion that bends radially inward from the lower end of the side cylindrical portion and projects obliquely downward in the can axial direction, and an inflection portion from the inner peripheral edge of the outer peripheral lower bent portion. extending inward in the radial direction through the curled end portion including the edge, and formed continuously with the curled end portion including the edge,
Let R5 (mm) be the radius of curvature of the outer surface of the outer peripheral upper curved portion, R6 (mm) be the radius of curvature of the outer surface of the lower outer peripheral curved portion, and R7 (mm) be the radius of curvature of the outer surface of the inflection portion, R7<R6<R5,
The curled end portion is disposed below the folded top portion in the can axial direction, and the inflection portion is disposed between the radially outer starting end of the curled end portion and the lower end of the outer peripheral lower curved portion. A can body having a radius of curvature that is smaller than the radius of curvature of the curved portion and the lower curved portion of the outer periphery . 2. The can body according to claim 1, wherein the curvature radius R7 of the outer surface of the inflection portion is 0.03 mm or more and 0.3 mm or less. 3. The can body according to claim 1, wherein the curvature radius R6 of the outer surface of the outer peripheral lower bent portion is 0.3 mm or more and 0.9 mm or less. The outer surface of the outer peripheral side tubular portion is linear or slightly convex radially outward with a curvature radius larger than the curvature radius R5 of the outer surface of the outer peripheral upper bent portion in the longitudinal section passing through the can axis. 4. The can body according to any one of claims 1 to 3, which is formed in a curved shape. The edge of the curled end is in contact with the outer surface of the mouth portion starting end located at the mouth portion starting end position in the longitudinal section passing through the can axis,
The mouth portion starting end is curved so as to be convex radially outward while gradually decreasing in diameter upward in the can axial direction, and has a convex outer surface. 5. The can body according to any one of claims 1 to 4, wherein the radius of curvature of is 6.3 mm or more and 10.3 mm or less. 6. The curled end portion according to any one of claims 1 to 5, characterized in that, in the longitudinal section passing through the can axis, the curled end portion is curved in a straight line or in a curved shape slightly convex downward in the can axis direction. or the can body described in item 1. The outer diameter D of the curled portion is 31 mm or more and 35 mm or less, and the ratio (T/D) between the outer diameter D and the thickness T of the curled portion in the radial direction is 0.06 or more. 7. The can body according to any one of claims 1 to 6, which is 0.15 or less. The can body according to any one of claims 1 to 7, wherein the width W of the curled portion in the can axial direction is 3.0 mm or more and 5.0 mm or less.

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