Zipper tape and container with zipper tape
Patent Information
- Application Number
- JP2022120630
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-07-28
- Publication Date
- 2025-08-05
AI Technical Summary
Existing zipper tapes face issues with unjoined portions at the ends of the opening, leading to potential peeling and leakage due to lower bonding strength between the resin forming the base strip and the bag main body.
A zipper tape design featuring a first and second member with engaging portions and thick wall portions, where the thick portions are covered by a sealing layer, ensuring strong bonding with the base film.
The sealing layer enhances the bonding strength between the thick portions and the base film, preventing unjoined portions and leakage, thus maintaining the integrity of the packaging.
Smart Images
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Abstract
Description
[Technical field]
[0001] The present invention relates to a zipper tape and a container with the zipper tape. [Background technology]
[0002] As a packaging material for packaging various items such as food, medicine, medical supplies, and miscellaneous goods, a packaging bag with zipper tape is used, in which a pair of strip-shaped zipper tapes formed of male and female members that interlock with each other are arranged at the opening of the bag, and the interlocking state can be opened and closed freely. Such a packaging bag with zipper tape is sealed by sealing the upper part of the zipper tape. A packaging bag has been proposed in which a protrusion is provided near the opening to make it easier for fingers to catch when opening.
[0003] As an example of such technology, Patent Document 1 discloses a packaging bag in which thick parts such as protrusions that function as anti-slip means for fingers when opening and closing the bag are provided along the edge of the zipper tape that opens, closes and seals the bag body, and the protrusions are disposed inside the opening of the bag body together with the zipper tape. By positioning the protrusions inside the bag body in this way, the anti-slip structure does not protrude significantly outside the bag, and the zipper tape and the entire bag can be made smaller. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Patent No. 4423045 Summary of the Invention [Problem to be solved by the invention]
[0005] However, in the technology disclosed in Patent Document 1, the resin forming the base strip has a low bonding strength relative to the resin forming the bag body, so when the zipper tape is heat-sealed to the bag body, there is a risk that unbonded portions will remain at the protrusions on both ends of the bag opening. If unbonded portions remain, the base strip may peel off from the bag body, causing the internal pressure of the bag to leak, resulting in problems such as leakage of the packaged contents and damage to the appearance of the molded product.
[0006] Therefore, an object of the present invention is to provide a zipper tape and a container with a zipper tape that can prevent the occurrence of unjoined portions at both ends of the opening. [Means for solving the problem]
[0007] [1] A zipper tape having a first member and a second member opposed to each other, each of the first member and the second member including a base strip, a first resin portion including an engaging portion protruding from opposing sides of the base strip and engageable with each other, a second resin portion laminated on at least a part of the side of the base strip opposite the engaging portion, and a thick portion formed on an end of the base strip in the width direction, wherein at least a part of the thick portion continuing from the side of the base strip opposite the engaging portion of the first member is the second resin portion. [2] The zipper tape according to [1], wherein at least a portion of the surface of the thick portion of the first component is covered with the second resin portion. [3] The zipper tape according to [1] or [2], wherein the thick portion of the first component is entirely formed from the second resin portion. [4] The zipper tape according to any one of [1] to [3], wherein the thick portions of the first and second members are arranged in staggered positions in the width direction of the base strip when the engaging portions are engaged with each other. [5] The zipper tape according to [4], wherein the thick portion of the first member is positioned in a position that protrudes toward the widthwise end of the base strip more than the thick portion of the second member when the engaging portions are engaged with each other. [6] A container with zipper tape comprising: the zipper tape according to any one of [1] to [5]; a base film forming a storage space inside and having a first side and a second side facing each other with the storage space therebetween; and a container body in which the first member of the zipper tape is fused to the base film on the first side and the second member of the zipper tape is fused to the base film on the second side. [7] The container with zipper tape described in [6], wherein the thick portions of the first member and the second member are not fused to each other in areas other than the side seal area where the first surface and the second surface are joined to each other. [8] A container with a zipper tape described in [6] or [7], wherein the container body forms a bag body. Effect of the Invention
[0008] According to the zipper tape and the container with the zipper tape of the present invention, a seal layer is formed between the thick portion formed on at least one of the opposing portions and the base film, which increases the bonding strength between the thick portion and the base film and thus suppresses the occurrence of unbonded portions at both ends of the opening. [Brief description of the drawings]
[0009] [Figure 1] 1 is a front view showing a zipper tape bag according to one embodiment of the present invention. FIG. [Figure 2A] 2 is a cross-sectional view taken along line IIA-IIA of the bag with zipper tape shown in FIG. 1. [Figure 2B] 2 is a cross-sectional view of the side seal portion of the zipper tape bag shown in FIG. 1 taken along line IIB-IIB. [Figure 3A] FIG. 4 is a diagram showing a second example of a thick portion formed in the zipper tape in one embodiment of the present invention. [Figure 3B] 3B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 3A. [Figure 4A] FIG. 11 is a diagram showing a third example of a thick portion formed in a zipper tape according to one embodiment of the present invention. [Figure 4B] 4B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 4A. [Figure 5A] FIG. 11 is a diagram showing a fourth example of a thick portion formed in a zipper tape according to one embodiment of the present invention. [Figure 5B] 5B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 5A. [Figure 6A] FIG. 11 is a diagram showing a fifth example of a thick portion formed in a zipper tape in one embodiment of the present invention. [Figure 6B] 6B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 6A. [Figure 7A] FIG. 10 is a diagram showing a sixth example of a thick portion formed in a zipper tape according to one embodiment of the present invention. [Figure 7B] 7B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 7A. [Figure 8A] FIG. 13 is a diagram showing a seventh example of a thick portion formed in a zipper tape in one embodiment of the present invention. [Figure 8B] 8B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 8A. [Figure 9A] FIG. 13 is a diagram showing a thick portion formed in a zipper tape of a conventional example. [Figure 9B] 9B is a cross-sectional view of a side seal portion of the zipper tape of the example of FIG. 9A. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0010] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.
[0011] In this specification, the main component of the resin composition forming each layer of the laminate means the resin component with the highest content among the resin compositions forming that layer. Therefore, the resin composition may contain other components in addition to the main component. The main component can be confirmed, for example, by an IR method. In this specification, the content of the component of the resin composition forming each layer of the laminate is expressed in mass% relative to the entire resin composition forming that layer, unless otherwise specified.
[0012] In this specification, the main polymer means the component that is the most abundant among the components constituting each layer, and when each layer is composed of n components (n is an integer of 2 or more), the main polymer means a component that is contained in an amount of 100 / n% or more, preferably 100 / n x 1.2 times % or more. The main polymer can be analyzed by infrared spectroscopy, NMR, DSC, etc. It is to be noted that impurities may be contained within a range that does not impair the effects of the present invention.
[0013] Fig. 1 is a front view of a bag with zipper tape 1 according to one embodiment of the present invention, and Fig. 2A is a cross-sectional view taken along line IIA-IIA of the bag with zipper tape 1 shown in Fig. 1. Fig. 2B is a cross-sectional view of a side seal portion taken along line IIB-IIB of the bag with zipper tape 1 shown in Fig. 1. As shown in Figs. 1 and 2A, the bag with zipper tape 1 is a container with zipper tape including a base film 10 forming a bag body, which is a container main body having a first surface 11A and a second surface 11B, and a zipper tape 20.
[0014] The base film 10 is formed of, for example, a single-layer or multi-layer thermoplastic resin. More specifically, the base film 10 may include a layer formed of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or polypropylene (PP). PP may be homopolypropylene (HPP), random polypropylene (RPP), or block polypropylene (BPP). When the base film 10 is multi-layered, biaxially oriented polypropylene (OPP), biaxially oriented polyethylene terephthalate (OPET), or biaxially oriented nylon (ONy) may be used for the front substrate. These are not limited to resins derived from fossil fuels, and may be environmentally friendly bioplastics (polyolefin resins such as biopolyethylene and biopolypropylene derived from biomass), or may be a mixture of a resin derived from fossil fuels and a bioplastic. The base film 10 may also include a layer of an inorganic material formed by aluminum deposition, lamination of aluminum foil, or the like.
[0015] In this embodiment, two base films 10 are joined together at the bottom seal portion 12 and the side seal portion 13 to form a storage space inside, and a bag body having a first surface 11A and a second surface 11B facing each other with the storage space therebetween is formed. In another embodiment, the first surface 11A and the second surface 11B may be formed by folding back one base film 10 at a portion corresponding to the side seal portion 13. Alternatively, a portion where the base film 10 is folded inward, that is, a so-called gusset, may be formed at a portion corresponding to the bottom seal portion 12 or the side seal portion 13 in the example of FIG. 1. In this case, the gusset may be formed by the base film 10 or by another film joined to the base film 10. The bag 1 with the zipper tape may be a standing pouch that can be placed upright by forming a gusset at the bottom.
[0016] In this embodiment, the bottom seal portion 12 and the side seal portion 13 are formed, while the top seal portion is not formed, thereby forming the opening 14 of the bag with zipper tape 1. In another embodiment, the top seal portion may be formed in addition to the bottom seal portion 12 and the side seal portion 13, and the opening 14 may be formed in the bag with zipper tape 1 afterwards by cutting between the top seal portion and the zipper tape 20. In yet another embodiment, the bag body may be provided in a state in which the bottom seal portion 12 is not formed, that is, the bag with zipper tape 1 is not sealed on the side opposite to the zipper tape 20. In this case, the bottom seal portion 12 is formed after the bag with zipper tape 1 is filled with the contents. In addition to this, the present invention can be applied to bags of various known configurations and containers other than bags, as long as the zipper tape 20 is fused.
[0017] As shown in FIG. 2A, the zipper tape 20 includes a first member 20A fused to the first surface 11A of the base film 10 and a second member 20B fused to the second surface 11B. The zipper tape 20 is formed of, for example, a polyolefin resin. More specifically, the zipper tape 20 may be formed of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), or polypropylene (PP). PP may be homopolypropylene (HPP), random polypropylene (RPP), or block polypropylene (BPP). From the viewpoint of heat resistance and hardness, polypropylene (PP) is preferable. The polyolefin resin is not limited to a resin derived from fossil fuels, and may be an environmentally friendly bioplastic (a polyolefin resin such as biopolyethylene or biopolypropylene derived from biomass), or may be a mixture of a resin derived from fossil fuels and a bioplastic. If necessary, known additives such as stabilizers, antioxidants, lubricants, antistatic agents, colorants, and the like may be added to the material of the zipper tape 20.
[0018] Each of the first member 20A and the second member 20B includes a polyolefin portion 21A, 21B, which is a first resin portion formed of a resin composition containing polyolefin as a main polymer, a sealing layer 22A, 22B, which is a second resin portion, and a thick portion 23A, 23B. The polyolefin portion 21A, 21B includes a base strip 211A, 211B and an engagement portion 212A, 212B, which protrudes from the opposing surfaces of the base strip 211A, 211B. The sealing layer 22A, 22B is located between the polyolefin portion 21A, 21B and the first surface 11A and the second surface 11B of the base film 10, and bonds these portions to each other. The thick portion 23A, 23B is formed at the end of the base strip 211A, 211B on the opening 14 side in the width direction.
[0019] The engaging parts 212A and 212B protrude from the opposing surfaces of the base strips 211A and 211B, respectively, and are engageable with each other. In the example shown in FIG. 2A, the engaging part 212A has a female cross-sectional shape, and the engaging part 212B has a male cross-sectional shape. The zipper tape 20 is closed by engaging the engaging parts 212A and 212B with each other, and the opening 14 of the bag 1 with the zipper tape is sealed. The shapes of the engaging parts 212A and 212B of the zipper tape 20 are not limited to male and female shapes, and it is also possible to apply the shapes of the engaging parts 212A and 212B of various known zipper tapes 20 that combine claw shapes, hook shapes, knob shapes, etc. to the engaging parts 212A and 212B of the above example. In either case, the engaging parts 212A and 212B are irregularly shaped parts protruding from the base strips 211A and 211B having a substantially rectangular cross section. In order to maintain the shape of such irregular portions and reliably seal the opening 14 when the engaging portions 212A, 212B engage, and to provide a suitable opening sensation when the engaging portions are released, it is advantageous to form the engaging portions 212A, 212B in the polyolefin portions 21A, 21B which have polyolefin as the main polymer.
[0020] The raw material of the seal layers 22A and 22B preferably contains, for example, linear low-density polyethylene (metallocene linear low-density polyethylene) obtained using a metallocene catalyst, and more preferably contains linear low-density polyethylene obtained using a metallocene catalyst and a propylene-α-olefin copolymer obtained using a metallocene catalyst. The zipper tape 20 is formed, for example, by co-extrusion molding the resins of each part. The raw material of the seal layers 22A and 22B contains, for example, the following resin (A) at 5% by mass or more, preferably 10% by mass or more, and 50% by mass or less, preferably 40% by mass or less. The raw material also contains the following resin (B) at 50% by mass or more, preferably 60% by mass or more, and 95% by mass or less, preferably 90% by mass or less. Furthermore, it is preferable to use a resin composition having a maximum peak at a scattering angle of 14°±0.5° in wide-angle X-ray scattering by X-ray diffraction. Resin (A): Density 900kg / m 3 The following is a propylene-α-olefin copolymer obtained using a metallocene catalyst having a melt flow rate (MFR) of 1.0 g / 10 min to 20 g / 10 min and a melting point of 100° C. or less. Resin (B): Density 900kg / m 3 Linear low-density polyethylene obtained using a metallocene catalyst having an MFR of 1.0 g / 10 min or more and 20 g / 10 min or less and a melting point of 80°C or more and 100°C or less.
[0021] The thick portions 23A and 23B may be spherical as shown in the figure, but may also be convex stripes having a cross section of an angular shape such as a square or rhombus. For example, the thick portion 23A may be spherical and the thick portion 23B may be square, or the thick portion 23A may be rhombus and the thick portion 23B may be spherical. The shapes of the thick portions 23A and 23B may also be a combination of different cross sections. In the example of FIG. 2A, the thick portions 23A and 23B are arranged so as to face each other at the same position in the width direction of the base strips 211A and 211B when the engaging portions 212A and 212B are engaged with each other. The thick portions 23A and 23B catch the fingers at the end on the opening 14 side when the bag 1 with the zipper tape is opened or closed, and thus serve as a means for preventing the fingers from slipping when the bag is opened or closed.
[0022] Of the two thick portions 23A, 23B, at least the thick portion 23A on the first member 20A side is at least partially a sealing layer 22A that continues to the surface of the base strip 211A opposite to the engaging portion 212A. In the illustrated example, the sealing layer 22A is formed between the thick portion 23A and the first surface 11A of the substrate film 10. The thick portion 23B on the second member 20B side is formed of a polyolefin portion 21B.
[0023] 2A, the thick portions 23A, 23B have a protruding width W1 toward the base film 10 side and toward the opposite side to the base film 10 of preferably 0.1 mm or more, more preferably 0.2 mm or more. The thickness of the sealing layers 22A, 22B is preferably 5 μm or more, more preferably 10 μm or more. There is no particular upper limit, but it is, for example, 1 mm.
[0024] 2B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 in which the polyolefin portion 21A of the first member 20A and the polyolefin portion 21B of the second member 20B are joined, and the seal layer 22 in which the seal layer 22A of the first member 20A and the seal layer 22B of the second member 20B are joined, is joined to the base film 10 so as to be sandwiched between them. Since the seal layer 22A is formed between the thick portion 23A and the first surface 11A of the base film 10, the base film 10 and the polyolefin portion 21 are joined via the seal layer 22 on the first member 20A side.
[0025] Here, the thick part formed in the zipper tape of the conventional example will be described with reference to Fig. 9A. In the illustrated example, the bag 9 with zipper tape is a container with zipper tape including a base film 80 forming a bag body, which is a container body having a first surface 81A and a second surface 81B, and a zipper tape 90. The bag 9 with zipper tape is formed by two base films 80 forming a bag body having a first surface 81A and a second surface 81B facing each other, and an opening 84 of the bag 9 with zipper tape is formed. The zipper tape 90 includes a first member 90A fused to the first surface 81A of the base film 80 and a second member 90B fused to the second surface 81B.
[0026] Each of the first member 90A and the second member 90B includes a polyolefin portion 91A, 91B, which is a first resin portion formed of a resin composition containing polyolefin as a main polymer, a sealing layer 92A, 92B, which is a second resin portion, and a thick portion 93A, 93B. The polyolefin portion 91A, 91B includes a base strip 911A, 911B and an engagement portion 912A, 912B, which protrudes from the opposing surfaces of the base strip 911A, 911B. The sealing layer 92A, 92B is located between the polyolefin portion 91A, 91B and the first surface 81A and the second surface 81B of the base film 80, and bonds these portions to each other. The thick portion 93A, 93B is formed at the end of the base strip 911A, 911B on the opening 84 side in the width direction. The engagement portions 912A, 912B protrude from opposing surfaces of the base strips 911A, 911B, respectively, and are engageable with each other.
[0027] 9B is a cross-sectional view of the side seal portion of the zipper tape 90 of the example of FIG. 9A. As shown in the figure, in the side seal portion, the zipper tape 90 including the polyolefin portion 91 in which the polyolefin portion 91A of the first member 90A and the polyolefin portion 91B of the second member 90B are joined, and the seal layer 92 in which the seal layer 92A of the first member 90A and the seal layer 92B of the second member 90B are joined, is sandwiched and joined to the base film 80. In the zipper tape 90 of the conventional example, the base film 80 and the polyolefin portion 91 are joined in the portions shown in the regions L1 and L2 in the side seal portion. Since the resin forming the polyolefin portion 91 has a low bonding strength with respect to the resin forming the base film 80, there is a risk that the zipper tape 90 will become an unjoined portion when heat-sealing the zipper tape 90 to the bag body. If unjoined portions remain, the zipper tape 90 may peel off from the base film 80, causing the internal pressure of the bag to leak, resulting in problems such as leakage of the packaged contents and damage to the appearance of the molded product.
[0028] In contrast, in the bag 1 with zipper tape according to the present embodiment, as shown in Fig. 2A, a seal layer 22A is formed between the thick portion 23A and the first surface 11A of the base film 10, thereby increasing the bonding strength between the thick portion 23A and the first surface 11A of the base film 10. This is because, as shown in Fig. 2B, in the bag 1 with zipper tape according to the present embodiment, the base film 10 and the polyolefin portion 21 are bonded to the first member 20A side in the side seal portion 13 via a seal layer 22. Therefore, when the zipper tape 20 is fused to the bag body, the occurrence of unbonded portions can be suppressed in the portions where the longitudinal ends of the thick portions 23A and 23B intersect with the side seal portion 13, which are both ends of the opening 14.
[0029] Examples of the two thick portions 23A, 23B are not limited to those shown in FIG. 2A. Other examples of the thick portions 23A, 23B are shown below. In FIGS. 3A, 4A, 5A, 6A, 7A, and 8A, similar to the example shown in FIG. 2A, the zipper tape 20 is composed of a first member 20A fused to the first surface 11A of the base film 10 and a second member 20B fused to the second surface 11B. Each of the first member 20A and the second member 20B includes polyolefin portions 21A, 21B formed of a resin composition having polyolefin as a main polymer, seal layers 22A, 22B, and thick portions 23A, 23B. The polyolefin portions 21A, 21B include base strips 211A, 211B and engagement portions 212A, 212B protruding from opposing faces of the base strips 211A, 211B. The engagement portions 212A, 212B are engageable with each other. The sealing layers 22A, 22B are located between the polyolefin portions 21A, 21B and the two substrate films 10, and bond these portions to each other. The thick portions 23A, 23B are formed at the ends of the base strips 211A, 211B on the opening 14 side in the width direction.
[0030] In the second to fourth examples of the thick portions 23A, 23B shown in Figures 3A, 4A and 5A, similar to Figure 2A, the thick portions 23A, 23B are arranged to face each other at the same position in the width direction of the base strips 211A, 211B when the engagement portions 212A, 212B are engaged with each other.
[0031] In a second example of thick portions 23A, 23B shown in FIG. 3A, in addition to the first member 20A fused to the first surface 11A of the base film 10, a sealing layer 22B is also formed between the thick portion 23B and the second surface 11B of the base film 10 in the second member 20B fused to the second surface 11B.
[0032] FIG. 3B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 of the example of FIG. 3A. As shown in FIG. 3B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is bonded to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are bonded to both the first member 20A side and the second member 20B side via the seal layer 22. Therefore, according to the illustrated configuration, the bonding strength between the thick portion 23A on the first member 20A side and the first surface 11A of the base film 10 can be increased, and the bonding strength between the thick portion 23B on the second member 20B side and the second surface 11B of the base film 10 can be increased. Therefore, when the zipper tape 20 is fused to the bag body, the occurrence of unbonded portions can be further suppressed at the portions where the longitudinal ends of the thick portions 23A and 23B, which are both ends of the opening 14, intersect with the side seal portion 13.
[0033] In a third example of thick portions 23A, 23B shown in Fig. 4A, the surface of thick portion 23A on the first member 20A side is covered with seal layer 22A, and the inside of spherical thick portion 23A is formed of polyolefin portion 21 A. In the illustrated example, thick portion 23B on the second member 20B side is formed of polyolefin portion 21B, but this is not limiting, and thick portion 23B may also have an inside formed of polyolefin portion 21B and a surface covered with seal layer 22A.
[0034] Fig. 4B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 of the example of Fig. 4A. As shown in Fig. 4B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is joined to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are joined via the seal layer 22 on the first member 20A side. Therefore, according to the illustrated configuration, the joining strength is further increased at the portions where the longitudinal ends of the thick portions 23A, 23B and the side seal portion 13 intersect, and the occurrence of unjoined portions can be suppressed.
[0035] 5A, the entire thick portion 23A on the first member 20A side is formed of the seal layer 22A. In the illustrated example, the thick portion 23B on the second member 20B side is formed of the polyolefin portion 21B, but this is not limiting, and the entire thick portion 23B may also be formed of the seal layer 22B.
[0036] Fig. 5B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 of the example of Fig. 5A. As shown in Fig. 5B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is joined to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are joined via the seal layer 22 on the first member 20A side and part of the opening 14 side. Therefore, according to the illustrated configuration, the joining strength is further increased at the portions where the longitudinal ends of the thick portions 23A, 23B and the side seal portion 13 intersect, and the occurrence of unjoined portions can be suppressed.
[0037] In the fifth to seventh examples of the thick-walled portions 23A and 23B shown in Figs. 6A, 7A, and 8A, which will be described below, when the engagement portions 212A and 212B are engaged with each other, the thick-walled portion 23A is disposed at a position protruding toward the end of the opening 14 in the width direction of the base strips 211A and 211B more than the thick-walled portion 23B. The thick-walled portion 23A may protrude from the thick-walled portion 23B. The protruding width D between the end edge of the thick-walled portion 23A and the end edge of the thick-walled portion 23B shown in Fig. 6A is preferably 0.5 mm or more, more preferably 1.0 mm or more. The protruding width D is not particularly limited, but is, for example, 1 cm or less. The width W2 of the thick-walled portions 23A and 23B is preferably 0.3 mm or more, more preferably 0.5 mm or more. The width W2 of the thick-walled portions 23A and 23B is preferably 5.0 mm or less, more preferably 3.0 mm or less. The protruding width D and the width W2 of the thick portions 23A and 23B are not limited to these.
[0038] In a fifth example of the thick portions 23A and 23B shown in Fig. 6A, a seal layer 22A is formed between the thick portion 23A and the first surface 11A of the base film 10, similarly to the case shown in Fig. 2A. In addition to this, although not shown, a seal layer 22B may also be formed between the thick portion 23B and the second surface 11B of the base film 10 in the second member 20B fused to the second surface 11B.
[0039] FIG. 6B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 of the example of FIG. 6A. As shown in FIG. 6B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is bonded to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are bonded to the first member 20A side via the seal layer 22. Therefore, according to the illustrated configuration, the occurrence of unbonded portions is suppressed at the portions where the longitudinal ends of the thick portions 23A, 23B and the side seal portion 13 intersect. In addition, by arranging the thick portions 23A, 23B at alternate positions in the width direction of the base strips 211A, 211B, the opposing thick portions 23A, 23B do not interfere with each other, and it becomes easy to insert fingers between the thick portions 23A, 23B when opening a bag. Therefore, the illustrated thick portions 23A, 23B can ensure both a means for preventing fingers from slipping when opening and closing a bag and easy insertion of fingers.
[0040] In a sixth example of the thick portions 23A, 23B shown in Fig. 7A, the surface of the thick portion 23A on the first member 20A side is covered with the seal layer 22A, similarly to the case shown in Fig. 4A. In the illustrated example, the thick portion 23B on the second member 20B side is formed of the polyolefin portion 21B, but this is not limiting, and the thick portion 23B may also be internally formed of the polyolefin portion 21B and the surface covered with the seal layer 22A.
[0041] 7B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 in the example of FIG. 7A. As shown in FIG. 7B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is joined to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are joined via the seal layer 22 on the first member 20A side, the opening 14 side, and a part of the second member 20B side. Therefore, according to the illustrated configuration, as in the example of FIG. 6A, the occurrence of unjoined portions is suppressed at the portions where the longitudinal ends of the thick portions 23A and 23B intersect with the side seal portion 13, and both the slip prevention means for fingers when opening and closing a bag and the ease of insertion of fingers can be ensured.
[0042] In a seventh example of the thick portions 23A, 23B shown in Fig. 8A, the entire thick portion 23A is formed of the seal layer 22A, similarly to the case shown in Fig. 5A. In the illustrated example, the thick portion 23B on the second member 20B side is formed of the polyolefin portion 21B, but this is not limiting, and the entire thick portion 23B may also be formed of the seal layer 22B.
[0043] Fig. 8B is a cross-sectional view of the side seal portion 13 of the zipper tape 20 of the example of Fig. 8A. As shown in Fig. 8B, in the side seal portion 13, the zipper tape 20 including the polyolefin portion 21 and the seal layer 22 is joined to the base film 10 so as to be sandwiched therebetween. The base film 10 and the polyolefin portion 21 are joined via the seal layer 22 on the first member 20A side and the opening 14 side. Therefore, according to the illustrated configuration, as in the example of Fig. 6A, the occurrence of unjoined portions is suppressed at the portions where the longitudinal ends of the thick portions 23A, 23B intersect with the side seal portion 13, and both the slip prevention means for fingers when opening and closing the bag and the ease of insertion of fingers can be ensured.
[0044] The arrangement of the thick portions 23A, 23B is not limited to the above example. The thick portion 23B may be arranged at a position that protrudes further toward the end of the opening 14 in the width direction of the base strips 211A, 211B than the thick portion 23A when the engagement portions 212A, 212B are engaged with each other. Furthermore, a plurality of the thick portions 23A, 23B may be arranged on the end side of the opening 14 in the width direction of the base strips 211A, 211B.
[0045] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art in the technical field to which the present invention pertains can come up with various modified or altered examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Explanation of symbols]
[0046] 1: Bag with zipper tape 10: Base film 11A: First surface 11B: Second surface 13: Side seal portion 14: Opening 20: Zipper tape 20A: First member 20B: Second member 21, 21A, 21B: Polyolefin portion 22, 22A, 22B: Seal layer 23A, 23B: Thick portion 211A, 211B: Base strip 212A, 212B: Engagement portion
Claims
1. A zipper tape having opposing first and second members, Each of the first member and the second member comprises: a first resin portion including a base strip and engaging portions protruding from opposing surfaces of the base strip and capable of engaging with each other; a second resin portion laminated on at least a portion of the surface of the base strip opposite the engaging portion; a thickened portion formed at an end portion in the width direction of the base strip; Including, In the zipper tape, at least a part of the thickened portion of the first member, which is continuous with the surface of the base strip opposite to the engaging portion, is made of the second resin portion.
2. At least a part of the surface of the thick portion of the first member is covered with the second resin portion. The zipper tape of claim 1 .
3. the thick portion of the first member is entirely formed of the second resin portion; The zipper tape of claim 1 .
4. the thickened portions of the first member and the second member are arranged at alternate positions in the width direction of the base strip when the engaging portions are engaged with each other; The zipper tape of claim 1 .
5. the thick portion of the first member is disposed at a position that protrudes toward an end of the base strip in the width direction relative to the thick portion of the second member when the engaging portions are engaged with each other; The zipper tape according to claim 4.
6. The zipper tape according to any one of claims 1 to 5; a base film that forms a storage space inside and has a first surface and a second surface that face each other with the storage space therebetween; a container body in which the first member of the zipper tape is fused to the base film on the first surface and the second member of the zipper tape is fused to the base film on the second surface; A container with a zipper tape.
7. the thick portions of the first member and the second member are not fused to each other in a region other than a side seal region where the first surface and the second surface are joined to each other; The container with zipper tape according to claim 6.
8. The container body forms a bag. The container with zipper tape according to claim 6.