Container with zipper tape and zipper tape

Abstract

Provided is a container provided with a zipper tape comprising a first base part, a tear strip, a second base part, a first engagement part, a second engagement part, and an easy peel layer which is formed on a first-base-part-side surface of the second base part that extends further than the first base part, wherein: the first base part is bonded to a film with first bonding parts formed on a surface of the first base part that is opposite from the first engagement part; the first bonding parts and non-bonding parts or weak bonding parts which extend across the first base part in the width direction are alternately disposed in the length direction of the first base part; the second base part is bonded to a film with a second bonding part which is formed on a portion of the second base part that extends further than the tear strip on a first side and a third bonding part which is formed on the easy peel layer; and the second bonding part and the third bonding part are each continuously formed in the length direction.

Description

Container with zipper tape and zipper tape

[0001] The present invention relates to a container with a zipper tape and a zipper tape.

[0002] For example, in containers with zipper tape that are distributed filled with contents, technologies have been proposed to prevent the contents from adhering to the zipper before opening. For example, Patent Document 1 describes a retort pouch in which a zipper for resealing a cooking liquid is heat-sealed to the inside of the upper part of a side film, and an easy-peel part is provided continuous with the zipper to further seal in the cooking liquid and prevent the cooking liquid from adhering to the zipper. The zipper is formed with a non-sealed part that allows steam to pass through, and hot air can be discharged from inside the retort pouch when the contents are heated.

[0003] On the other hand, for example, Patent Document 2 describes a bag in which both zipper tape components are joined to one side of the container body, so that contents can be filled without passing through the zipper before the top seal is formed. After the top seal is formed, an opening leading to the zipper is formed by pulling a tear guide provided on one side of the container body, and contents can be inserted or removed through this opening, and the container can be sealed and re-opened by the zipper.

[0004] Patent No. 6139086 International Publication No. 2023 / 080078

[0005] The container described in Patent Document 1 has zipper bases fixed to both sides of a retort pouch, and filling with cooking liquid requires the zipper to be opened. Therefore, if the zipper is initially attached in a closed state, a complicated procedure is required: open the zipper, fill with cooking liquid, close the zipper, and then heat-seal the easy-peel portion. In contrast, the container described in Patent Document 2 has a simpler procedure, since the contents can be filled with the zipper closed and then the top seal portion is formed. However, the container described in Patent Document 2 does not have a mechanism for venting steam when the contents are heated, and there is no knowledge of how to apply such a mechanism.

[0006] Therefore, an object of the present invention is to provide a container with zipper tape and zipper tape that can prevent the contents from sticking to the zipper before opening, can be filled with contents without opening the zipper, and can also allow steam to be released when heated.

[0007] [1] A container with zipper tape, in which zipper tape is attached to a film forming a container body, the zipper tape comprising: a first base; a tear strip disposed on a first side in the width direction of the first base; a second base including a portion extending beyond the tear strip on the first side and extending beyond the first base on a second side opposite the first side; a first engaging portion and a second engaging portion projecting from the first base and the second base, respectively, and engageable with each other; and a second engaging portion formed on a surface of the second base facing the first base, the second engaging portion extending beyond the first base on the second side. and an easy-peel layer, wherein the first base is joined to the film at a first joint portion formed on a surface opposite to the first engaging portion, the first joint portion alternating with non-joined or weakly joined portions extending across the width of the first base in the longitudinal direction of the first base, and the second base is joined to the film at a second joint portion formed on the first side in a portion extending beyond the tear strip and a third joint portion formed on the easy-peel layer, the second and third joint portions being continuous along the longitudinal direction. [2] The container with zipper tape according to [1], wherein the non-joined portions or weakly joined portions include a first non-joined or weakly joined portion formed continuously along the longitudinal direction of a portion of the first base in the width direction, and second non-joined or weakly joined portions alternating with the first joint portions along the longitudinal direction of the remaining portion of the first base in the width direction. [3] The zipper tape-equipped container according to [1] or [2], wherein the tear strip is formed continuously with the first base and is joined to the film at a fourth joint formed continuously in the length direction.[4] A zipper tape comprising: a first base; a tear strip disposed on a first side in the width direction of the first base; a second base including a portion extending beyond the tear strip on the first side and extending beyond the first base on a second side opposite the first side; first and second engaging portions projecting from the first and second bases, respectively, and engageable with each other; and an easy-peel layer formed on a surface of the second base extending beyond the first base on the second side, the surface of the first base facing the first base, the second engaging portion extending beyond the first base on the second side; wherein non-bonded or weakly bonded portions are formed on the surface of the first base opposite the first engaging portion, the non-bonded or weakly bonded portions being alternately arranged with bonded portions in the length direction of the first base and extending across the first base in the width direction. [5] The zipper tape according to [4], wherein the non-bonded or weakly bonded portions include first non-bonded or weakly bonded portions formed continuously in the length direction along a portion of the width direction of the first base, and second non-bonded or weakly bonded portions formed alternately with the bonded portions along the length direction along the remaining portion of the width direction of the first base. [6] The zipper tape according to [4] or [5], wherein the tear strip is formed continuously with the first base, and the non-bonded or weakly bonded portions are not formed along at least a portion of the width direction of the tear strip.

[0008] According to the above configuration, by joining the first base and the second base to the same surface of the container body, it is possible to fill the container with contents without opening the zipper. Furthermore, by joining the easy-peel layer formed on the first base side of the second base to the same surface of the container body as the first base, it is possible to prevent the contents from adhering to the zipper before opening. Furthermore, by forming a non-bonded or weakly bonded portion across the width of the surface of the first base opposite the first engaging portion, it is possible to release steam during heating.

[0009] 1 is a plan view of a container with zipper tape according to one embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1. FIG. 3 is a view showing a state of the container with zipper tape shown in FIG. 1 when contents are sealed therein. FIG. 4 is a view showing a state of the container with zipper tape shown in FIG. 1 when opened. FIG. 5 is a view for explaining in more detail the bonding state between the zipper tape and a film in the container with zipper tape shown in FIG. 1. FIG. 6 is a view for explaining in more detail the bonding state between the zipper tape and a film in the container with zipper tape shown in FIG. 1. FIG. 7 is a cross-sectional view showing an example of a zipper tape according to an embodiment of the present invention. FIG. 8 is a cross-sectional view showing a modified example of the zipper tape according to an embodiment of the present invention. FIG. 9 is a cross-sectional view showing another modified example of the zipper tape according to an embodiment of the present invention. FIG. 10 is a view for explaining in more detail another example of the bonding state between the zipper tape and a film. FIG. 11 is a view for explaining in more detail another example of the bonding state between the zipper tape and a film.

[0010] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0011] Fig. 1 is a plan view of a container with zipper tape according to one embodiment of the present invention, and Fig. 2 is a cross-sectional view taken along line II-II in Fig. 1. As shown in the figures, the container with zipper tape 100 includes a bag-shaped container body formed by a film 110 having a first surface 111A facing the storage space SP, and a zipper tape 120 joined to the first surface 111A.

[0012] In the illustrated example, the film 110 has a first surface 111A and a second surface 111B opposite the first surface 111A, and the first surface 111A and the second surface 111B each face the storage space SP. The film 110 is formed, for example, of a single-layer or multi-layer thermoplastic resin. More specifically, the film 110 is formed, for example, of polypropylene, high-density polyethylene (HDPE), or linear low-density polyethylene (LLDPE). The polypropylene is, for example, homopolypropylene (HPP), random polypropylene (RPP), or block polypropylene (BPP). When the film 110 is multi-layered, the surface substrate may be biaxially oriented polypropylene (OPP), biaxially oriented polyethylene terephthalate (OPET), or biaxially oriented nylon (ONy). These are not limited to fossil fuel-derived resins; they may also be environmentally friendly bioplastics (polyolefin-based resins such as biomass-derived biopolypropylene and biopolyethylene), or a mixture of fossil fuel-derived resins and bioplastics. The film 110 may include an inorganic material layer formed by aluminum vapor deposition or lamination of aluminum foil.

[0013] In the illustrated example, two films 110 are joined together at the top seal portion 112, the bottom seal portion 113, and the side seal portion 114 to form the bag-shaped container body, but in other examples, a single film 110 may be folded back at the portion corresponding to the side seal portion 114 to form the bag-shaped container body. Also, a portion where the film 110 is folded inward, a so-called gusset, may be formed at the portion corresponding to the bottom seal portion 113 or the side seal portion 114. In this case, the gusset may be formed by the film 110, or by another film joined to the film 110. Furthermore, the zipper tape-equipped container 100 may be a standing pouch that can be placed upright by forming a gusset at the bottom.

[0014] The zipper tape 120 is bonded to the first surface 111A of the film 110. Specifically, the portion of the second base 121B extending beyond the tear strip 123 (the portion where the thickened portion 125B is formed in the illustrated example), the tear strip 123 (the surface of the strip body 123A opposite the easy-peel layer 123C in the illustrated example), the surface of the first base 121A opposite the first engagement portion 122A, and the easy-peel layer 124 formed on the portion of the second base 121B extending beyond the first base 121A on the opposite side from the tear strip 123 are bonded to the first surface 111A.

[0015] As shown in the cross-sectional view of FIG. 2 , the zipper tape 120 includes base portions 121A and 121B, engaging portions 122A and 122B, a tear strip 123, and an easy-peel layer 124. The base portions 121A and 121B are formed of a first resin composition primarily composed of a polyolefin resin, specifically, for example, polypropylene. For example, the first resin composition may contain low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE). At least a portion of the LDPE or LLDPE may be biopolyethylene. The polyolefin resin, which is the primary component of the first resin composition, is not limited to fossil fuel-derived resins. It may also be environmentally friendly bioplastics (e.g., biomass-derived biopolypropylene or bioethylene polyolefin resins) or a mixture of fossil fuel-derived resins and bioplastics. Known additives, such as stabilizers, antioxidants, lubricants, antistatic agents, or colorants, may be added to the first resin composition as needed.

[0016] The engaging portions 122A and 122B protrude from the base portions 121A and 121B, respectively, and are engageable with each other. In the illustrated example, the first engaging portion 122A has a male profile and the second engaging portion 122B has a female profile, but the opposite may also be true. Furthermore, the zipper is not limited to a male-female configuration; various known zipper engaging portion shapes, such as a combination of claw, hook, or knob shapes, can be used. While the illustrated example shows one pair of engaging portions, multiple pairs of engaging portions may also be provided. The engaging portions 122A and 122B are formed, for example, from the same first resin composition as the base portions 121A and 121B, but a resin composition different from the first resin composition may also be used.

[0017] The tear strip 123 is disposed on a first widthwise side (upper side in FIG. 2 ) of the first base 121A. Because the tear strip 123 is pulled away from the first base 121A when the container is opened, as described below, the tear strip 123 and the first base 121A may be connected by a thin-walled portion as shown, or may be separate. More specifically, the tear strip 123 may be molded as the same member as the first base 121A via a thin-walled portion, as in the example shown in FIG. 2 . In the example shown in FIG. 2 , the thin-walled portion connecting the tear strip 123 to the first base 121A is bonded to the first surface 111A, but there may be a gap between the thin-walled portion and the first surface 111A. In another example, the tear strip 123 may be laminated near the end of the first widthwise side of the first base 121A. In this case, when the tear strip 123 is pulled, it tears not only the first surface 111A but also a portion of the first base 121A to form an opening in the container body. Alternatively, the tear strip 123 may be positioned parallel to the first base 121A as a separate member separate from the first base 121A. In this case, the tear strip 123 may be laminated to the second base 121B, as in the example described below.

[0018] In the illustrated example, the tear strip 123 includes a strip body 123A and an easy-peel layer 123C laminated on the surface of the strip body 123A facing the second base 121B. A bonding layer 123B may be included between the strip body 123A and the easy-peel layer 123C. In this case, the strip body 123A is formed, for example, from a first resin composition, similar to the first base 121A. The easy-peel layer 123C is formed from a resin composition that is releasable from the first resin composition forming the second base 121B, and the bonding layer 123B is formed from a resin composition that can bond the strip body 123A and the easy-peel layer 123C. For example, if the first resin composition is primarily polypropylene as described above, the easy-peel layer 123C is formed from a resin composition primarily polyethylene. In this case, for example, the entire tear strip 123 may be formed from a resin composition containing polyethylene as a main component, and the easy-peel layer 123C may be omitted.

[0019] Although the above description has been given of an example in which the first resin composition forming the bases 121A and 121B is primarily composed of polypropylene, in other examples, the primary component of the first resin composition may be another polyolefin-based resin, such as polyethylene. In this case, if the tear strip 123 includes the main strip body 123A and the easy-peel layer 123C, the easy-peel layer 123C may be formed from a resin composition primarily composed of polypropylene. Furthermore, the primary component of the first resin composition may be a resin other than a polyolefin-based resin.

[0020] As shown, when the bases 121A and 121B are in a predetermined position, the second base 121B includes a portion extending beyond the tear strip 123 on a first widthwise side of the first base 121A and also includes a portion extending beyond the first base 121A on a second widthwise side (the lower side in FIG. 2 ) opposite the first widthwise side. Here, the predetermined position of the bases 121A and 121B is defined as, for example, a state in which the engaging portions 122A and 122B are engaged with each other. However, the engaging portions 122A and 122B do not necessarily have to be engaged; it is sufficient that the engaging portions 122A and 122B are aligned across the width of the bases 121A and 121B. In the illustrated example, a thickened portion 125B is formed at the portion of the second base 121B extending beyond the tear strip 123 on the first widthwise side. A thickened portion 125A is also formed on the first side of the first base portion 121A, i.e., the end portion on the tear strip 123 side. These thickened portions 125A, 125B guide the pulling of the tear strip 123 when opening the package and more reliably form the intended opening shape, but they can also be omitted.

[0021] An easy-peel layer 124 is formed on the portion of the second base 121B extending beyond the first base 121A on the second side. The easy-peel layer 124 is formed of a second resin composition different from the first resin composition forming the bases 121A and 121B. Specifically, the second resin composition is a resin composition that has peelability with respect to the film (first surface 111A) of the container body. Note that, in this specification, "having peelability" means that the peel strength from the target is 30 N / 15 mm or less. In this case, the peel strength is preferably 20 N / 15 mm or less, more preferably 15 N / 15 mm or less, and even more preferably 10 N / 15 mm or less. The lower limit of the peel strength is not particularly limited, but is, for example, 1 N / 15 mm or more. More specifically, the peel strength is measured using a thermal gradient tester. The peel strength between the easy peel layer 124 and the film is 30 N / 15 mm or less when sealed at 230° C. and 0.2 MPa for 1 second.

[0022] In the illustrated example, a thickened portion 126 is formed on the second side of the first base portion 121A, i.e., the end closest to the easy-peel layer 124. By forming the thickened portion 126, the thickness of the zipper tape 120, including the engaging portions 122A and 122B and the tear strip 123, can be made uniform across the entire width of the zipper tape 120. This allows each portion of the zipper tape 120 to be more reliably bonded to the film of a container body, for example, by sandwiching the zipper tape 120 between seal bars in the thickness direction. The thickened portion 126 is formed to be thicker than the other portions of the first base portion 121A, for example. The thickness difference is preferably 100 μm or more, more preferably 200 μm or more, and even more preferably 300 μm or more. There is no particular upper limit to the thickness difference ratio, but considering the typical size of the engaging portions 122A and 122B, it is 600 μm or less.

[0023] The zipper tape 120 as described above is manufactured by, for example, extrusion molding. In this case, a first resin composition forming the bases 121A and 121B and a second resin composition forming the easy-peel layer 124 are co-extruded. In this case, a bonding layer may be laminated between the second base 121B and the easy-peel layer 124. The bonding layer is formed of a resin composition capable of bonding the second base 121B and the easy-peel layer 124. Alternatively, the zipper tape 120 may be manufactured by forming a portion including the bases 121A and 121B by extrusion molding the first resin composition, and then applying the second resin composition to form the easy-peel layer 124. In this case, an intermediate layer may be formed by applying another resin composition between the second base 121B and the easy-peel layer 124.

[0024] As described above, the easy-peel layer 124 is formed of a resin composition (second resin composition) that is peelable from the film 110 including the first surface 111A. Each portion of the zipper tape 120 is joined to the first surface 111A by, for example, heat sealing or ultrasonic sealing. In this case, the easy-peel layer 124 and the first surface 111A may be heat-sealed at a lower temperature than the other portions of the zipper tape 120. In the illustrated example, the easy-peel layer 124 is joined only to the first surface 111A, but it may also be partially joined to the first base portion 121A (thick portion 126 in the illustrated example).

[0025] The second resin composition forming the easy-peel layer 124 may contain, for example, low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE). The first resin composition forming the bases 121A and 121B may also contain LDPE or LLDPE, but in this case, the LDPE or LLDPE content differs between the first and second resin compositions. As described above, the easy-peel layer 124 has peelability from the film 110. Specifically, the peel strength between the easy-peel layer 124 and the film 110 is 30 N / 15 mm or less. In this case, the peel strength is preferably 20 N / 15 mm or less, more preferably 15 N / 15 mm or less, and even more preferably 10 N / 15 mm or less. The lower limit of the peel strength is not particularly limited, but is, for example, 1 N / 15 mm or more. To adjust the peel strength between the easy-peel layer 124 and the film 110, polypropylene may be mixed with the LDPE or LLDPE in the second resin composition. In this case, the polypropylene may be a mixture of homopolypropylene (HPP), random polypropylene (RPP), block polypropylene (BPP), propylene-ethylene-butene-1 random terpolymer, or a special soft polyolefin resin (TPO resin). The second resin composition is not limited to the above examples, and may contain other components that have peelability to the film 110. The easy-peel layer 123C and the easy-peel layer 124 of the tear strip 123 may be formed of the same resin composition or different resin compositions.

[0026] FIG. 3 shows the state of the zipper tape-equipped container shown in FIGS. 1 and 2 when contents are sealed. In the illustrated example, the top seal 112 has not yet been formed when the contents are sealed, so the contents can be stored in the storage space SP without passing through the zipper tape 120. By forming the top seal 112 after the contents are sealed, the storage space SP containing the contents can be sealed with the easy-peel layer 124 of the base 121B bonded to the first surface 111A of the film 110, as shown in FIG. 2. In this state, the engaging portions 122A and 122B of the zipper tape 120 are isolated from the storage space SP by the bond between the easy-peel layer 124 and the first surface 111A. In another example, the contents may be stored in the storage space SP without the bottom seal 113 being formed, and then the bottom seal 113 may be formed after the contents are sealed.

[0027] 4 shows the state of the zipper tape-equipped container of the example shown in FIGS. 1 and 2 when opened. When opening the zipper tape-equipped container 100, the first surface 111A of the film 110 is torn by pulling the tear strip 123 starting from the tab formed by the incision 131, as described above, to form an opening 101 in the zipper tape-equipped container 100. The bases 121A and 121B are separated from each other from the opening 101 side to disengage the engaging portions 122A and 122B, and the easy-peel layer 124 formed on the base 121B is peeled off from the first surface 111A, thereby enabling access to the storage space SP from the outside. As described above, while the easy-peel layer 124 and the first surface 111A are bonded together before opening, the engaging portions 122A and 122B are isolated from the storage space SP, so that the contents do not adhere to the engaging portions 122A and 122B when the container is opened. As a specific application, for example, opening 101 is formed in zipper tape-attached container 100 in which cooking liquid has already been sealed in the state shown in Figure 3, and additional ingredients are sealed into storage space SP through opening 101 in the state shown in Figure 4, and then engaging portions 122A and 122B are engaged again to heat the ingredients together with the cooking liquid.

[0028] 5A and 5B are diagrams for explaining in more detail the bonded state between the zipper tape and the film in the zipper tape container shown in Fig. 1. Fig. 5A and 5B illustrate the length direction (x direction), width direction (y direction), and thickness direction (z direction) of the zipper tape 120 (including the first base portion 121A and the second base portion 121B).

[0029] FIG. 5A corresponds to the state shown in FIG. 3 . The first base portion 121A is joined to the first surface 111A of the film 110 at first bonding portions 141 formed on the surface opposite the first engaging portion 122A. The first bonding portions 141 are alternately arranged with non-bonded portions 142 along the length of the first base portion 121A. The non-bonded portions 142 extend across the first base portion 121A in the width direction. The effect of such non-bonded portions 142 will be described later with reference to FIG. 5B . Meanwhile, the second base portion 121B is joined to the first surface 111A at a portion extending beyond the first base portion 121A on the first side in the width direction, specifically, at a second bonding portion 143 formed on the thick portion 125B, and at a third bonding portion 144 formed on the easy-peel layer 124. Since the second joint 143 and the third joint 144 are formed continuously in the longitudinal direction of the first base 121A, as described above, the contents are prevented from adhering to the engagement portions 122A and 122B.

[0030] Note that when it is stated that "first bonded portions 141 and non-bonded portions 142 are alternately arranged in the length direction (x direction) of first base 121A," this does not necessarily mean that first bonded portions 141 and non-bonded portions 142 are parallel to the width direction (y direction) of first base 121A as shown in the figure, but also includes first bonded portions 141 and non-bonded portions 142 being oblique to the width direction. First bonded portions 141 and non-bonded portions 142 do not have to be alternately arranged over the entire length direction (x direction) of first base 121A, and may be alternately arranged only in a portion, such as near the center of the length direction (x direction). Furthermore, the first bonded portions 141 and non-bonded portions 142 do not have to be alternately arranged only in the length direction (x direction) of the first base 121A, and for example, the first bonded portions 141 and non-bonded portions 142 may also be alternately arranged in the width direction (y direction), and the first bonded portions 141 and non-bonded portions 142 may be arranged in a grid pattern in a plane including the length direction and the width direction (x-y plane). In terms of ease of processing to form the non-bonded portions, a configuration in which the first bonded portions 141 and non-bonded portions 142 are parallel to the width direction (y direction) of the first base 121A and alternately arranged in the length direction (x direction), as in the illustrated example, is preferred.

[0031] 5B shows the state shown in FIG. 4 , i.e., the state in which opening 101 is formed in the container body, easy-peel layer 124 is peeled from first surface 111A, and engaging portions 122A and 122B are re-engaged. When contents (e.g., cooking liquid and ingredients) are heated in a microwave oven or the like in this state, steam is generated, increasing the internal pressure of storage space SP. This causes air containing the generated steam (hereinafter simply referred to as steam) to pass through non-bonded portion 142, which is formed between first base 121A and first surface 111A and spans the width of first base 121A, and is discharged through opening 101. First bonding portion 141 maintains the bond between first base 121A and first surface 111A even during steam discharge, thereby stabilizing the release of steam. More specifically, this prevents the container from losing its shape due to excessive widening of the steam outlet, or prevents excessive steam escape, reducing cooking efficiency.

[0032] The non-bonded portion 142 in the above examples may be a weakly bonded portion formed in the same manner as the easy-peel layer 124. In this case, when the internal pressure of the storage space SP increases, the bond at the weakly bonded portion is broken, forming a non-bonded portion that traverses the first base 121A in the width direction, from which steam is discharged. In these examples, the non-bonded portion 142 and the weakly bonded portion traverse the first base 121A in the width direction, but the first bonded portion 141 does not necessarily have to traverse the first base 121A in the width direction. For example, a communication path may be formed between parallel non-bonded portions 142 and weakly bonded portions in the middle of the width direction of the first base 121A, thereby dividing the first bonded portion 141.

[0033] In the example shown in Figure 5A, the tear strip 123 is joined to the first surface 111A by a fourth joint 145 that extends continuously along the length of the first base 121A. In this case, the non-jointed portion 142 is not formed across at least a portion of the width of the tear strip 123. Because the tear strip 123 is removed when the opening 101 is formed as shown in Figure 5B, the shape of the joint of the tear strip 123 is not particularly limited. To further reduce the possibility of resin flow blocking the non-jointed portion 142 on the first base 121A side during joint formation, the first joint 141 and the non-jointed portion 142 may extend across part or all of the width of the tear strip 123.

[0034] FIG. 6 is a cross-sectional view showing an example of a zipper tape according to an embodiment of the present invention. As described above, the present invention can also be implemented using the zipper tape 120 before it is attached to the film of a container body to form a zipper tape-equipped container. The configuration of each part of the zipper tape 120 shown in FIG. 6 is similar to that described with reference to FIG. 2 , and therefore a detailed description thereof will be omitted. The zipper tape 120 may also have non-bonded or weakly bonded parts that are alternately arranged with bonded parts along the length of the first base 121A and cross the width of the first base 121A. The non-bonded or weakly bonded parts before the zipper tape 120 is bonded to the film have the same shape as the non-bonded parts 142 or weakly bonded parts shown in FIG. 5A , for example, and appear on the zipper tape 120 as regions that incorporate or are coated with a resin material that has low bonding strength with the film or a resin material that has a high melting point and therefore does not melt at the normal sealing temperature between the film and other parts of the first base 121A. The portions other than the non-bonded portion or weakly bonded portion become bonded portions that can be bonded to a film by ordinary heat sealing, etc. It is also possible to form the non-bonded portion 142 or the weakly bonded portion by, for example, forming a slit in the shape of the seal bar that bonds the zipper tape 120 to the film. In this case, the non-bonded portion and the weakly bonded portion do not need to be formed in the first base portion 121A before the zipper tape 120 is bonded to the film.

[0035] FIG. 7 is a cross-sectional view showing a modified zipper tape according to an embodiment of the present invention. The zipper tape 120 shown in FIG. 7 differs from the above-described example in that the tear strip 123 is separated from the first base portion 121A and laminated to the second base portion 121B. The remaining configuration is the same as the above-described example. In this case, the tear strip 123 includes an easy-peel layer 123C, a bonding layer 123B, and a strip body 123A laminated in this order from the second base portion 121B side. When the first base portion 121A and the second base portion 121B are bonded to the first surface 111A of the container body, the tear strip 123 is also bonded to the first surface 111A at the strip body 123A.

[0036] Fig. 8 is a cross-sectional view showing another modified example of the zipper tape according to the embodiment of the present invention. The zipper tape 120 shown in Fig. 8 differs from the above-described examples in that the thick portion 126 is not formed in the first base portion 121A. The rest of the configuration is the same as the example shown in Fig. 6 or the example shown in Fig. 7.

[0037] 9A and 9B are diagrams for explaining in more detail another example of the bonded state between the zipper tape and the film. In these diagrams, the length direction (x direction), width direction (y direction), and thickness direction (z direction) of the zipper tape 120 (including the first base portion 121A and the second base portion 121B) are illustrated. The second bonded portion 143 and the third bonded portion 144 between the second base portion 121B and the first surface 111A are the same as those in the example shown in FIGS. 5A and 5B .

[0038] 9A , first base 121A is joined to first surface 111A of film 110 by first joining portion 141 formed on the surface opposite first engaging portion 122A. In a portion of first base 121A in the width direction, specifically the portion on the storage space SP side, first non-joint portions 142A are formed continuously in the length direction of first base 121A, while in the remaining portion, first joining portions 141 are alternately arranged with second non-joint portions 142B. Second non-joint portions 142B, together with first non-joint portions 142A, traverse first base 121A in the width direction. As shown in Figure 9B, in this example as well, after opening 101 is formed and the bond between easy-peel layer 124 and first surface 111A is destroyed, when the internal pressure of storage space SP increases due to heating of the contents, steam can be discharged from opening 101 through non-bonded portions 142A, 142B, and the bond is maintained at first bonded portion 141, thereby stabilizing the discharge of steam.

[0039] 9A and 9B, the non-bonded portions 142A and 142B may also be weakly bonded portions formed in the same manner as the easy-peel layer 124. Although the zipper tape 120 shown in FIG. 8 is illustrated in FIGS. 9A and 9B, a similar configuration is also possible with the zipper tape shown in FIGS. 6 and 7.

[0040] 100...container with zipper tape, 101...opening, 110...film, 111A...first surface, 111B...second surface, 112...top seal portion, 113...bottom seal portion, 114...side seal portion, 120...zipper tape, 121A...first base portion, 121B...second base portion, 122A...first engaging portion, 122B...second engaging portion, 123... Tear strip, 123A...strip body, 123B...bonding layer, 123C...easy peel layer, 124...easy peel layer, 125A, 125B, 126...thickened portion, 141...first bonding portion, 142...non-bonding portion, 142A...first non-bonding portion, 142B...second non-bonding portion, 143...second bonding portion, 144...third bonding portion, 145...fourth bonding portion.

Claims

1. A container with zipper tape, in which zipper tape is attached to a film forming a container body, the zipper tape comprising: a first base; a tear strip disposed on a first side in the width direction of the first base; a second base including a portion extending beyond the tear strip on the first side and extending beyond the first base on a second side opposite the first side; first and second engaging portions projecting from the first and second bases, respectively, and engageable with each other; and an easy-peel layer formed on the surface of the second base extending beyond the first base on the second side, the first base being joined to the film at a first bonding portion formed on the surface opposite the first engaging portion; the first bonding portion being arranged alternately with non-bonded or weakly bonded portions extending across the first base in the width direction along the length of the first base; the second base is joined to the film at a second seam formed on the first side at a portion extending beyond the tear strip and a third seam formed on the easy-peel layer, and the second seam and the third seam are formed continuously in the length direction.

2. The container with zipper tape according to claim 1, wherein the non-bonded or weakly bonded portions include first non-bonded or weakly bonded portions that are formed continuously in the length direction over a portion of the width direction of the first base, and second non-bonded or weakly bonded portions that are arranged alternately with the first bonded portions in the length direction over the remaining portion of the width direction of the first base.

3. The zipper tape container of claim 1 or claim 2, wherein the tear strip is formed continuously with the first base and is joined to the film at a fourth joint formed continuously in the length direction.

4. A zipper tape comprising: a first base; a tear strip disposed on a first side in the width direction of the first base; a second base including a portion extending beyond the tear strip on the first side and extending beyond the first base on a second side opposite the first side; first and second engaging portions projecting from the first and second bases, respectively, and engageable with each other; and an easy-peel layer formed on a surface of the second base facing the first base and extending beyond the first base on the second side, wherein non-bonded or weakly bonded portions are formed on the surface of the first base opposite the first engaging portion, the non-bonded or weakly bonded portions being arranged alternately with bonded portions in the length direction of the first base and extending across the first base in the width direction.

5. The zipper tape of claim 4, wherein the non-bonded or weakly bonded portions include first non-bonded or weakly bonded portions that are formed continuously in the length direction over a portion of the width direction of the first base, and second non-bonded or weakly bonded portions that are arranged alternately with the bonded portions in the length direction over the remaining portion of the width direction of the first base.

6. The zipper tape according to claim 4 or 5, wherein the tear strip is formed continuously with the first base portion, and the non-bonded portion or the weakly bonded portion is not formed in at least a portion of the tear strip in the width direction.

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