Paper bags and their manufacturing method

Abstract

To provide a paper bag capable of preventing an outer patch from entering the inside of a cylindrical part as a foreign matter after the opening of the cylindrical part is opened.SOLUTION: The paper bag includes: a cylindrical bag body having a cylindrical part and an opening part; and an outer patch. The opening part has lower paper and upper paper, the lower paper has a lower paper base and a lower paper folding part, the upper paper has an upper paper base and an upper paper folding part, an inner surface of the lower folding part is pasted to the lower paper base and the upper paper base via an opening glue 117, the inner surface of the upper paper folding part is pasted to the outer surfaces of the upper paper base, the lower paper base and the lower paper folding part via an opening glue 118 and an opening glue 119, the outer patch is attached to the outer surfaces of the upper paper base, the lower paper base and the lower paper folding part via an opening glue 120 and an opening glue 121, and is attached to the outer surface of the upper paper folding part via a fixing glue 122, and the outer patch is attached to a part of an exposure part 127 of the lower paper and upper paper base via a spot fixing glue 139.SELECTED DRAWING: Figure 16

Description

[Technical field]

[0001] The present disclosure relates to paper bags and methods for making the same. [Background technology]

[0002] Conventionally, a paper bag is known that includes a tubular bag body having a tubular portion and a tear-opening portion formed integrally with the tubular portion, and an outer patch provided on the tear-opening portion. An opening is formed in the tubular portion, and the tear-opening portion opens and closes when the tear-opening portion deforms. With the tear-opening portion closing the opening of the tubular portion, the outer patch is attached to the tear-opening portion via tear-opening glue. By attaching the outer patch to the tear-opening portion, deformation of the tear-opening portion that would open the opening of the tubular portion is suppressed (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-107689 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration described in Patent Document 1, when an operator deforms the tearing portion to open the opening of the tubular portion, the outer patch is peeled off from the tearing portion, which causes a problem that the outer patch peeled off from the tearing portion may enter the inside of the tubular portion as a foreign object.

[0005] The present disclosure has been made to solve the problems described above, and its purpose is to provide a paper bag and a manufacturing method thereof that can prevent the outer patch from entering the inside of the tubular portion as a foreign object after the opening of the tubular portion is opened. [Means for solving the problem]

[0006] The paper bag according to the present disclosure comprises a tubular bag body having a tubular portion and an opening portion for opening and closing the opening of the tubular portion, and an outer patch provided in the opening portion, the opening portion having a bottom paper and a top paper which are integrally provided on the tubular portion and overlap each other to close the opening, the bottom paper having a bottom paper base and a bottom paper fold portion provided on the bottom paper base, the top paper having an top paper base and an top paper fold portion provided on the top paper base, the inner surface of the bottom paper fold portion is bonded to the bottom paper base and the top paper base via opening glue, and the inner surface of the top paper fold portion is bonded to the outer surfaces of the top paper base, the bottom paper base and the bottom paper fold portion via opening glue. The outer patch is attached to the outer surfaces of the upper paper base, lower paper base and lower paper fold using opening glue and to the outer surface of the upper paper fold using adhesive glue, the boundary line between the lower paper base and the lower paper fold is the lower paper fold, the boundary line between the upper paper base and the upper paper fold is the upper paper fold, the portion between the lower paper fold and the upper paper fold in the lower paper base and upper paper base that is not overlapped by either the lower paper fold or the upper paper fold is the exposed portion of the lower paper upper paper base, and the outer patch is attached to a portion of the exposed portion of the lower paper upper paper base using spot adhesive glue. In the paper bag according to the present disclosure, the end of the outer patch in the width direction of the paper bag is attached to the portion where the spot adhesive glue is applied in the exposed portion of the upper base of the lower paper. In the paper bag of the present disclosure, the portion of the outer surface of the lower folded portion where the upper folded portion is not overlapped is the exposed portion of the lower folded portion, and an uncoated area where an outer patch is not attached is formed in the exposed portion of the lower folded portion, and an outer patch is attached to the portion of the exposed portion of the lower folded portion adjacent to the uncoated area via spot adhesive. In the paper bag according to the present disclosure, the uncoated area is located at the end of the exposed portion of the lower folded portion on the side of the lower fold. In the paper bag according to the present disclosure, the uncoated area is positioned away from the lower paper fold in the exposed portion of the lower paper fold. The paper bag according to the present disclosure comprises a tubular bag body having a tubular portion and an opening portion for opening and closing the opening of the tubular portion, and an outer patch provided in the opening portion, the opening portion having a bottom paper and a top paper which are integrally provided on the tubular portion and overlap each other to close the opening, the bottom paper having a bottom paper base and a bottom paper fold portion provided on the bottom paper base, the top paper having an top paper base and an top paper fold portion provided on the top paper base, the inner surface of the bottom paper fold portion is bonded to the bottom paper base and the top paper base via opening glue, and the inner surface of the top paper fold portion is bonded to the outer surfaces of the top paper base, the bottom paper base and the bottom paper fold portion via opening glue. The outer patch is attached to the outer surfaces of the upper paper base, lower paper base and upper paper fold using an opening glue and is attached to the outer surface of the lower paper fold using a fixing glue, the boundary line between the lower paper base and the lower paper fold is the lower paper fold, the boundary line between the upper paper base and the upper paper fold is the upper paper fold, the portion between the lower paper fold and the upper paper fold in the lower paper base and upper paper base that is not overlapped by either the lower paper fold or the upper paper fold is the exposed portion of the lower paper upper paper base, and the outer patch is attached to a portion of the exposed portion of the lower paper upper paper base using a spot fixing glue. In the paper bag according to the present disclosure, the end of the outer patch in the width direction of the paper bag is attached to the portion where spot adhesive glue is applied in the exposed portion of the lower paper and upper paper base. In the paper bag of the present disclosure, an uncoated area where no outer patch is attached is formed on the outer surface of the upper paper fold, and an outer patch is attached via spot adhesive to the portion adjacent to the uncoated area on the outer surface of the upper paper fold. In the paper bag according to the present disclosure, the uncoated area is located at the end of the outer surface of the upper folded portion on the side of the upper fold. In the paper bag according to the present disclosure, the uncoated area is located away from the upper paper crease on the outer surface of the upper paper fold. The method for manufacturing a paper bag according to the present disclosure includes a step of forming a bottom paper and a top paper by folding a tubular body flat, forming a fold line of the tubular body parallel to one open end at a position a preset distance from one open end of the folded tubular body toward the other open end, and folding both of a pair of corners at one open end into the inside of the tubular body up to the fold line of the tubular body to form a bottom paper and a top paper; forming a fold line of the bottom paper parallel to the fold line of the tubular body in the bottom paper, forming a fold line of the top paper parallel to the fold line of the tubular body in the top paper, and sealing the bottom paper base and the top paper base with an opening glue. The method includes a lower paper-upper paper bonding process in which the inner surface of the lower paper folding part is bonded to the paper base and the inner surface of the upper paper folding part is bonded to the outer surfaces of the upper paper base, the lower paper base, and the lower paper folding part using an opening glue, and an outer patch bonding process in which an outer patch is bonded to the outer surfaces of the upper paper base, the lower paper base, and the lower paper folding part using an opening glue, and the outer patch is bonded to the outer surface of the upper paper folding part using a fixing glue, and in the outer patch bonding process, the outer patch is bonded to a portion of the exposed portion of the lower paper upper paper base using a spot fixing glue. The method for manufacturing a paper bag according to the present disclosure includes a step of forming a bottom paper and a top paper by folding a tubular body flat, forming a fold line of the tubular body parallel to one open end at a position a preset distance from one open end of the folded tubular body toward the other open end, and folding both of a pair of corners at one open end into the inside of the tubular body up to the fold line of the tubular body to form a bottom paper and a top paper; forming a fold line of the bottom paper parallel to the fold line of the tubular body in the bottom paper, forming a fold line of the top paper parallel to the fold line of the tubular body in the top paper, and sealing the bottom paper base and the top paper base with an opening glue. The method includes a lower paper-upper paper bonding process in which the inner surface of the lower paper folding portion is bonded to the paper base and the inner surface of the upper paper folding portion is bonded to the outer surfaces of the upper paper base, the lower paper base, and the lower paper folding portion using an opening glue, and an outer patch bonding process in which an outer patch is bonded to the outer surfaces of the upper paper base, the lower paper base, and the upper paper folding portion using an opening glue, and the outer patch is bonded to the outer surface of the lower paper folding portion using a fixing glue, and in the outer patch bonding process, the outer patch is bonded to a portion of the exposed portion of the lower paper upper paper base using a spot fixing glue. Effect of the Invention

[0007] According to the paper bag and the manufacturing method thereof disclosed herein, it is possible to prevent the outer patch from entering the inside of the tubular portion as a foreign object after the opening of the tubular portion is opened. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a plan view showing a paper bag according to embodiment 1. [Diagram 2] FIG. 2 is an enlarged view showing a main part of the paper bag of FIG. [Diagram 3] 3 is a front view showing a main part of the tubular bag body of FIG. 2. [Figure 4] FIG. 4 is a front view showing a state in which the opening portion of FIG. 3 is open. [Diagram 5] 5 is a plan view showing a cylindrical body on which the tube portion, the lower paper and the upper paper of FIG. 4 are formed. [Figure 6] 5 is a plan view showing the state in which an opening glue is applied to the lower paper and an opening glue is applied to the upper paper in FIG. 4. [Figure 7] 4 is a plan view showing a state in which an opening glue is applied to the bottom and top sheets of FIG. 3 and an adhesive glue is applied to the top sheet. [Figure 8] 4 is a flowchart showing a method for manufacturing a paper bag according to the first embodiment. [Figure 9] FIG. 11 is a plan view showing the main parts of a paper bag according to embodiment 2. [Figure 10] 10 is a front view showing a main part of the tubular bag body of FIG. 9. [Figure 11] FIG. 10 is a side view showing a main part of the paper bag of FIG. [Figure 12] FIG. 11 is a plan view showing the state in which the bottom and top sheets of FIG. 10 have been coated with opening glue and opening glue, and the top sheet has been coated with adhesive glue. [Figure 13] A front view showing the main parts of a paper bag according to embodiment 3. [Figure 14] FIG. 11 is a front view showing the main parts of a paper bag according to embodiment 4. [Figure 15] A front view showing the main parts of a paper bag according to embodiment 5. [Figure 16] A front view showing the main parts of a paper bag according to embodiment 6. [Figure 17] A front view showing the main parts of a paper bag according to embodiment 7. [Figure 18] FIG. 23 is a front view showing a main part of a first modified example of the paper bag according to embodiment 6. [Figure 19] FIG. 23 is a front view showing a main part of a second modified example of the paper bag according to embodiment 6. [Figure 20] FIG. 23 is a front view showing a main part of a third modified example of the paper bag according to embodiment 6. [Figure 21] A front view showing a main part of a fourth modified example of the paper bag according to embodiment 6. [Figure 22] A front view showing a main part of a fifth modified example of the paper bag relating to embodiment 6. [Diagram 23] FIG. 13 is a front view showing the main parts of a paper bag according to embodiment 8. [Figure 24] A front view showing the main parts of a paper bag according to embodiment 9. [Diagram 25] FIG. 23 is a front view showing a main part of a first modified example of the paper bag according to embodiment 8. [Figure 26] FIG. 23 is a front view showing a main part of a second modified example of the paper bag according to embodiment 8. [Figure 27] FIG. 23 is a front view showing a main part of a third modified example of the paper bag according to embodiment 8. [Figure 28] FIG. 23 is a front view showing a main part of a fourth modified example of the paper bag according to embodiment 8. [Figure 29] FIG. 23 is a front view showing a main part of a fifth modified example of the paper bag according to embodiment 8. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Embodiment 1 Fig. 1 is a plan view showing a paper bag according to embodiment 1. Fig. 2 is an enlarged view showing a main part of the paper bag of Fig. 1. The paper bag according to embodiment 1 includes a tubular bag body 1 and a pair of outer patches 2. The tubular bag body 1 is made of two sheets of craft paper stacked on top of each other in the thickness direction. In other words, the tubular bag body 1 is made of two layers of craft paper.

[0010] The tubular bag 1 is not limited to being made of two layers of craft paper, but may be made of, for example, three layers of craft paper. The tubular bag 1 may also be made of craft paper, polyethylene film, and craft paper stacked in this order.

[0011] The basis weight of each of the two sheets of craft paper constituting the tubular bag 1 is 78 g / m 2 The basis weight of the outer patch 2 is 78 g / m 2 It is desirable that this is the case.

[0012] Fig. 3 is a front view showing a main part of the cylindrical bag 1 of Fig. 2. The cylindrical bag 1 has a cylindrical portion 101 and an opening portion 102. An opening 103 is formed in the cylindrical portion 101. An object is placed inside the cylindrical portion 101 through the opening 103. An example of the object placed inside the cylindrical portion 101 is powder or granular material. Examples of the powder or granular material include wheat flour, buckwheat flour, rice flour, sugar, cornstarch, and starch.

[0013] The tearable portion 102 is provided on the tubular portion 101. The tearable portion 102 opens and closes the opening 103. The tearable portion 102 is deformed to open and close the opening 103. The tearable portion 102 is provided with an outer patch 2. The outer patch 2 prevents the tearable portion 102 from deforming. FIG. 3 shows a state in which the opening 103 is closed by the tearable portion 102.

[0014] Fig. 4 is a front view showing the state in which the opening 103 of Fig. 3 is open. The opening portion 102 has a lower paper 104 and an upper paper 105. The lower paper 104 and the upper paper 105 are each formed integrally with the tube portion 101. The opening 103 is closed by the lower paper 104 and the upper paper 105 overlapping each other.

[0015] The bottom paper 104 has a bottom paper base 106 and a bottom paper fold portion 107. The bottom paper base 106 is provided on the tube portion 101. The bottom paper fold portion 107 is provided on the bottom paper base 106. The bottom paper 104 has a bottom paper fold line 108 formed as a boundary line between the bottom paper base 106 and the bottom paper fold portion 107.

[0016] The bottom paper 104 is folded around the bottom paper crease 108, so that the bottom paper base 106 and the bottom paper fold 107 overlap each other. The surface of the bottom paper fold 107 that faces the bottom paper base 106 when the bottom paper 104 is folded is referred to as the inner surface 109. The surface of the bottom paper fold 107 opposite the inner surface 109 is referred to as the outer surface 110.

[0017] The upper paper 105 has an upper paper base 111 and an upper paper folded portion 112. The upper paper base 111 is provided on the tube portion 101. The upper paper folded portion 112 is provided on the upper paper base 111. The upper paper 105 has an upper paper crease 113 that serves as a boundary line between the upper paper base 111 and the upper paper folded portion 112.

[0018] The upper paper 105 is folded around the upper paper crease 113, so that the upper paper base 111 and the upper paper folded portion 112 are overlapped with each other. The surface of the upper paper folded portion 112 that faces the upper paper base 111 when the upper paper 105 is folded is defined as the inner surface 114. The surface of the upper paper folded portion 112 opposite the inner surface 114 is defined as the outer surface 115.

[0019] When the lower paper 104 is folded, the end of the lower paper folding section 107 opposite the lower paper crease 108 is overlapped with the upper paper crease 113. This increases the overlapping area between the inner surface 109 of the lower paper folding section 107 and the lower paper base 106 and upper paper base 111.

[0020] When the upper paper 105 is folded, the end of the upper paper folding portion 112 opposite the upper paper crease 113 is overlapped with the lower paper crease 108. This increases the overlapping area between the inner surface 114 of the upper paper folding portion 112 and the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107.

[0021] Fig. 5 is a plan view showing the tubular body 3 in which the tubular portion 101, the lower paper 104, and the upper paper 105 of Fig. 4 are formed. The tubular body 3 that has been flattened is folded to form the tubular portion 101, the lower paper 104, and the upper paper 105.

[0022] A tubular body fold 303 is formed at a position a preset distance from one open end 301 toward the other open end 302 of the crushed tubular body 3. The tubular body fold 303 is parallel to both the lower paper fold 108 and the upper paper fold 113. The tubular body fold 303 becomes the boundary line between the tube portion 101 and the opening portion 102.

[0023] A pair of corners 304 at one opening end 301 are folded inward of the cylindrical body 3 up to a cylindrical fold 303 to form a bottom sheet 104 and an top sheet 105 .

[0024] The width direction of the cylindrical body 3 that has been flattened is the width direction D1 of the paper bag. The portions of both sides of the cylindrical body 3 in the width direction D1 between one opening end 301 and the cylindrical body fold 303 are overlapped with the cylindrical body fold 303 by folding a pair of corners 304 inward of the cylindrical body 3.

[0025] A pair of triangular portions 116 are formed by folding the pair of corner portions 304 inwardly of the cylindrical body 3. The pair of triangular portions 116 are disposed apart from each other in the width direction D1. Each of the triangular portions 116 constitutes a part of the lower sheet 104 and a part of the upper sheet 105.

[0026] 6 is a plan view showing the state in which opening glue has been applied to the bottom paper 104 and the top paper 105 in FIG. 4. Opening glue 117 is applied to the portion included in the triangular portion 116 on the inner surface 109 of the bottom paper folding portion 107. The inner surface 109 of the bottom paper folding portion 107 is bonded to the bottom paper base 106 and the top paper base 111 via the opening glue 117. By bonding the bottom paper folding portion 107 to the bottom paper base 106 and the top paper base 111, the opening 103 is closed.

[0027] An opening glue 118 is applied to the portion of the inner surface 114 of the upper paper folding portion 112 that is included in the triangular portion 116. An opening glue 119 is applied to the portion of the inner surface 114 of the upper paper folding portion 112 that is not included in the triangular portion 116 and is opposite the upper paper crease 113. The inner surface 114 of the upper paper folding portion 112 is bonded to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via the opening glue 118 and the opening glue 119. By bonding the upper paper folding portion 112 to the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107, the lower paper folding portion 107 is prevented from peeling off from the lower paper base 106 and the upper paper base 111.

[0028] Examples of the opening glue 117, the opening glue 118, and the opening glue 119 include vinyl acetate adhesives.

[0029] 7 is a plan view showing a state in which the lower paper 104 and the upper paper 105 in FIG. 3 are coated with opening glue and the upper paper 105 is coated with adhesive glue. Opening glue 120 is applied to the portion between the lower paper fold 108 and the upper paper fold 113 in each of the lower paper base 106 and the upper paper base 111, where neither the lower paper fold 107 nor the upper paper fold 112 overlaps. Opening glue 121 is applied to the portion of the outer surface 110 of the lower paper fold 107 where the upper paper fold 112 does not overlap. The outer patch 2 is attached to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107 via the opening glue 120 and the opening glue 121.

[0030] As the opening glue 120 and the opening glue 121, similar to the opening glue 117, the opening glue 118, and the opening glue 119, for example, a vinyl acetate-based adhesive can be used.

[0031] An adhesive glue 122 is applied to the entire outer surface 115 of the upper paper folding portion 112. The outer patch 2 is attached to the outer surface 115 of the upper paper folding portion 112 via the adhesive glue 122. By attaching the outer patch 2 and the upper paper folding portion 112 via the adhesive glue 122, peeling of the outer patch 2 from the upper paper folding portion 112 is suppressed.

[0032] By bonding the outer patch 2 to the lower paper base 106, the upper paper base 111, the lower paper fold 107 and the upper paper fold 112, the upper paper fold 112 is prevented from peeling off from the upper paper base 111, the lower paper base 106 and the lower paper fold 107.

[0033] In other words, when the opening portion 102 closes the opening 103, the outer patch 2 is attached to the lower paper base 106, the upper paper base 111, the lower paper fold portion 107 and the upper paper fold portion 112, thereby preventing the opening portion 102 from deforming in such a way that the opening 103 opens.

[0034] When opening the opening 103, the worker first grasps the portion of the outer patch 2 that is attached to the center of the width direction D1 on the side opposite the upper fold 113 of the upper fold 112. In this state, the worker peels the outer patch 2 from the outer surfaces 110 of the upper base 111, the lower base 106, and the lower fold 107. This causes the inner surface 114 of the upper fold 112 to be peeled off from the outer surfaces 110 of the upper base 111, the lower base 106, and the lower fold 107. After that, the worker grasps the portion of the lower fold 107 that is opposite the lower fold 108, and is the center of the width direction D1. In this state, the worker peels off the inner surface 109 of the lower fold 107 from the lower base 106 and the upper base 111. This opens the opening 103.

[0035] Next, the procedure for assembling the paper bag according to the first embodiment will be described. Fig. 8 is a flowchart showing the method for manufacturing the paper bag according to the first embodiment. Fig. 8 shows the procedure for closing the opening portion 102 and attaching the outer patch 2 in the method for manufacturing the paper bag. First, in step S101, a bottom paper and top paper forming process is performed.

[0036] In the bottom paper / top paper forming process, the cylindrical body 3 is folded flat, and a cylindrical body crease 303 parallel to one opening end 301 is formed at a position a predetermined distance from one opening end 301 of the folded cylindrical body 3 toward the other opening end 302.

[0037] In the lower paper / upper paper forming process, the lower paper 104 and the upper paper 105 are formed by folding both of a pair of corners 304 at one opening end 301 into the inside of the cylindrical body 3 up to the cylindrical body fold 303.

[0038] Then, in step S102, a bottom paper-top paper bonding process is performed. In the bottom paper-top paper bonding process, a bottom paper fold 108 is formed in the bottom paper 104, which is parallel to the cylindrical body fold 303 and serves as a boundary between the bottom paper base 106 and the bottom paper fold 107.

[0039] In addition, in the lower paper and upper paper bonding process, an upper paper fold 113 that is parallel to the cylindrical body fold 303 and serves as a boundary line between the upper paper base portion 111 and the upper paper folded portion 112 is formed in the upper paper 105.

[0040] In addition, in the lower paper and upper paper bonding process, the inner surface 109 of the lower paper folded portion 107 is bonded to the lower paper base portion 106 and the upper paper base portion 111 via the opening glue 117.

[0041] In addition, in the lower paper and upper paper bonding process, the inner surface 114 of the upper paper fold 112 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106 and the lower paper fold 107 via the opening glue 118 and the opening glue 119.

[0042] Then, in step S103, an outer patch bonding process is performed. In the outer patch bonding process, the outer patch 2 is bonded to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107 via the opening glue 120 and the opening glue 121, and the outer patch 2 is bonded to the outer surface 115 of the upper paper fold 112 via the adhesive glue 122. This completes the paper bag assembly procedure according to the first embodiment.

[0043] As described above, the paper bag according to the first embodiment includes a tubular bag body 1 and an outer patch 2. The tubular bag body 1 includes a tubular portion 101 and an opening portion 102 that opens and closes an opening 103 of the tubular portion 101. The outer patch 2 is provided in the opening portion 102. The opening portion 102 includes a bottom paper 104 and an upper paper 105. The bottom paper 104 and the upper paper 105 are integrally provided in the tubular portion 101. The bottom paper 104 and the upper paper 105 overlap each other to close the opening 103 of the tubular portion 101. The bottom paper 104 includes a bottom paper base 106 and a bottom paper folding portion 107 provided in the bottom paper base 106. The upper paper 105 includes an upper paper base 111 and an upper paper folding portion 112 provided in the upper paper base 111. The inner surface 109 of the lower folding portion 107 is attached to the lower paper base 106 and the upper paper base 111 via an opening glue 117. The inner surface 114 of the upper folding portion 112 is attached to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower folding portion 107 via an opening glue 118 and an opening glue 119. The outer patch 2 is attached to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower folding portion 107 via an opening glue 120 and an opening glue 121. The outer patch 2 is also attached to the outer surface 115 of the upper folding portion 112 via an adhesive glue 122. According to this configuration, the outer patch 2 is attached to the outer surface 115 of the upper folding portion 112 via the adhesive glue 122. As a result, when an operator deforms the tearing portion 102 to open the opening 103 of the tubular portion 101, the outer patch 2 remains attached to the upper paper 105. Therefore, it is possible to prevent the outer patch 2 from entering the inside of the tubular portion 101 as a foreign object after the opening 103 of the tubular portion 101 is opened.

[0044] Also, with this configuration, the inner surface 109 of the lower folding portion 107 is attached to the lower paper base 106 and the upper paper base 111 via the opening glue 117. This allows the worker to easily peel the inner surface 109 of the lower folding portion 107 from the lower paper base 106 and the upper paper base 111. Also, the generation of paper dust when peeling the inner surface 109 of the lower folding portion 107 from the lower paper base 106 and the upper paper base 111 can be suppressed.

[0045] Furthermore, according to this configuration, the inner surface 114 of the upper paper folding portion 112 is attached to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via the opening glue 118 and the opening glue 119. This allows the worker to easily peel the inner surface 114 of the upper paper folding portion 112 from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107. It is also possible to prevent paper dust from being generated when peeling the inner surface 114 of the upper paper folding portion 112 from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107.

[0046] Furthermore, with this configuration, the outer patch 2 is attached to the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via the opening glue 120 and the opening glue 121. This allows the worker to easily peel the outer patch 2 from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107. It is also possible to prevent paper dust from being generated when peeling the outer patch 2 from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107.

[0047] Furthermore, with this configuration, by peeling the outer patch 2 from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107, the inner surface 114 of the upper paper fold 112 can be peeled off from the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107. This allows the process of peeling off the outer patch 2 and the process of peeling off the upper paper fold 112 to be performed simultaneously. As a result, the process of opening the paper bag can be simplified.

[0048] The method for manufacturing a paper bag according to the first embodiment includes a bottom paper and top paper forming step, a bottom paper and top paper pasting step, and an outer patch pasting step. In the bottom paper and top paper forming step, the cylindrical body 3 is folded flat, and a cylindrical body fold 303 parallel to one opening end 301 is formed at a position a preset distance away from one opening end 301 of the folded cylindrical body 3 toward the other opening end 302. In the bottom paper and top paper forming step, both of a pair of corners 304 at one opening end 301 are folded inward of the cylindrical body 3 up to the cylindrical body fold 303 to form the bottom paper 104 and the top paper 105. In the bottom paper and top paper pasting step, a bottom paper fold 108 is formed in the bottom paper 104, which is parallel to the cylindrical body fold 303 and serves as a boundary between the bottom paper base 106 and the bottom paper fold 107. In the lower paper-upper paper bonding process, an upper paper crease 113 is formed in the upper paper 105, which is parallel to the cylindrical body crease 303 and serves as a boundary between the upper paper base 111 and the upper paper folded portion 112. In the lower paper-upper paper bonding process, the inner surface 109 of the lower paper folded portion 107 is bonded to the lower paper base 106 and the upper paper base 111 via an opening glue 117. In the lower paper-upper paper bonding process, the inner surface 114 of the upper paper folded portion 112 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folded portion 107 via an opening glue 118 and an opening glue 119. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folded portion 107 via an opening glue 120 and an opening glue 121. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 115 of the upper paper folded portion 112 via the adhesive glue 122. According to this configuration, the outer patch 2 is bonded to the outer surface 115 of the upper paper folded portion 112 via the adhesive glue 122. As a result, when the worker deforms the tearing portion 102 to open the opening 103 of the tube portion 101, the outer patch 2 remains bonded to the upper paper 105. Therefore, it is possible to prevent the outer patch 2 from entering the inside of the tube portion 101 as a foreign object after the opening 103 of the tube portion 101 is opened.

[0049] Embodiment 2 Fig. 9 is a plan view showing a main part of a paper bag according to embodiment 2. Fig. 10 is a front view showing a main part of the tubular bag body of Fig. 9. Fig. 11 is a side view showing a main part of the paper bag of Fig. 9. End 123 of lower folded portion 107 on the opposite side to lower crease 108 is positioned closer to lower crease 108 than upper crease 113. End 124 of upper folded portion 112 on the opposite side to upper crease 113 is positioned closer to upper crease 113 than lower crease 108.

[0050] 11 shows a state in which powder and granular material are contained inside the paper bag. By containing the powder and granular material inside the paper bag, the crushed cylindrical body 3 becomes larger in the thickness direction. As a result, when the paper bag is viewed from the side, a corner is formed at the lower paper crease 108. When the end 124 of the upper paper fold 112 opposite the upper paper crease 113 is overlapped with the lower paper crease 108, the end 124 of the upper paper fold 112 opposite the upper paper crease 113 is overlapped with the corner of the paper bag.

[0051] When an external force acts on the paper bag in the thickness direction of the paper bag, the corner of the paper bag deforms in a direction that increases the angle of the corner. When the corner of the paper bag deforms with end 124 of upper paper fold 112 opposite upper paper crease 113 overlapping the corner of the paper bag, an external force acts on upper paper fold 112 so that upper paper fold 112 moves away from lower paper crease 108.

[0052] An end 124 of the upper folded portion 112 opposite the upper crease 113 is positioned closer to the upper crease 113 than the lower crease 108. This prevents the upper folded portion 112 from peeling off from the outer surface 110 of the lower folded portion 107 even if deformation occurs at the corner of the paper bag.

[0053] Figure 12 is a plan view showing the state in which opening glue 120 and opening glue 121 are applied to the bottom paper 104 and top paper 105 of Figure 10, and adhesive glue 122 is applied to the top paper 105. The portion of the outer surface 115 of the top paper folding section 112 that is adjacent to the outer surfaces 110 of the top paper base 111, the bottom paper base 106, and the bottom paper folding section 107 when viewed perpendicularly to the outer surface 115 of the top paper folding section 112 is defined as the top paper folding section outer surface peripheral portion 125. Opening glue 126 is applied to the entire area of ​​the top paper folding section outer surface peripheral portion 125. Adhesive glue 122 is not applied to the top paper folding section outer surface peripheral portion 125.

[0054] When the outer patch 2 is attached to the outer surface 115 of the upper paper folding portion 112, the adhesive glue 122 spreads to penetrate between the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2. However, by applying the opening glue 126 to the peripheral portion 125 of the outer surface of the upper paper folding portion, the adhesive glue 122 is prevented from penetrating between the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2.

[0055] In other words, an opening glue 126 is provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2 to prevent the adhesive glue 122 from penetrating between the outer surfaces 110 of the upper paper base 111, the lower paper base 106 and the lower paper folding portion 107 and the outer patch 2.

[0056] Other configurations of the paper bag according to the second embodiment are similar to those of the paper bag according to the first embodiment.

[0057] As described above, in the paper bag according to the second embodiment, the opening glue 126 is provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2. The opening glue 126 prevents the adhesive glue 122 provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2 from penetrating between the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2. This configuration prevents the adhesive glue 122 provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2 from penetrating between the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2. This prevents the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 from being stuck to each other by the adhesive glue 122.

[0058] In the paper bag according to the second embodiment, the configuration has been described in which the opening glue 126 is provided on the entire area of ​​the outer peripheral portion 125 of the upper paper folding portion. However, it is sufficient that the opening glue 126 is provided on at least a part of the outer peripheral portion 125 of the upper paper folding portion. Even if the opening glue 126 is provided on only a part of the outer peripheral portion 125 of the upper paper folding portion, it is possible to prevent the adhesive glue 122 from penetrating between the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2.

[0059] Embodiment 3 Fig. 13 is a front view showing a main part of the paper bag according to embodiment 3. Fig. 13 shows the main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. The part between the lower paper fold 108 and the upper paper fold 113 in each of the lower paper base 106 and the upper paper base 111, which is not overlapped by either the lower paper fold 107 or the upper paper fold 112, is the lower paper upper paper base exposed part 127.

[0060] An adhesive glue 128 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper. An opening glue 120 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper that is not coated with the adhesive glue 128. When viewed perpendicularly to the outer patch 2, the outer patch 2 is attached to the exposed portion 127 of the upper paper base of the lower paper via the adhesive glue 128 and the opening glue 120.

[0061] The portion of the lower paper upper paper base exposed portion 127 to which the adhesive 128 is applied is formed small enough that an operator can peel the outer patch 2 off the lower paper upper paper base exposed portion 127 when opening the opening 103.

[0062] The portion of the outer surface 110 of the lower folded portion 107 where the upper folded portion 112 is not overlapped is referred to as an exposed portion 129 of the lower folded portion.

[0063] Adhesive glue 130 is applied to a portion of lower folded exposed portion 129. Opening glue 121 is applied to a portion of lower folded exposed portion 129 that is not coated with adhesive glue 130. When viewed perpendicularly to outer patch 2, outer patch 2 is attached to lower folded exposed portion 129 via adhesive glue 130 and opening glue 121.

[0064] The portion of the lower folded portion exposed portion 129 to which the adhesive glue 130 is applied is formed small enough that an operator can peel off the outer patch 2 from the lower folded portion exposed portion 129 when opening the opening 103.

[0065] The end of the outer surface 115 of the upper paper folding portion 112 opposite the upper paper crease 113 is the upper paper folding portion outer surface tip 131. A fixing glue 132 is applied to a part of the upper paper folding portion outer surface tip 131. An opening glue 133 is applied to the part of the upper paper folding portion outer surface tip 131 where the fixing glue 132 is not applied. As with the opening glue 120 and the opening glue 121, the opening glue 133 may be, for example, a vinyl acetate adhesive.

[0066] The portion of the upper paper folding portion outer surface tip 131 to which the adhesive glue 132 is applied is formed small enough that an operator can peel the outer patch 2 off the upper paper folding portion outer surface tip 131 when opening the opening 103.

[0067] An adhesive glue 122 is applied to the outer surface 115 of the upper folded portion 112 other than the tip portion 131 of the outer surface of the upper folded portion.

[0068] An uncoated area 134 where neither the adhesive glue 132 nor the opening glue 133 is applied is formed at the end of the upper paper folding portion outer surface tip 131 opposite the upper paper fold 113. The uncoated area 134 is located in the middle of the width direction D1 of the paper bag at the upper paper folding portion outer surface tip 131. The uncoated area 134 is not affixed to the outer patch 2. This allows the worker to easily grasp the portion of the outer patch 2 that overlaps the uncoated area 134.

[0069] The other configurations of the paper bag according to embodiment 3 are the same as those of the paper bag according to embodiment 1. As with the paper bag according to embodiment 2, an opening glue 126 is provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2, and the opening glue 126 may be configured to prevent the adhesive glue 122 provided between the outer surface 115 of the upper paper folding portion 112 and the outer patch 2 from penetrating between the outer surfaces 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 and the outer patch 2.

[0070] As described above, in the paper bag according to the third embodiment, the outer patch 2 is attached to the tip 131 of the outer surface of the upper paper folding portion via the opening glue 133, and is attached to the outer surface 115 of the upper paper folding portion 112 other than the tip 131 of the outer surface of the upper paper folding portion via the adhesive glue 122. With this configuration, the worker can easily peel the outer patch 2 from the tip 131 of the outer surface of the upper paper folding portion. By the worker grabbing the part of the outer patch 2 peeled off from the outer surface 115 of the upper paper folding portion 112, the worker can easily peel the inner surface 114 of the upper paper folding portion 112 from the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107.

[0071] In the paper bag according to the third embodiment, the uncoated area 134 is disposed in the middle of the tip 131 of the upper folded outer surface in the width direction D1 of the paper bag. However, the uncoated area 134 may be disposed in any part of the tip 131 of the upper folded outer surface in the width direction D1 of the paper bag.

[0072] Embodiment 4 Fig. 14 is a front view showing a main part of a paper bag according to embodiment 4. Fig. 14 shows a main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. An adhesive glue 135 is applied to the tip 131 of the outer surface of the upper folded portion. An opening glue 136 is applied to the outer surface 115 of the upper folded portion 112 other than the tip 131 of the outer surface of the upper folded portion. As with the opening glue 120 and the opening glue 121, the opening glue 136 may be, for example, a vinyl acetate adhesive.

[0073] When opening the opening 103, the worker first grasps the portion of the outer patch 2 that is attached to the center of the width direction D1 on the side of the upper fold 113 of the upper fold 112. In this state, the worker peels off the outer patch 2 from the outer surface 110 of the upper base 111, the lower base 106, and the lower fold 107, and the outer surface 115 of the upper fold 112, except for the tip 131 of the outer surface of the upper fold. This causes the inner surface 114 of the upper fold 112 to be peeled off from the outer surface 110 of the upper base 111, the lower base 106, and the lower fold 107. Then, the worker grasps the portion of the lower fold 107 opposite the lower fold 108, which is the center of the width direction D1. In this state, the worker peels off the inner surface 109 of the lower fold 107 from the lower base 106 and the upper base 111. This opens the opening 103 .

[0074] Other configurations of the paper bag according to the fourth embodiment are similar to those of the paper bag according to the first embodiment.

[0075] As described above, according to the paper bag of the fourth embodiment, the outer patch 2 is attached to the tip 131 of the outer surface of the upper paper folding portion via the adhesive glue 135, and is attached to the outer surface 115 of the upper paper folding portion 112 other than the tip 131 of the outer surface of the upper paper folding portion via the opening glue 136. With this configuration, the worker can peel off the outer patch 2 from the part of the outer surface 115 of the upper paper folding portion 112 other than the tip 131 of the outer surface of the upper paper folding portion. By the worker grabbing the part of the outer patch 2 peeled off from the outer surface 115 of the upper paper folding portion 112, the worker can easily peel off the inner surface 114 of the upper paper folding portion 112 from the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107.

[0076] Embodiment 5. Fig. 15 is a front view showing a main part of a paper bag according to embodiment 5. Fig. 15 shows a main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. An end 124 of the upper folded portion 112 on the opposite side to the upper crease 113 is positioned closer to the upper crease 113 than the lower crease 108.

[0077] The portion of the outer surface 110 of the lower folding portion 107 where the upper folding portion 112 is not overlapped and which is on the side of the lower crease 108 is designated as the lower folding portion outer surface base end 137. The lower folding portion outer surface base end 137 is coated with adhesive glue 138. The adhesive glue 138 is applied to the entire area of ​​the lower folding portion outer surface base end 137 in the width direction D1 of the paper bag. The portion of the outer surface 110 of the lower folding portion 107 where the upper folding portion 112 is not overlapped and which is on the side of the lower folding portion outer surface base end 137 is coated with opening glue 121.

[0078] When opening the opening 103, the worker first grasps the portion of the outer patch 2 that is attached to the central portion of the width direction D1 on the upper paper folding portion 112 at the side of the upper paper fold 113. In this state, the worker peels off the outer patch 2 from the portion of the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 other than the lower paper folding portion outer surface base end 137, and from the outer surface 115 of the upper paper folding portion 112. Then, the worker grasps the portion of the upper paper folding portion 112 opposite the upper paper fold 113 and the central portion of the width direction D1. In this state, the worker peels off the inner surface 114 of the upper paper folding portion 112 from the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107. Then, the worker grasps the portion of the lower paper folding portion 107 opposite the lower paper fold 108 and the central portion of the width direction D1. In this state, the worker peels the inner surface 109 of the lower folded portion 107 from the lower base portion 106 and the upper base portion 111. This opens the opening 103.

[0079] The procedure for assembling the paper bag according to the fifth embodiment differs from the procedure for assembling the paper bag according to the first embodiment in the outer patch pasting process. In the outer patch pasting process, the outer patch 2 is pasted to the portion of the outer surface 115 of the upper paper folding portion 112 other than the base end portion 137 of the outer surface of the lower paper folding portion on the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 where the upper paper folding portion 112 is not overlapped, using the opening glue 120, the opening glue 121, and the opening glue 136, and the outer patch 2 is pasted to the base end portion 137 of the outer surface of the lower paper folding portion on the outer surface 110 of the lower paper folding portion 107 using the adhesive glue 138.

[0080] Other configurations of the paper bag according to the fifth embodiment are similar to those of the paper bag according to the fourth embodiment.

[0081] As described above, in the paper bag according to the fifth embodiment, the outer patch 2 is attached to the outer surface 115 of the upper paper base 111, the lower paper base 106, and the upper paper fold 112 via the opening glue 120 and the opening glue 136, and is attached to the outer surface base end 137 of the lower paper fold outer surface of the outer surface 110 of the lower paper fold 107 via the adhesive glue 138. According to this configuration, the outer patch 2 is attached to the outer surface 110 of the lower paper fold 107 via the adhesive glue 138. As a result, when the worker deforms the opening portion 102 to open the opening 103 of the tube portion 101, the outer patch 2 remains attached to the lower paper 104. Therefore, it is possible to prevent the outer patch 2 from entering the inside of the tube portion 101 as a foreign object after the opening 103 of the tube portion 101 is opened.

[0082] In addition, in the manufacturing method of the paper bag according to the fifth embodiment, in the outer patch pasting process, the outer patch 2 is pasted to the outer surface 115 of the upper paper base 111, the lower paper base 106, and the upper paper fold 112 via the opening glue 120 and the opening glue 136. In addition, in the outer patch pasting process, the outer patch 2 is pasted to the lower paper fold outer surface base end 137 of the outer surface 110 of the lower paper fold 107 via the adhesive glue 138. According to this configuration, the outer patch 2 is pasted to the outer surface 110 of the lower paper fold via the adhesive glue 138. As a result, when the worker deforms the opening portion 102 to open the opening 103 of the tube portion 101, the outer patch 2 remains pasted to the lower paper 104. Therefore, it is possible to prevent the outer patch 2 from entering the inside of the tube portion 101 as a foreign object after the opening 103 of the tube portion 101 is opened.

[0083] Embodiment 6 Fig. 16 is a front view showing a main part of a paper bag according to embodiment 6. Fig. 16 shows a main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. An end 123 of the lower folded portion 107 on the opposite side to the lower crease 108 is positioned closer to the lower crease 108 than the upper crease 113. An end 124 of the upper folded portion 112 on the opposite side to the upper crease 113 is positioned closer to the upper crease 113 than the lower crease 108.

[0084] The portion between the lower fold 108 and the upper fold 113 in the lower paper base 106 and the upper paper base 111, where neither the lower fold 107 nor the upper fold 112 overlaps, is referred to as the lower upper paper base exposed portion 127. The lower upper paper base exposed portion 127 is located at two locations, one on each side in FIG. 16 .

[0085] A spot adhesive glue 139 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper. An opening glue 120 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper that is not coated with the spot adhesive glue 139. The outer patch 2 is attached to the exposed portion 127 of the upper paper base of the lower paper via the spot adhesive glue 139 and the opening glue 120.

[0086] The configuration of the spot adhesive glue 139 is the same as the configuration of the adhesive glue 128 in the paper bag according to embodiment 3. Therefore, the portion of the lower paper upper paper base exposed portion 127 to which the spot adhesive glue 139 is applied is formed small enough that the outer patch 2 can be peeled off from the lower paper upper paper base exposed portion 127 when an operator opens the opening 103. Specifically, the shape of the spot adhesive glue 139 is formed into a rectangle with each side having a length of about several mm.

[0087] The spot adhesive glue 139 is arranged in threes on each of the lower paper upper paper base exposed portions 127. In each of the lower paper upper paper base exposed portions 127, the three spot adhesive glues 139 are arranged in a line in a direction perpendicular to the width direction D1 of the paper bag when viewed perpendicularly to the lower paper upper paper base exposed portion 127.

[0088] The portion of each lower paper upper paper base exposed portion 127 to which the spot adhesive glue 139 is applied is the outer portion of the lower paper upper paper base exposed portion 127 in the width direction D1 of the paper bag. The end portion of the outer patch 2 in the width direction D1 of the paper bag is attached to the portion of each lower paper upper paper base exposed portion 127 to which the spot adhesive glue 139 is applied.

[0089] The portion of the outer surface 110 of the lower folded portion 107 where the upper folded portion 112 is not overlapped is referred to as an exposed portion 129 of the lower folded portion.

[0090] A spot adhesive glue 140 is applied to a portion of the lower folded portion exposed portion 129. An opening glue 121 is applied to a portion of the lower folded portion exposed portion 129 to which the spot adhesive glue 140 is not applied. The outer patch 2 is attached to the outer surface 110 of the lower folded portion 107 via the spot adhesive glue 140 and the opening glue 121.

[0091] The configuration of the spot adhesive glue 140 is the same as the configuration of the adhesive glue 130 in the paper bag according to embodiment 3. Therefore, the portion of the lower folded exposed portion 129 to which the spot adhesive glue 140 is applied is formed small enough that the outer patch 2 can be peeled off from the lower folded exposed portion 129 when an operator opens the opening 103. Specifically, the shape of the spot adhesive glue 140 is formed into a rectangle with each side having a length of about several mm.

[0092] An uncoated area 141 to which the outer patch 2 is not attached is formed in the lower folded exposed portion 129. The uncoated area 141 is located at the end of the lower folded exposed portion 129 on the lower crease 108 side. The uncoated area 141 is located in the middle of the lower folded exposed portion 129 in the width direction D1 of the paper bag. A thumb hole is formed by the uncoated area 141 and the part of the outer patch 2 overlapping the uncoated area 141. The uncoated area 141 is not attached to the outer patch 2. This allows the worker to easily grasp the part of the outer patch 2 overlapping the uncoated area 141.

[0093] When the outer patch 2 is peeled off from the tubular bag body 1, the outer patch 2 is peeled off first from the lower fold 108 and lastly from the upper fold 113. When viewed perpendicularly to the outer patch 2, the direction from the lower fold 108 toward the upper fold 113 is defined as the outer patch peeling direction D2.

[0094] The spot adhesive 140 is disposed in a portion adjacent to the uncoated area 141 in the lower paper folding exposed portion 129. Specifically, the spot adhesive 140 is disposed adjacent to the uncoated area 141 in the outer patch peeling direction D2. Because the uncoated area 141 is not attached to the outer patch 2, the outer patch 2 is easily peeled off from the portion adjacent to the uncoated area 141 in the lower paper folding exposed portion 129. However, because the spot adhesive 140 is disposed in a portion adjacent to the uncoated area 141 in the lower paper folding exposed portion 129, the outer patch 2 is less likely to peel off from the portion adjacent to the uncoated area 141 in the lower paper folding exposed portion 129.

[0095] Other configurations of the paper bag according to the sixth embodiment are similar to those of the paper bag according to the third embodiment.

[0096] As described above, the paper bag according to the sixth embodiment includes a tubular bag body 1 and an outer patch 2. The tubular bag body 1 includes a tubular portion 101 and an opening portion 102 that opens and closes an opening 103 of the tubular portion 101. The outer patch 2 is provided in the opening portion 102. The opening portion 102 includes a bottom paper 104 and an upper paper 105. The bottom paper 104 and the upper paper 105 are integrally provided in the tubular portion 101. The bottom paper 104 and the upper paper 105 overlap each other to close the opening 103 of the tubular portion 101. The bottom paper 104 includes a bottom paper base 106 and a bottom paper folding portion 107 provided in the bottom paper base 106. The upper paper 105 includes an upper paper base 111 and an upper paper folding portion 112 provided in the upper paper base 111. The inner surface 109 of the lower paper folding portion 107 is attached to the lower paper base 106 and the upper paper base 111 via an opening glue 117. The inner surface 114 of the upper paper folding portion 112 is attached to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via an opening glue 118 and an opening glue 119. The outer patch 2 is attached to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via an opening glue 120 and an opening glue 121. The outer patch 2 is also attached to the outer surface 115 of the upper paper folding portion 112 via a fixing glue 122. The boundary line between the lower paper base 106 and the lower paper folding portion 107 is the lower paper fold 108. The boundary line between the upper paper base 111 and the upper paper folding portion 112 is the upper paper fold 113. The portion between the lower fold 108 and the upper fold 113 in the lower paper base 106 and the upper paper base 111, which is not overlapped with either the lower fold 107 or the upper fold 112, is the lower upper paper base exposed portion 127. The outer patch 2 is attached to a part of the lower upper paper base exposed portion 127 via a spot adhesive glue 139. This configuration can improve the strength of the attachment between the lower upper paper base exposed portion 127 and the outer patch 2. This can prevent the outer patch 2 from peeling off from the lower upper paper base exposed portion 127 when the paper bag is carried with contents stored inside the tube portion 101.

[0097] Furthermore, in the paper bag according to embodiment 6, the end of the outer patch 2 in the width direction D1 of the paper bag is attached to the portion where the spot adhesive glue 139 is applied in the lower paper upper paper base exposed portion 127. With this configuration, it is possible to improve the strength of the attachment between the end of the outer patch 2 in the width direction D1 of the paper bag and the lower paper upper paper base exposed portion 127.

[0098] Furthermore, in the paper bag according to embodiment 6, the portion of the outer surface 110 of the lower folded portion 107 where the upper folded portion 112 is not overlapped is defined as the lower folded portion exposed portion 129. The lower folded portion exposed portion 129 has an uncoated area 141 to which the outer patch 2 is not attached. The outer patch 2 is attached to the portion of the lower folded portion exposed portion 129 adjacent to the uncoated area 141 via spot adhesive glue 140. This configuration makes it possible to prevent the outer patch 2 from peeling off from the portion of the lower folded portion exposed portion 129 adjacent to the uncoated area 141.

[0099] In the paper bag according to the sixth embodiment, the uncoated area 141 is disposed at the end of the lower folded exposed portion 129 on the side of the lower fold 108. With this configuration, the worker can easily grasp the portion of the outer patch 2 that overlaps the uncoated area 141.

[0100] The method for manufacturing a paper bag according to the sixth embodiment includes a lower paper and upper paper forming step, a lower paper and upper paper pasting step, and an outer patch pasting step. In the lower paper and upper paper forming step, the cylindrical body 3 is folded flat, and a cylindrical body fold 303 parallel to one opening end 301 is formed at a position a preset distance away from one opening end 301 of the folded cylindrical body 3 toward the other opening end 302. In the lower paper and upper paper forming step, both of a pair of corners 304 at one opening end 301 are folded inward of the cylindrical body 3 up to the cylindrical body fold 303 to form the lower paper 104 and the upper paper 105. In the lower paper and upper paper pasting step, a lower paper fold 108 parallel to the cylindrical body fold 303 is formed in the lower paper 104, and an upper paper fold 113 parallel to the cylindrical body fold 303 is formed in the upper paper 105. In the lower paper-upper paper bonding process, the inner surface 109 of the lower paper fold 107 is bonded to the lower paper base 106 and the upper paper base 111 via an opening glue 117. In the lower paper-upper paper bonding process, the inner surface 114 of the upper paper fold 112 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107 via an opening glue 118 and an opening glue 119. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107 via an opening glue 120 and an opening glue 121. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 115 of the upper paper fold 112 via a fixing glue 122. In the outer patch bonding process, the outer patch 2 is bonded to a portion of the lower paper upper paper base exposed portion 127 via spot adhesive glue 139. This configuration can improve the bonding strength between the lower paper upper paper base exposed portion 127 and the outer patch 2. This can prevent the outer patch 2 from peeling off from the lower paper upper paper base exposed portion 127 when the paper bag is carried with contents stored inside the tube portion 101.

[0101] Embodiment 7 Fig. 17 is a front view showing a main part of a paper bag according to the seventh embodiment. Fig. 17 shows a main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. An uncoated area 142 to which the outer patch 2 is not attached is formed in the lower folded exposed part 129. The uncoated area 142 is located at a position away from the lower paper fold 108 in the lower folded exposed part 129. Specifically, the uncoated area 142 is located away from the lower paper fold 108 in the outer patch peeling direction D2. Therefore, the opening glue 121 is applied between the uncoated area 142 and the lower paper fold 108.

[0102] The opening glue 121 is applied between the uncoated area 142 and the lower paper fold 108, thereby preventing foreign matter from entering the uncoated area 142. In order for an operator to grasp the portion of the outer patch 2 that is overlaid on the uncoated area 142, the operator peels off the outer patch 2 from the portion between the uncoated area 142 and the lower paper fold 108 in the exposed portion 129 of the lower paper fold.

[0103] In the width direction D1 of the paper bag, the dimension of uncoated area 142 in the paper bag according to embodiment 7 is larger than the dimension of uncoated area 141 in the paper bag according to embodiment 6. This allows a worker to easily grasp the portion of outer patch 2 that overlaps uncoated area 142.

[0104] The spot adhesive 140 is disposed in a portion adjacent to the uncoated area 142 in the lower paper folding exposed portion 129. Specifically, the spot adhesive 140 is disposed adjacent to the uncoated area 142 in the outer patch peeling direction D2. Because the uncoated area 142 is not attached to the outer patch 2, the outer patch 2 is easily peeled off from the portion adjacent to the uncoated area 142 in the lower paper folding exposed portion 129. However, because the spot adhesive 140 is disposed in a portion adjacent to the uncoated area 142 in the lower paper folding exposed portion 129, the outer patch 2 is less likely to peel off from the portion adjacent to the uncoated area 142 in the lower paper folding exposed portion 129.

[0105] Other configurations of the paper bag according to the seventh embodiment are similar to those of the paper bag according to the sixth embodiment.

[0106] As described above, in the paper bag according to the seventh embodiment, the uncoated area 142 is disposed at a position away from the lower paper fold 108 in the lower paper fold exposed portion 129. This configuration can prevent foreign matter from entering the uncoated area 142.

[0107] In the paper bags according to the sixth and seventh embodiments, three spot-fixed glues 139 are arranged in each of the lower paper upper paper base exposed portions 127. However, this is not limited to the above. For example, as shown in FIG. 18, two spot-fixed glues 139 may be arranged in each of the lower paper upper paper base exposed portions 127. Also, as shown in FIG. 19, one spot-fixed glue 139 may be arranged in each of the lower paper upper paper base exposed portions 127. Also, as shown in FIG. 20, no spot-fixed glue 139 may be arranged in each of the lower paper upper paper base exposed portions 127.

[0108] In addition, in the paper bags according to the sixth and seventh embodiments, the configuration in which the spot-fixed glue 139 and the spot-fixed glue 140 are each rectangular has been described. However, this is not limited to this. For example, as shown in FIG. 21, at least one of the spot-fixed glue 139 and the spot-fixed glue 140 may be triangular in shape. In this case, the triangular spot-fixed glue 139 and the spot-fixed glue 140 may be arranged so that the dimension in the width direction D1 of the paper bag increases toward the outer patch peeling direction D2. This makes it easier for the worker to peel off the outer patch 2. In addition, the spot-fixed glue 139 and the spot-fixed glue 140 are not limited to triangular shapes, and may be formed so that the dimension in the width direction D1 of the paper bag increases toward the outer patch peeling direction D2. In addition, at least one of the spot-fixed glue 139 and the spot-fixed glue 140 may be round or other shapes.

[0109] Also, in the paper bags according to the sixth and seventh embodiments, a configuration has been described in which the opening glue 120 is uniformly applied to the lower paper upper paper base exposed portion 127. However, this is not limited to this. For example, as shown in FIG. 22, a configuration may be used in which multiple opening glues 120, each formed in a straight line and parallel to each other, are applied to the lower paper upper paper base exposed portion 127. Adjacent opening glues 120 are spaced apart from each other. In this case, the amount of opening glue 120 applied to the lower paper upper paper base exposed portion 127 can be reduced.

[0110] Also, in the paper bags according to the sixth and seventh embodiments, a configuration has been described in which the opening glue 121 is uniformly applied to the lower folded portion exposed portion 129. However, this is not limited to this. For example, as shown in FIG. 22, a configuration may be used in which multiple opening glues 121, each formed in a straight line and parallel to each other, are applied to the lower folded portion exposed portion 129. Adjacent opening glues 121 are spaced apart from each other. In this case, the amount of opening glue 121 applied to the lower folded portion exposed portion 129 can be reduced.

[0111] Also, in the paper bags according to the sixth and seventh embodiments, a configuration has been described in which the adhesive glue 122 is uniformly applied to the outer surface 115 of the upper paper folding section 112. However, this is not limited to this. For example, as shown in FIG. 22, a configuration may be used in which multiple adhesive glues 122, each formed in a straight line and parallel to each other, are applied to the outer surface 115 of the upper paper folding section 112. Adjacent adhesive glues 122 are spaced apart from each other. In this case, the amount of adhesive glue 122 applied to the outer surface 115 of the upper paper folding section 112 can be reduced.

[0112] Also, in the paper bag according to the seventh embodiment, a configuration has been described in which the entire spot-fixed glue 140 is disposed away from the uncoated region 142 in the outer patch peeling direction D2. However, this is not limited to this. For example, the spot-fixed glue 140 may be disposed so that at least a portion thereof is surrounded by the uncoated region 142. Even in this case, the spot-fixed glue 140 is disposed so as to be adjacent to the uncoated region 142 in the outer patch peeling direction D2.

[0113] Embodiment 8 Fig. 23 is a front view showing a main part of a paper bag according to embodiment 8. Fig. 23 shows a main part of the paper bag before the outer patch 2 is attached to the tubular bag body 1. An end 123 of the lower folded portion 107 on the opposite side to the lower crease 108 is positioned closer to the lower crease 108 than the upper crease 113. An end 124 of the upper folded portion 112 on the opposite side to the upper crease 113 is positioned closer to the upper crease 113 than the lower crease 108.

[0114] The portion between the lower fold 108 and the upper fold 113 in the lower paper base 106 and the upper paper base 111, where neither the lower fold 107 nor the upper fold 112 overlaps, is referred to as the lower upper paper base exposed portion 127. In FIG. 23, the lower upper paper base exposed portion 127 is disposed in two locations, one on each side.

[0115] A spot adhesive glue 143 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper. An opening glue 120 is applied to a portion of the exposed portion 127 of the upper paper base of the lower paper that is not coated with the spot adhesive glue 143. The outer patch 2 is attached to the exposed portion 127 of the upper paper base of the lower paper via the spot adhesive glue 143 and the opening glue 120.

[0116] The configuration of the spot adhesive glue 143 is the same as the configuration of the spot adhesive glue 139 in the paper bag according to embodiment 6. Therefore, the portion of the lower paper upper paper base exposed portion 127 to which the spot adhesive glue 143 is applied is formed small enough that the outer patch 2 can be peeled off from the lower paper upper paper base exposed portion 127 when an operator opens the opening 103. Specifically, the shape of the spot adhesive glue 143 is formed into a rectangle with each side having a length of about several mm.

[0117] The spot adhesive glue 143 is arranged in threes on each of the lower paper upper paper base exposed portions 127. In each of the lower paper upper paper base exposed portions 127, the three spot adhesive glues 143 are arranged in a line in a direction perpendicular to the width direction D1 of the paper bag when viewed perpendicularly to the lower paper upper paper base exposed portion 127.

[0118] The portion of each of the exposed portions 127 of the upper paper base of the lower paper sheet where the spot adhesive glue 143 is applied is the outer portion of the exposed portion 127 of the upper paper base of the lower paper sheet in the width direction D1 of the paper bag. The end of the outer patch 2 in the width direction D1 of the paper bag is attached to the portion of each of the exposed portions 127 of the upper paper base of the lower paper sheet where the spot adhesive glue 143 is applied.

[0119] A spot adhesive glue 144 is applied to a portion of the outer surface 115 of the upper folding portion 112. An opening glue 136 is applied to a portion of the outer surface 115 of the upper folding portion 112 where the spot adhesive glue 144 is not applied. The outer patch 2 is attached to the outer surface 115 of the upper folding portion 112 via the spot adhesive glue 144 and the opening glue 136.

[0120] The configuration of the spot adhesive glue 144 is the same as that of the spot adhesive glue 140 according to the sixth embodiment. Therefore, the portion of the outer surface 115 of the upper paper folding portion 112 to which the spot adhesive glue 144 is applied is formed small enough that the outer patch 2 can be peeled off from the outer surface 115 of the upper paper folding portion 112 when an operator opens the opening 103. Specifically, the shape of the spot adhesive glue 144 is formed into a rectangle with each side having a length of about several mm.

[0121] An uncoated area 145 to which the outer patch 2 is not attached is formed in a part of the outer surface 115 of the upper paper folding section 112. The uncoated area 145 is located at the end of the outer surface 115 of the upper paper folding section 112 on the side of the upper paper crease 113. The uncoated area 145 is located in the middle of the outer surface 115 of the upper paper folding section 112 in the width direction D1 of the paper bag. The uncoated area 145 and the part of the outer patch 2 overlapping the uncoated area 145 form a thumb hole. The uncoated area 145 is not attached to the outer patch 2. This allows the worker to easily grasp the part of the outer patch 2 overlapping the uncoated area 145.

[0122] When the outer patch 2 is peeled off from the tubular bag body 1, the outer patch 2 is peeled off first from the upper fold 113 and lastly from the lower fold 108. When viewed perpendicularly to the outer patch 2, the direction from the upper fold 113 toward the lower fold 108 is defined as the outer patch peeling direction D3.

[0123] The spot adhesive 144 is disposed in a portion adjacent to the uncoated area 145 on the outer surface 115 of the upper paper folding portion 112. Specifically, the spot adhesive 144 is disposed adjacent to the uncoated area 145 in the outer patch peeling direction D3. Since the uncoated area 145 is not attached to the outer patch 2, the outer patch 2 is easily peeled off from the portion adjacent to the uncoated area 145 on the outer surface 115 of the upper paper folding portion 112. However, since the spot adhesive 144 is disposed in a portion adjacent to the uncoated area 145 on the outer surface 115 of the upper paper folding portion 112, the outer patch 2 is less likely to peel off from the portion adjacent to the uncoated area 145 on the outer surface 115 of the upper paper folding portion 112.

[0124] Other configurations of the paper bag according to the eighth embodiment are the same as those of the paper bag according to the fifth embodiment.

[0125] As described above, the paper bag according to the eighth embodiment includes a tubular bag body 1 and an outer patch 2. The tubular bag body 1 includes a tubular portion 101 and an opening portion 102 that opens and closes an opening 103 of the tubular portion 101. The outer patch 2 is provided in the opening portion 102. The opening portion 102 includes a bottom paper 104 and an upper paper 105. The bottom paper 104 and the upper paper 105 are integrally provided in the tubular portion 101. The bottom paper 104 and the upper paper 105 overlap each other to close the opening 103 of the tubular portion 101. The bottom paper 104 includes a bottom paper base 106 and a bottom paper folding portion 107 provided in the bottom paper base 106. The upper paper 105 includes an upper paper base 111 and an upper paper folding portion 112 provided in the upper paper base 111. The inner surface 109 of the lower paper folding portion 107 is attached to the lower paper base 106 and the upper paper base 111 via an opening glue 117. The inner surface 114 of the upper paper folding portion 112 is attached to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper folding portion 107 via an opening glue 118 and an opening glue 119. The outer patch 2 is attached to the outer surface 115 of the upper paper base 111, the lower paper base 106, and the upper paper folding portion 112 via an opening glue 120 and an opening glue 136. The outer patch 2 is also attached to the outer surface 110 of the lower paper folding portion 107 via a fixing glue 138. The boundary line between the lower paper base 106 and the lower paper folding portion 107 is the lower paper fold 108. The boundary line between the upper paper base 111 and the upper paper folding portion 112 is the upper paper fold 113. The portion between the lower fold 108 and the upper fold 113 in the lower paper base 106 and the upper paper base 111, which is not overlapped with either the lower fold 107 or the upper fold 112, is the lower upper paper base exposed portion 127. The outer patch 2 is attached to a part of the lower upper paper base exposed portion 127 via a spot adhesive glue 143. This configuration can improve the strength of the attachment between the lower upper paper base exposed portion 127 and the outer patch 2. This can prevent the outer patch 2 from peeling off from the lower upper paper base exposed portion 127 when the paper bag is carried with contents stored inside the tube portion 101.

[0126] Furthermore, in the paper bag according to embodiment 8, the end of the outer patch 2 in the width direction D1 of the paper bag is attached to the portion of the lower paper upper paper base exposed portion 127 where the spot adhesive glue 143 is applied. With this configuration, it is possible to improve the strength of the attachment between the end of the outer patch 2 in the width direction D1 of the paper bag and the lower paper upper paper base exposed portion 127.

[0127] Furthermore, in the paper bag according to the eighth embodiment, an uncoated area 145 to which the outer patch 2 is not attached is formed on the outer surface 115 of the upper paper folding portion 112. The outer patch 2 is attached to a portion of the outer surface 115 of the upper paper folding portion 112 adjacent to the uncoated area 145 via a spot adhesive glue 144. This configuration makes it possible to prevent the outer patch 2 from peeling off from the portion of the outer surface 115 of the upper paper folding portion 112 adjacent to the uncoated area 145.

[0128] In the paper bag according to the eighth embodiment, the uncoated area 145 is disposed at the end of the outer surface 115 of the upper folded portion 112 on the side of the upper fold 113. With this configuration, the worker can easily grasp the portion of the outer patch 2 that overlaps the uncoated area 145.

[0129] The method for manufacturing a paper bag according to the eighth embodiment includes a lower paper and upper paper forming step, a lower paper and upper paper pasting step, and an outer patch pasting step. In the lower paper and upper paper forming step, the cylindrical body 3 is folded flat, and a cylindrical body fold 303 parallel to one opening end 301 is formed at a position a preset distance away from one opening end 301 of the folded cylindrical body 3 toward the other opening end 302. In the lower paper and upper paper forming step, both of a pair of corners 304 at one opening end 301 are folded inward of the cylindrical body 3 up to the cylindrical body fold 403 to form the lower paper 104 and the upper paper 105. In the lower paper and upper paper pasting step, a lower paper fold 108 parallel to the cylindrical body fold 303 is formed in the lower paper 104. In the lower paper and upper paper forming step, an upper paper fold 113 parallel to the cylindrical body fold 303 is formed in the upper paper 105. In the lower paper-upper paper bonding process, the inner surface 109 of the lower paper fold 107 is bonded to the lower paper base 106 and the upper paper base 111 via an opening glue 117. In the lower paper-upper paper bonding process, the inner surface 114 of the upper paper fold 112 is bonded to the outer surface 110 of the upper paper base 111, the lower paper base 106, and the lower paper fold 107 via an opening glue 118 and an opening glue 119. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 115 of the upper paper base 111, the lower paper base 106, and the upper paper fold 112 via an opening glue 120 and an opening glue 136. In the outer patch bonding process, the outer patch 2 is bonded to the outer surface 110 of the lower paper fold 107 via an adhesive glue 138. In the outer patch bonding process, the outer patch 2 is bonded to a portion of the lower paper upper paper base exposed portion 127 via spot adhesive glue 143. This configuration can improve the bonding strength between the lower paper upper paper base exposed portion 127 and the outer patch 2. This can prevent the outer patch 2 from peeling off from the lower paper upper paper base exposed portion 127 when the paper bag is carried with contents stored inside the tube portion 101.

[0130] Embodiment 9 FIG. 24 is a front view showing a main part of a paper bag according to the ninth embodiment. FIG. 24 shows a main part of the paper bag before the outer patch 2 is attached to the cylindrical bag body 1. An uncoated area 146 to which the outer patch 2 is not attached is formed on the outer surface 115 of the upper paper folding portion 112. The uncoated area 146 is disposed at a position away from the upper paper fold 113 on the outer surface 115 of the upper paper folding portion 112. Specifically, the uncoated area 146 is disposed away from the upper paper fold 113 in the outer patch peeling direction D3. Therefore, the opening glue 136 is applied between the uncoated area 146 and the upper paper fold 113.

[0131] An opening glue 136 is applied between the uncoated area 146 and the upper paper fold 113, thereby preventing foreign matter from entering the uncoated area 146. In order for an operator to grasp the portion of the outer patch 2 that is overlaid on the uncoated area 146, the operator peels off the outer patch 2 from the portion between the uncoated area 146 and the upper paper fold 113 on the outer surface 115 of the upper paper fold 112.

[0132] In the width direction D1 of the paper bag, the dimensions of uncoated area 146 in the paper bag according to embodiment 9 are larger than the dimensions of uncoated area 145 in the paper bag according to embodiment 8. This allows a worker to easily grasp the portion of outer patch 2 that overlaps uncoated area 146.

[0133] The spot adhesive 144 is disposed in a portion adjacent to the uncoated area 146 on the outer surface 115 of the upper paper folding portion 112. Specifically, the spot adhesive 144 is disposed adjacent to the uncoated area 146 in the outer patch peeling direction D3. Since the uncoated area 146 is not attached to the outer patch 2, the outer patch 2 is easily peeled off from the portion adjacent to the uncoated area 146 on the outer surface 115 of the upper paper folding portion 112. However, since the spot adhesive 144 is disposed in a portion adjacent to the uncoated area 146 on the outer surface 115 of the upper paper folding portion 112, the outer patch 2 is less likely to peel off from the portion adjacent to the uncoated area 146 on the outer surface 115 of the upper paper folding portion 112.

[0134] Other configurations of the paper bag according to the ninth embodiment are the same as those of the paper bag according to the eighth embodiment.

[0135] As described above, in the paper bag according to the ninth embodiment, the uncoated area 146 is disposed at a position away from the upper paper fold 113 on the outer surface 115 of the upper paper folding portion 112. With this configuration, it is possible to prevent foreign matter from entering the uncoated area 146.

[0136] In the paper bags according to the eighth and ninth embodiments, three spot-fixed glues 143 are arranged in each of the lower paper upper paper base exposed portions 127. However, this is not limited to the above. For example, as shown in FIG. 25, two spot-fixed glues 143 may be arranged in each of the lower paper upper paper base exposed portions 127. Also, as shown in FIG. 26, one spot-fixed glue 143 may be arranged in each of the lower paper upper paper base exposed portions 127. Also, as shown in FIG. 27, no spot-fixed glue 143 may be arranged in each of the lower paper upper paper base exposed portions 127.

[0137] In addition, in the paper bags according to the eighth and ninth embodiments, the configuration in which the spot-fixed glue 143 and the spot-fixed glue 144 are each shaped like a rectangle has been described. However, this is not limited to this. For example, as shown in FIG. 28, at least one of the spot-fixed glue 143 and the spot-fixed glue 144 may be shaped like a triangle. In this case, the triangular spot-fixed glue 143 and the spot-fixed glue 144 may be arranged so that the dimension in the width direction D1 of the paper bag increases toward the outer patch peeling direction D3. This makes it easier for the worker to peel off the outer patch 2. In addition, the spot-fixed glue 143 and the spot-fixed glue 144 are not limited to a triangle, and may be formed so long as the dimension in the width direction D1 of the paper bag increases toward the outer patch peeling direction D3. In addition, at least one of the spot-fixed glue 143 and the spot-fixed glue 144 may be formed like a circle.

[0138] Also, in the paper bags according to the eighth and ninth embodiments, a configuration has been described in which the opening glue 120 is uniformly applied to the lower paper upper paper base exposed portion 127. However, this is not limited to this. For example, as shown in FIG. 29, a configuration may be used in which multiple opening glues 120, each formed in a straight line and parallel to each other, are applied to the lower paper upper paper base exposed portion 127. Adjacent opening glues 120 are spaced apart from each other. In this case, the amount of opening glue 120 applied to the lower paper upper paper base exposed portion 127 can be reduced.

[0139] Also, in the paper bags according to the eighth and ninth embodiments, a configuration has been described in which the opening glue 121 is uniformly applied to the lower folded portion exposed portion 129. However, this is not limited to this. For example, as shown in FIG. 29, a configuration may be used in which multiple opening glues 121, each formed in a straight line and parallel to each other, are applied to the lower folded portion exposed portion 129. Adjacent opening glues 121 are spaced apart from each other. In this case, the amount of opening glue 121 applied to the lower folded portion exposed portion 129 can be reduced.

[0140] Also, in the paper bag according to the ninth embodiment, a configuration has been described in which the entire spot-bonded glue 144 is disposed away from the uncoated region 146 in the outer patch peeling direction D3. However, this is not limited to this. For example, the spot-bonded glue 144 may be disposed so that at least a portion of it is surrounded by the uncoated region 146. Even in this case, the spot-bonded glue 144 is disposed so as to be adjacent to the uncoated region 146 in the outer patch peeling direction D3.

[0141] In the paper bags according to the embodiments, a double bottomed paper bag has been described. However, a single bottomed paper bag may be used.

[0142] Although the paper bags and the manufacturing methods thereof according to the preferred embodiments have been described above, the paper bags and the manufacturing methods thereof according to the above-mentioned embodiments are not limited to the above-mentioned embodiments. Various modifications and alterations can be made to the paper bags and the manufacturing methods thereof according to the above-mentioned embodiments without departing from the scope of the claims. [Explanation of symbols]

[0143] 1 tubular bag body, 2 outer patch, 3 tubular body, 101 tubular portion, 102 opening portion, 103 opening, 104 bottom paper, 105 top paper, 106 bottom paper base, 107 bottom paper folded portion, 108 bottom paper crease, 109 inner surface, 110 outer surface, 111 top paper base, 112 top paper folded portion, 113 top paper crease, 114 inner surface, 115 outer surface, 116 triangular portion, 117 opening glue, 118 opening glue, 119 opening glue, 120 opening glue, 121 opening glue, 122 adhesive glue, 123 end, 124 end, 125 outer peripheral portion of folded portion of top paper, 126 opening glue, 127 exposed portion of bottom paper top paper base, 128 adhesive glue, 129 Exposed portion of lower folded portion, 130 fixed glue, 131 outer surface tip of upper folded portion, 132 fixed glue, 133 opening glue, 134 uncoated area, 135 fixed glue, 136 opening glue, 137 outer surface base end of lower folded portion, 138 fixed glue, 139 spot fixed glue, 140 spot fixed glue, 141 uncoated area, 142 uncoated area, 143 spot fixed glue, 144 spot fixed glue, 145 uncoated area, 146 uncoated area, 301 one opening end, 302 the other opening end, 303 fold of cylindrical body, 304 corner.

Claims

1. A cylindrical bag body having a cylindrical portion and an opening portion for opening and closing an opening of the cylindrical portion; An outer patch provided at the opening portion; Equipped with the opening portion has a lower sheet and an upper sheet that are integrally provided on the cylindrical portion and overlap each other to close the opening, The bottom sheet has a bottom sheet base and a bottom sheet folding section provided on the bottom sheet base, The upper paper has an upper paper base and an upper paper folding portion provided on the upper paper base, The inner surface of the lower folded portion is bonded to the lower base and the upper base via an opening glue, The inner surface of the upper folding portion is bonded to the outer surfaces of the upper base, the lower base and the lower folding portion via an opening glue; The outer patch is attached to the outer surfaces of the upper paper base, the lower paper base and the lower paper fold via an opening glue, and is attached to the outer surface of the upper paper fold via a fixing glue; A boundary line between the bottom paper base and the bottom paper fold is a bottom paper fold line; A boundary line between the upper paper base and the upper paper fold is defined as an upper paper fold line; a portion of the lower paper base and the upper paper base between the lower paper fold and the upper paper fold, the portion not overlapping either the lower paper fold or the upper paper fold, being an exposed portion of the lower paper upper paper base; The paper bag has the outer patch attached to a portion of the exposed portion of the upper base of the lower paper via a spot adhesive.

2. 2. The paper bag according to claim 1, wherein an end of the outer patch in the width direction of the paper bag is affixed to the portion of the exposed portion of the lower paper and upper paper base where spot adhesive glue is applied.

3. A portion of the outer surface of the lower folding portion where the upper folding portion is not overlapped is defined as an exposed portion of the lower folding portion, a non-coated area where the outer patch is not attached is formed in the exposed portion of the lower folded portion; 3. The paper bag according to claim 1, wherein the outer patch is attached to a portion of the exposed lower folded portion adjacent to the uncoated region via a spot adhesive.

4. The paper bag according to claim 3 , wherein the uncoated area is disposed at an end of the exposed portion of the lower folded portion on the side of the lower fold.

5. The paper bag according to claim 3 , wherein the uncoated area is disposed at a position away from the lower fold in the exposed portion of the lower fold.

6. A cylindrical bag body having a cylindrical portion and an opening portion for opening and closing an opening of the cylindrical portion; An outer patch provided at the opening portion; Equipped with the opening portion has a lower sheet and an upper sheet that are integrally provided on the cylindrical portion and overlap each other to close the opening, The bottom sheet has a bottom sheet base and a bottom sheet folding section provided on the bottom sheet base, The upper paper has an upper paper base and an upper paper folding portion provided on the upper paper base, The inner surface of the lower folded portion is bonded to the lower base and the upper base via an opening glue, The inner surface of the upper folding portion is bonded to the outer surfaces of the upper base, the lower base and the lower folding portion via an opening glue; The outer patch is attached to the outer surfaces of the upper paper base, the lower paper base and the upper paper fold via an opening glue, and is attached to the outer surface of the lower paper fold via a fixing glue; A boundary line between the bottom paper base and the bottom paper fold is a bottom paper fold line; A boundary line between the upper paper base and the upper paper fold is defined as an upper paper fold line; a portion between the lower fold and the upper fold in the lower base and the upper base, the portion not overlapping either the lower fold or the upper fold, being an exposed portion of the lower and upper base; The paper bag has the outer patch attached to a portion of the exposed portion of the upper base of the lower paper via a spot adhesive.

7. The paper bag according to claim 6, wherein an end portion of the outer patch in the width direction of the paper bag is affixed to the portion of the exposed portion of the upper base of the lower paper where the spot adhesive glue is applied.

8. An uncoated area where the outer patch is not attached is formed on the outer surface of the upper folded portion, The paper bag according to claim 6 or claim 7, wherein the outer patch is attached to a portion of the outer surface of the upper folded portion adjacent to the uncoated area via a spot adhesive.

9. The paper bag according to claim 8 , wherein the uncoated area is disposed at an end of the outer surface of the upper folded portion on the side of the upper fold.

10. The paper bag according to claim 8 , wherein the uncoated area is disposed at a position away from the upper fold on the outer surface of the upper fold. Paper bag.

11. A method for producing a paper bag according to claim 1 or 2, a lower paper / upper paper forming process for forming the lower paper and the upper paper by folding a tubular body flat, forming a tubular body crease parallel to one open end of the folded tubular body at a position a preset distance away from one open end toward the other open end, and folding both of a pair of corners at one open end into the inside of the tubular body up to the tubular body crease, a lower paper-upper paper bonding process, which includes forming a lower paper fold parallel to the fold of the cylindrical body in the lower paper, forming an upper paper fold parallel to the fold of the cylindrical body in the upper paper, bonding the inner surface of the lower paper fold to the lower paper base and the upper paper base via an opening glue, and bonding the inner surface of the upper paper fold to the outer surface of the upper paper base, the lower paper base, and the lower paper fold via an opening glue; an outer patch pasting process for pasting the outer patch on the outer surfaces of the upper paper base, the lower paper base, and the lower paper fold using an opening glue, and pasting the outer patch on the outer surface of the upper paper fold using a fixing glue; Equipped with In the outer patch attaching step, the outer patch is attached to a portion of the exposed portion of the upper paper base of the lower paper via a spot adhesive.

12. A method for producing a paper bag according to claim 6 or claim 7, a lower paper / upper paper forming process for forming the lower paper and the upper paper by folding a tubular body flat, forming a tubular body crease parallel to one open end of the folded tubular body at a position a preset distance away from one open end toward the other open end, and folding both of a pair of corners at one open end into the inside of the tubular body up to the tubular body crease, a lower paper-upper paper bonding process, which includes forming a lower paper fold parallel to the fold of the cylindrical body in the lower paper, forming an upper paper fold parallel to the fold of the cylindrical body in the upper paper, bonding the inner surface of the lower paper fold to the lower paper base and the upper paper base via an opening glue, and bonding the inner surface of the upper paper fold to the outer surface of the upper paper base, the lower paper base, and the lower paper fold via an opening glue; an outer patch pasting process for pasting the outer patch on the outer surfaces of the upper paper base, the lower paper base and the upper paper fold using an opening glue, and pasting the outer patch on the outer surface of the lower paper fold using a fixing glue; Equipped with In the outer patch attaching step, the outer patch is attached to a portion of the exposed portion of the upper paper base of the lower paper via a spot adhesive.

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