JP2006176135A - Bag body and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bag body capable of attractively packaging an article such as an object with its outer peripheral shape formed in an approximately curved surface, and a manufacturing method thereof. <P>SOLUTION: The bag body 1 is formed of a tubular film, and has an opening part 10 opened at one end, a bottom part 20 closed at the other end, and a side portion 30 extending from one end to the other end and closed. The outline of an end rim of the bottom part 20 has at least two protruding edges 21 protruding toward the other end of the bag body 1. The bottom part 20 has a portion 40 folded like bellows. The folded portion 40 has at least two inward folds 50 protruding toward the former end inside the bag body1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention generally relates to a bag body and a method for manufacturing the same, and specifically relates to a bag body in which a three-dimensional shape is formed at the bottom during use and a method for manufacturing the same.

  2. Description of the Related Art Conventionally, square-bottom bags suitable for packaging a cube or a rectangular parallelepiped product with a good appearance are known.

For example, Japanese Patent Application Laid-Open No. 2003-137305 (Patent Document 1) proposes a square bottom bag having a configuration that can be manufactured at a higher speed by a simple process.
JP 2003-137305 A

  However, this type of square-bottom bag is suitable for improving the appearance of a cube or a rectangular parallelepiped product, etc., but the product such as a sphere or an object having a substantially curved outer shape is packaged in a good appearance. Not suitable for. For example, when a product such as a spherical ball or watermelon is stored in this type of square bottom bag, an excess space is formed around the product in the inner region of the bottom of the bag. For this reason, the appearance of the product packaged in this type of square bottom bag is deteriorated. As a result, there is a problem that the appearance is deteriorated when the product is displayed at a store. In addition, there is a problem that the state of the product is poor and the packaging state of the product becomes unstable.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a bag body and a method for manufacturing the same, which can package products such as a sphere and an object whose outer peripheral shape is substantially curved.

  A bag according to the present invention is formed of a tubular film, and has an opening opened at one end, a bottom closed at the other end, and a side extending from one end to the other end and closed. The outer shape of the edge of the bottom portion has at least two projecting edges that protrude toward the other end of the bag body, and the bottom portion has a portion folded in a bellows shape, The folded portion has at least two folded portions protruding toward one end inside the bag body.

  In the bag body of the present invention, at least two folded portions protruding toward one end inside the bag body are expanded outward by widening the portion folded in a bellows shape. By forming the folded-back portion spread outward and the end edge of the bottom portion, the substantially curved bottom surface is formed so as to extend along the extending direction. On the other hand, the outer shape of the bottom edge has at least two projecting edges, so that it is formed so as to extend along the direction intersecting the direction in which the substantially curved bottom surface is widened. Therefore, in the bag of the present invention, a substantially spherical bottom surface can be formed by widening the bottom. Thereby, when a product such as a sphere, an object whose outer peripheral shape is formed in a substantially curved shape is put in the bag of the present invention, an excess space around the product is not formed in the inner region of the bottom of the bag, The product can be stored so that the film of the bag body is in close contact with the outer peripheral surface of the product, and the product can be packaged with good appearance.

  In the bag of this invention, it is preferable that the edge of the at least 2 folding | turning part located inside a bag is a linear end edge piled up in alignment with each other.

  In this case, the appearance of the bag body in the folded state before use and the expanded state after use can be improved.

  Moreover, in the bag body of this invention, it is preferable that the folded portion has at least three folded portions that protrude toward the other end outside the bag body.

  In this case, at least two folded portions protruding toward the one end on the inner side of the bag body are expanded outward by expanding the portion folded in a bellows shape, and at the same time, the expanded at least two folded portions However, it is formed so as to extend along the direction in which the substantially curved bottom surface is widened by connecting to at least three folded portions that protrude toward the other end outside the bag body. Thereby, by extending the bottom part of the bag body, a bottom surface having a shape closer to a curved surface can be formed along the direction in which the bag body is expanded.

  Further, in the bag body of the present invention, the end edges of the at least three folded portions located outside the bag body have at least two protruding end edges protruding toward the other end of the bag body, and Preferably they are aligned and stacked.

  In this case, it is possible not only to improve the appearance of the folded bag body before use, but also to provide at least two projecting edges from which the edges of the at least three folded portions located outside the bag body protrude. Therefore, the substantially curved bottom surface is formed so as to extend along the direction intersecting the direction in which the bag body is expanded. Thereby, by extending the bottom portion of the bag body, a bottom surface having a shape closer to a curved surface can be formed even in a direction intersecting with the direction in which the bag body is expanded.

  In the bag of the present invention, it is preferable that the projecting end edge includes a corner formed by intersecting at least two side end edges constituting the outer shape of the bottom end edge.

  In the bag according to the present invention, it is preferable that the projecting end edge includes a curved end edge connecting at least two side end edges constituting the bottom end edge. In this case, by expanding the bottom portion of the bag body, a bottom surface having a shape closer to a curved surface can be formed along the direction intersecting the direction in which the bag body is expanded.

  The manufacturing method of the bag according to the present invention includes the following steps.

  (A) A step of folding the belt-like film so that the cross section has a substantially U shape, and transporting the belt-like film having the bent portion on one side in the longitudinal direction.

  (B) A step of forming at least two folded portions protruding toward the other side portion on the inner side of the belt-like film in the folded portion, and folding one side portion in a bellows shape.

  (C) A step of forming an edge of the bottom portion of the bag body having at least two protruding end edges protruding at a portion folded in a bellows shape by fusing and welding one side portion.

  (D) After forming the edge of the bottom of the bag, it is connected to the edge of the bottom of the bag by fusing and welding so as to cross from one side of the belt-like film toward the other side. Forming a side edge of the bag.

  In the manufacturing method of the present invention, the step of folding one side portion into a bellows is inserted into each of the guide members in which a plurality of grooves are formed at intervals in the vertical direction and the plurality of grooves of the guide members. Using a rotating member in which a plurality of discs are spaced apart in the axial direction, one side of the strip film is passed between each of the plurality of grooves and the discs. preferable.

  In this case, the bottom part of the bag body folded in a bellows shape can be easily formed by using the guide member and the rotating member in combination.

  As described above, by using the bag of the present invention, it is possible to package products such as a sphere and an object whose outer peripheral shape is formed in a substantially curved shape with good appearance.

  An embodiment of the present invention will be described below with reference to the drawings.

  1 is a front view showing a state before use of a bag according to one embodiment of the present invention, FIG. 2 is a sectional view taken along a line II-II in FIG. 1, and FIG. FIG. 4 is a perspective view of the bag shown in FIG. 1 as viewed obliquely from above. 2, 3, and 4 are exaggerated with the bottom of the bag body slightly expanded.

  As shown in FIG. 1, the bag 1 is formed of a tubular film and is closed by extending from one end to the other end, an opening 10 opened at one end, a bottom 20 closed at the other end, and the other end. Side 30. The opening 10 of the bag 1 is formed from an opening edge 11, and the side 30 is formed from two closed side edges 31 and 32.

  The material of the film is generally a synthetic resin, such as polypropylene (PP) or polyethylene (PE). The film is preferably transparent or translucent. The thickness of the film is preferably in the range of 15 to 100 μm, and more preferably in the range of 20 to 80 μm.

  As shown in FIG. 1, the outer shape of the edge of the bottom portion 20 has two protruding end edges 21 that protrude toward the other end of the bag body 1, that is, the bottom portion 20. Each of the protruding edges 21 includes a side edge 22 that forms the outer shape of the bottommost edge, and a side edge that obliquely extends from both sides of the side edge 22 to form both side edges of the bottom. 23 is an angle formed by crossing 23.

  Moreover, as shown in FIG. 1, the bottom part 20 has the part (folded part) 40 folded up in the shape of a bellows. As shown in FIG. 2, the folded portion 40 has four expansion / contraction portions 41, 42, 43, and 44 as a portion that can be expanded or a portion that can be contracted. The four expansion / contraction portions 41, 42, 43, and 44 can be expanded in a substantially fan shape around the expansion / contraction center 70.

  Further, as shown in FIG. 1, the folded portion 40 of the bottom portion 20 is formed with three inner folded portions 50 that protrude toward one end inside the bag body 1. Specifically, as shown in FIG. 2, the three inner folded portions 50 have folded end edges 51, 52, and 53, respectively. As shown in FIGS. 2 and 3, the folded end edges 51, 52, and 53 located inside the bag body 1 are aligned and overlapped with each other. Further, as shown in FIGS. 1 and 4, the folded end edges 51, 52, and 53 each form a linear end edge 24.

  As shown in FIG. 1, four outer folded portions 60 are formed on the outer edge of the folded portion 40 of the bottom portion 20. Specifically, as shown in FIG. 2, the four outer folded portions 60 have folded end edges 61, 62, 63 and 64, respectively. As shown in FIG. 4, each of the folded end edges 61, 62, 63 and 64 has two protruding end edges 21 that protrude toward the other end of the bag body 1, that is, the bottom portion 20. Each of the protruding edges 21 includes a side edge 22 that forms the outer shape of the bottommost edge, and a side edge that obliquely extends from both sides of the side edge 22 to form both side edges of the bottom. 23 is an angle formed by crossing 23. Further, as shown in FIGS. 2 and 4, the folded end edges 61, 62, 63 and 64 located outside the bag body 1 are aligned and overlapped with each other.

  FIG. 5 is a perspective view of the form of the bag shown in FIG. 1 when used obliquely from below.

  As shown in FIG. 5, when the folded end edges 61, 62, 63, and 64 located outside are centered on the expansion / contraction center 70 in the bottom portion 20 of the bag body 1 in a substantially fan shape, the folded end located on the inside Edges 51, 52 and 53 are also spread outward. When widened in this way, a substantially curved bottom surface is formed to extend along the widened direction. Also, in the direction intersecting with the spread direction, the side edge 22 located at the lowest part, the side edge 23 extending obliquely from both sides thereof, and the side edges 22 and 23 intersect. The projecting end edge 21 formed in this way forms the end edge of the bottom portion 20 in a trapezoidal shape or a polygonal shape, so that a substantially curved bottom surface is formed.

  That is, in the bag body 1 of the present invention, by expanding the portion 40 folded in a bellows shape, the three inner folded portions 50 that protrude toward one end inside the bag body 1 are expanded outward. By connecting the inner folded portion 50 widened outward and the side edge 22 and the side edge 23 which are the edges of the bottom portion 20, the substantially curved bottom surface is extended along the direction in which it is widened. It is formed. On the other hand, the outer shape of the edge of the bottom portion 20 has two protruding end edges 21 and is formed so as to extend along the direction intersecting the direction in which the substantially curved bottom surface is widened. Therefore, in the bag body 1 of the present invention, a substantially spherical bottom surface can be formed by widening the bottom portion 20. As a result, when a product such as a sphere or an object whose outer peripheral shape is substantially curved is placed in the bag body 1 of the present invention, an excess space is formed around the product in the inner region of the bottom of the bag body 1. Therefore, the product can be stored so that the film of the bag body 1 is almost in close contact with the outer peripheral surface of the product, and the product can be packaged with good appearance.

  In the above bag 1, three inner folded portions 50 are formed. However, at least two or more inner folded portions 50 may be formed. Preferably, the number of the inner folded portions 50 is two or more and four or less. It is. By increasing the number of the inner folded portions 50, a bottom surface having a shape closer to a curved surface can be formed along the direction in which the bottom portion 20 is expanded.

  In the bag body 1 of the present invention, the folded-back edges 51, 52 and 53 of the three inner folded portions 50 located inside the bag body 1 are linear edges that are aligned and overlapped with each other. The appearance of the bag body 1 in the folded state before use and in the spread state after use can be improved.

  In the bag body 1 described above, the folded end edges 51, 52, and 53 of the three inner folded portions 50 are aligned, but it is not always necessary to align them.

  Further, in the bag body 1 of the present invention, the folded portion 40 has four outer folded portions 60 that protrude toward the other end outside the bag body 1, so the portion 40 folded in a bellows shape. Is expanded, the three inner folded portions 50 projecting toward one end on the inner side of the bag body 1 are spread outward, and at the same time, the three inner folded portions 50 are spread on the outer side of the bag body 1. By connecting to the four outer folded portions 60 projecting toward the other end, the substantially curved bottom surface is formed so as to extend along the extending direction. Thereby, by expanding the bottom portion 20 of the bag body 1, a bottom surface having a shape closer to a curved surface can be formed along the direction in which the bag body 1 is expanded.

  In the bag body 1 described above, the four outer folded portions 60 are formed. However, at least three or more outer folded portions 60 may be formed. Preferably, the number of the outer folded portions 60 is three or more and five or less. . By increasing the number of outer folded portions 60, a bottom surface having a shape closer to a curved surface can be formed along the direction in which the bottom portion 20 is widened.

  Further, in the bag body 1 of the present invention, the folded end edges 61, 62, 63 and 64 of the four outer folded portions 60 located outside the bag body 1 are projected toward the other end of the bag body 1. Since the two end edges 21 are overlapped and aligned with each other, it is possible not only to improve the appearance of the folded bag 1 before use, but also the outer side of the bag 1. Since the two folded end edges 61, 62, 63, and 64 located at 2 have two protruding end edges 21, the substantially curved bottom surface extends along a direction intersecting with the direction in which the bag body 1 is spread. Formed. Thereby, by extending the bottom portion of the bag body 1, a bottom surface having a shape closer to a curved surface can be formed even in a direction intersecting with the direction in which the bag body 1 is expanded.

  In the bag body 1 described above, the two protruding end edges 21 are formed on the outer shape of the end edge of the bottom portion 20, but three or more protruding end edges may be formed. By increasing the number of protruding end edges 21, a bottom surface having a shape closer to a curved surface can be formed. Moreover, in the said bag 1, although the folding | turning edge edges 61, 62, 63, and 64 of the four outer folding | returning parts 60 are aligned, it is not necessary to align.

  In the bag body 1 of the present invention, the protruding edge 21 includes a corner formed by the intersection of the two side edges 22 and 23 constituting the outer shape of the edge of the bottom portion 20. In order to round off, a curved edge may be formed to connect the two side edges 22 and 23. In this case, by expanding the bottom portion 20 of the bag body 1, a bottom surface having a shape closer to a curved surface can be formed along the direction intersecting the direction in which the bag body 1 is expanded.

  FIG. 6 is a perspective view showing a state in which a spherical product is packaged in the bag shown in FIG.

  As shown in FIG. 6, when a packaged object 2 such as tomato, cabbage, watermelon, mandarin orange, daidai, or the like, or a packaged item 2 such as a spherical ball is placed in the bag 1, the rounded bottom of the packaged item 2 is placed. It can be packaged to fit almost exactly. For this reason, since an extra space is not formed between the bag body 1 and the article 2 to be packaged, not only can the fit be good and the package can be stably packaged, but also the product can be packaged with a good appearance. Moreover, if the bag 1 is composed of a transparent or translucent film, the entire surface of the packaged item 2 can be easily seen, and it can be packaged more effectively and in a good-looking manner so that almost the entire outer peripheral surface of the product can be seen. The appearance when products are displayed can be made better.

  In addition, when sports balls such as basketball, volleyball, soccer balls, etc. are packaged in a bag, they could not be printed on the surface of a net-like bag that has been used conventionally. When a spherical ball is packaged using this bag body, it is possible to print on the surface of the bag body to describe product information for advertisement.

  Furthermore, what is packaged using the bag of the present invention is not limited to a sphere, and may be, for example, a half sphere such as a watermelon cut in half or a quarter, and forms a curved surface as a whole. An object having at least an outer peripheral surface can be packaged with good appearance.

  FIG. 7 is a perspective view showing a state in which the bag body shown in FIG. 1 is wrapped with a product having a curved outer peripheral surface and arranged with the bottom portion of the bag body facing upward.

  As shown in FIG. 7, vegetables such as broccoli are placed in a transparent bag 1 as an example of the article to be packaged 2 and are arranged so that the bottom of the bag 1 faces upward. When the products are arranged and displayed in this way, the outer surface with the characteristic of broccoli as an example of the article to be packaged 2 can be emphasized. Even when a product with a curved surface such as a helmet is displayed as the article to be packaged 2, if the bottom portion of the bag body 1 is brought into close contact with the curved surface and the bottom portion faces upward, A certain outer surface can be highlighted.

  The opening 10 of the bag 1 of the present invention may be configured such that the opening edge 11 is folded back and closed with an adhesive tape, or may be closed by wrapping a string or the like. Further, a hanging hole for display, a long hole for hand-down, and the like may be formed in the vicinity of the opening 10.

  Next, an example of the manufacturing method of the bag 1 will be described as one embodiment of the present invention.

  FIG. 8 is a plan view (A) and a side sectional view (B) conceptually showing one embodiment of the manufacturing process of the bag shown in FIG.

  As shown in FIG. 8A, the belt-like film 100 is conveyed in the longitudinal direction continuously in the direction indicated by the arrow P in a state where the cross section of one side portion is bent so as to have a substantially U shape. Thereafter, three folded portions protruding toward the other side portion on the inner side of the belt-like film 100 are formed in the folded portion, and one side portion is folded in a bellows shape. Specifically, one folded side portion of the belt-like film 100 is inserted between the guide member 200 and the rotating member 300 to form a folded portion.

  FIG. 9 is a perspective view showing a state in which one side portion of the belt-like film is bent in FIG.

  As shown in FIG. 9, in the folded portion 110 of the belt-like film 100, inner folded portions 111, 112, and 113 and outer folded portions 114, 115, 116, and 117 are formed.

  FIG. 10 shows a cross section viewed from the direction along line XX in FIG. 8, and a side cross-sectional view (A) showing a state where the guide member 200 and the rotating member 300 are spaced apart from each other. It is a sectional side view (B) which shows the state arrange | positioned with the rotation member 300 approaching.

  As shown in FIG. 10A, the guide member 200 is supported by a support column 210 and is provided so as to be movable in the direction indicated by the arrow U. In the guide member 200, three guide grooves 220, 230 and 240 are formed at intervals in the vertical direction. The rotating member 300 includes discs 320, 330, and 340 that are rotatable around a shaft 310, and is provided so as to be movable in a direction indicated by an arrow V. The discs 320, 330, and 340 are disposed so as to be insertable into the guide grooves 220, 230, and 240, respectively.

  The substantially U-shaped bent portion 110 of the belt-like film 100 is passed between the guide member 200 and the rotating member 300, and the guide member 200 and the rotating member 300 are moved in a direction approaching each other. Then, as shown in FIG. 10B, the disks 320, 330, and 340 are inserted into the guide grooves 220, 230, and 240, respectively, and the bent portion 110 is not shown in the figure. 9 and 340 and each of the guide grooves 220, 230 and 240, it is folded into a bellows shape as shown in FIG. In this way, the inner folded portions 111, 112, and 113 and the outer folded portions 114, 115, 116, and 117 are formed in the folded portion 110 of the belt-like film 100. At this time, the disks 320, 330, and 340 of the rotating member 300 rotate in the direction in which the strip film 100 is conveyed, that is, in the direction indicated by the arrow T in FIG.

  In addition, by increasing the number of guide grooves of the guide member 200 and the number of disks of the rotating member 300, the number of folded portions can be increased in the portion folded in a bellows shape. In addition, the length of the folded portion can be adjusted by adjusting the distance between the guide member 200 and the rotating member 300.

  Next, as shown in FIG. 8B, when the belt-like film 100 is pressed by the pinch roller 600, the folded portion 110 has the inner folded portions 111, 112, and 113 and the outer folded portions 114, 115, 116, and 117 are folded so that they are in close contact with each other.

  After that, as shown in FIG. 8B, one side of the belt-like film 100 is brought into contact with a part of the folded portion 110 of the belt-like film 100 by pressing the fusing and welding heating plate 400 in the direction indicated by the arrow Q. The flanks of the fusing are welded. As a result, as shown in FIG. 8A, one side portion of the belt-like film 100 is fused in a substantially triangular shape to form the protruding end edge 21 and the side edge edges 22 and 23 in the bent portion 110. To do. In this way, the edge of the closed bottom of the bag is formed.

  And after conveying the strip | belt-shaped film 100 with the feed roller 700, as shown to (B) of FIG. 8, in the state which received the strip | belt-shaped film 100 with the base roller 800, the heating blade 500 which melts and welds to the front-end part of the strip | belt-shaped film 100. Are brought into contact with each other and pressed in the direction indicated by the arrow R, thereby fusing and welding so as to cross from one side of the strip-shaped film 100 toward the other side. As a result, as shown in FIG. 8A, the side edges 31 and 32 are formed as the edges of the closed side portion of the bag body by being cut off from the belt-like film 100, and the opened opening edge. 11 and a closed side edge 23 connected to the side edges 31 and 32, a protruding edge 21 and a side edge 22 are completed. The completed bag is conveyed in the direction indicated by the arrow S in FIG.

  The embodiment disclosed above should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above embodiments but by the scope of claims, and includes all modifications and variations within the meaning and scope equivalent to the scope of claims.

It is a front view which shows the state before use of the bag body according to one embodiment of this invention. It is sectional drawing seen from the direction along the II-II line of FIG. It is sectional drawing seen from the direction along the III-III line of FIG. It is the perspective view which looked at the bag body shown by FIG. 1 from diagonally upward. It is the perspective view which looked at the form at the time of use of the bag shown by FIG. 1 from diagonally downward. It is a perspective view which shows the state which packaged the spherical product in the bag shown by FIG. It is a perspective view which shows the state which packaged the goods with an outer peripheral surface curved surface by the bag body shown by FIG. 1, and has arrange | positioned it with the bottom part of the bag body facing up. It is the top view (A) and side sectional view (B) which show notionally one embodiment of the manufacturing process of the bag body shown by FIG. It is a perspective view which shows the state by which one side part of the strip | belt-shaped film was bent in FIG. FIG. 8 is a cross-sectional view taken along line XX in FIG. 8, and a side cross-sectional view (A) showing a state in which the guide member 200 and the rotating member 300 are arranged with a space therebetween, and the guide member 200 and the rotating member 300. It is a sectional side view (B) which shows the state arrange | positioned closely.

Explanation of symbols

  1: bag body, 10: opening, 20: bottom, 21: protruding edge, 22, 23: side edge, 24: linear edge, 40: folded portion, 50: inner folded portion, 51, 52, 53, 61, 62, 63, 64: folded edge, 60: outer folded portion, 100: strip-shaped film, 110: folded portion, 111, 112, 113: inner folded portion, 114, 115, 116, 117: outer folded portion, 200: guide member, 220, 230, 240: guide groove, 300: rotating member, 320, 330, 340: disc.

Claims (8)

A bag formed of a tubular film and having an opening opened at one end, a bottom closed at the other end, and a side extending from one end to the other end and closed,
The outer shape of the edge of the bottom part has at least two protruding edges protruding toward the other end of the bag body, and the bottom part has a portion folded in a bellows shape. The portion has at least two folded portions protruding toward one end inside the bag body.   The bag according to claim 1, wherein edges of at least two of the folded portions located inside the bag are linear edges that are aligned and overlapped with each other.   The bag according to claim 1 or 2, wherein the folded portion has at least three folded portions protruding toward the other end outside the bag.   The edges of the at least three folded-back portions located outside the bag body have at least two protruding edge edges protruding toward the other end of the bag body, and are overlapped with each other. The bag according to claim 3.   5. The protrusion according to claim 1, wherein the protruding edge includes a corner formed by intersecting at least two side edges that form an outer shape of the bottom edge. 6. The described bag.   The bag according to any one of claims 1 to 5, wherein the protruding edge includes a curved edge that connects at least two side edges constituting the edge of the bottom portion. Folding the belt-like film so that the cross-section has a substantially U-shape, and conveying the belt-like film having this bent portion on one side in the longitudinal direction;
Forming at least two folded portions protruding toward the other side on the inner side of the belt-like film in the folded portion, and folding one side in a bellows shape; and
Forming one edge of the bottom of the bag having at least two protruding edges protruding at the portion folded in a bellows shape by fusing and welding one side;
After forming the bottom edge of the bag body, the bag connected to the bottom edge of the bag body by fusing welding so as to cross from one side of the belt-like film toward the other side Forming a side edge of the body. The step of folding the one side portion into a bellows shape includes a guide member in which a plurality of grooves are formed at intervals in the vertical direction, and a plurality of disks inserted into each of the plurality of grooves of the guide member. It is performed by passing one side part of a strip-like film between each of a plurality of above-mentioned grooves and the above-mentioned disk using a rotation member arranged at intervals in the direction of an axis. The manufacturing method of the bag body as described.

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