bag-shaped container

Abstract

The present invention provides a bag-shaped container that enables smooth opening of the bag-shaped container by reducing the breaking load caused by the cutting line when pulling up the tear strip. [Solution] The present invention provides a bag-shaped container comprising a bag body formed by folding or overlapping a rectangular film to create a storage space, and a long tear strip fixed to the inside of the bag body and a zipper base laminated on its lower surface, wherein a cut line surrounding one end of the tear strip forms a gripping portion of the tear strip, and adjacent to the gripping portion, a cutting line is formed that crosses the zipper base in the width direction of the tear strip, and the user lifts the bag by holding the gripping portion, causing the tear strip and the zipper base to delaminate at the cutting line, and the base material layer of the tear strip to cut through the bag body, thereby opening the bag, wherein the bag-shaped container is characterized in that the cutting line acting on the tear strip is shortened by forming notches on one or both of the upper and lower edges in the width direction of the tear strip.

Description

Technical Field

[0001] The present invention relates to a bag-shaped container that is opened using a tear strip, and enables the tear strip to be pulled up with a smaller force by reducing the breaking load due to a cutting line formed on the tear strip.

Background Art

[0002] In recent years, bag-shaped containers that use a tear strip to tear the container surface and open it have been widely used. Until the container surface is torn using the tear strip, the composite film constituting the bag-shaped container minimizes the influence of outside air and light on the stored contents, and thus can reliably prevent deterioration of the stored contents such as oxidation during transportation and long-term storage.

[0003] In addition, by arranging a zipper tape parallel to the tear strip, a structure is proposed in which a once-opened bag-shaped container can be opened and closed again, and the quality of the contents of the bag-shaped container can be maintained for a predetermined period while taking out the contents in small portions.

[0004] As an example of this bag-shaped package, the following prior art exists.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] The bag-shaped container of Patent Document 1 described above has a structure in which a tear strip (tear guide strip) 21 is adhered to the back surface of the surface 11A of the same bag-shaped container, a cutting line (cutting line in the present application) 30 is formed on the surface 11A of the film constituting the bag-shaped container so as to surround one end of the tear strip, and a gripping portion (pinching portion) 3 of the tear guide strip 21 is formed at this portion.

[0007] Then, when the user grasps the gripping part 3 and pulls the tear strip 21 outwards from the film of the bag-shaped container, force is applied to the break line 30, which has a cut only on the surface layer, causing delamination of the tear strip 21, allowing the tear strip 21 to be pulled up while leaving a portion of it on the bag-shaped container side. The pulled-up tear strip 21 then cuts through the surface 11A, thus opening the container.

[0008] Thus, the lifting of the tear strip 21 is made possible by delamination caused by the fracture of the tear strip 21 along the fracture line 30. However, since the tear strip 21 has a certain width, the stress required to initiate this fracture is large.

[0009] Therefore, it was necessary to apply the stress required to break the bag-shaped container by holding it with one hand while pulling up the gripping part 3 with the other hand, but for children or women with weak strength, opening the bag-shaped container could be a great burden. [Overview of the project] [Problems that the invention aims to solve]

[0010] Therefore, the object of the present invention is to provide a bag-shaped container that enables smooth opening of the bag-shaped container by reducing the breaking load caused by the breaking line when the tear strip is pulled up. [Means for solving the problem]

[0011] To achieve the above objective, the bag-shaped container of the present invention is formed by a bag body that forms a storage space by folding or overlapping a rectangular film, and a long tear strip fixed to the inside of the bag body and a zipper base laminated on its lower surface, wherein a gripping portion of the tear strip is formed by a die-cut line surrounding one end of the tear strip, and adjacent to the gripping portion, a cutting line is formed that crosses the zipper base in the width direction of the tear strip, and when the user lifts the bag by holding the gripping portion, the tear strip and the zipper base delaminate at the cutting line, and the base material layer of the tear strip cuts the bag body, thereby opening the bag, and the bag-shaped container is characterized in that the cutting line acting on the tear strip is shortened by forming notches on one or both of the upper and lower edges in the width direction of the tear strip. [Effects of the Invention]

[0012] According to the bag-shaped container of the present invention, by forming a notch on one or both of the upper or lower edges of the tear strip at the position where the cutting line of the tear strip is formed, the cutting line is shortened, and by pulling up the gripping portion, the force is concentrated on this shortened cutting line, thereby causing interlayer delamination of the tear strip with less force. [Brief explanation of the drawing]

[0013] [Figure 1] (a) and (b) are diagrams illustrating the structure of the tear strips of a conventional bag-shaped container, and (c) is a diagram illustrating its usage. [Figure 2] (a) is an explanatory diagram illustrating the structure of the tear strip of a bag-shaped container according to the first embodiment of the present invention, and (b) is an explanatory diagram illustrating the method of use thereof. [Figure 3] A plan view illustrating the welded portion of the airtight sheet to the tear strip of the bag-shaped container according to the first embodiment. [Figure 4] (a) and (b) are plan views showing other shape variations of the notches formed in the tear strips. [Figure 5] A plan view showing other shape variations of the welded joint of the airtight sheet. [Modes for carrying out the invention]

[0014] (General structure of tear strips) An opening structure using a tear strip for a bag-shaped container will be explained with reference to Figure 1. Although not shown, the bag-shaped container 1 is formed by folding the left and right ends of a rectangular functional film to the back and joining them together using a method such as heat welding. Then, a cylindrical body is formed by overlapping the surface film and the back film, and the top and bottom ends are sealed to form the bag-shaped container 1 that stores contents inside (for the structure of the bag-shaped container, please refer to the conventional example described above, Japanese Patent Application Publication No. 2018-188196).

[0015] Here, a portion of the surface film 10 has a gas barrier layer that protects the contents of the bag-shaped container 1, such as food, from deterioration such as oxidation. This gas barrier layer is made by, for example, laminating aluminum foil into a film or coating the film surface of a substrate such as PET, stretched nylon (ONy), stretched polypropylene (OPP), or unstretched polypropylene (CPP) with silica or alumina, which can be formed into a transparent and extremely thin film, by vapor deposition.

[0016] As shown in Figures 1(a) and 1(b), the basic structure of the bag-shaped container that forms the basis of the present invention is constructed by attaching tear strips 11 to the back surface of the surface film 10 which constitutes the resin film, as described above. The bag-shaped container 1 is opened by pulling up the gripping portion 12 formed at the end of the tear strip 11 to tear the surface film 10.

[0017] As shown in Figures 1(a) and 1(b), the tear strip 11 is a long, flexible material made of a plastic such as polypropylene, having a predetermined thickness, and is placed between the surface film 10 that constitutes the bag-shaped container 1 and the zipper base 14, which integrates the tear strip 11 and a zipper tape (not shown) that seals and allows the opening opened by the tear strip 11 to be opened and closed.

[0018] Here, while the upper surface of the tear strip 11 is integrally welded to the surface film 10, the lower surface of the tear strip 11 is in a state of being pseudo-adhered to the zipper base 14 made of a polyethylene resin, and the structure is such that the two can be separated by applying force.

[0019] Also, as shown in Fig. 1(c), the gripping portion 12 cuts the surface film 10 and the zipper base 14 along an elliptical cutting line CL so as to surround the end portion 11a of the tear strip 11 (in the figure, the cutting line CL is shown as a thick line), and the user can roll up the surface film 10 of the bag-like container 1 by pinching the gripping portion 12 with a finger.

[0020] Here, a cutting line 13 is formed on the lower surface of the tear strip 11 near the gripping portion 12, which cuts across the width direction thereof, and a cut is formed from the surface to a predetermined depth so as to cut the zipper base 14 on the tear strip 11.

[0021] As shown in Fig. 1(a), when the gripping portion 12 pulls up the tear strip 11 beyond the cutting line 13, the zipper base 14 pseudo-adhered to the lower surface of the tear strip 11 remains on the surface film 10 side and delaminates from the tear strip 11 with the cutting line 13 as the boundary.

[0022] That is, as shown in Fig. 1(b), the zipper base end portion 14a on one side of the cutting line end portion 13a is pulled up together with the tear strip 11 as the gripping portion 12, while the zipper base body 14b on the other side of the cutting end portion 13b separates from the tear strip 11.

[0023] Then, as shown in Fig. 1(c), by further pulling up the tear strip 11, the surface film strip 10a adhered to the upper surface thereof is removed so as to tear it from the surface film body 10b, and an opening S of the bag-like container 1 is formed at this portion.

[0024] Furthermore, an airtight sheet 16 is attached to the back side of the gripping portion 12, surrounding it. As will be described later, the gripping portion 12 is formed by heat-welding this airtight sheet 16 to the back side of the surface film 10. Therefore, even if there are cuts in the surface film 10 due to the die-cut lines CL, the airtightness inside the bag-shaped container 1 is ensured.

[0025] (First Embodiment) A first embodiment of the present invention will be described with reference to Figures 2 and 3. Regarding the tear strip 11, gripping portion 12, and zipper base 14, parts that are unchanged from the basic conventional structure described above are denoted by the same reference numerals and their description is omitted.

[0026] As shown in Figure 2(a), the tear strip 11 of this embodiment has notches 15 (the upper one is called the upper edge notch 15a, and the lower one is called the lower edge notch 15b) formed at the position of the cutting line 13X, cutting out the upper and lower edges. These notches 15a and 15b are arc-shaped, and the cutting line 13X is formed at the position where they are closest to each other.

[0027] Then, as shown in Figure 2(b), when the user lifts the gripping portion 12, whose outline is formed by the die-cut line CL, and pulls up the tear strip 11, an opening S is formed in this portion.

[0028] When the gripping portion 12 is pulled up, the zipper base end 14a is also pulled up along with the tear strip 11, but beyond the cutting line 13X, the zipper base body 14b, which is pseudo-adhered to the back surface of the tear strip 11, peels off from the tear strip 11.

[0029] In this process, the surface film strip 10a attached to the upper surface of the tear strip 11 of the surface film 10 constituting the bag-shaped container 1 is torn away from the rest of the surface film body 10b, thereby opening the bag-shaped container 1. However, the delaminated zipper base body 14b remains on the surface film body 10b side.

[0030] Furthermore, if the tear strip 11 is pulled up further beyond the area of ​​the airtight sheet 16, the bag-shaped container 1 is opened laterally, and the airtight seal inside the bag-shaped container 1 is released. As mentioned above, a zipper tape (not shown) is fixed to the zipper base 14 parallel to the bottom of the tear strip 11, and the user can freely reseal and reopen the bag-shaped container 1 using this zipper tape.

[0031] In this embodiment, the neck portion of the gripping portion 12 of the tear strip 11 has an upper edge notch 15a and a lower edge notch 15b, and a cutting line 13X is formed between these notches 15a and 15b, making the length of the cutting line 13 shorter than that of the conventional cutting line 13. As a result, the user can delaminate the tear strip 11 from the zipper base 14 with less force.

[0032] In particular, in this embodiment, since the shape of the notches 15 is all arc-shaped, a tapered shape is formed on both sides of the cutting line 13X in a part of the tear strip 11, allowing the force applied from the gripping part 12 to be gradually concentrated on the cutting line 13X. By concentrating the force over a short length, delamination can be more reliably caused in the zipper base 14. Furthermore, stress concentration can be achieved even if the formation position of the cutting line 13X is slightly shifted in the left-right direction.

[0033] Using Figure 3, the welding structure of the airtight sheet 16 to the surface film 10 in this embodiment will be explained. As described above, the surface film 10 is cut by the die-cut line CL to form the gripping portion 12 of the tear strip 11. In order to maintain the airtightness of this portion, an airtight sheet 16, which has the same gas barrier performance as the surface film 10, is welded to the back surface of the surface film 10 so as to cover the gripping portion 12.

[0034] The airtight seal of the airtight sheet 16 is maintained by an annular welded portion H formed to surround the grip portion 12, thereby sealing the inside of the bag-shaped container 1. This welded portion H is formed by pressing a mold of a similar shape onto the airtight sheet 16 and heating it, thereby welding the surface of the airtight sheet 16 to the surface of the surface film 10.

[0035] In other words, in the airtight sheet 16, non-welded surfaces 18a(18) and 18b(18) are formed on the inside and outside, respectively, with the annular, band-shaped welded portion H in between.

[0036] Here, the welded portion H, at a position where it straddles the tear strip 11, forms an overhang Ha that extends inward from the frame-shaped welded portion H, i.e., towards the non-welded surface 18a side, thereby increasing the thickness of the annular portion. This is because the tear strip 11 is thicker than the surrounding surface film 10 and airtight sheet 16, and gaps are likely to occur at the step. In other words, in this portion, welded portions H and Ha are formed that have a longer distance in the longitudinal direction of the tear strip 11, thus preventing a lack of airtightness due to gaps. Furthermore, the inner edge of the overhang Ha of the welded portion H is positioned to coincide with the cutting line 13X, thereby ensuring more reliable delamination of the zipper base 14.

[0037] Furthermore, by positioning the welded portion H adjacent to the die-cutting line CL and the cutting line 13X, and on the outside thereof, it is possible to prevent loss of airtightness even if the gripping portion 12 unintentionally peels up and causes excessive cracking in the surface film 10.

[0038] As described above, with the bag-shaped container 1 of this embodiment, the cutting line 13X that causes delamination can be shortened by forming notches 15 on the upper and lower edges of the tear strip 11, thus reducing the force required to pull up the tear strip 11. Therefore, even young users with weak strength can smoothly open the bag-shaped container.

[0039] In particular, in this embodiment, the notches 15 (15a, 15b) formed on the edges of the tear strip 11 are both arc-shaped. As a result, the tapered shape leading to the cutting line 13X allows the force applied from the gripping portion 12 to be gradually concentrated on the cutting line 13X, making it possible to cause delamination in the zipper base 14 with less force. Furthermore, the tapered shape beyond that point allows this stress to be gradually dispersed, enabling continuous delamination.

[0040] (Variations of notches) Figures 4(a) and 4(b) illustrate the variations in the shape of the notches formed in the tear strips 11.

[0041] Unlike the notch 15 in the first embodiment, the notches 15c, 15c shown in Figure 4(a) have a straight outline. That is, they are cut out by V-shaped notches 15c, 15c on both sides of the upper and lower edges of the tear strip 11, and the cutting line 13Y is formed at the position where the two are closest to each other.

[0042] Depending on the shape of the notch 15, a tapered shape can be formed from both sides toward the cutting line 13Y, and when the gripping part 12 is held and pulled up, the stress can be concentrated on the short cutting line 13Y, similar to the notch 15 of the first embodiment, and then the force can be radiated in the opposite direction from the cutting line 13Y.

[0043] Unlike the notch 15 described above, the notch 15d shown in Figure 4(b) is formed in an arc shape only on the upper edge of the tear strip 11. Compared to the notch 15 of the first embodiment, the arc shape of the notch 15d is larger, and by scooping out a larger portion of the tear strip 11, the length of the cutting line 13Z formed in the middle can be shortened.

[0044] Furthermore, the notch 15d also allows for the formation of tapered shapes on both sides of the cutting line 13Z, enabling stress concentration and divergence before and after the cutting line 13Z.

[0045] Of course, the notch may be a simple U-shaped notch without a tapered shape, and in this way, the notch 15 for shortening the cutting line 13 can be selected from a variety of shapes and numbers.

[0046] (Variations of welded areas) Figure 5 illustrates the variations in the shape of the welded portion H.

[0047] In Figure 5, the welded portion H has a non-welded surface 18c in the center of the protruding portion Hb that straddles the tear strip 11. Therefore, in this variation, the protruding portion Hb is welded along its contour near the cutting line 13X, resulting in a shape that reduces the welded area while ensuring airtightness.

[0048] Although a predetermined amount of heat is required for the heat welding process, this structure allows for a reduction in the welding area, thereby shortening the heating time and providing a bag-shaped container 1 with superior manufacturing efficiency.

[0049] The welded portion H needs to surround the die-cut line CL that forms the outline of the gripping portion 12 in order to ensure airtightness by the airtight sheet 16, but its shape, especially the shape near the tear strip 11, can be selected from a variety of options. In addition, the protruding portions Ha and Hb may be formed to protrude outward from the frame-shaped welded portion H. [Explanation of symbols]

[0050] 1 Bag-shaped container 11 tear strip 12 Grip part 13, 13X, 13Y, 13Z cutting line 14 Zipper Base 15, 15a, 15b, 15c, 15d notch 16. Airtight sheet 18(18a, 18b, 18c) Non-weld surface CL cutout line H Welded area Ha, Hb overhang

Claims

1. It is formed by a bag body that forms a storage space by folding or overlapping rectangular film, and a long tear strip fixed to the inside of the bag body and a zipper base laminated on its lower surface, A cutting line surrounding one end of the tear strip forms a gripping portion of the tear strip, and adjacent to the gripping portion, a cutting line is formed that crosses the zipper base in the width direction of the tear strip. In a bag-shaped container in which the user lifts the gripping portion, the tear strip and the zipper base delaminate along the cutting line, and the base material layer of the tear strip cuts through the bag body, thereby opening the bag, A bag-shaped container characterized in that the cutting line acting on the tear strip is shortened by forming notches on one or both of the upper and lower edges in the width direction of the tear strip.

2. A bag-shaped container according to claim 1, The bag-shaped container is characterized in that the notches are formed in two on both sides of the cutting line and are arc-shaped and close to each other.

3. A bag-shaped container according to claim 1 or 2, The back surface of the bag body has an airtight sheet fixed by a heat-sealed welded portion that surrounds the entire circumference of the gripping portion, thereby ensuring airtightness inside the bag body, A bag-shaped container characterized in that the welded portion has a protruding portion in the part that crosses the tear strip.

4. A bag-shaped container according to claim 4, The aforementioned welded portion is characterized in that a non-welded surface is formed on the inside of the protruding portion, forming a bag-shaped container.

Images