Packaging bag

Abstract

An envelope-type non-gusseted packaging bag (1) in which a top surface part (3) and a bottom surface part (2) extending along both the X direction and the Y direction are overlaid to each other in the Z direction orthogonal to the X direction and the Y direction without having a gusset interposed therebetween comprises: a stretchable cushioning part (4) which is provided only to at least a portion of the top surface part (3) excluding the central portion thereof in the Y direction, and in which a plurality of slits (4a) are provided in a staggered pattern; and a non-cushioning part (5) which is not provided with any slits (4a) and cannot be stretched. The non-cushioning part (5) has a top surface non-cushioning section (7) provided in a portion of the top surface part (3) other than a region where the cushioning part (4) is provided, and a bottom surface non-cushioning section (6) provided throughout the bottom surface part (2).

Description

packaging bag

[0001] The present invention relates to an envelope-type packaging bag without a gusset.

[0002] Conventionally, envelopes without gussets for containing flat contents are known, and gusseted envelopes for containing three-dimensional contents are also known. Gusseted envelopes are pre-folded to create a gusset between the front and back surfaces. When a gusseted envelope is unused, it has a mountain fold line on the front side, a mountain fold line on the back side, and a valley fold line between these two pairs of mountain fold lines, and these three fold lines are folded on the left and right sides. By folding these three fold lines, not only are the front and back surfaces overlapping, but also the planar region between the mountain fold line and the valley fold line on the front side (the front half of the gusset) and the planar region between the mountain fold line and the valley fold line on the back side (the back half of the gusset), a total of four surfaces, overlapping.

[0003] In contrast to the gusseted envelope, which is folded back along six fold lines, the front and back of an envelope, whether unused or used, are folded back along a pair of mountain fold lines, and only the front and back are folded back along two fold lines, overlapping each other. Therefore, although a gusseted envelope can accommodate more three-dimensional contents than a non-gusseted envelope, a non-gusseted envelope is less bulky than a gusseted envelope.

[0004] In response to this, a gussetless, cylindrical package has been proposed that ensures sufficient storage capacity for the contents while being less bulky when unused. The proposed package comprises a first sheet corresponding to either the front or back side and a second sheet corresponding to the other of the front or back sides, which are bonded together at their left and right side edges, and staggered cuts are provided in each of the first and second sheets along the entire longitudinal direction (i.e., the up-down direction) perpendicular to the left-right direction, except for the left and right side edges. When fruit is placed in this package through an opening provided at the longitudinal edge, the cuts open and the package deforms to conform to the contour of the fruit (see Patent Document 1).

[0005] Japanese Patent Publication No. 2022-173847

[0006] However, as described above, packaging bags with staggered cuts on both the front and back surfaces are difficult to stand upright when placed on the front or back surface because the cuts deform on both the front and back surfaces when contents such as fruit are placed inside. Furthermore, because the cuts are provided on the entire front or back surface except for the left and right side edges, the area where the cuts open and deform is wide, which can lead to excessive stretching of the cuts in some areas, which can cause breakage.

[0007] For users of packaging bags that are difficult to stand on their own stably or that are prone to breakage, it is difficult to place the packaging bag stably, which may result in damage and leakage of the contents. This may reduce the usability of the packaging bag. Therefore, there is room for improvement in ensuring the usability of packaging bags.

[0008] The present invention was conceived in consideration of the above-mentioned problems, and one of its objectives is to ensure the usability of a gusset-less envelope-type packaging bag. However, other objectives of the present invention are not limited to this objective. The effects and advantages derived from the configurations shown in the "Mode for Carrying Out the Invention" described below, which cannot be obtained with conventional technology, can also be considered as other objectives of the present invention.

[0009] The packaging bag disclosed herein has the following configurations (1) to (10): (1) A gussetless envelope-type packaging bag in which top and bottom surfaces extending along both a first direction and a second direction perpendicular to the first direction are overlapped with each other in a thickness direction perpendicular to the first and second directions without a gusset therebetween, the packaging bag comprising: a stretchable buffer section provided in at least a portion of the top surface except for a central portion in the first direction, the stretchable buffer section having a plurality of slits arranged in a staggered pattern; and a non-buffering section that does not have the slits and is non-stretchable, the non-buffering section comprising a top non-buffering section provided in a portion of the top surface except for the area where the buffering section is provided, and a bottom non-buffering section provided over the entire bottom surface.

[0010] (2) The packaging bag described in (1), characterized in that the top surface non-buffering portion extends along a predetermined direction in a plane along both the first direction and the second direction, and the buffering portion has the plurality of slits extending along the predetermined direction arranged in a staggered pattern.

[0011] (3) The packaging bag according to (1) or (2), characterized in that the top surface non-cushioning portion has an edge non-cushioning portion provided in an area including an edge in the first direction. (4) The packaging bag according to (3), characterized in that the edge non-cushioning portion is provided in a tapered area in which the dimension in the first direction increases toward the outside in the second direction.

[0012] (5) The packaging bag according to any one of (1) to (4), characterized in that the buffer sections are disposed on both sides of the central section in the first direction. (6) The packaging bag according to any one of (1) to (5), characterized in that the top surface non-buffering section is provided in the central section and has a center section with a hand hole drilled therein.

[0013] (7) A packaging bag according to any one of (1) to (6), characterized in that the top surface portion and the bottom surface portion each have an opening surrounded by one edge that is one edge in any direction in a plane along which both the first direction and the second direction are aligned, and the bag has a tongue that extends from either the top surface portion or the bottom surface portion and is attached to the other of the top surface portion or the bottom surface portion.

[0014] (8) The packaging bag according to (7), characterized in that the tongue extends from a part of the one edge of either the top surface portion or the bottom surface portion. (9) The packaging bag according to (7) or (8), characterized in that the tongue has a fold line extending along the second direction at the center in the first direction. (10) The packaging bag according to any one of (1) to (9), characterized in that the packaging bag is made of kraft paper.

[0015] According to this invention, the usability of the packaging bag can be ensured.

[0016] 3 is a plan view showing the state of the packaging bag according to the embodiment when it is unused. FIG. 4 is a plan view showing an enlarged view of a main part of the buffer section in an unstretched state. FIG. 5 is a perspective view showing an enlarged view of a main part of the buffer section in an stretched state. FIG. 6 is a cross-sectional view showing the A-A cross section of FIG. 3. FIG. 7 is a perspective view showing the state of the packaging bag according to the embodiment when contents are contained therein (first state when in use). FIG. 8 is a perspective view showing the state of the packaging bag according to the embodiment after contents have been contained therein (second state when in use).

[0017] A packaging bag according to an embodiment will be described below. The packaging bag of this embodiment is an envelope-type bag without a gusset. This packaging bag has a flat shape when it is unused and before contents are placed inside (also referred to as "unused"), and when it is used and after contents are placed inside (also referred to as "in use"), it expands and deforms to conform to the outer shape of the contents, thereby taking on a three-dimensional shape.

[0018] In this embodiment, a paper packaging bag (so-called "paper bag") made of paper is exemplified. Such paper packaging bags can be formed from paper materials such as kraft paper, fine paper, medium-quality paper, art paper, coated paper, cast-coated paper, inkjet recording paper, Clupak paper, liner paper, and white paperboard. They can also be formed from laminated paper, in which a thermoplastic resin such as polyethylene resin is laminated on one or both sides of such paper or paperboard; nonwoven fabrics such as spunbond and spunlace; plastic sheets such as synthetic paper and film; and paper materials such as laminated paper and corrugated cardboard. Among these, paper and paperboard are suitable for use as sheet materials for forming packaging bags because they are easy to recycle from waste paper. Kraft paper, Clupak paper, and paperboard are particularly suitable for use as sheet materials for forming packaging bags because of their excellent strength. The sheet materials for forming packaging bags may have a coating layer on one or both sides for the purposes of imparting water resistance, printability, and improving strength.

[0019] In the following embodiments, a Cartesian coordinate system having three mutually orthogonal coordinate axes, the X-axis, the Y-axis, and the Z-axis, is used as the reference for directions in the description. In this Cartesian coordinate system, the direction along the X-axis is referred to as the "X-direction" (second direction), the direction along the Y-axis is referred to as the "Y-direction" (first direction), and the direction along the Z-axis is referred to as the "Z-direction" (direction perpendicular to the thickness direction, the first direction, and the second direction). Furthermore, a plane along both the X-direction and the Y-direction is referred to as the "XY plane" (a plane along which both the first direction and the second direction are aligned), and a plane along both the Y-direction and the Z-direction is referred to as the "YZ plane." Additionally, a view from the Z-direction is referred to as a "Z-direction view" (planar view).

[0020] The X direction has two inherent directions: the direction from negative to positive on the X axis and the direction from positive to negative on the X axis, which are opposite to each other. Therefore, one of the X directions is referred to as the "X1 direction," and the other as the "X2 direction." Similarly, one of the Y directions is referred to as the "Y1 direction" (one side), and the other as the "Y2 direction" (the other side). One of the Z directions is referred to as the "Z1 direction," and the other as the "Z2 direction."

[0021] In this embodiment, the expressions "along", "extend along", and "extend along" are not limited to directions parallel to a reference direction or plane, but also include directions inclined at an angle of less than 45°, such as 5° or 10°, relative to the reference direction or plane. The packaging bag of this embodiment may be arranged asymmetrically at least in the Z direction, and all or at least some of the components may be arranged symmetrically in the X direction or the Y direction, or all or at least some of the components may be arranged asymmetrically in the X direction or the Y direction.

[0022] [I. One Embodiment] In the following embodiment, the configuration of the packaging bag will be described in item [1], and the action and effect of the configuration of item [1] will be described in item [2]. [1. Configuration] First, referring to FIG. 1, which is a plan view seen from the Z1 direction, an unused packaging bag 1 will be described. In FIG. 1, the X direction corresponds to the left-right direction of the paper as shown, the Y direction corresponds to the up-down direction of the paper as shown, and the Z direction corresponds to the direction connecting the front and back of the paper, although not shown. FIG. 1 illustrates a packaging bag 1 whose dimension in the Y direction is longer than its dimension in the X direction.

[0023] The X direction may be referred to as the short direction or width direction. The Y direction may be referred to as the long direction or the direction in which contents are inserted or removed. The Z direction may be referred to as the thickness direction or depth direction. Furthermore, of the X directions, the X1 direction may be referred to as the left, and the X2 direction may be referred to as the right. Of the Y directions, the Y1 direction may be referred to as the direction in which contents are removed or the upward direction when inserting or removing contents, and the Y2 direction may be referred to as the direction in which contents are stored or the downward direction when inserting or removing contents. Of the Z directions, the Z1 direction side may be referred to as the front side or front side, and the Z2 direction side may be referred to as the back side or rear side.

[0024] When unused, the packaging bag 1 has the bottom surface 2 and the top surface 3 overlapped in the Z direction without a gusset in between. The bottom surface 2 is located on the Z2 side of the packaging bag 1. The top surface 3 is located on the Z1 side of the packaging bag 1. The bottom surface 2 and the top surface 3 have the same dimensions in the X direction and the Y direction, and are formed in sheet shapes of the same size when viewed in the Z direction.

[0025] An opening 9, through which the contents are inserted and removed, is provided on the Y1 side of the packaging bag 1. The opening 9 is surrounded by one edge 2a, which is the edge on the Y1 side of the bottom surface 2, and one edge 3a, which is the edge on the Y1 side of the top surface 3. However, the opening 9 is not limited to being arranged so as to be surrounded by one edge 2a, 3a on the Y1 side of the bottom surface 2 and the top surface 3, but may be provided at a position so as to be surrounded by one edge, which is one edge in any direction in the XY plane, of each of the bottom surface 2 and the top surface 3.

[0026] The packaging bag 1 illustrated here is provided with a tongue 8 for opening and closing the opening 9. Here, the example shows the tongue 8 extending from one edge 3a of the top surface 3 (either the edge of the top surface or the bottom surface). As illustrated by the solid line in Fig. 1 , when the tongue 8 is deployed in the Y1 direction from the one edge 3a of the top surface 3, the opening 9 is open. On the other hand, when the tongue 8 is folded back in the Y2 direction at the one edge 3a of the top surface 3 (not shown), the opening 9 is closed. The tongue 8 that closes the opening 9 is bonded to the bottom surface 2 (the other of the top surface and the bottom surface).

[0027] Alternatively, as shown by the two-dot chain line in Fig. 1, the tongue 8' may be provided extending from only a portion of one edge 3a of the top surface 3. In other words, the tongue 8' does not extend from the entire region (entirety) of one edge 3a of the top surface 3, but does not extend from any portion of this one edge 3a except for a portion. The tongue 8' illustrated by the two-dot chain line in Fig. 1 does not extend from the end sides in the X1 direction and X2 direction (i.e., the outer sides in the X direction), but extends only from the central portion in the X direction.

[0028] Furthermore, a crease 8C' extending along the X direction is provided at the center of the tongue piece 8' in the Y direction, as illustrated by the two-dot chain line in Fig. 1. Half of the tongue piece 8' in the Y1 direction is folded back at the crease 8C' and attached to the bottom surface portion 2, thereby closing a portion of the opening 9 with the tongue piece 8'. This crease 8C' can also be considered a fold line, which is formed by offsetting the point where the tongue piece 8 is folded back (i.e., one edge 3a of the top surface portion 3), shown by the solid line in Fig. 1, in the Y1 direction. In other words, the crease 8C' along which the tongue piece 8' is folded back is offset in the Y1 direction with respect to one edge 3a of the top surface portion 3.

[0029] The tongue pieces 8, 8' are not limited to extending from one edge 3a of the top surface 3, but may extend from one edge 2a of the bottom surface 2 (either the edge of the top surface or the bottom surface). In this case, the tongue pieces 8, 8' that close the opening 9 are bonded to the top surface 3 (the other of the top surface and the bottom surface). Alternatively, the tongue piece 8 shown by the solid line in FIG. 1 is not limited to being folded back at one edge 3a of the top surface 3, but may have a crease 8C (shown by a dashed line in FIG. 1) extending along the X direction at the center of the tongue piece 8 in the Y direction. In this case, the opening 9 is closed by folding back half of the tongue piece 8 at the crease 8C.

[0030] The bottom surface portion 2 and the top surface portion 3 are connected to each other at their edges except for edges 2a, 3a in the Y1 direction. The rectangular bottom surface portion 2 and top surface portion 3 shown in Figure 1 have edges 2a, 3a in the Y1 direction corresponding to one of the four sides of the rectangle, so the bottom surface portion 2 and the top surface portion 3 are connected to each other at the remaining three sides. The packaging bag 1 having the above-mentioned basic configuration is provided with a stretchable buffer portion 4 and a non-stretchable non-buffer portion 5, which will be described next.

[0031] Non-buffering sections 5 are provided on the bottom surface 2 and top surface 3 of the packaging bag 1 in areas excluding the areas where the buffering sections 4 are provided. In other words, the buffering sections 4 are provided on the bottom surface 2 and top surface 3 in areas excluding the areas where the non-buffering sections 5 are provided. The buffering sections 4 are provided only on at least a portion of the top surface 3 excluding the central portion in the Y direction. Here, an example is shown in which the buffering sections 4 are provided on both sides in the Y direction (both on one side and on the other side in the first direction) of the central portion in the Y direction on the top surface 3.

[0032] ==Buffer Section== The buffer section 4 is an extensible section with multiple notches 4a (only two are marked with reference numerals in FIG. 1). The notches 4a in the buffer section 4 are arranged in a staggered pattern, similar to the notches in cushioning paper materials such as cushion paper and honey paper. The notches 4a are sections cut into a portion of the top surface section 3 in the Z direction, and may also be called slits or cuts.

[0033] The buffer section 4 is provided with a plurality of staggered notches 4a, making it stretchable. When the contents are placed in the packaging bag 1 through the opening 9, the buffer section 4 stretches (deforms) to conform to the outer shape of the contents. That is, before the contents are placed in the packaging bag 1 (i.e., when the packaging bag 1 is unused), the buffer section 4 is in an unstretched state (hereinafter referred to as an "unstretched state"), and after the contents are placed in the packaging bag 1 (i.e., when the packaging bag 1 is used), the buffer section 4 is in an stretched state (hereinafter referred to as an "stretched state").

[0034] Each of the slits 4a that allow the buffer section 4 to be stretched in this manner extends along a predetermined direction, as shown in Fig. 2. In this embodiment, the "predetermined direction" is illustrated as being along the X direction, and an example is given in which the slits 4a extend along the X direction. However, the predetermined direction may be any direction that intersects at least the Y direction in the XY plane, and each of the slits 4a may be cut along a direction that intersects the Y direction in the XY plane.

[0035] The notches 4a are arranged intermittently along the X direction. That is, between adjacent notches 4a in the X direction, there are provided non-notched portions 4b. The X-direction dimension of the notches 4a is set larger than the X-direction dimension of the non-notched portions 4b. That is, if the dimension of the notches 4a is "L1" and the dimension of the non-notched portions 4b is "L2," then inequality 1 "L1 > L2" is satisfied.

[0036] Here, a first pattern P1 is defined as one row in which the notched portions 4a and the non-notched portions 4b are arranged alternately along the X direction. A second pattern P2 is defined as another row in which the notched portions 4a' and the non-notched portions 4b' are arranged alternately along the X direction and are shifted by half a pitch from the notched portions 4a and the non-notched portions 4b of the first pattern P1. The first pattern P1 and the second pattern P2 are arranged alternately along the Y direction.

[0037] Specifically, the X-direction center C of the notch 4a in the first pattern P1 a and the X-direction center C of the non-cut portion 4b' in the second pattern P2b Similarly, the width direction center C of the non-cut portion 4b of the first pattern P1 is b and the width direction center C of the notch 4a' in the second pattern P2 a The cut portions 4a, 4a' and the non-cut portions 4b, 4b' are arranged side by side in the Y direction. The buffer portion 4 having such cut portions 4a, 4a' and non-cut portions 4b, 4b' is manufactured by cutting an uncut sheet material while rotating it using a rotary die cutter having blades (cutter) on its outer periphery that correspond to the cut portions 4a, 4a'. Alternatively, the buffer portion 4 is manufactured by cutting an uncut sheet material while pressing it using a flat die cutter having blades that correspond to the cut portions 4a, 4a'.

[0038] The sheet pieces in the Y1 direction (upward in FIG. 2 ) relative to the notch 4a of the first pattern P1 are roughly divided into a first piece 41, a second piece 42, and a third piece 43 based on their positions relative to the notch 4a' and non-notch 4b' of the second pattern P2. The first piece 41 is the portion sandwiched between the X1-direction (leftward in FIG. 2 ) side of the notch 4a of the first pattern P1 and the X2-direction (rightward in FIG. 2 ) side of the notch 4a' of the second pattern P2. The second piece 42 is the portion sandwiched between the X-direction center of the notch 4a of the first pattern P1 and the non-notch 4b' of the second pattern P2. The third piece 43 is the portion sandwiched between the X2-direction side of the notch 4a of the first pattern P1 and the X1-direction side of the notch 4a' of the second pattern P2.

[0039] Similarly to the segments 41, 42, and 43, the sheet pieces in the Y2 direction relative to the notch 4a of the first pattern P1 are broadly divided into a fourth segment 44, a fifth segment 45, and a sixth segment 46. The fourth segment 44 is sandwiched between the X1-direction portion of the notch 4a of the first pattern P1 and the X2-direction portion of the notch 4a' of the second pattern P2. The fifth segment 45 is sandwiched between the X-direction center portion of the notch 4a of the first pattern P1 and the non-notch portion 4b' of the second pattern P2. The sixth segment 46 is sandwiched between the X2-direction portion of the notch 4a of the first pattern P1 and the X1-direction portion of the notch 4a' of the second pattern P2.

[0040] Next, the buffer section 4 in a stretched state will be described with reference to Figure 3. While the buffer section 4 in an unstretched state (see Figure 2) extends planarly along the XY plane, the buffer section 4 in a stretched state stretches away from this XY plane. In the stretched buffer section 4, the pieces 41 to 46 (see Figures 3 and 4) rise in the Z direction, and the raised pieces 41 to 46 form a three-dimensional buffer cell 40. In other words, one buffer cell 40 appears when the pieces 41 to 46 arranged around one slit 4a rise up.

[0041] 3 , a first wall portion 51 corresponding to the first arm 41, a second wall portion 52 corresponding to the second arm 42, a third wall portion 53 corresponding to the third arm 43, a fourth wall portion 54 corresponding to the fourth arm 44, a fifth wall portion 55 corresponding to the fifth arm 45, and a sixth wall portion 56 corresponding to the sixth arm 46 are erected in the buffer cell 40 to form each side wall of the hexagonal tube. Note that, in a state where the buffer unit 4 is geometrically stretched to the maximum extent in the Y direction without being damaged (hereinafter referred to as the "maximum stretched state"), the first wall portion 51 and the fourth wall portion 54 are aligned along the same plane along the YZ plane, and the third wall portion 53 and the sixth wall portion 56 are aligned along another same plane along the YZ plane, with the second wall portion 52 and the fifth wall portion 55 facing each other in the Y direction. Therefore, in the buffer cell 40 in the maximum stretched state, the walls 51 to 56 are erected to form each side wall of the rectangular tube.

[0042] As described above, the cushioning section 4 after stretching is thicker than the sheet-like cushioning section 4 before stretching (so to speak, a "mat-like" or three-dimensional shape). The cushioning section 4, which has a certain thickness dimension, has a deformation margin for cushioning, i.e., a buffer margin. In this way, the shape of the cushioning section 4, which has been stretched from an unstretched state to a stretched state, changes from a sheet-like shape to a mat-like shape as a result of stretching, and the slits 4a each open into a mesh-like shape. Basically, the cushioning section 4 that has changed from a sheet-like shape to a mat-like shape will not return to a sheet-like shape; instead, the shape of the cushioning section 4 changes irreversibly with only a slight restoration due to restoring force.

[0043] Depending on the region of the packaging bag 1 where the buffer section 4 is stretchable as described above, it may be difficult for the packaging bag 1 to stand stably, and the buffer section 4 may be excessively stretched or the stress that stretches the buffer section 4 may be concentrated in a certain area, which may result in tearing (breakage) of the buffer section 4. Specifically, if a buffer section is provided on the bottom section of the packaging bag 1 in a state where the bottom section 2 is placed, this may cause the packaging bag to be unable to stand stably. Furthermore, if a buffer section is provided over the entire Y-direction area of ​​the top section, this may cause the buffer section to be excessively stretched or stress may be concentrated in the center section or edge sections of the top section in the Y-direction, which may result in tearing of the buffer section.

[0044] To elaborate, the wider the area in which the buffer section 4 is provided, the more likely it is to be damaged, but the more likely it is to be stretched in accordance with the general shape of the contents, which improves storage capacity. Therefore, in the packaging bag 1 of this embodiment shown in Fig. 1, the area of ​​the buffer section 4 is set to ensure an area for the buffer section 4 that stretches in accordance with the general shape of the contents while suppressing damage to the buffer section 4. Specifically, the buffer section 4 is provided over as wide an area as possible in areas of the packaging bag 1 that are less likely to be damaged by the slits 4a. On the other hand, in areas of the packaging bag 1 that are more likely to be damaged by the slits 4a, no buffer section 4 is provided, and a non-buffer section 5, which will be described next, is provided.

[0045] ==Non-Buffering Section== The non-buffering section 5 is a non-stretchable section that does not have the notch 4a that is provided in the buffering section 4. This non-buffering section 5 includes a bottom non-buffering section 6 provided over the entire bottom section 2, and a top non-buffering section 7 provided in an area (other section) of the top section 3 excluding the section (area) where the buffering section 4 is provided.

[0046] The bottom non-buffering portion 6 can be described as an inextensible bottom portion 2 that does not have the notch portion 4a. The top non-buffering portion 7 is provided in an area where, if buffering portions were provided over the entire top surface, stress that stretches the buffering portion would be concentrated in some areas or the buffering portion would be overstretched. Like the notch portion 4a, the top non-buffering portion 7 extends along a predetermined direction in the XY plane. That is, both the top non-buffering portion 7 and the notch portion 4a extend along a predetermined direction (here, the X direction).

[0047] The illustrated top surface non-buffering portion 7 includes a center portion 7C provided in the center portion in the Y direction and an edge non-buffering portion 7E provided in an area including one edge 3a of the top surface 3 (the edge in the Y direction of the packaging bag 1). The center portion in the Y direction of the top surface 3 where the center portion 7C is provided is an area where the buffering portion may stretch excessively if buffering portions were provided in an area including not only both sides of the center portion in the Y direction but also the center portion in the Y direction (in other words, almost the entire area of ​​the top surface in the Y direction). A hand hole 7H is formed in the illustrated center portion 7C to allow a user of the packaging bag 1 to place their fingers through.

[0048] Furthermore, the region of the top surface 3 including the Y-direction edge where the non-buffering edge portions 7E are provided can be considered to be a region where stress that stretches the buffering portion 4 is partially concentrated. The non-buffering edge portions 7E are provided in a tapered region whose Y-direction dimension increases as they extend outward in the X-direction. The "tapered region" referred to here can also be considered a region in which the X-direction dimension and Y-direction dimension increase as they approach the four corners of the top surface 3, at the X-direction end and Y-direction end, in order to space the buffering portion 4 away from these four corners, where stress is likely to concentrate. In other words, the non-buffering edge portions 7E are provided in a "tapered region" that aims to distribute stress that may be applied when contents are placed inside.

[0049] The edge non-buffering portions 7E illustrated here are provided in both an area including one edge 3a of the top surface 3 and an area including the other edge 3b, which is the edge on the Y2 direction side of the top surface 3. Therefore, on the top surface 3, from the Y1 direction to the Y2 direction, the edge non-buffering portion 7E provided in the area including one edge 3a of the top surface 3, the buffering portion 4 provided on the Y1 direction side of the central portion of the top surface 3 in the Y direction, the center portion 7C, the buffering portion 4 provided on the Y2 direction side of the central portion of the top surface 3 in the Y direction, and the edge non-buffering portion 7E provided in the area including the other edge 3b of the top surface 3 are arranged in this order.

[0050] Finally, the configuration of the packaging bag 1 will be described first, followed by a description of the packaging bag 1 after the contents have been placed inside. When the contents are placed inside the packaging bag 1, the opening 9 faces upward (i.e., the "standing position"), as shown in Fig. 5. That is, the contents are placed inside the packaging bag 1 through the opening 9 with the Y1 direction facing upward.

[0051] When contents are placed in the packaging bag 1, the buffer section 4 stretches and deforms to conform to the contours of the contents, separating the top section 3 from the bottom section 2. The non-buffer section 5 of the packaging bag 1 containing the contents does not stretch, but does deform slightly in accordance with the contours of the contents. For example, as shown in Fig. 6, the packaging bag 1, in which contents (shown dotted in Fig. 6) are placed and the opening 9 (see Fig. 5) is closed by the tongue 8 (see Fig. 5), is placed with the bottom section 2 and the top section 3 facing upward (i.e., "lying position"). That is, the packaging bag 1 in this position, in which the Z1 direction is upward, is used for storage, display, exhibition, sale, transport, and the like.

[0052] [2. Actions and Effects] The packaging bag 1 of this embodiment has the above-described configuration, and therefore can achieve the following actions and effects. (1) When contents are placed in the packaging bag 1, the buffer section 4 expands to conform to the outline of the contents, and three-dimensional honeycomb-shaped buffer cells 40 appear. At least a portion of the contents is enclosed by the buffer section 4 in this expanded state, and the three-dimensional buffer cells 40 absorb impacts on the contents.

[0053] On the other hand, the non-cushioning portion 5 having the bottom non-cushioning portion 6 and the top non-cushioning portion 7 does not have the slits 4a and is therefore non-stretchable. Therefore, when contents are placed in the packaging bag 1, the bottom non-cushioning portion 6 and the top non-cushioning portion 7 do not stretch, and only the buffering portion 4 provided on at least a portion of the top portion 3 excluding the central portion stretches. Therefore, when the packaging bag 1 is used with the bottom portion 2 placed on top, deformation is suppressed across the entire bottom portion 2, where the non-stretchable bottom non-cushioning portion 6 is provided, allowing the packaging bag 1 to stand stably. Furthermore, because the buffering portion 4 is provided only on at least a portion of the top portion 3 excluding the central portion, the stretchable region is limited to at least a portion of the top portion 3 excluding the central portion. Therefore, compared to a structure in which the slits 4a are provided in a staggered pattern across the entire top portion 3, tearing due to excessive stretching of the slits 4a can be suppressed. That is, by partially limiting the region of the top surface 3 that can be stretched by the slits 4a using the top surface non-buffering sections 7, excessive stretching of the buffering sections 4 can be suppressed, which helps to suppress breakage of the buffering sections 4. In this manner, the usability of the packaging bag 1 can be ensured by improving the self-standing stability of the packaging bag 1 and suppressing breakage of the slits 4a.

[0054] (2) Because the top non-cushioning portion 7 and the slits 4a both extend in a predetermined direction (here, the X direction), the top non-cushioning portion 7 can be easily separated from the bottom portion 2. In this case, the buffering portion 4 easily stretches in the Y direction, and when contents are placed in the packaging bag 1, the top non-cushioning portion 7, which is located in the central portion of the top portion 3, can be easily separated from the bottom portion 2. If the slits of the buffering portion were structured to extend in the Y direction, the buffering portion would easily stretch in the X direction. For this reason, a structure with slits extending in the Y direction may make it difficult to separate the central portion of the top portion from the bottom portion. In contrast, because the top non-cushioning portion 7 and the slits 4a extend in a predetermined direction in the packaging bag 1, the top non-cushioning portion 7, which is located in the central portion of the top portion 3, can be easily separated from the bottom portion 2, making it easier to unfold the packaging bag 1 and improving the capacity to accommodate thick, three-dimensional contents.

[0055] (3) In a structure in which the notch of the buffer section extends to the edge in the Y direction of the top surface, when the contents are placed in the packaging bag, the force that stretches the notch is concentrated on the edge in the Y direction or its vicinity, which may result in damage to the edge in the Y direction of the top surface or the notch provided in its vicinity. In contrast, by providing an edge non-buffering section 7E in an area including one edge 3a and the other edge 3b in the Y direction of the top surface 3, it is possible to prevent damage to the notch 4a of the buffer section 4 on the top surface 3.

[0056] (4) Furthermore, when contents are placed in the packaging bag 1, the force that stretches the slits 4a tends to concentrate on the outer side in the X direction (i.e., the four corners) of the one end edge 3a and the other end edge 3b of the top surface 3. Therefore, the edge non-buffering portions 7E are provided in tapered regions at the one end edge 3a and the other end edge 3b of the top surface 3 and their vicinity, where the dimension in the Y direction increases as it moves outward in the X direction. These edge non-buffering portions 7E can prevent damage to the four corners of the top surface 3, which are particularly susceptible to damage to the slits 4a. In this way, damage to the slits 4a of the buffering portions 4 provided on the top surface 3 can be further prevented.

[0057] (5) Because the buffer sections 4 are provided on both sides of the center section 7C provided in the center of the top surface 3, the area of ​​the top surface 3 where the buffer sections 4 are provided is divided into two by the center section 7C. In this way, the area of ​​the buffer sections 4 on the top surface 3 is appropriately narrowed, which also helps to prevent excessive stretching of the notches 4a. As a result, damage to the notches 4a provided in the buffer sections 4 can be prevented.

[0058] Furthermore, when the packaging bag 1 is carried while suspended from the center portion 7C after the contents are placed inside, the weight of the packaging bag 1 and the contents causes the buffer portions 4 provided on both sides of the center portion 7C to be pulled by a force having a vertical component, thereby absorbing vertical vibrations and shocks during carrying. Therefore, the protection of the contents can be improved when the packaging bag 1 is carried by the user.

[0059] (6) By providing a hand hole 7H in the inextensible center portion 7C provided in the center of the top surface portion 3, the user of the packaging bag 1 can easily carry the bag by hooking their fingers through the hand hole 7H. (7) The packaging bag 1, which has an opening 9 surrounded by one edge 2a and one edge 3a of the bottom surface portion 2 and the top surface portion 3 and has tongues 8, 8' that close the opening 9, can be constructed simply by adding a slit portion 4a or the like to an existing gussetless envelope. In other words, the packaging bag 1 can be manufactured by utilizing existing envelopes.

[0060] For example, contents are stored in an upright position with the bottom surface 2 and top surface 3 aligned vertically, and the contents are stored, displayed, exhibited, sold, and carried in a lying position with the bottom surface 2 and top surface 3 aligned horizontally. Since the upright position when storing contents is different from the lying position thereafter, this contributes to improving the ease of each operation performed in each position, such as storage work performed in an upright position and carrying work performed in a lying position.

[0061] (8) In a structure in which the tongue 8 extends from the entire one edge 3a of the top surface portion 3, when the tongue 8 is bonded to the bottom surface portion 2, stress is concentrated at a portion of the one edge 3a on the outer side in the X direction, which may result in warping or damage to the portion where the stress is concentrated. In contrast, in a structure in which the tongue 8' extends from only a portion of the one edge 3a of the top surface portion 3, the area from which the tongue 8' extends is limited to a portion of the one edge 3a of the top surface portion 3. This makes it possible to prevent warping or damage to the top surface portion 3 due to stress concentration, and ultimately to prevent damage to the notch 4a.

[0062] (9) Alternatively, if creases 8C, 8C' extending along the X direction are provided at the Y-direction center of the tongues 8, 8', the creases 8C, 8C' that fold back the tongues 8, 8' are offset in the Y1 direction relative to one edge 3a of the top surface 3. This reduces the concentration of tensile force that may be applied to the top surface 3, particularly in the Y1-direction region, when the opening 9 is closed by the tongues 8, 8'. This also helps prevent warping and damage to the top surface 3, and also prevents damage to the slits 4a. (10) Furthermore, packaging bags 1 made of kraft paper do not require the use of resin materials (promoting the so-called "plastic-free" movement) compared to packaging bags made of resin, and can be recycled as waste paper.

[0063] [II. Modifications] The above-described embodiment is merely illustrative, and does not intend to exclude various modifications or applications of techniques not explicitly stated in this embodiment. Each configuration of this embodiment can be modified in various ways without departing from the spirit thereof. Furthermore, they can be selected and combined as needed. The packaging bag is an envelope-type bag without a gusset, and is provided with an inextensible non-cushioned portion having at least a top non-cushioned portion and a bottom non-cushioned portion, and an extensible cushioning portion. For example, the flap and hand holes may be omitted from the packaging bag, and the paper material used for the packaging bag is not limited to kraft paper.

[0064] Furthermore, the non-buffered edge portions may be provided in any region, not just a tapered region, as long as they are provided in an area including at least the edge in the Y direction. However, the non-buffered top surface portion may have at least a center portion, and in one embodiment, the buffering portions may be provided in the region where the non-buffered edge portions are provided. In this case, the region where the buffering portions are provided is wider than the region where the buffering portions described above are provided in one embodiment, making the container more susceptible to deformation when contents are placed inside, improving the container's ability to accommodate the contents. On the other hand, the buffering portions may be provided only on either the Y1 direction side or the Y2 direction side of the center portion. In this case, the region where the buffering portions are provided is smaller than the region where the buffering portions described above are provided in one embodiment, further reducing damage to the buffering portions.

[0065] Alternatively, the slits and the non-cushioning top portion are not limited to extending in the predetermined direction described above in one embodiment, but may extend in any direction in the XY plane. The slits and the non-cushioning top portion may extend in different directions. An example of a non-cushioning top portion extending in a direction different from the slits is a configuration in which multiple slits extend along the Y direction and a non-cushioning top portion extends along the X direction. In one embodiment, in a packaging bag 1 in which contents are inserted or removed along the Y direction as described above, in a buffer portion 4 having slits 4a extending along the X direction, the direction in which the contents are inserted or removed (here, the Y direction) intersects with the direction in which the slits 4a extend (here, the X direction), so the inserted or removed contents may get caught in the slits 4a. In contrast, a buffer section provided with multiple notches extending along the Y direction, the same direction in which the contents are inserted and removed, makes it less likely for the inserted and removed contents to get caught in the notches, thereby reducing damage to the notches and helping to improve the storage and removal capacity of the contents.

[0066] 1 Packaging bag 2 Bottom part 2a One end edge 3 Top part 3a One end edge 3b Other end edge 4 Buffer part 4a Notch part 4b Non-notch part 40 Buffer cell 41-46 Piece part 51-56 Wall part 5 Non-buffer part 6 Bottom non-buffer part 7 Top non-buffer part 7E Edge non-buffer part 7C Center part 7H Hand hole 8, 8' Tongue piece 8C, 8C' Ruled line 9 Opening

Claims

1. A gussetless envelope-type packaging bag in which top and bottom surfaces extending along both a first direction and a second direction perpendicular to the first direction are overlapped without a gusset in the thickness direction perpendicular to the first and second directions, the packaging bag comprising: a stretchable buffer section provided in at least a portion of the top surface excluding the central portion in the first direction, with a plurality of slits arranged in a staggered pattern; and a non-buffering section that is not provided with slits and is non-stretchable, wherein the non-buffering section comprises a top non-buffering section provided in parts of the top surface excluding the area where the buffering section is provided, and a bottom non-buffering section provided over the entire area of ​​the bottom surface.

2. The packaging bag according to claim 1, characterized in that the top surface non-buffering portion extends along a predetermined direction in a plane along both the first direction and the second direction, and the buffering portion has a plurality of the notches extending along the predetermined direction arranged in a staggered pattern.

3. The packaging bag according to claim 1 or 2, characterized in that the top surface non-cushioning portion has an edge non-cushioning portion provided in an area including the edge in the first direction.

4. The packaging bag according to claim 3, characterized in that the edge non-buffering portion is provided in a tapered area in which the dimension in the first direction becomes longer as it goes outward in the second direction.

5. The packaging bag according to any one of claims 1 to 4, characterized in that the buffer sections are arranged on both sides of the central section in the first direction.

6. A packaging bag as claimed in any one of claims 1 to 5, characterized in that the non-cushioning portion of the top surface has a center portion provided in the central portion and having a hand hole drilled therein.

7. A packaging bag as described in any one of claims 1 to 6, characterized in that it has a tongue piece that closes an opening surrounded by one edge of each of the top and bottom surfaces, which is one edge in any direction in a plane along which both the first direction and the second direction are aligned, and that extends from either the top or bottom surface and is attached to the other of the top or bottom surface.

8. The packaging bag according to claim 7, wherein the tongue extends from a portion of the one edge of either the top surface or the bottom surface.

9. The packaging bag according to claim 7 or 8, wherein the tongue has a fold line extending along the second direction at the center in the first direction.

10. The packaging bag according to any one of claims 1 to 9, characterized in that it is made of kraft paper.

Images