JP7716616B2 - food packaging bags - Google Patents

Description

The present invention relates to a food packaging bag for packaging food.

Some foods, such as sandwiches, have a triangular (usually right-angled) side shape or a similar shape, and are finished in a three-dimensional shape with a specified thickness or width. Food packaging bags for packaging such foods are commonly shown in Figures 28 and 29(a), and a newer one is known, such as that described in Patent Document 1.

The food packaging bag 1' comprises a bag body 10' and a header portion 15'. The bag body 10' is made by overlapping a pair of sheets 2', 3', each of which is wider at one end than the other, and is sealed on three sides by a top joint 11' at one end and side joints 12', 12' on both sides, with the other end forming an opening 13'. The header portion 15' is formed by joining the protruding pieces of each sheet 2', 3' protruding from the top joint 11' at appropriate locations to form an integrated bag.

The second sheet 3' in the header section 15' has an inverted U-shaped cut line 32', for example, and a tear strip 33' with the cut line 32' as its outline. A tear strip 34', such as cutting tape, is attached to the inner surface of the second sheet 3', extending from the tear strip 33' to the other end of the second sheet 3'.

When eating food packaged in the food packaging bag 1', the tear strip 33' is grasped and pulled down, as shown in Figure 29(b). This pulls the tear strip 34', causing the second sheet 3' to break along both side edges of the tear strip 34', forming a tearable opening in the second sheet 3'. The food can be removed from this tearable opening.

JP 2017-171326 A

This type of food packaging material is made solely from plastic sheets. However, waste plastic has become a global environmental problem, making reducing plastic usage an urgent issue.

Therefore, the present invention was made in consideration of these circumstances, and its objective is to provide a food packaging bag that reduces the amount of plastic used while also providing added value beyond this.

The food packaging bag according to the present invention comprises:
a bag body including a pair of overlapping sheets each having a shape in which one end is wider than the other end in a first direction, the bag body being sealed on three sides by a top joint at one end and side joints at both sides, the other end being an opening , and the inside being a portion for containing food ;
At least one of the pair of sheets is divided into three regions, a central region and two side regions, by two boundary lines in a second direction perpendicular to the first direction, the boundary lines being spaced apart by 90% or less of the width of the top joint, which corresponds to the width of the food storage section, and the sheet comprises a central sheet and two side sheets, and has joints at the overlapping portions where the side edges of the central sheet and the side sheets meet, the central region is the portion of the central sheet excluding the overlapping portions of the both side edges, and the side sheets are the side regions , and when food is stored in the food storage section, portions of the two side sheets within a predetermined width from each side edge can be folded along fold lines ,
This is a food packaging bag in which each area and the other sheet when not divided into multiple areas are selectively made of either a plastic sheet, a paper sheet or a cellophane sheet, and a pair of sheets are partially made of a paper sheet or a cellophane sheet.

Here, as one embodiment of the food packaging bag according to the present invention,
The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
The distance between the inner edges of the two joints is smaller than the width of the apex joint, and the distance between the outer edges of the two joints is larger than the width of the apex joint.
The above configuration can be adopted.

In addition, as one aspect of the food packaging bag according to the present invention,
The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
A configuration can be adopted in which the distance between the inner edges of the two joints is smaller than the width of the apex joint, and the distance between the outer edges of the two joints is the same as the width of the apex joint .

In addition, as one aspect of the food packaging bag according to the present invention,
The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
A configuration can be adopted in which the spacing between the inner edges of the two joints is equal to the width of the apex joint, and the spacing between the outer edges of the two joints is greater than the width of the apex joint .

As described above, according to the present invention, paper sheets or cellophane sheets are used in some parts. Therefore, according to the present invention, the amount of plastic used can be reduced.

Furthermore, according to the present invention, paper sheets or cellophane sheets, which have higher rigidity than plastic sheets, are used. Therefore, according to the present invention, the rigidity of the food packaging body can be improved.

FIG. 1 is an exploded perspective view of a food packaging bag according to one embodiment of the present invention. FIG. 2 is a front view of the food packaging bag. FIG. 3 is a rear view of the food packaging bag. Fig. 4(a) is an outer view of the first sheet of the food packaging bag, and Fig. 4(b) is a cross-sectional view taken along line AA of Fig. 4(a). Fig. 5(a) is an outer view of the second sheet of the food packaging bag, and Fig. 5(b) is a cross-sectional view taken along line BB of Fig. 5(a). 6(a) to 6(c) are explanatory diagrams showing the process of packaging food using the food packaging bag. 7(a) to 7(d) are explanatory diagrams continuing from FIG. Fig. 8(a) is a perspective view of a food package packaged in the food packaging bag as seen from the front side, and Fig. 8(b) is a cross-sectional view taken along line CC of Fig. 8(a). FIG. 9 is an explanatory diagram of an initial step in the first method of manufacturing the food packaging bag. FIG. 10 is an explanatory diagram of the process following FIG. FIG. 11 is an explanatory diagram of the process following FIG. FIG. 12 is an explanatory diagram of a process different from those in FIGS. FIG. 13 is an explanatory diagram of the process following FIG. 11 or FIG. FIG. 14 is an explanatory diagram of the process following FIG. FIG. 15 is an explanatory diagram of the process (final process) following FIG. FIG. 16 is an explanatory diagram of an initial step in the second method of producing the food packaging bag. FIG. 17 is an explanatory diagram of a process different from that shown in FIG. FIG. 18 is an explanatory diagram of the process following FIG. 16 or FIG. FIG. 19 is an explanatory diagram of the process following FIG. FIG. 20 is an explanatory diagram of the process following FIG. FIG. 21 is an explanatory diagram of the process following FIG. FIG. 22 is an explanatory diagram of the subsequent step (final step) of FIG. Fig. 23(a) is a cross-sectional view of a first sheet of a food packaging bag according to another embodiment, and Fig. 23(b) is a transverse cross-sectional view of a food package packaged in the food packaging bag. FIG. 24 is a front view of a packaging bag for food according to still another embodiment. Fig. 25(a) is a perspective view of a food package packaged in the food packaging bag as seen from the front side, and Fig. 25(b) is a cross-sectional view taken along line DD of Fig. 25(a). Fig. 26(a) is a cross-sectional view of a food package packaged in a food packaging bag according to another embodiment, and Fig. 26(b) is a cross-sectional view of a food package packaged in a food packaging bag according to yet another embodiment. FIG. 27 is a front view of a packaging bag for food according to yet another embodiment. FIG. 28 is a front view of a conventional food packaging bag. Fig. 29(a) is a perspective view of a food package packaged in the food packaging bag, as seen from the front side, and Fig. 29(b) is a perspective view of the food package being opened.

Below, we will explain one embodiment of a food packaging bag according to the present invention, which is a food packaging bag used to package sandwiches, with reference to Figures 1 to 8.

As shown in Figures 1 to 3, the food packaging bag 1 according to this embodiment comprises a bag body 10 and a header portion 15. The bag body 10 is formed by overlapping and joining a pair of sheets (a first sheet 2 and a second sheet 3). The first sheet 2 is also referred to as the top sheet, and the second sheet 3 is also referred to as the back sheet. The pair of sheets are shaped such that one end is longer than the other in mutually orthogonal directions, and the other end is wider than the other end. The bag body 10 is joined and sealed on three sides by a top joint 11 at one end and side joints 12, 12 on both sides, and the other end forms an opening 13. The header portion 15 is formed by joining the protruding pieces of each sheet 2, 3 protruding from the top joint 11 at appropriate locations to form an integrated body. In the following, the one of the directions (the vertical direction in Figures 2 and 3) will be referred to as the "longitudinal direction" or "first direction," and the other direction (the horizontal direction in Figures 2 and 3) will be referred to as the "width direction" or "second direction."

As shown in Figure 4, the first sheet 2 has a body portion 20 and a tip portion 21 (the protruding piece). The body portion 20 has a shape that gradually widens from one end to the other. The tip portion 21 has a narrow shape that extends from one end of the body portion 20.

The first sheet 2 is divided into three regions: a central portion 22 and two side portions 23, 23, by two parallel boundary lines B, B that run along the longitudinal direction and are spaced apart in the width direction. The central portion 22 is divided into the center and tip portions 21 of the body portion 20. The side portions 23 are divided into the sides of the body portion 20.

The first sheet 2 is made up of three sheets (a central sheet 24 and two side sheets 25, 25) that are overlapped at their side edges (overlapped portion 26) and then joined by heat sealing at the overlapped portion 26 (jointed portion 27) to form a single sheet. At the overlapped portion 26, the side edges of the side sheets 25 are positioned on the outer surface of the side edges of the central sheet 24, and the side edges of the central sheet 24 and the side sheets 25 are overlapped so that the outer surface of the side edges of the central sheet 24 faces the inner surface of the side edges of the side sheets 25.

The joint 27 is formed by heat-sealing the overlapping portion 26 along the side edges of the central sheet 24 and the side sheets 25 over the entire length. In this embodiment, the joint 27 is a strip-shaped seal of a predetermined width formed by welding using a heat seal bar. The width of the joint 27 is narrower than the width of the overlapping portion 26. As a result, the portion of the side edge of the central sheet 24 beyond the joint 27 and the portion of the side edge of the side sheets 25 beyond the joint 27 are free ends. In this embodiment, the joint 27 has a width of approximately 2 mm to 20 mm, and the free ends have a width of approximately 0 mm to 5 mm.

The central portion 22 corresponds to the central sheet 24 excluding the left and right overlapping portions 26, 26. The side portions 23 correspond to the side sheets 25. As a result, in the first sheet 2, the central portion 22 is a transparent portion that allows the interior to be seen, and the left and right side portions 23, 23 are opaque (or translucent) portions.

Here, the distance WB between the two boundary lines B, B (the width of the central portion 22) is smaller than the width W11 of the top joint 11 (the length of the inner edge of the top joint 11, with both ends being its intersection with the inner edges of the side joints 12 (see Figure 2), which corresponds to the width of the container section of the food package 6 described below or the width of the sandwich 5 (see Figure 8)). More specifically, the width WB is 35% or more, or 45% or more, and 97% or less, or 90% or less of the width W11.

Furthermore, the distance W27a between the inner edges of the two joints 27, 27 is smaller than the width W11 of the apex joint 11, and the distance W27b between the outer edges of the two joints 27, 27 is greater than the width W11 of the apex joint 11 (W27a < W11 < W27b). As a result, a perpendicular line passing through the endpoint of the inner edge of the apex joint 11 is parallel to the inner and outer edges of the joint 27 and passes between the inner and outer edges of the joint 27.

As shown in Figure 5, the second sheet 3 has a body portion 30 and a tip portion 31 (the protruding piece). The body portion 30 has a shape that gradually widens from one end to the other. The tip portion 31 has a narrow shape that extends from one end of the body portion 30.

Each of the sheets 24, 25, and 3 is selectively made from one of the different materials listed below.

<Plastic sheet>
The sheet is a heat-sealable plastic sheet (film) made of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), or the like. For example, the sheet is a biaxially oriented polypropylene (OPP) sheet (film) or a non-oriented polypropylene (CPP) sheet (film). Alternatively, the sheet is a laminated sheet (film). As one form of laminated sheet (film), the sheet is formed by laminating, from the outer surface side, a base layer, an adhesive layer, and a resin layer. Resins such as polyethylene terephthalate (PET), polypropylene (PP), and polyethylene (PE) are used as the base layer. Dry lamination, extrusion lamination, and the like are used as the adhesive layer. Resins such as polypropylene (PP) and polyethylene (PE) are used as the resin layer. The term "polypropylene sheet (film)" refers not only to 100% pure polypropylene sheets (films), but also to sheets (films) containing polypropylene as the main component and other components (e.g., other resin components such as polyethylene). It should be noted that the term "sheet" is not defined by thickness, but is a concept that includes film (the same applies hereinafter).

<Paper sheet>
The sheet may be made of paper, unbleached kraft paper, Japanese paper, mixed paper, synthetic paper, glassine paper, paper-like material, or a sheet (film) primarily made of these materials (collectively referred to as "paper"). The paper may contain bio-based polyethylene terephthalate (bio-based PET, or so-called bioPET). The sheet may have heat-weldability on the inner surface, either entirely or partially, as needed. For example, the sheet may be a laminated sheet (film) in which paper is used as the outer layer and a plastic sheet (film) is used as the inner layer. One form of laminated sheet (film) is formed by laminating, from the outer surface side, a substrate layer, an adhesive layer, and a resin layer. Paper is used as the substrate layer. Dry lamination, extrusion lamination, etc. are used as the adhesive layer. Resins such as polypropylene (PP) and polyethylene (PE) are used as the resin layer. As an example, the base layer is paper having a basis weight of about 12 g/m ² or about 15 g/m ² , the adhesive layer is a dry laminate, and the resin layer is biaxially oriented polypropylene (OPP).

<Cellophane sheet>
The sheet is a sheet (film) made of ordinary cellophane, moisture-proof cellophane, cellophane-based, or cellophane-like material (collectively referred to as "cellophane"), or primarily made of these materials (collectively referred to as "cellophane sheet" (film)). The sheet may have heat-sealing properties on the inner surface, either entirely or partially where necessary. For example, the sheet may be a laminated sheet (film) in which cellophane is used as the outer layer and a plastic sheet (film) is used as the inner layer. One form of laminated sheet (film) is formed by laminating, from the outer surface side, a base layer, an adhesive layer, and a resin layer. Cellophane is used as the base layer. Dry lamination, extrusion lamination, etc. are used as the adhesive layer. Resins such as polypropylene (PP) and polyethylene (PE) are used as the resin layer. As an example, the base layer is ordinary cellophane or moisture-proof cellophane, the adhesive layer is dry laminate, and the resin layer is biaxially oriented polypropylene (OPP).

<Combination>
Examples of combinations of seat materials include the following:

Note that these patterns include a pattern in which the lower end of the second sheet 3 (the portion on the opening 13 side) is a plastic sheet. As mentioned above, the lower end of the second sheet 3 is the portion that is folded first when packaging the sandwich 5 (see Figure 6(c)). Because the lower end of this second sheet 3 is a plastic sheet that is softer and/or less prone to curling than a paper sheet or cellophane sheet, it can be folded neatly, and ultimately the opening 13 can be closed reliably and neatly.

As shown in Figures 1 to 3, in this embodiment, the body portions 20, 30 are trapezoidal, and the tip portions 21, 31 are rectangular. Therefore, one end of the body portions 20, 30 (and the corresponding other end of the tip portions 21, 31) is linear and perpendicular to the longitudinal direction. In other words, one end of the body portions 20, 30 is linear and parallel to the width direction. Both side edges of the body portions 20, 30 are linear and inclined relative to the longitudinal direction. Both side edges of the tip portions 21, 31 are also linear and inclined relative to the longitudinal direction. However, both side edges of the tip portions 21, 31 may also be linear and parallel to the longitudinal direction. The other end sides of both side edges of the body portions 20, 30 are missing by cutouts 14. As a result, the other end sides of the body portions 20, 30 are narrower by the width of the cutouts 14.

The top joint 11 is formed by heat-sealing the first and second sheets 2, 3 along one edge of the body 20, 30. In this embodiment, the top joint 11 is formed by welding using a heat seal bar and is a strip-shaped seal having a predetermined width.

The side joints 12 are formed by heat-sealing the first and second sheets 2, 3 along the side edges (oblique sides) of the body portions 20, 30 and the side edges (oblique sides or vertical sides) of the tip portions 21, 31. In this embodiment, the side joints 12 are formed by welding using a heat seal bar, and are strip-shaped seals of a predetermined width. The width of the side joints 12 is smaller than the width of the top joint 11. Specifically, the side joints 12 have a width of approximately 2 mm to 5 mm.

The interior of the bag body 10 constructed in this manner serves as a food storage compartment. An inner sheet 4 is attached to the inner surface of the first sheet 2 (or the central sheet 24) of the bag body 10. The width W4 of the inner sheet 4 is smaller than the distance W27a between the inner edges of the two joints 27, 27. As a result, the inner sheet 4 is positioned so that its side edges 4a, 4a are inside the left and right joints 27, 27, without overlapping the left and right joints 27, 27. The inner sheet 4 is joined by heat sealing at the top joint 11, leaving a free end within the storage compartment. As a result, even if the food moves within the storage compartment, the inner sheet 4 adheres to the surface of the food and follows its movement. This prevents the first sheet 2 (or the central sheet 24) from becoming soiled or its appearance from being damaged.

A cut line 32 is formed in the second sheet 3 in the header section 15. The cut line 32 forms a tear-off strip 33 in the second sheet 3 in the header section 15. The tear-off strip 33 has the cut line 32 as its outline, a fixed end between both end points, and a free end at one end. In this embodiment, the cut line 32 is formed in an inverted U-shape. This results in the tear-off strip 33 being an upward-facing tongue.

The second sheet 3 is provided with a tear strip 34 as an opening means. The tear strip 34 is provided on the inner surface of the second sheet 3, extending from the tear strip 33 to the other end of the second sheet 3. The tear strip 34 is provided, for example, along the longitudinal direction at the center of the width of the second sheet 3. The tear strip 34 is joined to the inner surface of the second sheet 3 by heat sealing, adhesive, or the like. As an example, the tear strip 34 is joined to the inner surface of the second sheet 3 by heat sealing or self-adhesive after a coating agent is applied to this inner surface (the surface facing the second sheet 3). The tear strip 34 is, for example, cutting tape or thread. In this embodiment, the tear strip 34 is a strip of cutting tape with a width of 5 mm or more, or 10 mm or more. Cut tape is made from thin, heat-weldable plastic sheets such as biaxially oriented polyester, polyethylene terephthalate (PET), polyethylene (PE), polypropylene (PP), and biaxially oriented polypropylene (OPP).

The food packaging bag 1 according to this embodiment has the above configuration. Next, we will explain the method for packaging food using this food packaging bag 1.

First, as shown in Figure 6(a), the opening 13 is opened by blowing air at a predetermined pressure into the bag body 10 through the opening 13, or by using a suction head (not shown) to suck and lift the opening 13 side of the first sheet 2. Then, in this state, the sandwich 5 is inserted into the bag body 10.

When the sandwich 5 is placed inside the bag body 10, the opening shape of the opening 13 becomes rectangular, as shown in Figure 1(b). The portions spanning the side joints 12 of the first sheet 2 and the second sheet 3 form a pair of opposing triangular side portions. The middle portion of the first sheet 2 forms a rectangular front portion. The middle portion of the second sheet 3 forms a rectangular back portion.

After the sandwich 5 is placed in the bag body 10, as shown in FIG. 7(c), first, of the excess sheet pieces (those sticking out from the bottom of the sandwich 5) at the opening 13, the sheet piece (the back sheet piece) of the second sheet 3 is folded over to cover the bottom of the sandwich 5. Next, as shown in FIG. 7(a), one of the left or right sheet pieces (one of the side sheet pieces) is folded over so that it overlaps the previously folded second sheet 3. Next, as shown in FIG. 7(b), the other of the left or right sheet pieces (the other side sheet piece) is folded over so that it overlaps the previously folded second sheet 3. Next, as shown in FIG. 7(c), the remaining sheet piece (the front sheet piece) of the first sheet 2 is folded over so that it overlaps the previously folded left or right sheet pieces. This closes the opening 13 of the food packaging bag 1.

However, the order in which the four sheet pieces are folded is not particularly limited; for example, the sheet piece on the front side is folded first, then the sheet piece on the side side, and finally the sheet piece on the back side; or the sheet piece on either the back or front side is folded first, then the other sheet piece on either the back or front side, and finally the sheet piece on the side side; or the sheet piece on the side side is folded first, then the sheet piece on either the back or front side, and finally the other sheet piece on either the back or front side.

Once the opening 13 is closed, tape 7 is applied to seal the opening 13. Alternatively, a label may be applied, or the folded and overlapping sheet pieces may be joined at predetermined locations using heat sealing or the like to seal the opening 13.

Through the above steps, the food package 6 is completed, as shown in Figure 8(a). The food package 6 is kept airtight by the top joint 11, side joints 12, 12, and the closed portion (bottom portion) of the sealed opening 13. This prevents outside air from entering the interior, ensuring that the packaged sandwich 5 maintains its intended quality.

As shown in Figure 8(b), in the completed food package 6, the side portions 6a2 of the front portion 6a, the side portions 6b, and the back portion 6c of the food package 6 are made up of the left and right side sheets 25, 25 (left and right side portions 23, 23) and the second sheet 3. The main portion 6a1 of the front portion 6a of the food package 6, excluding the side portions 6a2, is made up of the center sheet 24 (center portion 22).

The left and right corners on the back side of the sandwich 5 are covered by the folded portions of the second sheet 3, and the left and right corners on the front side of the sandwich 5 are covered by the folded portions of the left and right side sheets 25, 25 of the first sheet 2. In other words, in the food package 6, four angled pillars are formed at the four corners of the sandwich 5, extending along the sides of the corners of the sandwich 5.

When eating the sandwich 5, the opening strip 33 is picked up and pulled down. The opening strip 33 is joined to one end of the opening strip 34. Therefore, when the opening strip 33 is picked up and pulled down, the opening strip 34 is pulled, and the second sheet 3 is torn along both side edges of the opening strip 34, forming a tearable opening in the second sheet 3. The sandwich 5 can be removed from this tearable opening.

As described above, the food packaging bag 1 according to this embodiment uses a paper sheet or cellophane sheet for part of the sheets 2 and 3. Therefore, the food packaging bag 1 according to this embodiment can reduce the amount of plastic used. In recent years, waste plastic has become a global environmental problem, and the food packaging bag 1 according to this embodiment provides an effective solution to this environmental issue.

In addition, paper sheets and cellophane sheets are more rigid than plastic sheets. This gives sheets 2 and 3 more rigidity, which improves the self-standing ability of the food package 6 once it is assembled. The rigidity of sheets 2 and 3 also improves the rigidity of the food package 6. Therefore, the food packaging bag 1 according to this embodiment is highly effective in preventing the sandwich 5 from losing its shape.

Furthermore, with the food packaging bag 1 according to this embodiment, when the food package 6 is completed, four angled columns made of paper or cellophane sheets can be formed at the four corners of the food package 6 that face the four corners of the sandwich 5 (in cross section). These columns extend along the four corners of the sandwich 5. In this case, the food package 6 has high rigidity in the vertical direction. During product distribution, the food packages 6 are stacked not only horizontally but also vertically in a transport tray to fill the triangular space. Conventional food packages made solely of plastic sheets have low rigidity in the vertical direction, and stacking the food packages can cause vertical compressive forces to act on the sandwich, resulting in crushing the sandwich. However, with the food packaging bag 1 according to this embodiment, the food package 6 has high rigidity in the vertical direction, effectively preventing the sandwich from being crushed.

Furthermore, paper sheets and cellophane sheets are more susceptible to creases than plastic sheets. Therefore, when the angled column is made of paper or cellophane, the sheet 2 bends sharply at each side of the food package 6, giving the food package 6 a sharp appearance. Therefore, the food packaging bag 1 according to this embodiment has the effect of providing excellent appearance, stability, and self-standing ability in the completed food package 6.

Furthermore, when packaging sandwiches 5 using the food packaging bag 1 according to this embodiment, the excess sheet pieces around the opening 13 are folded to close the opening 13 (see Figures 6(c) and 7(a) to (c)). However, all four excess sheet pieces around the opening 13 contain paper or cellophane sheets, which are prone to creases. With conventional food packaging bags made solely of plastic sheets, the elastic repulsive force of the sheet causes the excess sheet pieces to return to their original shape even after folding, preventing a smooth closing operation. However, with the food packaging bag 1 according to this embodiment, the folded excess sheet pieces are less likely to return to their original shape, allowing for a smooth closing operation of the opening 13.

Furthermore, with the food packaging bag 1 according to this embodiment, the side joints 12 are formed in a strip shape with a predetermined width along the side edges of the bag body 10 and the header portion 15. As a result, when the food packaging bag 6 is completed, the side joints 12 are in a folded-back position as shown in FIG. 8. This causes the header portion 15 to stand upright due to the formation of pillars on both sides. Furthermore, the header portion 15 is in a flat position extending straight from the front of the bag body 10. Therefore, with the food packaging bag 1 according to this embodiment, the food packaging bag 6 not only has an attractive appearance, but also makes the markings on the header portion 15 easier to see when displayed in a store such as a convenience store.

Next, we will explain the manufacturing method for the food packaging bag 1 according to this embodiment. There are two main manufacturing methods.

<First manufacturing method>
The first manufacturing method is shown in Figures 9 to 15. The first manufacturing method includes:
i) preparing a tube having a circumferential portion with a predetermined width, the circumferential portion being flattened so as to be located at the center of one surface, as shown in Figures 9 to 13;
ii) forming a band-like joint portion that will become the top joint portion 11 on the tube in the width direction of the tube, as shown in FIG. 13;
iii) forming a band-like joint portion on the tube, which will become the side joint portion 12, obliquely with respect to the side edge of the tube, as shown in FIG. 14;
iv) cutting the tube in the width direction at the tip of the portion that will become the header portion 15, as shown in FIG.
and v) cutting the tube obliquely along the widthwise middle of the joint that will become the side joint 12, as shown in FIG.
The first manufacturing method further comprises:
vi) As shown in FIG. 15, a step of forming the notch 14 is included.

Step i) comprises:
ii) as shown in FIG. 9, a step of attaching an opening strip 34 to the inner surface of the main sheet roll 2, 3X along the longitudinal direction of the sheet roll;
i-ii) forming cut lines 32 at regular intervals along the longitudinal direction of the sheet material on the opening strip 34 as shown in FIG.
i-iii) As shown in FIG. 10 and FIG. 11 or FIG. 12, a step of conveying the belt-shaped central sheet raw material 24X and the main sheet raw material 2, 3X along the longitudinal direction of the sheet raw material;
i-iv) overlapping the side edge of the central sheet raw material 24X with the side edge of the main sheet raw material 2, 3X as shown in FIG. 11 or 12;
iv) As shown in FIG. 13, the method includes a step of forming a joint 27 in the overlapping portion along the longitudinal direction of the raw sheet.
Steps i-iii) further comprise:
i-iii-i) As shown in FIG. 11 or 12, the process includes a step of conveying the inner sheet material 4X in the longitudinal direction of the sheet material so as to follow the inner surface of the central sheet material 24X.

In steps i-iii) and i-iv), as shown in Figures 10 and 11, both side edges of the main sheet rolls 2, 3X may be folded inward, and then a center sheet roll 24X (and inner sheet roll 4X) may be inserted between the both side edges. Alternatively, as shown in Figure 12, the center sheet roll 24X (and inner sheet roll 4X) may be supplied and conveyed to the widthwise center of the main sheet rolls 2, 3X, and then both side edges of the main sheet rolls 2, 3X may be folded inward. In either case, the folded side edges of the main sheet rolls 2, 3X become side sheet rolls 25X, 25X, and the unfolded center portion becomes the second sheet roll 3X.

The order of steps ii) through vi) can be changed as appropriate, as long as production is possible. Furthermore, steps i) through v) may be performed by continuously transporting the raw sheet, or by intermittently transporting it.

Thus, with the first manufacturing method, both sides of the tube are cut off in a triangular shape, resulting in loss. However, the longitudinal direction (feed direction) of the second sheet material 3X and the direction of the tearing strip 34 are aligned. Therefore, in the food packaging bag 1, the tearing strip 34 is aligned with the tearing direction of the second sheet 3. Therefore, food packaging bags 1 manufactured using the first manufacturing direction can be made easier to open.

<Second manufacturing method>
The second manufacturing method is shown in Figures 16 to 22. The second manufacturing method includes:
i) preparing a first sheet material 2X as shown in FIGS. 16 and 17;
ii) preparing a second sheet material 3X as shown in FIG. 18;
iii) as shown in FIG. 19, a step of overlapping the first sheet raw roll 2X and the second sheet raw roll 3X while inserting inner sheets 4 at a fixed pitch between the first sheet raw roll 2X and the second sheet raw roll 3X along the longitudinal direction of the sheet raw rolls;
iv) as shown in FIG. 20, a step of forming a joint portion to be the top joint portion 11 in a band shape along the longitudinal direction of the sheet raw sheet and in a staggered pattern in the longitudinal direction of the sheet raw sheet;
v) forming, as shown in FIG. 21 , a joining portion that becomes a side joining portion 12 on the overlapping sheets in a band-like shape diagonally relative to the width direction of the sheet raw material and in a staggered pattern in the longitudinal direction of the sheet raw material;
vi) as shown in FIG. 22, cutting the overlapped sheets obliquely along the widthwise middle of the joint that will become the side joint 12.
Furthermore, the second manufacturing method includes:
vii) As shown in FIG. 22, a step of forming the notch 14 is included.

Step i) is as shown in FIG.
ii) a step of alternately supplying sheets to be the center sheets 24 and the side sheets 25 in the width direction of the sheet;
i-ii) overlapping the side edge portions of the sheet to be the center sheet 24 with the side edge portions of the sheets to be the side sheets 25;
i-iii) forming a joint 27 at the overlapping portion along the longitudinal direction of the sheets.

Alternatively, step i) may be performed by, as shown in FIG.
ii) a step of supplying sheets to be the side sheets 25 on the outer surface of the central sheet raw material 24X along the width direction of the sheet raw material and along the longitudinal direction of the sheet raw material at a constant pitch;
i-ii) forming joints 27 along the longitudinal direction of the sheets at the overlapping portions of the side edges of the central sheet raw material 24X and the sheets that will become the side sheets 25. The food packaging bag 1 manufactured through the steps of Figure 17 has the shape shown in Figure 23.

Step ii) is as shown in FIG.
ii-i) a step of attaching opening strips 34 to the inner surface of the second sheet raw material 3X at regular intervals along the width direction of the sheet raw material and along the longitudinal direction of the sheet raw material;
ii-ii) forming staggered cut lines 32 in the longitudinal direction of the sheet material on the opening strip 34.

The order of steps iv) through vii) can be changed as appropriate, as long as production is possible. Furthermore, steps i) through vi) may be performed by continuously transporting the raw sheet, or by intermittently transporting it.

In this way, according to the second manufacturing method, trapezoidal food packaging bags 1 are manufactured so that they are oriented transversely to the longitudinal direction of the raw sheet and in alternating opposite directions. This eliminates or reduces sheet waste.

The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

In the above embodiment, the distance W27a between the inner edges of the two joints 27, 27 is smaller than the width W11 of the top joint 11, and the distance W27b between the outer edges of the two joints 27, 27 is larger than the width W11 of the top joint 11 (W27a < W11 < W27b). This causes the joints 27 to bend to form an angled column (see Figure 8). However, the present invention is not limited to this. For example, as shown in Figures 24 and 25, the distance WB between the two boundary lines B, B may be narrowed so that the distance W27b between the outer edges of the two joints 27, 27 matches the width W11 of the top joint 11. In this case, the outer edge of the joint 27 is located at the fold line between the front portion 6a and the side portion 6b of the food package 6. The joints 27 are a portion whose rigidity is further increased by the joining. This allows the side sheets 25 to be folded neatly along the outer edges of the joints 27.

In the above embodiment, the central sheet 24 is disposed on the inner surface of the side sheets 25. However, the present invention may also be configured in the opposite manner. That is, as shown in FIG. 26, in the overlapping portion 26, the side edges of the side sheets 25 may be disposed on the inner surface of the side edges of the central sheet 24, and the side edges of the central sheet 24 and the side sheets 25 may be overlapped so that the inner surface of the side edge of the central sheet 24 faces the outer surface of the side edge of the side sheet 25. In this case, the side sheets 25 have heat-weldability on the outer surface as well as on the inner surface.

In the example shown in Figure 26(a), like Figure 25(b), the distance W27b between the outer edges of the two joints 27, 27 matches the width W11 of the top joint 11. In the example shown in Figure 26(b), the distance W27a between the inner edges of the two joints 27, 27 matches the width W11 of the top joint 11. In both cases, the side edges of the joints 27 are located at the fold lines of the front portion 6a and side portions 6b of the food package 6. Therefore, the side sheets 25 can be folded neatly along the side edges of the joints 27, which have increased rigidity.

Furthermore, in the above embodiment, the distance WB between the two boundary lines B, B that divide the first sheet 2 into three regions, the central region 22 and the two side regions 23, 23, is smaller than the width W11 of the top joint 11. However, the present invention is not limited to this. The distance between the two boundary lines may be larger than the width of the top joint.

In addition, in the above embodiment, the tearing strip 34 and inner sheet 4 are arranged over the entire length of the first sheet 2, from one end to the other. However, the present invention is not limited to this. For example, as shown in FIG. 27, the tearing strip 34 and inner sheet 4 may be arranged to have a length shorter than the entire length of the first sheet 2. This food packaging bag 1 can be manufactured using the second manufacturing method.

In the above embodiment, the opening means is a strip for opening. However, the present invention is not limited to this. Various known opening means can be used, such as perforations, half-cuts (half-cut lines), or a combination of these with a strip for opening.

Furthermore, a header portion is not essential for food packaging bags. For example, a food packaging bag may not have a header portion and may consist only of a bag body.

In addition, terms that specify a shape, part, or state, such as "trapezoid," "triangular," "rectangular," "rectangular," "straight line," "center," "end," "side," "coincidence," "identical," "parallel," and "orthogonal," in this invention include not only the thing itself, but also the concept of "approximately" which means something close to or similar to it.

In the above embodiment, the food is a sandwich. However, the food to be packaged may be Western confectionery such as cake, Japanese confectionery such as castella, bread, or cooked rice foods such as rice balls, as long as it can be placed in a food packaging bag; the type of food is not particularly limited.

In the above embodiment, the second sheet 2 is a single sheet. However, the present invention is not limited to this. The second sheet may be formed from multiple sheets (films), such as two sheets (films) joined at their side edges to form a single sheet, or three sheets (films) joined at their side edges to form a single sheet. In other words, not only the first sheet but also the second sheet may be divided into multiple regions in the width direction.

1...food packaging bag, 10...bag body, 11...top joint, 12...side joint, 13...opening, 14...notch, 15...header, 2...first sheet, 2, 3X...main sheet raw material, 20...body portion, 21...tip portion, 22...center portion, 23...side portion, 24...center sheet, 24X...center sheet raw material, 25...side sheet, 25X...side sheet raw material, 25Xa...side edge, 26...overlap portion, 27...joint portion, 3...second sheet, 3X...second sheet raw material, 30...body portion, 31...tip portion, 32...score line, 33 ...Tear strip, 34...Tear strip, 4...Inner sheet, 4X...Inner sheet roll, 4a...Side edge, 5...Sandwich, 6...Food package, 6a...Front portion, 6a1...Main portion, 6a2...Side portion, 6b...Side portion, 6c...Back portion, 7...Tape, B...Boundary line, W11...Width of top joint 11 (length of inner edge of top joint 11), WB...Spacing between two boundary lines B, B (width of center portion 22), W27a...Spacing between inner edges of two joints 27, 27, W27b...Spacing between outer edges of two joints 27, 27, W4...Width of inner sheet 4

Claims (4)

a bag body including a pair of overlapping sheets each having a shape in which one end is wider than the other end in a first direction, the bag body being sealed on three sides by a top joint at one end and side joints at both sides, the other end being an opening , and the inside being a portion for containing food ;
At least one of the pair of sheets is divided into three regions, a central region and two side regions, by two boundary lines in a second direction perpendicular to the first direction, the boundary lines being spaced apart by 90% or less of the width of the top joint, which corresponds to the width of the food storage section, and the sheet comprises a central sheet and two side sheets, and has joints at the overlapping portions where the side edges of the central sheet and the side sheets meet, the central region is the portion of the central sheet excluding the overlapping portions of the both side edges, and the side sheets are the side regions , and when food is stored in the food storage section, portions of the two side sheets within a predetermined width from each side edge can be folded along fold lines ,
A food packaging bag in which each area and the other sheet when not divided into multiple areas are selectively made of either a plastic sheet, a paper sheet, or a cellophane sheet, and a pair of sheets are partially provided with a paper sheet or a cellophane sheet. The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
The food packaging bag according to claim 1, wherein the distance between the inner edges of the two joints is smaller than the width of the top joint, and the distance between the outer edges of the two joints is greater than the width of the top joint. The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
The food packaging bag according to claim 1, wherein the distance between the inner edges of the two joints is smaller than the width of the top joint, and the distance between the outer edges of the two joints is the same as the width of the top joint. The side sheets are made of paper or cellophane.
The side edges of the central sheet and the side edges of the side sheets are overlapped so that the outer surface of the side edge of the central sheet faces the inner surface of the side edge of the side sheet, or so that the inner surface of the side edge of the central sheet faces the outer surface of the side edge of the side sheet,
the joint portion has a width narrower than the width of the overlapping portion so that a portion of the side edge portion of the center sheet beyond the joint portion and a portion of the side edge portion of the side sheet beyond the joint portion are free ends;
The food packaging bag according to claim 1, wherein the distance between the inner edges of the two joints is equal to the width of the top joint, and the distance between the outer edges of the two joints is greater than the width of the top joint.